WorldWideScience

Sample records for closed soil-less system

  1. Cultivar of Gerbera grown in soil less culture on inert substrates with open and closed systems in comparison with a traditional cultivation on soil in beds; Coltivazione di gerbera in idroponica su substrato con sistema di irrigazione a ciclo aperto e a ciclo chiuso a confronto con la coltivazione tradizionale in cassone su terriccio

    Energy Technology Data Exchange (ETDEWEB)

    Schiavi, A [MIRAAF, Istituto Sperimentale per l` Orticultura (Italy). Sezione di Ascoli Piceno; Venezia, A [Istituto Sperimentale per l` Orticoltura (Italy). Sezione di Montanaso Lomabardo; Martignon, G [Centro Ricerca Ambiente e Materiali, Unita` Calore residuo e Biomasse, Gruppo Agritermia, Milan (Italy)

    1996-01-01

    The aim of the experiment was the evaluation of the yield of several cultivar of gerbera grown in soil less culture on inert substrates with open and closed systems, in comparison with a traditional cultivation on soil in beds. The trial was carried out in the experimental station at Tavazzano (Milan), in a iron plastic greenhouse heated with the waste water discharged by the local thermo electrical power plant. Two inert substrates (rokwool and perlite) were tested in soil less culture both with an open system and a closed system, based on the reuse of the drained nutrient solution. The cultivars Rosula, Pascal, Queen Rebecca, Horizon, Sunspot e Fleur were utilized, grown with a plant density of 10 plants/mq. The trial started in april 1993 and ended in december 1994. The results have pointed out statistically significative differences in the production of cut flower in the growing systems tested. Plants grown in soil less culture with open system gave a number of cut flowers/plant higher both than those grown on soil and with soil less closed system. Agriperlite gave a better commercially yield than rockwool in soil less culture. The distribution of commercial cut flowers in the three category considered (extra, first and second class) was the same for the all thesis; the not marketable production was lower for plant grown on soil than on both the soil less culture systems. With regard to the response of the cultivar, Queen Rebecca and Pascal gave a commercial yield of about 30 cut flowers/plant higher than Rosula, Horizon and Fleur; the cultivar SunSpot showed the lower yield (17 cut flowers/plant).

  2. Soil less culture; I sistemi di coltivazione senza suolo

    Energy Technology Data Exchange (ETDEWEB)

    Martignon, G [ENEL DSR, Centro Ricerche Ambiente e Materiali, Milan (Italy); Venezia, A [MIRAAF, Istituto Sperimentale per l` Orticultura (Italy) Sezione di Montanaso Lombardo

    1996-01-01

    The paper gives a general view of techniques and systems related to soil less culture developed in the last years (on substrate in beg; NFT; Ebb-Flood, aeroponic,..) taking into account their management and problems (water quality, control of plant nutrition and irrigation; substrates; pathological aspects,..). The evolution, now in progress, of soil less culture from open to closed system as a way to realized an environmental friendly growing system, is considered. When plants are grown with open cycle techniques a large amount of waste solution, with an a high content of nutrients, are discharged in soil and water. Furthermore, they need an extra-utilization of water and fertilizers. Another aspect is the utilization of low cost substrates, which can be reused for more than one cultural cycle without negative effects on yield, and also finally discharged without negative effects on the environment. The development of soil less culture in countries, such as Italy, where only in the last few years the growers show an increasing attention to these new growing systems, is strongly depending on a improvement of research activities, to obtain growing techniques at low cost, easy to manage, able to give good yield and quality. At the same time very useful is a extensive diffusion of scientific results, joined together with the availability of a technical support for the growers.

  3. Short evaluations on hydroponic systems with closed cycle; Prime valutazioni su sistemi idroponici a ciclo chiuso

    Energy Technology Data Exchange (ETDEWEB)

    Martignon, G [ENEL DSR, Centro Ricerche Ambiente e Materiali, Milan (Italy); Venezia, A [MIRAAF, Istituto Sperimentale per l` Orticultura (Italy) Sezione di Montanaso Lombardo

    1996-01-01

    In the experimental station at Tavazzano from 1993 to 1995 several trials were carried out growing vegetables, cut flowers and ornamental species with soil less culture. Different soil less techniques were utilized (on substrate in begs with open system; NFT, Ebb-Flood, sub irrigation on substrate in pot with closed system). The results obtained till now give the possibility to make some comments about management and problems of the soil less systems. The paper shows aspects related to the management of plant nutrition (nutrient solution, irrigation, substrates)and to fruit or flower production. The environmental effects of the different closed soil less culture systems tested are described, with respect to the cultivation on substrate in beg with open system, still generally utilized.

  4. Closing the water and nutrient cycles in soilless cultivation systems

    NARCIS (Netherlands)

    Beerling, E.A.M.; Blok, C.; Maas, van der A.A.; Os, van E.A.

    2014-01-01

    Soilless cultivation systems are common in Dutch greenhouse horticulture, i.e., less than 20% of the greenhouse area is still soil grown. For long, it was assumed that in these so-called closed systems the emission of nutrients and plant protection products (PPPs) was close to zero. However, Water

  5. Biochar application reduce ammonia volatilization in a soil-plant system: A closed chamber experiment

    Science.gov (United States)

    Mandal, Sanchita; Donner, Erica; Smith, Euan; Lombi, Enzo

    2017-04-01

    Ammonia (NH3) volatilization is considered as one of the major mechanisms responsible for the loss of nitrogen (N) from soil-plant systems worldwide. About 10-30% of N can be lost as NH3 volatilization, which constitutes a significant economic loss. In recent years carbon-based materials such as biochar have created a great research interest because of their ability to increase soil fertility by reducing nutrient loss and pollutants bioavailability in soil. Most of the studies so far have investigated how biochar addition can reduce NH3 volatilization from soils but less information is available for soil-plant systems. In this research, wheat plants (Triticum aestivum, variety: Calingiri) were grown in a calcareous soil (pH 8, calcarosol) inside a closed chamber system to assess both ammonia volatilization and plant N uptake. In this specialized glass chamber air was passed through an inlet where the flow rate was maintained using an air pump (3.5 L min-1). The air outlet was passed through a sulphuric acid trap which was used to capture the volatilized NH3 from the chamber. Plants were watered using the inlet to maintain 50% field capacity throughout the incubation. Two different biochar samples were used in this study: a poultry manure biochar (PM-BC) and a green waste compost biochar (GW-BC) produced at 250 ˚C. Five different application rates were tested (0, 0.5, 1, 1.5, and 2%). The soil was mixed with biochar samples, water, N, P, K, Ca, Mg, and S for one week before sowing. After one week of germination, plants were transferred to the chamber for further three weeks incubation for NH3 volatilization measurement. The study identified that biochar application reduced the NH3 volatilization and increase the plant biomass. Biochar application at 0.5 and 2% decreased the NH3 volatilization by 36 and 48% respectively. The N uptake of the plants also increased from 2.9 to 28% at 0.5 and 2% application rates respectively. The dry biomass of the plant also increased

  6. Mass balance of pent achloroni trobenzene-14c and metabolites in a closed aerated soil plant or soil-system

    International Nuclear Information System (INIS)

    Kamal, M.

    1984-01-01

    Two experiments were carried out with pentachloronitrobenzene- 14 C and soils with and without plants in a closed aerated laboratory system. In both experiments, degradation to 14 CO 2 within 16 or 53 days, respectively, was very low (=0,01% of initially applied 14 C). Volatilization loses were about 15% in the system with plants (16 days) and were negligible in the soil without plants (53 days). The uptake into plants within 16 days was 5.26% of initially applied 14 C(0.86% unchanged parent compound, 3.35% soluble metabolites, and 1.05% unextractable residues); the major portion of soluble metabolites was highly polar conjugates which were not characterized further. The radioactivity left in both soils after 16 or 53 days, respectively, considered of 57 or 37% unchanged parent compound, 10 or 42% soluble metabolites, and 13 or 25% soil-bound residues. In the soil without plants, the following conversion products were identified after 53 days: pentachloroaniline (18.7% of initially applied 14 C), pentachlorthioanisole (17.3%), pentachlorobenzene, and pentachlorophenylmethylsulphoxide (2.6% each). (author)

  7. Long-term monitoring of soil gas fluxes with closed chambers using automated and manual systems

    Energy Technology Data Exchange (ETDEWEB)

    Scott, A.; Crichton, I.; Ball, B.C.

    1999-10-01

    The authors describe two gas sample collection techniques, each of which is used in conjunction with custom made automated or manually operated closed chambers. The automated system allows automatic collection of gas samples for simultaneous analysis of multiple trace gas efflux from soils, permitting long-term monitoring. Since the manual system is cheaper to produce, it can be replicated more than the automated and used to estimate spatial variability of soil fluxes. The automated chamber covers a soil area of 0.5 m{sup 2} and has a motor driven lid that remains operational throughout a range of weather conditions. Both systems use gas-tight containers of robust metal construction, which give good sample retention, thereby allowing long-term storage and convenience of transport from remote locations. The containers in the automated system are filled by pumping gas from the closed chamber via a multiway rotary valve. Stored samples from both systems are analyzed simultaneously for N{sub 2}O and CO{sub 2} using automated injection into laboratory-based gas chromatographs. The use of both collection systems is illustrated by results from a field experiment on sewage sludge disposal to land where N{sub 2}O fluxes were high. The automated gas sampling system permitted quantification of the marked temporal variability of concurrent N{sub 2}O and CO{sub 2} fluxes and allowed improved estimation of cumulative fluxes. The automated measurement approach yielded higher estimates of cumulative flux because integration of manual point-in-time observations missed a number of transient high-flux events.

  8. A Computational Model of Water Migration Flux in Freezing Soil in a Closed System

    Institute of Scientific and Technical Information of China (English)

    裘春晗

    2005-01-01

    A computational model of water migration flux of fine porous soil in frost heave was investigated in a closed system. The model was established with the heat-mass conservation law and from some previous experimental results. Through defining an auxiliary function an empirical function in the water migration flux, which is difficult to get, was replaced. The data needed are about the water content along the soft colunm after test with enough long time. We adopt the test data of sample soil colunms in [1] to verify the model. The result shows it can reflect the real situation on the whole.

  9. Ecological Challenges for Closed Systems

    Science.gov (United States)

    Nelson, Mark; Dempster, William; Allen, John P.

    2012-07-01

    Closed ecological systems are desirable for a number of purposes. In space life support systems, material closure allows precious life-supporting resources to be kept inside and recycled. Closure in small biospheric systems facilitates detailed measurement of global ecological processes and biogeochemical cycles. Closed testbeds facilitate research topics which require isolation from the outside (e.g. genetically modified organisms; radioisotopes) so their ecological interactions and fluxes can be studied separate from interactions with the outside environment. But to achieve and maintain closure entails solving complex ecological challenges. These challenges include being able to handle faster cycling rates and accentuated daily and seasonal fluxes of critical life elements such as carbon dioxide, oxygen, water, macro- and mico-nutrients. The problems of achieving sustainability in closed systems for life support include how to handle atmospheric dynamics including trace gases, producing a complete human diet and recycling nutrients and maintaining soil fertility, the sustaining of healthy air and water and preventing the loss of crucial elements from active circulation. In biospheric facilities the challenge is also to produce analogues to natural biomes and ecosystems, studying processes of self-organization and adaptation in systems that allow specification or determination of state variables and cycles which may be followed through all interactions from atmosphere to soils. Other challenges include the dynamics and genetics of small populations, the psychological challenges for small isolated human groups and measures and options which may be necessary to ensure long-term operation of closed ecological systems.

  10. Closed depression topography and Harps soil, revisited

    Science.gov (United States)

    The Harps soil (Fine-loamy, mixed superactive, mesic Typic Calciaquoll) developed around wetland depressions. The purpose of this study is 1) to delineate surface deposition of carbonates representing Harps soil which results from outward and upward flow around closed depressions, and 2) to relate t...

  11. Neutron probe measurement of soil water content close to soil surface

    International Nuclear Information System (INIS)

    Faleiros, M.C.; Ravelo S, A.; Souza, M.D. de

    1993-01-01

    The problem of neutron probe soil water content measurements close to soil surface is analysed from the spatial variability and also from the slow neutron loss to the atmosphere points of view. Results obtained on a dark red latosol of the county of Piracicaba, SP, indicate the possibility of precisely measuring the neutron sphere of influence when different media are used on soil surface. (author). 7 refs, 5 figs, 1 tab

  12. Assessing soil ecotoxicity of methyl tert-butyl ether using earthworm bioassay; closed soil microcosm test for volatile organic compounds

    International Nuclear Information System (INIS)

    An, Youn-Joo

    2005-01-01

    An earthworm bioassay was conducted to assess ecotoxicity in methyl tert-butyl ether (MTBE)-amended soils. Ecotoxicity of MTBE to earthworms was evaluated by a paper contact method, natural field soil test, and an OECD artificial soil test. All tests were conducted in closed systems to prevent volatilization of MTBE out of test units. Test earthworm species were Perionyx excavatus and Eisenia andrei. Mortality and abnormal morphology of earthworms exposed to different concentrations of MTBE were examined. MTBE was toxic to both earthworm species and the severity of response increased with increasing MTBE concentrations. Perionyx excavatus was more sensitive to MTBE than Eisenia andrei in filter papers and two different types of soils. MTBE toxicity was more severe in OECD artificial soils than in field soils, possibly due to the burrowing behavior of earthworms into artificial soils. The present study demonstrated that ecotoxicity of volatile organic compounds such as MTBE can be assessed using an earthworm bioassay in closed soil microcosm with short-term exposure duration. - Earthworm bioassay can be a good protocol to assess soil ecotoxicity of volatile organic compounds such as MTBE

  13. Potentials and challenges associated with automated closed dynamic chamber measurements of soil CO2 fluxes

    Science.gov (United States)

    Görres, Carolyn-Monika; Kammann, Claudia; Ceulemans, Reinhart

    2015-04-01

    Soil respiration fluxes are influenced by natural factors such as climate and soil type, but also by anthropogenic activities in managed ecosystems. As a result, soil CO2 fluxes show a large intra- and interannual as well as intra- and intersite variability. Most of the available soil CO2 flux data giving insights into this variability have been measured with manually closed static chambers, but technological advances in the past 15 years have also led to an increased use of automated closed chamber systems. The great advantage of automated chambers in comparison to manually operated chambers is the higher temporal resolution of the flux data. This is especially important if we want to better understand the effects of short-term events, e.g. fertilization or heavy rainfall, on soil CO2 flux variability. However, the chamber method is an invasive measurement method which can potentially alter soil CO2 fluxes and lead to biased measurement results. In the peer-reviewed literature, many papers compare the field performance and results of different closed static chamber designs, or compare manual chambers with automated chamber systems, to identify potential biases in CO2 flux measurements, and thus help to reduce uncertainties in the flux data. However, inter-comparisons of different automated closed dynamic chamber systems are still lacking. Here we are going to present a field comparison of the most-cited automated chamber system, the LI-8100A Automated Soil Flux System, with the also commercially available Greenhouse Gas Monitoring System AGPS. Both measurement systems were installed side by side at a recently harvested poplar bioenergy plantation (POPFULL, http://uahost.uantwerpen.be/popfull/) from April 2014 until August 2014. The plantation provided optimal comparison conditions with a bare field situation after the harvest and a regrowing canopy resulting in a broad variety of microclimates. Furthermore, the plantation was planted in a double-row system with

  14. Key ecological challenges for closed systems facilities

    Science.gov (United States)

    Nelson, Mark; Dempster, William F.; Allen, John P.

    2013-07-01

    Closed ecological systems are desirable for a number of purposes. In space life support systems, material closure allows precious life-supporting resources to be kept inside and recycled. Closure in small biospheric systems facilitates detailed measurement of global ecological processes and biogeochemical cycles. Closed testbeds facilitate research topics which require isolation from the outside (e.g. genetically modified organisms; radioisotopes) so their ecological interactions and fluxes can be studied separate from interactions with the outside environment. But to achieve and maintain closure entails solving complex ecological challenges. These challenges include being able to handle faster cycling rates and accentuated daily and seasonal fluxes of critical life elements such as carbon dioxide, oxygen, water, macro- and mico-nutrients. The problems of achieving sustainability in closed systems for life support include how to handle atmospheric dynamics including trace gases, producing a complete human diet, recycling nutrients and maintaining soil fertility, the maintenance of healthy air and water and preventing the loss of critical elements from active circulation. In biospheric facilities, the challenge is also to produce analogues to natural biomes and ecosystems, studying processes of self-organization and adaptation in systems that allow specification or determination of state variables and cycles which may be followed through all interactions from atmosphere to soils. Other challenges include the dynamics and genetics of small populations, the psychological challenges for small isolated human groups and backup technologies and strategic options which may be necessary to ensure long-term operation of closed ecological systems.

  15. Measurement of N2O and CH4 soil fluxes from garden, agricultural and natural soils using both closed and open chamber systems coupled with high-precision CRDS analyzer

    Science.gov (United States)

    He, Yonggang; Jacobson, Gloria; Alexander, Chris; Fleck, Derek; Hoffnagel, John; Del Campo, Bernardo; Rella, Chris

    2013-04-01

    Studying the emission and uptake of greenhouse gases from soil is essential for understanding, adapting to and ultimately mitigating the effects of climate change. To-date, majority of such studies have been focused on carbon dioxide (CO2 ) , however, in 2006 the EPA estimated that "Agricultural activities currently generate the largest share, 63 percent, of the world's anthropogenic non-carbon dioxide (non-CO2) emissions (84 percent of nitrous oxide [N2O] and 52 percent of methane[CH4]), and make up roughly 15 percent of all anthropogenic greenhouse gas emissions" (Prentice et al., 2001). Therefore, enabling accurate N2O and CH4 flux measurements in the field are clearly critical to our ability to better constrain carbon and nitrogen budgets, characterize soil sensitivities, agricultural practices, and microbial processes like denitrification and nitrification. To aide in these studies, Picarro has developed a new analyzer based on its proven, NIR technology platform, which is capable of measuring both N2O and CH4 down to ppb levels in a single, field-deployable analyzer. This analyzer measures N2O with a 1-sigma, precision of 3.5 ppb and CH4 with a 1-sigma precision of 3ppb on a 5 minute average. The instrument also has extremely low drift to enable accurate measurements with infrequent calibrations. The data rate of the analyzer is on the order of 5 seconds in order to capture fast, episodic emission events. One of the keys to making accurate CRDS measurements is to thoroughly characterize and correct for spectral interfering species. This is especially important for closed system soil chambers used on agricultural soils where a variety of soil amendments may be applied and gases not usually present in ambient air could concentrate to high levels. In this work, we present the results of analyzer interference testing and corrections completed for the interference of carbon dioxide, methane, ammonia, ethane, ethylene, acetylene, and water on N2O. In addition, we

  16. Noble gases from solar energetic particles revealed by closed system stepwise etching of lunar soil minerals

    International Nuclear Information System (INIS)

    Wieler, R.; Baur, H.; Signer, P.

    1986-01-01

    He, Ne, and Ar abundances and isotopic ratios in plagioclase and pyroxene separates from lunar soils were determined using a closed system stepwise etching technique. This method of noble gas release allows one to separate solar wind (SW) noble gases from those implanted as solar energetic particles (SEP). SEP-Ne with 20 Ne/ 22 Ne = 11.3 +- 0.3 is present in all samples studied. The abundances of SEP-Ne are 2-4 orders of magnitude too high to be explained exclusively as implanted solar flare gas. The major part of SEP-Ne possibly originates from solar 'suprathermal ions' with energies < 0.1 MeV/amu. The isotopic composition of Ne in these lower energy SEP is, however, probably identical to that of real flare Ne. The suggestion that SEP-Ne might have the same isotopic composition as planetary Ne and thus possibly represent an unfractionated sample of solar Ne is not tenable. SW-Ne retained in plagioclase and pyroxene is less fractionated than has been deduced by total fusion analyses. Ne-B is a mixture of SW-Ne and SEP-Ne rather than fractionated SW-Ne. In contrast to SEP-Ne, SEP-Ar has probably a very similar composition as SW-Ar. (author)

  17. The Legacy of Biosphere 2 for Biospherics and Closed Ecological System Research

    Science.gov (United States)

    Allen, J.; Alling, A.; Nelson, M.

    The unprecedented challenges of creating Biosphere 2, the world's first laboratory for biospherics, the study of global ecology and long-term closed ecological system dynamics led to breakthrough developments in many fields, and a deeper understanding of the opportunities and difficulties of material closure. This paper will review these accomplishments and challenges, citing some of the key research accomplishments and publications which have resulted from the experiments in Biosphere 2. Engineering accomplishments included development of a technique for variable volume to deal with pressure differences between the facility and outside environment, developing methods of leak detection and sealing, and achieving new standards of closure, with an annual atmospheric leakrate of less than 10%, or less than 300 ppm per day. This degree of closure permitted detailed tracking of carbon dioxide, oxygen, and trace gases such as nitrous oxide and ethylene over the seasonal variability of two years. Full closure also necessitated developing new approaches and technologies for complete air, water, and wastewater recycle and reuse within the facility. The development of a soil-based highly productive agricultural system was a first in closed ecological systems, and much was learned about managing a wide variety of crops using non-chemical means of pest and disease control. Closed ecological systems have different temporal b ogeochemical cycling and ranges ofi atmospheric components because of their smaller reservoirs of air, water and soil, and higher concentration of biomass, and Biosphere 2 provided detailed examination and modeling of these accelerated cycles over a period of closure which measured in years. Medical research inside Biosphere 2 included the effects on humans of lowered oxygen: the discovery that human productivity can be maintained down to 15% oxygen could lead to major economies on the design of space stations and planetary/lunar settlements. The improved

  18. Can Fertilization of Soil Select Less Mutualistic Mycorrhizae?

    Science.gov (United States)

    Johnson, Nancy Collins

    1993-11-01

    It has been noted previously that nutrient-stressed plants generally release more soluble carbohydrate in root exudates and consequently support more mycorrhizae than plants supplied with ample nutrients. Fertilization may select strains of vesicular-arbuscular mycorrhizal (VAM) fungi that are inferior mutualists if the same characteristics that make a VAM fungus successful in roots with a lowered carbohydrate content also reduce the benefits that the fungus provides a host plant. This two-phase study experimentally tests the hypothesis that fertilizing low-nutrient soil selects VAM fungi that are inferior mutualists. The first phase examines the effects of chemical fertilizers on the species composition of VAM fungal communities in long-term field plots. The second phase measures the effects of VAM fungal assemblages from fertilized and unfertilized plots on big bluestem grass grown in a greenhouse. The field results indicate that 8 yr of fertilization altered the species composition of VAM fungal communities. Relative abundance of Gigaspora gigantea, Gigaspora margarita, Scutellispora calospora, and Glomus occultum decreased while Glomus intraradix increased in response to fertilization. Results from the greenhouse experiment show that big bluestem colonized with VAM fungi from fertilized soil were smaller after 1 mo and produced fewer inflorescences at 3 mo than big bluestem colonized with VAM fungi from unfertilized soil. Fungal structures within big bluestem roots suggest that VAM fungi from fertilized soil exerted a higher net carbon cost on their host than VAM fungi from unfertilized soil. VAM fungi from fertilized soil produced fewer hyphae and arbuscules (and consequently provided their host with less inorganic nutrients from the soil) and produced as many vesicles (and thus provisioned their own storage structures at the same level) as fungi from unfertilized soil. These results support the hypothesis that fertilization selects VAM fungi that are inferior

  19. Study on closed cycle MHD generation systems; Closed cycle MHD hatsuden system no kento

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1988-03-01

    The closed cycle noble gas MHD generation systems are surveyed and studied. The concept of closed cycle noble gas MHD generation is confirmed to extract high enthalpy, and now going into the engineering demonstration stage from the basic research stage. These systems have various characteristics. The highest working temperature is around 1,700 degrees C, which is close to that associated with the existing techniques. Use of helium or argon gas as the working fluid makes the system relatively free of various problems, e.g., corrosion. It can attain a much higher efficiency than the combined cycle involving gas turbine. It suffers less heat loss in the passages, is suitable for small- to medium-capacity power generation systems, and copes with varying load. The compact power generation passages decrease required size of the superconducting magnet. The technical problems to be solved include optimization of power generation conditions, demonstration of durability of the power generation passages, injection/recovery of the seed material, treatment of the working gas to remove molecular impurities, and development of heat exchangers serviceable at high temperature produced by direct combustion of coal. The conceptual designs of the triple combined system are completed. (NEDO)

  20. The water cycle in closed ecological systems: Perspectives from the Biosphere 2 and Laboratory Biosphere systems

    Science.gov (United States)

    Nelson, Mark; Dempster, W. F.; Allen, J. P.

    2009-12-01

    To achieve sustainable, healthy closed ecological systems requires solutions to challenges of closing the water cycle - recycling wastewater/irrigation water/soil medium leachate and evaporated water and supplying water of required quality as needed for different needs within the facility. Engineering Biosphere 2, the first multi-biome closed ecological system within a total airtight footprint of 12,700 m 2 with a combined volume of 200,000 m 3 with a total water capacity of some 6 × 10 6 L of water was especially challenging because it included human inhabitants, their agricultural and technical systems, as well as five analogue ecosystems ranging from rainforest to desert, freshwater ecologies to saltwater systems like mangrove and mini-ocean coral reef ecosystems. By contrast, the Laboratory Biosphere - a small (40 m 3 volume) soil-based plant growth facility with a footprint of 15 m 2 - is a very simplified system, but with similar challenges re salinity management and provision of water quality suitable for plant growth. In Biosphere 2, water needs included supplying potable water for people and domestic animals, irrigation water for a wide variety of food crops, and recycling and recovering soil nutrients from wastewater. In the wilderness biomes, providing adequately low salinity freshwater terrestrial ecosystems and maintaining appropriate salinity and pH in aquatic/marine ecosystems were challenges. The largest reservoirs in Biosphere 2 were the ocean/marsh with some 4 × 10 6 L, soil with 1 to 2 × 10 6 l, primary storage tank with 0 to 8 × 10 5 L and storage tanks for condensate and soil leachate collection and mixing tanks with a capacity of 1.6 × 10 5 L to supply irrigation for farm and wilderness ecosystems. Other reservoirs were far smaller - humidity in the atmosphere (2 × 10 3 L), streams in the rainforest and savannah, and seasonal pools in the desert were orders of magnitude smaller (8 × 10 4 L). Key technologies included condensation from

  1. The legacy of Biosphere 2 for the study of biospherics and closed ecological systems.

    Science.gov (United States)

    Allen, J P; Nelson, M; Alling, A

    2003-01-01

    The unprecedented challenges of creating Biosphere 2, the world's first laboratory for biospherics, the study of global ecology and long-term closed ecological system dynamics, led to breakthrough developments in many fields, and a deeper understanding of the opportunities and difficulties of material closure. This paper will review accomplishments and challenges, citing some of the key research findings and publications that have resulted from the experiments in Biosphere 2. Engineering accomplishments included development of a technique for variable volume to deal with pressure differences between the facility and outside environment, developing methods of atmospheric leak detection and sealing, while achieving new standards of closure, with an annual atmospheric leakrate of less than 10%, or less than 300 ppm per day. This degree of closure permitted detailed tracking of carbon dioxide, oxygen, and trace gases such as nitrous oxide and ethylene over the seasonal variability of two years. Full closure also necessitated developing new approaches and technologies for complete air, water, and wastewater recycle and reuse within the facility. The development of a soil-based highly productive agricultural system was a first in closed ecological systems, and much was learned about managing a wide variety of crops using non-chemical means of pest and disease control. Closed ecological systems have different temporal biogeochemical cycling and ranges of atmospheric components because of their smaller reservoirs of air, water and soil, and higher concentration of biomass, and Biosphere 2 provided detailed examination and modeling of these accelerated cycles over a period of closure which measured in years. Medical research inside Biosphere 2 included the effects on humans of lowered oxygen: the discovery that human productivity can be maintained with good health with lowered atmospheric oxygen levels could lead to major economies on the design of space stations and

  2. The legacy of biosphere 2 for the study of biospherics and closed ecological systems

    Science.gov (United States)

    Allen, J. P.; Nelson, M.; Alling, A.

    The unprecedented challenges of creating Biosphere 2, the world's first laboratory for biospherics, the study of global ecology and long-term closed ecological system dynamics, led to breakthrough developments in many fields, and a deeper understanding of the opportunities and difficulties of material closure. This paper will review accomplishments and challenges, citing some of the key research findings and publications that have resulted from the experiments in Biosphere 2. Engineering accomplishments included development of a technique for variable volume to deal with pressure differences between the facility and outside environment, developing methods of atmospheric leak detection and sealing, while achieving new standards of closure, with an annual atmospheric leakrate of less than 10%, or less than 300 ppm per day. This degree of closure permitted detailed tracking of carbon dioxide, oxygen, and trice gases such as nitrous oxide and ethylene over the seasonal variability of two years. Full closure also necessitated developing new approaches and technologies for complete air, water, and wastewater recycle and reuse within the facility. The development of a soil-based highly productive agricultural system was a first in closed ecological systems, and much was learned about managing a wide variety of crops using non-chemical means of pest and disease control. Closed ecological systems have different temporal biogeochemical cycling and ranges of atmospheric components because of their smaller reservoirs of air, water and soil, and higher concentration of biomass, and Biosphere 2 provided detailed examination and modeling of these accelerated cycles over a period of closure which measured in years. Medical research inside Biosphere 2 included the effects on humans of lowered oxygen: the discovery that human productivity can be maintained with good health with lowered atmospheric oxygen levels could lead to major economies on the design of space stations and

  3. Combined in-situ and ex-situ bioremediation of petroleum hydrocarbon contaminated soils by closed-loop soil vapor extraction and air injection

    International Nuclear Information System (INIS)

    Hu, S.S.; Buckler, M.J.

    1993-01-01

    Treatment and restoration of petroleum hydrocarbon contaminated soils at a bulk petroleum above-ground storage tank (AST) site in Michigan is being conducted through in-situ and ex-situ closed-loop soil vapor extraction (SVE), soil vapor treatment, and treated air injection (AI) processes. The soil vapor extraction process applies a vacuum through the petroleum hydrocarbon affected soils in the ex-situ bio-remediation pile (bio-pile) and along the perimeter of excavated area (in-situ area) to remove the volatile or light petroleum hydrocarbons. This process also draws ambient air into the ex-situ bio-pile and in-situ vadose zone soil along the perimeter of excavated area to enhance biodegradation of light and heavy petroleum hydrocarbons in the soil. The extracted soil vapor is treated using a custom-designed air bio-remediation filter (bio-filter) to degrade the petroleum hydrocarbon compounds in the soil vapor extraction air streams. The treated air is then injected into a flush grade soil bed in the backfill area to perform final polishing of the air stream, and to form a closed-loop air flow with the soil vapor extraction perforated pipes along the perimeter of the excavated area

  4. Soil Labile Organic Matter under Long-term Crop Rotation System

    Science.gov (United States)

    Saljnikov, E.

    2009-04-01

    Temperate grassland soils, typically Mollisols, have remained agriculturally productive with limited inputs for many years, despite the mining of energy and nutrients reserves contained within the soil organic fraction (Janzen, 1987; Tiessen et al., 1994). Such system can be considered resilient, at least initially, but one must question for how long such systems can be sustained. Effect of long-term land-use on biologically active fractions of soil organic matter is not well understood. Investigations were conducted in more than 40-year static experiments in northern Kazakhstan. We examined five fallow-wheat (Triticum aestivum L.) cropping systems with different frequencies of the fallow phase: continuous wheat (CW), 6-y rotation (6R), 4-y rotation (4R), 2-y rotation (2R) and continuous fallow (CF). A unique sample from nationally protected virgin steppe near the experimental field was sampled for comparison with long-term cultivated soils. Soil samples were collected from the two phases of each rotation, pre- and post-fallow, and analyzed for biological soil properties that are potentially mineralizable C (PMC), potentially mineralizable N (PMN), microbial biomass C (MBC) and N (MBN) and "light fraction" C (LFC) and N (LFN). Potentially mineralizable C was inversely proportional to the frequency of fallow and was highest in CW. Potentially mineralizable N was more responsive to rotation phase than other indices of SOM. Light fraction OM was negatively correlated to the frequency of fallow and was higher in pre-fallow than in post-fallow phases. All studied biological characteristics were drastically greater in the soil from the natural steppe. The results suggested that the yearly input of plant residues in a less frequently fallowed system built up more PMC, whereas PMN was closely correlated to recent inputs of substrate added as plant residue. We concluded that a frequent fallowing for long period may deplete SOM via accelerated mineralization. The results may

  5. Phosphorus in soil treatment systems: accumulation and mobility.

    Science.gov (United States)

    Eveborn, David; Gustafsson, Jon Petter; Elmefors, Elin; Yu, Lin; Eriksson, Ann-Kristin; Ljung, Emelie; Renman, Gunno

    2014-11-01

    Septic tanks with subsequent soil treatment systems (STS) are a common treatment technique for domestic wastewater in rural areas. Phosphorus (P) leakage from such systems may pose a risk to water quality (especially if they are located relatively close to surface waters). In this study, six STS in Sweden (11-28 years old) were examined. Samples taken from the unsaturated subsoil beneath the distribution pipes were investigated by means of batch and column experiments, and accumulated phosphorus were characterized through X-ray absorption near edge structure (XANES) analysis. At all sites the wastewater had clearly influenced the soil. This was observed through decreased pH, increased amounts of oxalate extractable metals and at some sites altered P sorption properties. The amount of accumulated P in the STS were found to be between 0.32 and 0.87 kg m(-3), which in most cases was just a fraction of the estimated P load (<30%). Column studies revealed that high P concentrations (up to 6 mg L(-1)) were leached from the material when deionized water was applied. However, the response to deionized water varied between the sites. As evidenced by XANES analysis, aluminium phosphates or P adsorbed to aluminium (hydr)oxides, as well as organically bound P, were important sinks for P. Generally soils with a high content of oxalate-extractable Al were also less vulnerable to P leakage. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Fitting maize into sustainable cropping systems on acid soils of the tropics

    International Nuclear Information System (INIS)

    Horst, W.J.

    2000-01-01

    One of the key elements of sustainable cropping systems is the integration of crops and/or crop cultivars with high tolerance of soil acidity and which make most efficient use of the nutrients supplied by soil and fertilizer. This paper is based mainly on on-going work within an EU-funded project combining basic research on plant adaptation mechanisms by plant physiologists, and field experimentation on acid soils in Brazil, Cameroon, Colombia and Guadeloupe by breeders, soil scientists and a agronomists. The results suggest that large genetic variability exists in adaptation of plants to acid soils. A range of morphological and physiological plant characteristics contribute to tolerance of acid soils, elucidation of which has contributed to the development of rapid techniques for screening for tolerance. Incorporation of acid-soil-tolerant species and cultivars into cropping systems contributes to improved nutrient efficiency overall, and thus reduces fertilizer needs. This may help to minimize maintenance applications of fertiliser through various pathways: (i) deeper root growth resulting in more-efficient uptake of nutrients from the sub-soil and less leaching, (ii) more biomass production resulting in less seepage and less leaching, with more intensive nutrient cycling, maintenance of higher soil organic-matter content, and, consequently, less erosion owing to better soil protection by vegetation and mulch. (author)

  7. A Computational Model of Water Migration Flux in Freezing Soil in a Closed System%封闭系统正冻土水流的一个计算模型

    Institute of Scientific and Technical Information of China (English)

    裘春晗

    2005-01-01

    A computational model of water migration flux of fine porous soil in frost heave was investigated in a closed system. The model was established with the heat-mass conservation law and from some previous experimental results. Through defining an auxiliary function an empirical function in the water migration flux, which is difficult to get, was replaced. The data needed are about the water content along the soil column after test with enough long time. We adopt the test data of sample soil columns in [1] to verify the model. The result shows it can reflect the real situation on the whole.

  8. Effects of root pruning on the growth and rhizosphere soil characteristics of short-rotation closed-canopy poplar

    Energy Technology Data Exchange (ETDEWEB)

    Du, Z. Y.; Xing, S. J.; Ma, B. Y.; Liu, F. C.; Ma, H. L.; Wang, Q. H.

    2012-11-01

    When poplar trees planted at a high density are canopy-closed in plantation after 4-5 years of growth, the roots of adjacent trees will inevitably intermingle together, which possibly restricts the nutrient uptake by root system. Root pruning might stimulate the emergence of fine roots and benefit the tree growth of short-rotation poplar at the stage of canopy closing. The aim of this study is to evaluate the effects of root pruning on DBH (diameter at breast height, 1.3 m), tree height, nutrients (N, P and K) and hormones (indoleacetic acid and cytokinin) in poplar leaves, gas exchange variables (photosynthetic rate and stomatal conductance), and rhizosphere soil characteristics. Field experiment was carried out with four-yearold poplar (Populus × euramericana cv. ‘Neva’) planted in a fluvo-aquic loam soil in Shandong province, China in early April, 2008. Three root pruning treatments (severe, moderate and light degree) were conducted at the distances of 6, 8 and 10 times DBH on both inter-row sides of the trees to the depth of 30 cm, respectively. The results showed that the growth performance was obtained in the following order of treatments: moderate > light = control > severe. In the rhizophere soil, moderate and light pruning increased the microbial populations, enzymatic activities, and the concentrations of available N, P, K and organic matter. Generally, root pruning to improve tree growth and rhizosphere soil fertility can be recommended in canopy-closed poplar plantation. The appropriate selection of root pruning intensity is a pivotal factor for the effectiveness of this technique. (Author) 35 refs.

  9. A complete closed loop control system for MNSR

    International Nuclear Information System (INIS)

    Wang Liyu

    1988-01-01

    The MNSR (Miniature Neutron Source Reactor), a 27 kW reactor, was built in 1984 in the Institute of Atomic Energy, Beijing, China. A microcomputer closed-loop control system has been developed for the MNSR using an IBM PC-XT. This system not only controls the reactor, but it is also a data acquisition system and a reactivity monitor for the reactor. A closed-loop control system can be used for reactors such as the MNSR, in which the power is self-limited and the reactivity is limited to less than 5mk (∼0.7$). As a data acquisition system or a reactivity monitor, it is applicable for any nuclear reactor. This paper describes the hardware and software in detail. 4 refs, 11 figs

  10. Technical Review of the Laboratory Biosphere Closed Ecological System Facility

    Science.gov (United States)

    Dempster, W.; van Thillo, M.; Alling, A.; Allen, J.; Silverstone, S.; Nelson, M.

    The "Laboratory Biosphere", a new closed ecological system facility in Santa Fe, New Mexico (USA) has been constructed and became operational in May 2002. Built and operated by the Global Ecotechnics consortium (Biosphere Technologies and Biosphere Foundation with Biospheric Design Inc., and the Institute of Ecotechnics), the research apparatus for intensive crop growth, biogeochemical cycle dynamics and recycling of inedible crop biomass comprises a sealed cylindrical steel chamber and attached variable volume chamber (lung) to prevent pressures caused by the expansion and contraction of the contained air. The cylindrical growing chamber is 3.7m (12 feet) long and 3.7m (12 foot) diameter, giving an internal volume of 34 m3 (1200 ft 3 ). The two crop growth beds cover 5.5 m2, with a soil depth of 0.3m (12 inches), with 12 x 1000 watt high-pressure sodium lights capable of variable lighting of 40-70 mol per m2 per day. A small soil bed reactor in the chamber can be activated to help with metabolism of chamber trace gases. The volume of the attached variable volume chamber (lung) can range between 0-11 m3 (0-400 ft 3 ). Evapotranspired and soil leachate water are collected, combined and recycled to water the planting beds. Sampling ports enable testing of water quality of leachate, condensate and irrigation water. Visual inspection windows provide views of the entire interior and growing beds. The chamber is also outfitted with an airlock to minimize air exchange when people enter and work in the chamber. Continuous sensors include atmospheric CO2 and oxygen, temperature, humidity, soil moisture, light level and water levels in reservoirs. Both "sniffer" (air ports) and "sipper" (water ports) will enable collection of water or air samples for detailed analysis. This paper reports on the development of this new soil-based bioregenerative life support closed system apparatus and its technical challenges and capabilities.

  11. Study on adsorption of 60Co in soils and minerals and transportation of 60Co in bean-soil system

    International Nuclear Information System (INIS)

    Feng Yonghong; Chen Chuanqun; Wang Shouxiang; Zhang Yongxi; Sun Zhiming

    1998-02-01

    The adsorption and desorption of 60 Co in soils and minerals, and the transportation, accumulation, distribution in bean-soil system are studied. The results are as follows: (1) 60 Co was adsorbed rapidly and desorbed difficultly by soils and minerals. The order of the saturated adsorption rate and K d (distribution coefficient) of 60 Co at the balance value was: kieselguhr>paddy soil (loamy clay)>yellowish red soil>kaoline>perlite>silt-loamy soil. The order of D f (desorption factor) value was: yellowish red soil>silt-loamy soil>kaoline>perlite>paddy soil (loamy clay)>kieselguhr. The dynamic behavior of 60 Co in the soils and minerals could be described as a closed two--compartment model. (2) After 60 Co was introduced to the bean-soil system, the concentration of 60 Co in the root is about 10.4∼23.3 times of that in the stalk, and 30 times of that in the bean pod. The negative correlation between the concentration of 60 Co in the soil and depth was detected, over 90 per cent of 60 Co was retained within 6 centimeters of the surface layer, the half residual depth was 2 centimeters. An opened two-compartment model was applied to describe the behavior of 60 Co in the bean-soil system

  12. Distribution of 14C in soil and rice plants following application of 14C - parathion to soil

    International Nuclear Information System (INIS)

    Andrea, M.M. de; Ruegg, E.F.

    1983-01-01

    Amount of residues of 14 C-parathion in soil rice plants after application of the insecticide to soil were determined in four systems studied during five weeks: pots of soil with and without plants and open or enclosed by a transparent cover. Measurements of amounts volatilized and 14 CO 2 evolution from the pesticide were made in closed system without plants. The bound residues in soil and plants were also determined. Results indicated that parathion half life in a Gley Humic soil was about two weeks. Very little radiocarbon was taken up by rice plants; of this, more was found in shoots of plants enclosed, probably by collection of the volatilized material by plants. About 6% and 4% of the 14 C-parathion were found as volatilized material and 14 CO 2 , respectively after five weeks. Bound residues varied very little and reached a maximum of 22% in soil and in plants amounted to less than 2% at the final of the experiment. (Author) [pt

  13. Performance of chromatographic systems to model soil-water sorption.

    Science.gov (United States)

    Hidalgo-Rodríguez, Marta; Fuguet, Elisabet; Ràfols, Clara; Rosés, Martí

    2012-08-24

    A systematic approach for evaluating the goodness of chromatographic systems to model the sorption of neutral organic compounds by soil from water is presented in this work. It is based on the examination of the three sources of error that determine the overall variance obtained when soil-water partition coefficients are correlated against chromatographic retention factors: the variance of the soil-water sorption data, the variance of the chromatographic data, and the variance attributed to the dissimilarity between the two systems. These contributions of variance are easily predicted through the characterization of the systems by the solvation parameter model. According to this method, several chromatographic systems besides the reference octanol-water partition system have been selected to test their performance in the emulation of soil-water sorption. The results from the experimental correlations agree with the predicted variances. The high-performance liquid chromatography system based on an immobilized artificial membrane and the micellar electrokinetic chromatography systems of sodium dodecylsulfate and sodium taurocholate provide the most precise correlation models. They have shown to predict well soil-water sorption coefficients of several tested herbicides. Octanol-water partitions and high-performance liquid chromatography measurements using C18 columns are less suited for the estimation of soil-water partition coefficients. Copyright © 2012 Elsevier B.V. All rights reserved.

  14. Calibration and analysis of soil carbon efflux estimates with closed chambers at Forsmark and Laxemar

    International Nuclear Information System (INIS)

    Tagesson, Torbern

    2006-08-01

    The Forsmark and the Laxemar investigation areas are examined by the Swedish Nuclear Fuel and Waste Management Co. for a possible construction of a deep repository for nuclear waste. In the case of a future leakage of waste, the radioactive isotopes could end up in the ecosystems above the repository. The fate of the radionuclides and their possible radiological impacts are then highly determined by ecosystem carbon cycling. An important part of the carbon cycling is the soil carbon effluxes, and in the investigation areas soil carbon effluxes have been examined with the closed chamber technique. This paper is divided into two parts. Firstly, there were problems with the equipment measuring the soil carbon dioxide efflux, and the first part is a description of the problem, how it was corrected and its possible causes. The second part is a manual in how to analyse data and calculate annual estimates of soil carbon efflux. The field measurement by the EGM-4 is just an occasional estimate of the soil carbon efflux at a certain spot and at a certain point in time. To make an interpretation of the measurements, it is essential to analyse the data and to temporally extrapolate them. It is necessary to prepare the raw data for the analysis. The problems with the EGM-4 doing the measurements at the Forsmark and the Laxemar investigation area makes it necessary to correct the data taken up by this EGM-4. The data should also be separated into soil respiration and gross primary production (GPP). Soil carbon dioxide effluxes should be changed to soil carbon effluxes. Soil carbon effluxes are strongly controlled by abiotic factors; temperature is the main factor to influence soil respiration and photosynthetically active radiation (PAR) and air temperature are the main factors to influence GPP. Regression with soil respiration against temperature and with GPP against PAR or temperature can therefore be done. These equations can then be used on datasets with temperature and PAR

  15. Calibration and analysis of soil carbon efflux estimates with closed chambers at Forsmark and Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    Tagesson, Torbern (Dept. of Physical Geography and Ecosystem Analysis, Lund Univ., Lund (SE))

    2006-08-15

    The Forsmark and the Laxemar investigation areas are examined by the Swedish Nuclear Fuel and Waste Management Co. for a possible construction of a deep repository for nuclear waste. In the case of a future leakage of waste, the radioactive isotopes could end up in the ecosystems above the repository. The fate of the radionuclides and their possible radiological impacts are then highly determined by ecosystem carbon cycling. An important part of the carbon cycling is the soil carbon effluxes, and in the investigation areas soil carbon effluxes have been examined with the closed chamber technique. This paper is divided into two parts. Firstly, there were problems with the equipment measuring the soil carbon dioxide efflux, and the first part is a description of the problem, how it was corrected and its possible causes. The second part is a manual in how to analyse data and calculate annual estimates of soil carbon efflux. The field measurement by the EGM-4 is just an occasional estimate of the soil carbon efflux at a certain spot and at a certain point in time. To make an interpretation of the measurements, it is essential to analyse the data and to temporally extrapolate them. It is necessary to prepare the raw data for the analysis. The problems with the EGM-4 doing the measurements at the Forsmark and the Laxemar investigation area makes it necessary to correct the data taken up by this EGM-4. The data should also be separated into soil respiration and gross primary production (GPP). Soil carbon dioxide effluxes should be changed to soil carbon effluxes. Soil carbon effluxes are strongly controlled by abiotic factors; temperature is the main factor to influence soil respiration and photosynthetically active radiation (PAR) and air temperature are the main factors to influence GPP. Regression with soil respiration against temperature and with GPP against PAR or temperature can therefore be done. These equations can then be used on datasets with temperature and PAR

  16. Ancient Soils in a Sunburnt Country: Nutrient and Carbon Distributions in an Australian Dryland River System

    Science.gov (United States)

    McIntyre, R. E.; Grierson, P. F.; Adams, M. A.

    2005-05-01

    Riparian systems are hotspots in dryland landscapes for nutrient supply and transformation. Biogeochemical fluxes in riparian systems are closely coupled to hydrological flowpaths, which, in dryland regions, are characterised by catastrophic flooding and long periods of erratic or no flow. Re-wetting of soils stimulates soil microbial processes that drive mineralization of nutrients necessary for plant growth. We present here the first data of a 3-year research project investigating biogeochemical processes in riparian systems in the semi-arid Pilbara region of Western Australia. Spatial patterns of nitrogen, phosphorus and carbon were closely related to topographic zone (across floodplain and channels) and vegetation type. NO3- and PCi concentrations were four-fold higher in channel, bank and riparian soils than in soils of floodplain and riparian-floodplain transition zones. Nitrogen distribution was highly heterogeneous in riparian soils (NO3- CV=102%, NH4+ CV=84%) while phosphorus was particularly heterogeneous in floodplain soils (PCi CV=153%, PCo CV=266%), in comparison to other zones. Phospholipid fatty acid (PLFA) and enzymatic profiles will be used to assess microbial functional groups, combined with mineralisation experiments and stable isotope studies (15N and 13C). These data will improve understanding of biogeochemical cycling in dryland riparian systems, and contribute to improved regional management of water resources.

  17. Overestimation of closed-chamber soil CO2 effluxes at low atmospheric turbulence

    DEFF Research Database (Denmark)

    Brændholt, Andreas; Larsen, Klaus Steenberg; Ibrom, Andreas

    2017-01-01

    Soil respiration (R-s) is an important component of ecosystem carbon balance, and accurate quantification of the diurnal and seasonal variation of R-s is crucial for a correct interpretation of the response of R-s to biotic and abiotic factors, as well as for estimating annual soil CO2 efflux rates...... be eliminated if proper mixing of air is ensured, and indeed the use of fans removed the overestimation of R-s rates during low u(*). Artificial turbulent air mixing may thus provide a method to overcome the problems of using closed-chamber gas-exchange measurement techniques during naturally occurring low...

  18. Microbial Indicators of Soil Quality under Different Land Use Systems in Subtropical Soils

    Science.gov (United States)

    Maharjan, M.

    2016-12-01

    Land-use change from native forest to intensive agricultural systems can negatively impact numerous soil parameters. Understanding the effects of forest ecosystem transformations on markers of long-term soil health is particularly important in rapidly developing regions such as Nepal, where unprecedented levels of agriculturally-driven deforestation have occurred in recent decades. However, the effects of widespread land use changes on soil quality in this region have yet to be properly characterized. Microbial indicators (soil microbial biomass, metabolic quotient and enzymes activities) are particularly suited to assessing the consequences of such ecosystem disturbances, as microbial communities are especially sensitive to environmental change. Thus, the aim of this study was to assess the effect of land use system; i.e. forest, organic and conventional farming, on soil quality in Chitwan, Nepal using markers of microbial community size and activity. Total organic C and N contents were higher in organic farming compared with conventional farming and forest, suggesting higher nutrient retention and soil preservation with organic farming practices compared to conventional. These differences in soil composition were reflected in the health of the soil microbial communities: Organic farm soil exhibited higher microbial biomass C, elevated β-glucosidase and chitinase activities, and a lower metabolic quotient relative to other soils, indicating a larger, more active, and less stressed microbial community, respectively. These results collectively demonstrate that application of organic fertilizers and organic residues positively influence nutrient availability, with subsequent improvements in soil quality and productivity. Furthermore, the sensitivity of microbial indicators to different management practices demonstrated in this study supports their use as effective markers of ecosystem disturbance in subtropical soils.

  19. Evaluation and comparison of closed-loop wash-water system

    International Nuclear Information System (INIS)

    Whitney, P.M.; Greer, C.R.

    1991-01-01

    Effluent from vehicle and equipment cleaning is known to contain a variety of potential pollutants, the most common being hydrocarbons and suspended solids. Proper treatment and discharge of this effluent is a growing concern as environmental awareness increases. In the United States, discharge of this effluent to municipal sewage treatment systems requires a permit from local authorities, discharge to surface waters requires a federal permit and, in most cases, discharge to the ground in prohibited. Furthermore, discharge to ground and surface waters can cause soil or groundwater contamination resulting in property devaluation, adverse impact on human health, fines from regulatory agencies, expensive cleanup and negative publicity. Effluent from vehicle washing typically does not meet the minimum pollutant levels allowed by regulatory agencies for discharge to surface waters or sewage treatment plants. Because of the liability associated with discharge to ground and surface waters and the difficulty in meeting municipal sewer discharge permit requirements, closed-loop wastewater treatment is an attractive alternative to discharge. Evaluation and comparison of systems from each category constitute the basis of this paper. Factors involved in selecting a system and available water-treatment technologies are discussed. The conclusion summarizes the results of the system comparison and makes recommendations for selecting and installing closed-loop water treatment systems for vehicle and equipment cleaning

  20. Long‐Term Monitoring of a Geosynthetic Reinforced Soil Integrated Bridge System (GRS‐IBS)

    Science.gov (United States)

    2017-11-01

    The geosynthetic reinforced soil integrated bridge system (GRS-IBS) is an innovative alternative to conventional bridge technology that utilizes closely spaced layers of geosynthetic reinforcement and compacted granular fill material to provide direc...

  1. Soil chemical sensor and precision agricultural chemical delivery system and method

    Science.gov (United States)

    Colburn, Jr., John W.

    1991-01-01

    A real time soil chemical sensor and precision agricultural chemical delivery system includes a plurality of ground-engaging tools in association with individual soil sensors which measure soil chemical levels. The system includes the addition of a solvent which rapidly saturates the soil/tool interface to form a conductive solution of chemicals leached from the soil. A multivalent electrode, positioned within a multivalent frame of the ground-engaging tool, applies a voltage or impresses a current between the electrode and the tool frame. A real-time soil chemical sensor and controller senses the electrochemical reaction resulting from the application of the voltage or current to the leachate, measures it by resistivity methods, and compares it against pre-set resistivity levels for substances leached by the solvent. Still greater precision is obtained by calibrating for the secondary current impressed through solvent-less soil. The appropriate concentration is then found and the servo-controlled delivery system applies the appropriate amount of fertilizer or agricultural chemicals substantially in the location from which the soil measurement was taken.

  2. Probabilistic frequency variations of structure-soil systems

    International Nuclear Information System (INIS)

    Hamilton, C.W.; Hadjian, A.H.

    1976-01-01

    During earthquakes, structure-soil systems act as filters greatly amplifying the response of equipment whose frequencies are at or near their natural frequencies. Thus, the estimation of these structure-soil system frequencies assumes significant importance both for safety and cost. Actual in-situ frequencies of structures differ from calculated frequencies due both to variations in mathematical modelling techniques and to variations of material properties. This paper studies the second source only. This variability is usually gauged by the 'worst case' analyses technique in which extreme high- and low- parameter values are assumed and the associated frequencies are used as upper and lower bounds. This approach is not entirely satisfactory because it does not provide any indication of the probability of these limits being exceeded, of the distribution between these limits, or of the level of conservation introduced into the design process. The present approach provides this additional information. The emphasis in this part is both on developing the methodology and on the results obtained. It covers both the fixed-base structure and the effects of soil-structure interaction. Empirical data on concrete proerties were obtained from previously published results. Much less is known about variability of soil properties, so the soil structure interaction coefficients are assumed to be normally distributed. As data on the variation of soil properties become available, they can be readily incorporated via the methodology developed here. (Auth.)

  3. Building an End-to-end System for Long Term Soil Monitoring

    Science.gov (United States)

    Szlavecz, K.; Terzis, A.; Musaloiu-E., R.; Cogan, J.; Szalay, A.; Gray, J.

    2006-05-01

    We have developed and deployed an experimental soil monitoring system in an urban forest. Wireless sensor nodes collect data on soil temperature, soil moisture, air temperature, and light. Data are uploaded into a SQL Server database, where they are calibrated and reorganized into an OLAP data cube. The data are accessible on-line using a web services interface with various visual tools. Our prototype system of ten nodes has been live since Sep 2005, and in 5 months of operation over 6 million measurements have been collected. At a high level, our experiment was a success: we detected variations in soil condition corresponding to topography and external environmental parameters as expected. However, we encountered a number of challenging technical problems: need for low-level programming at multiple levels, calibration across space and time, and cross- reference of measurements with external sources. Based upon the experience with this system we are now deploying 200 mode nodes with close to a thousand sensors spread over multiple sites in the context of the Baltimore Ecosystem Study LTER. www

  4. Molecular mechanisms underlying the close association between soil Burkholderia and fungi

    Science.gov (United States)

    Stopnisek, Nejc; Zühlke, Daniela; Carlier, Aurélien; Barberán, Albert; Fierer, Noah; Becher, Dörte; Riedel, Katharina; Eberl, Leo; Weisskopf, Laure

    2016-01-01

    Bacterial species belonging to the genus Burkholderia have been repeatedly reported to be associated with fungi but the extent and specificity of these associations in soils remain undetermined. To assess whether associations between Burkholderia and fungi are widespread in soils, we performed a co-occurrence analysis in an intercontinental soil sample collection. This revealed that Burkholderia significantly co-occurred with a wide range of fungi. To analyse the molecular basis of the interaction, we selected two model fungi frequently co-occurring with Burkholderia, Alternaria alternata and Fusarium solani, and analysed the proteome changes caused by cultivation with either fungus in the widespread soil inhabitant B. glathei, whose genome we sequenced. Co-cultivation with both fungi led to very similar changes in the B. glathei proteome. Our results indicate that B. glathei significantly benefits from the interaction, which is exemplified by a lower abundance of several starvation factors that were highly expressed in pure culture. However, co-cultivation also gave rise to stress factors, as indicated by the increased expression of multidrug efflux pumps and proteins involved in oxidative stress response. Our data suggest that the ability of Burkholderia to establish a close association with fungi mainly lies in the capacities to utilize fungal-secreted metabolites and to overcome fungal defense mechanisms. This work indicates that beneficial interactions with fungi might contribute to the survival strategy of Burkholderia species in environments with sub-optimal conditions, including acidic soils. PMID:25989372

  5. Molecular mechanisms underlying the close association between soil Burkholderia and fungi.

    Science.gov (United States)

    Stopnisek, Nejc; Zühlke, Daniela; Carlier, Aurélien; Barberán, Albert; Fierer, Noah; Becher, Dörte; Riedel, Katharina; Eberl, Leo; Weisskopf, Laure

    2016-01-01

    Bacterial species belonging to the genus Burkholderia have been repeatedly reported to be associated with fungi but the extent and specificity of these associations in soils remain undetermined. To assess whether associations between Burkholderia and fungi are widespread in soils, we performed a co-occurrence analysis in an intercontinental soil sample collection. This revealed that Burkholderia significantly co-occurred with a wide range of fungi. To analyse the molecular basis of the interaction, we selected two model fungi frequently co-occurring with Burkholderia, Alternaria alternata and Fusarium solani, and analysed the proteome changes caused by cultivation with either fungus in the widespread soil inhabitant B. glathei, whose genome we sequenced. Co-cultivation with both fungi led to very similar changes in the B. glathei proteome. Our results indicate that B. glathei significantly benefits from the interaction, which is exemplified by a lower abundance of several starvation factors that were highly expressed in pure culture. However, co-cultivation also gave rise to stress factors, as indicated by the increased expression of multidrug efflux pumps and proteins involved in oxidative stress response. Our data suggest that the ability of Burkholderia to establish a close association with fungi mainly lies in the capacities to utilize fungal-secreted metabolites and to overcome fungal defense mechanisms. This work indicates that beneficial interactions with fungi might contribute to the survival strategy of Burkholderia species in environments with sub-optimal conditions, including acidic soils.

  6. Atrazine and Diuron partitioning within a soil-water-surfactant system

    Science.gov (United States)

    Wang, P.; Keller, A.

    2006-12-01

    The interaction between pesticide and soil and water is even more complex in the presence of surfactants. In this study, batch equilibrium was employed to study the sorption of surfactants and the partitioning behaviors of Atrazine and Diuron within a soil-water-surfactant system. Five soils and four surfactants (nonionic Triton- 100, cationic Benzalkonium Chloride (BC), anionic Linear Alkylbenzenesulfonate (LAS), and anionic Sodium Dodecyl Sulfate (SDS)) were used. All surfactant sorption isotherms exhibited an initial linear increase at low surfactant concentrations but reached an asymptotic value as the surfactant concentrations increased. Among the surfactants, BC had the highest sorption onto all soils, followed by Triton-100 and then by LAS and SDS, implying that the nature of the charge significantly influences surfactant sorption. Sorption of either Triton-100 or BC was highly correlated with soil Cation Exchange Capacity (CEC) while that of LAS and SDS was complicated by the presence of Ca2+ and Mg2+ in the aqueous phase and the CEC sites. Both LAS and SDS formed complexes with Ca2+ and Mg2+, resulting in a significant decrease in the detergency of the surfactants. At high surfactant concentrations and with micelles present in the aqueous phase, the micelles formed a more competitive partitioning site for the pesticides, resulting in less pesticide sorbed to the soil. At low Triton-100 and BC concentration, the sorption of the surfactants first resulted in less Atrazine sorption but more Diuron sorption, implying competition between the surfactants and Atrazine, which serves as an indirect evidence that there is a different sorption mechanism for Atrazine. Atrazine is a weak base and it protonates and becomes positively charged near particle surfaces where the pH is much lower than in the bulk solution. The protonated Atrazine may then be held on the CEC sites via electrostatic attraction. Triton-100, LAS and SDS sorbed on the soil showed similar

  7. Linking soil systems to societal value systems

    Science.gov (United States)

    Helming, Katharina; Daedlow, Katrin; Techen, Anja; Kaiser, David Brian

    2017-04-01

    Sustainable management of soils is needed to avoid soil degradation and to maintain soil functions. This requires the assessment of how human activities drive soil management, how soil management affect soil functions and soil degradation, which trade-offs occur and how they compromise sustainable development targets. In the frame of the German research programme "Soils as a sustainable resource for the bio-economy - BonaRes", we developed an enhanced approach of the DPSIR (driver-pressure-state-impact-response) cycle which helps to assess these interrelations. Because not all soil functions can be maximized simultaneously in space and time and trade-offs are inevitable, it depends on the societal value system to decide which management practices and respective soil functional performances are valued sustainably. We analysed the applicability of three valuation concepts being prominent in research about social-ecological systems, namely resource efficiency, ecosystem services, and ethics and equity. The concept of resource efficiency is based in the life-cycle thinking and is often applied at the level of the farming systems and in the context of bio-economy strategies. It covers the use of natural (water, energy, nutrients, land) and economic resources. At the landscape level, the concept of ecosystem services is prominent. Here, the contribution of soils to the provisioning, regulating and cultural services of the natural ecosystems is considered. Ethical considerations include the intrinsic values of nature as well as issues of local and global equity between different societal groups, generations, and localities. The three concepts cover different problem dimensions and complexity levels of soil management and decision making. Alone, none of them are capable to discover complex questions of sustainable soil management and development. Rather, the exact spatial and temporal framing of the sustainability problem at stake determines which combination of the value

  8. TRADITIONAL CANISTER-BASED OPEN WASTE MANAGEMENT SYSTEM VERSUS CLOSED SYSTEM: HAZARDOUS EXPOSURE PREVENTION AND OPERATING THEATRE STAFF SATISFACTION.

    Science.gov (United States)

    Horn, M; Patel, N; MacLellan, D M; Millard, N

    2016-06-01

    Exposure to blood and body fluids is a major concern to health care professionals working in operating rooms (ORs). Thus, it is essential that hospitals use fluid waste management systems that minimise risk to staff, while maximising efficiency. The current study compared the utility of a 'closed' system with a traditional canister-based 'open' system in the OR in a private hospital setting. A total of 30 arthroscopy, urology, and orthopaedic cases were observed. The closed system was used in five, four, and six cases, respectively and the open system was used in nine, two, and four cases, respectively. The average number of opportunities for staff to be exposed to hazardous fluids were fewer for the closed system when compared to the open during arthroscopy and urology procedures. The open system required nearly 3.5 times as much staff time for set-up, maintenance during procedures, and post-procedure disposal of waste. Theatre staff expressed greater satisfaction with the closed system than with the open. In conclusion, compared with the open system, the closed system offers a less hazardous and more efficient method of disposing of fluid waste generated in the OR.

  9. Heap leaching of Cu contaminated soil with [S,S]-EDDS in a closed process loop

    International Nuclear Information System (INIS)

    Finzgar, Neza; Zumer, Alenka; Lestan, Domen

    2006-01-01

    Heap leaching of Cu contaminated soil (412 ± 11 mg kg -1 ) with 5 mmol kg -1 ethylenediamine disuccinate [S,S]-EDDS as a chelator was tested in a laboratory-scale soil column study. The washing solution was recycled in a closed process loop after microbial (using a microbially active permeable bed, composed of substrate and absorbent) and oxidative chemical (using combined ozonation and UV irradiation) degradation of metal-[S,S]-EDDS complexes and retention of released Cu on a commercial absorbent Slovakite. Heap leaching using the permeable bed removed 25.5 ± 3.6% of initial total Cu from the soil. Ozone/UV treatment of the [S,S]-EDDS washing solution removed much more, 47.5 ± 7.4%, of Cu. Both methods yielded a clear and colorless final (waste) washing solution, with 7.0 ± 10.0 and 2.6 ± 0.7 mg L -1 Cu (permeable bed and ozone/UV method, respectively). The results of our study indicate that chemical treatment of chelator washing solution with ozone/UV in a closed process loop could lead to the development of a new, efficient and environmentally safe remediation method with controllable Cu emissions

  10. Identification of soil P fractions that are associated with P loss from surface runoff under various cropping systems and fertilizer rates on sloped farmland.

    Science.gov (United States)

    Li, Xinghua; Wang, Baona; Yang, Tewu; Zhu, Duanwei; Nie, Zhongnan; Xu, Junchi

    2017-01-01

    Soil phosphorus (P) fractions and runoff P concentration were measured to understand the fate of soil P entering surface runoff water during summer cropping season of different double cropping systems under two fertilizer regimes. The dominant form of runoff P was particulate P (PP). Runoff total P (TP) was higher at the vegetative growth stage and lower at the crop reproductive stage. TP and PP were derived mainly from soil Olsen-P, Al-P and Fe-P and amounts increased with sediment content in runoff water. Runoff P discharge was closely related to the changes in soil P forms. Soil Olsen-P, mainly consisting of some Ca2-P and Al-P, was increased by elevating fertilizer rate. Along with crop growth, there were active interconversions among Olsen-P, Org-P, Fe-P and O-Al-P in the soil, and some available P converted into Ca10-P, with O-Fe-P possibly being a transitional form for this conversion. The oilseed rape/corn system had less runoff TP at the early stage, and wheat/sweet potato system had a lower runoff P at the late stage. Intercropping corn with sweet potato in the field with oilseed rape as a previous crop may be helpful for alleviating runoff P load during the summer in this region.

  11. Identification of soil P fractions that are associated with P loss from surface runoff under various cropping systems and fertilizer rates on sloped farmland.

    Directory of Open Access Journals (Sweden)

    Xinghua Li

    Full Text Available Soil phosphorus (P fractions and runoff P concentration were measured to understand the fate of soil P entering surface runoff water during summer cropping season of different double cropping systems under two fertilizer regimes. The dominant form of runoff P was particulate P (PP. Runoff total P (TP was higher at the vegetative growth stage and lower at the crop reproductive stage. TP and PP were derived mainly from soil Olsen-P, Al-P and Fe-P and amounts increased with sediment content in runoff water. Runoff P discharge was closely related to the changes in soil P forms. Soil Olsen-P, mainly consisting of some Ca2-P and Al-P, was increased by elevating fertilizer rate. Along with crop growth, there were active interconversions among Olsen-P, Org-P, Fe-P and O-Al-P in the soil, and some available P converted into Ca10-P, with O-Fe-P possibly being a transitional form for this conversion. The oilseed rape/corn system had less runoff TP at the early stage, and wheat/sweet potato system had a lower runoff P at the late stage. Intercropping corn with sweet potato in the field with oilseed rape as a previous crop may be helpful for alleviating runoff P load during the summer in this region.

  12. The 134Cs uptake by sunflower (Helianthus anuus, Less) cultivated on soil contaminated with 134Cs

    International Nuclear Information System (INIS)

    Poppy Intan Tjahaja; Putu Sukmabuana

    2008-01-01

    One of the methods for remediation of contaminated environment is phytoremediation techniques, i.e. the environmental remediation using plants. In this research the bioavailability of sunflower plant (Helianthus anuus, Less) in radiocaesium uptake from soil was studied for being considered as a phytoremediator later. Sunflower plants were cultivated on soil contaminated with 134 Cs with the concentrations of 29,3 kBq/kg ; 117,2 kBq/kg ; 557 kBq/kg for 45 days. As control the sunflowers were also cultivated on non contaminated soil. Observation was carried out every 5 days by sampling 3 plants and soils. The plant and soil samples were dried using infra red lamp for 24 hours, and then counted using gamma spectrometer. The counting results i.e. 134 Cs concentration on soil and plant parts were then analyzed to obtain transfer factor (TF) values. The highest TF values was reached on 26 th day, i.e. 0,87; 1,89 ; 2,82 for initial soil 134 Cs concentrations of 29,3 Bq/g ; 117,2 Bq/g ; 557 Bq/g, respectively. The TF values obtained expressed the capability of plants to accumulate 134 Cs from soils. The observation to the plants growth showed that the plants grew normally on the 134 Cs contaminated soil until the concentration of 557 Bq/g. The sunflower can be considered to be phytoremediator of andosol soil contaminated with Cs radionuclides. (author)

  13. Automatic systems for opening and closing reactor vessels, steam generators, and pressurizers

    International Nuclear Information System (INIS)

    Samblat, C.

    1990-01-01

    The need for shorter working assignments, reduced dose rates and less time consumption have caused Electricite de France and Framatome to automate the entire procedure of opening and closing the main components in the primary system, such as the reactor vessel, steam generator, and pressurizer. The experience accumulated by the two companies in more than 300 annual revisions of nuclear generating units worldwide has been used as a basis for automating all bolt opening and closing steps as well as cleaning processes. The machines and automatic systems currently in operation are the result of extensive studies and practical tests. (orig.) [de

  14. Microbiota of radish plants, cultivated in closed and open ecological systems

    Science.gov (United States)

    Tirranen, L. S.

    It is common knowledge that microorganisms respond to environmental changes faster than other representatives of the living world. The major aim of this work was to examine and analyze the characteristics of the microbiota of radish culture, cultivated in the closed ecological system of human life-support Bios-3 and in an open system in different experiments. Microbial community of near-root, root zone and phyllosphere of radish were studied at the phases of seedlings, root formation, technical ripeness—by washing-off method—like microbiota of the substrate (expanded clay aggregate) and of the seeds of radish culture. Inoculation on appropriate media was made to count total quantity of anaerobic and aerobic bacteria, bacteria of coliform group, spore-forming, Proteus group, fluorescent, phytopathogenic bacteria, growing on Fermi medium, yeasts, microscopic fungi, Actinomyces. It was revealed that formation of the microbiota of radish plants depends on the age, plant cultivation technology and the specific conditions of the closed system. Composition of microbial conveyor-cultivated in phytotrons varied in quality and in quantity with plant growth phases—in the same manner as cultivation of even-aged soil and hydroponics monocultures which was determined by different qualitative and quantitative composition of root emissions in the course of plant vegetation. The higher plant component formed its own microbial complex different from that formed prior to closure. The microbial complex of vegetable polyculture is more diverse and stable than the monoculture of radish. We registered the changes in the species composition and microorganism quantity during plant cultivation in the closed system on a long-used solution. It was demonstrated that during the short-term (7 days) use of the nutrient solution in the experiments without system closing, the species composition of the microbiota of radish plants was more diverse in a multiple-aged vegetable polyculture (61

  15. Ecological intensification of cereal production systems: yield potential, soil quality, and precision agriculture.

    Science.gov (United States)

    Cassman, K G

    1999-05-25

    Wheat (Triticum aestivum L.), rice (Oryza sativa L.), and maize (Zea mays L.) provide about two-thirds of all energy in human diets, and four major cropping systems in which these cereals are grown represent the foundation of human food supply. Yield per unit time and land has increased markedly during the past 30 years in these systems, a result of intensified crop management involving improved germplasm, greater inputs of fertilizer, production of two or more crops per year on the same piece of land, and irrigation. Meeting future food demand while minimizing expansion of cultivated area primarily will depend on continued intensification of these same four systems. The manner in which further intensification is achieved, however, will differ markedly from the past because the exploitable gap between average farm yields and genetic yield potential is closing. At present, the rate of increase in yield potential is much less than the expected increase in demand. Hence, average farm yields must reach 70-80% of the yield potential ceiling within 30 years in each of these major cereal systems. Achieving consistent production at these high levels without causing environmental damage requires improvements in soil quality and precise management of all production factors in time and space. The scope of the scientific challenge related to these objectives is discussed. It is concluded that major scientific breakthroughs must occur in basic plant physiology, ecophysiology, agroecology, and soil science to achieve the ecological intensification that is needed to meet the expected increase in food demand.

  16. Intensive agriculture reduces soil biodiversity across Europe.

    Science.gov (United States)

    Tsiafouli, Maria A; Thébault, Elisa; Sgardelis, Stefanos P; de Ruiter, Peter C; van der Putten, Wim H; Birkhofer, Klaus; Hemerik, Lia; de Vries, Franciska T; Bardgett, Richard D; Brady, Mark Vincent; Bjornlund, Lisa; Jørgensen, Helene Bracht; Christensen, Sören; Hertefeldt, Tina D'; Hotes, Stefan; Gera Hol, W H; Frouz, Jan; Liiri, Mira; Mortimer, Simon R; Setälä, Heikki; Tzanopoulos, Joseph; Uteseny, Karoline; Pižl, Václav; Stary, Josef; Wolters, Volkmar; Hedlund, Katarina

    2015-02-01

    Soil biodiversity plays a key role in regulating the processes that underpin the delivery of ecosystem goods and services in terrestrial ecosystems. Agricultural intensification is known to change the diversity of individual groups of soil biota, but less is known about how intensification affects biodiversity of the soil food web as a whole, and whether or not these effects may be generalized across regions. We examined biodiversity in soil food webs from grasslands, extensive, and intensive rotations in four agricultural regions across Europe: in Sweden, the UK, the Czech Republic and Greece. Effects of land-use intensity were quantified based on structure and diversity among functional groups in the soil food web, as well as on community-weighted mean body mass of soil fauna. We also elucidate land-use intensity effects on diversity of taxonomic units within taxonomic groups of soil fauna. We found that between regions soil food web diversity measures were variable, but that increasing land-use intensity caused highly consistent responses. In particular, land-use intensification reduced the complexity in the soil food webs, as well as the community-weighted mean body mass of soil fauna. In all regions across Europe, species richness of earthworms, Collembolans, and oribatid mites was negatively affected by increased land-use intensity. The taxonomic distinctness, which is a measure of taxonomic relatedness of species in a community that is independent of species richness, was also reduced by land-use intensification. We conclude that intensive agriculture reduces soil biodiversity, making soil food webs less diverse and composed of smaller bodied organisms. Land-use intensification results in fewer functional groups of soil biota with fewer and taxonomically more closely related species. We discuss how these changes in soil biodiversity due to land-use intensification may threaten the functioning of soil in agricultural production systems. © 2014 John Wiley

  17. Effects of different agricultural systems on soil quality in Northern Limón province, Costa Rica

    Directory of Open Access Journals (Sweden)

    Emma Cornwell

    2014-09-01

    Full Text Available Conversion of native rainforest ecosystems in Limón Province of Costa Rica to banana and pineapple monoculture has led to reductions in biodiversity and soil quality. Agroforestry management of cacao (Theobroma cacao is an alternative system that may maintain the agricultural livelihood of the region while more closely mimicking native ecosystems. This study compared physical, biological and chemical soil quality indicators of a cacao plantation under organic agroforestry management with banana, pineapple, and pasture systems; a native forest nearby served as a control. For bulk density and earthworm analysis, 18 samples were collected between March and April 2012 from each ecosystem paired with 18 samples from the cacao. Cacao had a lower bulk density than banana and pineapple monocultures, but greater than the forest (p<0.05. Cacao also hosted a greater number and mass of earthworms than banana and pineapple (p<0.05, but similar to forest and pasture. For soil chemical characteristics, three composite samples were collected in March 2012 from each agroecosystem paired with three samples from the cacao plantation. Forest and pineapple ecosystems had the lowest pH, cation exchange capacity, and exchangeable nutrient cations, while cacao had the greatest (p<0.05. Total nutrient levels of P and N were slightly greater in banana, pineapple and pasture than in cacao; probably related to addition of chemical fertilizer and manure from cattle grazing. Forest and cacao also had greater %C, than other ecosystems, which is directly related to soil organic matter content (p<0.0001. Overall, cacao had more favorable physical, biological and chemical soil characteristics than banana and pineapple monocultures, while trends were less conclusive compared to the pastureland. While organic cacao was inferior to native forest in some soil characteristics such as bulk density and organic carbon, its soil quality did best mimic that of the native forest. This

  18. Effects of 24 Years of Conservation Tillage Systems on Soil Organic Carbon and Soil Productivity

    Directory of Open Access Journals (Sweden)

    Kenneth R. Olson

    2013-01-01

    Full Text Available The 24-year study was conducted in southern Illinois (USA on land similar to that being removed from Conservation Reserve Program (CRP to evaluate the effects of conservation tillage systems on: (1 amount and rates of soil organic carbon (SOC storage and retention, (2 the long-term corn and soybean yields, and (3 maintenance and restoration of soil productivity of previously eroded soils. The no-till (NT plots did store and retain 7.8 Mg C ha−1 more and chisel plow (CP −1.6 Mg C ha−1 less SOC in the soil than moldboard plow (MP during the 24 years. However, no SOC sequestration occurred in the sloping and eroding NT, CP, and MP plots since the SOC level of the plot area was greater at the start of the experiment than at the end. The NT plots actually lost a total of −1.2 Mg C ha−1, the CP lost −9.9 Mg C ha−1, and the MP lost −8.2 Mg C ha−1 during the 24-year study. The long-term productivity of NT compared favorably with that of MP and CP systems.

  19. Earth applications of closed ecological systems: relevance to the development of sustainability in our global biosphere.

    Science.gov (United States)

    Nelson, M; Allen, J; Alling, A; Dempster, W F; Silverstone, S

    2003-01-01

    The parallels between the challenges facing bioregenerative life support in artificial closed ecological systems and those in our global biosphere are striking. At the scale of the current global technosphere and expanding human population, it is increasingly obvious that the biosphere can no longer safely buffer and absorb technogenic and anthropogenic pollutants. The loss of biodiversity, reliance on non-renewable natural resources, and conversion of once wild ecosystems for human use with attendant desertification/soil erosion, has led to a shift of consciousness and the widespread call for sustainability of human activities. For researchers working on bioregenerative life support in closed systems, the small volumes and faster cycling times than in the Earth's biosphere make it starkly clear that systems must be designed to ensure renewal of water and atmosphere, nutrient recycling, production of healthy food, and safe environmental methods of maintaining technical systems. The development of technical systems that can be fully integrated and supportive of living systems is a harbinger of new perspectives as well as technologies in the global environment. In addition, closed system bioregenerative life support offers opportunities for public education and consciousness changing of how to live with our global biosphere. c2003 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

  20. Design of a Bioelectronics Hybrid System in Real Time and in Closed Loop

    Directory of Open Access Journals (Sweden)

    Sylvie Renaud

    2012-12-01

    Full Text Available Hynets, for Hybrid (living-artificial Networks, are an efficient and adaptable experimental support to explore the dynamics and the adaptation process of biological systems. We present in this paper an innovative platform performing a real-time closed-loop between a cultured network (e.g. neurons and an artificial processing (e.g. software processing or a robotic interface. The system gathers bioware, hardware, and software components and ensures the closed-loop data processing in less than 50 µs. We describe also a methodology that may help to standardize the description of some experiments. This method is associated to a full custom Graphical User Interface. We detail here the system choices, components, and performances.

