WorldWideScience

Sample records for soil gas surveying

  1. Electrical Resistivity Survey For Conductive Soils At Gas Turbine ...

    Ten (10) vertical electrical soundings (VES) using Schlumberger configuration were carried out to delineate subsurface conductive soils for the design of earthling grid for electrical materials installation at the Gas Turbine Station, Ajaokuta, SW Nigeria. Interpretation of the resistivity data revealed three major geoelectric ...

  2. Radon in soil gas survey in Curitiba (Brazil)

    Paschuk, Sergei A.; Correa, Janine Nicolosi; Schelin, Hugo R.; Barbosa, Laercio; Sadula, Tatyana; Matsuzaki, Cristiana A.

    2009-01-01

    This work describes the radon in soil gas measurements performed during the last two years in cooperation between the Laboratory of Applied Nuclear Physics of the Federal University of Technology (UTFPR), the Nuclear Technology Development Center (CDTN) and the Institute of Radiation Protection and Dosimetry (IRD) from the Brazilian Nuclear Energy Commission (CNEN). Following previously concluded measurements of radon concentration in dwellings and the measurements of 222 Rn activity in drinking water collected at artesian bores of Curitiba urban area, present step of activities has been dedicated to measurements of radon concentration in soil gas. Experimental setup was based on the Professional Radon Monitor (ALPHA GUARD) connected to specially developed for such measurements Soil Gas Probe through the air pump and filter system. After the Probe was inserted, the ground has been tamped down around the probe, to prevent air from moving vertically along the outside of the shaft. The equipment was adjusted with air flow of 0.03 L/min and the measurements were performed during 90 min approximately. The 222 Rn concentration levels were detected and analyzed by the computer every 5 minutes using the software DataEXPERT by GENITRON Instruments. Collected average levels of 222 Rn concentration were processed taking into account the internal volume of Soil Probe and connection vessels. Radon sampling was performed at a depth of 50 - 70 cm. Obtained experimental data of radon concentration present rather big variation but correlates perfectly with previously obtained results for 222 Rn activity in drinking water. Further measurements are planned to be performed at other regions of Parana State and will involve the mineral analysis of soil samples. (author)''

  3. Soil-gas radon/helium surveys in some neotectonic areas of NW Himalayan foothills, India

    S. Mahajan

    2010-06-01

    Full Text Available The present research is aimed at accessing the relationship between variation in the soil gases radon (222Rn and helium (4He and recently developed fissures and other neotectonic features in Nurpur and Nadha areas of the NW Himalayas, India. Two soil-gas surveys were conducted on/near known faults to reconfirm their position using soil gas technique and to check their present activity. During these surveys, soil-gas samples were collected along traverses crossing the observed structures. The data analysis reveals that the concentrations of radon and helium along the Dehar lineament and the longitudinal profile (Profile D are very high compared to any other thrust/lineament of the Nurpur area. The Nadha area shows high values of radon and helium concentrations along/near the Himalayan Frontal Fault (HFF as compared to the adjoining areas. This indicates the presence of some buried fault/fault zone running parallel to the HFF, not exposed to the surface and not delineated by satellite data but is geochemically active and might be tectonically active too. Hence, soil helium and radon gas patterns have been combined with morphological and geological observations to supply useful constraints for deformation of tectonic environments.

  4. Preliminary results of soil radon gas survey of the Lake Bosomtwi impact crater

    Preko, S.; Danuor, S.K.; Menyeh, A.

    2004-01-01

    Soil radon gas survey was carried out in the Lake Bosomtwi impact crater area on eight profiles, which ran rapidly toward the end of the crater. One thousand soil samples, each weighing about 100g were acquired at a depth of 20 cm and at regular intervals of 10 m. The radon gas decay rate of the soil samples was then determined in the laboratory using the RDA-200 Radon detector and RDU-200 Degassing unit. It was found that generally areas south and east of the crater, which are severally sheared, faulted and fractured recorded high radon gas decay rates of the order of 800 counts/min whilst relatively undisturbed zones west of the crater recorded lower rates of the order of 20 counts/min. the cause of fracturing, shearing and faulting have been attributed to the effect of the meteorite impact in the Bosomtwi area, and therefore the results indicate that the soil radon gas survey could serve as a useful tool in mapping the impact-related structural characteristics of the crater. (author)

  5. Regional and Detailed Survey for Radon Activities in Soil-Gas and Groundwater in the Okchon Zone, Korea

    Je, H.-K.; Chon, H.-T.

    2012-04-01

    The Okchon zone in Korea provides a typical example of natural geological materials enriched in potentially toxic elements including uranium which is parent nuclide for radon gas. For the purpose of radon radioactivity risk assessment, making the map of radon risk grade from Okchon zone, regional and detailed field surveys were carried out during 3 years. The study area is located in the central part of Korea, called the Okchon zone (about 5,100 km2), which occur in a 80km wide, northeast-trending belt that extends across the Korean Peninsula. The Okchon zone is underlain by metasedimentary rocks of unknown age that are composed mainly of black slate, phyllite, shale, and limestone. The three research areas (defined as Boeun, Chungju, and Nonsan) for detailed survey were selected from the results of regional survey. Results of detailed radon survey indicated a wide range of radon activities for soil-gases (148-1,843 pCi/L) and ground waters (23-5,540 pCi/L). About 15 percent of soil-gas samples exceeded 1,000 pCi/L and 84 percent of ground water samples exceeded the MCL (maximum contaminant level) of drinking water, 300 pCi/L, which proposed by U.S. Environmental Protection Agency in 1999. For detailed survey, radon activities of soil-gas and ground water were classified as bedrock geology, based on 1/50,000 geological map and field research. For soil-gas measurements, mean values of radon activity from black slate-shale (789 pCi/L) were highest among the other base rocks. And for groundwater measurements, mean value of radon activities were decreased in the order of granite (1,345 pCi/L) > black shale-slate (915 pCi/L) > metasediments (617 pCi/L). Result of indoor radon measurement from detailed survey areas showed that about 50% of houses exceeded the indoor guideline, 4 pCi/L. For the radon risk assessment in indoor environment showed that probability of lung cancer risk from the houses located on the granite base rock (3.0×10-2) was highest among the other

  6. Soil Gas Sampling

    Field Branches Quality System and Technical Procedures: This document describes general and specific procedures, methods and considerations to be used and observed when collecting soil gas samples for field screening or laboratory analysis.

  7. Radon in soil gas

    Rector, H.E.

    1990-01-01

    This paper presents the results of a technology review conducted to identify and organize the range of options for measuring radon in soil gas as a means to evaluate radon exposure potential in buildings. The main focus of the review includes identifying the following: Measurement of objectives - the specific parameter(s) that each technology is designed to measure( e.g., soil gas concentration, flux density, etc.); Equipment needs -commercial availability of systems and/or components, specifications for fabricated components; Procedural information - documented elements of field and laboratory methodology and quality assurance; Underlying assumptions - conceptual and mathematical models utilized to convert analytical outcomes to estimators of radon. Basic technologies and field data were examined from a generic perspective (e.g., the common denominators of passive detectors, hollow sampling probes, flux monitors)( as well as specific configurations developed by individual investigators (e.g., sample volume, depth) to develop the basis for separating analytical uncertainties form sampling uncertainties

  8. Survey of selecting the promising drilling points out of the ground survey of the FY 1992 geothermal development promotion survey. Soil gas survey (No.C-1 - Shirotori area); 1992 nendo chinetsu kaihatsu sokushin chosa. Chijo chosa no uchi yubo kussaku chiten sentei chosa (Dojo gas chosa) hokokusho (No. C-1 Shirotori chiiki)

    NONE

    1994-03-01

    As a part of the survey of selecting promising drilling points, survey was made using soil gas to grasp the area of existence of geothermal fluid in the area for careful examination and the locational distribution of fractures controlling the behavior of fluid. In the survey, the concentration of Hg in soil gas/carbon isotopic ratio of CO2 were measured at 247 measuring points. Generally speaking, there existed the hydrothermal fluid along the structure controlling geothermal activities in the area where the concentration of Hg in soil gas is high, and the volcanic gas as a heating source of geothermal fluid was rising in the area where the carbon isotopic ratio is high. In the survey, areas where both the Hg concentration and the carbon isotopic ratio were high were extracted as promising areas where the high temperature geothermal fluid possibly exists. The promising areas extracted were the periphery of the Daiichi (No.1) Shirotori Hot Spring, periphery of KT-4, southern periphery of N4-ST-2, periphery of 54E-OBN-1 - 54E-OBN-2, and periphery of N4-ST-2. Besides, a possibility of existence of geothermal fluid was indicated in the northeast of N4-ST-1 and in the northeast of KT-9. (NEDO)

  9. Soil Gas Sampling Operating Procedure

    EPA Region 4 Science and Ecosystem Support Division (SESD) document that describes general and specific procedures, methods, and considerations when collecting soil gas samples for field screening or laboratory analysis.

  10. Field investigation with regard to the impermeability of clay formations. Helium-4 soil gas surveys in sedimentary basins as a tentative study of secondary permeability in clayey sequences

    Lombardi, S.; Benvegnu, F.; Brondi, A.; Polizzano, C.

    1993-01-01

    This report deals with a tentative study for the detection of the secondary permeability in clayey formations conducted in several sedimentary basins in Central Italy, by means of geochemical methods. The main purposes are: to try a geochemical method, based on the distribution of deep origin gases in soil gas ( 4 He and 222 Rn), to detect buried fault systems and to study the permeability of clay as a potential migration pathway for nuclides of radioactive waste deposits; to verify the effectiveness of this method for the selection of suitable sites for radwaste disposal. This research programme consists in a collaboration between ENEA and the University of Rome within the communitarian programme for the disposal of high level and long-live radwaste. Investigations concerned sedimentary basins filled by sand-clay formations 1000-2000 meters thick and characterized by different tectonic: Era and Chiani-Paglia Valleys (Tuscany and North Latium), structural trenches due to extensive tectonics along the tyrrhenian edge, and Vasto region, a basin in the 'Adriatic foretrench', characterized by compressive tectonics. The investigated areas are near or directly correspond to geothermal fields or to hydrocarbon reservoirs supplying gases which may migrate upward along fractures. Almost 4000 soil gas samples were collected in the three surveyed areas; the sampling density was of about 1.5 points / km 2 , normally used in the regional scale surveys. The obtained results show that the observed helium anomalies are distributed or elongated according to the main tectonic features of the substratum (fault systems, fractures, deep structures); the magnitude of anomalies seems to correlate with the nature of the deep gas reservoir (i.e. oil in Vasto), geothermal reservoir in the Paglia valley. These observations seem to confirm that the presence of deep origin gases in soils is controlled by tectonics. Clay thickness does not significantly control the uprising of deep gases: in

  11. Soil Survey Geographic (SSURGO) - Kinds and Distribution of Soils

    California Natural Resource Agency — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  12. Field survey of Canadian background soils: Implications for a new mathematical gas chromatography-flame ionization detection approach for resolving false detections of petroleum hydrocarbons in clean soils.

    Kelly-Hooper, Francine; Farwell, Andrea J; Pike, Glenna; Kennedy, Jocelyn; Wang, Zhendi; Grunsky, Eric C; Dixon, D George

    2014-08-01

    The reference method for the Canada-wide standard (CWS) for petroleum hydrocarbons (PHCs) in soil provides laboratories with methods for generating accurate and reproducible soil analysis results. The CWS PHC tier 1 generic soil-quality guidelines apply to 4 carbon ranges/fractions: F1 (C6-C10), F2 (C10-C16), F3 (C16-C34), and F4 (>C34). The methods and guidelines were developed and validated for soils with approximately 5% total organic carbon (TOC). However, organic soils have much higher TOC levels because of biogenic organic compounds (BOCs) originating from sources such as plant waxes and fatty acids. Coextracted BOCs can have elevated F2-F4 concentrations, which can cause false exceedances of PHC soil guidelines. The present study evaluated false PHC detections in soil samples collected from 34 background sites. The list of analytes included soil type, TOC, polycyclic aromatic hydrocarbons (PAHs), F2, F3, F4, F3a (C16-C22), and F3b (C22-C34). Soils with 3% to 41% TOC falsely exceeded the CWS PHC 300 mg/kg F3 coarse soil guideline. It was previously demonstrated that clean peat had F2:F3b ratios of less than 0.10, while crude oil spiked peat and spiked sand had higher ratios of greater than 0.10. In the present background study, all of the clean organic soils with at least 300 mg/kg F3 had F2:F3b ratios of less than 0.10, which indicated false guideline exceedances. Clean inorganic soils had low F3 concentrations, resulting in high F2:F3b ratios of greater than 0.10. Validation field studies are required to determine if the F2:F3b 0.10 PHC presence versus absence threshold value is applicable to crude oil- and diesel-contaminated sites. © 2014 SETAC.

  13. VT Data - NRCS Soil Survey Units

    Vermont Center for Geographic Information — (Link to Metadata) This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil...

  14. Soil Survey Geographic (SSURGO) - Magnesic Soils

    California Natural Resource Agency — Magnesic soils is a subset of the SSURGO dataset containing soil family selected based on the magnesic content and serpentinite parent material. The following soil...

  15. Earthworms and the soil greenhouse gas balance

    Lubbers, I.M.

    2014-01-01

    Earthworms play an essential part in determining the greenhouse gas (GHG) balance of soils worldwide. Their activity affects both biotic and abiotic soil properties, which in turn influence soil GHG emissions, carbon (C) sequestration and plant growth. Yet, the balance of earthworms

  16. Soil gas radon response to environmental and soil physics variables

    Thomas, D.M.; Chen, C.; Holford, D.

    1991-01-01

    During the last three years a field study of soil gas radon activities conducted at Poamoho, Oahu, has shown that the primary environmental variables that control radon transport in shallow tropical soils are synoptic and diurnal barometric pressure changes and soil moisture levels. Barometric pressure changes drive advective transport and mixing of soil gas with atmospheric air; soil moisture appears to control soil porosity and permeability to enhance or inhibit advective and diffusive radon transport. An advective barrier test/control experiment has shown that advective exchange of soil gas and air may account for a substantial proportion of the radon loss from shallow soils but does not significantly affect radon activities at depths greater than 2.3 m. An irrigation test/control experiment also suggests that, at soil moisture levels approaching field capacity, saturation of soil macroporosity can halt all advective transport of radon and limit diffusive mobility to that occurring in the liquid phase. The results of the authors field study have been used to further refine and extend a numerical model, RN3D, that has been developed by Pacific Northwest Laboratories to simulate subsurface transport of radon. The field data have allowed them to accurately simulate the steady state soil gas radon profile at their field site and to track transient radon activities under the influence of barometric pressure changes and in response to changes in soil permeability that result from variations in soil moisture levels. Further work is continuing on the model to enable it to properly account for the relative effects of advective transport of soil gas through cracks and diffusive mobility in the bulk soils

  17. Soil cover of gas-bearing areas

    Mozharova, N. V.

    2010-08-01

    Natural soils with disturbed functioning parameters compared to the background soils with conservative technogenic-pedogenic features were distinguished on vast areas above the artificial underground gas storages in the zones of spreading and predominant impact of hydrocarbon gases. The disturbance of the functioning parameters is related to the increase in the methane concentration, the bacterial oxidation intensity and destruction, and the complex microbiological and physicochemical synthesis of iron oxides. The technogenic-pedogenic features include neoformations of bacteriomorphic microdispersed iron oxides. The impurity components consist of elements typical for biogenic structures. New soil layers, horizons, specific anthropogenically modified soils, and soil-like structures were formed on small areas in the industrial zones of underground gas storages due to the mechanical disturbance, the deposition of drilling sludge, and the chemical contamination. Among the soils, postlithogenic formations were identified—chemotechnosols (soddy-podzolic soils and chernozems), as well as synlithogenic ones: strato-chemotechnosols and stratochemoembryozems. The soil-like bodies included postlithogenic soil-like structures (chemotechnozems) and synlithogenic ones (strato-chemotechnozems). A substantive approach was used for the soil diagnostics. The morphological and magnetic profiles and the physical, chemical, and physicochemical properties of the soils were analyzed. The micromorphological composition of the soil magnetic fraction was used as a magnetic label.

  18. Mercury soil surveys: a good reconnaissance tool

    Stone, C.; Ruscetta, C.A.; Foley, D. (eds.)

    1981-05-01

    Three examples of mercury soil surveys are discussed, along with the gravity data. An excellent correlation was found in southern Arizona between buried structures revealed by gravity and mercury soil surveys. The advantages of the latter over the former as a reconnaissance tool are listed. (MHR)

  19. Radon in soil gas in Kosovo.

    Kikaj, Dafina; Jeran, Zvonka; Bahtijari, Meleq; Stegnar, Peter

    2016-11-01

    An assessment of the radiological situation due to exposure to radon and gamma emitting radionuclides was conducted in southern Kosovo. This study deals with sources of radon in soil gas. A long-term study of radon concentrations in the soil gas was carried out using the SSNTDs (CR-39) at 21 different locations in the Sharr-Korabi zone. The detectors were exposed for an extended period of time, including at least three seasonal periods in a year and the sampling locations were chosen with respect to lithology. In order to determine the concentration of the natural radioactive elements 238 U and 226 Ra, as a precursor of 222 Rn, soil samples were collected from each measuring point from a depth of 0.8 m, and measured by gamma spectrometry. The levels (Bq kg -1 ) of naturally occurring radionuclides and levels (kBq m -3 ) of radon in soil gas obtained at a depth 0.8 m of soil were: 21-53 for 226 Ra, 22-160 for 238 U and 0.295-32 for 222 Rn. With respect to lithology, the highest value for 238 U and 226 Ra were found in limestone and the highest value for 222 Rn was found in metamorphic rocks. In addition, the results showed seasonal variations of the measured soil gas radon concentrations with maximum concentration in the spring months. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Carbon cycling and gas exchange in soils

    Trumbore, S.E.

    1989-01-01

    This thesis summaries three independent projects, each of which describes a method which can be used to study the role of soils in regulating the atmospheric concentrations of CO 2 and other trace gases. The first chapter uses the distribution of natural and bomb produced radiocarbon in fractionated soil organic matter to quantify the turnover of carbon in soils. A comparison of 137 Cs and 14 C in the modern soil profiles indicates that carbon is transported vertically in the soil as dissolved organic material. The remainder of the work reported is concerned with the use of inert trace gases to explore the physical factors which control the seasonal to diel variability in the fluxes of CO 2 and other trace gases from soils. Chapter 2 introduces a method for measuring soil gas exchange rates in situ using sulfur hexafluoride as a purposeful tracer. The measurement method uses standard flux box technology, and includes simultaneous determination of the fluxes and soil atmosphere concentrations of CO 2 and CH 4 . In Chapter 3, the natural tracer 222 Rn is used as an inert analog for exchange both in the soils and forest canopy of the Amazon rain forest

  1. International survey on gas technology organizations

    1994-11-01

    The International Survey on Gas Technology Organizations has been prepared by the IEA International Centre for Gas Technology Information. 172 companies and R and D Institutions from 41 countries have contributed to the survey. The objective of the Survey is to develop an overview of identified organizations active in the development of new gas technology. As a quick reference guide the survey offers you short descriptions of a number of the most important organizations within gas technology on a world wide basis. Many R and D institutions around the world are working with topics of relevance to the gas industry. New gas technology draws on many different scientific and technical disciplines. This first issue of the survey includes only a part of the numerous organizations and institutions active within the development of new technology of relevance to the gas industry. The preparation of this survey has been a first step in the development of the information activities of the Centre. The information regarding organizations with R and D activities of relevance to the gas industry will continuously be expanded and updated for internal use in the Centre and will also be available to external users. The Centre plans to establish on-line access to these update versions during 1995. (EG)

  2. Measurements of radon in soil gas

    Paschuk, Sergei A.; Correa, Janine Nicolosi; Schelin, Hugo R.; Barbosa, Laercio; Sadula, Tatyana; Matsuzaki, Cristiana A.

    2009-01-01

    Full text: After the decades of systematic and numerous studies performed at different countries of the World, it has been concluded that radon as well as its progeny is the main cause of lung cancer. It is well known that more than 50% of the effective annual radiation dose received by a human being is related to the radon and its progenies. Among the principle mechanisms that bring the radon inside the dwelling is the soil exhalation as well as exhalation and release from the water. Radon concentration in the soil and its transport (emanation, diffusion, advection and adsorption) to the surface depends on different physical, geological and ambient parameters such as the geology of the area, geochemical composition of the soil, its porosity and permeability, grain size, soil humidity, bottom sediments and inputs from streams, temperature, atmospheric pressure, etc. Since the main part of indoor radon originates in the soil, the measurements of radon concentration in soil gas have to be considered as an important tool and indicator of probable high levels of radon inside the dwellings. Present work describes the radon in soil gas measurements performed during the last two years in cooperation between the Laboratory of Applied Nuclear Physics of the Federal University of Technology (UTFPR), the Nuclear Technology Development Center (CDTN) and the Institute of Radiation Protection and Dosimetry (IRD) from the Brazilian Nuclear Energy Commission (CNEN). Following previously concluded measurements of radon concentration in dwellings and the measurements of 222 Rn activity in drinking water collected at artesian bores of Curitiba urban area, present step of activities has been dedicated to measurements of radon concentration in soil gas. Experimental setup was based on the Professional Radon Monitor (ALPHA GUARD) connected to specially developed for such measurements Soil Gas Probe through the air pump and filter system. The equipment was adjusted with air flow of 0

  3. Supercritical water decontamination of town gas soil

    Kocher, B.S.; Azzam, F.O.; Lee, S.

    1994-01-01

    Town gas sites represent a large environmental problem that exists in more than 2,000 sites across North America alone. The major contaminants in town gas sods are polycyclic aromatic hydrocarbons (PAHs). These are stable compounds that migrate deep into the soil and are traditionally very difficult to remove by conventional remediation processes. Supercritical fluids offer enhanced solvating properties along with reduced mass transfer resistances that make them ideal for removing compounds that are difficult or impossible to remove by conventional processes. Supercritical water is ideal for removing PAHs and other hydrocarbons from soil due to its high solvating power towards most hydrocarbon species. Supercritical water was investigated for its ability to remediate two different town gas sods containing from 3--20 wt% contamination. The sod was remediated in a 300-cc semi-continuous system to a more environmentally acceptable level

  4. (Canada) Oil and gas survey, 1987

    1987-01-01

    This summarizes the financial reporting of a major segment of the oil and gas industry in Canada as shown in annual reports to shareholders for 1986. Annual reports have been surveyed with particular attention to developments in accounting practices in the oil and gas industry during 1986. The survey was not restricted to financial statements and all information presented in the annual reports was considered. Matters of general financial disclosure not unique to the oil and gas industry are not included. Examples quoted from reports covered by this survey are not presented as recommended methods but are illustrations of present practice only. Some illustrations were drawn from oil and gas companies not included in the survey.

  5. Modelling gas markets - a survey

    NONE

    1997-12-31

    This report reviews research of relevance to the analysis of present and future developments of the European natural gas market. The research activities considered are confined to (1) numerical models for gas markets, (2) analyses of energy demand, and (3) analyses of behaviour and cost structures in the transmission and distribution sector. Most of the market models are strictly micro economic and assume perfect competition or a game-theoretical equilibrium. They use sophisticated solution concepts, but very simplified specifications of supply and demand functions. Most of the research on demand is econometric analyses. These have more detailed model specification than have the aggregated market models. It is found, however, that the econometric literature based on neo-classical economics has not yielded unambiguous results and the specifications disregard important real world aspects of gas demand. The section on demand concludes that the extent of the gas grid is an important determinant for gas demand, but there has been virtually no research on what determines this variable. Data about transmission and distribution of gas in Europe is scarce and only a few non-econometric and virtually no econometric analyses are available. However, some conclusions can be made from relevant North American literature: (1) there has been significant autonomous technical progress in the transmission industry, (2) distribution costs strongly depend on geographical and other conditions, and (3) ownership, whether private or public, may be important for distribution costs and pricing policies. 56 refs., 3 figs., 1 tab.

  6. Modelling gas markets - a survey

    1997-01-01

    This report reviews research of relevance to the analysis of present and future developments of the European natural gas market. The research activities considered are confined to (1) numerical models for gas markets, (2) analyses of energy demand, and (3) analyses of behaviour and cost structures in the transmission and distribution sector. Most of the market models are strictly micro economic and assume perfect competition or a game-theoretical equilibrium. They use sophisticated solution concepts, but very simplified specifications of supply and demand functions. Most of the research on demand is econometric analyses. These have more detailed model specification than have the aggregated market models. It is found, however, that the econometric literature based on neo-classical economics has not yielded unambiguous results and the specifications disregard important real world aspects of gas demand. The section on demand concludes that the extent of the gas grid is an important determinant for gas demand, but there has been virtually no research on what determines this variable. Data about transmission and distribution of gas in Europe is scarce and only a few non-econometric and virtually no econometric analyses are available. However, some conclusions can be made from relevant North American literature: (1) there has been significant autonomous technical progress in the transmission industry, (2) distribution costs strongly depend on geographical and other conditions, and (3) ownership, whether private or public, may be important for distribution costs and pricing policies. 56 refs., 3 figs., 1 tab

  7. 7 CFR 611.11 - Soil survey information.

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Soil survey information. 611.11 Section 611.11 Agriculture Regulations of the Department of Agriculture (Continued) NATURAL RESOURCES CONSERVATION SERVICE, DEPARTMENT OF AGRICULTURE CONSERVATION OPERATIONS SOIL SURVEYS Soil Survey Operations § 611.11 Soil survey information. (a) Availability. NRCS...

  8. Soil Survey Geographic (SSURGO) database for Torrance Area, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  9. Soil Survey Geographic (SSURGO) database for Union County, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  10. Soil Survey Geographic (SSURGO) database for Roosevelt County, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  11. Soil Survey Geographic (SSURGO) database for Hidalgo County, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  12. Soil Survey Geographic (SSURGO) database for Luna County, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  13. Soil Survey Geographic (SSURGO) database for Colfax County, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  14. Soil Survey Geographic (SSURGO) database for Guadalupe County, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  15. Soil Survey Geographic (SSURGO) database for Lea County, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  16. Soil Survey Geographic (SSURGO) database for Otero Area, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  17. Soil Survey Geographic (SSURGO) database for Harding County, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  18. Soil Survey Geographic (SSURGO) database for Eddy Area, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  19. Radon chamber for soil gas detectors

    Andersson, P.

    1987-01-01

    Swedish Geological Co (SGAB) has designed and constructed a chamber for the calibration of detectors and instruments intended for the measurement of radon-222 in soil gas. In the chamber radon detectors may be exposed in a model environment which simulates ground conditions with respect to radon concentration, temperature and humidity. Also included in the research project is the development of methods for calibration procedures, together with test measurements. In general, these measurements indicate that the radon detectors tested are sufficiently accurate and reliable for radon measurements in Swedish soils if they are calibrated in an environment which simulates ground conditions. (orig./HP)

  20. Using USDA's National Cooperative Soil Survey Soil Characterization Data to detect soil change: A cautionary tale

    Recently, the USDA-NRCS National Cooperative Soil Survey Soil Characterization Database (NSCD) was reported to provide evidence that total nitrogen (TN) stocks of agricultural soils have increased across the Mississippi basin since 1985. Unfortunately, due to omission of metadata from the NSCD, hist...

  1. Effect of Particle Size and Soil Compaction on Gas Transport Parameters in Variably Saturated, Sandy Soils

    Hamamoto, Shoichiro; Møldrup, Per; Kawamoto, Ken

    2009-01-01

    The soil gas diffusion coefficient (Dp) and air permeability (ka) and their dependency on soil air content ( ) control gas diffusion and advection in soils. This study investigated the effects of average particle size (D50) and dry bulk density ( b) on Dp and ka for six sandy soils under variably...

  2. Canadian oil and gas survey 1998

    Roberge, R.B.

    1998-01-01

    The year 1997 brought record levels of financing for the Canadian oil and gas industry which led to record levels of capital spending and unprecedented merger and acquisition activity. Production records were achieved, but soft commodity prices in the fourth quarter resulted in a significant downturn in the equity markets. El Nino reduced demand for natural gas and heating oil, resulting in increased storage levels for both commodities. Record drilling and capital spending fueled the Canadian oilfield service industry as total market capitalization rose to $10 billion. As for the 1998 outlook, the industry has turned to natural gas as the favoured commodity, as indicated by the conclusion of the Alliance pipeline hearings and the Nova/TCPL merger. This survey presents a review of crude oil and natural gas production, prices, and capital spending for development and exploratory wells, and the financial and operating results for fiscal year 1997 of selected oil and gas companies and income trusts. All listed companies are Canadian public companies, or publicly traded income trusts, traded on one of the country's four major stock exchanges. They are ranked according to gross oil and gas production revenue only (before royalties). Syncrude and oil sands production is also included. The remaining data in the financial statistics tables includes all business segments of each company included. The survey excluded companies that were wholly-owned subsidiaries, divisions or U.S. subsidiaries and private companies. tabs., figs

  3. Observation of radon content in soil gas

    Mino, Kazuo; Nishimura, Susumu

    1979-01-01

    For earthquake prediction, precursory phenomena before the large earthquakes have been investigated in many countries. In China and some other places, they made a success of predictions of the large earthquakes by catching precursory phenomena. Variation of Radon content of underground gas and water is also one of those phenomena. In our country, the decrease of Radon content was observed several days before the large earthquake which occured near Izu Peninsula on January, 14, 1978. We also begin to observe variation of Radon content of underground gas. The purpose of our observation is a study on the Radon gas content before and after earthquakes. According to the results of the test investigation, the change of atmospheric pressure is mutually related with variation of Radon content in soil gas. Effect of atmospheric pressure is about one Eman, which is significant value comparison with the change, before the large earthquake, a few or several Emans. But, when correction of atmospheric pressure's effect was done, the change of Radon content maybe decrease 5/100 Emans. Above result tells the possibility of detecting the precursor of large earthquake, if Radon content change was over a few Emans. (author)

  4. Diffusion probe for gas sampling in undisturbed soil

    Petersen, Søren O

    2014-01-01

    Soil-atmosphere fluxes of trace gases such as methane (CH4) and nitrous oxide (N2O) are determined by complex interactions between biological activity and soil conditions. Soil gas concentration profiles may, in combination with other information about soil conditions, help to understand emission...... controls. This note describes a simple and robust diffusion probe for soil gas sampling as part of flux monitoring programs. It can be deployed with minimum disturbance of in-situ conditions, also at sites with a high or fluctuating water table. Separate probes are used for each sampling depth...... on peat soils used for grazing showed soil gas concentrations of CH4 and N2O as influenced by topography, site conditions, and season. The applicability of the diffusion probe for trace gas monitoring is discussed....

  5. The GBT Diffuse Ionized Gas Survey (GDIGS)

    Luisi, Matteo; Anderson, Loren Dean; Liu, Bin; Bania, Thomas; Balser, Dana; Wenger, Trey; Haffner, Lawrence Matthew

    2018-01-01

    Diffuse ionized gas in the Galactic mid-plane known as the "Warm Ionized Medium" (WIM) makes up ~20% of the gas mass of the Milky Way and >90% of its ionized gas. It is the last major component of the interstellar medium (ISM) that has not yet been studied at high spatial and spectral resolution, and therefore many of its fundamental properties remain unclear. The Green Bank Telescope (GBT) Diffuse Ionized Gas Survey (GDIGS) is a new large survey of the Milky Way disk at C-band (4-8 GHz). The main goals of GDIGS are to investigate the properties of the WIM and to determine the connection between the WIM and high-mass star formation over the Galactic longitude and latitude range of 32 deg > l > -5 deg, |b| resolution of 0.5 km/s and rms sensitivities of ~3 mJy per beam. GDIGS observations are currently underway and are expected to be completed by late 2018. These data will allow us to: 1) Study for the first time the inner-Galaxy WIM unaffected by confusion from discrete HII regions, 2) determine the distribution of the inner Galaxy WIM, 3) investigate the ionization state of the WIM, 4) explore the connection between the WIM and HII regions, and 5) analyze the effect of leaked photons from HII regions on ISM dust temperatures.

  6. LANDSAT-1 data, its use in a soil survey program

    Westin, F. C.; Frazee, C. J.

    1975-01-01

    The following applications of LANDSAT imagery were investigated: assistance in recognizing soil survey boundaries, low intensity soil surveys, and preparation of a base map for publishing thematic soils maps. The following characteristics of LANDSAT imagery were tested as they apply to the recognition of soil boundaries in South Dakota and western Minnesota: synoptic views due to the large areas covered, near-orthography and lack of distortion, flexibility of selecting the proper season, data recording in four parts of the spectrum, and the use of computer compatible tapes. A low intensity soil survey of Pennington County, South Dakota was completed in 1974. Low intensity inexpensive soil surveys can provide the data needed to evaluate agricultural land for the remaining counties until detailed soil surveys are completed. In using LANDSAT imagery as a base map for publishing thematic soil maps, the first step was to prepare a mosaic with 20 LANDSAT scenes from several late spring passes in 1973.

  7. Learning from soil gas change and isotopic signatures during 2012 Emilia seismic sequence.

    Sciarra, Alessandra; Cantucci, Barbara; Coltorti, Massimo

    2017-10-27

    Soil surveys were performed in Medolla (Italy), a peculiar area characterized by spotty high soil temperature, gas vent, and lack of vegetation, to determine the migration mechanisms and spatial behavior of gas species. Hereby we present soil gas measurements and their isotopic ratios measured between 2008 and 2015, including the 2012 Emilia-Romagna seismic sequence. We found that soil gas concentrations markedly changed during the main shocks of May 20 and 29, 2012 (Mw 6.1 and 6.0, respectively), highlighting the presence of a buried fault intersecting the gas vents. We suggest that crustal dilation associated with seismic activity favored the uprising of geogas towards the surface. Changes in the isotopic signature highlight the contribution of two distinct sources, one deeper, thermogenic and another superficial related to organic-rich layer, whose relative contribution varied before, during and after the earthquake. We suppose an increase of microbial component likely due to the ground shaking of shallower layers linked to seismic sequence, which masks the thermogenic contribution. Although the changes we detect are specific for an alluvial plain, we deduce that analogous processes may be active elsewhere, and that soil gas geochemistry represents an useful tool to discriminate the gas migration related to seismic activity.

  8. Soil-Web: An online soil survey for California, Arizona, and Nevada

    Beaudette, D. E.; O'Geen, A. T.

    2009-10-01

    Digital soil survey products represent one of the largest and most comprehensive inventories of soils information currently available. The complex structure of these databases, intensive use of codes and scientific jargon make it difficult for non-specialists to utilize digital soil survey resources. A project was initiated to construct a web-based interface to digital soil survey products (STATSGO and SSURGO) for California, Arizona, and Nevada that would be accessible to the general public. A collection of mature, open source applications (including Mapserver, PostGIS and Apache Web Server) were used as a framework to support data storage, querying, map composition, data presentation, and contextual links to related materials. Application logic was written in the PHP language to "glue" together the many components of an online soil survey. A comprehensive website ( http://casoilresource.lawr.ucdavis.edu/map) was created to facilitate access to digital soil survey databases through several interfaces including: interactive map, Google Earth and HTTP-based application programming interface (API). Each soil polygon is linked to a map unit summary page, which includes links to soil component summary pages. The most commonly used soil properties, land interpretations and ratings are presented. Graphical and tabular summaries of soil profile information are dynamically created, and aid with rapid assessment of key soil properties. Quick links to official series descriptions (OSD) and other such information are presented. All terminology is linked back to the USDA-NRCS Soil Survey Handbook which contains extended definitions. The Google Earth interface to Soil-Web can be used to explore soils information in three dimensions. A flexible web API was implemented to allow advanced users of soils information to access our website via simple web page requests. Soil-Web has been successfully used in soil science curriculum, outreach activities, and current research projects

  9. Soil and gas and radon entry potentials for substructure surfaces

    Harrison, J.; Sextro, R.G.

    1990-01-01

    This paper reports on measurement techniques and parameters that describe the potential for areas of a building substructure to have high soil gas and radon entry rates which have been developed. Flows and pressures measured at test holes in substructure surfaces while the substructure was intentionally depressurized were used in a highly simplified electrical circuit to model the substructure/soil network. Data from four New Jersey houses indicate that the soil was a factor of two to six times more resistant to soil gas flow than substructure surfaces, concrete slab floors, including perimeter gaps, cracks, and other penetrations, were approximately five times more resistant to soil gas movement than hollow block walls, and radon entry potentials were highest for slab floors. These indices of entry potential may be useful for characterizing the relative leakiness of below-grade substructure surfaces and for determining the selection and placement of radon control systems

  10. Greenhouse Gas Emissions from Brazilian Sugarcane Soils

    Carmo, J.; Pitombo, L.; Cantarella, H.; Rosseto, R.; Andrade, C.; Martinelli, L.; Gava, G.; Vargas, V.; Sousa-Neto, E.; Zotelli, L.; Filoso, S.; Neto, A. E.

    2012-04-01

    Bioethanol from sugarcane is increasingly seen as a sustainable alternative energy source. Besides having high photosynthetic efficiency, sugarcane is a perennial tropical grass crop that can re-grow up to five or more years after being planted. Brazil is the largest producer of sugarcane in the world and management practices commonly used in the country lead to lower rates of inorganic N fertilizer application than sugarcane grown elsewhere, or in comparison to other feedstocks such as corn. Therefore, Brazilian sugarcane ethanol potentially promotes greenhouse gas savings. For that reason, several recent studies have attempted to assess emissions of greenhouse gases (GHG) during sugarcane production in the tropics. However, estimates have been mainly based on models due to a general lack of field data. In this study, we present data from in situ experiments on emission of three GHG (CO2, N2O, and CH4) in sugarcane fields in Brazil. Emissions are provided for sugarcane in different phases of the crop life cycle and under different management practices. Our results show that the use of nitrogen fertilizer in sugarcane crops resulted in an emission factor for N2O similar to those predicted by IPCC (1%), ranging from 0.59% in ratoon cane to 1.11% in plant cane. However, when vinasse was applied in addition to mineralN fertilizer, emissions of GHG increased in comparison to those from the use of mineral N fertilizer alone. Emissions increased significantly when experiments mimicked the accumulation of cane trash on the soil surface with 14 tons ha-1and 21 tons ha-1, which emission factor were 1.89% and 3.03%, respectively. This study is representative of Brazilian sugarcane systems under specific conditions for key factors affecting GHG emissions from soils. Nevertheless, the data provided will improve estimates of GHG from Brazilian sugarcane, and efforts to assess sugarcane ethanol sustainability and energy balance. Funding provided by the São Paulo Research

  11. Soil gas measurements at high permeabilities and below foundation depth

    Johner, H.U; Surbeck, H.

    2000-01-01

    We started a project of soil gas measurements beneath houses. Since the foundations of houses often lie deeper than 0.5 to 1 m - the depth where soil gas measurements are often made - the first approach was to apply the method developed previously to deeper soil layers. The radon availability index (RAI), which was defined empirically, proved to be a reliable indicator for radon problems in nearby houses. The extreme values of permeability, non-Darcy flow and scale dependence of permeability stimulated the development of a multi-probe method. A hydrological model was applied to model the soil gas transport. The soil gas measurements below foundation depth provided a wealth of new information. A good classification of soil properties could be achieved. If soil gas measurements are to be made, the low permeability layer has to be traversed. A minimum depth of 1 .5 m is suggested, profiles to below the foundation depth are preferable. There are also implications for mitigation works. A sub-slab suction system should reach the permeable layer to function well. This also holds for radon wells. If a house is located on a slope, it is most convenient to install the sub-slab suction system on the hillside, as the foundation reaches the deepest levels there

  12. Microbial activities in soil near natural gas leaks

    Adamse, A D; Hoeks, J; de Bont, J A.M.

    1971-01-01

    Gas leaks cause the death of more than half the trees that perish in the streets since natural gas has been distributed in the Netherlands. Measurements performed in pot experiments, in which a sandy soil was supplied with a constant stream of a mixture of natural gas and air, proved that gas components, such as methane (81.6%), ethane (2.7%), propane (0.37%), were oxidized. Consumption of methane and oxygen, and production of carbon dioxide could be clearly demonstrated. Oxidation of methane started after an extended lag phase during which propane and ethane were found to be consumed. Methane oxidation was demonstrated by a sharp rise of the oxygen-consumption curve, followed by a fall until it became rather constant. After the gas supply had been stopped, a long recovery period was found to be needed for restoring the normal oxygen consumption of the soil. The rate of oxidation was subject to seasonal differences in temperature. Counts of bacteria in soil were carried out using Oxiod membrane filters on Whatman paper discs soaked with a basic salts solutions according to Leadbetter and Foster (1958) or on soil-extract agar plates. Incubation temperature was 30C. The presence of natural gas in soil resulted in an adaptation of the aerobic microflora to this substrate. Moreover, it stimulated the total aerobic microflora as counted on soil-extract agar plates.

  13. The History of Electromagnetic Induction Techniques in Soil Survey

    Brevik, Eric C.; Doolittle, Jim

    2014-05-01

    Electromagnetic induction (EMI) has been used to characterize the spatial variability of soil properties since the late 1970s. Initially used to assess soil salinity, the use of EMI in soil studies has expanded to include: mapping soil types; characterizing soil water content and flow patterns; assessing variations in soil texture, compaction, organic matter content, and pH; and determining the depth to subsurface horizons, stratigraphic layers or bedrock, among other uses. In all cases the soil property being investigated must influence soil apparent electrical conductivity (ECa) either directly or indirectly for EMI techniques to be effective. An increasing number and diversity of EMI sensors have been developed in response to users' needs and the availability of allied technologies, which have greatly improved the functionality of these tools. EMI investigations provide several benefits for soil studies. The large amount of georeferenced data that can be rapidly and inexpensively collected with EMI provides more complete characterization of the spatial variations in soil properties than traditional sampling techniques. In addition, compared to traditional soil survey methods, EMI can more effectively characterize diffuse soil boundaries and identify included areas of dissimilar soils within mapped soil units, giving soil scientists greater confidence when collecting spatial soil information. EMI techniques do have limitations; results are site-specific and can vary depending on the complex interactions among multiple and variable soil properties. Despite this, EMI techniques are increasingly being used to investigate the spatial variability of soil properties at field and landscape scales.

  14. Greenhouse-gas emissions from soils increased by earthworms

    Lubbers, I.M.; Groenigen, van K.J.; Fonte, S.J.; Six, J.; Brussaard, L.; Groenigen, van J.W.

    2013-01-01

    Earthworms play an essential part in determining the greenhouse-gas balance of soils worldwide, and their influence is expected to grow over the next decades. They are thought to stimulate carbon sequestration in soil aggregates, but also to increase emissions of the main greenhouse gases carbon

  15. PAH loss during bioremediation of manufactured gas plant site soils

    Erickson, D C [and others

    1993-01-01

    Laboratory studies using soil samples from a former gas works site showed that PAH in the soil were present in a form resistant to biodegradation, whereas added naphthalene and phenanthrene were quickly degraded. The PAH already present were not extractable into water, and were not toxic to bacteria.

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

    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

  17. Soil gas geochemistry in relation to eruptive fissures on Timanfaya volcano, Lanzarote Island (Canary Islands, Spain)

    Padrón, Eleazar; Padilla, Germán; Hernández, Pedro A.; Pérez, Nemesio M.; Calvo, David; Nolasco, Dácil; Barrancos, José; Melián, Gladys V.; Dionis, Samara; Rodríguez, Fátima

    2013-01-01

    We report herein the first results of an extensive soil gas survey performed on Timanfaya volcano on May 2011. Soil gas composition at Timanfaya volcano indicates a main atmospheric source, slightly enriched in CO2 and He. Soil CO2 concentration showed a very slight deep contribution of the Timanfaya volcanic system, with no clear relation to the main eruptive fissures of the studied area. The existence of soil helium enrichments in Timanfaya indicates a shallow degassing of crustal helium and other possible deeper sources probably form cooling magma bodies at depth. The main soil helium enrichments were observed in good agreement with the main eruptive fissures of the 1730-36 eruption, with the highest values located at those areas with a higher density of recent eruptive centers, indicating an important structural control for the leakage of helium at Timanfaya volcano. Atmospheric air slightly polluted by deep-seated helium emissions, CO2 degassed from a cooling magma body, and biogenic CO2, might be the most plausible explanation for the existence of soil gas. Helium is a deep-seated gas, exhibiting important emission rates along the main eruptive fissure of the 1730-36 eruption of Timanfaya volcano.

  18. Molecular analysis of manufactured gas plant soils for naphthalene mineralization

    Sanseverino, J.; Werner, C.; Fleming, J.; Applegate, B.M.; King, J.M.H.; Sayler, G.S.; Blackburn, J.

    1991-01-01

    New molecular tools are being developed and tested to ascertain the biodegradability of hazardous wastes by soil bacterial population. The potential for manufactured gas plant (MGP) soil bacterial populations to degrade naphthalene, as a component mixture of polynuclear aromatic hydrocarbons, was evaluated by the detection of a naphthalene biodegradative genotype by DNA probe hybridization with DNA extracts and colonies of cultured bacteria of the MGP soils. The activity of the naphthalene-degrading populations was evaluated by mineralization assays, 14 CO 2 production from 14 C-naphthalene. Direct messenger RNA (mRNA) extraction from MGP soil was evaluated as an instantaneous measure of naphthalene catabolic gene expression in MGP soil. The bioavailability of naphthalene for bacterial degradation within the MGP soils was assessed by measuring the bioluminescent response of a naphthalene-lux catabolic reporter strain Pseudomonas fluorescens HK44 (pUTK21). DNA extracted from 5 MGP soils and 1 creosote-contaminated soil and hybridized with a nahA gene probe indicated that the naphthalene degradative genes were present in all samples in the range of 0.06 to 0.95 ng/100 μl DNA extract which was calculated to represent 3.58 x 10 8 to 1.05 x 10 10 nahA positive cells/g soil. Phenanthrene, anthracene, and benzo(a)pyrene were mineralized also by some of the soils. NAH7 homologous messenger RNA transcripts were detectable in one MGP soil and in the creosote-contaminated soil

  19. Delineation of ground-water contamination using soil-gas analyses near Jackson, Tennessee

    Lee, R.W.

    1991-01-01

    An investigation of the ground-water resources near Jackson, West Tennessee, was conducted during 1988-89. The study included determination of the occurrence of contaminants in the shallow aquifer using soil-gas analyses in the unsaturated zone. Between 1980 and 1988, an underground fuel-storage tank leaked about 3,000 gallons of unleaded fuel to the water table about 4 feet below land surface. A survey of soil gas using a gas chromatograph equipped with a photoionization detector showed concentrations of volatile organic compounds greater than IO, 000 parts per million near the leak These compounds were detected in an area about 240 feet long and 110 feet wide extending west from the point source. The chromatograms provided two distinct 'fingerprints' of volatile organic compounds. The first revealed the presence of benzene, toluene, andxylenes, which are constituents of unleaded fuel, in addition to other volatile compounds, in soil gas in the area near the leak The second did not reveal any detectable benzene, toluene, or xylenes in the soil-gas samples, but showed the presence of other unidentified volatile organic compounds in soil gas north of the storage tank. The distribution of total concentrations of volatile organic compounds in the unsaturated zone indicated that a second plume about 200 feet long and 90 feet wide was present about 100 feet north of the storage tank The second plume could have been the result of previous activities at this site during the 1950's or earlier. Activities at the site are believed to have included storage of solvents used at the nearby railyard and flushing of tanks containing tar onto a gravel-covered parking area. The delineation of these plumes has shown that soil-gas analyses can be a useful technique for identifying areas of contamination with volatile organic compounds in shallow water-table aquifers and may have broad applications in similar situations where the water table is relatively close to the surface.

  20. Using greenhouse gas fluxes to define soil functional types

    Petrakis, Sandra; Barba, Josep; Bond-Lamberty, Ben; Vargas, Rodrigo

    2017-12-04

    Soils provide key ecosystem services and directly control ecosystem functions; thus, there is a need to define the reference state of soil functionality. Most common functional classifications of ecosystems are vegetation-centered and neglect soil characteristics and processes. We propose Soil Functional Types (SFTs) as a conceptual approach to represent and describe the functionality of soils based on characteristics of their greenhouse gas (GHG) flux dynamics. We used automated measurements of CO2, CH4 and N2O in a forested area to define SFTs following a simple statistical framework. This study supports the hypothesis that SFTs provide additional insights on the spatial variability of soil functionality beyond information represented by commonly measured soil parameters (e.g., soil moisture, soil temperature, litter biomass). We discuss the implications of this framework at the plot-scale and the potential of this approach at larger scales. This approach is a first step to provide a framework to define SFTs, but a community effort is necessary to harmonize any global classification for soil functionality. A global application of the proposed SFT framework will only be possible if there is a community-wide effort to share data and create a global database of GHG emissions from soils.

  1. Analysis of volatile phase transport in soils using natural radon gas as a tracer

    Chen, C.; Thomas, D.M.

    1992-01-01

    We have conducted a field study of soil gas transport processes using radon gas as a naturally occurring tracer. The experiment monitored soil gas radon activity, soil moisture, and soil temperature at three depths in the shallow soil column; barometric pressure, rainfall and wind speed were monitored at the soil surface. Linear and multiple regression analysis of the data sets has shown that the gas phase radon activities under natural environmental conditions are influenced by soil moisture content, barometric pressure variations, soil temperature and soil structure. The effect of wind speed on subsurface radon activities under our field conditions has not been demonstrated

  2. Fracture mapping in clays, using gas geochemistry: background, design of a mobile laboratory, and surveys in England and Italy

    Gregory, R.G.; Duddridge, G.A.

    1991-01-01

    Integrated soil gas analyses for helium, radon, carbon dioxide and oxygen allow the accurate interpretation of soil gas signatures as indicators of underlying structure, due to large variations over faults and fractures. Structures such as these provide channelways for fluid movement in the upper crust. A mobile gas geochemistry laboratory for the analysis of soil gases was constructed and surveys were carried out at sites in England and Italy. At the Down Ampney site, Gloucestershire, gas was injected into a fault plane, and recorded some hours later at the surface. Refinement of this experiment would allow a full characterization of permeable pathways at a site to be made. The soil gas technique has been shown to be viable as an independent site investigation method for the study of fracturing and groundwater movement around potential waste repository sites

  3. Fracture mapping in clays: using gas geochemistry. Background, design of a mobile laboratory and surveys in England and Italy

    Duddridge, G.A.

    1991-06-01

    Integrated soil gas analyses for helium, radon, carbon dioxide and oxygen allow the accurate interpretation of soil gas signatures as indicators of underlying structure, due to large variations over faults and fractures. Structures such as these provide channelways for fluid movement in the upper crust. A mobile gas geochemistry laboratory for the analysis of soil gases was constructed and surveys were carried out at sites in England and Italy. At the Down Ampney site, Gloucestershire, gas was injected into a fault plane, and recorded some hours later at the surface. Refinement of this experiment would allow a full characterisation of permeable pathways at a site to be made. The soil gas technique has been shown to be viable as an independent site investigation method for the study of fracturing and groundwater movement around potential waste repository sites. (author)

  4. Carbon tetrachloride ERA soil-gas baseline monitoring

    Fancher, J.D.

    1994-01-01

    From December 1991 through December 1993, Westinghouse Hanford Company performed routine baseline monitoring of selected wells ad soil-gas points twice weekly in the 200 West Area of the Hanford Site. This work supported the carbon Tetrachloride Expedited Response Action (ERA) and provided a solid baseline of volatile organic compound (VOC) concentrations in wells and in the subsurface at the ERA site. As site remediation continues, comparisons to this baseline can be one means of measuring the success of carbon tetrachloride vapor extraction. This report contains observations of the patterns and trends associated with data obtained during soil-gas monitoring at the 200 West Area: Monitoring performed since late 1991 includes monitoring soil-gas probes ad wellheads for volatile organic compounds (VOCs). This report reflects monitoring data collected from December 1991 through December 1993

  5. LEAK AND GAS PERMEABILITY TESTING DURING SOIL-GAS SAMPLING AT HAL'S CHEVRON LUST SITE IN GREEN RIVER, UTAH

    The results of gas permeability and leak testing during active soil-gas sampling at Hal’s Chevron LUST Site in Green River, Utah are presented. This study was conducted to support development of a passive soil-gas sampling method. Gas mixtures containing helium and methane were...

  6. Entry of soil gas and radon into houses

    Andersen, C.E.

    1992-04-01

    Entry of soil gas and radon into houses has been investigated by experiments conducted at radon test structures and numerical or analytical modelling. The numerical model solves the steady-state equations for Darcy flow of soil-gas and combined diffusive and advective transport of radon. Model calculations were compared with results from field experiments conducted at Risoe National Laboratory, and it was found that there was good agreement between measured and modelled pressure coupling and radon concentration profiles. Discrepancies regarding absolute values of soil-gas entry rates and radon concentrations were observed. The numerical model has been used to study the importance of soil and building related factors on radon entry rates into slab-on-grade houses. It was found that, for a house with a 3 mm perimeter crack along the floor-wall joint, the entry was mainly determined by the soil permeability and building related factors such as house depressurization and presence of a capillary breaking layer of gravel below the slab. In a house with a bare soil floor, the diffusivity of the soil was found to be of principal importance for the entry rate even for moderate permeabilities. An analytical model was developed for the purpose of studying soil-gas entry rates into houses in response to non-static driving forces. It is based on the analogy between a 'buried drain' and a basement house with a perimeter crack. The structure was depressurized sinusoidally in time and the frequency dependent pressure couplings were measured. There was fairly good agreement between theoretical and experimental results. (LN) (26 tabs., 30 ills., 66 refs.)

  7. Radon gas sampler for indoor and soil measurements and its applications

    Azimi-Garakani, D.; Flores, B.; Piermattei, S.; Susanna, A.F.; Seidel, J.L.; Tommasino, L.; Torri, G.

    1988-01-01

    A national large scale survey of indoor radon (based on an optimised sampling strategy) is needed in Italy to obtain average population dose for use in epidemiological studies. Since in the great majority of cases, one of the most important radon sources is the soil and rock beneath the houses, it would be interesting to combine this survey with measurements of bed-soil radon. With these objectives in mind, a new radon monitor device has been developed consisting of two etched track detectors enclosed in a heat-sealed polyethylene bag. When compared with existing techniques, this radon gas sampler presents several advantages for both indoor and outdoor measurements. As a pilot project, radon gas measurements have been carried out in hundreds of different sites and for several locations; measurements have been made for different years. Typical houses with relatively high radon concentrations have also been thoroughly investigated. (author)

  8. Mississippi exploration field trials using microbial, radiometrics, free soil gas, and other techniques

    Moody, J.S.; Brown, L.R.; Thieling, S.C.

    1995-12-31

    The Mississippi Office of Geology has conducted field trials using the surface exploration techniques of geomicrobial, radiometrics, and free soil gas. The objective of these trials is to determine if Mississippi oil and gas fields have surface hydrocarbon expression resulting from vertical microseepage migration. Six fields have been surveyed ranging in depth from 3,330 ft to 18,500 ft. The fields differ in trapping styles and hydrocarbon type. The results so far indicate that these fields do have a surface expression and that geomicrobial analysis as well as radiometrics and free soil gas can detect hydrocarbon microseepage from pressurized reservoirs. All three exploration techniques located the reservoirs independent of depth, hydrocarbon type, or trapping style.

  9. Soil survey - a basis for european soil protection

    Hodgson, J.M.

    1991-01-01

    The information available on soils varies greatly from country to country. In view of the fact that, together with water, soils represent the most important natural resource in the EC, it is recommended that steps should be taken to ensure a reasonable level of information for all countries and that emphasis be placed on assembling an adequate database. Such information is fundamental to future land use and environmental protection

  10. Survey of landfill gas generation potential

    Gauntlett, W.D.

    1992-09-01

    This project identifies all the landfill sites in each of the 50 states capable of producing 750,000 SCFD of mixed landfill gas for a period of at least 10 years. The study identified 749 landfill sites nationally, with an aggregate gas production rate sufficient to fuel approximately 6000 MW of fuel cell power plants

  11. Assessment of soil-gas, soil, and water contamination at the former hospital landfill, Fort Gordon, Georgia, 2009-2010

    Falls, Fred W.; Caldwell, Andral W.; Guimaraes, Wladmir B.; Ratliff, W. Hagan; Wellborn, John B.; Landmeyer, James E.

    2011-01-01

    Soil gas, soil, and water were assessed for organic and inorganic constituents at the former hospital landfill located in a 75-acre study area near the Dwight D. Eisenhower Army Medical Center, Fort Gordon, Georgia, from April to September 2010. Passive soil-gas samplers were analyzed to evaluate organic constituents in the hyporheic zone of a creek adjacent to the landfill and soil gas within the estimated boundaries of the former landfill. Soil and water samples were analyzed to evaluate inorganic constituents in soil samples, and organic and inorganic constituents in the surface water of a creek adjacent to the landfill, respectively. This assessment was conducted to provide environmental constituent data to Fort Gordon pursuant to requirements of the Resource Conservation and Recovery Act Part B Hazardous Waste Permit process. Results from the hyporheic-zone assessment in the unnamed tributary adjacent to the study area indicated that total petroleum hydrocarbons and octane were the most frequently detected organic compounds in groundwater beneath the creek bed. The highest concentrations for these compounds were detected in the upstream samplers of the hyporheic-zone study area. The effort to delineate landfill activity in the study area focused on the western 14 acres of the 75-acre study area where the hyporheic-zone study identified the highest concentrations of organic compounds. This also is the part of the study area where a debris field also was identified in the southern part of the 14 acres. The southern part of this 14-acre study area, including the debris field, is steeper and not as heavily wooded, compared to the central and northern parts. Fifty-two soil-gas samplers were used for the July 2010 soil-gas survey in the 14-acre study area and mostly detected total petroleum hydrocarbons, and gasoline and diesel compounds. The highest soil-gas masses for total petroleum hydrocarbons, diesel compounds, and the only valid detection of perchloroethene

  12. Analytical characterization of contaminated soils from former manufactured gas plants

    Haeseler, F.; Blanchet, D.; Vandecasteele, J.P.; Druelle, V.; Werner, P.; Technische Univ., Dresden,

    1999-01-01

    Detailed analytical characterization of the organic matter (OM) of aged polluted soils from five former manufactured gas plants (MGP) and of two coal tars was completed. It was aimed at obtaining information relevant to the physicochemical state of the polycyclic aromatic hydrocarbon (PAH) pollutants and to their in-situ evolution in time. Overall characterization of total OM (essentially polluting OM) was carried out directly on soil samples with or without prior extraction with solvent. It involved a technique of pyrolysis/oxidation coupled to flame ionization/thermal conductivity detection. Extracts in solvent were fractionated by liquid chromatography into saturated hydrocarbons, PAH, and resins, the first two fractions being further characterized by gas chromatography and mass spectrometry. The compositions of OM of soils were found to be very similar. A total of 28% of organic carbon, including all PAH, was extractable by solvent. The compositions of coal tars were qualitatively similar to those of OM of MGP soils but with a higher proportion (48%) of total extractable OM and of PAH, in particular lower PAH. Contamination of MGP soils appeared essentially as coal tar having undergone natural attenuation. The constant association of PAH with heavy OM in MGP soils is important with respect to the mobility and bioaccessibility of these pollutants

  13. Coastal vegetation invasion increases greenhouse gas emission from wetland soils but also increases soil carbon accumulation

    Chen, Yaping; Chen, Guangcheng; Ye, Yong

    2015-01-01

    Soil properties and soil–atmosphere fluxes of CO 2 , CH 4 and N 2 O from four coastal wetlands were studied throughout the year, namely, native Kandelia obovata mangrove forest vs. exotic Sonneratia apetala mangrove forest, and native Cyperus malaccensis salt marsh vs. exotic Spartina alterniflora salt marsh. Soils of the four wetlands were all net sources of greenhouse gases while Sonneratia forest contributed the most with a total soil–atmosphere CO 2 -equivalent flux of 137.27 mg CO 2 m −2 h −1 , which is 69.23%, 99.75% and 44.56% higher than that of Kandelia, Cyperus and Spartina, respectively. The high underground biomass and distinctive root structure of Sonneratia might be responsible for its high greenhouse gas emission from the soil. Soils in Spartina marsh emitted the second largest amount of total greenhouse gases but it ranked first in emitting trace greenhouse gases. Annual average CH 4 and N 2 O fluxes from Spartina soil were 13.77 and 1.14 μmol m −2 h −1 , respectively, which are 2.08 and 1.46 times that of Kandelia, 1.03 and 1.15 times of Sonneratia, and 1.74 and 1.02 times of Cyperus, respectively. Spartina has longer growing season and higher productivity than native marshes which might increase greenhouse gas emission in cold seasons. Exotic wetland soils had higher carbon stock as compared to their respective native counterparts but their carbon stocks were offset by a larger proportion because of their higher greenhouse gas emissions. Annual total soil–atmosphere fluxes of greenhouse gases reduced soil carbon burial benefits by 8.1%, 9.5%, 6.4% and 7.2% for Kandelia, Sonneratia, Cyperus and Spartina, respectively, which narrowed down the gaps in net soil carbon stock between native and exotic wetlands. The results indicated that the invasion of exotic wetland plants might convert local coastal soils into a considerable atmospheric source of greenhouse gases although they at the same time increase soil carbon accumulation

  14. Coastal vegetation invasion increases greenhouse gas emission from wetland soils but also increases soil carbon accumulation

    Chen, Yaping [Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, College of the Environment and Ecology, Xiamen University, Xiamen 361102, Fujian (China); Chen, Guangcheng [Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, Fujian (China); Ye, Yong, E-mail: yeyong.xmu@gmail.com [Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, College of the Environment and Ecology, Xiamen University, Xiamen 361102, Fujian (China)

    2015-09-01

    Soil properties and soil–atmosphere fluxes of CO{sub 2}, CH{sub 4} and N{sub 2}O from four coastal wetlands were studied throughout the year, namely, native Kandelia obovata mangrove forest vs. exotic Sonneratia apetala mangrove forest, and native Cyperus malaccensis salt marsh vs. exotic Spartina alterniflora salt marsh. Soils of the four wetlands were all net sources of greenhouse gases while Sonneratia forest contributed the most with a total soil–atmosphere CO{sub 2}-equivalent flux of 137.27 mg CO{sub 2} m{sup −2} h{sup −1}, which is 69.23%, 99.75% and 44.56% higher than that of Kandelia, Cyperus and Spartina, respectively. The high underground biomass and distinctive root structure of Sonneratia might be responsible for its high greenhouse gas emission from the soil. Soils in Spartina marsh emitted the second largest amount of total greenhouse gases but it ranked first in emitting trace greenhouse gases. Annual average CH{sub 4} and N{sub 2}O fluxes from Spartina soil were 13.77 and 1.14 μmol m{sup −2} h{sup −1}, respectively, which are 2.08 and 1.46 times that of Kandelia, 1.03 and 1.15 times of Sonneratia, and 1.74 and 1.02 times of Cyperus, respectively. Spartina has longer growing season and higher productivity than native marshes which might increase greenhouse gas emission in cold seasons. Exotic wetland soils had higher carbon stock as compared to their respective native counterparts but their carbon stocks were offset by a larger proportion because of their higher greenhouse gas emissions. Annual total soil–atmosphere fluxes of greenhouse gases reduced soil carbon burial benefits by 8.1%, 9.5%, 6.4% and 7.2% for Kandelia, Sonneratia, Cyperus and Spartina, respectively, which narrowed down the gaps in net soil carbon stock between native and exotic wetlands. The results indicated that the invasion of exotic wetland plants might convert local coastal soils into a considerable atmospheric source of greenhouse gases although they at the

  15. Soil Survey Geographic (SSURGO) database for Mora County Area, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  16. Soil Survey Geographic (SSURGO) database for Chaves County, New Mexico, Northern Part

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  17. Soil Survey Geographic (SSURGO) database for Mescalero-Apache Area, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  18. Soil Survey Geographic (SSURGO) database for Lincoln County Area, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  19. Soil Survey Geographic (SSURGO) database for Cabezon Area, New Mexico (Sandoval County, New Mexico)

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  20. Soil Survey Geographic (SSURGO) database for Catron County, New Mexico, Northern Part

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  1. Soil Survey Geographic (SSURGO) database for Chaves County, New Mexico, Southern Part

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  2. Soil Survey Geographic (SSURGO) database for San Miguel County Area, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  3. Soil Survey Geographic (SSURGO) database for Grant County, Central and Southern Parts, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  4. Soil Survey Geographic (SSURGO) database for Sierra County Area, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  5. Soil Survey Geographic (SSURGO) database for Santa Fe County, Area New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  6. Soil Survey Geographic (SSURGO) database for Fort Bliss Military Reservation, New Mexico and Texas

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  7. Soil Survey Geographic (SSURGO) database for Socorro County Area, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  8. Soil Survey Geographic (SSURGO) database for Tucumcari Area, Northern Quay County, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  9. Soil Survey Geographic (SSURGO) database for Carson National Forest, New Mexico, Part of Rio Arriba County

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  10. Soil Survey Geographic (SSURGO) database for White Sands National Monument, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  11. Soil Survey Geographic (SSURGO) database for McKinley County Area, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  12. Soil Survey Geographic (SSURGO) database for Dona Ana County Area, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  13. Soil Survey Geographic (SSURGO) database for De Baca County Area, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  14. Soil Survey Geographic (SSURGO) database for San Juan County, New Mexico, Eastern Part

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  15. Soil Survey Geographic (SSURGO) database for Ute Mountain Area, Colorado and New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  16. Soil Survey Geographic (SSURGO) database for Valencia County, New Mexico, Eastern Part

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  17. Survey Method for Radiological Surveys of 300-FF-1 Operable Unit Soils and Material

    Brehm, D.M.

    1998-06-01

    This technical basis is to be used to survey soils at the 300-FF-1 Operable Unit during remediation of the site. Its purpose is to provide a basis for the survey methods to be employed by radiological control technician (RCTs) to guide the excavation effort in accordance with the 300-FF-1 waste site Record of Decision (ROD). The ROD for the 300-FF-1 Operable Unit requires selective excavation, removal, and disposal of contaminated soil above 350 pCi/g total uranium activity. Soil above this level will be disposed of as radioactive waste. The remaining soil will remain onsite

  18. Livermore Big Trees Park Soil Survey

    McConachie, W.A.; Failor, R.A.

    1995-01-01

    Lawrence Livermore National Laboratory (LLNL) will sample and analyze soil in the Big Trees Park area in Livermore, California, to determine if the initial level of plutonium (Pu) in a soil sample taken by the U.S. Environmental Protection Agency (EPA) in September 1993 can be confirmed. Nineteen samples will be collected and analyzed: 4 in the area where the initial EPA sample was taken, 2 in the nearby Arroyo Seco, 12 in scattered uncovered soil areas in the park and nearby school, and 1 from the sandbox of a nearby apartment complex. Two quality control (QC) samples (field duplicates of the preceding samples) win also be collected and analyzed. This document briefly describes the purpose behind the sampling, the sampling rationale, and the methodology

  19. Soil survey of Solid Waste Storage Area 6

    Lietzke, D.A.; Lee, S.Y.

    1986-06-01

    An intensive soil survey was made of Solid Waste Storage Area (SWSA) 6 (Oak Ridge National Laboratory) at a scale of 1:1200. The amount of chemical weathering, the thickness of upland soils, and the depth to unoxidized rock are dependent on slope gradient, water-flow pathways, degree of rock fracturing, and the extent of soil and rock erosion by late Pleistocene and Holocene geomorphic processes. Foot-slope landforms have generally concave slope shapes where sediment accumulates. Colluvium stratigraphy exhibits at least one lithologic discontinuity, but there may be two discontinuities preserved in some thicker colluvia. One or more paleosols, either complete or partially truncated, are preserved in these concave landforms. Alluvial soils were not examined in detail but were separated from colluvial soils because of their wetness. A small area of ancient alluvium was located on a stable upland summit that formed the highest elevation in SWSA-6. On the nearly level summit, a thin loess cap was preserved on the older alluvial soil. Upland and colluvial soils are all highly leached and strongly acid even though they are formed from a calcareous parent rock. The highly fractured rock, being relatively permeable, has been leached free of carbonates in the upper levels so that there is a wide pH gradient from the surface downward. Most of the soils were classified as Ultisols, with minimal areas of Alfisols, Inceptisols, and Entisols. Based on the soil survey, representative landforms and soils will be selected to study physical, chemical, and mineralogical properties of the soil and weathered rock. Those properties will be used to predict both the amount and duration of leachate filtration and purification in downward migration to the water table or lateral migration through colluvial and alluvial soils to ground-water seeps

  20. Soil-gas radon as seismotectonic indicator in Garhwal Himalaya

    Ramola, R.C.; Prasad, Yogesh; Prasad, Ganesh; Kumar, Sushil; Choubey, V.M.

    2008-01-01

    Research on earthquake-related radon monitoring has received enormous attention recently. Anomalous behaviour of radon in soil and groundwater can be used as a reliable precursor for an impending earthquake. While earthquake prediction may not yet be possible, earthquake prediction research has greatly increased our understanding of earthquake source mechanisms, the structural complexities of fault zones, and the earthquake recurrence interval, expected at a given location. This paper presents some results of continuous monitoring of radon in soil-gas in Garhwal Himalaya, India. Daily soil-gas radon monitoring with seismic activity and meteorological parameters were performed in the same laboratory system, located at H.N.B. Garhwal University Campus, Tehri Garhwal, India. Radon anomalies along with meteorological parameters were found to be statistically significant for the seismic events within the magnitudes M2.0-M6.0 and epicentral distances of 16-250 km from the monitoring station. The frequent positive and negative anomalies with constant environmental perturbation indicate the opening and closing of micro cracks within the volume of dilatancy by strain energy. The spike-like and sharp peak anomalies were recorded before, during and after earthquakes occurred in the area. The variations in radon concentrations in soil-gas are found to be correlated with seismic activities in the Garhwal Himalaya. The correlation between radon level and meteorological parameters is also discussed

  1. Separate effects of flooding and anaerobiosis on soil greenhouse gas emissions and redox sensitive biogeochemistry

    Gavin McNicol; Whendee L. Silver

    2014-01-01

    Soils are large sources of atmospheric greenhouse gases, and both the magnitude and composition of soil gas emissions are strongly controlled by redox conditions. Though the effect of redox dynamics on greenhouse gas emissions has been well studied in flooded soils, less research has focused on redox dynamics without total soil inundation. For the latter, all that is...

  2. Alternate data sources for soil surveys on rangeland

    Horvath, Emil H.; Klingebiel, A.A.; Moore, D.G.; Fosnight, E.A.

    1983-01-01

    Soil information is an essential theme in a digital information base for land management and resource monitoring, but public land management agencies seldom have detailed soil maps available for all of the area under their administration. Most of these agencies conduct soil surveys on a scheduled basis, but escalating costs and declining budgets are reducing the number of surveys that can be scheduled. Digital elevation and satellite spectral data are available or are obtainable for all areas in the continental United States and may be used as an aid to produce soils data. A study was conducted in the Grass Creek Resource Area in north-central Wyoming to assess the utility of incorporating digital elevation and Landsat data into an information base for soil survey and to evaluate the usefulness of these data as an input to an order-three soil survey. Slope-interval maps were produced from digital elevation data and topographic maps of three 7.5-minute quadrangle areas. These slope-interval maps were then overlaid on orthophotoquadrangles and used to produce photo-interpreted physiographic maps. These physiographic maps were digitized into a data base and used with Landsat multispectral scanner data to produce tabular summaries that describe each map polygon in terms of physiographic unit, slope, aspect, elevation, area, and spectral values. A good

  3. Use of LANDSAT imagery for soil survey

    Dejesusparada, N. (Principal Investigator); Filho, M. V.; Higa, N. T.; Celsodecarvalho, V.

    1977-01-01

    The author has identified the following significant results. The MSS channels 6 and 7 were considered the best to study the relative tonality of different spectral responses of soils, while channels 5 and 7 were best for natural vegetation, drainage patterns, and land use. Frequency ratio was the recommended index for use when analyzing a drainage pattern quantitatively.

  4. Effect of biochar on soil structural characteristics: water retention and gas transport

    Sun, Zhencai; Møldrup, Per; Vendelboe, Anders Lindblad

    Biochar addition to agricultural soil has been reported to reduce climate gas emission, as well as improve soil fertility and crop productivity. Little, however, is known about biochar effects on soil structural characteristics. This study investigates if biochar-application changes soil structural...... characteristics, as indicated from water retention and gas transport measurements on intact soil samples. Soil was sampled from a field experiment on a sandy loam with four control plots (C) without biochar and four plots (B) with incorporated biochar at a rate of 20 tons per hectare (plot size, 6 x 8 m). The C......-gas diffusivity on intact 100cm3 soil samples (5 replicates in each plot). We found that biochar application significantly decreased soil bulk density, hereby creating higher porosity. At the same soil-water matric potential, all the soil-gas phase parameters (air-filled porosity, air permeability and gas...

  5. Canadian oil and gas survey : 1997

    Roberge, R.B.

    1997-01-01

    An outlook of the Canadian Petroleum Industry, financial and operating statistics of the top 100 Canadian public oil and gas companies and 15 energy income trusts, were summarized for the fiscal year ending in 1996. In general, 1996 was a good year for the industry. Greater industry financing resulted in increased drilling activity and good stock market returns for investors. However, strong commodity prices also resulted in record levels of hedging activity, which meant lost revenues for the industry. The top 100 companies recorded losses of about $800 million in 1996, largely on crude oil hedges. The fact that volumes hedged forward to 1997 are down from 1996 indicate that many companies are rethinking their commitment to risk management. Details of crude oil and natural gas prices and production levels during 1996 were provided. A list of significant corporate mergers and acquisitions during the year under review rounded out the presentation

  6. Microbial activities in soil near natural gas leaks

    Adamse, A D; Hoeks, J; de Bont, J A.M.; van Kessel, J F

    1972-01-01

    From the present experiments it may be concluded that in the surroundings of natural gas leaks, methane, ethane and possibly some other components of the natural gas are oxidized by microbial activities as long as oxygen is available. This is demonstrated by an increased oxygen consumption and carbon dioxide production, as well as by increased numbers of different types of bacteria. The resulting deficiency of oxygen, the excess of carbon dioxide, and perhaps the formation of inhibitory amounts of ethylene, are considered to be mainly responsible for the death of trees near natural gas leaks. Also the long period of time needed by the soil to recover, may be due to prolonged microbial activities, as well as to the presence of e.g. ethylene. The present experiments suggest that especially methane-oxidizing bacteria of the Methylosinus trichosporium type were present in predominating numbers and consequently have mainly been responsible for the increased oxygen consumption. However, some fungi oxidizing components of natural gas, including methane and ethane may also have contributed to the increased microbial activities in the soil. The same will be true of a possible secondary microflora on products derived from microorganisms oxidizing natural gas components. 12 references, 9 figures, 7 tables.

  7. Soil gas radon and thoron measurements in some Venezuelan oilfields

    Fernandez, Daniel Palacios; Yininber Avila; Teixeira, Diana; Sajo-Bohus, Laszlo; Greaves, Eduardo; Barros, Haydn; Fusella, Emidio; Salas, Johnny; Fernandez, Guillermo; Bolivar, Manuel; Regalado, Jimmy

    2016-01-01

    Radon and thoron concentrations in soil gas were studied in some Venezuelan oilfields using passive and active methods. In some cases, investigations indicated a strong correlation between oil production areas and the intensity of radon signals, while in others a decrease in radon concentration was observed. This behavior was explained on the basis of different geological structures of the associated reservoir traps. Geological faults associated with petroleum systems were well recognized by the radon and thoron anomalies. Possible conduits and sources responsible for the occurrence of natural gas in a river and in an aquifer were identified and localized. (author)

  8. HTO deposition through gas exchange between soil and atmosphere

    Feinhals, J.

    1988-06-01

    Theoretical considerations show that the ratio of HTO/H 2 O molecules, i.e. the specific activity, is not the same in atmospheric humidity and moisture absorption but differs by the so-called specific activity coefficient k. On this basis a computer model (ATHOS) was developed which allowed the calculation of both the surface contamination of the soil due to the gas exchange with a contaminated atmosphere and the depth-specific distribution of the soil acitvity. On the one hand the equations base on a modified Philip-de Vries theory, and on the other hand on a large number of soil column experiments which served the examination of the influence of parameters of microclimate and soil physics on the absorption and diffusion of tritiated water vapour under simulated conditions Above all the individual capability of each soil type to absorb moisture must be taken into consideration in connection with the HTO transfer. In this context theoretical and experimental examinations were carried out indicating a practice-related possibility to determine the soil-specific absorption capability. (orig./DG) [de

  9. National Gas Survey. Synthesized gaseous hydrocarbon fuels

    None

    1978-06-01

    The supply-Technical Advisory Task Force-Synthesized Gaseous Hydrocarbon Fuels considered coal, hydrocarbon liquids, oil shales, tar sands, and bioconvertible materials as potential feedstocks for gaseous fuels. Current status of process technology for each feedstock was reviewed, economic evaluations including sensitivity analysis were made, and constraints for establishment of a synthesized gaseous hydrocarbon fuels industry considered. Process technology is presently available to manufacture gaseous hydrocarbon fuels from each of the feedstocks. In 1975 there were eleven liquid feedstock SNG plants in the United States having a capacity of 1.1 billion SCFD. There can be no contribution of SNG before 1982 from plants using feedstocks other than liquids because there are no plants in operation or under construction as of 1977. Costs for SNG are higher than current regulated prices for U.S. natural gas. Because of large reserves, coal is a prime feedstock candidate although there are major constraints in the area of coal leases, mining and water permits, and others. Commercial technology is available and several new gasification processes are under development. Oil shale is also a feedstock in large supply and commercial process technology is available. There are siting and permit constraints, and water availability may limit the ultimate size of an oil shale processing industry. Under projected conditions, bioconvertible materials are not expected to support the production of large quantities of pipeline quality gas during the next decade. Production of low or medium Btu gas from municipal solid wastes can be expected to be developed in urban areas in conjunction with savings in disposal costs. In the economic evaluations presented, the most significant factor for liquid feedstock plants is the anticipated cost of feedstock and fuel. The economic viability of plants using other feedstocks is primarily dependent upon capital requirements.

  10. Soil Carbon Chemistry and Greenhouse Gas Production in Global Peatlands

    Normand, A. E.; Turner, B. L.; Lamit, L. J.; Smith, A. N.; Baiser, B.; Clark, M. W.; Hazlett, C.; Lilleskov, E.; Long, J.; Grover, S.; Reddy, K. R.

    2017-12-01

    Peatlands play a critical role in the global carbon cycle because they contain approximately 30% of the 1500 Pg of carbon stored in soils worldwide. However, the stability of these vast stores of carbon is under threat from climate and land-use change, with important consequences for global climate. Ecosystem models predict the impact of peatland perturbation on carbon fluxes based on total soil carbon pools, but responses could vary markedly depending on the chemical composition of soil organic matter. Here we combine experimental and observational studies to quantify the chemical nature and response to perturbation of soil organic matter in peatlands worldwide. We quantified carbon functional groups in a global sample of 125 freshwater peatlands using solid-state 13C nuclear magnetic resonance (NMR) spectroscopy to determine the drivers of molecular composition of soil organic matter. We then incubated a representative subset of the soils under aerobic and anaerobic conditions to determine how organic matter composition influences carbon dioxide (CO2) and methane (CH4) emissions following drainage or flooding. The functional chemistry of peat varied markedly at large and small spatial scales, due to long-term land use change, mean annual temperature, nutrient status, and vegetation, but not pH. Despite this variation, we found predictable responses of greenhouse gas production following drainage based on soil carbon chemistry, defined by a novel Global Peat Stability Index, with greater CO2 and CH4 fluxes from soils enriched in oxygen-containing organic carbon (O-alkyl C) and depleted in aromatic and hydrophobic compounds. Incorporation of the Global Peat Stability Index of peatland organic matter into earth system models and management strategies, which will improve estimates of GHG fluxes from peatlands and ultimately advance management to reduce carbon loss from these sensitive ecosystems.

  11. An in situ method for real-time monitoring of soil gas diffusivity

    Laemmel, Thomas; Maier, Martin; Schack-Kirchner, Helmer; Lang, Friederike

    2016-04-01

    Soil aeration is an important factor for the biogeochemistry of soils. Generally, gas exchange between soil and atmosphere is assumed to be governed by molecular diffusion and by this way fluxes can be calculated using by Fick's Law. The soil gas diffusion coefficient DS represents the proportional factor between the gas flux and the gas concentration gradient in the soil and reflects the ability of the soil to "transport passively" gas through the soil. One common way to determine DS is taking core samples in the field and measuring DS in the lab. Unfortunately this method is destructive and laborious and it can only reflect a small fraction of the whole soil. As a consequence, uncertainty about the resulting effective diffusivity on the profile scale, i.e. the real aeration status remains. We developed a method to measure and monitor DS in situ. The set-up consists of a custom made gas sampling device, the continuous injection of an inert tracer gas and inverse gas transport modelling in the soil. The gas sampling device has seven sampling depths (from 0 to -43 cm of depth) and can be easily installed into vertical holes drilled by an auger, which allows for fast installation of the system. Helium (He) as inert tracer gas was injected continuously at the lower end of the device. The resulting steady state distribution of He was used to deduce the DS depth distribution of the soil. For Finite Element Modeling of the gas-sampling-device/soil system the program COMSOL was used. We tested our new method both in the lab and in a field study and compared the results with a reference lab method using soil cores. DS profiles obtained by our in-situ method were consistent with DS profiles determined based on soil core analyses. Soil gas profiles could be measured with a temporal resolution of 30 minutes. During the field study, there was an important rain event and we could monitor the decrease in soil gas diffusivity in the top soil due to water infiltration. The effect

  12. THE POTENTIAL OF γ-RAY SPECTROSCOPY FOR SOIL PROXIMAL SURVEY IN CLAYEY SOILS

    Simone Priori

    2014-01-01

    Full Text Available Gamma-ray spectroscopy surveys the intensity and distribution of γ-rays emitted from radionuclides of soils and bedrocks. The most important radionuclides of soils and rocks are: 40K, 232Th, 238U and 137Cs, the latter due to Chernobyl burst or radioactive pollution. Distribution and quantity of these radionuclides into the soil is strictly linked to parent material mineralogy and soil cation exchange capacity. The aim of this work is to show the makings of γ-ray spectroscopy proximal survey within experimental fields with clayey soils in western Sicily.The γ-ray spectrometer used for the fieldwork was “The Mole”, made by “The Soil Company”, “Medusa system” and the University of Groningen, from The Netherlands. During the survey of eight experimental fields, 55 soil samples were collected for laboratory analysis of particle size distribution, calcium carbonate, organic carbon and total nitrogen content. The results of the work showed the statistical correlations between soil features and γ-ray data. 

  13. Soil greenhouse gas emissions from afforested organic soil croplands and cutaway peatlands

    Maekiranta, P.; Hytoenen, J.; Aro, L.

    2007-01-01

    The effects of land-use and land-use change on soil greenhouse gas (GHG) fluxes are of concern due to Kyoto Protocol requirements. To quantify the soil GHG-fluxes of afforested organic soils in Finland, chamber measurements of soil CO 2 , CH 4 and N 2 O fluxes were made during the years 2002 to 2005 on twelve organic soil cropland and six cutaway peatland sites afforested 9 to 35 years ago. The annual soil CO 2 effluxes were statistically modelled using soil temperature as the driving variable and the annual CH 4 and N 2 O fluxes were estimated using the average fluxes during the measurement period. Soil CO 2 effluxes on afforested organic soil croplands varied from 207 to 539 g CO 2 -C m -2 a -1 and on cutaway peatlands from 276 to 479 g CO 2 -C m -2 a -1 . Both the afforested organic soil cropland and cutaway peatland sites acted mainly as small sinks for CH 4 ; the annual flux ranged from -0.32 to 0.61 g CH 4 -C m -2 . Afforested organic croplands emitted more N 2 O (from 0.1 to over 3.0 g N 2 O-N m -2 a -1 ) than cutaway peatland sites (from 0.01 to 0.48 g N 2 O-N m -2 a -1 ). Due to the decrease in soil CO 2 efflux, and no change in CH 4 and N 2 O fluxes, afforestation of organic croplands appears to decrease the greenhouse impact of these lands. (orig.)

  14. Survey of pumps for tritium gas

    Dowell, T.M.

    1983-05-01

    This report considers many different types of pumps for their possible use in pumping tritium gas in the low, intermediate and high vacuum ranges. No one type of pump is suitable for use over the wide range of pumping pressure required in a typical pumping system. The favoured components for such a system are: bellows pump (low vacuum); orbiting scroll pump (intermediate vacuum); magnetically suspended turbomolecular pump (high vacuum); cryopump (high vacuum). Other pumps which should be considered for possible future development are: mound modified vane pump; SRTI wobble pump; roots pump with canned motor. It is proposed that a study be made of a future tritium pumping system in a Canadian tritium facility, e.g. a tritium laboratory

  15. Survey method for radiological surveys of 300 FF-1 Operable Unit soil and materials

    Greif, A.A.

    1997-06-01

    This technical basis document is to be used to survey soils at the 300-FF-1 Operable Unit during remediation of the site. Its purpose is to provide a basis for the survey methods to be employed by the Radiological Control Technician to determine if excavated areas require continued remediation in accordance with the Record of Decision for the operable unit

  16. 222Rn and CO2 soil-gas geochemical characterization of thermally altered clays at Orciatico (Tuscany, Central Italy)

    Voltattorni, N.; Lombardi, S.; Rizzo, S.

    2010-01-01

    Research highlights: → Soil-gas technique is applied to study gas permeability of Orciatico clay units. → Clay permeability depends on thermal and mechanical alteration degree. → Soil-gas distributions are due to shallow fracturing of clays. → Rn and CO 2 soil-gas anomalies highlight secondary permeability in clay sequence. → Soil-gas results are supported by detailed geoelectrical surveys. - Abstract: The physical properties of clay allow argillaceous formations to be considered geological barriers to radionuclide migration in high-level radioactive-waste isolation systems. As laboratory simulations are short term and numerical models always involve assumptions and simplifications of the natural system, natural analogues are extremely attractive surrogates for the study of long-term isolation. The clays of the Orciatico area (Tuscany, Central Italy), which were thermally altered via the intrusion of an alkali-trachyte laccolith, represent an interesting natural model of a heat source which acted on argillaceous materials. The study of this natural analogue was performed through detailed geoelectrical and soil-gas surveys to define both the geometry of the intrusive body and the gas permeability of a clay unit characterized by different degrees of thermal alteration. The results of this study show that gas permeability is increased in the clay sequences subjected to greater heat input from the emplacement of the Orciatico intrusion, despite the lack of apparent mineral and geotechnical variations. These results, which take into consideration long time periods in a natural, large-scale geological system, may have important implications for the long-term safety of underground storage of nuclear waste in clay formations.

  17. Geotechnical Survey, Dredgeability Of Soil Sediments And Siltation ...

    Geotechnical Survey, Dredgeability Of Soil Sediments And Siltation Volume Of Brimsu Water Reservoir. ... of the sediments was characterized by geo-technical descriptor terms, indicating that the sediments could be dredged using cutter-type dredger for excava-tion, and transported by hydraulic pipelines to disposal sites.

  18. An alternative methodology for the analysis of electrical resistivity data from a soil gas study

    Johansson, Sara; Rosqvist, Hâkan; Svensson, Mats; Dahlin, Torleif; Leroux, Virginie

    2011-08-01

    The aim of this paper is to present an alternative method for the analysis of resistivity data. The methodology was developed during a study to evaluate if electrical resistivity can be used as a tool for analysing subsurface gas dynamics and gas emissions from landfills. The main assumption of this study was that variations in time of resistivity data correspond to variations in the relative amount of gas and water in the soil pores. Field measurements of electrical resistivity, static chamber gas flux and weather data were collected at a landfill in Helsingborg, Sweden. The resistivity survey arrangement consisted of nine lines each with 21 electrodes in an investigation area of 16 ×20 m. The ABEM Lund Imaging System provided vertical and horizontal resistivity profiles every second hour. The data were inverted in Res3Dinv using L1-norm-based optimization method with a standard least-squares formulation. Each horizontal soil layer was then represented as a linear interpolated raster model. Different areas underneath the gas flux measurement points were defined in the resistivity model of the uppermost soil layer, and the vertical extension of the zones could be followed at greater depths in deeper layer models. The average resistivity values of the defined areas were calculated and plotted on a time axis, to provide graphs of the variation in resistivity with time in a specific section of the ground. Residual variation of resistivity was calculated by subtracting the resistivity variations caused by the diurnal temperature variations from the measured resistivity data. The resulting residual resistivity graphs were compared with field data of soil moisture, precipitation, soil temperature and methane flux. The results of the study were qualitative, but promising indications of relationships between electrical resistivity and variations in the relative amount of gas and water in the soil pores were found. Even though more research and better data quality is

  19. Influence of altered precipitation pattern on greenhouse gas emissions and soil enzyme activities in Pannonian soils

    Forstner, Stefan Johannes; Michel, Kerstin; Berthold, Helene; Baumgarten, Andreas; Wanek, Wolfgang; Zechmeister-Boltenstern, Sophie; Kitzler, Barbara

    2013-04-01

    Precipitation patterns are likely to be altered due to climate change. Recent models predict a reduction of mean precipitation during summer accompanied by a change in short-term precipitation variability for central Europe. Correspondingly, the risk for summer drought is likely to increase. This may especially be valid for regions which already have the potential for rare, but strong precipitation events like eastern Austria. Given that these projections hold true, soils in this area will receive water irregularly in few, heavy rainfall events and be subjected to long-lasting dry periods in between. This pattern of drying/rewetting can alter soil greenhouse gas fluxes, creating a potential feedback mechanism for climate change. Microorganisms are the key players in most soil carbon (C) and nitrogen (N) transformation processes including greenhouse gas exchange. A conceptual model proposed by Schimel and colleagues (2007) links microbial stress-response physiology to ecosystem-scale biogeochemical processes: In order to cope with decreasing soil water potential, microbes modify resource allocation patterns from growth to survival. However, it remains unclear how microbial resource acquisition via extracellular enzymes and microbial-controlled greenhouse gas fluxes respond to water stress induced by soil drying/rewetting. We designed a laboratory experiment to test for effects of multiple drying/rewetting cycles on soil greenhouse gas fluxes (CO2, CH4, N2O, NO), microbial biomass and extracellular enzyme activity. Three soils representing the main soil types of eastern Austria were collected in June 2012 at the Lysimeter Research Station of the Austrian Agency for Health and Food Safety (AGES) in Vienna. Soils were sieved to 2mm, filled in steel cylinders and equilibrated for one week at 50% water holding capacity (WHC) for each soil. Then soils were separated into two groups: One group received water several times per week (C=control), the other group received

  20. Radon gas. A review with emphasis on site investigations and measurements of soil gas and indoor house levels

    Mitchell, Seamus.

    1992-09-01

    A review of radon gas, with particular reference to its source and transport through soils and into buildings is examined. The principal parameters affecting the movement of radon has been discussed. The levels of radon gas in soils and in dwelling houses has been examined. Radon levels in the soil gas were highest in mineral soils with pear soils giving low readings but there was no significant differences between the results. Houses situated over granite and limestone bedrock gave similar results for indoor radon concentrations, with no significant differences being recorded. Results were expected to be much higher in houses over granite areas, in view of the higher uranium series activity in granites. It is concluded that high radon gas levels in soils under and in he vicinity of houses is the probable explanation for the indoor radon levels found. The influence of the underlying bedrock is not the most important parameter as was surmised before the study. (author)

  1. Correlation between indoor radon and soil gas availability: Results of field studies

    Kothari, B.K.; Kunz, C.; Lilley, W.

    1990-01-01

    To correlate indoor radon concentrations with soil gas, the authors have carried out a field survey of surficial material in selected regions of New York State. The survey consisted of measurements of gamma radiation, Ra-226, Rn-222 and the permeability for gas flow in surficial material. Based on the data, three areas with a potential for above average indoor radon concentrations have been identified: (1) a black shale region in Onondaga County; (2) a granitic region in Orange County; and (3) a black shale region in Erie County. For an area with potential for below-average indoor radon concentrations, sandy deposits on Long Island with an average concentration of 0.7 pCi Ra-226/g and 160 pCi Rn-222/L at 2-feet depth, have been selected. Fifteen homes from each of these four areas are under test for indoor radon. Measurements of air infiltration rates and soil gas availability parameters are planned for all 60 homes

  2. A new in-situ method to determine the apparent gas diffusion coefficient of soils

    Laemmel, Thomas; Paulus, Sinikka; Schack-Kirchner, Helmer; Maier, Martin

    2015-04-01

    Soil aeration is an important factor for the biological activity in the soil and soil respiration. Generally, gas exchange between soil and atmosphere is assumed to be governed by diffusion and Fick's Law is used to describe the fluxes in the soil. The "apparent soil gas diffusion coefficient" represents the proportional factor between the flux and the gas concentration gradient in the soil and reflects the ability of the soil to "transport passively" gases through the soil. One common way to determine this coefficient is to take core samples in the field and determine it in the lab. Unfortunately this method is destructive and needs laborious field work and can only reflect a small fraction of the whole soil. As a consequence insecurity about the resulting effective diffusivity on the profile scale must remain. We developed a new in-situ method using new gas sampling device, tracer gas and inverse soil gas modelling. The gas sampling device contains several sampling depths and can be easily installed into vertical holes of an auger, which allows for fast installation of the system. At the lower end of the device inert tracer gas is injected continuously. The tracer gas diffuses into the surrounding soil. The resulting distribution of the tracer gas concentrations is used to deduce the diffusivity profile of the soil. For Finite Element Modeling of the gas sampling device/soil system the program COMSOL is used. We will present the results of a field campaign comparing the new in-situ method with lab measurements on soil cores. The new sampling pole has several interesting advantages: it can be used in-situ and over a long time; so it allows following modifications of diffusion coefficients in interaction with rain but also vegetation cycle and wind.

  3. Research and application of soil-mercury-surveys method for locating uranium

    You Yunfei; Lu Shili; Jiao Zongrun

    1995-06-01

    Soil-Hg-Surveys method for locating uranium ore was presented. Soil-sampler of drilling bottom, the ability of surveying the deep uranium orebodies was raised by using this method. Application of minicomputer technology to pyrolytic-Hg-analysis raises the degree of automation and precision of the analysis. Application condition of optimum is Hg content of orebodies >1 x 10 -6 . Locating deep is about 100 m. The forecast of uranium orebodies achieved success in two unknown section that are 534 and 510 mining area, therefore two little size deposits expanded into middle size deposits. This method is as well applicable to locating gold, silver, copper, lead zinc and oil-gas natural resource and so on. (8 figs., 3 tabs.)

  4. Soil trace gas fluxes along orthogonal precipitation and soil fertility gradients in tropical lowland forests of Panama

    A. L. Matson

    2017-07-01

    Full Text Available Tropical lowland forest soils are significant sources and sinks of trace gases. In order to model soil trace gas flux for future climate scenarios, it is necessary to be able to predict changes in soil trace gas fluxes along natural gradients of soil fertility and climatic characteristics. We quantified trace gas fluxes in lowland forest soils at five locations in Panama, which encompassed orthogonal precipitation and soil fertility gradients. Soil trace gas fluxes were measured monthly for 1 (NO or 2 (CO2, CH4, N2O years (2010–2012 using vented dynamic (for NO only or static chambers with permanent bases. Across the five sites, annual fluxes ranged from 8.0 to 10.2 Mg CO2-C, −2.0 to −0.3 kg CH4-C, 0.4 to 1.3 kg N2O-N and −0.82 to −0.03 kg NO-N ha−1 yr−1. Soil CO2 emissions did not differ across sites, but they did exhibit clear seasonal differences and a parabolic pattern with soil moisture across sites. All sites were CH4 sinks; within-site fluxes were largely controlled by soil moisture, whereas fluxes across sites were positively correlated with an integrated index of soil fertility. Soil N2O fluxes were low throughout the measurement years, but the highest emissions occurred at a mid-precipitation site with high soil N availability. Net negative NO fluxes at the soil surface occurred at all sites, with the most negative fluxes at the low-precipitation site closest to Panama City; this was likely due to high ambient NO concentrations from anthropogenic sources. Our study highlights the importance of both short-term (climatic and long-term (soil and site characteristics factors in predicting soil trace gas fluxes.

  5. Plastic-bag radon gas monitor and survey results

    Torri, G.

    1990-01-01

    The Plastic-bag radon monitor used in the Italian National Survey is described. The choice of this radon gas sampler has been determined by the peculiarity of the italian environmental monitoring program, which is carried out by several different regional laboratories. Results obtained in the past using this radon monitoring device are also reported. (author). 8 refs, 7 figs

  6. National Cooperative Soil Survey (NCSS) Laboratory Data, NCSS Lab Data Mart Point Dataset

    Department of Agriculture — This layer represents the National Cooperative Soil Survey laboratory data of soil properties for soil samples taken at sites or points on the Earth’s globe – mainly...

  7. Effect of leaking natural gas on soil and vegetation in urban areas

    Hoeks, J.

    1972-01-01

    Leakage of natural gas from the gas distribution system affects the physical, chemical and biological processes in the soil. Particularly the microbial oxidation of methane is then of predominant importance for the composition of the soil gas phase. The rate of methane oxidation was

  8. Survey of stranded gas and delivered costs to Europe of selected gas resources

    Attanasi, E.D.; Freeman, P.A.

    2011-01-01

    Two important trends affecting the expected growth of global gas markets are (1) the shift by many industrialized countries from coal-fired electricity generation to the use of natural gas to generate electricity and (2) the industrialization of the heavily populated Asian countries of India and China. This paper surveys discovered gas in stranded conventional gas accumulations and presents estimates of the cost of developing and producing stranded gas in selected countries. Stranded gas is natural gas in discovered or identified fields that is not currently commercially producible for either physical or economic reasons. Published reserves of gas at the global level do not distinguish between volumes of gas in producing fields and volumes in nonproducing fields. Data on stranded gas reported here-that is the volumes, geographical distribution, and size distributions of stranded gas fields at the country and regional level-are based on the examination of individual-field data and represent a significant improvement in information available to industry and government decision makers. Globally, stranded gas is pervasive, but large volumes in large accumulations are concentrated in only a few areas. The cost component of the paper focuses on stranded conventional gas accumulations in Africa and South America that have the potential to augment supplies to Europe. The methods described for the computation of extraction and transport costs are innovative in that they use information on the sizes and geographical distribution of the identified stranded gas fields. The costs are based on industry data specific to the country and geologic basin where the stranded gas is located. Gas supplies to Europe can be increased significantly at competitive costs by the development of stranded gas. Net extraction costs of producing the identified gas depend critically on the natural-gas-liquids (NGLs) content, the prevailing prices of liquids, the size of the gas accumulation, and the

  9. A strategy for the survey of urban garden soils

    Schwartz, C.; Chenot, E. D.; Cortet, J.; Douay, F.; Dumat, C.; Pernin, C.; Pourrut, B.

    2012-04-01

    In France and all over the world, there is no systematic data available on the quality (fertility and contamination) of garden soils. Nevertheless, there is a growing need for a typology and for a method dedicated to national and international garden soil survey. This inventory is much needed in the context of environmental risk assessment, to predict the potential impact on human health of the direct contact with garden soils and of the consumption of vegetables from gardens. The state of the art on the international knowledge on garden soils, gardening practices and food production, shows that gardens remain poorly known and very complex ecological, economical and social systems. Their global quality is the result of a wide number of factors including environment, history, specific characteristics of the gardens, gardeners and their practices, plant and/or animal productions and socio-economic context. The aim is then to better know the determinism of the agronomic, environmental and sanitary properties of gardens as a function of gardening practices and their impact on the quality of soils and plants. We propose a definition of "garden" and more generally of all the field "garden". The system "garden" is represented by attributes (soil and plant characteristics) and factors with various impacts (e.g. environment > soil parent material > former land uses > age and sex of gardener > gardening practices > socio-professional group > type and proportion of productions > climate > age of the garden > size of the garden > education, information > cultural origin > functions of the garden > regulations). A typology of gardens including 7 selected factors and associated categories and a method for describing, sampling and characterizing a population of gardens representative (for a country) are proposed. Based on the statistical analysis on regional databases, we have determined and proposed an optimum size for the collected population of garden soils. The discussion of

  10. Estimating methane gas production in peat soils of the Florida Everglades using hydrogeophysical methods

    Wright, William; Comas, Xavier

    2016-04-01

    The spatial and temporal variability in production and release of greenhouse gases (such as methane) in peat soils remains uncertain, particularly for low-latitude peatlands like the Everglades. Ground penetrating radar (GPR) is a hydrogeophysical tool that has been successfully used in the last decade to noninvasively investigate carbon dynamics in peat soils; however, application in subtropical systems is almost non-existent. This study is based on four field sites in the Florida Everglades, where changes in gas content within the soil are monitored using time-lapse GPR measurements and gas releases are monitored using gas traps. A weekly methane gas production rate is estimated using a mass balance approach, considering gas content estimated from GPR, gas release from gas traps and incorporating rates of diffusion, and methanotrophic consumption from previous studies. Resulting production rates range between 0.02 and 0.47 g CH4 m-2 d-1, falling within the range reported in literature. This study shows the potential of combining GPR with gas traps to monitor gas dynamics in peat soils of the Everglades and estimate methane gas production. We also show the enhanced ability of certain peat soils to store gas when compared to others, suggesting that physical properties control biogenic gas storage in the Everglades peat soils. Better understanding biogenic methane gas dynamics in peat soils has implications regarding the role of wetlands in the global carbon cycle, particularly under a climate change scenario.

  11. Tunguska, 1908: the gas pouch and soil fluidization hypothesis

    Nistor, I.

    2012-01-01

    The Siberian taiga explosion of 30 June 1908 remains one of the great mysteries of the 20th century: millions of trees put down over an area of 2200 km2 without trace of a crater or meteorite fragments. Hundred years of failed searches have followed, resulting in as many flawed hypothesis which could not offer satisfactory explanations: meteorite, comet, UFO, etc. In the author's opinion, the cause is that the energy the explorers looked for was simply not there! The author's hypothesis is that a meteoroid encountered a gas pouch in the atmosphere, producing a devastating explosion, its effects being amplified by soil fluidization.

  12. Soil Survey Geographic (SSURGO) Soil Polygons for the State of Rhode Island: Bristol, Kent, Newport, Providence, and Washington Counties

    University of Rhode Island Geospatial Extension Program — 2013 VERSION 6 Spatial: This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative...

  13. Soil gas 222Rn and volcanic activity at El Hierro (Canary Islands) before and after the 2011 submarine eruption

    Padilla, G.; Hernández, P. A.; Padrón, E.; Barrancos, J.; Melián, G.; Dionis, S.; Rodríguez, F.; Nolasco, D.; Calvo, D.; Hernández, I.; Pereza, M. D.; Pérez, N. M.

    2012-04-01

    El Hierro (278 km2) is the southwesternmost island of the Canarian archipelago. From June 19, 2011 to January 2012, more than 11,950 seismic events have been detected by the seismic network of IGN. On 10 October 2011 the earthquake swarm changed its behaviour and produced a harmonic tremor due to magma movement, indicating that a submarine eruption located at 2 km south of La Restinga had started which is still in progress. Since 2003, the ITER Environmental Research Division now integrated in the Instituto Volcanológico de Canarias, INVOLCAN, has regularly performed soil gas surveys at El Hierro as a geochemical tool for volcanic surveillance. Among the investigated gases, soil gas radon (222Rn) and thoron (220Rn) have played a special attention. Both gases are characterized to ascend towards the surface mainly through cracks or faults via diffusion or advection, mechanisms dependent of both soil porosity and permeability, which in turn vary as a function of the stress/strain changes at depth. Years before the starts of the volcanic-seismic crisis on July 17, 2011, a volcanic multidisciplinary surveillance program was implemented at El Hierro including discrete and continuous measurements of 222Rn and 220Rn. Two soil gas 222Rn surveys had been carried out at El Hierro in 2003 and 2011, and four continuous geochemical monitoring stations for 222Rn and 220Rn measurements had been installed (HIE02, HIE03, HIE04 and HIE08). Soil gas 222Rn surveys were carried out at the surface environment of El Hierro after selecting 600 sampling observation sites (about 40 cm depth). Geochemical stations measure 222Rn and 220Rn activities by pumping the gas from a PVC pipe inserted 1m in the ground and thermally isolated. The results of the 2003 and 2011 soil gas 222Rn surveys show clearly a relatively higher observed 222Rn activities in the surface environment on 2011 than those observed on 2003 when no anomalous seismicity were taking place beneath El Hierro. The observed

  14. Determination of radon concentration in soil gas by gamma-ray spectrometry of olive oil

    Al-Azmi, Darwish; Karunakara, N.

    2007-01-01

    Measurements of radon concentration in soil gas have been carried out using a bubbling system in which the soil gas is drawn through an active pumping to bubble a liquid absorber (olive oil) for the deposition of the soil gas in it. After the bubbling process, the absorber is then taken for gamma-ray measurements. Gamma-ray photopeaks from the 214 Pb and the 214 Bi radon progeny are considered for the detection of the 222 Rn gas to study the concentration levels for radon soil gas. Results for some field measurements were obtained and compared with results obtained using AlphaGuard radon gas monitor. The technique provides a possible approach for the measurements of radon soil gas with gamma-ray spectrometry

  15. Assessment of hyporheic zone, flood-plain, soil-gas, soil, and surface-water contamination at the Old Incinerator Area, Fort Gordon, Georgia, 2009-2010

    Guimaraes, Wladmir B.; Falls, W. Fred; Caldwell, Andral W.; Ratliff, W. Hagan; Wellborn, John B.; Landmeyer, James E.

    2011-01-01

    The U.S. Geological Survey, in cooperation with the U.S. Department of the Army Environmental and Natural Resources Management Office of the U.S. Army Signal Center and Fort Gordon, Georgia, assessed the hyporheic zone, flood plain, soil gas, soil, and surface-water for contaminants at the Old Incinerator Area at Fort Gordon, from October 2009 to September 2010. The assessment included the detection of organic contaminants in the hyporheic zone, flood plain, soil gas, and surface water. In addition, the organic contaminant assessment included the analysis of explosives and chemical agents in selected areas. Inorganic contaminants were assessed in soil and surface-water samples. The assessment was conducted to provide environmental contamination data to the U.S. Army at Fort Gordon pursuant to requirements of the Resource Conservation and Recovery Act Part B Hazardous Waste Permit process. Total petroleum hydrocarbons were detected above the method detection level in all 13 samplers deployed in the hyporheic zone and flood plain of an unnamed tributary to Spirit Creek. The combined concentrations of benzene, toluene, ethylbenzene, and total xylene were detected at 3 of the 13 samplers. Other organic compounds detected in one sampler included octane and trichloroethylene. In the passive soil-gas survey, 28 of the 60 samplers detected total petroleum hydrocarbons above the method detection level. Additionally, 11 of the 60 samplers detected the combined masses of benzene, toluene, ethylbenzene, and total xylene above the method detection level. Other compounds detected above the method detection level in the passive soil-gas survey included octane, trimethylbenzene, perchlorethylene, and chloroform. Subsequent to the passive soil-gas survey, six areas determined to have relatively high contaminant mass were selected, and soil-gas samplers were deployed, collected, and analyzed for explosives and chemical agents. No explosives or chemical agents were detected above

  16. Nitrogen transformations and greenhouse gas emissions from a riparian wetland soil: An undisturbed soil column study

    Munoz-Leoz, Borja [Department of Chemical and Environmental Engineering, University of the Basque Country, UPV/EHU, E-48013 Bilbao (Spain); Antigueedad, Inaki [Department of Geodynamic, University of the Basque Country, UPV/EHU, E-48940 Leioa (Spain); Garbisu, Carlos [Department of Ecosystems, NEIKER-Tecnalia, E-48160 Derio (Spain); Ruiz-Romera, Estilita, E-mail: estilita.ruiz@ehu.es [Department of Chemical and Environmental Engineering, University of the Basque Country, UPV/EHU, E-48013 Bilbao (Spain)

    2011-01-15

    Riparian wetlands bordering intensively managed agricultural fields can act as biological filters that retain and transform agrochemicals such as nitrate and pesticides. Nitrate removal in wetlands has usually been attributed to denitrification processes which in turn imply the production of greenhouse gases (CO{sub 2} and N{sub 2}O). Denitrification processes were studied in the Salburua wetland (northern Spain) by using undisturbed soil columns which were subsequently divided into three sections corresponding to A-, Bg- and B2g-soil horizons. Soil horizons were subjected to leaching with a 200 mg NO{sub 3}{sup -} L{sup -1} solution (rate: 90 mL day{sup -1}) for 125 days at two different temperatures (10 and 20 {sup o}C), using a new experimental design for leaching assays which enabled not only to evaluate leachate composition but also to measure gas emissions during the leaching process. Column leachate samples were analyzed for NO{sub 3}{sup -} concentration, NH{sub 4}{sup +} concentration, and dissolved organic carbon. Emissions of greenhouse gases (CO{sub 2} and N{sub 2}O) were determined in the undisturbed soil columns. The A horizon at 20 {sup o}C showed the highest rates of NO{sub 3}{sup -} removal (1.56 mg N-NO{sub 3}{sup -} kg{sup -1} DW soil day{sup -1}) and CO{sub 2} and N{sub 2}O production (5.89 mg CO{sub 2} kg{sup -1} DW soil day{sup -1} and 55.71 {mu}g N-N{sub 2}O kg{sup -1} DW soil day{sup -1}). For the Salburua wetland riparian soil, we estimated a potential nitrate removal capacity of 1012 kg N-NO{sub 3}{sup -} ha{sup -1} year{sup -1}, and potential greenhouse gas emissions of 5620 kg CO{sub 2} ha{sup -1} year{sup -1} and 240 kg N-N{sub 2}O ha{sup -1} year{sup -1}. - Research Highlights: {yields}A new experimental design is proposed for leaching assays to simulate nitrogen transformations in riparian wetland soil. {yields}Denitrification is the main process responsible for nitrate removal in the riparian zone of Salburua wetland. {yields

  17. Radon anomaly in soil gas as an earthquake precursor

    Miklavcic, I.; Radolic, V.; Vukovic, B.; Poje, M.; Varga, M.; Stanic, D.; Planinic, J.

    2008-01-01

    The mechanical processes of earthquake preparation are always accompanied by deformations; afterwards, the complex short- or long-term precursory phenomena can appear. Anomalies of radon concentrations in soil gas are registered a few weeks or months before many earthquakes. Radon concentrations in soil gas were continuously measured by the LR-115 nuclear track detectors at site A (Osijek) during a 4-year period, as well as by the Barasol semiconductor detector at site B (Kasina) during 2 years. We investigated the influence of the meteorological parameters on the temporal radon variations, and we determined the equation of the multiple regression that enabled the reduction (deconvolution) of the radon variation caused by the barometric pressure, rainfall and temperature. The pre-earthquake radon anomalies at site A indicated 46% of the seismic events, on criterion M≥3, R<200 km, and 21% at site B. Empirical equations between earthquake magnitude, epicenter distance and precursor time enabled estimation or prediction of an earthquake that will rise at the epicenter distance R from the monitoring site in expecting precursor time T

  18. Radon anomaly in soil gas as an earthquake precursor

    Miklavcic, I.; Radolic, V.; Vukovic, B.; Poje, M.; Varga, M.; Stanic, D. [Department of Physics, University of Osijek, Trg Ljudevita Gaja 6, POB 125, 31000 Osijek (Croatia); Planinic, J. [Department of Physics, University of Osijek, Trg Ljudevita Gaja 6, POB 125, 31000 Osijek (Croatia)], E-mail: planinic@ffos.hr

    2008-10-15

    The mechanical processes of earthquake preparation are always accompanied by deformations; afterwards, the complex short- or long-term precursory phenomena can appear. Anomalies of radon concentrations in soil gas are registered a few weeks or months before many earthquakes. Radon concentrations in soil gas were continuously measured by the LR-115 nuclear track detectors at site A (Osijek) during a 4-year period, as well as by the Barasol semiconductor detector at site B (Kasina) during 2 years. We investigated the influence of the meteorological parameters on the temporal radon variations, and we determined the equation of the multiple regression that enabled the reduction (deconvolution) of the radon variation caused by the barometric pressure, rainfall and temperature. The pre-earthquake radon anomalies at site A indicated 46% of the seismic events, on criterion M{>=}3, R<200 km, and 21% at site B. Empirical equations between earthquake magnitude, epicenter distance and precursor time enabled estimation or prediction of an earthquake that will rise at the epicenter distance R from the monitoring site in expecting precursor time T.

  19. Assessment of Soil-Gas and Soil Contamination at the Former Military Police Range, Fort Gordon, Georgia, 2009-2010

    Falls, W. Fred; Caldwell, Andral W.; Guimaraes, Wladmir B.; Ratliff, W. Hagan; Wellborn, John B.; Landmeyer, James E.

    2011-01-01

    Soil gas and soil were assessed for organic and inorganic contaminants at the former military police range at Fort Gordon, Georgia, from May to September 2010. The assessment evaluated organic contaminants in soil-gas samplers and inorganic contaminants in soil samples. This assessment was conducted to provide environmental contamination data to Fort Gordon pursuant to requirements of the Resource Conservation and Recovery Act Part B Hazardous Waste Permit process. Soil-gas samplers deployed and collected from May 20 to 24, 2010, identified masses above method detection level for total petroleum hydrocarbons, gasoline-related and diesel-related compounds, and chloroform. Most of these detections were in the southwestern quarter of the study area and adjacent to the road on the eastern boundary of the site. Nine of the 11 chloroform detections were in the southern half of the study area. One soil-gas sampler deployed adjacent to the road on the southern boundary of the site detected a mass of tetrachloroethene greater than, but close to, the method detection level of 0.02 microgram. For soil-gas samplers deployed and collected from September 15 to 22, 2010, none of the selected organic compounds classified as chemical agents and explosives were detected above method detection levels. Inorganic concentrations in the five soil samples collected at the site did not exceed the U.S. Environmental Protection Agency regional screening levels for industrial soil and were at or below background levels for similar rocks and strata in South Carolina.

  20. Basic Survey Small-scale Natural Gas Consumption (BAK 1995)

    Bos, R.E.J.; Weegink, R.J.

    1996-01-01

    The annual title survey shows for 1995 that Dutch households consumed more than 120 million m 3 of natural gas, which is higher than in 1994. The average consumption per dwelling slightly decreased. Gas consumption for cooking and hot water remained the same. The slight decrease in the average consumption is caused by space heating. The decrease seemed to halt last year, but still continues for the time being. However, it is too early to refer to it as a trend. 3 figs., 7 tabs

  1. Greenhouse gas emissions from agricultural soils in Austria

    Strebl, F.; Gebetsroither, E.; Orthofer, R.

    2002-07-01

    This report documents the calculations of anthropogenic greenhouse gas emissions in Austria of the IPCC-sector 'Agricultural Soils' for the period 1980 to 2001. According to available information, CH 4 emissions from agricultural soils are very small and thus irrelevant. N 2 O emissions were calculated according to the IPCC method; emission sources considered include direct emissions from nitrogen inputs to soils (mineral and organic fertilizers, crop residues, sewage sludge application, biological fixation) as well as indirect emissions (from atmospheric nitrogen deposition and nitrogen leaching) plus emissions from nitrogen input through grazing animal excreta. NH 3 and NO x emissions were calculated according to the CORINAIR method; sources considered were nitrogen inputs through fertilization as well as emissions from unfertilized cultures. In the year 1990 total emissions were 5.680 t N 2 O-N, 24.628 t NH 3 -N and 1.376 t NO x N. In the period 1980-2001 there were considerable fluctuations of emissions, caused by an inter annual variability of crop production and fertilizer consumption data. However, there are no significant emission trends in the past 20 years. Uncertainties were determined through a Monte-Carlo-based simulation; the standard deviation of a normal uncertainty distribution is 24 % for N 2 O, 13 % for NH 3 , and 18 % for NO x . (author)

  2. Monitoring soil greenhouse gas emissions from managed grasslands

    Díaz-Pinés, Eugenio; Lu, Haiyan; Butterbach-Bahl, Klaus; Kiese, Ralf

    2014-05-01

    Grasslands in Central Europe are of enormous social, ecological and economical importance. They are intensively managed, but the influence of different common practices (i.e. fertilization, harvesting) on the total greenhouse gas budget of grasslands is not fully understood, yet. In addition, it is unknown how these ecosystems will react due to climate change. Increasing temperatures and changing precipitation will likely have an effect on productivity of grasslands and on bio-geo-chemical processes responsible for emissions of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). In the frame of the TERENO Project (www.tereno.net), a long-term observatory has been implemented in the Ammer catchment, southern Germany. Acting as an in situ global change experiment, 36 big lysimeters (1 m2 section, 150 cm height) have been translocated along an altitudinal gradient, including three sites ranging from 600 to 860 meters above sea level. In addition, two treatments have been considered, corresponding to different management intensities. The overall aim of the pre-alpine TERENO observatory is improving our understanding of the consequences of climate change and management on productivity, greenhouse gas balance, soil nutritional status, nutrient leaching and hydrology of grasslands. Two of the sites are equipped with a fully automated measurement system in order to continuously and accurately monitor the soil-atmosphere greenhouse gas exchange. Thus, a stainless steel chamber (1 m2 section, 80 cm height) is controlled by a robotized system. The chamber is hanging on a metal structure which can move both vertically and horizontally, so that the chamber is able to be set onto each of the lysimeters placed on the field. Furthermore, the headspace of the chamber is connected with a gas tube to a Quantum Cascade Laser, which continuously measures CO2, CH4, N2O and H2O mixing ratios. The chamber acts as a static chamber and sets for 15 minutes onto each lysimeter

  3. A survey of radioactive caesium in British soils

    Cawse, P.A.; Baker, S.J.

    1990-08-01

    The accumulation of radioactive caesium-137 in soils under permanent grassland was measured by Harwell Laboratory in 1977. The objective was to provide at selected locations in Great Britain a reference of background radioactivity in soil resulting from depositions of nuclear weapons fallout over some thirty years. Following the Chernobyl reactor accident in April 1986, the Department of the Environment requested further measurements at the reference sites in 1987 to record changes and regional differences in the amounts present in soil caused by radioactive fallout. Results from the 1987 survey generally showed the highest accumulations of Cs-137 derived from both nuclear weapons and Chernobyl fallout in western and northern regions of Great Britain, owing to the effectiveness of rainfall on scavenging of radioactivity from the atmosphere. Thus the reference sites in south-west and central Scotland had the maximum accumulation of 26kBq Cs-137/m 2 to 30cm soil depth, at Burrow Head and Rannoch; at these locations the soil concentrations attained 256Bq/kg whereas at all sites in England levels were 2 . To 30cm depth, an average soil concentration in Scotland of ∼ 100Bq/kg was derived, which is 11% of the generalised derived limit (GDL). Comparison of 1987 results with decay-corrected 1977 data showed that nine locations in England receiving negligible Chernobyl fallout had a net loss of Cs-137 by soil erosion and/or leaching over the ten-years interval. At other locations in England a minimum of 6-40% of Cs-137 to 30cm depth was Chernobyl-derived, but this increased to 50-95% in Scotland where substantial accumulations of Cs-134 were also recorded. At the two peat sites in north-east Scotland the accumulated deposition of Cs-137 in 1987 was two and five-fold greater than in 1977. In peatland vegetation the concentrations of Cs-137 followed the order sphagnum mosses > heather > g

  4. Soil gas and radon entry potential measurements in central Florida houses

    Turk, B.H.

    1993-01-01

    A technique to quantify the various parameters associated with the pressure-driven entry rate of soil gas and radon into buildings has been applied to five central Florida houses with slab-on-grade construction. Results indicate that the slabs of these Florida houses are more resistant to soil gas flow than slabs in previously studied New Jersey and New Mexico houses. The data for locations near the slab perimeter show that the resistance to soil gas flow is greater for the slab than for the underlying materials/soils, implying that the slab resistance is a slightly dominant factor controlling soil gas entry in these houses. As in the New Jersey and New Mexico houses, soil gas and radon entry potentials were highest near the slab perimeters. In contrast to the earlier studies, geometric mean radon entry potentials did not correlate well with measured indoor radon levels. (orig.). (4 refs., 1 fig., 2 tabs.)

  5. Underground gas storage in the World - Cedigaz survey

    Benquey, R.

    2010-01-01

    The 2010 edition of 'Underground Gas Storage in the World' provides an update to the previous survey released by CEDIGAZ in 2006. At that time, 610 underground gas storage (UGS) facilities were in operation worldwide, with a working capacity of 319 billion cubic metres (bcm). As of 1 January 2010, this number had reached 642 facilities with a working gas capacity of 333 bcm, or 10.8% of world gas consumption. By 2020, the global UGS demand is expected to grow at a pace of 3.3% per year, and according to the projects identified, more than 760 UGS sites could be active in the world with a total working capacity of approximately 465 bcm. In this survey, CEDIGAZ analyses the following trends which characterise the rapid development of underground gas storage in the world: - the strong dynamics of the European storage market, where 127 projects could add 75 bcm of working capacity by 2020, - the continued development of the UGS market in the United States (49 projects), encouraged by market-based rates allowed by the FERC, and rapid permitting processes, - the development of facilities in countries with little or no storage capacities at present, in Asia/Oceania, the C.I.S., and Eastern Europe in particular. This survey provides an analysis of the recent evolutions in the technic-economic aspects of the underground gas storage business, as well as an overview of the UGS markets and their developments in the world, country by country. A specific section is dedicated to the analysis of future UGS needs in Europe by 2020: - Technic-economic aspects of UGS: This part of the survey analyses the latest technical improvements and research axes in the field of underground gas storage. As it is more difficult to build greenfield storage facilities, a lot of work has been done to improve the performance and flexibility of existing storage sites. This section also deals with the evolution of investment and operational costs in storage over the last few years. Furthermore, the

  6. Handheld Multi-Gas Meters Market Survey Report

    Williams, Gustavious [Brigham Young Univ., Provo, UT (United States); Wald-Hopkins, Mark David [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Obrey, Stephen J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Akhadov, Valida Dushdurova [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-06-23

    Handheld multi-gas meters (MGMs) are equipped with sensors to monitor oxygen (O2) levels and additional sensors to detect the presence of combustible or toxic gases in the environment. This report is limited to operational response-type MGMs that include at least four different sensors. These sensors can vary by type and by the chemical monitored. In real time, the sensors report the concentration of monitored gases in the atmosphere near the MGM. To provide emergency responders with information on handheld multi-gas meters, the System Assessment and Validation for Emergency Responders (SAVER) Program conducted a market survey. This market survey report is based on information gathered between November 2015 and February 2016 from vendors, Internet research, industry publications, an emergency responder focus group, and a government issued Request for Information (RFI) that was posted on the Federal Business Opportunities website.

  7. Correlations of soil-gas and indoor radon with geology in glacially derived soils of the northern Great Plains

    Schumann, R.R.; Owen, D.E.; Peake, R.T.; Schmidt, K.M.

    1990-01-01

    This paper reports that a higher percentage of homes in parts of the northern Great Plains underlain by soils derived from continental glacial deposits have elevated indoor radon levels (greater than 4 pCi/L) than any other area in the country. Soil-gas radon concentrations, surface radioactivity, indoor radon levels, and soil characteristics were studied in areas underlain by glacially-derived soils in North Dakota and Minnesota to examine the factors responsible for these elevated levels. Clay-rich till soils in North Dakota have generally higher soil-gas radon levels, and correspondingly higher indoor radon levels, than the sandy till soils common to west-central Minnesota. Although the proportions of homes with indoor radon levels greater than 4 pCi/L are similar in both areas, relatively few homes underlain by sandy tills have screening indoor radon levels greater than 20 pCi/L, whereas a relatively large proportion of homes underlain by clayey tills have screening indoor radon levels exceeding 20 pCi/L. The higher radon levels in North Dakota are likely due to enhanced emanation from the smaller grains and to relatively higher soil radium concentrations in the clay-rich soils, whereas the generally higher permeability of the sandy till soils in Minnesota allows soil gas to be drawn into structures from a larger source volume, increasing indoor radon levels in these areas

  8. Turning soil survey data into digital soil maps in the Energy Region Eger Research Model Area

    Pásztor, László; Dobos, Anna; Kürti, Lívia; Takács, Katalin; Laborczi, Annamária

    2015-04-01

    Agria-Innoregion Knowledge Centre of the Eszterházy Károly College has carried out targeted basic researches in the field of renewable energy sources and climate change in the framework of TÁMOP-4.2.2.A-11/1/KONV project. The project has covered certain issues, which require the specific knowledge of the soil cover; for example: (i) investigation of quantitative and qualitative characteristics of natural and landscape resources; (ii) determination of local amount and characteristics of renewable energy sources; (iii) natural/environmental risk analysis by surveying the risk factors. The Energy Region Eger Research Model Area consists of 23 villages and is located in North-Hungary, at the Western part of Bükkalja. Bükkalja is a pediment surface with erosional valleys and dense river network. The diverse morphology of this area results diversity in soil types and soil properties as well. There was large-scale (1:10,000 and 1:25,000 scale) soil mappings in this area in the 1960's and 1970's which provided soil maps, but with reduced spatial coverage and not with fully functional thematics. To achive the recent tasks (like planning suitable/optimal land-use system, estimating biomass production and development of agricultural and ecomonic systems in terms of sustainable regional development) new survey was planned and carried out by the staff of the College. To map the soils in the study area 10 to 22 soil profiles were uncovered per settlement in 2013 and 2014. Field work was carried out according to the FAO Guidelines for Soil Description and WRB soil classification system was used for naming soils. According to the general goal of soil mapping the survey data had to be spatially extended to regionalize the collected thematic local knowledge related to soil cover. Firstly three thematic maps were compiled by digital soil mapping methods: thickness of topsoil, genetic soil type and rate of surface erosion. High resolution digital elevation model, Earth

  9. Market for oil and gas assets defined in survey

    Taggart, L.; Murry, D.A.

    1991-01-01

    This paper reports that hundreds of companies are currently active in the oil and gas acquisition and disposition marketplace, but unfortunately, the entire sale process within the industry continues to operate inefficiently. The mechanism for selling oil and gas properties in this secondary market - as used here, a term that excludes initial investments in oil and gas assets and sales of drilling program shares - is sort of catch-as-catch- can. Identifying who is seeking what type of property at any time is difficult, bordering on guesswork. A recent survey of 186 company representatives and individuals, who declared themselves as in the market, disclosed some of this information at a point in time

  10. Hydrocarbon and Carbon Dioxide Fluxes from Natural Gas Well Pad Soils and Surrounding Soils in Eastern Utah.

    Lyman, Seth N; Watkins, Cody; Jones, Colleen P; Mansfield, Marc L; McKinley, Michael; Kenney, Donna; Evans, Jordan

    2017-10-17

    We measured fluxes of methane, nonmethane hydrocarbons, and carbon dioxide from natural gas well pad soils and from nearby undisturbed soils in eastern Utah. Methane fluxes varied from less than zero to more than 38 g m -2 h -1 . Fluxes from well pad soils were almost always greater than from undisturbed soils. Fluxes were greater from locations with higher concentrations of total combustible gas in soil and were inversely correlated with distance from well heads. Several lines of evidence show that the majority of emission fluxes (about 70%) were primarily due to subsurface sources of raw gas that migrated to the atmosphere, with the remainder likely caused primarily by re-emission of spilled liquid hydrocarbons. Total hydrocarbon fluxes during summer were only 39 (16, 97)% as high as during winter, likely because soil bacteria consumed the majority of hydrocarbons during summer months. We estimate that natural gas well pad soils account for 4.6 × 10 -4 (1.6 × 10 -4 , 1.6 × 10 -3 )% of total emissions of hydrocarbons from the oil and gas industry in Utah's Uinta Basin. Our undisturbed soil flux measurements were not adequate to quantify rates of natural hydrocarbon seepage in the Uinta Basin.

  11. Direct monitoring of wind-induced pressure-pumping on gas transport in soil

    Laemmel, Thomas; Mohr, Manuel; Schindler, Dirk; Schack-Kirchner, Helmer; Maier, Martin

    2017-04-01

    Gas exchange between soil and atmosphere is important for the biogeochemistry of soils and is commonly assumed to be governed by molecular diffusion. Yet a few previous field studies identified other gas transport processes such as wind-induced pressure-pumping to enhance soil-atmosphere fluxes significantly. However, since these wind-induced non-diffusive gas transport processes in soil often occur intermittently, the quantification of their contribution to soil gas emissions is challenging. To quantify the effects of wind-induced pressure-pumping on soil gas transport, we developed a method for in situ monitoring of soil gas transport. The method includes the use of Helium (He) as a tracer gas which was continuously injected into the soil. The resulting He steady-state concentration profile was monitored. Gas transport parameters of the soil were inversely modelled. We used our method during a field campaign in a well-aerated forest soil over three months. During periods of low wind speed, soil gas transport was modelled assuming diffusion as transport process. During periods of high wind speed, the previously steady diffusive He concentration profile showed temporary concentration decreases in the topsoil, indicating an increase of the effective gas transport rate in the topsoil up to 30%. The enhancement of effective topsoil soil gas diffusivity resulted from wind-induced air pressure fluctuations which are referred to as pressure-pumping. These air pressure fluctuations had frequencies between 0.1 and 0.01 Hz and amplitudes up to 10 Pa and occurred at above-canopy wind speeds greater than 5 m s-1. We could show the importance of the enhancement of the gas transport rate in relation with the wind intensity and corresponding air pressure fluctuations characteristics. We directly detected and quantified the pressure-pumping effect on gas transport in soil in a field study for the first time, and could thus validate and underpin the importance of this non

  12. The survey of occupational accidents in Yazd gas agency (2013

    Amir Hossein Khoshakhlagh

    2016-10-01

    Full Text Available Background: Existence of coordinated and professional safety system to prevent occurrence of accidents and potential hazards seem to be essential in installing networks of gas distribution projects. Objective: To survey work-related accidents and safety performance indices in project implementation unit of Yazd gas agency. Methods: This analytical study was conducted on 197 of workforce in Yazd gas agency in 2013 that were selected by census and they were male. Demographic and accident information were gathered using a self-made questionnaire and face- to- face interview, and required information obtained from dossier to determine the safety performance indicators. Safety performance indicators were calculated in separately of 13 types occupations in project implementation unit of gas agency and data were analyzed using T-test. Findings: The highest accident frequency and severity rate were related to digging occupation and then metal line welding. Consequences of accidents were cuts (%56.7 and soreness (%14.9. The causes of accidents were related to uselessness of personal protective equipment (%25.2 and lack of precision in the task (%19.3. The highest rate of accident was observed among the age group 20-29 years with work experience of 4-6 years. Conclusion: According to the findings of this study and the risk of gas processes, it seems to be necessary the implementation of integrated management systems and training of workers about safety rules to improve the safety culture and prevent accidents.

  13. Causes of poor sealant performance in soil gas resistant foundations

    Scott, A.

    1993-01-01

    The surface permeability of concrete walls and floors in houses was measured with a specially designed permeameter, based on measuring the air-flow induced by a pressure difference across a temporary test seal applied to a surface. The permeability of bulk concrete is 10 -16 m 2 . Areas free of surface defects had permeability ranging from 10 -14 to 10- 16 m 2 . However, surface defects are common on concrete wall surfaces, which increase the permeability to >10 -12 m 2 . This is too high for standard seal designs to be adequate as the only method of soil gas and radon exclusion. Satisfactory seals require either extended contact width or mechanical removal of the surface layer. (orig.). (2 figs., 1 tab.)

  14. Radon survey related to construction materials and soils in Zacatecas, Mexico using LR-115

    Mireles, F.; Garcia, M.L.; Quirino, L.L.; Davila, J.I.; Pinedo, J.L.; Rios, C.; Montero, M.E.; Colmenero, L.; Villalba, L.

    2007-01-01

    Indoor radon gas ( 222 Rn), present in the air inside buildings, is one of the most important sources of radiation exposure to the population. This gas originates in the 238 U radioactive decay chain, which is contained in rock and solid soil particles. Radon accumulation in confined spaces, inside buildings, depends on several factors such as the type of soils, type of constructions, building materials, and ventilation. The aim of this work is to present indoor and outdoor radon concentrations for 202 dwellings and indoor concentrations for 148 public clinics; and the radon concentrations relate to the type of predominant soils, the construction years; and building materials used in the ceilings, walls and floors, for cities and towns of the 57 municipalities in the State of Zacatecas, Mexico. The 222 Rn concentrations were measured with a passive-type radon monitor, with LR-115 as detector material; and the radon survey was made during four stages of three months each throughout Zacatecas from 2001 to 2002. The indoor and outdoor radon concentration averages in dwellings were 55.6±4.9Bqm -3 and 46.5±5.3Bqm -3 , respectively. The indoor radon concentration average in public clinics was 57.8±5.4Bqm -3 . These values were lower than the US EPA action limit of 148Bqm -3

  15. Soil Survey Geographic (SSURGO) Special Point Features for the State of Rhode Island: Bristol, Kent, Newport, Providence, and Washington Counties

    University of Rhode Island Geospatial Extension Program — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  16. Soil Survey Geographic (SSURGO) Special Line Features for the State of Rhode Island: Bristol, Kent, Newport, Providence, and Washington County

    University of Rhode Island Geospatial Extension Program — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  17. Soil Survey Geographic (SSURGO) database for Shiprock Area, Parts of San Juan County, New Mexico and Apache County, Arizona

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  18. Soil Survey Geographic (SSURGO) database for Cibola Area, New Mexico, Parts of Cibola, McKinley, and Valencia Counties

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  19. Soil Survey Geographic (SSURGO) database for Rio Arriba Area, New Mexico, Parts of Rio Arriba and Sandoval Counties

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  20. Soil Survey Geographic (SSURGO) database for Gila National Forest, New Mexico, Parts of Catron, Grant and Sierra Counties

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  1. Soil Survey Geographic (SSURGO) database for Bernalillo County and Parts of Sandoval and Valencia Counties, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  2. Soil Survey Geographic (SSURGO) database for Jicarilla Apache Nation, Parts of Rio Arriba and Sandoval Counties, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  3. Soil Survey Geographic (SSURGO) database for Lincoln National Forest Area, New Mexico, Parts of Lincoln and Otero Counties

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  4. Soil Survey Geographic (SSURGO) database for Taos County and Parts of Rio Arriba and Mora Counties, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  5. Soil Survey Geographic (SSURGO) database for Sandoval County Area, New Mexico (Parts of Los Alamos, Sandoval and Rio Arriba Counties)

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  6. Assessment of groundwater, soil-gas, and soil contamination at the Vietnam Armor Training Facility, Fort Gordon, Georgia, 2009-2010

    Guimaraes, Wladmir B.; Falls, W. Fred; Caldwell, Andral W.; Ratliff, W. Hagan; Wellborn, John B.; Landmeyer, James E.