  1. Can we manipulate root system architecture to control soil erosion?

    Science.gov (United States)

    Ola, A.; Dodd, I. C.; Quinton, J. N.

    2015-09-01

    Soil erosion is a major threat to soil functioning. The use of vegetation to control erosion has long been a topic for research. Much of this research has focused on the above-ground properties of plants, demonstrating the important role that canopy structure and cover plays in the reduction of water erosion processes. Less attention has been paid to plant roots. Plant roots are a crucial yet under-researched factor for reducing water erosion through their ability to alter soil properties, such as aggregate stability, hydraulic function and shear strength. However, there have been few attempts to specifically manipulate plant root system properties to reduce soil erosion. Therefore, this review aims to explore the effects that plant roots have on soil erosion and hydrological processes, and how plant root architecture might be manipulated to enhance its erosion control properties. We demonstrate the importance of root system architecture for the control of soil erosion. We also show that some plant species respond to nutrient-enriched patches by increasing lateral root proliferation. The erosional response to root proliferation will depend upon its location: at the soil surface dense mats of roots may reduce soil erodibility but block soil pores thereby limiting infiltration, enhancing runoff. Additionally, in nutrient-deprived regions, root hair development may be stimulated and larger amounts of root exudates released, thereby improving aggregate stability and decreasing erodibility. Utilizing nutrient placement at specific depths may represent a potentially new, easily implemented, management strategy on nutrient-poor agricultural land or constructed slopes to control erosion, and further research in this area is needed.

  2. Uptake of fertilizer nitrogen and soil nitrogen by rice using 15N-labelled nitrogen fertilizer

    International Nuclear Information System (INIS)

    Reddy, K.R.; Patrick, W.H. Jr.

    1980-01-01

    Data from five field experiments using labelled nitrogen fertilizer were used to determine the relative effects of soil nitrogen and fertilizer nitrogen on rice yield. Yield of grain was closely correlated with total aboveground nitrogen uptake (soil + fertilizer), less closely correlated with soil nitrogen uptake and not significantly correlated with fertilizer nitrogen uptake. When yield increase rather than yield was correlated with fertilizer nitrogen uptake, the correlation coefficient was statistically significant. (orig.)

  3. Development and research program for a soil-based bioregenerative agriculture system to feed a four person crew at a Mars base

    Science.gov (United States)

    Silverstone, S.; Nelson, M.; Alling, A.; Allen, J.

    For humans to survive during long-term missions on the Martian surface, bioregenerative life support systems including food production will decrease requirements for launch of Earth supplies, and increase mission safety. It is proposed that the development of ``modular biospheres''- closed system units that can be air-locked together and which contain soil-based bioregenerative agriculture, horticulture, with a wetland wastewater treatment system is an approach for Mars habitation scenarios. Based on previous work done in long-term life support at Biosphere 2 and other closed ecological systems, this consortium proposes a research and development program called Mars On Earth™ which will simulate a life support system designed for a four person crew. The structure will consist of /6 × 110 square meter modular agricultural units designed to produce a nutritionally adequate diet for 4 people, recycling all air, water and waste, while utilizing a soil created by the organic enrichment and modification of Mars simulant soils. Further research needs are discussed, such as determining optimal light levels for growth of the necessary range of crops, energy trade-offs for agriculture (e.g. light intensity vs. required area), capabilities of Martian soils and their need for enrichment and elimination of oxides, strategies for use of human waste products, and maintaining atmospheric balance between people, plants and soils.

  4. Development and research program for a soil-based bioregenerative agriculture system to feed a four person crew at a Mars base.

    Science.gov (United States)

    Silverstone, S; Nelson, M; Alling, A; Allen, J

    2003-01-01

    For humans to survive during long-term missions on the Martian surface, bioregenerative life support systems including food production will decrease requirements for launch of Earth supplies, and increase mission safety. It is proposed that the development of "modular biospheres"--closed system units that can be air-locked together and which contain soil-based bioregenerative agriculture, horticulture, with a wetland wastewater treatment system is an approach for Mars habitation scenarios. Based on previous work done in long-term life support at Biosphere 2 and other closed ecological systems, this consortium proposes a research and development program called Mars On Earth(TM) which will simulate a life support system designed for a four person crew. The structure will consist of 6 x 110 square meter modular agricultural units designed to produce a nutritionally adequate diet for 4 people, recycling all air, water and waste, while utilizing a soil created by the organic enrichment and modification of Mars simulant soils. Further research needs are discussed, such as determining optimal light levels for growth of the necessary range of crops, energy trade-offs for agriculture (e.g. light intensity vs. required area), capabilities of Martian soils and their need for enrichment and elimination of oxides, strategies for use of human waste products, and maintaining atmospheric balance between people, plants and soils. c2002 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

  5. Soil microorganisms determine the sorption of radionuclides within organic soil systems

    International Nuclear Information System (INIS)

    Parekh, N.R.; Poskitt, J.M.; Dodd, B.A.; Potter, E.D.; Sanchez, A.

    2008-01-01

    The potential of soil microorganisms to enhance the retention of 137 Cs and 85 Sr in organic systems was assessed in a series of experiments. A biologically active, 'mineral-free', organic material, produced under laboratory conditions from leaves, was used as the uptake matrix in all experiments to minimise potential interference from competing clay minerals. Biological uptake and release were differentiated from abiotic processes by comparing the sorption of radionuclides in sterilised organic material with sterile material inoculated with soil extracts or single fungal strains. Our results show conclusively that living components of soil systems are of primary importance in the uptake of radionuclides in organic material. The presence of soil microorganisms significantly enhanced the retention of Cs in organic systems and ∼70% of the Cs spike was strongly (irreversibly) bound (remained non-extractable) in the presence of microorganisms compared to only ∼10% in abiotic systems. Sorption of 85 Sr was not significantly influenced by the presence of soil microorganisms. A non-linear temperature response was observed for the retention in biotic systems with increased uptake at between 10 and 30 deg. C and lower retention at temperatures above or below the optimum range. The optimum temperatures for biological uptake were between 15 and 20 deg. C for Cs, and 25 and 30 deg. C for Sr. Our results indicate that single strains of soil and saprotrophic fungi make an important contribution to the sorption of Cs and Sr in organic systems, but can only account for part of the strong, irreversible binding observed in biotic systems. Single strains of soil fungi increased the amount of non-extractable 137 Cs (by ∼30%) and 85 Sr (by ∼20%) in the organic systems as compared to abiotic systems, but the major fraction of 137 Cs and 85 Sr sorbed in systems inoculated with saprotrophic fungi remained extractable

  6. Simulation of large-scale soil water systems using groundwater data and satellite based soil moisture

    Science.gov (United States)

    Kreye, Phillip; Meon, Günter

    2016-04-01

    , interfaces, and parameterisation. The demand for an automated optimisation procedure arises through the multi-variable examination of the system and its new complexity. A pioneering lexicographical strategy of optimisation was developed, using the model interfaces connected to modern data types. The employed strategy is easy to use, can be transferred to other model areas and does not require high computing times. The new strategy converges in less than 100 iterations. Established algorithms, like SCE-UA, were used by comparison. They need 500-2000 iterations. Taking runoff, soil moisture and groundwater levels as objectives, the calibration with the help of the lexicographical calibration strategy showed the following results: - For different model areas it is possible to fit the simulated runoff very well to the observation (R² ~ 0.9). - Internal system variables like soil moisture and groundwater levels are plausibly simulated and are of high quality as well (R² ~ 0.8). - During winter season a significant improvement of the quality of the simulated runoff is achieved, compared to calibrations without the objectives of soil moisture and groundwater level. This shows that the involvement of additional observation sources leads to a much higher plausibility of internal system behaviour. - Parameters that were achieved by the lexicographical calibration strategy are more plausible compared to results of the SCE-UA algorithm.

  7. Change-in-ratio density estimator for feral pigs is less biased than closed mark-recapture estimates

    Science.gov (United States)

    Hanson, L.B.; Grand, J.B.; Mitchell, M.S.; Jolley, D.B.; Sparklin, B.D.; Ditchkoff, S.S.

    2008-01-01

    Closed-population capture-mark-recapture (CMR) methods can produce biased density estimates for species with low or heterogeneous detection probabilities. In an attempt to address such biases, we developed a density-estimation method based on the change in ratio (CIR) of survival between two populations where survival, calculated using an open-population CMR model, is known to differ. We used our method to estimate density for a feral pig (Sus scrofa) population on Fort Benning, Georgia, USA. To assess its validity, we compared it to an estimate of the minimum density of pigs known to be alive and two estimates based on closed-population CMR models. Comparison of the density estimates revealed that the CIR estimator produced a density estimate with low precision that was reasonable with respect to minimum known density. By contrast, density point estimates using the closed-population CMR models were less than the minimum known density, consistent with biases created by low and heterogeneous capture probabilities for species like feral pigs that may occur in low density or are difficult to capture. Our CIR density estimator may be useful for tracking broad-scale, long-term changes in species, such as large cats, for which closed CMR models are unlikely to work. ?? CSIRO 2008.

  8. Green roof soil system affected by soil structural changes: A project initiation

    Science.gov (United States)

    Jelínková, Vladimíra; Dohnal, Michal; Šácha, Jan; Šebestová, Jana; Sněhota, Michal

    2014-05-01

    Anthropogenic soil systems and structures such as green roofs, permeable or grassed pavements comprise appreciable part of the urban watersheds and are considered to be beneficial regarding to numerous aspects (e.g. carbon dioxide cycle, microclimate, reducing solar absorbance and storm water). Expected performance of these systems is significantly affected by water and heat regimes that are primarily defined by technology and materials used for system construction, local climate condition, amount of precipitation, the orientation and type of the vegetation cover. The benefits and potencies of anthropogenic soil systems could be considerably threatened in case when exposed to structural changes of thin top soil layer in time. Extensive green roof together with experimental green roof segment was established and advanced automated monitoring system of micrometeorological variables was set-up at the experimental site of University Centre for Energy Efficient Buildings as an interdisciplinary research facility of the Czech Technical University in Prague. The key objectives of the project are (i) to characterize hydraulic and thermal properties of soil substrate studied, (ii) to establish seasonal dynamics of water and heat in selected soil systems from continuous monitoring of relevant variables, (iii) to detect structural changes with the use of X-ray Computed Tomography, (iv) to identify with the help of numerical modeling and acquired datasets how water and heat dynamics in anthropogenic soil systems are affected by soil structural changes. Achievements of the objectives will advance understanding of the anthropogenic soil systems behavior in conurbations with the temperate climate.

  9. A theory of desynchronisable closed loop system

    Directory of Open Access Journals (Sweden)

    Harsh Beohar

    2010-10-01

    Full Text Available The task of implementing a supervisory controller is non-trivial, even though different theories exist that allow automatic synthesis of these controllers in the form of automata. One of the reasons for this discord is due to the asynchronous interaction between a plant and its controller in implementations, whereas the existing supervisory control theories assume synchronous interaction. As a consequence the implementation suffer from the so-called inexact synchronisation problem. In this paper we address the issue of inexact synchronisation in a process algebraic setting, by solving a more general problem of refinement. We construct an asynchronous closed loop system by introducing a communication medium in a given synchronous closed loop system. Our goal is to find sufficient conditions under which a synchronous closed loop system is branching bisimilar to its corresponding asynchronous closed loop system.

  10. Integrated Universal Soil Loss Equation (USLE) and Geographical Information System (GIS) for Soil Erosion Measurement in basin of Asap river, Central Vietnam

    Science.gov (United States)

    Pham Gia, Tung; Degener, Jan; Kappas, Martin

    2017-04-01

    The study was conducted in Asap river basin, A Luoi district, Thua Thien Hue Province, Vietnam, using the Universal Soil Loss Equation (USLE) and Geographical Information System (GIS) to determine the soil erosion status. The results show strong effect of the heavy rainfall and high slope on the erosion level in the research area. More than 40% of land area lost over 10 tons/ha/year. The natural forest land lost the most by averagely is 38.4 tons/ha/year, while the agricultural land showed less with 2.79 tons for paddy rice land use type and 7.58 tons for upland crops yearly. Comparison between some places of Vietnam and the Southeast Asia showed that soil erosion in watersheds of Asap is more serious. We have been proposed a recommendation on changing the classification system of land use type in Vietnam for more accurate in soil erosion measurement. Keywords: Land use type, Soil erosion, USLE, Central Vietnam.

  11. Grey water treatment by the slanted soil system with unsorted soil media.

    Science.gov (United States)

    Ushijima, Ken; Tanaka, Erina; Suzuki, Laís Yuko; Hijikata, Nowaki; Funamizu, Naoyuki; Ito, Ryusei

    2015-01-01

    This study evaluated the performance of unsorted soil media in the slanted soil treatment system, in terms of removal efficiency in suspended solids (SS), chemical oxygen demand (COD), linear alkylbenzene sulphonate (LAS) and Escherichia coli, and lifetime until clogging occurs. Unsorted soil performed longer lifetime until clogging than sorted fine soil. Removal of SS, COD, and LAS also performed same or better level in unsorted soil than fine soil. As reaction coefficients of COD and LAS were described as a function of the hydraulic loading rate, we can design a slanted soil system according to the expected hydraulic loading rate and the targeted level of COD or LAS in effluent. Regarding bacteria removal, unsorted soil performed sufficient reduction of E. coli for 5 weeks; however, the removal process occurred throughout all four chambers, while that of fine soil occurred in one to two chambers.

  12. Volume reduction system by soil classifying. Soil-washing system and problems to be solved

    International Nuclear Information System (INIS)

    Oshino, Yoshio

    2016-01-01

    Radioactive contamination of ground surfaces, buildings and forests in a broad area was caused by the accident at the Fukushima Daiichi Nuclear Power Plant in Japan. The national government and municipalities have still been carrying out the decontamination works for livelihood areas after five years from the accident. The government estimated that the amounts of soils and wastes removed by the decontamination works would be about 28,000,000 cubic meters maximum including 20,000,000 cubic meters maximum of soils. The removed soils will be stored in “Interim Storage Facility” then will be finally disposed outside of Fukushima prefecture within 30 years. On the other hand, shortage of the soils as materials needed for the revitalization in Fukushima prefecture is expected. Technical Advisory Council on Remediation and Waste Management, which consists of about 90 companies, started a working group to investigate solutions to these problems. The working group focused on the investigation of the possibility to recycle the soils by washing and classification to use them as the materials for civil engineering works, and to reduce the volume of the interim storage. In the first part of this report, we have evaluated the applicability of various technologies for purification and volume reduction of the removed soils, and have researched usages, required quantities and specifications of the recycled soils. In the second part, we have made trial calculations of the volume reduction effects and costs using the washing and classification system. The calculated results showed the possibilities of reducing the storage capacity of the interim storage facility, as well as the construction and the operation costs by recycling the removed soils with the washing and classification system inside the interim storage facility. At the end of this report, we proposed problems to be solved in order to adopt the washing and classification system. (author)

  13. Active fault diagnosis in closed-loop systems

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Poulsen, Niels Kjølstad

    2005-01-01

    Active fault diagnosis (AFD) of parametric faults is considered in connection with closed loop feedback systems. AFD involves auxiliary signals applied on the closed loop system. A fault signature matrix is introduced in connection with AFD and it is shown that if a limited number of faults can...

  14. Enhanced treatment of refinery soils with open-system slurry reactors

    International Nuclear Information System (INIS)

    Blackburn, J.W.; Lee, M.K.; Horn, W.C.

    1995-01-01

    Refinery site cleanups of residual hydrocarbons arising from long-term operations have become a concern. Because contaminated soil has been generated over many years from spills of many types of materials, it is often difficult to identify the actual spilled material. Because many of these materials are weathered, the less degradable fractions can predominate, creating a challenge for bioremedial process solutions. Open-system slurry reactors were run with an aged refinery soil after a 6-month period of field bioremediation in which 23% TPH removal resulted. The open system (a system where the liquid medium was replaced daily and the solids were retained in the reactor for 2 weeks) achieved 60 to 80% total petroleum hydrocarbon (TPH) removal based on the initial, prefield bioremediation soil concentration. A process concept twice as effective as other bioremediation schemes has been devised that takes advantage of the formation and removal of small black particulate solids in an open or continuous slurry reactor configuration. These small black particles are chemically or biologically produced in the open system and with their small size and low density are easily elutriated from the bioreactor as the liquid medium is changed. A statistically designed experiment has determined optimal values of nutrients, temperature, and mixing

  15. A review of the distribution coefficients of trace elements in soils: influence of sorption system, element characteristics, and soil colloidal properties.

    Science.gov (United States)

    Shaheen, Sabry M; Tsadilas, Christos D; Rinklebe, Jörg

    2013-12-01

    Knowledge about the behavior and reactions of separate soil components with trace elements (TEs) and their distribution coefficients (Kds) in soils is a key issue in assessing the mobility and retention of TEs. Thus, the fate of TEs and the toxic risk they pose depend crucially on their Kd in soil. This article reviews the Kd of TEs in soils as affected by the sorption system, element characteristics, and soil colloidal properties. The sorption mechanism, determining factors, favorable conditions, and competitive ions on the sorption and Kd of TEs are also discussed here. This review demonstrates that the Kd value of TEs does not only depend on inorganic and organic soil constituents, but also on the nature and characteristics of the elements involved as well as on their competition for sorption sites. The Kd value of TEs is mainly affected by individual or competitive sorption systems. Generally, the sorption in competitive systems is lower than in mono-metal sorption systems. More strongly sorbed elements, such as Pb and Cu, are less affected by competition than mobile elements, such as Cd, Ni, and Zn. The sorption preference exhibited by soils for elements over others may be due to: (i) the hydrolysis constant, (ii) the atomic weight, (iii) the ionic radius, and subsequently the hydrated radius, and (iv) its Misono softness value. Moreover, element concentrations in the test solution mainly affect the Kd values. Mostly, values of Kd decrease as the concentration of the included cation increases in the test solution. Additionally, the Kd of TEs is controlled by the sorption characteristics of soils, such as pH, clay minerals, soil organic matter, Fe and Mn oxides, and calcium carbonate. However, more research is required to verify the practical utilization of studying Kd of TEs in soils as a reliable indicator for assessing the remediation process of toxic metals in soils and waters. © 2013 Elsevier B.V. All rights reserved.

  16. A systemic approach for modeling soil functions

    Science.gov (United States)

    Vogel, Hans-Jörg; Bartke, Stephan; Daedlow, Katrin; Helming, Katharina; Kögel-Knabner, Ingrid; Lang, Birgit; Rabot, Eva; Russell, David; Stößel, Bastian; Weller, Ulrich; Wiesmeier, Martin; Wollschläger, Ute

    2018-03-01

    The central importance of soil for the functioning of terrestrial systems is increasingly recognized. Critically relevant for water quality, climate control, nutrient cycling and biodiversity, soil provides more functions than just the basis for agricultural production. Nowadays, soil is increasingly under pressure as a limited resource for the production of food, energy and raw materials. This has led to an increasing demand for concepts assessing soil functions so that they can be adequately considered in decision-making aimed at sustainable soil management. The various soil science disciplines have progressively developed highly sophisticated methods to explore the multitude of physical, chemical and biological processes in soil. It is not obvious, however, how the steadily improving insight into soil processes may contribute to the evaluation of soil functions. Here, we present to a new systemic modeling framework that allows for a consistent coupling between reductionist yet observable indicators for soil functions with detailed process understanding. It is based on the mechanistic relationships between soil functional attributes, each explained by a network of interacting processes as derived from scientific evidence. The non-linear character of these interactions produces stability and resilience of soil with respect to functional characteristics. We anticipate that this new conceptional framework will integrate the various soil science disciplines and help identify important future research questions at the interface between disciplines. It allows the overwhelming complexity of soil systems to be adequately coped with and paves the way for steadily improving our capability to assess soil functions based on scientific understanding.

  17. Soil microbial effects of smelter induced heavy metal contamination

    Energy Technology Data Exchange (ETDEWEB)

    Nordgren, A

    1986-01-01

    The soil concentrations of Cu and Zn at the secondary smelter were 20 00 mu g/g dry soil. Close to the primary smelter the soil was contaminated with more than ten elements including Pb, Zn, Cu and As at levels ranging between 6000 and 1000 mu g/g dry soil. The correlations between the concentrations of the metals were high at both smelters. Soil respiration rate decreased by about 75% close to both smelters. Total and fluorescein diacetate stained mycelial lengths decrease with increasing heavy metal pollution at the secondary but not at the primary smelter. The fungal community structure was strongly affected by the contamination. General common in coniferous forest soils such as Penicillium and Oidiodendron virtually vanished, while less frequent species like Paecilomyces farinosus and Geomyces pannorum dominated the site close to the smelter. Colony forming units of a number of functional groups of bacteria were found to be very sensitive to metal contamination. The urease activity of the soil was inhibited. Multivariate statistical analyses showed that the metal contamination was the major environmental influence on the microbiotain the soils studied. A study of about 200 decomposition curves resulting from glutamic acid additions to the different soils produced four microbially related parameters: basal respiration rate, initial respiration rate after the addition of the glutamic acid, specific respiration rate during the exponential increase of the respiration rate and the lag time before the exponential phase. With 53 refs.

  18. Soil phosphorus dynamics in a humid tropical silvopastoral system

    Energy Technology Data Exchange (ETDEWEB)

    Cooperband, L.R.

    1992-01-01

    In developing countries of the humid tropics, timber exploitation and agricultural expansion frequently result in deforestation. Extensive land management, coupled with inherently low soil fertility invariably produce declines in agricultural/livestock productivity which eventually lead to land abandonment and further deforestation. Phosphorus is often the major nutrient limiting plant growth in tropical soils. Agroforestry systems have been considered as viable alternatives to current land use practices. Several hypotheses suggest that combining trees with crops or pasture, especially leguminous species will improve soil nutrient cycling, soil structure and soil organic matter. In this experiment Erythrina berteroana (an arboreous legume) was grown in native grass pastures in Costa Rica to determine the effects of tree pruning and cattle grazing on soil P availability. I measured soil P fluxes as well as changes in pasture biomass over an 18-month period. In a separate field experiment, I determined decomposition rates and P release characteristics of Erythrina leaves, pasture grass clippings and cattle dung. Erythrina leaves decomposed faster than both pasture grass and cattle dung. Erythrina and pasture residues released 4-5 times less P than dung. Phosphorus fluxes after tree pruning and grazing were highly dynamic for all treatments. Tree pruning increased labile soil P over time when coupled with grazing. Pasture biomass production was greatest in the grazed tree treatment. Pasture biomass P production and concentration was greatest in the non-grazed treatment. Trees and grazing together tended to increase nutrient (P) turnover which stimulated biomass production. In contrast, trees without grazing promoted nutrient (P) accumulation in pasture biomass.

  19. Soil phosphorus dynamics in a humid tropical silvopastoral system

    International Nuclear Information System (INIS)

    Cooperband, L.R.

    1992-01-01

    In developing countries of the humid tropics, timber exploitation and agricultural expansion frequently result in deforestation. Extensive land management, coupled with inherently low soil fertility invariably produce declines in agricultural/livestock productivity which eventually lead to land abandonment and further deforestation. Phosphorus is often the major nutrient limiting plant growth in tropical soils. Agroforestry systems have been considered as viable alternatives to current land use practices. Several hypotheses suggest that combining trees with crops or pasture, especially leguminous species will improve soil nutrient cycling, soil structure and soil organic matter. In this experiment Erythrina berteroana (an arboreous legume) was grown in native grass pastures in Costa Rica to determine the effects of tree pruning and cattle grazing on soil P availability. I measured soil P fluxes as well as changes in pasture biomass over an 18-month period. In a separate field experiment, I determined decomposition rates and P release characteristics of Erythrina leaves, pasture grass clippings and cattle dung. Erythrina leaves decomposed faster than both pasture grass and cattle dung. Erythrina and pasture residues released 4-5 times less P than dung. Phosphorus fluxes after tree pruning and grazing were highly dynamic for all treatments. Tree pruning increased labile soil P over time when coupled with grazing. Pasture biomass production was greatest in the grazed tree treatment. Pasture biomass P production and concentration was greatest in the non-grazed treatment. Trees and grazing together tended to increase nutrient (P) turnover which stimulated biomass production. In contrast, trees without grazing promoted nutrient (P) accumulation in pasture biomass

  20. Soil and crop management experiments in the Laboratory Biosphere: An analogue system for the Mars on Earth ® facility

    Science.gov (United States)

    Silverstone, S.; Nelson, M.; Alling, A.; Allen, J. P.

    During the years 2002 and 2003, three closed system experiments were carried out in the "Laboratory Biosphere" facility located in Santa Fe, New Mexico. The program involved experimentation of "Hoyt" Soy Beans, (experiment #1) USU Apogee Wheat (experiment #2) and TU-82-155 sweet potato (experiment #3) using a 5.37 m 2 soil planting bed which was 30 cm deep. The soil texture, 40% clay, 31% sand and 28% silt (a clay loam), was collected from an organic farm in New Mexico to avoid chemical residues. Soil management practices involved minimal tillage, mulching, returning crop residues to the soil after each experiment and increasing soil biota by introducing worms, soil bacteria and mycorrhizae fungi. High soil pH of the original soil appeared to be a factor affecting the first two experiments. Hence, between experiments #2 and #3, the top 15 cm of the soil was amended using a mix of peat moss, green sand, humates and pumice to improve soil texture, lower soil pH and increase nutrient availability. This resulted in lowering the initial pH of 8.0-6.7 at the start of experiment #3. At the end of the experiment, the pH was 7.6. Soil nitrogen and phosphorus has been adequate, but some chlorosis was evident in the first two experiments. Aphid infestation was the only crop pest problem during the three experiments and was handled using an introduction of Hyppodamia convergens. Experimentation showed there were environmental differences even in this 1200 cubic foot ecological system facility, such as temperature and humidity gradients because of ventilation and airflow patterns which resulted in consequent variations in plant growth and yield. Additional humidifiers were added to counteract low humidity and helped optimize conditions for the sweet potato experiment. The experience and information gained from these experiments are being applied to the future design of the Mars On Earth ® facility (Silverstone et al., Development and research program for a soil

  1. Soil-atmosphere greenhouse-gas exchange in a bioretention system

    Science.gov (United States)

    Daly, E.; Chan, H.; Beringer, J.; Livesley, S. J.

    2011-12-01

    Bioretention systems are a popular green-technology for the management of urban stormwater runoff in many countries. They typically consist of a trench filled with a highly permeable soil medium that supports vegetation; runoff is diverted to bioretention systems and, by percolating through the filter medium, is subjected to a number of treatment processes. Nitrogen (N) is one of the key pollutants targeted by bioretention systems, which are able to reduce N concentrations considerably from inflow to outflow. To increase N removal, a saturated zone at the bottom of the filter medium is often artificially generated, to both enhance the denitrification process and increase the water available to the vegetation between inflow events. Although studies on the N-removal performance of bioretention systems are widely available in the literature, less is known about the exchange of greenhouse gases (GHG), especially nitrous oxide (N2O), between the bioretention systems and the atmosphere. Here, we present an experimental pilot study to measure N2O and CO2 soil emissions in a bioretention system installed on the Clayton Campus of Monash University in Melbourne, Australia. The bioretention system is divided into three cells, each 15 m2; the system as a whole receives water run-off from 4500 m2 of impervious car park. We monitored two cells with mostly sandy-loam vegetated with native sedges (mainly Carex Appressa and Lomandra Longifolia), one with and one without a saturated zone. Three manual flux chambers were installed in both cells. Gas flux samples were taken twice a week at about 11 am between the 2nd of March and the 18th of May 2011 (late summer and fall). Since October 2010, air-phase soil CO2 concentration profiles were measured continuously using solid-state infrared CO2 transmitters (GMT-221 model, Vaisala, Finland), along with soil moisture and soil temperature. Preliminary analysis of the chamber data (March only) showed that N2O fluxes were in general below 50

  2. Closed Brayton cycle power conversion systems for nuclear reactors :

    Energy Technology Data Exchange (ETDEWEB)

    Wright, Steven A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lipinski, Ronald J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Vernon, Milton E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sanchez, Travis [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2006-04-01

    the manufacturers site (Barber-Nichols Inc.) and installed and operated at Sandia. A sufficiently detailed description of the loop is provided in this report along with the design characteristics of the turbo-alternator-compressor set to allow other researchers to compare their results with those measured in the Sandia test-loop. The third task consisted of a validation effort. In this task the test loop was operated and compared with the modeled results to develop a more complete understanding of this electrically heated closed power generation system and to validate the model. The measured and predicted system temperatures and pressures are in good agreement, indicating that the model is a reasonable representation of the test loop. Typical deviations between the model and the hardware results are less than 10%. Additional tests were performed to assess the capability of the Brayton engine to continue to remove decay heat after the reactor/heater is shutdown, to develop safe and effective control strategies, and to access the effectiveness of gas inventory control as an alternative means to provide load following. In one test the heater power was turned off to simulate a rapid reactor shutdown, and the turbomachinery was driven solely by the sensible heat stored in the heater for over 71 minutes without external power input. This is an important safety feature for CBC systems as it means that the closed Brayton loop will keep cooling the reactor without the need for auxiliary power (other than that needed to circulate the waste heat rejection coolant) provided the heat sink is available.

  3. Soil Temperature and Moisture Profile (STAMP) System Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Cook, David R. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-11-01

    The soil temperature and moisture profile system (STAMP) provides vertical profiles of soil temperature, soil water content (soil-type specific and loam type), plant water availability, soil conductivity, and real dielectric permittivity as a function of depth below the ground surface at half-hourly intervals, and precipitation at one-minute intervals. The profiles are measured directly by in situ probes at all extended facilities of the SGP climate research site. The profiles are derived from measurements of soil energy conductivity. Atmospheric scientists use the data in climate models to determine boundary conditions and to estimate the surface energy flux. The data are also useful to hydrologists, soil scientists, and agricultural scientists for determining the state of the soil. The STAMP system replaced the SWATS system in early 2016.

  4. Cyanobacteria to Link Closed Ecological Systems and In-Situ Resources Utilization Processes

    Science.gov (United States)

    Brown, Igor

    production), require significant power (tens of kWh/kg), and in many processes requires high temperatures ( 1000o C) to be effec-tive; therefore they are not compatible with closed life support systems such as MELiSSA. With the release of the NASA Lunar Architecture Team's latest Lunar Mission Strategy, the investigation of more efficient air bioregeneration techniques based on the metabolism of lower order photosynthetic organisms with ability to leach (weather) in situ rocks appears to be very timely and relevant. Cyanobacteria (CB) are known as very effective producers of O2, proteins, vitamins, immunomodulators (Brown et al., 2006) and as mineral destroyers (Friedmann, 1980; Gorbushina and Palinska, 1999) to supply themselves with different elements. Results: As a result of pilot studies, we propose, therefore, to develop a concept for semi-closed integrated system that uses CB to extract useful elements for their sustaining, to revitalize air and produce valuable biomolecules. Such a system could be the foundation of a self-sustaining extraterrestrial outpost (Hendrickx, De Wever et al., 2005; Handford, 2006). A potential advantage of a cyanobacterial photoreactor placed between LSS and ISRU loops is the possibility of supplying these systems with extracted elements and compounds from the regolith. In addition, waste regolith may be transformed into additional products such as methane, biomass, and organic and inorganic soil enrichment for the cultivation of high plants. We have used several species of siderophilic CB isolated from iron-depositing hot springs in Yellowstone Na-tional Park (Brown et al., 2007) to characterize their ability to utilize terrestrial analogs of lunar and martian rocks. Severe dilution of a rich medium for the cultivation of CB with deionized water did not lead to the growth repression of the cyanobacterium JSC-12. It was found that the suspension of JSC Mars-1 soil stimulant in deionized water sup-ports the proliferation of several

  5. Combined effects of DOM extracted from site soil/compost and biosurfactant on the sorption and desorption of PAHs in a soil-water system

    Energy Technology Data Exchange (ETDEWEB)

    Yu Hui, E-mail: yuhui200@uregina.ca [Environmental Systems Engineering Program, Faculty of Engineering and Applied Science, University of Regina, Regina, SK S4S 0A2 (Canada); Huang Guohe, E-mail: gordon.huang@uregina.ca [Environmental Systems Engineering Program, Faculty of Engineering and Applied Science, University of Regina, Regina, SK S4S 0A2 (Canada); An Chunjiang, E-mail: an209@uregina.ca [Environmental Systems Engineering Program, Faculty of Engineering and Applied Science, University of Regina, Regina, SK S4S 0A2 (Canada); Wei Jia, E-mail: jia.wei@iseis.org [Environmental Systems Engineering Program, Faculty of Engineering and Applied Science, University of Regina, Regina, SK S4S 0A2 (Canada)

    2011-06-15

    Highlights: {yields} The combined DOM and biosurfactant significantly enhanced desorption of PAHs. {yields} Compost DOM exhibited higher desorption enhancement capacity than the soil DOM. {yields} Competition among PAHs, DOM and biosurfactant for sorption site determined desorption of PAHs from soil. {yields} Formation of DOM-biosurfactant complex enhance desorption extent of PAHs. - Abstract: The combined effects of DOM and biosurfactant on the sorption/desorption behavior of phenanthrene (PHE) and pyrene (PYR) in soil water systems were systematically investigated. Two origins of DOMs (extracted from soil and extracted from food waste compost) and an anionic biosurfactant (rhamnolipid) were introduced. The presence of DOM in the aqueous phase could decrease the sorption of PAHs, thus influence their mobility. Desorption enhancement for both PHE and PYR in the system with compost DOM was greater than that in the soil DOM system. This is due to the differences in specific molecular structures and functional groups of two DOMs. With the co-existence of biosurfactant and DOM, partitioning is the predominant process and the desorption extent was much higher than the system with DOM or biosurfactant individually. For PHE, the desorption enhancement of combined DOM and biosurfactant was larger than the sum of DOM or biosurfactant; however desorption enhancement for PYR in the combined system was less than the additive enhancement in two individual system under low PAH concentration. This could be explained as the competition sorption among PAHs, DOM and biosurfactant. The results of this study will help to clarify the transport of petroleum pollutants in the remediation of HOCs-contaminated soils.

  6. Combined effects of DOM extracted from site soil/compost and biosurfactant on the sorption and desorption of PAHs in a soil-water system

    International Nuclear Information System (INIS)

    Yu Hui; Huang Guohe; An Chunjiang; Wei Jia

    2011-01-01

    Highlights: → The combined DOM and biosurfactant significantly enhanced desorption of PAHs. → Compost DOM exhibited higher desorption enhancement capacity than the soil DOM. → Competition among PAHs, DOM and biosurfactant for sorption site determined desorption of PAHs from soil. → Formation of DOM-biosurfactant complex enhance desorption extent of PAHs. - Abstract: The combined effects of DOM and biosurfactant on the sorption/desorption behavior of phenanthrene (PHE) and pyrene (PYR) in soil water systems were systematically investigated. Two origins of DOMs (extracted from soil and extracted from food waste compost) and an anionic biosurfactant (rhamnolipid) were introduced. The presence of DOM in the aqueous phase could decrease the sorption of PAHs, thus influence their mobility. Desorption enhancement for both PHE and PYR in the system with compost DOM was greater than that in the soil DOM system. This is due to the differences in specific molecular structures and functional groups of two DOMs. With the co-existence of biosurfactant and DOM, partitioning is the predominant process and the desorption extent was much higher than the system with DOM or biosurfactant individually. For PHE, the desorption enhancement of combined DOM and biosurfactant was larger than the sum of DOM or biosurfactant; however desorption enhancement for PYR in the combined system was less than the additive enhancement in two individual system under low PAH concentration. This could be explained as the competition sorption among PAHs, DOM and biosurfactant. The results of this study will help to clarify the transport of petroleum pollutants in the remediation of HOCs-contaminated soils.

  7. Modelling water fluxes in a pine wood soil-vegetation-atmosphere system. Comparison of a water budget and water flow model using different parameter data sources

    International Nuclear Information System (INIS)

    Schneider, S.; Jacques, D.; Mallants, D.

    2010-01-01

    For modelling complex hydrological problems, realistic models and accurate hydraulic properties are needed. A mechanistic model (HYDRUS-1D) and a compartment model are evaluated for simulating the water balance in a soil-vegetation-atmosphere system using time series of measured water content at several depths in two lysimeters in a podzol soil with Scots Pine vegetation. 10 calibration scenarios are used to investigate the impact of the model type and the number of horizons in the profile on the calibration accuracy. Main results are: (i) with a large number of soil layers, both models describe accurately the water contents at all depths, (II) the number of soil layers is the major factor that controls the quality of the calibration. The compartment model is as an abstracted model and the mechanistic model is our reference model. Drainage values are the considered output. Drainage values simulated by the abstracted model were close to those of the reference model when averaged over a sufficiently long period (about 9 months). This result suggests that drainage values obtained with an abstracted model are reliably when averaged over sufficiently long periods; the abstracted model needs less computational time without an important loss of accuracy.

  8. Modelling water fluxes in a pine wood soil-vegetation-atmosphere system. Comparison of a water budget and water flow model using different parameter data sources

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, S.; Jacques, D.; Mallants, D.

    2010-02-15

    For modelling complex hydrological problems, realistic models and accurate hydraulic properties are needed. A mechanistic model (HYDRUS-1D) and a compartment model are evaluated for simulating the water balance in a soil-vegetation-atmosphere system using time series of measured water content at several depths in two lysimeters in a podzol soil with Scots Pine vegetation. 10 calibration scenarios are used to investigate the impact of the model type and the number of horizons in the profile on the calibration accuracy. Main results are: (i) with a large number of soil layers, both models describe accurately the water contents at all depths, (II) the number of soil layers is the major factor that controls the quality of the calibration. The compartment model is as an abstracted model and the mechanistic model is our reference model. Drainage values are the considered output. Drainage values simulated by the abstracted model were close to those of the reference model when averaged over a sufficiently long period (about 9 months). This result suggests that drainage values obtained with an abstracted model are reliably when averaged over sufficiently long periods; the abstracted model needs less computational time without an important loss of accuracy.

  9. From Process Understanding Via Soil Functions to Sustainable Soil Management - A Systemic Approach

    Science.gov (United States)

    Wollschlaeger, U.; Bartke, S.; Bartkowski, B.; Daedlow, K.; Helming, K.; Kogel-Knabner, I.; Lang, B.; Rabot, E.; Russell, D.; Stößel, B.; Weller, U.; Wiesmeier, M.; Rabot, E.; Vogel, H. J.

    2017-12-01

    Fertile soils are central resources for the production of biomass and the provision of food and energy. A growing world population and latest climate targets lead to an increasing demand for both, food and bio-energy, which requires preserving and improving the long-term productivity of soils as a bio-economic resource. At the same time, other soil functions and ecosystem services need to be maintained: filter for clean water, carbon sequestration, provision and recycling of nutrients, and habitat for biological activity. All these soil functions result from the interaction of a multitude of physical, chemical and biological processes that are not yet sufficiently understood. In addition, we lack understanding about the interplay between the socio-economic system and the soil system and how soil functions benefit human wellbeing. Hence, a solid and integrated assessment of soil quality requires the consideration of the ensemble of soil functions and its relation to soil management to finally be able to develop site-specific options for sustainable soil management. We present an integrated modeling approach that investigates the influence of soil management on the ensemble of soil functions. It is based on the mechanistic relationships between soil functional attributes, each explained by a network of interacting processes as derived from scientific evidence. As the evidence base required for feeding the model is for the most part stored in the existing scientific literature, another central component of our work is to set up a public "knowledge-portal" providing the infrastructure for a community effort towards a comprehensive knowledge base on soil processes as a basis for model developments. The connection to the socio-economic system is established using the Drivers-Pressures-Impacts-States-Responses (DPSIR) framework where our improved understanding about soil ecosystem processes is linked to ecosystem services and resource efficiency via the soil functions.

  10. Soil 13C–15N dynamics in an N2-fixing clover system under long-term exposure to elevated atmospheric CO2

    NARCIS (Netherlands)

    Groenigen, van C.J.; Six, J.; Harris, D.; Blum, H.; Kessel, van C.

    2003-01-01

    Reduced soil N availability under elevated CO2 may limit the plant's capacity to increase photosynthesis and thus the potential for increased soil C input. Plant productivity and soil C input should be less constrained by available soil N in an N2-fixing system. We studied the effects of Trifolium

  11. Plant-uptake of uranium: Hydroponic and soil system studies

    Science.gov (United States)

    Ramaswami, A.; Carr, P.; Burkhardt, M.

    2001-01-01

    Limited information is available on screening and selection of terrestrial plants for uptake and translocation of uranium from soil. This article evaluates the removal of uranium from water and soil by selected plants, comparing plant performance in hydroponic systems with that in two soil systems (a sandy-loam soil and an organic-rich soil). Plants selected for this study were Sunflower (Helianthus giganteus), Spring Vetch (Vicia sativa), Hairy Vetch (Vicia villosa), Juniper (Juniperus monosperma), Indian Mustard (Brassica juncea), and Bush Bean (Phaseolus nanus). Plant performance was evaluated both in terms of the percent uranium extracted from the three systems, as well as the biological absorption coefficient (BAC) that normalized uranium uptake to plant biomass. Study results indicate that uranium extraction efficiency decreased sharply across hydroponic, sandy and organic soil systems, indicating that soil organic matter sequestered uranium, rendering it largely unavailable for plant uptake. These results indicate that site-specific soils must be used to screen plants for uranium extraction capability; plant behavior in hydroponic systems does not correlate well with that in soil systems. One plant species, Juniper, exhibited consistent uranium extraction efficiencies and BACs in both sandy and organic soils, suggesting unique uranium extraction capabilities.

  12. Improvement of Soil Biology Characteristics at Paddy Field by System of Rice Intensification

    Directory of Open Access Journals (Sweden)

    Widyatmani Sih Dewi

    2015-07-01

    Full Text Available The aim of the research was to test the System of Rice Intensification (SRI method in improving the biological properties of paddy soil. The indicators of improvement were measured by the number of earthworm feces (cast, and the population of some microbial and nutrient content in the cast. The experiments were performed by comparing the three methods, namely: (1 SRI, (2 semi-conventional, and (3 conventional, using Randomized Completely Block Design. Each treatment was repeated nine times. The experiments were performed in the paddy fields belonging to farmers in Sukoharjo, Central Java. The result showed that the SRI (application of 1 tons ha-1 of vermicompost + 50% of inorganic fertilizer dosage tends to increase the number of earthworms cast. It is an indicator of earthworm activity in soil. Earthworms cast contains more phosphate solubilizing bacteria (12.98 x 1010cfu and N content (1.23% compared to its surrounding soil. There is a close functional relation between earthworms cast with total tiller number. SRI method is better than the other two methods to improve the biological characteristics of paddy soil that has the potential to maintain the sustainability of soil productivity.

  13. Nuclear reactor closed Brayton cycle power conversion system optimization trends for extra-terrestrial applications

    International Nuclear Information System (INIS)

    Ashe, T.L.; Baggenstoss, W.G.; Bons, R.

    1990-01-01

    Extra-terrestrial exploration and development missions of the next century will require reliable, low-mass power generation modules of 100 kW e and more. These modules will be required to support both fixed-base and manned rover/explorer power needs. Low insolation levels at and beyond Mars and long periods of darkness on the moon make solar conversion less desirable for surface missions. For these missions, a closed Brayton cycle energy conversion system coupled with a reactor heat source is a very attractive approach. The authors conducted parametric studies to assess optimized system design trends for nuclear-Brayton systems as a function of operating environment and user requirements. The inherent design flexibility of the closed Brayton cycle energy conversion system permits ready adaptation of the system to future design constraints. This paper describes a dramatic contrast between system designs requiring man-rated shielding. The paper also considers the ramification of using indigenous materials to provide reactor shielding for a fixed-base power source

  14. Soil Microbial Activity in Conventional and Organic Agricultural Systems

    Directory of Open Access Journals (Sweden)

    Romero F.V. Carneiro

    2009-06-01

    Full Text Available The aim of this study was to evaluate microbial activity in soils under conventional and organic agricultural system management regimes. Soil samples were collected from plots under conventional management (CNV, organic management (ORG and native vegetation (AVN. Soil microbial activity and biomass was significantly greater in ORG compared with CNV. Soil bulk density decreased three years after adoption of organic system. Soil organic carbon (SOC was higher in the ORG than in the CNV. The soil under organic agricultural system presents higher microbial activity and biomass and lower bulk density than the conventional agricultural system.

  15. Soil surface CO2 fluxes on the Konza Prairie

    Science.gov (United States)

    Norman, J. M.; Garcia, R.; Verma, Shoshi B.

    1990-01-01

    The utilization of a soil chamber to measure fluxes of soil-surface CO2 fluxes is described in terms of equipment, analytical methods, and estimate quality. A soil chamber attached to a gas-exchange system measures the fluxes every 5-15 min, and the data are compared to measurements of the CO2 fluxes from the canopy and from the soil + canopy. The soil chamber yields good measurements when operated in a closed system that is ported to the free atmosphere, and the CO2 flux is found to have a diurnal component.

  16. Genetic transformation of Bacillus strains close to bacillus subtilis and isolated from the soil

    International Nuclear Information System (INIS)

    Van, C.K.; Kuzin, Yu.Yu.; Kozlovskii, Yu.E.; Prozorov, A.A.

    1986-01-01

    Chromosomal and plasmid transformation was found in five out of 118 Bacillus strains, close or identical to Bacillus subtilis, and isolated from soil in Moscow or in the Moscow district. The efficiency of transformation in these strains was lower than that in derivatives of Bac. subtilis strain 168. In these strains the ability to undergo transformation was dependent on the rate of sporulation and the presence of restrictases. As in the case of Bac. subtilis 168 the strains isolated may be used as models in genetic transformation studies on Bac. subtilis

  17. Induction of systemic resistance in plants by biochar, a soil-applied carbon sequestering agent.

    Science.gov (United States)

    Elad, Yigal; David, Dalia Rav; Harel, Yael Meller; Borenshtein, Menahem; Kalifa, Hananel Ben; Silber, Avner; Graber, Ellen R

    2010-09-01

    Biochar is the solid coproduct of biomass pyrolysis, a technique used for carbon-negative production of second-generation biofuels. The biochar can be applied as a soil amendment, where it permanently sequesters carbon from the atmosphere as well as improves soil tilth, nutrient retention, and crop productivity. In addition to its other benefits in soil, we found that soil-applied biochar induces systemic resistance to the foliar fungal pathogens Botrytis cinerea (gray mold) and Leveillula taurica (powdery mildew) on pepper and tomato and to the broad mite pest (Polyphagotarsonemus latus Banks) on pepper. Levels of 1 to 5% biochar in a soil and a coconut fiber-tuff potting medium were found to be significantly effective at suppressing both diseases in leaves of different ages. In long-term tests (105 days), pepper powdery mildew was significantly less severe in the biochar-treated plants than in the plants from the unamended controls although, during the final 25 days, the rate of disease development in the treatments and controls was similar. Possible biochar-related elicitors of systemic induced resistance are discussed.

  18. Soil chemistry and pollution study of a closed landfill site at Ampar Tenang, Selangor, Malaysia.

    Science.gov (United States)

    Mohd Adnan, Siti Nur Syahirah Binti; Yusoff, Sumiani; Piaw, Chua Yan

    2013-06-01

    A total of 20 landfills are located in State of Selangor, Malaysia. This includes the Ampar Tenang landfill site, which was closed on 26 January 2010. It was reported that the landfill has been upgraded to a level I type of sanitary classification. However, the dumpsite area is not being covered according to the classification. In addition, municipal solid waste was dumped directly on top of the unlined natural alluvium formation. This does not only contaminate surface and subsurface soils, but also initiates the potential risk of groundwater pollution. Based on previous studies, the Ampar Tenang soil has been proven to no longer be capable of preventing pollution migration. In this study, metal concentrations of soil samples up to 30 m depth were analyzed based on statistical analysis. It is very significant because research of this type has not been carried out before. The subsurface soils were significantly polluted by arsenic (As), lead (Pb), iron (Fe), copper (Cu) and aluminium (Al). As and Pb exceeded the safe limit values of 5.90 mg/kg and 31.00 mg/kg, respectively, based on Provincial Sediment Quality Guidelines for Metals and the Interim Sediment Quality Values. Furthermore, only Cu concentrations showed a significantly decreasing trend with increasing depth. Most metals were found on clay-type soils based on the cluster analysis method. Moreover, the analysis also differentiates two clusters: cluster I-Pb, As, zinc, Cu, manganese, calcium, sodium, magnesium, potassium and Fe; cluster II-Al. Different clustering may suggest a different contamination source of metals.

  19. Cropping system impact on soil quality determinants

    Directory of Open Access Journals (Sweden)

    M. VESTBERG

    2008-12-01

    Full Text Available Worldwide interest in soil quality evaluation has increased rapidly throughout the past decade, prompting us to evaluate the long-term impact of four cropping systems on several biological, chemical and physical determinants of soil quality. We hypothesized that after 17 years several of the determinants would show significant differences between conventional cereal and low input/organic rotations. Four crop rotations were imposed on a silt soil from 1982 through 1999. Rotation A was a conventionally managed cereal rotation that received 100% of the recommended mineral fertilizer each year. Rotation B was also managed conventionally from 1982 until 1993, although it received only 50% of the recommended mineral fertilizer. From 1994 through 1999, rotation B was managed as an organic rotation. Rotations C and D were low-input rotations with plant residues returned either untreated (Cor composted (Dfrom 1982 until 1994.From 1994 through 1999,they were also anaged organically. Significant decreases in extractable phosphorus (Pand potassium were observed in rotations C and D compared with rotation A, presumably because their yearly nutrient inputs were somewhat lower. The amount of soil organic carbon (Corg, soil water holding capacity, the numbers and biomass of earthworms and the microbial biomass carbon and nitrogen were or tended to be higher in low input/organic than in conventionally managed plots. These effects may be in connection with the slightly increased levels of Corg in soil of the organic rotations. Activities of twelve enzymes were strongly affected by sampling time (early-versus late-summer, but much less by long-term management. Litter decomposition, numbers of soil nematodes, arbuscular mycorrhizal (AMfungal diversity,AM spore density and AM functioning were little affected by rotation. However,AM spore density correlated positively with the high amounts of extractable calcium and P which were a result from excessive liming applied

  20. Identifying the closeness of eigenstates in quantum many-body systems

    International Nuclear Information System (INIS)

    Li Hai-bin; Yang Yang; Wang Pei; Wang Xiao-guang

    2017-01-01

    We propose a quantity called modulus fidelity to measure the closeness of two quantum pure states. We use it to investigate the closeness of eigenstates in one-dimensional hard-core bosons. When the system is integrable, eigenstates close to their neighbor or not, which leads to a large fluctuation in the distribution of modulus fidelity. When the system becomes chaos, the fluctuation is reduced dramatically, which indicates all eigenstates become close to each other. It is also found that two kind of closeness, i.e., closeness of eigenstates and closeness of eigenvalues, are not correlated at integrability but correlated at chaos. We also propose that the closeness of eigenstates is the underlying mechanism of eigenstate thermalization hypothesis (ETH) which explains the thermalization in quantum many-body systems. (paper)

  1. Closing the gasoline system

    International Nuclear Information System (INIS)

    Hutcheson, R.C.

    1992-01-01

    In this paper, a representative of the Oil Companies' European Organization for Environmental and Health Protection (CONCAWE), argues the advantages of closing the gasoline system. Because this decouples the product from the environment, health risks and environmental damage are reduced. It is also more effective than changing the composition of gasoline because it offers better cost effectiveness, energy efficiency and the minimization of carbon dioxide release into the environment. However it will take time and political will to change until all European vehicles are fitted with three way catalysts and carbon canisters: control systems to monitor such systems will also need to be set up. However CONCAWE still recommends its adoption. (UK)

  2. Closed hierarchy of correlations in Markovian open quantum systems

    International Nuclear Information System (INIS)

    Žunkovič, Bojan

    2014-01-01

    We study the Lindblad master equation in the space of operators and provide simple criteria for closeness of the hierarchy of equations for correlations. We separately consider the time evolution of closed and open systems and show that open systems satisfying the closeness conditions are not necessarily of Gaussian type. In addition, we show that dissipation can induce the closeness of the hierarchy of correlations in interacting quantum systems. As an example we study an interacting optomechanical model, the Fermi–Hubbard model, and the Rabi model, all coupled to a fine-tuned Markovian environment and obtain exact analytic expressions for the time evolution of two-point correlations. (paper)

  3. Enhanced Soil Moisture Initialization Using Blended Soil Moisture Product and Regional Optimization of LSM-RTM Coupled Land Data Assimilation System.

    Science.gov (United States)

    Nair, A. S.; Indu, J.

    2017-12-01

    Prediction of soil moisture dynamics is high priority research challenge because of the complex land-atmosphere interaction processes. Soil moisture (SM) plays a decisive role in governing water and energy balance of the terrestrial system. An accurate SM estimate is imperative for hydrological and weather prediction models. Though SM estimates are available from microwave remote sensing and land surface model (LSM) simulations, it is affected by uncertainties from several sources during estimation. Past studies have generally focused on land data assimilation (DA) for improving LSM predictions by assimilating soil moisture from single satellite sensor. This approach is limited by the large time gap between two consequent soil moisture observations due to satellite repeat cycle of more than three days at the equator. To overcome this, in the present study, we have performed DA using ensemble products from the soil moisture operational product system (SMOPS) blended soil moisture retrievals from different satellite sensors into Noah LSM. Before the assimilation period, the Noah LSM is initialized by cycling through seven multiple loops from 2008 to 2010 forcing with Global data assimilation system (GDAS) data over the Indian subcontinent. We assimilated SMOPS into Noah LSM for a period of two years from 2010 to 2011 using Ensemble Kalman Filter within NASA's land information system (LIS) framework. Results show that DA has improved Noah LSM prediction with a high correlation of 0.96 and low root mean square difference of 0.0303 m3/m3 (figure 1a). Further, this study has also investigated the notion of assimilating microwave brightness temperature (Tb) as a proxy for SM estimates owing to the close proximity of Tb and SM. Preliminary sensitivity analysis show a strong need for regional parameterization of radiative transfer models (RTMs) to improve Tb simulation. Towards this goal, we have optimized the forward RTM using swarm optimization technique for direct Tb

  4. Closing open SDL-systems for model checking with DTSpin

    NARCIS (Netherlands)

    N. Ioustinova (Natalia); N. Sidorova; M. Steffen

    2002-01-01

    textabstractModel checkers like Spin can handle closed reactive systems, only. Thus to handle open systems, in particular when using assume-guarantee reasoning, we need to be able to close (sub-)systems, which is commonly done by adding an environment process. For models with asynchronous

  5. Reflecting on the structure of soil classification systems: insights from a proposal for integrating subsoil data into soil information systems

    Science.gov (United States)

    Dondeyne, Stefaan; Juilleret, Jérôme; Vancampenhout, Karen; Deckers, Jozef; Hissler, Christophe

    2017-04-01

    Classification of soils in both World Reference Base for soil resources (WRB) and Soil Taxonomy hinges on the identification of diagnostic horizons and characteristics. However as these features often occur within the first 100 cm, these classification systems convey little information on subsoil characteristics. An integrated knowledge of the soil, soil-to-substratum and deeper substratum continuum is required when dealing with environmental issues such as vegetation ecology, water quality or the Critical Zone in general. Therefore, we recently proposed a classification system of the subsolum complementing current soil classification systems. By reflecting on the structure of the subsoil classification system which is inspired by WRB, we aim at fostering a discussion on some potential future developments of WRB. For classifying the subsolum we define Regolite, Saprolite, Saprock and Bedrock as four Subsolum Reference Groups each corresponding to different weathering stages of the subsoil. Principal qualifiers can be used to categorize intergrades of these Subsoil Reference Groups while morphologic and lithologic characteristics can be presented with supplementary qualifiers. We argue that adopting a low hierarchical structure - akin to WRB and in contrast to a strong hierarchical structure as in Soil Taxonomy - offers the advantage of having an open classification system avoiding the need for a priori knowledge of all possible combinations which may be encountered in the field. Just as in WRB we also propose to use principal and supplementary qualifiers as a second level of classification. However, in contrast to WRB we propose to reserve the principal qualifiers for intergrades and to regroup the supplementary qualifiers into thematic categories (morphologic or lithologic). Structuring the qualifiers in this manner should facilitate the integration and handling of both soil and subsoil classification units into soil information systems and calls for paying

  6. Behaviour of transuranic radionuclides in soils, plants and soil-plant system

    International Nuclear Information System (INIS)

    Vyas, B.N.; Mistry, K.B.

    1996-01-01

    The present paper reviews the investigations undertaken to elucidate the physicochemical, edaphic and physiological aspects of the behaviour of long-lived transuranic radionuclides 239 Pu and 241 Am in typical Indian soils and soil-plant systems. 23 refs

  7. A sensor-less methanol concentration control system based on feedback from the stack temperature

    International Nuclear Information System (INIS)

    An, Myung-Gi; Mehmood, Asad; Ha, Heung Yong

    2014-01-01

    Highlights: • A new sensor-less methanol control algorithm based on feedback from the stack temperature is developed. • Feasibility of the algorithm is tested using a DMFC system with a recirculating fuel loop. • The algorithm precisely controls the methanol concentration without the use of methanol sensors. • The sensor-less controller shortens the time that the DMFC system requires to go from start-up to steady-state. • This controller is effective in handling unexpected changes in the methanol concentration and stack temperature. - Abstract: A sensor-less methanol concentration control system based on feedback from the stack temperature (SLCCF) has been developed. The SLCCF algorithm is embedded into an in-house LabVIEW program that has been developed to control the methanol concentration in the feed of direct methanol fuel cells (DMFCs). This control method utilizes the close correlation between the stack temperature and the methanol concentration in the feed. Basically, the amounts of methanol to be supplied to the re-circulating feed stream are determined by estimating the methanol consumption rates under given operating conditions, which are then adjusted by a proportional–integral controller and supplied into the feed stream to maintain the stack temperature at a set value. The algorithm is designed to control the methanol concentration and the stack temperature for both start-up and normal operation processes. Feasibility tests with a 200 W-class DMFC system under various operating conditions confirm that the algorithm successfully maintains the methanol concentration in the feed as well as the stack temperature at set values, and the start-up time required for the DMFC system to reach steady-state operating conditions is reduced significantly compared with conventional sensor-less methods

  8. Beach Advisory and Closing Online Notification (BEACON) system

    Science.gov (United States)

    Beach Advisory and Closing Online Notification system (BEACON) is a colletion of state and local data reported to EPA about beach closings and advisories. BEACON is the public-facing query of the Program tracking, Beach Advisories, Water quality standards, and Nutrients database (PRAWN) which tracks beach closing and advisory information.

  9. Incremental Closed-loop Identification of Linear Parameter Varying Systems

    DEFF Research Database (Denmark)

    Bendtsen, Jan Dimon; Trangbæk, Klaus

    2011-01-01

    , closed-loop system identification is more difficult than open-loop identification. In this paper we prove that the so-called Hansen Scheme, a technique known from linear time-invariant systems theory for transforming closed-loop system identification problems into open-loop-like problems, can be extended...

  10. Indicators of health system coverage and activity in Ireland during the economic crisis 2008-2014 - from 'more with less' to 'less with less'.

    LENUS (Irish Health Repository)

    Burke, Sara

    2014-09-01

    A new Irish government came to power in March 2011 with the most radical proposals for health system reform in the history of the state, including improving access to healthcare, free GP care for all by 2015 and the introduction of Universal Health Insurance after 2016. All this was to be achieved amidst the most severe economic crisis experienced by Ireland since the 1930s. The authors assess how well the system coped with a downsizing of resources by an analysis of coverage and health system activity indicators. These show a health system that managed \\'to do more with less\\' from 2008 to 2012. They also demonstrate a system that was \\'doing more with less\\' by transferring the cost of care onto people and by significant resource cuts. From 2013, the indicators show a system that has no choice but \\'to do less with less\\' with diminishing returns from crude cuts. This is evident in declining numbers with free care, of hospital cases and home care hours, alongside increased wait-times and expensive agency staffing. The results suggest a limited window of benefit from austerity beyond which cuts and rationing prevail which is costly, in both human and financial terms.

  11. Remediation of a radioactively contaminated soil using a mobile soil-washing system

    International Nuclear Information System (INIS)

    Grant, D.C.; Lahoda, E.J.; Dietrich, A.J.; Weigle, D.H.; Keegan, C.P.; Sachse, J.D.

    1993-01-01

    In order to obtain free-release of a former uranium mining site in Texas, it was required that the surface soil meet specific radiological guidelines. The soil has been contaminated with uranium and radium as a result of the spillage of well-drilling material, process solutions, and ion exchange resins during mining. To meet the required guidelines, the contaminated soil had to be either removed and disposed of off-site or remediated. For economic and long-term liability reasons, remediation of the soil by soil washing was performed. The remediation of this site utilizing the Scientific Ecology Group's soil washing system is discussed in this paper

  12. Increasing Soil Organic Matter Enhances Inherent Soil Productivity while Offsetting Fertilization Effect under a Rice Cropping System

    Directory of Open Access Journals (Sweden)

    Ya-Nan Zhao

    2016-09-01

    Full Text Available Understanding the role of soil organic matter (SOM in soil quality and subsequent crop yield and input requirements is useful for agricultural sustainability. SOM is widely considered to affect a wide range of soil properties, however, great uncertainty still remains in identifying the relationships between SOM and crop yield due to the difficulty in separating the effect of SOM from other yield-limiting factors. Based on 543 on-farm experiments, where paired treatments with and without NPK fertilizer were conducted during 2005–2009, we quantified the inherent soil productivity, fertilization effect, and their contribution to rice yield and further evaluated their relationships with SOM contents under a rice cropping system in the Sichuan Basin of China. The inherent soil productivity assessed by rice grain yield under no fertilization (Y-CK was 5.8 t/ha, on average, and contributed 70% to the 8.3 t/ha of rice yield under NPK fertilization (Y-NPK while the other 30% was from the fertilization effect (FE. No significant correlation between SOM content and Y-NPK was observed, however, SOM content positively related to Y-CK and its contribution to Y-NPK but negatively to FE and its contribution to Y-NPK, indicating an increased soil contribution but a decreased fertilizer contribution to rice yield with increasing SOM. There were significantly positive relationships between SOM and soil available N, P, and K, indicating the potential contribution of SOM to inherent soil productivity by supplying nutrients from mineralization. As a result, approaches for SOM accumulation are practical to improve the inherent soil productivity and thereafter maintain a high crop productivity with less dependence on chemical fertilizers, while fertilization recommendations need to be adjusted with the temporal and spatial SOM variation.

  13. Enzyme pretreatment of fats, oil and grease from restaurant waste to prolong septic soil treatment system effectiveness.

    Science.gov (United States)

    Dong, Younsuk; Safferman, Steven I; Ostahowski, Jeff; Herold, Tom; Panter, Ronald

    2017-01-02

    When a fast-food restaurant's wastewater containing fats, oil and grease (FOG) is discharged into a collection system, it builds up over time and clogs pipes. Similarly, when such wastewater flows into a septic soil treatment system, it adheres to the surface of inlet pipes, gravel/distribution media and soil, restricting the flow and eventually clogging the septic soil treatment system. In this study, an enzymatic pretreatment system was tested on wastewater from a fast-food restaurant to determine its effectiveness in preventing septic soil treatment system clogging. This system used aeration equipment, baffles and a one-time inoculum that excretes enzymes to reduce the molecular weight and number of double bonds associated with FOG. FOG containing triglycerides having lower molecular weights and fewer double bonds are less sticky. The enzymatic pretreatment system was found to cause these changes as verified by measuring the types of triglycerides (compounds in FOG) using liquid chromatography/mass spectrometry. A unique bench-scale septic soil treatment system (soil trench) was also used. Each contained six soil moisture sensors to enable the determination of moisture saturation trends among the five tested conditions: sanitary wastewater only, a combination of sanitary and kitchen wastewater, enzymatically pretreated sanitary and kitchen wastewater, kitchen wastewater, and enzymatically pretreated kitchen wastewater. For all influent types, a significant amount of FOG and other pollutants were removed, regardless of the initial concentrations. Moisture sensor readings showed differences among the tested conditions, indicating that septic soil treatment system clogging was delayed. Inspection of the influent pipe and gravel at the end of testing verified these differences as did the measurements of volatile solids.

  14. Beach Advisory and Closing Online Notification (BEACON) system

    Data.gov (United States)

    U.S. Environmental Protection Agency — Beach Advisory and Closing Online Notification system (BEACON) is a colletion of state and local data reported to EPA about beach closings and advisories. BEACON is...

  15. Quantifying the contribution of the root system of alpine vegetation in the soil aggregate stability of moraine

    Directory of Open Access Journals (Sweden)

    Csilla Hudek

    2017-03-01

    stability was significantly increased by the presence of roots. The lowest soil aggregate stability was found with Epilobium fleischeri followed by Minuartia recurva and Leucanthemopsis alpina. The highest aggregate stability was found with the graminoid species. These results show a close relationship between the development of root systems of the studied species and soil aggregate stability, a factor which can be taken into consideration in order to improve the accuracy of existing susceptibility mapping for early warning and civilian protection.

  16. Soil Erodibility Parameters Under Various Cropping Systems of Maize

    Science.gov (United States)

    van Dijk, P. M.; van der Zijp, M.; Kwaad, F. J. P. M.

    1996-08-01

    For four years, runoff and soil loss from seven cropping systems of fodder maize have been measured on experimental plots under natural and simulated rainfall. Besides runoff and soil loss, several variables have also been measured, including rainfall kinetic energy, degree of slaking, surface roughness, aggregate stability, soil moisture content, crop cover, shear strength and topsoil porosity. These variables explain a large part of the variance in measured runoff, soil loss and splash erosion under the various cropping systems. The following conclusions were drawn from the erosion measurements on the experimental plots (these conclusions apply to the spatial level at which the measurements were carried out). (1) Soil tillage after maize harvest strongly reduced surface runoff and soil loss during the winter; sowing of winter rye further reduced winter erosion, though the difference with a merely tilled soil is small. (2) During spring and the growing season, soil loss is reduced strongly if the soil surface is partly covered by plant residues; the presence of plant residue on the surface appeared to be essential in achieving erosion reduction in summer. (3) Soil loss reductions were much higher than runoff reductions; significant runoff reduction is only achieved by the straw system having flat-lying, non-fixed plant residue on the soil surface; the other systems, though effective in reducing soil loss, were not effective in reducing runoff.

  17. 21 CFR 886.5820 - Closed-circuit television reading system.

    Science.gov (United States)

    2010-04-01

    ... reading system. (a) Identification. A closed-circuit television reading system is a device that consists of a lens, video camera, and video monitor that is intended for use by a patient who has subnormal... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Closed-circuit television reading system. 886.5820...

  18. Follow up of the evolution of a soil-plant system using the neutrongraphic technique

    International Nuclear Information System (INIS)

    Fontes, L.; Crispim, V.R.; Lima, C.T.S.

    2009-01-01

    In the Brazilian northeast region, where semiarid climate prevails the soil low humidity, restricts the growth of the roots in the soil most superficial layer. A soil-plant system consisting of aluminum pots filled with soil similar to that found in the semiarid regions was designed to follow the growth of corn and soy roots. There, the seeds are planted together with artificial seeds of hydrogel and agave, which store part of the water from irrigation and later release it in conformity with the search of the roots. Nondestructive tests through the Thermal Neutron Radiography technique were conducted, exposing for 90 minutes the soilplant system, to the neutron flux from the J-9 irradiation channel of the Argonauta/IEN/CNEN reactor. An Industrex M radiographic film from Kodak and a gadolinium sheet converter, in close contact inside an aluminum chassis, were used to obtain the neutron radiography image. Lead plates, 1 mm thick, or aluminum plates, 1 cm thick, were placed to shield the gamma radiation of the neutron beam and thus allow a better visualization of the roots inside the soil. After expositions, the radiographic films were developed and the neutron radiographic images were digitalized with a Coolpix 995 Nikon camera. The neutron radiographic images were also digitally processed using the Image Pro Plus program, version 6.2. the use of lead and aluminum filters and with the use of digital processing techniques, allowed the visualization of the main and secondary roots, even when hidden by 10 mm thick humid soil. (author)

  19. Follow up of the evolution of a soil-plant system using the neutrongraphic technique

    Energy Technology Data Exchange (ETDEWEB)

    Fontes, L.; Crispim, V.R.; Lima, C.T.S., E-mail: luciano_rural@yahoo.com.b, E-mail: clima@con.ufrj.b, E-mail: verginia@con.ufrj.b [Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear; Ferreira, F.J., E-mail: fferreira@ien.gov.b [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2009-07-01

    In the Brazilian northeast region, where semiarid climate prevails the soil low humidity, restricts the growth of the roots in the soil most superficial layer. A soil-plant system consisting of aluminum pots filled with soil similar to that found in the semiarid regions was designed to follow the growth of corn and soy roots. There, the seeds are planted together with artificial seeds of hydrogel and agave, which store part of the water from irrigation and later release it in conformity with the search of the roots. Nondestructive tests through the Thermal Neutron Radiography technique were conducted, exposing for 90 minutes the soilplant system, to the neutron flux from the J-9 irradiation channel of the Argonauta/IEN/CNEN reactor. An Industrex M radiographic film from Kodak and a gadolinium sheet converter, in close contact inside an aluminum chassis, were used to obtain the neutron radiography image. Lead plates, 1 mm thick, or aluminum plates, 1 cm thick, were placed to shield the gamma radiation of the neutron beam and thus allow a better visualization of the roots inside the soil. After expositions, the radiographic films were developed and the neutron radiographic images were digitalized with a Coolpix 995 Nikon camera. The neutron radiographic images were also digitally processed using the Image Pro Plus program, version 6.2. the use of lead and aluminum filters and with the use of digital processing techniques, allowed the visualization of the main and secondary roots, even when hidden by 10 mm thick humid soil. (author)

  20. Soil organic phosphorus in soils under different land use systems in northeast Germany

    Science.gov (United States)

    Slazak, Anna; Freese, Dirk; Hüttl, Reinhard F.

    2010-05-01

    Phosphorus (P) is commonly known as a major plant nutrient, which can act as a limiting factor for plant growth in many ecosystems, including different land use systems. Organic P (Po), transformations in soil are important in determining the overall biological availability of P and additionally Po depletion is caused by land cultivation. It is expected that changes of land use modifies the distribution of soil P among the various P-pools (Ptotal, Plabile, Po), where the Plabile forms are considered to be readily available to plants and Po plays an important role with P nutrition supply for plants. The aim of the study was to measure the different soil P pools under different land use systems. The study was carried out in northeast of Brandenburg in Germany. Different land use systems were studied: i) different in age pine-oak mixed forest stands, ii) silvopastoral land, iii) arable lands. Samples were taken from two mineral soil layers: 0-10 and 10-20 cm. Recently, a variety of analytical methods are available to determine specific Po compounds in soils. The different P forms in the soil were obtained by a sequential P fractionation by using acid and alkaline extractants, which mean that single samples were subjected to increasingly stronger extractants, consequently separating the soil P into fractions based on P solubility. The soil Ptotal for the forest stands ranged from 100 to 183 mg kg -1 whereas Po from 77 to 148 mg kg -1. The Po and Plabile in both soil layers increased significantly with increase of age-old oak trees. The most available-P fraction was Plabile predominate in the oldest pine-oak forest stand, accounting for 29% of soil Ptotal. For the silvopasture and arable study sites the Ptotal content was comparable. However, the highest value of Ptotal was measured in the 30 years old silvopastoral system with 685 mg kg-1 and 728 mg kg-1 at 0-10 cm and 10-20 cm depth, respectively than in arable lands. The results have shown that the 30 years old

  1. High rate reactive sputtering in an opposed cathode closed-field unbalanced magnetron sputtering system

    Science.gov (United States)

    Sproul, William D.; Rudnik, Paul J.; Graham, Michael E.; Rohde, Suzanne L.

    1990-01-01

    Attention is given to an opposed cathode sputtering system constructed with the ability to coat parts with a size up to 15 cm in diameter and 30 cm in length. Initial trials with this system revealed very low substrate bias currents. When the AlNiCo magnets in the two opposed cathodes were arranged in a mirrored configuration, the plasma density at the substrate was low, and the substrate bias current density was less than 1 mA/sq cm. If the magnets were arranged in a closed-field configuration where the field lines from one set of magnets were coupled with the other set, the substrate bias current density was as high as 5.7 mA/sq cm when NdFeB magnets were used. In the closed-field configuration, the substrate bias current density was related to the magnetic field strength between the two cathodes and to the sputtering pressure. Hard well-adhered TiN coatings were reactively sputtered in the opposed cathode system in the closed-field configuration, but the mirrored configuration produced films with poor adhesion because of etching problems and low plasma density at the substrate.

  2. Active fault diagnosis in closed-loop uncertain systems

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik

    2006-01-01

    Fault diagnosis of parametric faults in closed-loop uncertain systems by using an auxiliary input vector is considered in this paper, i.e. active fault diagnosis (AFD). The active fault diagnosis is based directly on the socalled fault signature matrix, related to the YJBK (Youla, Jabr, Bongiorno...... and Kucera) parameterization. Conditions are given for exact detection and isolation of parametric faults in closed-loop uncertain systems....

  3. The influence of rolled erosion control systems on soil temperature and surface albedo: part I. A greenhouse experiment

    International Nuclear Information System (INIS)

    Sutherland, R.A.; Menard, T.; Perry, J.L.; Penn, D.C.

    1998-01-01

    A greenhouse study examined the influences of various surface covers (a bare control soil and seven rolled erosion control systems—RECS) on surface radiative properties, and soil temperature. In our companion paper we examine relationships with soil moisture, biomass production, and nutrient assimilation. Randomization and replication were key components to our study of microclimate under tropical radiation conditions. The bare Oxisol control soil exhibited the most extreme microclimatic conditions with the lowest albedo (not significantly different from that of P300© North American Green, a dark green polypropylene system), and the highest mean and maximum hourly temperatures recorded at depths of 5 and 8 cm. This hostile climatic environment was not conducive to biomass production or moisture storage and it is likely that the observed soil surface crusts impeded plant emergence. Rolled erosion control systems, on the other hand, generally moderated soil temperatures by reflecting more shortwave radiation, implying less heat energy at the surface for conduction to the soil. The result was that RECS exhibited lower mean soil temperatures, higher minimum temperatures and lower maximum soil temperatures. An aspen excelsior system (Curlex I© Excelsior) had the highest albedo and the soil beneath this system exhibited the greatest temperature modulation. Open-weave systems composed of jute (Geojute© Price & Pictures) and coconut fibers (BioD-Mat 70© RoLanka) were the RECS most similar in temperature response to the bare control soil. Other systems examined were intermediate in their temperature response and surface albedo (i.e., SC150BN© North American Green, C125© North American Green and Futerra© Conwed Fibers). (author)

  4. Impact of Cropping Systems, Soil Inoculum, and Plant Species Identity on Soil Bacterial Community Structure.

    Science.gov (United States)

    Ishaq, Suzanne L; Johnson, Stephen P; Miller, Zach J; Lehnhoff, Erik A; Olivo, Sarah; Yeoman, Carl J; Menalled, Fabian D

    2017-02-01

    Farming practices affect the soil microbial community, which in turn impacts crop growth and crop-weed interactions. This study assessed the modification of soil bacterial community structure by organic or conventional cropping systems, weed species identity [Amaranthus retroflexus L. (redroot pigweed) or Avena fatua L. (wild oat)], and living or sterilized inoculum. Soil from eight paired USDA-certified organic and conventional farms in north-central Montana was used as living or autoclave-sterilized inoculant into steam-pasteurized potting soil, planted with Am. retroflexus or Av. fatua and grown for two consecutive 8-week periods to condition soil nutrients and biota. Subsequently, the V3-V4 regions of the microbial 16S rRNA gene were sequenced by Illumina MiSeq. Treatments clustered significantly, with living or sterilized inoculum being the strongest delineating factor, followed by organic or conventional cropping system, then individual farm. Living inoculum-treated soil had greater species richness and was more diverse than sterile inoculum-treated soil (observed OTUs, Chao, inverse Simpson, Shannon, P soil contained more Chloroflexi and Acidobacteria, while the sterile inoculum soil had more Bacteroidetes, Firmicutes, Gemmatimonadetes, and Verrucomicrobia. Organically farmed inoculum-treated soil had greater species richness, more diversity (observed OTUs, Chao, Shannon, P soil. Cyanobacteria were higher in pots growing Am. retroflexus, regardless of inoculum type, for three of the four organic farms. Results highlight the potential of cropping systems and species identity to modify soil bacterial communities, subsequently modifying plant growth and crop-weed competition.

  5. Soil carbon pools in different pasture systems

    Directory of Open Access Journals (Sweden)

    Francisco M. Cardozo, Jr.

    2016-03-01

    Full Text Available The aim of this study was to assess the carbon pools of a tropical soil where the native forest was replaced with different pasture systems. We studied five pasture production systems, including four monoculture systems with forage grasses such as Andropogon, Brachiaria, Panicum, and Cynodon, and an agroforestry system as well as a native vegetation plot. Greater availability of fulvic acid was detected in the agroforestry system as compared with that in the other systems. Higher lability of C was detected in the Andropogon system during the dry and rainy seasons and during the dry season in Cynodon. During the dry season, all pastures systems showed deficits in the net removal of atmospheric CO2. The structure and practices of the agroforestry system enables more carbon to be sequestered in the soil as compared with the monoculture pasture, suggesting that it is an important practice to mitigate climatic change and to improve soil quality.

  6. STABILITY OF SATELLITES IN CLOSELY PACKED PLANETARY SYSTEMS

    International Nuclear Information System (INIS)

    Payne, Matthew J.; Holman, Matthew J.; Deck, Katherine M.; Perets, Hagai B.

    2013-01-01

    We perform numerical integrations of four-body (star, planet, planet, satellite) systems to investigate the stability of satellites in planetary systems with tightly packed inner planets (STIPs). We find that the majority of closely spaced stable two-planet systems can stably support satellites across a range of parameter-space which is only slightly decreased compared to that seen for the single-planet case. In particular, circular prograde satellites remain stable out to ∼0.4 R H (where R H is the Hill radius) as opposed to 0.5 R H in the single-planet case. A similarly small restriction in the stable parameter-space for retrograde satellites is observed, where planetary close approaches in the range 2.5-4.5 mutual Hill radii destabilize most satellites orbits only if a ∼ 0.65 R H . In very close planetary pairs (e.g., the 12:11 resonance) the addition of a satellite frequently destabilizes the entire system, causing extreme close approaches and the loss of satellites over a range of circumplanetary semi-major axes. The majority of systems investigated stably harbored satellites over a wide parameter-space, suggesting that STIPs can generally offer a dynamically stable home for satellites, albeit with a slightly smaller stable parameter-space than the single-planet case. As we demonstrate that multi-planet systems are not a priori poor candidates for hosting satellites, future measurements of satellite occurrence rates in multi-planet systems versus single-planet systems could be used to constrain either satellite formation or past periods of strong dynamical interaction between planets

  7. Effect of biosurfactants on crude oil desorption and mobilization in a soil system

    Energy Technology Data Exchange (ETDEWEB)

    Kuyukina, M.S.; Ivshina, I.B. [Ural Branch of the Russian Academy of Sciences, Perm (Russian Federation). Institute of Ecology and Genetics of Microorganisms; Makarov, S.O.; Litvinenko, L.V. [Perm State University, Perm (Russian Federation); Cunningham, C.J. [University of Edinburgh (United Kingdom). Contaminated Land Assessment and Remediation Research Centre; Philp, J.C. [Napier University, Edinburgh (United Kingdom). School of Life Sciences

    2005-02-01

    Microbially produced biosurfactants were studied to enhance crude oil desorption and mobilization in model soil column systems. The ability of biosurfactants from Rhodococcus ruber to remove the oil from the soil core was 1.4-2.3 times greater than that of a synthetic surfactant of suitable properties, Tween 60. Biosurfactant-enhanced oil mobilization was temperature-related, and it was slower at 15{sup o}C than at 22-28{sup o}C. Mathematical modelling using a one-dimensional filtration model was applied to simulate the process of oil penetration through a soil column in the presence of (bio)surfactants. A strong positive correlation (R{sup 2} = 0.99) was found between surfactant penetration through oil-contaminated soil and oil removal activity. Biosurfactant was less adsorbed to soil components than synthetic surfactant, thus rapidly penetrating through the soil column and effectively removing 65-82% of crude oil. Chemical analysis showed that crude oil removed by biosurfactant contained a lower proportion of high-molecular-weight paraffins and asphaltenes, the most nonbiodegradable compounds, compared to initial oil composition. This result suggests that oil mobilized by biosurfactants could be easily biodegraded by soil bacteria. Rhodococcus biosurfactants can be used for in situ remediation of oil-contaminated soils. (author)

  8. Stalagmite carbon isotopes and dead carbon proportion (DCP) in a near-closed-system situation: An interplay between sulphuric and carbonic acid dissolution

    Science.gov (United States)

    Bajo, Petra; Borsato, Andrea; Drysdale, Russell; Hua, Quan; Frisia, Silvia; Zanchetta, Giovanni; Hellstrom, John; Woodhead, Jon

    2017-08-01

    In this study, the 'dead carbon proportion' (DCP) calculated from combined U-Th and radiocarbon analyses was used to explore the carbon isotope systematics in Corchia Cave (Italy) speleothems, using the example of stalagmite CC26 which grew during the last ∼12 ka. The DCP values in CC26 are among the highest ever recorded in a stalagmite, spanning the range 44.8-68.8%. A combination of almost closed-system conditions and sulphuric acid dissolution (SAD) are proposed as major drivers in producing such a high DCP with minor contribution from old organic matter from the deep vadose zone. The long-term decrease in both DCP and δ13C most likely reflects post-glacial soil recovery above the cave, with a progressive increase of soil CO2 contribution to the total dissolved inorganic carbon (DIC). Pronounced millennial-scale shifts in DCP and relatively small coeval but antipathetic changes in δ13C are modulated by the effects of hydrological variability on open and closed-system dissolution, SAD and prior calcite precipitation. Hence, the DCP in Corchia Cave speleothems represents an additional proxy for rainfall amount.

  9. Testing the effect of a microbial-based soil amendment on aggregate stability and erodibility

    DEFF Research Database (Denmark)

    Malozo, Mponda; Iversen, Bo Vangsø; Heckrath, Goswin Johann

    to the rainfall-runoff experiment where the microbial-based product had a clear effect on soil erodibility. In relation to measurement of aggregate stability as well as clay dispersion, the picture was less clear. Especially for the sandy Tanzania soil with a low content of organic matter, a clear effect was seen...... aggregate stability and erodibility. Two commercial products, gypsum and a microbial-based solution were used for the experiment and were tested on two Danish sandy loamy soils as well on a sandy soil from Tanzania. The carrier of the microbial-based product, a glycerol solution, was tested as well....... In the laboratory, soils were treated with the soil amendments in a two-step procedure at controlled water contents following aerobic incubation in closed containers. Water-aggregate stability and clay dispersion were measured on soil aggregates less than 8 mm in diameter. Aggregate stability was measured...

  10. The Effects of Different Tillage Systems on Soil Hydrology and Erosion in Southeastern Brazil

    Science.gov (United States)

    Bertolino, A. V. F. A.; Fernandes, N. F.; Souza, A. P.; Miranda, J. P.; Rocha, M. L.

    2009-04-01

    Conventional tillage usually imposes a variety of modifications on soil properties that can lead to important changes in the type and magnitude of the hydrological processes that take place at the upper portion of the soil profile. Plough pan formation, for example, is considered to be an important consequence of conventional tillage practices in southeastern Brazil, decreasing infiltration rates and contributing to soil erosion, especially in steep slopes. In order to characterize the changes in soil properties and soil hydrology due to the plough pan formation we carried out detailed investigations in two experimental plots in Paty do Alferes region, located in the hilly landscape of Serra do Mar in southeastern Brazil, close to Rio de Janeiro city. Farming activities are very important in this area, in particular the ones related to the tomato production. The local hilly topography with short and steep hillslopes, as well as an average annual rainfall of almost 2000 mm, favor surface runoff and the evolution of rill and gully erosion. The two runoff plots are 22m long by 4m wide and were installed side by side along a representative hillslope, both in terms of soil (Oxisol) and steepness. At the lower portion of each plot there is a collecting trough connected by a PVC pipe to a 500 and 1000 liters sediment storage boxes. Soil tillage treatments used in the two plots were: Conventional Tillage (CT), with one plowing using disc-type plow (about 18 cm depth) and one downhill tractor leveling, in addition to burning residues from previous planting; and Minimum Tillage (MT), which did not allow burning residues from previous planting and preserved a vegetative cover between plantation lines. Runoff and soil erosion measurements were carried out in both plots immediately after each rainfall event. In order to characterize soil water movements under the two tillage systems (CT and MT), 06 nests of tensiometers and 04 nests of Watermark sensors were installed in each

  11. Portable DMFC system with methanol sensor-less control

    Energy Technology Data Exchange (ETDEWEB)

    Chen, C.Y.; Liu, D.H.; Huang, C.L.; Chang, C.L. [Institute of Nuclear Energy Research (INER), No. 1000, Wunhua Rd., Jiaan Village, Longtan Township, Taoyuan County 32546 (China)

    2007-05-15

    This work develops a prototype 20 W portable DMFC by system integration of stack, condenser, methanol sensor-less control and start-up characteristics. The effects of these key components and control schemes on the performance are also discussed. To expedite the use of portable DMFC in electronic applications, the system utilizes a novel methanol sensor-less control method, providing improved fuel efficiency, durability, miniaturization and cost reduction. The operating characteristics of the DMFC stack are applied to control the fuel ejection time and period, enabling the system to continue operating even when the MEAs of the stack are deteriorated. The portable system is also designed with several features including water balance and quick start-up (in 5 min). Notably, the proposed system using methanol sensor-less control with injection of pure methanol can power the DVD player and notebook PC. The system specific energy and energy density following three days of operation are 362 Wh kg{sup -1} and 335 Wh L{sup -1}, respectively, which are better than those of lithium batteries ({proportional_to}150 Wh kg{sup -1} and {proportional_to}250 Wh L{sup -}). This good energy storage feature demonstrates that the portable DMFC is likely to be valuable in computer, communication and consumer electronic (3C) markets. (author)

  12. Targeting the environmental assessment of veterinary drugs with the multi-species-soil system (MS{center_dot}3) agricultural soil microcosms: the ivermectin case study

    Energy Technology Data Exchange (ETDEWEB)

    Carbonell-Martin, G.; Pro-Gonzalez, J.; Aragones-Grunert, P.; Babib-Vich, M. M.; Fernandez-Rorija, C.; Tarazona-Lafarga, J. V.

    2011-07-01

    The environmental risk assessment of the veterinary pharmaceutical ivermectin is receiving significant attention. This paper assesses the capacity of the MS{center_dot}3 soil microcosm as a tool for targeting the environmental impact assessment of veterinary drugs, using ivermectin as model. Two screening MS{center_dot}3 were performed using different European soils; one with a soil collected in an agricultural station near to Madrid, Spain and a second with a soil collected in a farm area close to York, UK. Soils were fortified with ivermectin at the following ranges: 0.01-10 mg kg{sup -}1 and 0.1-100 mg kg{sup -}1 in the Madrid and York studies, respectively. The effects on earthworms, plants and soil microorganisms were assessed in the Madrid soil. Toxicity tests on aquatic organisms (algae, cladocerans and in vitro fish cell line RTLW1) were also conducted with the leachates. No effects were observed in earthworms and plants at any tested concentration; reduction in the respiration rate (< 5%) of soil microorganisms was detected. Earthworm/soil bioconcentration factors decreased with the increase in soil concentrations and were higher for the York soil. Effects on daphnids were observed in tested leachates; based on measured levels of ivermectin in the leachates an EC50 of about 0.5{mu}gL{sup -}1 can be estimated. Comparisons based on toxicity data and equilibrium partitioning confirmed that the main risk is expected to be related to the high sensitivity of cladocerans. The results confirm that MS{center_dot}3 systems are cost-effective tools for assessing the impact of veterinary pharmaceuticals when applied to agricultural land, as previously demonstrated for antimicrobials. (Author) 39 refs.

  13. Effects of manure and mineral fertilization strategies on soil antibiotic resistance gene levels and microbial community in a paddy–upland rotation system

    International Nuclear Information System (INIS)

    Lin, Hui; Sun, Wanchun; Zhang, Zulin; Chapman, Stephen J.; Freitag, Thomas E.; Fu, Jianrong; Zhang, Xin; Ma, Junwei

    2016-01-01

    This work investigated the responses of antibiotic resistance genes (ARGs) and the soil microbial community in a paddy–upland rotation system to mineral fertilizer (NPK) and different application dosages of manure combined with NPK. The occurrence of five tetracycline ARGs (tetA, tetB, tetC, tetG and tetW), two sulfonamide ARGs (sul1 and sul2) and one genetic element (IntI1) was quantified. NPK application showed only slight or no impact on soil ARGs abundances compared with the control without fertilizer. Soil ARGs abundances could be increased by manure-NPK application but was related to manure dosage (2250–9000 kg ha"−"1). Principal component analysis (PCA) showed that the soil ARG profile of the treatment with 9000 kg ha"−"1 manure separated clearly from the other treatments; the ARGs that contributed most to the discrimination of this treatment were tetA, tetG, tetW, sul1, sul2 and IntI1. Community level physiological profile (CLPP) analysis showed that increasing manure dosage from 4500 kg ha"−"1 to 9000 kg ha"−"1 induced a sharp increase in almost all of the detected ARGs but would not change the microbial community at large. However, 9000 kg ha"−"1 manure application produced a decline in soil microbial activity. Determination of antibiotics and heavy metals in soils suggested that the observed bloom of soil ARGs might associate closely with the accumulation of copper and zinc in soil. - Highlights: • The occurrence of ten ARGs in a manure and a paddy soil from China was tested. • The fate of ARGs in soil varied between ARG types and fertilization strategies. • The increase in soil ARG caused by manure-NPK fertilization was manure dosage-related. • Excessive manure greatly increased soil ARGs and inhibited soil microbial activity. • Cu and Zn levels in soils associated closely with the observed soil ARGs bloom. - The elevation of soil ARGs abundances in soil caused by manure application combined with NPK in a paddy

  14. Genesis Eco Systems, Inc. soil washing process

    International Nuclear Information System (INIS)

    Cena, R.J.

    1994-01-01

    The Genesis soil washing system is an integrated system of modular design allowing for maximum material handling capabilities, with optimized use of space for site mobility. The Surfactant Activated Bio-enhanced Remediation Equipment-Generation 1 (SABRE-1, Patent Applied For) modification was developed specifically for removing petroleum byproducts from contaminated soils. Scientifically formulated surfactants, introduced by high pressure spray nozzles, displace the contaminant from the surface of the soil particles into the process solution. Once the contaminant is dispersed into the liquid fraction of the process, it is either mechanically removed, chemically oxidized, or biologically oxidized. The contaminated process water is pumped through the Genesis Biosep (Patent Applied For) filtration system where the fines portion is flocculated, and the contaminant-rich liquid portion is combined with an activated mixture of nutrients and carefully selected bacteria to decompose the hydrocarbon fraction. The treated soil and dewatered fines are transferred to a bermed stockpile where bioremediation continues during drying. The process water is reclaimed, filtered, and recycled within the system

  15. Cascaded recompression closed brayton cycle system

    Energy Technology Data Exchange (ETDEWEB)

    Pasch, James J.

    2018-01-02

    The present disclosure is directed to a cascaded recompression closed Brayton cycle (CRCBC) system and method of operation thereof, where the CRCBC system includes a compressor for compressing the system fluid, a separator for generating fluid feed streams for each of the system's turbines, and separate segments of a heater that heat the fluid feed streams to different feed temperatures for the system's turbines. Fluid exiting each turbine is used to preheat the fluid to the turbine. In an embodiment, the amount of heat extracted is determined by operational costs.

  16. Cascaded recompression closed brayton cycle system

    Science.gov (United States)

    Pasch, James J.

    2018-01-02

    The present disclosure is directed to a cascaded recompression closed Brayton cycle (CRCBC) system and method of operation thereof, where the CRCBC system includes a compressor for compressing the system fluid, a separator for generating fluid feed streams for each of the system's turbines, and separate segments of a heater that heat the fluid feed streams to different feed temperatures for the system's turbines. Fluid exiting each turbine is used to preheat the fluid to the turbine. In an embodiment, the amount of heat extracted is determined by operational costs.

  17. Revised Soil Classification System for Coarse-Fine Mixtures

    KAUST Repository

    Park, Junghee; Santamarina, Carlos

    2017-01-01

    Soil classification systems worldwide capture great physical insight and enable geotechnical engineers to anticipate the properties and behavior of soils by grouping them into similar response categories based on their index properties. Yet gravimetric analysis and data trends summarized from published papers reveal critical limitations in soil group boundaries adopted in current systems. In particular, current classification systems fail to capture the dominant role of fines on the mechanical and hydraulic properties of soils. A revised soil classification system (RSCS) for coarse-fine mixtures is proposed herein. Definitions of classification boundaries use low and high void ratios that gravel, sand, and fines may attain. This research adopts emax and emin for gravels and sands, and three distinctive void ratio values for fines: soft eF|10  kPa and stiff eF|1  MPa for mechanical response (at effective stress 10 kPa and 1 MPa, respectively), and viscous λ⋅eF|LL for fluid flow control, where λ=2log(LL−25) and eF|LL is the void ratio at the liquid limit. For classification purposes, these void ratios can be estimated from index properties such as particle shape, the coefficient of uniformity, and the liquid limit. Analytically computed and data-adjusted boundaries are soil-specific, in contrast with the Unified Soil Classification System (USCS). Threshold fractions for mechanical control and for flow control are quite distinct in the proposed system. Therefore, the RSCS uses a two-name nomenclature whereby the first letters identify the component(s) that controls mechanical properties, followed by a letter (shown in parenthesis) that identifies the component that controls fluid flow. Sample charts in this paper and a Microsoft Excel facilitate the implementation of this revised classification system.

  18. Revised Soil Classification System for Coarse-Fine Mixtures

    KAUST Repository

    Park, Junghee

    2017-04-17

    Soil classification systems worldwide capture great physical insight and enable geotechnical engineers to anticipate the properties and behavior of soils by grouping them into similar response categories based on their index properties. Yet gravimetric analysis and data trends summarized from published papers reveal critical limitations in soil group boundaries adopted in current systems. In particular, current classification systems fail to capture the dominant role of fines on the mechanical and hydraulic properties of soils. A revised soil classification system (RSCS) for coarse-fine mixtures is proposed herein. Definitions of classification boundaries use low and high void ratios that gravel, sand, and fines may attain. This research adopts emax and emin for gravels and sands, and three distinctive void ratio values for fines: soft eF|10  kPa and stiff eF|1  MPa for mechanical response (at effective stress 10 kPa and 1 MPa, respectively), and viscous λ⋅eF|LL for fluid flow control, where λ=2log(LL−25) and eF|LL is the void ratio at the liquid limit. For classification purposes, these void ratios can be estimated from index properties such as particle shape, the coefficient of uniformity, and the liquid limit. Analytically computed and data-adjusted boundaries are soil-specific, in contrast with the Unified Soil Classification System (USCS). Threshold fractions for mechanical control and for flow control are quite distinct in the proposed system. Therefore, the RSCS uses a two-name nomenclature whereby the first letters identify the component(s) that controls mechanical properties, followed by a letter (shown in parenthesis) that identifies the component that controls fluid flow. Sample charts in this paper and a Microsoft Excel facilitate the implementation of this revised classification system.

  19. Closed-loop Identification for Control of Linear Parameter Varying Systems

    DEFF Research Database (Denmark)

    Bendtsen, Jan Dimon; Trangbæk, Klaus

    2014-01-01

    , closed- loop system identification is more difficult than open-loop identification. In this paper we prove that the so-called Hansen Scheme, a technique known from linear time-invariant systems theory for transforming closed-loop system identification problems into open-loop-like problems, can...

  20. Fly ash dynamics in soil-water systems

    International Nuclear Information System (INIS)

    Sharma, S.; Fulekar, M.H.; Jayalakshmi, C.P.

    1989-01-01

    Studies regarding the effluents and coal ashes (or fly ash) resulting from coal burning are numerous, but their disposal and interactions with the soil and water systems and their detailed environmental impact assessment with concrete status reports on a global scale are scanty. Fly ash dynamics in soil and water systems are reviewed. After detailing the physical composition of fly ash, physicochemical changes in soil properties due to fly ash amendment are summarized. Areas covered include texture and bulk density, moisture retention, change in chemical equilibria, and effects of fly ash on soil microorganisms. Plant growth in amended soils is discussed, as well as plant uptake and accumulation of trace elements. In order to analyze the effect of fly ash on the physicochemical properties of water, several factors must be considered, including surface morphology of fly ash, pH of the ash sluice water, pH adjustments, leachability and solubility, and suspended ash and settling. The dynamics of fly ash in water systems is important due to pollution of groundwater resources from toxic components such as trace metals. Other factors summarized are bioaccumulation and biomagnification, human health effects of contaminants, and the impact of radionuclides in fly ash. Future research needs should focus on reduction of the environmental impact of fly ash and increasing utilization of fly ash as a soil amendment. 110 refs., 2 figs., 10 tabs

  1. Effects of plough pan development on surface hydrology and on soil physical properties in Southeastern Brazilian plateau

    Science.gov (United States)

    Bertolino, Ana V. F. A.; Fernandes, Nelson F.; Miranda, João P. L.; Souza, Andréa P.; Lopes, Marcel R. S.; Palmieri, Francesco

    2010-10-01

    SummaryConventional tillage may impose changes in soil physical properties that lead to a decrease in soil physical quality. Although plough pan formation is considered to be an important consequence of conventional tillage practices in Southeastern Brazil, few studies have focused on its hydrological consequences. Detailed investigations in two experimental plots located in the hilly landscape of Serra do Mar close to Rio de Janeiro city were carried out to characterize the changes in soil physical properties and in soil hydrology due to plough pan formation. Conventional (CT) and minimum tillage (MT) practices were implemented in two plots for 3 years and soil matric potential (SMP) was monitored in each plot via nests of tensiometers and Watermark® sensors installed at different depths. Undisturbed soil blocks were collected for micromorphological analyses to quantify the total pore space in soils under CT and MT systems, and in soils under natural tropical forest. Results suggest that soils under the CT system developed a plough pan layer at about 20 cm depth that had 44% less total porosity as compared to surface conditions. It is shown that soils under the CT system tended to stay saturated for longer periods of time after each rainfall event. Besides, during intense rainy periods soils under the CT system may develop hydrologic conditions that favor lateral flows while soils under the MT system were still draining. Such hydrological responses may explain why average soil erosion rates measured for individual rainfall events under the CT system were about 2.5 times greater than the ones observed at MT. The results attested that conventional tillage in this area generated modifications in soil fabric, especially in pore-size distribution and connectivity, which induced important changes in soil hydrology and soil erosion. The agricultural practices used in this area, associated with the local steep hillslopes and intense rainfall events, are definitely not

  2. Composting of wine industry wastes and their use as a substrate for growing soil less ornamental plants

    Energy Technology Data Exchange (ETDEWEB)

    Carmona, E.; Moreno, M. T.; Aviles, M.; Ordovas, J.

    2012-11-01

    To study the process of composting of grape marc and test the resulting compost as a substrate for the cultivation of ornamental plants, six composting processes, with mixtures of dealcoholised grapevine marc and grape stalk (DM + GS) in a 1:1 ratio (v:v), were carried out in Seville (Spain) between 2000 and 2006. The duration of the composting ranged between 20 and 24 weeks in the Spring-Summer season. Weekly, temperature, pH, EC, N-NO{sub 3}{sup -} and N-NH{sub 4} +, were measured. The maximum temperatures reached values of 65-73 degree centigrade at a depth between 40 and 80 cm. The compost had a slightly alkaline pH, slightly salinity, high organic matter and total nitrogen contents. The final compost chemical composition in total elements showed values in the same range as those corresponding to plant material, except for Fe. The distribution in the size of the particles gives way to a total porous space that is close to the one considered as optimal in a substrate for soil less cropping. Pore size distribution showed a prevalence of big pores that produces unbalance in the water-air ratios, resulting in a material with a good aeration but with low water retention. The composts were tested as substrates for four ornamental species: geranium, petunia, carnation and gerbera. The results suggest that compost has no limiting characteristics for its use as a medium for the cultivation of ornamental plants in container, and can replace conventional substrates, such as peat and coconut fibre. (Author) 35 refs.

  3. Supernova explosions in close binary systems. Pt. 2

    International Nuclear Information System (INIS)

    Sutantyo, W.

    1975-01-01

    The effects of a spherically symmetric explosion on the runaway velocity of a close binary system with an initial circular orbit is considered. It is shown that the runaway velocity is completely determined by the final orbital parameters regardless of the initial condition. The galactic z distribution of the known massive X-ray binaries indicates that the runaway velocities of these systems are very probably smaller than approximately 100 km/s with the most likely values of approximately 25-50 km/s. Such runaway velocities can be obtained if the post-explosion eccentricities are less than approximately 0.25. This then has the concequence that the mass of the exploded star which produced the neutron stars in the massive X-ray binaries can in most cases not have been larger than approximately 7-8 M(S) with the most likely values of approximately 3-4 M(S) if the supergiants in these systems have mass (M 2 ) of approximately 20 M(S). For Cyg X-1, the upper mass limit of the exploded star is found to be approximately 16 M(S). For M 2 = 30 M(S) these upper limit becomes approximately 9-10 M(S) and 19 M(S) respectively. (orig.) [de

  4. Evolution in close binary systems

    International Nuclear Information System (INIS)

    Yungel'son, L.R.; Masevich, A.G.

    1983-01-01

    Duality is the property most typical of stars. If one investigates how prevalent double stars are, making due allowance for selection effects, one finds that as many as 90 percent of all stars are paired. Contrary to tradition it is single stars that are out of the ordinary, and as will be shown presently even some of these may have been formed by coalescence of the members of binary systems. This review deals with the evolution of close binaries, defined as double-star systems whose evolution entails exchange of material between the two components

  5. Smaller stomata require less severe leaf drying to close: A case study in Rosa hydrida

    DEFF Research Database (Denmark)

    Gebraegziabher, Habtamu Giday; Kjær, Katrine Heinsvig; Fanourakis, D.

    2013-01-01

    Stomata formed at high relative air humidity (RH) close less as leaf dries; an effect that varies depending on the genotype. We here quantified the contribution of each stomatal response characteristic to the higher water loss of high RH-grown plants, and assessed the relationship between response...... characteristics and intraspecific variation in stomatal size. Stomatal size (length multiplied by width), density and responsiveness to desiccation, as well as pore dimensions were analyzed in ten rose cultivars grown at moderate (60%) or high (85%) RH. Leaf morphological components and transpiration at growth...... conditions were also assessed. High growth RH resulted in thinner (11%) leaves with larger area. A strong positive genetic correlation of daytime and nighttime transpiration at either RH was observed. Stomatal size determined pore area (r = 0.7) and varied by a factor of two, as a result of proportional...

  6. An integrated GIS application system for soil moisture data assimilation

    Science.gov (United States)

    Wang, Di; Shen, Runping; Huang, Xiaolong; Shi, Chunxiang

    2014-11-01

    The gaps in knowledge and existing challenges in precisely describing the land surface process make it critical to represent the massive soil moisture data visually and mine the data for further research.This article introduces a comprehensive soil moisture assimilation data analysis system, which is instructed by tools of C#, IDL, ArcSDE, Visual Studio 2008 and SQL Server 2005. The system provides integrated service, management of efficient graphics visualization and analysis of land surface data assimilation. The system is not only able to improve the efficiency of data assimilation management, but also comprehensively integrate the data processing and analysis tools into GIS development environment. So analyzing the soil moisture assimilation data and accomplishing GIS spatial analysis can be realized in the same system. This system provides basic GIS map functions, massive data process and soil moisture products analysis etc. Besides,it takes full advantage of a spatial data engine called ArcSDE to effeciently manage, retrieve and store all kinds of data. In the system, characteristics of temporal and spatial pattern of soil moiture will be plotted. By analyzing the soil moisture impact factors, it is possible to acquire the correlation coefficients between soil moisture value and its every single impact factor. Daily and monthly comparative analysis of soil moisture products among observations, simulation results and assimilations can be made in this system to display the different trends of these products. Furthermore, soil moisture map production function is realized for business application.

  7. Estimating soil water-holding capacities by linking the Food and Agriculture Organization Soil map of the world with global pedon databases and continuous pedotransfer functions

    Science.gov (United States)

    Reynolds, C. A.; Jackson, T. J.; Rawls, W. J.

    2000-12-01

    Spatial soil water-holding capacities were estimated for the Food and Agriculture Organization (FAO) digital Soil Map of the World (SMW) by employing continuous pedotransfer functions (PTF) within global pedon databases and linking these results to the SMW. The procedure first estimated representative soil properties for the FAO soil units by statistical analyses and taxotransfer depth algorithms [Food and Agriculture Organization (FAO), 1996]. The representative soil properties estimated for two layers of depths (0-30 and 30-100 cm) included particle-size distribution, dominant soil texture, organic carbon content, coarse fragments, bulk density, and porosity. After representative soil properties for the FAO soil units were estimated, these values were substituted into three different pedotransfer functions (PTF) models by Rawls et al. [1982], Saxton et al. [1986], and Batjes [1996a]. The Saxton PTF model was finally selected to calculate available water content because it only required particle-size distribution data and results closely agreed with the Rawls and Batjes PTF models that used both particle-size distribution and organic matter data. Soil water-holding capacities were then estimated by multiplying the available water content by the soil layer thickness and integrating over an effective crop root depth of 1 m or less (i.e., encountered shallow impermeable layers) and another soil depth data layer of 2.5 m or less.

  8. Soil hydrology of agroforestry systems: Competition for water or positive tree-crops interactions?

    Science.gov (United States)

    Gerjets, Rowena; Richter, Falk; Jansen, Martin; Carminati, Andrea

    2017-04-01

    In dry periods during the growing season crops may suffer from severe water stress. The question arises whether the alternation of crop and tree strips might enhance and sustain soil water resources available for crops during drought events. Trees reduce wind exposure, decreasing the potential evapotranspiration of crops and soils; additionally hydraulic lift from the deep roots of trees to the drier top soil might provide additional water for shallow-rooted crops. To understand the above and belowground water relations of agroforestry systems, we measured soil moisture and soil water potential in crop strips as a function of distance to the trees at varying depth as well as meteorological parameters. At the agroforestry site Reiffenhausen, Lower Saxony, Germany, two different tree species are planted, each in one separated tree strip: willow breed Tordis ((Salix viminalis x Salix Schwerinii) x Salix viminalis) and poplar clone Max 1 (Populus nigra x Populus maximowiczii). In between the tree strips a crop strip of 24 m width was established with annual crop rotation, managed the same way as the reference site. During a drought period in May 2016 with less than 2 mm rain in four weeks, an overall positive effect on hydrological conditions of the agroforestry system was observed. The results show that trees shaded the soil surface, lowering the air temperature and further increasing the soil moisture in the crop strips compared to the reference site, which was located far from the trees. At the reference site the crops took up water in the upper soil (sunlight. The two tree species behaved differently. The poplar strips showed more marked diurnal changes in soil water potential, with fast drying during daytime and rewetting during nighttime. We suppose that the rewetting during nighttime was caused by hydraulic lift, which supports passively the drier upper soil with water from the wetter, lower soil layers. This experimental study shows the importance of above- and

  9. Numerical Analysis of Combined Well and Open-Closed Loops Geothermal (CWG) Systems

    Science.gov (United States)

    Park, Yu-Chul

    2016-04-01

    Open-loop geothermal heat pump (GHP) system and closed-loop heat pump systems have been used in Korea to reduce emission of greenhouse gases such as carbon dioxide (CO2). The GHP systems have the pros and cons, for example, the open-loop GHP system is good energy-efficient and the closed-loop GHP system requires minimum maintenance costs. The open-loop GHP system can be used practically only with large amount of groundwater supply. The closed-loop GHP system can be used with high costs of initial installation. The performance and efficiency of the GHP system depend on the characteristics of the GHP system itself in addition to the geologic conditions. To overcome the cons of open-loop or closed-loop GHP system, the combined well and open-closed loops geothermal (CWG) system was designed. The open-loop GHP system is surrounded with closed-loop GHP systems in the CWG system. The geothermal energy in closed-loop GHP systems is supplied by the groundwater pumped by the open-loop GHP system. In this study, 2 different types of the CWG systems (small aperture hybrid CWG system and large aperture CWG system) are estimated using numerical simulation models in the aspect of energy efficiency. This work was supported by the New & Renewable Energy Core Technology Program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP), granted financial resource from the Ministry of Trade, Industry & Energy, Republic of Korea. (No.20153030111120).

  10. [Changes of soil physical properties during the conversion of cropland to agroforestry system].

    Science.gov (United States)

    Wang, Lai; Gao, Peng Xiang; Liu, Bin; Zhong, Chong Gao; Hou, Lin; Zhang, Shuo Xin

    2017-01-01

    To provide theoretical basis for modeling and managing agroforestry systems, the influence of conversion of cropland to agroforestry system on soil physical properties was investigated via a walnut (Juglans regia)-wheat (Triticum aestivum) intercropping system, a wide spreading local agroforestry model in northern Weihe River of loess area, with the walnut and wheat monoculture systems as the control. The results showed that the improvement of the intercropping system on soil physical properties mainly appeared in the 0-40 cm soil layer. The intercropping system could prevent soil bulk density rising in the surface soil (0-20 cm), and the plow pan in the 20-40 cm soil layer could be significantly alleviated. The intercropping system had conti-nuous improvement on soil field capacity in each soil layer with the planting age increase, and the soil field capacity was higher than that of each monoculture system in each soil layer (except 20-40 cm soil layer) since the 5th year after planting. The intercropping system had continuous improvement on soil porosity in each soil layer, but mainly in the 0-20 and 20-40 cm soil layer, and the ratio of capillary porosity was also improved. The soil bulk density, field capacity and soil porosity obtained continuous improvement during the conversion of cropland to agroforestry system, and the improvement on soil physical properties was stronger in shallow soil layer than in deep soil.

  11. Soil fauna and its relation with environmental variables in soil management systems

    Directory of Open Access Journals (Sweden)

    Dilmar Baretta

    Full Text Available The present study aims to generate knowledge about the soil fauna, its relation to other explanatory environmental variables, and, besides it, to select edaphic indicators that more contribute to separate the land use systems (LUS. Five different LUS were chosen: conventional tillage with crop rotation (CTCR; no-tillage with crop rotation (NTCR; conventional tillage with crop succession (CTCS; no-tillage with crop succession (NTCS and minimum tillage with crop succession (MTCS. The samples were made in the counties Chapecó, Xanxerê and Ouro Verde located in the state of Santa Catarina, Brazil, and were considered the true replicates of the LUS. In each site, nine points were sampled in a sampling grid of 3 x 3. At the same points, soil was sampled for the physical, chemical and biological attributes (environmental variables. Pitfall traps were used to evaluate the soil fauna. Data were analyzed using principal component analysis (PCA and canonical discriminant analysis (CDA. The soil fauna presented potential to be used as indictors of soil quality, since some groups proved to be sensible to changes of the environmental variables and to soil management and tillage. The soil management using crop rotation (NTCR and CTCR presented higher diversity, compared to the systems using crop succession (NTCS, MTCS and NTCS, evidencing the importance of the soil tillage, independent of the season (summer or winter. The variable that better contributed to explain these changes were the chemical variables (potassium, pH, calcium, organic matter, available phosphorus, potential acidity, and biological variables (Shannon diversity index, Collembola, Pielou equitability index and microbial biomass carbon, respectively.

  12. A noncontact laser system for measuring soil surface topography

    International Nuclear Information System (INIS)

    Huang, C.; White, I.; Thwaite, E.G.; Bendeli, A.

    1988-01-01

    Soil surface topography profoundly influences runoff hydrodynamics, soil erosion, and surface retention of water. Here we describe an optical noncontact system for measuring soil surface topography. Soil elevation is measured by projecting a laser beam onto the surface and detecting the position of the interception point. The optical axis of the detection system is oriented at a small angle to the incident beam. A low-power HeNe (Helium-Neon) laser is used as the laser source, a photodiode array is used as the laser image detector and an ordinary 35-mm single lens reflex camera provides the optical system to focus the laser image onto the diode array. A wide spectrum of measurement ranges (R) and resolutions are selectable, from 1 mm to 1 m. These are determined by the laser-camera distance and angle, the focal length of the lens, and the sensing length of the diode array and the number of elements (N) contained in the array. The resolution of the system is approximately R/2N. We show for the system used here that this resolution is approximately 0.2%. In the configuration selected, elevation changes of 0.16 mm could be detected over a surface elevation range of 87 mm. The sampling rate of the system is 1000 Hz, which permits soil surfaces to be measured at speeds of up to 1 m s −1 with measurements taken at 1-mm spacing. Measurements of individual raindrop impacts on the soil and of soil surfaces before and after rain show the versatility of the laser surface profiler, which has applications in studies of erosion processes, surface storage and soil trafficability

  13. Polarimetry Microlensing of Close-in Planetary Systems

    International Nuclear Information System (INIS)

    Sajadian, Sedighe; Hundertmark, Markus

    2017-01-01

    A close-in giant planetary (CGP) system has a net polarization signal whose value varies depending on the orbital phase of the planet. This polarization signal is either caused by the stellar occultation or by reflected starlight from the surface of the orbiting planet. When the CGP system is located in the Galactic bulge, its polarization signal becomes too weak to be measured directly. One method for detecting and characterizing these weak polarization signatures due to distant CGP systems is gravitational microlensing. In this work, we focus on potential polarimetric observations of highly magnified microlensing events of CGP systems. When the lens is passing directly in front of the source star with its planetary companion, the polarimetric signature caused by the transiting planet is magnified. As a result, some distinct features in the polarimetry and light curves are produced. In the same way, microlensing amplifies the reflection-induced polarization signal. While the planet-induced perturbations are magnified whenever these polarimetric or photometric deviations vanish for a moment, the corresponding magnification factor of the polarization component(s) is related to the planet itself. Finding these exact times in the planet-induced perturbations helps us to characterize the planet. In order to evaluate the observability of such systems through polarimetric or photometric observations of high-magnification microlensing events, we simulate these events by considering confirmed CGP systems as their source stars and conclude that the efficiency for detecting the planet-induced signal with the state-of-the-art polarimetric instrument (FORS2/VLT) is less than 0.1%. Consequently, these planet-induced polarimetry perturbations can likely be detected under favorable conditions by the high-resolution and short-cadence polarimeters of the next generation.

  14. Polarimetry Microlensing of Close-in Planetary Systems

    Energy Technology Data Exchange (ETDEWEB)

    Sajadian, Sedighe [Department of Physics, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Hundertmark, Markus, E-mail: s.sajadian@cc.iut.ac.ir [Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg (ZAH), D-69120 Heidelberg (Germany)

    2017-04-01

    A close-in giant planetary (CGP) system has a net polarization signal whose value varies depending on the orbital phase of the planet. This polarization signal is either caused by the stellar occultation or by reflected starlight from the surface of the orbiting planet. When the CGP system is located in the Galactic bulge, its polarization signal becomes too weak to be measured directly. One method for detecting and characterizing these weak polarization signatures due to distant CGP systems is gravitational microlensing. In this work, we focus on potential polarimetric observations of highly magnified microlensing events of CGP systems. When the lens is passing directly in front of the source star with its planetary companion, the polarimetric signature caused by the transiting planet is magnified. As a result, some distinct features in the polarimetry and light curves are produced. In the same way, microlensing amplifies the reflection-induced polarization signal. While the planet-induced perturbations are magnified whenever these polarimetric or photometric deviations vanish for a moment, the corresponding magnification factor of the polarization component(s) is related to the planet itself. Finding these exact times in the planet-induced perturbations helps us to characterize the planet. In order to evaluate the observability of such systems through polarimetric or photometric observations of high-magnification microlensing events, we simulate these events by considering confirmed CGP systems as their source stars and conclude that the efficiency for detecting the planet-induced signal with the state-of-the-art polarimetric instrument (FORS2/VLT) is less than 0.1%. Consequently, these planet-induced polarimetry perturbations can likely be detected under favorable conditions by the high-resolution and short-cadence polarimeters of the next generation.

  15. Soil environmental quality in greenhouse vegetable production systems in eastern China: Current status and management strategies.

    Science.gov (United States)

    Hu, Wenyou; Zhang, Yanxia; Huang, Biao; Teng, Ying

    2017-03-01

    Greenhouse vegetable production (GVP) has become an important source of public vegetable consumption and farmers' income in China. However, various pollutants can be accumulated in GVP soils due to the high cropping index, large agricultural input, and closed environment. Ecological toxicity caused by excessive pollutants' accumulation can then lead to serious health risks. This paper was aimed to systematically review the current status of soil environmental quality, analyze their impact factors, and consequently to propose integrated management strategies for GVP systems. Results indicated a decrease in soil pH, soil salinization, and nutrients imbalance in GVP soils. Fungicides, remaining nutrients, antibiotics, heavy metals, and phthalate esters were main pollutants accumulating in GVP soils comparing to surrounding open field soils. Degradation of soil ecological function, accumulation of major pollutants in vegetables, deterioration of neighboring water bodies, and potential human health risks has occurred due to the changes of soil properties and accumulation of pollutants such as heavy metals and fungicides in soils. Four dominant factors were identified leading to the above-mentioned issues including heavy application of agricultural inputs, outmoded planting styles with poor environmental protection awareness, old-fashion regulations, unreasonable standards, and ineffective supervisory management. To guarantee a sustainable GVP development, several strategies were suggested to protect and improve soil environmental quality. Implementation of various strategies not only requires the concerted efforts among different stakeholders, but also the whole lifecycle assessment throughout the GVP processes as well as effective enforcement of policies, laws, and regulations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Novel chelating agents for iron, manganese, zinc, and copper mixed fertilisation in high pH soil-less cultures.

    Science.gov (United States)

    López-Rayo, Sandra; Nadal, Paloma; Lucena, Juan J

    2016-03-15

    Studies about simultaneous fertilisation with several micronutrients have increased in recent years, as Fe, Mn and Zn deficiencies may appear in the same culture conditions. In fertigation, the replacement of sulfates by synthetic chelates is essential in areas with high pH irrigation water and substrates. Ethylenediamine-N-(2-hydroxyphenylacetic acid)-N'-(4-hydroxyphenylacetic acid) (o,p-EDDHA) and ethylenediamine disuccinic acid (EDDS) are novel chelating agents whose efficacy in simultaneous fertilisation of Zn, Mn and Cu is unknown. This work evaluates the effectiveness of both ligands compared to traditional ligands (EDTA, HEEDTA and DTPA) applied as micronutrient chelate mixtures to soybean and navy bean plants grown in soil-less cultures at high pH by analysing the SPAD and micronutrient nutritional status, including the Composition Nutritional Diagnosis (CND) analysis tool. The application of micronutrients using o,p-EDDHA was more effective in providing Mn and Zn than traditional ligands or sulfates. The application using EDDS increased the Zn nutrition. The results are well correlated with the chemical stability of the formulations. The combined application of Mn and Zn as o,p-EDDHA chelates can represent a more effective source than traditional chelates in micronutrient fertiliser mixtures in soil-less cultures at a high pH. © 2015 Society of Chemical Industry.

  17. Metal bioaccumulation and mutagenesis in a Tradescantia clone following long-term exposure to soils from urban industrial areas and closed landfills.

    Science.gov (United States)

    Čėsnienė, Tatjana; Kleizaitė, Violeta; Bondzinskaitė, Skaistė; Taraškevičius, Ričardas; Žvingila, Donatas; Šiukšta, Raimondas; Rančelis, Vytautas

    2017-11-01

    Soil mutagens, particularly metals, may persist long after the source of pollution has been removed, representing a hazard to plants, animals, and humans in or near contaminated areas. Often, due to urban growth, previous land uses may be forgotten and hazards overlooked. We exposed Tradescantia clone #4430 plants to soil from two industrial areas (with different former uses) and two urban waste landfills in the city of Vilnius, all of which were long disused. Two modes of exposure were used: long-term exposure of growing plants in test soils for 0.5 or 1.0y, and short-term exposure of cuttings to water and dimethyl sulfoxide (DMSO) soil extracts. An increased frequency of micronuclei (MN) was observed with both modes of exposure. The concentrations of 24 metals and other elements were analyzed in the test soils and in above-ground plant parts, under both exposure modes, and the concentration coefficients (Cc) for various elements, the total contamination index (Zs) for soils and plants, and the bioaccumulation factor (BAF) for plants were calculated. These measurements allow a comparison of the contamination levels of soils and plants with equalized values. Metal accumulation levels in plants and soils showed significant differences, providing a better understanding of the genotoxicity of soils from closed landfills and highlighting the need to determine the concentrations of metals and other genotoxicants in plants in relation to genotoxicity. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Venezuelan Soils Bibliography with AGRIS System

    International Nuclear Information System (INIS)

    Brito, Julia; Marquez, Orfila; Ramos V, Dilia; Graterol, Orlando; Rivero, Aida

    1997-01-01

    The adoption of the AGRIS system to develop the soils bibliographical database, implies: 1) To adopt a bibliographical information system, specially designed for the agricultural area. 2) To use with precision the methodological rules and the computer platform offered by the system. 3) The possibility to be flowingly inserted in the bigger agricultural information network of in the Hispanic World. 4) The interinstitucional cooperation for the gathering and exchange of the Venezuelan documental information, related to the soils area. 5) To contribute to the enrichment of the documental information contained in the Venezuelan Agricultural Bibliographic Database, managered by the AGRIS/CARIS National Center, CENIAP headquarters (considered as the main agricultural investigation center, with a higher trajectory in the FONAIAP). The document briefly presents: the AGRIS (Agricultural Information System), the projects AGRIS/CARIS and VARIBEV (Valuation of Venezuelan Edaphology Bibliographic Information Files), the tematic contain characteristics and other bibliometric elements, the searching aided process, and the development of an agricultural vocabulary (AGROVOC), that became a Dictionary. Finally, the labor of the Venezuelan Edaphologists is recognized for the maintenance of the Venezuelan Edaphologic Bibliography, specialized in soils and related areas [es

  19. Soil settlement analysis in soft soil by using preloading system and prefabricated vertical draining runway of Kualanamu Airport

    Science.gov (United States)

    Roesyanto; Iskandar, R.; Silalahi, S. A.; Fadliansyah

    2018-02-01

    The method of soil improvement, using the combination of prefabricated vertical drain (PVD) and preloading, was used to accelerate the process of consolidation and the consolidation settlement in the runway of Kualanamu International Airport, which was constructed on the soft soil sediment like silty clay. In this research, the investigated area was the runway of Kualanamu International Airport zone I which had 11 meter-thickness of soft soil. Geotechnic instruments surveyed was settlement plate. Monitoring was done toward the behavior of landfill such as basic soil settlement. The result were compared with the analysis of finite element method of full scale in Mohr-Coulomb model by verifying the vertical drain of asymmetric unit cell and equivalent plane strain unit cell condition. The results of the research showed that there were an interesting behavior between the data in field observation and finite element of Mohr-Coulomb model. It was also found that the result of soil settlement of finite element method of Mohr-Coulomb model was closed to the result of settlement plate monitoring.

  20. Closed loop two-echelon repairable item systems

    NARCIS (Netherlands)

    Spanjers, L.; van Ommeren, Jan C.W.; Zijm, Willem H.M.

    In this paper we consider closed loop two-echelon repairable item systems with repair facilities both at a number of local service centers (called bases) and at a central location (the depot). The goal of the system is to maintain a number of production facilities (one at each base) in optimal

  1. Closed-loop two-echelon repairable item systems

    NARCIS (Netherlands)

    Spanjers, L.; Zijm, Willem H.M.; van Ommeren, Jan C.W.

    2003-01-01

    In this paper we consider closed loop two-echelon repairable item systems with repair facilities both at a number of local service centers (called bases) and at a central location (the depot). The goal of the system is to maintain a number of production facilities (one at each base) in optimal

  2. Closed loop two-echelon repairable item systems

    NARCIS (Netherlands)

    Spanjers, L.; van Ommeren, Jan C.W.; Zijm, Willem H.M.; Liberopoulos, G.; Papadopoulos, C.T.; Tan, B.; MacGregor Smith, J.; Gershwin, S.B.

    2006-01-01

    In this paper we consider closed loop two-echelon epairable item systems with repair facilities both at a number of local service centers (called bases) and at a central location (the depot). The goal of the system is to maintain a number of production facilities (one at each base) in optimal

  3. Anatomy of the underground system in Vernonia grandiflora Less. and V. brevifolia Less. (Asteraceae

    Directory of Open Access Journals (Sweden)

    Adriana Hissae Hayashi

    2007-11-01

    Full Text Available This work dealt with the anatomy of the underground system in Vernonia grandiflora Less. and V. brevifolia Less. (Vernonieae; Asteraceae, two perennial geophytes, to elucidate their ability to sprout in the Brazilian Cerrado conditions. V. grandiflora, a subshrubby species, possessed a thickened underground system constituted by a xylopodium and many tuberous roots. The xylopodium had stem and root structure and its buds were axillary or originated from the cortical parenchyma proliferation. The tuberous roots produced by this organ were adventitious and accumulated inulin-type fructans mainly in the cortical parenchyma. The thickened underground system of V. brevifolia, an herbaceous species, was a tuberous primary root whose buds originated from the proliferated pericycle. The occurrence of these bud-forming underground systems, which stored reserve compounds, enabled these plants to survive throughout unfavourable environmental conditions in the Cerrado, such as dry season and frequent fires in the winter.Este trabalho teve como objetivo estudar a anatomia dos sistemas subterrâneos de Vernonia grandiflora Less. e V. brevifolia Less. (Vernonieae; Asteraceae, duas geófitas perenes, a fim de esclarecer sua capacidade para brotar em condições de Cerrado. O sistema subterrâneo espessado de V. grandiflora, uma espécie subarbustiva, é constituído pelo xilopódio e por várias raízes tuberosas. O xilopódio possui estrutura mista (radicular e caulinar e suas gemas são de origem axilar ou se originam a partir da proliferação do parênquima cortical. As raízes tuberosas produzidas por este órgão são adventícias e acumulam frutanos do tipo inulina, principalmente no parênquima cortical. Em V. brevifolia, uma espécie herbácea, o sistema subterrâneo espessado é constituído pela raiz primária cujas gemas são originadas a partir do periciclo proliferado. A ocorrência destes sistemas subterrâneos gemíferos, que armazenam compostos

  4. Partitioning of hydrophobic pesticides within a soil-water-anionic surfactant system.

    Science.gov (United States)

    Wang, Peng; Keller, Arturo A

    2009-02-01

    Surfactants can be added to pesticide-contaminated soils to enhance the treatment efficiency of soil washing. Our results showed that pesticide (atrazine and diuron) partitioning and desorbability within a soil-water-anionic surfactant system is soil particle-size dependent and is significantly influenced by the presence of anionic surfactant. Anionic surfactant (linear alkylbenzene sulphonate, LAS) sorption was influenced by its complexation with both the soluble and exchangeable divalent cations in soils (e.g. Ca2+, Mg2+). In this study, we propose a new concept: soil system hardness which defines the total amount of soluble and exchangeable divalent cations associated with a soil. Our results showed that anionic surfactant works better with soils having lower soil system hardness. It was also found that the hydrophobic organic compounds (HOCs) sorbed onto the LAS-divalent cation precipitate, resulting in a significant decrease in the aqueous concentration of HOC. Our results showed that the effect of exchangeable cations and sorption of HOC onto the surfactant precipitates needs to be considered to accurately predict HOC behavior within soil-water-anionic surfactant systems.

  5. Water erosion during a 17-year period under two crop rotations in four soil management systems on a Southbrazilian Inceptisol

    Science.gov (United States)

    Bertol, Ildegardis; Vidal Vázquez, Eva; Paz Ferreiro, Jorge

    2010-05-01

    Soil erosion still remains a persistent issue in the world, and this in spite of the efforts to ameliorate soil management systems taken into account the point of view of environmental protection against soil losses. In South Brazil water erosion is mainly associated to rainfall events with a great volume and high intensity, which are more or less evenly distributed all over the year. Nowadays, direct drilling is the most widely soil management system used for the main crops of the region. However, some crops still are grown on conventionally tilled soils, which means mainly ploughing and harrowing and less frequently chisel ploughing. In Lages-Santa Catarina State, Brazil, a plot experiment under natural rain was started in 1992 on an Inceptisol with the aim of quantifying soil and water losses. Treatments included bare and vegetated plots. The crop succession was: oats (Avena strigosa), soybean (Glycine max), vetch (Vicia sativa), maize (Zea mays), fodder radish (Raphanus sativus) and beans (Phaseolus vulgaris). Soil tillage systems investigated in this study were: i) conventional tillage (CT), ii) reduced tillage (MT), iii) no tillage (NT) under crop rotation and iv) conventional tillage on bare soil (BS). Treatments CT and BS involved ploughing plus twice harrowing, whereas MT involved chisel ploughing plus harrowing. Rainfall erosivity from January 1 1992 to December 31 2009 was calculated. Soil losses from the BS treatment along the 17 year study period were higher than 1200 Mg ha-1. Crop cover significantly reduced erosion, so that under some crops soil losses in the CT treatment were 80% lower than in the BS treatment. In turn soil losses in the MT treatment, where tillage was performed by chiselling and harrowing, were on average about 50% lower than in the CT treatment. No tillage was the most efficient soil management system in reducing soil erosion, so that soil losses in the NT treatment were about 98% lower than in the BS treatment. The three

  6. Soil Water and Temperature System (SWATS) Instrument Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Cook, David R. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-04-01

    The soil water and temperature system (SWATS) provides vertical profiles of soil temperature, soil-water potential, and soil moisture as a function of depth below the ground surface at hourly intervals. The temperature profiles are measured directly by in situ sensors at the Central Facility and many of the extended facilities of the U.S. Department of Energy (DOE)’s Atmospheric Radiation Measurement (ARM) Climate Research Facility Southern Great Plains (SGP) site. The soil-water potential and soil moisture profiles are derived from measurements of soil temperature rise in response to small inputs of heat. Atmospheric scientists use the data in climate models to determine boundary conditions and to estimate the surface energy flux. The data are also useful to hydrologists, soil scientists, and agricultural scientists for determining the state of the soil.

  7. Behavioral analysis of differential Hebbian learning in closed-loop systems

    DEFF Research Database (Denmark)

    Kulvicius, Tomas; Kolodziejski, Christoph; Tamosiunaite, Minija

    2010-01-01

    Understanding closed loop behavioral systems is a non-trivial problem, especially when they change during learning. Descriptions of closed loop systems in terms of information theory date back to the 1950s, however, there have been only a few attempts which take into account learning, mostly...... measuring information of inputs. In this study we analyze a specific type of closed loop system by looking at the input as well as the output space. For this, we investigate simulated agents that perform differential Hebbian learning (STDP). In the first part we show that analytical solutions can be found...

  8. Soil heterogeneity and soil fertility gradients in smallholder agricultural systems of the east african highlands

    NARCIS (Netherlands)

    Tittonell, P.A.; Muriuki, A.; Klapwijk, C.J.; Shepherd, K.D.; Coe, R.; Vanlauwe, B.

    2013-01-01

    Heterogeneity in soil fertility in these smallholder systems is caused by both inherent soil-landscape and human-induced variability across farms differing in resources and practices. Interventions to address the problem of poor soil fertility in Africa must be designed to target such diversity and

  9. NOAA Soil Moisture Products System (SMOPS) Daily Blended Products

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Soil Moisture Operational Products System (SMOPS) combines soil moisture retrievals from multiple satellite sensors to provide a global soil moisture map with...

  10. Review article: closed-loop systems in anesthesia: is there a potential for closed-loop fluid management and hemodynamic optimization?

    Science.gov (United States)

    Rinehart, Joseph; Liu, Ngai; Alexander, Brenton; Cannesson, Maxime

    2012-01-01

    Closed-loop (automated) controllers are encountered in all aspects of modern life in applications ranging from air-conditioning to spaceflight. Although these systems are virtually ubiquitous, they are infrequently used in anesthesiology because of the complexity of physiologic systems and the difficulty in obtaining reliable and valid feedback data from the patient. Despite these challenges, closed-loop systems are being increasingly studied and improved for medical use. Two recent developments have made fluid administration a candidate for closed-loop control. First, the further description and development of dynamic predictors of fluid responsiveness provides a strong parameter for use as a control variable to guide fluid administration. Second, rapid advances in noninvasive monitoring of cardiac output and other hemodynamic variables make goal-directed therapy applicable for a wide range of patients in a variety of clinical care settings. In this article, we review the history of closed-loop controllers in clinical care, discuss the current understanding and limitations of the dynamic predictors of fluid responsiveness, and examine how these variables might be incorporated into a closed-loop fluid administration system.

  11. A Method for Precision Closed-Loop Irrigation Using a Modified PID Control Algorithm

    Science.gov (United States)

    Goodchild, Martin; Kühn, Karl; Jenkins, Malcolm; Burek, Kazimierz; Dutton, Andrew

    2016-04-01

    The benefits of closed-loop irrigation control have been demonstrated in grower trials which show the potential for improved crop yields and resource usage. Managing water use by controlling irrigation in response to soil moisture changes to meet crop water demands is a popular approach but requires knowledge of closed-loop control practice. In theory, to obtain precise closed-loop control of a system it is necessary to characterise every component in the control loop to derive the appropriate controller parameters, i.e. proportional, integral & derivative (PID) parameters in a classic PID controller. In practice this is often difficult to achieve. Empirical methods are employed to estimate the PID parameters by observing how the system performs under open-loop conditions. In this paper we present a modified PID controller, with a constrained integral function, that delivers excellent regulation of soil moisture by supplying the appropriate amount of water to meet the needs of the plant during the diurnal cycle. Furthermore, the modified PID controller responds quickly to changes in environmental conditions, including rainfall events which can result in: controller windup, under-watering and plant stress conditions. The experimental work successfully demonstrates the functionality of a constrained integral PID controller that delivers robust and precise irrigation control. Coir substrate strawberry growing trial data is also presented illustrating soil moisture control and the ability to match water deliver to solar radiation.

  12. Kasza: design of a closed water system for the greenhouse horticulture.

    Science.gov (United States)

    van der Velde, Raphaël T; Voogt, Wim; Pickhardt, Pieter W

    2008-01-01

    The need for a closed and sustainable water system in greenhouse areas is stimulated by the implementation in the Netherlands of the European Framework Directive. The Dutch national project Kasza: Design of a Closed Water System for the Greenhouse Horticulture will provide information how the water system in a greenhouse horticulture area can be closed. In this paper the conceptual design of two systems to close the water cycle in a greenhouse area is described. The first system with reverse osmosis system can be used in areas where desalination is required in order to be able to use the recycle water for irrigation of all crops. The second system with advanced oxidation using UV and peroxide can be applied in areas with more salt tolerant crops and good (low sodium) water sources for irrigation. Both systems are financially feasible in new greenhouse areas with substantial available recycle water. (c) IWA Publishing 2008.

  13. CLOSYS: Closed System for Water and Nutrient Management in Horticulture

    NARCIS (Netherlands)

    Marcelis, L.F.M.; Dieleman, J.A.; Boulard, T.; Garate, A.; Kittas, C.; Buschmann, C.; Brajeul, E.; Wieringa, G.; Groot, de F.; Loon, van A.; Kocsanyi, L.

    2006-01-01

    The EU project CLOSYS aimed at developing a CLOsed SYStem for water and nutrients in horticulture. The main objective was to control water and nutrients accurately such that pollution is minimized and crop quality enhanced. The closed system as developed in this project consists of crop growth

  14. Developing SASSA: a Soil Analysis Support System for Archaeologists

    Directory of Open Access Journals (Sweden)

    Clare Wilson

    2008-12-01

    Full Text Available There is constant pressure on field archaeologists to be familiar with the core concepts of a diverse range of specialist disciplines. Soils and sediments are an integral part of archaeological sites, and soil and sedimentary analyses applied to archaeological questions are now recognised as an important branch of geoarchaeology. However, the teaching of soils in archaeology degrees is variable and many archaeologists complain they lack the confidence and skills to describe and interpret properly the deposits they excavate. SASSA (Soil Analysis Support System for Archaeologists is a free-to-use, internet-based system designed to familiarise archaeologists with the concepts and possibilities offered by the scientific study of soils and sediments associated with archaeological sites. The aims of SASSA are: ◦To provide soils training specifically for archaeologists, suitable for either a university or workplace setting. ◦To provide a freely accessible soils and archaeology knowledge base for archaeologists working in either the office or the field. ◦To support archaeologists describing and interpreting soils in the field. ◦To enhance understanding of the types of archaeological questions that soil analysis can help to address. ◦To initiate dialogue between archaeologists, geoarchaeologists, and soil scientists in order to encourage the thoughtful application of soil analyses to archaeological questions. SASSA consists of two core components: a knowledge base and a field tool. The 'front-end' of the website is the knowledge base; this uses wiki technology to allow users to add their own content and encourage dialogue between archaeologists and geoarchaeologists. The field tool uses an XML data structure and decision-tree support system to guide the user through the process of describing and interpreting soils and sediments. SASSA is designed for use on both 'static' (PC and 'mobile' (PDA and laptop hardware in order to provide in situ

  15. Closed-loop System Identification with New Sensors

    DEFF Research Database (Denmark)

    Bendtsen, Jan Dimon; Trangbæk, K; Stoustrup, Jakob

    2008-01-01

    This paper deals with system identification of new system dynamics revealed by online introduction of new sensors in existing multi-variable linear control systems. The so-called "Hansen Scheme" utilises the dual Youla-Kucera parameterisation of all systems stabilised by a given linear controller...... to transform closed-loop system identification problems into open-loop-like problems. We show that this scheme can be formally extended to accomodate extra sensors in a nice way. The approach is illustrated on a simple simulation example....

  16. Soil Thermal Balance Analysis for a Ground Source Heat Pump System in a Hot-Summer and Cold-Winter Region

    Directory of Open Access Journals (Sweden)

    Zhongchao Zhao

    2018-05-01

    Full Text Available As a renewable and high energy efficiency technology providing air conditioning and domestic hot water, the ground source heat pump system (GSHPS has been extensively used worldwide in recent years. Compared with conventional systems, GSHPSs with heat recovery reject less heat into the soil and extract more heat from it, which can help reduce soil thermal imbalance in hot-summer and cold-winter regions. In this paper, conventional GSHPS, and GSHPS with different heat recovery ratios, in a typical city were compared based on thermal imbalance ratios, average soil temperatures and soil temperature increases. The transient system simulation software was used to simulate the operation performance of GSHPS. The thermal imbalance ratio and soil temperature decreased with increasing heat recovery ratio. After 20 years of operation, the soil thermal imbalance ratios of the GSHPS were 29.2%, 21.1%, 16%, and 5.2%, and the soil temperature rises were 8.78 °C, 5.25 °C, 3.44 °C, and 0.34 °C, while the heat recovery ratios were 0, 18%, 30% and 53%, respectively. Consequently, a GSHPS with heat recovery is a potentially efficient and economical approach for buildings in hot-summer and cold-winter regions.

  17. Influence of Soil Tillage Systems on Soil Respiration and Production on Wheat, Maize and Soybean Crop

    Science.gov (United States)

    Moraru, P. I.; Rusu, T.

    2012-04-01

    Soil respiration leads to CO2 emissions from soil to the atmosphere, in significant amounts for the global carbon cycle. Soil capacity to produce CO2 varies depending on soil, season, intensity and quality of agrotechnical tillage, soil water, cultivated plant, fertilizer etc. The data presented in this paper were obtained on argic-stagnic Faeoziom (SRTS, 2003). These areas were was our research, presents a medium multiannual temperature of 8.20C, medium of multiannual rain drowns: 613 mm. The experimental variants chosen were: A. Conventional system (CS): V1-reversible plough (22-25 cm)+rotary grape (8-10 cm); B. Minimum tillage system (MT): V2 - paraplow (18-22 cm) + rotary grape (8-10 cm); V3 - chisel (18-22 cm) + rotary grape (8-10 cm);V4 - rotary grape (10-12 cm); C. No-Tillage systems (NT): V5 - direct sowing. The experimental design was a split-plot design with three replications. In one variant the area of a plot was 300 m2. The experimental variants were studied in the 3 years crop rotation: maize - soy-bean - autumn wheat. To soil respiration under different tillage practices, determinations were made for each crop in four vegetative stages (spring, 5-6 leaves, bean forming, harvest) using ACE Automated Soil CO2 Exchange System. Soil respiration varies throughout the year for all three crops of rotation, with a maximum in late spring (1383 to 2480 mmoli m-2s-1) and another in fall (2141 to 2350 mmoli m-2s-1). The determinations confirm the effect of soil tillage system on soil respiration, the daily average is lower at NT (315-1914 mmoli m-2s-1), followed by MT (318-2395 mmoli m-2s-1) and is higher in the CS (321-2480 mmol m-2s-1). Productions obtained at MT and NT don't have significant differences at wheat and are higher at soybean. The differences in crop yields are recorded at maize and can be a direct consequence of loosening, mineralization and intensive mobilization of soil fertility. Acknowledgments: This work was supported by CNCSIS

  18. Lasting effects of soil health improvements with management changes in cotton-based cropping systems in a sandy soil

    Science.gov (United States)

    The soil microbial component is essential for sustainable agricultural systems and soil health. This study evaluated the lasting impacts of 5 years of soil health improvements from alternative cropping systems compared to intensively tilled continuous cotton (Cont. Ctn) in a low organic matter sandy...

  19. Integrated universal soil loss equation (USLE and Geographical Information System (GIS for soil erosion estimation in A Sap basin: Central Vietnam

    Directory of Open Access Journals (Sweden)

    Tung Gia Pham

    2018-06-01

    Full Text Available Central Vietnam is very susceptible to soil erosion due to its complicated terrain and heavy rainfall. The objective of this study was to quantify soil erosion in the A Sap river basin, A Luoi district, Thua Thien Hue Province, Vietnam, using the Universal Soil Loss Equation (USLE and Geographical Information System (GIS. The results showed that 34% of land area lost accumulated to 10 t ha−1 year−1 while 47% of the total area lost less than 1 t ha−1 year−1. Natural forest land lost the most with an average of about 19 t ha−1 year−1, followed by plantation forest with approximately 7 t ha−1 year−1 and other agricultural lands at 3.70 and 1.45 t ha−1 year−1 for yearly crops and paddy rice, respectively. Soil erosion was most sensitive to the topographic factor (LS, followed by the practice support factor (P, soil erodibility factor (K, cropping management (C, and the rainfall erosivity factor (R. Implications are that changes to the cultivated calendar and implementing intercropping are effective ways to prevent soil erosion in cultivated lands. Furthermore, introducing broad leaves trees for mountainous areas in A Sap basin was the most effective practice in reducing soil erosion. The study also pointed out that the combination of available data sources used with the USLE and GIS technology is a viable option to calculate soil erosion in Central Vietnam, which would allow targeted attention toward a solution is to reduce future soil erosion. Keywords: Central Vietnam, GIS, Soil erosion, USLE

  20. Tillage System and Cover Crop Effects on Soil Quality

    DEFF Research Database (Denmark)

    Abdollahi, Lotfollah; Munkholm, Lars Juhl

    2014-01-01

    ), and moldboard plowing (MP) with and without a cover crop were evaluated in a long-term experiment on a sandy loam soil in Denmark. Chemical, physical, and biological soil properties were measured in the spring of 2012. The field measurements included mean weight diameter (MWD) after the drop-shatter test......, penetration resistance, and visual evaluation of soil structure (VESS). In the laboratory, aggregate strength, water-stable aggregates (WSA), and clay dispersibility were measured. The analyzed chemical and biological properties included soil organic C (SOC), total N, microbial biomass C, labile P and K......Optimal use of management systems including tillage and winter cover crops is recommended to improve soil quality and sustain agricultural production. The effects on soil properties of three tillage systems (as main plot) including direct drilling (D), harrowing to a depth of 8 to 10 cm (H...

  1. Closed-Loop and Robust Control of Quantum Systems

    Directory of Open Access Journals (Sweden)

    Chunlin Chen

    2013-01-01

    Full Text Available For most practical quantum control systems, it is important and difficult to attain robustness and reliability due to unavoidable uncertainties in the system dynamics or models. Three kinds of typical approaches (e.g., closed-loop learning control, feedback control, and robust control have been proved to be effective to solve these problems. This work presents a self-contained survey on the closed-loop and robust control of quantum systems, as well as a brief introduction to a selection of basic theories and methods in this research area, to provide interested readers with a general idea for further studies. In the area of closed-loop learning control of quantum systems, we survey and introduce such learning control methods as gradient-based methods, genetic algorithms (GA, and reinforcement learning (RL methods from a unified point of view of exploring the quantum control landscapes. For the feedback control approach, the paper surveys three control strategies including Lyapunov control, measurement-based control, and coherent-feedback control. Then such topics in the field of quantum robust control as H∞ control, sliding mode control, quantum risk-sensitive control, and quantum ensemble control are reviewed. The paper concludes with a perspective of future research directions that are likely to attract more attention.

  2. Closed-loop and robust control of quantum systems.

    Science.gov (United States)

    Chen, Chunlin; Wang, Lin-Cheng; Wang, Yuanlong

    2013-01-01

    For most practical quantum control systems, it is important and difficult to attain robustness and reliability due to unavoidable uncertainties in the system dynamics or models. Three kinds of typical approaches (e.g., closed-loop learning control, feedback control, and robust control) have been proved to be effective to solve these problems. This work presents a self-contained survey on the closed-loop and robust control of quantum systems, as well as a brief introduction to a selection of basic theories and methods in this research area, to provide interested readers with a general idea for further studies. In the area of closed-loop learning control of quantum systems, we survey and introduce such learning control methods as gradient-based methods, genetic algorithms (GA), and reinforcement learning (RL) methods from a unified point of view of exploring the quantum control landscapes. For the feedback control approach, the paper surveys three control strategies including Lyapunov control, measurement-based control, and coherent-feedback control. Then such topics in the field of quantum robust control as H(∞) control, sliding mode control, quantum risk-sensitive control, and quantum ensemble control are reviewed. The paper concludes with a perspective of future research directions that are likely to attract more attention.

  3. Nutrient Release from Disturbance of Infiltration System Soils during Construction

    OpenAIRE

    Daniel P. Treese; Shirley E. Clark; Katherine H. Baker

    2012-01-01

    Subsurface infiltration and surface bioretention systems composed of engineered and/or native soils are preferred tools for stormwater management. However, the disturbance of native soils, especially during the process of adding amendments to improve infiltration rates and pollutant removal, may result in releases of nutrients in the early life of these systems. This project investigated the nutrient release from two soils, one disturbed and one undisturbed. The disturbed soil was collected i...

  4. Solar system for soil drainage

    International Nuclear Information System (INIS)

    Kocic, Z.R.; Stojanovic, J.B.; Antic, M.A.; Pavlovic, T.M.

    1999-01-01

    The paper reviews solar system for drainage of the cultivable agricultural surfaces which can be situated near the rivers in plains. These are usually very fertile surfaces which cannot be cultivated die to constant presence of the water. Using such solar systems should increase the percentage of cultivable surfaces. These systems can also be installed on the cultivable agricultural surfaces, where the water surfaces or so called still waters appear, which make impossible the application of agritechnical measures on these surfaces, significantly decreasing crops and creating conditions for the growth of pond plants and animals. Increasing the percentage of cultivable agricultural surfaces would increase national agricultural income. At the same time, increasing the percentage of cultivable agricultural surfaces decreases the surfaces of unhealthy bog, swamp and marshland soils, where many insect breed. They are the cause for soil spraying from the air, which causes the pollution of environment. Solar systems do not pollute the environment because they use solar energy as the purest source of energy. Their usage has special significance in the places where there is no electricity distribution network

  5. Bidirectional neural interface: Closed-loop feedback control for hybrid neural systems.

    Science.gov (United States)

    Chou, Zane; Lim, Jeffrey; Brown, Sophie; Keller, Melissa; Bugbee, Joseph; Broccard, Frédéric D; Khraiche, Massoud L; Silva, Gabriel A; Cauwenberghs, Gert

    2015-01-01

    Closed-loop neural prostheses enable bidirectional communication between the biological and artificial components of a hybrid system. However, a major challenge in this field is the limited understanding of how these components, the two separate neural networks, interact with each other. In this paper, we propose an in vitro model of a closed-loop system that allows for easy experimental testing and modification of both biological and artificial network parameters. The interface closes the system loop in real time by stimulating each network based on recorded activity of the other network, within preset parameters. As a proof of concept we demonstrate that the bidirectional interface is able to establish and control network properties, such as synchrony, in a hybrid system of two neural networks more significantly more effectively than the same system without the interface or with unidirectional alternatives. This success holds promise for the application of closed-loop systems in neural prostheses, brain-machine interfaces, and drug testing.

  6. Closed-cycle cooling systems for nuclear power plants

    International Nuclear Information System (INIS)

    Santini, Lorenzo

    2006-01-01

    The long experience in the field of closed-cycle cooling systems and high technological level of turbo machines and heat exchangers concurs to believe in the industrial realizability of nuclear systems of high thermodynamic efficiency and intrinsic safety [it

  7. USDA soil classification system dictates site surface management

    International Nuclear Information System (INIS)

    Bowmer, W.J.

    1985-01-01

    Success or failure of site surface management practices greatly affects long-term site stability. The US Department of Agriculture (USDA) soil classification system best documents those parameters which control the success of installed practices for managing both erosion and surface drainage. The USDA system concentrates on soil characteristics in the upper three meters of the surface that support the associated flora both physically and physiologically. The USDA soil survey first identifies soil series based on detailed characteristics that are related to production potential. Using the production potential, land use capability classes are developed. Capability classes reveal the highest and best agronomic use for the site. Lower number classes are considered arable while higher number classes are best suited for grazing agriculture. Application of ecological principles based on the USDA soil survey reveals the current state of the site relative to its ecological potential. To assure success, site management practices must be chosen that are compatible with both production capability and current state of the site

  8. A multichannel automated chamber system for continuous measurement of forest soil CO2 efflux

    International Nuclear Information System (INIS)

    Liang, N.; Inoue, G.; Fujinuma, Y.

    2003-01-01

    Development of a fast-response multi-chamber system for measuring soil-surface carbon dioxide efflux is described. The sixteen-chamber automated system continuously monitors surface carbon dioxide efflux at different locations within a forest ecosystem using a single infrared gas analyzer that successively measures gas samples from each of the sixteen chambers. The chambers have lids that open and close automatically, and are connected in parallel to the single carbon dioxide analyzer which is equipped with a sixteen-channel gas sampler. Air is withdrawn continuously from the inlets and outlets of each chamber and fed sequentially to the gas analyzer. Using this instrument, surface carbon dioxide efflux was measured in a 40-year old pine forest during a three-month period (February to May) in 2001. Results showed a steady increase in mean carbon dioxide efflux during the period. A statistically significant correlation between soil-surface carbon dioxide efflux and surface temperature was also established. Spatial variation of carbon dioxide efflux was found to be higher in the non-growing season than in the growing season. It was concluded that the multi-channel automated chamber system can provide large amounts of high quality data on soil carbon dioxide efflux over a large surface area and simultaneously evaluate both spatial and temporal variation. The system uses a relatively small amount of power (70 W maximum) which can be further reduced (to 15 W) by minimizing the pressure difference between inside and outside the chamber. The system requires no maintenance other than the calibration of the gas analyzer and measurement of the flow rate through the chambers. 34 refs., 8 figs

  9. Root-soil relationships and terroir

    Science.gov (United States)

    Tomasi, Diego

    2015-04-01

    Soil features, along with climate, are among the most important determinants of a succesful grape production in a certain area. Most of the studies, so far, investigated the above-ground vine response to differente edaphic and climate condition, but it is clearly not sufficient to explain the vine whole behaviour. In fact, roots represent an important part of the terroir system (soil-plant-atmosphere-man), and their study can provide better comprehension of vine responses to different environments. The root density and distribution, the ability of deep-rooting and regenerating new roots are good indicators of root well-being, and represents the basis for an efficient physiological activity of the root system. Root deepening and distribution are strongly dependent and sensitive on soil type and soil properties, while root density is affected mostly by canopy size, rootstock and water availability. According to root well-being, soil management strategies should alleviate soil impediments, improving aeration and microbial activity. Moreover, agronomic practices can impact root system performance and influence the above-ground growth. It is well known, for example, that the root system size is largely diminished by high planting densities. Close vine spacings stimulate a more effective utilization of the available soil, water and nutrients, but if the competition for available soil becomes too high, it can repress vine growth, and compromise vineyard longevity, productivity and reaction to growing season weather. Development of resilient rootstocks, more efficient in terms of water and nutrient uptake and capable of dealing with climate and soil extremes (drought, high salinity) are primary goals fore future research. The use of these rootstocks will benefit a more sustainable use of the soil resources and the preservation and valorisation of the terroir.

  10. Nitrogen dynamics in a soil-sugar cane system

    International Nuclear Information System (INIS)

    Oliveira, Julio Cesar Martins de; Reichardt, Klaus; Bacchi, Osny O.S.; Timm, Luis Carlos; Tominaga, Tania Toyomi; Castro Navarro, Roberta de; Cassaro, Fabio Augusto Meira; Dourado-Neto, Durval; Trivelin, Paulo Cesar Ocheuse; Piccolo, Marisa de Cassia

    2000-01-01

    Results of an organic matter management experiment of a sugar cane crop are reported for the first cropping year. Sugar cane was planted in October 1997, and labeled with a 15 N fertilizer pulse to study the fate of organic matter in the soil-plant system. A nitrogen balance is presented, partitioning the system in plant components (stalk, tip and straw), soil components (five soil organic matter fractions) and evaluating leaching losses. The 15 N label permitted to determine, at the end of the growing season, amounts of nitrogen derived from the fertilizer, present in the above mentioned compartments. (author)

  11. A system for measuring fluxes of trace gases to and from soil and vegetation with a chamber technique

    International Nuclear Information System (INIS)

    Johansson, Christer; Richter, Andreas; Backlin, Leif; Granat, Lennart

    1983-09-01

    A mobile system for measurements of gaseous fluxes of SO 2 NO x , O 3 and water vapour between the atmosphere and the vegetation soil system using a chamber technique is described. Equipment, instruments and instrumental sensitivities are listed. A gas-handling system including calibration procedures and information on the chamber construction is also presented. With this system it is possible to make measurements using a wide range of concentrations including subambient levels. The environment in the chamber can be kept very close to ambient conditions. The mechanisms regulating the flux can be studied. A limitation of this system is the problem of extrapolating the fluxes obtained to larger areas. (author)

  12. Soil management practices for sustainable crop production

    International Nuclear Information System (INIS)

    Abalos, E.B.

    2005-01-01

    In a sustainable system, the soil is viewed as a fragile and living medium that must be protected and nurtured to ensure its long-term productivity and stability. However, due to high demand for food brought about by high population as well as the decline in agricultural lands, the soil is being exploited beyond its limit thus, leading to poor or sick soils. Sound soil management practices in the Philippines is being reviewed. The technologies, including the advantages and disadvantages are hereby presented. This includes proper cropping systems, fertilizer program, soil erosion control and correcting soil acidity. Sound soil management practices which conserve organic matter for long-term sustainability includes addition of compost, maintaining soil cover, increasing aggregates stability, soil tilt and diversity of soil microbial life. A healthy soil is a key component to sustainability as a health soil produce healthy crop plants and have optimum vigor or less susceptible to pests. (author)

  13. Seaweeds in closed systems; Zeewieren in gesloten systemen

    Energy Technology Data Exchange (ETDEWEB)

    Hart, P. ' t [Koers en Vaart, Barendrecht (Netherlands); Schipper, J. [Hortimare, Heerhugowaard (Netherlands)

    2011-04-15

    the present prices for seaweed, the cultivation of mature plants in closed systems for industrial applications is not feasible. Even with fast-growing types and relatively expensive seaweeds, the investment costs of a closed cultivation system are too high. Palmaria Palmata can be commercially cultivated from basic material into mature plants for consumption using concrete tanks, but not using steel tanks. Ulva lactuca cannot be commercially cultivated for consumption purposes, whether in concrete tanks or steel tanks. In addition, consumer demand for Ulva lactuca in Europe is currently very small. Nurturing basic materials into young plants in steel tanks is feasible in economic, technical and social terms. The preference is for steel tanks with a tidal upweller system, which is very flexible and can also be used as a fully closed system. Young plants can also be nurtured in concrete tanks at sea. However, concrete tanks are more vulnerable and less flexible at sea compared to steel tanks. Young plants can also be nurtured in onshore tanks. In view of the great need for clean seawater, the problems in maintaining the right water temperature on land and the bigger risk of tank pollution, a closed offshore system is the preferred option. The use of offshore closed systems for propagating plant materials for large-scale cultivation appears to be an indispensable link in the chain. In view of the nature and scope of this feasibility study, not all questions can be answered in detail. However, the conclusion is that seaweed cultivation in offshore floating systems is viable in the Dutch situation. The nurturing of young plant material in closed systems may be an essential link in the large-scale offshore cultivation on lines and/or nets [Dutch] Zeewieren zijn een potentiele bron van groene grondstoffen. Ze worden gebruikt voor menselijke consumptie, bevatten specifieke bindmiddelen zoals alginaten en carragenen, en zijn toepasbaar als meststof met groeibevorderende

  14. Determination of solute organic concentration in contaminated soils using a chemical-equilibrium soil column system

    DEFF Research Database (Denmark)

    Gamst, Jesper; Kjeldsen, Peter; Christensen, Thomas Højlund

    2007-01-01

    using two soils with different content of organic carbon (f(oc) of 1.5 and 6.5%, respectively). A quadruple blind test of the ER-V system using glass beads in stead of soil showed an acceptable recovery (65-85%) of all of the 11 VOCs tested. Only for the most volatile compound (heptane, K-H similar...... to 80) an unacceptable recovery was found (9%). The contact time needed for obtaining chemical equilibrium was tested in the ER-H system by performing five test with different duration (1, 2, 4, 7 and 19 days) using the low organic carbon soil. Seven days of contact time appeared sufficient...... for determination of solute concentration in a contaminated soil were developed; (1) a chemical Equilibrium and Recirculation column test for Volatile organic chemicals (ER-V) and (2) a chemical Equilibrium and Recirculation column test for Hydrophobic organic chemicals (ER-H). The two test systems were evaluated...