    2011-01-01

    The U.S. Geological Survey, in cooperation with the U.S. Department of the Army Environmental and Natural Resources Management Office of the U.S. Army Signal Center and Fort Gordon, Georgia, assessed the groundwater, soil gas, and soil for contaminants at the Vietnam Armor Training Facility (VATF) at Fort Gordon, from October 2009 to September 2010. The assessment included the detection of organic compounds in the groundwater and soil gas, and inorganic compounds in the soil. In addition, organic contaminant assessment included organic compounds classified as explosives and chemical agents in selected areas. The assessment was conducted to provide environmental contamination data to the U.S. Army at Fort Gordon pursuant to requirements of the Resource Conservation and Recovery Act Part B Hazardous Waste Permit process. Four passive samplers were deployed in groundwater wells at the VATF in Fort Gordon. Total petroleum hydrocarbons were detected above the method detection level at all four wells. The only other volatile organic compounds detected above their method detection level were undecane and pentadecane, which were detected in two of the four wells sampled. Soil-gas samplers were deployed at 72 locations in a grid pattern across the VATF. Total petroleum hydrocarbons were detected in 71 of the 72 samplers (one sampler was destroyed in the field and not analyzed) at levels above the method detection level, and the combined mass of benzene, toluene, ethylbenzene, and total xylene was detected above the detection level in 31 of the 71 samplers that were analyzed. Other volatile organic compounds detected above their respective method detection levels were naphthalene, 2-methyl-naphthalene, tridecane, 1,2,4-trimethylbenzene, and perchloroethene. Subsequent to the soil-gas survey, four areas determined to have elevated contaminant mass were selected and sampled for explosives and chemical agents. No detections of explosives or chemical agents above their

  7. Assessment of soil-gas, soil, and water contamination at the former 19th Street landfill, Fort Gordon, Georgia, 2009-2010

    Falls, W. Fred; Caldwell, Andral W.; Guimaraes, Wladmir B.; Ratliff, W. Hagan; Wellborn, John B.; Landmeyer, James E.

    2011-01-01

    Soil gas, soil, and water were assessed for organic and inorganic constituents at the former 19th Street landfill at Fort Gordon, Georgia, from February to September 2010. Passive soil-gas samplers were analyzed to evaluate organic constituents in the hyporheic zone and flood plain of a creek and soil gas within the estimated boundaries of the former landfill. Soil and water samples were analyzed to evaluate inorganic constituents in soil samples, and organic and inorganic constituents in the surface water of a creek adjacent to the landfill, respectively. This assessment was conducted to provide environmental constituent data to Fort Gordon pursuant to requirements of the Resource Conservation and Recovery Act Part B Hazardous Waste Permit process. The passive soil-gas samplers deployed in the water-saturated hyporheic zone and flood plain of the creek adjacent to the former landfill indicated the presence of total petroleum hydrocarbon (TPH) and octane above method detection levels in groundwater beneath the creek bed and flood plain at all 12 soil-gas sampler locations. The TPH concentrations ranged from 51.4 to 81.4 micrograms per liter. Octane concentrations ranged from 1.78 to 2.63 micrograms per liter. These detections do not clearly identify specific source areas in the former landfill; moreover, detections of TPH and octane in a soil-gas sampler installed at a seep on the western bank of the creek indicated the potential for these constituents to be derived from source areas outside the estimated boundaries of the former landfill. A passive soil-gas sampler survey was conducted in the former landfill from June 30 to July 5, 2010, and involved 56 soil-gas samplers that were analyzed for petroleum and halogenated compounds not classified as chemical agents or explosives. The TPH soil-gas mass exceeded 2.0 micrograms in 21 samplers. Most noticeable are the two sites with TPH detections which are located in and near the hyporheic zone and are likely to affect

  8. Top Soils Geochemical and Radioactivity Survey of Naples (Italy) Metropolitan.

    Somma, R.; De Vivo, B.; Cicchella, D.

    2001-05-01

    The metropolitan area of Naples due to intense human activities is an emblematic area affected by various environmental pollution of soils and waters in addition to hydrogeological volcanic, seismic and bradyseismic hazards. The geology of the area is prevailing represented by volcanics erupted, from the Upper Pleistocene to Recent by Mt. Somma-Vesuvius on the east and the Campi Flegrei fields on the west. The morphology of the metropolitan area of Naples city can be subdivided in flat areas, constituted by reworked pyroclastic terrains, and by hills originated by the overlapping of different welded pyroclastic flows (i.e.: Campanian Ignimbrite and Neapoletan Yellow Tuff) intercalated with pyroclastic deposits of different origins (i.e.: Campi Flegrei, Mt. Somma-Vesuvius, Ischia) and ages. In order to compile a multi-element baseline geochemical and radioactivity mapping of the metropolitan area of the Napoli we have sampled for this study, in situ top soil and imported filling material (mainly soil, volcanic ash, pumice and scoriae). The sampling and radioactivity survey has been carried out on about 200 sampling sites covering an area of about 150 Km2, with a grid of 0.5 x 0.5 km in the urbanised downtown and 1 km x 1 km in the sub urban areas. In each site has been determined a radioactivity by a Scintrex GRS-500 at different emission spectra as total radioactivity (> 0.08 MeV and > 0.40 MeV), 238U (at 1.76 MeV mostly from 214Bi), 232Th (at 2.6 MeV mostly from 208Tl) and 40K (at 1.46 MeV mostly for 40K). The range of values of in situ soils are as follow for the in situ soils (Total radioactivity: 1327- 360 and 114- 47; 238U: 2.6- 1.3; 40K: 8.1- 3.1; 232U: 0.5- 0.1). Analyses of major, metallic elements and pH of each soil sample are in progress, while Pb isotopes compositions, for a selected number of samples, will be determined to discriminate the natural (geogenic) from the anthropogenic components in the soils by versus the anthropogenetic origin. The data

  9. Ground-truthing predicted indoor radon concentrations by using soil-gas radon measurements

    Reimer, G.M.

    2001-01-01

    Predicting indoor radon potential has gained in importance even as the national radon programs began to wane. A cooperative study to produce radon potential maps was conducted by the Environmental Protection Agency (EPA), U.S. Geological Survey (USGS), Department of Energy (DOE), and Lawrence Berkeley Laboratory (LBL) with the latter taking the lead role. A county-wide predictive model based dominantly on the National Uranium Resource Evaluation (NURE) aerorad data and secondly on geology, both small-scale data bases was developed. However, that model breaks down in counties of complex geology and does not provide a means to evaluate the potential of an individual home or building site. Soil-gas radon measurements on a large scale are currently shown to provide information for estimating radon potential at individual sites sort out the complex geology so that the small-scale prediction index can be validated. An example from Frederick County, Maryland indicates a positive correlation between indoor measurements and soil-gas data. The method does not rely on a single measurement, but a series that incorporate seasonal and meteorological considerations. (author)

  10. Modelling the relationship between soil color and particle size for soil survey in Ferralsol environments

    B. Kone

    2009-05-01

    Full Text Available Soil texture is an important property for evaluating its inherent fertility especially by using pedo-transfers functions requiring particle size data. However, there is no existing quantitative method for in situ estimation of soil particle size, delaying judgement of soil chemical properties in the field. For this purpose, laboratory particle size analyses of 1028 samples from 281 Ferralsol profiles, located between latitudes 7º N and 10º N in Côte d’Ivoire and their respective colour notation by Munsell chart were used to generate prediction models. Multiple Linear Regression Analysis by Group was processed to identify clay, sand and silt contents in the soil based on color hue (2.5YR, 5YR, 7.5YR, and 10YR and Chroma (1, 2, 3, 4, 5, 6, 7, 8. The evaluation was conducted for each horizon coded as H1 (0-20 cm, H2 (20-60 cm, H3 (60-80 cm and H4 (80-150 cm and used as grouping variables. Highly significant (P< 0.001 models were identified for clay and sand. These models were used to estimate successfully clay and sand contents for other Ferralsol samples by comparing calculated and measured mean using the null hypothesis of difference and Tukey’s tests. They were accurate for at all depths, except 80 - 150 cm, for sand in 10YR soils. The method was deemed appropriate for in situ estimation of soil particle size contents in Ferralsol environment for improving reconnaissance agricultural soil surveys.

  11. Level of carbon dioxide diffuse degassing from the ground of Vesuvio: comparison between extensive surveys and inferences on the gas source

    Domenico Granieri; Maria Luisa Carapezza; Rosario Avino; Stefano Caliro; Carlo Cardellini; Giovanni Chiodini; Marco Donnini; Carmine Minopoli; Massimo Ranaldi; Tullio Ricci; Luca Tarchini

    2013-01-01

    An extensive campaign of diffuse CO2 soil flux was carried out at the cone of Vesuvio in October 2006 with two main objectives: 1) to provide an estimation of CO2 diffusely discharged through the soils in the summit area and 2) to evidence those sectors of the volcano where structural and morphological conditions could favour the gas output. The survey consisted of 502 measurements of soil CO2 flux homogenously distributed over an area of about 1.8 km2. Results of this survey were compared wi...

  12. 222Rn flux and soil air concentration profiles in West-Germany. Soil 222Rn as tracer for gas transport in the unsaturated soil zone

    Doerr, H.; Muennich, K.O.

    1990-01-01

    Measurements of the 222 Rn activity concentration profile in the soil and the 222 Rn flux in West-Germany are presented. The spatial pattern of the 222 Rn flux depends more on soil type than on the 226 Ra activity of the soil material. The average 222 Rn flux from sandy soils is 1000-2000 dpm m -2 h -1 and 4000-6000 dpm m -2 h -1 froam loamy and clayey soils. Weekly 222 Rn flux measurements during a period of 1 year at a sandy site show no significant temporal variations. At a clayey site, the 222 Rn flux tends to be higher in summer than in winter. The permeability coefficient P Rn , obtained from simultaneous 222 Rn flux and concentration profile measurements in various soils, can be expressed as a function of the soil parameters total porosity ε 0 , soil moisture F, tortuosity k and the molecular diffusion coefficient D 0 of 222 Rn in air: P = D 0 ((ε 0 -F)/k-const.). The flux of any other gas into or out of the soil can thus be calculated from its measured concentration profile in the soil and from the 222 Rn permeability coefficient, replacing the molecular diffusion coefficient of 222 Rn by that of the specific gas under consideration. As an example, this method of flux determination is demonstrated for the soil CO 2 flux to the atmosphere and for the flux of atmospheric CH 4 into the soil. (author) 14 refs

  13. Maxwell's Law Based Models for Liquid and Gas Phase Diffusivities in Variably-Saturated Soil

    Mamamoto, Shoichiro; Møldrup, Per; Kawamoto, Ken

    2012-01-01

    -s,D-l). Different percolation threshold terms adopted from recent studies for gas (D-s,D-g) and solute (D-s,D-l) diffusion were applied. For gas diffusion, epsilon(th) was a function of bulk density (total porosity), while for solute diffusion theta(th) was best described by volumetric content of finer soil...... particles (clay and organic matter), FINESvol. The resulting LIquid and GAs diffusivity and tortuosity (LIGA) models were tested against D-s,D-g and D-s,D-l data for differently-textured soils and performed well against the measured data across soil types. A sensitivity analysis using the new Maxwell's Law...... based LIGA models implied that the liquid phase but not the gaseous-phase tortuosity was controlled by soil type. The analyses also suggested very different pathways and fluid-phase connectivity for gas and solute diffusion in unsaturated soil...

  14. Analysis of problems and failures in the measurement of soil-gas radon concentration.

    Neznal, Martin; Neznal, Matěj

    2014-07-01

    Long-term experience in the field of soil-gas radon concentration measurements allows to describe and explain the most frequent causes of failures, which can appear in practice when various types of measurement methods and soil-gas sampling techniques are used. The concept of minimal sampling depth, which depends on the volume of the soil-gas sample and on the soil properties, is shown in detail. Consideration of minimal sampling depth at the time of measurement planning allows to avoid the most common mistakes. The ways how to identify influencing parameters, how to avoid a dilution of soil-gas samples by the atmospheric air, as well as how to recognise inappropriate sampling methods are discussed. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

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

    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...

  16. Annual survey on the natural gas market: 2008 main results

    2009-09-01

    This document presents and briefly comments the main data of the natural gas market in France in 2008: gas production, gas transit (entry points receiving gas from various origins and export points to Spain and Switzerland), gas storage, gas distribution, gas sales in the different French regions and to different kinds of customers or industries

  17. Constitutive modelling of the undrained shear strength of fine grained soils containing gas

    Grozic, J.L.H. [Calgary Univ., AB (Canada); Nadim, F.; Kvalstad, T.J. [Norwegian Geotechnical Inst., Oslo (Norway)

    2002-07-01

    The behaviour of fine grained gassy soils was studied in order to develop a technique to quantitatively evaluate geohazards. Gas can occur in seabeds either in solution in pore water, undissolved in the form of gas filled voids, or as gas hydrates. In offshore soils, the degree of saturation is generally greater than 90 per cent, resulting in a soil structure with a continuous water phase and a discontinuous gas phase. The presence of methane gas will impact the strength of the soil, which alters its resistance to submarine sliding. This paper presents a constitutive model for determining the undrained shear strength of fine-grained gassy soils to assess the stability of deep water marine slopes for offshore developments. Methane gas is shown to have a beneficial effect on the soil strength in compressive loading, but the peak strength is achieved at larger deformations. The increased strength is a result of compression and solution gas which cause partial drainage and reduced pore pressures. The undrained shear strength of gassy soils was shown to increase with increasing initial consolidation stress, increasing volumetric coefficient of solubility, and increasing initial void ratio. 9 refs., 3 tabs., 6 figs.

  18. Soil gas anomalies along the Watukosek fault system, East Java, Indonesia

    Sciarra, A.; Ruggiero, L.; Bigi, S.; Mazzini, A.

    2017-12-01

    Two soil gas surveys were carried out in the Sidoarjo district (East Java, Indonesia) to investigate the gas leaking properties along fractured zones that coincide with a strike-slip system in NE Java, the Watukosek Fault System. This structure has been the focus of attention since the beginning of the spectacular Lusi mud eruption on the 29th May 2006. This fault system appear to be a sinistral strike-slip system that originates from the Arjuno-Welirang volcanic complex, intersects the active Lusi eruption site displaying a system of antithetic faults, and extends towards the NE of Java where mud volcanic structures reside. In the Lusi region we completed two geochemical surveys (222Rn and 220Rn activity, CO2 and CH4 flux and concentration) along four profiles crossing the Watukosek fault system. In May 2015 two profiles ( 1.2 km long) were performed inside the 7 km2 embankment area framing the erupted mud breccia zone and across regions characterized by intense fracturing and surface deformation. In April 2017 two additional profiles ( 4 km long) were carried out in the northern and southern part outside the Lusi embankment mud eruption area, intersecting the direction of main Watukosek fault system. All the profiles highlight that the fractured zones have the highest 222Rn activity, CO2 and CH4 flux and concentration values. The relationship existing among the measured parameters suggest that the Watukosek fault system acts as a preferential pathway for active rise of deep fluids. In addition the longer profiles outside the embankment show very high average values of CO2 (5 - 8 %,v/v) and 222Rn (17 - 11.5 kBq/m3), while soil gas collected along the profiles inside the Lusi mud eruption are CH4-dominant (up to 4.5%,v/v).This suggests that inside the embankment area (i.e. covered by tens of meters thick deposits of erupted mud breccia) the seepage is overall methane-dominated. This is likely the result of microbial reactions ongoing in the organic-rich sediments

  19. Regional quality control survey of blood-gas analysis.

    Minty, B D; Nunn, J F

    1977-09-01

    We undertook an external quality control survey of blood-gas analysis in 16 laboratories at 13 hospitals. All samples were prepared in the laboratories under investigation by equilibration of blood or serum with gas mixtures of known composition. pH of serum was measured with no significant bias but with an SD of random error 0.026 pH units, which was almost twice the SD of the reference range (0.015). An acceptable random error (half SD of reference range) was not obtained in a longitudinal internal quality control suvey although there were acceptable results for buffer pH in both field and internal surveys. Blood PO2 was measured with no significant bias but with SD of random error 1.38 kPa which reduced to 0.72 kPa by excluding one egregious result. The latter value was just over half of the SD of the reference range (1.2 kPa). PCO2 of blood was also measured without significant bias but with a much smaller SD of random error of 0.28 kPa (by excluding one egregious result), which was again just over half the SD of the reference range (0.51 kPa). Measurements of blood PO2 and PCO2 seem generally acceptable in relation to their respective reference ranges but measurements of pH were unsatisfactory in both internal and external trials.

  20. Annual survey 2013 - Natural gas in the World 2013

    2013-01-01

    The 2013 Edition of 'Natural Gas in the World' by CEDIGAZ is built on CEDIGAZ's unique natural gas statistical database. This 170-page study, published since 1983, provides an in-depth analysis of the latest developments in the gas markets along with the most complete set of statistical data on the whole gas chain covering close to 130 countries. Topics covered by Natural Gas in the World 2013 include: proved natural gas reserves; unconventional gas status in the world; gross and marketed natural gas production; the international gas trade; existing and planned underground gas storage facilities in the world; natural gas consumption; natural gas prices

  1. The Effect of Thermal Convection on Earth-Atmosphere CO2 Gas Exchange in Aggregated Soil

    Ganot, Y.; Weisbrod, N.; Dragila, M. I.

    2011-12-01

    Gas transport in soils and surface-atmosphere gas exchange are important processes that affect different aspects of soil science such as soil aeration, nutrient bio-availability, sorption kinetics, soil and groundwater pollution and soil remediation. Diffusion and convection are the two main mechanisms that affect gas transport, fate and emissions in the soils and in the upper vadose zone. In this work we studied CO2 soil-atmosphere gas exchange under both day-time and night-time conditions, focusing on the impact of thermal convection (TCV) during the night. Experiments were performed in a climate-controlled laboratory. One meter long columns were packed with matrix of different grain size (sand, gravel and soil aggregates). Air with 2000 ppm CO2 was injected into the bottom of the columns and CO2 concentration within the columns was continuously monitored by an Infra Red Gas Analyzer. Two scenarios were compared for each soil: (1) isothermal conditions, representing day time conditions; and (2) thermal gradient conditions, i.e., atmosphere colder than the soil, representing night time conditions. Our results show that under isothermal conditions, diffusion is the major mechanism for surface-atmosphere gas exchange for all grain sizes; while under night time conditions the prevailing mechanism is dependent on the air permeability of the matrix: for sand and gravel it is diffusion, and for soil aggregates it is TCV. Calculated CO2 flux for the soil aggregates column shows that the TCV flux was three orders of magnitude higher than the diffusive flux.

  2. Soil greenhouse gas fluxes from different tree species on Taihang Mountain, North China

    Liu, X. P.; Zhang, W. J.; Hu, C. S.; Tang, X. G.

    2014-03-01

    The objectives of this study were to investigate seasonal variation of greenhouse gas fluxes from soils on sites dominated by plantation (Robinia pseudoacacia, Punica granatum, and Ziziphus jujube) and natural regenerated forests (Vitex negundo var. heterophylla, Leptodermis oblonga, and Bothriochloa ischcemum), and to identify how tree species, litter exclusion, and soil properties (soil temperature, soil moisture, soil organic carbon, total N, soil bulk density, and soil pH) explained the temporal and spatial variation in soil greenhouse gas fluxes. Fluxes of greenhouse gases were measured using static chamber and gas chromatography techniques. Six static chambers were randomly installed in each tree species. Three chambers were randomly designated to measure the impacts of surface litter exclusion, and the remaining three were used as a control. Field measurements were conducted biweekly from May 2010 to April 2012. Soil CO2 emissions from all tree species were significantly affected by soil temperature, soil moisture, and their interaction. Driven by the seasonality of temperature and precipitation, soil CO2 emissions demonstrated a clear seasonal pattern, with fluxes significantly higher during the rainy season than during the dry season. Soil CH4 and N2O fluxes were not significantly correlated with soil temperature, soil moisture, or their interaction, and no significant seasonal differences were detected. Soil organic carbon and total N were significantly positively correlated with CO2 and N2O fluxes. Soil bulk density was significantly negatively correlated with CO2 and N2O fluxes. Soil pH was not correlated with CO2 and N2O emissions. Soil CH4 fluxes did not display pronounced dependency on soil organic carbon, total N, soil bulk density, and soil pH. Removal of surface litter significantly decreased in CO2 emissions and CH4 uptakes. Soils in six tree species acted as sinks for atmospheric CH4. With the exception of Ziziphus jujube, soils in all tree

  3. ALMA Survey of Lupus Protoplanetary Disks. II. Gas Disk Radii

    Ansdell, M.; Williams, J. P.; Trapman, L.; van Terwisga, S. E.; Facchini, S.; Manara, C. F.; van der Marel, N.; Miotello, A.; Tazzari, M.; Hogerheijde, M.; Guidi, G.; Testi, L.; van Dishoeck, E. F.

    2018-05-01

    We present Atacama Large Millimeter/Sub-Millimeter Array (ALMA) Band 6 observations of a complete sample of protoplanetary disks in the young (∼1–3 Myr) Lupus star-forming region, covering the 1.33 mm continuum and the 12CO, 13CO, and C18O J = 2–1 lines. The spatial resolution is ∼0.″25 with a medium 3σ continuum sensitivity of 0.30 mJy, corresponding to M dust ∼ 0.2 M ⊕. We apply Keplerian masking to enhance the signal-to-noise ratios of our 12CO zero-moment maps, enabling measurements of gas disk radii for 22 Lupus disks; we find that gas disks are universally larger than millimeter dust disks by a factor of two on average, likely due to a combination of the optically thick gas emission and the growth and inward drift of the dust. Using the gas disk radii, we calculate the dimensionless viscosity parameter, α visc, finding a broad distribution and no correlations with other disk or stellar parameters, suggesting that viscous processes have not yet established quasi-steady states in Lupus disks. By combining our 1.33 mm continuum fluxes with our previous 890 μm continuum observations, we also calculate the millimeter spectral index, α mm, for 70 Lupus disks; we find an anticorrelation between α mm and millimeter flux for low-mass disks (M dust ≲ 5), followed by a flattening as disks approach α mm ≈ 2, which could indicate faster grain growth in higher-mass disks, but may also reflect their larger optically thick components. In sum, this work demonstrates the continuous stream of new insights into disk evolution and planet formation that can be gleaned from unbiased ALMA disk surveys.

  4. Effects of soil rewetting and thawing on soil gas fluxes: a review of current literature and suggestions for future research

    D.-G. Kim

    2012-07-01

    Full Text Available The rewetting of dry soils and the thawing of frozen soils are short-term, transitional phenomena in terms of hydrology and the thermodynamics of soil systems. The impact of these short-term phenomena on larger scale ecosystem fluxes is increasingly recognized, and a growing number of studies show that these events affect fluxes of soil gases such as carbon dioxide (CO2, methane (CH4, nitrous oxide (N2O, ammonia (NH3 and nitric oxide (NO. Global climate models predict that future climatic change is likely to alter the frequency and intensity of drying-rewetting events and thawing of frozen soils. These future scenarios highlight the importance of understanding how rewetting and thawing will influence dynamics of these soil gases. This study summarizes findings using a new database containing 338 studies conducted from 1956 to 2011, and highlights open research questions. The database revealed conflicting results following rewetting and thawing in various terrestrial ecosystems and among soil gases, ranging from large increases in fluxes to non-significant changes. Studies reporting lower gas fluxes before rewetting tended to find higher post-rewetting fluxes for CO2, N2O and NO; in addition, increases in N2O flux following thawing were greater in warmer climate regions. We discuss possible mechanisms and controls that regulate flux responses, and recommend that a high temporal resolution of flux measurements is critical to capture rapid changes in gas fluxes after these soil perturbations. Finally, we propose that future studies should investigate the interactions between biological (i.e., microbial community and gas production and physical (i.e., porosity, diffusivity, dissolution changes in soil gas fluxes, apply techniques to capture rapid changes (i.e., automated measurements, and explore synergistic experimental and modelling approaches.

  5. Annual survey of the natural gas market: 2010 results

    Welter-Nicol, Cecile

    2011-12-01

    This document presents and briefly comments the main data of the natural gas market in France in 2010: gas production (only 2 pc of supplies), gas transit evolutions since 2007 (entry points receiving gas from various origins and export points to Spain and Switzerland), outlines the increase of imports from Norway, comments gas storage capacities, the evolution of gas distribution in France, the evolution of gas consumption, and gas sales in the different French regions and to different kinds of customers or industries

  6. Moving beyond the udorthent - a proposed protocol for surveying urban soils to service data needs for contemporary urban ecosystem management

    County-level, Order 2 soil surveys have been used for decades to illustrate the spatial distribution of soils and communicate the utility and limitations of soil series. For the vast majority of these soil surveys, however, there is a distinct lack of resolution of soil series an...

  7. Delignification and Enhanced Gas Release from Soil Containing Lignocellulose by Treatment with Bacterial Lignin Degraders.

    Rashid, Goran M M; Duran-Pena, Maria Jesus; Rahmanpour, Rahman; Sapsford, Devin; Bugg, Timothy D H

    2017-04-10

    The aim of the study was to isolate bacterial lignin-degrading bacteria from municipal solid waste soil, and to investigate whether they could be used to delignify lignocellulose-containing soil, and enhance methane release. A set of 20 bacterial lignin degraders, including 11 new isolates from municipal solid waste soil, were tested for delignification and phenol release in soil containing 1% pine lignocellulose. A group of 7 strains were then tested for enhancement of gas release from soil containing 1% lignocellulose in small-scale column tests. Using an aerobic pre-treatment, aerobic strains such as Pseudomonas putida showed enhanced gas release from the treated sample, but four bacterial isolates showed 5-10 fold enhancement in gas release in an in situ experiment under microanaerobic conditions: Agrobacterium sp., Lysinibacillus sphaericus, Comamonas testosteroni, and Enterobacter sp.. The results show that facultative anaerobic bacterial lignin degraders found in landfill soil can be used for in situ delignification and enhanced gas release in soil containing lignocellulose. The study demonstrates the feasibility of using an in situ bacterial treatment to enhance gas release and resource recovery from landfill soil containing lignocellulosic waste. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  8. Model analysis of the influence of gas diffusivity in soil on CO and H2 uptake

    Yonemura, S.; Yokozawa, M.; Kawashima, S.; Tsuruta, H.

    2000-01-01

    CO and H 2 uptake by soil was studied as a diffusion process. A diffusion model was used to determine how the surface fluxes (net deposition velocities) were controlled by in-situ microbial uptake rates and soil gas diffusivity calculated from the 3-phase system (solid, liquid, gas) in the soil. Analytical solutions of the diffusion model assuming vertical uniformity of soil properties showed that physical properties such as air-filled porosity and soil gas diffusivity were more important in the uptake process than in the emission process. To incorporate the distribution of in-situ microbial uptake, we used a 2-layer model incorporating 'a microbiologically inactive layer and an active layer' as suggested from experimental results. By numerical simulation using the 2-layer model, we estimated the effect of several factors on deposition velocities. The variations in soil gas diffusivity due to physical properties, i.e., soil moisture and air-filled porosity, as well as to the depth of the inactive layer and in-situ microbial uptake, were found to be important in controlling deposition velocities. This result shows that the diffusion process in soil is critically important for CO and H 2 uptake by soil, at least in soils with higher in-situ uptake rates and/or with large variation in soil moisture. Similar uptake rates and the difference in deposition velocity between CO and H 2 may be attributable to differences in CO and H 2 molecular diffusivity. The inactive layer is resistant to diffusion and creates uptake limits in CO and H 2 by soil. The coupling of high temperature and a thick inactive layer, common in arid soils, markedly lowers net CO deposition velocity. The temperature for maximum uptake of CO changes with depth of the inactive layer

  9. Soil gas and radon entry into a simple test structure: Comparison of experimental and modelling results

    Andersen, C.E.; Søgaard-Hansen, J.; Majborn, B.

    1994-01-01

    A radon test structure has been established at a field site at Riso National Laboratory. Measurements have been made of soil gas entry rates, pressure couplings and radon depletion. The experimental results have been compared with results obtained from measured soil parameters and a two......-dimensional steady-state numerical model of Darcy flow and combined diffusive and advective transport of radon. For most probe locations, the calculated values of the pressure couplings and the radon depletion agree well with the measured values, thus verifying important elements of the Darcy flow approximation......, and the ability of the model to treat combined diffusive and advective transport of radon. However, the model gives an underestimation of the soil gas entry rate. Even if it is assumed that the soil has a permeability equal to the highest of the measured values, the model underestimates the soil gas entry rate...

  10. A Global Database of Gas Fluxes from Soils after Rewetting or Thawing, Version 1.0

    National Aeronautics and Space Administration — This database contains information compiled from published studies on gas flux from soil following rewetting or thawing. The resulting database includes 222 field...

  11. Soil gas radon–thoron monitoring in Dharamsala area of north-west ...

    2National Center for Research on Earthquake Engineering, NARL, Taipei 106, Taiwan. ... The study described here is based on the measurements of soil gas radon–thoron concentrations performed ..... Himachal Pradesh, India; Nat. Hazards ...

  12. Assessment of groundwater, soil-gas, and soil contamination at the Vietnam Armor Training Facility, Fort Gordon, Georgia, 2009-2011

    Guimaraes, Wladmir B.; Falls, W. Fred; Caldwell, Andral W.; Ratliff, W. Hagan; Wellborn, John B.; Landmeyer, James E.

    2012-01-01

    The U.S. Geological Survey, in cooperation with the U.S. Department of the Army Environmental and Natural Resources Management Office of the U.S. Army Signal Center and Fort Gordon, Georgia, assessed the groundwater, soil gas, and soil for contaminants at the Vietnam Armor Training Facility (VATF) at Fort Gordon, from October 2009 to September 2011. The assessment included the detection of organic compounds in the groundwater and soil gas, and inorganic compounds in the soil. In addition, organic contaminant assessment included organic compounds classified as explosives and chemical agents in selected areas. The assessment was conducted to provide environmental contamination data to the U.S. Army at Fort Gordon pursuant to requirements of the Resource Conservation and Recovery Act Part B Hazardous Waste Permit process. This report is a revision of "Assessment of soil-gas, surface-water, and soil contamination at the Vietnam Armor Training Facility, Fort Gordon, Georgia, 2009-2010," Open-File Report 2011-1200, and supersedes that report to include results of additional samples collected in July 2011. Four passive samplers were deployed in groundwater wells at the VATF in Fort Gordon. Total petroleum hydrocarbons and benzene and octane were detected above the method detection level at all four wells. The only other volatile organic compounds detected above their method detection level were undecane and pentadecane, which were detected in two of the four wells. Soil-gas samplers were deployed at 72 locations in a grid pattern across the VATF on June 3, 2010, and then later retrieved on June 9, 2010. Total petroleum hydrocarbons were detected in 71 of the 72 samplers (one sampler was destroyed in the field and not analyzed) at levels above the method detection level, and the combined mass of benzene, toluene, ethylbenzene, and total xylene (BTEX) was detected above the detection level in 31 of the 71 samplers that were analyzed. Other volatile organic compounds

  13. A Survey of Methods for Gas-Lift Optimization

    Kashif Rashid

    2012-01-01

    Full Text Available This paper presents a survey of methods and techniques developed for the solution of the continuous gas-lift optimization problem over the last two decades. These range from isolated single-well analysis all the way to real-time multivariate optimization schemes encompassing all wells in a field. While some methods are clearly limited due to their neglect of treating the effects of inter-dependent wells with common flow lines, other methods are limited due to the efficacy and quality of the solution obtained when dealing with large-scale networks comprising hundreds of difficult to produce wells. The aim of this paper is to provide an insight into the approaches developed and to highlight the challenges that remain.

  14. Effect of air turbulence on gas transport in soil; comparison of approaches

    Pourbakhtiar, Alireza; Papadikis, Konstantinos; Poulsen, Tjalfe; Bridge, Jonathan; Wilkinson, Stephen

    2017-04-01

    Greenhouse gases are playing the key role in global warming. Soil is a source of greenhouse gases such as methane (CH4). Radon (Rn) which is a radioactive gas can emit form subsurface into the atmosphere and leads to health concerns in urban areas. Temperature, humidity, air pressure and vegetation of soil can affect gas emissions inside soil (Oertel et al., 2016). It's shown in many cases that wind induced fluctuations is an important factor in transport of gas through soil and other porous media. An example is: landfill gas emissions (Poulsen et al., 2001). We applied an experimental equipment for measuring controlled air turbulence on gas transport in soil in relation to the depth of sample. Two approaches for measurement of effect of wind turbulence on gas transport were applied and compared. Experiments were carried out with diffusion of CO2 and air as tracer gases with average vertical wind speeds of 0 to 0.83 m s-1. In approach A, Six different sample thicknesses from 5 to 30 cm were selected and total of 4 different wind conditions with different speed and fluctuations were applied. In approach B, a sample with constant depth was used. Five oxygen sensors were places inside sample at different depths. Total of 111 experiments were carried out. Gas transport is described by advection-dispersion equation. Gas transport is quantified as a dispersion coefficient. Oxygen breakthrough curves as a function of distance to the surface of the sample exposed to wind were derived numerically with an explicit forward time, central space finite-difference based model to evaluate gas transport. We showed that wind turbulence-induced fluctuations is an important factor in gas transport that can increase gas transport with average of 45 times more than molecular diffusion under zero wind condition. Comparison of two strategies for experiments, indicated that, constant deep samples (Approach B) are more reliable for measurement of gas transport under influence of wind

  15. Effect of freeze-thaw cycles on greenhouse gas fluxes from peat soils

    Oh, H. D.; Rezanezhad, F.; Markelov, I.; McCarter, C. P. R.; Van Cappellen, P.

    2017-12-01

    The ongoing displacement of climate zones by global warming is increasing the frequency and intensity of freeze-thaw cycles in middle and high latitude regions, many of which are dominated by organic soils such as peat. Repeated freezing and thawing of soils changes their physical properties, geochemistry, and microbial community structure, which together govern the biogeochemical cycling of carbon and nutrients. In this presentation, we focus on how freeze-thaw cycles influence greenhouse gas fluxes from peat using a newly developed experimental soil column system that simulates realistic soil temperature profiles during freeze-thaw cycles. We measured the surface and subsurface changes to gas and aqueous phase chemistry to delineate the diffusion pathways and quantify soil greenhouse gas fluxes during freeze-thaw cycles using sulfur hexafluoride (SF6) as a conservative tracer. Three peat columns were assembled inside a temperature controlled chamber with different soil structures. All three columns were packed with 40 cm of undisturbed, slightly decomposed peat, where the soil of two columns had an additional 10 cm layer on top (one with loose Sphagnum moss and one with an impermeable plug). The results indicate that the release of SF6 and CO2 gas from the soil surface was influenced by the recurrent development of a physical ice barrier, which prevented gas exchange between the soil and atmosphere during freezing conditions. With the onset of thawing a pulse of SF6 and CO2 occurred, resulting in a flux of 3.24 and 2095.52 µmol/m2h, respectively, due to the build-up of gases in the liquid-phase pore space during freezing. Additionally, we developed a model to determine the specific diffusion coefficients for each peat column. These data allow us to better predict how increased frequency and intensity of freeze-thaw cycles will affect greenhouse gas emissions in northern peat soils.

  16. LBA-ECO TG-07 Soil Trace Gas Flux and Root Mortality, Tapajos National Forest

    R.K. Varner; M.M. Keller

    2009-01-01

    This data set reports the results of an experiment that tested the short-term effects of root mortality on the soil-atmosphere fluxes of nitrous oxide, nitric oxide, methane, and carbon dioxide in a tropical evergreen forest. Weekly trace gas fluxes are provided for treatment and control plots on sand and clay tropical forest soils in two comma separated ASCII files....

  17. 7 CFR 600.9 - Major land resource area soil survey offices.

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Major land resource area soil survey offices. 600.9 Section 600.9 Agriculture Regulations of the Department of Agriculture (Continued) NATURAL RESOURCES CONSERVATION SERVICE, DEPARTMENT OF AGRICULTURE GENERAL ORGANIZATION § 600.9 Major land resource area soil survey offices. The United States is divide...

  18. A knowledge - based system to assist in the design of soil survey schemes

    Domburg, P.

    1994-01-01

    Soil survey information with quantified accuracy is relevant to decisions on land use and environmental problems. To obtain such information statistical strategies should be used for collecting and analysing data. A survey project based on a statistical sampling strategy requires a soil

  19. Effect of Aggregate Structure on VOC Gas Adsorption onto Volcanic Ash Soil

    濱本, 昌一郎

    2008-01-01

    The understanding of the gaseous adsorption process and the parameters of volatile organic compounds such as organic solvents or fuels onto soils is very important in the analysis of the transport or fate of these chemicals in soils. Batch adsorption experiments with six different treatments were conducted to determine the adsorption of isohexane, a gaseous aliphatic, onto volcanic ash soil (Tachikawa loam). The measured gas adsorption coefficient for samples of Tachikawa loam used in the fir...

  20. {sup 222}Rn and CO{sub 2} soil-gas geochemical characterization of thermally altered clays at Orciatico (Tuscany, Central Italy)

    Voltattorni, N., E-mail: nunzia.voltattorni@ingv.it [Istituto Nazionale di Geofisica e Vulcanologia, Via di Vigna Murata 605, 00143 Rome (Italy); Lombardi, S. [Earth Science Department, University ' La Sapienza' , Piazzale A. Moro 5, 00185 Rome (Italy); Rizzo, S. [Via Tito, 1/A, 00061 Anguillara Sabazia, Rome (Italy)

    2010-08-15

    Research highlights: {yields} Soil-gas technique is applied to study gas permeability of Orciatico clay units. {yields} Clay permeability depends on thermal and mechanical alteration degree. {yields} Soil-gas distributions are due to shallow fracturing of clays. {yields} Rn and CO{sub 2} soil-gas anomalies highlight secondary permeability in clay sequence. {yields} Soil-gas results are supported by detailed geoelectrical surveys. - Abstract: The physical properties of clay allow argillaceous formations to be considered geological barriers to radionuclide migration in high-level radioactive-waste isolation systems. As laboratory simulations are short term and numerical models always involve assumptions and simplifications of the natural system, natural analogues are extremely attractive surrogates for the study of long-term isolation. The clays of the Orciatico area (Tuscany, Central Italy), which were thermally altered via the intrusion of an alkali-trachyte laccolith, represent an interesting natural model of a heat source which acted on argillaceous materials. The study of this natural analogue was performed through detailed geoelectrical and soil-gas surveys to define both the geometry of the intrusive body and the gas permeability of a clay unit characterized by different degrees of thermal alteration. The results of this study show that gas permeability is increased in the clay sequences subjected to greater heat input from the emplacement of the Orciatico intrusion, despite the lack of apparent mineral and geotechnical variations. These results, which take into consideration long time periods in a natural, large-scale geological system, may have important implications for the long-term safety of underground storage of nuclear waste in clay formations.

  1. Gas Hydrates | Alaska Division of Geological & Geophysical Surveys

    Preliminary Report - Cascadia Margin Gas Hydrates, Volume 204 Initial Report Mallik 2002 GSC Bulletin 585 : Scientific results from the Mallik 2002 gas hydrate production well program Offshore gas hydrate sample

  2. Hydro-geomechanical behaviour of gas-hydrate bearing soils during gas production through depressurization and CO2 injection

    Deusner, C.; Gupta, S.; Kossel, E.; Bigalke, N.; Haeckel, M.

    2015-12-01

    Results from recent field trials suggest that natural gas could be produced from marine gas hydrate reservoirs at compatible yields and rates. It appears, from a current perspective, that gas production would essentially be based on depressurization and, when facing suitable conditions, be assisted by local thermal stimulation or gas hydrate conversion after injection of CO2-rich fluids. Both field trials, onshore in the Alaska permafrost and in the Nankai Trough offshore Japan, were accompanied by different technical issues, the most striking problems resulting from un-predicted geomechanical behaviour, sediment destabilization and catastrophic sand production. So far, there is a lack of experimental data which could help to understand relevant mechanisms and triggers for potential soil failure in gas hydrate production, to guide model development for simulation of soil behaviour in large-scale production, and to identify processes which drive or, further, mitigate sand production. We use high-pressure flow-through systems in combination with different online and in situ monitoring tools (e.g. Raman microscopy, MRI) to simulate relevant gas hydrate production scenarios. Key components for soil mechanical studies are triaxial systems with ERT (Electric resistivity tomography) and high-resolution local strain analysis. Sand production control and management is studied in a novel hollow-cylinder-type triaxial setup with a miniaturized borehole which allows fluid and particle transport at different fluid injection and flow conditions. Further, the development of a large-scale high-pressure flow-through triaxial test system equipped with μ-CT is ongoing. We will present results from high-pressure flow-through experiments on gas production through depressurization and injection of CO2-rich fluids. Experimental data are used to develop and parametrize numerical models which can simulate coupled process dynamics during gas-hydrate formation and gas production.

  3. Use of Flue Gas Desulfurization (FGD) Gypsum as a Heavy Metal Stabilizer in Contaminated Soils

    Flue Gas Desulfurization (FGD) gypsum is a synthetic by-product generated from the flue gas desulfurization process in coal power plants. It has several beneficial applications such as an ingredient in cement production, wallboard production and in agricultural practice as a soil...

  4. Persistent effects of subsoil compaction on pore size distribution and gas transport in a loamy soil

    Berisso, Feto Esimo; Schjønning, Per; Keller, T

    2012-01-01

    included four repeated wheelings with ∼10 Mg wheel loads. Water retention characteristics (WRC), air permeability (ka) and gas diffusivity (Ds/Do) were measured. A dual-porosity model fitted the WRC well, and there was a reduction in the volume of macropores >30 μm in compacted compared with control soil...... for all soil depths. Averaged for all sampling depths and also for some individual depths, both ka and Ds/Do were significantly reduced by compaction. Gas transport measurements showed that the experimental soil was poorly aerated, with local anoxic conditions at water regimes around field capacity in all...

  5. Freeze-Thaw Cycles and Soil Biogeochemistry: Implications for Greenhouse Gas emission

    Rezanezhad, F.; Milojevic, T.; Oh, D. H.; Parsons, C. T.; Smeaton, C. M.; Van Cappellen, P.

    2016-12-01

    Freeze-thaw cycles represent a major natural climate forcing acting on soils at middle and high latitudes. Repeated freezing and thawing of soils changes their physical properties, geochemistry, and microbial community structure, which together govern the biogeochemical cycling of carbon and nutrients. In this presentation, we focus on how freeze-thaw cycles regulate carbon and nitrogen cycling and how these transformations influence greenhouse gas (GHG) fluxes. We present a novel approach, which combines the acquisition of physical and chemical data in a newly developed experimental soil column system. This system simulates realistic soil temperature profiles during freeze-thaw cycles. A high-resolution, Multi-Fiber Optode (MuFO) microsensor technique was used to detect oxygen (O2) continuously in the column at multiple depths. Surface and subsurface changes to gas and aqueous phase chemistry were measured to delineate the pathways and quantify soil respiration rates during freeze-thaw cycles. The results indicate that the time-dependent release of GHG from the soil surface is influenced by a combination of two key factors. Firstly, fluctuations in temperature and O2 availability affect soil biogeochemical activity and GHG production. Secondly, the recurrent development of a physical ice barrier prevents exchange of gaseous compounds between the soil and atmosphere during freezing conditions; removal of this barrier during thaw conditions increases GHG fluxes. During freezing, O2 levels in the unsaturated zone decreased due to restricted gas exchange with the atmosphere. As the soil thawed, O2 penetrated deeper into the soil enhancing the aerobic mineralization of organic carbon and nitrogen. Additionally, with the onset of thawing a pulse of gas flux occurred, which is attributed to the build-up of respiratory gases in the pore space during freezing. The latter implies enhanced anaerobic respiration as O2 supply ceases when the upper soil layer freezes.

  6. The Spatial Variability of Soil Dehydrogenase Activity: A Survey in Urban Soils

    Kizilkaya, Ridvan; Aşkin, Tayfun

    2007-01-01

    Information on soil microorganisms and their activity used to determine microbiological characteristics are very important for soil quality and productivity. Studies of enzyme activities provide information on the biochemical processes occurring in soil. There is growing evidence that soil biological parameters may be potential and sensitive indicators of soil ecological conditions and soil management. Soil microbiological parameters may be evaluated statistically due to application of geosta...

  7. Level of carbon dioxide diffuse degassing from the ground of Vesuvio: comparison between extensive surveys and inferences on the gas source

    Granieri, D.; Carapezza, M. L.; Avino, R.; Caliro, S.; Cardellini, C.; Chiodini, G.; Donnini, M.; Minopoli, C.; Ranaldi, M.; Ricci, T.; Tarchini, L.

    2013-01-01

    An extensive campaign of diffuse CO2 soil flux was carried out at the cone of Vesuvio in October 2006 with two main objectives: 1) to provide an estimation of CO2 diffusely discharged through the soils in the summit area and 2) to evidence those sectors of the volcano where structural and morphological conditions could favour the gas output. The survey consisted of 502 measurements of soil CO2 flux homogenously distributed over an area of about 1.8 km2. Results of this surve...

  8. Effect of aggregate structure on VOC gas adsorption onto volcanic ash soil.

    Hamamoto, Shoichiro; Seki, Katsutoshi; Miyazaki, Tsuyoshi

    2009-07-15

    The understanding of the gaseous adsorption process and the parameters of volatile organic compounds such as organic solvents or fuels onto soils is very important in the analysis of the transport or fate of these chemicals in soils. Batch adsorption experiments with six different treatments were conducted to determine the adsorption of isohexane, a gaseous aliphatic, onto volcanic ash soil (Tachikawa loam). The measured gas adsorption coefficient for samples of Tachikawa loam used in the first three treatments, Control, AD (aggregate destroyed), and AD-OMR (aggregate destroyed and organic matter removed), implied that the aggregate structure of volcanic ash soil as well as organic matter strongly enhanced gas adsorption under the dry condition, whereas under the wet condition, the aggregate structure played an important role in gas adsorption regardless of the insolubility of isohexane. In the gas adsorption experiments for the last three treatments, soils were sieved in different sizes of mesh and were separated into three different aggregate or particle size fractions (2.0-1.0mm, 1.0-0.5mm, and less than 0.5mm). Tachikawa loam with a larger size fraction showed higher gas adsorption coefficient, suggesting the higher contributions of macroaggregates to isohexane gas adsorption under dry and wet conditions.

  9. Effect of leaking natural gas on soil and vegetation in urban areas

    Hoeks, J

    1972-01-01

    Leakage of natural gas from the gas distribution system affects the physical, chemical and biological processes in the soil. Particularly the microbial oxidation of methane is then of predominant importance for the composition of the soil gas phase. The rate of methane oxidation was measured under varying conditions of gas phase composition, temperature and nutrient supply. Computation models were evolved with which it is possible to calculate the effect of these and other factors on the distribution of methane, oxygen and carbon dioxide around a leak. Experiments with actual and artificial leaks as well as the calculations showed that the extent of the gas zone largely depends on the leakage rate, the depth of the groundwater table, the soil moisture content and the extent of the pavement. The soil temperature also proved to have a significant influence by its effect on the microbial methane oxidation. At low temperatures this microbial process is limited and consequently the anaerobic zone, which is invariably present in summer, may then disappear completely, thus making the probability of injury to vegetation negligible in winter. After repair of the leak the poor aeration conditions in the soil may persist for quite a long time. This is caused by the high consumption rate of oxygen required for the oxidation of organic substances and reduced anorganic compounds accumulated in the soil during gas leakage. The oxygen overdemand and the oxidation rate were determined for various gassed soils. Measures can be taken to accelerate soil recovery processes and to improve conditions for regeneration of injured trees and before planting new trees. Both experiments and calculations with computation models prove that installation of open ventilation channels is very effective, even if the leak cannot be immediately repaired. So ventilation channels can also be installed as preventive measure. 138 references.

  10. Refining soil survey information for a Dutch soil series using land use history

    Sonneveld, M.P.W.; Bouma, J.; Veldkamp, A.

    2002-01-01

    Differences in land-use history within soil series, although not influencing soil classification, lead to variability of non-diagnostic soil properties in soil databases. Regional studies that use soil databases are confronted with this considerable variability. This has, for example, been reported

  11. Rn, He and CO{sub 2} soil gas geochemistry for the study of active and inactive faults

    Lombardi, S. [Earth Science Department - University ' La Sapienza' , Piazzale A. Moro 5, 00185 Rome (Italy); Voltattorni, N., E-mail: nunzia.voltattorni@ingv.it [Istituto Nazionale di Geofisica e Vulcanologia, Via di Vigna Murata 605, 00143 Rome (Italy)

    2010-08-15

    Two Italian areas, characterized by different seismological histories, were investigated to enhance the basic knowledge of gas migration mechanisms during earthquakes. Sharp variations occur in the movement and concentration of some gaseous species due to the evolution of the local stress regime. The first area (Colpasquale) is located in the central Italian region of Marche and provided a good location to study gas migration in a seismically active region. The area was devastated by a sequence of shallow earthquakes over a 3 month-long period (September-December, 1997). The occurrence of this catastrophic event, as well as the long duration of the 'seismic sequence', presented a unique opportunity to study gas migration in a zone undergoing active displacement. Soil gas surveys were performed 1 day, 1 week, 1 year and 2 years after the main shock (Ms 5.6) in the Colpasquale area. In particular, results highlight a change in the Rn distribution during the three monitoring years indicating a variation of gas migration that may be linked to the evolution of the stress regime. The second study area is located in the Campidano Graben (southern part of Sardinia Island). This area is characterized by seismic quiescence, displaying an almost complete lack of historical earthquakes and instrumentally recorded seismicity. The consistently low values observed for all analyzed gases suggest that the studied area is likely characterized by sealed, non-active faults that prevent significant gas migration. The comparison of data from both studied areas indicate that soil gas geochemistry is useful to locate tectonic discontinuities even when they intersect non-cohesive clastic rocks near the surface and thus are not visible (i.e., 'blind faults').

  12. Soil arsenic surveys of New Orleans: localized hazards in children's play areas.

    Mielke, Howard W; Gonzales, Chris R; Cahn, Elise; Brumfield, Jessica; Powell, Eric T; Mielke, Paul W

    2010-10-01

    Arsenic (As) ranks first on the 2005 and 2007 hazardous substances priority lists compiled for the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). This study describes two New Orleans soil As surveys: (1) a survey of composite soil samples from 286 census tracts and (2) a field survey of soil As at 38 play areas associated with the presence of chromated-copper-arsenate (CCA)-treated wood on residential and public properties. The survey of metropolitan New Orleans soils revealed a median As content of 1.5 mg/kg (range New Orleans probably exists in play areas across the nation. These findings support a precautionary program for testing soils and wood for hazardous substances at all play areas intended for children.

  13. Offsetting global warming-induced elevated greenhouse gas emissions from an arable soil by biochar application.

    Bamminger, Chris; Poll, Christian; Marhan, Sven

    2018-01-01

    Global warming will likely enhance greenhouse gas (GHG) emissions from soils. Due to its slow decomposability, biochar is widely recognized as effective in long-term soil carbon (C) sequestration and in mitigation of soil GHG emissions. In a long-term soil warming experiment (+2.5 °C, since July 2008) we studied the effect of applying high-temperature Miscanthus biochar (0, 30 t/ha, since August 2013) on GHG emissions and their global warming potential (GWP) during 2 years in a temperate agroecosystem. Crop growth, physical and chemical soil properties, temperature sensitivity of soil respiration (R s ), and metabolic quotient (qCO 2 ) were investigated to yield further information about single effects of soil warming and biochar as well as on their interactions. Soil warming increased total CO 2 emissions by 28% over 2 years. The effect of warming on soil respiration did not level off as has often been observed in less intensively managed ecosystems. However, the temperature sensitivity of soil respiration was not affected by warming. Overall, biochar had no effect on most of the measured parameters, suggesting its high degradation stability and its low influence on microbial C cycling even under elevated soil temperatures. In contrast, biochar × warming interactions led to higher total N 2 O emissions, possibly due to accelerated N-cycling at elevated soil temperature and to biochar-induced changes in soil properties and environmental conditions. Methane uptake was not affected by soil warming or biochar. The incorporation of biochar-C into soil was estimated to offset warming-induced elevated GHG emissions for 25 years. Our results highlight the suitability of biochar for C sequestration in cultivated temperate agricultural soil under a future elevated temperature. However, the increased N 2 O emissions under warming limit the GHG mitigation potential of biochar. © 2017 John Wiley & Sons Ltd.

  14. A Brief History of the use of Electromagnetic Induction Techniques in Soil Survey

    Brevik, Eric C.; Doolittle, James

    2017-04-01

    Electromagnetic induction (EMI) has been used to characterize the spatial variability of soil properties since the late 1970s. Initially used to assess soil salinity, the use of EMI in soil studies has expanded to include: mapping soil types; characterizing soil water content and flow patterns; assessing variations in soil texture, compaction, organic matter content, and pH; and determining the depth to subsurface horizons, stratigraphic layers or bedrock, among other uses. In all cases the soil property being investigated must influence soil apparent electrical conductivity (ECa) either directly or indirectly for EMI techniques to be effective. An increasing number and diversity of EMI sensors have been developed in response to users' needs and the availability of allied technologies, which have greatly improved the functionality of these tools and increased the amount and types of data that can be gathered with a single pass. EMI investigations provide several benefits for soil studies. The large amount of georeferenced data that can be rapidly and inexpensively collected with EMI provides more complete characterization of the spatial variations in soil properties than traditional sampling techniques. In addition, compared to traditional soil survey methods, EMI can more effectively characterize diffuse soil boundaries and identify included areas of dissimilar soils within mapped soil units, giving soil scientists greater confidence when collecting spatial soil information. EMI techniques do have limitations; results are site-specific and can vary depending on the complex interactions among multiple and variable soil properties. Despite this, EMI techniques are increasingly being used to investigate the spatial variability of soil properties at field and landscape scales. The future should witness a greater use of multiple-frequency and multiple-coil EMI sensors and integration with other sensors to assess the spatial variability of soil properties. Data analysis

  15. Application of biodegradation screening protocol to contaminated soils from manufactured gas plant sites

    Smith, J.R.; Nakles, D.V.; Cushey, M.A.; Morgan, D.J.; Linz, D.G.

    1990-01-01

    Bioremediation (i.e., land treatment) has been demonstrated to be a viable option for treating a variety of soils contamianted with organics. Conventional treatability studies utilize soil microcosm experiments to evaluate the potential for bioremediation of specific contaminated soils. Unfortunately, soil microcosms take from 4- to 6-months to complete and do not fully exploit the current understanding of the bioremediation process. This paper describes a treatability protocol that investigates underlying mechanisms and can be completed in 2- to 3-months. It is believed that soil bioremediation is governed by the sequential processes of contanate desorption from the soil into the aqueous phase and subsequent oxidation by microorganisms. The relative importance of each process depends upon the contaminant and soil. Accordingly, the treatability protocol has three steps. In the first step, tests are performed to determine soil characteristics. In the second step, tests are performed to characterize the desorption of contaminants from the soil. In the third step, the potential for biological oxidaiton is evaluated with a soil-water slurry reactor that maximizes desorption and provides an optimum environment for microbial growth. This paper provides a thorough discussion of the laboratory protocol including the primary theoretical tenets which serve as its basis. Preliminary procedures and results are presented for soils contaminated with manufactured gas plant (MGP) wastes. Particular attention is focused on biodegradation of polynuclear aromatic hydrocarbons (PAHs)

  16. The Radon Gas in Underground Buildings in Clay Soils. The Plaza Balmis Shelter as a Paradigm.

    Rizo Maestre, Carlos; Echarri Iribarren, Víctor

    2018-05-17

    In healthy buildings, it is considered essential to quantify air quality. One of the most fashionable indicators is radon gas. To determine the presence of this element, which is harmful to health, in the environment, the composition of the soil is studied. The presence of radon gas within a building depends both on the terrain in which it is located and on the composition of the materials of which it is composed, and not as was previously believed, only by the composition of the soil (whether granitic or not). Many countries are currently studying this phenomenon, including Spain where the building regulations regarding the accumulation of radon gas, do not list in their technical codes, the maximum dose that can a building can hold so that it is not harmful to people and the measures to correct excessive accumulation. Therefore, once the possible existence of radon in any underground building has been verified, regardless of the characteristics of the soil, the importance of defining and unifying the regulations on different levels of radon in all architectural constructions is evident. Medical and health science agencies, including the World Health Organization, consider that radon gas is a very harmful element for people. This element, in its gaseous state, is radioactive and it is present in almost soils in which buildings are implanted. Granitic type soils present higher levels of radon gas. Non-granitic soils have traditionally been considered to have very low radon levels. However, this paper demonstrates the relevant presence of radon in non-granitic soils, specifically in clayey soils, by providing the results of research carried out in the underground air raid shelter at Balmis Square in Alicante (Spain). The results of the measurements of radon accumulation in the Plaza Balmis shelter are five times higher than those obtained in a similar ungrounded building. This research addresses the constructive typology of an under-ground building and the radon

  17. [Geochemical characteristics of radon and mercury in soil gas in Lhasa, Tibet, China].

    Zhou, Xiao-Cheng; Du, Jian-Guo; Wang, Chuan-Yuan; Cao, Zhong-Quan; Yi, Li; Liu, Lei

    2007-03-01

    The geochemical characteristics of radon and mercury in soil gas in Lhasa and vicinity are investigated based on the measurements of Rn and Hg concentrations, and environmental quality for Rn and Hg in soil gas was evaluated by means of the index of geoaccumulation. The data of Rn and Hg of 1 579 sampling site indicate that the values of environmental-geochemical background of Rn and Hg are 7 634.9 Bq/m3, 41.5 ng/m3 with standard deviations of 2.7 Bq/m3, 2.2 ng/m3, respectively. The environmental quality for Rn in soil gas is better in the west and east parts of studied area, but becomes moderate pollution (level III) in the north part of the central area. Rn is derived from radioactive elements in granitic sediments in the intermountain basin and granite base, which are the major sources of pollution. The environmental quality for Hg in soil gas becomes gradually polluted from the suburban to the center of urban, and the highest pollution reaches level IV. The background of Hg in soil gas is mainly controlled by compositions of sediments, but the Hg pollution caused by human waste and religionary use of mercury.

  18. Annual survey on the natural gas market: results for 2013

    Cadin, Didier; Moreau, Sylvain

    2015-02-01

    Illustrated by graphs and tables, this publication presents and discusses data regarding the French natural gas market in 2013: origin of the consumed gas and share of the national production, evolution of the inlet-outlet ratio for gas-pipe and gas harbour terminals in France, adjustment of resources to demand in terms of jobs, production, imports and storage, evolution of stored quantities, evolution of consumption, evolution of consumption per sector since 2007, regional supplies in 2012 and 2013

  19. Influence of Flue Gas Desulfurization Gypsum Amendments on Heavy Metal Distribution in Reclaimed Sodic Soils

    Chen, Qun; Wang, Shujuan; Li, Yan; Zhang, Ning; Zhao, Bo; Zhuo, Yuqun; Chen, Changhe

    2015-01-01

    Abstract Although flue gas desulfurization (FGD) gypsum has become an effective soil amendment for sodic soil reclamation, it carries extra heavy metal contamination into the soil environment. The fate of heavy metals introduced by FGD gypsum in sodic or saline–alkali soils is still unclear. This work aims to investigate the effects of FGD gypsum addition on the heavy metal distributions in a sodic soil. Original soil samples were collected from typical sodic land in north China. Soil column leaching tests were conducted to investigate the influence of FGD gypsum addition on the soil properties, especially on distribution profiles of the heavy metals (Pb, Cd, Cr, As, and Hg) in the soil layers. Results showed that pH, electrical conductivity, and exchangeable sodium percentage in amended soils were significantly reduced from 10.2 to 8.46, 1.8 to 0.2 dS/m, and 18.14% to 1.28%, respectively. As and Hg concentrations in the soils were found to be positively correlated with FGD gypsum added. The amount of Hg in the leachate was positively correlated with FGD gypsum application ratio, whereas a negative correlation was observed between the Pb concentration in the leachate and the FGD gypsum ratio. Results revealed that heavy metal concentrations in soils complied well with Environmental Quality Standard for Soils in China (GB15618-1995). This work helps to understand the fate of FGD gypsum-introduced heavy metals in sodic soils and provides a baseline for further environmental risk assessment associated with applying FGD gypsum for sodic soil remediation. PMID:26064038

  20. Influence of Flue Gas Desulfurization Gypsum Amendments on Heavy Metal Distribution in Reclaimed Sodic Soils.

    Chen, Qun; Wang, Shujuan; Li, Yan; Zhang, Ning; Zhao, Bo; Zhuo, Yuqun; Chen, Changhe

    2015-06-01

    Although flue gas desulfurization (FGD) gypsum has become an effective soil amendment for sodic soil reclamation, it carries extra heavy metal contamination into the soil environment. The fate of heavy metals introduced by FGD gypsum in sodic or saline-alkali soils is still unclear. This work aims to investigate the effects of FGD gypsum addition on the heavy metal distributions in a sodic soil. Original soil samples were collected from typical sodic land in north China. Soil column leaching tests were conducted to investigate the influence of FGD gypsum addition on the soil properties, especially on distribution profiles of the heavy metals (Pb, Cd, Cr, As, and Hg) in the soil layers. Results showed that pH, electrical conductivity, and exchangeable sodium percentage in amended soils were significantly reduced from 10.2 to 8.46, 1.8 to 0.2 dS/m, and 18.14% to 1.28%, respectively. As and Hg concentrations in the soils were found to be positively correlated with FGD gypsum added. The amount of Hg in the leachate was positively correlated with FGD gypsum application ratio, whereas a negative correlation was observed between the Pb concentration in the leachate and the FGD gypsum ratio. Results revealed that heavy metal concentrations in soils complied well with Environmental Quality Standard for Soils in China (GB15618-1995). This work helps to understand the fate of FGD gypsum-introduced heavy metals in sodic soils and provides a baseline for further environmental risk assessment associated with applying FGD gypsum for sodic soil remediation.

  1. Amelioration of alkali soil using flue gas desulfurization byproducts: productivity and environmental quality

    Wang, S.J.; Chen, C.H.; Xu, X.C.; Li, Y.J. [Tsing Hua University, Beijing (China). Ministry of Education

    2008-01-15

    In this study, flue gas desulfurization (FGD) byproducts are used to ameliorate alkali soil. The average application rates for soils with low exchangeable sodium percentage (ESP), mid ESP, and high ESP are 20.9, 30.6, and 59.3 Mg ha{sup -1} respectively. The experimental results obtained for 3 consecutive years reveal that the emergence ratios and yields of the crops were 1.1-7.6 times and 1.1-13.9 times those of the untreated control, respectively. The concentrations of Cr, Pb, Cd, As, and Hg in the treated soils are far below the background values stipulated by the Environmental Quality Standard for Soils (GB 15618-1995). Their concentrations in the seeds of corn and alfalfa grown in the treated soils are far below the tolerance limits regulated by National Food Standards of China. The results of this research demonstrate that the amelioration of alkali soils using FGD byproducts is promising.

  2. Poly-use multi-level sampling system for soil-gas transport analysis in the vadose zone.

    Nauer, Philipp A; Chiri, Eleonora; Schroth, Martin H

    2013-10-01

    Soil-gas turnover is important in the global cycling of greenhouse gases. The analysis of soil-gas profiles provides quantitative information on below-ground turnover and fluxes. We developed a poly-use multi-level sampling system (PMLS) for soil-gas sampling, water-content and temperature measurement with high depth resolution and minimal soil disturbance. It is based on perforated access tubes (ATs) permanently installed in the soil. A multi-level sampler allows extraction of soil-gas samples from 20 locations within 1 m depth, while a capacitance probe is used to measure volumetric water contents. During idle times, the ATs are sealed and can be equipped with temperature sensors. Proof-of-concept experiments in a field lysimeter showed good agreement of soil-gas samples and water-content measurements compared with conventional techniques, while a successfully performed gas-tracer test demonstrated the feasibility of the PMLS to determine soil-gas diffusion coefficients in situ. A field application of the PMLS to quantify oxidation of atmospheric CH4 in a field lysimeter and in the forefield of a receding glacier yielded activity coefficients and soil-atmosphere fluxes well in agreement with previous studies. With numerous options for customization, the presented tool extends the methodological choices to investigate soil-gas transport in the vadose zone.

  3. Forecasting the 2011 El Hierro submarine eruption (Canary Islands) on the basis of soil He degassing surveys

    Padrón, E.; Pérez, N. M.; Hernández, P. A.; Melián, G. V.; Padilla, G. D.; Barrancos, J.; Dionis, S.; Rodríguez, F.; Nolasco, D.; Calvo, D.; Hernández, I.; Peraza, M. D.

    2012-04-01

    El Hierro Island is the southwesternmost and the youngest island of the Canary archipelago. Since 16 July, an anomalous seismicity at El Hierro island was recorded by IGN seismic network. After the occurrence of more than 10,000 seismic events, volcanic tremor was recorded since 05:15 of the October 10, by all of the seismic stations on the island, with highest amplitudes recorded in the southernmost station. During the afternoon of 12 October a large light-green coloured area was observed in the sea to the souht of La Restinga village (at the southernmost part of El Hierro island), suggesting the existence of a submarine eruption. Since October 12, frequent episodes of, turbulent gas emission and foaming, and the appearance of steamy lava fragments has been observed on the sea surface. As part of the volcanic surveillance of the island, the Instituto Volcanologico de Canarias (INVOLCAN) geochemical monitoring program is carrying out diffuse helium surveys on the surface environment of El Hierro (soil atmosphere). This nobel gas has been investigated because it has been considered an almost ideal geochemical indicator because it is chemically inert, physically stable, nonbiogenic, sparingly soluble in water under ambient conditions and almost non-adsorbable. At each survey, 600 sampling sites covering the whole island and following an homogeneous distribution are selected for helium measurements in the soil gases, The helium concentration gradients with respect to its value on air (5.24 ppm) allow us to estimate a pure diffusive emission rate of helium throughout the island. The first survey was carried out on the summer of 2003, when the island was on a quiescence period. At this survey, the amount of helium released by the volcanic system of El Hierro was estimated in 6 kg/d. Since the beginning of the seismic unrest, 13 helium emission surveys have been carried out. The helium emission rate has shown an excellent agreement with the evolution of the volcanic

  4. Digital Mapping of Soil Drainage Classes Using Multitemporal RADARSAT-1 and ASTER Images and Soil Survey Data

    Mohamed Abou Niang

    2012-01-01

    Full Text Available Discriminant analysis classification (DAC and decision tree classifiers (DTC were used for digital mapping of soil drainage in the Bras-d’Henri watershed (QC, Canada using earth observation data (RADARSAT-1 and ASTER and soil survey dataset. Firstly, a forward stepwise selection was applied to each land use type identified by ASTER image in order to derive an optimal subset of soil drainage class predictors. The classification models were then applied to these subsets for each land use and merged to obtain a digital soil drainage map for the whole watershed. The DTC method provided better classification accuracies (29 to 92% than the DAC method (33 to 79% according to the land use type. A similarity measure (S was used to compare the best digital soil drainage map (DTC to the conventional soil drainage map. Medium to high similarities (0.6≤S<0.9 were observed for 83% (187 km2 of the study area while 3% of the study area showed very good agreement (S≥0.9. Few soil polygons showed very weak similarities (S<0.3. This study demonstrates the efficiency of combining radar and optical remote sensing data with a representative soil dataset for producing digital maps of soil drainage.

  5. Joint interpretation of geoelectrical and soil-gas measurements for monitoring CO2 releases at a natural analogue

    Sauer, U.; Watanabe, N.; Singh, Ashok

    2014-01-01

    the complex behaviour of temporal variations for the flow patterns. In particular, coupled migration of gas and water plays an important influencing role in this process. Site-specific, near surface geological features and meteorological conditions seem to exert great influence on the degassing pattern...... and flux measurements, self-potential (SP) and geoelectrical surveys) showed that the combination of geophysical methods with soil-gas analysis for mesoscale monitoring of the shallow subsurface above geologic CO2 storages can be a valuable tool for mapping and monitoring potential CO2 spread...... in the subsurface. Three measurement campaigns were undertaken - May 2011, July 2011 and April 2012 - at an analogue site in the Cheb Basin, Czech Republic, with the aim of studying CO2 leakages and their temporal and spatial behaviour. Results of geoelectrical investigations give an insight into the structural...

  6. Testing CO2 Sequestration in an Alkaline Soil Treated with Flue Gas Desulfurization Gypsum (FGDG)

    Han, Y.; Tokunaga, T. K.

    2012-12-01

    Identifying effective and economical methods for increasing carbon storage in soils is of interest for reducing soil CO2 fluxes to the atmosphere in order to partially offset anthropogenic CO2 contributions to climate change This study investigates an alternative strategy for increasing carbon retention in soils by accelerating calcite (CaCO3) precipitation and promoting soil organic carbon (SOC) complexation on mineral surfaces. The addition of calcium ion to soils with pH > 8, often found in arid and semi-arid regions, may accelerate the slow process of calcite precipitation. Increased ionic strength from addition of a soluble Ca source also suppresses microbial activity which oxidizes SOC to gaseous CO2. Through obtaining C mass balances in soil profiles, this study is quantifying the efficiency of gypsum amendments for mitigating C losses to the atmosphere. The objective of this study is to identify conditions in which inorganic and organic C sequestration is practical in semi-arid and arid soils by gypsum treatment. As an inexpensive calcium source, we proposed to use flue gas desulfurization gypsum (FGDG), a byproduct of fossil fuel burning electric power plants. To test the hypothesis, laboratory column experiments have been conducted in calcite-buffered soil with addition of gypsum and FGDG. The results of several months of column monitoring are demonstrating that gypsum-treated soil have lowered amounts of soil organic carbon loss and increased inorganic carbon (calcite) production. The excess generation of FGDG relative to industrial and agricultural needs, FGDG, is currently regarded as waste. Thus application of FGDG application in some soils may be an effective and economical means for fixing CO2 in soil organic and inorganic carbon forms.Soil carbon cycle, with proposed increased C retention by calcite precipitation and by SOC binding onto soil mineral surfaces, with both processes driven by calcium released from gypsum dissolution.

  7. Grazing reduces soil greenhouse gas fluxes in global grasslands: a meta-analysis

    Tang, Shiming; Tian, Dashuan; Niu, Shuli

    2017-04-01

    Grazing causes a worldwide degradation in grassland and likely alters soil greenhouse gas fluxes (GHGs). However, the general patterns of grazing-induced changes in grassland soil GHGs and the underlying mechanisms remain unclear. Thus, we synthesized 63 independent experiments in global grasslands that examined grazing impacts on soil GHGs (CO2, CH4 and N2O). We found that grazing with light or moderate intensity did not significantly influence soil GHGs, but consistently depressed them under heavy grazing, reducing CO2 emission by 10.55%, CH4 uptake by 19.24% and N2O emission by 28.04%. The reduction in soil CO2 was mainly due to decreased activity in roots and microbes (soil respiration per unit root and microbial biomass), which was suppressed by less water availability due to higher soil temperature induced by lower community cover under heavy grazing. N2O emission decreased with grazing-caused decline in soil total N. The inhibitory effect on methanotroph activities by water stress is responsible for the decreased CH4 uptake. Furthermore, grazing duration and precipitation also influenced the direction and magnitude of responses in GHGs fluxes. Overall, our results indicate that the reduction in soil CO2 and N2O emission under heavy grazing is partially compensated by the decrease in CH4 uptake, which is mainly regulated by variations in soil moisture.

  8. Application of soil radon survey to searching for sandstone-type uranium deposit at western margin of Ordos basin

    Liu Hanbin; Yin Jinshuang; Cui Yonghui

    2006-01-01

    On the basis of condition tests of soil radon survey at certain uranium deposit in Ordos basin, regional soil radon survey was carried but in a study area of western margin of Ordos basin. By processing of soil radon survey data, five anomalous areas with certain metallogenic potential have been delineated. Then, discovered anomalies have been interpreted and evaluated for providing important reference for further drilling work. Research results indicate that by soil radon survey, anomalies may be distinguished in a basin, and soil radon survey could be an important geochemical prospecting method for rapid evaluation of sandstone-type uranium deposit in basin areas. (authors)

  9. Measurement of radon exhalation rate and soil gas radon concentration in areas of southern Punjab (Pakistan)

    Mujahid, S. A.; Hussain, S.; Ramzan, M.

    2010-01-01

    Plastic track detectors were used to measure the radon concentration and exhalation rate from the soil samples. The samples were collected from areas of southern Punjab (Pakistan). In a laboratory experiment, passive alpha dosemeters were installed inside cylindrical bottles containing the soil samples. The radon concentrations and the radon exhalation rate were found in the ranges of 34±7 to 260±42 Bq m -3 and 38±8 to 288±46 mBq m -2 h -1 , respectively. The on-site measurements of radon in the soil gas were also carried out in these areas using a scintillation alpha counter. The concentration of radon in the soil gas was found in the range of 423±82-3565±438 Bq m -3 . (authors)

  10. Long-term soil gas flux and root mortality, Tapajos National Forest

    W. L. Silver; A. W. Thompson; M. E. McGroddy; R. K. Varner; J. R. Robertson; J. D. Dias; H. Silva; P. Crill; M. Keller

    2012-01-01

    This data set reports measurements of trace gas fluxes of methane (CH4), nitric oxide (N2O), nitrous oxide (NO), carbon dioxide (CO2) from soils at a study site in the Tapajos National Forest (TNF), near the km 83 on the Santarem-Cuiaba Highway south of Santarem, Para, Brazil. Data for root mass and carbon content, soil nitrogen (N), nitrification, and moisture content...

  11. Geographical information system for radon gas from soil measurement

    Orlando, P.; Amici, M.; Altieri, A.; Massari, P.; Miccadei, E.; Onofri, A.; Orlando, C.; Paolelli, C.; Paron, P.; Perticaroli, P.; Piacentini, T.; Silvestri, C.; Minach, L.; Verdi, L.; Bertolo, A.; Trotti, F.

    2000-03-01

    The working program foresees the realization of an geographical information system for the check in field of the geological parameters and determination of uranium and radium contents in various type of rocks. It is here also pointed out a measuring method for radon concentration in soil [it

  12. Mapping of 222Rn and 4He in soil gas over a karstic limestone-granite boundary: correlation of high indoor 222Rn with zones of enhanced permeability

    O'Connor, P.J.; Gallagher, V.; Van den Boom, G.

    1992-01-01

    Recent indoor radon reconnaissance surveys in Ireland have identified buildings with high radon concentrations (up to 1700 Bq.m -3 ) overlying Carboniferous karstic limestone sequences in the western part of the country. A detailed investigation of indoor 222 Rn and soil gas 222 Rn and 4 He concentrations has been carried out over a karstic limestone-uraniferous granite boundary in County Galway. High indoor 222 Rn concentrations occur in dwellings over both lithologies. Radon migratory routes in bedrock and overburden appear to be controlled by zones of enhanced permeability, e.g. fractures, faults, etc. which are defined by linear arrays of elevated 4 He soil gas values. While the ultimate source of radon remains conjectural, the greatly enhanced permeability of karstified limestone is thought to be of fundamental importance in providing a means of rapid radon transport into overlying soils and buildings. (author)

  13. Soil Gas Sample Handling: Evaluation of Water Removal and Sample Ganging

    Fritz, Brad G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Abrecht, David G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hayes, James C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mendoza, Donaldo P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-10-31

    Soil gas sampling is currently conducted in support of Nuclear Test Ban treaty verification. Soil gas samples are collected and analyzed for isotopes of interest. Some issues that can impact sampling and analysis of these samples are excess moisture and sample processing time. Here we discuss three potential improvements to the current sampling protocol; a desiccant for water removal, use of molecular sieve to remove CO2 from the sample during collection, and a ganging manifold to allow composite analysis of multiple samples.

  14. Radon in soil gas in the metropolitan region of Belo Horizonte, Brazil

    Teixeira, Giane Gariglio; Rocha, Zildete

    2007-01-01

    Radon, the natural radioactive gas is produced by the radioactive decay of uranium and thorium which are ubiquitous, specially in rock and soil. By diffusion and convection. Radon migrate from the rocks and to the groundwater and to the soil and from them the radon migrate through fissures, pipes and hales to the surface. Measurements were carried out in the Metropolitan Region of Belo Horizonte, whose greatest part of the in habitants occupies the great pre cambrian unit of the Iron Quadrangle of Minas Gerais denominated 'Granitic Gneissic Complex', composed of Archean rocks of age between 3,2 Ga and 2,6 Ga. The part in which occurs in the municipal area of Belo Horizonte was denominated as Complexo Belo Horizonte, whose most characteristics rocks named Gneiss Belo Horizonte. The soil gas radon concentrations were determined by using a samples and a continuos flow through ionization chamber detector AlphaGUARD PQ2000PRO - Genitron Instruments GmbH in a Instrumental Neutron Activation Analysis). Most results of radon concentration soil gas were in the range 10 kBq/m 3 to 50 kBq/m 3 . This values, according to the established Swedish Criteria are normal risk values. For soils classified as normal risk require 'radon protective construction', but the necessity of mitigation actions will depend on other factors, for example the soil permeability and rock type. (author)

  15. Statistical sampling strategies for survey of soil contamination

    Brus, D.J.

    2011-01-01

    This chapter reviews methods for selecting sampling locations in contaminated soils for three situations. In the first situation a global estimate of the soil contamination in an area is required. The result of the surey is a number or a series of numbers per contaminant, e.g. the estimated mean

  16. The diversity of methoxyphenols released by pyrolysis-gas chromatography as predictor of soil carbon storage.

    Jiménez-González, Marco A; Álvarez, Ana M; Carral, Pilar; González-Vila, Francisco J; Almendros, Gonzalo

    2017-07-28

    The variable extent to which environmental factors are involved in soil carbon storage is currently a subject of controversy. In fact, justifying why some soils accumulate more organic matter than others is not trivial. Some abiotic factors such as organo-mineral associations have classically been invoked as the main drivers for soil C stabilization. However, in this research indirect evidences based on correlations between soil C storage and compositional descriptors of the soil organic matter are presented. It is assumed that the intrinsic structure of soil organic matter should have a bearing in the soil carbon storage. This is examined here by focusing on the methoxyphenols released by direct pyrolysis from a wide variety of topsoil samples from continental Mediterranean ecosystems from Spain with different properties and carbon content. Methoxyphenols are typical signature compounds presumptively informing on the occurrence and degree of alteration of lignin in soils. The methoxyphenol assemblages (12 major guaiacyl- and syringyl-type compounds) were analyzed by pyrolysis-gas chromatography-mass spectrometry. The Shannon-Wiener diversity index was chosen to describe the complexity of this phenolic signature. A series of exploratory statistical analyses (simple regression, partial least squares regression, multidimensional scaling) were applied to analyze the relationships existing between chemical and spectroscopic characteristics and the carbon content in the soils. These treatments coincided in pointing out that significant correlations exist between the progressive molecular diversity of the methoxyphenol assemblages and the concentration of organic carbon stored in the corresponding soils. This potential of the diversity in the phenolic signature as a surrogate index of the carbon storage in soils is tentatively interpreted as the accumulation of plant macromolecules altered into microbially reworked structures not readily recognized by soil enzymes. From

  17. Transport and reaction processes affecting the attenuation of landfill gas in cover soils

    Molins, S.; Mayer, K.U.; Scheutz, Charlotte

    2008-01-01

    of methane, chlorofluorocarbons, and hydrochlorofluorocarbons to the atmosphere. This study was conducted to investigate the effect of oxidation reactions on the overall gas transport regime and to evaluate, the contributions of various gas transport processes on methane attenuation in landfill cover soils....... For this purpose, a reactive transport model that includes advection and the Dusty Gas Model for simulation of multicomponent gas diffusion was used. The simulations are constrained by data from a series of counter-gradient laboratory experiments. Diffusion typically accounts for over 99% of methane emission...... to the atmosphere. Oxygen supply into the soil column is driven exclusively by diffusion, whereas advection outward offsets part of the diffusive contribution. In the reaction zone, methane consumption reduces the pressure gradient, further decreasing the significance of advection near the top of the column...

  18. Soil-gas monitoring: A tool for fault delineation studies along Hsinhua Fault (Tainan), Southern Taiwan

    Walia, Vivek; Lin, Shih Jung; Fu, Ching Chou; Yang, Tsanyao Frank; Hong, Wei-Li; Wen, Kuo-Liang; Chen, Cheng-Hong

    2010-01-01

    Many studies have shown the soil gas method to be one of the most reliable investigation tools in the research of earthquake precursory signals and fault delineation. The present research is aimed finding the relationship between soil gas distribution and tectonic systems in the vicinity of the Hsinhua Fault zone in the Tainan area of Southern Taiwan. More than 110 samples were collected along 13 traverses to find the spatial distribution of Rn, He, CO 2 and N 2 . The spatial congruence of all the gases shows that N 2 is the most probable carrier gas of He, whereas CO 2 seems to be a good carrier gas of Rn in this area. From the spatial distribution of Rn, He, CO 2 and N 2 the trace of Hsinhua Fault and neotectonic features can be identified. The spatial distribution of studied gases shows a clear anomalous trend ENE-SWS along the Hsinhua Fault.

  19. Experiences with a new soil gas technique for detecting petroleum pollution

    Mazac, O.; Landa, I.; Rohde, J.R.; Kelly, W.E.

    1996-01-01

    This paper presents field experiences obtained with a new technology for detecting petroleum pollution in soil and ground water based on in situ determination of hydrocarbon concentrations in soil air. Ecoprobe is a new soil gas device from RS-Dynamics in the Czech Republic. The rugged waterproof device is equipped with a built-in computer-controlled semiconductor sensor. Three case histories are presented that demonstrate the use of the equipment under typical conditions. Two case histories present the use of the device under typical field conditions; the third case history compares results from the Ecoprobe and a commercial photoionization detector (PID) device

  20. Greenhouse gas emissions from a chinampa soil or floating gardens in Mexico

    Ortiz-Cornejo, Nadia Livia; Luna-Guido, Marco; Rivera-Espinoza, Yadira; Vásquez-Murrieta, María Soledad; Ruíz-Valdiviezo, Víctor Manuel; Dendooven, Luc

    2015-01-01

    Agriculture in chinampas or 'floating gardens', is still found on the south of Mexico City, it is a high yield pre-Columbian cultivation system, which has soils enriched with organic matter. The objective of this research was to determine the greenhouse gas (GHG) emissions from a chinampa soil cultivated with amaranth (Amaranthus hypochondriacus L.), maize (Zea mays L.) or uncultivated. The soil was characterized and fluxes of GHG (CO2, N2O and CH4) were monitored for one year. The chinampa s...

  1. A blue carbon soil database: Tidal wetland stocks for the US National Greenhouse Gas Inventory

    Feagin, R. A.; Eriksson, M.; Hinson, A.; Najjar, R. G.; Kroeger, K. D.; Herrmann, M.; Holmquist, J. R.; Windham-Myers, L.; MacDonald, G. M.; Brown, L. N.; Bianchi, T. S.

    2015-12-01

    Coastal wetlands contain large reservoirs of carbon, and in 2015 the US National Greenhouse Gas Inventory began the work of placing blue carbon within the national regulatory context. The potential value of a wetland carbon stock, in relation to its location, soon could be influential in determining governmental policy and management activities, or in stimulating market-based CO2 sequestration projects. To meet the national need for high-resolution maps, a blue carbon stock database was developed linking National Wetlands Inventory datasets with the USDA Soil Survey Geographic Database. Users of the database can identify the economic potential for carbon conservation or restoration projects within specific estuarine basins, states, wetland types, physical parameters, and land management activities. The database is geared towards both national-level assessments and local-level inquiries. Spatial analysis of the stocks show high variance within individual estuarine basins, largely dependent on geomorphic position on the landscape, though there are continental scale trends to the carbon distribution as well. Future plans including linking this database with a sedimentary accretion database to predict carbon flux in US tidal wetlands.

  2. Challenges of conservation agriculture practices on silty soils. Effects on soil pore and gas transport characteristics in North-eastern Italy

    Piccoli, Ilaria; Schjønning, Per; Lamandé, Mathieu

    2017-01-01

    highlighted low transmission properties of the silty soils independently from agronomic management. Both air permeability and relative gas diffusivity showed poor aerated conditions being generallytreatments affected the transmission properties only in the coarsest soil...... of this study was to evaluate the effect of CA practices on gas transport characteristics in the silty soils of the Veneto Region (North-Eastern Italy). In 2010, a field experiment comparing CA practices (no-tillage, cover crop and residues retention) to conventional intensive tillage (IT) system...... was established in four farms located in the Veneto low plain. In fall 2015, 144 undisturbed 100 cm3 soil cores where collected at two different layers (3–6.5 cm and 20–23.5 cm) and analysed for air-filled porosity, air permeability, gas diffusivity and soil structure indices derived. Gas transport measurements...

  3. Structure-Dependent Water-Induced Linear Reduction Model for Predicting Gas Diffusivity and Tortuosity in Repacked and Intact Soil

    Møldrup, Per; Chamindu, T. K. K. Deepagoda; Hamamoto, S.

    2013-01-01

    The soil-gas diffusion is a primary driver of transport, reactions, emissions, and uptake of vadose zone gases, including oxygen, greenhouse gases, fumigants, and spilled volatile organics. The soil-gas diffusion coefficient, Dp, depends not only on soil moisture content, texture, and compaction...... but also on the local-scale variability of these. Different predictive models have been developed to estimate Dp in intact and repacked soil, but clear guidelines for model choice at a given soil state are lacking. In this study, the water-induced linear reduction (WLR) model for repacked soil is made...... air) in repacked soils containing between 0 and 54% clay. With Cm = 2.1, the SWLR model on average gave excellent predictions for 290 intact soils, performing well across soil depths, textures, and compactions (dry bulk densities). The SWLR model generally outperformed similar, simple Dp/Do models...

  4. Biochar-mediated reductions in greenhouse gas emissions from soil amended with anaerobic digestates

    Martin, Sarah L.; Clarke, Michèle L.; Othman, Mukhrizah; Ramsden, Stephen J.; West, Helen M.

    2015-01-01

    This investigation examines nitrous oxide (N 2 O) fluxes from soil with simultaneous amendments of anaerobic digestates and biochar. The main source of anthropogenic emissions of N 2 O is agriculture and in particular, manure and slurry application to fields. Anaerobic digestates are increasingly used as a fertiliser and interest is growing in their potential as sources of N 2 O via nitrification and denitrification. Biochar is a stable product of pyrolysis and may affect soil properties such as cation exchange capacity and water holding capacity. Whilst work has been conducted on the effects of biochar amendment on N 2 O emissions in soils fertilised with mineral fertilisers and raw animal manures, little work to date has focused on the effects of biochar on nitrogen transformations within soil amended with anaerobic digestates. The aim of the current investigation was to quantify the effects of biochar application on ammonification, nitrification and N 2 O fluxes within soil amended with three anaerobic digestates derived from different feedstocks. A factorial experiment was undertaken in which a sandy loam soil (Dunnington Heath series) was either left untreated, or amended with three different anaerobic digestates and one of three biochar treatments; 0%, 1% or 3%. Nitrous oxide emissions were greatest from soil amended with anaerobic digestate originating from a maize feedstock. Biochar amendment reduced N 2 O emissions from all treatments, with the greatest effect observed in treatments with maximum emissions. The degree of N 2 O production and efficacy of biochar amelioration of gas emissions is discussed in context of soil microbial biomass and soil available carbon. - Highlights: • Nitrous oxide was emitted from anaerobic digestates applied to soil. • Simultaneous amendment of soil with biochar and anaerobic digestate reduced N 2 O emissions. • Soil nitrate accumulation occurred but was digestate dependent

  5. Soil

    Freudenschuss, A.; Huber, S.; Riss, A.; Schwarz, S.; Tulipan, M.

    2002-01-01

    Environmental soil surveys in each province of Austria have been performed, soils of about 5,000 sites were described and analyzed for nutrients and pollutants, the majority of these data are recorded in the soil information system of Austria (BORIS) soil database, http://www.ubavie.gv.at/umweltsituation/boden/boris), which also contains a soil map of Austria, data from 30 specific investigations mainly in areas with industry and results from the Austria - wide cesium investigation. With respect to the environmental state of soils a short discussion is given, including two geographical charts, one showing which sites have soil data (2001) and the other the cadmium distribution in top soils according land use (forest, grassland, arable land, others). Information related to the soil erosion, Corine land cover (Europe-wide land cover database), evaluation of pollutants in soils (reference values of As, Cd, Co, Cr, Cu, Hg, Mo, Ni, Se, Pb, Tl, Va, Zn, AOX, PAH, PCB, PCDD/pcdf, dioxin), and relevant Austrian and European standards and regulations is provided. Figs. 2, Tables 4. (nevyjel)

  6. Towards a model-based inventory of soil organic carbon in agricultural soils for the Swiss greenhouse gas reporting

    Staudt, K.; Leifeld, J.; Bretscher, D.; Fuhrer, J.

    2012-04-01

    The Swiss inventory submission under the United Nations Framework Convention on Climate Change (UNFCCC) reports on changes in soil organic carbon stocks under different land-uses and land-use changes. The approach currently employed for cropland and grassland soils combines Tier 1 and Tier 2 methods and is considered overly simplistic. As the UNFCC encourages countries to develop Tier 3 methods for national greenhouse gas reporting, we aim to build up a model-based inventory of soil organic carbon in agricultural soils in Switzerland. We conducted a literature research on currently employed higher-tier methods using process-based models in four countries: Denmark, Sweden, Finland and the USA. The applied models stem from two major groups differing in complexity - those belonging to the group of general ecosystem models that include a plant-growth submodel, e.g. Century, and those that simulate soil organic matter turnover but not plant-growth, e.g. ICBM. For the latter group, carbon inputs to the soil from plant residues and roots have to be determined separately. We will present some aspects of the development of a model-based inventory of soil organic carbon in agricultural soils in Switzerland. Criteria for model evaluation are, among others, modeled land-use classes and land-use changes, spatial and temporal resolution, and coverage of relevant processes. For model parameterization and model evaluation at the field scale, data from several long-term agricultural experiments and monitoring sites in Switzerland is available. A subsequent regional application of a model requires the preparation of regional input data for the whole country - among others spatio-temporal meteorological data, agricultural and soil data. Following the evaluation of possible models and of available data, preference for application in the Swiss inventory will be given to simpler model structures, i.e. models without a plant-growth module. Thus, we compared different allometric relations

  7. Survey of radioactivity levels of soil in Shanghai

    Ren Lihua

    1993-01-01

    The gross α and β activities on soil were measured by a mode FJ-2600 air-flow type alpha and beta counter. 204 sampling points including 173 grid points and 31 special points were set in the whole city. The ranges of the gross α and β activities in soil at the grid points are 816.5-2056.1 Bq/kg and 633.2-896.4 Bq/kg respectively. All these values are within the normal range of background activities. Only few special points are beyond the normal range. The results of statistical test indicate that the gross α and β activities show a normal distribution and that the levels of gross activity correlate with the sampling point, soil type and the geomorphology. It seems that the wide range of background values is related to the differences in natural conditions, such as the terrestrial formation, the soil-forming parent materials, etc., and the human activity

  8. Contaminant Gradients in Trees: Directional Tree Coring Reveals Boundaries of Soil and Soil-Gas Contamination with Potential Applications in Vapor Intrusion Assessment.

    Wilson, Jordan L; Samaranayake, V A; Limmer, Matthew A; Schumacher, John G; Burken, Joel G

    2017-12-19

    Contaminated sites pose ecological and human-health risks through exposure to contaminated soil and groundwater. Whereas we can readily locate, monitor, and track contaminants in groundwater, it is harder to perform these tasks in the vadose zone. In this study, tree-core samples were collected at a Superfund site to determine if the sample-collection location around a particular tree could reveal the subsurface location, or direction, of soil and soil-gas contaminant plumes. Contaminant-centroid vectors were calculated from tree-core data to reveal contaminant distributions in directional tree samples at a higher resolution, and vectors were correlated with soil-gas characterization collected using conventional methods. Results clearly demonstrated that directional tree coring around tree trunks can indicate gradients in soil and soil-gas contaminant plumes, and the strength of the correlations were directly proportionate to the magnitude of tree-core concentration gradients (spearman's coefficient of -0.61 and -0.55 in soil and tree-core gradients, respectively). Linear regression indicates agreement between the concentration-centroid vectors is significantly affected by in planta and soil concentration gradients and when concentration centroids in soil are closer to trees. Given the existing link between soil-gas and vapor intrusion, this study also indicates that directional tree coring might be applicable in vapor intrusion assessment.

  9. A guide for the use of digital elevation model data for making soil surveys

    Klingebiel, A.A.; Horvath, Emil H.; Reybold, William U.; Moore, D.G.; Fosnight, E.A.; Loveland, Thomas R.

    1988-01-01

    The intent of this publication is twofold: (1) to serve as a user guide for soil scientists and others interested in learning about the value and use of digital elevation model (DEM) data in making soil surveys and (2) to provide documentation of the Soil Landscape Analysis Project (SLAP). This publication provides a step-by-step guide on how digital slope-class maps are adjusted to topographic maps and orthophotoquads to obtain accurate slope-class maps, and how these derivative maps can be used as a base for soil survey premaps. In addition, guidance is given on the use of aspect-class maps and other resource data in making pre-maps. The value and use of tabular summaries are discussed. Examples of the use of DEM products by the authors and by selected field soil scientists are also given. Additional information on SLAP procedures may be obtained from USDA, Soil Conservation Service, Soil Survey Division, P.O. Box 2890, Washington, D.C. 20013, and from references (Horvath and others, 1987; Horvath and others, 1983; Klingebiel and others, 1987; and Young, 1987) listed in this publication. The slope and aspect products and the procedures for using these products have evolved during 5 years of cooperative research with the USDA, Soil Conservation Service and Forest Service, and the USDI, Bureau of Land Management.

  10. Portable Automation of Static Chamber Sample Collection for Quantifying Soil Gas Flux

    Davis, Morgan P.; Groh, Tyler A.; Parkin, Timothy B.; Williams, Ryan J.; Isenhart, Thomas M.; Hofmockel, Kirsten S.

    2018-01-01

    Quantification of soil gas flux using the static chamber method is labor intensive. The number of chambers that can be sampled is limited by the spacing between chambers and the availability of trained research technicians. An automated system for collecting gas samples from chambers in the field would eliminate the need for personnel to return to the chamber during a flux measurement period and would allow a single technician to sample multiple chambers simultaneously. This study describes Chamber Automated Sampling Equipment (FluxCASE) to collect and store chamber headspace gas samples at assigned time points for the measurement of soil gas flux. The FluxCASE design and operation is described, and the accuracy and precision of the FluxCASE system is evaluated. In laboratory measurements of nitrous oxide (N2O), carbon dioxide (CO2), and methane (CH4) concentrations of a standardized gas mixture, coefficients of variation associated with automated and manual sample collection were comparable, indicating no loss of precision. In the field, soil gas fluxes measured from FluxCASEs were in agreement with manual sampling for both N2O and CO2. Slopes of regression equations were 1.01 for CO2 and 0.97 for N2O. The 95% confidence limits of the slopes of the regression lines included the value of one, indicating no bias. Additionally, an expense analysis found a cost recovery ranging from 0.6 to 2.2 yr. Implementing the FluxCASE system is an alternative to improve the efficiency of the static chamber method for measuring soil gas flux while maintaining the accuracy and precision of manual sampling.

  11. A literature survey on gas turbines materials - recent advances

    Gras, J.M.

    1992-10-01

    The 9001F gas turbine (rating of about 200 MW) is one of the most recent versions of the 9000 series, benefitting from the developments and technological advances, notably in regard to structural materials. In the framework of the EDF gas turbine engineering and construction program, evaluating the nature of these developments can provide guidance in appraising the construction materials proposed by other manufacturers. After a brief comparison between the Gennevilliers 9001F engine and the 85 MW 9000B gas turbine at Bouchain, ordered by EDF in 1971, various research aspects for optimizing gas turbine refractory material mechanical properties and corrosion resistance (superalloys, monolithic ceramics and composite ceramics) are presented; present current and future trends for high power equipment of this type are also discussed

  12. Fracture mapping in clays: the design and application of a mobile gas geochemistry laboratory for the analysis of soil gases

    Gregory, R.G.

    1988-02-01

    Integrated soil gas analyses for helium, radon, carbon dioxide, oxygen and organic gases allow the accurate interpretation of soil gas signatures as indicators of underlying structure. The most important features observed in the patterns of soil gas behaviour are large variations over faults and fractures. Structures such as these provide channelways for fluid movement in the upper crust. The construction of a mobile gas geochemistry laboratory for the analysis of soil gases at field investigation sites, and the subsequent trials carried out to evaluate the laboratory, clearly show that the soil gas investigation technique is accurate and viable as an independent site investigation method for the study of fracturing and groundwater movement around potential waste repository sites. (author)

  13. Portable automation of static chamber sample collection for quantifying soil gas flux

    The collection of soil gas flux using the static chamber method is labor intensive. The number of chambers that can be sampled in a given time period is limited by the spacing between chambers and the availability of trained research technicians. However, the static chamber method can limit spatial ...

  14. A simple technique for the measurement of 222Rn in soil gas using LLRDS

    Karunakara, N.

    2010-01-01

    The details of the technique of soil gas measurement using LLRDS and results obtained for field measurements at different locations of Mangalore and the results of comparative study with the AlphaGuard along with the possible scope for the improvisation are presented and discussed in this paper

  15. Comparative measurements of soil gas radon concentration using thermoluminescent and track detectors

    Turek, Karel; Gelev, M.; Dimov, I.

    2004-01-01

    Roč. 38, spec. iss. (2004), s. 843-846 ISSN 1350-4487 Institutional research plan: CEZ:AV0Z1048901 Keywords : soil gas * radon concentration * thermoluminescent detectors Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 0.664, year: 2004

  16. Soil-Gas Radon Anomaly Map of an Unknown Fault Zone Area, Chiang Mai, Northern Thailand

    Udphuay, S.; Kaweewong, C.; Imurai, W.; Pondthai, P.

    2015-12-01

    Soil-gas radon concentration anomaly map was constructed to help detect an unknown subsurface fault location in San Sai District, Chiang Mai Province, Northern Thailand where a 5.1-magnitude earthquake took place in December 2006. It was suspected that this earthquake may have been associated with an unrecognized active fault in the area. In this study, soil-gas samples were collected from eighty-four measuring stations covering an area of approximately 50 km2. Radon in soil-gas samples was quantified using Scintrex Radon Detector, RDA-200. The samplings were conducted twice: during December 2014-January 2015 and March 2015-April 2015. The soil-gas radon map obtained from this study reveals linear NNW-SSE trend of high concentration. This anomaly corresponds to the direction of the prospective fault system interpreted from satellite images. The findings from this study support the existence of this unknown fault system. However a more detailed investigation should be conducted in order to confirm its geometry, orientation and lateral extent.

  17. Soil Survey Geographic (SSURGO) database for Cibola National Forest Area, New Mexico, Parts of Catron, Cibola, McKinley, Sandoval, Sierra and Socorro Counties

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  18. Soil Survey Geographic (SSURGO) database for Chinle Area, Parts of Apache and Navajo Counties, Arizona and San Juan County, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  19. Soil Survey Geographic (SSURGO) database for Fort Defiance Area, Parts of Apache and Navajo Counties, Arizona, and McKinley and San Juan Counties, New Mexico

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  20. Soil Survey Geographic (SSURGO) database for White Sands Missile Range, New Mexico, Parts of Dona Ana, Lincoln, Otero, Sierra and Socorro Counties

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  1. Soil Survey Geographic (SSURGO) database for Santa Fe National Forest Area, New Mexico, Parts of Mora, Rio Arriba, Sandoval and San Miguel Counties

    Earth Data Analysis Center, University of New Mexico — This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The...

  2. Application of colloidal gas aphron suspensions produced from Sapindus mukorossi for arsenic removal from contaminated soil.

    Mukhopadhyay, Soumyadeep; Mukherjee, Sumona; Hashim, Mohd Ali; Sen Gupta, Bhaskar

    2015-01-01

    Colloidal gas aphron dispersions (CGAs) can be described as a system of microbubbles suspended homogenously in a liquid matrix. This work examines the performance of CGAs in comparison to surfactant solutions for washing low levels of arsenic from an iron rich soil. Sodium Dodecyl Sulfate (SDS) and saponin, a biodegradable surfactant, obtained from Sapindus mukorossi or soapnut fruit were used for generating CGAs and solutions for soil washing. Column washing experiments were performed in down-flow and up flow modes at a soil pH of 5 and 6 using varying concentration of SDS and soapnut solutions as well as CGAs. Soapnut CGAs removed more than 70% arsenic while SDS CGAs removed up to 55% arsenic from the soil columns in the soil pH range of 5-6. CGAs and solutions showed comparable performances in all the cases. CGAs were more economical since it contains 35% of air by volume, thereby requiring less surfactant. Micellar solubilization and low pH of soapnut facilitated arsenic desorption from soil column. FT-IR analysis of effluent suggested that soapnut solution did not interact chemically with arsenic thereby facilitating the recovery of soapnut solution by precipitating the arsenic. Damage to soil was minimal arsenic confirmed by metal dissolution from soil surface and SEM micrograph. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Soil greenhouse gas emissions and carbon budgeting in a short-hydroperiod floodplain wetland

    Batson, Jackie; Noe, Gregory B.; Hupp, Cliff R.; Krauss, Ken W.; Rybicki, Nancy B.; Schenk, Edward R.

    2015-01-01

    Understanding the controls on floodplain carbon (C) cycling is important for assessing greenhouse gas emissions and the potential for C sequestration in river-floodplain ecosystems. We hypothesized that greater hydrologic connectivity would increase C inputs to floodplains that would not only stimulate soil C gas emissions but also sequester more C in soils. In an urban Piedmont river (151 km2 watershed) with a floodplain that is dry most of the year, we quantified soil CO2, CH4, and N2O net emissions along gradients of floodplain hydrologic connectivity, identified controls on soil aerobic and anaerobic respiration, and developed a floodplain soil C budget. Sites were chosen along a longitudinal river gradient and across lateral floodplain geomorphic units (levee, backswamp, and toe slope). CO2 emissions decreased downstream in backswamps and toe slopes and were high on the levees. CH4 and N2O fluxes were near zero; however, CH4emissions were highest in the backswamp. Annual CO2 emissions correlated negatively with soil water-filled pore space and positively with variables related to drier, coarser soil. Conversely, annual CH4 emissions had the opposite pattern of CO2. Spatial variation in aerobic and anaerobic respiration was thus controlled by oxygen availability but was not related to C inputs from sedimentation or vegetation. The annual mean soil CO2 emission rate was 1091 g C m−2 yr−1, the net sedimentation rate was 111 g C m−2 yr−1, and the vegetation production rate was 240 g C m−2 yr−1, with a soil C balance (loss) of −338 g C m−2 yr−1. This floodplain is losing C likely due to long-term drying from watershed urbanization.

  4. Assessment of soil-gas, seep, and soil contamination at the North Range Road Landfill, Fort Gordon, Georgia, 2008-2009

    Landmeyer, James E.; Falls, W. Fred; Ratliff, W. Hagan; Wellborn, John B.

    2011-01-01

    Soil gas, seeps, and soil were assessed for contaminants at the North Range Road Landfill at Fort Gordon, Georgia, from October 2008 to September 2009. The assessment included delineating organic contaminants present in soil-gas samples beneath the area estimated to be the landfill and in water samples collected from three seeps at the base of the landfill. Inorganic contaminants were determined in three seep samples and in soil samples. This assessment was conducted to provide environmental contamination data to Fort Gordon pursuant to requirements for the Resource Conservation and Recovery Act Part B Hazardous Waste Permit process.

  5. Gas exchange of four woody species under salinity and soil waterlogging

    Alan D. Lima

    Full Text Available ABSTRACT The objective of this study was to evaluate gas exchanges in seedlings of forest species grown in saline soils and subjected to soil waterlogging cycles. The experimental design was completely randomized in a factorial arrangement, with four forest species: Myracrodruon urundeuva Fr Allemão, Mimosa caesalpiniifolia Benth, Tabebuia impetiginosa (Mart. ex. DC. Standl and Azadirachta indica A. Juss, two soil salinity levels (1.2 and 8.6 dS m-1 and two water regimes (with and without waterlogging. Measurements of stomatal conductance, transpiration and CO2 assimilation rate were performed before and after each waterlogging period. The interaction of the highest saline level (8.6 dS m-1 and waterlogging caused greater reductions in leaf gas exchange, except for Mimosa caesalpiniifolia Benth. Tabebuia impetiginosa (Mart. ex. DC. Standl was the species with highest sensitivity to both studied factors of stress.

  6. Analysis of organic pollutants in the soils of the disused gas plants. Experimental evaluation and recommendations

    Caron, S.; Carmant, S.

    1997-01-01

    In France, environmental investigations are at the moment carried out on numerous disused gas plants sites, which soils can have been polluted by the by-products generated during the fabrication of the gas (most of the time coal tar). Within the context of those investigations, diagnosis of the pollution of soils by the analytical way is an essential operation on the basis of which the risks are evaluated and the treatments are decided. Moreover, the evolution of the pollution level during the cleaning up of the soils and the efficiency of the treatment can only be measured by the analytical way. Until today, analytical aspects, relative to the study of polluted soils can be discussed. Indeed, in consideration of the heterogeneity of the soils, there are difficulties, on the first hand on sites during the sampling of the soils, on the other hand in the laboratory during the chemical analysis of the organic pollutants. After having evoked this problematic, the paper accounts for the evaluation, done by GDF, of varied analytical methods, used and even recommended by reference oragnizations (included: preparatation of the samples, extraction of the organic pollutants, analysis of the extract and interpretation). Finally, on the basis of the accumulated experinece, some advice are given on how to optimize the number and the kind of samples as well as the combined analysis. (au)

  7. Soil pH management without lime, a strategy to reduce greenhouse gas emissions from cultivated soils

    Nadeem, Shahid; Bakken, Lars; Reent Köster, Jan; Tore Mørkved, Pål; Simon, Nina; Dörsch, Peter

    2015-04-01

    For decades, agricultural scientists have searched for methods to reduce the climate forcing of food production by increasing carbon sequestration in the soil and reducing the emissions of nitrous oxide (N2O). The outcome of this research is depressingly meagre and the two targets appear incompatible: efforts to increase carbon sequestration appear to enhance the emissions of N2O. Currently there is a need to find alternative management strategies which may effectively reduce both the CO2 and N2O footprints of food production. Soil pH is a master variable in soil productivity and plays an important role in controlling the chemical and biological activity in soil. Recent investigations of the physiology of denitrification have provided compelling evidence that the emission of N2O declines with increasing pH within the range 5-7. Thus, by managing the soil pH at a near neutral level appears to be a feasible way to reduce N2O emissions. Such pH management has been a target in conventional agriculture for a long time, since a near-neutral pH is optimal for a majority of cultivated plants. The traditional way to counteract acidification of agricultural soils is to apply lime, which inevitably leads to emission of CO2. An alternative way to increase the soil pH is the use of mafic rock powders, which have been shown to counteract soil acidification, albeit with a slower reaction than lime. Here we report a newly established field trail in Norway, in which we compare the effects of lime and different mafic mineral and rock powders (olivine, different types of plagioclase) on CO2 and N2O emissions under natural agricultural conditions. Soil pH is measured on a monthly basis from all treatment plots. Greenhouse gas (GHG) emission measurements are carried out on a weekly basis using static chambers and an autonomous robot using fast box technique. Field results from the first winter (fallow) show immediate effect of lime on soil pH, and slower effects of the mafic rocks. The

  8. One year continuous soil gas monitoring above an EGR test site

    Furche, Markus; Schlömer, Stefan; Faber, Eckhard; Dumke, Ingolf

    2010-05-01

    Setup and first results of an ongoing research activity are presented, which is funded by the German Geotechnologien program within in the joint project CLEAN (CO2 Large Scale Enhanced Gas Recovery in the Altmark Natural Gas Field). The task is to establish several soil gas monitoring stations above a partly exhausted gas field in the Altmark which will be used for an enhanced gas recovery (EGR) test by injecting CO2 into the reservoir. The aim is to optimize the monitoring technique including automatic data transfer and data exploitation and to understand mechanisms of natural variations of soil gas concentrations in the specific area. Furthermore the suitability of these measurements as a contribution to leakage detection shall be evaluated. A network of 13 gauging stations for the measurement of CO2 is working continuously for about one year. They are spread over an area of 8 x 3 km and are situated in direct vicinity of existing deep boreholes as the most likely locations for possible leakage. In addition one station is placed far outside the gasfield as a reference point. The technique applied to measure soil gas concentrations uses a gas stream circulating in a tube going down a shallow borehole where the circulating gas is in contact with the soil gas phase via a gas permeable membrane. Above surface, moisture is removed from the gas stream before it reaches several gas sensors for CO2. Besides these, several other parameters are determined as well, e.g. soil moisture and soil temperature, water level, gas flow and gas moisture. In addition a meteorological station gives information about precipitation, air humidity, temperature and pressure, global radiation, wind direction and velocity in the area. Data are continuously collected by dataloggers at each station (5 minutes interval), transferred via GSM routers to the BGR server in Hannover and are stored in a specially designed database. The database does not only contain the measurements but also

  9. A Metagenomic Survey of Serpentinites and Nearby Soils in Taiwan

    Li, K. Y.; Hsu, Y. W.; Chen, Y. W.; Huang, T. Y.; Shih, Y. J.; Chen, J. S.; Hsu, B. M.

    2016-12-01

    The serpentinite of Taiwan is originated from the subduction zone of the Eurasian plate and the Philippine Sea plate. Many small bodies of serpentinite are scattered around the lands of the East Rift Valley, which are also one of the major agricultural areas in Taiwan. Since microbial communities play a role both on weathering process and soil recovery, uncovering the microbial compositions in serpentinites and surrounding soils may help people to understand the roles of microorganisms on serpentinites during the nature weathering process. In this study, microorganisms growing on the surface of serpentinites, in the surrounding soil, and agriculture soils that are miles of horizontal distance away from serpentinite were collected. Next generation sequencing (NGS) was carried out to examine the metagenomics of uncultured microbial community in these samples. The metagenomics were further clustered into operational taxonomic units (OTUs) to analyze relative abundance, heatmap of OTUs, and principal coordinates analysis (PCoA). Our data revealed the different types of geographic material had their own distinct structures of microbial community. In serpentinites, the heatmaps based on the phylogenetic pattern showed that the OTUs distributions were similar in phyla of Bacteroidetes, Cyanobacteria, Proteobacteria, Verrucomicrobia, and WPS-1/WPS-2. On the other hand, the heatmaps of phylogenetic pattern of agriculture soils showed that the OTUs distributions in phyla of Chloroflexi, Acidobacteria, Actinobacteria, WPS-1/WPS-2, and Proteobacteria were similar. In soil nearby the serpentinite, some clusters of OTUs in phyla of Bacteroidetes, Cyanobacteria, and WPS-1/WPS-2 have disappeared. Our data provided evidence regarding kinetic evolutions of microbial communities in different geographic materials.

  10. Analysis of benzene, toluene, ethylbenzene and xylenes in soils by headspace and gas chromatography/flame ionization detector

    Jurandir Pereira Pinto

    2006-02-01

    Full Text Available The constituents of gasoline: benzene, toluene, ethylbenzene and xylenes (BTEX are frequently found in soils due to leaks in fuel storage tanks and they present chronic toxicity. In this work it was developed and validated a methodology of BTEX analysis in soil by gas chromatography/ flame ionization detector and static headspace. The recovery of BTEX in soil samples was evaluated using soils with different textures (sandy and loamy. The analysis method showed good resolution, in a low time of analysis (less than 30 minutes. Limits of quantification of 0.05 mg Kg¯¹ soil for benzene, toluene, ethylbenzene and xylenes are below the guiding values that range from 0.15 to 95 mg Kg¯¹ soil, established to determine soil quality. It was verified that the methodology enables the use of this method for BTEX analysis of soil samples for passive environmental identification of gas stations.

  11. Natural gas survey, middle east and North Africa, 2005

    2005-01-01

    This book provides an exhaustive, unrivaled and quarterly updated analysis of the gas industry in the Arab countries and Iran. In addition to the country-by-country reports, it includes a regional overview section on the objectives and priorities of the national companies: ADNOC, EGAS, NIGC, NOC, PDO, QATARGAS, RASGAS, SAUDI ARAMCO, SONATRACH, etc... It includes: 18 country reports, 51 maps illustrating gas fields and facilities, as well as 62 tables and 87 graphs, and 2420 addresses of oil and gas companies operating in the Middle East and North Africa, with contact names, e-mail, phone and fax numbers. Each country report outlines the government policy, reserves, production, field development, foreign companies involved, export schemes, domestic consumption, etc

  12. A national-scale geochemical and mineralogical survey of soils of the conterminous United States

    Smith, David B.; Cannon, William F.; Woodruff, Laurel G.

    2011-01-01

    Highlights: → Sampling for national-scale soil geochemical and mineralogical survey completed for conterminous USA. → Natural variation for most elements is approximately three orders of magnitude. → Composition of soil parent material is the major controlling factor. → Climate (average annual precipitation) is also an important controlling factor for some elements. → Sample archive (4800 sites) available for future investigations. - Abstract: In 2007, the US Geological Survey initiated a low-density (1 site per 1600 km 2 , c. 4800 sites) geochemical and mineralogical survey of soils of the conterminous USA. The ideal sampling protocol at each site includes a sample from 0-5 cm depth, a composite of the soil A horizon, and a sample from the soil C horizon. The 3 , HClO 4 and HF. Separate methods are used for As, Hg, Se and total C on this same size fraction. The major mineralogical components are determined by a quantitative X-ray diffraction method. Sampling was completed in 2010 with chemical and mineralogical analysis currently underway. Preliminary results for a swath from the central USA to Florida clearly show the effects of soil parent material and climate on the chemical and mineralogical composition of soils. A sample archive will be established and made available for future investigations.

  13. Preliminary Monitoring of Soil gas Radon in Potentially Active Faults, San Sai District, Chiang Mai Province, Thailand

    Pondthai, P.; Udphuay, S.

    2013-05-01

    The magnitude of 5.1 Mw earthquake occurred in San Sai District, Chiang Mai Province, Thailand in December 2006 was considered an uncommon event due to the fact that there was no statistical record of such significant earthquake in the area. Therefore the earthquake might have been associated with a potentially active fault zone within the area. The objective of this study is to measure soil gas radon across this unknown fault zone within the Chiang Mai Basin, northern Thailand. Two profiles traversing the expected fault zone of soil gas radon measurements have been monitored, using TASTRAK solid state track nuclear detectors (SSNTDs). Radon signals from three periods of measurement show a distinctive consistent spatial distribution pattern. Anomalous radon areas along the profiles are connected to fault locations previously interpreted from other geophysical survey results. The increased radon signal changes from the radon background level with the signal-to-background ratio above 3 are considered anomalous. Such pattern of radon anomaly supports the existence of the faults. The radon measurement, therefore is a powerful technique in mapping active fault zone.

  14. Annual survey on the natural gas market: results 2012

    Cadin, Didier

    2014-04-01

    While proposing data by tables and graphs, this publication comments the evolution noticed in the natural gas market in 2012. As the French production reaches its end, the share of liquefied natural gas in the national supply and that of purchases have decreased in 2012 after a strong increase in 2011. The natural gas input-output rate decreased for a second year in row. These evolutions are assessed for the different entry points (pipelines or harbours). The evolution of provider countries is also commented: Norway and Russia are the main providers for France. A very close adjustment of resources to demand is highlighted and discussed. The continuous decrease of stocks is also noticed and discussed. After a rather strong increase of natural gas consumption until the middle of the 2000's, this consumption, although it displays some variations, tends to stabilize. The consumption is then analyzed with respect to the sector (energy, agriculture, industry, housing and office building), and to the different French regions

  15. Red soil as a regenerable sorbent for high temperature removal of hydrogen sulfide from coal gas

    Ko, T.-H.; Chu Hsin; Lin, H.-P.; Peng, C.-Y.

    2006-01-01

    In this study, hydrogen sulfide (H 2 S) was removed from coal gas by red soil under high temperature in a fixed-bed reactor. Red soil powders were collected from the northern, center and southern of Taiwan. They were characterized by XRPD, porosity analysis and DCB chemical analysis. Results show that the greater sulfur content of LP red soils is attributed to the higher free iron oxides and suitable sulfidation temperature is around 773 K. High temperature has a negative effect for use red soil as a desulfurization sorbent due to thermodynamic limitation in a reduction atmosphere. During 10 cycles of regeneration, after the first cycle the red soil remained stable with a breakthrough time between 31 and 36 min. Hydrogen adversely affects sulfidation reaction, whereas CO exhibits a positive effect due to a water-shift reaction. COS was formed during the sulfidation stage and this was attributed to the reaction of H 2 S and CO. Results of XRPD indicated that, hematite is the dominant active species in fresh red soil and iron sulfide (FeS) is a product of the reaction between hematite and hydrogen sulfide in red soils. The spinel phase FeAl 2 O 4 was found during regeneration, moreover, the amount of free iron oxides decreased after regeneration indicating the some of the free iron oxide formed a spinel phase, further reducting the overall desulfurization efficiency

  16. [Effects of understory removal on soil greenhouse gas emissions in Carya cathayensis stands].

    Liu, Juan; Chen, Xue-shuang; Wu, Jia-sen; Jiang, Pei-kun; Zhou, Guo-mo; Li, Yong-fu

    2015-03-01

    CO2, N2O and CH4 are important greenhouse gases, and soils in forest ecosystems are their important sources. Carya cathayensis is a unique tree species with seeds used for high-grade dry fruit and oil production. Understory vegetation management plays an important role in soil greenhouse gases emission of Carya cathayensis stands. A one-year in situ experiment was conducted to study the effects of understory removal on soil CO2, N2O and CH4 emissions in C. cathayensis plantation by closed static chamber technique and gas chromatography method. Soil CO2 flux had a similar seasonal trend in the understory removal and preservation treatments, which was high in summer and autumn, and low in winter and spring. N2O emission occurred mainly in summer, while CH4 emission showed no seasonal trend. Understory removal significantly decreased soil CO, emission, increased N2O emission and CH4 uptake, but had no significant effect on soil water soluble organic carbon and microbial biomass carbon. The global warming potential of soil greenhouse gases emitted in the understory removal. treatment was 15.12 t CO2-e . hm-2 a-1, which was significantly lower than that in understory preservation treatment (17.04 t CO2-e . hm-2 . a-1).

  17. Hydropodelogy From the Pedon to the Landscape: Challenges and Accomplishments in the National Cooperative Soil Survey

    Hammer, D.; Richardson, J.; Hempel, J.; Market, P.

    2005-12-01

    American pedology has focused on the National Cooperative Soil Survey. Primary responsibility rests with the U.S. Department of Agriculture. The primary goals, are legislatively mandated, are to map the country's soils, make interpretations, provide information to clients, maintain and market the soil survey. The first goal is near completion and focus is shifting to the other three. Concomitantly, American pedological science is being impacted by several conditions: technological advances; land use changes at unprecedented scales and magnitudes; a burgeoning population increasingly "separated" from the land; and a major emphasis in universities upon biological ("life") sciences at the DNA scale - as if soil, nutrients and water are not life essentials. Effects of the Flood of 1993 and Hurricane Katrina suggest that humans do not understand earth/climate interactions, particularly climatic extremes. Pedologists know the focus on soil classification and mapping was at the expense of understanding processes. Hydropedology is a holistic approach to understanding soil and geomorphic process in order to predict the impacts of perturbations. Water movement on and in the soil is the primary mechanism of distributing and altering sediments and chemicals (pedogenesis), and depends for its success upon understanding that the soil profile is the record of developmental history at that landscape site. Hydropedologists believe soil scientists can use pedons (point data) from appropriate locations from flownets in complex landscapes to extrapolate processes. This is the "pedotransfer function" concept. Technological advances are coupled with the existing soil survey information to create important soil-landscape interpretations at a variety of scales. Early results have been very successful. Quantification of soil systems can be classified broadly into three categories; hard data, soft data and tacit knowledge. "Hard data" are measured numbers, and include such attributes as p

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

    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.

  19. Radiological survey of plants, animals, and soil in micronesia

    Nelson, V.A.

    1975-11-01

    In 1974 the Laboratory of Radiation Ecology began a program to determine the radionuclides found in foods, plants, animals, and soils of the Central Pacific. As part of this program the present study was undertaken to determine radionuclides found in the common foods and soils in areas of Micronesia other than those areas receiving local fallout from the test sites at Bikini or Enewetak atolls. Areas sampled in 1975 were Majuro Atoll in the Marshall Islands, Truk and Ponape in the Caroline Islands, Guam in the Marianas Islands, and Koror and Babelthaup in the Palau Islands. All samples were analyzed for gamma-emitting radionuclides while some were also analyzed for 90 Sr of 239 240 Pu. Results of the analyses indicate that naturally occurring 40 K is the predominant radionuclide in the biological samples. Cesium-137 in amounts less than 1 pCi/g (dry) was the only fallout radionuclide detected in most of the biological samples. Soil samples usually contained 90 Sr, 137 Cs, 238 U, and 239 Pu, while soil from Truk, Palau, and Ponape also contained isotopes of radium and thorium. Soil from Guam also contained 210 Pb and 235 U in addition to the above radionuclides. Considering only the fallout radionuclides, the values for 90 Sr, 137 Cs, and 239 240 Pu in samples from Guam, Palau, Truk, Ponape, and Majuro are less than the values for these radionuclides in similar samples from atolls such as Utirik, Rongerik, and Ailinginae in the northern Marshall Islands, and are much less than values of these radionuclides in samples from Bikini and Rongelap atolls

  20. The impact of soil amendments on greenhouse gas emissions: a comprehensive life cycle assessment approach

    DeLonge, M. S.; Ryals, R.; Silver, W. L.

    2011-12-01

    Soil amendments, such as compost and manure, can be applied to grasslands to improve soil conditions and enhance aboveground net primary productivity. Applying such amendments can also lead to soil carbon (C) sequestration and, when materials are diverted from waste streams (e.g., landfills, manure lagoons), can offset greenhouse gas (GHG) emissions. However, amendment production and application is also associated with GHG emissions, and the net impact of these amendments remains unclear. To investigate the potential for soil amendments to reduce net GHG emissions, we developed a comprehensive, field-scale life cycle assessment (LCA) model. The LCA includes GHG (i.e., CO2, CH4, N2O) emissions of soil amendment production, application, and ecosystem response. Emissions avoided by diverting materials from landfills or manure management systems are also considered. We developed the model using field observations from grazed annual grassland in northern California (e.g., soil C; above- and belowground net primary productivity; C:N ratios; trace gas emissions from soils, manure piles, and composting), CENTURY model simulations (e.g., long-term soil C and trace gas emissions from soils under various land management strategies), and literature values (e.g., GHG emissions from transportation, inorganic fertilizer production, composting, and enteric fermentation). The LCA quantifies and contrasts the potential net GHG impacts of applying compost, manure, and commercial inorganic fertilizer to grazing lands. To estimate the LCA uncertainty, sensitivity tests were performed on the most widely ranging or highly uncertain parameters (e.g., compost materials, landfill emissions, manure management system emissions). Finally, our results are scaled-up to assess the feasibility and potential impacts of large-scale adoption of soil amendment application as a land-management strategy in California. Our base case results indicate that C sinks and emissions offsets associated with

  1. Thermal soil desorption for total petroleum hydrocarbon testing on gas chromatographs

    Mott, J.

    1995-01-01

    Testing for total petroleum hydrocarbons (TPH) is one of the most common analytical tests today. A recent development in chromatography incorporates Thermal Soil Desorption technology to enable analyses of unprepared soil samples for volatiles such as BTEX components and semi-volatiles such as diesel, PCBs, PAHs and pesticides in the same chromatogram, while in the field. A gas chromatograph is the preferred method for determining TPH because the column in a GC separates the individual hydrocarbons compounds such as benzene and toluene from each other and measures each individually. A GC analysis will determine not only the total amount of hydrocarbon, but also whether it is gasoline, diesel or another compound. TPH analysis with a GC is typically conducted with a Flame Ionization Detector (FID). Extensive field and laboratory testing has shown that incorporation of a Thermal Soil Desorber offers many benefits over traditional analytical testing methods such as Headspace, Solvent Extraction, and Purge and Trap. This paper presents the process of implementing Thermal Soil Desorption in gas chromatography, including procedures for, and advantages of faster testing and analysis times, concurrent volatile and semi-volatile analysis, minimized sample manipulation, single gas (H 2 ) operation, and detection to the part-per billion levels

  2. Basic survey project for joint implementation, etc. for associated gas utilization project at Kokdumalak Gas Field in Republic of Uzbekistan

    NONE

    2000-03-01

    For the purpose of reducing greenhouse effect gas emissions, a survey was conducted of the recovery/utilization of the associated gas in the Kokdumalak gas field in the Republic of Uzbekistan. In this area, crude oil and natural gas are produced, but the associated gas, etc. are released burning in the atmospheric air. This plan aims to recover LPG, NGL, etc. from these. In the plan, studies were made on the installation in the Karaulbazar area of production facilities of LPG of 369t/d and NGL of 107t/d by the feed of raw gas of 5,748,000 Sm{sup 3}/d and of LPG storage facilities, and on the installation of a 80km-LPG pipeline. The construction work will start in April, 2001 and is planned to be completed in 33 months. The investment required is estimated at approximately 82,003M US$. The substituting energy generated in this plan will be 168,418 toe/y and will total 5,052,546 toe in the term. Moreover, the reduction in greenhouse effect gas emissions will be 4.52 million t/y in CO2 and will total 135 million t in CO2 in the term. (NEDO)

  3. Lateral gas transport in soil adjacent to an old landfill: factors governing gas migration

    Christophersen, Mette; Kjeldsen, Peter

    2001-01-01

    was observed. There was a good correlation between pressure above the barometric pressure and the methane concentration in the soil, indicating that advective flow was the controlling process. This was confirmed by calculations. Diurnal measurement during a drop in barometric pressure showed that lateral...

  4. Assessing the effectiveness of slab flooring as a barrier to soil gas and radon infiltration

    Williamson, A.D.; Fowler, C.S.; McDonough, S.E.

    1995-01-01

    Experimental studies on the entry of soil gas and radon into slab-on-grade buildings have been carried out in instrumented, single-zone test structures. This work, as part of the Florida Radon Research Program, focused on the effectiveness of slab flooring variants as barriers to soil gas/radon entry. A second objective was the study of the role of subslab fill soil as both a potential source of and barrier to radon entry. Studies were made in well-sealed (∼ 600 mm 2 ELA) unoccupied test buildings placed on well-characterized, radium-bearing sandy fill soil. The buildings were instrumented with data acquisition systems to continuously monitor indoor radon concentrations, differential pressures at several subsurface locations, weather conditions, and soil moisture. The response of the structures to mechanical depressurization as well as natural driving forces was measured. Limited measurements were made regarding direct diffusive transport of radon through apparently intact concrete slabs, as well as transport through cracks in the floor structure

  5. [Determination of lambda-cyhalothrin residue tea and soil using gas chromatography].

    Chen, Linglong; Chen, Jiuxing; Ma, Ming; Chen, Lihua; Yang, Hui; Zhang, Guiqun

    2010-08-01

    A gas chromatographic (GC) method was established for the determination of lambda-cyhalothrin residue in tea and soil. Tea and soil samples were extracted with hexane, separated by capillary column and determined by gas chromatography-electron capture detector (GC-ECD). The average recoveries of lambda-cyhalothrin in tea and soil were 89.0% - 94.1% and 89.8% - 94.7%, respectively at the spiking levels of 0.02 to 2.00 mg/kg. The corresponding relative standard deviations (RSDs, n = 5) were 3.0% -4.9% and 2.5% -4.2%, respectively. The limit of detection (S/N = 3) was 0.002 mg/kg for lambda-cyhalothrin. The degradations of 2.5% lambda-cyhalothrin microemulsion in tea and soil in Changsha, Hunan were investigated and the degradation equations were Y = 3.199 6e(-0.339 4x) and Y = 0.122 4e(-0.103 6x) with the correlation coefficients of 0.995 6 and 0.924 7, respectively. The half-lives of lambda-cyhalothrin in tea and soil were 2.04 days and 6.69 days, respectively.

  6. Dry deposition and soil-air gas exchange of polychlorinated biphenyls (PCBs) in an industrial area.

    Bozlaker, Ayse; Odabasi, Mustafa; Muezzinoglu, Aysen

    2008-12-01

    Ambient air and dry deposition, and soil samples were collected at the Aliaga industrial site in Izmir, Turkey. Atmospheric total (particle+gas) Sigma(41)-PCB concentrations were higher in summer (3370+/-1617 pg m(-3), average+SD) than in winter (1164+/-618 pg m(-3)), probably due to increased volatilization with temperature. Average particulate Sigma(41)-PCBs dry deposition fluxes were 349+/-183 and 469+/-328 ng m(-2) day(-1) in summer and winter, respectively. Overall average particulate deposition velocity was 5.5+/-3.5 cm s(-1). The spatial distribution of Sigma(41)-PCB soil concentrations (n=48) showed that the iron-steel plants, ship dismantling facilities, refinery and petrochemicals complex are the major sources in the area. Calculated air-soil exchange fluxes indicated that the contaminated soil is a secondary source to the atmosphere for lighter PCBs and as a sink for heavier ones. Comparable magnitude of gas exchange and dry particle deposition fluxes indicated that both mechanisms are equally important for PCB movement between air and soil in Aliaga.

  7. Radon occurrence in soil-gas and groundwater around an active landslide

    Ramola, R.C. [Department of Physics, H.N.B. Garhwal University, Badshahi Thaul Campus, Tehri Garhwal -249 199 (India)], E-mail: rcramola@gmail.com; Choubey, V.M. [Wadia Institute of Himalayan Geology, Dehradun 248 001 (India); Negi, M.S.; Prasad, Yogesh; Prasad, Ganesh [Department of Physics, H.N.B. Garhwal University, Badshahi Thaul Campus, Tehri Garhwal -249 199 (India)

    2008-01-15

    This paper presents the results of investigation of radon levels in the soil-gas and groundwater of Uttarkashi, India within the distance of 5 km in vertical and horizontal directions from the landslide of Varunawat hill. Radon release from the soil and groundwater was found higher than the normal values. Radon concentration in groundwater over and around the landslide was found to vary from 0.51 to 86kBqm{sup -3}. The soil-gas radon concentration was found to vary from 219 to 3kBqm{sup -3} along the slope of landslide. Radon exhalation rate in collected soil samples was found to vary from 2.28x10{sup -5} to 9.01x10{sup -5}Bqkg{sup -1}h{sup -1}. Radon values were not found correlated with major and trace element contents in the upper soil of the area, which indicate that the migration of radon from deeper part of the earth along with landslide contribute to the surface radon concentration. Recorded values show a close association with local geology and Varunawat eruptions.

  8. Radon occurrence in soil-gas and groundwater around an active landslide

    Ramola, R.C.; Choubey, V.M.; Negi, M.S.; Prasad, Yogesh; Prasad, Ganesh

    2008-01-01

    This paper presents the results of investigation of radon levels in the soil-gas and groundwater of Uttarkashi, India within the distance of 5 km in vertical and horizontal directions from the landslide of Varunawat hill. Radon release from the soil and groundwater was found higher than the normal values. Radon concentration in groundwater over and around the landslide was found to vary from 0.51 to 86kBqm -3 . The soil-gas radon concentration was found to vary from 219 to 3kBqm -3 along the slope of landslide. Radon exhalation rate in collected soil samples was found to vary from 2.28x10 -5 to 9.01x10 -5 Bqkg -1 h -1 . Radon values were not found correlated with major and trace element contents in the upper soil of the area, which indicate that the migration of radon from deeper part of the earth along with landslide contribute to the surface radon concentration. Recorded values show a close association with local geology and Varunawat eruptions

  9. Using repeat electrical resistivity surveys to assess heterogeneity in soil moisture dynamics under contrasting vegetation types

    Dick, Jonathan; Tetzlaff, Doerthe; Bradford, John; Soulsby, Chris

    2018-04-01

    As the relationship between vegetation and soil moisture is complex and reciprocal, there is a need to understand how spatial patterns in soil moisture influence the distribution of vegetation, and how the structure of vegetation canopies and root networks regulates the partitioning of precipitation. Spatial patterns of soil moisture are often difficult to visualise as usually, soil moisture is measured at point scales, and often difficult to extrapolate. Here, we address the difficulties in collecting large amounts of spatial soil moisture data through a study combining plot- and transect-scale electrical resistivity tomography (ERT) surveys to estimate soil moisture in a 3.2 km2 upland catchment in the Scottish Highlands. The aim was to assess the spatio-temporal variability in soil moisture under Scots pine forest (Pinus sylvestris) and heather moorland shrubs (Calluna vulgaris); the two dominant vegetation types in the Scottish Highlands. The study focussed on one year of fortnightly ERT surveys. The surveyed resistivity data was inverted and Archie's law was used to calculate volumetric soil moisture by estimating parameters and comparing against field measured data. Results showed that spatial soil moisture patterns were more heterogeneous in the forest site, as were patterns of wetting and drying, which can be linked to vegetation distribution and canopy structure. The heather site showed a less heterogeneous response to wetting and drying, reflecting the more uniform vegetation cover of the shrubs. Comparing soil moisture temporal variability during growing and non-growing seasons revealed further contrasts: under the heather there was little change in soil moisture during the growing season. Greatest changes in the forest were in areas where the trees were concentrated reflecting water uptake and canopy partitioning. Such differences have implications for climate and land use changes; increased forest cover can lead to greater spatial variability, greater

  10. Survey of Legionella Species Found in Thai Soil

    Tatiana C. Travis

    2012-01-01

    Full Text Available Members of the Gram-negative genus Legionella are typically found in freshwater environments, with the exception of L. longbeachae, which is present in composts and potting mixes. When contaminated aerosols are inhaled, legionellosis may result, typically as either the more serious pneumonia Legionnaires’ disease or the less severe flu-like illness Pontiac fever. It is presumed that all species of the genus Legionella are capable of causing disease in humans. As a followup to a prior clinical study of legionellosis in rural Thailand, indigenous soil samples were collected proximal to cases’ homes and workplaces and tested for the presence of legionellae by culture. We obtained 115 isolates from 22/39 soil samples and used sequence-based methods to identify 12 known species of Legionella represented by 87 isolates.