  15. Soil contamination by heavy metals: measurements from a closed unlined landfill.

    Science.gov (United States)

    Kasassi, A; Rakimbei, P; Karagiannidis, A; Zabaniotou, A; Tsiouvaras, K; Nastis, A; Tzafeiropoulou, K

    2008-12-01

    The aim of the present study was the characterization of soil samples of a closed unlined landfill located northwest of Thessaloniki, North Greece, in relation to heavy metals values. Samples were obtained by drilling in different depths (2.5-17.5m). Then they were analyzed by atomic absorption spectrophotometry for Cd, Cr, Cu, Ni, Pb and Zn investigation. The chemical analysis showed that the metal values varied over a wide range: from 0.50 to 18.75mg/kg for Cd, 3.88-171.88mg/kg for Cr, 8.13-356.25mg/kg for Cu, 5.63-63.75mg/kg for Ni, 2.50-92.50mg/kg for Pb and 6.38-343.75mg/kg for Zn. The highest values found in three of the six drillings, in depths over 2.5m. Although the area is heavily industrialized, the presented results indicated that local industries have not constituted an extensive metal pollution source for the site. Finally, after all necessary preparatory operations of site cleaning and flattening, surface planting selected and applied as a phytoremediation rehabilitation method of the site.

  16. Behaviour of radioactive and stable isotopes of calcium in the soil-solution-plant system at different soil humidity

    International Nuclear Information System (INIS)

    Karavaeva, E.N.; Molchanova, I.V.

    1976-01-01

    The results of experiments performed to study the behaviour of radioactive and stable isotopes of Ca in soil - solution - plant system at different soil moistening are given. The experiments have been conducted in culture pans with two soils: soddy-meadow and soddy-podzolic differing in a number of physico-chemical properties. The solution of radioactive Ca( 45 CaCl 2 ) has been applied to soddy-meadow soil at the rate of 0.2 μcurie/kg, and to soddy-podzolic soil - at the rate of 0.1 μcurie/kg. The distribution and accumulation coefficients are estimated by the ratio to the total content of stable Ca and 45 Ca in soil. A direct relationship between distribution coefficients and the rate of soil moistening is observed. It has been established that 45 Ca and the natural stable isotopes of Ca applied to the soil differ in the type of distribution in soil - soil solution system and in accumulation by plants. However, a great similarity has been observed in behaviour of radioactive and stable isotopes of Ca depending on soil moistening

  17. Sorption of phenanthrene on agricultural soils

    DEFF Research Database (Denmark)

    Soares, Antonio; Møldrup, Per; Minh, Luong Nhat

    2013-01-01

    Polyaromatic hydrocarbon (PAH) sorption to soil is a key process deciding the transport and fate of PAH, and potential toxic impacts in the soil and groundwater ecosystems, for example in connection with atmospheric PAH deposition on soils. There are numerous studies on PAH sorption in relatively......, 0.25–1-m depth) by the single-point adsorption method. The organic carbon partition coefficient, KOC (liter per kilogram) for topsoils was found generally to fall between the KOC values estimated by the two most frequently used models for PAH partitioning, the Abdul et al. (Hazardous Waste...... & Hazardous Materials 4(3):211–222, 1987) model and Karickhoff et al. (Water Research 13:241–248, 1979) model. A less-recognized model by Karickhoff (Chemosphere 10:833–846, 1981), yielding a KOC of 14,918 L kg−1, closely corresponded to the average measured KOC value for the topsoils, and this model...

  18. Soil microbial biomass in an agroforestry system of Northeast Brazil

    Directory of Open Access Journals (Sweden)

    Rosane C. Rodrigues

    2015-01-01

    Full Text Available Agroforestry systems (AFS are considered alternative land use options to help prevent soil degradation and improve soil microbial biomass and organic C status. However, it is unclear how different densities of babassu palm [Attalea speciosa (syn. Orbignya phalerata], which is an important tree in Northeast Brazil, affect the soil microbial biomass. We investigated the soil microbial biomass C and activity under AFS with different densities of babassu palm associated with Brachiaria brizantha grass. Soil microbial biomass C (MBC, soil microbial biomass N (MBN, MBC:total organic C ratio, fluorescein diacetate hydrolysis and dehydrogenase activity showed highest values in plots with high density of babassu palm. On the other hand, the respiratory quotient (qCO2 was significantly greater in plots without babassu palm. Brachiaria brizantha in monoculture may promote C losses from the soil, but AFS with high density of babassu palm may increase the potential of soils to accumulate C.Keywords: Enzyme activity, tropical soil, babassu palm, silvopastoral system, soil quality.DOI: 10.17138/TGFT(341-48

  19. Virus movement in soil during saturated and unsaturated flow.

    Science.gov (United States)

    Lance, J C; Gerba, C P

    1984-02-01

    Virus movement in soil during saturated and unsaturated flow was compared by adding poliovirus to sewage water and applying the water at different rates to a 250-cm-long soil column equipped with ceramic samplers at different depths. Movement of viruses during unsaturated flow of sewage through soil columns was much less than during saturated flow. Viruses did not move below the 40-cm level when sewage water was applied at less than the maximum infiltration rate; virus penetration in columns flooded with sewage was at least 160 cm. Therefore, virus movement in soils irrigated with sewage should be less than in flooded groundwater recharge basins or in saturated soil columns. Management of land treatment systems to provide unsaturated flow through the soil should minimize the depth of virus penetration. Differences in virus movement during saturated and unsaturated flow must be considered in the development of any model used to simulate virus movement in soils.

  20. Acidity field of soils as ion-exchange systems and the diagnostics of genetic soil horizons

    Science.gov (United States)

    Kokotov, Yu. A.; Sukhacheva, E. Yu.; Aparin, B. F.

    2014-12-01

    For the comprehensive description of the acidity of a two-phase ion-exchange system, we should analyze two curves of the ionite titration by a strong base in water and salt solutions and find the quantitative relationships between the corresponding pH characteristics. An idea of the three-dimensional field of acidity of ion-exchange systems (the phase space of the soil acidity characteristics) and its three two-dimensional projections is suggested. For soils, three interrelated characteristics—the pH values of the salt and water extracts and the degree of base saturation—can serve as spatial coordinates for the acidity field. Representation of factual data in this field makes it possible to compare and analyze the acidity characteristics of different soils and soil horizons and to determine their specific features. Differentiation of the field into separate volumes allows one to present the data in a discrete form. We have studied the distribution patterns of the groups of soil horizons from Leningrad oblast and other regions of northwestern Russia in the acidity field. The studied samples are grouped in different partially overlapping areas of the projections of the acidity field. The results of this grouping attest to the correctness of the modern classification of Russian soils. A notion of the characteristic soil area in the acidity field is suggested; it can be applied to all the soils with a leaching soil water regime.

  1. National Soil Information System in Turkey

    Science.gov (United States)

    Emrah Erdogan, Hakki; Sahin, Mehmet; Sahin, Yuksel

    2013-04-01

    Land consolidation (LC) represents complexity if management, legal, economic and technical procedures realized in order to adjust the land structure according to actual human preferences and needs. It includes changes in ownership rights to land and other real estate property, exchange of parcels among owners, changes in parcel borders, parcel size and shape, joining and dividing of parcels, changes in land use, construction works as roads, bridges, water changes etc.. Since the subject of LC is agricultural lands, the quality of consolidation depends on the quality of soil data. General Directorate of Agrarian Reform (GDAR) is the responsible institution on land consolidation whole of Turkey. Under GDAR, National Soil Information System (NSIS) has been build up with base soil data in relevant scale (1:5000). NSIS contain detailed information on soil chemical and physical properties, current land use, parent material, land capability class, Storie Index Values. SI were used on land consolidation, land use planning and farm development services. LCC was used for land distribution, rental land; define of village settlement, consolidation, expropriation, reconstruction, reclamation, non-agricultural usage. LCC were also specified to subclasses in four different limited factors as i) flow and erosion risk ii) requirement of drainage and soil moisture iii) Limits of soil tillage and root (shallow soils, low water retention capacity, stony, salty .etc) iv) climatic limits. In this study, digital soil survey and mapping project located in Yumurtalik, Adana is presented as an example of NSIS data structure. The project cover an area of 45709 ha that include crop lands as an area of 28528 ha and other land use (urban, roads..etc) as an area of 17181 ha. Soil profiles were described in 45 different points and totally 1279 soil samples were collected in field study and the check bore hole were made in 3170 points.

  2. Soil threats and soil protection: the role of biotechnology

    International Nuclear Information System (INIS)

    Rubio, J. L.

    2009-01-01

    The concept of soil conservation/soil protection in its wider sense has undergone important changes through history. Perceptions of soil as a crucial base of life in ancient cultures progressively evolved to a more pragmatic vision, with close connection to food production for survival. For centuries, agrarian production and the provision of food for humankind remained the main and crucial vision of the interaction of societies with soil. However, there are also some other new and important concepts related to soil which have progressively developed. (Author)

  3. Understanding soil food web dynamics, how close do we get?

    NARCIS (Netherlands)

    Morriën, E.

    2016-01-01

    Soil food webs are traditionally considered to have distinct energy channels through which resources flow belowground. Resources enter the soil food web either from roots or from detrital inputs. Compared to this traditional view we are now much more aware of the flow of carbon, nitrogen and other

  4. The integration of innovative technologies into a physical-separation-based soil washing system

    International Nuclear Information System (INIS)

    Krstich, M.A.

    1995-01-01

    An innovative system's approach to the treatment of soils at the Fernald Environmental Management Project (FEMP) has been proposed to effectively and cost competitively treat a significant mass of soil. The use of an integrated soil treatment system to decontaminate FEMP soils is a unique application of the soil washing technology. Due to the unfavorable soil particle size distribution and the ubiquitous distribution of uranium among these particle size fractions, conventional soil washing processes commonly used on predominantly sandy soils alone may not achieve the desirable waste minimization level without the inclusion of innovative technologies. This objective of this paper is to briefly describe the physical separation and chemical extraction process commonly used in soil washing operation and to present the baseline soil washing approach used on FEMP soils. Noting the successful and not-so-successful processes within the soil washing operation at the FEMP, a proposed innovative system's approach to treating FEMP soils will be described. This system's approach will integrate a conventional soil washing operation with proposed innovative technologies

  5. Closed bioregenerative life support systems: Applicability to hot deserts

    Science.gov (United States)

    Polyakov, Yuriy S.; Musaev, Ibrahim; Polyakov, Sergey V.

    2010-09-01

    Water scarcity in hot deserts, which cover about one-fifth of the Earth's land area, along with rapid expansion of hot deserts into arable lands is one of the key global environmental problems. As hot deserts are extreme habitats characterized by the availability of solar energy with a nearly complete absence of organic life and water, space technology achievements in designing closed ecological systems may be applicable to the design of sustainable settlements in the deserts. This review discusses the key space technology findings for closed biogenerative life support systems (CBLSS), which can simultaneously produce food, water, nutrients, fertilizers, process wastes, and revitalize air, that can be applied to hot deserts. Among them are the closed cycle of water and the acceleration of the cycling times of carbon, biogenic compounds, and nutrients by adjusting the levels of light intensity, temperature, carbon dioxide, and air velocity over plant canopies. Enhanced growth of algae and duckweed at higher levels of carbon dioxide and light intensity can be important to provide complete water recycling and augment biomass production. The production of fertilizers and nutrients can be enhanced by applying the subsurface flow wetland technology and hyper-thermophilic aerobic bacteria for treating liquid and solid wastes. The mathematical models, optimization techniques, and non-invasive measuring techniques developed for CBLSS make it possible to monitor and optimize the performance of such closed ecological systems. The results of long-duration experiments performed in BIOS-3, Biosphere 2, Laboratory Biosphere, and other ground-based closed test facilities suggest that closed water cycle can be achieved in hot-desert bioregenerative systems using the pathways of evapotranspiration, condensation, and biological wastewater treatment technologies. We suggest that the state of the art in the CBLSS design along with the possibility of using direct sunlight for

  6. Ethnopedology and soil quality of bamboo (Bambusa sp.) based agroforestry system.

    Science.gov (United States)

    Arun Jyoti, Nath; Lal, Rattan; Das, Ashesh Kumar

    2015-07-15

    It is widely recognized that farmers' hold important knowledge of folk soil classification for agricultural land for its uses, yet little has been studied for traditional agroforestry systems. This article explores the ethnopedology of bamboo (Bambusa sp.) based agroforestry system in North East India, and establishes the relationship of soil quality index (SQI) with bamboo productivity. The study revealed four basic folk soil (mati) types: kalo (black soil), lal (red soil), pathal (stony soil) and balu (sandy soil). Of these, lal mati soil was the most predominant soil type (~ 40%) in bamboo-based agroforestry system. Soil physio-chemical parameters were studied to validate the farmers' soil hierarchal classification and also to correlate with productivity of the bamboo stand. Farmers' hierarchal folk soil classification was consistent with the laboratory scientific analysis. Culm production (i.e. measure of productivity of bamboo) was the highest (27culmsclump(-1)) in kalo mati (black soil) and the lowest (19culmsclump(-1)) in balu mati (sandy soil). Linear correlation of individual soil quality parameter with bamboo productivity explained 16 to 49% of the variability. A multiple correlation of the best fitted linear soil quality parameter (soil organic carbon or SOC, water holding capacity or WHC, total nitrogen) with productivity improved explanatory power to 53%. Development of SQI from ten relevant soil quality parameters and its correlation with bamboo productivity explained the 64% of the variation and therefore, suggest SQI as the best determinant of bamboo yield. Data presented indicate that the kalo mati (black soil) is sustainable or sustainable with high input. However, the other three folk soil types (red, stony and sandy soil) are also sustainable but for other land uses. Therefore, ethnopedological studies may move beyond routine laboratory analysis and incorporate SQI for assessing the sustainability of land uses managed by the farmers'. Additional

  7. Short Communication: Soil carbon pools in different pasture systems

    Energy Technology Data Exchange (ETDEWEB)

    Cardozo, F.M. Jr.; Carneiro, R.F.V.; Leite, L.F.C.; Araujo, A.S.F.

    2016-11-01

    The aim of this study was to assess the carbon pools of a tropical soil where the native forest was replaced with different pasture systems. We studied five pasture production systems, including four monoculture systems with forage grasses such as Andropogon, Brachiaria, Panicum, and Cynodon, and an agroforestry system as well as a native vegetation plot. Greater availability of fulvic acid was detected in the agroforestry system as compared with that in the other systems. Higher lability of C was detected in the Andropogon system during the dry and rainy seasons and during the dry season in Cynodon. During the dry season, all pastures systems showed deficits in the net removal of atmospheric CO2. The structure and practices of the agroforestry system enables more carbon to be sequestered in the soil as compared with the monoculture pasture, suggesting that it is an important practice to mitigate climatic change and to improve soil quality. (Author)

  8. Estimation of Model Uncertainties in Closed-loop Systems

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Poulsen, Niels Kjølstad

    2008-01-01

    This paper describe a method for estimation of parameters or uncertainties in closed-loop systems. The method is based on an application of the dual YJBK (after Youla, Jabr, Bongiorno and Kucera) parameterization of all systems stabilized by a given controller. The dual YJBK transfer function...

  9. Material dynamics in polluted soils with different structures - comparative investigations of general soil and aggregates

    International Nuclear Information System (INIS)

    Taubner, H.

    1992-01-01

    In structured soils, a small-scale heterogeneity of physical and chemical properties will develop which results in a reduced availability of the reaction sites of the soil matrix. In view of the lack of knowledge on the conditions within the individual aggregates were carried out for characterizing the aggregates and comparing them with the soil in, general soil samples were taken from natural structure of a podzolic soil and a podazolic brown earth from two sites in the Fichtelgebirge mountains as well as a parabraun earth from East Holstein. The horizons differed with regard to their texture and structure; silty material tends to have a subpolyhedral structure and calyey material a polyhedral structure. The general soil samples and aggregate samples from the three B horizons were subjected, with comparable experimental conditions, to percolation experiments inducing a multiple acid load. The soil solution from the secondary pore system and aggregate pore system is more heterogeneus for the higher-structured subpolyhedral texture of the perdzolic soil than for the less strongly aggregated subpolyhedral structured of the podzolic brown earth. (orig.) [de

  10. Nutrient Release from Disturbance of Infiltration System Soils during Construction

    Directory of Open Access Journals (Sweden)

    Daniel P. Treese

    2012-01-01

    Full Text Available Subsurface infiltration and surface bioretention systems composed of engineered and/or native soils are preferred tools for stormwater management. However, the disturbance of native soils, especially during the process of adding amendments to improve infiltration rates and pollutant removal, may result in releases of nutrients in the early life of these systems. This project investigated the nutrient release from two soils, one disturbed and one undisturbed. The disturbed soil was collected intact, but had to be air-dried, and the columns repacked when soil shrinkage caused bypassing of water along the walls of the column. The undisturbed soil was collected and used intact, with no repacking. The disturbed soil showed elevated releases of nitrogen and phosphorus compared to the undisturbed soil for approximately 0.4 and 0.8 m of runoff loading, respectively. For the undisturbed soil, the nitrogen release was delayed, indicating that the soil disturbance accelerated the release of nitrogen into a very short time period. Leaving the soil undisturbed resulted in lower but still elevated effluent nitrogen concentrations over a longer period of time. For phosphorus, these results confirm prior research which demonstrated that the soil, if shown to be phosphorus-deficient during fertility testing, can remove phosphorus from runoff even when disturbed.

  11. Volatilization of iodine from soils and plants

    International Nuclear Information System (INIS)

    Wildung, R.E.; Cataldo, D.A.; Garland, T.R.

    1985-04-01

    Elevated levels of 129 I, a long-lived fission product, are present in the environment as a result of nuclear weapons testing and fuel reprocessing. To aid in understanding the anomalous behavior of this element, relative to natural I ( 127 I), in the vicinity of nuclear fuel reprocessing plants, preliminary laboratory-growth chamber studies were undertaken to examine the possible formation of volatile inorganic and organic I species in soil and plant systems. Inorganic 129 I added to soil was volatilized from both the soil and plant during plant growth, at average ratios of 2 x 10 -3 %/day soil and 9 x 10 -3 %/day foliage, respectively. Volatilization rates from soil were an order of magnitude less in the absence of growing roots. Less than 2% of soil or plant volatiles was subsequently retained by plant canopies. Volatile I, chemically characterized by selective sorption methods, consisted principally of alkyl iodides formed by both soil and plant processes. However, plants and soils containing actively growing roots produced a larger fraction of volatile inorganic I than soil alone. 14 refs., 1 fig., 3 tabs

  12. In situ closed-loop bioremediation: Rapid closure in a northern climate

    International Nuclear Information System (INIS)

    Weymann, D.F.; Hammerbeck, L.M.

    1995-01-01

    In situ closed-loop bioremediation was employed to achieve site closure at a former railyard in Minneapolis, Minnesota. Soil and groundwater were contaminated with gasoline. The closed-loop remediation system design incorporated three downgradient groundwater recovery wells and a low-pressure pipe infiltration gallery. Aboveground treatment of recovered groundwater was provided by a fixed-film bioreactor. The total reported benzene, toluene, ethylbenzene, and xylenes (BTEX)-removal efficiency of the bioreactor ranged from 98.8% to 100%. Concentrations of BTEX components in groundwater wells were reduced by 45% to 98%. The cleanup goals set by the Minnesota Pollution Control Agency were met within the first 6 months of treatment, and the remediation system was shut down after 20 months of operation. This project further demonstrates the effectiveness of reactor-based, closed-loop in situ bioremediation at sites with favorable conditions

  13. Microbiological parameters as indicators of soil quality under various soil management and crop rotation systems in southern Brazil.

    OpenAIRE

    FRANCHINI, J. C.; CRISPINO, C. C.; SOUZA, R. A.; TORRES, E.; HUNGRIA, M.

    2006-01-01

    Metadata only record This article attempts to recognize soil parameters that can be used to monitor soil quality under different crop and soil management systems. The rates of CO2 emissions (soil respiration) were affected by variations in the sampling period, as well as in soil management and crop rotation. Considering all samples, CO2 emissions were 21% greater in conventional tillage. Soil microbial biomass was also influenced by sampling period and soil management, but not by crop rota...

  14. Integrated vacuum extraction/pneumatic soil fracturing system for remediation of low permeability soil

    International Nuclear Information System (INIS)

    Plaines, A.L.; Piniewski, R.J.; Yarbrough, G.D.

    1994-01-01

    There is wide use of vacuum extraction to remove volatile and semi-volatile organic compounds (VOCs) from unsaturated soil. At sites with soil of low permeability, VOC extraction rates may not be sufficient to meet soil clean-up objectives within the desired time frame. During vacuum extraction in low permeability soil, the diffusion rates of VOCs through the soil matrix may limit VOC removal rates. An increase in the number of subsurface paths for advective flow through the contaminated zone results in a larger mass of contaminant being removed in a shorter time frame, accelerating site remediation. One technique for increasing the number of subsurface flow paths is Terra Vac's process of pneumatic soil fracturing (PSF). In this process, pressurized air is injected into the subsurface, creating micro-fractures for the vacuum extraction system to withdraw contaminants. Similar to hydraulic fracturing techniques long used in the petroleum industry for increasing yield from oil and gas production wells, this technique has applications for soil remediation in low permeability conditions. Two case studies, one in Louisiana at a gasoline service station and one at a manufacturing plant in New York, are presented

  15. Estimation of Parametric Fault in Closed-loop Systems

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Poulsen, Niels Kjølstad

    2015-01-01

    The aim of this paper is to present a method for estimation of parametric faults in closed-loop systems. The key technology applied in this paper is coprime factorization of both the dynamic system as well as the feedback controller. Using the Youla-Jabr-Bongiorno-Kucera (YJBK) parameterization...

  16. Soil properties mapping with the DIGISOIL multi-sensor system

    Science.gov (United States)

    Grandjean, G.

    2012-04-01

    The multidisciplinary DIGISOIL project aimed to integrate and improve in situ and proximal measurement technologies for the assessment of soil properties and soil degradation indicators, going from the sensing technologies to their integration and their application in (digital) soil mapping (DSM). In order to assess and prevent soil degradation and to benefit from the different ecological, economical and historical functions of the soil in a sustainable way, high resolution and quantitative maps of soil properties are needed. The core objective of the project is to explore and exploit new capabilities of advanced geophysical technologies for answering this societal demand. To this aim, DIGISOIL addresses four issues covering technological, soil science and economic aspects: (i) the validation of geophysical (in situ, proximal and airborne) technologies and integrated pedo-geophysical inversion techniques (mechanistic data fusion) (ii) the relation between the geophysical parameters and the soil properties, (iii) the integration of the derived soil properties for mapping soil functions and soil threats, (iv) the pre-evaluation, standardisation and sub-industrialization of the proposed methodologies, including technical and economical studies related to the societal demand. With respect to these issues, the DIGISOIL project allows to develop, test and validate the most relevant geophysical technologies for mapping soil properties. The system was tested on different field tests, and validated the proposed technologies and solutions for each of the identified methods: geoelectric, GPR, EMI, seismics, magnetic and hyperspectral. After data acquisition systems, sensor geometry, and advanced data processing techniques have been developed and validated, we present now the solutions for going from geophysical data to soil properties maps. For two test sites, located respectively in Luxembourg (LU) and Mugello (IT) a set of soil properties maps have been produced. They give

  17. Microbial Diversity in Soil Treatment Systems for Wastewater

    Science.gov (United States)

    Van Cuyk, S.; Spear, J.; Siegrist, R.; Pace, N.

    2002-05-01

    There is an increasing awareness and concern over land based wastewater system performance with respect to the removal of bacteria and virus. The goal of this work is to describe and identify the organismal composition of the microbiota in the applied wastewater effluent, the rich biomat that develops at the infiltrative surface, and in the soil percolate in order to aid in the understanding of bacterial and virus purification in soil treatment systems. The traditional reliance on pure culture techniques to describe microbiota is circumvented by the employment of a molecular approach. Microbial community characterization is underway based on cloning and sequencing of 16S rRNA genes for phylogenetic analyses, to determine the nature and quantity of microbiota that constitute these ecosystems. Knowledge of the organisms naturally present can influence the design and treatment capacity of these widely used land based systems. Laboratory, intermediate and field scale systems are currently under study. Since human pathogens are known to exist in sewage effluents, their removal in wastewater infiltration systems and within the underlying soil are in need of a more fundamental understanding. The relationship between design parameters and environmental conditions, including a microbial characterization, is essential for the prevention of contamination in groundwater sources. Preliminary results indicate the presence of uncultured organisms and phylogenetic kinds that had not been detected in these systems using other methods. Acinetobacter johnsonii and Acrobacter cryaerophilus were the two dominant species found in septic tank effluent, comprising 20% and 11% of the library respectively. In soil samples collected from the infiltrative surface of a column dosed with STE, there was no dominant bacterial species present. Percolate samples collected from the outflow of the column showed that a tuber borchii symbiont, a common soil microorganism, dominated the bacterial

  18. Kasza: Design of a closed water system for the greenhouse horticulture

    NARCIS (Netherlands)

    Velde, van der R.T.; Voogt, W.; Pickhardt, P.W.

    2008-01-01

    The need for a closed and sustainable water system in greenhouse areas is stimulated by the implementation in the Netherlands of the European Framework Directive. The Dutch national project Kasza: Design of a Closed Water System for the Greenhouse Horticulture will provide information how the water

  19. Soil as a Sustainable Resource for the Bioeconomy - BonaRes

    Science.gov (United States)

    Wollschläger, Ute; Amelung, Wulf; Brüggemann, Nicolas; Brunotte, Joachim; Gebbers, Robin; Grosch, Rita; Heinrich, Uwe; Helming, Katharina; Kiese, Ralf; Leinweber, Peter; Reinhold-Hurek, Barbara; Veldkamp, Edzo; Vogel, Hans-Jörg; Winkelmann, Traud

    2017-04-01

    Fertile soils are a fundamental resource for the production of biomass and provision of food and energy. A growing world population and latest climate targets lead to an increasing demand for bio-based products which require preserving and - ideally - improving the long-term productivity of soils as a bio-economic resource. At the same time, other soil functions and ecosystem services need to be maintained: filter for clean water, carbon sequestration, provision and recycling of nutrients, and habitat for biological activity. All these soil functions result from the interaction of a multitude of physical, chemical and biological processes which are insufficiently understood. In addition, we lack understanding about the interplay between the socio-economic system and the soil system and how soil functions benefit human wellbeing, including SDGs. However, a solid and integrated assessment of soil quality requires the consideration of the ensemble of soil functions and its relation to soil management. To make soil management sustainable, we need to establish a scientific knowledge base of complex soil system processes that allows for developing models and tools to quantitatively predict the impact of a multitude of management measures on soil functions. This will finally allow for the provision of options for a site-specific, sustainable soil management. To face this challenge, the German Federal Ministry of Education and Research (BMBF) recently launched the funding program "Soil as a Sustainable Resource for the Bioeconomy - BonaRes". In a joint effort, ten collaborative projects and the coordinating BonaRes Centre are engaged to close existing knowledge gaps for a profound and systemic assessment and understanding of soil functions and their sensitivity to soil management. In BonaRes, the complete process chain of sustainable soil use in the context of a sustainable bio-economy is being addressed: from understanding of soil processes using state-of the art and

  20. Transfer of technetium in the soil-rice plant system

    International Nuclear Information System (INIS)

    Yanagisawa, K.; Muramatsu, Y.

    1995-01-01

    In order to assess the behavior of Tc in flooded soil-plant systems, laboratory experiments have been done using 95m Tc as a tracer. Two common soil types in Japan, Andosol and Gray lowland soils, were used. Soil-plant transfer factors of Tc in rice grain were very low, i.e. 5 x 10 -5 for Andosol and 6 x 10 -4 for Gray lowland soil. It was found that the Tc concentrations in rice plants were influenced by those in soil solutions. Concentrations of 95m Tc in both soil solutions decreased rapidly in the early period of cultivation. It was observed that redox-potential (Eh) also decreased markedly following flooding. A relationship was found between the decrease of the 95m Tc concentrations in soil solutions and the drop of Eh in the soils. The Tc (VII) added to soil was transformed to insoluble Tc (IV) under the reduced conditions existing in flooded soil. (author). 10 refs., 2 figs., 4 tabs

  1. [Evaluation of two closed-system drug transfer device in the antineoplastic drug elaboration process].

    Science.gov (United States)

    Gómez-Álvarez, Sandra; Porta-Oltra, Begoña; Hernandez-Griso, Marta; Pérez-Labaña, Francisca; Climente-Martí, Mónica

    2016-01-01

    to assess the impact of two closed-system drug transfer device on the local and environmental contamination and preparation times in the process of preparation of parenteral chemotherapy compared to the standard system. prospective observational study. Two different closed- systems providers, Care Fusion® and Icu Medical®, were compared to standard preparation. 15 nurses of Pharmacy Department prepared 5 preparations each one, one with the standard procedure and four using closed-systems. To evaluate the contamination, a fluorescein solution 0.5% was prepared. Two kind of contamination were evaluated, local (three points connection: closed-system connect vial, syringe and final infusion bags) and environmental (gloves and countertop). Percentage of contaminated preparations was obtained in each one. Time taken by each nurse in each preparation was recorded. 75 preparations were prepared. Local contamination was reduced 21% and 75% in closed-system Icu Medical® and Care Fusion® respectively. Care Fusion® closed system, local contamination was significantly lower than the standard system to the vial, syringe and final package, while Icu Medical® closed-systems only was significantly lower in the connection to the vial. Time of preparation was increased significantly with the use of closed-system between 23.4 and 30.5 seconds. both closed-systems drug transfer device have shown an improvement in contamination than the use of the standard system. However, preparation time has been significantly increased with the use of both systems. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

  2. Permanent-magnet-less synchronous reluctance system

    Science.gov (United States)

    Hsu, John S

    2012-09-11

    A permanent magnet-less synchronous system includes a stator that generates a magnetic revolving field when sourced by an alternating current. An uncluttered rotor is disposed within the magnetic revolving field and spaced apart from the stator to form an air gap relative to an axis of rotation. The rotor includes a plurality of rotor pole stacks having an inner periphery biased by single polarity of a north-pole field and a south-pole field, respectively. The outer periphery of each of the rotor pole stacks are biased by an alternating polarity.

  3. Distributed security in closed distributed systems

    DEFF Research Database (Denmark)

    Hernandez, Alejandro Mario

    properties. This is also restricted to distributed systems in which the set of locations is known a priori. All this follows techniques borrowed from both the model checking and the static analysis communities. In the end, we reach a step towards solving the problem of enforcing security in distributed...... systems. We achieve the goal of showing how this can be done, though we restrict ourselves to closed systems and with a limited set of enforceable security policies. In this setting, our approach proves to be efficient. Finally, we achieve all this by bringing together several fields of Computer Science......The goal of the present thesis is to discuss, argue and conclude about ways to provide security to the information travelling around computer systems consisting of several known locations. When developing software systems, security of the information managed by these plays an important role...

  4. Monitoring soil carbon will prepare growers for a carbon trading system

    Directory of Open Access Journals (Sweden)

    Emma C. Suddick

    2013-07-01

    Full Text Available California growers could reap financial benefits from the low-carbon economy and cap-and-trade system envisioned by the state's AB 32 law, which seeks to lower greenhouse gas emissions statewide. Growers could gain carbon credits by reducing greenhouse gas emissions and sequestering carbon through reduced tillage and increased biomass residue incorporation. First, however, baseline stocks of soil carbon need to be assessed for various cropping systems and management practices. We designed and set up a pilot soil carbon and land-use monitoring network at several perennial cropping systems in Northern California. We compared soil carbon content in two vineyards and two orchards (walnut and almond, looking at conventional and conservation management practices, as well as in native grassland and oak woodland. We then calculated baseline estimates of the total carbon in almond, wine grape and walnut acreages statewide. The organic walnut orchard had the highest total soil carbon, and no-till vineyards had 27% more carbon in the surface soil than tilled vineyards. We estimated wine grape vineyards are storing significantly more soil carbon per acre than almond and walnut orchards. The data can be used to provide accurate information about soil carbon stocks in perennial cropping systems for a future carbon trading system.

  5. Spatial Variation of Soil Type and Soil Moisture in the Regional Atmospheric Modeling System

    Energy Technology Data Exchange (ETDEWEB)

    Buckley, R.

    2001-06-27

    Soil characteristics (texture and moisture) are typically assumed to be initially constant when performing simulations with the Regional Atmospheric Modeling System (RAMS). Soil texture is spatially homogeneous and time-independent, while soil moisture is often spatially homogeneous initially, but time-dependent. This report discusses the conversion of a global data set of Food and Agriculture Organization (FAO) soil types to RAMS soil texture and the subsequent modifications required in RAMS to ingest this information. Spatial variations in initial soil moisture obtained from the National Center for Environmental Predictions (NCEP) large-scale models are also introduced. Comparisons involving simulations over the southeastern United States for two different time periods, one during warmer, more humid summer conditions, and one during cooler, dryer winter conditions, reveals differences in surface conditions related to increases or decreases in near-surface atmospheric moisture con tent as a result of different soil properties. Three separate simulation types were considered. The base case assumed spatially homogeneous soil texture and initial soil moisture. The second case assumed variable soil texture and constant initial soil moisture, while the third case allowed for both variable soil texture and initial soil moisture. The simulation domain was further divided into four geographically distinct regions. It is concluded there is a more dramatic impact on thermodynamic variables (surface temperature and dewpoint) than on surface winds, and a more pronounced variability in results during the summer period. While no obvious trends in surface winds or dewpoint temperature were found relative to observations covering all regions and times, improvement in surface temperatures in most regions and time periods was generally seen with the incorporation of variable soil texture and initial soil moisture.

  6. Soil quality assessment of rice production systems in South of Brazil

    NARCIS (Netherlands)

    Rodrigues de Lima, A.C.; Hoogmoed, W.B.; Brussaard, L.

    2007-01-01

    Soil quality, as a measure of the soil capacity to function, can be quantified by indicators based on physical, chemical and biological properties. Maintaining soil quality at a desirable level in the rice cropping system is a very complex issue due to the nature of the production systems used. In

  7. Response of Soil Temperature to Climate Change in the CMIP5 Earth System Models

    Science.gov (United States)

    Phillips, C. L.; Torn, M. S.; Koven, C. D.

    2014-12-01

    Predictions of soil temperature changes are as critical to policy development and climate change adaptation as predictions of air temperature, but have received comparatively little attention. Soil temperature determines seed germination and growth of wild and agricultural plants, and impacts climate through both geophysical and carbon-cycle feedbacks. The Intergovernmental Panel on Climate Change 5th Assessment Report does not report soil temperature predictions, but focuses instead on surface air temperatures, despite the fact that mean annual soil temperatures and mean surface air temperatures are often different from each other. Here we aim to fill this important knowledge gap by reporting soil temperature and moisture predictions for 15 earth system models (ESMs) that participated in phase 5 of the Coupled Model Intercomparison 5 Project (CMIP5). Under the RCP 4.5 and 8.5 emissions scenarios, soil warming is predicted to almost keep pace with soil air warming, with about 10% less warming in soil than air, globally. The slower warming of soil compared to air is likely related to predictions of soil drying, with drier soils having reduced soil heat capacity and thermal conductivity. Mollisol soils, which are typically regarded as the most productive soil order for cultivating cereal crops, are anticipated to see warming in North America of 3.5 to 5.5 °C at the end of the 21st century (2080-2100) compared to 1986-2005. One impact of soil warming is likely to be an acceleration of germination timing, with the 3°C temperature threshold for wheat germination anticipated to advance by several weeks in Mollisol regions. Furthermore, soil warming at 1 m depth is predicted to be almost equivalent to warming at 1 cm depth in frost-free regions, indicating vulnerability of deep soil carbon pools to destabilization. To assess model performance we compare the models' predictions with observations of damping depth, and offsets between mean annual soil and air temperature

  8. Availability of 99Tc in undisturbed soil cores

    International Nuclear Information System (INIS)

    Denys, Sebastien; Echevarria, Guillaume; Florentin, Louis; Leclerc-Cessac, Elisabeth; Morel, Jean-Louis

    2003-01-01

    Models for safety assessment of radioactive waste repositories need accurate values of the soil-to-plant transfer of radionuclides. In oxidizing environments, 99 Tc is expected to occur as pertechnetate ( 99 TcO 4 - ). Due to its high mobility, leaching of this element in the field might be important, potentially affecting the reliability of estimated transfer parameters of 99 Tc as measured in closed experimental systems such as hydroponics or pot experiments. The aim of this experiment was to measure the leaching of 99 Tc in undisturbed irrigated soil cores under cultivation as well as plant uptake and to study the possible competition between the two transfer pathways. Undisturbed soil cores (50x50 cm) were sampled from a Rendzic Leptosol (R), a colluvial Fluvic Cambisol (F) and a Dystric Cambisol (D) using PVC tubes (three cores sampled per soil type). Each core was equipped with a leachate collector at the bottom, allowing the monitoring of 99 Tc leaching through the cores. Cores were placed in a greenhouse and maize (Zea mays L., cv. DEA, Pioneer[reg]) was sown. After 135 d, maize was harvested and radioactivity determined in both plant and water samples. Results showed that during the growing period, leaching of 99 Tc was limited, due to the high evapotranspiration rate of maize. After harvest, leaching of 99 Tc went on because of the absence of evapotranspiration. Effective uptake (EU) of 99 Tc in leaves and grains was calculated. EU reached 70% of the input in the leaves and was not significantly different among soils. These results confirmed those obtained from pot experiments, even though leaching was allowed to occur in close-to-reality hydraulical conditions. As a consequence, it was concluded that pot experiments are an adequate surrogate for more complex 'close-to-reality' experimental systems for measuring transfer factors

  9. Benchmarking a Soil Moisture Data Assimilation System for Agricultural Drought Monitoring

    Science.gov (United States)

    Hun, Eunjin; Crow, Wade T.; Holmes, Thomas; Bolten, John

    2014-01-01

    Despite considerable interest in the application of land surface data assimilation systems (LDAS) for agricultural drought applications, relatively little is known about the large-scale performance of such systems and, thus, the optimal methodological approach for implementing them. To address this need, this paper evaluates an LDAS for agricultural drought monitoring by benchmarking individual components of the system (i.e., a satellite soil moisture retrieval algorithm, a soil water balance model and a sequential data assimilation filter) against a series of linear models which perform the same function (i.e., have the same basic inputoutput structure) as the full system component. Benchmarking is based on the calculation of the lagged rank cross-correlation between the normalized difference vegetation index (NDVI) and soil moisture estimates acquired for various components of the system. Lagged soil moistureNDVI correlations obtained using individual LDAS components versus their linear analogs reveal the degree to which non-linearities andor complexities contained within each component actually contribute to the performance of the LDAS system as a whole. Here, a particular system based on surface soil moisture retrievals from the Land Parameter Retrieval Model (LPRM), a two-layer Palmer soil water balance model and an Ensemble Kalman filter (EnKF) is benchmarked. Results suggest significant room for improvement in each component of the system.

  10. Soil aggregation and organic carbon of Oxisols under coffee in agroforestry systems

    Directory of Open Access Journals (Sweden)

    Gabriel Pinto Guimarães

    2014-02-01

    Full Text Available Intensive land use can lead to a loss of soil physical quality with negative impacts on soil aggregates, resistance to root penetration, porosity, and bulk density. Organic and agroforestry management systems can represent sustainable, well-balanced alternatives in the agroecosystem for promoting a greater input of organic matter than the conventional system. Based on the hypothesis that an increased input of organic matter improves soil physical quality, this study aimed to evaluate the impact of coffee production systems on soil physical properties in two Red-Yellow Oxisols (Latossolos Vermelho-Amarelos in the region of Caparaó, Espirito Santo, Brazil. On Farm 1, we evaluated the following systems: primary forest (Pf1, organic coffee (Org1 and conventional coffee (Con1. On Farm 2, we evaluated: secondary forest (Sf2, organic coffee intercropped with inga (Org/In2, organic coffee intercropped with leucaena and inga (Org/In/Le2, organic coffee intercropped with cedar (Org/Ced2 and unshaded conventional coffee (Con2. Soil samples were collected under the tree canopy from the 0-10, 10-20 and 20-40 cm soil layers. Under organic and agroforestry coffee management, soil aggregation was higher than under conventional coffee. In the agroforestry system, the degree of soil flocculation was 24 % higher, soil moisture was 80 % higher, and soil resistance to penetration was lower than in soil under conventional coffee management. The macroaggregates in the organic systems, Org/In2, Org/In/Le2, and Org/Ced2 contained, on average, 29.1, 40.1 and 34.7 g kg-1 organic carbon, respectively. These levels are higher than those found in the unshaded conventional system (Con2, with 20.2 g kg-1.

  11. An application of observer for position sensor less stepper motor drives

    International Nuclear Information System (INIS)

    Nor Arymaswati Abdullah; Salinda Buyamin; Glam Hadzir Patai Mohamad; Abu Bakar Ghazali

    2010-01-01

    A control method for stepper motor drives system can be made in open-loop circumstance which mean the system control did not require any feedback input signal in order to run the system. By applying the right sequences of pulses, the stepper motor capable to operate as other motion control. However, the performance of such system cannot be achieved to high level condition and demanded a feedback signal input to compensate the error produced while running the drive system. Therefore, a physical sensor or an encoder is placed in the motor system to obtain the feedback and form a close-loop system for error compensation. Nevertheless, the prices of these instruments are expensive, bulky and also may degrade the system performance. As a result this project presents a sensor less system in stepper motor drive system as an alternative to develop a close-loop system where the input signals are taken from voltage and current of the magnetic flux of the stepper motor. (author)

  12. Modeling and Analysis of a Closed-Loop System for High-Q MEMS Accelerometer Sensor

    Directory of Open Access Journals (Sweden)

    Wang Yalin

    2018-01-01

    Full Text Available High-Q sensing element is desirable for high performance while makes the loop control a great challenge. This paper presents a closed-loop system for high-Q capacitive MEMS accelerometer which has achieved loop control effectively. The proportional-derivative(PDcontrol is developed in the system to improve the system stability. In addition, pulse width modulation (PWM electrostatic force feedback is designed in the loop to overcome the nonlinearity. Furthermore, a sigma-delta (ΣΔ modulator with noise shaping is built to realize digital output. System model is built in Matlab/Simulink. The simulation results indicate that equivalent Q value is reduced to 1.5 to ensure stability and responsiveness of the system. The effective number of bits of system output is 14.7 bits. The system nonlinearity is less than 5‰. The equivalent linear model including main noise factors is built, and then a complete theory of noise and linearity analysis is established to contribute to common MEMS accelerometer research.

  13. Simulating soil greenhouse emissions from Swiss long-term cropping system trials

    Science.gov (United States)

    Necpalova, Magdalena; Lee, Juhwan; Skinner, Colin; Büchi, Lucie; Berner, Alfred; Mäder, Paul; Mayer, Jochen; Charles, Raphael; van der Heijden, Marcel; Wittwer, Raphael; Gattinger, Andreas; Six, Johan

    2017-04-01

    There is an urgent need to identify and evaluate management practices for their bio-physical potential to mitigate greenhouse gas (GHG) emissions from agriculture. The cost and time required for direct management-specific GHG measurements limit the spatial and temporal resolution and the extent of data that can be collected. Biogeochemical process-based models such as DayCent can be used to bridge data gaps over space and time and estimate soil GHG emissions relevant to various climate change mitigation strategies. Objectives of this study were (a) to parameterize DayCent for common Swiss crops and crop-specific management practices using the Swiss long-term experimental data collected at four sites (Therwil, Frick, Changins, and Reckenholz); (b) to evaluate the model's ability to predict crop productivity, long-term soil carbon dynamics and N2O emissions from Swiss cropping systems; (c) to calculate a net soil GHG balance for all treatments (except for bio-dynamic) studied in long-term field experiments in Switzerland; and (d) to study the management effects and their interactions on soil GHG emissions at each experimental site. Model evaluation indicated that DayCent predicted crop productivity (rRMSE=0.29 r2=0.81, n=2614), change in soil carbon stock (rRMSE=0.14, r2=0.72, n=1289) and cumulative N2O emissions (rRMSE=0.25, r2=0.89, n=8) satisfactorily across all treatments and sites. Net soil GHG emissions were derived from changes in soil carbon, N2O emissions and CH4 oxidation on an annual basis using IPCC (2014) global warming potentials. Modelled net soil GHG emissions calculated for individual treatments over 30 years ranged from -594 to 1654 kg CO2 eq ha-1 yr-1. The highest net soil GHG emissions were predicted for conventional tillage and slurry application treatment at Frick, while soils under organic and reduced tillage management at Reckenholz acted as a net GHG sink. The statistical analyses using linear MIXED models indicated that net soil GHG

  14. COSMOS: the COsmic-ray Soil Moisture Observing System

    Directory of Open Access Journals (Sweden)

    M. Zreda

    2012-11-01

    Full Text Available The newly-developed cosmic-ray method for measuring area-average soil moisture at the hectometer horizontal scale is being implemented in the COsmic-ray Soil Moisture Observing System (or the COSMOS. The stationary cosmic-ray soil moisture probe measures the neutrons that are generated by cosmic rays within air and soil and other materials, moderated by mainly hydrogen atoms located primarily in soil water, and emitted to the atmosphere where they mix instantaneously at a scale of hundreds of meters and whose density is inversely correlated with soil moisture. The COSMOS has already deployed more than 50 of the eventual 500 cosmic-ray probes, distributed mainly in the USA, each generating a time series of average soil moisture over its horizontal footprint, with similar networks coming into existence around the world. This paper is written to serve a community need to better understand this novel method and the COSMOS project. We describe the cosmic-ray soil moisture measurement method, the instrument and its calibration, the design, data processing and dissemination used in the COSMOS project, and give example time series of soil moisture obtained from COSMOS probes.

  15. Closed vessels microwave digestion method for uranium analysis of soils using alpha-spectroscopy

    International Nuclear Information System (INIS)

    Salar Amoli, H.; Barker, J.; Flowers, A.

    2007-01-01

    This paper describes our development of an accurate determination of uranium by alpha spectrometry using various kinds of sample digestion methods. The sample preparation techniques employed an acid digestion with HNO 3 , and microwave oven digestion either by HNO 3 or by combination of HNO 3 and HF. The samples were obtained from surface and in depth(40 cm) soils from residential area. An extraction chromatography column has been used to separate the uranium from interference matrix and elements. Results show that the microwave method significantly speeds up the analysis time, reduces the volume of acids used and eliminates a large fraction of acid vapour emission. Compared with the uranium recoveries it was shown that microwave HNO 3 +HF achieved greater recovery (83%) than microwave HNO 3 (78%), while less obtained by HNO 3 digestion using hot plate (75%). Various kind of digestion methods have been applied (24 times) for two kind of soil sample . The reproducibility was acceptable and the average precision (coefficient of variation) was between 4 to 5. No significant differences between the precision of the methods have been observed. Acid volume required for the microwave procedures are a fraction of 5 times lower and the analysis time 6 times lower than traditional digestion by hot plate technique. (author)

  16. A fully continuous supercritical fluid extraction system for contaminated soil

    International Nuclear Information System (INIS)

    Ryan, M.; Stiver, W.H.

    2007-01-01

    Brownfield sites are contaminated sites in an urban setting. There are hundreds of thousands of such sites, where contaminants migrate to the atmosphere, seep into groundwater, runoff into surface water and enter the food chain through plant uptake and soil ingestion. The Sydney Tar Ponds alone contain more than a million tonnes of contaminated soils and sediments. Soil vapour extraction, incineration, bioremediation, solvent extraction and land filling are among the remediation techniques that have been developed for brownfield sites over the years. However, no single technology is ideally suited to all cases because of the diversity of contaminants and diversity of site characterization. This paper focused on supercritical fluid extraction (SFE) which is well suited to sites contaminated with polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and heavy metal. A fully continuous laboratory-scale SFE process for a slurry-based system was designed and constructed to handle the supercritical carbon dioxide (SC-CO 2 ) and the soil slurry. The system continuously pumps carbon dioxide under supercritical conditions and soil slurry into a counter-current contacting column. The testing soil was Delhi loamy sand, spiked with 10 mg/g of naphthalene. The soil slurry ranged from 0.0028 g dry soil per g slurry to 0.072 g/g. The operating temperature was 43 degrees C and the operating pressure was 7.7 MPa. Near steady state, fully continuous flow was achieved with runs lasting up to 2 hours. The quantifiable recoveries of naphthalene from the soil slurry was demonstrated and the mass transfer coefficients for the system were quantified in order to provide the foundation to advance to a full-scale system and costing analysis. 14 refs., 1 tab., 3 figs

  17. A fully continuous supercritical fluid extraction system for contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Ryan, M.; Stiver, W.H. [Guelph Univ., ON (Canada). School of Engineering

    2007-04-15

    Brownfield sites are contaminated sites in an urban setting. There are hundreds of thousands of such sites, where contaminants migrate to the atmosphere, seep into groundwater, runoff into surface water and enter the food chain through plant uptake and soil ingestion. The Sydney Tar Ponds alone contain more than a million tonnes of contaminated soils and sediments. Soil vapour extraction, incineration, bioremediation, solvent extraction and land filling are among the remediation techniques that have been developed for brownfield sites over the years. However, no single technology is ideally suited to all cases because of the diversity of contaminants and diversity of site characterization. This paper focused on supercritical fluid extraction (SFE) which is well suited to sites contaminated with polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and heavy metal. A fully continuous laboratory-scale SFE process for a slurry-based system was designed and constructed to handle the supercritical carbon dioxide (SC-CO{sub 2}) and the soil slurry. The system continuously pumps carbon dioxide under supercritical conditions and soil slurry into a counter-current contacting column. The testing soil was Delhi loamy sand, spiked with 10 mg/g of naphthalene. The soil slurry ranged from 0.0028 g dry soil per g slurry to 0.072 g/g. The operating temperature was 43 degrees C and the operating pressure was 7.7 MPa. Near steady state, fully continuous flow was achieved with runs lasting up to 2 hours. The quantifiable recoveries of naphthalene from the soil slurry was demonstrated and the mass transfer coefficients for the system were quantified in order to provide the foundation to advance to a full-scale system and costing analysis. 14 refs., 1 tab., 3 figs.

  18. The solar system in close-up

    CERN Document Server

    Wilkinson, John

    2016-01-01

    In response to the new information gained about the Solar System from recent space probes and space telescopes, the experienced science author Dr. John Wilkinson presents the state-of-the art knowledge on the Sun, solar system planets and small solar system objects like comets and asteroids. He also describes space missions like the New Horizon’s space probe that provided never seen before pictures of the Pluto system; the Dawn space probe, having just visited the asteroid Vesta, and the dwarf planet Ceres; and the Rosetta probe inorbit around comet 67P/Churyumov–Gerasimenko that has sent extraordinary and most exciting pictures. Those and a number of other probes are also changing our understanding of the solar system and providing a wealth of new up close photos. This book will cover all these missions and discuss observed surface features of planets and moons like their compositions, geisers, aurorae, lightning phenomena etc. Presenting the fascinating aspects of solar system astronomy this book is a c...

  19. Mineralogy of Antarctica Dry Valley Soils: Implications for Pedogenic Processes on Mars

    Science.gov (United States)

    Quinn, J. E.; Ming, D. W.; Morris, R. V.; Douglas, S.; Kounaves, S. P.; McKay, C. P.; Tamppari, L, K.; Smith, P. H.; Zent, A. P.; Archer, P. D., Jr.

    2010-01-01

    The Antarctic Dry Valleys (ADVs) located in the Transantarctic Mountains are the coldest and driest locations on Earth. The mean annual air temperature is -20 C or less and the ADVs receive 100mm or less of precipitation annually in the form of snow. The cold and dry climate in the ADVs is one of the best terrestrial analogs for the climatic conditions on Mars [2]. The soils in the ADVs have been categorized into three soil moisture zones: subxerous, xerous and ultraxerous. The subxerous zone is a coastal region in which soils have ice-cemented permafrost relatively close to the surface. Moisture is available in relatively large amounts and soil temperatures are above freezing throughout the soil profile (above ice permafrost) in summer months. The xerous zone, the most widespread of the three zones, is an inland region with a climate midway between the subxerous and ultraxerous. The soils from this zone have dry permafrost at moderate depths (30-75cm) but have sufficient water in the upper soil horizons to allow leaching of soluble materials. The ultraxerous zone is a high elevation zone, where both temperature and precipitation amounts are very low resulting in dry permafrost throughout the soil profile. The three moisture regime regions are similar to the three microclimatic zones (coastal thaw, inland mixed, stable upland) defined by Marchant and Head.

  20. NEW TRENDS IN AGRICULTURE - CROP SYSTEMS WITHOUT SOIL

    Directory of Open Access Journals (Sweden)

    Ioan GRAD

    2014-04-01

    Full Text Available The paper studied new system of agriculture - crop systems without soil. The culture systems without soil can be called also the hydroponic systems and now in Romania are not used only sporadically. In other countries (USA, Japan, the Netherlands, France, UK, Denmark, Israel, Australia, etc.. they represent the modern crop technology, widely applied to vegetables, fruits, fodder, medicinal plants and flowers by the experts in this area. In the world, today there are millions of hectares hydroponics, most of the vegetables, herbs, fruits of hypermarkets are coming from the culture systems without soil. The process consists of growing plants in nutrient solutions (not in the ground, resorting to an complex equipment, depending on the specifics of each crop, so that the system can be applied only in the large farms, in the greenhouses, and not in the individual households. These types of culture systems have a number of advantages and disadvantages also. Even if today's culture systems without soil seem to be the most modern and surprising technology applied in plant growth, the principle is very old. Based on him were built The Suspended Gardens of the Semiramis from Babylon, in the seventh century BC, thanks to him, the population from the Peru”s highlands cultivates vegetables on surfaces covered with water or mud. The peasant households in China, even today use the millenary techniques of the crops on gravel. .This hydroponic agriculture system is a way of followed for Romanian agriculture too, despite its high cost, because it is very productive, ecological, can cover, by products, all market demands and it answer, increasingly, constraints of urban life. The concept of hydroponics agriculture is known and appreciated in Romania also, but more at the theory level.

  1. Atmospheric dynamics of combined crops of wheat, cowpea, pinto beans in the Laboratory Biosphere closed ecological system

    Science.gov (United States)

    Dempster, W.; Nelson, M.; Silverstone, S.; Allen, J.; Alling, A.; van Thillo, M.

    A mixed crop consisting of cowpeas pinto beans and Apogee ultra-dwarf wheat was grown in Laboratory Biosphere a 40 m 3 closed life system equipped with 12000 watts of high pressure sodium lamps over planting beds with 5 37 m 2 of soil Similar to earlier reported experiments the concentration of carbon dioxide initially increased to 7860 ppm at 10 days after planting due to soil respiration plus CO 2 contributed from researchers breathing while in the chamber for brief periods before plant growth became substantial fell rapidly as plant growth increased up to 29 days after planting and then was maintained mostly in the range of about 200 -- 3000 ppm with a few excursions by CO 2 injections to feed plant growth Numerous analyses of rate of change of CO 2 concentration at many different concentrations and at many different days after planting reveals a strong dependence of fixation rates on CO 2 concentration In the middle period of growth days 31 -- 61 fixation rates doubled for CO 2 at 450 ppm compared to 270 ppm doubled again at 1000 ppm and increased a further 50 at 2040 ppm High productivity from these crops and the increase of fixation rates with elevated CO 2 concentration supports the concept that enhanced CO2 can be a useful strategy for remote life support systems

  2. Effect of soil amendments and crop varieties on the amelioration of heavy metal uptake into crops from polluted soils in Bangladesh

    International Nuclear Information System (INIS)

    Ullah, S.M.; Chamon, S.A.; Gerzabek, M.H.; Herger, P.

    1999-06-01

    Bangladesh has at present about 30000 industrial units, large and small. They are discharging their wastes and effluents in the natural systems in most cases without any treatment and thereby cause environmental pollution especially due to heavy metals and organic toxins. The hazardous wastes and effluents are generally discharged in low-lying areas, along the road sides or in the vicinity of the industrial installations. Besides, fertilizers and pesticides are being randomly used in agricultural lands by the uneducated farmers. The important heavy metals discharged from industries in Bangladesh are cadmium, lead, chromium, mercury, zinc, arsenic and in few cases copper and manganese. The need for the present project emerged from the results of the previous project 'Studies on heavy metal and microbiological pollution of soils, sediments and water systems in and around Dhaka City' (1993 - 1996, Nuruzzaman et al., 1995). This investigation showed that industrial effluents and wastes lead to significant pollution of soils and plants around Dhaka City. Two sites (Hazaribagh and Tongi) were investigated in detail. In the Hazahbagh tannery area significant pollution of soil profiles with Cr (up to 29400 mg/kg), Zn, Cu and Pb was observed. This resulted partly in excess heavy metal levels in plants. At the Tongi site soil exhibited high contaminations with Zn (up to 4980 mg Zn/kg) and Hg (up to 5 mg/kg). Due to pH-changes close to the battery factory the mobile Zn-fraction was extremely high and far above toxic limits for plants. Distinct differences were observed between plant species. Rice was less severely affected than wheat, which failed to form grains on the contaminated soil. An additional MSc-thesis (Mondol, 1995) focused on the Tejgaon industrial area (Dhaka). The soil especially showed access levels of Cd (163 mg/kg) and Ni (194 mg/kg), which caused distinctly lower yields of rice, wheat and lettuce and excess levels of heavy metals in plant tissues. Especially

  3. Enhancing productivity of salt affected soils through crops and cropping system

    International Nuclear Information System (INIS)

    Singh, S.S.; Khan, A.R.

    2002-05-01

    The reclamation of salt affected soils needs the addition of soil amendment and enough water to leach down the soluble salts. The operations may also include other simple agronomic techniques to reclaim soils and to know the crops and varieties that may be grown and other management practices which may be followed on such soils (Khan, 2001). The choice of crops to be grown during reclamation of salt affected soils is very important to obtain acceptable yields. This also decides cropping systems as well as favorable diversification for early reclamation, desirable yield and to meet the other requirements of farm families. In any salt affected soils, the following three measures are adopted for reclamation and sustaining the higher productivity of reclaimed soils. 1. Suitable choice of crops, forestry and tree species; 2. Suitable choice of cropping and agroforestry system; 3. Other measures to sustain the productivity of reclaimed soils. (author)

  4. General review of solar-powered closed sorption refrigeration systems

    International Nuclear Information System (INIS)

    Sarbu, Ioan; Sebarchievici, Calin

    2015-01-01

    Highlights: • Provide review of development in solar sorption refrigeration technologies. • Theoretical basis and applications of absorption and adsorption cycles are discussed. • Thermodynamic properties of most common working pairs have been reviewed. • Development of hybrid or thermal energy storage adsorption systems was explored. • A comparison between solar-powered absorption and adsorption systems was performed. - Abstract: The negative environmental impacts of burning fossil fuels have forced the energy research community seriously to consider renewable sources, such as naturally available solar energy. Thermally powered refrigeration technologies are classified into two categories: thermo-mechanical technology and sorption technology (open systems or closed systems). This paper provides a detailed review of the solar closed sorption (absorption and adsorption) refrigeration systems, which utilise working pairs (fluids). After an introduction of the basic principles of these systems, the history of development and recent advances in solar sorption refrigeration technologies are reported. The adsorption cooling typically has a lower heat source temperature requirement than the absorption cooling. Based on the coefficient of performance (COP), the absorption systems are preferred over the adsorption systems, and the higher temperature issues can be easily handled with solar adsorption systems. The thermodynamic properties of most common working fluids, as well as the use of ternary mixtures in solar-powered absorption systems, have been reviewed in this study. The paper also refers to new approaches to increase the efficiency and sustainability of the basic adsorption cycles, such as the development of hybrid or thermal energy storage adsorption systems. This research shows that solar-powered closed sorption refrigeration technologies can be attractive alternatives not only to serve the needs for air-conditioning, refrigeration, ice making, thermal

  5. [Zoological diagnostics of soils: imperatives, purposes, and place within soil zoology and pedology].

    Science.gov (United States)

    Mordokovich, V G

    2013-01-01

    Zoological diagnostics of soils was conceived by M.S. Ghilarov as a part of soil zoology and intended to be closely related to pedology. He considered zoo-agents as an ecological factor, one among many others, of soil formation. Contemporary soil diagnostics pursues mostly utilitarian goals and is based on conservative properties of the stable part of soil substrate. However, it is admitted that these properties are generated by specific combinations of biological, chemical, and physical phenomena that are called "elementary soil processes" (ESP) and occur nowhere but in soils. Certain ESPs are associated with distinctive combinations of biota, including invertebrates. Pedobionts act as producers of detritus and contribute to humus formation, which is necessary for any ESP starting, thus being its active party. That is why animals, being the most complex and active part of the ESP system, may be treated not only as its indicators but also as its navigators. Monitoring and studying of ESPs in soil is complicated because of inevitable disturbance of soil profile natural composition. Zoo-agents, at the same time, can be registered without habitats changing. Taking into account ecological potency of soil invertebrates that participate in an ESP, spectra of their eco-groups, life forms, and results of their activity, it is possible to diagnose a soil state at different stages of certain ESPs development, with their different combinations, and in different regions or parts of natural environmental gradients.

  6. Remote Multi-layer Soil Temperature Monitoring System Based on GPRS

    Directory of Open Access Journals (Sweden)

    Ming Kuo CHEN

    2014-02-01

    Full Text Available There is the temperature difference between the upper and lower layer of the shallow soil in the forest. It is a potential energy that can be harvested by thermoelectric generator for the electronic device in the forest. The temperature distribution at different depths of the soil is the first step for thermoelectric generation. A remote multi-layer soil temperature monitoring system based on GPRS is proposed in this paper. The MSP430F149 MCU is used as the main controller of multi-layer soil temperature monitoring system. A temperature acquisition module is designed with DS18B20 and 4 core shielded twisted-pair cable. The GPRS module sends the measured data to remote server through wireless communication network. From the experiments in the campus of Beijing Forestry University, the maximum error of measured temperature in this system is 0.2°C by comparing with professional equipment in the same condition. The results of the experiments show that the system can accurately realize real-time monitoring of multi-layer soil temperature, and the data transmission is stable and reliable.

  7. Application of CarboSOIL model to predict the effects of climate change on soil organic carbon stocks in agro-silvo-pastoral Mediterranean management systems

    Science.gov (United States)

    Muñoz-Rojas, Miriam; Doro, Luca; Ledda, Luigi; Francaviglia, Rosa

    2014-05-01

    CarboSOIL is an empirical model based on regression techniques and developed to predict soil organic carbon contents (SOC) at standard soil depths of 0-25, 25-50 and 50-75 cm (Muñoz-Rojas et al., 2013). The model was applied to a study area of north-eastern Sardinia (Italy) (40° 46'N, 9° 10'E, mean altitude 285 m a.s.l.), characterized by extensive agro-silvo-pastoral systems which are typical of similar areas of the Mediterranean basin (e.g. the Iberian peninsula). The area has the same soil type (Haplic Endoleptic Cambisols, Dystric according to WRB), while cork oak forest (Quercus suber L.) is the potential native vegetation which has been converted to managed land with pastures and vineyards in recent years (Lagomarsino et al., 2011; Francaviglia et al., 2012; Bagella et al, 2013; Francaviglia et al., 2014). Six land uses with different levels of cropping intensification were compared: Tilled vineyards (TV); No-tilled grassed vineyards (GV); Hay crop (HC); Pasture (PA); Cork oak forest (CO) and Semi-natural systems (SN). The HC land use includes oats, Italian ryegrass and annual clovers or vetch for 5 years and intercropped by spontaneous herbaceous vegetation in the sixth year. The PA land use is 5 years of spontaneous herbaceous vegetation, and one year of intercropping with oats, Italian ryegrass and annual clovers or vetch cultivated as a hay crop. The SN land use (scrublands, Mediterranean maquis and Helichrysum meadows) arise from the natural re-vegetation of former vineyards which have been set-aside probably due to the low grape yields and the high cost of modern tillage equipment. Both PA and HC are grazed for some months during the year, and include scattered cork-oak trees, which are key components of the 'Dehesa'-type landscape (grazing system with Quercus L.) typical of this area of Sardinia and other areas of southern Mediterranean Europe. Dehesas are often converted to more profitable land uses such as vineyards (Francaviglia et al., 2012; Mu

  8. Soil-gas phase transport and structure parameters for soils under different management regimes and at two moisture levels

    DEFF Research Database (Denmark)

    Eden, Marie; Møldrup, Per; Schjønning, Per

    2012-01-01

    Measurements of diffusive and convective gas transport parameters can be used to describe soil functional architecture and reveal key factors for soil structure development. Undisturbed 100-cm(3) soil samples were sampled at the Long-term Research on Agricultural Systems experiment located...... displayed markedly lower D-P/D-0 values at similar air-filled porosity, illustrating soil structure effects on D-P/D-0. The Currie tortuosity-connectivity parameter, X=Log(D-P/D-0)/Log(epsilon), decreased with increasing bulk density in the intact samples at both moisture conditions, suggesting less...

  9. Determination of soil erosion risk in the Mustafakemalpasa River Basin, Turkey, using the revised universal soil loss equation, geographic information system, and remote sensing.

    Science.gov (United States)

    Ozsoy, Gokhan; Aksoy, Ertugrul; Dirim, M Sabri; Tumsavas, Zeynal

    2012-10-01

    Sediment transport from steep slopes and agricultural lands into the Uluabat Lake (a RAMSAR site) by the Mustafakemalpasa (MKP) River is a serious problem within the river basin. Predictive erosion models are useful tools for evaluating soil erosion and establishing soil erosion management plans. The Revised Universal Soil Loss Equation (RUSLE) function is a commonly used erosion model for this purpose in Turkey and the rest of the world. This research integrates the RUSLE within a geographic information system environment to investigate the spatial distribution of annual soil loss potential in the MKP River Basin. The rainfall erosivity factor was developed from local annual precipitation data using a modified Fournier index: The topographic factor was developed from a digital elevation model; the K factor was determined from a combination of the soil map and the geological map; and the land cover factor was generated from Landsat-7 Enhanced Thematic Mapper (ETM) images. According to the model, the total soil loss potential of the MKP River Basin from erosion by water was 11,296,063 Mg year(-1) with an average soil loss of 11.2 Mg year(-1). The RUSLE produces only local erosion values and cannot be used to estimate the sediment yield for a watershed. To estimate the sediment yield, sediment-delivery ratio equations were used and compared with the sediment-monitoring reports of the Dolluk stream gauging station on the MKP River, which collected data for >41 years (1964-2005). This station observes the overall efficiency of the sediment yield coming from the Orhaneli and Emet Rivers. The measured sediment in the Emet and Orhaneli sub-basins is 1,082,010 Mg year(-1) and was estimated to be 1,640,947 Mg year(-1) for the same two sub-basins. The measured sediment yield of the gauge station is 127.6 Mg km(-2) year(-1) but was estimated to be 170.2 Mg km(-2) year(-1). The close match between the sediment amounts estimated using the RUSLE

  10. Carbon storage of different soil-size fractions in Florida silvopastoral systems.

    Science.gov (United States)

    Haile, Solomon G; Nair, P K Ramachandran; Nair, Vimala D

    2008-01-01

    Compared with open (treeless) pasture systems, silvopastoral agroforestry systems that integrate trees into pasture production systems are likely to enhance soil carbon (C) sequestration in deeper soil layers. To test this hypothesis, total soil C contents at six soil depths (0-5, 5-15, 15-30, 30-50, 50-75, and 75-125 cm) were determined in silvopastoral systems with slash pine (Pinus elliottii) + bahiagrass (Paspalum notatum) and an adjacent open pasture (OP) with bahiagrass at four sites, representing Spodosols and Ultisols, in Florida. Soil samples from each layer were fractionated into three classes (250-2000, 53-250, and <53 microm), and the C contents in each were determined. Averaged across four sites and all depths, the total soil organic carbon (SOC) content was higher by 33% in silvopastures near trees (SP-T) and by 28% in the alleys between tree rows (SP-A) than in adjacent open pastures. It was higher by 39% in SP-A and 20% in SP-T than in open pastures in the largest fraction size (250-2000 microm) and by 12.3 and 18.8%, respectively, in the intermediate size fraction (53-250 microm). The highest SOC increase (up to 45 kg m(-2)) in whole soil of silvopasture compared with OP was at the 75- to 125-cm depth at the Spodosol sites. The results support the hypothesis that, compared with open pastures, silvopastures contain more C in deeper soil layers under similar ecological settings, possibly as a consequence of a major input to soil organic matter from decomposition of dead tree-roots.

  11. Soil-based filtration technology for air purification: potentials for environmental and space life support application

    Science.gov (United States)

    Nelson, Mark; Bohn, Hinrich

    Soil biofiltration, also known as Soil bed reactor (SBR), technology was originally developed in Germany to take advantage of the diversity in microbial mechanisms to control gases producing malodor in industrial processes. The approach has since gained wider international acceptance and seen numerous improvements, for example, by the use of high-organic compost beds to maximize microbial processes. This paper reviews the basic mechanisms which underlay soil processes involved in air purification, advantages and limitations of the technology and the cur-rent research status of the approach. Soil biofiltration has lower capital and operating/energetic costs than conventional technologies and is well adapted to handle contaminants in moderate concentrations. The systems can be engineered to optimize efficiency though manipulation of temperature, pH, moisture content, soil organic matter and airflow rates. SBR technology was modified for application in the Biosphere 2 project, which demonstrated in preparatory research with a number of closed system testbeds that soil could also support crop plants while also serving as soil filters with air pumps to push air through the soil. This Biosphere 2 research demonstrated in several closed system testbeds that a number of important trace gases could be kept under control and led to the engineering of the entire agricultural soil of Biosphere 2 to serve as a soil filtration unit for the facility. Soil biofiltration, coupled with food crop produc-tion, as a component of bioregenerative space life support systems has the advantages of lower energy use and avoidance of the consumables required for other air purification approaches. Expanding use of soil biofiltration can aid a number of environmental applications, from the mitigation of indoor air pollution, improvement of industrial air emissions and prevention of accidental release of toxic gases.

  12. Leaching of soils during laboratory incubations does not affect soil organic carbon mineralisation but solubilisation.

    Science.gov (United States)

    González-Domínguez, Beatriz; Studer, Mirjam S; Hagedorn, Frank; Niklaus, Pascal A; Abiven, Samuel

    2017-01-01

    Laboratory soil incubations provide controlled conditions to investigate carbon and nutrient dynamics; however, they are not free of artefacts. As carbon and nitrogen cycles are tightly linked, we aimed at investigating whether the incubation-induced accumulation of mineral nitrogen (Nmin) biases soil organic carbon (SOC) mineralisation. For this, we selected two soils representative of the C:N ratio values found in European temperate forests, and applied two incubation systems: 'closed' beakers and 'open' microlysimeters. The latter allowed leaching the soil samples during the incubation. By the end of the 121-day experiment, the low C:N soil significantly accumulated more Nmin in beakers (5.12 g kg-1 OC) than in microlysimeters (3.00 g kg-1 OC) but there was not a significant difference in SOC mineralisation at any point of the experiment. On the other hand, Nmin did not accumulate in the high C:N soil but, by the end of the experiment, leaching had promoted 33.9% more SOC solubilisation than beakers. Therefore, we did not find evidence that incubation experiments introduce a bias on SOC mineralisation. This outcome strengthens results from soil incubation studies.

  13. Pedoinformatics Approach to Soil Text Analytics

    Science.gov (United States)

    Furey, J.; Seiter, J.; Davis, A.

    2017-12-01

    The several extant schema for the classification of soils rely on differing criteria, but the major soil science taxonomies, including the United States Department of Agriculture (USDA) and the international harmonized World Reference Base for Soil Resources systems, are based principally on inferred pedogenic properties. These taxonomies largely result from compiled individual observations of soil morphologies within soil profiles, and the vast majority of this pedologic information is contained in qualitative text descriptions. We present text mining analyses of hundreds of gigabytes of parsed text and other data in the digitally available USDA soil taxonomy documentation, the Soil Survey Geographic (SSURGO) database, and the National Cooperative Soil Survey (NCSS) soil characterization database. These analyses implemented iPython calls to Gensim modules for topic modelling, with latent semantic indexing completed down to the lowest taxon level (soil series) paragraphs. Via a custom extension of the Natural Language Toolkit (NLTK), approximately one percent of the USDA soil series descriptions were used to train a classifier for the remainder of the documents, essentially by treating soil science words as comprising a novel language. While location-specific descriptors at the soil series level are amenable to geomatics methods, unsupervised clustering of the occurrence of other soil science words did not closely follow the usual hierarchy of soil taxa. We present preliminary phrasal analyses that may account for some of these effects.

  14. Migration of 137Cs and 90Sr in undisturbed soil profiles under controlled and close-to-real conditions

    International Nuclear Information System (INIS)

    Forsberg, S.; Rosen, K.; Fernandez, V.; Juhan, H.

    2000-01-01

    Migration of 137 Cs and 90 Sr in undisturbed soil was studied in large lysimeters three and four years after contamination, as part of a larger European project studying radionuclide soil-plant interactions. The lysimeters were installed in greenhouses with climate control and contaminated with radionuclides in an aerosol mixture, simulating fallout from a nuclear accident. The soil types studied were loam, silt loam, sandy loam and loamy sand. The soils were sampled to 30-40 cm depth in 1997 and 1998. The total deposition of 137 Cs ranged from 24 to 45 MBq/m 2 , and of 90 Sr from 23 to 52 MBq/m 2 . It was shown that migration of 137 Cs was fastest in sandy loam, and of 90 Sr fastest in sandy loam and loam. The slowest migration of both nuclides was found in loamy sand. Retention within the upper 5 cm was 60% for both 137 Cs and 90 Sr in sandy loam, while in loamy sand it was 97 and 96%, respectively. In 1998, migration rates, calculated as radionuclide weighted median depth (migration centre) divided by time since deposition were 1.1 cm/year for both 137 Cs and 90 Sr in sandy loam, 0.8 and 1.0 cm/year, respectively, in loam, 0.6 and 0.8 cm/year in silt loam, and 0.4 and 0.6 cm/year for 137 Cs and 90 Sr, respectively, in loamy sand. A distinction is made between short-term migration, caused by events soon after deposition and less affected by soil type, and long-term migration, more affected by e.g. soil texture. Three to four years after deposition, effects of short-term migration is still dominant in the studied soils

  15. Relationship Between Soil Characteristics and Rate of Soil Loss on Coffee Base-Farming System at Sumberjaya, West Lampung

    OpenAIRE

    DARIAH, AI; AGUS, F; ARSYAD, S; SUDARSONO,; MASWAR,

    2003-01-01

    The current public perception concerning land use change is, whenever forest is converted to agricultural land, the forest functions would drasticaly decrease. Studies have shown that soil loss in coffee based systems varied widely and it could be much lower than the tolerable soil loss level, depending on soil properties. This research was conducted to determine the dominant factors of soil properties in influencing soil loss. This analysis was based on data collected from a 3-site (Laksana,...

  16. Bioavailability and ecotoxicity of arsenic species in solution culture and soil system: implications to remediation.

    Science.gov (United States)

    Bolan, Nanthi; Mahimairaja, Santiago; Kunhikrishnan, Anitha; Seshadri, Balaji; Thangarajan, Ramya

    2015-06-01

    In this work, bioavailability and ecotoxicity of arsenite (As(III)) and arsenate (As(V)) species were compared between solution culture and soil system. Firstly, the adsorption of As(III) and As(V) was compared using a number of non-allophanic and allophanic soils. Secondly, the bioavailability and ecotoxicity were examined using germination, phytoavailability, earthworm, and soil microbial activity tests. Both As-spiked soils and As-contaminated sheep dip soils were used to test bioavailability and ecotoxicity. The sheep dip soil which contained predominantly As(V) species was subject to flooding to reduce As(V) to As(III) and then used along with the control treatment soil to compare the bioavailability between As species. Adsorption of As(V) was much higher than that of As(III), and the difference in adsorption between these two species was more pronounced in the allophanic than non-allophanic soils. In the solution culture, there was no significant difference in bioavailability and ecotoxicity, as measured by germination and phytoavailability tests, between these two As species. Whereas in the As-spiked soils, the bioavailability and ecotoxicity were higher for As(III) than As(V), and the difference was more pronounced in the allophanic than non-allophanic soils. Bioavailability of As increased with the flooding of the sheep dip soils which may be attributed to the reduction of As(V) to As(III) species. The results in this study have demonstrated that while in solution, the bioavailability and ecotoxicity do not vary between As(III) and As(V), in soils, the latter species is less bioavailable than the former species because As(V) is more strongly retained than As(III). Since the bioavailability and ecotoxicity of As depend on the nature of As species present in the environment, risk-based remediation approach should aim at controlling the dynamics of As transformation.

  17. The Frequency and Damping of Soil-Structure Systems with Embedded Foundation

    International Nuclear Information System (INIS)

    Ghannad, M. Ali; Rahmani, Mohammad T.; Jahankhah, Hossein

    2008-01-01

    The effect of foundation embedment on fundamental period and damping of buildings has been the title of several researches in three past decades. A review of the literature reveals some discrepancies between proposed formulations for dynamic characteristics of soil-embedded foundation-structure systems that raise the necessity of more investigation on this issue. Here, first a set of approximate polynomial equations for soil impedances, based on numerical data calculated from well known cone models, are presented. Then a simplified approach is suggested to calculate period and damping of the whole system considering soil medium as a viscoelastic half space. The procedure includes both material and radiation damping while frequency dependency of soil impedance functions is not ignored. Results show that soil-structure interaction can highly affect dynamic properties of system. Finally the results are compared with one of the commonly referred researches

  18. Water table fluctuations and soil biogeochemistry: An experimental approach using an automated soil column system

    Science.gov (United States)

    Rezanezhad, F.; Couture, R.-M.; Kovac, R.; O'Connell, D.; Van Cappellen, P.

    2014-02-01

    Water table fluctuations significantly affect the biological and geochemical functioning of soils. Here, we introduce an automated soil column system in which the water table regime is imposed using a computer-controlled, multi-channel pump connected to a hydrostatic equilibrium reservoir and a water storage reservoir. The potential of this new system is illustrated by comparing results from two columns filled with 45 cm of the same homogenized riparian soil. In one soil column the water table remained constant at -20 cm below the soil surface, while in the other the water table oscillated between the soil surface and the bottom of the column, at a rate of 4.8 cm d-1. The experiment ran for 75 days at room temperature (25 ± 2 °C). Micro-sensors installed at -10 and -30 cm below the soil surface in the stable water table column recorded constant redox potentials on the order of 600 and -200 mV, respectively. In the fluctuating water table column, redox potentials at the same depths oscillated between oxidizing (∼700 mV) and reducing (∼-100 mV) conditions. Pore waters collected periodically and solid-phase analyses on core material obtained at the end of the experiment highlighted striking geochemical differences between the two columns, especially in the time series and depth distributions of Fe, Mn, K, P and S. Soil CO2 emissions derived from headspace gas analysis exhibited periodic variations in the fluctuating water table column, with peak values during water table drawdown. Transient redox conditions caused by the water table fluctuations enhanced microbial oxidation of soil organic matter, resulting in a pronounced depletion of particulate organic carbon in the midsection of the fluctuating water table column. Denaturing Gradient Gel Electrophoresis (DGGE) revealed the onset of differentiation of the bacterial communities in the upper (oxidizing) and lower (reducing) soil sections, although no systematic differences in microbial community structure

  19. Soil fertility characteristics as affected by close spacing of conilon coffee plants Características da fertilidade do solo influenciadas pelo plantio adensado de café conilon

    Directory of Open Access Journals (Sweden)

    André Guarçoni M.