  11. Subsurface Characterization using Geophysical Seismic Refraction Survey for Slope Stabilization Design with Soil Nailing

    Ashraf Mohamad Ismail, Mohd; Ng, Soon Min; Hazreek Zainal Abidin, Mohd; Madun, Aziman

    2018-04-01

    The application of geophysical seismic refraction for slope stabilization design using soil nailing method was demonstrated in this study. The potential weak layer of the study area is first identify prior to determining the appropriate length and location of the soil nail. A total of 7 seismic refraction survey lines were conducted at the study area with standard procedures. The refraction data were then analyzed by using the Pickwin and Plotrefa computer software package to obtain the seismic velocity profiles distribution. These results were correlated with the complementary borehole data to interpret the subsurface profile of the study area. It has been identified that layer 1 to 3 is the potential weak zone susceptible to slope failure. Hence, soil nails should be installed to transfer the tensile load from the less stable layer 3 to the more stable layer 4. The soil-nail interaction will provide a reinforcing action to the soil mass thereby increasing the stability of the slope.

  12. Longevity of terrestrial Carbon sinks: effects of soil degradation on greenhouse gas emissions

    Kuhn, Nikolaus J.; Berger, Samuel; Kuonen, Samuel

    2013-04-01

    productivity associated with erosion. Areas with high erosion rates and already erosion-induced damages to soil productivity were considered to be closing or closed landscape carbon sinks. The final global assessment indicates that severe soil degradation in Africa, the Americas and Asia carries the risk of closing terrestrial Carbon sinks that currently contribute to an unintended mitigation of greenhouse gas emissions.

  13. Land Use, Land Use History, and Soil Type Affect Soil Greenhouse Gas Fluxes From Agricultural Landscapes of the East African Highlands

    Wanyama, I.; Rufino, M. C.; Pelster, D. E.; Wanyama, G.; Atzberger, C.; van Asten, P.; Verchot, Louis V.; Butterbach-Bahl, K.

    2018-03-01

    This study aims to explain effects of soil textural class, topography, land use, and land use history on soil greenhouse gas (GHG) fluxes in the Lake Victoria region. We measured GHG fluxes from intact soil cores collected in Rakai, Uganda, an area characterized by low-input smallholder (soil cores were air dried and rewetted to water holding capacities (WHCs) of 30, 55, and 80%. Soil CO2, CH4, and N2O fluxes were measured for 48 h following rewetting. Cumulative N2O fluxes were highest from soils under perennial crops and the lowest from soils under annual crops (P soils had lower N2O fluxes than the clay soils (P soil CO2 fluxes were highest from eucalyptus plantations and lowest from annual crops across multiple WHC (P = 0.014 at 30% WHC and P soil cores from the top soil. This study reveals that land use and soil type have strong effects on GHG fluxes from agricultural land in the study area. Field monitoring of fluxes is needed to confirm whether these findings are consistent with what happens in situ.

  14. The use of soil gas as radon source in radon chambers

    Al-Azmi, Darwish

    2009-01-01

    A procedure is described in which soil gas is utilized as an alternative to the 226 Ra source for the supply of the radon gas required to fill a radon chamber where radon-measuring devices are calibrated. The procedure offers opportunities to vary the radon concentration within the chamber around an average value of about 500 Bq/m 3 , which is considered to be sufficient for calibrating indoor radon detectors. The procedure is simple and the radon source does not require radiation protection certification (for import and/or use), unlike the commercially produced standard radioactive ( 226 Ra) sources.

  15. Ecotoxicological assessment of soils of former manufactured gas plant sites: Bioremediation potential and pollutant mobility

    Haeseler, F.; Blanchet, D.; Druelle, V.; Werner, P.; Vandecasteele, J.P.

    1999-01-01

    Analytically well-characterized soils from four different former manufactured gas plants (MGP) sites contaminated by coal tars were used in tests of extensive biodegradation of polycyclic aromatic hydrocarbons (PAHs) in stirred reactors. In all cases, the extent of biodegradation was limited to 80--100% for 2- and 3-ring PAHs, 40--70% for 4-ring PAHs, and below 20% for 5- and 6-ring PAHs. The capacities to transfer pollutants to water were compared for leachates from soils that had or had not undergone biological treatment. Leachate analysis involved determination of PAHs and bacterial tests of acute toxicity (Microtox) and genotoxicity (SOS Chromotest). For some untreated soils, PAH leaching was observed, and positive responses to the Microtox test were well correlated to the concentrations of naphthalene and phenanthrene. Biologically treated soils had lost all capacities for leaching as concluded from PAH determinations and responses to the Microtox test. All soil leachates were devoid of genotoxic effect, in accordance with the low concentrations observed of mutagenic PAHs. The results of this risk-based approach for assessment of MGP soils showed that pollutants remaining after biological treatment were unavailable for further biodegradation and that the extent of leaching had been reduced to the level that it did not represent a significant threat to groundwater

  16. Combining soil and tree-stem flux measurements and soil gas profiles to understand CH4 pathways in Fagus sylvatica forests

    Maier, M.; Macháčová, Kateřina; Lang, F.; Svobodová, Kateřina; Urban, Otmar

    2018-01-01

    Roč. 181, č. 1 (2018), s. 31-35 ISSN 1436-8730 R&D Projects: GA MŠk(CZ) LO1415 Institutional support: RVO:86652079 Keywords : ch4 * soil gas profile * gas flux * co2 * methanogenesis Subject RIV: ED - Physiology OBOR OECD: Plant sciences, botany Impact factor: 2.102, year: 2016

  17. Survey of state regulatory activities on least cost planning for gas utilities

    Goldman, C.A.; Hopkins, M.E.

    1991-04-01

    Integrated resource planning involves the creation of a process in which supply-side and demand-side options are integrated to create a resource mix that reliably satisfies customers' short-term and long-term energy service needs at the lowest cost. Incorporating the concept of meeting customer energy service needs entails a recognition that customers' costs must be considered along with the utility's costs in the economic analysis of energy options. As applied to gas utilities, an integrated resource plan seeks to balance cost and reliability, and should not be interpreted simply as the search for lowest commodity costs. All state commissions were surveyed to assess the current status of gas planning and demand-side management and to identify significant regulatory issues faced by commissions during the next several years. The survey was to determine the extent to which they have undertaken least-cost planning for gas utilities. The survey included the following topics: (1) status of state PUC least-cost planning regulations and practices for gas utilities; (2) type and scope ofnatural gas DSM programs in effect, includeing fuel substitution; (3) economic tests and analysis methods used to evaluate DSM programs; (4) relationship between prudence reviews of gas utility purchasing practices and integrated resource planning; and (5) key regulatory issues facing gas utilities during the next five years. 34 refs., 6 figs., 10 tabs

  18. Comparison of tree coring and soil gas sampling for screening of contaminated sites

    Nielsen, Mette Algreen; Stalder, Marcel; Riis, Charlotte

    and then identify high risk areas. The uptake of BTEX into trees varies to a greater extent with the tree species and the site conditions than chlorinated solvents, which lead to greater uncertainty. Both methods have their advantages and disadvantages. Hence, the methods supplement each other. Based on results......Site characterization is often time consuming and a financial burden for the site owners, which raises a demand for rapid and inexpensive (pre)screening methods. Phytoscreening by tree coring has shown to be a useful tool to detect subsurface contamination, especially of chlorinated solvents...... suitable as initial screening methods for site characterization. The aim of this study is to compare tree coring and soil gas sampling to evaluate to which extent tree coring may supplement or substitute soil gas sampling as a site contaminant screening tool. And where both methods are feasible, evaluate...

  19. Spatial Variations of Soil Gas Geochemistry in the Tangshan Area of Northern China

    Ying Li

    2013-01-01

    Full Text Available The concentrations of Hg, Rn, H2, He and CO2 in soil gases at 756 sites were measured in the Tangshan area where Ms 7.8 earthquake occurred in 1976 and is characterized by complex tectonic structures and high seismic hazard. The results showed that, spatial variations of the gaseous anomalies, especially hydrogen and helium have spatial congruence along the tectonic lines, which can be attributed to their deep sources and the migration paths formed by the faults. A better congruence of radon and carbon dioxide is highlighted which indicates that carbon dioxide acts as the carrier gas for radon in this area. Two geochemical anomaly zones of soil gas were found in the area wherein all the studied gases exhibited anomalies or high values, related to the faults and earthquakes.

  20. Mapping of Rill Erosion of Arable Soils Based on Unmanned Aerial Vehicles Survey

    Kashtanov, A. N.; Vernyuk, Yu. I.; Savin, I. Yu.; Shchepot'ev, V. V.; Dokukin, P. A.; Sharychev, D. V.; Li, K. A.

    2018-04-01

    Possibilities of using data obtained from unmanned aerial vehicles for detection and mapping of rill erosion on arable lands are analyzed. Identification and mapping of rill erosion was performed on a key plot with a predominance of arable gray forest soils (Greyzemic Phaeozems) under winter wheat in Tula oblast. This plot was surveyed from different heights and in different periods to determine the reliability of identification of rill erosion on the basis of automated procedures in a GIS. It was found that, despite changes in the pattern of rills during the warm season, only one survey during this season is sufficient for adequate assessment of the area of eroded soils. According to our data, the most reliable identification of rill erosion is based on the aerial survey from the height of 50 m above the soil surface. When the height of the flight is more than 200 m, erosional rills virtually escape identification. The efficiency of identification depends on the type of crops, their status, and time of the survey. The surveys of bare soil surface in periods with maximum possible interval from the previous rain or snowmelt season are most efficient. The results of our study can be used in the systems of remote sensing monitoring of erosional processes on arable fields. Application of multiand hyperspectral cameras can improve the efficiency of monitoring.

  1. Survey of energy resources: focus on shale gas

    NONE

    2010-09-15

    The energy sector around the world is undergoing major changes resulting from increasing competitive pressures and concerns about costs, security of supply and the environment. At the same time, 1.6 billion people, almost a quarter of the world population, do not have access to commercial energy and the need for energy infrastructure investment is huge. The energy challenges are not the same in all regions. While rapidly burgeoning economies in the developing world are focusing on expanding energy access to support their economic growth and provide basic energy services to their citizens, industrialised countries are focusing on securing energy supplies in a competitive environment and in a publicly and environmentally acceptable way. In recent years, shale gas has been making headlines as a potential solution for many of the energy-related challenges, in particular in the United States. A number of studies on shale gas have been conducted, the majority focusing on the assessment of the resource base and the role of emerging technologies, which can significantly increase the current reserve estimates.

  2. Modeling Microbial Processes in EPIC to Estimate Greenhouse Gas Emissions from soils

    Schwab, D. E.; Izaurralde, R. C.; McGill, W. B.; Williams, J. R.; Schmid, E.

    2009-12-01

    Emissions of trace gases (CO2, N2O and CH4) to the atmosphere from managed terrestrial ecosystems have been contributing significantly to the warming of Earth. Trace gas production is dominated by biospheric processes. An improved knowledge of the soil-plant-atmosphere interface is of key importance for understanding trace gas dynamics. In soils, microbial metabolism plays a key role in the release or uptake of trace gases. Here we present work on the biophysical and biogeochemical model EPIC (Environmental Policy/Integrated Climate) to extend its capabilities to simulate CO2 and N2O fluxes in managed and unmanaged ecosystems. Emphasis will be given to recently developed, microbially-based, denitrification and nitrification modules. The soil-atmosphere exchange of trace gases can be measured by using various equipments, but often these measurements exhibit extreme space-time variability. We use hourly time steps to account for the variability induced by small changes in environmental conditions. Soils are often studied as macroscopic systems, although their functions are predominantly controlled at a microscopic level; i.e. the level of the microorganisms. We include these processes to the extent that these are known and can be quantitatively described. We represent soil dynamics mathematically with routines for gas diffusion, Michael Menten processes, electron budgeting and other processes such as uptake and transformations. We hypothesize that maximization of energy capture form scarce substrates using energetic favorable reactions drives evolution and that competitive advantage can result by depriving a competitor from a substrate. This Microbe Model changes concepts of production of N-containing trace gases; it unifies understanding of N oxidation and reduction, predicts production and evolution of trace gases and is consistent with observations of anaerobic ammonium oxidation.

  3. Identification of bound alcohols in soil humic acids by gas chromatography-mass spectrometry

    Berthier , Gersende; Dou , Sen; Peakman , Torren; Lichtfouse , Eric

    2000-01-01

    International audience; Humic acids are complex, partly macromolecular, yellow-brownish substances occurring in soils, waters and sediments. In order to shed some light on their molecular structure, crop humic acids were cleaved by alkaline hydrolysis (KOH). The products were fractionated by thin layer chromatography to give mono-alcohols which were analysed as acetate derivatives by gas chromatography coupled to mass spectrometry. Linear alcohols, sterols, stanols and plant-derived triterpen...

  4. Short-term temporal variations of soil gas radon concentration and comparison of measurement techniques

    Neznal, M.; Matolín, M.; Just, G.; Turek, Karel

    2004-01-01

    Roč. 108, č. 1 (2004), s. 55-63 ISSN 0144-8420 R&D Projects: GA AV ČR KSK2067107; GA AV ČR KSK4055109 Grant - others:Projekt SÚJB(CZ) R/2/2000 Institutional research plan: CEZ:AV0Z1048901 Keywords : radon * soil gas * temporal variations Subject RIV: DL - Nuclear Waste, Radioactive Pollution ; Quality Impact factor: 0.617, year: 2003

  5. Land-Use Change, Soil Process and Trace Gas Fluxes in the Brazilian Amazon Basin

    Melillo, Jerry M.; Steudler, Paul A.

    1997-01-01

    We measured changes in key soil processes and the fluxes of CO2, CH4 and N2O associated with the conversion of tropical rainforest to pasture in Rondonia, a state in the southwest Amazon that has experienced rapid deforestation, primarily for cattle ranching, since the late 1970s. These measurements provide a comprehensive quantitative picture of the nature of surface soil element stocks, C and nutrient dynamics, and trace gas fluxes between soils and the atmosphere during the entire sequence of land-use change from the initial cutting and burning of native forest, through planting and establishment of pasture grass and ending with very old continuously-pastured land. All of our work is done in cooperation with Brazilian scientists at the Centro de Energia Nuclear na Agricultura (CENA) through an extant official bi-lateral agreement between the Marine Biological Laboratory and the University of Sao Paulo, CENA's parent institution.

  6. 100-FR-3 groundwater/soil gas supplemental limited field investigation report

    1996-04-01

    In 1993, a Limited Field Investigation (LFI) was conducted for the 100-FR-3 Operable Unit which identified trichloroethylene (TCE) as a contaminant of potential concern (COPC) (DOE-RL 1994). In groundwater samples collected for the LFI, TCE was detected in well 199-177-1 at a concentration exceeding the U.S. Environmental Protection Agency (EPA) maximum contaminant level (5 μg/L) and Washington State groundwater criteria (3 μg/L). With the concurrence of the EPA and the Washington State Department of Ecology (Ecology), a supplemental LFI was conducted to determine the extent and potential source of TCE groundwater contamination associated with the 100-FR-3 Operable Unit. This report summarizes the activities and results of the groundwater/soil gas supplemental LFI for the 100-FR-3 Operable Unit. The primary objective of this investigation was to assess the lateral distribution of TCE in shallow (3 to 5 ft below the water table) groundwater associated with the 100-FR-3 Operable Unit. The second objective was to assess soil gas (3 to 5 concentrations in the study area in an attempt to identify potential sources of TCE and develop a correlation between soil gas and groundwater concentrations). Finally, the third objective of the investigation was to refine the site conceptual model

  7. Greenhouse gas emissions from managed peat soils: is the IPCC reporting guidance realistic?

    J. Couwenberg

    2011-03-01

    Full Text Available Drainage of peatlands leads to the decomposition of peat, resulting in substantial losses of carbon and nitrogen to the atmosphere. The conservation and restoration of peatlands can provide a major contribution to the mitigation of climate change. Improvements to guidance and capacity for reporting of greenhouse gas emissions from peatlands will be valuable in the context of the current negotiations towards a post-2012 climate agreement. This article evaluates IPCC approaches to greenhouse gas emissions from managed organic (peat soils and presents a summary table comparing IPCC default values with best estimates based on recent literature. Inconsistencies are pointed out with regard to the IPCC definitions of organic soils and climate zones. The 2006 IPCC Guidelines use a definition of organic soil that is not totally consistent with FAO definitions, use climate zones that are not fully compatible, present default CO2 values that are substantially (often an order of magnitude too low, and present a default N2O value for tropical cropland that is also an order of magnitude too low. An update of IPCC default values is desirable. The IPCC Emission Factor Database offers a platform for establishing more accurate emission factors, but so far contains little information about emissions from peat soils.

  8. A global survey of the distribution of free gas in marine sediments

    Fleischer, Peter; Orsi, Tim; Richardson, Michael

    2003-10-01

    Following the work of Aubrey Anderson in the Gulf of Mexico, we have attempted to quantify the global distribution of free gas in shallow marine sediments, and have identified and indexed over one hundred documented cases in the scientific and engineering literature. Our survey confirms previous assumptions, primarily that gas bubbles are ubiquitous in the organic-rich muds of coastal waters and shallow adjacent seas. Acoustic turbidity as recorded during seismo-acoustic surveys is the most frequently cited evidence used to infer the presence of seafloor gas. Biogenic methane predominates within these shallow subbottom deposits. The survey also reveals significant imbalances in the geographic distribution of studies, which might be addressed in the future by accessing proprietary data or local studies with limited distribution. Because of their global prevalence, growing interest in gassy marine sediments is understandable as their presence has profound scientific, engineering and environmental implications.

  9. Radon soil-gas concentration and exhalation from mine tailings dams in South Africa

    Ongori, J.; Lindsay, R. [University of the Western Cape, Department of Physics, Private Bag X17, Bellville 7535 (South Africa); Newman, R. [Stellenbosch University, Department of Physics, Private Bag X1 Matieland 7602 (South Africa); Maleka, P. [iThemba LABS, Department of Nuclear Physics, P. O. Box 722, Somerset West 7129 (South Africa)

    2014-07-01

    In Africa as well as in the world, South Africa plays an important role in the mining industry which dates back almost 120 years. Mining activities in South Africa mainly take place in Gauteng Province. Every year million of tons of rocks are taken from underground, milled and processed to extract gold. The uranium bearing tailings are disposed in dumpsites. These tailings dumps contain considerable amounts of radium ({sup 226}Ra) and have therefore been identified as large sources of radon ({sup 222}Rn). Radon is a noble gas formed by the decay of radium which in turn is derived from the radioactive decay of uranium ({sup 238}U). Radon release from these tailings dumps pose health concerns for the surrounding communities. Radon soil gas concentrations and exhalations from a non-operational mine dump (Kloof) which belongs to Carletonville Gold Field, Witwatersrand, South Africa have been investigated. The continuous radon monitor, the Durridge RAD7 was used to measure {sup 222}Rn soil gas concentration in the tailings dump at five different spots. The radon soil gas concentration levels were measured at depths starting from 30 cm below ground/air interface up to 110 cm at intervals of 20 cm. The concentrations recorded ranged from 26±1 to 472±23 kBq.m{sup -3}. Furthermore, thirty four soil samples were taken from the spots where radon soil gas measurements were measured for laboratory-based measurement using the low background Hyper Pure Germanium (HPGe) gamma-ray detector available at the Environmental Radioactivity Laboratory (ERL), iThemba LABS, Western Cape Province. The soil samples were collected in the depth range 0-30 cm. After analysis the weighted average activity concentrations in the soils samples were 308±7 Bq.kg{sup -1}, 255±5 Bq.kg{sup -1} and 18±1 Bq.kg{sup -1} for {sup 238}U, {sup 40}K and {sup 232}Th, respectively. A number of factors such as the radium activity concentration and its distribution in soil grains, soil grain size, soil porosity

  10. No tillage and liming reduce greenhouse gas emissions from poorly drained agricultural soils in Mediterranean regions

    García-Marco, Sonia; Abalos, Diego; Espejo, Rafael; Vallejo, Antonio; Mariscal-Sancho, Ignacio

    2016-01-01

    No tillage (NT) has been associated to increased N_2O emission from poorly drained agricultural soils. This is the case for soils with a low permeable Bt horizon, which generates a perched water layer after water addition (via rainfall or irrigation) over a long period of time. Moreover, these soils often have problems of acidity and require liming application to sustain crop productivity; changes in soil pH have large implications for the production and consumption of soil greenhouse gas (GHG) emissions. Here, we assessed in a split-plot design the individual and interactive effects of tillage practices (conventional tillage (CT) vs. NT) and liming (Ca-amendment vs. not-amendment) on N_2O and CH_4 emissions from poorly drained acidic soils, over a field experiment with a rainfed triticale crop. Soil mineral N concentrations, pH, temperature, moisture, water soluble organic carbon, GHG fluxes and denitrification capacity were measured during the experiment. Tillage increased N_2O emissions by 68% compared to NT and generally led to higher CH_4 emissions; both effects were due to the higher soil moisture content under CT plots. Under CT, liming reduced N_2O emissions by 61% whereas no effect was observed under NT. Under both CT and NT, CH_4 oxidation was enhanced after liming application due to decreased Al"3"+ toxicity. Based on our results, NT should be promoted as a means to improve soil physical properties and concurrently reduce N_2O and CH_4 emissions. Raising the soil pH via liming has positive effects on crop yield; here we show that it may also serve to mitigate CH_4 emissions and, under CT, abate N_2O emissions. - Highlights: • The effect of tillage and liming on GHG was studied in poorly drained acidic soils. • NT reduced N_2O emissions, global warming potential and greenhouse gases intensity. • Liming reduced N_2O and CH_4 emissions under CT; no effect was observed under NT. • NT and liming provide an opportunity for N_2O and CH_4 mitigation.

  11. No tillage and liming reduce greenhouse gas emissions from poorly drained agricultural soils in Mediterranean regions

    García-Marco, Sonia, E-mail: sonia.garcia@upm.es [Departamento de Química y Tecnología de los Alimentos, E.T.S.I. Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, Ciudad Universitaria, 28040 Madrid (Spain); Abalos, Diego, E-mail: diego.abalosrodriguez@wur.nl [Departamento de Química y Tecnología de los Alimentos, E.T.S.I. Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, Ciudad Universitaria, 28040 Madrid (Spain); Espejo, Rafael, E-mail: rafael.espejo@upm.es [Departamento de Producción Agraria, E.T.S.I. Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, Ciudad Universitaria, 28040 Madrid (Spain); Vallejo, Antonio, E-mail: antonio.vallejo@upm.es [Departamento de Química y Tecnología de los Alimentos, E.T.S.I. Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, Ciudad Universitaria, 28040 Madrid (Spain); Mariscal-Sancho, Ignacio, E-mail: i.mariscal@upm.es [Departamento de Producción Agraria, E.T.S.I. Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, Ciudad Universitaria, 28040 Madrid (Spain)

    2016-10-01

    No tillage (NT) has been associated to increased N{sub 2}O emission from poorly drained agricultural soils. This is the case for soils with a low permeable Bt horizon, which generates a perched water layer after water addition (via rainfall or irrigation) over a long period of time. Moreover, these soils often have problems of acidity and require liming application to sustain crop productivity; changes in soil pH have large implications for the production and consumption of soil greenhouse gas (GHG) emissions. Here, we assessed in a split-plot design the individual and interactive effects of tillage practices (conventional tillage (CT) vs. NT) and liming (Ca-amendment vs. not-amendment) on N{sub 2}O and CH{sub 4} emissions from poorly drained acidic soils, over a field experiment with a rainfed triticale crop. Soil mineral N concentrations, pH, temperature, moisture, water soluble organic carbon, GHG fluxes and denitrification capacity were measured during the experiment. Tillage increased N{sub 2}O emissions by 68% compared to NT and generally led to higher CH{sub 4} emissions; both effects were due to the higher soil moisture content under CT plots. Under CT, liming reduced N{sub 2}O emissions by 61% whereas no effect was observed under NT. Under both CT and NT, CH{sub 4} oxidation was enhanced after liming application due to decreased Al{sup 3+} toxicity. Based on our results, NT should be promoted as a means to improve soil physical properties and concurrently reduce N{sub 2}O and CH{sub 4} emissions. Raising the soil pH via liming has positive effects on crop yield; here we show that it may also serve to mitigate CH{sub 4} emissions and, under CT, abate N{sub 2}O emissions. - Highlights: • The effect of tillage and liming on GHG was studied in poorly drained acidic soils. • NT reduced N{sub 2}O emissions, global warming potential and greenhouse gases intensity. • Liming reduced N{sub 2}O and CH{sub 4} emissions under CT; no effect was observed under NT

  12. Soil-gas monitoring: A tool for fault delineation studies along Hsinhua Fault (Tainan), Southern Taiwan

    Walia, Vivek, E-mail: vivekwalia@rediffmail.com [National Center for Research on Earthquake Engineering, National Applied Research Laboratories, Taipei 106, Taiwan (China); Lin, Shih Jung [National Center for Research on Earthquake Engineering, National Applied Research Laboratories, Taipei 106, Taiwan (China); Fu, Ching Chou; Yang, Tsanyao Frank; Hong, Wei-Li [Department of Geosciences, National Taiwan University, Taipei 106, Taiwan (China); Wen, Kuo-Liang [National Center for Research on Earthquake Engineering, National Applied Research Laboratories, Taipei 106, Taiwan (China)] [Department of Earth Sciences and Institute of Geophysics, National Central University, Jhongli 32054, Taiwan (China); Chen, Cheng-Hong [Department of Geosciences, National Taiwan University, Taipei 106, Taiwan (China)

    2010-04-15

    Many studies have shown the soil gas method to be one of the most reliable investigation tools in the research of earthquake precursory signals and fault delineation. The present research is aimed finding the relationship between soil gas distribution and tectonic systems in the vicinity of the Hsinhua Fault zone in the Tainan area of Southern Taiwan. More than 110 samples were collected along 13 traverses to find the spatial distribution of Rn, He, CO{sub 2} and N{sub 2}. The spatial congruence of all the gases shows that N{sub 2} is the most probable carrier gas of He, whereas CO{sub 2} seems to be a good carrier gas of Rn in this area. From the spatial distribution of Rn, He, CO{sub 2} and N{sub 2} the trace of Hsinhua Fault and neotectonic features can be identified. The spatial distribution of studied gases shows a clear anomalous trend ENE-SWS along the Hsinhua Fault.

  13. Seasonal and spatial variations in Rn-222 and Rn-220 in soil gas, and implications for indoor radon levels

    Sharman, G.

    1992-01-01

    Rn-222 enters dwellings as a component of soil gas drawn from the soil by mass flow driven by the pressure difference between the house and soil beneath. In a site on Northampton Sand Ironstone (Aalenian), a preferred path of emanation (hotspot) was found. A difference of 63 Bq L -1 Rn-222 was recorded in July between this point and another 3 m away. Rn-222 in this hotspot shows 12% less variation annually than the surrounding rock. During winter, Rn-222 values within 1.6 m of the house were 44% lower than those at more than 4 m away. Rn-222 showed a 99.5% negative correlation with wind run, showing that on this soil wind pressure can significantly reduce radon in the soil at 500 mm depth. Rn-220 in soil gas correlated positively at the 99.5% level with grass and air temperatures. Rn-220 was not associated with the hotspot. (Author)

  14. Soil-gas diffusivity fingerprints of the dual porosity system in fractured limestone

    Claes, Niels; Chamindu, D.T.K.K.; Jensen, Jacob Birk

    2010-01-01

    processes are mostly limited to hydrogeological (water and solute) transport studies with very poor attention to the gaseous phase transport studies (Kristensen et al. 2010). This study characterizes fractured limestone soils for gas diffusion based on three different gas diffusivity fingerprints. The first...... fingerprint is a two-parameter exponential model, which mainly describes the gas diffusivity in the limestone matrix while taking both fracture connectivity and matrix pore connectivity into account. With the second fingerprint, we make a close observation of the tortuous matrix pore network by means...... of a modified Buckingham (1904) pore connectivity factor (X*). The third fingerprint of the fracture network involves the average angle of diffusion α (Moldrup et al. 2010), a parameter which characterizes the average angle at which the fractures are penetrating the sample....

  15. Estimation of net greenhouse gas balance using crop- and soil-based approaches: Two case studies

    Huang, Jianxiong; Chen, Yuanquan; Sui, Peng; Gao, Wansheng

    2013-01-01

    The net greenhouse gas balance (NGHGB), estimated by combining direct and indirect greenhouse gas (GHG) emissions, can reveal whether an agricultural system is a sink or source of GHGs. Currently, two types of methods, referred to here as crop-based and soil-based approaches, are widely used to estimate the NGHGB of agricultural systems on annual and seasonal crop timescales. However, the two approaches may produce contradictory results, and few studies have tested which approach is more reliable. In this study, we examined the two approaches using experimental data from an intercropping trial with straw removal and a tillage trial with straw return. The results of the two approaches provided different views of the two trials. In the intercropping trial, NGHGB estimated by the crop-based approach indicated that monocultured maize (M) was a source of GHGs (− 1315 kg CO 2 −eq ha −1 ), whereas maize–soybean intercropping (MS) was a sink (107 kg CO 2 −eq ha −1 ). When estimated by the soil-based approach, both cropping systems were sources (− 3410 for M and − 2638 kg CO 2 −eq ha −1 for MS). In the tillage trial, mouldboard ploughing (MP) and rotary tillage (RT) mitigated GHG emissions by 22,451 and 21,500 kg CO 2 −eq ha −1 , respectively, as estimated by the crop-based approach. However, by the soil-based approach, both tillage methods were sources of GHGs: − 3533 for MP and − 2241 kg CO 2 −eq ha −1 for RT. The crop-based approach calculates a GHG sink on the basis of the returned crop biomass (and other organic matter input) and estimates considerably more GHG mitigation potential than that calculated from the variations in soil organic carbon storage by the soil-based approach. These results indicate that the crop-based approach estimates higher GHG mitigation benefits compared to the soil-based approach and may overestimate the potential of GHG mitigation in agricultural systems. - Highlights: • Net greenhouse gas balance (NGHGB) of

  16. Regional soil erosion assessment based on a sample survey and geostatistics

    S. Yin

    2018-03-01

    Full Text Available Soil erosion is one of the most significant environmental problems in China. From 2010 to 2012, the fourth national census for soil erosion sampled 32 364 PSUs (Primary Sampling Units, small watersheds with the areas of 0.2–3 km2. Land use and soil erosion controlling factors including rainfall erosivity, soil erodibility, slope length, slope steepness, biological practice, engineering practice, and tillage practice for the PSUs were surveyed, and the soil loss rate for each land use in the PSUs was estimated using an empirical model, the Chinese Soil Loss Equation (CSLE. Though the information collected from the sample units can be aggregated to estimate soil erosion conditions on a large scale; the problem of estimating soil erosion condition on a regional scale has not been addressed well. The aim of this study is to introduce a new model-based regional soil erosion assessment method combining a sample survey and geostatistics. We compared seven spatial interpolation models based on the bivariate penalized spline over triangulation (BPST method to generate a regional soil erosion assessment from the PSUs. Shaanxi Province (3116 PSUs in China was selected for the comparison and assessment as it is one of the areas with the most serious erosion problem. Ten-fold cross-validation based on the PSU data showed the model assisted by the land use, rainfall erosivity factor (R, soil erodibility factor (K, slope steepness factor (S, and slope length factor (L derived from a 1 : 10 000 topography map is the best one, with the model efficiency coefficient (ME being 0.75 and the MSE being 55.8 % of that for the model assisted by the land use alone. Among four erosion factors as the covariates, the S factor contributed the most information, followed by K and L factors, and R factor made almost no contribution to the spatial estimation of soil loss. The LS factor derived from 30 or 90 m Shuttle Radar Topography Mission

  17. Regional soil erosion assessment based on a sample survey and geostatistics

    Yin, Shuiqing; Zhu, Zhengyuan; Wang, Li; Liu, Baoyuan; Xie, Yun; Wang, Guannan; Li, Yishan

    2018-03-01

    Soil erosion is one of the most significant environmental problems in China. From 2010 to 2012, the fourth national census for soil erosion sampled 32 364 PSUs (Primary Sampling Units, small watersheds) with the areas of 0.2-3 km2. Land use and soil erosion controlling factors including rainfall erosivity, soil erodibility, slope length, slope steepness, biological practice, engineering practice, and tillage practice for the PSUs were surveyed, and the soil loss rate for each land use in the PSUs was estimated using an empirical model, the Chinese Soil Loss Equation (CSLE). Though the information collected from the sample units can be aggregated to estimate soil erosion conditions on a large scale; the problem of estimating soil erosion condition on a regional scale has not been addressed well. The aim of this study is to introduce a new model-based regional soil erosion assessment method combining a sample survey and geostatistics. We compared seven spatial interpolation models based on the bivariate penalized spline over triangulation (BPST) method to generate a regional soil erosion assessment from the PSUs. Shaanxi Province (3116 PSUs) in China was selected for the comparison and assessment as it is one of the areas with the most serious erosion problem. Ten-fold cross-validation based on the PSU data showed the model assisted by the land use, rainfall erosivity factor (R), soil erodibility factor (K), slope steepness factor (S), and slope length factor (L) derived from a 1 : 10 000 topography map is the best one, with the model efficiency coefficient (ME) being 0.75 and the MSE being 55.8 % of that for the model assisted by the land use alone. Among four erosion factors as the covariates, the S factor contributed the most information, followed by K and L factors, and R factor made almost no contribution to the spatial estimation of soil loss. The LS factor derived from 30 or 90 m Shuttle Radar Topography Mission (SRTM) digital elevation model (DEM) data

  18. Assessment of herbicides and organochlorine pesticides contamination in agricultural soils using gas chromatography-mass spectrometry.

    Wang, Wan-Hong; Wang, Shi-Cheng; Wang, Yan-Hong

    2008-01-01

    A rapid multi-residue method for the simultaneous analysis of 3 herbicides and 8 organochlorine pesticides (OCPs) in agricultural soils has been developed, using ultrasonic solvent extraction coupled with gas chromatography-mass spectrometry (GC-MS). The recoveries ranged from 81% to 117% with a relative standard deviation (R.S.D) lower than 15%. The limits of quantification (LOQs) ranged from 0.03 to 1.06 microg x kg(-1) dry weight for different pesticides studied. The proposed method has been applied to investigate the 11 pesticide residues in agricultural soils collected from Liaoning Province, northeast of China. 3 OCPs and 3 herbicides were identified. Acetochlor, atrazine, butachtor were measured in the relatively high level with values ranging from 0.53 to 203.18 microg x kg(-1), 0.14 to 21.20 microg x kg(-1), pesticides in this study was compared with the date of other countries reported and the corresponding limiting values used in Netherland, USA, Canada, Vietnam and Thailand. Among the herbicide residues, there was a significant relativity between soil utilizing types and their residue concentration. It seems that the monitoring action for soil contamination caused by commonly-used herbicides should be enhanced according to soil utilizing types, especially acetochlor in maize field.

  19. A Worldwide Assessment of Greenhouse Gas Emissions from Drained Organic Soils

    Francesco Nicola Tubiello

    2016-04-01

    Full Text Available Despite the importance of organic soils, including peatlands, in the global carbon cycle, detailed information on regional and global emissions is scarce. This is due to the difficulty to map, measure, and assess the complex dynamics of land, soil, and water interactions needed to assess the human-driven degradation of organic soils. We produced a new methodology for the comprehensive assessment of drained organic soils in agriculture and the estimation of the associated greenhouse gas emissions. Results indicated that over 25 million hectares of organic soils were drained worldwide for agriculture use, of which about 60% were in boreal and temperate cool areas, 34% in tropical areas, and 5% in warm temperate areas. Total emissions from the drainage were globally significant, totaling nearly one billion tonnes CO2eq annually. Of this, the CO2 component, about 780 million tonnes, represented more than one-fourth of total net CO2 emissions from agriculture, forestry, and land use. The bulk of these emissions came from a few tropical countries in Southeast Asia, and was linked to land clearing and drainage for crop cultivation. Geospatial data relative to this work were disseminated via the FAO geospatial server GeoNetwork, while the national aggregated statistics were disseminated via the FAOSTAT database.

  20. Composting of biochars improves their sorption properties, retains nutrients during composting and affects greenhouse gas emissions after soil application

    Biochar application to soils has been suggested to elevate nutrient sorption, improve soil fertility and reduce net greenhouse gas (GHG) emissions. We examined the impact of composting biochar together with a biologically active substrate (i.e., livestock manure-straw mixture). We hypothesized that ...

  1. Predicting greenhouse gas emissions and soil carbon from changing pasture to an energy crop.

    Benjamin D Duval

    Full Text Available Bioenergy related land use change would likely alter biogeochemical cycles and global greenhouse gas budgets. Energy cane (Saccharum officinarum L. is a sugarcane variety and an emerging biofuel feedstock for cellulosic bio-ethanol production. It has potential for high yields and can be grown on marginal land, which minimizes competition with grain and vegetable production. The DayCent biogeochemical model was parameterized to infer potential yields of energy cane and how changing land from grazed pasture to energy cane would affect greenhouse gas (CO2, CH4 and N2O fluxes and soil C pools. The model was used to simulate energy cane production on two soil types in central Florida, nutrient poor Spodosols and organic Histosols. Energy cane was productive on both soil types (yielding 46-76 Mg dry mass · ha(-1. Yields were maintained through three annual cropping cycles on Histosols but declined with each harvest on Spodosols. Overall, converting pasture to energy cane created a sink for GHGs on Spodosols and reduced the size of the GHG source on Histosols. This change was driven on both soil types by eliminating CH4 emissions from cattle and by the large increase in C uptake by greater biomass production in energy cane relative to pasture. However, the change from pasture to energy cane caused Histosols to lose 4493 g CO2 eq · m(-2 over 15 years of energy cane production. Cultivation of energy cane on former pasture on Spodosol soils in the southeast US has the potential for high biomass yield and the mitigation of GHG emissions.

  2. Daily changes of radon concentration in soil gas under influence of atmospheric factors: room temperature, soil surface temperature and relative humidity

    Lara, Evelise G.; Oliveira, Arno Heeren de, E-mail: evelise.lara@gmail.com, E-mail: heeren@nuclear.ufmg.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear; Rocha, Zildete; Rios, Francisco Javier, E-mail: rochaz@cdtn.br, E-mail: javier@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2015-07-01

    This work aims at relating the daily change in the radon concentration in soil gas in a Red Yellow Acrisol (SiBCS) under influence of atmospheric factors: room temperature, soil surface temperature and relative humidity. The {sup 226}Ra, {sup 232}Th, U content and permeability were also performed. The measurements of radon soil gas were carried out by using an AlphaGUARD monitor. The {sup 226}Ra activity concentration was made by Gamma Spectrometry (HPGe); the permeability was carried out using the RADON-JOK permeameter and ICP-MS analysis to {sup 232}Th and U content. The soil permeability is 5.0 x 10{sup -12}, which is considered average. The {sup 226}Ra (22.2 ± 0.3 Bq.m{sup -3}); U content (73.4 ± 3.6 Bq.kg{sup -1}) and {sup 232}Th content (55.3 ± 4.0 Bq.kg{sup -1}) were considered above of average concentrations, according to mean values for soils typical (~ 35.0 Bq.kg{sup -1}) by UNSCEAR. The results showed a difference of 26.0% between the highest and the lowest concentration of radon in soil gas: at midnight (15.5 ± 1.0 kBq.m{sup -3}) and 3:00 pm, the highest mean radon concentration (21.0 ± 1.0 kBq.m{sup -3}). The room temperature and surface soil temperature showed equivalent behavior and the surface soil temperature slightly below room temperature during the entire monitoring time. Nevertheless, the relative humidity showed the highest cyclical behavior, showing a higher relationship with the radon concentration in soil gas. (author)

  3. Daily changes of radon concentration in soil gas under influence of atmospheric factors: room temperature, soil surface temperature and relative humidity

    Lara, Evelise G.; Oliveira, Arno Heeren de

    2015-01-01

    This work aims at relating the daily change in the radon concentration in soil gas in a Red Yellow Acrisol (SiBCS) under influence of atmospheric factors: room temperature, soil surface temperature and relative humidity. The 226 Ra, 232 Th, U content and permeability were also performed. The measurements of radon soil gas were carried out by using an AlphaGUARD monitor. The 226 Ra activity concentration was made by Gamma Spectrometry (HPGe); the permeability was carried out using the RADON-JOK permeameter and ICP-MS analysis to 232 Th and U content. The soil permeability is 5.0 x 10 -12 , which is considered average. The 226 Ra (22.2 ± 0.3 Bq.m -3 ); U content (73.4 ± 3.6 Bq.kg -1 ) and 232 Th content (55.3 ± 4.0 Bq.kg -1 ) were considered above of average concentrations, according to mean values for soils typical (~ 35.0 Bq.kg -1 ) by UNSCEAR. The results showed a difference of 26.0% between the highest and the lowest concentration of radon in soil gas: at midnight (15.5 ± 1.0 kBq.m -3 ) and 3:00 pm, the highest mean radon concentration (21.0 ± 1.0 kBq.m -3 ). The room temperature and surface soil temperature showed equivalent behavior and the surface soil temperature slightly below room temperature during the entire monitoring time. Nevertheless, the relative humidity showed the highest cyclical behavior, showing a higher relationship with the radon concentration in soil gas. (author)

  4. Extracting Archaeological Feautres from GPR Surveys Conducted with Variable Soil Moisture Conditions

    Morris, I. M.; Glisic, B.; Gonciar, A.

    2017-12-01

    As a common tool for subsurface archaeological prospection, ground penetrating radar (GPR) is a useful method for increasing the efficiency of archaeological excavations. Archaeological sites are often temporally and financially constrained, therefore having limited ability to reschedule surveys compromised by weather. Furthermore, electromagnetic GPR surveys are especially sensitive to variations in water content, soil type, and site-specific interference. In this work, GPR scans of a partially excavated Roman villa consisting of different construction materials and phases (limestone, andesite, brick) in central Romania are compared. Surveys were conducted with a 500 MHz GPR antenna in both dry (pre-rain event) and wet (post-rain event) conditions. Especially in time or depth slices, wet surveys present additional archaeological features that are not present or clear in the standard dry conditions, while simultaneously masking the clutter present in those scans. When dry, the limestone has a similar dielectric constant to the soil and does not provide enough contrast in electromagnetic properties for strong reflections despite the significant difference in their physical properties. Following precipitation, however, the electromagnetic properties of these two materials is dominated by their respective water content and the contrast is enhanced. For this reason, the wet surveys are particularly necessary for revealing reflections from the limestone features often invisible in dry surveys. GPR surveys conducted in variable environmental conditions provide unique archaeological information, with potential near-surface geophysical applications in nondestructive material characterization and identification.

  5. Soil physical, chemical and gas-flux characterization from Picea mariana stands near Erickson Creek, Alaska

    O'Donnell, Jonathan A.; Harden, Jennifer W.; Manies, Kristen L.

    2011-01-01

    Fire is a particularly important control on the carbon (C) balance of the boreal forest, and fire-return intervals and fire severity appear to have increased since the late 1900s in North America. In addition to the immediate release of stored C to the atmosphere through organic-matter combustion, fire also modifies soil conditions, possibly affecting C exchange between terrestrial and atmospheric pools for decades after the burn. The effects of fire on ecosystem C dynamics vary across the landscape, with topographic position and soil drainage functioning as important controls. The data reported here contributed to a larger U.S. Geological Survey (USGS) study, published in the journal Ecosystems by O'Donnell and others (2009). To evaluate the effects of fire and drainage on ecosystem C dynamics, we selected sample sites within the 2003 Erickson Creek fire scar to measure CO2 fluxes and soil C inventories in burned and unburned (control) sites in both upland and lowland black spruce (Picea mariana) forests. The results of this study suggested that although fire can create soil climate conditions which are more conducive to rapid decomposition, rates of C release from soils may be constrained after fire by changes in moisture and (or) substrate quality that impede rates of decomposition. Here, we report detailed site information, methodology, and data (in spreadsheet files) from that study.

  6. Soil Gas Dynamics and Microbial Activity in the Unsaturated Zone of a Regulated River

    Christensen, H.; Ferencz, S. B.; Cardenas, M. B.; Neilson, B. T.; Bennett, P. C.

    2017-12-01

    Over 60% of the world's rivers are dammed, and are therefore regulated. In some river systems, river regulation is the dominant factor governing fluid exchange and soil gas dynamics in the hyporheic region and overlying unsaturated zone of the river banks. Where this is the case, it is important to understand the effects that an artificially-induced change in river stage can have on the chemical, plant, and microbial components of the unsaturated zone. Daily releases from an upstream dam cause rapid stage fluctuations in the Lower Colorado River east of Austin, Texas. For this study, we utilized an array of water and gas wells along a transect perpendicular to the river to investigate the biogeochemical process occurring in this mixing zone. The gas wells were installed at several depths up to 1.5 meters, and facilitated the continuous monitoring of soil gases as the pulse percolated through the river bank. Water samples collected from the screened wells penetrated to depths below the water table and were analyzed for nutrients, carbon, and major ions. Additionally, two soil cores were taken at different distances from the river and analyzed for soil moisture and grain size. These cores were also analyzed for microbial activity using the total heterotroph count method and the acetylene inhibition technique, a sensitive method of measuring denitrifying activity. The results provide a detailed picture of soil gas flux and biogeochemical processes in the bank environment in a regulated river. Findings indicate that a river pulse that causes a meter-scale change in river stage causes small, centimeter-scale pulses in the water table. We propose that these conditions create an area of elevated microbial respiration at the base of the unsaturated zone that appears to be decoupled from normal diurnal fluctuations. Along the transect, CO2 concentrations increased with increasing depth down to the water table. CO2 concentrations were highest in the time following a pulse

  7. The application of soil-gas geochemistry to precisely locate La Victoria fault near Paracotos (Venezuela)

    LaBrecque, J.J.; Rosales, P.A.; Cordoves, P.R.

    1999-01-01

    Full text: Measurements of radon (total radon, Radon-222 and Radon-220) and other soil-gases (CO 2 , O 2 and H 2 ) were performed routinely during 1998 and 1999 across a narrow valley near Paracotos, Venezuela in an attempt to precisely locate the La Victoria fault. The transect was about 300 meters long with eleven sampling points. The soil-gas probes were inserted to a depth of 45 cm in the beginning and later on completely to a depth of 63 cm. The radon sampling and measurements were accomplished with a Pylon AB-5 radiation monitor and Lucas scintillation cells. The other soil-gases were directly determined with an Anagas, CD95 monitor and an Infra-red Gas Analyzer (MKIIC) both coupled with a Hydrogen pod. The radon values for more than twenty different sampling periods over a two year period resulted with anomalous values between 75 and 150 meters along the transect. There were three consecutive anomalous values each time. But strangely, the anomalies of the radon values were in the form of a doublet at 116 and 141 meters rather than a simple single peak in the middle and the gas flow was similar for the sampling points between 75 and 150 meters. The graph of the relative CO 2 values were usually similar to the radon graphs but in some cases, the anomalous values were seen as a simple single peak and corresponded to the 141 meter sampling point. While the anomalous values of Hydrogen were usually in a form of a single peak that corresponded with 141 meter sampling point. Only a few times were values for Hydrogen higher than 100 ppm and detected at most of the sampling points, usually only one or two points resulted with small values near the 141 meter sampling point. Based on the radon values alone, we would have to conclude that the fault probably lies near or between the 116 and 141 meter sampling points, but with the additional data of the CO 2 and H 2 soil-gases one could say that the fault is probably near the 141 meter sampling point. Thus, we have

  8. Ratiometric Gas Reporting: A Nondisruptive Approach To Monitor Gene Expression in Soils.

    Cheng, Hsiao-Ying; Masiello, Caroline A; Del Valle, Ilenne; Gao, Xiaodong; Bennett, George N; Silberg, Jonathan J

    2018-03-16

    Fluorescent proteins are ubiquitous tools that are used to monitor the dynamic functions of natural and synthetic genetic circuits. However, these visual reporters can only be used in transparent settings, a limitation that complicates nondisruptive measurements of gene expression within many matrices, such as soils and sediments. We describe a new ratiometric gas reporting method for nondisruptively monitoring gene expression within hard-to-image environmental matrices. With this approach, C 2 H 4 is continuously synthesized by ethylene forming enzyme to provide information on viable cell number, and CH 3 Br is conditionally synthesized by placing a methyl halide transferase gene under the control of a conditional promoter. We show that ratiometric gas reporting enables the creation of Escherichia coli biosensors that report on acylhomoserine lactone (AHL) autoinducers used for quorum sensing by Gram-negative bacteria. Using these biosensors, we find that an agricultural soil decreases the bioavailable concentration of a long-chain AHL up to 100-fold. We also demonstrate that these biosensors can be used in soil to nondisruptively monitor AHLs synthesized by Rhizobium leguminosarum and degraded by Bacillus thuringiensis. Finally, we show that this new reporting approach can be used in Shewanella oneidensis, a bacterium that lives in sediments.

  9. The regulatory role of endogenous iron on greenhouse gas emissions under intensive nitrogen fertilization in subtropical soils of China.

    Han, Jiangpei; Shi, Liangsheng; Wang, Yakun; Chen, Zhuowei; Wu, Laosheng

    2018-05-01

    Anaerobic batch experiments were conducted to study the regulatory role of endogenous iron in greenhouse gas emissions under intensive nitrogen fertilization in subtropical soils of China. Fe 2+ , Fe 3+ , and NO 3 - -N dynamics and N 2 O, CH 4 , and CO 2 emissions, as well as the relationships between N fertilizer, endogenous iron, and greenhouse gas emissions were investigated. The emissions of N 2 O increased to different extents from all the test soils by N1 (260 mg N kg -1 ) application compared with N0. After 24 days of anaerobic incubation, the cumulative emissions of N 2 O from red soils in De'an (DR) were significantly higher than that from paddy soils in De'an (DP) and Qujialing (QP) under N1. However, N application enhanced CH 4 and CO 2 emissions from the red soils slightly but inhibited the emissions from paddy soils. The maximal CH 4 and CO 2 emission fluxes occurred in DP soil without N input. Pearson's correlation analysis showed that there were significant correlations (P greenhouse gas emissions mainly through the involvement in denitrification. The proportion of the electrons donated by Fe 2+ used for N 2 O production in denitrification in DP soil was approximately 37.53%. Moreover, positive correlations between Fe 2+ and CH 4 , CO 2 were found in both DR and QP soils, suggesting that endogenous iron might regulate the anaerobic decomposition of organic carbon to CH 4 and CO 2 in the two soils. Soil pH was also an important factor controlling greenhouse gas emissions by affecting endogenous iron availability and C and N transformation processes.

  10. UAV MULTISPECTRAL SURVEY TO MAP SOIL AND CROP FOR PRECISION FARMING APPLICATIONS

    G. Sona

    2016-06-01

    Full Text Available New sensors mounted on UAV and optimal procedures for survey, data acquisition and analysis are continuously developed and tested for applications in precision farming. Procedures to integrate multispectral aerial data about soil and crop and ground-based proximal geophysical data are a recent research topic aimed to delineate homogeneous zones for the management of agricultural inputs (i.e., water, nutrients. Multispectral and multitemporal orthomosaics were produced over a test field (a 100 m x 200 m plot within a maize field, to map vegetation and soil indices, as well as crop heights, with suitable ground resolution. UAV flights were performed in two moments during the crop season, before sowing on bare soil, and just before flowering when maize was nearly at the maximum height. Two cameras, for color (RGB and false color (NIR-RG images, were used. The images were processed in Agisoft Photoscan to produce Digital Surface Model (DSM of bare soil and crop, and multispectral orthophotos. To overcome some difficulties in the automatic searching of matching points for the block adjustment of the crop image, also the scientific software developed by Politecnico of Milan was used to enhance images orientation. Surveys and image processing are described, as well as results about classification of multispectral-multitemporal orthophotos and soil indices.

  11. Application of tracer gas studies in the optimal design of soil vapor extraction systems

    Marley, M.C.; Cody, R.J.; Polonsky, J.D.; Woodward, D.D.; Buterbaugh, G.J.

    1992-01-01

    In the design of an optimal, cost effective vapor extraction system (VE) for the remediation of volatile organic compounds (VOCs), it is necessary to account for heterogeneities in the vadose zone. In some cases, such as those found in relatively homogeneous sands, heterogeneities can be neglected as induced air flow through the subsurface can be considered uniform. The subsurface conditions encountered at many sites (soil/bedrock interfaces, fractured bedrock) will result in preferential subsurface-air flow pathways during the operation of the VES. The use of analytical and numerical compressible fluid flow models calibrated and verified from parameter evaluation tests can be utilized to determine vadose zone permeability tensors in heterogeneous stratifications and can be used to project optimal, full scale VES performance. Model-derived estimations of the effect of uniform and/or preferential air flow pathways on subsurface induced air flow velocities can be enhanced, confirmed utilizing tracer gas studies. A vadose zone tracer gas study entails the injection of an easily detected, preferably inert gas into differing locations within the vadose zone at distances away from the VES extraction well. The VES extraction well is monitored for the detection of the gas. This is an effective field methodology to qualify and quantify the subsurface air flow pathways. It is imperative to gain an understanding of the dynamics of the air flow in the soils and lithologies of each individual site, and design quick and effective methodologies for the characterization of the subsurface to streamline remediation costs and system operations. This paper focuses on the use of compressible fluid flow models and tracer gas studies in the enhancement of the design of vapor extraction systems

  12. Improving risk assessments for manufactured gas plant soils by measuring PAH availability.

    Stroo, Hans F; Nakles, David V; Kreitinger, Joseph P; Loehr, Raymond C; Hawthorne, Steven B; Luthy, Richard G; Holman, Hoi-Ying; LaPierre, Adrienne

    2005-07-01

    Remediation of soils at oil-gas manufactured gas plant (MGP) sites is driven primarily by the human health risks posed by the carcinogenic polycyclic aromatic hydrocarbons (PAHs), particularly benzo[a]pyrene (BaP), that are associated with lampblack residues. Although PAHs on lampblack are tightly sorbed, risk assessments do not account for this reduced availability. A multi-investigator study of 7 oil-gas MGP site soil samples demonstrated that the dermal and ingestion absorption factors are far lower than current default assumptions used in risk assessments. Using these sample-specific absorption factors in standard risk assessment equations increased risk-based cleanup levels by a factor of 72 on average (with a range from 23 to 142 times the default level). The rapidly released fraction of the BaP in each sample, as measured by supercritical fluid extraction, was closely correlated (r2 = 0.96) to these calculated cleanup levels. The weight of evidence developed during this research indicates that the risks posed by PAHs on lampblack are far less than assumed when using default absorption factors and that a tiered evaluation protocol employing chemical analyses, chemical release data, and in vitro bioassays can be used to establish more realistic site-specific criteria.

  13. Soil-atmosphere trace gas exchange in semiarid and arid zones.

    Galbally, Ian E; Kirstine, Wayne V; Meyer, C P Mick; Wang, Ying Ping

    2008-01-01

    A review is presented on trace gas exchange of CH4, CO, N2O, and NOx arising from agriculture and natural sources in the world's semiarid and arid zones due to soil processes. These gases are important contributors to the radiative forcing and the chemistry of the atmosphere. Quantitative information is summarized from the available studies. Between 5 and 40% of the global soil-atmosphere exchange for these gases (CH4, CO, N2O, and NOx) may occur in semiarid and arid zones, but for each of these gases there are fewer than a dozen studies to support the individual estimates, and these are from a limited number of locations. Significant differences in the biophysical and chemical processes controlling these trace gas exchanges are identified through the comparison of semiarid and arid zones with the moist temperate or wet/dry savanna land regions. Therefore, there is a poorly quantified understanding of the contribution of these regions to the global trace gas cycles and atmospheric chemistry. More importantly, there is a poor understanding of the feedback between these exchanges, global change, and regional land use and air pollution issues. A set of research issues is presented.

  14. Effect of byproducts of flue gas desulfurization on the soluble salts composition and chemical properties of sodic soils.

    Jinman Wang

    Full Text Available The byproducts of flue gas desulfurization (BFGD are a useful external source of Ca(2+ for the reclamation of sodic soils because they are comparatively cheap, generally available and have high gypsum content. The ion solution composition of sodic soils also plays an important role in the reclamation process. The effect of BFGD on the soluble salts composition and chemical properties of sodic soils were studied in a soil column experiment. The experiment consisted of four treatments using two different sodic soils (sodic soil I and sodic soil II and two BFGD rates. After the application of BFGD and leaching, the soil soluble salts were transformed from sodic salts containing Na2CO3 and NaHCO3 to neutral salts containing NaCl and Na2SO4. The sodium adsorption ratio (SAR, pH and electrical conductivity (EC decreased at all soil depths, and more significantly in the top soil depth. At a depth of 0-40 cm in both sodic soil I and sodic soil II, the SAR, EC and pH were less than 13, 4 dS m(-1 and 8.5, respectively. The changes in the chemical properties of the sodic soils reflected the changes in the ion composition of soluble salts. Leaching played a key role in the reclamation process and the reclamation effect was positively associated with the amount of leaching. The soil salts did not accumulate in the top soil layer, but there was a slight increase in the middle and bottom soil depths. The results demonstrate that the reclamation of sodic soils using BFGD is promising.

  15. The SAMI Galaxy Survey: gas content and interaction as the drivers of kinematic asymmetry

    Bloom, J. V.; Croom, S. M.; Bryant, J. J.; Schaefer, A. L.; Bland-Hawthorn, J.; Brough, S.; Callingham, J.; Cortese, L.; Federrath, C.; Scott, N.; van de Sande, J.; D'Eugenio, F.; Sweet, S.; Tonini, C.; Allen, J. T.; Goodwin, M.; Green, A. W.; Konstantopoulos, I. S.; Lawrence, J.; Lorente, N.; Medling, A. M.; Owers, M. S.; Richards, S. N.; Sharp, R.

    2018-05-01

    In order to determine the causes of kinematic asymmetry in the Hα gas in the SAMI (Sydney-AAO Multi-object IFS) Galaxy Survey sample, we investigate the comparative influences of environment and intrinsic properties of galaxies on perturbation. We use spatially resolved Hα velocity fields from the SAMI Galaxy Survey to quantify kinematic asymmetry (\\overline{v_asym}) in nearby galaxies and environmental and stellar mass data from the Galaxy And Mass Assembly survey. We find that local environment, measured as distance to nearest neighbour, is inversely correlated with kinematic asymmetry for galaxies with log (M*/M⊙) > 10.0, but there is no significant correlation for galaxies with log (M*/M⊙) < 10.0. Moreover, low-mass galaxies [log (M*/M⊙) < 9.0] have greater kinematic asymmetry at all separations, suggesting a different physical source of asymmetry is important in low-mass galaxies. We propose that secular effects derived from gas fraction and gas mass may be the primary causes of asymmetry in low-mass galaxies. High gas fraction is linked to high σ _m/V (where σm is Hα velocity dispersion and V the rotation velocity), which is strongly correlated with \\overline{v_asym}, and galaxies with log (M*/M⊙) < 9.0 have offset \\overline{σ _m/V} from the rest of the sample. Further, asymmetry as a fraction of dispersion decreases for galaxies with log (M*/M⊙) < 9.0. Gas mass and asymmetry are also inversely correlated in our sample. We propose that low gas masses in dwarf galaxies may lead to asymmetric distribution of gas clouds, leading to increased relative turbulence.

  16. Effects of Irrigating with Treated Oil and Gas Product Water on Crop Biomass and Soil Permeability

    Terry Brown; Jeffrey Morris; Patrick Richards; Joel Mason

    2010-09-30

    Demonstrating effective treatment technologies and beneficial uses for oil and gas produced water is essential for producers who must meet environmental standards and deal with high costs associated with produced water management. Proven, effective produced-water treatment technologies coupled with comprehensive data regarding blending ratios for productive long-term irrigation will improve the state-of-knowledge surrounding produced-water management. Effective produced-water management scenarios such as cost-effective treatment and irrigation will discourage discharge practices that result in legal battles between stakeholder entities. The goal of this work is to determine the optimal blending ratio required for irrigating crops with CBNG and conventional oil and gas produced water treated by ion exchange (IX), reverse osmosis (RO), or electro-dialysis reversal (EDR) in order to maintain the long term physical integrity of soils and to achieve normal crop production. The soils treated with CBNG produced water were characterized with significantly lower SAR values compared to those impacted with conventional oil and gas produced water. The CBNG produced water treated with RO at the 100% treatment level was significantly different from the untreated produced water, while the 25%, 50% and 75% water treatment levels were not significantly different from the untreated water. Conventional oil and gas produced water treated with EDR and RO showed comparable SAR results for the water treatment technologies. There was no significant difference between the 100% treated produced water and the control (river water). The EDR water treatment resulted with differences at each level of treatment, which were similar to RO treated conventional oil and gas water. The 100% treated water had SAR values significantly lower than the 75% and 50% treatments, which were similar (not significantly different). The results of the greenhouse irrigation study found the differences in biomass

  17. Modified design in new construction prevents infiltration of soil gas that carries radon

    Ericson, S.O.; Schmied, H.

    1987-01-01

    Dwellings located on permeable soil with strong exhalation of radon often get a contribution to indoor radon from infiltrating soil gas carrying radon from the ground into the building. 100 dwellings have been built on radon dangerous land with different modifications in design and construction in order to prevent infiltration of radon. Tight construction, ventilated crawl space, ventilation/depressurization of the capillary breaking layer (crushed stone), and mechanical ventilation with heat recovery by air to air heat exchangers or heat pumps have been tested. Added building costs and measured concentration of radon after construction and 3-5 years later are reported. It is concluded that it is possible to build radon protective and radon safe dwellings on any land. The added costs have ranged from zero to 4% of total building costs

  18. Improving the design of amphibian surveys using soil data: A case study in two wilderness areas

    Bowen, K.D.; Beever, E.A.; Gafvert, U.B.

    2009-01-01

    Amphibian populations are known, or thought to be, declining worldwide. Although protected natural areas may act as reservoirs of biological integrity and serve as benchmarks for comparison with unprotected areas, they are not immune from population declines and extinctions and should be monitored. Unfortunately, identifying survey sites and performing long-term fieldwork within such (often remote) areas involves a special set of problems. We used the USDA Natural Resource Conservation Service Soil Survey Geographic (SSURGO) Database to identify, a priori, potential habitat for aquatic-breeding amphibians on North and South Manitou Islands, Sleeping Bear Dunes National Lakeshore, Michigan, and compared the results to those obtained using National Wetland Inventory (NWI) data. The SSURGO approach identified more target sites for surveys than the NWI approach, and it identified more small and ephemeral wetlands. Field surveys used a combination of daytime call surveys, night-time call surveys, and perimeter surveys. We found that sites that would not have been identified with NWI data often contained amphibians and, in one case, contained wetland-breeding species that would not have been found using NWI data. Our technique allows for easy a priori identification of numerous survey sites that might not be identified using other sources of spatial information. We recognize, however, that the most effective site identification and survey techniques will likely use a combination of methods in addition to those described here.

  19. Mathematical modelling of water and gas transport in layered soil covers for coal ash deposits

    Rasmussen, A; Lindgren, M [Kemakta Consultants Co, Stockholm (SE)

    1990-12-17

    In the present work the dry deposition alternative is investigated. In particular the design of soil covers is treated theoretically using mathematical models. The soil cover should primarily act as a barrier against infiltrating water. This is done by having soil cover materials with low permeabilities and sloping covers thereby diverting the infiltrating water in the lateral direction. An important design aspect is that overflow should be avoided since this may cause erosional problems. Thus the design of the cover should allow for lateral water flow within the cover. In the present work we use the computer code TRUST for calculating the flow rates and the moisture contents in two layer covers (till on top of clay) for varying conditions. The calculations so far show that the hydraulic conductivity of the clay layer should be smaller than 10{sup -8} m/s. However, for the simulated longer covers (50 m) a lower hydraulic conductivity gives overflow indicating that better lateral drainage must be provided for. This can be done by increasing the thickness or hydraulic conductivity of the till layer. Simulations for different slopes give little impact, while the hydraulic conductivity of the clay layer is of major importance. Gas transport through the soil cover may be of importance if the waste contains pyrite. In the presence of oxygen and water, pyrite is oxidized producing sulphuric acid. The lowered pH will accelerate the leaching of several heavy metals. The transport rate of gas through a porous material is very sensitive to the water content, decreasing rapidly with increasing water content. In the present work a model, where the unsaturated conditions are accounted for, is outlined. A previously developed method for calculating oxygen transport and oxidation rate of pyrite in connection with mine wastes is generalized from 1D to 2D. A sample calculation illustrates the feasibility of the method. (au) (43 refs.).

  20. Identification of radon anomalies in soil gas using decision trees and neural networks

    Zmazek, B.; Dzeroski, S.; Torkar, D.; Vaupotic, J.; Kobal, I.

    2010-01-01

    The time series of radon ( 222 Rn) concentration in soil gas at a fault, together with the environmental parameters, have been analysed applying two machine learning techniques: (I) decision trees and (II) neural networks, with the aim at identifying radon anomalies caused by seismic events and not simply ascribed to the effect of the environmental parameters. By applying neural networks, 10 radon anomalies were observed for 12 earthquakes, while with decision trees, the anomaly was found for every earthquake, but, undesirably, some anomalies appeared also during periods without earthquakes. (authors)

  1. Radon in a Karstic Region School: Concentrations in Soil Gas and Indoors

    Vaupotic, J.; Kobal, I.; Barisic, D.; Lulic, S.

    1998-01-01

    The school presented in this paper exceeded instantaneous indoor radon concentration of 1000 Bqm -3 , obtained within the Slovene radon programme. Thus, additional measurements were performed and the radiation doses of teachers and pupils estimated. Radon concentrations between 1000 and 3000 Bqm -3 during teaching hours were found and the yearly effective doses from 0.75 to 1.1 mSv for the pupils and from 1.1 to 4.2 mSv for the teachers were calculated. In the soil gas radon and thoron concentration ranging from 70 to 150 kBqm -3 were obtained. The school was mitigated during summer 1998. (author)

  2. Comparison of calculated and measured soil-gas radon concentration and radon exhalation rate

    Neznal, Martin; Neznal, Matej; Jiranek, Martin

    2000-01-01

    The computer model RADON2D for WINDOWS, which makes it possible to estimate the radon exhalation rate from the ground surface and the distribution of soil-gas radon concentration, was tested using a large set of experimental data coming from four reference areas located in regions with different geological structure. A good agreement between calculated and experimental data was observed. In the majority of cases, a correct description of the real situation was obtained using non-modified experimental input data. (author)

  3. Flow modelling for The Construction of The Soil gas ventig systems

    Solecki T.