    2011-08-01

    Full Text Available In arabica coffee crops grown at high altitudes with lower temperatures, soil fertility can be improved by condensed spacing. However, at low lands with warmer temperatures in which conilon coffee is grown, the effect of close spacing on the soil characteristics may change. Aiming to determine the effect of coffee-trees close planting grown with or without NPK fertilization on the soil fertility characteristics, soil samples were collected (0-20 and 20-40 cm depth within four different conilon crop spacings (2,222; 3,333; 4,000; and 5,000 plants/ha. It was determined pH, H+Al, effective CEC (t, pH 7.0 CEC (T, base saturation (v, aluminum saturation (m values and organic matter (OM, P, K, Ca2+, Mg2+ and Al3+ contents. The analytical results were compared by Student t test and regression analysis. Conilon coffee-trees with close planting only changed soil fertility characteristics when coffee plants received annual NPK fertilization. Close planting substantially increased P and K contents and the T value in the upper soil layer and P and K contents and T, t and H+Al values in the lower soil layer.O plantio adensado melhora a fertilidade do solo em lavouras de café arábica, cultura típica de regiões altas e de temperaturas amenas. O café conilon é cultivado em regiões baixas e quentes, o que pode modificar os efeitos do adensamento sobre a fertilidade do solo. Visando determinar a influência do adensamento de plantio do café conilon, com ou sem adubação, nas características da fertilidade do solo, foram coletadas amostras de solo (0-20 e 20-40 cm de profundidade em quatro densidades de plantio (2.222; 3.333; 4.000 e 5.000 plantas/ha. Foram determinados os valores de pH, H+Al, CTC efetiva (t, CTC pH 7,0 (T, saturação por bases (V e saturação por alumínio (m e os teores de matéria orgânica (MO, P, K, Ca2+, Mg2+ e Al3+. Os resultados analíticos foram comparados pelo teste t de Student e por análise de regressão. O adensamento de

  20. Earthquake response analyses of soil-structure system considering kinematic interaction

    International Nuclear Information System (INIS)

    Murakami, H.; Yokono, K.; Miura, S.; Ishii, K.

    1985-01-01

    Improvement of soil-structure interaction analysis has been one of major concerns in earthquake engineering field, especially in nuclear industries, to evaluate the safety of structure accurately under earthquake events. This research aims to develop a rational analytical tool which considers effect of the 'kinematic interaction' satisfactory with a proposed simple low-pass filter. In this paper, first the effect of the kinematic interaction is investigated based on earthquake response analysis of a reactor building using the practical design models: the spring-mass-dashpot system and the 'lattice model', in which a building and soil medium are modeled by a system of lumped masses. Next, the filter is developed based on parametrical studies with various sizes of depth and width of foundations embedded in two-layers soil, which represents more general soil condition in practical designs compared with a homogeneous soil medium. (orig.)

  1. Soil physico-hydrical properties resulting from the management in Integrated Production Systems

    Directory of Open Access Journals (Sweden)

    André Carlos Auler

    Full Text Available Anthropic action, such as the soil use and management systems, promote changes in the soil structure. These changes might hamper the development of plants in soil management practices that involve its mobilization, and the negative effects might be increased due to intensive use. The aim of this study was to evaluate the physico-hydrical properties of a Haplohumox in integrated production systems under different soil managements. The soil superficial (0.0-0.10 m and sub-superficial (0.10-0.20 m layers were evaluated in the different systems: conventional tillage (CT, minimum tillage (MT, no-tillage (NT and chiseled no-tillage (CNT, taking into consideration the annual ryegrass cropped for different uses [cover crop (C, grazing (G and silage (S] during the winter. Soil bulk density (Db, total porosity (TP, macro (Ma and microporosity (Mi, water retention curves (SWRC and water retention due to pore size (r were determined. The annual ryegrass used as C produced lower Db and Mi and higher TP and Ma in CT, MT and CNT systems. No difference was verified between G and S in any of the management systems or soil layers. The superficial layer SWRC presented similar behavior regarding CT, MT and CNT. Under NT, C resulted in higher water retention. However, G and S provided higher water retention due to the pore size in this system.

  2. Pilot investigations of surface parts of three closed landfills and factors affecting them.

    Science.gov (United States)

    Saarela, Jouko

    2003-05-01

    Aftercare of closed sanitary landfills in a major environmental problem. Rehabilitation of the landfill with vegetation and reducing leachate production are two issues that must be dealt. For this reason, Finnish Environment Institute has conducted several projects on closed landfills. This research aims at determining the physical and chemical properties of the soils at three closed landfills in Helsinki, Finland. Research was conducted to understand the impact by studying the following properties: Chemical, nutrient metal, gamma and radon analysis of surface soils of three closed landfills in Helsinki area.

  3. Mulching as a strategy to improve soil properties and reduce soil erodibility in coffee farming systems of Rwanda

    NARCIS (Netherlands)

    Nzeyimana, I.; Hartemink, A.E.; Ritsema, C.J.; Stroosnijder, L.; Huerta Lwanga, Esperanza; Geissen, V.

    2017-01-01

    In Rwanda, mulch is applied in coffee fields to control soil erosion. The objective of this paper is to quantify the effects of different types of mulch on soil properties and soil erodibility in coffee farming systems in three different agro-ecological zones of the highlands of Rwanda. The

  4. An alternative soil nailing system for slope stabilization: Akarpiles

    Science.gov (United States)

    Lim, Chun-Lan; Chan, Chee-Ming

    2017-11-01

    This research proposes an innovative solution for slope stabilization with less environmental footprint: AKARPILES. In Malaysia, landslide has become common civil and environmental problems that cause impacts to the economy, safety and environment. Therefore, effective slope stabilization method helps to improve the safety of public and protect the environment. This study focused on stabilizing surfacial slope failure. The idea of AKARPILES was generated from the tree roots system in slope stabilization. After the piles are installed in the slope and intercepting the slip plane, grout was pumped in and discharged through holes on the piles. The grout then filled the pores in the soil with random flow within the slip zone. SKW mixture was used to simulate the soil slope. There were two designs being proposed in this study and the prototypes were produced by a 3D printer. Trial mix of the grout was carried out to obtain the optimum mixing ratio of bentonite: cement: water. A series of tests were conducted on the single-pile-reinforced slope under vertical slope crest loading condition considering different slope gradients and nail designs. Parameters such as ultimate load, failure time and failure strain were recorded and compared. As comparison with the unreinforced slope, both designs of AKARPILES showed better but different performances in the model tests.

  5. Soil physical properties on Venezuelan steeplands: Applications to soil conservation planning

    International Nuclear Information System (INIS)

    Delgado, F.

    2004-01-01

    This paper presents a framework to support decision making for soil conservation on Venezuelan steeplands. The general approach is based on the evaluation of two important land qualities: soil productivity and soil erosion risk, both closely related to soil physical properties. Soil productivity can be estimated from soil characteristics such as soil air-water relationships, soil impedances and soil fertility. On the other hand, soil erosion risk depends basically on soil hydrologic properties, rainfall aggressiveness and terrain slope. Two indexes are obtained from soil and land characteristics: soil productivity index (PI) and erosion risk index (ERI), each one evaluates the respective land quality. Subsequently, a matrix with these two qualities shows different land classes as well as soil conservation priorities, conservation requirements and proposed land uses. The paper shows also some applications of the soil productivity index as an approach to evaluate soil loss tolerance for soil conservation programs on tropical steeplands. (author)

  6. Stability performance and interface shear strength of geocomposite drain/soil systems

    Science.gov (United States)

    Othman, Maidiana; Frost, Matthew; Dixon, Neil

    2018-02-01

    Landfill covers are designed as impermeable caps on top of waste containment facilities after the completion of landfill operations. Geocomposite drain (GD) materials consist of a geonet or geospacer (as a drainage core) sandwiched between non-woven geotextiles that act as separators and filters. GD provides a drainage function as part of the cover system. The stability performance of landfill cover system is largely controlled by the interface shear strength mobilized between the elements of the cover. If a GD is used, the interface shear strength properties between the upper surface of the GD and the overlying soil may govern stability of the system. It is not uncommon for fine grained materials to be used as cover soils. In these cases, understanding soil softening issues at the soil interface with the non-woven geotextile is important. Such softening can be caused by capillary break behaviour and build-up of water pressures from the toe of the drain upwards into the cover soil. The interaction processes to allow water flow into a GD core through the soil-geotextile interface is very complex. This paper reports the main behaviour of in-situ interface shear strength of soil-GD using field measurements on the trial landfill cover at Bletchley, UK. The soil softening at the interface due to soaked behaviour show a reduction in interface shear strength and this aspect should be emphasized in design specifications and construction control. The results also help to increase confidence in the understanding of the implications for design of cover systems.

  7. Simulation of Tillage Systems Impact on Soil Biophysical Properties Using the SALUS Model

    Directory of Open Access Journals (Sweden)

    Luigi Sartori

    2011-02-01

    Full Text Available A sustainable land management has been defined as the management system that allows for production, while minimizing risk, maintaining quality of soil and water. Tillage systems can significantly decrease soil carbon storage and influence the soil environment of a crop. Crop growth models can be useful tools in evaluating the impact of different tillage systems on soil biophysical properties and on the growth and final yield of the crops. The objectives of this paper were i to illustrate the SALUS model and its tillage component; ii to evaluate the effects of different tillage systems on water infiltration and time to ponding, iii to simulate the effect of tillage systems on some soil biophysical properties. The SALUS (System Approach to Land Use Sustainability model is designed to simulate continuous crop, soil, water and nutrient conditions under different tillage and crop residues management strategies for multiple years. Predictions of changes in surface residue, bulk density, runoff, drainage and evaporation were consistent with expected behaviours of these parameters as described in the literature. The experiment to estimate the time to ponding curve under different tillage system confirmed the theory and showed the beneficial effects of the residue on soil surface with respect to water infiltration. It also showed that the no-tillage system is a more appropriate system to adopt in areas characterized by high intensity rainfall.

  8. Simulation of Tillage Systems Impact on Soil Biophysical Properties Using the SALUS Model

    Directory of Open Access Journals (Sweden)

    Bruno Basso

    2006-12-01

    Full Text Available A sustainable land management has been defined as the management system that allows for production, while minimizing risk, maintaining quality of soil and water. Tillage systems can significantly decrease soil carbon storage and influence the soil environment of a crop. Crop growth models can be useful tools in evaluating the impact of different tillage systems on soil biophysical properties and on the growth and final yield of the crops. The objectives of this paper were i to illustrate the SALUS model and its tillage component; ii to evaluate the effects of different tillage systems on water infiltration and time to ponding, iii to simulate the effect of tillage systems on some soil biophysical properties. The SALUS (System Approach to Land Use Sustainability model is designed to simulate continuous crop, soil, water and nutrient conditions under different tillage and crop residues management strategies for multiple years. Predictions of changes in surface residue, bulk density, runoff, drainage and evaporation were consistent with expected behaviours of these parameters as described in the literature. The experiment to estimate the time to ponding curve under different tillage system confirmed the theory and showed the beneficial effects of the residue on soil surface with respect to water infiltration. It also showed that the no-tillage system is a more appropriate system to adopt in areas characterized by high intensity rainfall.

  9. Soils in Lower Saxony. Pt. 1. Soil properties, soil use and soil protection. NIBIS - Lower Saxony Soil Information System. Information system on soil science; Boeden in Niedersachsen. T. 1. Bodeneigenschaften, Bodennutzung und Bodenschutz. Niedersaechsiches Bodeninformationssystem NIBIS. Fachinformationssystem Bodenkunde

    Energy Technology Data Exchange (ETDEWEB)

    Benzler, J.H.; Boess, J.; Capelle, A.; Gehrt, E.; Heineke, H.J.; Kues, J.; Mueller, U.; Oelkers, K.H.; Roeschmann, G.; Schneider, J.; Sponagel, H. [Niedersaechsisches Landesamt fuer Bodenforschung, Hannover (Germany). Abt. Bodenkunde

    1997-12-31

    In the first part the multitude of activities in Lower Saxony on soil information are described, in particular the structure of the NIBIS (Niedersaechsisches Bodeninformationssystem - Lower Saxony Soil Information System) and the wide range of possibilities for its usage. The second part is meant to enhance the interest in and the knowledge about soils. The history of land use and the great structural variety of soils in Lower Saxony, the complex associations and their distribution are presented in cross sections, profiles and maps. A detailed bibliography provides information about the relevant literature. (orig.) [Deutsch] Im ersten Teil werden die vielfaeltigen Aktivitaeten in Niedersachsen auf dem Gebiet der Bodeninformation verdeutlicht. Insbesondere werden der Aufbau des Niedersaechsischen Informationssystems NIBIS und seine Nutzungsmoeglichkeiten dargestellt. Im zweiten Kapitel soll das Verstaendnis fuer das Medium Boden geweckt werden. Die Geschichte der Bodennutzung sowie die Vielfalt des Aufbaues der Boeden Niedersachsens, die Komplexibilitaet ihrer Vergesellschaftung und die Vorstellungen zur Bodenverbreitung werden mit Gelaendeschnitten, Profilaufnahmen und Karten vorgestellt. Ein ausfuehrliches Literaturverzeichnis verweist auf weiterfuehrende Schriften. (orig.)

  10. Seasonal Soil Nitrogen Mineralization within an Integrated Crop and Livestock System in Western North Dakota, USA

    Science.gov (United States)

    Landblom, Douglas; Senturklu, Songul; Cihacek, Larry; Pfenning, Lauren; Brevik, Eric C.

    2015-04-01

    pipes were pressed into the soil as enclosures to restrict root access to soil nitrogen. Soil samples were taken as close to 2-week intervals as possible from both inside and outside the enclosures. The crop rotation N values were also compared to triple replicated perennial native grassland plot areas (predominate sp. Western wheatgrass - Pascopyrum smithii, Blue grama - Bouteloua gracilis, Little bluestem - Schizachyrium scoparium, Switchgrass - Panicum virgatum). Trends identified for both NH4-N and NO3-N indicate that the values are relatively similar with respect to seasonal change over time. There was a greater amount of soil nitrogen accumulation inside the enclosures indicating that outside the enclosures roots scavenge nitrogen for plant growth and production. Seasonally, comparing the cropping system crops, NO3-N declined mid-July and then rebounded by mid-August and continued to increase until leveling off in September. Corn NO3-N, however, did not follow this pattern, but increased from early June to the end of June and remained high until the first of September. We will present the results of bulk density data and seasonal N fertility data providing evidence for the impact of previous CC on corn production. Probable explanation for the mid-summer nitrogen decline will be presented and justification for reduced fertilizer application will be discussed.

  11. Chemical and structural characterization of soil humic substances under agroforestry and conventional systems

    Directory of Open Access Journals (Sweden)

    Gislane M. de Moraes

    2011-10-01

    Full Text Available Studies have proven that the agroforestry systems in the semi-arid region of the State of Ceará, Brazil, induce an increase in soil organic C levels. Notwithstanding, there is no information if this increase also results in qualitative changes in different pools of soil organic matter. The objective of this study was to verify the possible chemical and structural alterations in fulvic and humic acids of a Luvisol in areas adopting agroforestry, traditional intensive cultivation and native forest in a long-term experiment conducted in the semi-arid region of Ceará State, Brazil. The study was conducted in an experimental area of the National Goat Research Center (Embrapa in Sobral, CE. The following treatments were evaluated: agrosilvopasture (AGP, silvopasture (SILV, intensive cultivation under fallow (ICF, and areas with native forest (NF. Soil fulvic and humic acids fractions were extracted from the 0-6 and 6-12 cm layers and characterized by elemental composition, thermogravimetry and infrared spectroscopy analyses. The elemental composition analysis of humic acids confirmed the data found for fulvic acids, showing reduction in the C, H and N levels, followed by an increase in O contents in the AGP and ICF treatments over SILV and NF. In all treatments, except to SILV in the 0-6 cm layer, the percentage of mass loss was highest (300-600 °C for humic acids in the thermally most stable region. Despite the similarity between infrared spectra, soil fulvic acids in the SILV treatment extracted from 6-12 cm depth decrease the absorption bands at 1708 and 1408 cm-1 followed by an increase in the absorption band at 1608 cm-1 attributed to aromatic C=C groups. This behavior suggests an increase in the aromatic character of the structure. The AGP and ICF treatments, which increase the soil tilling, favored the maintenance of humic substances with a more aromatic character in the soil than SILV and NF. The less aromatic humic substances in the SILV

  12. Influence of management and environment on Australian wheat: information for sustainable intensification and closing yield gaps

    Science.gov (United States)

    Bryan, B. A.; King, D.; Zhao, G.

    2014-04-01

    In the future, agriculture will need to produce more, from less land, more sustainably. But currently, in many places, actual crop yields are below those attainable. We quantified the ability for agricultural management to increase wheat yields across 179 Mha of potentially arable land in Australia. Using the Agricultural Production Systems Simulator (APSIM), we simulated the impact on wheat yield of 225 fertilization and residue management scenarios at a high spatial, temporal, and agronomic resolution from 1900 to 2010. The influence of management and environmental variables on wheat yield was then assessed using Spearman’s non-parametric correlation test with bootstrapping. While residue management showed little correlation, fertilization strongly increased wheat yield up to around 100 kg N ha-1 yr-1. However, this effect was highly dependent on the key environment variables of rainfall, temperature, and soil water holding capacity. The influence of fertilization on yield was stronger in cooler, wetter climates, and in soils with greater water holding capacity. We conclude that the effectiveness of management intensification to increase wheat yield is highly dependent upon local climate and soil conditions. We provide context-specific information on the yield benefits of fertilization to support adaptive agronomic decision-making and contribute to the closure of yield gaps. We also suggest that future assessments consider the economic and environmental sustainability of management intensification for closing yield gaps.

  13. Soil food web properties explain ecosystem services across European land use systems.

    Science.gov (United States)

    de Vries, Franciska T; Thébault, Elisa; Liiri, Mira; Birkhofer, Klaus; Tsiafouli, Maria A; Bjørnlund, Lisa; Bracht Jørgensen, Helene; Brady, Mark Vincent; Christensen, Søren; de Ruiter, Peter C; d'Hertefeldt, Tina; Frouz, Jan; Hedlund, Katarina; Hemerik, Lia; Hol, W H Gera; Hotes, Stefan; Mortimer, Simon R; Setälä, Heikki; Sgardelis, Stefanos P; Uteseny, Karoline; van der Putten, Wim H; Wolters, Volkmar; Bardgett, Richard D

    2013-08-27

    Intensive land use reduces the diversity and abundance of many soil biota, with consequences for the processes that they govern and the ecosystem services that these processes underpin. Relationships between soil biota and ecosystem processes have mostly been found in laboratory experiments and rarely are found in the field. Here, we quantified, across four countries of contrasting climatic and soil conditions in Europe, how differences in soil food web composition resulting from land use systems (intensive wheat rotation, extensive rotation, and permanent grassland) influence the functioning of soils and the ecosystem services that they deliver. Intensive wheat rotation consistently reduced the biomass of all components of the soil food web across all countries. Soil food web properties strongly and consistently predicted processes of C and N cycling across land use systems and geographic locations, and they were a better predictor of these processes than land use. Processes of carbon loss increased with soil food web properties that correlated with soil C content, such as earthworm biomass and fungal/bacterial energy channel ratio, and were greatest in permanent grassland. In contrast, processes of N cycling were explained by soil food web properties independent of land use, such as arbuscular mycorrhizal fungi and bacterial channel biomass. Our quantification of the contribution of soil organisms to processes of C and N cycling across land use systems and geographic locations shows that soil biota need to be included in C and N cycling models and highlights the need to map and conserve soil biodiversity across the world.

  14. A review of control strategies in closed-loop neuroprosthetic systems

    Directory of Open Access Journals (Sweden)

    James Wright

    2016-07-01

    Full Text Available It has been widely recognized that closed-loop neuroprosthetic systems achieve more favorable outcomes for users then equivalent open-loop devices. Improved performance of tasks, better usability and greater embodiment have all been reported in systems utilizing some form of feedback. However the interdisciplinary work on neuroprosthetic systems can lead to miscommunication due to similarities in well established nomenclature in different fields. Here we present a review of control strategies in existing experimental, investigational and clinical neuroprosthetic systems in order to establish a baseline and promote a common understanding of different feedback modes and closed-loop controllers. The first section provides a brief discussion of feedback control and control theory. The second section reviews the control strategies of recent Brain Machine Interfaces, neuromodulatory implants, neuroprosthetic systems and assistive neurorobotic devices. The final section examines the different approaches to feedback in current neuroprosthetic and neurorobotic systems.

  15. Bioelectric potentials in the soil-plant system

    Science.gov (United States)

    Pozdnyakov, A. I.

    2013-07-01

    A detailed study of the electric potentials in the soil-plant system was performed. It was found that the electric potential depends on the plant species and the soil properties. A theoretical interpretation of the obtained data was given. All the plants, independently from their species and their state, always had a negative electric potential relative to the soil. The electric potential of the herbaceous plants largely depended on the leaf area. In some plants, such as burdock ( Arctium lappa) and hogweed ( Heracleum sosnowskyi), the absolute values of the negative electric potential exceeded 100 mV. The electric potential was clearly differentiated by the plant organs: in the flowers, it was lower than in the leaves; in the leaves, it was usually lower than in the leaf rosettes and stems. The electric potentials displayed seasonal dynamics. As a rule, the higher the soil water content, the lower the electric potential of the plants. However, an inverse relationship was observed for dandelions ( Taraxacum officinale). It can be supposed that the electric potential between the soil and the plant characterizes the vital energy of the plant.

  16. Soil Characteristics Driving Arbuscular Mycorrhizal Fungal Communities in Semiarid Mediterranean Soils.

    Science.gov (United States)

    Alguacil, Maria Del Mar; Torres, Maria Pilar; Montesinos-Navarro, Alicia; Roldán, Antonio

    2016-06-01

    We investigated communities of arbuscular mycorrhizal fungi (AMF) in the roots and the rhizosphere soil of Brachypodium retusum in six different natural soils under field conditions. We explored phylogenetic patterns of AMF composition using indicator species analyses to find AMF associated with a given habitat (root versus rhizosphere) or soil type. We tested whether the AMF characteristics of different habitats or contrasting soils were more closely related than expected by chance. Then we used principal-component analysis and multivariate analysis of variance to test for the relative contribution of each factor in explaining the variation in fungal community composition. Finally, we used redundancy analysis to identify the soil properties that significantly explained the differences in AMF communities across soil types. The results pointed out a tendency of AMF communities in roots to be closely related and different from those in the rhizosphere soil. The indicator species analyses revealed AMF associated with rhizosphere soil and the root habitat. Soil type also determined the distribution of AMF communities in soils, and this effect could not be attributed to a single soil characteristic, as at least three soil properties related to microbial activity, i.e., pH and levels of two micronutrients (Mn and Zn), played significant roles in triggering AMF populations. Communities of arbuscular mycorrhizal fungi (AMF) are main components of soil biota that can determine the productivity of ecosystems. These fungal assemblages vary across host plants and ecosystems, but the main ecological processes that shape the structures of these communities are still largely unknown. A field study in six different soil types from semiarid areas revealed that AMF communities are significantly influenced by habitat (soil versus roots) and soil type. In addition, three soil properties related to microbiological activity (i.e., pH and manganese and zinc levels) were the main factors

  17. Soil Characteristics Driving Arbuscular Mycorrhizal Fungal Communities in Semiarid Mediterranean Soils

    Science.gov (United States)

    Torres, Maria Pilar; Montesinos-Navarro, Alicia; Roldán, Antonio

    2016-01-01

    ABSTRACT We investigated communities of arbuscular mycorrhizal fungi (AMF) in the roots and the rhizosphere soil of Brachypodium retusum in six different natural soils under field conditions. We explored phylogenetic patterns of AMF composition using indicator species analyses to find AMF associated with a given habitat (root versus rhizosphere) or soil type. We tested whether the AMF characteristics of different habitats or contrasting soils were more closely related than expected by chance. Then we used principal-component analysis and multivariate analysis of variance to test for the relative contribution of each factor in explaining the variation in fungal community composition. Finally, we used redundancy analysis to identify the soil properties that significantly explained the differences in AMF communities across soil types. The results pointed out a tendency of AMF communities in roots to be closely related and different from those in the rhizosphere soil. The indicator species analyses revealed AMF associated with rhizosphere soil and the root habitat. Soil type also determined the distribution of AMF communities in soils, and this effect could not be attributed to a single soil characteristic, as at least three soil properties related to microbial activity, i.e., pH and levels of two micronutrients (Mn and Zn), played significant roles in triggering AMF populations. IMPORTANCE Communities of arbuscular mycorrhizal fungi (AMF) are main components of soil biota that can determine the productivity of ecosystems. These fungal assemblages vary across host plants and ecosystems, but the main ecological processes that shape the structures of these communities are still largely unknown. A field study in six different soil types from semiarid areas revealed that AMF communities are significantly influenced by habitat (soil versus roots) and soil type. In addition, three soil properties related to microbiological activity (i.e., pH and manganese and zinc levels

  18. Closed-Loop Tension Control System for Injection Moulding Machine

    African Journals Online (AJOL)

    When the mould unit is full, this drive keeps transporting filament materials without proper control. This project developed a closed loop feedback tension control system and it is to replace servo motor drive system for the transportation of filament and it demonstrated a new technological advancement and the theory of ...

  19. Design and Fabrication of a Soil Moisture Meter Using Thermal Conductivity Properties of Soil

    Directory of Open Access Journals (Sweden)

    Subir DAS

    2011-09-01

    Full Text Available Study of soil for agricultural purposes is one of the main focuses of research since the beginning of civilization as food related requirements is closely linked with the soil. The study of soil has generated an interest among the researchers for very similar other reasons including understanding of soil water dynamics, evolution of agricultural water stress and validation of soil moisture modeling. In this present work design of a soil moisture measurement meter using thermal conductivity properties of soil has been proposed and experimental results are reported.

  20. EFFECTS OF DIFFERENT SOIL TILLAGE SYSTEMS ON NODULATION AND YIELD OF SOYBEAN

    Directory of Open Access Journals (Sweden)

    D. Jug

    2005-12-01

    Full Text Available The primary soil tillage for different crops in Croatia is generally based on mouldboard ploughing which is the most expensive for crops production. Negative effects due to frequent passes by equipment and machines (deterioration of soil structure, soil compaction, lower biogenity and soil tilth, together with negative economical and energetical costs, can be lowered and avoided by introduction of reduced soil tillage or direct drilling (No-tillage. Accordingly, the main goal of this research was to determine effects of conventional and reduced soil tillage systems on yield components and nodulation ability of nitrogen fixing bacteria in soybean crop. The research was established at chernozem soil type of northern Baranja as monofactorial completely randomized block design in four repetitions. The soil tillage variants were as follows: CT Conventional Tillage (primary soil tillage by moldboard ploughing at 25-30 cm depth, DH Multiple Diskharrowing at 10-15 cm as primary tillage, and NT No-tillage system. Results show significantly lower plant density, mass of 1000 grains and grain yield at variants with reduced soil tillage in both investigation years. However, reduced tillage systems had positive trend on nitrogen-fixing bacteria nodulation, since the highest values of number and mass of nodules per plant were recorded. This research was run during the years 2002 and 2003, the last one extremely droughty, thus it requires continuation.

  1. Soil functional types: surveying the biophysical dimensions of soil security

    Science.gov (United States)

    Cécillon, Lauric; Barré, Pierre

    2015-04-01

    Soil is a natural capital that can deliver key ecosystem services (ES) to humans through the realization of a series of soil processes controlling ecosystem functioning. Soil is also a diverse and endangered natural resource. A huge pedodiversity has been described at all scales, which is strongly altered by global change. The multidimensional concept soil security, encompassing biophysical, economic, social, policy and legal frameworks of soils has recently been proposed, recognizing the role of soils in global environmental sustainability challenges. The biophysical dimensions of soil security focus on the functionality of a given soil that can be viewed as the combination of its capability and its condition [1]. Indeed, all soils are not equal in term of functionality. They show different processes, provide different ES to humans and respond specifically to global change. Knowledge of soil functionality in space and time is thus a crucial step towards the achievement soil security. All soil classification systems incorporate some functional information, but soil taxonomy alone cannot fully describe the functioning, limitations, resistance and resilience of soils. Droogers and Bouma [2] introduced functional variants (phenoforms) for each soil type (genoform) so as to fit more closely to soil functionality. However, different genoforms can have the same functionality. As stated by McBratney and colleagues [1], there is a great need of an agreed methodology for defining the reference state of soil functionality. Here, we propose soil functional types (SFT) as a relevant classification system for the biophysical dimensions of soil security. Following the definition of plant functional types widely used in ecology, we define a soil functional type as "a set of soil taxons or phenoforms sharing similar processes (e.g. soil respiration), similar effects on ecosystem functioning (e.g. primary productivity) and similar responses to global change (land-use, management or

  2. Soil management in rainfed olive orchards may result in conflicting effects on olive production and soil fertility

    Directory of Open Access Journals (Sweden)

    I. Q. Ferreira

    2013-03-01

    Full Text Available The adoption of a sustainable soil management system is essential for the steep slopes and low fertility soils still supporting rainfed olive orchards in the Mediterranean basin. The effect of the soil management on olive yield, tree nutritional status and soil fertility was studied in a rainfed olive orchard located in NE Portugal that had been managed since its earliest days as a sheep-walk. In 2001, three different soil management systems were established: Sheep-walk, in which the vegetation was managed with a flock of sheep; Tillage, where the vegetation was controlled by conventional tillage; and Glyphosate, where a glyphosate-based herbicide was applied. The soil management systems had a pronounced effect on olive yield. The accumulated olive yields between 2002 and 2011 were 187.2, 142.9 and 89.5 kg tree-1, respectively in the Glyphosate, Tillage and Sheep-walk treatments. However, the effect of soil management on tree nutritional status was not so clear. On the other hand, the pools of organic carbon and N in the soil, and also the soil available N and phosphorus (P, were found to be less in the Glyphosate and Tillage treatments in comparison with the Sheep-walk. In these soils, N appeared as a much more limiting factor for crop growth than P. In rainfed orchards, the tolerance to herbaceous vegetation appears to be a determining factor in sustainability, which regulates annual crop yields and soil fertility. The higher the tolerance to herbaceous species, the lower the olive yields, but the better are the soil fertility parameters.

  3. Closing the nutrient loops in (peri) urban farming systems through composting

    DEFF Research Database (Denmark)

    Nigatu, Abebe Nigussie

    waste management practices in developing countries and ensure sustainable crop production via the biotransformation of urban waste into a high-quality soil amendment. First, I aimed at determining the causes for the limited use of organic amendments in small-scale urban farming systems. I interviewed...... 220 urban farmers in Ethiopia and found that competition for agricultural waste between fuel, feed and soil amendment is a major cause for the limited use of organic amendments. I demonstrated that allocation of agricultural waste for soil amendment is linked with farmers’ livelihood strategies. I...... also studied variation in compost demand among different farmer groups, and the socio-economic variables which explained these variations. Gaseous losses of ammonia and greenhouse gas (GHG) emissions occur during composting of nitrogen-rich urban waste. Several technologies could reduce these losses...

  4. Determining Threshold Distance Providing Less Interference for Wireless Medical Implant Communication Systems in Coexisting Environments under Shadow Fading Conditions

    Directory of Open Access Journals (Sweden)

    Selman KULAÇ

    2017-08-01

    Full Text Available Important interference problems will be able to be encountered especially close areas to the hospitals where wireless implantable medical systems' communication traffic occurs heavily in near future. It is possible that these interferences could cause wireless implant devices to malfunction and harmful effects on patients. In this study, it is proposed to determine threshold distance in order to get less interference for wireless implantable medical systems under shadow fading conditions where MICS band and MetAids band users coexist intensely simultaneously. In this method, threshold power according to the \\cite{FCC} is pulled down by adding extra distance margin in order to minimize the interference effects to the MICS systems using confidence interval calculations. Because received signal strength just below the monitoring threshold power according to the \\cite{FCC} brings about much more interferences for the MICS systems even if listen-before-talk technique is applied.

  5. Application of soil washing system to the volume reduction of radioactively contaminated soils and automated treatment of sludge cake

    International Nuclear Information System (INIS)

    Mouri, Mitsuo; Tsuchida, Mitsuru; Baba, Naoki; Nakajima, Takuma

    2013-01-01

    The pilot plant study was intended to evaluate; a) the removal efficiency of radioactive Cs, b) the volume reduction rate of feed soils, c) the volumetric rate and concentration rate of discharged sludge cake, and d) the effect of radiation exposure reduction by automated filter press unit and automated packing unit of sludge cake. As a result of this study, following observations were made; 1) the radioactive Cs content of clean sands ranged 882∼2,940 Bq/kg as compared to the feed soils of 8,790 to 26,270 Bq/kg, 2) the removal efficiency of radioactive Cs ranged 84∼92% of feed soils, 3) the volume reduction rate of feed soils ranged 70∼86% (ave. 82%), and 4) the automated filter press unit and the automated packing system of sludge cake were helpful for workers in reducing radiation exposure. It is concluded that soil washing system can effectively reduce volume of radioactively contaminated soils and can be practically used in Fukushima for remediation of soils. (author)

  6. Greenhouse gas fluxes from agricultural soils under organic and non-organic management — A global meta-analysis

    International Nuclear Information System (INIS)

    Skinner, Colin; Gattinger, Andreas; Muller, Adrian; Mäder, Paul; Fließbach, Andreas; Stolze, Matthias; Ruser, Reiner; Niggli, Urs

    2014-01-01

    It is anticipated that organic farming systems provide benefits concerning soil conservation and climate protection. A literature search on measured soil-derived greenhouse gas (GHG) (nitrous oxide and methane) fluxes under organic and non-organic management from farming system comparisons was conducted and followed by a meta-analysis. Up to date only 19 studies based on field measurements could be retrieved. Based on 12 studies that cover annual measurements, it appeared with a high significance that area-scaled nitrous oxide emissions from organically managed soils are 492 ± 160 kg CO 2 eq. ha −1 a −1 lower than from non-organically managed soils. For arable soils the difference amounts to 497 ± 162 kg CO 2 eq. ha −1 a −1 . However, yield-scaled nitrous oxide emissions are higher by 41 ± 34 kg CO 2 eq. t −1 DM under organic management (arable and use). To equalize this mean difference in yield-scaled nitrous oxide emissions between both farming systems, the yield gap has to be less than 17%. Emissions from conventionally managed soils seemed to be influenced mainly by total N inputs, whereas for organically managed soils other variables such as soil characteristics seemed to be more important. This can be explained by the higher bioavailability of the synthetic N fertilisers in non-organic farming systems while the necessary mineralisation of the N sources under organic management leads to lower and retarded availability. Furthermore, a higher methane uptake of 3.2 ± 2.5 kg CO 2 eq. ha −1 a −1 for arable soils under organic management can be observed. Only one comparative study on rice paddies has been published up to date. All 19 retrieved studies were conducted in the Northern hemisphere under temperate climate. Further GHG flux measurements in farming system comparisons are required to confirm the results and close the existing knowledge gaps. - Highlights: • Lower area-scaled nitrous oxide emissions from soils managed organically compared

  7. Interactions in Natural Colloid Systems "Biosolids" - Soil and Plant

    Science.gov (United States)

    Kalinichenko, Kira V.; Nikovskaya, Galina N.; Ulberg, Zoya R.

    2016-04-01

    The "biosolids" are complex biocolloid system arising in huge amounts (mln tons per year) from biological municipal wastewater treatment. These contain clusters of nanoparticles of heavy metal compounds (in slightly soluble or unsoluble forms, such as phosphates, sulphates, carbonates, hydroxides, and etc.), cells, humic substances and so on, involved in exopolysaccharides (EPS) net matrix. One may consider that biosolids are the natural nanocomposite. Due to the presence of nitrogen, phosphorus, potassium and other macro- and microelements (heavy metals), vitamins, aminoacids, etc., the biosolids are a depot of bioelements for plant nutrition. Thus, it is generally recognized that most rationally to utilize them for land application. For this purpose the biocolloid process was developed in biosolids system by initiation of microbial vital ability followed by the synthesis of EPS, propagation of ecologically important microorganisms, loosening of the structure and weakening of the coagulation contacts between biosolids colloids, but the structure integrity maintaining [1,2]. It was demonstrated that the applying of biosolids with metabolizing microorganisms to soil provided the improving soil structure, namely the increasing of waterstable aggregates content (70% vs. 20%). It occurs due to flocculation ability of biosolids EPS. The experimental modelling of mutual interactions in systems of soils - biosolids (with metabolizing microorganisms) were realized and their colloid and chemical mechanisms were formulated [3]. As it is known, the most harmonious plant growth comes at a prolonged entering of nutrients under the action of plant roots exudates which include pool of organic acids and polysaccharides [4]. Special investigations showed that under the influence of exudates excreted by growing plants, the biosolids microelements can release gradually from immobilized state into environment and are able to absorb by plants. Thus, the biosolids can serve as an active

  8. Development of standard practice guidelines for open and closed system suctioning.

    Science.gov (United States)

    Özden, Dilek; Görgülü, R Selma

    2012-05-01

    This study was carried out to determine the knowledge and practice of nurses before and after training and the development of standard practice guidelines for open and closed system suctioning methods in patients with endotracheal tubes. Many life-threatening complications can occur when a suctioning procedure is not performed with the correct technique. It has been reported that standard practice guidelines for suctioning are insufficient in clinical practice. Non-participant structured observational study. We assessed a total of 48 nurses who were employed in the cardiovascular surgery intensive care unit of a state hospital in Turkey. We used a questionnaire and nurse observation forms to assess the use of the open and closed system suctioning. There was a significant difference between the mean scores of the answers ('true', 'wrong' and 'I do not know') for the use of open and closed system suctioning before and after training. In addition, all steps of both suctioning procedures were carried out correctly during the third observation. The compliance of the nurses to the standard practice guidelines for open and closed suctioning and their knowledge levels on the subject were increased after training, while the implementation of standards was satisfactory. The development of open and closed system suctioning standard practice guidelines directly contributed to the enhancement of patient safety and the quality of nursing care. It is suggested that, as in other nursing care practices, suctioning should be carried out in accordance with standard practice guidelines, and health institutions should develop their standard practice guidelines and work in accordance with them. © 2012 Blackwell Publishing Ltd.

  9. Detector design for active fault diagnosis in closed-loop systems

    DEFF Research Database (Denmark)

    Sekunda, André Krabdrup; Niemann, Hans Henrik; Poulsen, Niels Kjølstad

    2018-01-01

    Fault diagnosis of closed-loop systems is extremely relevant for high-precision equipment and safety critical systems. Fault diagnosis is usually divided into 2 schemes: active and passive fault diagnosis. Recent studies have highlighted some advantages of active fault diagnosis based on dual Youla......-Jabr-Bongiorno-Kucera parameters. In this paper, a method for closed-loop active fault diagnosis based on statistical detectors is given using dual Youla-Jabr-Bongiorno-Kucera parameters. The goal of this paper is 2-fold. First, the authors introduce a method for measuring a residual signal subject to white noise. Second...

  10. Closed system for bovine oocyte vitrification

    Directory of Open Access Journals (Sweden)

    Helena Ševelová

    2012-01-01

    Full Text Available The aim of our study was to develop a vitrification carrier for bovine oocyte cryopreservation. The carrier was to be cheap enough, elementary in its construction and meet contemporary requirements for a safe closed system. In a closed system, a cell is prevented from direct exposure to liquid nitrogen, thus minimizing the risk of cross-contamination. Furthermore, two questions regarding the proper vitrification technique were resolved: if it is necessary to partially denude the oocytes before the vitrification process or whether intact cumulus oocyte complexes should be frozen; and if it is more advantageous to preheat the vitrification solutions to female body temperature (39 °C or to keep them at room temperature. Our results show that it is better to partially denude the oocytes prior to vitrification because cryopreserved intact cumulus oocyte complexes often proved dark, non-homogeneous or fragmented cytoplasm after warming, with many of them having visibly widened perivitelline spaces or fractured zonae pellucidae as a result of extensive damage during vitrification. Consequently, intact cumulus oocyte complexes showed significantly lower numbers of cleavage stage embryos on Day 3 compared to partially denuded oocytes (7.4% and 26%, respectively. On the other hand, the survival rate and following development of fertilized oocytes in preheated vitrification solution were equal to results reached at room temperature conditions. In conclusion, results achieved with the newly developed carrier were comparable to previously published studies and therefore they could be recommended for common use.

  11. Cs phytoremediation by Sorghum bicolor cultivated in soil and in hydroponic system.

    Science.gov (United States)

    Wang, Xu; Chen, Can; Wang, Jianlong

    2017-04-03

    Cs accumulation characteristics by Sorghum bicolor were investigated in hydroponic system (Cs level at 50-1000 μmol/L) and in soil (Cs-spiked concentration was 100 and 400 mg/kg soil). Two varieties of S. bicolor Cowly and Nengsi 2# grown on pot soil during the entire growth period (100 days) did not show significant differences on the height, dry weight (DW), and Cs accumulation. S. bicolor showed the potential phytoextraction ability for Cs-contaminated soil with the bioaccumulation factor (BCF) and the translocation factor (TF) values usually higher than 1 in soil system and in hydroponic system. The aerial parts of S. bicolor contributed to 86-92% of the total removed amounts of Cs from soil. Cs level in solution at 100 μmol/L gave the highest BCF and TF values of S. bicolor. Cs at low level tended to transfer to the aerial parts, whereas Cs at high level decreased the transfer ratio from root to shoot. In soil, the plant grew well when Cs spiked level was 100 mg/kg soil, but was inhibited by Cs at 400 mg/kg soil with Cs content in sorghum reaching 1147 mg/kg (roots), 2473 mg/kg (stems), and 2939 mg/kg (leaves). In hydroponic system, average Cs level in sorghum reached 5270 mg/kg (roots) and 4513 mg/kg (aerial parts), without significant damages to its biomass at 30 days after starting Cs treatment. Cs accumulation in sorghum tissues was positively correlated with the metal concentration in medium.

  12. Soil physical properties and grape yield influenced by cover crops and management systems

    Directory of Open Access Journals (Sweden)

    Jaqueline Dalla Rosa

    2013-10-01

    Full Text Available The use of cover crops in vineyards is a conservation practice with the purpose of reducing soil erosion and improving the soil physical quality. The objective of this study was to evaluate cover crop species and management systems on soil physical properties and grape yield. The experiment was carried out in Bento Gonçalves, RS, Southern Brazil, on a Haplic Cambisol, in a vineyard established in 1989, using White and Rose Niagara grape (Vitis labrusca L. in a horizontal, overhead trellis system. The treatments were established in 2002, consisting of three cover crops: spontaneous species (SS, black oat (Avena strigosa Schreb (BO, and a mixture of white clover (Trifolium repens L., red clover (Trifolium pratense L. and annual rye-grass (Lolium multiflorum L. (MC. Two management systems were applied: desiccation with herbicide (D and mechanical mowing (M. Soil under a native forest (NF area was collected as a reference. The experimental design consisted of completely randomized blocks, with three replications. The soil physical properties in the vine rows were not influenced by cover crops and were similar to the native forest, with good quality of the soil structure. In the inter-rows, however, there was a reduction in biopores, macroporosity, total porosity and an increase in soil density, related to the compaction of the surface soil layer. The M system increased soil aggregate stability compared to the D system. The treatments affected grapevine yield only in years with excess or irregular rainfall.

  13. Soil organic carbon sequestration and tillage systems in Mediterranean environments

    Science.gov (United States)

    Francaviglia, Rosa; Di Bene, Claudia; Marchetti, Alessandro; Farina, Roberta

    2016-04-01

    Soil carbon sequestration is of special interest in Mediterranean areas, where rainfed cropping systems are prevalent, inputs of organic matter to soils are low and mostly rely on crop residues, while losses are high due to climatic and anthropic factors such as intensive and non-conservative farming practices. The adoption of reduced or no tillage systems, characterized by a lower soil disturbance in comparison with conventional tillage, has proved to be positively effective on soil organic carbon (SOC) conservation and other physical and chemical processes, parameters or functions, e.g. erosion, compaction, ion retention and exchange, buffering capacity, water retention and aggregate stability. Moreover, soil biological and biochemical processes are usually improved by the reduction of tillage intensity. The work deals with some results available in the scientific literature, and related to field experiment on arable crops performed in Italy, Greece, Morocco and Spain. Data were organized in a dataset containing the main environmental parameters (altitude, temperature, rainfall), soil tillage system information (conventional, minimum and no-tillage), soil parameters (bulk density, pH, particle size distribution and texture), crop type, rotation, management and length of the experiment in years, initial SOCi and final SOCf stocks. Sampling sites are located between 33° 00' and 43° 32' latitude N, 2-860 m a.s.l., with mean annual temperature and rainfall in the range 10.9-19.6° C and 355-900 mm. SOC data, expressed in t C ha-1, have been evaluated both in terms of Carbon Sequestration Rate, given by [(SOCf-SOCi)/length in years], and as percentage change in comparison with the initial value [(SOCf-SOCi)/SOCi*100]. Data variability due to the different environmental, soil and crop management conditions that influence SOC sequestration and losses will be examined.

  14. Measurements of trace contaminants in closed-type plant cultivation chambers

    Science.gov (United States)

    Tani, A.; Kiyota, M.; Aiga, I.; Nitta, K.; Tako, Y.; Ashida, A.; Otsubo, K.; Saito, T.

    Trace contaminants generated in closed facilities can cause abnormal plant growth. We present measurement data of trace contaminants released from soils, plants, and construction materials. We mainly used two closed chambers, a Closed-type Plant and Mushroom Cultivation Chamber (PMCC) and Closed-type Plant Cultivation Equipment (CPCE). Although trace gas budgets from soils obtained in this experiment are only one example, the results indicate that the budgets of trace gases, as well as CO_2 and O_2, change greatly with the degree of soil maturation and are dependent on the kind of substances in the soil. Both in the PMCC and in the CPCE, trace gases such as dioctyl phthalate (DOP), dibutyl phthalate (DBP), toluene and xylene were detected. These gases seemed to be released from various materials used in the construction of these chambers. The degree of increase in these trace gas levels was dependent on the relationship between chamber capacity and plant quantity. Results of trace gas measurement in the PMCC, in which lettuce and shiitake mushroom were cultivated, showed that ethylene was released both from lettuce and from the mushroom culture bed. The release rates were about 90 ng bed^-1 h^-1 for the shiitake mushroom culture bed (volume is 1700 cm^3) and 4.1 ~ 17.3 ng dm^-2h^-1 (leaf area basis) for lettuce. Higher ethylene release rates per plant and per unit leaf area were observed in mature plants than in young plants.

  15. Urban gray vs. urban green vs. soil protection — Development of a systemic solution to soil sealing management on the example of Germany

    International Nuclear Information System (INIS)

    Artmann, Martina

    2016-01-01

    Managing urban soil sealing is a difficult venture due to its spatial heterogeneity and embedding in a socio-ecological system. A systemic solution is needed to tackle its spatial, ecological and social sub-systems. This study develops a guideline for urban actors to find a systemic solution to soil sealing management based on two case studies in Germany: Munich and Leipzig. Legal-planning, informal-planning, economic-fiscal, co-operative and informational responses were evaluated by indicators to proof which strategy considers the spatial complexity of urban soil sealing (systemic spatial efficiency) and, while considering spatial complexity, to assess what the key management areas for action are to reduce the ecological impacts by urban soil sealing (ecological impact efficiency) and to support an efficient implementation by urban actors (social implementation efficiency). Results suggest framing the systemic solution to soil sealing management through a cross-scale, legal-planning development strategy embedded in higher European policies. Within the socio-ecological system, the key management area for action should focus on the protection of green infrastructure being of high value for actors from the European to local scales. Further efforts are necessary to establish a systemic monitoring concept to optimize socio-ecological benefits and avoid trade-offs such as between urban infill development and urban green protection. This place-based study can be regarded as a stepping stone on how to develop systemic strategies by considering different spatial sub-targets and socio-ecological systems. - Highlights: • Urban soil sealing management is spatially complex. • The legal-planning strategy supports a systemic sealing management. • Urban green infrastructure protection should be in the management focus. • Soil protection requires policies from higher levels of government. • A systemic urban soil sealing monitoring concept is needed.

  16. Urban gray vs. urban green vs. soil protection — Development of a systemic solution to soil sealing management on the example of Germany

    Energy Technology Data Exchange (ETDEWEB)

    Artmann, Martina, E-mail: m.artmann@ioer.de

    2016-07-15

    Managing urban soil sealing is a difficult venture due to its spatial heterogeneity and embedding in a socio-ecological system. A systemic solution is needed to tackle its spatial, ecological and social sub-systems. This study develops a guideline for urban actors to find a systemic solution to soil sealing management based on two case studies in Germany: Munich and Leipzig. Legal-planning, informal-planning, economic-fiscal, co-operative and informational responses were evaluated by indicators to proof which strategy considers the spatial complexity of urban soil sealing (systemic spatial efficiency) and, while considering spatial complexity, to assess what the key management areas for action are to reduce the ecological impacts by urban soil sealing (ecological impact efficiency) and to support an efficient implementation by urban actors (social implementation efficiency). Results suggest framing the systemic solution to soil sealing management through a cross-scale, legal-planning development strategy embedded in higher European policies. Within the socio-ecological system, the key management area for action should focus on the protection of green infrastructure being of high value for actors from the European to local scales. Further efforts are necessary to establish a systemic monitoring concept to optimize socio-ecological benefits and avoid trade-offs such as between urban infill development and urban green protection. This place-based study can be regarded as a stepping stone on how to develop systemic strategies by considering different spatial sub-targets and socio-ecological systems. - Highlights: • Urban soil sealing management is spatially complex. • The legal-planning strategy supports a systemic sealing management. • Urban green infrastructure protection should be in the management focus. • Soil protection requires policies from higher levels of government. • A systemic urban soil sealing monitoring concept is needed.

  17. Soil attributes of a silvopastoral system in Pernambuco Forest Zone

    Directory of Open Access Journals (Sweden)

    Hugo N.B. Lima

    2018-01-01

    Full Text Available This research evaluated soil properties in a silvopastoral system using double rows of tree legumes. Treatments were signalgrass (Brachiaria decumbens in monoculture or in consortium with sabiá (Mimosa caesalpiniifolia or gliricidia (Gliricidia sepium. Treatments were arranged in a complete randomized block design, with 4 replications. Response variables included chemical characteristics and physical attributes of the soil. Silvopastoral systems had greater (P<0.001 soil exchangeable Ca (gliricidia = 3.2 and sabiá = 3.0 mmolc/dm3 than signalgrass monoculture (2.0 mmolc/dm3. Water infiltration rate was greater within the tree legume double rows (366 mm/h than in signalgrass (162 mm/h (P = 0.02. However, soil moisture was greater in signalgrass pastures (15.9% (P = 0.0020 than in silvopastures (14.9 and 14.8%, where soil moisture levels increased as distance from the tree rows increased. Conversely, the light fraction of soil organic matter was greater within the tree legume double rows than in the grassed area (P = 0.0019. Long-term studies are needed to determine if these benefits accumulate further and the productivity benefits which result.

  18. Soil quality assessment of rice production systems in South of Brazil

    OpenAIRE

    Rodrigues de Lima, A.C.; Hoogmoed, W.B.; Brussaard, L.

    2006-01-01

    Soil quality, as a measure of the soil capacity to function, can be quantified by indicators based on physical, chemical and biological properties. Maintaining soil quality at a desirable level in the rice cropping system is a very complex issue due to the nature of the production systems used. In the state of Rio Grande do Sul, Brazil, rice production is one of the most important agricultural activities in the region. The study presented here was conducted with the following objectives: (i) ...

  19. In-situ remediation system for groundwater and soils

    Science.gov (United States)

    Corey, John C.; Kaback, Dawn S.; Looney, Brian B.

    1993-01-01

    A method and system for in-situ remediation of contaminated groundwater and soil where the contaminants, such as toxic metals, are carried in a subsurface plume. The method comprises selection and injection into the soil of a fluid that will cause the contaminants to form stable, non-toxic compounds either directly by combining with the contaminants or indirectly by creating conditions in the soil or changing the conditions of the soil so that the formation of stable, non-toxic compounds between the contaminants and existing substances in the soil are more favorable. In the case of non-toxic metal contaminants, sulfides or sulfates are injected so that metal sulfides or sulfates are formed. Alternatively, an inert gas may be injected to stimulate microorganisms in the soil to produce sulfides which, in turn, react with the metal contaminants. Preferably, two wells are used, one to inject the fluid and one to extract the unused portion of the fluid. The two wells work in combination to create a flow of the fluid across the plume to achieve better, more rapid mixing of the fluid and the contaminants.

  20. Cover crops and crop residue management under no-till systems improve soils and environmental quality

    Science.gov (United States)

    Kumar, Sandeep; Wegner, Brianna; Vahyala, Ibrahim; Osborne, Shannon; Schumacher, Thomas; Lehman, Michael

    2015-04-01

    Crop residue harvest is a common practice in the Midwestern USA for the ethanol production. However, excessive removal of crop residues from the soil surface contributes to the degradation of important soil quality indicators such as soil organic carbon (SOC). Addition of a cover crop may help to mitigate these negative effects. The present study was set up to assess the impacts of corn (Zea mays L.) residue removal and cover crops on various soil quality indicators and surface greenhouse gas (GHG) fluxes. The study was being conducted on plots located at the North Central Agricultural Research Laboratory (NCARL) in Brookings, South Dakota, USA. Three plots of a corn and soybean (Glycine max (L.) Merr.) rotation under a no-till (NT) system are being monitored for soils and surface gas fluxes. Each plot has three residue removal (high residue removal, HRR; medium residue removal, MRR; and low residue removal, LRR) treatments and two cover crops (cover crops and no cover crops) treatments. Both corn and soybean are represented every year. Gas flux measurements were taken weekly using a closed static chamber method. Data show that residue removal significantly impacted soil quality indicators while more time was needed for an affect from cover crop treatments to be noticed. The LRR treatment resulted in higher SOC concentrations, increased aggregate stability, and increased microbial activity. The LRR treatment also increased soil organic matter (SOM) and particulate organic matter (POM) concentrations. Cover crops used in HRR (high corn residue removal) improved SOC (27 g kg-1) by 6% compared to that without cover crops (25.4 g kg-1). Cover crops significantly impacted POM concentration directly after the residue removal treatments were applied in 2012. CO2 fluxes were observed to increase as temperature increased, while N2O fluxes increased as soil moisture increased. CH4 fluxes were responsive to both increases in temperature and moisture. On average, soils under

  1. Degradation of 14C-lindane in soils of planting ginseng

    International Nuclear Information System (INIS)

    Wang Zhengguo; Zhao Jing; Yao Jianren

    1992-01-01

    14 C-Lindane was used to study degradation of Lindane (γ-BHC) in different types of soil of planting ginseng. Results indicated that Lindane was very slowly mineralized after a 228 day's incubation period in closed system. It took about 9 years to completely mineralize Lindane in the chernozem, and 11 years in the brown calcareous at 20 ppm in the soils. In addition, the rate of Lindane mineralized depended on population and number of microorganism. In this test the fungi played more important role than the bacteria in the Lindane mineralization. 14 C-Lindane residues extracted from the soils were 77.43%-80.54%, and Lindane residues associated with the soils were 13.11%-20.77%

  2. Fate of Carbofuran and Interaction with Agricultural Chemicals in a Soil-Crop-Water System

    International Nuclear Information System (INIS)

    Koeppe, M.; Lichtenstein, E.P.

    1981-01-01

    Full text: The fate, movement, and metabolism of 14 C-(ring)-carbofuran and its interaction with agricultural chemicals was studied in a soil-corn-water system. Movement of carbofuran through soils occurred under both percolating and non-percolating conditions. Under percolating conditions 49.13% of applied 14 C leached through the soil into the aquaria. Thus, less 14 C-residues were recovered from percolated soils than from nonpercolated soils, 25.85 and 57.90% of applied C, respectively. The control corn contained more than twice as much 14 C-residues as the corn grown under percolating conditions, 22.16 and 10.78% of applied C, respectively. 14 C-(ring)-carbofuran residues added to aquaria containing a layer of lake mud rapidly disappeared from the water and the majority became bound to the lake mud or was metabolized by the Elodea plants to water-soluble or bound 14 C-residues. After 3 weeks incubation 14 C-residues associated with the water, lake mud, Elodea plants and guppies were 2.14, 19.17, 3.65, and 0.19% of applied 14 C, respectively. Initially, the percolated water containing 14 C-residues was toxic to both guppies and Aedes aegypti Linnaeus larvae. However, guppies and Aedes larvae introduced after 9 days incubation survived for the remainder of the experiment. This indicated that toxic 14 C-residues had either degraded to non-toxic compounds or were no longer associated with the water. (author)

  3. Seasonal dynamics of CO2 efflux in soils amended with composted and thermally-dried sludge as affected by soil tillage systems in a semi-arid agroecosystem

    Science.gov (United States)

    García-Gil, Juan Carlos; Soler-Rovira, Pedro; López-de-Sa, Esther G.; Polo, Alfredo

    2014-05-01

    In semi-arid agricultural soils, seasonal dynamic of soil CO2 efflux (SCE) is highly variable. Based on soil respiration measurements the effects of different management systems (moldboard plowing, chisel and no-tillage) and the application of composted sludge (CS) and thermally-dried sewage sludge (TSS) was investigated in a long-term field experiment (28 years) conducted on a sandy-loam soil at the experimental station 'La Higueruela' (40o 03'N, 4o 24'W). Both organic amendments were applied at a rate of 30 Mg ha-1 prior to tillage practices. Unamended soils were used as control for each tillage system. SCE was moderate in late spring (2.2-11.8 μmol CO2 m-2 s-1) when amendments were applied and tillage was performed, markedly decreased in summer (0.4-3.2 μmol CO2 m-2 s-1), following a moderate increase in autumn (3.4-14.1 μmol CO2 m-2 s-1), rising sharply in October (5.6-39.8 μmol CO2 m-2 s-1 ). In winter, SCE was low (0.6-6.5 μmol CO2 m-2 s-1). In general, SCE was greater in chisel and moldboard tilled soils, and in CS and particularly TSS-amended soils, due to the addition of labile C with these amendments, meanwhile no-tillage soils exhibited smaller increases in C efflux throughout the seasons. Soil temperature controlled the seasonal variations of SCE. In summer, when drought occurs, a general decrease of SCE was observed due to a deficit in soil water content. After drought period SCE jumped to high values in response to rain events ('Birch effect') that changed soil moisture conditions. Soil drying in summer and rewetting in autumn may promotes some changes on the structure of soil microbial community, affecting associated metabolic processes, and enhancing a rapid mineralization of water-soluble organic C compounds and/or dead microbial biomass that acts as an energy source for soil microorganisms. To assess the effects of tillage and amendments on SCE, Q10 values were calculated. Data were grouped into three groups according to soil moisture (0

  4. BIOCHEMICAL PROCESSES IN CHERNOZEM SOIL UNDER DIFFERENT FERTILIZATION SYSTEMS

    Directory of Open Access Journals (Sweden)

    Ecaterina Emnova

    2012-06-01

    Full Text Available The paper deals with the evaluation of the intensity of certain soil biochemical processes (e.g. soil organic C mineralization at Organic and mixed Mineral+Organic fertilization of typical chernozem in crop rotation dynamics (for 6 years by use of eco-physiological indicators of biological soil quality: microbial biomass carbon, basal soil respiration, as well as, microbial and metabolic quotients. Soil sampling was performed from a long-term field crop experiment, which has been established in 1971 at the Balti steppe (Northern Moldova. The crop types had a more considerable impact on the soil microbial biomass accumulation and community biochemical activity compared to long-term Organic or mixed Mineral + Organic fertilizers amendments. The Org fertilization system doesn’t make it possible to avoid the loss of organic C in arable typical chernozem. The organic fertilizer (cattle manure is able to mitigate the negative consequences of long-term mineral fertilization.

  5. Method and apparatus for operating a powertrain system upon detecting a stuck-closed clutch

    Science.gov (United States)

    Hansen, R. Anthony

    2014-02-18

    A powertrain system includes a multi-mode transmission having a plurality of torque machines. A method for controlling the powertrain system includes identifying all presently applied clutches including commanded applied clutches and the stuck-closed clutch upon detecting one of the torque-transfer clutches is in a stuck-closed condition. A closed-loop control system is employed to control operation of the multi-mode transmission accounting for all the presently applied clutches.

  6. Drying/rewetting cycles of the soil under alternate partial root-zone drying irrigation reduce carbon and nitrogen retention in the soil-plant systems of potato

    DEFF Research Database (Denmark)

    Sun, Yanqi; Yan, Fei; Liu, Fulai

    2013-01-01

    for five weeks. For each N rate, the PRD and DI plants received a same amount of water, which allowed re-filling one half of the PRD pots close to full water holding capacity. The results showed that plant dry biomass, plant water use, and water use efficiency were increased with increasing N...... retention in the soil–plant systems of potato. Potato plants were grown in 20 L split-root pots with three N-fertilization rates, viz., 1.4 (N1), 2.5 (N2), and 4 (N3) g N pot−1 soil, respectively. At tuber initiation and earlier tuber bulking stages, the plants were subjected to PRD and DI treatment...

  7. Responses of soil microbial biomass and bacterial community structure to closed-off management (an ecological natural restoration measures): A case study of Dongting Lake wetland, middle China.

    Science.gov (United States)

    Dai, Juan; Wu, Haipeng; Zhang, Chang; Zeng, Guangming; Liang, Jie; Guo, Shenglian; Li, Xiaodong; Huang, Lu; Lu, Lunhui; Yuan, Yujie

    2016-09-01

    Soil microbial biomass (SMB) and bacterial community structure, which are critical to global ecosystem and fundamental ecological processes, are sensitive to anthropogenic activities and environmental conditions. In this study, we examined the possible effects of closed-off management (an ecological natural restoration measures, ban on anthropogenic activity, widely employed for many important wetlands) on SMB, soil bacterial community structure and functional marker genes of nitrogen cycling in Dongting Lake wetland. Soil samples were collected from management area (MA) and contrast area (CA: human activities, such as hunting, fishing and draining, are permitted) in November 2013 and April 2014. Soil properties, microbial biomass carbon (MBC), and bacterial community structure were investigated. Comparison of the values of MA and CA showed that SMB and bacterial community diversity of the MA had a significant increase after 7 years closed-off management. The mean value of Shannon-Weiner diversity index of MA and CA respectively were 2.85 and 2.07. The gene copy numbers of 16S rRNA and nosZ of MA were significant higher than those of CA. the gene copy numbers of ammonia-oxidizing archaea (AOA) and nirK of MA were significant lower than those of CA. However, there was no significant change in the gene copy numbers of ammonia-oxidizing bacteria (AOB) and nirS. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  8. Evaluating litter decomposition and soil organic matter dynamics in earth system models: contrasting analysis of long-term litter decomposition and steady-state soil carbon

    Science.gov (United States)

    Bonan, G. B.; Wieder, W. R.

    2012-12-01

    litterfall and model-derived climatic decomposition index. While comparison with the LIDET 10-year litterbag study reveals sharp contrasts between CLM4 and DAYCENT, simulations of steady-state soil carbon show less difference between models. Both CLM4 and DAYCENT significantly underestimate soil carbon. Sensitivity analyses highlight causes of the low soil carbon bias. The terrestrial biogeochemistry of earth system models must be critically tested with observations, and the consequences of particular model choices must be documented. Long-term litter decomposition experiments such as LIDET provide a real-world process-oriented benchmark to evaluate models and can critically inform model development. Analysis of steady-state soil carbon estimates reveal additional, but here different, inferences about model performance.

  9. Changes in soil carbon cycling accompanying conversion of row-crop fields to grazing dairy pastures

    Science.gov (United States)

    Thompson, A.; Kramer, M. G.; Hill, N.; Machmuller, M. B.; Cyle, K.

    2011-12-01

    Increasingly, the dairy industry in the eastern US is transitioning from total confinement dairy systems (TCD) toward pasture-based, management intensive grazing dairy (MiGD) systems. This transition is driven by the fact that MiGDs require substantially less operating capital and are more economically efficient than TCD systems. Consequently, the impact of this transition and shift in land-use practice on carbon dynamics may be considerable. Land-use in a Management intensive Grazing Dairy (MiGD) system is fundamentally different than conventional confinement dairies and conventional no-till pastures. The forage system involves rotational grazing at optimal digestibility, when the plants are immature (~20-days) and consequently protein-rich. MiGD cows spend >90% of their time in the field and deposit > 90% of their waste directly to the soil surface. Thus, little above ground plant residues are directly returned to the soil, but rather substantial C inputs derive from bovine manure. We sampled a MiGD-chronosequence of row-crop to MiGD conversion established in 2007 in eastern Georgia. All soils across the MiGD-chronosequence, all occur in relative (40 km) close proximity to one another, are deep, well-drained, fine and fine sandy loam Ultisols formed on Coastal Plain sediments. Prior to MiGD established, the soils were farmed for > 50 yrs using conventional tillage techniques. Our current sampling to 1m depths captures fields at 0, 2, 3, and 5 yrs since conversion. Total soil carbon (C) and the carbon concentration of the clay fraction increased following conversion, with the greatest increases occurring between 3 and 5 yrs since conversion. These C increases were limited to the upper 40cm of the soil, with minimal change occurring at depth. Characterization of the protein and ligand content of these soils via 13C NMR and chemolytic techniques as a function of soil particle density and size is in progress and will be presented along with estimates of carbon

  10. Multi criteria evaluation for universal soil loss equation based on geographic information system

    Science.gov (United States)

    Purwaamijaya, I. M.

    2018-05-01

    The purpose of this research were to produce(l) a conceptual, functional model designed and implementation for universal soil loss equation (usle), (2) standard operational procedure for multi criteria evaluation of universal soil loss equation (usle) using geographic information system, (3) overlay land cover, slope, soil and rain fall layers to gain universal soil loss equation (usle) using multi criteria evaluation, (4) thematic map of universal soil loss equation (usle) in watershed, (5) attribute table of universal soil loss equation (usle) in watershed. Descriptive and formal correlation methods are used for this research. Cikapundung Watershed, Bandung, West Java, Indonesia was study location. This research was conducted on January 2016 to May 2016. A spatial analysis is used to superimposed land cover, slope, soil and rain layers become universal soil loss equation (usle). Multi criteria evaluation for universal soil loss equation (usle) using geographic information system could be used for conservation program.

  11. Soil decontamination criteria report, November 1980

    International Nuclear Information System (INIS)

    Riordan, G.A.

    1980-01-01

    A program to access the extent of transuranic soil contamination at DOE sites and to develop methods for their decontamination is underway at Rocky Flats. As part of this program, acceptable soil contamination levels for plutonium proposed by a number of authorities over the past couple of decades were reviewed. From this review, goals for soil decontamination work are proposed. These goals, which relate to the disposition of the products of a decontamination process, are summarized as follows (dpm/g will refer to disintegrations per minute of transuranic nuclides per gram of soil): soil fractions having less than 30 dpm can be disposed of as surface soil with unrestricted usage. Fine soil fractions (less than 100 μm) that have less than 500 dpm and coarse soil fractions that have less than 1000 dpm can be disposed of as subsurface soil as long as usage is controlled to ensure compliance with EPA dosage guidance. Soil concentrates that have an activity greater than the above values but less than 22,000 dpm should be interred in an approved, low level waste burial site. Soil concentrates that are greater than 22,000 dpm should be stored as retrievable waste. Changes in the technical and legal areas of soil decontamination are rapid. Permissible soil decontamination levels will change as will decontamination technology and the ability to monitor the effectiveness of the decontamination processes. As a result, annual updates of decontamination criteria, goals, and monitoring are expected

  12. Modification of the USLE K factor for soil erodibility assessment on calcareous soils in Iran

    Science.gov (United States)

    Ostovari, Yaser; Ghorbani-Dashtaki, Shoja; Bahrami, Hossein-Ali; Naderi, Mehdi; Dematte, Jose Alexandre M.; Kerry, Ruth

    2016-11-01

    The measurement of soil erodibility (K) in the field is tedious, time-consuming and expensive; therefore, its prediction through pedotransfer functions (PTFs) could be far less costly and time-consuming. The aim of this study was to develop new PTFs to estimate the K factor using multiple linear regression, Mamdani fuzzy inference systems, and artificial neural networks. For this purpose, K was measured in 40 erosion plots with natural rainfall. Various soil properties including the soil particle size distribution, calcium carbonate equivalent, organic matter, permeability, and wet-aggregate stability were measured. The results showed that the mean measured K was 0.014 t h MJ- 1 mm- 1 and 2.08 times less than the estimated mean K (0.030 t h MJ- 1 mm- 1) using the USLE model. Permeability, wet-aggregate stability, very fine sand, and calcium carbonate were selected as independent variables by forward stepwise regression in order to assess the ability of multiple linear regression, Mamdani fuzzy inference systems and artificial neural networks to predict K. The calcium carbonate equivalent, which is not accounted for in the USLE model, had a significant impact on K in multiple linear regression due to its strong influence on the stability of aggregates and soil permeability. Statistical indices in validation and calibration datasets determined that the artificial neural networks method with the highest R2, lowest RMSE, and lowest ME was the best model for estimating the K factor. A strong correlation (R2 = 0.81, n = 40, p soils.

  13. Removal of CO2 in closed loop off-gas treatment systems

    International Nuclear Information System (INIS)

    Clemens, M.K.; Nelson, P.A.; Swift, W.M.

    1994-01-01

    A closed loop test system has been installed at Argonne National Laboratory (ANL) to demonstrate off-gas treatment, absorption, and purification systems to be used for incineration and vitrification of hazardous and mixed waste. Closed loop systems can virtually eliminate the potential for release of hazardous or toxic materials to the atmosphere during both normal and upset conditions. In initial tests, a 250,000 Btu/h (75 kW thermal) combustor was operated in an open loop to produce a combustion product gas. The CO 2 in these tests was removed by reaction with a fluidized bed of time to produce CaCO 3 . Subsequently, recirculation system was installed to allow closed loop operation with the addition of oxygen to the recycle stream to support combustion. Commercially marketed technologies for removal of CO 2 can be adapted for use on closed loop incineration systems. The paper also describes the Absorbent Solution Treatment (AST) process, based on modifications to commercially demonstrated gas purification technologies. In this process, a side loop system is added to the main loop for removing CO 2 in scrubbing towers using aqueous-based CO 2 absorbents. The remaining gas is returned to the incinerator with oxygen addition. The absorbent is regenerated by driving off the CO 2 and water vapor, which are released to the atmosphere. Contaminants are either recycled for further treatment or form precipitates which are removed during the purification and regeneration process. There are no direct releases of gases or particulates to the environment. The CO 2 and water vapor go through two changes of state before release, effectively separating these combustion products from contaminants released during incineration. The AST process can accept a wide range of waste streams. The system may be retrofitted to existing Facilities or included in the designs for new installations

  14. Particulate Organic Matter Affects Soil Nitrogen Mineralization under Two Crop Rotation Systems.

    Directory of Open Access Journals (Sweden)

    Rongyan Bu

    Full Text Available Changes in the quantity and/or quality of soil labile organic matter between and after different types of cultivation system could play a dominant role in soil nitrogen (N mineralization. The quantity and quality of particulate organic matter (POM and potentially mineralizable-N (PMN contents were measured in soils from 16 paired rice-rapeseed (RR/cotton-rapeseed (CR rotations sites in Hubei province, central China. Then four paired soils encompassing low (10th percentile, intermediate (25th and 75th percentiles, and high (90th percentile levels of soil PMN were selected to further study the effects of POM on soil N mineralization by quantifying the net N mineralization in original soils and soils from which POM was removed. Both soil POM carbon (POM-C and N (POM-N contents were 45.8% and 55.8% higher under the RR rotation compared to the CR rotation, respectively. The PMN contents were highly correlated with the POM contents. The PMN and microbial biomass N (MBN contents concurrently and significantly decreased when POM was removed. The reduction rate of PMN was positively correlated with changes in MBN after the removal of POM. The reduction rates of PMN and MBN after POM removal are lower under RR rotations (38.0% and 16.3%, respectively than CR rotations (45.6% and 19.5%, respectively. Furthermore, infrared spectroscopy indicated that compounds with low-bioavailability accumulated (e.g., aromatic recalcitrant materials in the soil POM fraction under the RR rotation but not under the CR rotation. The results of the present study demonstrated that POM plays a vital role in soil N mineralization under different rotation systems. The discrepancy between POM content and composition resulting from different crop rotation systems caused differences in N mineralization in soils.

  15. Near-field soil-structure interaction analysis using nonlinear hybrid modeling

    International Nuclear Information System (INIS)

    Katayama, I.; Chen, C.; Lee, Y.J.; Jean, W.Y.; Penzien, J.

    1989-01-01

    The hybrid modeling method (Gupta and Penzien 1980) and associated analysis procedure for solving a three-dimensional soil-structure interaction problem was developed by Gupta and Penzien (1981) and Gupta et al.(1982). Subsequently, successive modifications have been made to the original modeling method and analysis procedure allowing more general treatment of the SSI problem (Penzien, 1988). Through many correlation studies of field test data obtained under forced-vibration and earthquake-excitation conditions, it has been shown that the HASSI programs can effectively predict the dynamic response of a soil-structure system, if realistic soil parameters are adopted. In the above, the entire structure-foundation system is considered to respond in a linear fashion. Since the reflected three-dimensional waves at the soil-structure interface decays very rapidly with distance away from the structure (Katayama, 1987 (a)), the response of the soil close to the base of the structure may greatly affect its response; therefore, proper modeling of the non-linear soil behavior characteristic is essential. The nonlinear behavior of near-field soil has been taken into consideration in HASSI-7 by the standard equivalent linearization procedures used in programs SHAKE and FLUSH

  16. On site experiments of the slanted soil treatment systems for domestic gray water.

    Science.gov (United States)

    Itayama, Tomoaki; Kiji, Masato; Suetsugu, Aya; Tanaka, Nobuyuki; Saito, Takeshi; Iwami, Norio; Mizuochi, Motoyuki; Inamori, Yuhei

    2006-01-01

    In order to make a breakthrough for the acute problem of water shortage in the world, the key words "decentralization and re-use" are very important for new sustainable sanitation systems that will be developed. Therefore, we focused on a new treatments system called "a slanted soil treatment system" which combines a biotoilet system with a domestic grey water treatment system. Because this system is a low cost and compact system, the system can be easily introduced to homes in urban areas or in the suburbs of cities in many developing countries. In this study, we performed on site experiments carried out on Shikoku Island, Japan, for several years. We obtained the following results. The slanted soil treatment system could remove organic pollutants and total nitrogen and total phosphorus in grey water effectively. Furthermore, the system performance became high in the case of the high concentration of the influent water. The nitrification reaction and denitrification reaction were speculated to exist due to aerobic zones and anaerobic zones present in the slanted soil treatment system. The slanted soil treatment system could perform for approximately 3 years with zero maintenance. The plug flow model of 1st order reaction kinetics could describe the reaction in the slanted soil treatment system. However, it is necessary to improve the system to maintain the performance in all seasons.

  17. The Role of Vegetation and Mulch in Mitigating the Impact of Raindrops on Soils in Urban Vegetated Green Infrastructure Systems

    Science.gov (United States)

    Alizadehtazi, B.; Montalto, F. A.; Sjoblom, K.

    2014-12-01

    Raindrop impulses applied to soils can break up larger soil aggregates into smaller particles, dispersing them from their original position. The displaced particles can self-stratify, with finer particles at the top forming a crust. Occurrence of this phenomenon reduces the infiltration rate and increases runoff, contributing to downstream flooding, soil erosion, and non point source pollutant loads. Unprotected soil surfaces (e.g. without vegetation canopies, mulch, or other materials), are more susceptible to crust formation due to the higher kinetic energy associated with raindrop impact. By contrast, soil that is protected by vegetation canopies and mulch layers is less susceptible to crust formation, since these surfaces intercept raindrops, dissipating some of their kinetic energy prior to their impact with the soil. Within this context, this presentation presents preliminary laboratory work conducted using a rainfall simulator to determine the ability of new urban vegetation and mulch to minimize soil crust formation. Three different scenarios are compared: a) bare soil, b) soil with mulch cover, and c) soil protected by vegetation canopies. Soil moisture, surface penetration resistance, and physical measurements of the volume of infiltrate and runoff are made on all three surface treatments after simulated rainfall events. The results are used to develop recommendations regarding surface treatment in green infrastructure (GI) system designs, namely whether heavily vegetated GI facilities require mulching to maintain infiltration capacity.

  18. Rice production in relation to soil quality under different rice-based cropping systems

    Science.gov (United States)

    Tran Ba, Linh; Sleutel, Steven; Nguyen Van, Qui; Thi, Guong Vo; Le Van, Khoa; Cornelis, Wim

    2016-04-01

    Soil quality of shallow paddy soils may be improved by introducing upland crops and thus a more diverse crop cultivation pattern. Yet, the causal relationship between crop performance and enhanced soil traits in rice-upland crop rotations remains elusive. The objectives of this study were to (i) find correlations among soil properties under different rice-upland crop systems and link selected soil properties to rice growth and yield, (ii) present appropriate values of soil parameters for sustainable rice productivity in heavy clay soil, (iii) evaluate the effect of rotating rice with upland crops on rice yield and economic benefit in a long-term experiment. A rice-upland crop rotational field experiment in the Vietnamese Mekong delta was conducted for 10 years using a randomized complete block design with four treatments and four replications. Treatments were: (i) rice-rice-rice (control - conventional system as farmers' practice), (ii) rice-maize-rice, (iii) rice-mung bean-rice, and (iv) rice-mung bean-maize. Soil and plant sampling were performed after harvest of the rice crop at the end of the final winter-spring cropping season (i.e. year 10). Results show differences in rice growth and yield, and economic benefit as an effect of the crop rotation system. These differences were linked with changes in bulk density, soil porosity, soil aggregate stability index, soil penetration resistance, soil macro-porosity, soil organic carbon, acid hydrolysable soil C and soil nutrient elements, especially at soil depth of 20-30 cm. This is evidenced by the strong correlation (P < 0.01) between rice plant parameters, rice yield and soil properties such as bulk density, porosity, penetration resistance, soil organic carbon and Chydrolysable. It turned out that good rice root growth and rice yield corresponded to bulk density values lower than 1.3 Mg m-3, soil porosity higher than 50%, penetration resistance below 1.0 MPa, and soil organic carbon above 25 g kg-1. The optimal

  19. Integrating soil physical and biological properties in contrasting tillage systems in organic and conventional farming

    NARCIS (Netherlands)

    Crittenden, S.J.; Goede, de R.G.M.