    2004-09-01

    Full Text Available In 1999 the hydrogeological and geotechnical investigations for construction of the large shopping centre were performed showing not documented landfill site. It was recognized that the area intended for construction of the shopping centre served in the past as an illegal not documented refuse dump. The investigation area was located in the centre of large town of Kraków, Poland. This part of city has a high density of blocks of buildings and service lines. During drilling and sampling activities small explosions were observed in same boreholes. This caused the stopping of the works and forced the investor to perform additional investigations for soil gas quality.

  4. The microbial communities and potential greenhouse gas production in boreal acid sulphate, non-acid sulphate, and reedy sulphidic soils.

    Šimek, Miloslav; Virtanen, Seija; Simojoki, Asko; Chroňáková, Alica; Elhottová, Dana; Krištůfek, Václav; Yli-Halla, Markku

    2014-01-01

    Acid sulphate (AS) soils along the Baltic coasts contain significant amounts of organic carbon and nitrogen in their subsoils. The abundance, composition, and activity of microbial communities throughout the AS soil profile were analysed. The data from a drained AS soil were compared with those from a drained non-AS soil and a pristine wetland soil from the same region. Moreover, the potential production of methane, carbon dioxide, and nitrous oxide from the soils was determined under laboratory conditions. Direct microscopic counting, glucose-induced respiration (GIR), whole cell hybridisation, and extended phospholipid fatty acid (PLFA) analysis confirmed the presence of abundant microbial communities in the topsoil and also in the deepest Cg2 horizon of the AS soil. The patterns of microbial counts, biomass and activity in the profile of the AS soil and partly also in the non-AS soil therefore differed from the general tendency of gradual decreases in soil profiles. High respiration in the deepest Cg2 horizon of the AS soil (5.66 μg Cg(-1)h(-1), as compared to 2.71 μg Cg(-1)h(-1) in a top Ap horizon) is unusual but reasonable given the large amount of organic carbon in this horizon. Nitrous oxide production peaked in the BCgc horizon of the AS and in the BC horizon of the non-AS soil, but the peak value was ten-fold higher in the AS soil than in the non-AS soil (82.3 vs. 8.6 ng Ng(-1)d(-1)). The data suggest that boreal AS soils on the Baltic coast contain high microbial abundance and activity. This, together with the abundant carbon and total and mineral nitrogen in the deep layers of AS soils, may result in substantial gas production. Consequently, high GHG emissions could occur, for example, when the generally high water table is lowered because of arable farming. © 2013.

  5. Role of organic amendment application on greenhouse gas emission from soil

    Thangarajan, Ramya, E-mail: thary008@mymail.unisa.edu.au [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095 (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, Adelaide, SA 5095 (Australia); Bolan, Nanthi S. [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095 (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, Adelaide, SA 5095 (Australia); Tian, Guanglong [Environmental Monitoring and Research Division, Monitoring and Research Dep., Metropolitan Water Reclamation District of Greater Chicago, 6001, Pershing Road, Cicero, IL 60804 (United States); Naidu, Ravi [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095 (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, Adelaide, SA 5095 (Australia); Kunhikrishnan, Anitha [Chemical Safety Division, Department of Agro-Food Safety, National Academy of Agricultural Science,10 Suwon-si, Gyeonggi-do (Korea, Republic of)

    2013-11-01

    Globally, substantial quantities of organic amendments (OAs) such as plant residues (3.8 × 10{sup 9} Mg/yr), biosolids (10 × 10{sup 7} Mg/yr), and animal manures (7 × 10{sup 9} Mg/yr) are produced. Recycling these OAs in agriculture possesses several advantages such as improving plant growth, yield, soil carbon content, and microbial biomass and activity. Nevertheless, OA applications hold some disadvantages such as nutrient eutrophication and greenhouse gas (GHG) emission. Agriculture sector plays a vital role in GHG emission (carbon dioxide— CO{sub 2}, methane— CH{sub 4}, and nitrous oxide— N{sub 2}O). Though CH{sub 4} and N{sub 2}O are emitted in less quantity than CO{sub 2}, they are 21 and 310 times more powerful in global warming potential, respectively. Although there have been reviews on the role of mineral fertilizer application on GHG emission, there has been no comprehensive review on the effect of OA application on GHG emission in agricultural soils. The review starts with the quantification of various OAs used in agriculture that include manures, biosolids, and crop residues along with their role in improving soil health. Then, it discusses four major OA induced-GHG emission processes (i.e., priming effect, methanogenesis, nitrification, and denitrification) by highlighting the impact of OA application on GHG emission from soil. For example, globally 10 × 10{sup 7} Mg biosolids are produced annually which can result in the potential emission of 530 Gg of CH{sub 4} and 60 Gg of N{sub 2}O. The article then aims to highlight the soil, climatic, and OA factors affecting OA induced-GHG emission and the management practices to mitigate the emission. This review emphasizes the future research needs in relation to nitrogen and carbon dynamics in soil to broaden the use of OAs in agriculture to maintain soil health with minimum impact on GHG emission from agriculture. - Highlights: ► A comprehensive overview for the first time on GHG emission from

  6. Temperature response of denitrification rate and greenhouse gas production in agricultural river marginal wetland soils.

    Bonnett, S A F; Blackwell, M S A; Leah, R; Cook, V; O'Connor, M; Maltby, E

    2013-05-01

    Soils are predicted to exhibit significant feedback to global warming via the temperature response of greenhouse gas (GHG) production. However, the temperature response of hydromorphic wetland soils is complicated by confounding factors such as oxygen (O2 ), nitrate (NO3-) and soil carbon (C). We examined the effect of a temperature gradient (2-25 °C) on denitrification rates and net nitrous oxide (N2 O), methane (CH4 ) production and heterotrophic respiration in mineral (Eutric cambisol and Fluvisol) and organic (Histosol) soil types in a river marginal landscape of the Tamar catchment, Devon, UK, under non-flooded and flooded with enriched NO3- conditions. It was hypothesized that the temperature response is dependent on interactions with NO3--enriched flooding, and the physicochemical conditions of these soil types. Denitrification rate (mean, 746 ± 97.3 μg m(-2)  h(-1) ), net N2 O production (mean, 180 ± 26.6 μg m(-2)  h(-1) ) and net CH4 production (mean, 1065 ± 183 μg m(-2)  h(-1) ) were highest in the organic Histosol, with higher organic matter, ammonium and moisture, and lower NO3- concentrations. Heterotrophic respiration (mean, 127 ± 4.6 mg m(-2)  h(-1) ) was not significantly different between soil types and dominated total GHG (CO2 eq) production in all soil types. Generally, the temperature responses of denitrification rate and net N2 O production were exponential, whilst net CH4 production was unresponsive, possibly due to substrate limitation, and heterotrophic respiration was exponential but limited in summer at higher temperatures. Flooding with NO3- increased denitrification rate, net N2 O production and heterotrophic respiration, but a reduction in net CH4 production suggests inhibition of methanogenesis by NO3- or N2 O produced from denitrification. Implications for management and policy are that warming and flood events may promote microbial interactions in soil between distinct microbial communities and increase

  7. Temperature and moisture effects on greenhouse gas emissions from deep active-layer boreal soils

    Bond-Lamberty, Ben; Smith, A. Peyton; Bailey, Vanessa

    2016-12-01

    Rapid climatic changes, rising air temperatures, and increased fires are expected to drive permafrost degradation and alter soil carbon (C) cycling in many high-latitude ecosystems. How these soils will respond to changes in their temperature, moisture, and overlying vegetation is uncertain but critical to understand given the large soil C stocks in these regions. We used a laboratory experiment to examine how temperature and moisture control CO2 and CH4 emissions from mineral soils sampled from the bottom of the annual active layer, i.e., directly above permafrost, in an Alaskan boreal forest. Gas emissions from 30 cores, subjected to two temperatures and either field moisture conditions or experimental drought, were tracked over a 100-day incubation; we also measured a variety of physical and chemical characteristics of the cores. Gravimetric water content was 0.31 ± 0.12 (unitless) at the beginning of the incubation; cores at field moisture were unchanged at the end, but drought cores had declined to 0.06 ± 0.04. Daily CO2 fluxes were positively correlated with incubation chamber temperature, core water content, and percent soil nitrogen. They also had a temperature sensitivity (Q10) of 1.3 and 1.9 for the field moisture and drought treatments, respectively. Daily CH4 emissions were most strongly correlated with percent nitrogen, but neither temperature nor water content was a significant first-order predictor of CH4 fluxes. The cumulative production of C from CO2 was over 6 orders of magnitude higher than that from CH4; cumulative CO2 was correlated with incubation temperature and moisture treatment, with drought cores producing 52-73 % lower C. Cumulative CH4 production was unaffected by any treatment. These results suggest that deep active-layer soils may be sensitive to changes in soil moisture under aerobic conditions, a critical factor as discontinuous permafrost thaws in interior Alaska. Deep but unfrozen high-latitude soils have been shown to be

  8. Level of carbon dioxide diffuse degassing from the ground of Vesuvio: comparison between extensive surveys and inferences on the gas source

    Domenico Granieri

    2013-11-01

    Full Text Available An extensive campaign of diffuse CO2 soil flux was carried out at the cone of Vesuvio in October 2006 with two main objectives: 1 to provide an estimation of CO2 diffusely discharged through the soils in the summit area and 2 to evidence those sectors of the volcano where structural and morphological conditions could favour the gas output. The survey consisted of 502 measurements of soil CO2 flux homogenously distributed over an area of about 1.8 km2. Results of this survey were compared with those obtained during a similar campaign carried out by Frondini et al. in 2000, from which we have taken and reinterpreted a subset of data belonging to the common investigated area. Graphical statistical analysis showed three overlapping populations in both surveys, evidencing the contribution of three different sources feeding the soil CO2 degassing process. The overall CO2 emission pattern of 2006 is coherent with that observed in 2000 and suggests that a value between 120 and 140 t/day of CO2 is representative of the total CO2 discharged by diffuse degassing from the summit area of Vesuvio. The preferential exhaling area lies in the inner crater, whose contribution resulted in 45.3% of the total CO2 emission in 2006 (with 62.8 t/day and in 57.4% (with 70.3 t/day in 2000, although its extension is only 13% of the investigated area. This highly emissive area correlated closely with the structural discontinuities of Vesuvio cone, mainly suggesting that the NW-SE trending tectonic line is actually an active fault leaking deep gas to the bottom of the crater. The drainage action of the fault could be enhanced by the “aspiration” effect of the volcanic conduit.

  9. 1978 National Gas Survey: report to the Federal Energy Regulatory Commission by the Technical Advisory Committee on Finance

    None

    1978-06-01

    An overview is given of the gas industry and its financial problems, which have continued to worsen over the past several years. Actions needed to attract capital and regulatory reforms which are needed are discussed. Causes of inflation are examined. Information on projected capital expenditures of the gas industry are surveyed and evaluated. The gas production, transmission, and distribution sectors are considered separately. (DLC)

  10. Recovery Act. Sub-Soil Gas and Fluid Inclusion Exploration and Slim Well Drilling, Pumpernickel Valley, Nevada

    Fairbank, Brian D. [Nevada Geothermal Power Company, Las Vegas, NV (United States)

    2015-03-27

    Nevada Geothermal Power Company (NGP) was awarded DOE Award DE-EE0002834 in January 2010 to conduct sub-soil gas and fluid inclusion studies and slim well drilling at its Black Warrior Project (now known as North Valley) in Washoe and Churchill Counties, Nevada. The project was designed to apply highly detailed, precise, low-cost subsoil and down-hole gas geochemistry methods from the oil and gas industry to identify upflow zone drilling targets in an undeveloped geothermal prospect. NGP ran into multiple institutional barriers with the Black Warrior project relating to property access and extensive cultural survey requirement. NGP requested that the award be transferred to NGP’s Pumpernickel Valley project, due to the timing delay in obtaining permits, along with additional over-budget costs required. Project planning and permit applications were developed for both the original Black Warrior location and at Pumpernickel. This included obtaining proposals from contractors able to conduct required environmental and cultural surveying, designing the two-meter probe survey methodology and locations, and submitting Notices of Intent and liaising with the Bureau of Land Management to have the two-meter probe work approved. The award had an expiry date of April 30, 2013; however, due to the initial project delays at Black Warrior, and the move of the project from Black Warrior to Pumpernickel, NGP requested that the award deadline be extended. DOE was amenable to this, and worked with NGP to extend the deadline. However, following the loss of the Blue Mountain geothermal power plant in Nevada, NGP’s board of directors changed the company’s mandate to one of cash preservation. NGP was unable to move forward with field work on the Pumpernickel property, or any of its other properties, until additional funding was secured. NGP worked to bring in a project partner to form a joint venture on the property, or to buy the property. This was unsuccessful, and NGP notified

  11. Single and Multi-Date Landsat Classifications of Basalt to Support Soil Survey Efforts

    Jessica J. Mitchell

    2013-10-01

    Full Text Available Basalt outcrops are significant features in the Western United States and consistently present challenges to Natural Resources Conservation Service (NRCS soil mapping efforts. Current soil survey methods to estimate basalt outcrops involve field transects and are impractical for mapping regionally extensive areas. The purpose of this research was to investigate remote sensing methods to effectively determine the presence of basalt rock outcrops. Five Landsat 5 TM scenes (path 39, row 29 over the year 2007 growing season were processed and analyzed to detect and quantify basalt outcrops across the Clark Area Soil Survey, ID, USA (4,570 km2. The Robust Classification Method (RCM using the Spectral Angle Mapper (SAM method and Random Forest (RF classifications was applied to individual scenes and to a multitemporal stack of the five images. The highest performing RCM basalt classification was obtained using the 18 July scene, which yielded an overall accuracy of 60.45%. The RF classifications applied to the same datasets yielded slightly better overall classification rates when using the multitemporal stack (72.35% than when using the 18 July scene (71.13% and the same rate of successfully predicting basalt (61.76% using out-of-bag sampling. For optimal RCM and RF classifications, uncertainty tended to be lowest in irrigated areas; however, the RCM uncertainty map included more extensive areas of low uncertainty that also encompassed forested hillslopes and riparian areas. RCM uncertainty was sensitive to the influence of bright soil reflectance, while RF uncertainty was sensitive to the influence of shadows. Quantification of basalt requires continued investigation to reduce the influence of vegetation, lichen and loess on basalt detection. With further development, remote sensing tools have the potential to support soil survey mapping of lava fields covering expansive areas in the Western United States and other regions of the world with similar

  12. Decision Analysis on Survey and SOil Investigation Problem in Power Engineering Consultant

    Setyaman, Amy Maulany; Sunitiyoso, Yos

    2013-01-01

    The study aims to gather and organize information for decision making against the problems arising in Power Engineering Consultant's survey and soil investigation product due to new policy in production cost efficiency that is implemented in 2012. The study conducted using Kepner and Tragoe's analytical process that consisted of four stages analytical process such as situation analysis, problem analysis, decision making analysis and potential problem analysis. As for the decision making analy...

  13. Denitrification nitrogen gas formation and gene expression in alpine grassland soil as affected by climate change conditions

    Chen, Zhe; Wang, Changhui; Gschwendtner, Silvia; Schloter, Michael; Butterbach-Bahl, Klaus; Dannenmann, Michael

    2013-04-01

    Due to methodological problems, reliable data on soil dinitrogen (N2) emission by denitrification are extremely scarce, and the impacts of climate change on nitrogen (N) gas formation by denitrification and N gas product ratios as well as the underlying microbial drivers remain unclear. We combined the helium-gas-flow-soil-core technique for simultaneously quantification of nitrous oxide (N2O) and N2 emission with the reverse transcript qPCR technology. Our goals were to characterize denitrification dynamics and N gas product ratios in alpine grassland soil as affected by climate change conditions and to evaluate relationships between denitrification gene expression and N gas emission. We used soils from the pre-alpine grassland Terrestrial Environmental Observatory (TERENO), exposed to ambient temperature and precipitation (control treatment), or three years of simulated climate change conditions (increased temperature, reduction of summer precipitation and reduced snow cover). Soils were amended with glucose and nitrate and incubated subsequently at 1) 5°C and 20% oxygen; 2) 5°C and 0% oxygen; 3) 20°C and 0% oxygen until stabilization of N gas emissions in each incubation step. After switching incubation conditions to 0% oxygen and 20°C, N2O emission peaked immediately and declined again, followed by a delayed peak in N2 emission. The dynamics of cnorB gene expression, encoding the reduction of nitric oxide (NO) to N2O, followed the N2O emission pattern, while nosZ gene expression, encoding N2O reduction to N2 followed the course of N2 emission. The mean N2O:N2 ratios were 1.31 + 0.10 and 1.56 + 0.16 for control and climate change treatment respectively, but the denitrification potential was overall lower in climate change treatment. Hence, simulated climate change promoted N2O but lessened N2 emission. This stimulation of N2O was in accordance with increased cnorB gene expression in soil of the climate change treatment. N mass balance calculations revealed

  14. Mobile natural gas leak surveys indicate that two utilities have high false negative rates

    von Fischer, J. C.; Brewer, P. E.; Chamberlain, S.; Gaylord, A.; von Fischer, J.

    2016-12-01

    In the distribution systems that carry natural gas to consumers, leaks need to be discovered for safety reasons and to reduce greenhouse gas emissions. However, few utilities have adopted newer laser-based technologies that have greater sensitivity and precision, and instead rely on "industry standard" equipment that is far less sensitive. In partnership with the Environmental Defense Fund and Google, we mapped natural gas leaks in the domains of two anonymous utilities (Utility "A" and "B") using high sensitivity Picarro methane analyzers in Google Street View Cars. Surprisingly, when we shared these results with utilities, their survey crews were unable to find most of the leaks that our survey indicated (84% in A and 80% in B). To investigate this phenomenon, our team visited a subset of the leaks in each utility domain (n=32 in A and n=30 in B), and worked alongside utility surveyors to search the leak indication area, using a Los Gatos Research ultraportable methane analyzer to pinpoint leak locations. We found evidence of natural gas leaks at 69% and 68% of the locations in Utilities A and B respectively where survey crews had found nothing. We describe this as a "false negative" rate for the utility because the utility survey falsely indicated that there was no leak at these locations. Of these false negatives, 7% (n=2 of 32 in A, n=2 of 30 in B) were determined to be Grade 1 leaks requiring immediate repair due to high safety risk. Instrument sensitivity appears to explain some of the false negative rates. In particular, use of some industry standard equipment appears to have created a false sense of confidence among utility surveyors that leaks were not present. However, there was also evidence of communication failures and that surveyors did not use optimal approaches in their search. Based on these findings, we suggest that: 1) mobile deployment of high-precision methane analyzers can help find more natural gas leaks, and 2) use of some hand-held survey

  15. Managing soil organic carbon in agriculture: the net effect on greenhouse gas emissions

    Marland, Gregg; West, Tristram O.; Schlamadinger, Bernhard; Canella, Lorenza

    2003-01-01

    A change in agricultural practice can increase carbon sequestration in agricultural soils. To know the net effect on greenhouse gas emissions to the atmosphere, however, we consider associated changes in CO 2 emissions resulting from the consumption of fossil fuels, emissions of other greenhouse gases and effects on land productivity and crop yield. We also consider how these factors will evolve over time. A change from conventional tillage to no-till agriculture, based on data for average practice in the U.S.; will result in net carbon sequestration in the soil that averages 337 kg C/ha/yr for the initial 20 yr with a decline to near zero in the following 20 yr, and continuing savings in CO 2 emissions because of reduced use of fossil fuels. The long-term results, considering all factors, can generally be expected to show decreased net greenhouse gas emissions. The quantitative details, however, depend on the site-specific impact of the conversion from conventional to no-till agriculture on agricultural yield and N 2 O emissions from nitrogen fertilizer

  16. Detecting buried radium contamination using soil-gas and surface-flux radon meaurements

    Karp, K.E.

    1988-06-01

    The Technical Measurements Center (TMC) has investigated the effectiveness of using radon soil-gas under surface-flux measurments to locate radium contamination that is buried sufficiently deep to be undetectable by surface gamma methods. At the first test site studied, an indication of a buried source was revealed by mapping anomalous surface-flux and soil-gas concentrations in the near surface overburden. The mapped radon anomalies were found to correspond in rough outline to the shape of the areal extent of the deposit as determined by borehole gamma-ray logs. The 5.9pCi/g radium deposit, buried 2 feet below the surface, went undetected by conventional surface gamma measurements. Similar results were obtained at the second test site where radon and conventional surface gamma measurements were taken in an area having radium concentrations ranging from 13.3 to 341.0 pCi/g at a depth of 4 feet below the surface. The radon methods were found to have a detection limit for buried radium lower than that of the surface gamma methods, as evidenced by the discovery of the 13.3 pCi/g deposit which went undetected by the surface gamma methods. 15 refs., 33 figs., 8 tabs

  17. Mathematical modelling of water and gas transport in layered soil covers for coal ash deposit

    Lindgren, M [Kemakta Consultants Co, Stockholm (SE); Rasmuson, A [Chalmers University of Technology, Goeteborg (SE). Dept. of Chemical Engineering Design

    1991-06-19

    In phase 1 of this study the design of soil covers for deposits of coal ash from energy production was studied with regard to various parameters like: climate, cover slope, hydraulic conductivity of tight layer and length of cover. One of the main results was the relatively large risk for total saturation up to the surface and overflow which may cause surface erosion problems. In the present study two theoretical cases are studied to further elucidate the problem. A case from the phase 1 study is used to illustrate the effect of increased infiltration. Calculations show that total saturation and thereby overflow is achieved when the infiltration is increased by 20% in March, but not when increased by 10% only. This shows that the margin in an acceptable case may be small. A cover treated in phase 1, where totally saturated conditions were obtained, was modified so that two decimeters of the one meter till in its bottom part were exchanged for a drainage layer. It is shown that the effect of this layer is large. A negative side-effect, however, is that gas flow may increase due to the lower saturation of the cover. Calculations were made for a real soil covered mine tailings deposit at Bersbo. This deposit was chosen mainly because it is the only well documented case in Sweden where soil covers are used for securing a deposit, but also because some contradictory results as compared to theory were obtained. Another topic studied in the present work was the influence of a heterogeneous clay layer. For example, a weak zone with a hydraulic conductivity of 10{sup -7} m/s (10{sup -9} m/s for the rest of the clay), covering 0.5 m x 0.5 m of 10 m in length and 5 m in width, will increase the flow through the bottom of the cover with almost 30%. The gas transport through the heterogeneous soil cover was also studied, showing about 5 times increased gas transport rate around the weak zone, but almost no difference about 1 m from the weak zone. (29 figs., 5 tabs., 27 refs.).

  18. Telephone survey to investigate relationships between onychectomy or onychectomy technique and house soiling in cats.

    Gerard, Amanda F; Larson, Mandy; Baldwin, Claudia J; Petersen, Christine

    2016-09-15

    OBJECTIVE To determine whether associations existed between onychectomy or onychectomy technique and house soiling in cats. DESIGN Cross-sectional study. SAMPLE 281 owners of 455 cats in Polk County, Iowa, identified via a list of randomly selected residential phone numbers of cat owners in that region. PROCEDURES A telephone survey was conducted to collect information from cat owners on factors hypothesized a priori to be associated with house soiling, including cat sex, reproductive status, medical history, and onychectomy history. When cats that had undergone onychectomy were identified, data were collected regarding the cat's age at the time of the procedure and whether a carbon dioxide laser (CDL) had been used. Information on history of house soiling behavior (urinating or defecating outside the litter box) was also collected. RESULTS Onychectomy technique was identified as a risk factor for house soiling. Cats for which a non-CDL technique was used had a higher risk of house soiling than cats for which the CDL technique was used. Cats that had undergone onychectomy and that lived in a multicat (3 to 5 cats) household were more than 3 times as likely to have house soiled as were single-housed cats with intact claws. CONCLUSIONS AND CLINICAL RELEVANCE Results of this cross-sectional study suggested that use of the CDL technique for onychectomy could decrease the risk of house soiling by cats relative to the risk associated with other techniques. This and other findings can be used to inform the decisions of owners and veterinarians when considering elective onychectomy for cats.

  19. Development of a Miniaturized and Portable Methane Analyzer for Natural Gas Leak Walking Surveys

    Huang, Y. W.; Leen, J. B.; Gupta, M.; Baer, D. S.

    2016-12-01

    Traditional natural gas leak walking surveys have been conducted with devices that are based on technologies such as flame ionization detector (FID), IR-based spectrometer and IR camera. The sensitivity is typically on the ppm level. The low sensitivity means the device cannot pick up leaks far from it, and more time is spent surveying the area before pinpointing the leak location. A miniaturized methane analyzer has been developed to significantly improve the sensitivity of the device used in walking surveys to detect natural gas leaks at greater distance. ABB/LGR's patented Off-Axis Integrated Cavity Output Spectroscopy (OA-ICOS) is utilized to offer rugged and highly sensitive methane detection in a portable package. The miniaturized package weighs 13.5 lb, with a 4-hour rechargeable battery inside. The precision of the analyzer for methane is 2 ppb at 1 second. The analyzer operates at 10 Hz and its flow response time is 3 seconds for measurements through a 1-meter long sampling wand to registering on the data stream. The data can be viewed in real-time on a tablet or a smartphone. The compact and simplified package of the methane analyzer allows for more efficient walking surveys. It also allows for other applications that require low-power, low-weight and a portable package. We present data from walking surveys to demonstrate its ability to detect methane leaks.

  20. Adult proxy responses to a survey of children's dermal soil contact activities.

    Wong, E Y; Shirai, J H; Garlock, T J; Kissel, J C

    2000-01-01

    Contaminated site cleanup decisions may require estimation of dermal exposures to soil. Telephone surveys represent one means of obtaining relevant activity pattern data. The initial Soil Contact Survey (SCS-I), which primarily gathered information on the activities of adults, was conducted in 1996. Data describing adult behaviors have been previously reported. Results from a second Soil Contact Survey (SCS-II), performed in 1998-1999 and focused on children's activity patterns, are reported here. Telephone surveys were used to query a randomly selected sample of U.S. households. A randomly chosen child, under the age of 18 years, was targeted in each responding household having children. Play activities as well as bathing patterns were investigated to quantify total exposure time, defined as activity time plus delay until washing. Of 680 total survey respondents, 500 (73.5%) reported that their child played outdoors on bare dirt or mixed grass and dirt surfaces. Among these "players," the median reported play frequency was 7 days/week in warm weather and 3 days/week in cold weather. Median play duration was 3 h/day in warm weather and 1 h/day in cold weather. Hand washes were reported to occur a median of 4 times per day in both warm and cold weather months. Bath or shower median frequency was seven times per week in both warm and cold weather. Finally, based on clothing choice data gathered in SCS-I, a median of about 37% of total skin surface is estimated to be exposed during young children's warm weather outdoor play.

  1. Strategies to Optimize Microbially-Mediated Mitigation of Greenhouse Gas Emissions from Landfill Cover Soils

    Jeremy Semrau; Sung-Woo Lee; Jeongdae Im; Sukhwan Yoon; Michael Barcelona

    2010-09-30

    The overall objective of this project, 'Strategies to Optimize Microbially-Mediated Mitigation of Greenhouse Gas Emissions from Landfill Cover Soils' was to develop effective, efficient, and economic methodologies by which microbial production of nitrous oxide can be minimized while also maximizing microbial consumption of methane in landfill cover soils. A combination of laboratory and field site experiments found that the addition of nitrogen and phenylacetylene stimulated in situ methane oxidation while minimizing nitrous oxide production. Molecular analyses also indicated that methane-oxidizing bacteria may play a significant role in not only removing methane, but in nitrous oxide production as well, although the contribution of ammonia-oxidizing archaea to nitrous oxide production can not be excluded at this time. Future efforts to control both methane and nitrous oxide emissions from landfills as well as from other environments (e.g., agricultural soils) should consider these issues. Finally, a methanotrophic biofiltration system was designed and modeled for the promotion of methanotrophic activity in local methane 'hotspots' such as landfills. Model results as well as economic analyses of these biofilters indicate that the use of methanotrophic biofilters for controlling methane emissions is technically feasible, and provided either the costs of biofilter construction and operation are reduced or the value of CO{sub 2} credits is increased, can also be economically attractive.

  2. Characterization of trichloroethylene adsorption onto waste biocover soil in the presence of landfill gas.

    He, Ruo; Su, Yao; Kong, Jiaoyan

    2015-09-15

    Waste biocover soils (WBS) have been demonstrated to have great potential in mitigating trichloroethylene (TCE) emission from landfills, due to the relatively high TCE-degrading capacity. In this study, the characteristics of TCE adsorption on WBS in the presence of the major landfill gas components (i.e., CH4 and CO2) were investigated in soil microcosms. The adsorption isotherm of TCE onto WBS was fitted well with linear model within the TCE concentrations of 7000 ppmv. The adsorption capacity of TCE onto WBS was affected by temperature, soil moisture content and particle size, of which, temperature was the dominant factor. The adsorption capacity of TCE onto the experimental materials increased with the increasing organic matter content. A significantly positive correlation was observed between the adsorption capacity of TCE and the organic matter content of experimental materials that had relatively higher organic content (r = 0.988, P = 0.044). To better understand WBS application in practice, response surface methodology was developed to predict TCE adsorption capacity and emissions through WBS in different landfills in China. These results indicated that WBS had high adsorption capacity of TCE in LFG and temperature should be paid more attention to manipulate WBS to reduce TCE emissions from landfills. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Near-critical and supercritical fluid extraction of polycyclic aromatic hydrocarbons from town gas soil

    Kocher, B.S.; Azzam, F.O.; Cutright, T.J.; Lee, S.

    1995-01-01

    The contamination of soil by hazardous and toxic organic pollutants is an ever-growing problem facing the global community. One particular family of contaminants that are of major importance are polycyclic aromatic hydrocarbons (PAHs). PAHs are the result of coal gasification and high-temperature processes. Sludges from these town gas operations were generally disposed of into unlined pits and left there for eventual biodegradation. However, the high levels of PAH contained in the pits prevented the occurrence of biodegradation. PAH contaminated soil is now considered hazardous and must be cleaned to environmentally acceptable standards. One method for the remediation is extraction with supercritical water. Water in or about its critical region exhibits enhanced solvating power toward most organic compounds. Contaminated soil containing 4% by mass of hydrocarbons was ultra-cleaned in a 300-cm 3 semicontinuous system to an environmentally acceptable standard of less than 200 ppm residual hydrocarbon concentration. The effects of subcritical or supercritical extraction, solvent temperature, pressure, and density have been studied, and the discerning characteristics of this type of fluid have been identified. The efficiencies of subcritical and supercritical extraction have been discussed from a process engineering standpoint

  4. Estimation of soil respiration rates and soil gas isotopic composition for the different land use of Ultisols from Calhoun CZO.

    Cherkinsky, A.; Brecheisen, Z.; Richter, D. D., Jr.; Sheng, H.

    2017-12-01

    CO2 flux from soil is significant in most ecosystems and can account for more than 2/3 of total ecosystem respiration. In many cases CO2 fluxes from soil are estimated using eddy covariance techniques or the classical chamber method with measures of bulk concentrations and isotope composition of CO2. Whereas most of these studies estimate flux from the soil surface, we analyzed its concentration and isotope composition directly in soil profiles down to 8.5m depth. This experiment was conducted in Sumter National Forest in summer of 2016. The samples were collected from 3 different land use history sites: a) reference hardwood stands, mainly of oak and hickory that are taken to be never cultivated; b) cultivated plots, which were also used growing cotton prior to the 1950's but for the last 50 years for growing corn, wheat, legume, sorghum, and sunflowers; c) pine stands, which had been used for growing cotton from beginning of the 19th century and then was abandoned in 1920s and planted with loblolly pine. We have analyzed 3 replicates of each land use. There were measured in the field CO2 and O2 concentration and collected gas samples were analyzed for Δ14C, δ13C and δ18O. CO2 concentration in all types of land use has a maximum about 3m depth, approximately the same depth as the minimum of O2 concentration. Isotope analyses revealed that carbon isotopic composition tend to become lighter with the depth for all three types of land use: in cultivated site it changes from -18%o at 0.5m to -21%o at 5m; in pine site from -22%o to -25%o and in hardwood from-21.5 -24.5%o correspondently, the O2 isotopic composition does not change significantly. Based on analysis of Δ14C the turnover rate of CO2 is getting slower as depth increases. At the first 50 cm the exchange rate is the fastest on cultivated site, likely due to annual tilling, and concentration of 14C is actually equal to atmospheric. However, the turnover rate of Δ14C in soil CO2 slows down significantly as

  5. Large-area Soil Moisture Surveys Using a Cosmic-ray Rover: Approaches and Results from Australia

    Hawdon, A. A.; McJannet, D. L.; Renzullo, L. J.; Baker, B.; Searle, R.

    2017-12-01

    Recent improvements in satellite instrumentation has increased the resolution and frequency of soil moisture observations, and this in turn has supported the development of higher resolution land surface process models. Calibration and validation of these products is restricted by the mismatch of scales between remotely sensed and contemporary ground based observations. Although the cosmic ray neutron soil moisture probe can provide estimates soil moisture at a scale useful for the calibration and validation purposes, it is spatially limited to a single, fixed location. This scaling issue has been addressed with the development of mobile soil moisture monitoring systems that utilizes the cosmic ray neutron method, typically referred to as a `rover'. This manuscript describes a project designed to develop approaches for undertaking rover surveys to produce soil moisture estimates at scales comparable to satellite observations and land surface process models. A custom designed, trailer-mounted rover was used to conduct repeat surveys at two scales in the Mallee region of Victoria, Australia. A broad scale survey was conducted at 36 x 36 km covering an area of a standard SMAP pixel and an intensive scale survey was conducted over a 10 x 10 km portion of the broad scale survey, which is at a scale equivalent to that used for national water balance modelling. We will describe the design of the rover, the methods used for converting neutron counts into soil moisture and discuss factors controlling soil moisture variability. We found that the intensive scale rover surveys produced reliable soil moisture estimates at 1 km resolution and the broad scale at 9 km resolution. We conclude that these products are well suited for future analysis of satellite soil moisture retrievals and finer scale soil moisture models.

  6. Feasibility Study of Soil Quality Survey using Visible and Near Infrared Spectroscopy in Rice Paddy Fields in China

    Hongyi Li

    2014-06-01

    Full Text Available Survey and monitoring of soil quality are needed to prevent soil degradation and are important for sustainable farming and food production. Conventional soil survey involves intensive soil sampling and laboratory analysis, which are time consuming and expensive. Visible and near infrared spectroscopy of soil has proved to be accurate, cheap and robust and has huge potential for survey of soil quality. To test its potential, 327 soil samples were taken from long-term paddy rice fields in four provinces in south of China and covered a wide range of soil types and texture. The samples were air-dried, ground and passed through a 2 mm sieve. They were then scanned by an ASD vis–NIR spectrometer with wavelength range from 350 to 2500 nm. Organic matter (OM, pH, total nitrogen (TN and available nitrogen (N_av were also measured on soil samples to build calibration models and also to validate the models’ accuracy. On the basis of the ratio of prediction deviation (RPD, which is standard deviation (SD of prediction divided by the root mean square error of prediction (RMSEP, the accuracy of leave-one-out cross-validation of soil N_av model was classified very good (RPD=1.96 and soil OM and TN was good (RPD=1.78 and RPD=1.81, respectively. However, the model accuracy of pH was poor due to non-direct soil spectral response for soil pH in vis–NIR spectroscopy. The independent validation results showed excellent accuracy for soil N_av (RPD=3.26, good accuracy for OM and TN (RPD=1.76 and RPD=1.78 and relative poor accuracy for soil pH (RPD=1.27. This feasibility study is encouraging for the application of vis–NIR surveys of soil quality accuracy at regional and national scales; it found good to excellent accuracy for some important soil properties in quality survey.

  7. Survey of modern power plants driven by diesel and gas engines

    Niemi, S [Turku Polytechnic, Turku (Finland)

    1998-12-31

    This report surveys the latest technology of power plants driven by reciprocating internal combustion (IC) engines, from information collected from publications made mainly during the 1990`s. Diesel and gas engines are considered competitive prime movers in power production due mainly to their high full- and part-load brake thermal efficiency, ability to burn different fuels, short construction time and fast start-ups. The market for engine power plants has grown rapidly, with estimated total orders for reciprocating engines of 1 MW output and more reaching the 5000 unit level, (10 GW), between June 1995 and May 1996. Industrialized countries much prefer combined heat and power (CHP) production. Intense interest has been shown in recent years in alternative gas fuels; natural gas appears to be the most promising, but liquid petroleum gas, gas from sewage disposal plants, landfill gas and other biogases, as well as wood gas have also been recognized as other alternatives. Liquid alternatives such as fuels and pyrolysis oil have also been mentioned, in addition to information on coal burning engines. The percentage of gas engines used has increased and different ones are being developed, based on either the traditional spark ignition (SI), dual-fuel technology or the more recent high pressure gas injection system. In cold climates, energy production is largely based on CHP plants. Waste heat is utilized for local, regional or district heating or for industrial uses like drying, heating, cooling etc. Even radiative and convective heat from gen-set surfaces are employed, and boilers are used with exhaust outlet temperatures of below dew point. Combined cycle schemes, including turbo compound systems and steam turbines, are also incorporated into engine power plants in order to increase output and efficiency. Two-stroke, low-speed diesel engine plants show the highest electric efficiencies, with combined cycle plants reaching up to 54 %, while gas engine plants achieved

  8. Survey of modern power plants driven by diesel and gas engines

    Niemi, S. [Turku Polytechnic, Turku (Finland)

    1997-12-31

    This report surveys the latest technology of power plants driven by reciprocating internal combustion (IC) engines, from information collected from publications made mainly during the 1990`s. Diesel and gas engines are considered competitive prime movers in power production due mainly to their high full- and part-load brake thermal efficiency, ability to burn different fuels, short construction time and fast start-ups. The market for engine power plants has grown rapidly, with estimated total orders for reciprocating engines of 1 MW output and more reaching the 5000 unit level, (10 GW), between June 1995 and May 1996. Industrialized countries much prefer combined heat and power (CHP) production. Intense interest has been shown in recent years in alternative gas fuels; natural gas appears to be the most promising, but liquid petroleum gas, gas from sewage disposal plants, landfill gas and other biogases, as well as wood gas have also been recognized as other alternatives. Liquid alternatives such as fuels and pyrolysis oil have also been mentioned, in addition to information on coal burning engines. The percentage of gas engines used has increased and different ones are being developed, based on either the traditional spark ignition (SI), dual-fuel technology or the more recent high pressure gas injection system. In cold climates, energy production is largely based on CHP plants. Waste heat is utilized for local, regional or district heating or for industrial uses like drying, heating, cooling etc. Even radiative and convective heat from gen-set surfaces are employed, and boilers are used with exhaust outlet temperatures of below dew point. Combined cycle schemes, including turbo compound systems and steam turbines, are also incorporated into engine power plants in order to increase output and efficiency. Two-stroke, low-speed diesel engine plants show the highest electric efficiencies, with combined cycle plants reaching up to 54 %, while gas engine plants achieved

  9. Oxidation and cyclization of organics in Mars-like soils during evolved gas analysis

    Navarro-Gonzalez, Rafael; Iñiguez, Enrique; de La Rosa, Jose; McKay, Chris

    , doi:10.1029/2009GL040454. Navarro-González, R., Navarro, K.F., de la Rosa, J., Molina, P., Iñiguez, E., Miranda, L.D., a n Morales, P., Cienfuegos, E., Coll, P., Raulin, F., Amils, R. and McKay, C.P.: 2006. The limitations on organic detection in Mars-like soils by thermal volatilization-gas chromatography-MS and their implications for the Viking results. Proc Natl Acad Sci USA 103, 16089-16094. Navarro-González, R., Iñiguez, E., de la Rosa, J. and McKay, C.P.: 2009, Characterization of a n organics, microorganisms, desert soils and Mars-like soils by thermal volatilization coupled to mass spectrometry and their implications for the search of organics on Mars by Phoenix and future space missions. Astrobiology 9, 703-715, doi: 10.1089/ast.2008.0284.

  10. Comparison of passive soil vapor survey techniques at a Tijeras Arroyo site, Sandia National Laboratories, Albuquerque, New Mexico

    Eberle, C.S.; Wade, W.M.; Tharp, T.; Brinkman, J.

    1996-01-01

    Soil vapor surveys were performed to characterize the approximate location of soil contaminants at a hazardous waste site. The samplers were from two separate companies and a comparison was made between the results of the two techniques. These results will be used to design further investigations at the site

  11. Physiologically available cyanide (PAC) in manufactured gas plant waste and soil samples

    Magee, B.; Taft, A.; Ratliff, W.; Kelley, J.; Sullivan, J.; Pancorbo, O.

    1995-01-01

    Iron-complexed cyanide compounds, such as ferri-ferrocyanide (Prussian Blue), are wastes associated with former manufactured gas plant (MGP) facilities. When tested for total cyanide, these wastes often show a high total cyanide content. Because simple cyanide salts are acutely toxic, cyanide compounds can be the subject of concern. However, Prussian Blue and related species are known to have a low order of human and animal toxicity. Toxicology data on complexed cyanides will be presented. Another issue regarding Prussian Blue and related species is that the total cyanide method does not accurately represent the amount of free cyanide released from these cyanide species. The method involves boiling the sample in an acidic solution under vacuum to force the formation of HCN gas. Thus, Prussian Blue, which is known to be low in toxicity, cannot be properly evaluated with current methods. The Massachusetts Natural Gas Council initiated a program with the Massachusetts Department of Environmental Protection to develop a method that would define the amount of cyanide that is able to be converted into hydrogen cyanide under the pH conditions of the stomach. It is demonstrated that less than 1% of the cyanide present in Prussian Blue samples and soils from MGP sites can be converted to HCN under the conditions of the human stomach. The physiologically available cyanide method has been designed to be executed at a higher temperature for one hour. It is shown that physiologically available cyanide in MGP samples is < 5--15% of total cyanide

  12. Identification of Alternative Vapor Intrusion Pathways Using Controlled Pressure Testing, Soil Gas Monitoring, and Screening Model Calculations.

    Guo, Yuanming; Holton, Chase; Luo, Hong; Dahlen, Paul; Gorder, Kyle; Dettenmaier, Erik; Johnson, Paul C

    2015-11-17

    Vapor intrusion (VI) pathway assessment and data interpretation have been guided by an historical conceptual model in which vapors originating from contaminated soil or groundwater diffuse upward through soil and are swept into a building by soil gas flow induced by building underpressurization. Recent studies reveal that alternative VI pathways involving neighborhood sewers, land drains, and other major underground piping can also be significant VI contributors, even to buildings beyond the delineated footprint of soil and groundwater contamination. This work illustrates how controlled-pressure-method testing (CPM), soil gas sampling, and screening-level emissions calculations can be used to identify significant alternative VI pathways that might go undetected by conventional sampling under natural conditions at some sites. The combined utility of these tools is shown through data collected at a long-term study house, where a significant alternative VI pathway was discovered and altered so that it could be manipulated to be on or off. Data collected during periods of natural and CPM conditions show that the alternative pathway was significant, but its presence was not identifiable under natural conditions; it was identified under CPM conditions when measured emission rates were 2 orders of magnitude greater than screening-model estimates and subfoundation vertical soil gas profiles changed and were no longer consistent with the conventional VI conceptual model.

  13. Historical reconstruction of oil and gas spills during moderate and strong earthquakes and related geochemical surveys in Southern Apennines

    Sciarra, Alessandra; Cantucci, Barbara; Ferrari, Graziano; Pizzino, Luca; Quattrocchi, Fedora

    2016-04-01

    The aim of this study is to contribute to the assessment of natural hazards in a seismically active area of southern Italy through the joint analysis of historical sources and fluid geochemistry. In particular, our studies have been focalized in the Val d'Agri basin, in the Apennines extensional belt, since it hosts the largest oilfield in onshore Europe and normal-fault systems with high seismogenic potential (up to M7). The work was organized into three main themes: 1) literature search aimed at identifying fluid emissions during previous moderate-strong earthquakes; 2) consultation of local and national archives to identify historic local place names correlated to natural fluids emissions; 3) geochemical sampling of groundwater and gas issuing at surface, identified on the basis of the bibliographic sources. A reasoned reading of written documents and available historical data was performed. Moreover, we reworked information reported in historical catalogues, referred to liquid and gas hydrocarbon leakages occurred during seismic events of the past (in a range of magnitude from 5 to 7) in the Southern Apennines (with a particular focus on the Val d'Agri). Special attention was given to the phenomena of geochemical emissions related to major historical earthquakes that took place in the area, most notably that of 16 December 1857 (M = 7). A careful analysis of the Robert Mallet's report, a complete work aimed at describing the social impact and the effects on the environment produced by this earthquake through illustrated maps and diagrams, included several hundred monoscopic and stereoscopic photographs, was done. From archival sources (at national and/or local administrations), "sensitive" sites to the onset of leakage of liquid and gaseous hydrocarbons in the past were identified. A soil-gas survey (22 gas concentrations and flux measurements) and 35 groundwater samplings were carried out in specific sites recognized through the above studies. From a

  14. Spatiotemporal dynamics of phosphorus release, oxygen consumption and greenhouse gas emissions after localised soil amendment with organic fertilisers

    Christel, Wibke; Zhu, Kun; Hoefer, Christoph

    2016-01-01

    processes and fixation in the residue sphere, giving rise to distinct differences in nutrient availability, soil oxygen content and greenhouse gas (GHG) production. In this study we investigated the spatiotemporal dynamics of the reaction of manure solids and manure solids char with soil, focusing...... on their phosphorus (P) availability, as current emphasis on improving societal P efficiency through recycling waste or bio-based fertilisers necessitates a sound understanding of their behaviour. Soil layers amended at a constant P application rate with either pig manure solids or char made from pig manure solids...

  15. Groundwater electrical conductivity and soil radon gas monitoring for earthquake precursory studies in Koyna, India

    Reddy, D.V.; Nagabhushanam, P.

    2011-01-01

    Research highlights: → It is the first hydrochemical precursory study in the Koyna region, India. → Discrete conductivity measurements indicated progressive increase for 4 years. → Strong precursory EC change observed 40 h before the M 5.1 earthquake. → Precursory increase of soil Rn gas 20 days earlier than earthquakes M 4.7 and 5.1. → On-line monitoring of these parameters may help in earthquake forecast. - Abstract: Hourly monitoring of electrical conductivity (EC) of groundwater along with groundwater levels in the 210 m deep boreholes (specially drilled for pore pressure/earthquake studies) and soil Rn gas at 60 cm below ground level in real time, in the Koyna-Warna region (characterized by basaltic rocks, >1500 m thick, and dotted with several sets of fault systems), western India, provided strong precursory signatures in response to two earthquakes (M 4.7 on 14/11/09, and M 5.1 on 12/12/09) that occurred in the study region. The EC measured in Govare well water showed precursory perturbations about 40 h prior to the M 5.1 earthquake and continued further for about 20 h after the earthquake. In response to the M 4.7 earthquake, there were EC perturbations 8 days after the earthquake. In another well (Koyna) which is located 4 km north of Govare well, no precursory signatures were found for the M 4.7 earthquake, while for M 5.1 earthquake, post-seismic precursors were found 18 days after the earthquake. Increased porosity and reduced pressure head accompanied by mixing of a freshwater component from the top zone due to earthquakes are the suggested mechanisms responsible for the observed anomalies in EC. Another parameter, soil Rn gas showed relatively proportional strength signals corresponding to these two earthquakes. In both the cases, the pre-seismic increase in Rn concentration started about 20 days in advance. The co-seismic drop in Rn levels was less by 30% from its peak value for the M 4.7 earthquake and 50% for the M 5.1 earthquake. The Rn

  16. ALLSMOG, the APEX Low-redshift Legacy Survey for MOlecular Gas

    Bothwell, M.; Cicone, C.; Wagg, J.; De Breuck, C..

    2017-09-01

    We report the completion of the APEX Low-redshift Legacy Survey for MOlecular Gas (ALLSMOG), an ESO Large Programme, carried out with the Atacama Pathfinder EXperiment (APEX) between 2013 and 2016. With a total of 327 hours of APEX observing time, we observed the 12CO(2-1) line in 88 nearby low-mass star-forming galaxies. We briefly outline the ALLSMOG goals and design, and describe a few science highlights that have emerged from the survey so far. We outline future work that will ensure that the ALLSMOG dataset continues to provide scientific value in the coming years. ALLSMOG was designed to be a reference legacy survey and as such all reduced data products are publicly available through the ESO Science Archive Phase 3 interface.

  17. Using a spatial and tabular database to generate statistics from terrain and spectral data for soil surveys

    Horvath , E.A.; Fosnight, E.A.; Klingebiel, A.A.; Moore, D.G.; Stone, J.E.; Reybold, W.U.; Petersen, G.W.

    1987-01-01

    A methodology has been developed to create a spatial database by referencing digital elevation, Landsat multispectral scanner data, and digitized soil premap delineations of a number of adjacent 7.5-min quadrangle areas to a 30-m Universal Transverse Mercator projection. Slope and aspect transformations are calculated from elevation data and grouped according to field office specifications. An unsupervised classification is performed on a brightness and greenness transformation of the spectral data. The resulting spectral, slope, and aspect maps of each of the 7.5-min quadrangle areas are then plotted and submitted to the field office to be incorporated into the soil premapping stages of a soil survey. A tabular database is created from spatial data by generating descriptive statistics for each data layer within each soil premap delineation. The tabular data base is then entered into a data base management system to be accessed by the field office personnel during the soil survey and to be used for subsequent resource management decisions.Large amounts of data are collected and archived during resource inventories for public land management. Often these data are stored as stacks of maps or folders in a file system in someone's office, with the maps in a variety of formats, scales, and with various standards of accuracy depending on their purpose. This system of information storage and retrieval is cumbersome at best when several categories of information are needed simultaneously for analysis or as input to resource management models. Computers now provide the resource scientist with the opportunity to design increasingly complex models that require even more categories of resource-related information, thus compounding the problem.Recently there has been much emphasis on the use of geographic information systems (GIS) as an alternative method for map data archives and as a resource management tool. Considerable effort has been devoted to the generation of tabular

  18. Short-term effects of CO2 leakage on the soil bacterial community in a simulated gas leakage scenario.

    Ma, Jing; Zhang, Wangyuan; Zhang, Shaoliang; Zhu, Qianlin; Feng, Qiyan; Chen, Fu

    2017-01-01

    The technology of carbon dioxide (CO 2 ) capture and storage (CCS) has provided a new option for mitigating global anthropogenic emissions with unique advantages. However, the potential risk of gas leakage from CO 2 sequestration and utilization processes has attracted considerable attention. Moreover, leakage might threaten soil ecosystems and thus cannot be ignored. In this study, a simulation experiment of leakage from CO 2 geological storage was designed to investigate the short-term effects of different CO 2 leakage concentration (from 400 g m -2 day -1 to 2,000 g m -2 day -1 ) on soil bacterial communities. A shunt device and adjustable flow meter were used to control the amount of CO 2 injected into the soil. Comparisons were made between soil physicochemical properties, soil enzyme activities, and microbial community diversity before and after injecting different CO 2 concentrations. Increasing CO 2 concentration decreased the soil pH, and the largest variation ranged from 8.15 to 7.29 ( p soil CO 2 concentration increased. The dominant phylum in the soil samples was Proteobacteria , whose proportion rose rapidly from 28.85% to 67.93%. In addition, the proportion of Acidobacteria decreased from 19.64% to 9.29% ( p soil ecosystems.

  19. Natural gas in 1942: Petroleum in 1942: Gravimetric and magnetic geophysical surveys in the gas fields of southwestern Ontario, 1941 and 1942. Annual publication

    Crozier, A R; Brant, A A

    1946-12-31

    Part V of this annual report consists of three separate reports: Natural gas; petroleum; and gravimetric and magnetic geophysical surveys in the gas fields of southwestern Ontario. The natural gas report discusses production and distribution; changes and improvements; consumption and rates; and gas wells and their production. The petroleum report presents information on production and drilling by township; expansion; and petroleum importation and refining operations. The final report discusses causes of anomalies; a discussion of the gravitational results and a discussion of the magnetic results.

  20. Surveying the Dense Gas in Barnard 1 and NGC 1333 from Cloud to Core Scales

    Storm, Shaye; Mundy, Lee; Teuben, Peter; Lee, Katherine; Fernandez-Lopez, Manuel; Looney, Leslie; Rosolowsky, Erik; Classy Collaboration

    2013-07-01

    The CARMA Large Area Star formation Survey (CLASSy) is mapping molecular emission across large areas of the nearby Perseus and Serpens Molecular Clouds. With an angular resolution of 7 arcsec, CLASSy probes dense gas on scales from a few thousand AU to parsecs with CARMA-23 and single-dish observations. The resulting maps of N2H+, HCN, and HCO+ J=1-0 trace the kinematics and structure of the high-density gas in regions covering a wide range of intrinsic star formation activity. This poster presents an overview of three completed CLASSy fields, NGC 1333, Barnard 1, and Serpens Main, and then focuses on the dendrogram analysis that CLASSy is using to characterize the emission structure. We have chosen a dendrogram analysis over traditional clump finding because dendrograms better encode the hierarchical nature of cloud structure and better facilitate analysis of cloud properties across the range of size scales probed by CLASSy. We present a new dendrogram methodology that allows for non-binary mergers of kernels, which results in a gas hierarchy that is more true to limitations of the S/N in the data. The resulting trees from Barnard 1 and NGC 1333 are used to derive physical parameters of the identified gas structures, and to probe the kinematic relationship between gas structures at different spatial scales and evolutionary stages. We derive a flat relation between mean internal turbulence and structure size for the dense gas in both regions, but find a difference between the magnitude of the internal turbulence in regions with and without protostars; the dense gas in the B1 main core and NGC 1333 are characterized by mostly transonic to supersonic turbulence, while the B1 filaments and clumps southwest of the main core have mostly subsonic turbulence. These initial results, along with upcoming work analyzing the completed CLASSy observations, will be used to test current theories for star formation in turbulent molecular clouds.

  1. Benefits of biochar, compost and biochar–compost for soil quality, maize yield and greenhouse gas emissions in a tropical agricultural soil

    Agegnehu, Getachew [College of Science, Technology and Engineering, Centre for Tropical Environmental and Sustainability Science, James Cook University, PO Box 6811, Cairns, Queensland 4870 (Australia); Bass, Adrian M. [Hawkesbury Institute for the Environment, University of Western Sydney, Science Road, Richmond, New South Wales 2753 (Australia); Nelson, Paul N.; Bird, Michael I. [College of Science, Technology and Engineering, Centre for Tropical Environmental and Sustainability Science, James Cook University, PO Box 6811, Cairns, Queensland 4870 (Australia)

    2016-02-01

    Soil quality decline represents a significant constraint on the productivity and sustainability of agriculture in the tropics. In this study, the influence of biochar, compost and mixtures of the two on soil fertility, maize yield and greenhouse gas (GHG) emissions was investigated in a tropical Ferralsol. The treatments were: 1) control with business as usual fertilizer (F); 2) 10 t ha{sup −1} biochar (B) + F; 3) 25 t ha{sup −1} compost (Com) + F; 4) 2.5 t ha{sup −1} B + 25 t ha{sup −1} Com mixed on site + F; and 5) 25 t ha{sup −1} co-composted biochar–compost (COMBI) + F. Total aboveground biomass and maize yield were significantly improved relative to the control for all organic amendments, with increases in grain yield between 10 and 29%. Some plant parameters such as leaf chlorophyll were significantly increased by the organic treatments. Significant differences were observed among treatments for the δ{sup 15}N and δ{sup 13}C contents of kernels. Soil physicochemical properties including soil water content (SWC), total soil organic carbon (SOC), total nitrogen (N), available phosphorus (P), nitrate-nitrogen (NO{sub 3}{sup −} N), ammonium-nitrogen (NH{sub 4}{sup +}-N), exchangeable cations and cation exchange capacity (CEC) were significantly increased by the organic amendments. Maize grain yield was correlated positively with total biomass, leaf chlorophyll, foliar N and P content, SOC and SWC. Emissions of CO{sub 2} and N{sub 2}O were higher from the organic-amended soils than from the fertilizer-only control. However, N{sub 2}O emissions generally decreased over time for all treatments and emission from the biochar was lower compared to other treatments. Our study concludes that the biochar and biochar–compost-based soil management approaches can improve SOC, soil nutrient status and SWC, and maize yield and may help mitigate greenhouse gas emissions in certain systems. - Graphical abstract: Grain yield, cation exchange capacity (CEC), soil

  2. Benefits of biochar, compost and biochar–compost for soil quality, maize yield and greenhouse gas emissions in a tropical agricultural soil

    Agegnehu, Getachew; Bass, Adrian M.; Nelson, Paul N.; Bird, Michael I.

    2016-01-01

    Soil quality decline represents a significant constraint on the productivity and sustainability of agriculture in the tropics. In this study, the influence of biochar, compost and mixtures of the two on soil fertility, maize yield and greenhouse gas (GHG) emissions was investigated in a tropical Ferralsol. The treatments were: 1) control with business as usual fertilizer (F); 2) 10 t ha"−"1 biochar (B) + F; 3) 25 t ha"−"1 compost (Com) + F; 4) 2.5 t ha"−"1 B + 25 t ha"−"1 Com mixed on site + F; and 5) 25 t ha"−"1 co-composted biochar–compost (COMBI) + F. Total aboveground biomass and maize yield were significantly improved relative to the control for all organic amendments, with increases in grain yield between 10 and 29%. Some plant parameters such as leaf chlorophyll were significantly increased by the organic treatments. Significant differences were observed among treatments for the δ"1"5N and δ"1"3C contents of kernels. Soil physicochemical properties including soil water content (SWC), total soil organic carbon (SOC), total nitrogen (N), available phosphorus (P), nitrate-nitrogen (NO_3"− N), ammonium-nitrogen (NH_4"+-N), exchangeable cations and cation exchange capacity (CEC) were significantly increased by the organic amendments. Maize grain yield was correlated positively with total biomass, leaf chlorophyll, foliar N and P content, SOC and SWC. Emissions of CO_2 and N_2O were higher from the organic-amended soils than from the fertilizer-only control. However, N_2O emissions generally decreased over time for all treatments and emission from the biochar was lower compared to other treatments. Our study concludes that the biochar and biochar–compost-based soil management approaches can improve SOC, soil nutrient status and SWC, and maize yield and may help mitigate greenhouse gas emissions in certain systems. - Graphical abstract: Grain yield, cation exchange capacity (CEC), soil organic carbon (SOC), soil water content (SWC) and N_2O

  3. The microbial communities and potential greenhouse gas production in boreal acid sulphate, non-acid sulphate, and reedy sulphidic soils

    Šimek, Miloslav, E-mail: misim@upb.cas.cz [Biology Centre AS CR, v. v. i., Institute of Soil Biology, 370 05 České Budějovice (Czech Republic); University of South Bohemia, Faculty of Science, 370 05 České Budějovice (Czech Republic); Virtanen, Seija; Simojoki, Asko [Department of Food and Environmental Sciences, University of Helsinki, FI-00014 Helsinki (Finland); Chroňáková, Alica; Elhottová, Dana; Krištůfek, Václav [Biology Centre AS CR, v. v. i., Institute of Soil Biology, 370 05 České Budějovice (Czech Republic); Yli-Halla, Markku [Department of Food and Environmental Sciences, University of Helsinki, FI-00014 Helsinki (Finland)

    2014-01-01

    Acid sulphate (AS) soils along the Baltic coasts contain significant amounts of organic carbon and nitrogen in their subsoils. The abundance, composition, and activity of microbial communities throughout the AS soil profile were analysed. The data from a drained AS soil were compared with those from a drained non-AS soil and a pristine wetland soil from the same region. Moreover, the potential production of methane, carbon dioxide, and nitrous oxide from the soils was determined under laboratory conditions. Direct microscopic counting, glucose-induced respiration (GIR), whole cell hybridisation, and extended phospholipid fatty acid (PLFA) analysis confirmed the presence of abundant microbial communities in the topsoil and also in the deepest Cg2 horizon of the AS soil. The patterns of microbial counts, biomass and activity in the profile of the AS soil and partly also in the non-AS soil therefore differed from the general tendency of gradual decreases in soil profiles. High respiration in the deepest Cg2 horizon of the AS soil (5.66 μg C g{sup − 1} h{sup − 1}, as compared to 2.71 μg C g{sup − 1} h{sup − 1} in a top Ap horizon) is unusual but reasonable given the large amount of organic carbon in this horizon. Nitrous oxide production peaked in the BCgc horizon of the AS and in the BC horizon of the non-AS soil, but the peak value was ten-fold higher in the AS soil than in the non-AS soil (82.3 vs. 8.6 ng N g{sup − 1}d{sup − 1}). The data suggest that boreal AS soils on the Baltic coast contain high microbial abundance and activity. This, together with the abundant carbon and total and mineral nitrogen in the deep layers of AS soils, may result in substantial gas production. Consequently, high GHG emissions could occur, for example, when the generally high water table is lowered because of arable farming. - Highlights: •Boreal acid sulphate soils contain large amounts of organic C and N in subsoils. •Microbial communities throughout the acid

  4. Leaf Cutter Ant (Atta cephalotes) Soil Modification and In Situ CO2 Gas Dynamics in a Neotropical Wet Forest

    Fernandez Bou, A. S.; Carrasquillo Quintana, O.; Dierick, D.; Harmon, T. C.; Johnson, S.; Schwendenmann, L.; Zelikova, T. J.

    2016-12-01

    The goal of this work is to advance our understanding of soil carbon cycling in highly productive neotropical wet forests. More specifically, we are investigating the influence of leaf cutter ants (LCA) on soil CO2 gas dynamics in primary and secondary forest soils at La Selva Biological Station, Costa Rica. LCA are the dominant herbivore in tropical Americas, responsible for as much as 50% of the total herbivory. Their presence is increasing and their range is expanding because of forest fragmentation and other human impacts. We installed gas sampling wells in LCA (Atta cephalotes) nest and control sites (non-nests in the same soil and forest settings). The experimental design encompassed land cover (primary and secondary forest) and soil type (residual and alluvial). We collected gas samples monthly over an 18-month period. Several of the LCA nests were abandoned during this period. Nevertheless, we continued to sample these sites for LCA legacy effects. In several of the sites, we also installed sensors to continuously monitor soil moisture content, temperature, and CO2 levels. Within the 18-month period we conducted a 2-month field campaign to collect soil and nest vent CO2 efflux data from 3 of the nest-control pairs. Integrating the various data sets, we observed that for most of the sites nest and control soils behaved similarly during the tropical dry season. However, during the wet season gas well CO2 concentrations increased in the control sites while levels in the nests remained at dry season levels. This outcome suggests that ants modify soil gas transport properties (e.g., tortuosity). In situ time series and efflux sampling campaign data corroborated these findings. Abandoned nest CO2 levels were similar to those of the active nests, supporting the notion of a legacy effect from LCA manipulations. For this work, the period of abandonment was relatively short (several months to 1 year maximum), which appears to be insufficient for estimating the

  5. A survey of caesium-137 and plutonium in British soils in 1977

    Cawsw, P.A.; Horrill, A.D.

    1986-02-01

    Measurements have been made of the accumulation to 30 cm depth of Cs-137 and plutonium in soils from permanent grassland and woodland in England, Scotland and Wales, and of the concentrations in grass. In Scotland, peat has also been sampled. The sampling points were carefully selected with due regard to their soil type and future permanence, to establish a network of grassland sites at which radionuclide concentrations may be measured over the long-term. The main objective of the survey is to provide information on the integrated deposition of Cs-137, Pu-239+240 and Pu-238 from the atmosphere to provide a baseline in 1977 with which to assess the significance of radioactive accumulations from the routine operation of nuclear facilities. Further objectives are to study the transfer of radionuclides to vegetation, and to compare the concentrations with generalised derived limits for radiological assessment. (author)

  6. Land cover changes and greenhouse gas emissions in two different soil covers in the Brazilian Caatinga.

    Ribeiro, Kelly; Sousa-Neto, Eráclito Rodrigues de; Carvalho, João Andrade de; Sousa Lima, José Romualdo de; Menezes, Rômulo Simões Cezar; Duarte-Neto, Paulo José; da Silva Guerra, Glauce; Ometto, Jean Pierre Henry Baulbaud

    2016-11-15

    The Caatinga biome covers an area of 844,453km(2) and has enormous endemic biodiversity, with unique characteristics that make it an exclusive Brazilian biome. It falls within the earth's tropical zone and is one of the several important ecoregions of Brazil. This biome undergoes natural lengthy periods of drought that cause losses in crop and livestock productivity, having a severe impact on the population. Due to the vulnerability of this ecosystem to climate change, livestock has emerged as the main livelihood of the rural population, being the precursor of the replacement of native vegetation by grazing areas. This study aimed to measure GHG emissions from two different soil covers: native forest (Caatinga) and pasture in the municipality of São João, Pernambuco State, in the years 2013 and 2014. GHG measurements were taken by using static chamber techniques in both soil covers. According to a previous search, so far, this is the first study measuring GHG emissions using the static chamber in the Caatinga biome. N2O emissions ranged from -1.0 to 4.2mgm(-2)d(-1) and -1.22 to 3.4mgm(-2)d(-1) in the pasture and Caatinga, respectively, and they did not significantly differ from each other. Emissions were significantly higher during dry seasons. Carbon dioxide ranged from -1.1 to 14.1 and 1.2 to 15.8gm(-2)d(-1) in the pasture and Caatinga, respectively. CO2 emissions were higher in the Caatinga in 2013, and they were significantly influenced by soil temperature, showing an inverse relation. Methane emission ranged from 6.6 to 6.8 and -6.0 to 4.8mgm(-2)d(-1) in the pasture and Caatinga, respectively, and was significantly higher only in the Caatinga in the rainy season of 2014. Soil gas fluxes seemed to be influenced by climatic and edaphic conditions as well as by soil cover in the Caatinga biome. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Causes of poor sealant performance in soil-gas-resistant foundations

    Scott, A.

    1994-01-01

    Sealants for radon-resistant foundation construction must seal the gap between concrete sections. Modern sealants have such low permeability that seal performance depends only on the permeability of the material that contacts the sealant. The surface permeability of concrete walls and floors was measured by a specially designed permeameter, which measures the airflow induced by a pressure difference across a temporary test seal applied to the surface. The permeability of bulk concrete is about 10 -15 m 2 . Areas free of surface defects had surface permeability ranging from 10 -14 to 10 -16 m 2 . However, surface defects are common on concrete wall surfaces, which increase the permeability to >10 -12 m 2 , too high for standard seal designs to be adequate as the only method of soil gas and radon exclusion. Radon-resistant seals require either extended contact widths or mechanical removal of the surface layer and defects. (au) (4 refs.)