    2016-01-01

    Though soil physical and soil biological properties are intrinsically linked in the soil environment they are often studied separately. This work adds value to analyses of soil biophysical quality of tillage systems under organic and conventional farming systems by correlating physical and

  20. Closed soilless growing systems in the Netherlands: the finishing touch

    NARCIS (Netherlands)

    Os, van E.A.

    1998-01-01

    This paper gives an overview of the latest developments in closed soilless growing systems in the Netherlands, where growers are obliged to invest in environmently friendly cropping systems, in order to comply with new legislation. Subjects of discussion will be the reasons for regulation, the

  1. A Transformer-less Single Phase Inverter For photovoltaic Systems

    DEFF Research Database (Denmark)

    Mostaan, Ali; Alizadeh, Ebrahim; Qu, Ying

    2017-01-01

    A single phase transformer-less inverter is introduced in this paper. The negative polarities of the input voltage and output terminal have common ground. Therefore, the leakage current problem that is common in PV systems is eliminated naturally. In addition, the proposed inverter has fewer comp...

  2. Availability of {sup 99}Tc in undisturbed soil cores

    Energy Technology Data Exchange (ETDEWEB)

    Denys, Sebastien; Echevarria, Guillaume E-mail: guillaume.echevarria@ensaia.inpl-nancy.fr; Florentin, Louis; Leclerc-Cessac, Elisabeth; Morel, Jean-Louis

    2003-07-01

    Models for safety assessment of radioactive waste repositories need accurate values of the soil-to-plant transfer of radionuclides. In oxidizing environments, {sup 99}Tc is expected to occur as pertechnetate ({sup 99}TcO{sub 4}{sup -}). Due to its high mobility, leaching of this element in the field might be important, potentially affecting the reliability of estimated transfer parameters of {sup 99}Tc as measured in closed experimental systems such as hydroponics or pot experiments. The aim of this experiment was to measure the leaching of {sup 99}Tc in undisturbed irrigated soil cores under cultivation as well as plant uptake and to study the possible competition between the two transfer pathways. Undisturbed soil cores (50x50 cm) were sampled from a Rendzic Leptosol (R), a colluvial Fluvic Cambisol (F) and a Dystric Cambisol (D) using PVC tubes (three cores sampled per soil type). Each core was equipped with a leachate collector at the bottom, allowing the monitoring of {sup 99}Tc leaching through the cores. Cores were placed in a greenhouse and maize (Zea mays L., cv. DEA, Pioneer[reg]) was sown. After 135 d, maize was harvested and radioactivity determined in both plant and water samples. Results showed that during the growing period, leaching of {sup 99}Tc was limited, due to the high evapotranspiration rate of maize. After harvest, leaching of {sup 99}Tc went on because of the absence of evapotranspiration. Effective uptake (EU) of {sup 99}Tc in leaves and grains was calculated. EU reached 70% of the input in the leaves and was not significantly different among soils. These results confirmed those obtained from pot experiments, even though leaching was allowed to occur in close-to-reality hydraulical conditions. As a consequence, it was concluded that pot experiments are an adequate surrogate for more complex 'close-to-reality' experimental systems for measuring transfer factors.

  3. Potential risk for bacterial contamination in conventional reused ventilator systems and disposable closed ventilator-suction systems.

    Science.gov (United States)

    Li, Ya-Chi; Lin, Hui-Ling; Liao, Fang-Chun; Wang, Sing-Siang; Chang, Hsiu-Chu; Hsu, Hung-Fu; Chen, Sue-Hsien; Wan, Gwo-Hwa

    2018-01-01

    Few studies have investigated the difference in bacterial contamination between conventional reused ventilator systems and disposable closed ventilator-suction systems. The aim of this study was to investigate the bacterial contamination rates of the reused and disposable ventilator systems, and the association between system disconnection and bacterial contamination of ventilator systems. The enrolled intubated and mechanically ventilated patients used a conventional reused ventilator system and a disposable closed ventilator-suction system, respectively, for a week; specimens were then collected from the ventilator circuit systems to evaluate human and environmental bacterial contamination. The sputum specimens from patients were also analyzed in this study. The detection rate of bacteria in the conventional reused ventilator system was substantially higher than that in the disposable ventilator system. The inspiratory and expiratory limbs of the disposable closed ventilator-suction system had higher bacterial concentrations than the conventional reused ventilator system. The bacterial concentration in the heated humidifier of the reused ventilator system was significantly higher than that in the disposable ventilator system. Positive associations existed among the bacterial concentrations at different locations in the reused and disposable ventilator systems, respectively. The predominant bacteria identified in the reused and disposable ventilator systems included Acinetobacter spp., Bacillus cereus, Elizabethkingia spp., Pseudomonas spp., and Stenotrophomonas (Xan) maltophilia. Both the reused and disposable ventilator systems had high bacterial contamination rates after one week of use. Disconnection of the ventilator systems should be avoided during system operation to decrease the risks of environmental pollution and human exposure, especially for the disposable ventilator system. ClinicalTrials.gov PRS / NCT03359148.

  4. A Portable, Low-Power Analyzer and Automated Soil Flux Chamber System for Measuring Wetland GHG Emissions

    Science.gov (United States)

    Nickerson, Nick; Kim-Hak, David; McArthur, Gordon

    2017-04-01

    Preservation and restoration of wetlands has the potential to help sequester large amounts of carbon due to the naturally high primary productivity and slow turnover of stored soil carbon. However, the anoxic environmental conditions present in wetland soils are also the largest natural contributor to global methane emissions. While it is well known that wetlands are net carbon sinks over long time scales, given the high global warming potential of methane, the short-term balances between C uptake and storage and loss as CO2 and CH4 need to be carefully considered when evaluating the climate effects of land-use change. It is relatively difficult to measure methane emissions from wetlands with currently available techniques given the temporally and spatially sporadic nature of the processes involved (methanogenesis, methane oxidation, ebullition, etc.). For example, using manual soil flux chambers can often only capture a portion of either the spatial or temporal variability, and often have other disadvantages associated with soil atmosphere disturbance during deployment in these relatively compressible wetland soils. Automated chamber systems offer the advantage of collecting high-resolution time series of gaseous fluxes while reducing some human and method induced biases. Additionally, new laser-based analyzers that can be used in situ alongside automated chambers offer a greater minimum detectable flux than can be achieved using alternative methods such as Gas Chromatography. Until recently these types of automated measurements were limited to areas that had good power coverage, as laser based systems were power intensive and could not easily be supplemented with power from field-available sources such as solar. Recent advances in laser technology has reduced the power needed and made these systems less power intensive and more field portable in the process. Here we present data using an automated chamber system coupled to a portable laser based greenhouse gas

  5. A multiple soil ecosystem services approach to evaluate the sustainability of reduced tillage systems

    Science.gov (United States)

    Pérès, Guénola; Menasseri, Safya; Hallaire, Vincent; Cluzeau, Daniel; Heddadj, Djilali; Cotinet, Patrice; Manceau, Olivier; Pulleman, Mirjam

    2017-04-01

    In the current context of soil degradation, reduced tillage systems (including reduced soil disturbance, use of cover crops and crop rotation, and improved organic matter management) are expected to be good alternatives to conventional system which have led to a decrease of soil multi-functionality. Many studies worldwide have analysed the impact of tillage systems on different soil functions, but overran integrated view of the impact of these systems is still lacking. The SUSTAIN project (European SNOWMAN programme), performed in France and the Netherlands, proposes an interdisciplinary collaboration. The goals of SUSTAIN are to assess the multi-functionality of soil and to study how reduced-tillage systems impact on multiple ecosystem services such as soil biodiversity regulation (earthworms, nematodes, microorganisms), soil structure maintenance (aggregate stability, compaction, soil erosion), water regulation (run-off, transfer of pesticides) and food production. Moreover, a socio-economic study on farmer networks has been carried out to identify the drivers of adoption of reduced-tillage systems. Data have been collected in long-term experimental fields (5 - 13 years), representing conventional and organic farming strategies, and were complemented with data from farmer networks. The impact of different reduced tillage systems (direct seeding, minimum tillage, non-inverse tillage, superficial ploughing) were analysed and compared to conventional ploughing. Measurements (biological, chemical, physical, agronomical, water and element transfer) have been done at several dates which allow an overview of the evolution of the soil properties according to climate variation and crop rotation. A sociological approach was performed on several farms covering different production types, different courses (engagement in reduced tillage systems) and different geographical locations. Focusing on French trials, this multiple ecosystem services approach clearly showed that

  6. The kinetic model of 137Cs behavior in the system 'soil - plant' accounting of agrochemical soil properties

    International Nuclear Information System (INIS)

    Prister, B.S.; Vinogradskaya, V.D.

    2011-01-01

    From data of the long-term radiological monitoring contaminated after Chernobyl accident lands of Ukraine investigated the dynamics of 137 Cs accumulation by plants in a wide range of environmental conditions. On the basis of modern concepts about the transformation of radionuclides forms in the soil created kinetic model the 137 Cs behavior in the system 'soil - plant', which uses as an argument to a complex estimation of agrochemical properties of soil, calculated according to the triad - the reaction of the soil solution, organic matter content and the amount of absorbed bases. Establish the high accuracy of the model and estimate the possibility of its use for other territories.

  7. Simulated optimization of crop yield through irrigation system design and operation based on the spatial variability of soil hydrodynamic properties

    International Nuclear Information System (INIS)

    Gurovich, L.; Stern, J.; Ramos, R.

    1983-01-01

    Spatial autocorrelation and kriging techniques were applied to soil infiltrability data from a 20 hectare field, to separate homogeneous irrigation units. Border irrigation systems were designed for each unit and combinations of units by using DESIGN, a computer model based on soil infiltrability and hydraulics of surface water flow, which enables optimal irrigation systems to be designed. Water depths effectively infiltrated at different points along the irrigation run were determined, and the agronomic irrigation efficiency of the unit evaluated. A modification of Hanks' evapotranspiration model, PLANTGRO, was used to evaluate plant growth, relative crop yield and soil-water economy throughout the growing season, at several points along each irrigation unit. The effect of different irrigation designs on total field yield and total water used for irrigation was evaluated by integrating yield values corresponding to each point, volume and inflow time during each irrigation. For relevant data from winter wheat grown in the central area of Chile during 1981, simulation by an interactive and sequentially recurrent use of DESIGN and PLANTGRO models, was carried out. The results obtained indicate that, when a field is separated into homogeneous irrigation units on the basis of the spatial variability of soil infiltrability and the border irrigation systems are designed according to soil characteristics, both a significant yield increase and less water use can be obtained by comparison with other criteria of field zonification for irrigation management. The use of neutrometric determinations to assess soil-water content during the growing season, as a validation of the results obtained in this work, is discussed. (author)

  8. Soil quality improvement under an ecologically based farming system in northwest Missouri

    Science.gov (United States)

    Ecologically based farming conserves and improves the soil resource and protects environmental quality by using organic or natural resources without application of synthetic chemicals. Soil quality assessment indicates the ability of management systems to optimize soil productivity and to maintain i...

  9. Climate-smart soils

    Science.gov (United States)

    Paustian, Keith; Lehmann, Johannes; Ogle, Stephen; Reay, David; Robertson, G. Philip; Smith, Pete

    2016-04-01

    Soils are integral to the function of all terrestrial ecosystems and to food and fibre production. An overlooked aspect of soils is their potential to mitigate greenhouse gas emissions. Although proven practices exist, the implementation of soil-based greenhouse gas mitigation activities are at an early stage and accurately quantifying emissions and reductions remains a substantial challenge. Emerging research and information technology developments provide the potential for a broader inclusion of soils in greenhouse gas policies. Here we highlight ‘state of the art’ soil greenhouse gas research, summarize mitigation practices and potentials, identify gaps in data and understanding and suggest ways to close such gaps through new research, technology and collaboration.

  10. Uptake of C-14 tagged acetate by rice in a paddy soil-to-rice plant system

    Energy Technology Data Exchange (ETDEWEB)

    Ishii, Nobuyoshi; Tagami, Keiko; Uchida, Shigeo [Research Center for Radiation Protection, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan)

    2014-07-01

    Geological disposal of Transuranic (TRU) waste is planned to avoid radiation exposure to the public. One of the dominant nuclides contributing to the dose from TRU waste is C-14, which is long-lived and has very poor sorption properties on natural geological media. Therefore, there are some concerns regarding possible migration of C-14 to the living environments. For the public health safety, it is necessary to clarify pathways of C-14 to human beings in the environment. Intake of C-14 from food source is one of important pathways. In the present study, we examined transfer of C-14 to various parts of rice plant in a paddy soil-to-rice plant system. Rice seedlings in Wagner pots (n=12) were grown for about two months from 7 May 2012 under natural light. The grown plants were moved to a closed chamber on 5 July 2012. The rice plants were grown without water supply from 5 July 2012, and then one liter of C-14 tagged acetate (1.85 MBq) was supplied to the rice plants in the spiked group (n=8) just once on 9 July 2012. For the rice plants in the control group (n=4), uncontaminated water was supplied. These rice plants were air-dried after a harvest on 23 August 2012 and divided into four parts: white rice, bran, rice husk, and the stem and leaf part. The activities of C-14 in the divided parts and air-dried soil samples were determined with a liquid scintillation counting system. Radiocarbon was detected even in the rice plants of the control group. However, the C-14 activity in the soil of the control group was less than the detection limit (1.0 Bq/g). The C-14 activities for the control group decreased in the order of rice husk, bran, white rice, and the stem and leaf part. The detection of C-14 in the control group may be caused by the release of C-14 tagged carbon dioxide from the spiked group. That is, C-14 tagged acetate was converted to carbon dioxide by microbial activity in the spiked group, and then some of the released carbon dioxide was assimilated into

  11. The propagation of a soil H218O labeling through the atmosphere-plant-soil system under drought using H218O and C18OO as two independent proxies

    Science.gov (United States)

    Barthel, Matthias; Sturm, Patrick; Hammerle, Albin; Siegwolf, Rolf; Gentsch, Lydia; Buchmann, Nina; Knohl, Alexander

    2013-04-01

    Above- and belowground processes in plants are tightly coupled via carbon and water flows through the atmosphere-plant-soil system. While recent studies elucidated the influence of drought on the carbon flow through plant and soil using 13C, much less is known about the propagation of 18O. Therefore, this study aimed to examine the timing and intensity of 18O enrichment in soil and shoot CO2 and H2O vapor fluxes of European beech saplings (Fagus sylvatica L.) after applying 18O-labeled water to the soil. A custom-made chamber system, separating shoot from soil compartments, allowed independent measurements of shoot and soil related processes in a controlled climate chamber environment. Gas-exchange of oxygen stable isotopes in CO2 and H2O-vapor served as the main tool for investigation and was monitored in real-time using laser spectroscopy. This is the first study measuring concurrently and continuously the enrichment of 18O in CO2 and H2O in shoot- and soil gas-exchange after applying 18O-labeled water to the soil. Photosynthesis (A) and stomatal conductance (gs) of drought-stressed plants showed an immediate coinciding small increase to the H218O irrigation event after only ~30 min. This rapid information transfer, however, was not accompanied by the arrival of 18O labeled water molecules within the shoot. The actual label induced 18O enrichment in transpired water and CO2 occurred not until ~4h after labeling. Further, the timing of the enrichment of 18O in the transpirational flux was similar in both treatments, thus pointing to similar transport rates. However, drought reduced the 18O exchange rate between H2O and CO2at the shoot level, likely caused by a smaller leaf CO2retroflux. Moreover, 18O exchange between H2O and CO2 occurred also in the soil. However, the there was no difference observed between the treatments.

  12. A sensor array system for monitoring moisture dynamics inunsaturated soil

    Energy Technology Data Exchange (ETDEWEB)

    Salve, R.; Cook, P.J.

    2007-05-15

    To facilitate investigations of moisture dynamics inunsaturated soil, we have developed a technique to qualitatively monitorpatterns of saturation changes. Field results suggest that this device,the sensor array system (SAS), is suitable for determining changes inrelative wetness along vertical soil profiles. The performance of theseprobes was compared with that of the time domain reflectometry (TDR)technique under controlled and field conditions. Measurements from bothtechniques suggest that by obtaining data at high spatial and temporalresolution, the SAS technique was effective in determining patterns ofsaturation changes along a soil profile. In addition, hardware used inthe SAS technique was significantly cheaper than the TDR system, and thesensor arrays were much easier to install along a soilprofile.

  13. Influence of environmental factors on the spatial distribution and diversity of forest soil in Latvia

    Directory of Open Access Journals (Sweden)

    Raimonds Kasparinskis

    2012-02-01

    Full Text Available This study was carried out to determine the spatial relationships between environmental factors (Quaternary deposits, topographical situation, land cover, forest site types, tree species, soil texture and soil groups, and their prefix qualifiers (according to the international Food and Agricultural Organization soil classification system World Reference Base for Soil Resources [FAO WRB]. The results show that it is possible to establish relationships between the distribution of environmental factors and soil groups by applying the generalized linear models in data statistical analysis, using the R 2.11.1 software for processing data from 113 sampling plots throughout the forest territory of Latvia.A very high diversity of soil groups in a relatively similar geological structure was revealed. For various reasons there is not always close relationship between the soil group, their prefix qualifiers and Quaternary deposits, as well as between forest site types, the dominant tree species and specific soil group and its prefix qualifiers. Close correlation was established between Quaternary deposits, forest site types, dominant tree species and soil groups within nutrient-poor sediments and very rich deposits containing free carbonates. No significant relationship was detected between the CORINE Land Cover 2005 classes, topographical situation and soil group.

  14. Exploitation of geographic information system at mapping and modelling of selected soil parameters

    International Nuclear Information System (INIS)

    Palka, B.; Makovnikova, J.; Siran, M.

    2005-01-01

    In this presentation authors describe using of computers and geographic information systems (GIS) at effective use of soil fund, rational exploitation and organization of agricultural soil fund on the territory of the Slovak Republic, its monitoring and modelling. Using and creating of some geographically oriented information systems and databases about soils as well as present trends are discussed

  15. Soil Biochemical Changes Induced by Poultry Litter Application and Conservation Tillage under Cotton Production Systems

    Directory of Open Access Journals (Sweden)

    Seshadri Sajjala

    2012-07-01

    Full Text Available Problems arising from conventional tillage (CT systems (such as soil erosion, decrease of organic matter, environmental damage etc. have led many farmers to the adoption of no-till (NT systems that are more effective in improving soil physical, chemical and microbial properties. Results from this study clearly indicated that NT, mulch tillage (MT, and winter rye cover cropping systems increased the activity of phosphatase, β-glucosidase and arylsulfatase at a 0–10 cm soil depth but decreased the activity of these enzymes at 10–20 cm. The increase in enzyme activity was a good indicator of intensive soil microbial activity in different soil management practices. Poultry litter (PL application under NT, MT, and rye cropping system could be considered as effective management practices due to the improvement in carbon (C content and the biochemical quality at the soil surface. The activities of the studied enzymes were highly correlated with soil total nitrogen (STN soil organic carbon (SOC at the 0–10 cm soil depth, except for acid phosphatase where no correlation was observed. This study revealed that agricultural practices such as tillage, PL, and cover crop cropping system have a noticeable positive effect on soil biochemical activities under cotton production.

  16. Effects of plastic mulches and high tunnel raspberry production systems on soil physicochemical quality indicators

    Science.gov (United States)

    Domagała-Świątkiewicz, Iwona; Siwek, Piotr

    2018-01-01

    In horticulture, degradable materials are desirable alternatives to plastic films. Our aim was to study the impact of soil plastic mulching on the soil properties in the high tunnel and open field production systems of raspberry. The raised beds were mulched with a polypropylene non-woven and two degradable mulches: polypropylene with a photodegradant and non-woven polylactide. The results indicated that the system of raspberry production, as well as the type of mulching had significant impact on soil organic carbon stock, moisture content and water stable aggregate amount. Soils taken from the open field system had a lower bulk density and water stability aggregation index, but higher organic carbon and capillary water content as compared to soils collected from high tunnel conditions. In comparison with the open field system, soil salinity was also found to be higher in high tunnel, as well as with higher P, Mg, Ca, S, Na and B content. Furthermore, mulch covered soils had more organic carbon amount than the bare soils. Soil mulching also enhanced the water capacity expressed as a volume of capillary water content. In addition, mulching improved the soil structure in relation to the bare soil, in particular, in open field conditions. The impact of the compared mulches on soil quality indicators was similar.

  17. Soil remediation process and system

    International Nuclear Information System (INIS)

    Monlux, K.J.

    1992-01-01

    This patent describes a process for remediation of soil containing up to about 30,000 ppm hydrocarbon contaminants. It comprises: providing hydrocarbon-contaminated soil in a divided condition of minus 1 1/2 double-prime to a first confined zone where it is exposed to an open flame; heating while agitating the contaminated soil in an oxidizing atmosphere in the first zone to a temperature below soil ignition within a range of from about 375 degrees F. to about 750 degrees F. for a time sufficient to drive off as vapors a substantial percentage of the hydrocarbon contaminates from the soil; passing hot gases containing the hydrocarbon contaminates from the soil; passing hot gases containing the hydrocarbon vapors from the first zone to a second zone; recovering heat from the hot gases in the second zone to condense a substantial percentage of the hydrocarbon vapors as liquid hydrocarbons; recovering the liquid hydrocarbons; and removing the soil from the first zone as remediated soil having below about 1000 ppm hydrocarbon contaminants

  18. Treatment of septic tank effluents by a full-scale capillary seepage soil biofiltration system.

    Science.gov (United States)

    Fan, Chihhao; Chang, Fang-Chih; Ko, Chun-Han; Teng, Chia-Ji; Chang, Tzi-Chin; Sheu, Yiong-Shing

    2009-03-01

    The purpose of this study is to evaluate the efficiency of septic tank effluent treatment by an underground capillary seepage soil biofiltration system in a suburban area of Taipei, Taiwan. In contrast to traditional subsurface wastewater infiltration systems, capillary seepage soil biofiltration systems initially draw incoming influent upwards from the distribution pipe by capillary and siphonage actions, then spread influent throughout the soil biofiltration bed. The underground capillary seepage soil biofiltration system consists of a train of underground treatment units, including one wastewater distribution tank, two capillary seepage soil biofiltration units in series, and a discharge tank. Each capillary seepage soil biofiltration unit contains one facultative digestion tank and one set of biofiltration beds. At the flow rate of 50 m3/day, average influent concentrations of biochemical oxygen demand (BOD), suspended solid (SS), ammonia nitrogen (NH3-N), and total phosphates (TP), were 36.15 mg/L, 29.14 mg/L, 16.05 mg/L, and 1.75 mg/L, respectively. After 1.5 years of system operation, the measured influent and effluent results show that the treatment efficiencies of the soil biofiltration system for BOD, SS, NH3-N, TP, and total coliforms are 82.96%, 60.95%, 67.17%, 74.86%, and 99.99%, respectively.

  19. A framework of connections between soil and people can help improve sustainability of the food system and soil functions.

    Science.gov (United States)

    Ball, Bruce C; Hargreaves, Paul R; Watson, Christine A

    2018-04-01

    Globally soil quality and food security continue to decrease indicating that agriculture and the food system need to adapt. Improving connection to the soil by knowledge exchange can help achieve this. We propose a framework of three types of connections that allow the targeting of appropriate messages to different groups of people. Direct connection by, for example, handling soil develops soil awareness for management that can be fostered by farmers joining groups on soil-focused farming such as organic farming or no-till. Indirect connections between soil, food and ecosystem services can inform food choices and environmental awareness in the public and can be promoted by, for example, gardening, education and art. Temporal connection revealed from past usage of soil helps to bring awareness to policy workers of the need for the long-term preservation of soil quality for environmental conservation. The understanding of indirect and temporal connections can be helped by comparing them with the operations of the networks of soil organisms and porosity that sustain soil fertility and soil functions.

  20. Phosphorus cycling in natural and low input soil/plant systems: the role of soil microorganisms

    Science.gov (United States)

    Tamburini, F.; Bünemann, E. K.; Oberson, A.; Bernasconi, S. M.; Frossard, E.

    2011-12-01

    Availability of phosphorus (as orthophosphate, Pi) limits biological production in many terrestrial ecosystems. During the first phase of soil development, weathering of minerals and leaching of Pi are the processes controlling Pi concentrations in the soil solution, while in mature soils, Pi is made available by desorption of mineral Pi and mineralization of organic compounds. In agricultural soils additional Pi is supplied by fertilization, either with mineral P and/or organic inputs (animal manure or plant residues). Soil microorganisms (bacteria and fungi) mediate several processes, which are central to the availability of Pi to plants. They play a role in the initial release of Pi from the mineral phase, and through extracellular phosphatase enzymes, they decompose and mineralize organic compounds, releasing Pi. On the other hand, microbial immobilization and internal turnover of Pi can decrease the soil available Pi pool, competing in this way with plants. Using radio- and stable isotopic approaches, we show evidence from different soil/plant systems which points to the central role of the microbial activity. In the presented case studies, P contained in the soil microbial biomass is a larger pool than available Pi. In a soil chronosequence after deglaciation, stable isotopes of oxygen associated to phosphate showed that even in the youngest soils microbial activity highly impacted the isotopic signature of available Pi. These results suggested that microorganisms were rapidly taking up and cycling Pi, using it to sustain their community. Microbial P turnover time was faster in the young (about 20 days) than in older soils (about 120 days), reflecting a different functioning of the microbial community. Microbial community crashes, caused by drying/rewetting and freezing/thawing cycles, were most likely responsible for microbial P release to the available P pool. In grassland fertilization experiments with mineral NK and NPK amendments, microbial P turnover

  1. Inferring Land Surface Model Parameters for the Assimilation of Satellite-Based L-Band Brightness Temperature Observations into a Soil Moisture Analysis System

    Science.gov (United States)

    Reichle, Rolf H.; De Lannoy, Gabrielle J. M.

    2012-01-01

    , and the single scattering albedo. After this climatological calibration, the modeling system can provide L-band brightness temperatures with a global mean absolute bias of less than 10K against SMOS observations, across multiple incidence angles and for horizontal and vertical polarization. Third, seasonal and regional variations in the residual biases are addressed by estimating the vegetation optical depth through state augmentation during the assimilation of the L-band brightness temperatures. This strategy, tested here with SMOS data, is part of the baseline approach for the Level 4 Surface and Root Zone Soil Moisture data product from the planned Soil Moisture Active Passive (SMAP) satellite mission.

  2. Influence of management and environment on Australian wheat: information for sustainable intensification and closing yield gaps

    International Nuclear Information System (INIS)

    Bryan, B A; King, D; Zhao, G

    2014-01-01

    In the future, agriculture will need to produce more, from less land, more sustainably. But currently, in many places, actual crop yields are below those attainable. We quantified the ability for agricultural management to increase wheat yields across 179 Mha of potentially arable land in Australia. Using the Agricultural Production Systems Simulator (APSIM), we simulated the impact on wheat yield of 225 fertilization and residue management scenarios at a high spatial, temporal, and agronomic resolution from 1900 to 2010. The influence of management and environmental variables on wheat yield was then assessed using Spearman’s non-parametric correlation test with bootstrapping. While residue management showed little correlation, fertilization strongly increased wheat yield up to around 100 kg N ha −1  yr −1 . However, this effect was highly dependent on the key environment variables of rainfall, temperature, and soil water holding capacity. The influence of fertilization on yield was stronger in cooler, wetter climates, and in soils with greater water holding capacity. We conclude that the effectiveness of management intensification to increase wheat yield is highly dependent upon local climate and soil conditions. We provide context-specific information on the yield benefits of fertilization to support adaptive agronomic decision-making and contribute to the closure of yield gaps. We also suggest that future assessments consider the economic and environmental sustainability of management intensification for closing yield gaps. (paper)

  3. Mechanical systems with closed orbits on manifolds of revolution

    International Nuclear Information System (INIS)

    Kudryavtseva, E A; Fedoseev, D A

    2015-01-01

    We study natural mechanical systems describing the motion of a particle on a two-dimensional Riemannian manifold of revolution in the field of a central smooth potential. We obtain a classification of Riemannian manifolds of revolution and central potentials on them that have the strong Bertrand property: any nonsingular (that is, not contained in a meridian) orbit is closed. We also obtain a classification of manifolds of revolution and central potentials on them that have the 'stable' Bertrand property: every parallel is an 'almost stable' circular orbit, and any nonsingular bounded orbit is closed. Bibliography: 14 titles

  4. Soil organic carbon assessments in cropping systems using isotopic techniques

    Science.gov (United States)

    Martín De Dios Herrero, Juan; Cruz Colazo, Juan; Guzman, María Laura; Saenz, Claudio; Sager, Ricardo; Sakadevan, Karuppan

    2016-04-01

    Introduction of improved farming practices are important to address the challenges of agricultural production, food security, climate change and resource use efficiency. The integration of livestock with crops provides many benefits including: (1) resource conservation, (2) ecosystem services, (3) soil quality improvements, and (4) risk reduction through diversification of enterprises. Integrated crop livestock systems (ICLS) with the combination of no-tillage and pastures are useful practices to enhance soil organic carbon (SOC) compared with continuous cropping systems (CCS). In this study, the SOC and its fractions in two cropping systems namely (1) ICLS, and (2) CCS were evaluated in Southern Santa Fe Province in Argentina, and the use of delta carbon-13 technique and soil physical fractionation were evaluated to identify sources of SOC in these systems. Two farms inside the same soil cartographic unit and landscape position in the region were compared. The ICLS farm produces lucerne (Medicago sativa Merrill) and oat (Avena sativa L.) grazed by cattle alternatively with grain summer crops sequence of soybean (Glicine max L.) and corn (Zea mays L.), and the farm under continuous cropping system (CCS) produces soybean and corn in a continuous sequence. The soil in the area is predominantly a Typic Hapludoll. Soil samples from 0-5 and 0-20 cm depths (n=4) after the harvest of grain crops were collected in each system and analyzed for total organic carbon (SOC, 0-2000 μm), particulate organic carbon (POC, 50-100 μm) and mineral organic carbon (MOC, is probably due to the presence of deep roots under pastures in ICLS. Delta carbon-13 values for 0-5 cm were -22.9, -21.2 and -19.9 per mil for REF, ICLS and CCS, respectively (Pis explained by the presence of tree species with high lignin content in natural vegetation. Lignin has lower delta carbon-13 compared to cellulose (dominating in crops and pastures), which is present in greater proportion in plant residues of

  5. The effect of intrinsic soil properties on soil quality assessments

    Directory of Open Access Journals (Sweden)

    Alessandro Samuel-Rosa

    2013-10-01

    Full Text Available The assessment of soil quality is based on indicators and indices derived from soil properties. However, intrinsic soil properties may interfere with other soil properties that vary under different land uses and are used to calculate the indices. The aim of this study was to assess the extent to which intrinsic soil properties (clay and iron oxide contents explain variable soil properties (sum of bases, potential acidity, organic carbon, total porosity, and bulk density under different land uses (native forest, no-tillage and conventional agriculture on small family farms in Southern Brazil. The results showed that the five properties evaluated can be included in soil quality assessments and are not influenced by the clay and iron oxide contents. It was concluded that for little weathered 1:1 and 2:1 phyllosilicate rich-soils, if the difference between the maximum and the minimum clay content under the different land uses is less than about 200 g kg-1 and the iron oxide content less than about 15 g kg-1, the physico-chemical soil properties in the surface layer are determined mostly by the land use.

  6. Cultural Patterns of Soil Understanding

    Science.gov (United States)

    Patzel, Nikola; Feller, Christian

    2017-04-01

    Living soil supports all terrestrial ecosystems. The only global threat to earth's soils comes from human societies' land use and resource consuming activities. Soil perception and understanding by soil scientists are mainly drawn from biophysical parameters and found within Cartesian rationality, and not, or much less consciously from its rather intangible cultural dimension. But nevertheless, human soil perception, soil awareness, and soil relation are a cultural phenomenon, too. Aiming at soil awareness and education, it is of first order importance for the soil science community and the IUSS to study, discuss and communicate also about the cultural perceptions and representations of soil. For any society, cultural patterns in their relation to soil encompass: (i) General culturally underlying structures like (religious or 'secular') myths and belief systems. (ii) The personal, individual relation to/with and behaviour towards soil. This includes implicit concepts of soil being part integral concepts of landscape because the large majority of humans don't see soil as a distinct object. This communication would be to make evident: (i) the importance of cultural patterns and psychic/psychological background concerning soil, by case studies and overviews on different cultural areas, (ii) the necessity to develop reflections on this topic as well to communicate about soil with large public, as to raise awareness soil scientists to the cultural dimension of soils. A working group was recently founded at IUSS (Division 4) on this topic.

  7. Contributions of Precipitation and Soil Moisture Observations to the Skill of Soil Moisture Estimates in a Land Data Assimilation System

    Science.gov (United States)

    Reichle, Rolf H.; Liu, Qing; Bindlish, Rajat; Cosh, Michael H.; Crow, Wade T.; deJeu, Richard; DeLannoy, Gabrielle J. M.; Huffman, George J.; Jackson, Thomas J.

    2011-01-01

    The contributions of precipitation and soil moisture observations to the skill of soil moisture estimates from a land data assimilation system are assessed. Relative to baseline estimates from the Modern Era Retrospective-analysis for Research and Applications (MERRA), the study investigates soil moisture skill derived from (i) model forcing corrections based on large-scale, gauge- and satellite-based precipitation observations and (ii) assimilation of surface soil moisture retrievals from the Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR-E). Soil moisture skill is measured against in situ observations in the continental United States at 44 single-profile sites within the Soil Climate Analysis Network (SCAN) for which skillful AMSR-E retrievals are available and at four CalVal watersheds with high-quality distributed sensor networks that measure soil moisture at the scale of land model and satellite estimates. The average skill (in terms of the anomaly time series correlation coefficient R) of AMSR-E retrievals is R=0.39 versus SCAN and R=0.53 versus CalVal measurements. The skill of MERRA surface and root-zone soil moisture is R=0.42 and R=0.46, respectively, versus SCAN measurements, and MERRA surface moisture skill is R=0.56 versus CalVal measurements. Adding information from either precipitation observations or soil moisture retrievals increases surface soil moisture skill levels by IDDeltaR=0.06-0.08, and root zone soil moisture skill levels by DeltaR=0.05-0.07. Adding information from both sources increases surface soil moisture skill levels by DeltaR=0.13, and root zone soil moisture skill by DeltaR=0.11, demonstrating that precipitation corrections and assimilation of satellite soil moisture retrievals contribute similar and largely independent amounts of information.

  8. Smart system for safe and optimal soil investigation in urban areas

    Directory of Open Access Journals (Sweden)

    Ahmad Alqadad

    2017-12-01

    Full Text Available This paper discusses the challenges and difficulties experienced during soil investigation in urban areas using drilling machines and soil sampling. The focus is on the consequences of a lack of data on the subsoil profile and presence of utilities, which could cause major accidents with severe economic and social losses, resulting in constriction activities being delayed and urban services being disrupted. This paper describes certain accidents related to soil investigation in Qatar and their consequences, as well as the lessons learned from these accidents. In order to meet the challenges of soil investigation in urban areas, this paper presents a solution based on smart technology, which includes: (i a geotechnical information system with update data concerning the soil profile, soil surface, utilities locations, and water table level; (ii tools for data management, analysis, and visualization; and (iii a user interface that allows authorities, companies, and citizens to access authorized data via a graphic interface, update data, and send messages and alerts in the case of any incident occurring. Finally, the paper presents a promising perspective for the development of smart drilling devices, which record data related to the functioning of a drilling machine and transmit data to the smart soil investigation system. Keywords: Soil investigation, Smart, Urban area, Drill borehole, GIS, Underground utility

  9. Implications of soil mixing for NAPL source zone remediation: Column studies and modeling of field-scale systems.

    Science.gov (United States)

    Olson, Mitchell R; Sale, Tom C

    2015-01-01

    Soil remediation is often inhibited by subsurface heterogeneity, which constrains contaminant/reagent contact. Use of soil mixing techniques for reagent delivery provides a means to overcome contaminant/reagent contact limitations. Furthermore, soil mixing reduces the permeability of treated soils, thus extending the time for reactions to proceed. This paper describes research conducted to evaluate implications of soil mixing on remediation of non-aqueous phase liquid (NAPL) source zones. The research consisted of column studies and subsequent modeling of field-scale systems. For column studies, clean influent water was flushed through columns containing homogenized soils, granular zero valent iron (ZVI), and trichloroethene (TCE) NAPL. Within the columns, NAPL depletion occurred due to dissolution, followed by either column-effluent discharge or ZVI-mediated degradation. Complete removal of TCE NAPL from the columns occurred in 6-8 pore volumes of flow. However, most of the TCE (>96%) was discharged in the column effluent; less than 4% of TCE was degraded. The low fraction of TCE degraded is attributed to the short hydraulic residence time (10 m) and reducing permeability by one-or-more orders of magnitude, the residence time could be greatly extended, potentially for periods of years to decades. Model output indicates that the fraction of TCE degraded can be increased to >99.9%, given typical post-mixing soil permeability values. These results suggest that remediation performance can be greatly enhanced by combining contaminant degradation with an extended residence time. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Variable flow controls of closed system pumps for energy savings in maritime power systems

    DEFF Research Database (Denmark)

    Su, Chun-Lien; Liao, Chi-Hsiang; Chou, Tso-Chu

    2016-01-01

    and field tests of a practical auxiliary boiler feed water management system on a commercial vessel. It is proved that the proposed method can maintain constant water pressure for closed system pumps and provide an efficient way to measure energy savings and maintenance benefits. The results serve......Pumps are extensively used in maritime industries as marine vessels utilize a wide range of pumps and pumping techniques to transfer and distribute all types of air and fluids. The electrical energy consumed by the various motors accounts for about 70% of a vessel’s total power consumption......, and this presents a problem in unique marine environments. Such situations are especially conducive to energy-saving strategies using variable frequency drives (VFDs) in centrifugal load service. This paper presents the design and results of applying variable frequency constant pressure technology in closed system...

  11. Influence of ground water on soil-structure interaction

    International Nuclear Information System (INIS)

    Costantino, C.J.; Graves, H.L.

    1987-01-01

    The basic problem consists of a liner flexible structure situated at or near the surface of a soil half-space. In keeping with typical small strain seismic analyses, the soil skeleton is represented as a linear medium in which all potential nonlinearities are at most lumped together into an equivalent hysteretic damping modulus. In addition, the ground water level is located at some depth relatively close to the structure, and in a position to impact on the seismic response of the facility. In order to estimate the response of this oil-water system, the two-phased medium formulation of Biot was used to treat the response of the solids and water as two separate linear media, coupled together through soil permeability and volume effects. (orig./HP)

  12. Soil phosphatase and urease activities impacted by cropping systems and water management

    Science.gov (United States)

    Soil enzymes can play an important role in nutrient availability to plants. Consequently, soil enzyme measurements can provide useful information on soil fertility for crop production. We examined the impact of cropping system and water management on phosphatase, urease, and microbial biomass C in s...

  13. Water erosion and soil water infiltration in different stages of corn development and tillage systems

    Directory of Open Access Journals (Sweden)

    Daniel F. de Carvalho

    2015-11-01

    Full Text Available ABSTRACTThis study evaluated soil and water losses, soil water infiltration and infiltration rate models in soil tillage systems and corn (Zea mays, L. development stages under simulated rainfall. The treatments were: cultivation along contour lines, cultivation down the slope and exposed soil. Soil losses and infiltration in each treatment were quantified for rains applied using a portable simulator, at 0, 30, 60 and 75 days after planting. Infiltration rates were estimated using the models of Kostiakov-Lewis, Horton and Philip. Based on the obtained results, the combination of effects between soil tillage system and corn development stages reduces soil and water losses. The contour tillage system promoted improvements in soil physical properties, favoring the reduction of erosion in 59.7% (water loss and 86.6% (soil loss at 75 days after planting, and the increase in the stable infiltration rate in 223.3%, compared with the exposed soil. Associated to soil cover, contour cultivation reduces soil and water losses, and the former is more influenced by management. Horton model is the most adequate to represent soil water infiltration rate under the evaluated conditions.

  14. A drill-soil system modelization for future Mars exploration

    Science.gov (United States)

    Finzi, A. E.; Lavagna, M.; Rocchitelli, G.

    2004-01-01

    This paper presents a first approach to the problem of modeling a drilling process to be carried on in the space environment by a dedicated payload. Systems devoted to work in space present very strict requirements in many different fields such as thermal response, electric power demand, reliability and so on. Thus, models devoted to the operational behaviour simulation represent a fundamental help in the design phase and give a great improvement in the final product quality. As the required power is the crucial constraint within drilling devices, the tool-soil interaction modelization and simulation are finalized to the computation of the power demand as a function of both the drill and the soil parameters. An accurate study of the tool and the soil separately has been firstly carried on and, secondly their interaction has been analyzed. The Dee-Dri system, designed by Tecnospazio and to be part of the lander components in the NASA's Mars Sample Return Mission, has been taken as the tool reference. The Deep-Drill system is a complex rotary tool devoted to the soil perforation and sample collection; it has to operate in a Martian zone made of rocks similar to the terrestrial basalt, then the modelization is restricted to the interaction analysis between the tool and materials belonging to the rock set. The tool geometric modelization has been faced by a finite element approach with a Langrangian formulation: for the static analysis a refined model is assumed considering both the actual geometry of the head and the rod screws; a simplified model has been used to deal with the dynamic analysis. The soil representation is based on the Mohr-Coulomb crack criterion and an Eulerian approach has been selected to model it. However, software limitations in dealing with the tool-soil interface definition required assuming a Langrangian formulation for the soil too. The interaction between the soil and the tool has been modeled by extending the two-dimensional Nishimatsu

  15. Evaluation of a Soil Moisture Data Assimilation System Over West Africa

    Science.gov (United States)

    Bolten, J. D.; Crow, W.; Zhan, X.; Jackson, T.; Reynolds, C.

    2009-05-01

    A crucial requirement of global crop yield forecasts by the U.S. Department of Agriculture (USDA) International Production Assessment Division (IPAD) is the regional characterization of surface and sub-surface soil moisture. However, due to the spatial heterogeneity and dynamic nature of precipitation events and resulting soil moisture, accurate estimation of regional land surface-atmosphere interactions based sparse ground measurements is difficult. IPAD estimates global soil moisture using daily estimates of minimum and maximum temperature and precipitation applied to a modified Palmer two-layer soil moisture model which calculates the daily amount of soil moisture withdrawn by evapotranspiration and replenished by precipitation. We attempt to improve upon the existing system by applying an Ensemble Kalman filter (EnKF) data assimilation system to integrate surface soil moisture retrievals from the NASA Advanced Microwave Scanning Radiometer (AMSR-E) into the USDA soil moisture model. This work aims at evaluating the utility of merging satellite-retrieved soil moisture estimates with the IPAD two-layer soil moisture model used within the DBMS. We present a quantitative analysis of the assimilated soil moisture product over West Africa (9°N- 20°N; 20°W-20°E). This region contains many key agricultural areas and has a high agro- meteorological gradient from desert and semi-arid vegetation in the North, to grassland, trees and crops in the South, thus providing an ideal location for evaluating the assimilated soil moisture product over multiple land cover types and conditions. A data denial experimental approach is utilized to isolate the added utility of integrating remotely-sensed soil moisture by comparing assimilated soil moisture results obtained using (relatively) low-quality precipitation products obtained from real-time satellite imagery to baseline model runs forced with higher quality rainfall. An analysis of root-zone anomalies for each model

  16. Greenhouse gas fluxes from agricultural soils under organic and non-organic management — A global meta-analysis

    Energy Technology Data Exchange (ETDEWEB)

    Skinner, Colin, E-mail: colin.skinner@fibl.org [Research Institute of Organic Agriculture (FiBL), Ackerstrasse 21, 5070 Frick (Switzerland); Gattinger, Andreas, E-mail: andreas.gattinger@fibl.org [Research Institute of Organic Agriculture (FiBL), Ackerstrasse 21, 5070 Frick (Switzerland); Muller, Adrian, E-mail: adrian.mueller@fibl.org [Research Institute of Organic Agriculture (FiBL), Ackerstrasse 21, 5070 Frick (Switzerland); Mäder, Paul, E-mail: paul.maeder@fibl.org [Research Institute of Organic Agriculture (FiBL), Ackerstrasse 21, 5070 Frick (Switzerland); Fließbach, Andreas, E-mail: andreas.fliessbach@fibl.org [Research Institute of Organic Agriculture (FiBL), Ackerstrasse 21, 5070 Frick (Switzerland); Stolze, Matthias, E-mail: matthias.stolze@fibl.org [Research Institute of Organic Agriculture (FiBL), Ackerstrasse 21, 5070 Frick (Switzerland); Ruser, Reiner, E-mail: reiner.ruser@uni-hohenheim.de [Fertilisation and Soil Matter Dynamics (340i), Institute of Crop Science, University of Hohenheim, Fruwirthstraße 20, 70599 Stuttgart (Germany); Niggli, Urs, E-mail: urs.niggli@fibl.org [Research Institute of Organic Agriculture (FiBL), Ackerstrasse 21, 5070 Frick (Switzerland)

    2014-01-01

    It is anticipated that organic farming systems provide benefits concerning soil conservation and climate protection. A literature search on measured soil-derived greenhouse gas (GHG) (nitrous oxide and methane) fluxes under organic and non-organic management from farming system comparisons was conducted and followed by a meta-analysis. Up to date only 19 studies based on field measurements could be retrieved. Based on 12 studies that cover annual measurements, it appeared with a high significance that area-scaled nitrous oxide emissions from organically managed soils are 492 ± 160 kg CO{sub 2} eq. ha{sup −1} a{sup −1} lower than from non-organically managed soils. For arable soils the difference amounts to 497 ± 162 kg CO{sub 2} eq. ha{sup −1} a{sup −1}. However, yield-scaled nitrous oxide emissions are higher by 41 ± 34 kg CO{sub 2} eq. t{sup −1} DM under organic management (arable and use). To equalize this mean difference in yield-scaled nitrous oxide emissions between both farming systems, the yield gap has to be less than 17%. Emissions from conventionally managed soils seemed to be influenced mainly by total N inputs, whereas for organically managed soils other variables such as soil characteristics seemed to be more important. This can be explained by the higher bioavailability of the synthetic N fertilisers in non-organic farming systems while the necessary mineralisation of the N sources under organic management leads to lower and retarded availability. Furthermore, a higher methane uptake of 3.2 ± 2.5 kg CO{sub 2} eq. ha{sup −1} a{sup −1} for arable soils under organic management can be observed. Only one comparative study on rice paddies has been published up to date. All 19 retrieved studies were conducted in the Northern hemisphere under temperate climate. Further GHG flux measurements in farming system comparisons are required to confirm the results and close the existing knowledge gaps. - Highlights: • Lower area-scaled nitrous

  17. Gain Scheduling Control based on Closed-Loop System Identification

    DEFF Research Database (Denmark)

    Bendtsen, Jan Dimon; Trangbæk, Klaus

    the first and a second operating point is identified in closed-loop using system identification methods with open-loop properties. Next, a linear controller is designed for this linearised model, and gain scheduling control can subsequently be achieved by interpolating between each controller...

  18. Nuclear equipment to determine soil and water mass attenuation coefficients

    International Nuclear Information System (INIS)

    Zucchi, O.L.A.D.; Nascimento Filho, V.F. do

    1984-01-01

    The feasibility of substituting the monochannel gamma spectrometer, traditionally used in the gamma ray attenuation technique, for a less sophisticated and less expensive system of integral counting is studied. The proposed system can be operated by a non-specialized person. Three detection systems were used in the determination of the mass attenuation coefficients for different types of soil and for water. (M.A.C.) [pt

  19. Root systems and soil microbial biomass under no-tillage system

    Directory of Open Access Journals (Sweden)

    Venzke Filho Solismar de Paiva

    2004-01-01

    Full Text Available Some root parameters such as distribution, length, diameter and dry matter are inherent to plant species. Roots can influence microbial population during vegetative cycle through the rhizodeposits and, after senescence, integrating the soil organic matter pool. Since they represent labile substrates, especially regarding nitrogen, they can determine the rate of nutrient availability to the next crop cultivated under no-tillage (NT. The root systems of two crop species: maize (Zea mays L. cultivar Cargill 909 and soybean [Glycine max (L. Merr.] cultivar Embrapa 59, were compared in the field, and their influence on spatial distribution of the microbial C and N in a clayey-textured Typic Hapludox cultivated for 22 years under NT, at Tibagi, State of Paraná (PR, Brazil, was determined. Digital image processing and nail-plate techniques were used to evaluate 40 plots of a 80 ´ 50 ´ 3 cm soil profile. It was observed that 36% and 30% of the maize and soybeans roots, respectively, are concentrated in the 0 to 10 cm soil layer. The percent distribution of root dry matter was similar for both crops. The maize roots presented a total of 1,324 kg C ha-1 and 58 kg N ha-1, with higher root dry matter density and more roots in decomposition in the upper soil layer, decreasing with depth. The soybean roots (392 kg C ha-1 and 21 kg N ha-1 showed higher number of thinner roots and higher density per length unity compared to the maize. The maize roots enhanced microbial-C down to deeper soil layers than did the soybean roots. The microbial N presented a better correlation with the concentration of thin active roots and with roots in decomposition or in indefinite shape, possibly because of higher concentration of C and N easily assimilated by soil microorganisms.

  20. Degree of saturation effect on the grout-soil interface shear strength of soil nailing

    Directory of Open Access Journals (Sweden)

    Wang Qiong

    2016-01-01

    Full Text Available In the grouted soil nailing system, the bonding strength of cement grout-soil interface offers the required resistance to maintain the stability of whole structure. In practice, soil nailing applications are often placed at unsaturated conditions, such as soil slopes, shallow foundations, retaining walls and pavement structures. In these cases, the water content in the soil nail zone may increase or decrease due to rain water or dry weather, and even cannot become saturated during their design service life. In this study, the effect of water content (degree of saturation on the shear strength of interface between cement grout and sand are experimentally investigated by means of direct shear test. Meanwhile the water retention curve was determined and interface microstructure was observed. Experimental results show that the shear strength of interface changes non-monotonously with degree of saturation when the interface was prepared, due to the non-monotonousness of the cohesiveness between soil particles. The less the cohesiveness between sand particles, the more grout was observed been penetrated into the voids, and thus the larger the interface shear stress.

  1. Soil Fertility and Radicular System Depth of Sand Coastal Plain Forest

    Science.gov (United States)

    Casagrande, José Carlos; Akemi Sato, Claudia; Reis-Duarte, Rose Mary; Soares, Marcio Roberto; Sérgio Galvão Bueno, Mário

    2010-05-01

    The sand coastal plain vegetation (Restinga Forest) is a type of ecosystem associated with the Atlantic Forest constituted of mosaics, which occur in areas of great ecological diversity. This vegetation is currently assigned as edaphic communities. In this study we present data on soil fertility in different vegetation physiognomies to discuss on abiotic factors related to Restinga Forest stability and recovery potential. This work was carried out in several points of Restinga Forest in the litoral coast of the state of São Paulo, namely: State Park of the Serra do Mar, Picinguaba, in the city of Ubatuba (23°20' e 23°22' S / 44°48' e 44°52' W); State Park of Anchieta Island, in the city of Ubatuba (45°02' e 45°05' W / 23°31' e 23° 45' S); Restinga Forest in the residential joint ownership Riviera of São Lourenço, in the city of Bertioga (46°08' W e 23°51' S); Ecological Station Juréia-Itatins, Ecological Station of Chauas , in the city of Iguape (24°45' S e 47°33' W) and State Park of Cardoso Island, Pereirinha Restinga Forest, in the city of Cananéia (25°03'05" e 25°18'18" S / 47°53'48" e 48° 05'42" W), Brazil. Sampling was carried out as follows in every area above mentioned. One sample was made of 15 subsamples of each area collected in each depth (one in 0 - 5, 5 - 10, 10 - 15, 15 - 20, and another in 0 - 20, 20 - 40, 40 and 60 cm). Soil characteristics analyzed were pH, P, Na, K, Ca, Mg, S, H + Al, Al, B, Cu, Fe, Mn, Zn contents and base saturation, cation exchange capacity and aluminum saturation. All areas investigated showed very low contents of phosphorous, calcium and magnesium. The base saturation, less than 10, was low due to low amounts of Na, K, Ca and Mg, indicating low nutritional reserve into the soil. The nutritional reserve is present primarily in a depth of 15 cm, although mainly in the vegetable biomass. The level of calcium and magnesium were mainly low in the subsurface soil layer, associate with high concentration of

  2. Evaluating the Performance of a Novel Embedded Closed-loop System.

    Science.gov (United States)

    Leelarathna, Lalantha; Thabit, Hood; Allen, Janet M; Nodale, Marianna; Wilinska, Malgorzata E; Powell, Kevin; Lane, Stephen; Evans, Mark L; Hovorka, Roman

    2014-03-01

    The objective was to assess the reliability of a novel automated closed-loop glucose control system developed within the AP@home consortium in adults with type 1 diabetes. Eight adults with type 1 diabetes on insulin pump therapy (3 men; ages 40.5 ± 14.3 years; HbA1c 8.2 ± 0.8%) participated in an open-label, single-center, single-arm, 12-hour overnight study performed at the clinical research facility. A standardized evening meal (80 g CHO) accompanied by prandial insulin boluses were given at 19:00 followed by an optional snack of 15 g at 22:00 without insulin bolus. Automated closed-loop glucose control was started at 19:00 and continued until 07:00 the next day. Basal insulin delivery (Accu-Chek Spirit, Roche) was automatically adjusted by Cambridge model predictive control algorithm, running on a purpose-built embedded device, based on real-time continuous glucose monitor readings (Dexcom G4 Platinum). Closed-loop system was operational as intended over 99% of the time. Overnight plasma glucose levels (22:00 to 07:00) were within the target range (3.9 to 8.0 mmol/l) for 75.4% (37.5, 92.9) of the time without any time spent in hypoglycemia (system. The time spent in target glucose level overnight was comparable to results of previously published studies. Further developments to miniaturize the system for home studies are warranted. © 2014 Diabetes Technology Society.

  3. Design validation and performance of closed loop gas recirculation system

    International Nuclear Information System (INIS)

    Kalmani, S.D.; Majumder, G.; Mondal, N.K.; Shinde, R.R.; Joshi, A.V.

    2016-01-01

    A pilot experimental set up of the India Based Neutrino Observatory's ICAL detector has been operational for the last 4 years at TIFR, Mumbai. Twelve glass RPC detectors of size 2 × 2 m 2 , with a gas gap of 2 mm are under test in a closed loop gas recirculation system. These RPCs are continuously purged individually, with a gas mixture of R134a (C 2 H 2 F 4 ), isobutane (iC 4 H 10 ) and sulphur hexafluoride (SF 6 ) at a steady rate of 360 ml/h to maintain about one volume change a day. To economize gas mixture consumption and to reduce the effluents from being released into the atmosphere, a closed loop system has been designed, fabricated and installed at TIFR. The pressure and flow rate in the loop is controlled by mass flow controllers and pressure transmitters. The performance and integrity of RPCs in the pilot experimental set up is being monitored to assess the effect of periodic fluctuation and transients in atmospheric pressure and temperature, room pressure variation, flow pulsations, uniformity of gas distribution and power failures. The capability of closed loop gas recirculation system to respond to these changes is also studied. The conclusions from the above experiment are presented. The validations of the first design considerations and subsequent modifications have provided improved guidelines for the future design of the engineering module gas system.

  4. Stoked nondynamos: sustaining field in magnetically non-closed systems

    International Nuclear Information System (INIS)

    Byington, B M; Brummell, N H; Stone, J M; Gough, D O

    2014-01-01

    Much effort has gone into identifying and classifying systems that might be capable of dynamo action, i.e. capable of generating and sustaining magnetic field indefinitely against dissipative effects in a conducting fluid. However, it is difficult, if not almost technically impossible, to derive a method of determining in both an absolutely conclusive and a pragmatic manner whether a system is a dynamo or not in the nonlinear regime. This problem has generally been examined only for closed systems, despite the fact that most realistic situations of interest are not strictly closed. Here we examine the even more complex problem of whether a known nondynamo closed system can be distinguished pragmatically from a true dynamo when a small input of magnetic field to the system is allowed. We call such systems ‘stoked nondynamos’ owing to the ‘stoking’ or augmentation of the magnetic field in the system. It may seem obvious that magnetic energy can be sustained in such systems since there is an external source, but crucial questions remain regarding what level is maintained and whether such nondynamo systems can be distinguished from a true dynamo. In this paper, we perform 3D nonlinear numerical simulations with time-dependent ABC forcing possessing known dynamo properties. We find that magnetic field can indeed be maintained at a significant stationary level when stoking a system that is a nondynamo when not stoked. The maintained state results generally from an eventual rough balance of the rates of input and decay of magnetic field. We find that the relevance of this state is dictated by a parameter κ representing the correlation of the resultant field with the stoking forcing function. The interesting regime is where κ is small but non-zero, as this represents a middle ground between a state where the stoking has no effect on the pre-existing nondynamo properties and a state where the effect of stoking is easily detectable. We find that in this regime, (a

  5. Toward Soil Spatial Information Systems (SSIS) for global modeling and ecosystem management

    Science.gov (United States)

    Baumgardner, Marion F.

    1995-01-01

    The general objective is to conduct research to contribute toward the realization of a world soils and terrain (SOTER) database, which can stand alone or be incorporated into a more complete and comprehensive natural resources digital information system. The following specific objectives are focussed on: (1) to conduct research related to (a) translation and correlation of different soil classification systems to the SOTER database legend and (b) the inferfacing of disparate data sets in support of the SOTER Project; (2) to examine the potential use of AVHRR (Advanced Very High Resolution Radiometer) data for delineating meaningful soils and terrain boundaries for small scale soil survey (range of scale: 1:250,000 to 1:1,000,000) and terrestrial ecosystem assessment and monitoring; and (3) to determine the potential use of high dimensional spectral data (220 reflectance bands with 10 m spatial resolution) for delineating meaningful soils boundaries and conditions for the purpose of detailed soil survey and land management.

  6. Carbon storage in soil size fractions under two cacao agroforestry systems in Bahia, Brazil.

    Science.gov (United States)

    Gama-Rodrigues, Emanuela F; Ramachandran Nair, P K; Nair, Vimala D; Gama-Rodrigues, Antonio C; Baligar, Virupax C; Machado, Regina C R

    2010-02-01

    Shaded perennial agroforestry systems contain relatively high quantities of soil carbon (C) resulting from continuous deposition of plant residues; however, the extent to which the C is sequestered in soil will depend on the extent of physical protection of soil organic C (SOC). The main objective of this study was to characterize SOC storage in relation to soil fraction-size classes in cacao (Theobroma cacao L.) agroforestry systems (AFSs). Two shaded cacao systems and an adjacent natural forest in reddish-yellow Oxisols in Bahia, Brazil were selected. Soil samples were collected from four depth classes to 1 m depth and separated by wet-sieving into three fraction-size classes (>250 microm, 250-53 microm, and <53 microm)-corresponding to macroaggregate, microaggregate, and silt-and-clay size fractions-and analyzed for C content. The total SOC stock did not vary among systems (mean: 302 Mg/ha). On average, 72% of SOC was in macroaggregate-size, 20% in microaggregate-size, and 8% in silt-and-clay size fractions in soil. Sonication of aggregates showed that occlusion of C in soil aggregates could be a major mechanism of C protection in these soils. Considering the low level of soil disturbances in cacao AFSs, the C contained in the macroaggregate fraction might become stabilized in the soil. The study shows the role of cacao AFSs in mitigating greenhouse gas (GHG) emission through accumulation and retention of high amounts of organic C in the soils and suggests the potential benefit of this environmental service to the nearly 6 million cacao farmers worldwide.

  7. Approximate Models for Closed-Loop Trajectory Tracking in Underactuated Systems

    Data.gov (United States)

    National Aeronautics and Space Administration — Control of robotic systems, as a field, spans both traditional closed-loop feedback techniques and modern machine learning strategies, which are primarily open-loop....

  8. Sand amendment enhances bioelectrochemical remediation of petroleum hydrocarbon contaminated soil.

    Science.gov (United States)

    Li, Xiaojing; Wang, Xin; Ren, Zhiyong Jason; Zhang, Yueyong; Li, Nan; Zhou, Qixing

    2015-12-01

    Bioelectrochemical system is an emerging technology for the remediation of soils contaminated by petroleum hydrocarbons. However, performance of such systems can be limited by the inefficient mass transport in soil. Here we report a new method of sand amendment, which significantly increases both oxygen and proton transports, resulting to increased soil porosity (from 44.5% to 51.3%), decreased Ohmic resistance (by 46%), and increased charge output (from 2.5 to 3.5Cg(-1)soil). The degradation rates of petroleum hydrocarbons increased by up to 268% in 135d. The degradation of n-alkanes and polycyclic aromatic hydrocarbons with high molecular weight was accelerated, and denaturing gradient gel electrophoresis showed that the microbial community close to the air-cathode was substantially stimulated by the induced current, especially the hydrocarbon degrading bacteria Alcanivorax. The bioelectrochemical stimulation imposed a selective pressure on the microbial community of anodes, including that far from the cathode. These results suggested that sand amendment can be an effective approach for soil conditioning that will enhances the bioelectrochemical removal of hydrocarbons in contaminated soils. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Analytical and experimental investigation of closed-cycle sorption cooling systems

    Science.gov (United States)

    Liu, Lianquan

    1992-01-01

    The first part of the present thesis concerns the Coefficient of Performance (COP) of two types of closed-cycle sorption cooling systems: the Single Effect Liquid (SEL) absorption system and the Regenerative Solid (RS) adsorption system. When specific cycle configurations are considered, the COP is always less than that allowed by the second law. The potential of the two systems to approach the second law limit is considered in this work. The analysis shows that COP of a SEL system using LiBr-H2O is not limited by one, as believed before, and that the COP of a RS cooling system using zeolite-water is considerably larger than that of the SEL system. This is due to recovery of the heat of adsorption which is made possible by capturing the thermal wave in the solid adsorbent. In the second part, a one dimensional model has been developed for a real RS cooling system featured by finite heat transfer coefficients. The problem is solved numerically to yield the temperature and uptake profiles, COP, and cooling capacity and cooling rates. The effects of various design and operating parameters on system performance have been investigated by using the model. The convective heat transfer coefficient at the inner wall of the fluid channel passing through the zeolite columns, the flow rate of the heat transfer fluid, the condenser and evaporator temperature are identified as the most significant factors. A new correlation of adsorption equilibrium has been derived in this thesis. The derivation is based on established thermodynamic relationships and is shown to be able to well represent the data of three adsorption pairs widely used in sorption cooling applications: zeolite-water, silica gel-water and activated carbon-methanol. Finally, in the experimental part of the present work a test set-up of a zeolite-water heat and mass regenerator was designed, instrumented and built. Temperature profiles at various operating conditions were measured. The data of a 'single blow' mode

  10. Modeling soil organic carbon stocks and changes in Spain using the GEFSOC system

    Science.gov (United States)

    Álvaro-Fuentes, Jorge; Easter, Mark; Cantero-Martínez, Carlos; Paustian, Keith

    2010-05-01

    Currently, there is little information about soil organic carbon (SOC) stocks in Spain. To date the effects of land-use and soil management on SOC stocks in Spain have been evaluated in experimental fields under certain soil and climate conditions. However, these field experiments do not account for the spatial variability in management, cropping systems and soil and climate characteristics that exist in the whole territory. More realistic approaches like ecosystem-level dynamic simulation systems linked to geographic information systems (GIS) allow better assessments of SOC stocks at a regional or national level. The Global Environmental Facility Soil Organic Carbon (GEFSOC) system was recently built for this purpose (Milne et al., 2007) and it incorporates three widely used models for estimating SOC dynamics: (a) the Century ecosystem model; (b) the RothC soil C decomposition model; and (c) the Intergovernmental Panel on Climate Change (IPCC) method for assessing soil C at regional scales. We modeled 9.5 Mha in northeast Spain using the GEFSOC system to predict SOC stocks and changes comprising: pasture, forest, cereal-fallow, cereal monoculture, orchards, rice, irrigated land and grapes and olives. The spatial distribution of the different land use categories and their change over time was obtained from the European Corine database and from Spanish census data on land use from 1926 to 2007. At the same time, current and historical management information was collected from different sources in order to have a fairly well picture of changes in land use and management for this area. Soil parameters needed by the system were obtained from the European soil map (1 km x 1 km) and climate data was produced by the Meteorology State Agency (Ministry of the Environment and Rural and Marine Environs of Spain). The SOC stocks simulated were validated with SOC values from the European SOC map and from other national studies. Modeled SOC results suggested that spatial

  11. Uranium-contaminated soil pilot treatment study

    International Nuclear Information System (INIS)

    Turney, W.R.J.R.; Mason, C.F.V.; Michelotti, R.A.

    1996-01-01

    A pilot treatment study is proving to be effective for the remediation of uranium-contaminated soil from a site at the Los Alamos National Laboratory by use of a two-step, zero-discharge, 100% recycle system. Candidate uranium-contaminated soils were characterized for uranium content, uranium speciation, organic content, size fractionization, and pH. Geochemical computer codes were used to forecast possible uranium leach scenarios. Uranium contamination was not homogenous throughout the soil. In the first step, following excavation, the soil was sorted by use of the ThemoNuclean Services segmented gate system. Following the sorting, uranium-contaminated soil was remediated in a containerized vat leach process by use of sodium-bicarbonate leach solution. Leach solution containing uranium-carbonate complexes is to be treated by use of ion-exchange media and then recycled. Following the treatment process the ion exchange media will be disposed of in an approved low-level radioactive landfill. It is anticipated that treated soils will meet Department of Energy site closure guidelines, and will be given open-quotes no further actionclose quotes status. Treated soils are to be returned to the excavation site. A volume reduction of contaminated soils will successfully be achieved by the treatment process. Cost of the treatment (per cubic meter) is comparable or less than other current popular methods of uranium-contamination remediation

  12. Soil surface roughness decay in contrasting climates, tillage types and management systems

    Science.gov (United States)

    Vidal Vázquez, Eva; Bertol, Ildegardis; Tondello Barbosa, Fabricio; Paz-Ferreiro, Jorge

    2014-05-01

    Soil surface roughness describes the variations in the elevation of the soil surface. Such variations define the soil surface microrelief, which is characterized by a high spatial variability. Soil surface roughness is a property affecting many processes such as depression storage, infiltration, sediment generation, storage and transport and runoff routing. Therefore the soil surface microrelief is a key element in hydrology and soil erosion processes at different spatial scales as for example at the plot, field or catchment scale. In agricultural land soil surface roughness is mainly created by tillage operations, which promote to different extent the formation of microdepressions and microelevations and increase infiltration and temporal retention of water. The decay of soil surface roughness has been demonstrated to be mainly driven by rain height and rain intensity, and to depend also on runoff, aggregate stability, soil reface porosity and soil surface density. Soil roughness formation and decay may be also influenced by antecedent soil moisture (either before tillage or rain), quantity and type of plant residues over the soil surface and soil composition. Characterization of the rate and intensity of soil surface roughness decay provides valuable information about the degradation of the upper most soil surface layer before soil erosion has been initiated or at the very beginning of soil runoff and erosion processes. We analyzed the rate of decay of soil surface roughness from several experiments conducted in two regions under temperate and subtropical climate and with contrasting land use systems. The data sets studied were obtained both under natural and simulated rainfall for various soil tillage and management types. Soil surface roughness decay was characterized bay several parameters, including classic and single parameters such as the random roughness or the tortuosity and parameters based on advanced geostatistical methods or on the fractal theory. Our

  13. Effect of tillage systems and permanent groundcover intercropped with orange trees on soil enzyme activities

    Directory of Open Access Journals (Sweden)

    Elcio Liborio Balota

    2011-04-01

    Full Text Available The objective of this study was to evaluate the effect of different soil tillage systems and groundcover crops intercropped with orange trees on soil enzyme activities. The experiment was performed in an Ultisol soil in northwestern Paraná State. Two soil tillage systems were evaluated [conventional tillage (CT across the entire area and strip tillage (ST with a 2-m strip width] in combination with various groundcover vegetation management systems. Soil samples were collected after five years of experimental management at a depth of 0-15 cm under the tree canopy and in the inter-row space in the following treatments: (1 CT-Calopogonium mucunoides; (2 CT-Arachis pintoi; (3 CT-Bahiagrass; (4 CT-Brachiaria humidicola; and (5 ST-B. humidicola. The soil tillage systems and groundcover crops influenced the soil enzyme activities both under the tree canopy and in the inter-row space. The cultivation of B. humidicola provided higher amylase, arylsulfatase, acid phosphatase and alkaline phosphatase than other groundcover species. Strip tillage increased enzyme activities compared to the conventional tillage system.

  14. Effect of adding phosphogypsum to the soil on the growth, yields, radionuclides, trace elements; fluorine accumulation in kochia scoparia (L) schard

    International Nuclear Information System (INIS)

    Al-Odat, M.; Al-Sharabi, N.; Kanakri, S.

    2004-01-01

    Large quantities of phosphogypsum, a by-product of phosphate fertilizer industry, are stacked close to urban areas in Syria. This may pose negative impacts on the environment. Many studies have reported positive effects of phosphogypsum application on nutrient levels and physical and chemical properties of agricultural soils. There are some concerns that the application of phosphogypsum to agricultural lands may result in the uptake by plant of radionuclides, fluorine and trace elements. Phosphogypsum, which has a radioactivity of 416 Bq/kg, was mixed with a loamy soil, at different rates (0, 10, 20 and 40 T/ha). The experiments were carried out using Kochia scoparia, as a forage crop. The results showed that adding phosphogypsum to the soil, at a rate of 10 to 40 t/ha increased significantly the yields of Kochia by 44%. The radioactivities in the shoot systems of Kochia grown on these soil - phosphogypsum mixtures were below detection level. In addition, phosphogypsum application did not cause accumulation of trace elements in the soil or plant. Fluorine concentrations in the forage increased but remained less than the allowable level (30 ppm.). Therefore adding phosphogypsum to agricultural soils (at a rate of 10-20 T/ha) can be considered an effective way of improving soil properties, crop productivity and represents a way of phosphogypsum utilization which reduces negative effects on the environment. (author)

  15. Production planning and control of less emitting production systems

    Energy Technology Data Exchange (ETDEWEB)

    Haasis, H.D. [Bremen Univ. (Germany)

    1995-12-31

    The concept of integral environmental protection has been growing in importance within Western Europe in recent years. Increasingly, it has come to be recognized that no one part of the environment is separate from any other, it functions as a whole. Yet, pollution control was until recently, usually based on an approach which considers emissions to air, water, and land separately. That has begun to change, particularly since the 1987 report by the World Commission on Environment and Development. This can be recognized, for example, within the proposal for a Directive of the Council of the European Union on Integrated Pollution Prevention and Control. By this, the environmental media are placed on an equal legislative footing so that the final result will be that the way in which an installation is operated will be better for the whole environment. In other words, less emission production systems are obtained. Realization of an integral concept or of less emission production systems initially requires technical measures for the avoidance and the minimization of emissions, as well as recovery and recycling of materials and substances

  16. Production planning and control of less emitting production systems

    Energy Technology Data Exchange (ETDEWEB)

    Haasis, H D [Bremen Univ. (Germany)

    1996-12-31

    The concept of integral environmental protection has been growing in importance within Western Europe in recent years. Increasingly, it has come to be recognized that no one part of the environment is separate from any other, it functions as a whole. Yet, pollution control was until recently, usually based on an approach which considers emissions to air, water, and land separately. That has begun to change, particularly since the 1987 report by the World Commission on Environment and Development. This can be recognized, for example, within the proposal for a Directive of the Council of the European Union on Integrated Pollution Prevention and Control. By this, the environmental media are placed on an equal legislative footing so that the final result will be that the way in which an installation is operated will be better for the whole environment. In other words, less emission production systems are obtained. Realization of an integral concept or of less emission production systems initially requires technical measures for the avoidance and the minimization of emissions, as well as recovery and recycling of materials and substances

  17. Soil quality assessment in rice production systems: establishing a minimum data set.

    NARCIS (Netherlands)

    Rodrigues de Lima, A.C.; Hoogmoed, W.B.; Brussaard, L.

    2008-01-01

    Soil quality, as a measure of the soil's capacity to function, can be assessed by indicators based on physical, chemical, and biological properties. Here we report on the assessment of soil quality in 21 rice (Oryza sativa) fields under three rice production systems (semi-direct, pre-germinated, and

  18. Mechanical impedance of soil crusts and water content in loamy soils

    Science.gov (United States)

    Josa March, Ramon; Verdú, Antoni M. C.; Mas, Maria Teresa

    2013-04-01

    Soil crust development affects soil water dynamics and soil aeration. Soil crusts act as mechanical barriers to fluid flow and, as their mechanical impedance increases with drying, they also become obstacles to seedling emergence. As a consequence, the emergence of seedling cohorts (sensitive seeds) might be reduced. However, this may be of interest to be used as an effective system of weed control. Soil crusting is determined by several factors: soil texture, rain intensity, sedimentation processes, etc. There are different ways to characterize the crusts. One of them is to measure their mechanical impedance (MI), which is linked to their moisture level. In this study, we measured the evolution of the mechanical impedance of crusts formed by three loamy soil types (clay loam, loam and sandy clay loam, USDA) with different soil water contents. The aim of this communication was to establish a mathematical relationship between the crust water content and its MI. A saturated soil paste was prepared and placed in PVC cylinders (50 mm diameter and 10 mm height) arranged on a plastic tray. Previously the plastic tray was sprayed with a hydrophobic liquid to prevent the adherence of samples. The samples on the plastic tray were left to air-dry under laboratory conditions until their IM was measured. To measure IM, a food texture analyzer was used. The equipment incorporates a mobile arm, a load cell to apply force and a probe. The arm moves down vertically at a constant rate and the cylindrical steel probe (4 mm diameter) penetrates the soil sample vertically at a constant rate. The equipment is provided with software to store data (time, vertical distance and force values) at a rate of up to 500 points per second. Water content in crust soil samples was determined as the loss of weight after oven-drying (105°C). From the results, an exponential regression between MI and the water content was obtained (determination coefficient very close to 1). This methodology allows

  19. Closed Ecological Life Support Systems (CELSS) Test Facility

    Science.gov (United States)

    Macelroy, Robert D.

    1992-01-01

    The CELSS Test Facility (CTF) is being developed for installation on Space Station Freedom (SSF) in August 1999. It is designed to conduct experiments that will determine the effects of microgravity on the productivity of higher (crop) plants. The CTF will occupy two standard SSF racks and will accommodate approximately one square meter of growing area and a canopy height of 80 cm. The growth volume will be isolated from the external environment, allowing stringent control of environmental conditions. Temperature, humidity, oxygen, carbon dioxide, and light levels will all be closely controlled to prescribed set points and monitored. This level of environmental control is needed to prevent stress and allow accurate assessment of microgravity effect (10-3 to 10-6 x g). Photosynthetic rates and respiration rates, calculated through continuous recording of gas concentrations, transpiration, and total and edible biomass produced will be measured. Toxic byproducts will be monitored and scrubbed. Transpiration water will be collected within the chamber and recycled into the nutrient solution. A wide variety of crop plants, e.g., wheat, soy beans, lettuce, potatoes, can be accommodated and various nutrient delivery systems and light delivery systems will be available. In the course of its development, the CTF will exploit fully, and contribute importantly, to the state-of-art in closed system technology and plant physiology.

  20. Surface EEG-Transcranial Direct Current Stimulation (tDCS) Closed-Loop System.

    Science.gov (United States)

    Leite, Jorge; Morales-Quezada, Leon; Carvalho, Sandra; Thibaut, Aurore; Doruk, Deniz; Chen, Chiun-Fan; Schachter, Steven C; Rotenberg, Alexander; Fregni, Felipe

    2017-09-01

    Conventional transcranial direct current stimulation (tDCS) protocols rely on applying electrical current at a fixed intensity and duration without using surrogate markers to direct the interventions. This has led to some mixed results; especially because tDCS induced effects may vary depending on the ongoing level of brain activity. Therefore, the objective of this preliminary study was to assess the feasibility of an EEG-triggered tDCS system based on EEG online analysis of its frequency bands. Six healthy volunteers were randomized to participate in a double-blind sham-controlled crossover design to receive a single session of 10[Formula: see text]min 2[Formula: see text]mA cathodal and sham tDCS. tDCS trigger controller was based upon an algorithm designed to detect an increase in the relative beta power of more than 200%, accompanied by a decrease of 50% or more in the relative alpha power, based on baseline EEG recordings. EEG-tDCS closed-loop-system was able to detect the predefined EEG magnitude deviation and successfully triggered the stimulation in all participants. This preliminary study represents a proof-of-concept for the development of an EEG-tDCS closed-loop system in humans. We discuss and review here different methods of closed loop system that can be considered and potential clinical applications of such system.

  1. Soil Properties and Plant Biomass Production in Natural Rangeland Management Systems

    Directory of Open Access Journals (Sweden)

    Romeu de Souza Werner

    Full Text Available ABSTRACT Improper management of rangelands can cause land degradation and reduce the economic efficiency of livestock activity. The aim of this study was to evaluate soil properties and quantify plant biomass production in four natural rangeland management systems in the Santa Catarina Plateau (Planalto Catarinense of Brazil. The treatments, which included mowed natural rangeland (NR, burned natural rangeland (BR, natural rangeland improved through the introduction of plant species after harrowing (IH, and natural rangeland improved through the introduction of plant species after chisel plowing (IC, were evaluated in a Nitossolo Bruno (Nitisol. In the improved treatments, soil acidity was corrected, phosphate fertilizer was applied, and intercropped annual ryegrass (Lolium multiflorum, velvet grass (Holcus lanatus, and white clover (Trifolium repens were sown. Management systems with harrowed or chisel plowed soil showed improved soil physical properties; however, the effect decreased over time and values approached those of burned and mowed natural rangelands. Natural rangeland systems in the establishment phase had little influence on soil organic C. The mowed natural rangeland and improved natural rangeland exhibited greater production of grazing material, while burning the field decreased production and increased the proportion of weeds. Improvement of the natural rangelands increased leguminous biomass for pasture.

  2. Simply obtained global radiation, soil temperature and soil moisture in an alley cropping system in semi-arid Kenya

    NARCIS (Netherlands)

    Mungai, D.N.; Stigter, C.J.; Coulson, C.L.; Ng'ang'a, J.K.

    2000-01-01

    Global radiation, soil temperature and soil moisture data were obtained from a 4-6 year old Cassia siamea/maize (CM) alley cropping (or hedgerow intercropping) system, at a semi-arid site at Machakos, Kenya, in the late eighties. With the growing need to explore and manage variations in

  3. Aggregates morphometry in a Latosol (Oxisol under different soil management systems

    Directory of Open Access Journals (Sweden)

    Carla Eloize Carducci

    2016-02-01

    Full Text Available Changes in soil physical properties are inherent in land use, mainly in superficial layers. Structural alterations can directly influence distribution, stability and especially morphometry of soil aggregates, which hence will affect pore system and the dynamic process of water and air in soil. Among the methods used to measure these changes, morphometry is a complementary tool to the classic methods. The aim of this study was to evaluate structural quality of a Latosol (Oxisol, under different management systems, using morphometric techniques. Treatments consisted of soil under no-tillage (NT; pasture (P, in which both had been cultivated for ten years, and an area under native vegetation (NV – Savannah like vegetation. Aggregates were sampled at depths of 0-0.10 and 0.10-0.20 m, retained on sieves with 9.52 – 4.76 mm, 4.76 – 1.0mm, 1.0 – 0.5mm diameter ranges. Aggregate morphometry was assessed by 2D images from scanner via QUANTPORO software. The analyzed variables were: area, perimeter, aspect, roughness, Ferret diameter and compactness. Moreover, disturbed samples were collected at the same depths to determine particle size, aggregate stability in water, water-dispersible clay, clay flocculation index and organic matter content. It was observed that different soil management systems have modified soil aggregate morphology as well as physical attributes; and management effects’ magnitude increased from NT to P.

  4. Sustainable Soil Water Management Systems

    OpenAIRE

    Basch, G.; Kassam, A.; Friedrich, T.; Santos, F.L.; Gubiani, P.I.; Calegari, A.; Reichert, J.M.; dos Santos, D.R.

    2012-01-01

    Soil quality and its management must be considered as key elements for an effective management of water resources, given that the hydrological cycle and land management are intimately linked (Bossio et al. 2007). Soil degradation has been described by Bossio et al. (2010) as the starting point of a negative cycle of soil-water relationships, creating a positive, self-accelerating feedback loop with important negative impacts on water cycling and water productivity. Therefore, sustainable soil...

  5. Ecological risk evaluation of polluted soils from Sasa mineral processing concentrator

    OpenAIRE

    Krstev, Boris; Golomeov, Blagoj; Golomeova, Mirjana; Krstev, Aleksandar

    2007-01-01

    The idea that the earth is a closed system and that soil, like other mediums, is polluted by human activities, is very recent, hardly thirty years old. The chief preoccupation has been with water pollution, a conviction that, sooner or later, all the pollutants found in water were the principal cause of the emergence of aquatic ecotoxicology. Yet, the existence of polluted soils has been cited since ancient times. Greek and Roman writers remarked that the contamination of water and air near m...

  6. Biological Treatment of Petroleum in Radiologically Contaminated Soil

    Energy Technology Data Exchange (ETDEWEB)

    BERRY, CHRISTOPHER

    2005-11-14

    This chapter describes ex situ bioremediation of the petroleum portion of radiologically co-contaminated soils using microorganisms isolated from a waste site and innovative bioreactor technology. Microorganisms first isolated and screened in the laboratory for bioremediation of petroleum were eventually used to treat soils in a bioreactor. The bioreactor treated soils contaminated with over 20,000 mg/kg total petroleum hydrocarbon and reduced the levels to less than 100 mg/kg in 22 months. After treatment, the soils were permanently disposed as low-level radiological waste. The petroleum and radiologically contaminated soil (PRCS) bioreactor operated using bioventing to control the supply of oxygen (air) to the soil being treated. The system treated 3.67 tons of PCRS amended with weathered compost, ammonium nitrate, fertilizer, and water. In addition, a consortium of microbes (patent pending) isolated at the Savannah River National Laboratory from a petroleum-contaminated site was added to the PRCS system. During operation, degradation of petroleum waste was accounted for through monitoring of carbon dioxide levels in the system effluent. The project demonstrated that co-contaminated soils could be successfully treated through bioventing and bioaugmentation to remove petroleum contamination to levels below 100 mg/kg while protecting workers and the environment from radiological contamination.

  7. Use of neutron scattering meter to detect soil moisture distribution under trickle irrigation system in sandy soil of inshas, Egypt

    International Nuclear Information System (INIS)

    Abd El-moniem, M.; El-gendy, R.W.; Gadalla, A.M.; Hamdy, A.; Zeedan, A.

    2006-01-01

    This study aims to investigate the soil moisture distribution under different quantities of irrigation water in cultivated sandy soil with squash, using drip irrigation system. This study was carried out in Inshas sandy soil at the farm of Soil and Water Research Department, Nuclear Research Centre, Atomic Energy Authority, Egypt. Three rates of applied irrigation water (100, 75 and 50 % ETc) were used. Three sites (0, 12.5 and 25 cm distances from the emitter between drippers and laterals lines) were chosen to measure soil moisture contents (horizontal and vertical directions within the soil depths). The obtained data pointed out that the maximum width, in onion shape of water distribution under drip irrigation system, was at 45 cm depth at 0 site. From the study of soil moisture distribution, the overlapping between each two neighbor drippers played a good role in increasing soil moisture content at the 25 site rather than the rest sites. Water distribution was affected with plant location within the wet area as well as the used irrigation water quantities. Water distribution between drippers and laterals did not differ much approximately. The highest soil moisture depletion was at 12.5 site (between drippers) for 100 and 75 % ETc rather than the rest treatments. 100 % ETc treatment introduced the highest soil moisture depletion in the first stage of plant growth season for the three sites (between drippers and laterals). In the last stage of plant growth season, water re-distribution phenomena resulted from the changeable total hydraulic potential, which played important role for interpretation of results

  8. Potential Nitrification and Nitrogen Mineral of Soil in Coffee Agroforestry System with Various Shading Trees

    Directory of Open Access Journals (Sweden)

    Purwanto .

    2007-05-01

    Full Text Available The role of shading trees in coffee farms has been well understood to establish suitable condition for the growth of coffee trees, on the other hand their role in nitrogen cycle in coffee farming is not yet well understood. The objectives of this study are to investigate the influence of various legume shading trees on the concentration of soil mineral N (N-NH4 + and N-NO3-, potential nitrification and to study the controlling factors of nitrification under field conditions. This field explorative research was carried out in Sumberjaya, West Lampung. Twelve observation plots covered four land use systems (LUS, i.e. 1 Coffee agroforestry with Gliricidiasepium as shade trees; 2 Coffee agroforestry with Gliricidiaas shade trees and Arachis pintoias cover crops; 3Coffee agroforestry with Paraserianthes falcataria as shade trees; and 4 Mixed/multistrata coffee agroforestry with Gliricidiaand other fruit crops as shade trees. Measurements of soil mineral-N concentration were carried out every three weeks for three months. Results showed that shade tree species in coffee agroforestry significantly affected concentrations of soil NH4 +, NO3- and potential nitrification. Mixed coffee agroforestry had the highest NH4+/N-mineral ratio (7.16% and the lowest potential nitrification (0.13 mg NO2-kg-1 hour -1 compared to other coffee agroforestry systems using single species of leguminous shade trees. Ratio of NH4 + /N-mineral increased 0.8—21% while potential nitrification decreased 55—79% in mixed coffee agroforestry compared to coffee agroforestry with Gliricidia or P. falcatariaas shade trees. Coffee agroforestry with P. falcatariaas shade trees had potential nitrification 53% lower and ratio of NH4 + /N-mineral concentration 20% higher than that with Gliricidia. Coffee agroforestry with P. falcataria as shade trees also had organic C content 17% higher, total N 40% higher, available P 112% higher than that with Gliricidia. The presence of A. pintoiin

  9. Effects of Cover Crops on the Movement and Fate of Soil-Applied 14C-Fonofos in a Soil-Plant-Water Microcosm

    International Nuclear Information System (INIS)

    Liang, T.T.; Lichtenstein, E.P.

    1981-01-01

    Full text: The effects of corn plants or a ''lawn'' of ryegrass on the movement and metabolism of soil-applied 14 C-(ring)-fonofos were studied in a microcosm which consisted of terrestrial and aquatic components. Artificial rain, applied to the fallow or plant covered soils, resulted in runoff that accumulated in aquaria containing lake bottom mud and aquatic organisms. The presence and the type of a cover crop had a considerable effect on the mobility and metabolism of soil—applied 14 C—fonofos. The insecticide plus its metabolites were least persistent in systems with fallow soils and most persistent in those with ryegrass. Within the terrestrial soil 14 C-compounds moved downwards and were also translocated via the root systems into the leaves of corn and ryegrass. Within the plant tops 86% of the recovered benzene—soluble 14 C-compounds were in the form of the detoxified methyl phenyl sulfone and 2% or less as fonofos. Rain caused a considerable runoff of fallow soil but much less of cropped soil into the aquaria. 14 C-compounds transported were primarily associated with the runoff soil and most of these were later found in the soil—lake mud sediments. 14 C—fonofos was the major constituent in soils and aquatic sediments while the major metabolite recovered from both the terrestrial and aquatic portion of the microcosm was methyl phenyl sulfone, its amounts ranging from 13% to 92% of all benzene—soluble radiocarbon. Relatively small amounts of the insecticidal oxygen analog of fonofos were recovered, the exception being in roots of corn and of ryegrass. (author)

  10. Root Parameters Show How Management Alters Resource Distribution and Soil Quality in Conventional and Low-Input Cropping Systems in Central Iowa.

    Directory of Open Access Journals (Sweden)

    Patricia A Lazicki

    Full Text Available Plant-soil relations may explain why low-external input (LEI diversified cropping systems are more efficient than their conventional counterparts. This work sought to identify links between management practices, soil quality changes, and root responses in a long-term cropping systems experiment in Iowa where grain yields of 3-year and 4-year LEI rotations have matched or exceeded yield achieved by a 2-year maize (Zea mays L. and soybean (Glycine max L. rotation. The 2-year system was conventionally managed and chisel-ploughed, whereas the 3-year and 4-year systems received plant residues and animal manures and were periodically moldboard ploughed. We expected changes in soil quality to be driven by organic matter inputs, and root growth to reflect spatial and temporal fluctuations in soil quality resulting from those additions. We constructed a carbon budget and measured soil quality indicators (SQIs and rooting characteristics using samples taken from two depths of all crop-phases of each rotation system on multiple dates. Stocks of particulate organic matter carbon (POM-C and potentially mineralizable nitrogen (PMN were greater and more evenly distributed in the LEI than conventional systems. Organic C inputs, which were 58% and 36% greater in the 3-year rotation than in the 4-year and 2-year rotations, respectively, did not account for differences in SQI abundance or distribution. Surprisingly, SQIs did not vary with crop-phase or date. All biochemical SQIs were more stratified (p<0.001 in the conventionally-managed soils. While POM-C and PMN in the top 10 cm were similar in all three systems, stocks in the 10-20 cm depth of the conventional system were less than half the size of those found in the LEI systems. This distribution was mirrored by maize root length density, which was also concentrated in the top 10 cm of the conventionally managed plots and evenly distributed between depths in the LEI systems. The plow-down of organic amendments

  11. Nitrogen Effects on Organic Dynamics and Soil Communities in Forest and Agricultural Systems

    Science.gov (United States)

    Grandy, S.; Neff, J.; Sinsabaugh, B.; Wickings, K.

    2008-12-01

    Human activities have doubled the global flux of biologically available N to terrestrial ecosystems but the effects of N on soil organic matter dynamics and soil communities remain difficult to predict. We examined soil organic matter chemistry and enzyme kinetics in three soil fractions (>250, 63-250, and pyrolysis-gas chromatography/mass spectroscopy, we found striking, ecosystem-specific effects of N deposition on carbohydrate abundance. Furfural, the dominant pyrolysis product of polysaccharides, was significantly decreased by simulated N deposition in the sugar maple/basswood system (15.87 versus 4.99%) but increased by N in the black oak/white oak system (8.83 versus 24.01%). There were ca. 3-fold increases in the ratio of total lignin derivatives to total polysaccharides in the >250 μm fraction of the sugar maple/basswood system but there were no changes in other size classes or in the black oak/white oak system. We also measured significant increases in the ratio of lignin derivatives to N-bearing compounds in the 63-250 and >250 μm fractions in both ecosystems but not in the corn-based cropping system. Our results demonstrate that changes in soil organic matter chemistry resulting from atmospheric N deposition or fertilization are directly linked to variation in enzyme responses to increased N availability across ecosystems and soil size fractions.

  12. Closed and Open Loop Subspace System Identification of the Kalman Filter

    Directory of Open Access Journals (Sweden)

    David Di Ruscio

    2009-04-01

    Full Text Available Some methods for consistent closed loop subspace system identification presented in the literature are analyzed and compared to a recently published subspace algorithm for both open as well as for closed loop data, the DSR_e algorithm. Some new variants of this algorithm are presented and discussed. Simulation experiments are included in order to illustrate if the algorithms are variance efficient or not.

  13. Soil, a sponge for pollutants

    OpenAIRE

    Lichtfouse , Eric

    1997-01-01

    This article is written both in English and French; International audience; This preface of the special issue entitled "Soil Pollutants" (Analusis Magazine 25, M16-M72, 1997) highlights major basic and applied issues about the sources and fate of organic, mineral and radioactive pollutants in soils. Soils have long been considered as a closed and inert medium where wastes can be dumped without impact on living organisms. This is false and we know now that soils play a vital role in ecosystems...

  14. 15N isotopic techniques to study nitrogen cycle in soil-plant-atmosphere system

    International Nuclear Information System (INIS)

    Kumar, Manoj; Chandrakala, J.U.; Sachdev, M.S.; Sachdev, P.

    2009-01-01

    Intensification of agriculture to meet the increasing food demand has caused severe disruption in natural balance of global as well as regional nitrogen cycle, potentially threatening the future sustainability of agriculture and environment of the total fertilizer nitrogen used in agriculture globally, only less than half is recovered by crop plants, rest is lost to the environment, resulting in several environmental problems such as ground water pollution and global warming, besides huge economic loss of this costly input in agriculture. Improving fertilizer nitrogen use efficiency and minimising N loss to the environment is the key to regain the lost control of nitrogen cycle in agriculture. Fertilizer nitrogen use efficiency depends largely on N requirement of crops, N supply from soil and fertilizer through N transformations in soil, and N losses from the soil-water-plant system. 15 N isotopic techniques have the potential to provide accurate measurement quantification of different processes involved in N cycle such as fixation of atmospheric N 2 , transformations- mineralization and immobilization- of soil and fertilizer N which governs N supply to plants, and N losses to the environment through ammonia volatilization, denitrification and nitrate leaching. 15 N tracers can also give precise identification of ways and sources of N loss from agriculture. These information can be used to develop strategies for increasing fertilizer N use efficiency and minimizing the loss of this costly input from agriculture to environment, which in turn will help to achieve the tripartite goal of food security, agricultural profitability and environmental quality. (author)

  15. Soil water status under perennial and annual pastures on an acid duplex soil

    International Nuclear Information System (INIS)

    Heng, L.K.; White, R.E.; Chen, D.

    2000-01-01

    A comprehensive field study of soil water balance, nitrogen (N) cycling, pasture management and animal production was carried out on an acid duplex soil at Book Book near Wagga Wagga in southern New South Wales. The experiment, carried out over a 3-year period, tested the hypothesis that sown perennial grass pastures improve the sustainability of a grazing system through better use of water and N. The treatments were: annual pastures without lime (AP-), annual pastures with lime (AP+), perennial pastures without lime (PP-) and perennial pastures with lime (PP+). Soil water measurement was made using a neutron probe on one set of the treatments comprising four adjacent paddocks. Over three winter and spring periods, the results showed that perennial grass pastures, especially PP+, consistently extracted about 40 mm more soil water each year than did the annual grass pastures. As a result, surface runoff, sub-surface flow and deep drainage (percolation below 180 cm depth) were about 40 mm less from the perennial pastures. The soil water status of the four pasture treatments was simulated reasonably well using a simple soil water model. Together with the long-term simulation of deep drainage, using past meteorological records, it is shown that proper management of perennial pastures can reduce recharge to groundwater and make pastoral systems more sustainable in the high rainfall zone. However, to completely reduce recharge, more-deeply rooted plants or trees are needed. (author)

  16. Electrochemical characterization of corrosion in materials of grounding systems, simulating conditions of synthetic soils with characteristics of local soils

    Science.gov (United States)

    Salas, Y.; Guerrero, L.; Vera-Monroy, S. P.; Blanco, J.; Jimenez, C.

    2017-12-01

    The integrity of structures buried in earthing becomes relevant when analysing maintenance and replacement costs of these systems, as the deterioration is mainly due to two factors, namely: the failures caused in the electrical systems, which are due to the system. Failure in earthing due to corrosion at the interface cause an alteration in the structure of the component material and generates an undesirable resistivity that cause malfunction in this type of protection systems. Two local soils were chosen that were categorized as sandy loam and clay loam type, whose chemical characteristics were simulated by means of an electrolyte corresponding to the amount of ions present determined by a soil characterization based on the CICE (effective cation exchange coefficient), which allows us to deduce the percentage of chloride and sulphate ions present for the different levels established in the experimental matrix. The interaction of these soils with grounding electrodes is a complex problem involving many factors to consider. In this study, the rates and corrosion currents of the different soils on two types of electrodes, one copper and the other AISI 304 stainless steel, were approximated by electrochemical techniques such as potentiodynamic curves and electrochemical impedance spectra. Considerably higher speeds were determined for copper-type electrodes when compared to those based on steel. However, from the Nyquist diagrams, it was noted that copper electrodes have better electrical performance than steel ones. The soil with the highest ionic activity turned out to be the sandy loam. The clay loam soil presents a tendency to water retention and this may be the reason for the different behaviour with respect to ionic mobility. The diffusion control in the steel seems to alter the ionic mobility because its corrosion rates proved to be very similar regardless of the type of soil chemistry. In general, corrosion rates fell since tenths of a millimetre every year to

  17. Customizing Laboratory Information Systems: Closing the Functionality Gap.

    Science.gov (United States)

    Gershkovich, Peter; Sinard, John H

    2015-09-01

    Highly customizable laboratory information systems help to address great variations in laboratory workflows, typical in Pathology. Often, however, built-in customization tools are not sufficient to add all of the desired functionality and improve systems interoperability. Emerging technologies and advances in medicine often create a void in functionality that we call a functionality gap. These gaps have distinct characteristics—a persuasive need to change the way a pathology group operates, the general availability of technology to address the missing functionality, the absence of this technology from your laboratory information system, and inability of built-in customization tools to address it. We emphasize the pervasive nature of these gaps, the role of pathology informatics in closing them, and suggest methods on how to achieve that. We found that a large number of the papers in the Journal of Pathology Informatics are concerned with these functionality gaps, and an even larger proportion of electronic posters and abstracts presented at the Pathology Informatics Summit conference each year deal directly with these unmet needs in pathology practice. A rapid, continuous, and sustainable approach to closing these gaps is critical for Pathology to provide the highest quality of care, adopt new technologies, and meet regulatory and financial challenges. The key element of successfully addressing functionality gaps is gap ownership—the ability to control the entire pathology information infrastructure with access to complementary systems and components. In addition, software developers with detailed domain expertise, equipped with right tools and methodology can effectively address these needs as they emerge.

  18. Role of soil micro-organisms in the sorption of radionuclides in organic systems

    International Nuclear Information System (INIS)

    Parekh, N.R.; Potter, E.D.; Poskitt, J.M.; Dodd, B.A.; Sanchez, A.

    2004-01-01

    Although the fraction of radionuclides linked to soil organic matter and soil microorganisms may be relatively small when compared to the amount bound to the mineral constituents, (mostly irreversibly bound), this fraction is of great importance as it remains readily exchangeable and is thus available for plant uptake. Many studies have measured the uptake of radionuclides by organic soils but the role of soil micro-organisms may have been masked by the presence of even small amounts of clay minerals occurring in these soils. We have carried out a series of experiments using a biologically active, 'mineral-free' organic soil produced under laboratory conditions, to determine the potential of soil micro-organisms to accumulate radionuclides Cs-134 and Sr-85. Biological uptake and release was differentiated from abiotic processes by comparing experimental results with inoculated and non-inoculated sterile organic material. We have investigated the role of different clay minerals, competing potassium and calcium ions, and changes in temperature on the sorption of Cs and Sr isotopes. The results from studies so far show conclusively that living components of soil systems are of primary importance in the uptake of radionuclides in organic material, microorganisms also influence the importance of chemical factors (e.g. adsorption to clay minerals) which may play a secondary role in these highly organic systems. In further experiments we hope to define the precise role of specific soil micro-organisms in these organic systems. (author)

  19. Soil carbon storage in silvopasture and related land-use systems in the brazilian cerrado.

    Science.gov (United States)

    Tonucci, Rafael G; Nair, P K Ramachandran; Nair, Vimala D; Garcia, Rasmo; Bernardino, Fernando S

    2011-01-01

    Silvopastoral management of fast-growing tree plantations is becoming popular in the Brazilian Cerrado (savanna). To understand the influence of such systems on soil carbon (C) storage, we studied C content in three aggregate size classes in six land-use systems (LUS) on Oxisols in Minas Gerais, Brazil. The systems were a native forest, a treeless pasture, 24- and 4-yr-old eucalyptus ( sp.) plantations, and 15- and 4-yr-old silvopastures of fodder grass plus animals under eucalyptus. From each system, replicated soil samples were collected from four depths (0-10, 10-20, 20-50, and 50-100 cm), fractionated into 2000- to 250-, 250- to 53-, and <53-μm size classes representing macroaggregates, microaggregates, and silt + clay, respectively, and their C contents determined. Macroaggregate was the predominant size fraction under all LUS, especially in the surface soil layers of tree-based systems. In general, C concentrations (g kg soil) in the different aggregate size fractions did not vary within the same depth. The soil organic carbon (SOC) stock (Mg C ha) to 1-m depth was highest under pasture compared with other LUS owing to its higher soil bulk density. The soils under all LUS had higher C stock compared with other reported values for managed tropical ecosystems: down to 1 m, total SOC stock values ranged from 461 Mg ha under pasture to 393 Mg ha under old eucalyptus. Considering the possibility for formation and retention of microaggregates within macroggregates in low management-intensive systems such as silvopasture, the macroaggregate dynamics in the soil seem to be a good indicator of its C storage potential. American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.

  20. Transition from closed system to Internet of Things: A study in standardizing building lighting systems

    NARCIS (Netherlands)

    Mathews, E.; Muller, G.

    2016-01-01

    Internet of Things (IoT) is triggering changes in lighting industry from the traditional closed and propriety systems to flexible, interoperable and service oriented systems. To address the challenges of this transition and catering the specific requirements of lighting networks, an Open

  1. Experimental analysis of CO2 emissions from agricultural soils subjected to five different tillage systems in Lithuania

    International Nuclear Information System (INIS)

    Buragienė, Sidona; Šarauskis, Egidijus; Romaneckas, Kęstutis; Sasnauskienė, Jurgita; Masilionytė, Laura; Kriaučiūnienė, Zita

    2015-01-01

    Intensive agricultural production strongly influences the global processes that determine climate change. Thus, tillage can play a very important role in climate change. The intensity of soil carbon dioxide (CO 2 ) emissions, which contribute to the greenhouse effect, can vary depending on the following factors: the tillage system used, meteorological conditions (which vary in different regions of the world), soil properties, plant residue characteristics and other factors. The main purpose of this research was to analyse and assess the effects of autumn tillage systems with different intensities on CO 2 emissions from soils during different seasons and under the climatic conditions of Central Lithuania. The research was conducted at the Experimental Station of Aleksandras Stulginskis University from 2009 to2012; and in 2014. The soils at the experimental site were classified as Eutric Endogleyic Planosol (Drainic). The investigations were conducted using five tillage systems with different intensities, typical of the Baltic Region. Deep conventional ploughing was performed at a depth of 230–250 mm, shallow ploughing was conducted at a depth of 120–150 mm, deep loosening was conducted at depths of 250–270 mm, and shallow loosening was conducted at depths of 120–150 mm. The fifth system was a no-tillage system. Overall, autumn tillage resulted in greater CO 2 emissions from the soil over both short- and long-term periods under the climatic conditions of Central Lithuania, regardless of the tillage system applied. The highest soil CO 2 emissions were observed for the conventional deep ploughing tillage system, and the lowest emissions were observed for the no-tillage system. The meteorological conditions greatly influenced the CO 2 emissions from the soil during the spring. Soil CO 2 emissions were enhanced as precipitation and the air and soil temperatures increased. Long-term investigations regarding the dynamics of CO 2 emissions from soils during the

  2. Carbon dioxide dynamics of combined crops of wheat, cowpea, pinto beans in the Laboratory Biosphere closed ecological system

    Science.gov (United States)

    Dempster, William F.; Nelson, M.; Silverstone, S.; Allen, J. P.

    2009-04-01

    A mixed crop consisting of cowpeas, pinto beans and Apogee ultra-dwarf wheat was grown in the Laboratory Biosphere, a 40 m 3 closed life system equipped with 12,000 W of high pressure sodium lamps over planting beds with 5.37 m 2 of soil. Similar to earlier reported experiments, the concentration of carbon dioxide initially increased to 7860 ppm at 10 days after planting due to soil respiration plus CO 2 contributed from researchers breathing while in the chamber for brief periods before plant growth became substantial. Carbon dioxide concentrations then fell rapidly as plant growth increased up to 29 days after planting and subsequently was maintained mostly in the range of about 200-3000 ppm (with a few excursions) by CO 2 injections to feed plant growth. Numerous analyses of rate of change of CO 2 concentration at many different concentrations and at many different days after planting reveal a strong dependence of fixation rates on CO 2 concentration. In the middle period of growth (days 31-61), fixation rates doubled for CO 2 at 450 ppm compared to 270 ppm, doubled again at 1000 ppm and increased a further 50% at 2000 ppm. High productivity from these crops and the increase of fixation rates with elevated CO 2 concentration supports the concept that enhanced CO 2 can be a useful strategy for remote life support systems. The data suggests avenues of investigation to understand the response of plant communities to increasing CO 2 concentrations in the Earth's atmosphere. Carbon balance accounting and evapotranspiration rates are included.

  3. Development of methods for remediation of artificial polluted soils and improvement of soils for ecologically clean agricultural production systems

    International Nuclear Information System (INIS)

    Bogachev, V.; Adrianova, G.; Zaitzev, V.; Kalinin, V.; Kovalenko, E.; Makeev, A.; Malikova, L.; Popov, Yu.; Savenkov, A.; Shnyakina, V.

    1996-01-01

    The purpose of the research: Development of methods for the remediation of artificial polluted soils and the improvement of polluted lands to ecologically clean agricultural production.The following tasks will be implemented in this project to achieve viable practical solutions: - To determine the priority pollutants, their ecological pathways, and sources of origin. - To form a supervised environmental monitoring data bank throughout the various geo system conditions. - To evaluate the degree of the bio geo system pollution and the influence on the health of the local human populations. - To establish agricultural plant tolerance levels to the priority pollutants. - To calculate the standard concentrations of the priority pollutants for main agricultural plant groups. - To develop a soil remediation methodology incorporating the structural, functional geo system features. - To establish a territory zone division methodology in consideration of the degree of component pollution, plant tolerance to pollutants, plant production conditions, and human health. - Scientific grounding of the soil remediation proposals and agricultural plant material introductions with soil pollution levels and relative plant tolerances to pollutants. Technological Means, Methods, and Approaches Final proposed solutions will be based upon geo system and ecosystem approaches and methodologies. The complex ecological valuation methods of the polluted territories will be used in this investigation. Also, laboratory culture in vitro, application work, and multi-factor field experiments will be conducted. The results will be statistically analyzed using appropriate methods. Expected Results Complex biogeochemical artificial province assessment according to primary pollutant concentrations. Development of agricultural plant tolerance levels relative to the priority pollutants. Assessment of newly introduced plant materials that may possess variable levels of pollution tolerance. Remediation

  4. Soil Erosion and Agricultural Sustainability

    Science.gov (United States)

    Montgomery, D. R.

    2009-04-01

    Data drawn from a global compilation of studies support the long articulated contention that erosion rates from conventionally plowed agricultural fields greatly exceed rates of soil production, erosion under native vegetation, and long-term geological erosion. Whereas data compiled from around the world show that soil erosion under conventional agriculture exceeds both rates of soil production and geological erosion rates by up to several orders of magnitude, similar global distributions of soil production and geological erosion rates suggest an approximate balance. Net soil erosion rates in conventionally plowed fields on the order of 1 mm/yr can erode typical hillslope soil profiles over centuries to millennia, time-scales comparable to the longevity of major civilizations. Well-documented episodes of soil loss associated with agricultural activities date back to the introduction of erosive agricultural methods in regions around the world, and stratigraphic records of accelerated anthropogenic soil erosion have been recovered from lake, fluvial, and colluvial stratigraphy, as well as truncation of soil stratigraphy (such as truncated A horizons). A broad convergence in the results from studies based on various approaches employed to study ancient soil loss and rates of downstream sedimentation implies that widespread soil loss has accompanied human agricultural intensification in examples drawn from around the world. While a broad range of factors, including climate variability and society-specific social and economic contexts — such as wars or colonial relationships — all naturally influence the longevity of human societies, the ongoing loss of topsoil inferred from studies of soil erosion rates in conventional agricultural systems has obvious long-term implications for agricultural sustainability. Consequently, modern agriculture — and therefore global society — faces a fundamental question over the upcoming centuries. Can an agricultural system

  5. 3. A Closed Aquatic System for Space and Earth Application

    Science.gov (United States)

    Slenzka, K.; Duenne, M.; Jastorff, B.; Ranke, J.; Schirmer, M.

    Increased durations in space travel as well as living in extreme environments are requiring reliable life support systems in general and bioregenerative ones in detail. Waste water management, air revitalization and food production are obviously center goals in this research, however, in addition a potential influence by chemicals, drugs etc. released to the closed environment must be considered. On this basis ecotoxicological data become more and more important for CELSS (Closed Ecological Life Support System) development and performance. The experiences gained during the last years in our research group lead to the development of an aquatic habitat, called AquaHab (formerly CBRU), which is a closed, self-sustaining system with a total water volume of 9 liters. In the frame program of a R&D project funded by the state of Bremen and OHB System, AquaHab is under adaptation to become an ecotoxicological research unit containing for example Japanese Medaka or Zebra Fish, amphipods, water snails and water plants. Test runs were standardized and analytical methods were developed. Beside general biological and water chemical parameters, activity measurements of biotransforming enzymes (G6PDH, CytP450-Oxidase, Peroxidase) and cell viability tests as well as residual analysis of the applied substance and respective metabolites were selected as evaluation criteria. In a first series of tests low doses effects of TBT (Tributyltin, 0.1 to 20 μgTBT/l nominal concentration) were analyzed. The AquaHab and data obtained for applied environmental risk assessment will be presented at the assembly.

  6. Physical separations soil washing system cold test results

    Energy Technology Data Exchange (ETDEWEB)

    McGuire, J.P.

    1993-07-28

    This test summary describes the objectives, methodology, and results of a physical separations soil-washing system setup and shakedown test using uncontaminated soil. The test is being conducted in preparation for a treatability test to be conducted in the North Pond of the 300-FF-1 Operable Unit. It will be used to assess the feasibility of using a physical separations process to reduce the volume of contaminated soils in the 300-FF-1 Operable Unit. The test is described in DOE-RL (1993). The setup test was conducted at an uncontrolled area located approximately 3.2 km northwest of the 300-FF-1 Operable Unit. The material processed was free of contamination. The physical separation equipment to be used in the test was transferred to the US Department of Energy (DOE) by the US Environmental Protection Agency (EPA) Risk Reduction Engineering Laboratory. On May 13, 1993, soil-washing equipment was moved to the cold test location. Design assistance and recommendation for operation was provided by the EPA.

  7. Microflora inside closed modules with plant growth facility

    Science.gov (United States)

    Zyablova, Natalya V.; Berkovich, Yuliy A.; Shanturin, Nikolai; Deshevaya, Elena; Smolyanina, Svetlana O.

    Currently, plant growth facility (PGF) is included in the LSS in many scenarios of Martian expedition. A number of investigators assume growing of crops can accelerate microflora re-production in closed ecological system. To estimate experimentally the change of density of microbiological community in the isolated module, Chinese cabbage Brassica hinensis L., cv. Vesnyanka, has been grown in the closed climatic chambers in volume 0.07 m3, 3 m3 and 250 m3 under continuous illumination in the range of values of temperature and relative humidity of air 23 -270 and 30 -60%, respectively. There were no differences in growth and develop-ment of plants grown during 30 days on the test-beds in the laboratory room (control) and in the closed chamber by 0.07 m3 volume (test). The microbiological analysis of root zone has revealed the presence of exclusively saprophytic species -the typical representatives of the soil microbiota. Then the plants were growing during 45 days in the prototype of the conveyor space PGF "Phytocycle LED" placed inside the chamber of 3 m3 volume. Every 3 days 50 -60 cm3 of liquid imitator of air condensate (IAC) from inhabited module had been injected to the chamber to simulate air pollution. The content of colony-forming units of the micromycetes in the air of the chamber, on the inner surfaces of the climate chamber, internal and external surfaces of the PGF and the leaves did not exceed the permissible values. When the PGF has been installed during 14 days inside the inhabited module with volume of 250 m3, the representatives of saprophytic and conditioned-pathogenic species of micromycetes (Trichethe-cium rozeum, Trichoderma sp., Fuzarrium sp., Mucor sp., Penicillium sp.) have been found out exclusively on the open surfaces of artificial soil and water-saturated porous passage. The obtained data shows that PGF inside closed modules can assure microbiological safety when all wet surfaces are isolated from the gas environment.

  8. Effect of adding phosphogypsum to the soil on the growth, yield, radionuclides, trace elements and fluorine accumulation in Kochia scoparia (L.) schrad

    International Nuclear Information System (INIS)

    Al-Odat, M.; Sharabi, N.; Kanacri, S.

    2004-01-01

    Large quantities of phosphogypsum, a by-product of phosphate fertilizer industry, are stacked close to urban areas in Syria. This may pose negative impacts on the environment. Many studies have reported positive effects of phosphogypsum application on nutrient levels, physical and chemical properties of agricultural soils. There are some concerns that the application of phosphogypsum to agricultural lands may results in the uptake by plant of radionuclides, fluorine and trace elements. Phosphogypsum, which has a radioactivity of 416 Bq/Kg, was mixed with a loamy soil, at different rates (0, 10, 20 and 40 T/ha). The experiments were carried out using Kochia scoparia, as a forage crop. The results showed that adding phosphogypsum to the soil, at a rate of 10 to 40 T/ha increased significantly the yields of Kochia by 44%. The radioactivities in the shoot systems of Kochia grown on these soil - phosphogypsum mixtures were below detection level. In addition, phosphogypsum application did not cause accumulation of trace elements in the soil or plant. Fluorine concentrations in the forage increased but remained less than the allowable level (30 ppm). Therefore adding phosphogypsum to agricultural soils (at a rate of 10-20 T/ha) can be considered an effective way of improving soil properties, crop productivity and represents a way of phosphogypsum utilization which reduces in negative effects on the environment. (author)

  9. Proper time axis of a closed relativistic system

    International Nuclear Information System (INIS)

    Chernikov, N.A.; Fadeev, N.G.; Shavokhina, N.S.

    1997-01-01

    The definition of a proper time axis of a closed relativistic system of colliding particles is given. The solution of the proper time axis problem is presented. If the light velocity c equals the imaginary unit i, then in the case of a plane motion of the system the problem about the proper time axis turns out to be equivalent to the known in engineering mechanics problem about the reduction of any system of forces, applied to a rigid body, to the dynamic screw. In the general case, when c=i, the problem about the proper time axis turns out to be equivalent to the problem about the reduction to the dynamic screw of a system of forces, applied to a rigid body in a four-dimensional Euclidean space

  10. Control technologies for soil vapor extraction at petroleum hydrocarbon impacted sites -- Regulatory challenges to system operations

    International Nuclear Information System (INIS)

    Cacossa, K.F.; Campbell, G.E.; Devine, K.

    1995-01-01

    Soil vapor extraction (SVE) is frequently used to remediate soils impacted by petroleum hydrocarbons. Four technologies have proven to be viable methods to control the off-gas emissions from SVE systems, namely, internal combustion, thermal oxidation, catalytic oxidation, and granular activated carbon adsorption. The optimal range of influent vapor concentrations for system operation differs for each of the technologies. Over the past several years the authors have worked proactively with the state regulatory community to develop general, all inclusive air pollution control permits which allow for the potential use of all four technologies over the life of the permit. Private industry has similarly worked with the state regulators to develop a less labor intensive sampling/monitoring procedure. Actual system performances, which were monitored using summa canisters and field equipment, provided the basis for the new procedure. System performance data indicated that field sampling with portable hydrocarbon analyzers, such as flame ionization detectors (FID), was preferable over the use of summa canister sampling. In addition, to reduce the costs associated with the analysis of samples, the new SVE monitoring protocol also reduced the number of system monitoring visits. These reductions equated into a cost effective, yet environmentally sound SVE system monitoring programs. Finally, the authors have worked with the regulatory community to establish permit limitations which allow operational flexibility

  11. Soil loss estimation using geographic information system in enfraz watershed for soil conservation planning in highlands of Ethiopia

    Directory of Open Access Journals (Sweden)

    Gizachew Tiruneh

    2015-12-01

    Full Text Available Accelerated soil erosion is a worldwide problem because of its economic and environmental impacts. Enfraz watershed is one of the most erosion-prone watersheds in the highlands of Ethiopia, which received little attention. This study was, therefore, carried out to spatially predict the soil loss rate of the watershed with a Geographic Information System (GIS and Remote Sensing (RS. Revised Universal Soil Loss Equation (RUSLE adapted to Ethiopian conditions was used to estimate potential soil losses by utilizing information on rainfall erosivity (R using interpolation of rainfall data, soil erodibility (K using soil map, vegetation cover (C using satellite images, topography (LS using Digital Elevation Model (DEM and conservation practices (P using satellite images. Based on the analysis, about 92.31% (5914.34 ha of the watershed was categorized none to slight class which under soil loss tolerance (SLT values ranging from 5 to 11 tons ha-1 year-1. The remaining 7.68% (492.21 ha of land was classified under moderate to high class about several times the maximum tolerable soil loss. The total and an average amount of soil loss estimated by RUSLE from the watershed was 30,836.41 ton year-1 and 4.81 tons ha-1year-1, respectively.

  12. Closed cycle electric discharge laser design investigation

    Science.gov (United States)

    Baily, P. K.; Smith, R. C.

    1978-01-01

    Closed cycle CO2 and CO electric discharge lasers were studied. An analytical investigation assessed scale-up parameters and design features for CO2, closed cycle, continuous wave, unstable resonator, electric discharge lasing systems operating in space and airborne environments. A space based CO system was also examined. The program objectives were the conceptual designs of six CO2 systems and one CO system. Three airborne CO2 designs, with one, five, and ten megawatt outputs, were produced. These designs were based upon five minute run times. Three space based CO2 designs, with the same output levels, were also produced, but based upon one year run times. In addition, a conceptual design for a one megawatt space based CO laser system was also produced. These designs include the flow loop, compressor, and heat exchanger, as well as the laser cavity itself. The designs resulted in a laser loop weight for the space based five megawatt system that is within the space shuttle capacity. For the one megawatt systems, the estimated weight of the entire system including laser loop, solar power generator, and heat radiator is less than the shuttle capacity.

  13. Feasibility of closed Fe(II)/Fe(III) system for product-reflux in Nitrox process

    International Nuclear Information System (INIS)

    Adachi, M.; Ishida, T.

    1981-01-01

    A concept of closed reflux system for stable isotope fractionation by chemical exchange method has been introduced. In a closed system a chemical agent used to convert one chemical species of an isotopic exchange reaction into the other at the product end is regenerated on site by means of an electrochemical or thermal process. It offers a convenience of eliminating the needs for transporting chemicals to and from the site and an advantage of allowing leniency in the degree of completeness of the reflux reaction. Feasibility of use of Fe(II) salt solutions in a closed reflux system for the Nitrox process for 15 N fractionation has been studied. Two of such systems, FeSO 4 in H 2 SO 4 and Fe(ClO 4 ) 2 in HClO 4 , are adopted for packed column operation. For both systems, the rate of reduction of nitric acid increases with increasing acid concentration, the solubility of the salts decreases with the increasing acid concentration, and the reflux reaction can be made to go to completion. Evaluation of such a closed reflux system will have to include that of performance of regenerative process

  14. Soil cover by natural trees in agroforestry systems

    Science.gov (United States)

    Diaz-Ambrona, C. G. H.; Almoguera Millán, C.; Tarquis Alfonso, A.

    2009-04-01

    The dehesa is common agroforestry system in the Iberian Peninsula. These open oak parklands with silvo-pastoral use cover about two million hectares. Traditionally annual pastures have been grazed by cows, sheep and also goats while acorns feed Iberian pig diet. Evergreen oak (Quercus ilex L.) has other uses as fuelwood collection and folder after tree pruning. The hypothesis of this work is that tree density and canopy depend on soil types. We using the spanish GIS called SIGPAC to download the images of dehesa in areas with different soil types. True colour images were restoring to a binary code, previously canopy colour range was selected. Soil cover by tree canopy was calculated and number of trees. Processing result was comparable to real data. With these data we have applied a dynamic simulation model Dehesa to determine evergreen oak acorn and annual pasture production. The model Dehesa is divided into five submodels: Climate, Soil, Evergreen oak, Pasture and Grazing. The first three require the inputs: (i) daily weather data (maximum and minimum temperatures, precipitation and solar radiation); (ii) the soil input parameters for three horizons (thickness, field capacity, permanent wilting point, and bulk density); and (iii) the tree characterization of the dehesa (tree density, canopy diameter and height, and diameter of the trunk). The influence of tree on pasture potential production is inversely proportional to the canopy cover. Acorn production increase with tree canopy cover until stabilizing itself, and will decrease if density becomes too high (more than 80% soil tree cover) at that point there is competition between the trees. Main driving force for dehesa productivity is soil type for pasture, and tree cover for acorn production. Highest pasture productivity was obtained on soil Dystric Planosol (Alfisol), Dystric Cambisol and Chromo-calcic-luvisol, these soils only cover 22.4% of southwest of the Iberian peninssula. Lowest productivity was

  15. Soil characterization in contrasting cropping systems under the fast ...

    African Journals Online (AJOL)

    The contrasting production systems under study were communal area, A2 (large scale resettlement) and A1 (small scale resettlement).All these systems are in Manicaland province, Zimbabwe. The A1 and A2 production systems were brought about during the 2000 land reform programme. The soil samples were collected ...

  16. Carbon Storage in Soil Size Fractions Under Two Cacao Agroforestry Systems in Bahia, Brazil

    Science.gov (United States)

    Gama-Rodrigues, Emanuela F.; Ramachandran Nair, P. K.; Nair, Vimala D.; Gama-Rodrigues, Antonio C.; Baligar, Virupax C.; Machado, Regina C. R.

    2010-02-01

    Shaded perennial agroforestry systems contain relatively high quantities of soil carbon (C) resulting from continuous deposition of plant residues; however, the extent to which the C is sequestered in soil will depend on the extent of physical protection of soil organic C (SOC). The main objective of this study was to characterize SOC storage in relation to soil fraction-size classes in cacao ( Theobroma cacao L.) agroforestry systems (AFSs). Two shaded cacao systems and an adjacent natural forest in reddish-yellow Oxisols in Bahia, Brazil were selected. Soil samples were collected from four depth classes to 1 m depth and separated by wet-sieving into three fraction-size classes (>250 μm, 250-53 μm, and cacao AFSs, the C contained in the macroaggregate fraction might become stabilized in the soil. The study shows the role of cacao AFSs in mitigating greenhouse gas (GHG) emission through accumulation and retention of high amounts of organic C in the soils and suggests the potential benefit of this environmental service to the nearly 6 million cacao farmers worldwide.

  17. [Interrelationships between soil fauna and soil environmental factors in China: research advance].

    Science.gov (United States)

    Wang, Yi; Wei, Wei; Yang, Xing-zhong; Chen, Li-ding; Yang, Lei

    2010-09-01

    Soil fauna has close relations with various environmental factors in soil ecosystem. To explore the interrelationships between soil fauna and soil environmental factors is of vital importance to deep understand the dynamics of soil ecosystem and to assess the functioning of the ecosystem. The environmental factors affecting soil fauna can be classified as soil properties and soil external environment. The former contains soil basic physical and chemical properties, soil moisture, and soil pollution. The latter includes vegetation, land use type, landform, and climate, etc. From these aspects, this paper summarized the published literatures in China on the interrelationships between soil fauna and soil environmental factors. It was considered that several problems were existed in related studies, e.g., fewer researches were made in integrating soil fauna's bio-indicator function, research methods were needed to be improved, and the studies on the multi-environmental factors and their large scale spatial-temporal variability were in deficiency. Corresponding suggestions were proposed, i.e., more work should be done according to the practical needs, advanced experiences from abroad should be referenced, and comprehensive studies on multi-environmental factors and long-term monitoring should be conducted on large scale areas.

  18. Smart Braid Feedback for the Closed-Loop Control of Soft Robotic Systems.

    Science.gov (United States)

    Felt, Wyatt; Chin, Khai Yi; Remy, C David

    2017-09-01

    This article experimentally investigates the potential of using flexible, inductance-based contraction sensors in the closed-loop motion control of soft robots. Accurate motion control remains a highly challenging task for soft robotic systems. Precise models of the actuation dynamics and environmental interactions are often unavailable. This renders open-loop control impossible, while closed-loop control suffers from a lack of suitable feedback. Conventional motion sensors, such as linear or rotary encoders, are difficult to adapt to robots that lack discrete mechanical joints. The rigid nature of these sensors runs contrary to the aspirational benefits of soft systems. As truly soft sensor solutions are still in their infancy, motion control of soft robots has so far relied on laboratory-based sensing systems such as motion capture, electromagnetic (EM) tracking, or Fiber Bragg Gratings. In this article, we used embedded flexible sensors known as Smart Braids to sense the contraction of McKibben muscles through changes in inductance. We evaluated closed-loop control on two systems: a revolute joint and a planar, one degree of freedom continuum manipulator. In the revolute joint, our proposed controller compensated for elasticity in the actuator connections. The Smart Braid feedback allowed motion control with a steady-state root-mean-square (RMS) error of [1.5]°. In the continuum manipulator, Smart Braid feedback enabled tracking of the desired tip angle with a steady-state RMS error of [1.25]°. This work demonstrates that Smart Braid sensors can provide accurate position feedback in closed-loop motion control suitable for field applications of soft robotic systems.

  19. Integrated water-crop-soil-management system for evaluating the quality of irrigation water

    International Nuclear Information System (INIS)

    Pla-Sentis, I.

    1983-01-01

    The authors make use of an independent balance of the salts and ions present in the water available for irrigation, based on the residence times in the soil solution that are allowed by solubility limits and drainage conditions, to develop an efficient system for evaluating the quality of such water which combines the factors: water, crop, soil and management. The system is based on the principle that such quality depends not only on the concentration and composition of the salts dissolved in the water, but also on existing possibilities and limitations in using and managing it in respect of the soil and crops, with allowance for the crop's tolerance of salinity, drainage conditions and hydrological properties of the soils, climate and current or potential practices for the management of the irrigation. If this system is used to quantify approximately the time behaviour of the concentration and composition of the salts in the soil solution, it is possible not only to predict the effects on soil, crops and drainage water, but also to evaluate the various combinations of irrigation water, soil, crops and management and to select the most suitable. It is also useful for fairly accurately diagnosing current problems of salinity and for identifying alternatives and possibilities for reclamation. Examples of its use for these purposes in Venezuela are presented with particular reference to the diagnosis of the present and future development of ''salino-sodic'' and ''sodic'' soils by means of low-salt irrigation water spread over agricultural soils with very poor drainage in a sub-humid or semi-arid tropical climate. The authors also describe the use of radiation techniques for gaining an understanding of the relations between the factors making up the system and for improving the quantitative evaluations required to diagnose problems and to select the best management methods for the available irrigation water. (author)

  20. Practical improvements in soil redox potential (Eh) measurement for characterisation of soil properties. Application for comparison of conventional and conservation agriculture cropping systems

    Energy Technology Data Exchange (ETDEWEB)

    Husson, Olivier, E-mail: Olivier.husson@cirad.fr [CIRAD/PERSYST/UPR 115 AIDA and AfricaRice Centre, 01 BP 2031 Cotonou (Benin); Husson, Benoit, E-mail: bhusson@ideeaquaculture.com [IDEEAQUACULTURE, Parc Euromédecine 2, 39 Rue Jean Giroux, 34080 Montpellier (France); Brunet, Alexandre, E-mail: brunet.alexandre@outlook.com [CIRAD/US 49 Analyse, Avenue Agropolis, TA B-49/01, 34398 Montpellier Cedex (France); Babre, Daniel, E-mail: Daniel.babre@cirad.fr [CIRAD/US 49 Analyse, Avenue Agropolis, TA B-49/01, 34398 Montpellier Cedex (France); Alary, Karine, E-mail: Karine.alary@cirad.fr [CIRAD/US 49 Analyse, Avenue Agropolis, TA B-49/01, 34398 Montpellier Cedex (France); Sarthou, Jean-Pierre, E-mail: sarthou@ensat.fr [ENSAT/INRA/INP UMR AGIR. BP 52627, Chemin de Borde Rouge, 31326 Castanet-Tolosan Cedex (France); Charpentier, Hubert, E-mail: Charpentier.hub@wanadoo.fr [La Boisfarderie, Brives 36100 (France); Durand, Michel, E-mail: earldeslacs@orange.fr [Le Cazals, Castanet 81 150 (France); Benada, Jaroslav, E-mail: benada@vukrom.cz [Agrotest fyto, Kromeriz Institute, Havlíckova 2787, 76701 Kromeriz (Czech Republic); Henry, Marc, E-mail: henry@unistra.fr [UMR CNRS/UdS 7140, Université de Strasbourg, Institut Le Bel, 4, rue Blaise Pascal, CS 90032, Strasbourg 67081 (France)

    2016-02-04

    The soil redox potential (Eh) can provide essential information to characterise soil conditions. In practice, however, numerous problems may arise regarding: (i) Eh determination in soils, especially aerobic soils, e.g. variations in the instrumentation and methodology for Eh measurement, high spatial and temporal Eh variability in soils, irreversibility of the redox reaction at the surface electrode, chemical disequilibrium; and (ii) measurement interpretation. This study aimed at developing a standardised method for redox potential measurement in soils, in order to use Eh as a soil quality indicator. This paper presents practical improvements in soil Eh measurement, especially regarding the control of electromagnetic perturbations, electrode choice and preparation, soil sample preparation (drying procedure) and soil:water extraction rate. The repeatability and reproducibility of the measurement method developed are highlighted. The use of Eh corrected at pH7, pe+pH or rH{sub 2}, which are equivalent notions, is proposed to facilitate interpretation of the results. The application of this Eh measurement method allows characterisation of soil conditions with sufficient repeatability, reproducibility and accuracy to demonstrate that conservation agriculture systems positively alter the protonic and electronic balance of soil as compared to conventional systems. - Highlights: • Electromagnetic fields can dramatically perturb soil Eh measurement. • Our method overcomes the main difficulties in soil Eh measurement. • Accurate and reproducible measurement of mean soil Eh are achieved. • Eh{sub pH7}, pe+pH and rH{sub 2} are equivalent notions characterising electron activity. • Agricultural practices alter soil protonic and electronic characteristics.

  1. Animal protein production modules in biological life support systems: Novel combined aquaculture techniques based on the closed equilibrated biological aquatic system (C.E.B.A.S.)

    Science.gov (United States)

    Blüm, V.; Andriske, M.; Kreuzberg, K.; Schreibman, M. P.

    Based on the experiences made with the Closed Equilibrated Biological Aquatic System (C.E.B.A.S.) which was primarily deveoloped for long-term and multi-generation experiments with aquatic animals and plants in a space station highly effective fresh water recycling modules were elaborated utilizing a combination of ammonia oxidizing bacteria filters and higher plants. These exhibit a high effectivity to eliminate phosphate and anorganic nitrogen compounds and arc. in addidition. able to contribute to the oxygen supply of the aquatic animals. The C.E.B.A.S. filter system is able to keep a closed artificial aquatic ecosystem containing teleost fishes and water snails biologically stable for several month and to eliminate waste products deriving from degraded dead fishes without a decrease of the oxygen concentration down to less than 3.5 mg/l at 25 °C. More advanced C.E.B.A.S. filter systems, the BIOCURE filters, were also developed for utilization in semiintensive and intensive aquaculture systems for fishes. In fact such combined animal-plant aquaculture systems represent highly effective productions sites for human food if proper plant and fish species are selected The present papers elucidates ways to novel aquaculture systems in which herbivorous fishes are raised by feeding them with plant biomass produced in the BIOCURE filters and presents the scheme of a modification which utilizes a plant species suitable also for human nutrition. Special attention is paid to the benefits of closed aquaculture system modules which may be integrated into bioregenerative life support systems of a higher complexity for, e. g.. lunar or planetary bases including some psychologiccal aspects of the introduction of animal protein production into plant-based life support systems. Moreover, the basic reproductive biological problems of aquatic animal breeding under reduced gravity are explained leading to a disposition of essential research programs in this context.

  2. Multitube coaxial closed cycle gas laser system

    International Nuclear Information System (INIS)

    Davis, J.W.; Walch, A.P.

    1975-01-01

    A gas laser design capable of long term reliable operation in a commercial environment is disclosed. Various construction details which insulate the laser optics from mechanical distortions and vibrations inevitably present in the environment are developed. Also, a versatile optical cavity made up of modular units which render the basic laser configuration adaptable to alternate designs with different output capabilities is shown in detail. The system built around a convection laser operated in a closed cycle and the working medium is a gas which is excited by direct current electric discharges. (auth)

  3. Soil Tillage Conservation and its Effect on Soil Properties Bioremediation and Sustained Production of Crops

    Science.gov (United States)

    Rusu, Teodor; Ioana Moraru, Paula; Muresan, Liliana; Andriuca, Valentina; Cojocaru, Olesea

    2017-04-01

    Soil Tillage Conservation (STC) is considered major components of agricultural technology for soil conservation strategies and part of Sustainable Agriculture (SA). Human action upon soil by tillage determines important morphological, physical-chemical and biological changes, with different intensities and evaluative directions. Nowadays, internationally is unanimous accepted the fact that global climatic changes are the results of human intervention in the bio-geo-chemical water and material cycle, and the sequestration of carbon in soil is considered an important intervention to limit these changes. STC involves reducing the number of tillage's (minimum tillage) to direct sowing (no-tillage) and plant debris remains at the soil surface in the ratio of at least 30%. Plant debris left on the soil surface or superficial incorporated contributes to increased biological activity and is an important source of carbon sequestration. STC restore soil structure and improve overall soil drainage, allowing more rapid infiltration of water into soil. The result is a soil bioremediation, more productive, better protected against wind and water erosion and requires less fuel for preparing the germinative bed. Carbon sequestration in soil is net advantageous, improving the productivity and sustainability. We present the influence of conventional plough tillage system on soil, water and organic matter conservation in comparison with an alternative minimum tillage (paraplow, chisel plow and rotary harrow) and no-tillage system. The application of STC increased the organic matter content 0.8 to 22.1% and water stabile aggregate content from 1.3 to 13.6%, in the 0-30 cm depth, as compared to the conventional system. For the organic matter content and the wet aggregate stability, the statistical analysis of the data showed, increasing positive significance of STC. While the soil fertility and the wet aggregate stability were initially low, the effect of conservation practices on the

  4. Soil Aggregation, Organic Carbon Concentration, and Soil Bulk Density As Affected by Cover Crop Species in a No-Tillage System

    Directory of Open Access Journals (Sweden)

    Adriano Stephan Nascente

    2015-06-01

    Full Text Available Soil aggregation and the distribution of total organic carbon (TOC may be affected by soil tillage and cover crops. The objective of this study was to determine the effects of crop rotation with cover crops on soil aggregation, TOC concentration in the soil aggregate fractions, and soil bulk density under a no-tillage system (NTS and conventional tillage system (CTS, one plowing and two disking. This was a three-year study with cover crop/rice/cover crop/rice rotations in the Brazilian Cerrado. A randomized block experimental design with six treatments and three replications was used. The cover crops (treatments were: fallow, Panicum maximum, Brachiaria ruziziensis, Brachiaria brizantha, and millet (Pennisetum glaucum. An additional treatment, fallow plus CTS, was included as a control. Soil samples were collected at the depths of 0.00-0.05 m, 0.05-0.10 m, and 0.10-0.20 m after the second rice harvest. The treatments under the NTS led to greater stability in the soil aggregates (ranging from 86.33 to 95.37 % than fallow plus CTS (ranging from 74.62 to 85.94 %. Fallow plus CTS showed the highest number of aggregates smaller than 2 mm. The cover crops affected soil bulk density differently, and the millet treatment in the NTS had the lowest values. The cover crops without incorporation provided the greatest accumulation of TOC in the soil surface layers. The TOC concentration was positively correlated with the aggregate stability index in all layers and negatively correlated with bulk density in the 0.00-0.10 m layer.

  5. An indigenous soil classification system for Bellona Island - a raised atoll in the Solomon Islands

    DEFF Research Database (Denmark)

    Elberling, Bo; Breuning-Madsen, Henrik; Bruun, Thilde Bech

    2010-01-01

    One of the challenges of evaluating existing traditional farming systems is to combine local knowledge and modern scientific methods and terminology. This requires an evaluation of indigenous soil classification in modern terms. This paper focuses on an indigenous soil classification system...... perceive the same four out of seven soil types as highly useful for cultivation and rank these soil types similarly according to their suitability for different crops such as yam, watermelon, cassava and sweet potato. It is concluded that the indigenous soil classification is in line with the soil...... production potential and useful for land evaluation on Bellona....

  6. Development of soil taxation and soil classification as furthered by the Austrian Soil Science Society

    Science.gov (United States)

    Baumgarten, Andreas

    2013-04-01

    Soil taxation and soil classification are important drivers of soil science in Austria. However, the tasks are quite different: whereas soil taxation aims at the evaluation of the productivity potential of the soil, soil classification focusses on the natural development and - especially nowadays - on functionality of the soil. Since the foundation of the Austrian Soil Science Society (ASSS), representatives both directions of the description of the soil have been involved in the common actions of the society. In the first years it was a main target to improve and standardize field descriptions of the soil. Although both systems differ in the general layout, the experts should comply with identical approaches. According to this work, a lot of effort has been put into the standardization of the soil classification system, thus ensuring a common basis. The development, state of the art and further development of both classification and taxation systems initiated and carried out by the ASSS will be shown.

  7. Development of a combined soil-wash/in-furnace vitrification system for soil remediation at DOE sites

    International Nuclear Information System (INIS)

    Pegg, I.L.; Guo, Y.; Lahoda, E.J.; Lai, Shan-Tao; Muller, I.S.; Ruller, J.; Grant, D.C.

    1993-01-01

    This report addresses research and development of technologies for treatment of radioactive and hazardous waste streams at DOE sites. Weldon Spring raffinate sludges were used in a direct vitrification study to investigate their use as fluxing agents in glass formulations when blended with site soil. Storm sewer sediments from the Oak Ridge, TN, Y-12 facility were used for soil washing followed by vitrification of the concentrates. Both waste streams were extensively characterized. Testing showed that both mercury and uranium could be removed from the Y-12 soil by chemical extraction resulting in an 80% volume reduction. Thermal desorption was used on the contaminant-enriched minority fraction to separate the mercury from the uranium. Vitrification tests demonstrated that high waste loading glasses could be produced from the radioactive stream and from the Weldon Spring wastes which showed very good leach resistance, and viscosities and electrical conductivities in the range suitable for joule-heated ceramic melter (JHCM) processing. The conceptual process described combines soil washing, thermal desorption, and vitrification to produce clean soil (about 90% of the input waste stream), non-radioactive mercury, and a glass wasteform; the estimated processing costs for that system are about $260--$400/yd 3 . Results from continuous melter tests performed using Duratek's advanced JHCM (Duramelter) system are also presented. Since life cycle cost estimates are driven largely by volume reduction considerations, the large volume reductions possible with these multi-technology, blended waste stream approaches can produce a more leach resistant wasteform at a lower overall cost than alternative technologies such as cementation

  8. The fate of arsenic in soil-plant systems.

    Science.gov (United States)

    Moreno-Jiménez, Eduardo; Esteban, Elvira; Peñalosa, Jesús M

    2012-01-01

    excluders), and some plants are useful for soil reclamation and in sustainable agriculture, The status of current scientific knowledge allows us to manage As contamination in the soil-plant system and to mitigate arsenic's effects. Phytoremediation is an emerging technology suitable for reclaiming As-contaminated soils and waters. Phytoextraction has been used to clean As-contaminated soils, although its applicability has not yet reached maturity. Phytostabilization has been employed to reduce environmental risk by confining As as an inert form in soils and has shown success in both laboratory experiments and in field trials. Phytofiltration has been used to treat As-enriched waters. Such treatment removes As when it is accumulated in plants grown in or on water. In agricultural food production, appropriate soil management and plant variety/species selection can minimize As-associated human dis- eases and the transfer of As within the food chain. Selecting suitable plants for use on As-contaminated soils may also enhance alternative land use, such as for energy or raw material production.

  9. Analysis the configuration of earthing system based on high-low and low-high soil structure

    International Nuclear Information System (INIS)

    Ramani, A. N.; Ahmad, Abdul Rahman; Sulaima, M. F.; Nasir, M. N. M.; Ahmad, Arfah

    2015-01-01

    Each TNB transmission tower requires a tower footing resistance (TFR) with a lower grounding resistance value that depends on the transmission line voltage. For 132kV and 275kV tower, the TFR must less than 10Ω and 500kV tower must less than 5Ω. The TFR is changeable with variable factors such as soil resistivity. Low TFR provides essential protection to the fault such as lightning strike that may occur at any time. The fault current flow to the lowest resistance path and easily disperses to earth. Back flashover voltage across the insulator of transmission lines may occur when the TFR is high. The TFR is influenced by soil resistivity. There are three parameters affecting the soil resistivity; moisture content, salt content and temperature of the soil. High moisture content in soil will reduce the soil resistivity and resultant low TFR. Small scale moisture control by using Micro Reservoir (MR) irrigation with semi-permeable membranes have the power to offer the stable moisture in soil. By using osmosis concept, it is the process of net movement of water molecules from high potential water to lower potential water though a semi permeable membrane. The MR can withstand for 3 to 5 days without continuous water supply. The MR installed in the centre of the tower that contains a multiple parallel of electrode rods. The concentrated of electrode rods grounding configuration with a combination of MR will improve the TFR even at multilayer soil. As a result, MR gives a little improvement to TFR. The MR in area of concentrated electrode rod configuration to ensure the soil always wet and moist at all times. The changes in soil affect the tower-footing-resistance. The tower-footing-resistance measurement at afternoon is higher than at evening because of the temperature and moisture content in soil is change due to sun radiation

  10. Analysis the configuration of earthing system based on high-low and low-high soil structure

    Energy Technology Data Exchange (ETDEWEB)

    Ramani, A. N.; Ahmad, Abdul Rahman; Sulaima, M. F.; Nasir, M. N. M.; Ahmad, Arfah [Faculty of Electrical Engineering, Universiti Teknikal Malaysia Melaka (UTeM), Hang Tuah Jaya, 76100 Durian Tunggal, Melaka (Malaysia)

    2015-05-15

    Each TNB transmission tower requires a tower footing resistance (TFR) with a lower grounding resistance value that depends on the transmission line voltage. For 132kV and 275kV tower, the TFR must less than 10Ω and 500kV tower must less than 5Ω. The TFR is changeable with variable factors such as soil resistivity. Low TFR provides essential protection to the fault such as lightning strike that may occur at any time. The fault current flow to the lowest resistance path and easily disperses to earth. Back flashover voltage across the insulator of transmission lines may occur when the TFR is high. The TFR is influenced by soil resistivity. There are three parameters affecting the soil resistivity; moisture content, salt content and temperature of the soil. High moisture content in soil will reduce the soil resistivity and resultant low TFR. Small scale moisture control by using Micro Reservoir (MR) irrigation with semi-permeable membranes have the power to offer the stable moisture in soil. By using osmosis concept, it is the process of net movement of water molecules from high potential water to lower potential water though a semi permeable membrane. The MR can withstand for 3 to 5 days without continuous water supply. The MR installed in the centre of the tower that contains a multiple parallel of electrode rods. The concentrated of electrode rods grounding configuration with a combination of MR will improve the TFR even at multilayer soil. As a result, MR gives a little improvement to TFR. The MR in area of concentrated electrode rod configuration to ensure the soil always wet and moist at all times. The changes in soil affect the tower-footing-resistance. The tower-footing-resistance measurement at afternoon is higher than at evening because of the temperature and moisture content in soil is change due to sun radiation.

  11. Soil Response to Global Change: Soil Process Domains and Pedogenic Thresholds (Invited)

    Science.gov (United States)

    Chadwick, O.; Kramer, M. G.; Chorover, J.

    2013-12-01

    The capacity of soil to withstand perturbations, whether driven by climate, land use change, or spread of invasive species, depends on its chemical composition and physical state. The dynamic interplay between stable, well buffered soil process domains and thresholds in soil state and function is a strong determinant of soil response to forcing from global change. In terrestrial ecosystems, edaphic responses are often mediated by availability of water and its flux into and through soils. Water influences soil processes in several ways: it supports biological production, hence proton-donor, electron-donor and complexing-ligand production; it determines the advective removal of dissolution products, and it can promote anoxia that leads microorganisms to utilize alternative electron acceptors. As a consequence climate patterns strongly influence global distribution of soil, although within region variability is governed by other factors such as landscape age, parent material and human land use. By contrast, soil properties can vary greatly among climate regions, variation which is guided by the functioning of a suite of chemical processes that tend to maintain chemical status quo. This soil 'buffering' involves acid-base reactions as minerals weather and oxidation-reduction reactions that are driven by microbial respiration. At the planetary scale, soil pH provides a reasonable indicator of process domains and varies from about 3.5 to10, globally, although most soils lie between about 4.5 and 8.5. Those that are above 7.5 are strongly buffered by the carbonate system, those that are characterized by neutral pH (7.5-6) are buffered by release of non-hydrolyzing cations from primary minerals and colloid surfaces, and those that are buffered by hydrolytic aluminum on colloidal surfaces. Alkali and alkaline (with the exception of limestone parent material) soils are usually associated with arid and semiarid conditions, neutral pH soils with young soils in both dry and wet

  12. Tillage system affects microbiological properties of soil

    Science.gov (United States)

    Delgado, A.; de Santiago, A.; Avilés, M.; Perea, F.

    2012-04-01

    Shannon (H') and Gini (1-G) diversity index of microbial communities were determined in soil samples (0-10 cm depth) taken in autumn 2009. All the enzymatic activities and the biomass estimated by viable cell counting were significantly higher under no-till than under conventional tillage. However, only fluorescents pseudomonas population was increased under no-till, meanwhile oligotrophic bacteria and actinomycetes populations were higher with conventional tillage than with no-till. Overall, there was a higher use all the group of carbon sources used in the BiologR test with conventional tillage than with no-till, by except amines and phenols which showed non-significant differences. This reveals different physiological profiles in the microbial communities under both tillage systems. The Gini diversity was significantly lower with no-till than with conventional tillage. It can be concluded that no-till increases microbial biomass in soil and subsequently enzymatic activities likely ascribed to an increased organic matter content. Under low availability of hydrocarbon sources in soil due to conventional tillage, which promotes a decrease in the organic matter content of the soil, populations of oligotrophods and the diversity of microbial communities are increased. Under these conditions, there must not be dominant carbon sources promoting the selection of microorganisms with a given physiological profile. The reduced hydrocarbon availability and the higher diversity contribute to explain the increased use of carbon sources used in Biolog with conventional tillage than with no-till.

  13. Study of radioactive sr and Cs in soil and soil /plant system at Inshas region

    International Nuclear Information System (INIS)

    Eissa, H.S.M.

    2008-01-01

    The radioactive fallout is considered one of the most major environmental problems that threats public health. The work presented in this thesis is carried out to investigate the level of radioactivity in different environmental samples of soils and vegetations collected from different locations around the NRC at Inshas area and the area nearby (about 30 km radius). Six different locations: Inshas, Shebeen, Abu-Zaabal, Al-Oboor in addition to two sites in the nuclear research center (old reactor and protection department sites) were chosen for the collection of the soil and plant samples. Most typical egyptian soils (sandy, sandyloam, clayey)from three different places (Al-Oboor, Abu-Zaabal, and Shebeen El-Kanatter) were selected for the experiments carried out under laboratory conditions. The plants investigated were grass, old trees and wheat. Cs 137 and Sr 90 were chosen to represent the most important long-lived radionuclides considering the human health, since these nuclides can enter human body via food chain and increase the radiation burden for many years. The following points are considered in this work: 1- Natural radionuclides concentration in different environmental samples of soil and plant especially (grasses and leaves of old trees) were determined using high resolution gamma-spectroscopic system (hyper-pure germanium detector). 2-Two groups of elements have been determined directly in two plant samples from each location (one grass, and the other old trees) together with their corresponding soils.3- Transfer factors (often used to describe the uptake of the radioisotope from soil to plant)of the log-lived radionuclides 137 Cs and 90 from soil to the wheat plant have been studied by radiotracer experiments .4- The sorption behavior of Cs and Sr radionuclides by the different soil types was investigated kinetically using batch techniques.

  14. Comparison between low-cost marker-less and high-end marker-based motion capture systems for the computer-aided assessment of working ergonomics.

    Science.gov (United States)

    Patrizi, Alfredo; Pennestrì, Ettore; Valentini, Pier Paolo

    2016-01-01

    The paper deals with the comparison between a high-end marker-based acquisition system and a low-cost marker-less methodology for the assessment of the human posture during working tasks. The low-cost methodology is based on the use of a single Microsoft Kinect V1 device. The high-end acquisition system is the BTS SMART that requires the use of reflective markers to be placed on the subject's body. Three practical working activities involving object lifting and displacement have been investigated. The operational risk has been evaluated according to the lifting equation proposed by the American National Institute for Occupational Safety and Health. The results of the study show that the risk multipliers computed from the two acquisition methodologies are very close for all the analysed activities. In agreement to this outcome, the marker-less methodology based on the Microsoft Kinect V1 device seems very promising to promote the dissemination of computer-aided assessment of ergonomics while maintaining good accuracy and affordable costs. PRACTITIONER’S SUMMARY: The study is motivated by the increasing interest for on-site working ergonomics assessment. We compared a low-cost marker-less methodology with a high-end marker-based system. We tested them on three different working tasks, assessing the working risk of lifting loads. The two methodologies showed comparable precision in all the investigations.

  15. National innovation system in less successful developing countries

    DEFF Research Database (Denmark)

    Intarakumnerd, Patarapong; Chairatana, Pun-arj; Tangchitpiboon, Tipawan

    2002-01-01

    This paper, using Thailand as a case study, aims at understanding the national innovation system (NIS) in developing countries which are less successful in technological catching-up. In contrast to developed countries, the development level of Thailand’s NIS does not link to its economic structural...... development level. As Thailand moves from agricultural to an increasingly industrial economy, its NIS remains weak and fragmented. The mismatch between the two affected Thailand’s competitiveness and partially contributed to the recent economic crisis. Studies of NIS in countries like Thailand should focus...

  16. [Soil Microbial Respiration Under Different Soil Temperature Conditions and Its Relationship to Soil Dissolved Organic Carbon and Invertase].

    Science.gov (United States)

    Wu, Jing; Chen, Shu-tao; Hu, Zheng-hua; Zhang, Xu

    2015-04-01

    In order to investigate the soil microbial respiration under different temperature conditions and its relationship to soil dissolved organic carbon ( DOC) and invertase, an indoor incubation experiment was performed. The soil samples used for the experiment were taken from Laoshan, Zijinshan, and Baohuashan. The responses of soil microbial respiration to the increasing temperature were studied. The soil DOC content and invertase activity were also measured at the end of incubation. Results showed that relationships between cumulative microbial respiration of different soils and soil temperature could be explained by exponential functions, which had P values lower than 0.001. The coefficient of temperature sensitivity (Q10 value) varied from 1.762 to 1.895. The Q10 value of cumulative microbial respiration decreased with the increase of soil temperature for all soils. The Q10 value of microbial respiration on 27 days after incubation was close to that of 1 day after incubation, indicating that the temperature sensitivity of recalcitrant organic carbon may be similar to that of labile organic carbon. For all soils, a highly significant ( P = 0.003 ) linear relationship between cumulative soil microbial respiration and soil DOC content could be observed. Soil DOC content could explain 31.6% variances of cumulative soil microbial respiration. For the individual soil and all soils, the relationship between cumulative soil microbial respiration and invertase activity could be explained by a highly significant (P soil microbial respiration.

  17. Correlation of the Rock Mass Rating (RMR) System with the Unified Soil Classification System (USCS): Introduction of the Weak Rock Mass Rating System (W-RMR)

    Science.gov (United States)

    Warren, Sean N.; Kallu, Raj R.; Barnard, Chase K.

    2016-11-01

    Underground gold mines in Nevada are exploiting increasingly deeper ore bodies comprised of weak to very weak rock masses. The Rock Mass Rating (RMR) classification system is widely used at underground gold mines in Nevada and is applicable in fair to good-quality rock masses, but is difficult to apply and loses reliability in very weak rock mass to soil-like material. Because very weak rock masses are transition materials that border engineering rock mass and soil classification systems, soil classification may sometimes be easier and more appropriate to provide insight into material behavior and properties. The Unified Soil Classification System (USCS) is the most likely choice for the classification of very weak rock mass to soil-like material because of its accepted use in tunnel engineering projects and its ability to predict soil-like material behavior underground. A correlation between the RMR and USCS systems was developed by comparing underground geotechnical RMR mapping to laboratory testing of bulk samples from the same locations, thereby assigning a numeric RMR value to the USCS classification that can be used in spreadsheet calculations and geostatistical analyses. The geotechnical classification system presented in this paper including a USCS-RMR correlation, RMR rating equations, and the Geo-Pick Strike Index is collectively introduced as the Weak Rock Mass Rating System (W-RMR). It is the authors' hope that this system will aid in the classification of weak rock masses and more usable design tools based on the RMR system. More broadly, the RMR-USCS correlation and the W-RMR system help define the transition between engineering soil and rock mass classification systems and may provide insight for geotechnical design in very weak rock masses.

  18. [Effects of simulated acid rain on respiration rate of cropland system with different soil pH].

    Science.gov (United States)

    Zhu, Xue-zhu; Zhang, Gao-chuan; Li, Hui

    2009-10-15

    To evaluate the effects of acid rain on the respiration rate of cropland system, an outdoor pot experiment was conducted with paddy soils of pH 5.48 (S1), pH 6.70 (S1) and pH 8.18 (S3) during the 2005-2007 wheat-growing seasons. The cropland system was exposed to acid rain by spraying the wheat foliage and irrigating the soil with simulated rainwater of T1 (pH 6.0), T2 (pH 6.0, ionic concentration was twice as rainwater T1), and T3 (pH 4.4, ionic concentration was twice as rainwater T1), respectively. The static opaque chamber-gas chromatograph method was used to measure CO2 fluxes from cropland system. The results showed that acid rain affected the respiration rate of cropland system through crop plant, and the cropland system could adapt to acid rain. Acid rainwater significantly increased the average respiration rate in alkaline soil (S3) cropland system, while it had no significant effects on the average respiration rate in neutral soil (S2) and acidic soil (S1) cropland systems. During 2005-2006, after the alkaline soil cropland system was treated with rainwater T3, the average respiration rate was 23.6% and 27.6% higher than that of alkaline soil cropland system treated with rainwater T1 and T2, respectively. During March to April, the respiration rate was enhanced with the increase of rainwater ionic concentration, while it was dropped with the decrease of rainwater pH value in acidic soil cropland system. It was demonstrated that soil pH and crop plant played important roles on the respiration rate of cropland system.

  19. Closed Cycle Solar Refrigeration with the Calcium Chloride System ...

    African Journals Online (AJOL)

    A closed cycle solid absorption intermittent refrigerator, using CaC12 absorbent and NH3 refrigerant, was constructed and tested to obtain the instantaneous and cumulative available overall COP. The combined collector/absorber/generator unit had double glazing of 1.14 m2 exposed areas. The system was fitted with a ...

  20. Experimental Study on Fatigue Performance of Foamed Lightweight Soil

    Science.gov (United States)

    Qiu, Youqiang; Yang, Ping; Li, Yongliang; Zhang, Liujun

    2017-12-01

    In order to study fatigue performance of foamed lightweight soil and forecast its fatigue life in the supporting project, on the base of preliminary tests, beam fatigue tests on foamed lightweight soil is conducted by using UTM-100 test system. Based on Weibull distribution and lognormal distribution, using the mathematical statistics method, fatigue equations of foamed lightweight soil are obtained. At the same time, according to the traffic load on real road surface of the supporting project, fatigue life of formed lightweight soil is analyzed and compared with the cumulative equivalent axle loads during the design period of the pavement. The results show that even the fatigue life of foamed lightweight soil has discrete property, the linear relationship between logarithmic fatigue life and stress ratio still performs well. Especially, the fatigue life of Weibull distribution is more close to that derived from the lognormal distribution, in the instance of 50% guarantee ratio. In addition, the results demonstrated that foamed lightweight soil as subgrade filler has good anti-fatigue performance, which can be further adopted by other projects in the similar research domain.

  1. Microbiological and faunal soil attributes of coffee cultivation under different management systems in Brazil

    Directory of Open Access Journals (Sweden)

    D. R. Lammel

    Full Text Available Abstract Brazil is the biggest coffee producer in the world and different plantation management systems have been applied to improve sustainability and soil quality. Little is known about the environmental effects of these different management systems, therefore, the goal of this study was to use soil biological parameters as indicators of changes. Soils from plantations in Southeastern Brazil with conventional (CC, organic (OC and integrated management systems containing intercropping of Brachiaria decumbens (IB or Arachis pintoi (IA were sampled. Total organic carbon (TOC, microbial biomass carbon (MBC and nitrogen (MBN, microbial activity (C-CO2, metabolic quotient (qCO2, the enzymes dehydrogenase, urease, acid phosphatase and arylsulphatase, arbuscular mycorrhizal fungi (AMF colonization and number of spores and soil fauna were evaluated. The greatest difference between the management systems was seen in soil organic matter content. The largest quantity of TOC was found in the OC, and the smallest was found in IA. TOC content influenced soil biological parameters. The use of all combined attributes was necessary to distinguish the four systems. Each management presented distinct faunal structure, and the data obtained with the trap method was more reliable than the TSBF (Tropical Soils method. A canonic correlation analysis showed that Isopoda was correlated with TOC and the most abundant order with OC. Isoptera was the most abundant faunal order in IA and correlated with MBC. Overall, OC had higher values for most of the biological measurements and higher populations of Oligochaeta and Isopoda, corroborating with the concept that the OC is a more sustainable system.

  2. Microbiological and faunal soil attributes of coffee cultivation under different management systems in Brazil.

    Science.gov (United States)

    Lammel, D R; Azevedo, L C B; Paula, A M; Armas, R D; Baretta, D; Cardoso, E J B N

    2015-11-01

    Brazil is the biggest coffee producer in the world and different plantation management systems have been applied to improve sustainability and soil quality. Little is known about the environmental effects of these different management systems, therefore, the goal of this study was to use soil biological parameters as indicators of changes. Soils from plantations in Southeastern Brazil with conventional (CC), organic (OC) and integrated management systems containing intercropping of Brachiaria decumbens (IB) or Arachis pintoi (IA) were sampled. Total organic carbon (TOC), microbial biomass carbon (MBC) and nitrogen (MBN), microbial activity (C-CO2), metabolic quotient (qCO2), the enzymes dehydrogenase, urease, acid phosphatase and arylsulphatase, arbuscular mycorrhizal fungi (AMF) colonization and number of spores and soil fauna were evaluated. The greatest difference between the management systems was seen in soil organic matter content. The largest quantity of TOC was found in the OC, and the smallest was found in IA. TOC content influenced soil biological parameters. The use of all combined attributes was necessary to distinguish the four systems. Each management presented distinct faunal structure, and the data obtained with the trap method was more reliable than the TSBF (Tropical Soils) method. A canonic correlation analysis showed that Isopoda was correlated with TOC and the most abundant order with OC. Isoptera was the most abundant faunal order in IA and correlated with MBC. Overall, OC had higher values for most of the biological measurements and higher populations of Oligochaeta and Isopoda, corroborating with the concept that the OC is a more sustainable system.