  8. Effect of reed canary grass cultivation on greenhouse gas emission from peat soil at controlled rewetting

    Karki, Sandhya; Elsgaard, Lars; Lærke, Poul Erik

    2015-01-01

    Cultivation of bioenergy crops in rewetted peatland (paludiculture) is considered as a possible land use option to mitigate greenhouse gas (GHG) emissions. However, bioenergy crops like reed canary grass (RCG) can have a complex influence on GHG fluxes. Here we determined the effect of RCG...... and bare soil were measured at weekly to fortnightly intervals with static chamber techniques for a period of 1 year. Cultivation of RCG increased both ER and CH4 emissions, but decreased the N2O emissions. The presence of RCG gave rise to 69, 75 and 85% of total ER at −20, −10 and 0 cm GWL, respectively...... from ER were obviously the dominant RCG-derived GHG flux, but above-ground biomass yields, and preliminary measurements of gross photosynthetic production, showed that ER could be more than balanced due to the photosynthetic uptake of CO2 by RCG. Our results support that RCG cultivation could be a good...

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

    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

  10. Use of dilute ammonia gas for treatment of 1,2,3-trichloropropane and explosives-contaminated soils.

    Coyle, Charles G; Waisner, Scott A; Medina, Victor F; Griggs, Chris S

    2017-12-15

    Laboratory studies were performed to test a novel reactive gas process for in-situ treatment of soils containing halogenated propanes or explosives. A soil column study, using a 5% ammonia-in-air mixture, established that the treatment process can increase soil pH from 7.5 to 10.2. Batch reactor experiments were performed to demonstrate contaminant destruction in sealed jars exposed to ammonia. Comparison of results from batch reactors that were, and were not, exposed to ammonia demonstrated reductions in concentrations of 1,2,3-trichloropropane (TCP), 1,3-dichloropropane (1,3-DCP), 1,2-dicholoropropane (1,2-DCP) and dibromochloropropane (DBCP) that ranged from 34 to 94%. Decreases in TCP concentrations at 23° C ranged from 37 to 65%, versus 89-94% at 62° C. A spiked soil column study was also performed using the same set of contaminants. The study showed a pH penetration distance of 30 cm in a 2.5 cm diameter soil column (with a pH increase from 8 to > 10), due to treatment via 5% ammonia gas at 1 standard cubic centimeter per minute (sccm) for 7 days. Batch reactor tests using explosives contaminated soils exhibited a 97% decrease in 2,4,6-trinitrotoluene (TNT), an 83% decrease in nitrobenzene, and a 6% decrease in hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). A biotransformation study was also performed to investigate whether growth of ammonia-oxidizing microorganisms could be stimulated via prolonged exposure of soil to ammonia. Over the course of the 283 day study, only a very small amount of nitrite generation was observed; indicating very limited ammonia monooxygenase activity. Overall, the data indicate that ammonia gas addition can be a viable approach for treating halogenated propanes and some types of explosives in soils. Published by Elsevier Ltd.

  11. A survey of radioactive caesium in soils of Cumbria and North Lancashire

    Baker, S.J.; Cawse, P.A.

    1990-09-01

    A network of soil sampling sites covering an area of some 2500km 2 in Cumbria was sampled by Harwell Laboratory in 1978. The spatial distribution of sampling points was based on a grid of 10km side, thus providing 30 sites under permanent grassland. In 1979, the grid was extended northwards to Carlisle and in a southerly direction to Fleetwood, Lancashire, giving a further 24 sites. This provided a reference baseline of background radioactivity, mainly arising from the accumulated atmospheric deposition of fallout from nuclear weapons tests over some 30 years, and also determined the distribution of emissions from the nuclear establishment at Sellafield that is superimposed upon the natural background of radioactivity in soil. The grid survey has now been repeated in 1988/89 to record increases in radioactive caesium caused by fallout from the accident at Chernobyl, USSR, in April 1986. The accumulated depositions of 137 Cs recorded to 30cm soil depth in 1988/89 were in the range 2.0 (at Bowness on Solway) to 28kBq/m 2 (at Eskmeals). A comparison of results obtained pre-Chernobyl (in 1978) with post-Chernobyl values assessed ten years later shows increases of 137 Cs accumulations at 18 of the surveys sites, 1.5 to 2-fold at 20 sites, 2 to 4 fold at 13 sites and 4 to 7 fold at St Bees, Harrington and Little Annaside (near Bootle, Cumbria). Ratios of Cs-137/Cs-134 at 0-15cm depth of soil were in the range 3.0 - 26.4 in 1988/89, compared with a ratio of ∼ 3.0 in Chernobyl fallout when decay-corrected. Lowest ratios occurred in west Cumbria which showed the highest accumulations of Cs-137 between 290-330km easting and 480-530km northing. The retention of Cs-137 by the top 15cm of soil in 1988/89 relative to the accumulation to 30cm depth averaged 87% compared with 78% in the pre-Chernobyl survey made in 1978/79, and is attributed to surface accumulation of debris from the accident. (author)

  12. Assessing the probability of carbon and greenhouse gas benefit from the management of peat soils

    Worrall, F.; Bell, M.J.; Bhogal, A.

    2010-01-01

    This study proposes a method for assessing the probability that land management interventions will lead to an improvement in the carbon sink represented by peat soils. The method is able to: combine studies of different carbon uptake and release pathways in order to assess changes on the overall carbon or greenhouse gas budget; calculate the probability of the management or restoration leading to an improvement in the budget; calculate the uncertainty in that probability estimate; estimate the equivalent number of complete budgets available from the combination of the literature; test the difference in the outcome of different land management interventions; and provide a method for updating the predicted probabilities as new studies become available. Using this methodology, this study considered the impact of: afforestation, managed burning, drainage, drain-blocking, grazing removal; and revegetation, on the carbon budget of peat soils in the UK. The study showed that afforestation, drain-blocking, revegetation, grazing removal and cessation of managed burning would bring a carbon benefit, whereas deforestation, managed burning and drainage would bring a disbenefit. The predicted probabilities of a benefit are often equivocal as each management type or restoration often leads to increase in uptake in one pathway while increasing losses in another.

  13. [Effects of soil water status on gas exchange of peanut and early rice leaves].

    Chen, Jiazhou; Lü, Guoan; He, Yuanqiu

    2005-01-01

    The gas exchange characteristics of peanut and early rice leaves were investigated in experimental plots under different soil water conditions over a long growth period. The results showed that at the branching stage of peanut, the stomatal conductance (Gs) and transpiration rate (Tr) decreased slightly under mild and moderate soil water stress, while the net photosynthetic rate (Pn) and leaf water use efficiency (WUE) increased. The Gs/Tr ratio also increased under mild water stress, but decreased under moderate water stress. At podding stage, the Gs, Tr, Gs/Tr ratio and Pn decreased, while WUE increased significantly under mild and moderate water stress. The peanut was suffered from water stress at its pod setting stage. At the grain filling stage of early rice, the Gs, Tr and Gs/Tr ratio fluctuated insignificantly under mild and moderate water stress, while Pn and WUE increased significantly, with an increase in grain yield under mild water stress. It's suggested that the combination of Gs and Gs/Tr ratio could be a reference index for crop water stress, namely, crops could be hazarded by water stress when Gs and Gs/Tr decreased synchronously.

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

    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

  15. Volatile Gas Production by Methyl Halide Transferase: An In Situ Reporter Of Microbial Gene Expression In Soil.

    Cheng, Hsiao-Ying; Masiello, Caroline A; Bennett, George N; Silberg, Jonathan J

    2016-08-16

    Traditional visual reporters of gene expression have only very limited use in soils because their outputs are challenging to detect through the soil matrix. This severely restricts our ability to study time-dependent microbial gene expression in one of the Earth's largest, most complex habitats. Here we describe an approach to report on dynamic gene expression within a microbial population in a soil under natural water levels (at and below water holding capacity) via production of methyl halides using a methyl halide transferase. As a proof-of-concept application, we couple the expression of this gas reporter to the conjugative transfer of a bacterial plasmid in a soil matrix and show that gas released from the matrix displays a strong correlation with the number of transconjugant bacteria that formed. Gas reporting of gene expression will make possible dynamic studies of natural and engineered microbes within many hard-to-image environmental matrices (soils, sediments, sludge, and biomass) at sample scales exceeding those used for traditional visual reporting.

  16. Post-Chernobyl surveys of radiocaesium in soil, vegetation, wildlife and fungi in Great Britain

    Chaplow, J.S.; Beresford, N.A.; Barnett, C.L. [Lancaster Environment Centre, Lancaster (United Kingdom). Centre for Ecology and Hydrology,

    2015-07-01

    The data set ''Post Chernobyl surveys of radiocaesium in soil, vegetation, wildlife and fungi in Great Britain'' was developed to enable data collected by the Natural Environment Research Council after the Chernobyl accident to be made publicly available. Data for samples collected between May 1986 (immediately after Chernobyl) to spring 1997 are presented. Additional data to radiocaesium concentrations are presented where available. The data have value in trying to assess the contribution of new sources of radiocaesium in the environment, providing baseline data for future planned releases and to aid the development and testing of models.

  17. Impact of Leaching Conditions on Constituents Release from Flue Gas Desulfurization Gypsum (FGDG) and FGDG-Soil Mixture

    The interest in using Flue Gas Desulfurization Gypsum(FGDG) has increased recently. This study evaluates the leaching characteristics of trace elements in "modern" FGDG (produced after fly ash removal) and FGDG-mixed soil (SF) under different environmental conditions using rece...

  18. EMISSION OF SOIL GAS RADON CONCENTRATION AROUND MAIN CENTRAL THRUST IN UKHIMATH (RUDRAPRAYAG) REGION OF GARHWAL HIMALAYA.

    Aswal, Sunita; Kandari, Tushar; Sahoo, B K; Bourai, A A; Ramola, R C

    2016-10-01

    In this paper, the result of systematic measurement of the soil gas radon concentrations is discussed and the background values are defined along and around the Main Central Thrust (MCT) in Ukhimath region of Garhwal Himalaya, India. The Ukhimath region is being subjected to intense neotectonic activities like earthquake and landslide. For the systematic study, the measurement has been done in grid pattern form along and across the MCT. The soil gas radon concentrations were measured using RAD7 with appropriate accessories and followed proper protocol proposed by the manufacturer. The soil gas concentration was measured at different depths 10, 30 and 50 cm with a wide range of different points from the MCT. At 10 cm depth, the soil gas radon concentration was found to vary from 125 to 800 Bq m -3 with an average of 433 Bq m -3 ; at 30 cm, it was found to vary from 203 to 32 500 Bq m -3 with an average of 2387 Bq m -3 ; and at 50 cm, it was found to vary from 1330 to 46 000 Bq m -3 with an average of 15 357 Bq m -3 The data analysis clearly reveals anomalous values along the fault. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. Emission of soil gas radon concentration around main central thrust in Ukhimath (Rudraprayag) region of Garhwal Himalaya

    Aswal, Sunita; Kandari, Tushar; Bourai, A.A.; Ramola, R.C.; Sahoo, B.K.

    2016-01-01

    In this paper, the result of systematic measurement of the soil gas radon concentrations is discussed and the background values are defined along and around the Main Central Thrust (MCT) in Ukhimath region of Garhwal Himalaya, India. The Ukhimath region is being subjected to intense neotectonic activities like earthquake and landslide. For the systematic study, the measurement has been done in grid pattern form along and across the MCT. The soil gas radon concentrations were measured using RAD7 with appropriate accessories and followed proper protocol proposed by the manufacturer. The soil gas concentration was measured at different depths 10, 30 and 50 cm with a wide range of different points from the MCT. At 10 cm depth, the soil gas radon concentration was found to vary from 125 to 800 Bq m -3 with an average of 433 Bq m -3 ; at 30 cm, it was found to vary from 203 to 32 500 Bq m -3 with an average of 2387 Bq m -3 ; and at 50 cm, it was found to vary from 1330 to 46 000 Bq m -3 with an average of 15 357 Bq m -3 . The data analysis clearly reveals anomalous values along the fault. (authors)

  20. Pyrolysis-gas chromatography/mass spectrometry of soil organic matter extracted from a Brazilian mangrove and Spanish salt marshes

    Perobelli Ferreira, F.; Buurman, P.; Macias, F.; Otero, X.L.; Boluda, R.

    2009-01-01

    The soil organic matter (SOM) extracted under different vegetation types from a Brazilian mangrove (Pai Matos Island, São Paulo State) and from three Spanish salt marshes (Betanzos Ría and Corrubedo Natural Parks, Galícia, and the Albufera Natural Park, Valencia) was investigated by pyrolysis-gas

  1. Mapping of gas radon in soil of the Fresnillo City, Zacatecas; Mapeo de gas radon en suelo de la Ciudad de Fresnillo, Zacatecas

    Gomez Q, I. S.; Lopez del R, H.; Davila R, J. I.; Mireles G, F., E-mail: hlopezdelrio@hotmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2012-10-15

    With the purpose of locating areas with high rates of gas radon exhalation, it has begun to measure the radon flow in soil for residence use in the Fresnillo City, Zacatecas State, Mexico, applying the method of the open vial and liquid scintillation. The gas radon accumulation is made in a camera situated to a depth between 25 and 35 cm. In this work the partial results of the research in course are presented. The values obtained for the radon exhalation have varied of <2.25 up to 14.42 Bq/m{sup 2}{center_dot}h. (Author)

  2. Description of gas hydrates equilibria in sediments using experimental data of soil water potential

    Istomin, V. [NOVATEK, Moscow (Russian Federation); Chuvilin, E. [Moscow State Univ., Moscow (Russian Federation). Dept. of Geology; Makhonina, N.; Kvon, V. [VNIIGAZ, Moscow (Russian Federation); Safonov, S. [Schlumberger Moscow Research, Moscow (Russian Federation)

    2008-07-01

    Analytical relationships have been developed between hydrate dissociation pressure and vapor pressure above the pore water surface. In addition, experiments have been discussed in numerous publications on the effect of narrow interconnected throats between pores on clathrate dissociation conditions in porous media. This paper presented an approach that improved upon the available thermodynamic methods for calculation of hydrate phase equilibria. The approach took into account the properties of pore water in natural sediments including three-phase equilibrium of gas-pore water-gas hydrate in a similar way as for unfrozen water in geocryology science. The purpose of the paper was to apply and adapt geocryology and soil physics method to the thermodynamic calculation of non-clathrated water content in sediments. It answered the question of how to estimate the non-clathrated water content if pore water potential was known. The paper explained the thermodynamics of water phase in porous media including the thermodynamic properties of supercooled water, the thermodynamic properties of pore water and pore ice in sediments, and the phase equilibria of pore water. The paper also discussed the quantitative techniques that were utilized for determination of unfrozen water content in sediments and its dependence on temperature variation. These included contact-saturation, calorimetric, dielectric, nuclear magnetic resonance, and others. The thermodynamic calculations of pore water phase equilibria were also presented. 30 refs., 5 tabs., 8 figs.

  3. Large-scale sulfolane-impacted soil remediation at a gas plant

    Lavoie, G.; Rockwell, K. [Biogenie Inc., Calgary, AB (Canada)

    2006-07-01

    A large-scale sulfolane-impacted soil remediation project at a gas plant in central Alberta was discussed. The plant was operational from the 1960s to present and the former operation involved the Sulfinol process which resulted in groundwater contamination. In 2005, the client wanted to address the sources area. The Sulfinol process has been used since the 1960s to remove hydrogen sulfide and other corrosive gases from natural gas streams. Sulfinol uses sulfolane and diisopropanolamine. Sulfolane is toxic, non-volatile, and water soluble. The presentation also addressed the remediation objectives and an additional site assessment that was conducted to better delineate the sulfolane and sulphur plume, as well as metals. The findings of the ESA and site specific challenges were presented. These challenges included: plant operation concerns; numerous overhead, surface, and underground structures; large volume of impacted material, limited space available on site; several types of contaminants; and time required to perform the overall work. Next, the sulfolane remediation strategy was discussed including advantages and results of the investigation. Last, the results of the project were presented. It was found that there were no recordable safety incidents and that all remedial objectives were achieved. tabs., figs.

  4. Changes in liquid water alter nutrient bioavailability and gas diffusion in frozen antarctic soils contaminated with petroleum hydrocarbons.

    Harvey, Alexis Nadine; Snape, Ian; Siciliano, Steven Douglas

    2012-02-01

    Bioremediation has been used to remediate petroleum hydrocarbon (PHC)-contaminated sites in polar regions; however, limited knowledge exists in understanding how frozen conditions influence factors that regulate microbial activity. We hypothesized that increased liquid water (θ(liquid) ) would affect nutrient supply rates (NSR) and gas diffusion under frozen conditions. If true, management practices that increase θ(liquid) should also increase bioremediation in polar soils by reducing nutrient and oxygen limitations. Influence of θ(liquid) on NSR was determined using diesel-contaminated soil (0-8,000 mg kg(-1)) from Casey Station, Antarctica. The θ(liquid) was altered between 0.007 and 0.035 cm(3) cm(-3) by packing soil cores at different bulk densities. The nutrient supply rate of NH 4+ and NO 3-, as well as gas diffusion coefficient, D(s), were measured at two temperatures, 21°C and -5°C, to correct for bulk density effects. Freezing decreased NSR of both NH 4+ and NO 3-, with θ(liquid) linked to nitrate and ammonia NSR in frozen soil. Similarly for D(s), decreases due to freezing were much more pronounced in soils with low θ(liquid) compared to soils with higher θ(liquid) contents. Additional studies are needed to determine the relationship between degradation rates and θ(liquid) under frozen conditions. Copyright © 2011 SETAC.

  5. 1997 survey of residential direct sales of natural gas in Canada

    Bacalso, N.; Given, G.

    1997-01-01

    This report comments on the prevailing state of direct sales of natural gas in Canada and shows how the situation has changed since the Canadian Energy Research Institute initiated its first survey in 1994. The report describes current regulations relating to direct sales and quantifies direct sales activity in each of the provinces. Information on direct sales volumes and the number of direct sales customers contained in the report was gathered through interviews with local distribution companies, provincial regulatory commissions and many natural gas brokers and marketers. It was noted that Ontario and Quebec (where the industry is self-regulating) were the two provinces with the highest volumes of residential direct sales. The need for regular monitoring was recommended in view of the current climate of rapid changes in the energy market. 7 tabs., 1 fig

  6. Technology survey for real-time monitoring of plutonium in a vitrifier off-gas system

    Berg, J.M.; Veirs, D.K.

    1996-01-01

    We surveyed several promising measurement technologies for the real-time monitoring of plutonium in a vitrifier off-gas system. The vitrifier is being developed by Westinghouse Savannah River Corp. and will be used to demonstrate vitrification of plutonium dissolved in nitric acid for fissile material disposition. The risk of developing a criticality hazard in the off-gas processing equipment can be managed by using available measurement technologies. We identified several potential technologies and methods for detecting plutonium that are sensitive enough to detect the accumulation of a mass sufficient to form a criticality hazard. We recommend gross alpha-monitoring technologies as the most promising option for Westinghouse Savannah River Corp. to consider because that option appears to require the least additional development. We also recommend further consideration for several other technologies because they offer specific advantages and because gross alpha-monitoring could prove unsuitable when tested for this specific application

  7. A national survey of the prevalence of schistosomiasis and soil transmitted helminths in Malaŵi

    Shaba Bina

    2004-11-01

    Full Text Available Abstract Background Past estimates have put the prevalence of schistosomiasis between 40% and 50% in the Malawi population overall based on studies undertaken ten years or more ago. More recent surveys in known high risk areas find similar levels. However control measures, changing ecology and migration may have led to changes in the prevalence of schistosomiasis in different parts of Malawi. A national schistosomiasis and soil-transmitted helminth (STH survey was undertaken to measure the distribution, prevalence and intensity of infection in November 2002. Methods A school was selected randomly from a random sample of 30 Traditional Authorities stratified by six distinct ecological zones, and 1,664 year 3 pupils (9–10 year olds were questioned about recent illnesses and "red urine". Samples of urine and faeces were examined for the presence of eggs using the standard Kato-Katz technique for soil-transmitted helminths and intestinal schistosomiasis and urine samples using the filtration technique for Schistosoma haematobium. Results The prevalence of Schistosoma mansoni is 0.4% (95% CI 0–1.3%, S. haematobium 6.9% (95% CI 1.9 – 11.9%, hookworm 1.3% (95% CI 0.4–2.3%, Ascariasis 0.5% (95% CI 0.1–1.0% and trichuriasis 0% in year 3 pupils (modal age 10 years of age. Intensity of infection is low for all infections except for 2.5% who have high intensity S. haematobium infection. The "red urine" question is 67% sensitive and 80% specific for positive S. haematobium microscopy. Conclusions The reduction in prevalences may be real as a result of recent control measures, or false if historical results were based on surveys of high risk populations. Another explanation is that this survey used an unrepresentative sample of schools. Detailed analysis suggests this is unlikely. Recommendations include the use of a 30% positive threshold for the "red urine" screening question to be used in schoolchildren in high prevalence areas. This survey

  8. Using 13C-labeled benzene and Raman gas spectroscopy to investigate respiration and biodegradation kinetics following soil contamination

    Jochum, Tobias; Popp, Juergen; Frosch, Torsten

    2016-04-01

    Soil and groundwater contamination with benzene can cause serious environmental damages. However, many soil microorganisms are capable to adapt and known to strongly control the fate of organic contamination. Cavity enhanced Raman gas spectroscopy (CERS) was applied to investigate the short-term response of indigenous soil bacteria to a sudden surface contamination with benzene regarding the temporal variations of gas products and their exchange rates with the adjacent atmosphere. 13C-labeled benzene was spiked on a silty-loamy soil column (sampled from Hainich National Park, Germany) in order to track and separate the changes in heterotrophic soil respiration - involving 12CO2 and O2 - from the microbial process of benzene degradation, which ultimately forms 13CO2.1 The respiratory quotient (RQ) of 0.98 decreased significantly after the spiking and increased again within 33 hours to a value of 0.72. This coincided with maximum 13CO2 concentration rates (0.63 μ mol m-2 s-1), indicating highest benzene degradation at 33 hours after the spiking event. The diffusion of benzene in the headspace and the biodegradation into 13CO2 were simultaneously monitored and 12 days after the benzene spiking no measurable degradation was detected anymore.1 The RQ finally returned to a value of 0.96 demonstrating the reestablished aerobic respiration. In summary, this study shows the potential of combining Raman gas spectroscopy and stable isotopes to follow soil microbial biodegradation dynamics while simultaneously monitoring the underlying respiration behavior. Support by the Collaborative Research Center 1076 Aqua Diva is kindly acknowledged. We thank Beate Michalzik for soil analysis and discussion. 1. T. Jochum, B. Michalzik, A. Bachmann, J. Popp and T. Frosch, Analyst, 2015, 140, 3143-3149.

  9. Compressed Natural Gas (CNG) Transit Bus Experience Survey: April 2009--April 2010

    Adams, R.; Horne, D. B.

    2010-09-01

    This survey was commissioned by the U.S. Department of Energy (DOE) and the National Renewable Energy Laboratory (NREL) to collect and analyze experiential data and information from a cross-section of U.S. transit agencies with varying degrees of compressed natural gas (CNG) bus and station experience. This information will be used to assist DOE and NREL in determining areas of success and areas where further technical or other assistance might be required, and to assist them in focusing on areas judged by the CNG transit community as priority items.

  10. Combining 137Cs and topographic surveys for measuring soil erosion/deposition patterns in a rapidly accreting area

    Ritchie, J.C.

    2000-01-01

    Narrow, stiff grass hedges are biological barriers designed to slow runoff and capture soils carried in runoff water. This study was designed to measure quantitatively the deposition of soil up slope of a narrow, stiff grass hedge using topographic and 137 Cs surveys. Topographic surveys made in 1991, 1995, and 1998 measured 1 to 2 cm yr -1 of recent sediment deposited up slope of the grass hedge. 137 Cs analyses of soil samples were used to determine the medium-term (45 years) soil redistribution patterns. Erosion rates and patterns determined using 137 Cs measured medium-term erosion near the hedge do not reflect the recent deposition patterns near the grass hedge measured by topographic surveys. Using the combination of topographic and 137 Cs surveys allows a better understanding of the role of grass hedges as barriers for capturing eroding soils and suggest that the recent deposition is associated with the grass hedge but that there is still a net loss of soil near the hedge position over the past 45 years. (author)

  11. Soils

    Emily Moghaddas; Ken Hubbert

    2014-01-01

    When managing for resilient forests, each soil’s inherent capacity to resist and recover from changes in soil function should be evaluated relative to the anticipated extent and duration of soil disturbance. Application of several key principles will help ensure healthy, resilient soils: (1) minimize physical disturbance using guidelines tailored to specific soil types...

  12. Modeling and forecasting the supply of oil and gas: a survey of existing approaches

    Walls, M.A.

    1992-01-01

    This paper surveys the literature on empirical oil and gas supply modeling. The models fall into two broad categories: geologic/engineering and econometric. Two types of geologic/engineering models are surveyed - play analysis, or simulation models and discovery process models. A third category of supply models, 'hybrids', which contain features of both econometric and discovery process models are also discussed. Particular attention is paid to whether or not the models have linkages between a dynamic model of producer optimizing behaviour and the factors governing supply of the resource; whether or not expectations of future prices, costs, and other stochastic variables are incorporated; whether the physical characteristics of non-renewable resources are captured; and how well the models perform. The paper concludes that the best path for future research efforts is a hybrid approach where the econometric component is derived from a stochastic dynamic optimization model of exploration behaviour. 51 refs., 3 figs., 1 tab

  13. Soil radium, soil gas radon and indoor radon empirical relationships to assist in post-closure impact assessment related to near-surface radioactive waste disposal.

    Appleton, J D; Cave, M R; Miles, J C H; Sumerling, T J

    2011-03-01

    Least squares (LS), Theil's (TS) and weighted total least squares (WTLS) regression analysis methods are used to develop empirical relationships between radium in the ground, radon in soil and radon in dwellings to assist in the post-closure assessment of indoor radon related to near-surface radioactive waste disposal at the Low Level Waste Repository in England. The data sets used are (i) estimated ²²⁶Ra in the < 2 mm fraction of topsoils (eRa226) derived from equivalent uranium (eU) from airborne gamma spectrometry data, (ii) eRa226 derived from measurements of uranium in soil geochemical samples, (iii) soil gas radon and (iv) indoor radon data. For models comparing indoor radon and (i) eRa226 derived from airborne eU data and (ii) soil gas radon data, some of the geological groupings have significant slopes. For these groupings there is reasonable agreement in slope and intercept between the three regression analysis methods (LS, TS and WTLS). Relationships between radon in dwellings and radium in the ground or radon in soil differ depending on the characteristics of the underlying geological units, with more permeable units having steeper slopes and higher indoor radon concentrations for a given radium or soil gas radon concentration in the ground. The regression models comparing indoor radon with soil gas radon have intercepts close to 5 Bq m⁻³ whilst the intercepts for those comparing indoor radon with eRa226 from airborne eU vary from about 20 Bq m⁻³ for a moderately permeable geological unit to about 40 Bq m⁻³ for highly permeable limestone, implying unrealistically high contributions to indoor radon from sources other than the ground. An intercept value of 5 Bq m⁻³ is assumed as an appropriate mean value for the UK for sources of indoor radon other than radon from the ground, based on examination of UK data. Comparison with published data used to derive an average indoor radon: soil ²²⁶Ra ratio shows that whereas the published data are

  14. Radon survey and soil gamma doses in primary schools of Batman, Turkey.

    Damla, Nevzat; Aldemir, Kamuran

    2014-06-01

    A survey was conducted to evaluate levels of indoor radon and gamma doses in 42 primary schools located in Batman, southeastern Anatolia, Turkey. Indoor radon measurements were carried out using CR-39 solid-state nuclear track detector-based radon dosimeters. The overall mean annual (222)Rn activity in the surveyed area was found to be 49 Bq m(-3) (equivalent to an annual effective dose of 0.25 mSv). However, in one of the districts (Besiri) the maximum radon value turned out to be 307 Bq m(-3). The estimated annual effective doses are less than the recommended action level (3-10 mSv). It is found that the radon concentration decreases with increasing floor number. The concentrations of natural and artificial radioisotopes were determined using gamma-ray spectroscopy for soil samples collected in close vicinity of the studied schools. The mean gamma activity concentrations in the soil samples were 31, 25, 329 and 12 Bq kg(-1) for (226)Ra, (232)Th, (40)K and (137)Cs, respectively. The radiological parameters such as the absorbed dose rate in air and the annual effective dose equivalent were calculated. These radiological parameters were evaluated and compared with the internationally recommended values.

  15. Fiscal 2000 survey report. Feasibility study of reciprocative transportation system for carbon dioxide and natural gas utilizing gas hydrate; 2000 nendo gas hidrate wo riyosuru nisanka tanso to tennen gas no kogo yuso system no kanosei chosa hokokusho

    NONE

    2001-03-01

    A reciprocative CO2/CH{sub 4} transportation system will constitute a foundation on which minor gas fields may be made good use of in the Asia-Pacific region. For the construction of such a system, a survey is conducted into key technologies of separating CO2 from combustion exhaust with the aid of the hydrate process, reciprocative CO2/CH{sub 4} transportation with hydrate acting as medium, and subsurface CO2 storage and its utilization in minor gas fields or the like. The contents of the survey and the results fall in six areas, which are (1) the states of greenhouse gas reduction and natural gas utilization, (2) reciprocative CO2/CH{sub 4} transportation with hydrate acing as medium, (3) CO2 separation from combustion exhaust with the aid of the hydrate process, (4) reciprocative CO2/CH{sub 4} transportation with hydrate acing as medium, (5) subsurface CO2 storage and its utilization in minor gas fields, and (6) the establishment of a reciprocative CO2/CH{sub 4} transportation system and the evaluation of its cost performance. (NEDO)

  16. Impacts of prescribed burning on soil greenhouse gas fluxes in a suburban native forest of south-eastern Queensland, Australia

    Zhao, Y.; Wang, Y. Z.; Xu, Z. H.; Fu, L.

    2015-11-01

    Prescribed burning is a forest management practice that is widely used in Australia to reduce the risk of damaging wildfires. Prescribed burning can affect both carbon (C) and nitrogen (N) cycling in the forest and thereby influence the soil-atmosphere exchange of major greenhouse gases, i.e. carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). To quantify the impact of a prescribed burning (conducted on 27 May 2014) on greenhouse gas exchange and the potential controlling mechanisms, we carried out a series of field measurements before (August 2013) and after (August 2014 and November 2014) the fire. Gas exchange rates were determined in four replicate plots which were burned during the combustion and in another four adjacent unburned plots located in green islands, using a set of static chambers. Surface soil properties including temperature, pH, moisture, soil C and N pools were also determined either by in situ measurement or by analysing surface 10 cm soil samples. All of the chamber measurements indicated a net sink of atmospheric CH4, with mean CH4 uptake ranging from 1.15 to 1.99 mg m-2 d-1. Prescribed burning significantly enhanced CH4 uptake as indicated by the significant higher CH4 uptake rates in the burned plots measured in August 2014. In the following 3 months, the CH4 uptake rate was recovered to the pre-burning level. Mean CO2 emission from the forest soils ranged from 2721.76 to 7113.49 mg m-2 d-1. The effect of prescribed burning on CO2 emission was limited within the first 3 months, as no significant difference was observed between the burned and the adjacent unburned plots in both August and November 2014. The CO2 emissions showed more seasonal variations, rather than the effects of prescribed burning. The N2O emission in the plots was quite low, and no significant impact of prescribed burning was observed. The changes in understory plants and litter layers, surface soil temperature, C and N substrate availability and microbial

  17. Analysis of phthalate esters in soils near an electronics manufacturing facility and from a non-industrialized area by gas purge microsyringe extraction and gas chromatography

    Wu, Wei [MOE Key Laboratory of Environment and Health, Institute of Environmental Medicine, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei (China); Hu, Jia [Suzhou Center for Disease Prevention and Control, Suzhou, Jiangsu (China); Wang, Jinqi; Chen, Xuerong; Yao, Na [MOE Key Laboratory of Environment and Health, Institute of Environmental Medicine, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei (China); Tao, Jing, E-mail: jingtao1982@126.com [MOE Key Laboratory of Environment and Health, Institute of Environmental Medicine, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei (China); Zhou, Yi-Kai, E-mail: zhouyk@mails.tjmu.edu.cn [MOE Key Laboratory of Environment and Health, Institute of Environmental Medicine, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei (China)

    2015-03-01

    Here, a novel technique is described for the extraction and quantitative determination of six phthalate esters (PAEs) from soils by gas purge microsyringe extraction and gas chromatography. Recovery of PAEs ranged from 81.4% to 120.3%, and the relative standard deviation (n = 6) ranged from 5.3% to 10.5%. Soil samples were collected from roadsides, farmlands, residential areas, and non-cultivated areas in a non-industrialized region, and from the same land-use types within 1 km of an electronics manufacturing facility (n = 142). Total PAEs varied from 2.21 to 157.62 mg kg{sup −1} in non-industrialized areas and from 8.63 to 171.64 mg kg{sup −1} in the electronics manufacturing area. PAE concentrations in the non-industrialized area were highest in farmland, followed (in decreasing order) by roadsides, residential areas, and non-cultivated soil. In the electronics manufacturing area, PAE concentrations were highest in roadside soils, followed by residential areas, farmland, and non-cultivated soils. Concentrations of dimethyl phthalate (DMP), diethyl phthalate (DEP), and di-n-butyl phthalate (DnBP) differed significantly (P < 0.01) between the industrial and non-industrialized areas. Principal component analysis indicated that the strongest explanatory factor was related to DMP and DnBP in non-industrialized soils and to butyl benzyl phthalate (BBP) and DMP in soils near the electronics manufacturing facility. Congener-specific analysis confirmed that diethylhexyl phthalate (DEHP) was a predictive indication both in the non-industrialized area (r{sup 2} = 0.944, P < 0.01) and the industrialized area (r{sup 2} = 0.860, P < 0.01). The higher PAE contents in soils near the electronics manufacturing facility are of concern, considering the large quantities of electronic wastes generated with ongoing industrialization. - Highlights: • A new method for determining phthalate esters in soil samples was developed. • Investigate six phthalates near an industry and a

  18. Laboratory and field evaluation of the gas treatment approach for insitu remediation of chromate-contaminated soils

    Thornton, E.C.; Jackson, R.L.

    1994-04-01

    Laboratory scale soil treatment tests have been conducted as part of an effort to develop and implement an in situ chemical treatment approach to the remediation of chromate-contaminated soils through the use of reactive gases. These tests involved three different soil samples that were contaminated with Cr(VI) at the 200 ppM level. Treatment of the contaminated soils was performed by passing 100 ppM and 2000 ppM concentrations of hydrogen sulfide in nitrogen through soil columns until a S:Cr mole ratio of 10:1 was achieved. The treated soils were then leached with groundwater or deionized water and analyzed to assess the extent of chromium immobilization. Test results indicate >90% immobilization of chromium and demonstrate that the treatment process is irreversible. Ongoing developmental efforts are being directed towards the demonstration and evaluation of the gas treatment approach in a field test at a chromate-contaminated site. Major planned activities associated with this demonstration include laboratory testing of waste site soil samples, design of the treatment system and injection/extraction well network, geotechnical and geochemical characterization of the test site, and identification and resolution of regulatory and safety requirements

  19. Seasonal Variation in Soil Greenhouse Gas Emissions at Three Age-Stages of Dawn Redwood (Metasequoia glyptostroboides Stands in an Alluvial Island, Eastern China

    Shan Yin

    2016-11-01

    Full Text Available Greenhouse gas (GHG emissions are an important part of the carbon (C and nitrogen (N cycle in forest soil. However, soil greenhouse gas emissions in dawn redwood (Metasequoia glyptostroboides stands of different ages are poorly understood. To elucidate the effect of plantation age and environmental factors on soil GHG emissions, we used static chamber/gas chromatography (GC system to measure soil GHG emissions in an alluvial island in eastern China for two consecutive years. The soil was a source of CO2 and N2O and a sink of CH4 with annual emissions of 5.5–7.1 Mg C ha−1 year−1, 0.15–0.36 kg N ha−1 year−1, and 1.7–4.5 kg C ha−1 year−1, respectively. A clear exponential correlation was found between soil temperature and CO2 emission, but a negative linear correlation was found between soil water content and CO2 emission. Soil temperature had a significantly positive effect on CH4 uptake and N2O emission, whereas no significant correlation was found between CH4 uptake and soil water content, and N2O emission and soil water content. These results implied that older forest stands might cause more GHG emissions from the soil into the atmosphere because of higher litter/root biomass and soil carbon/nitrogen content compared with younger stands.

  20. Studies of soil and ecohydrological processes in oil-gas production regions.

    Khodyreva, E. Ya.; Khodyrev, Yu. P.

    2009-04-01

    For a better understanding and describing of the functional interactions between processes in soil and drinking, underground and stratum waters in oil-gas production regions we used laboratory and field monitoring methods of studies. The control of ecological situation dynamics in oil-gas production regions proposes a presence of primary data about parameter-indicators, which characterize a state of the object under investigation. One of these parameters is the concentration of heavy metal salts in drinking and stratum waters. Isolation of some compounds, which are extracted as impurities of oil and water during recovery of hydrocarbons from productive horizons, would enhance profitableness of recovery. Because accompanying impurities are a mixture of different salts and complexes, the methods of multielement analysis give the most objective evaluation of total content of some elements by search and prospecting. The developed method of laser mass-spectrometric analysis of oil and drinking, underground and industrial waters allows to investigate the samples on all elements of the periodical system simultaneously with limit sensitivity 0.1 mkg/l. The preparation of the oil and water probes was carried out by sublimation of highly volatile fractions in vacuum at 100 0C. The samples of drinking and underground waters, oils and industrial waters from wells of oil field Romashkin (Tatarstan) were chosen as the object for the research. In respect to possible metal extraction scandium is of most interest in inspected area because it's very high cost and availability of water-soluble pattern, most probably chloride. Its concentration in one well was 1 mg/l in water and 0.01 mg/l in oil. According to the received data of laser mass-spectrometric analysis, industrial waters on the activity investigated territory joint-stock company "Tatneft" contain 220-330 kg / ton of salts of metals that does by their potential source of alternative raw material for the chemical industry

  1. Uncertainty in 14C model ages of groundwater: The influence of soil gas in terranes dominated by C3 plants

    Nelson, S.; Hart, R.; Eggett, D.

    2009-12-01

    Groundwater is the largest source of fresh water readily available to humanity and aquifers with long residence times are particularly susceptible to overuse. Thus, it is important to have quantitative estimates of the residence time of water in such aquifers. Many models used to calculate 14C ages of groundwater depend on an estimate of the δ13C value of carbon dioxide in soil at the time of recharge, a value that must be estimated. Other work has suggested that for terranes dominated by C3 plants, -23‰ is an appropriate value, and sensitivity calculations show that the apparent age of a groundwater is strongly dependent on the choice of this parameter. This is especially true where the measured values of δ13C of dissolved inorganic carbon (DIC) are used to estimate the contribution of “dead” carbon to the DIC load via the dissolution of calcite in the aquifer and soil zones. To better understand the temporal and spatial isotopic and abundance variability of soil carbon dioxide, we established soil gas sampling sites that encompassed a wide variety of settings in terms of season, elevation, climate, and plant community that were sampled monthly throughout regions of the state of Utah where C3 flora dominate. Direct measurements of soil gas suggest a value of -21.8 ± 1.4‰ (1σ) is a good input variable as long as: a) C3 vegetation dominates, and b) extreme aridity does not prevail such that plant densities and soil microbial activities are minimized. If recharge is envisaged to occur during spring and early summer in highly vegetated uplands, a value of -24.0 ± 0.6‰ may be more appropriate as statistical analysis reveals that seasonality and plant density are most clearly correlated to the carbon isotope composition of carbon dioxide in soil gas. Although the two values and ranges cited above values do not diverge strongly from other published estimates, they place fairly narrow limits on the uncertainty of ±500 and ±200 yr., respectively, in

  2. Impacts of soil incorporation of pre-incubated silica-rich rice residue on soil biogeochemistry and greenhouse gas fluxes under flooding and drying.

    Gutekunst, Madison Y; Vargas, Rodrigo; Seyfferth, Angelia L

    2017-09-01

    Incorporation of silica-rich rice husk residue into flooded paddy soil decreases arsenic uptake by rice. However, the impact of this practice on soil greenhouse gas (GHG) emissions and elemental cycling is unresolved particularly as amended soils experience recurrent flooding and drying cycles. We evaluated the impact of pre-incubated silica-rich rice residue incorporation to soils on pore water chemistry and soil GHG fluxes (i.e., CO 2 , CH 4 , N 2 O) over a flooding and drying cycle typical of flooded rice cultivation. Soils pre-incubated with rice husk had 4-fold higher pore water Si than control and 2-fold higher than soils pre-incubated with rice straw, whereas the pore water As and Fe concentrations in soils amended with pre-incubated straw and husk were unexpectedly similar (maximum ~0.85μM and ~450μM levels, respectively). Pre-incubation of residues did not affect Si but did affect the pore water levels of As and Fe compared to previous studies using fresh residues where straw amended soils had higher As and Fe in pore water. The global warming potential (GWP) of soil GHG emissions decreased in the order straw (612±76g CO 2 -eqm -2 )>husk (367±42gCO 2 -eqm -2 )>ashed husk=ashed straw (251±26 and 278±28gCO 2 -eqm -2 )>control (186±23gCO 2 -eqm -2 ). The GWP increase due to pre-incubated straw amendment was due to: a) larger N 2 O fluxes during re-flooding; b) smaller contributions from larger CH 4 fluxes during flooded periods; and c) higher CH 4 and CO 2 fluxes at the onset of drainage. In contrast, the GWP of the husk amendment was dominated by CO 2 and CH 4 emissions during flooded and drainage periods, while ashed amendments increased CO 2 emissions particularly during drainage. This experiment shows that ashed residues and husk addition minimizes GWP of flooded soils and enhances pore water Si compared to straw addition even after pre-incubation. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Determination of Organophosphorus Pesticides in Soil by Dispersive Liquid–Liquid Microextraction and Gas Chromatography

    Yang, Zhonghua; Liu, Yu; Liu, Donghui; Zhou, Zhiqiang

    2012-01-01

    In this article, a rapid and sensitive sample pretreatment technique for the determination of organophosphorus pesticides (OPPs) in soil samples is developed by using dispersive liquid–liquid microextraction (DLLME) combined with gas chromatography–flame photometric detection. Experimental conditions, including the kind of extraction and disperser solvent and their volumes, the extraction time, and the salt addition, are investigated, and the following experiment factors are used: 20 µL chlorobenzene as the extraction solvent; 1.0 mL acetonitrile as the disperser solvent; no addition of salt; and an extraction time of 1 min. Under the optimum conditions, the linearities for the three target OPPs (ethoprophos, chlorpyriphos, and profenofos) are obtained by five points in the concentration range of 2.5–1500 µg/kg, and three replicates are used for each point. Correlation coefficients vary from 0.9987 to 0.9997. The repeatability is tested by spiking soil samples at a concentration level of 5.0 µg/kg. The relative standard deviation (n = 3) varied between 2.0% and 6.6%. The limits of detection, based on a signal-to-noise ratio (S/N) of 3, range from 200 to 500 pg/g. This method is applied to the analysis of the spiked samples S1, S2, and S3, which are collected from the China Agriculture University's orchard, lawn, and garden, respectively. The recoveries for each target analyte are in the range between 87.9% and 108.0%, 87.4% and 108.0%, and 86.7% and 107.2%, respectively. PMID:22291051

  4. Water and nitrogen management effects on semiarid sorghum production and soil trace gas flux under future climate.

    Duval, Benjamin D; Ghimire, Rajan; Hartman, Melannie D; Marsalis, Mark A

    2018-01-01

    External inputs to agricultural systems can overcome latent soil and climate constraints on production, while contributing to greenhouse gas emissions from fertilizer and water management inefficiencies. Proper crop selection for a given region can lessen the need for irrigation and timing of N fertilizer application with crop N demand can potentially reduce N2O emissions and increase N use efficiency while reducing residual soil N and N leaching. However, increased variability in precipitation is an expectation of climate change and makes predicting biomass and gas flux responses to management more challenging. We used the DayCent model to test hypotheses about input intensity controls on sorghum (Sorghum bicolor (L.) Moench) productivity and greenhouse gas emissions in the southwestern United States under future climate. Sorghum had been previously parameterized for DayCent, but an inverse-modeling via parameter estimation method significantly improved model validation to field data. Aboveground production and N2O flux were more responsive to N additions than irrigation, but simulations with future climate produced lower values for sorghum than current climate. We found positive interactions between irrigation at increased N application for N2O and CO2 fluxes. Extremes in sorghum production under future climate were a function of biomass accumulation trajectories related to daily soil water and mineral N. Root C inputs correlated with soil organic C pools, but overall soil C declined at the decadal scale under current weather while modest gains were simulated under future weather. Scaling biomass and N2O fluxes by unit N and water input revealed that sorghum can be productive without irrigation, and the effect of irrigating crops is difficult to forecast when precipitation is variable within the growing season. These simulation results demonstrate the importance of understanding sorghum production and greenhouse gas emissions at daily scales when assessing annual

  5. Temporal variation of soil gas compositions for earthquake surveillance in Taiwan

    Walia, Vivek; Yang, Tsanyao Frank; Lin, Shih-Jung; Kumar, Arvind; Fu, Ching-Chou; Chiu, Jun-Ming; Chang, Hsaio-Hsien; Wen, Kuo-Liang; Chen, Cheng-Hong

    2013-01-01

    The present study is proposed to investigate temporal variations of soil–gas composition in the vicinity of different fault zones in Taiwan. To carry out the investigations, variations of soil–gases compositions were measured at continuous earthquake monitoring stations along Hsincheng and Hsinhua faults in Hsinchu and Tainan areas, respectively. Before selecting a monitoring site, the occurrence of deeper gas emanation was investigated by the soil–gas surveys and followed by continuous monitoring of some selected sites with respect to tectonic activity to check the sensitivity of the sites. Based on the results of long term geochemical monitoring at the established monitoring stations we can divide the studied area in two different tectonic zones. We proposed tectonic based model for earthquake forecasting in Taiwan and tested it for some big earthquakes occurred during observation period i.e. 2009–2010. Based on the anomalous signatures from particular monitoring stations we are in a state to identify the area for impending earthquakes of magnitude ≥5 and we have tested it for some earthquakes which rocked the country during that period. It can be concluded from above results that the stress/strain transmission for a particular earthquake is hindered by different tectonic settings of the region under study. - Highlights: ► Variations of soil–gases composition is studied at two different faults of Taiwan. ► Tectonic based model for earthquake forecasting in Taiwan was proposed and tested. ► Selection criteria to identify threshold earthquakes have been defined. ► Stress/strain transmission for earthquake may be hindered by tectonic settings

  6. Response of Soil Biogeochemistry to Freeze-thaw Cycles: Impacts on Greenhouse Gas Emission and Nutrient Fluxes

    Rezanezhad, F.; Parsons, C. T.; Smeaton, C. M.; Van Cappellen, P.

    2014-12-01

    Freeze-thaw is an abiotic stress applied to soils and is a natural process at medium to high latitudes. Freezing and thawing processes influence not only the physical properties of soil, but also the metabolic activity of soil microorganisms. Fungi and bacteria play a crucial role in soil organic matter degradation and the production of greenhouse gases (GHG) such as CO2, CH4 and N2O. Production and consumption of these atmospheric trace gases are the result of biological processes such as photosynthesis, aerobic respiration (CO2), methanogenesis, methanotrophy (CH4), nitrification and denitrification (N2O). To enhance our understanding of the effects of freeze-thaw cycles on soil biogeochemical transformations and fluxes, a highly instrumented soil column experiment was designed to realistically simulate freeze-thaw dynamics under controlled conditions. Pore waters collected periodically from different depths of the column and solid-phase analyses on core material obtained at the initial and end of the experiment highlighted striking geochemical cycling. CO2, CH4 and N2O production at different depths within the column were quantified from dissolved gas concentrations in pore water. Subsequent emissions from the soil surface were determined by direct measurement in the head space. Pulsed CO2 emission to the headspace was observed at the onset of thawing, however, the magnitude of the pulse decreased with each subsequent freeze-thaw cycle indicating depletion of a "freeze-thaw accessible" carbon pool. Pulsed CO2 emission was due to a combination of physical release of gases dissolved in porewater and entrapped below the frozen zone and changing microbial respiration in response to electron acceptor variability (O2, NO3-, SO42-). In this presentation, we focus on soil-specific physical, chemical, microbial factors (e.g. redox conditions, respiration, fermentation) and the mechanisms that drive GHG emission and nutrient cycling in soils under freeze-thaw cycles.

  7. Modified technology in new constructions, and cost effective remedial action in existing structures, to prevent infiltration of soil gas carrying radon

    Ericson, S.O.; Schmied, H.; Clavensjoe, B.

    1984-01-01

    The general principles and mechanism of how soil gas infiltrates and carries radon from the foundation bed and subsoil into buildings are discussed. The Swedish Building Research Council has funded experiments and evaluation of cost effective remedial actions. The work has concerned existing dwellings with high concentration of radon, resulting from infiltrating soil gas and/or exhalation from building materials. A review and evaluation is given of experience and results acquired up to the summer of 1984. 100 dwellings have been constructed with consideration of possible infiltration of soil gas. In general minor modifications are sufficient to prevent infiltration. (Author)

  8. Nitrogen availability and indirect measurements of greenhouse gas emissions from aerobic and anaerobic biowaste digestates applied to agricultural soils

    Rigby, H.; Smith, S.R., E-mail: s.r.smith@imperial.ac.uk

    2013-12-15

    , indicating greater microbial activity in amended soil and reflecting the lower stability of this OM source, compared to the other, anaerobic digestate types, which showed no consistent effects on MBN compared to the control. Thus, the overall net release of digestate N in different soil types was not regulated by N transfer into the soil microbial biomass, but was determined primarily by digestate properties and the capacity of the soil type to process and turnover digestate N. In contrast to the sandy soil types, where nitrate (NO{sub 3}{sup -}) concentrations increased during incubation, there was an absence of NO{sub 3}{sup -} accumulation in the silty clay soil amended with LTAD and DMADMSW. This provided indirect evidence for denitrification activity and the gaseous loss of N, and the associated increased risk of greenhouse gas emissions under certain conditions of labile C supply and/or digestate physical structure in fine-textured soil types. The significance and influence of the interaction between soil type and digestate stability and physical properties on denitrification processes in digestate-amended soils require urgent investigation to ensure management practices are appropriate to minimise greenhouse gas emissions from land applied biowastes.

  9. Nitrogen availability and indirect measurements of greenhouse gas emissions from aerobic and anaerobic biowaste digestates applied to agricultural soils

    Rigby, H.; Smith, S.R.

    2013-01-01

    , indicating greater microbial activity in amended soil and reflecting the lower stability of this OM source, compared to the other, anaerobic digestate types, which showed no consistent effects on MBN compared to the control. Thus, the overall net release of digestate N in different soil types was not regulated by N transfer into the soil microbial biomass, but was determined primarily by digestate properties and the capacity of the soil type to process and turnover digestate N. In contrast to the sandy soil types, where nitrate (NO 3 - ) concentrations increased during incubation, there was an absence of NO 3 - accumulation in the silty clay soil amended with LTAD and DMADMSW. This provided indirect evidence for denitrification activity and the gaseous loss of N, and the associated increased risk of greenhouse gas emissions under certain conditions of labile C supply and/or digestate physical structure in fine-textured soil types. The significance and influence of the interaction between soil type and digestate stability and physical properties on denitrification processes in digestate-amended soils require urgent investigation to ensure management practices are appropriate to minimise greenhouse gas emissions from land applied biowastes

  10. Episodic radon changes in subsurface soil gas along active faults and possible relation to earthquakes

    King, C.

    1980-01-01

    Subsurface soil gas along active faults in central California has been continuously monitored by the Track Etch method to test whether its radon-isotope content may show any premonitory changes useful for earthquake prediction. The monitoring network was installed in May 1975 and has since been gradually expanded to consist of more than 60 stations along a 380-km section of the San Andreas fault system between Santa Rosa and Cholame. This network has recorded several episodes, each lasting several weeks to several months, during which the radon concentration increased by a factor of approximately 2 above average along some long, but limited, fault segments (approx.100 km). These episodes occurred in different seasons and do not appear to be systematically related to changes in meteorological conditions. However, they coincided reasonably well in time and space with larger local earthquakes above a threshold magnitude of about 4.0. These episodic radon changes may be caused by a changing outgassing rate in the fault zones in response to some episodic strain changes, which incidentally caused the earthquakes

  11. Mineral concentrations of forage legumes and grasses grown in acidic soil amended with flue gas desulfurization products

    Clark, R.B.; Baligar, V.C. [USDA ARS, Beltsville, MD (USA). Beltsville Agricultural Research Center West

    2003-07-01

    Considerable quantities of flue gas desulfurization products (FGDs) are generated when coal is burned for production of electricity, and these products have the potential to be reused rather than discarded. Use of FGDs as soil amendments could be important in overall management of these products, especially on acidic soils. Glasshouse studies were conducted to determine shoot concentrations of calcium (Ca), sulfur (S), potassium (K), magnesium (Mg), phosphorus (P), boron (B), zinc (Zn), copper (Cu), manganese (Mn), iron (Fe), aluminum (Al), sodium (Na), molybdenum (Mo), nickel (Ni), cadmium (Cd), chromium (Cr), and lead (Pb) in alfalfa (Medicago sativa), white clover (Trifolium repens), orchardgrass (Dacrylis glomerata), tall fescue (Festuca arundinacea), switchgrass (Panicum virgatum), and eastern gamagrass (Tripsacum dactyloides) grown in acidic (pH 4) soil (Typic Hapludult) amended with various levels of three FGDs and the control compounds CaCO{sub 3}, CaSO{sub 3}, and CaSO{sub 4}. Shoot concentrations of Ca, S, Mg, and B generally increased as levels of soil applied FGD increased. Concentrations of Mn, Fe, Zn, Cu were lower in shoots, especially when soil pH was high ({gt}7). Shoot concentrations of the trace elements Mo, Ni, Cd, Cr, and Pb were not above those reported as normal for foliage. Overall concentrations of most minerals remained near normal for shoots when plants were grown in FGD amended acidic soil.

  12. U.S. Geological Survey programs and investigations related to soil and water conservation

    Osterkamp, W.R.; Gray, J.R.

    2001-01-01

    The U.S. Geological Survey has a rich tradition of collecting hydrologic data, especially for fluxes of water and suspended sediment, that provide a foundation for studies of soil and water conservation. Applied and basic research has included investigations of the effects of land use on rangelands, croplands, and forests; hazards mapping; derivation of flood and drought frequency, and other statistics related to streamflow and reservoir storage; development and application of models of rainfall-runoff relations, chemical quality, and sediment movement; and studies of the interactive processes of overland and channel flow with vegetation. Networks of streamgaging stations and (or) sampling sites within numerous drainage basins are yielding information that extends databases and enhances the ability to use those data for interpretive studies.

  13. Topographical survey and soil characterization of a candidate site for Radioactive Waste Repository

    Peconick, Diva Godoi de O.; Mourao, Rogerio P., E-mail: godiva@cdtn.br, E-mail: mouraor@cdtn.br [Centro de Desenvolvimento da Tecnologia Nucelar (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2015-07-01

    Brazil has already initiated the establishment of a national near-surface repository for the low- and intermediate short-lived radioactive wastes generated within its territory. With two nuclear power plants in operation and a third one under construction, five active nuclear research institutes and another one planned for the intermediate future, operational constraints and social pressure built up for a disposal solution for such a waste category. The Brazilian Nuclear Commission CNEN was tasked at designing, building and commissioning this repository, which implies, among other activities, finding a suitable place for the facility. After an initial technical desk job, a federal land, not far from the NPPs, was appointed and in situ studies for the site characterization were started. This paper describes the topographical survey and soil drilling campaign carried out for the initial evaluation of the feasibility of the site vis-a-vis the applicable national regulations for site selection and disposal facilities licensing. (author)

  14. Topographical survey and soil characterization of a candidate site for Radioactive Waste Repository

    Peconick, Diva Godoi de O.; Mourao, Rogerio P.

    2015-01-01

    Brazil has already initiated the establishment of a national near-surface repository for the low- and intermediate short-lived radioactive wastes generated within its territory. With two nuclear power plants in operation and a third one under construction, five active nuclear research institutes and another one planned for the intermediate future, operational constraints and social pressure built up for a disposal solution for such a waste category. The Brazilian Nuclear Commission CNEN was tasked at designing, building and commissioning this repository, which implies, among other activities, finding a suitable place for the facility. After an initial technical desk job, a federal land, not far from the NPPs, was appointed and in situ studies for the site characterization were started. This paper describes the topographical survey and soil drilling campaign carried out for the initial evaluation of the feasibility of the site vis-a-vis the applicable national regulations for site selection and disposal facilities licensing. (author)

  15. Spatiotemporal dynamics of phosphorus release, oxygen consumption and greenhouse gas emissions after localised soil amendment with organic fertilisers

    Christel, Wibke [Department for Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C (Denmark); Department of Commerce, Industry and Agriculture, Danish Environmental Protection Agency, 1401 Copenhagen C (Denmark); Zhu, Kun [Department for Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C (Denmark); College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China); Hoefer, Christoph [Rhizosphere Ecology and Biogeochemistry Group, Department of Forest and Soil Sciences, University of Natural Resources and Life Sciences, Vienna, Konrad-Lorenz-Strasse 24, 3430 Tulln (Austria); Kreuzeder, Andreas [Rhizosphere Ecology and Biogeochemistry Group, Department of Forest and Soil Sciences, University of Natural Resources and Life Sciences, Vienna, Konrad-Lorenz-Strasse 24, 3430 Tulln (Austria); Land Salzburg, Natur- und Umweltschutz, Gewerbe (Abteilung 5), Michael-Pacher-Straße 36, 5020 Salzburg (Austria); Santner, Jakob [Rhizosphere Ecology and Biogeochemistry Group, Department of Forest and Soil Sciences, University of Natural Resources and Life Sciences, Vienna, Konrad-Lorenz-Strasse 24, 3430 Tulln (Austria); Division of Agronomy, Department of Crop Sciences, University of Natural Resources and Life Sciences, Vienna, Konrad-Lorenz-Strasse 24, 3430 Tulln (Austria); Bruun, Sander; Magid, Jakob [Department for Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C (Denmark); Jensen, Lars Stoumann, E-mail: lsj@plen.ku.dk [Department for Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C (Denmark)

    2016-06-01

    Organic fertilisation inevitably leads to heterogeneous distribution of organic matter and nutrients in soil, i.e. due to uneven surface spreading or inhomogeneous incorporation. The resulting localised hotspots of nutrient application will induce various biotic and abiotic nutrient turnover processes and fixation in the residuesphere, giving rise to distinct differences in nutrient availability, soil oxygen content and greenhouse gas (GHG) production. In this study we investigated the spatiotemporal dynamics of the reaction of manure solids and manure solids char with soil, focusing on their phosphorus (P) availability, as current emphasis on improving societal P efficiency through recycling waste or bio-based fertilisers necessitates a sound understanding of their behaviour. Soil layers amended at a constant P application rate with either pig manure solids or char made from pig manure solids were incubated for three weeks between layers of non-amended, P-depleted soil. Spatial and temporal changes in and around the amendment layers were simultaneously investigated in this study using a sandwich sensor consisting of a planar oxygen optode and multi-element diffusive gradients in thin films (DGT) gels, combined with GHG emission measurements. After three weeks of incubation, the soil containing a layer amended with manure solids had a lower overall O{sub 2} content and had emitted significantly more CO{sub 2} than the non-amended control or the char-amended soil. The P availability from manure solids was initially higher than that from the char, but decreased over time, whereas from the char-amended layer P availability increased in the same period. In both treatments, increases in P availability were confined to the amended soil layer and did not greatly affect P availability in the directly adjacent soil layers during the three-week incubation. These results highlight the importance of placing organic P fertilisers close to where the plant roots will grow in

  16. Spatiotemporal dynamics of phosphorus release, oxygen consumption and greenhouse gas emissions after localised soil amendment with organic fertilisers

    Christel, Wibke; Zhu, Kun; Hoefer, Christoph; Kreuzeder, Andreas; Santner, Jakob; Bruun, Sander; Magid, Jakob; Jensen, Lars Stoumann

    2016-01-01

    Organic fertilisation inevitably leads to heterogeneous distribution of organic matter and nutrients in soil, i.e. due to uneven surface spreading or inhomogeneous incorporation. The resulting localised hotspots of nutrient application will induce various biotic and abiotic nutrient turnover processes and fixation in the residuesphere, giving rise to distinct differences in nutrient availability, soil oxygen content and greenhouse gas (GHG) production. In this study we investigated the spatiotemporal dynamics of the reaction of manure solids and manure solids char with soil, focusing on their phosphorus (P) availability, as current emphasis on improving societal P efficiency through recycling waste or bio-based fertilisers necessitates a sound understanding of their behaviour. Soil layers amended at a constant P application rate with either pig manure solids or char made from pig manure solids were incubated for three weeks between layers of non-amended, P-depleted soil. Spatial and temporal changes in and around the amendment layers were simultaneously investigated in this study using a sandwich sensor consisting of a planar oxygen optode and multi-element diffusive gradients in thin films (DGT) gels, combined with GHG emission measurements. After three weeks of incubation, the soil containing a layer amended with manure solids had a lower overall O_2 content and had emitted significantly more CO_2 than the non-amended control or the char-amended soil. The P availability from manure solids was initially higher than that from the char, but decreased over time, whereas from the char-amended layer P availability increased in the same period. In both treatments, increases in P availability were confined to the amended soil layer and did not greatly affect P availability in the directly adjacent soil layers during the three-week incubation. These results highlight the importance of placing organic P fertilisers close to where the plant roots will grow in order to

  17. An Excel®-based visualization tool of 2-D soil gas concentration profiles in petroleum vapor intrusion.

    Verginelli, Iason; Yao, Yijun; Suuberg, Eric M

    2016-01-01

    In this study we present a petroleum vapor intrusion tool implemented in Microsoft ® Excel ® using Visual Basic for Applications (VBA) and integrated within a graphical interface. The latter helps users easily visualize two-dimensional soil gas concentration profiles and indoor concentrations as a function of site-specific conditions such as source strength and depth, biodegradation reaction rate constant, soil characteristics and building features. This tool is based on a two-dimensional explicit analytical model that combines steady-state diffusion-dominated vapor transport in a homogeneous soil with a piecewise first-order aerobic biodegradation model, in which rate is limited by oxygen availability. As recommended in the recently released United States Environmental Protection Agency's final Petroleum Vapor Intrusion guidance, a sensitivity analysis and a simplified Monte Carlo uncertainty analysis are also included in the spreadsheet.

  18. Soil properties, crop production and greenhouse gas emissions from organic and inorganic fertilizer-based arable cropping systems

    Chirinda, Ngonidzashe; Olesen, Jørgen Eivind; Porter, John Roy

    2010-01-01

    Organic and conventional farming practices differ in the use of several management strategies, including use of catch crops, green manure, and fertilization, which may influence soil properties, greenhouse gas emissions and productivity of agroecosystems. An 11-yr-old field experiment on a sandy...... loam soil in Denmark was used to compare several crop rotations with respect to a range of physical, chemical and biological characteristics related to carbon (C) and nitrogen (N) flows. Four organic rotations and an inorganic fertilizer-based system were selected to evaluate effects of fertilizer type...... growth was monitored and grain yields measured at harvest maturity. The different management strategies between 1997 and 2007 led to soil carbon inputs that were on average 18–68% and 32–91% higher in the organic than inorganic fertilizer-based rotations for the sampled winter wheat and spring barley...

  19. Estimating release of polycyclic aromatic hydrocarbons from coal-tar contaminated soil at manufactured gas plant sites. Final report

    Lee, L.S.

    1998-04-01

    One of EPRI's goals regarding the environmental behavior of organic substances consists of developing information and predictive tools to estimate the release potential of polycyclic aromatic hydrocarbons (PAHs) from contaminated soils at manufactured gas (MGP) plant sites. A proper assessment of the distribution of contaminants under equilibrium conditions and the potential for mass-transfer constraints is essential in evaluating the environmental risks of contaminants in the subsurface at MGP sites and for selecting remediation options. The results of this research provide insights into estimating maximum release concentrations of PAHs from MGP soils that have been contaminated by direct contact with the tar or through years of contact with contaminated groundwater. Attention is also given to evaluating the use of water-miscible cosolvents for estimating aqueous phase concentrations, and assessing the role of mass-transfer constraints in the release of PAHs from MGP site soils

  20. Measurement of air and VOC vapor fluxes during gas-driven soil remediation: bench-scale experiments.

    Kim, Heonki; Kim, Taeyun; Shin, Seungyeop; Annable, Michael D

    2012-09-04

    In this laboratory study, an experimental method was developed for the quantitative analyses of gas fluxes in soil during advective air flow. One-dimensional column and two- and three-dimensional flow chamber models were used in this study. For the air flux measurement, n-octane vapor was used as a tracer, and it was introduced in the air flow entering the physical models. The tracer (n-octane) in the gas effluent from the models was captured for a finite period of time using a pack of activated carbon, which then was analyzed for the mass of n-octane. The air flux was calculated based on the mass of n-octane captured by the activated carbon and the inflow concentration. The measured air fluxes are in good agreement with the actual values for one- and two-dimensional model experiments. Using both the two- and three-dimensional models, the distribution of the air flux at the soil surface was measured. The distribution of the air flux was found to be affected by the depth of the saturated zone. The flux and flux distribution of a volatile contaminant (perchloroethene) was also measured by using the two-dimensional model. Quantitative information of both air and contaminant flux may be very beneficial for analyzing the performance of gas-driven subsurface remediation processes including soil vapor extraction and air sparging.

  1. Rich soil carbon and nitrogen but low atmospheric greenhouse gas fluxes from North Sulawesi mangrove swamps in Indonesia.

    Chen, Guang C; Ulumuddin, Yaya I; Pramudji, Sastro; Chen, Shun Y; Chen, Bin; Ye, Yong; Ou, Dan Y; Ma, Zhi Y; Huang, Hao; Wang, Jing K

    2014-07-15

    The soil to atmosphere fluxes of greenhouse gases N2O, CH4 and CO2 and their relationships with soil characteristics were investigated in three tropical oceanic mangrove swamps (Teremaal, Likupang and Kema) in North Sulawesi, Indonesia. Mangrove soils in North Sulawesi were rich in organic carbon and nitrogen, but the greenhouse gas fluxes were low in these mangroves. The fluxes ranged -6.05-13.14 μmol m(-2)h(-1), -0.35-0.61 μmol m(-2)h(-1) and -1.34-3.88 mmol m(-2)h(-1) for N2O, CH4 and CO2, respectively. The differences in both N2O and CH4 fluxes among different mangrove swamps and among tidal positions in each mangrove swamp were insignificant. CO2 flux was influenced only by mangrove swamps and the value was higher in Kema mangrove. None of the measured soil parameters could explain the variation of CH4 fluxes among the sampling plots. N2O flux was negatively related to porewater salinity, while CO2 flux was negatively correlated with water content and organic carbon. This study suggested that the low gas emissions due to slow metabolisms would lead to the accumulations of organic matters in North Sulawesi mangrove swamps. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Nationwide cross-sectional survey of schistosomiasis and soil-transmitted helminthiasis in Sudan: study protocol.