  3. Effect of adding phosphogypsum to the soil on the growth, yields, radionuclides, trace elements and fluorine accumulation in some crops

    International Nuclear Information System (INIS)

    Al-Oudat, M.; Sharabi, N. E.; Kanacri, S.

    2001-12-01

    large quantities of phosphogypsum, a by-product of phosphate fertilizer industry, are stacked close to urban areas in Syria. This may pose negative impacts on the environment. Many studies have reported positive effects of phosphogypsum application on nutrient levels, physical and chemical properties of agricultural soils. There are some concerns that the application of phosphogypsum to agricultural lands may result in the uptake by plant of radionuclides, fluorine and trace elements. Phosphogypsum, which has a radioactivity of 430 Bq/Kg, was mixed with silty loam soil, at different rates (0, 10, 20, 40 and 80 t/ha), the experiments were carried out using chick pea, maize cotton and spinach. The results showed that adding phosphogypsum to the soil, at a rate ranging between 10 and 40 t/ha, increased the infiltration rate, electrical conductivity and concentration of available S, Mg, Ca, P. It also increased significantly the yields of studied crops. The radioactivities in the shoot systems and grains yields of crops grown on these soil-phosphogypsum mixtures were below detection level. In addition, phosphogypsum application did not cause accumulation of trace elements in soil or plants. The fluorine concentrations in plants increased but remained less than the allowable level (30 ppm). Therefor, adding phosphogypsum to agricultural soils (at a rate of 10-20 t/ha) can be considered an-effective way of improving soil properties, crop productivity and represents a way of phosphogypsum utilization which reduces its negative effects on the environment. (authors)

  4. MDAS2: A Data Acquisition System for the Soil Mechanic Laboratory

    International Nuclear Information System (INIS)

    Alberdi, J.; Barcala, J. M.

    2000-01-01

    The Soil Mechanic Laboratory in CIEMAT is working to characterize a bentonite which may be use in the storage of radioactive waste. The bentonite is studied with several tests, frequently used in soil mechanics. This document describes the data acquisition system used in one of these experiments

  5. SPATIAL CORRELATION BETWEEN PHYSICAL PROPERTIES OF SOIL AND WEEDS IN TWO MANAGEMENT SYSTEMS

    Directory of Open Access Journals (Sweden)

    Valter Roberto Schaffrath

    2015-02-01

    Full Text Available The spatial correlation between soil properties and weeds is relevant in agronomic and environmental terms. The analysis of this correlation is crucial for the interpretation of its meaning, for influencing factors such as dispersal mechanisms, seed production and survival, and the range of influence of soil management techniques. This study aimed to evaluate the spatial correlation between the physical properties of soil and weeds in no-tillage (NT and conventional tillage (CT systems. The following physical properties of soil and weeds were analyzed: soil bulk density, macroporosity, microporosity, total porosity, aeration capacity of soil matrix, soil water content at field capacity, weed shoot biomass, weed density, Commelina benghalensis density, and Bidens pilosa density. Generally, the ranges of the spatial correlations were higher in NT than in CT. The cross-variograms showed that many variables have a structure of combined spatial variation and can therefore be mapped from one another by co-kriging. This combined variation also allows inferences about the physical and biological meanings of the study variables. Results also showed that soil management systems influence the spatial dependence structure significantly.

  6. A closed-loop system for frequency tracking of piezoresistive cantilever sensors

    Science.gov (United States)

    Wasisto, Hutomo Suryo; Zhang, Qing; Merzsch, Stephan; Waag, Andreas; Peiner, Erwin

    2013-05-01

    A closed loop circuit capable of tracking resonant frequencies for MEMS-based piezoresistive cantilever resonators is developed in this work. The proposed closed-loop system is mainly based on a phase locked loop (PLL) circuit. In order to lock onto the resonant frequency of the resonator, an actuation signal generated from a voltage-controlled oscillator (VCO) is locked to the phase of the input reference signal of the cantilever sensor. In addition to the PLL component, an instrumentation amplifier and an active low pass filter (LPF) are connected to the system for gaining the amplitude and reducing the noise of the cantilever output signals. The LPF can transform a rectangular signal into a sinusoidal signal with voltage amplitudes ranging from 5 to 10 V which are sufficient for a piezoactuator input (i.e., maintaining a large output signal of the cantilever sensor). To demonstrate the functionality of the system, a self-sensing silicon cantilever resonator with a built-in piezoresistive Wheatstone bridge is fabricated and integrated with the circuit. A piezoactuator is utilized for actuating the cantilever into resonance. Implementation of this closed loop system is used to track the resonant frequency of a silicon cantilever-based sensor resonating at 9.4 kHz under a cross-sensitivity test of ambient temperature. The changes of the resonant frequency are interpreted using a frequency counter connected to the system. From the experimental results, the temperature sensitivity and coefficient of the employed sensor are 0.3 Hz/°C and 32.8 ppm/°C, respectively. The frequency stability of the system can reach up to 0.08 Hz. The development of this system will enable real-time nanoparticle monitoring systems and provide a miniaturization of the instrumentation modules for cantilever-based nanoparticle detectors.

  7. Biosphere II: engineering of manned, closed ecological systems.

    Science.gov (United States)

    Dempster, W F

    1991-01-01

    Space Biospheres and Ventures, a private, for-profit firm, has undertaken a major research and development project in the study of biospheres, with the objective of creating and producing biospheres. Biosphere II-scheduled for completion in March 1991-will be essentially isolated from the existing biosphere by a closed structure, composed of components derived from the existing biosphere. Like the biosphere of the Earth, Biosphere II will be essentially closed to exchanges of material or living organisms with the surrounding environment and open to energy and information exchanges. Also, like the biosphere of the Earth, Biosphere II will contain five kingdoms of life, a variety of ecosystems, plus humankind, culture, and technics. The system is designed to be complex, stable and evolving throughout its intended 100-year lifespan, rather than static. Biosphere II will cover approximately 1.3 hectare and contain 200,000 m3 in volume, with seven major biomes: tropical rainforest, tropical savannah, marsh, marine, desert, intensive agriculture, and human habitat. An interdisciplinary team of leading scientific, ecological, management, architectural, and engineering consultants have been contracted by Space Biospheres Ventures for the project. Potential applications for biospheric systems include scientific and ecological management research, refuges for endangered species, and life habitats for manned stations on spacecraft or other planets.

  8. Faunal Drivers of Soil Flux Dynamics via Alterations in Crack Structure

    Science.gov (United States)

    DeCarlo, Keita; Caylor, Kelly

    2016-04-01

    Organismal activity, in addition to its role in ecological feedbacks, has the potential to serve as instigators or enhancers of atmospheric and hydrologic processes via alterations in soil structural regimes. We investigated the biomechanical effect of faunal activity on soil carbon dynamics via changes in soil crack structure, focusing on three dryland soil systems: bioturbated, biocompacted and undisturbed soils. Carbon fluxes were characterized using a closed-system respiration chamber, with CO2 concentration differences measured using an infrared gas analyzer (IRGA). Results show that faunal influences play a divergent biomechanics role in bulk soil cracking: bioturbation induced by belowground fauna creates "surficial" (shallow, large, well-connected) networks relative to the "systematic" (deep, moderate, poorly connected) networks created by aboveground fauna. The latter also shows a "memory" of past wetting/drying events in the consolidated soil through a crack layering effect. These morphologies further drive differences in soil carbon flux: under dry conditions, bioturbated and control soils show a persistently high and low mean carbon flux, respectively, while biocompacted soils show a large diurnal trend, with daytime lows and nighttime highs comparable to the control and bioturbated soils, respectively. Overall fluxes under wet conditions are considerably higher, but also more variable, though higher mean fluxes are observed in the biocompacted and bioturbated soils. Our results suggest that the increased surface area in the bioturbated soils create enhanced but constant diffusive processes, whereas the increased thermal gradient in the biocompacted soils create novel convective processes that create high fluxes that are diurnal in nature.

  9. Heavy metal dynamics in the soil-leaf-fruit system under intensive apple cultivation

    Directory of Open Access Journals (Sweden)

    Murtić Senad

    2014-01-01

    Full Text Available One of the major problems confronting agricultural production is heavy metal contamination of agricultural soils, which imposes considerable limitations on productivity and leads to great consumer health and safety concerns about the products obtained on these soils. The objective of this study was to evaluate heavy metal dynamics in the soil-leaf-fruit system in an intensive apple cv. 'Idared' planting located in the Municipality of Goražde. Heavy metal contents in the soil samples and plant material were determined by atomic absorption spectrophotometry using a Shimadzu 7000 AA device, according to the instructions specified in the ISO 11047 method. The dynamics of the heavy metals analyzed, excepting zinc, in the soil-leaf-fruit system was characterized by relatively high total levels of heavy metals in the soil and a very low degree of their accumulation in the leaves and in particular the fruits. No fruit sample was found to have toxic levels of any of the heavy metals analyzed. In terms of soil contamination, this suggests the suitability of the study location for safe apple fruit production.

  10. C and N Content in Density Fractions of Whole Soil and Soil Size Fraction Under Cacao Agroforestry Systems and Natural Forest in Bahia, Brazil

    Science.gov (United States)

    Rita, Joice Cleide O.; Gama-Rodrigues, Emanuela Forestieri; Gama-Rodrigues, Antonio Carlos; Polidoro, Jose Carlos; Machado, Regina Cele R.; Baligar, Virupax C.

    2011-07-01

    Agroforestry systems (AFSs) have an important role in capturing above and below ground soil carbon and play a dominant role in mitigation of atmospheric CO2. Attempts has been made here to identify soil organic matter fractions in the cacao-AFSs that have different susceptibility to microbial decomposition and further represent the basis of understanding soil C dynamics. The objective of this study was to characterize the organic matter density fractions and soil size fractions in soils of two types of cacao agroforestry systems and to compare with an adjacent natural forest in Bahia, Brazil. The land-use systems studied were: (1) a 30-year-old stand of natural forest with cacao (cacao cabruca), (2) a 30-year-old stand of cacao with Erythrina glauca as shade trees (cacao + erythrina), and (3) an adjacent natural forest without cacao. Soil samples were collected from 0-10 cm depth layer in reddish-yellow Oxisols. Soil samples was separated by wet sieving into five fraction-size classes (>2000 μm, 1000-2000 μm, 250-1000 μm, 53-250 μm, and cacao AFS soils consisted mainly (65 %) of mega-aggregates (>2000 μm) mixed with macroaggregates (32-34%), and microaggregates (1-1.3%). Soil organic carbon (SOC) and total N content increased with increasing soil size fraction in all land-use systems. Organic C-to-total N ratio was higher in the macroaggregate than in the microaggregate. In general, in natural forest and cacao cabruca the contribution of C and N in the light and heavy fractions was similar. However, in cacao + erythrina the heavy fraction was the most common and contributed 67% of C and 63% of N. Finding of this study shows that the majority of C and N in all three systems studied are found in macroaggregates, particularly in the 250-1000 μm size aggregate class. The heavy fraction was the most common organic matter fraction in these soils. Thus, in mature cacao AFS on highly weathered soils the main mechanisms of C stabilization could be the physical

  11. Autologous fat grafting: use of closed syringe microcannula system for enhanced autologous structural grafting

    Directory of Open Access Journals (Sweden)

    Alexander RW

    2013-04-01

    Full Text Available Robert W Alexander,1 David Harrell2 1Department of Surgery, School of Medicine and Dentistry, University of Washington, Seattle, WA, USA; 2Harvest-Terumo Inc, Plymouth, MA, USA Objectives: Provide background for use of acquiring autologous adipose tissue as a tissue graft and source of adult progenitor cells for use in cosmetic plastic surgery. Discuss the background and mechanisms of action of closed syringe vacuum lipoaspiration, with emphasis on accessing adipose-derived mesenchymal/stromal cells and the stromal vascular fraction (SVF for use in aesthetic, structural reconstruction and regenerative applications. Explain a proven protocol for acquiring high-quality autologous fat grafts (AFG with use of disposable, microcannula systems. Design: Explain the components and advantage of use of the patented super luer-lock and microcannulas system for use with the closed-syringe system. A sequential explanation of equipment selection for minimally traumatic lipoaspiration in small volumes is presented, including use of blunt injection cannulas to reduce risk of embolism. Results: Thousands of AFG have proven safe and efficacious for lipoaspiration techniques for large and small structural fat grafting procedures. The importance and advantages of gentle harvesting of the adipose tissue complex has become very clear in the past 5 years. The closed-syringe system offers a minimally invasive, gentle system with which to mobilize subdermal fat tissues in a suspension form. Resulting total nuclear counting of undifferentiated cells of the adipose-derived -SVF suggests that the yield achieved is better than use of always-on, constant mechanical pump applied vacuum systems. Conclusion: Use of a closed-syringe lipoaspiration system featuring disposable microcannulas offers a safe and effective means of harvesting small volumes of nonmanipulated adipose tissues and its accompanying progenitor cells within the SVF. Closed syringes and microcannulas are

  12. Soil-structure interaction including nonlinear soil

    OpenAIRE

    Gicev, Vlado

    2008-01-01

    There are two types of models of soil-structure system depending upon the rigidity of foundation: models with rigid and models with flexible foundation. Main features of the soil-structure interaction phenomenon: -wave scattering, -radiation damping, -reduction of the system frequencies. In this presentation, the influence of interaction on the development of nonlinear zones in the soil is studied.

  13. A Compact Closed-Loop Optogenetics System Based on Artifact-Free Transparent Graphene Electrodes

    Directory of Open Access Journals (Sweden)

    Xin Liu

    2018-03-01

    Full Text Available Electrophysiology is a decades-old technique widely used for monitoring activity of individual neurons and local field potentials. Optogenetics has revolutionized neuroscience studies by offering selective and fast control of targeted neurons and neuron populations. The combination of these two techniques is crucial for causal investigation of neural circuits and understanding their functional connectivity. However, electrical artifacts generated by light stimulation interfere with neural recordings and hinder the development of compact closed-loop systems for precise control of neural activity. Here, we demonstrate that transparent graphene micro-electrodes fabricated on a clear polyethylene terephthalate film eliminate the light-induced artifact problem and allow development of a compact battery-powered closed-loop optogenetics system. We extensively investigate light-induced artifacts for graphene electrodes in comparison to metal control electrodes. We then design optical stimulation module using micro-LED chips coupled to optical fibers to deliver light to intended depth for optogenetic stimulation. For artifact-free integration of graphene micro-electrode recordings with optogenetic stimulation, we design and develop a compact closed-loop system and validate it for different frequencies of interest for neural recordings. This compact closed-loop optogenetics system can be used for various applications involving optogenetic stimulation and electrophysiological recordings.

  14. NUTRIENT BALANCE IN WATER HARVESTING SOILS

    Directory of Open Access Journals (Sweden)

    Díaz, F

    2005-05-01

    Full Text Available Dryland farming on Fuerteventura and Lanzarote (Canary Islands, Spain, which has an annual rainfall of less than 150 mm/year, has been based traditionally on water harvesting techniques (known locally as “gavias”. Periods of high productivity alternate with those of very low yield. The systems are sustainable in that they reduce erosive processes, contribute to soil and soil-water conservation and are largely responsible for maintaining the soil’s farming potential. In this paper we present the chemical fertility status and nutrient balance of soils in five “gavia” systems. The results are compared with those obtained in adjacent soils where this water harvesting technique is not used. The main crops are wheat, barley, maize, lentils and chick-peas. Since neither organic nor inorganic fertilisers are used, nutrients are derived mainly from sediments carried by runoff water. Nutrients are lost mainly through crop harvesting and harvest residues. The soils where water harvesting is used have lower salt and sodium in the exchange complex, are higher in carbon, nitrogen, copper and zinc and have similar phosphorous and potassium content. It is concluded that the systems improve the soil’s natural fertility and also that natural renovation of nutrients occurs thanks to the surface deposits of sediments, which mix with the arable layer. The system helps ensure adequate fertility levels, habitual in arid regions, thus allowing dryland farming to be carried out.

  15. Organic Control of Dioctahedral and Trioctahedral Clay Formation in an Alkaline Soil System in the Pantanal Wetland of Nhecolândia, Brazil.

    Science.gov (United States)

    Barbiero, Laurent; Berger, Gilles; Rezende Filho, Ary T; Meunier, Jean-François; Martins-Silva, Elisângela R; Furian, Sonia

    2016-01-01

    Recent studies have focused on the formation of authigenic clays in an alkaline soil system surrounding lakes of the Nhecolândia region, Pantanal wetland. The presence of trioctahedral Mg-smectites (stevensite and saponite types), which requires low Al and Fe contents in the soil solution for its formation, contrasts with the neoformation of dioctahedral Fe-mica (glauconite, and Fe-illite), which instead requires solutions relatively enriched in Al and Fe. This study aims to understand the conditions of co-existence of both, Mg-smectite and Fe-mica a common clay association in former or modern alkaline soil systems and sediments. The study was carried out along an alkaline soil catena representative of the region. The soil organization revealed that Mg-smectite occur in top soil close to the lake, whereas Fe-mica dominate in the clay fraction of deeper greenish horizons a few meters apart. We propose here that this spatial distribution is controlled by the lateral transfer of Fe and Al with organic ligands. Alkaline organic rich solutions (DOC up to 738 mg L-1) collected in the watertable were centrifuged and filtered through membranes of decreasing pore size (0.45 μm, 0.2 μm, 30 KDa, 10 KDa, 3 KDa) to separate colloidal and dissolved fractions. Fe, Al, Si, Mg and K were analysed for each fraction. Although the filtration had no influence on Si and K contents, almost 90% of Fe (up to 2.3 mg L-1) and Al (up to 7 mg L-1) are retained at the first cutoff threshold of 0.45μm. The treatment of the same solutions by oxygen peroxide before filtration shows that a large proportion of Fe and Al were bonded to organic colloids in alkaline soil solution at the immediate lake border, allowing Mg-smectite precipitation. The fast mineralization of the organic matter a few meters apart from the lake favors the release of Fe and Al necessary for Fe-mica neoformation. In comparison with chemical and mineralogical characteristics of alkaline environments described in the

  16. Organic Control of Dioctahedral and Trioctahedral Clay Formation in an Alkaline Soil System in the Pantanal Wetland of Nhecolândia, Brazil

    Science.gov (United States)

    Meunier, Jean-François; Martins-Silva, Elisângela R.; Furian, Sonia

    2016-01-01

    Recent studies have focused on the formation of authigenic clays in an alkaline soil system surrounding lakes of the Nhecolândia region, Pantanal wetland. The presence of trioctahedral Mg-smectites (stevensite and saponite types), which requires low Al and Fe contents in the soil solution for its formation, contrasts with the neoformation of dioctahedral Fe-mica (glauconite, and Fe-illite), which instead requires solutions relatively enriched in Al and Fe. This study aims to understand the conditions of co-existence of both, Mg-smectite and Fe-mica a common clay association in former or modern alkaline soil systems and sediments. The study was carried out along an alkaline soil catena representative of the region. The soil organization revealed that Mg-smectite occur in top soil close to the lake, whereas Fe-mica dominate in the clay fraction of deeper greenish horizons a few meters apart. We propose here that this spatial distribution is controlled by the lateral transfer of Fe and Al with organic ligands. Alkaline organic rich solutions (DOC up to 738 mg L-1) collected in the watertable were centrifuged and filtered through membranes of decreasing pore size (0.45 μm, 0.2 μm, 30 KDa, 10 KDa, 3 KDa) to separate colloidal and dissolved fractions. Fe, Al, Si, Mg and K were analysed for each fraction. Although the filtration had no influence on Si and K contents, almost 90% of Fe (up to 2.3 mg L-1) and Al (up to 7 mg L-1) are retained at the first cutoff threshold of 0.45μm. The treatment of the same solutions by oxygen peroxide before filtration shows that a large proportion of Fe and Al were bonded to organic colloids in alkaline soil solution at the immediate lake border, allowing Mg-smectite precipitation. The fast mineralization of the organic matter a few meters apart from the lake favors the release of Fe and Al necessary for Fe-mica neoformation. In comparison with chemical and mineralogical characteristics of alkaline environments described in the

  17. Organic Control of Dioctahedral and Trioctahedral Clay Formation in an Alkaline Soil System in the Pantanal Wetland of Nhecolândia, Brazil.

    Directory of Open Access Journals (Sweden)

    Laurent Barbiero

    Full Text Available Recent studies have focused on the formation of authigenic clays in an alkaline soil system surrounding lakes of the Nhecolândia region, Pantanal wetland. The presence of trioctahedral Mg-smectites (stevensite and saponite types, which requires low Al and Fe contents in the soil solution for its formation, contrasts with the neoformation of dioctahedral Fe-mica (glauconite, and Fe-illite, which instead requires solutions relatively enriched in Al and Fe. This study aims to understand the conditions of co-existence of both, Mg-smectite and Fe-mica a common clay association in former or modern alkaline soil systems and sediments. The study was carried out along an alkaline soil catena representative of the region. The soil organization revealed that Mg-smectite occur in top soil close to the lake, whereas Fe-mica dominate in the clay fraction of deeper greenish horizons a few meters apart. We propose here that this spatial distribution is controlled by the lateral transfer of Fe and Al with organic ligands. Alkaline organic rich solutions (DOC up to 738 mg L-1 collected in the watertable were centrifuged and filtered through membranes of decreasing pore size (0.45 μm, 0.2 μm, 30 KDa, 10 KDa, 3 KDa to separate colloidal and dissolved fractions. Fe, Al, Si, Mg and K were analysed for each fraction. Although the filtration had no influence on Si and K contents, almost 90% of Fe (up to 2.3 mg L-1 and Al (up to 7 mg L-1 are retained at the first cutoff threshold of 0.45μm. The treatment of the same solutions by oxygen peroxide before filtration shows that a large proportion of Fe and Al were bonded to organic colloids in alkaline soil solution at the immediate lake border, allowing Mg-smectite precipitation. The fast mineralization of the organic matter a few meters apart from the lake favors the release of Fe and Al necessary for Fe-mica neoformation. In comparison with chemical and mineralogical characteristics of alkaline environments described

  18. Tracing the origin of dissolved silicon transferred from various soil-plant systems towards rivers: a review

    Directory of Open Access Journals (Sweden)

    J.-T. Cornelis

    2011-01-01

    Full Text Available Silicon (Si released as H4SiO4 by weathering of Si-containing solid phases is partly recycled through vegetation before its land-to-rivers transfer. By accumulating in terrestrial plants to a similar extent as some major macronutrients (0.1–10% Si dry weight, Si becomes largely mobile in the soil-plant system. Litter-fall leads to a substantial reactive biogenic silica pool in soil, which contributes to the release of dissolved Si (DSi in soil solution. Understanding the biogeochemical cycle of silicon in surface environments and the DSi export from soils into rivers is crucial given that the marine primary bio-productivity depends on the availability of H4SiO4 for phytoplankton that requires Si. Continental fluxes of DSi seem to be deeply influenced by climate (temperature and runoff as well as soil-vegetation systems. Therefore, continental areas can be characterized by various abilities to transfer DSi from soil-plant systems towards rivers. Here we pay special attention to those processes taking place in soil-plant systems and controlling the Si transfer towards rivers. We aim at identifying relevant geochemical tracers of Si pathways within the soil-plant system to obtain a better understanding of the origin of DSi exported towards rivers. In this review, we compare different soil-plant systems (weathering-unlimited and weathering-limited environments and the variations of the geochemical tracers (Ge/Si ratios and δ30Si in DSi outputs. We recommend the use of biogeochemical tracers in combination with Si mass-balances and detailed physico-chemical characterization of soil-plant systems to allow better insight in the sources and fate of Si in these biogeochemical systems.

  19. Effects of lead contamination on soil microbial activity and rice physiological indices in soil-Pb-rice (Oryza sativa L.) system.

    Science.gov (United States)

    Zeng, Lu-Sheng; Liao, Min; Chen, Cheng-Li; Huang, Chang-Yong

    2006-10-01

    The effect of lead (Pb) treatment on the soil microbial activities (soil microbial biomass and soil basal respiration) and rice physiological indices were studied by greenhouse pot experiment. Pb was applied as lead acetate at six different levels in two different paddy soils, namely 0 (control), 100, 300, 500, 700, 900 mg kg-1 soil. The results showed that the application of Pb at lower level (500 mg Pb kg-1 soil), which might be the critical concentration of Pb causing a significant decline in the soil microbial activities. However, the degree of influence on soil microbial activities by Pb was related to the clay and organic matter contents of the soils. On the other hand, when the level of Pb treatments increased to 500 mg kg-1, there was ecological risk for both soil microbial activities and plants. The results also revealed that there was a consistent trend that the chlorophyll contents increased initially, and then decreased gradually with increase in Pb concentration. Pb was effective in inducing proline accumulation and its toxicity causes oxidative stress in rice plants. In a word, soil microbial activities and rice physiological indices, therefore, may be sensitive indicators reflecting environmental stress in soil-Pb-rice system.

  20. Soil classification and carbon storage in cacao agroforestry farming systems of Bahia, Brazil

    Science.gov (United States)

    Information concerning the classification of soils and their properties under cacao agroforestry systems of the Atlantic rain forest biome region in the Southeast of Bahia Brazil is largely unknown. Soil and climatic conditions in this region are favorable for high soil carbon storage. This study is...

  1. Soil carbon sequestration in rainfed production systems in the semiarid tropics of India.

    Science.gov (United States)

    Srinivasarao, Ch; Lal, Rattan; Kundu, Sumanta; Babu, M B B Prasad; Venkateswarlu, B; Singh, Anil Kumar

    2014-07-15

    Severe soil organic carbon (SOC) depletion is a major constraint in rainfed agroecosystems in India because it directly influences soil quality, crop productivity and sustainability. The magnitude of soil organic, inorganic and total carbon stocks in the semi-arid bioclimate is estimated at 2.9, 1.9 and 4.8 Pg respectively. Sorghum, finger millet, pearl millet, maize, rice, groundnut, soybean, cotton, food legumes etc. are predominant crop production systems with a little, if any, recycling of organic matter. Data from the long term experiments on major rainfed production systems in India show that higher amount of crop residue C input (Mg/ha/y) return back to soil in soybean-safflower (3.37) system practiced in Vertisol region of central India. Long term addition of chemical fertilizer and organic amendments improved the SOC stock. For every Mg/ha increase in SOC stock in the root zone, there occurs an increase in grain yield (kg/ha) of 13, 101, 90, 170, 145, 18 and 160 for groundnut, finger millet, sorghum, pearl millet, soybean and rice, respectively. Long-term cropping without using any organic amendment and/or mineral fertilizers can severely deplete the SOC stock which is the highest in groundnut-finger millet system (0.92 Mg C/ha/y) in Alfisols. Some agroforestry systems also have a huge potential of C sequestration to the extent of 10Mg/ha/y in short rotation eucalyptus and Leucaena plantations. The critical level of C input requirements for maintaining SOC at the antecedent level ranges from 1.1 to 3.5 Mg C/ha/y and differs among soil type and production systems. National level policy interventions needed to promote sustainable use of soil and water resources include prohibiting residue burning, reducing deforestation, promoting integrated farming systems and facilitating payments for ecosystem services. A wide spread adoption of these measures can improve soil quality through increase in SOC sequestration and improvement in agronomic productivity of

  2. Degradation of N-nitrosodimethylamine (NDMA) in landscape soils.

    Science.gov (United States)

    Yang, W C; Gan, J; Liu, W P; Green, R

    2005-01-01

    N-nitrosodimethylamine (NDMA), a potential carcinogen, was commonly found in treated wastewater as a by-product of chlorination. As treated water is increasingly used for landscape irrigation, there is an imperative need to understand the leaching risk for NDMA in landscape soils. In this study, adsorption and incubation experiments were conducted using landscape soils planted with turfgrass, ground cover, and trees. Adsorption of NDMA was negligibly weak (K(d) NDMA has a high potential for moving with percolating water in these soils. Degradation of NDMA occurred at different rates among these soils. At 21 degrees C, the half-life (t(1/2)) of NDMA was 4.1 d for the ground cover soil, 5.6 d for the turfgrass soil, and 22.5 d for the tree soil. The persistence was substantially prolonged after autoclaving or when incubated at 10 degrees C. The rate of degradation was not significantly affected by the initial NDMA concentration or addition of organic and inorganic nutrient sources. The relative persistence was inversely correlated with soil organic matter content, soil microbial biomass, and soil dehydrogenase activity, suggesting the importance of microorganisms in NDMA degradation in these soils. These results suggest that the behavior of NDMA depends closely on the vegetation cover in a landscape system, and prolonged persistence and increased leaching may be expected in soils with sparse vegetation due to low organic matter content and limited microbial activity.

  3. Collaboration support system for "Phobos-Soil" space mission.

    Science.gov (United States)

    Nazarov, V.; Nazirov, R.; Zakharov, A.

    2009-04-01

    Rapid development of communication facilities leads growth of interactions done via electronic means. However we can see some paradox in this segment in last times: Extending of communication facilities increases collaboration chaos. And it is very sensitive for space missions in general and scientific space mission particularly because effective decision of this task provides successful realization of the missions and promises increasing the ratio of functional characteristic and cost of mission at all. Resolving of this problem may be found by using respective modern technologies and methods which widely used in different branches and not in the space researches only. Such approaches as Social Networking, Web 2.0 and Enterprise 2.0 look most prospective in this context. The primary goal of the "Phobos-Soil" mission is an investigation of the Phobos which is the Martian moon and particularly its regolith, internal structure, peculiarities of the orbital and proper motion, as well as a number of different scientific measurements and experiments for investigation of the Martian environment. A lot of investigators involved in the mission. Effective collaboration system is key facility for information support of the mission therefore. Further to main goal: communication between users of the system, modern approaches allows using such capabilities as self-organizing community, user generated content, centralized and federative control of the system. Also it may have one unique possibility - knowledge management which is very important for space mission realization. Therefore collaboration support system for "Phobos-Soil" mission designed on the base of multilayer model which includes such levels as Communications, Announcement and Information, Data sharing and Knowledge management. The collaboration support system for "Phobos-Soil" mission will be used as prototype for prospective Russian scientific space missions and the presentation describes its architecture

  4. Long-term effects of lowland properties system on soil physicochemical properties and rice yield in Ashanti Region of Ghana

    Energy Technology Data Exchange (ETDEWEB)

    Obalum, S. E.; Oppong, J.; Nwite, J. C.; Watanabe, Y.; Buri, M. M.; Igwe, C. A.; Wakatsuki, T.

    2012-11-01

    Lowland sawah is viewed as a sustainable alternative to traditional rice culture in West Africa. Sawah (a bund-demarcated, puddled, leveled, and water-regulated rice field) has received growing research attention lately, but no data exist yet on the systems long-term agronomic impact. In a clayey inland-valley soil in southern Ghana, 10-year-old sawah plots (OSP), fresh sawah plots (FSP), and non-sawah plots (NSP) were maintained under both ponded and nonponded conditions in 2007. The OSP enhanced soil status of exchangeable nutrients compared to NSP. There were relative improvements in soil bulk density, total porosity, and field moisture content (OSP = FSP > NSP), with clear benefits of ponding over non-ponding in OSP. The NSP was so unsustainable that it showed less favourable values of these variables than an adjacent fallowed plot. These soil variables deteriorated with time, with significant differences in FSP. Soil moisture retention data for tension range of 0-300 kPa depicted the importance of puddling and ponding. During 2001-2009, OSP consistently out-yielded NSP by five times on average. During 2007-2009 when all three plots co-existed, grain yields averaged 5.80, 4.80 and 1.10 Mg ha-1 in OSP, FSP and NSP, respectively. In 2007 yields, OSP minus FSP was higher than NSP; in 2008/2009, the opposite prevailed. These results highlight the agronomic benefits of continuous sawah-based rice production. Although the positive effects of puddling on the soil hydrophysical properties were largely responsible for the wide margin in yield between sawah and traditional systems, other yield-enhancing factors, particularly bunds for water control, were also lacking in the latter. (Author) 37 refs.

  5. Percolation theory and its application for interpretation of soil water retention curves

    International Nuclear Information System (INIS)

    Kodesova, R.

    2004-01-01

    The soil porous system has traditionally been deduced from the soil-water retention curve with the assumption of homogeneity and free accessibility of pores, defined as capillary tubes, from the sink/source of water. But real soil fabric is mostly characterized by aggregates. In this case, the soil porous system cannot be modeled as a homogeneous one. To examine the differences between homogeneous and heterogeneous soil porous systems, we studied two types of soils: sandy soil and coarse sandy soil. We applied image processing filters and the ARC/INFO Grid module to analyze pore sizes in both soils from their electron microscope images taken at two different magnifications. We used the resulting pore-size distribution data to generate 3-D porous media consisting of pores and throats. The homogeneous pore structure was created as a mono-modal pore-throat network with one pore-size distribution. The heterogeneous pore structure was designed as a bi-modal pore-throat network with two pore-size distributions, where the pore sizes were hierarchically arranged in the nodes of the network. We applied the percolation model to simulate water and air displacement in these networks. The distribution of water in the nodes of the networks was studied increasing/decreasing steps of pressure head and the drainage and wetting branches of the retention curves were evaluated. The soil-water retention curves modeled for the mono-modal and bi-modal porous systems had different characters. The simulated shape of the retention curve in the mono-modal case was close to the step-like form of a retention curve characteristic of unstructured soil. The shape of the simulated retention curve in the bi-modal case was smoother, more gradual, and closer to the shape of the retention curve of a real, structured soil. (author)

  6. Using purposeful landscape zoning of Ukraine to improve soil protection system

    Directory of Open Access Journals (Sweden)

    Володимир Тишковець

    2016-10-01

    Full Text Available Basic aspects of Ukrainian landscapes target zoning use for maintenance of soil protection system on agricultural lands have been presented. The analysis of current systems of purposeful zoning of territories in the country and modern approaches to its modernization has been done. The ameliorative functions of forest in accordance with existing main and supportive negative factors, forms and intensiveness of its appearance in concrete types of landscapes have been explained. The questions of forest projection optimization in accordance with natural-climatic conditions of certain regions have been described. The ways of qualitative new use of agroforest ameliorative measures have been determined. The new zoning system on the basis of main soil erosion factors principally differs from the previous systems. The proposed zoning method is characterized by complexity, involving main physical, geographical and agricultural factors in the order of their impact on soil erosion processes. These factors consist of climate (water and temperature regime, relief and character of agricultural use of territory. Meanwhile, other factors (soil, vegetative cover and other are used simultaneously with the main factors. That kind of zoning by the main factors of soil erosion is only the first stage. The second stage should be zoning by types of systems of counter erosion measures. In this article the authors have shown that when choosing agrarian ameliorative methods, the influence on negative factors on agriculture should be considered in the new zoning of the territory. A number of references and fund materials, including those of territorial zoning have been analyzed in the article. Preferences and negative aspects as well as selection of a basis for new agrarian ameliorative zoning of Ukrainian landscapes which includes the full information of factors and conditions of formation and expansion of negative factors for agriculture have been proposed.

  7. Water erosion under simulated rainfall in different soil management systems during soybean growth

    OpenAIRE

    Engel,Fernando Luis; Bertol,Ildegardis; Mafra,Álvaro Luiz; Cogo,Neroli Pedro

    2007-01-01

    Soil management influences soil cover by crop residues and plant canopy, affecting water erosion. The objective of this research was to quantify water and soil losses by water erosion under different soil tillage systems applied on a typical aluminic Hapludox soil, in an experiment carried out from April 2003 to May 2004, in the Santa Catarina highland region, Lages, southern Brazil. Simulated rainfall was applied during five soybean cropstages, at the constant intensity of 64.0 mm h-1. Treat...

  8. Modeling soil processes - are we lost in diversity?

    Science.gov (United States)

    Vogel, Hans-Joerg; Schlüter, Steffen

    2015-04-01

    Soils are among the most complex environmental systems. Soil functions - e.g. production of biomass, habitat for organisms, reactor for and storage of organic matter, filter for ground water - emerge from a multitude of processes interacting at different scales. It still remains a challenge to model and predict these functions including their stability and resilience towards external perturbations. As an inherent property of complex systems it is prohibitive to unravel all the relevant process in all detail to derive soil functions and their dynamics from first principles. Hence, when modeling soil processes and their interactions one is close to be lost in the overwhelming diversity and spatial heterogeneity of soil properties. In this contribution we suggest to look for characteristic similarities within the hyperdimensional state space of soil properties. The underlying hypothesis is that this state space is not evenly and/or randomly populated but that processes of self organization produce attractors of physical, chemical and biological properties which can be identified. (The formation of characteristic soil horizons is an obvious example). To render such a concept operational a suitable and limited set of indicators is required. Ideally, such indicators are i) related to soil functions, ii) are measurable and iii) are integral measures of the relevant physical, chemical and biological soil properties. This would allow for identifying suitable attractors. We will discuss possible indicators and will focus on soil structure as an especially promising candidate. It governs the availability of water and gas, it effects the spatial distribution of organic matter and, moreover, it forms the habitat of soil organisms and it is formed by soil biota. Quantification of soil structural properties became possible only recently with the development of more powerful tools for non-invasive imaging. Future research need to demonstrate in how far these tools can be used to

  9. Two Solutions of Soil Moisture Sensing with RFID for Landslide Monitoring

    Directory of Open Access Journals (Sweden)

    Sérgio Francisco Pichorim

    2018-02-01

    Full Text Available Two solutions for UHF RFID tags for soil moisture sensing were designed and are described in this paper. In the first, two conventional tags (standard transponders are employed: one, placed close to the soil surface, is the sensor tag, while the other, separated from the soil, is the reference for system calibration. By transmission power ramps, the tag’s turn-on power levels are measured and correlated with soil condition (dry or wet. In the second solution, the SL900A chip, which supports up to two external sensors and an internal temperature sensor, is used. An interdigital capacitive sensor was connected to the transponder chip and used for soil moisture measurement. In a novel design for an UHF RFID tag the sensor is placed below the soil surface, while the transponder and antenna are above the soil to improve communication. Both solutions are evaluated practically and results show the presence of water in soil can be remotely detected allowing for their application in landslide monitoring.

  10. Soil-Carbon Measurement System Based on Inelastic Neutron Scattering

    International Nuclear Information System (INIS)

    Orion, I.; Wielopolski, L.

    2002-01-01

    Increase in the atmospheric CO 2 is associated with concurrent increase in the amount of carbon sequestered in the soil. For better understanding of the carbon cycle it is imperative to establish a better and extensive database of the carbon concentrations in various soil types, in order to develop improved models for changes in the global climate. Non-invasive soil carbon measurement is based on Inelastic Neutron Scattering (INS). This method has been used successfully to measure total body carbon in human beings. The system consists of a pulsed neutron generator that is based on D-T reaction, which produces 14 MeV neutrons, a neutron flux monitoring detector and a couple of large NaI(Tl), 6'' diameter by 6'' high, spectrometers [4]. The threshold energy for INS reaction in carbon is 4.8 MeV. Following INS of 14 MeV neutrons in carbon 4.44 MeV photons are emitted and counted during a gate pulse period of 10 μsec. The repetition rate of the neutron generator is 104 pulses per sec. The gamma spectra are acquired only during the neutron generator gate pulses. The INS method for soil carbon content measurements provides a non-destructive, non-invasive tool, which can be optimized in order to develop a system for in field measurements

  11. Soil Quality Indicators as Affected by a Long Term Barley-Maize and Maize Cropping Systems

    Directory of Open Access Journals (Sweden)

    Barbara Manachini

    2009-03-01

    Full Text Available Most soil studies aim a better characterization of the system through indicators. In the present study nematofauna and soil structure were chosen as indicators to be assess soil health as related to agricultural practices. The field research was carried out on the two fodder cropping systems continuous maize (CM, Zea mays L. and a 3-year rotation of silage-maize – silage-barley (Hordeum vulgare L. with Italian ryegrass (R3 and grain-maize maintained in these conditions for 18 years. Each crop system was submitted to two management options: 1 the high input level (H, done as a conventional tillage, 2 the low input level (L, where the tillage was replaced by harrowing and the manure was reduced by 30%. The effects of the two different cropping systems was assessed on soil nematofauna and soil physic parameters (structure or aggregate stability. Comparison was made of general composition, trophic structure and biodiversity of the nematofauna collected in both systems. Differences in nematode genera composition and distribution between the two systems were also recorded. The monoculture, compared to the three year rotation, had a negative influence on the nematofauna composition and its ecological succession. The Structural Stability Index (SSI values indicate that both the cropping systems had a negative effect on the aggregate stability. The results indicate that nematofauna can be used to assess the effects of cropping systems on soil ecosystem, and therefore be considered a good indicator of soil health to integrate information from different chemical or physical indicators.

  12. Soil Quality Indicators as Affected by a Long Term Barley-Maize and Maize Cropping Systems

    Directory of Open Access Journals (Sweden)

    Anna Corsini

    2011-02-01

    Full Text Available Most soil studies aim a better characterization of the system through indicators. In the present study nematofauna and soil structure were chosen as indicators to be assess soil health as related to agricultural practices. The field research was carried out on the two fodder cropping systems continuous maize (CM, Zea mays L. and a 3-year rotation of silage-maize – silage-barley (Hordeum vulgare L. with Italian ryegrass (R3 and grain-maize maintained in these conditions for 18 years. Each crop system was submitted to two management options: 1 the high input level (H, done as a conventional tillage, 2 the low input level (L, where the tillage was replaced by harrowing and the manure was reduced by 30%. The effects of the two different cropping systems was assessed on soil nematofauna and soil physic parameters (structure or aggregate stability. Comparison was made of general composition, trophic structure and biodiversity of the nematofauna collected in both systems. Differences in nematode genera composition and distribution between the two systems were also recorded. The monoculture, compared to the three year rotation, had a negative influence on the nematofauna composition and its ecological succession. The Structural Stability Index (SSI values indicate that both the cropping systems had a negative effect on the aggregate stability. The results indicate that nematofauna can be used to assess the effects of cropping systems on soil ecosystem, and therefore be considered a good indicator of soil health to integrate information from different chemical or physical indicators.

  13. The validation of forensic DNA extraction systems to utilize soil contaminated biological evidence.

    Science.gov (United States)

    Kasu, Mohaimin; Shires, Karen

    2015-07-01

    The production of full DNA profiles from biological evidence found in soil has a high failure rate due largely to the inhibitory substance humic acid (HA). Abundant in various natural soils, HA co-extracts with DNA during extraction and inhibits DNA profiling by binding to the molecular components of the genotyping assay. To successfully utilize traces of soil contaminated evidence, such as that found at many murder and rape crime scenes in South Africa, a reliable HA removal extraction system would often be selected based on previous validation studies. However, for many standard forensic DNA extraction systems, peer-reviewed publications detailing the efficacy on soil evidence is either lacking or is incomplete. Consequently, these sample types are often not collected or fail to yield suitable DNA material due to the use of unsuitable methodology. The aim of this study was to validate the common forensic DNA collection and extraction systems used in South Africa, namely DNA IQ, FTA elute and Nucleosave for processing blood and saliva contaminated with HA. A forensic appropriate volume of biological evidence was spiked with HA (0, 0.5, 1.5 and 2.5 mg/ml) and processed through each extraction protocol for the evaluation of HA removal using QPCR and STR-genotyping. The DNA IQ magnetic bead system effectively removed HA from highly contaminated blood and saliva, and generated consistently acceptable STR profiles from both artificially spiked samples and crude soil samples. This system is highly recommended for use on soil-contaminated evidence over the cellulose card-based systems currently being preferentially used for DNA sample collection. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  14. The Role of Soil Biological Function in Regulating Agroecosystem Services and Sustainability in the Quesungual Agroforestry System

    Science.gov (United States)

    Fonte, S.; Pauli, N.; Rousseau, L.; SIX, J. W. U. A.; Barrios, E.

    2014-12-01

    The Quesungual agroforestry system from western Honduras has been increasingly promoted as a promising alternative to traditional slash-and-burn agriculture in tropical dry forest regions of the Americas. Improved residue management and the lack of burning in this system can greatly impact soil biological functioning and a number of key soil-based ecosystem services, yet our understanding of these processes has not been thoroughly integrated to understand system functionality as a whole that can guide improved management. To address this gap, we present a synthesis of various field studies conducted in Central America aimed at: 1) quantifying the influence of the Quesungual agroforestry practices on soil macrofauna abundance and diversity, and 2) understanding how these organisms influence key soil-based ecosystem services that ultimately drive the success of this system. A first set of studies examined the impact of agroecosystem management on soil macrofauna populations, soil fertility and key soil processes. Results suggest that residue inputs (derived from tree biomass pruning), a lack of burning, and high tree densities, lead to conditions that support abundant, diverse soil macrofauna communities under agroforestry, with soil organic carbon content comparable to adjacent forest. Additionally, there is great potential in working with farmers to develop refined soil quality indicators for improved land management. A second line of research explored interactions between residue management and earthworms in the regulation of soil-based ecosystem services. Earthworms are the most prominent ecosystem engineers in these soils. We found that earthworms are key drivers of soil structure maintenance and the stabilization of soil organic matter within soil aggregates, and also had notable impacts on soil nutrient dynamics. However, the impact of earthworms appears to depend on residue management practices, thus indicating the need for an integrated approach for

  15. Dynamics Coefficient for Two-Phase Soil Model

    Directory of Open Access Journals (Sweden)

    Wrana Bogumił

    2015-02-01

    Full Text Available The paper investigates a description of energy dissipation within saturated soils-diffusion of pore-water. Soils are assumed to be two-phase poro-elastic materials, the grain skeleton of which exhibits no irreversible behavior or structural hysteretic damping. Description of motion and deformation of soil is introduced as a system of equations consisting of governing dynamic consolidation equations based on Biot theory. Selected constitutive and kinematic relations for small strains and rotation are used. This paper derives a closed form of analytical solution that characterizes the energy dissipation during steady-state vibrations of nearly and fully saturated poro-elastic columns. Moreover, the paper examines the influence of various physical factors on the fundamental period, maximum amplitude and the fraction of critical damping of the Biot column. Also the so-called dynamic coefficient which shows amplification or attenuation of dynamic response is considered.

  16. Soil physical indicators of management systems in traditional agricultural areas under manure application

    Directory of Open Access Journals (Sweden)

    Luiz Paulo Rauber

    Full Text Available ABSTRACT Studies of the successive application of manure as fertilizer and its combined effect with long-term soil management systems are important to the identification of the interdependence of physical attributes. The aim of this study was to evaluate changes in the physical properties of a Rhodic Kandiudox under management systems employing successive applications of pig slurry and poultry litter, and select physical indicators that distinguish these systems using canonical discriminant analysis (CDA. The systems consisting of treatments including land use, management and the application time of organic fertilizers are described as follows: silage maize under no-tillage (NT-M7 years; silage maize under conventional tillage (CT-M20 years; annual pasture with chisel plowing (CP-P3 years; annual pasture with chisel plowing (CP-P15 years; perennial pasture without tillage (NT-PP20 years; and no-tillage yerba mate (NT-YM20 years and were compared with native forest (NF and native pasture (NP. Soil samples were collected from the layers at the following depths: 0.0-0.05, 0.05-0.10, and 0.10-0.20 m, and were analyzed for bulk density, porosity, aggregation, flocculation, penetration resistance, water availability and total clay content. Canonical discriminant analysis was an important tool in the study of physical indicators of soil quality. Organic fertilization, along with soil management, influences soil structure and its porosity. Total porosity was the most important physical property in the distinction of areas with management systems and application times of manure for the 0.0-0.05 and 0.10-0.20 m layers. Soil aeration and micropores differentiated areas in the 0.05-0.10 m layer. Animal trampling and machinery traffic were the main factors inducing compaction of this clayey soil.

  17. Pressure, O2, and CO2, in aquatic Closed Ecological Systems

    Science.gov (United States)

    Taub, Frieda B.; McLaskey, Anna K.

    2013-03-01

    Pressure increased during net photosynthetic O2 production in the light and decreased during respiratory O2 uptake during the dark in aquatic Closed Ecological Systems (CESs) with small head gas volumes. Because most CO2 will be in the liquid phase as bicarbonate and carbonate anions, and CO2 is more soluble than O2, volumes of gaseous CO2 and gaseous O2 will not change in a compensatory manner, leading to the development of pressure. Pressure increases were greatest with nutrient rich medium with NaHCO3 as the carbon source. With more dilute media, pressure was greatest with NaHCO3, and less with cellulose or no-added carbon. Without adequate turbulence, pressure measurements lagged dissolved O2 concentrations by several hours and dark respiration would have been especially underestimated in our systems (250-1000 ml). With adequate turbulence (rotary shaker), pressure measurements and dissolved O2 concentrations generally agreed during lights on/off cycles, but O2 measurements provided more detail. At 20 °C, 29.9 times as much O2 will distribute into the gas phase as in the liquid, per unit volume, as a result of the limited solubility of O2 in water and according to Henry's Law. Thus even a small head gas volume can contain more O2 than a larger volume of water. When both dissolved and gaseous O2 and CO2 are summed, the changes in Total O2 and CO2 are in relatively close agreement when NaHCO3 is the carbon source. These findings disprove an assumption made in some of Taub's earlier research that aquatic CESs would remain at approximately atmospheric pressure because approximately equal molar quantities of O2 and CO2 would exchange during photosynthesis and respiration; this assumption neglected the distribution of O2 between water and gas phases. High pressures can occur when NaHCO3 is the carbon source in nutrient rich media and if head-gas volumes are small relative to the liquid volume; e.g., one "worse case" condition developed 800 mm Hg above atmospheric

  18. Formulations of the closed-shell interactions in endohedral systems

    Czech Academy of Sciences Publication Activity Database

    Wang, C.; Straka, Michal; Pyykkö, P.

    2010-01-01

    Roč. 12, č. 23 (2010), s. 6187-6203 ISSN 1463-9076 R&D Projects: GA ČR GA203/09/2037 Grant - others:7th Framework Program(XE) 230955 Institutional research plan: CEZ:AV0Z40550506 Keywords : endohedral systems * closed-shell interactions * one-center expansion Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.454, year: 2010

  19. A case study for evaluating potential soil sensitivity in aridland systems.

    Science.gov (United States)

    Peterman, Wendy L; Ferschweiler, Ken

    2016-04-01

    Globally, ecosystems are subjected to prolonged droughts and extreme heat events, leading to forest die-offs and dominance shifts in vegetation. Some scientists and managers view soil as the main resource to be considered in monitoring ecosystem responses to aridification. As the medium through which precipitation is received, stored, and redistributed for plant use, soil is an important factor in the sensitivity of ecosystems to a drying climate. This study presents a novel approach to evaluating where on a landscape soils may be most sensitive to drying, making them less resilient to disturbance, and where potential future vegetation changes could lead to such disturbance. The drying and devegetation of arid lands can increase wind erosion, contributing to aerosol and dust emissions. This has implications for air quality, human health, and water resources. This approach combines soil data with vegetation simulations, projecting future vegetation change, to create maps of potential areas of concern for soil sensitivity and dust production in a drying climate. Consistent with recent observations, the projections show shifts from grasslands and woodlands to shrublands in much of the southwestern region. An increase in forested area occurs, but shifts in the dominant types and spatial distribution of the forests also are seen. A net increase in desert ecosystems in the region and some changes in alpine and tundra ecosystems are seen. Approximately 124,000 km(2) of soils flagged as "sensitive" are projected to have vegetation change between 2041 and 2050, and 82,927 km(2) of soils may become sensitive because of future vegetation changes. These maps give managers a way to visualize and identify where soils and vegetation should be investigated and monitored for degradation in a drying climate, so restoration and mitigation strategies can be focused in these areas. © 2015 SETAC.

  20. The Soil-Land use System in a Sand Spit Area in the Semi-Arid ...

    African Journals Online (AJOL)

    The Soil-Land use System in a Sand Spit Area in the Semi-Arid Coastal Savanna Region of Ghana – Development, Sustainability and Threats. ... The investigation comprises soil profile descriptions and analyses on the dominant soil type on the sand spit, measurement of electrical conductivity of well water and in the soil, ...

  1. Continuous soil monitoring and inventory of soils as part of the soil information system

    International Nuclear Information System (INIS)

    Schilling, B.

    1993-01-01

    The Bavarian Geological State office conducted a soil inventory and continuous soil monitoring programme. In order to make permanent monitoring feasible the Bavarian Geological State office developed a special concept. This concept of site selection, commissioning, sampling and analysis is described in this paper. The results of first studies of the three permanent soil monitoring areas in the Alpine region shows that only on the Gotzenalm in the national park in Berchtegaden there are significant accumulations of Cs-137 and of some other typically anthropogenic heavy metals in the top soil. Organic pollution is small in all three areas. (orig./EW) [de

  2. Event-scale soil moisture dynamics in open evergreen woodlands of southwest Spain

    Science.gov (United States)

    Lozano-Parra, F. J.; Schnabel, S.; Gómez-Gutiérrez, Á.

    2012-04-01

    soil layer and with rainfall amounts of less than 5 mm, below the tree canopy only few events (15%) produced a notable response in soil moisture, as opposed to the grasslands (42%), which points to the role of rainfall interception by the tree. Furthermore, at greater soil depth low rainfall events only produced an increase of water content in few occasions. This fact is important because more than 50% of the events registered less than 5 mm of rainfall. Soil moisture dynamics were directly related with the wetting process, which varied according to soil cover and its antecedent water content, the characteristics of the rainfall event and the soil depth considered. In the uppermost soil layer of the grassland 86% of the maximum soil moisture values were registered during the event, whereas below the tree canopy the increase was slower and maximum values were registered at the end or after the rainfall event. At depth water dynamics were fairly similar with respect to vegetation cover, depending closely on the antecedent rainfall amounts. Furthermore, abrupt increases of soil moisture were observed during some events, presumably related with preferential flow through macropores.

  3. Soil color - a window for public and educators to understands soils

    Science.gov (United States)

    Libohova, Zamir; Beaudette, Dylan; Wills, Skye; Monger, Curtis; Lindbo, David

    2017-04-01

    Soil color is one of the most visually striking properties recorded by soil scientists around the world. Soil color is an important characteristic related to soil properties such organic matter, parent materials, drainage. It is a simplified way for the public and educators alike to understand soils and their functions. Soil color is a quick measurement that can be recorded by people using color charts or digital cameras, offering an opportunity for the citizen science projects to contribute to soil science. The US Soil Survey has recorded soil colors using Munsell color system for over 20,000 soil types representing a wide range of conditions throughout the Unites States. The objective of this research was to generate a US soil color map based on color descriptions from the Official Series Descriptions (OSDs). A color calculator developed in R and ArcMap were used to spatially display the soil colors. Soil colors showed vertical trends related to soil depth and horizontal trends related to parent material and climate. Soil colors represent development processes depending upon environment and time that have influenced their appearance and geographic distribution. Dark colors represent soils that are rich in organic matter, such as the soils of the Midwest USA, which are some of the most fertile soils in the world. These soils are relatively "young" in that they developed over the last 20,000 years in materials left behind after continental Glaciers retreated and reflect long- term prairie vegetation that dominated this area prior to European settlements. Dark soils of the Pacific Northwest reflect the influence of forests (and volcanic activity) but are shallower and less fertile than the deep dark Midwest soils. Soils of the eastern and southern Coastal Plains are older and are enriched with iron oxides ('rust') which gives them their red coloring. Soils of flood plains, like the broad Mississippi Valley, have multi-colored soils that reflect the process of

  4. Dynamic modeling and response of soil-wall systems

    International Nuclear Information System (INIS)

    Veletsos, A.S.; Younan, A.H.

    1993-10-01

    The study reported herein is the third in a series of investigations motivated by need to gain improved understanding of the responses to earthquakes of deeply embedded and underground tanks storing radioactive wastes, and to develop rational but simple methods of analysis and design for such systems. Following a brief review of the errors that may result from the use of a popular model for evaluating the dynamic soil forces induced in a base-excited rigid wall retaining an elastic stratum, the sources of the errors are identified and a modification is proposed which defines correctly the action of the system. In the proposed modification, the stratum is modeled by a series of elastically supported, semi-infinite horizontal bars with distributed mass instead of massless springs. The concepts involved are introduced by reference to a system composed of a fixed-based wall and a homogeneous elastic stratum, and are then applied to the analysis of more complex soil-wall systems. Both harmonic and transient excitations are considered, and comprehensive numerical solutions are presented which elucidate the actions involved and the effects and relative importance of the relevant parameters

  5. Interactions of low-level, liquid radioactive wastes with soils. 1. Behavior of radionuclides in soil-waste systems

    International Nuclear Information System (INIS)

    Fowler, E.B.; Essington, E.H.; Polzer, W.L.

    1981-01-01

    The characteristics of radioactive wastes and soils vary over a wide range. Liquid radioactive waste entering the environment will eventually contact the soil or geological matrix; interactions will be determined by the chemical and physical nature of the liquid, as well as the soil matrix. We report here the results from an investigation of certain of those characteristics as they relate to retention of radionuclides by soils. Three fractions were demonstrated in the waste as filterable, soluble-sorbable, and soluble-nonsorbable; the physical nature of each fraction was demonstrated using autoradiographic techniques. Isotopes of plutonium and uranium and americium-241 in the soluble fraction of the waste were shown to have a negative charge as determined by ion exchange techniques. In the soil-waste systems, the net charge for those radionuclides was shown to change from predominantly negative to predominantly positive. Nevertheless, cesium-137 was shown to be predominantly positited by TVA and approved by NRC (formerly AEC) since June 1973. This report is based upon the revisions, approved through the end of this reporting period

  6. Chromium in soil layers and plants on closed landfill site after landfill leachate application.

    Science.gov (United States)

    Zupancic, Marija; Justin, Maja Zupancic; Bukovec, Peter; Selih, Vid Simon

    2009-06-01

    Landfill leachate (LL) usually contains low concentrations of heavy metals due to the anaerobic conditions in the methanogenic landfill body after degradation of easily degradable organic matter and the neutral pH of LL, which prevents mobilization and leaching of metals. Low average concentrations of metals were also confirmed in our extensive study on the rehabilitation of an old landfill site with vegetative landfill cover and LL recirculation after its treatment in constructed wetland. The only exception was chromium (Cr). Its concentrations in LL ranged between 0.10 and 2.75 mg/L, and were higher than the concentrations usually found in the literature. The objectives of the study were: (1) to understand why Cr is high in LL and (2) to understand the fate and transport of Cr in soil and vegetation of landfill cover due to known Cr toxicity to plants. The total concentration of Cr in LL, total and exchangeable concentrations of Cr in landfill soil cover and Cr content in the plant material were extensively monitored from May 2004 to September 2006. By obtained data on Cr concentration in different landfill constituents, supported with the data on the amount of loaded leachate, amount of precipitation and potential evapotranspiration (ETP) during the performance of the research, a detailed picture of time distribution and co-dependency of Cr is provided in this research. A highly positive correlation was found between concentrations of Cr and dissolved organic carbon (r=0.875) in LL, which indicates the co-transport of Cr and dissolved organic carbon through the system. Monitoring results showed that the substrate used in the experiment did not contribute to Cr accumulation in the landfill soil cover, resulting in percolation of a high proportion of Cr back into the waste layers and its circulation in the system. No negative effects on plant growth appeared during the monitoring period. Due to low uptake of Cr by plants (0.10-0.15 mg/kg in leaves and 0.05-0.07 mg

  7. Soil microbial respiration beneath Stipa tenacissima L. and in surrounding bare soil

    Directory of Open Access Journals (Sweden)

    Irena Novosádová

    2011-01-01

    Full Text Available Open steppes dominated by Stipa tenacissima L. constitute one of the most representative ecosystems of the semi-arid zones of Eastern Mediterranean Basin (Iberian Peninsula, North of Africa. Ecosystem functioning of these steppes is strongly related to the spatial pattern of grass tussocks. Soils beneath Stipa tenacissima L. grass show different fertility and different microclimatic conditions than in surrounding bare soil. The objective of this study was to assess the effect of Stipa tenacissima L. on the key soil microbial activities under controlled incubation conditions (basal and potential respiration. Basal and potential microbial respirations in the soils beneath Stipa tenacissima L. were, in general, not significantly different from the bare soils. The differences were less than 10%. Significantly less ethylene produced by microbial activity in soils beneath Stipa tenacissima L. after the addition of glucose could indicate the dependence of rhizospheric microbial communities on available carbon compounds. It can be concluded, that the soil respiration in semi-arid Mediterranean ecosystems is not necessarily associated with the patchy plant distribution and that some microbial activities characteristics can be unexpectedly homogenous.

  8. Soil and Crop management: Lessons from the laboratory biosphere 2002-2004

    Science.gov (United States)

    Silverstone, S.; Nelson, M.; Alling, A.; Allen, J.

    During the years 2002 and 2003, three closed system experiments were carried out in the "Laboratory Biosphere" facility located in Santa Fe, New Mexico. The program involved experimentation with "Hoyt" Soy Beans, USU Apogee Wheat and TU-82-155 sweet potato using a 5.37 m2 soil planting bed which was 30 cm deep. The soil texture, 40% clay, 31% sand and 28% silt (a clay loam), was collected from an organic farm in New Mexico to avoid chemical residues. Soil management practices involved minimal tillage, mulching and returning crop residues to the soil after each experiment. Between experiment #2 and #3, the top 15 cm of the soil was amended using a mix of peat moss, green sand, humates and pumice to improve soil texture, lower soil pH and increase nutrient availability. Soil analyses for all three experiments are presented to show how the soils have changed with time and how the changes relate to crop selection and rotation, soil selection and management, water management and pest control. The experience and information gained from these experiments are being applied to the future design of the Mars On Earth facility.

  9. C and N content in density fractions of whole soil and soil size fraction under cacao agroforestry systems and natural forest in Bahia, Brazil.

    Science.gov (United States)

    Rita, Joice Cleide O; Gama-Rodrigues, Emanuela Forestieri; Gama-Rodrigues, Antonio Carlos; Polidoro, Jose Carlos; Machado, Regina Cele R; Baligar, Virupax C

    2011-07-01

    Agroforestry systems (AFSs) have an important role in capturing above and below ground soil carbon and play a dominant role in mitigation of atmospheric CO(2). Attempts has been made here to identify soil organic matter fractions in the cacao-AFSs that have different susceptibility to microbial decomposition and further represent the basis of understanding soil C dynamics. The objective of this study was to characterize the organic matter density fractions and soil size fractions in soils of two types of cacao agroforestry systems and to compare with an adjacent natural forest in Bahia, Brazil. The land-use systems studied were: (1) a 30-year-old stand of natural forest with cacao (cacao cabruca), (2) a 30-year-old stand of cacao with Erythrina glauca as shade trees (cacao + erythrina), and (3) an adjacent natural forest without cacao. Soil samples were collected from 0-10 cm depth layer in reddish-yellow Oxisols. Soil samples was separated by wet sieving into five fraction-size classes (>2000 μm, 1000-2000 μm, 250-1000 μm, 53-250 μm, and 2000 μm) mixed with macroaggregates (32-34%), and microaggregates (1-1.3%). Soil organic carbon (SOC) and total N content increased with increasing soil size fraction in all land-use systems. Organic C-to-total N ratio was higher in the macroaggregate than in the microaggregate. In general, in natural forest and cacao cabruca the contribution of C and N in the light and heavy fractions was similar. However, in cacao + erythrina the heavy fraction was the most common and contributed 67% of C and 63% of N. Finding of this study shows that the majority of C and N in all three systems studied are found in macroaggregates, particularly in the 250-1000 μm size aggregate class. The heavy fraction was the most common organic matter fraction in these soils. Thus, in mature cacao AFS on highly weathered soils the main mechanisms of C stabilization could be the physical protection within macroaggregate structures thereby

  10. [Investigation and analysis of heavy metal pollution related to soil-Panax notoginseng system].

    Science.gov (United States)

    Chen, Lu; Mi, Yan-Hua; Lin, Xin; Liu, Da-Hui; Zeng, Min; Chen, Xiao-Yan

    2014-07-01

    In this study, five heavy metals contamination of soil and different parts of Panax notoginseng in the plantation area was investigated. Analysis of heavy metals correlation between the planting soil and P. notoginseng; and the absorption and accumulation characteristics and translocation of soil heavy metals by P. notoginseng plants was revealed. Through field investigation and laboratory analytical methods, analysis of China's 30 different soil P. notoginseng origin and content of heavy metals in five different parts of the P. notoginseng plant content of heavy metals. The results revealed that the soil heavy metals should not be neglected in the plantation area Referring to the national soil quality standards (GB15608-1995), the excessive degree of soil heavy metals pollution showed Hg > As > Cd > Cr in the plantation area, and Pb content of soil was in the scope of the standard. Refer to 'Green Industry Standards for Import and Export of Medical Plants and Preparations', the excessive degree of heavy metals content of P. notoginseng plants showed As > Pb > Cr > Cd, and Hg content of plants was in the scope of the standard. Concentrations of five heavy metals of underground parts of P. notoginseng plants are higher than aboveground, and heavy metals elements are more concentrated in the root, followed by the rhizome of P. notoginseng plants. Heavy metal accumulation characteristics of the different parts of the P. notoginseng of the overall performance is the root > the rhizome > the root tuber > leaves > stems. From the point of view BCF value analysis of various parts of the P. notoginseng plants to absorb heavy metals in soil, BCF values of all samples were less than 1, description P. notoginseng not belong Hyperaccumulator. From the view of transportation and related analysis of the soil-P. notoginseng systems, the rhizome of P. notoginseng and the content of As and Cr in soil was significantly correlated, the root of P. notoginseng and the content of Cd in

  11. The impact of co-contaminants and septic system effluent quality on the transport of estrogens and nonylphenols through soil.

    Science.gov (United States)

    Stanford, Benjamin D; Amoozegar, Aziz; Weinberg, Howard S

    2010-03-01

    The impact that varying qualities of wastewater may have on the movement of steroid estrogens through soils into groundwater is little understood. In this study, the steroid estrogens 17beta-estradiol (E2) and estrone (E1) were followed through batch and column studies to examine the impact that organic wastewater constituents from on-site wastewater treatment systems (i.e., septic systems or decentralized systems) may have on influencing the rate of transport of estrogens through soils. Total organic carbon (TOC) content (as a surrogate indicator of overall wastewater quality) and the presence of nonyl-phenol polyethoxylate surfactants (NPEO) at concentrations well below the critical micelle concentration were independently shown to be indicative of earlier breakthrough and less partitioning to soil in batch and column experiments. Both NPEO and wastewater with increasing TOC concentrations led to shifts in the equilibrium of E1 and E2 towards the aqueous phase and caused the analytes to have an earlier breakthrough than in control experiments. The presence of nonylphenols, on the other hand, did not appreciably impact partitioning of E1 or E2. Biodegradation of the steroids in soil was also lower in the presence of septic tank effluents than in an organic-free control water. Furthermore, the data indicate that the rate of movement of E1 and E2 present in septic tank effluent through soils and into groundwater can be decreased by removing the NPEOs and TOC through wastewater treatment prior to sub-surface disposal. This study offers some insights into mechanisms which impact degradation, transformation, and retardation, and shows that TOC and NPEO surfactants play a role in estrogen transport. Copyright 2009 Elsevier Ltd. All rights reserved.

  12. The deployment of an innovative real-time radiological soil characterization system

    International Nuclear Information System (INIS)

    Allen, David; Danahy, Raymond; Laird, Gregory; Seiller, Dale; White, Joan; Janke, Robert

    2000-01-01

    Fluor Fernald Inc., in conjunction with partners from Argonne National Laboratory, the Department of Energy's Environmental Measurements Laboratory, and Idaho National Engineering and Environmental Laboratory, has developed a program for characterizing radiological contaminants in soil in real time. The soil characterization system in use at the Fernald Environmental Management Project (FEMP) for over three years combines gamma ray spectrometry equipment with other technologies to produce a system that can scan large areas of ground and produce color coded maps which display quantitative information regarding isotopic contamination patterns. Software running on a battery powered lap-top computer, is used to control acquisition of gamma spectral data to link the spectral Information with precise detector position measurements from Global Positioning System (GPS) satellites, and to control transmission of data to a central station or van via a wireless Ethernet link where Surfer6 mapping software is used to produce maps showing the position and amount of each target analyte. Either sodium iodide (NaI) gamma ray detectors mounted on three different vehicles for mobile measurements or stationary tripod-mounted hyper-pure germanium (HPGe) detectors can be used in this system to radiologically characterize soil. The operational and performance characteristics, as well as the strengths and limitations of each of these units, will be described. The isotopic information generated by this system can be made available to remediation project mangers within an hour after the completion of a scan to aid in determination of excavation footprints, segregation of contaminated soil and verification of contamination removal. The immediate availability of radiological characterization data made possible by this real-time scanning system has allowed Fluor Fernald to accelerate remediation schedules and reduce costs by avoiding excavation delays and expensive and time consuming

  13. Matching soil salinization and cropping systems in communally managed irrigation schemes

    Science.gov (United States)

    Malota, Mphatso; Mchenga, Joshua

    2018-03-01

    Occurrence of soil salinization in irrigation schemes can be a good indicator to introduce high salt tolerant crops in irrigation schemes. This study assessed the level of soil salinization in a communally managed 233 ha Nkhate irrigation scheme in the Lower Shire Valley region of Malawi. Soil samples were collected within the 0-0.4 m soil depth from eight randomly selected irrigation blocks. Irrigation water samples were also collected from five randomly selected locations along the Nkhate River which supplies irrigation water to the scheme. Salinity of both the soil and the irrigation water samples was determined using an electrical conductivity (EC) meter. Analysis of the results indicated that even for very low salinity tolerant crops (ECi water was suitable for irrigation purposes. However, root-zone soil salinity profiles depicted that leaching of salts was not adequate and that the leaching requirement for the scheme needs to be relooked and always be adhered to during irrigation operation. The study concluded that the crop system at the scheme needs to be adjusted to match with prevailing soil and irrigation water salinity levels.

  14. Simulating soil C stability with mechanistic systems models: a multisite comparison of measured fractions and modelled pools

    Science.gov (United States)

    Robertson, Andy; Schipanski, Meagan; Sherrod, Lucretia; Ma, Liwang; Ahuja, Lajpat; McNamara, Niall; Smith, Pete; Davies, Christian

    2016-04-01

    .0 tC ha-1 yr-1. At the US site, however, topsoil C sequestration was less consistent noting considerable variation over the 12 years of measured data. Both sites showed noteworthy discrepancies when model-simulated C was compared with measured C. While all three models were able to simulate the bulk C stocks within reasonable degrees of uncertainty, the accuracy broke down considerably when this bulk soil was split into fractions/pools. Using the data collected and accounting for the differences in model structure, we present potential next steps in model development as well as the variables that should be measured when aiming to reduce the uncertainties inherent in mechanistic systems models. References 1 - Zimmermann et al., 2007. Measured soil organic matter fractions can be related to pools in the RothC model. European Journal of Soil Science, 58:658-667.

  15. Measurements of Plutonium and Americium in Soil Samples from Project 57 using the Suspended Soil Particle Sizing System (SSPSS)

    International Nuclear Information System (INIS)

    John L. Bowen; Rowena Gonzalez; David S. Shafer

    2001-01-01

    As part of the preliminary site characterization conducted for Project 57, soils samples were collected for separation into several size-fractions using the Suspended Soil Particle Sizing System (SSPSS). Soil samples were collected specifically for separation by the SSPSS at three general locations in the deposited Project 57 plume, the projected radioactivity of which ranged from 100 to 600 pCi/g. The primary purpose in focusing on samples with this level of activity is that it would represent anticipated residual soil contamination levels at the site after corrective actions are completed. Consequently, the results of the SSPSS analysis can contribute to dose calculation and corrective action-level determinations for future land-use scenarios at the site

  16. Nexus Thinking on Soil Carbon Dynamics and Soil Health

    Science.gov (United States)

    Lal, R.

    2016-12-01

    Anthropocene is driven by global population of 7.5 billion in 2016, increasing annually by 80 million and projected to be 9.7 billion by 2050. The ecological impact (I=PAT, where P is population, A is affluence, and T is technology) of the population is similar to that of a geological force. Thus, humanity's impact is driven by demands for food, water, energy, and services derived from soil. Soil health, its capacity to function as a vital living system, is determined by quantity and quality of soil organic carbon (SOC) in the root zone ( 50cm). Maintenance of SOC at above the threshold level (1.5 to 2.0% by weight in the root zone) is critical to performing numerous ecosystem services for human wellbeing and nature conservancy. These services and functions strongly depend on nexus or inter-connectivity of biological processes within the pedosphere. The nexus is strongly governed by coupled biogeochemical cycling of water (H2O), carbon (C), nitrogen (N), phosphorus (P) and sulfur (S). Further, it is the nexus between pedological and biological processes that renews and purifies water by denaturing and filtering pollutants; circulates C among biotic and abiotic pools in close association with other elements (N, P, S); provides habitat and energy source for soil biota (macro, meso, and micro flora and fauna), facilitates exchanges of gases between soil and the atmosphere and moderates climate, and creates favorable rhizospheric processes that promote plant growth and enhance net primary productivity. Soil health, governed by SOC quality and quantity, determines the provisioning of numerous ecosystem services and the importance of nexus thinking is highlighted by the truism that "health of soil, plants, animals, human and ecosystem is one and indivisible." The sequestration of SOC depends on land use and soil management strategies which create a positive C budget. Thus, input of biomass-C into the soil must exceed the losses by erosion, mineralization and leaching

  17. Soil chemical atributtes on brachiaria spp in integrated crop livestock system

    Directory of Open Access Journals (Sweden)

    Valdinei Tadeu Paulino

    2013-12-01

    Full Text Available Integrated crop-livestock systems have attracted more interest in the last few years due to their capacity of improving stability and sustainability of agricultural systems when compared to more specialized production ones. The crop-livestock integration is an effective technique, but complex to maintain pasture productivity and its recovery, whose efficiency depends on soil physical management and its chemical fertility. Regarding the soil fertility, the corrective practices generally begin with the liming due to the high acidity of most Brazilian soils and low levels of Ca and Mg in the exchange complex and high Al saturation. In areas of crop-livestock systems, liming corrects the surface acidity potential. However, this practice can leave the subsoil with excess aluminum and lack of calcium, which inhibit root growth and affect the absorption of water and nutrients. The application of gypsum allows the improvement of the subsoil, reducing Al saturation and increasing levels of calcium and sulfur. The aim of this study was to investigate changes in the soil chemical properties of a Haplorthox soil in integrated crop-livestock system (ICL with Brachiaria brizantha cv. Marandu and Piatã, Brachiaria ruziziensis with gypsum and liming application. This study was conducted at the Instituto de Zootecnia, Nova Odessa/SP, a pasture established on a soil with medium texture (61.4% sand, silt 14.6% and 24.0% clay. The treatment plots consisted on integration crop-livestock (ICL cultivated - maize and B. Marandu,  ICL - maize and B. ruziziensis, ICL - maize and B. Piatã and an untreated control group (control - without liming and fertilization grazed pasture throughout the year, located immediately adjacent to the ICL evaluation, which was cultivated for 25 years with B. brizantha cv. Marandu. All pastures were desiccated in October with glyphosate-based herbicide (4 liters per hectare. Then gypsum (1.2 Mg ha-1 and liming (1.2 Mg ha-1 were applied

  18. A novel baiting microcosm approach used to identify the bacterial community associated with Penicillium bilaii hyphae in soil

    DEFF Research Database (Denmark)

    Ghodsalavi, Behnoushsadat; Svenningsen, Nanna Bygvraa; Hao, Xiuli

    2017-01-01

    It is important to identify and recover bacteria associating with fungi under natural soil conditions to enable eco-physiological studies, and to facilitate the use of bacterial-fungal consortia in environmental biotechnology. We have developed a novel type of baiting microcosm, where fungal hyphae...... interact with bacteria under close-to-natural soil conditions; an advantage compared to model systems that determine fungal influences on bacterial communities in laboratory media. In the current approach, the hyphae are placed on a solid support, which enables the recovery of hyphae with associated...... bacteria in contrast to model systems that compare bulk soil and mycosphere soil. We used the baiting microcosm approach to determine, for the first time, the composition of the bacterial community associating in the soil with hyphae of the phosphate-solubilizer, Penicillium bilaii. By applying...

  19. Evaluation of zinc oxide nanoparticle toxicity in sludge products applied to agricultural soil using multispecies soil systems.

    Science.gov (United States)

    Fernández, María Dolores; Alonso-Blázquez, María Nieves; García-Gómez, Concepción; Babin, Mar

    2014-11-01

    To study the environmental impact of nanoparticles, the sludges of wastewater (WWTS) and water treatment (WTS) plants enriched with ZnO nanoparticles were added to agricultural soil, and the toxic effects of the nanoparticles were studied using a microcosm system based on the soil. The WWTS treated soils were characterised by statistically significant decreases (psoils, significant reductions (psoil phosphatase enzymatic activity decreased significantly (psoils), along with statistically significant dose-related inhibition responses on total glutathione cell content, and statistically significant dose-related induction responses on the glutathione S-transferase enzyme activity and the reactive oxygen species generation on the RTG-2 fish cell line. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Monitoring and energetic performance of two similar semi-closed greenhouse ventilation systems

    International Nuclear Information System (INIS)

    Coomans, Mathias; Allaerts, Koen; Wittemans, Lieve; Pinxteren, Dave

    2013-01-01

    Highlights: • Measurements on two semi-closed greenhouses and two traditional open greenhouses. • Mechanical and natural ventilation for dehumidification and cooling. • Analyses and comparison of installation controls, indoor climate and energy flows. • Examination of air-to-air heat recuperation efficiency in ventilation unit. • Using the semi-closed systems amounted to energy savings of 13% and 28%. - Abstract: Horticulture is an energy intensive industry when dealing with cold climates such as Western Europe. High energy prices and on-going pressure from international competition are raising demand for energy efficient solutions. In search of reducing greenhouse energy consumption, this study investigates semi-closed systems combining controlled mechanical and natural ventilation with thermal screens. Ventilated greenhouse systems (semi-closed) have been implemented in the greenhouse compartments of two Belgian horticulture research facilities: the Research Station for Vegetable Production Sint-Katelijne-Waver (PSKW) and the Research Center Hoogstraten (PCH). Additionally, two reference compartments were included for comparison of the results. The greenhouses were part of a long-term monitoring campaign in which detailed measurements with a high time resolution were gathered by a central monitoring system. A large amount of data was processed and analysed, including outdoor and indoor climatic parameters, system controls and installation measurements. The ventilated greenhouses obtained energy savings of 13% and 28% for PSKW and PCH respectively, without substantial impact on crop production or indoor climate conditions when compared to the reference compartments. A considerable amount of heat was recovered by the heat recuperation stage in the ventilation unit of PCH, accounting for 12% of the total heat demand. In general, it was demonstrated that the greenhouse heat demand can be reduced significantly by controlled dehumidification with mechanical