    Cha, Seungman; Hong, Sung-Tae; Lee, Young-Ha; Lee, Keon Hoon; Cho, Dae Seong; Lee, Jinmoo; Chai, Jong-Yil; Elhag, Mousab Siddig; Khaled, Soheir Gabralla Ahmad; Elnimeiri, Mustafa Khidir Mustafa; Siddig, Nahid Abdelgadeir Ali; Abdelrazig, Hana; Awadelkareem, Sarah; Elshafie, Azza Tag Eldin; Ismail, Hassan Ahmed Hassan Ahmed; Amin, Mutamad

    2017-09-12

    Schistosomiasis and soil-transmitted helminthiasis (STHs) are target neglected tropical diseases (NTDs) of preventive chemotherapy, but the control and elimination of these diseases have been impeded due to resource constraints. Few reports have described study protocol to draw on when conducting a nationwide survey. We present a detailed methodological description of the integrated mapping of schistosomiasis and STHs on the basis of our experiences, hoping that this protocol can be applied to future surveys in similar settings. In addition to determining the ecological zones requiring mass drug administration interventions, we aim to provide precise estimates of the prevalence of these diseases. A school-based cross-sectional design will be applied for the nationwide survey across Sudan. The survey is designed to cover all districts in every state. We have divided each district into 3 different ecological zones depending on proximity to bodies of water. We will employ a probability-proportional-to-size sampling method for schools and systematic sampling for student selection to provide adequate data regarding the prevalence for schistosomiasis and STHs in Sudan at the state level. A total of 108,660 students will be selected from 1811 schools across Sudan. After the survey is completed, 391 ecological zones will be mapped out. To carry out the survey, 655 staff members were recruited. The feces and urine samples are microscopically examined by the Kato-Katz method and the sediment smears for helminth eggs respectively. For quality control, a minimum of 10% of the slides will be rechecked by the federal supervisors in each state and also 5% of the smears are validated again within one day by independent supervisors. This nationwide mapping is expected to generate important epidemiological information and indicators about schistosomiasis and STHs that will be useful for monitoring and evaluating the control program. The mapping data will also be used for overviewing

  3. Geophysical surveys combined with laboratory soil column experiments to identify and explore risk areas for soil and water pollution in feedlots

    Espejo-Pérez, Antonio Jesus; Sainato, Claudia Mabel; Jairo Márquez-Molina, John; Giráldez, Juan Vicente; Vanderlinden, Karl

    2014-05-01

    Changes of land use without a correct planning may produce its deterioration with their social, economical and environmental irreversible consequences over short to medium time range. In Argentina, the expansion of soybean fields induced a reduction of the area of pastures dedicated to stockbreeding. As cattle activity is being progressively concentrated on small pens, at feedlots farms, problems of soil and water pollution, mainly by nitrate, have been detected. The characterization of the spatial and temporal variability of soil water content is very important because the mostly advective transport of solutes. To avoid intensive soil samplings, very expensive, one has to recur to geophysical exploration methods. The objective of this work was to identify risk areas within a feedlot of the NW zone of Buenos Aires Province, in Argentina through geophysical methods. The surveys were carried out with an electromagnetic induction profiler EMI-400 (GSSI) and a Time domain Reflectometry (TDR) survey of depth 0-0.10 m with soil sampling and measurement of moisture content with gravimetric method (0-1.0 m). Several trenches were dug inside the pens and also at a test site, where texture, apparent density, saturated hydraulic conductivity (Ks), electrical conductivity of the saturation paste extract and organic matter content (OM) were measured. The water retention curves for these soils were also determined. At one of the pens undisturbed soil columns were extracted at 3 locations. Laboratory analysis for 0-1.0 m indicated that soil texture was classified as sandy loam, average organic matter content (OM) was greater than 2.3% with low values of apparent density in the first 10 cm. The range of spatial dependence of data suggested that the number of soil samples could be reduced. Soil apparent electrical conductivity (ECa) and soil moisture were well correlated and indicated a clear spatial pattern in the corrals. TDR performance was acceptable to identify the spatial

  4. Generalized Density-Corrected Model for Gas Diffusivity in Variably Saturated Soils

    Chamindu, Deepagoda; Møldrup, Per; Schjønning, Per

    2011-01-01

    models. The GDC model was further extended to describe two-region (bimodal) soils and could describe and predict Dp/Do well for both different soil aggregate size fractions and variably compacted volcanic ash soils. A possible use of the new GDC model is engineering applications such as the design...... of highly compacted landfill site caps....

  5. Shocked POststarburst Galaxy Survey. II. The Molecular Gas Content and Properties of a Subset of SPOGs

    Alatalo, Katherine; Lisenfeld, Ute; Lanz, Lauranne; Appleton, Philip N.; Ardila, Felipe; Cales, Sabrina L.; Kewley, Lisa J.; Lacy, Mark; Medling, Anne M.; Nyland, Kristina; Rich, Jeffrey A.; Urry, C. Meg

    2016-08-01

    We present CO(1-0) observations of objects within the Shocked POststarburst Galaxy Survey taken with the Institut de Radioastronomie Millimétrique 30 m single dish and the Combined Array for Research for Millimeter Astronomy interferometer. Shocked poststarburst galaxies (SPOGs) represent a transitioning population of galaxies, with deep Balmer absorption ({{EW}}{{H}δ }\\gt 5 {\\mathring{{A}}} ), consistent with an intermediate-age (A-star) stellar population, and ionized gas line ratios inconsistent with pure star formation. The CO(1-0) subsample was selected from SPOGs detected by the Wide-field Infrared Survey Explorer with 22 μm flux detected at a signal-to-noise ratio (S/N) > 3. Of the 52 objects observed in CO(1-0), 47 are detected with S/N > 3. A large fraction (37%-46% ± 7%) of our CO-SPOG sample were visually classified as morphologically disrupted. The H2 masses detected were between {10}8.7-10.8 {M}⊙ , consistent with the gas masses found in normal galaxies, though approximately an order of magnitude larger than the range seen in poststarburst galaxies. When comparing the 22 μm and CO(1-0) fluxes, SPOGs diverge from the normal star-forming relation, having 22 μm fluxes in excess of the relation by a factor of ={4.91}-0.39+0.42, suggestive of the presence of active galactic nuclei (AGNs). The Na I D characteristics of CO-SPOGs show that it is likely that many of these objects host interstellar winds. Objects with large Na I D enhancements also tend to emit in the radio, suggesting possible AGN driving of neutral winds.

  6. A new survey method of tsunami inundation area using chemical analysis of soil. Application to the field survey on the 2010 Chilean tsunami at Chile

    Yoshii, Takumi; Matsuyama, Masafumi; Koshimura, Shunichi; Mas, Erick; Matsuoka, Masashi; Jimenez, Cesar

    2011-01-01

    The severe earthquake of Mw 8.8 occurred on 27 Feb. 2010 at the center of Chile. The tsunami generated by the earthquake attacked the coast of Chile and it propagated to the Pacific Ocean coastline. The field survey on the disaster damages due to the tsunami was conducted near Talcahuano in Chile to prepare for the great tsunamis accompanied by the earthquakes predicted to occur near Japan within several decades. The aims of this field survey were to survey disaster damages especially relevant to electric equipments and to develop the survey method based on a chemical analysis of the inundated soil which supplies objective data with high accuracy compared to the conventional methods. In the survey area, the average of inundation heights was 6 m, however it locally reached up to 25 m. The maximum sea-level height of the series of the tsunamis was recorded in the third or fourth wave (roughly 3 hours after the earthquake occurrence). The first floors of houses were severely destroyed and some ships were carried and left on land by the tsunamis. Furthermore, the large amount of sediment was deposited in towns. Removing the drifted ships and tsunami deposit is important consideration for quick recovery from a disaster due to a tsunami. The soil samples were obtained from both the inundated and the not-inundated position. The stirred solution was made by the soil and ultrapure water, then, the content of water-soluble ions, electric conductivity (EC), and pH were measured. The soil obtained in the tsunami inundated area contains much water-soluble ions (Na + , Mg 2+ , Cl - , Br - , SO 4 2- ) compared to the samples obtained in the not-inundated area. The discriminant analysis of the tsunami inundation was conducted using the amount of ions in the soil. High discriminant accuracy (over 90%) was obtained with Na + , Mg 2+ , Cl - , Br - , SO 4 2- and EC. Br - , Cl - , Na + are believed to be suitable for the discriminant analysis about tsunamis considering the contaminant

  7. Radon soil gas measurements in a geological versatile region as basis to improve the prediction of areas with a high radon potential

    Kabrt, Franz; Rechberger, Fabian; Schuff, Michael; Seidel, Claudia; Baumgartner, Andreas; Friedmann, Harry; Maringer, Franz Josef

    2014-01-01

    With the aim to predict the radon potential by geological data, radon soil gas measurements were made in a selected region in Styria, Austria. This region is characterised by mean indoor radon potentials of 130-280 Bq m -3 and a high geological diversity. The distribution of the individual measuring sites was selected on the basis of geological aspects and the distribution of area settlements. In this work, the radon soil gas activity concentration and the soil permeability were measured at 100 sites, each with three single measurements. Furthermore, the local dose rate was determined and soil samples were taken at each site to determine the activity concentration of natural radionuclides. During two investigation periods, long-term soil gas radon measurements were made to study the time dependency of the radon activity concentration. All the results will be compared and investigated for correlation among each other to improve the prediction of areas with high radon potential. (authors)

  8. Independent Verification Survey of the Clean Coral Storage Pile at the Johnston Atoll Plutonium Contaminated Soil Remediation Project

    Wilson-Nichols, M.J.; Egidi, P.V.; Roemer, E.K.; Schlosser, R.M.

    2000-01-01

    f I The Oak Ridge National Laboratory (ORNL) Environmental Technology Section conducted an independent verification (IV) survey of the clean storage pile at the Johnston Atoll Plutonium Contaminated Soil Remediation Project (JAPCSRP) from January 18-25, 1999. The goal of the JAPCSRP is to restore a 24-acre area that was contaminated with plutonium oxide particles during nuclear testing in the 1960s. The selected remedy was a soil sorting operation that combined radiological measurements and mining processes to identify and sequester plutonium-contaminated soil. The soil sorter operated from about 1990 to 1998. The remaining clean soil is stored on-site for planned beneficial use on Johnston Island. The clean storage pile currently consists of approximately 120,000 m3 of coral. ORNL conducted the survey according to a Sampling and Analysis Plan, which proposed to provide an IV of the clean pile by collecting a minimum number (99) of samples. The goal was to ascertain wi th 95% confidence whether 97% of the processed soil is less than or equal to the accepted guideline (500-Bq/kg or 13.5-pCi/g) total transuranic (TRU) activity

  9. The Green Bank Ammonia Survey: Observations of Hierarchical Dense Gas Structures in Cepheus-L1251

    Keown, Jared; Di Francesco, James; Kirk, Helen; Friesen, Rachel K.; Pineda, Jaime E.; Rosolowsky, Erik; Ginsburg, Adam; Offner, Stella S. R.; Caselli, Paola; Alves, Felipe; Chacón-Tanarro, Ana; Punanova, Anna; Redaelli, Elena; Seo, Young Min; Matzner, Christopher D.; Chun-Yuan Chen, Michael; Goodman, Alyssa A.; Chen, How-Huan; Shirley, Yancy; Singh, Ayushi; Arce, Hector G.; Martin, Peter; Myers, Philip C.

    2017-11-01

    We use Green Bank Ammonia Survey observations of NH3 (1, 1) and (2, 2) emission with 32″ FWHM resolution from a ˜10 pc2 portion of the Cepheus-L1251 molecular cloud to identify hierarchical dense gas structures. Our dendrogram analysis of the NH3 data results in 22 top-level structures, which reside within 13 lower-level parent structures. The structures are compact (0.01 {pc}≲ {R}{eff}≲ 0.1 {pc}) and are spatially correlated with the highest H2 column density portions of the cloud. We also compare the ammonia data to a catalog of dense cores identified by higher-resolution (18.″2 FWHM) Herschel Space Observatory observations of dust continuum emission from Cepheus-L1251. Maps of kinetic gas temperature, velocity dispersion, and NH3 column density, derived from detailed modeling of the NH3 data, are used to investigate the stability and chemistry of the ammonia-identified and Herschel-identified structures. We show that the dust and dense gas in the structures have similar temperatures, with median T dust and T K measurements of 11.7 ± 1.1 K and 10.3 ± 2.0 K, respectively. Based on a virial analysis, we find that the ammonia-identified structures are gravitationally dominated, yet may be in or near a state of virial equilibrium. Meanwhile, the majority of the Herschel-identified dense cores appear to be not bound by their own gravity and instead confined by external pressure. CCS (20 - 10) and HC5N (9-8) emission from the region reveal broader line widths and centroid velocity offsets when compared to the NH3 (1, 1) emission in some cases, likely due to these carbon-based molecules tracing the turbulent outer layers of the dense cores.

  10. CARMA LARGE AREA STAR FORMATION SURVEY: STRUCTURE AND KINEMATICS OF DENSE GAS IN SERPENS MAIN

    Lee, Katherine I.; Storm, Shaye; Mundy, Lee G.; Teuben, Peter; Pound, Marc W.; Salter, Demerese M.; Chen, Che-Yu [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Fernández-López, Manuel; Looney, Leslie W.; Segura-Cox, Dominique [Department of Astronomy, University of Illinois, Urbana-Champaign, IL 61801 (United States); Rosolowsky, Erik [Departments of Physics and Statistics, University of British Columbia, Okanagan Campus, 3333 University Way, Kelowna BC V1V 1V7 (Canada); Arce, Héctor G.; Plunkett, Adele L. [Department of Astronomy, Yale University, PO Box 208101, New Haven, CT 06520-8101 (United States); Ostriker, Eve C. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Shirley, Yancy L. [Steward Observatory, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Kwon, Woojin [SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen (Netherlands); Kauffmann, Jens [Max Planck Institut für Radioastronomie, Auf dem Hügel 69 D-53121, Bonn Germany (Germany); Tobin, John J. [National Radio Astronomy Observatory, Charlottesville, VA 22903 (United States); Volgenau, N. H. [Astronomy Department, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125 (United States); Tassis, Konstantinos, E-mail: ijlee9@astro.umd.edu [Department of Physics and Institute of Theoretical and Computational Physics, University of Crete, PO Box 2208, GR-710 03, Heraklion, Crete (Greece); and others

    2014-12-20

    We present observations of N{sub 2}H{sup +} (J = 1 → 0), HCO{sup +} (J = 1 → 0), and HCN (J = 1 → 0) toward the Serpens Main molecular cloud from the CARMA Large Area Star Formation Survey (CLASSy). We mapped 150 arcmin{sup 2} of Serpens Main with an angular resolution of ∼7''. The gas emission is concentrated in two subclusters (the NW and SE subclusters). The SE subcluster has more prominent filamentary structures and more complicated kinematics compared to the NW subcluster. The majority of gas in the two subclusters has subsonic to sonic velocity dispersions. We applied a dendrogram technique with N{sub 2}H{sup +}(1-0) to study the gas structures; the SE subcluster has a higher degree of hierarchy than the NW subcluster. Combining the dendrogram and line fitting analyses reveals two distinct relations: a flat relation between nonthermal velocity dispersion and size, and a positive correlation between variation in velocity centroids and size. The two relations imply a characteristic depth of 0.15 pc for the cloud. Furthermore, we have identified six filaments in the SE subcluster. These filaments have lengths of ∼0.2 pc and widths of ∼0.03 pc, which is smaller than a characteristic width of 0.1 pc suggested by Herschel observations. The filaments can be classified into two types based on their properties. The first type, located in the northeast of the SE subcluster, has larger velocity gradients, smaller masses, and nearly critical mass-per-unit-length ratios. The other type, located in the southwest of the SE subcluster, has the opposite properties. Several YSOs are formed along two filaments which have supercritical mass per unit length ratios, while filaments with nearly critical mass-per-unit-length ratios are not associated with YSOs, suggesting that stars are formed on gravitationally unstable filaments.

  11. Spatial effects of aboveground biomass on soil ecological parameters and trace gas fluxes in a savannah ecosystem of Mount Kilimanjaro

    Becker, Joscha; Gütlein, Adrian; Sierra Cornejo, Natalia; Kiese, Ralf; Hertel, Dietrich; Kuzyakov, Yakov

    2015-04-01

    The savannah biome is a hotspot for biodiversity and wildlife conservation in Africa and recently got in the focus of research on carbon sequestration. Savannah ecosystems are under strong pressure from climate and land-use change, especially around populous areas like the Mt. Kilimanjaro region. Savannah vegetation in this area consists of grassland with isolated trees and is therefore characterized by high spatial variation of canopy cover, aboveground biomass and root structure. Canopy structure is known to affect microclimate, throughfall and evapotranspiration and thereby controls soil moisture conditions. Consequently, the canopy structure is a major regulator for soil ecological parameters and soil-atmospheric trace gas exchange (CO2, N2O, CH4) in water limited environments. The spatial distribution of these parameters and the connection between above and belowground processes are important to understand and predict ecosystem changes and estimate its vulnerability. Our objective was to determine trends and changes of soil parameters and relate their spatial variability to the vegetation structure. We chose three trees from each of the two most dominant species (Acacia nilotica and Balanites aegyptiaca) in our research area. For each tree, we selected transects with nine sampling points of the same relative distances to the stem. Distances were calculated in relation to the crown radius. At these each sampling point a soil core was taken and separated in 0-10 cm and 10-30 cm depth. We measured soil carbon (C) and nitrogen (N) storage, microbial biomass carbon C and N, soil respiration as well as root biomass and -density, soil temperature and soil water content. Each tree was characterized by crown spread, leaf area index and basal area. Preliminary results show that C and N stocks decreased about 50% with depth independently of distance to the tree. Soil water content under the tree crown increased with depth while it decreased under grass cover. Microbial

  12. The hydraulic conductance of Fraxinus ornus leaves is constrained by soil water availability and coordinated with gas exchange rates.

    Gortan, Emmanuelle; Nardini, Andrea; Gascó, Antonio; Salleo, Sebastiano

    2009-04-01

    Leaf hydraulic conductance (Kleaf) is known to be an important determinant of plant gas exchange and photosynthesis. Little is known about the long-term impact of different environmental factors on the hydraulic construction of leaves and its eventual consequences on leaf gas exchange. In this study, we investigate the impact of soil water availability on Kleaf of Fraxinus ornus L. as well as the influence of Kleaf on gas exchange rates and plant water status. With this aim, Kleaf, leaf conductance to water vapour (gL), leaf water potential (Psileaf) and leaf mass per area (LMA) were measured in F. ornus trees, growing in 21 different sites with contrasting water availability. Plants growing in arid sites had lower Kleaf, gL and Psileaf than those growing in sites with higher water availability. On the contrary, LMA was similar in the two groups. The Kleaf values recorded in sites with two different levels of soil water availability were constantly different from each other regardless of the amount of precipitation recorded over 20 days before measurements. Moreover, Kleaf was correlated with gL values. Our data suggest that down-regulation of Kleaf is a component of adaptation of plants to drought-prone habitats. Low Kleaf implies reduced gas exchange which may, in turn, influence the climatic conditions on a local/regional scale. It is concluded that leaf hydraulics and its changes in response to resource availability should receive greater attention in studies aimed at modelling biosphere-atmosphere interactions.

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

    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

  14. Simulating the Fate and Transport of Coal Seam Gas Chemicals in Variably-Saturated Soils Using HYDRUS

    Dirk Mallants

    2017-05-01

    Full Text Available The HYDRUS-1D and HYDRUS (2D/3D computer software packages are widely used finite element models for simulating the one-, and two- or three-dimensional movement of water, heat, and multiple solutes in variably-saturated media, respectively. While the standard HYDRUS models consider only the fate and transport of individual solutes or solutes subject to first-order degradation reactions, several specialized HYDRUS add-on modules can simulate far more complex biogeochemical processes. The objective of this paper is to provide a brief overview of the HYDRUS models and their add-on modules, and to demonstrate possible applications of the software to the subsurface fate and transport of chemicals involved in coal seam gas extraction and water management operations. One application uses the standard HYDRUS model to evaluate the natural soil attenuation potential of hydraulic fracturing chemicals and their transformation products in case of an accidental release. By coupling the processes of retardation, first-order degradation and convective-dispersive transport of the biocide bronopol and its degradation products, we demonstrated how natural attenuation reduces initial concentrations by more than a factor of hundred in the top 5 cm of the soil. A second application uses the UnsatChem module to explore the possible use of coal seam gas produced water for sustainable irrigation. Simulations with different irrigation waters (untreated, amended with surface water, and reverse osmosis treated provided detailed results regarding chemical indicators of soil and plant health, notably SAR, EC and sodium concentrations. A third application uses the HP1 module to analyze trace metal transport involving cation exchange and surface complexation sorption reactions in a soil leached with coal seam gas produced water following some accidental water release scenario. Results show that the main process responsible for trace metal migration in soil is complexation of

  15. Dry flue gas desulfurization by-product application effects on plant uptake and soil storage changes in a managed grassland.

    Burgess-Conforti, Jason R; Brye, Kristofor R; Miller, David M; Pollock, Erik D; Wood, Lisa S

    2018-02-01

    Environmental regulations mandate that sulfur dioxide (SO 2 ) be removed from the flue gases of coal-fired power plants, which results in the generation of flue gas desulfurization (FGD) by-products. These FGD by-products may be a viable soil amendment, but the large amounts of trace elements contained in FGD by-products are potentially concerning. The objective of this study was to evaluate the effects of land application of a high-Ca dry FGD (DFGD) by-product on trace elements in aboveground biomass and soil. A high-Ca DFGD by-product was applied once at a rate of 9 Mg ha -1 on May 18, 2015 to small plots with mixed-grass vegetation. Soil and biomass were sampled prior to application and several times thereafter. Aboveground dry matter and tissue As, Co, Cr, Hg, Se, U, and V concentrations increased (P  0.05) from pre-application levels or the unamended control within 3 to 6 months of application. Soil pH in the amended treatment 6 months after application was greater (P by-product application compared to the unamended control. High-Ca DFGD by-products appear to be useful as a soil amendment, but cause at least a temporary increase in tissue concentrations of trace elements, which may be problematic for animal grazing situations.

  16. Remediation of saline-sodic soil with flue gas desulfurization gypsum in a reclaimed tidal flat of southeast China.

    Mao, Yumei; Li, Xiaping; Dick, Warren A; Chen, Liming

    2016-07-01

    Salinization and sodicity are obstacles for vegetation reconstruction of coastal tidal flat soils. A study was conducted with flue gas desulfurization (FGD)-gypsum applied at rates of 0, 15, 30, 45 and 60Mg/ha to remediate tidal flat soils of the Yangtze River estuary. Exchangeable sodium percentage (ESP), exchangeable sodium (ExNa), pH, soluble salt concentration, and composition of soluble salts were measured in 10cm increments from the surface to 30cm depth after 6 and 18months. The results indicated that the effect of FGD-gypsum is greatest in the 0-10cm mixing soil layer and 60Mg/ha was the optimal rate that can reduce the ESP to below 6% and decrease soil pH to neutral (7.0). The improvement effect was reached after 6months, and remained after 18months. The composition of soluble salts was transformed from sodic salt ions mainly containing Na(+), HCO3(-)+CO3(2-) and Cl(-) to neutral salt ions mainly containing Ca(2+) and SO4(2-). Non-halophyte plants were survived at 90%. The study demonstrates that the use of FGD-gypsum for remediating tidal flat soils is promising. Copyright © 2016. Published by Elsevier B.V.

  17. SIGGMA: A SURVEY OF IONIZED GAS IN THE GALAXY, MADE WITH THE ARECIBO TELESCOPE

    Liu, B. [National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); McIntyre, T. [University of New Mexico, Albuquerque, NM 87131 (United States); Terzian, Y. [Cornell University, Ithaca, NY 14853 (United States); Minchin, R. [Arecibo Observatory, HC03 Box 53995, Arecibo 00612, PR (United States); Anderson, L. [West Virginia University, Morgantown, WV 26506 (United States); Churchwell, E. [University of Wisconsin-Madison, Madison, WI 53706 (United States); Lebron, M. [University of Puerto Rico, P.O. Box 23323, 00931-3323, San Juan (Puerto Rico); Roshi, D. Anish [National Radio Astronomy Observatory, Green Bank and Charlottesville, VA 22903 (United States)

    2013-10-01

    A Survey of Ionized Gas in the Galaxy, made with the Arecibo telescope (SIGGMA), uses the Arecibo L-band Feed Array (ALFA) to fully sample the Galactic plane (30 Degree-Sign {<=} l {<=} 75 Degree-Sign and -2 Degree-Sign {<=} b {<=} 2 Degree-Sign ; 175 Degree-Sign {<=} l {<=} 207 Degree-Sign and -2 Degree-Sign {<=} b {<=} 1 Degree-Sign ) observable with the telescope in radio recombination lines (RRLs). Processed data sets are being produced in the form of data cubes of 2 Degree-Sign (along l) Multiplication-Sign 4 Degree-Sign (along b) Multiplication-Sign 151 (number of channels), archived and made public. The 151 channels cover a velocity range of 600 km s{sup -1} and the velocity resolution of the survey changes from 4.2 km s{sup -1} to 5.1 km s{sup -1} from the lowest frequency channel to the highest frequency channel. RRL maps with 3.'4 resolution and a line flux density sensitivity of {approx}0.5 mJy will enable us to identify new H II regions, measure their electron temperatures, study the physics of photodissociation regions with carbon RRLs, and investigate the origin of the extended low-density medium. Twelve Hn{alpha} lines fall within the 300 MHz bandpass of ALFA; they are resampled to a common velocity resolution to improve the signal-to-noise ratio (S/N) by a factor of three or more and preserve the line width. SIGGMA will produce the most sensitive fully sampled RRL survey to date. Here, we discuss the observing and data reduction techniques in detail. A test observation toward the H II region complex S255/S257 has detected Hn{alpha} and Cn{alpha} lines with S/N > 10.

  18. Analysis of petroleum-contaminated soils by diffuse reflectance spectroscopy and sequential ultrasonic solvent extraction–gas chromatography

    Okparanma, Reuben N.; Coulon, Frederic; Mouazen, Abdul M.

    2014-01-01

    In this study, we demonstrate that partial least-squares regression analysis with full cross-validation of spectral reflectance data estimates the amount of polycyclic aromatic hydrocarbons in petroleum-contaminated tropical rainforest soils. We applied the approach to 137 field-moist intact soil samples collected from three oil spill sites in Ogoniland in the Niger Delta province (5.317°N, 6.467°E), Nigeria. We used sequential ultrasonic solvent extraction–gas chromatography as the reference chemical method. We took soil diffuse reflectance spectra with a mobile fibre-optic visible and near-infrared spectrophotometer (350–2500 nm). Independent validation of combined data from studied sites showed reasonable prediction precision (root-mean-square error of prediction = 1.16–1.95 mg kg −1 , ratio of prediction deviation = 1.86–3.12, and validation r 2 = 0.77–0.89). This suggests that the methodology may be useful for rapid assessment of the spatial variability of polycyclic aromatic hydrocarbons in petroleum-contaminated soils in the Niger Delta to inform risk assessment and remediation. -- Highlights: • We model NIR diffuse reflectance spectra for PAH prediction in contaminated soils. • Soil diffuse reflectance decreases with increasing PAH concentration. • Mechanism of prediction relies on co-variation of PAH with other soil properties. • Positions of important wavelengths are largely similar for studied sites. • Positive regression coefficients around 1647 nm show a link to PAH. -- This approach may be used to collect large spatial data at reduced cost and time to assess the variability of polycyclic aromatic hydrocarbons in petroleum release sites

  19. Evaluation of a biodegradation screening protocol for contaminated soil from manufactured gas plant sites

    Morgan, D.J.; Battaglia, A.; Smith, J.R.; Middleton, A.C.; Nakles, D.V.; Linz, D.G.

    1991-01-01

    Bioremediation has been demonstrated to be a viable alternative for treating soils contaminated with PAHs. however, given the variability encountered in soils characteristics and contamination level, their susceptibility to biological treatment must be assessed on a case-by-case basis. This paper discusses a new treatability protocol, the GRI Accelerated Treatability Protocol. The mainstay of the protocol, which is designed to quickly provide treatability data for a given contaminated soil is a bioslurry experiment, in which the contaminated soil is continuously stirred and provided with abundant oxygen, nutrients and water, to maximize biological activity and thus contaminant removal. The results of using such protocol on four soils, widely differing in physical characteristics and contamination levels, are compared to the results of traditional pan studies, and an empirical equation, describing the observed soil concentrations as a function of time in both slurry and pans, is presented. Similarities and differences between achievable endpoints and biodegradation rates are discussed, and the applicability of the GRI Accelerated Treatability Protocol to full-scale engineered systems is addressed. Results to date indicate that, for soils with less than 10% fines slurry and pan experiments yield approximately the same endpoint, so that for those soils the GRI Accelerated Treatability Protocol can be used to assess the viability of an unsaturated bioremediation system. For soils with more than 10% fines, the slurry treatment endpoints are better than the pans. For those soils a traditional pan study experiment should be performed to evaluate the potential capabilities of unsaturated bioremediation

  20. Potential denitrification in arable soil samples at winter temperatures - measurements by 15N gas analysis

    Lippold, H.; Foerster, I.; Matzel, W.

    1989-01-01

    In samples from the plough horizon of five soils taken after cereal harvest, denitrification was measured as volatilization of N 2 and N 2 O from 15 N nitrate in the absence of O 2 . Nitrate contents lower than 50 ppm N (related to soil dry matter) had only a small effect on denitrification velocity in four of the five soils. In a clay soil dependence on nitrate concentration corresponded to a first-order reaction. Available C was no limiting factor. Even at zero temperatures remarkable N amounts (on average 0.2 ppm N per day) were still denitrified. The addition of daily turnover rates in relation to soil temperatures prevailing from December to March revealed potential turnovers in the 0-to-30-cm layer of the soils to average 28 ± 5 ppm N. (author)

  1. Surface geothermal exploration in the Canary Islands by means of soil CO_{2} degassing surveys

    García-Merino, Marta; Rodríguez, Fátima; Padrón, Eleazar; Melián, Gladys; Asensio-Ramos, María; Barrancos, José; Hernández, Pedro A.; Pérez, Nemesio M.

    2017-04-01

    With the exception of the Teide fumaroles, there is not any evidence of hydrothermal fluid discharges in the surficial environment of the Canary Islands, the only Spanish territory with potential high enthalpy geothermal resources. Here we show the results of several diffuse CO2 degassing surveys carried out at five mining licenses in Tenerife and Gran Canaria with the aim of sorting the possible geothermal potential of these five mining licenses. The primary objective of the study was to reduce the uncertainty inherent to the selection of the areas with highest geothermal potential for future exploration works. The yardstick used to classify the different areas was the contribution of volcano-hydrothermal CO2 in the diffuse CO2 degassing at each study area. Several hundreds of measurements of diffuse CO2 emission, soil CO2 concentration and isotopic composition were performed at each mining license. Based in three different endmembers (biogenic, atmospheric and deep-seated CO2) with different CO2 concentrations (100, 0.04 and 100%, respectively) and isotopic compositions (-24, -8 and -3 per mil vs. VPDB respectively) a mass balance to distinguish the different contribution of each endmember in the soil CO2 at each sampling site was made. The percentage of the volcano-hydrothermal contribution in the current diffuse CO2 degassing was in the range 0-19%. The Abeque mining license, that comprises part of the north-west volcanic rift of Tenerife, seemed to show the highest geothermal potential, with an average of 19% of CO2 being released from deep sources, followed by Atidama (south east of Gran Canaria) and Garehagua (southern volcanic rift of Tenerife), with 17% and 12% respectively.

  2. Residual effects of metal contamination on the soil quality: a field survey in central Portugal

    Kikuchi, Ryunosuke; Gerardo, Romeu

    2017-04-01

    Agriculture is an important source of income and employment. But depletion and degradation of land challenge to producing safe food and other agricultural products to sustain livelihoods and meet the needs of urban populations. When developing or expanding an agricultural area, it becomes essential to access the soil quality. Even if the present source of contamination is not observed, it is a worth subject to evaluate whether or not any negative effects of the post contamination still last. For this purpose, a field survey (2 ha) was carried: a zinc and lead mining site that was abandoned about 50 years ago was researched at Sanguinheiro (40°18'N and 8°21'W) in Central Portugal. The area is characterized by very steep slopes that are confining with a small stream. The obtained results show that (i) the Pb content in the site (165 mg/kg) is higher than that in the background (67.7 mg/kg); (ii) the Zn content of local vegetation (Eucalyptus globulus) in the post-mining site is 2.1 times that in the control site, and (iii) dead bare ground is observed in some parts of the site. There is a possibility that great amounts of Zn and Pb accumulate in tissues of local vegetation. Although mining activity ended 50 years ago, the contents of Pb and Zn in the sampled soil were comparatively high in the site with about a 75% slope. It is concluded that not only the present contamination but also the post-environmental stress should be assessed to properly develop an agricultural area in terms of securing agricultural products.

  3. Nitrogen supply modulates the effect of changes in drying-rewetting frequency on soil C and N cycling and greenhouse gas exchange.

    Morillas, Lourdes; Durán, Jorge; Rodríguez, Alexandra; Roales, Javier; Gallardo, Antonio; Lovett, Gary M; Groffman, Peter M

    2015-10-01

    Climate change and atmospheric nitrogen (N) deposition are two of the most important global change drivers. However, the interactions of these drivers have not been well studied. We aimed to assess how the combined effect of soil N additions and more frequent soil drying-rewetting events affects carbon (C) and N cycling, soil:atmosphere greenhouse gas (GHG) exchange, and functional microbial diversity. We manipulated the frequency of soil drying-rewetting events in soils from ambient and N-treated plots in a temperate forest and calculated the Orwin & Wardle Resistance index to compare the response of the different treatments. Increases in drying-rewetting cycles led to reductions in soil NO3- levels, potential net nitrification rate, and soil : atmosphere GHG exchange, and increases in NH4+ and total soil inorganic N levels. N-treated soils were more resistant to changes in the frequency of drying-rewetting cycles, and this resistance was stronger for C- than for N-related variables. Both the long-term N addition and the drying-rewetting treatment altered the functionality of the soil microbial population and its functional diversity. Our results suggest that increasing the frequency of drying-rewetting cycles can affect the ability of soil to cycle C and N and soil : atmosphere GHG exchange and that the response to this increase is modulated by soil N enrichment. © 2015 John Wiley & Sons Ltd.

  4. Error in measuring radon in soil gas by means of passive detectors

    Tanner, A.B.

    1991-01-01

    Passive detection of radon isotopes depends on diffusion of radon atoms from the sites of their generation to the location of the detecting or collecting device. Because some radon decays en route to a passive detector in soil, the radon concentration measured by the detector must be less than the concentration in those soil pores where it is undiminished by diffusion to the detector cavity. The true radon concentration may be significantly underestimated in moist soils. (author)

  5. The SAMI Galaxy Survey: a new method to estimate molecular gas surface densities from star formation rates

    Federrath, Christoph; Salim, Diane M.; Medling, Anne M.; Davies, Rebecca L.; Yuan, Tiantian; Bian, Fuyan; Groves, Brent A.; Ho, I.-Ting; Sharp, Robert; Kewley, Lisa J.; Sweet, Sarah M.; Richards, Samuel N.; Bryant, Julia J.; Brough, Sarah; Croom, Scott; Scott, Nicholas; Lawrence, Jon; Konstantopoulos, Iraklis; Goodwin, Michael

    2017-07-01

    Stars form in cold molecular clouds. However, molecular gas is difficult to observe because the most abundant molecule (H2) lacks a permanent dipole moment. Rotational transitions of CO are often used as a tracer of H2, but CO is much less abundant and the conversion from CO intensity to H2 mass is often highly uncertain. Here we present a new method for estimating the column density of cold molecular gasgas) using optical spectroscopy. We utilize the spatially resolved Hα maps of flux and velocity dispersion from the Sydney-AAO Multi-object Integral field spectrograph (SAMI) Galaxy Survey. We derive maps of Σgas by inverting the multi-freefall star formation relation, which connects the star formation rate surface density (ΣSFR) with Σgas and the turbulent Mach number (M). Based on the measured range of ΣSFR = 0.005-1.5 {M_{⊙} yr^{-1} kpc^{-2}} and M=18-130, we predict Σgas = 7-200 {M_{⊙} pc^{-2}} in the star-forming regions of our sample of 260 SAMI galaxies. These values are close to previously measured Σgas obtained directly with unresolved CO observations of similar galaxies at low redshift. We classify each galaxy in our sample as 'star-forming' (219) or 'composite/AGN/shock' (41), and find that in 'composite/AGN/shock' galaxies the average ΣSFR, M and Σgas are enhanced by factors of 2.0, 1.6 and 1.3, respectively, compared to star-forming galaxies. We compare our predictions of Σgas with those obtained by inverting the Kennicutt-Schmidt relation and find that our new method is a factor of 2 more accurate in predicting Σgas, with an average deviation of 32 per cent from the actual Σgas.

  6. Short-term effects of CO2 leakage on the soil bacterial community in a simulated gas leakage scenario

    Jing Ma

    2017-11-01

    Full Text Available The technology of carbon dioxide (CO2 capture and storage (CCS has provided a new option for mitigating global anthropogenic emissions with unique advantages. However, the potential risk of gas leakage from CO2 sequestration and utilization processes has attracted considerable attention. Moreover, leakage might threaten soil ecosystems and thus cannot be ignored. In this study, a simulation experiment of leakage from CO2 geological storage was designed to investigate the short-term effects of different CO2 leakage concentration (from 400 g m−2 day−1 to 2,000 g m−2 day−1 on soil bacterial communities. A shunt device and adjustable flow meter were used to control the amount of CO2 injected into the soil. Comparisons were made between soil physicochemical properties, soil enzyme activities, and microbial community diversity before and after injecting different CO2 concentrations. Increasing CO2 concentration decreased the soil pH, and the largest variation ranged from 8.15 to 7.29 (p < 0.05. Nitrate nitrogen content varied from 1.01 to 4.03 mg/Kg, while Olsen-phosphorus and total phosphorus demonstrated less regular downtrends. The fluorescein diacetate (FDA hydrolytic enzyme activity was inhibited by the increasing CO2 flux, with the average content varying from 22.69 to 11.25 mg/(Kg h (p < 0.05. However, the increasing activity amplitude of the polyphenol oxidase enzyme approached 230%, while the urease activity presented a similar rising trend. Alpha diversity results showed that the Shannon index decreased from 7.66 ± 0.13 to 5.23 ± 0.35 as the soil CO2 concentration increased. The dominant phylum in the soil samples was Proteobacteria, whose proportion rose rapidly from 28.85% to 67.93%. In addition, the proportion of Acidobacteria decreased from 19.64% to 9.29% (p < 0.01. Moreover, the abundances of genera Methylophilus, Methylobacillus, and Methylovorus increased, while GP4, GP6 and GP7 decreased. Canonical correlation analysis

  7. Effects of vegetation structure on soil carbon, nutrients and greenhouse gas exchange in a savannah ecosystem of Mount Kilimanjaro Region

    Becker, J.

    2015-12-01

    The savannah biome is a hotspot for biodiversity and wildlife conservation in Africa and recently got in the focus of research on carbon sequestration. Savannah ecosystems are under strong pressure from climate and land-use change, especially around populous areas like the Mt. Kilimanjaro region. Savannah vegetation consists of grassland with isolated trees and is therefore characterized by high spatial variation of canopy cover, aboveground biomass and root structure. The canopy structure is a major regulator for soil ecological parameters and soil-atmospheric trace gas exchange (CO2, N2O, CH4) in water limited environments. The spatial distribution of these parameters and the connection between above and belowground processes are important to understand and predict ecosystem changes and estimate its vulnerability. Our objective was to determine spatial trends and changes of soil parameters and relate their variability to the vegetation structure. We chose three trees from each of the two most dominant species (Acacia nilotica and Balanites aegyptiaca) in our research area. For each tree, we selected transects with nine sampling points of the same relative distances to the stem. At these each sampling point a soil core was taken and separated in 0-10 cm and 10-30 cm depth. We measured soil carbon (C) and nitrogen (N) storage, microbial biomass C and N, Natural δ13C, soil respiration, available nutrients, pH, cation exchange capacity (CEC) as well as root biomass and -density, soil temperature and soil water content. Concentrations and stocks of C and N fractions, CEC and K+ decreased up to 50% outside the crown covered area. Microbial C:N ratio and CO2 efflux was about 30% higher outside the crown. This indicates N limitation and low C use efficiency in soil outside the crown area. We conclude that the spatial structure of aboveground biomass in savanna ecosystems leads to a spatial variance in nutrient limitation. Therefore, the capability of a savanna ecosystem

  8. Soil gas (222Rn, CO2, 4He) behaviour over a natural CO2 accumulation, Montmiral area (Drome, France): geographical, geological and temporal relationships

    Gal, Frederick; Joublin, Franck; Haas, Hubert; Jean-prost, Veronique; Ruffier, Veronique

    2011-01-01

    The south east basin of France shelters deep CO 2 reservoirs often studied with the aim of better constraining geological CO 2 storage operations. Here we present new soil gas data, completing an existing dataset (CO 2 , 222 Rn, 4 He), together with mineralogical and physical characterisations of soil columns, in an attempt to better understand the spatial distribution of gas concentrations in the soils and to rule on the sealed character of the CO 2 reservoir at present time. Anomalous gas concentrations were found but did not appear to be clearly related to geological structures that may drain deep gases up to the surface, implying a dominant influence of near surface processes as indicated by carbon isotope ratios. Coarse grained, quartz-rich soils favoured the existence of high CO 2 concentrations. Fine grained clayey soils preferentially favoured the existence of 222 Rn but not CO 2 . Soil formations did not act as barriers preventing gas migrations in soils, either due to water content or due to mineralogical composition. No abundant leakage from the Montmiral reservoir can be highlighted by the measurements, even near the exploitation well. As good correlation between CO 2 and 222 Rn concentrations still exist, it is suggested that 222 Rn migration is also CO 2 dependent in non-leaking areas - diffusion dominated systems.

  9. Bioenergy by-products as soil amendments? Implications for carbon sequestration and greenhuise gas emissions

    Cayuela, M.L.; Oenema, O.; Kuikman, P.J.; Bakker, R.R.; Groenigen, van J.W.

    2010-01-01

    An important but little understood aspect of bioenergy production is its overall impact on soil carbon (C) and nitrogen (N) cycling. Increased energy production from biomass will inevitably lead to higher input of its by-products to the soil as amendments or fertilizers. However, it is still unclear

  10. Survey on Cooled-Vessel Designs in High Temperature Gas-Cooled Reactors

    Kim, Min-Hwan; Lee, Won-Jae

    2006-01-01

    The core outlet temperature of the coolant in the high temperature gas-cooled reactors (HTGR) has been increased to improve the overall efficiency of their electricity generation by using the Brayton cycle or their nuclear hydrogen production by using thermo-chemical processes. The increase of the outlet temperature accompanies an increase of the coolant inlet temperature. A high coolant inlet temperature results in an increase of the reactor pressure vessel (RPV) operation temperature. The conventional steels, proven vessel material in light water reactors, cannot be used as materials for the RPV in the elevated temperatures which necessitate its design to account for the creep effects. Some ferritic or martensitic steels like 2 1/4Cr-1Mo and 9Cr-1Mo-V are very well established creep resistant materials for a temperature range of 400 to 550 C. Although these materials have been used in a chemical plant, there is limited experience with using these materials in nuclear reactors. Even though the 2 1/4Cr-1Mo steel was used to manufacture the RPV for HTR-10 of Japan Atomic Energy Agency(JAEA), a large RPV has not been manufactured by using this material or 9Cr-1Mo-V steel. Due to not only its difficulties in manufacturing but also its high cost, the JAEA determined that they would exclude these materials from the GTHTR design. For the above reasons, KAERI has been considering a cooled-vessel design as an option for the RPV design of a NHDD plant (Nuclear Hydrogen Development and Demonstration). In this study, we surveyed several HTGRs, which adopt the cooled-vessel concept for their RPV design, and discussed their design characteristics. The survey results in design considerations for the NHDD cooled-vessel design

  11. Assessment of Hyporheic Zone, Flood-Plain, Soil-Gas, Soil, and Surface-Water Contamination at the McCoys Creek Chemical Training Area, Fort Gordon, Georgia, 2009-2010

    Guimaraes, Wladmir B.; Falls, W. Fred; Caldwell, Andral W.; Ratliff, W. Hagan; Wellborn, John B.; Landmeyer, James E.

    2011-01-01

    The U.S. Geological Survey, in cooperation with the U.S. Department of the Army Environmental and Natural Resources Management Office of the U.S. Army Signal Center and Fort Gordon, Georgia, assessed the hyporheic zone, flood plain, soil gas, soil, and surface water for contaminants at the McCoys Creek Chemical Training Area (MCTA) at Fort Gordon, from October 2009 to September 2010. The assessment included the detection of organic contaminants in the hyporheic zone, flood plain, soil gas, and surface water. In addition, the organic contaminant assessment included the analysis of organic compounds classified as explosives and chemical agents in selected areas. Inorganic contaminants were assessed in soil and surface-water samples. The assessment was conducted to provide environmental contamination data to the U.S. Army at Fort Gordon pursuant to requirements of the Resource Conservation and Recovery Act Part B Hazardous Waste Permit process. Ten passive samplers were deployed in the hyporheic zone and flood plain, and total petroleum hydrocarbons (TPH) and octane were detected above the method detection level in every sampler. Other organic compounds detected above the method detection level in the hyporheic zone and flood-plain samplers were trichloroethylene, and cis- and trans- 1, 2-dichloroethylene. One trip blank detected TPH below the method detection level but above the nondetection level. The concentrations of TPH in the samplers were many times greater than the concentrations detected in the blank; therefore, all other TPH concentrations detected are considered to represent environmental conditions. Seventy-one soil-gas samplers were deployed in a grid pattern across the MCTA. Three trip blanks and three method blanks were used and not deployed, and TPH was detected above the method detection level in two trip blanks and one method blank. Detection of TPH was observed at all 71 samplers, but because TPH was detected in the trip and method blanks, TPH was

  12. Fluid geochemistry and soil gas fluxes (CO2-CH4-H2S) at a promissory Hot Dry Rock Geothermal System: The Acoculco caldera, Mexico

    Peiffer, L.; Bernard-Romero, R.; Mazot, A.; Taran, Y. A.; Guevara, M.; Santoyo, E.

    2014-09-01

    The Acoculco caldera has been recognized by the Mexican Federal Electricity Company (CFE) as a Hot Dry Rock Geothermal System (HDR) and could be a potential candidate for developing an Enhanced Geothermal System (EGS). Apart from hydrothermally altered rocks, geothermal manifestations within the Acoculco caldera are scarce. Close to ambient temperature bubbling springs and soil degassing are reported inside the caldera while a few springs discharge warm water on the periphery of the caldera. In this study, we infer the origin of fluids and we characterize for the first time the soil degassing dynamic. Chemical and isotopic (δ18O-δD) analyses of spring waters indicate a meteoric origin and the dissolution of CO2 and H2S gases, while gas chemical and isotopic compositions (N2/He, 3He/4He, 13C, 15N) reveal a magmatic contribution with both MORB- and arc-type signatures which could be explained by an extension regime created by local and regional fault systems. Gas geothermometry results are in agreement with temperature measured during well drilling (260 °C-300 °C). Absence of well-developed water reservoir at depth impedes re-equilibration of gases upon surface. A multi-gas flux survey including CO2, CH4 and H2S measurements was performed within the caldera. Using the graphical statistical analysis (GSA) approach, CO2 flux measurements were classified in two populations. Population A, representing 95% of measured fluxes is characterized by low values (mean: 18 g m- 2 day- 1) while the remaining 5% fluxes belonging to Population B are much higher (mean: 5543 g m- 2 day- 1). This low degassing rate probably reflects the low permeability of the system, a consequence of the intense hydrothermal alteration observed in the upper 800 m of volcanic rocks. An attempt to interpret the origin and transport mechanism of these fluxes is proposed by means of flux ratios as well as by numerical modeling. Measurements with CO2/CH4 and CO2/H2S flux ratios similar to mass ratios

  13. Soils

    Freudenschuss, A.; Huber, S.; Riss, A.; Schwarz, S.; Tulipan, M.

    2001-01-01

    For Austria there exists a comprehensive soil data collection, integrated in a GIS (geographical information system). The content values of pollutants (cadmium, mercury, lead, copper, mercury, radio-cesium) are given in geographical charts and in tables by regions and by type of soil (forests, agriculture, greenland, others) for the whole area of Austria. Erosion effects are studied for the Austrian region. Legal regulations and measures for an effective soil protection, reduction of soil degradation and sustainable development in Austria and the European Union are discussed. (a.n.)

  14. [Interactions of straw, nitrogen fertilizer and bacterivorous nematodes on soil labile carbon and nitrogen and greenhouse gas emissions].

    Zhang, Teng-Hao; Wang, Nan; Liu, Man-Qiang; Li, Fang-Hui; Zhu, Kang-Li; Li, Hui-Xin; Hu, Feng

    2014-11-01

    A 3 x 2 factorial design of microcosm experiment was conducted to investigate the interactive effects of straw, nitrogen fertilizer and bacterivorous nematodes on soil microbial biomass carbon (C(mic)) and nitrogen (N(mic)), dissolved organic carbon (DOC) and nitrogen (DON), mineral nitrogen (NH(4+)-N and NO(3-)-N), and greenhouse gas (CO2, N2O and CH4) emissions. Results showed that straw amendment remarkably increased the numbers of bacterivorous nematodes and the contents of Cmic and Nmic, but Cmic and Nmic decreased with the increasing dose of nitrogen fertilization. The effects of bacterivorous nematodes strongly depended on either straw or nitrogen fertilization. The interactions of straw, nitrogen fertilization and bacterivorous nematodes on soil DOC, DON and mineral nitrogen were strong. Straw and nitrogen fertilization increased DOC and mineral nitrogen contents, but their influences on DON depended on the bacterivorous nematodes. The DOC and mineral nitrogen were negatively and positively influenced by the bacterivorous nematodes, re- spectively. Straw significantly promoted CO2 and N2O emissions but inhibited CH4 emission, while interactions between nematodes and nitrogen fertilization on emissions of greenhouse gases were obvious. In the presence of straw, nematodes increased cumulative CO2 emissions with low nitrogen fertilization, but decreased CO2 and N2O emissions with high nitrogen fertilization on the 56th day after incubation. In summary, mechanical understanding the soil ecological process would inevitably needs to consider the roles of soil microfauna.

  15. Greenhouse gas emissions from a Cu-contaminated soil remediated by in situ stabilization and phytomanaged by a mixed stand of poplar, willows, and false indigo-bush.

    Šimek, M; Elhottová, D; Mench, M; Giagnoni, L; Nannipieri, P; Renella, G

    2017-11-02

    Phytomanagement of trace element-contaminated soils can reduce soil toxicity and restore soil ecological functions, including the soil gas exchange with the atmosphere. We studied the emission rate of the greenhouse gases (GHGs) CO 2 , CH 4 , and N 2 O; the potential CH 4 oxidation; denitrification enzyme activity (DEA), and glucose mineralization of a Cu-contaminated soil amended with dolomitic limestone and compost, alone or in combination, after a 2-year phytomanagement with a mixed stand of Populus nigra, Salix viminalis, S. caprea, and Amorpha fruticosa. Soil microbial biomass and microbial community composition after analysis of the phospholipid fatty acids (PLFA) profile were determined. Phytomanagement significantly reduced Cu availability and soil toxicity, increased soil microbial biomass and glucose mineralization capacity, changed the composition of soil microbial communities, and increased the CO 2 and N 2 O emission rates and DEA. Despite such increases, microbial communities were evolving toward less GHG emission per unit of microbial biomass than in untreated soils. Overall, the aided phytostabilization option would allow methanotrophic populations to establish in the remediated soils due to decreased soil toxicity and increased nutrient availability.

  16. Advanced cost-effective surface geochemical techniques for oil/gas/uranium exploration, environmental assessments and pipeline monitoring - a template for India

    Lafleur, Paul; Chanrasekharan, G.Y.V.N.; Rajender Rao, S.

    2011-01-01

    Advanced geochemical soil gas methods have been successfully developed for the exploration of oil/gas/uranium and for environmental assessments. Application of these cost-effective technologies in India can substantially reduce exploration risk while accelerating the development of oil/gas/uranium onshore resources. A reliable and effective monitoring system using geochemical soil gas surveys ensures that CO 2 Enhanced Oil Recovery operations as well as CO 2 sequestration projects are safe and acceptable for the disposal of CO 2 , Soil gas surveys along with other technologies can also be applied for monitoring of oil/gas pipelines for leakage, especially those that are old or pass through populated regions

  17. Radon gas monitoring survey for the determination of Radon Prone Areas in Lombardia

    Bartolo, D. de; Alberici, A.; Gallini, R.; Maggioni, T.; Mondini, A.; Zini, E. [A.R.P.A. della Lombardia, Milano (Italy); Arrigoni, S.; Cazzaniga, P.; Cugini, A.; Gallinari, G.; Olivieri, F.; Romanelli, M. [A.R.P.A. della Lombardia, Dipt. di Bergamo, Bergamo (Italy)

    2006-07-01

    Region Lombardia has carried out a radon gas monitoring survey on its territory to localize radon prone areas as by law 241/00 enacted. To plan the survey, the Lombardia territory has been divided into two different types according to the morphology as well as the presence of a substratum of rock. The area with hills and mountains has been investigated with more attention compared to the plain because we can assume higher variability in radon concentration distribution due to the geological and morphological characteristics. The territory subdivision was based on the standard grid.. of the techniregional cartography (8 x 5 km). To perform radon indoor concentration measurements about 3600 measuring points were selected. They are located at the ground floor of buildings with the characteristics to ensure the tests are representative and comparable. It has also been taken into account evaluations done with previous surveys in accordance with the defined specification of the sites. The measurements were carried out using C.R. 39 trace detector technique. The detectors were contained in closed plastic canisters and they were positioned in situ for one year and measured each semester. The detectors were chemically treated and the traces counted using the automated optical system installed at the Radiometric Laboratory of the A.R.P.A. Department in Bergamo. The instrument accuracy and precision were evaluated using data obtained with different methods: using detectors exposed to radon known concentrations, participating to an international intercomparison as well as exposing the detector in a national calibration centre. Due to the large amount of detectors involved, a particular attention was taken for the detector homogeneity response and for the optimization of the analysis parameters. For further investigating the reliability of the measurements, two detectors were used in parallel in 10% of the tests. The results show higher values in the areas of Bergamo, Brescia

  18. Ionized Gas Outflows from the MAGNUM Survey: NGC 1365 and NGC 4945

    Venturi, Giacomo; Marconi, Alessandro [Dipartimento di Fisica e Astronomia, Università degli Studi di Firenze, Sesto Fiorentino (Italy); Osservatorio Astrofisico di Arcetri (INAF), Firenze (Italy); Mingozzi, Matilde [Osservatorio Astrofisico di Arcetri (INAF), Firenze (Italy); Dipartimento di Fisica e Astronomia, Università di Bologna, Bologna (Italy); Carniani, Stefano [Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge (United Kingdom); Kavli Institute for Cosmology, University of Cambridge, Cambridge (United Kingdom); Cresci, Giovanni [Osservatorio Astrofisico di Arcetri (INAF), Firenze (Italy); Risaliti, Guido [Dipartimento di Fisica e Astronomia, Università degli Studi di Firenze, Sesto Fiorentino (Italy); Osservatorio Astrofisico di Arcetri (INAF), Firenze (Italy); Mannucci, Filippo, E-mail: gventuri@arcetri.astro.it [Osservatorio Astrofisico di Arcetri (INAF), Firenze (Italy)

    2017-11-24

    AGN feedback, acting through strong outflows accelerated in the nuclear region of AGN hosts, is invoked as a key ingredient for galaxy evolution by many models to explain the observed BH-galaxy scaling relations. Recently, some direct observational evidence of radiative mode feedback in action has been finally found in quasars at z >1.5. However, it is not possible to study outflows in quasars at those redshifts on small scales (≲100 pc), as spatial information is limited by angular resolution. This is instead feasible in nearby active galaxies, which are ideal laboratories to explore outflow structure and properties, as well as the effects of AGN on their host galaxies. In this proceeding we present preliminary results from the MAGNUM survey, which comprises nearby Seyfert galaxies observed with the integral field spectrograph VLT/MUSE. We focus on two sources, NGC 1365 and NGC 4945, that exhibit double conical outflows extending on distances >1 kpc. We disentangle the dominant contributions to ionization of the various gas components observed in the central ~5.3 kpc of NGC 1365. An attempt to infer outflow 3D structure in NGC 4945 is made via simple kinematic modeling, suggesting a hollow cone geometry.

  19. Ionized Gas Outflows from the MAGNUM Survey: NGC 1365 and NGC 4945

    Giacomo Venturi

    2017-11-01

    Full Text Available AGN feedback, acting through strong outflows accelerated in the nuclear region of AGN hosts, is invoked as a key ingredient for galaxy evolution by many models to explain the observed BH-galaxy scaling relations. Recently, some direct observational evidence of radiative mode feedback in action has been finally found in quasars at z >1.5. However, it is not possible to study outflows in quasars at those redshifts on small scales (≲100 pc, as spatial information is limited by angular resolution. This is instead feasible in nearby active galaxies, which are ideal laboratories to explore outflow structure and properties, as well as the effects of AGN on their host galaxies. In this proceeding we present preliminary results from the MAGNUM survey, which comprises nearby Seyfert galaxies observed with the integral field spectrograph VLT/MUSE. We focus on two sources, NGC 1365 and NGC 4945, that exhibit double conical outflows extending on distances >1 kpc. We disentangle the dominant contributions to ionization of the various gas components observed in the central ~5.3 kpc of NGC 1365. An attempt to infer outflow 3D structure in NGC 4945 is made via simple kinematic modeling, suggesting a hollow cone geometry.

  20. Survey of high-velocity molecular gas in the vicinity of Herbig-Haro objects. I

    Edwards, S.; Snell, R.L.

    1983-01-01

    A survey of high-velocity molecular gas toward 49 Herbig-Haro objects is presented. Observations of the 12 CO J = 1-0 transition obtained with the 14 m telescope of the Five College Radio Astronomy Observatory reveal three new spatially extended high-velocity molecular outflows. One is in the NGC 1333 region near HH 12, and two are in the NGC 7129 region, the first near LkHα 234 and the second near a far-infrared source. The relationship between optical Herbin-Haro emission knots and large-scale motions of the ambient molecular material is investigated, and the properties of high-velocity molecular outflows in the vicinity of Herbig-Haro objects are discussed. Of 11 energetic outflows in the vicinity of Herbig-Haro objects, eight are found in four pairs separated by 0.2-1.0 pc. We estimate that energetic outflows characterized by mass loss rates > or =10 -7 M/sub sun/ yr -1 occur for at least 10 4 yr once in the lifetime of all stars with masses greater than 1M/sub sun/

  1. Gas

    1996-01-01

    The French government has decided to modify the conditions of extension of local natural gas authorities to neighbouring districts. The European Union is studying the conditions of internal gas market with the objective of more open markets although considering public service requirements

  2. Radon Gas Concentration Measurement In Soil For Some Holy Positions In Al-Najaf Al-Ashraf Governorate

    Hasan, K.H.; Hussain, H.H.

    2014-01-01

    In this search we measurement Radon gas concentration in the soil of holy positions in Al-Najaf Al-Ashraf city.We choice it for honorable position in all the world and, because millions of peoples and religious sciences students visit it.we selected 23 positions .By using a short-term way in modern technology its (RAD7) to measured concentration for depths (10,30,50,70)cm in all the holy positions.All the concentration in position studies within the range allowed of the global

  3. PO.RA project. An analysis on gas radon concentrations in soil versus fluctuations in the groundwater table

    Serentha', C.; Torretta, M.

    2001-01-01

    Man is daily exposed to natural radiation, mainly due to cosmic rays and natural radioactive elements, whose most important radioactive daughters are 222 Rn (radon) and 220 Rn (thoron). Being these ones gaseous, they can spread through the ground, reaching the atmosphere and accumulating in rooms, where their concentrations may be very high. As radon exhalation is strongly connected with the hydrogeological features of the environment, this study tried to find a relationship between fluctuations in the groundwater table and gas radon concentrations in soil, in order to try estimates of indoor radon concentrations [it

  4. Evaluation of the radionuclide concentrations in soil and plants from the 1975 terrestrial survey of Bikini and Eneu Islands

    Colsher, C.S.; Robison, W.L.; Gudiksen, P.H.

    1977-01-01

    In June 1975 a radiological survey was conducted of the terrestrial environment of Bikini and Eneu islands (Bikini Atoll) to evaluate the potential radiation dose to the returning Bikini population. In this report, we present measurements of the radionuclide concentration in soil profiles and in dominant species of edible and nonedible, indicator plants. The use of these data to derive relationships to predict the plant uptake of radionuclides from soil is described. Approximately 620 soil and vegetation samples from Bikini and Eneu Islands were analyzed by Ge(Li) gamma spectrometry and by wet chemistry. The predominant radionuclides in these samples were 60 Co, 90 Sr, 137 Cs, /sup 239,240/Pu, 241 Pu, and 241 Am

  5. Influence of Biochar on C and N Transformation in Soil and Their Impact on Greenhouse Gas Emissions

    Chintala, R.; Schumacher, T. E.; Kumar, S.; Clay, D. E.; Malo, D. D.

    2014-12-01

    (microbial biomass N, inorganic N, and δ 15N). Greenhouse gas fluxes (CO2, CH4, and N2O) were measured and correlation studies will be conducted to determine the relationship with the interference effect of biochars on C and N transformation in soil. Initial data shows that biochar has an impact especially on CO2, and N2O emissions.

  6. Soil Greenhouse Gas Fluxes in a Pacific Northwest Douglas-Fir Forest: Results from a Soil Fertilization and Biochar Addition Experiment

    Hawthorne, I.; Johnson, M. S.; Jassal, R. S.; Black, T. A.

    2013-12-01

    evacuated 12-mL vials and analyzed by gas chromatography. Chamber headspace GHG mixing ratios vs. time data were fit to linear and exponential models in R (Version 2.14.0) and fluxes were calculated. Results showed high variability in GHG fluxes over time in all treatments. Higher CO2 emissions were observed during early summer (119 μg CO2 m-2 s-1 in the control plots), decreasing with drought (19 μg CO2 m-2 s-1 in the control plots). CH4 uptake by soil increased during summer months from -0.004 μg CH4 m-2 s-1 to -0.089 μg CH4 m-2 s-1 in the control plots, in response to drying conditions in the upper soil profile. N2O was both consumed and emitted in all treatments, with fluxes ranging from -0.0009 to 0.0019 μg N2O m-2 s-1 in the control plots. Analysis of variance indicated that there were significant differences in GHG fluxes between treatments over time. We also investigated the potential effects of large volume headspace removal, and H2O vapour saturation leading to a dilution effect by using a closed-path infra-red gas analyzer with an inline humidity sensor.

  7. A survey of gas-side fouling in industrial heat-transfer equipment

    Marner, W. J.; Suitor, J. W.

    1983-11-01

    Gas-side fouling and corrosion problems occur in all of the energy intensive industries including the chemical, petroleum, primary metals, pulp and paper, glass, cement, foodstuffs, and textile industries. Topics of major interest include: (1) heat exchanger design procedures for gas-side fouling service; (2) gas-side fouling factors which are presently available; (3) startup and shutdown procedures used to minimize the effects of gas-side fouling; (4) gas-side fouling prevention, mitigation, and accommodation techniques; (5) economic impact of gas-side fouling on capital costs, maintenance costs, loss of production, and energy losses; and (6) miscellaneous considerations related to gas-side fouling. The present state-of-the-art for industrial gas-side fouling is summarized by a list of recommendations for further work in this area.

  8. The natural gas industry - a survey; Erdgaswirtschaft - Eine Branche im Ueberblick

    NONE

    2000-09-01

    The situation of natural gas in the Federal Republic of Germany is described, with particular emphasis on the advantages and consequences of natural gas supply. The brochure discusses the role of natural gas on the energy market, the reliability of natural gas supply, the environmental impacts, the energy-saving effect of natural gas, natural gas prices, the competitive strength of the German gas industry, and the long-term reliability of natural gas supply. (orig.) [German] Die Situation des Erdgases in der Bundesrepublik Deutschland wird beschrieben, wobei die wichtigsten Vorteile und Auswirkungen der Erdgasversorgung besonders hervorgehoben werden. Es geht um die Stellung des Erdgases im Energiemarkt, die Sicherheit der Energieversorgung, Umweltschutz, Energieeinsparung durch Erdgaseinsatz, Erdgaspreise, Leistungsfaehigkeit der deutschen Gaswirtschaft und um die langfristig gesicherte Erdgasversorgung. (orig.)

  9. Soil properties, greenhouse gas emissions and crop yield under compost, biochar and co-composted biochar in two tropical agronomic systems

    Bass, Adrian M., E-mail: adrian.bass@glasgow.ac.uk [Centre for Tropical Environmental and Sustainability Science, College of Science, Technology and Engineering, James Cook University, Cairns, Queensland 4870 (Australia); Bird, Michael I. [Centre for Tropical Environmental and Sustainability Science, College of Science, Technology and Engineering, James Cook University, Cairns, Queensland 4870 (Australia); Kay, Gavin [Terrain Natural Resource Management, 2 Stitt Street, Innisfail, Queensland 4860 (Australia); Muirhead, Brian [Northern Gulf Resource Management Group, 317 Byrnes Street, Mareeba, Queensland 4880 (Australia)

    2016-04-15

    ABSTRACT: The addition of organic amendments to agricultural soils has the potential to increase crop yields, reduce dependence on inorganic fertilizers and improve soil condition and resilience. We evaluated the effect of biochar (B), compost (C) and co-composted biochar (COMBI) on the soil properties, crop yield and greenhouse gas emissions from a banana and a papaya plantation in tropical Australia in the first harvest cycle. Biochar, compost and COMBI organic amendments improved soil properties, including significant increases in soil water content, CEC, K, Ca, NO{sub 3}, NH{sub 4} and soil carbon content. However, increases in soil nutrient content and improvements in physical properties did not translate to improved fruit yield. Counter to our expectations, banana crop yield (weight per bunch) was reduced by 18%, 12% and 24% by B, C and COMBI additions respectively, and no significant effect was observed on the papaya crop yield. Soil efflux of CO{sub 2} was elevated by addition of C and COMBI amendments, likely due to an increase in labile carbon for microbial processing. Our data indicate a reduction in N{sub 2}O flux in treatments containing biochar. The application of B, C and COMBI amendments had a generally positive effect on soil properties, but this did not translate into a crop productivity increase in this study. The benefits to soil nutrient content, soil carbon storage and N{sub 2}O emission reduction need to be carefully weighed against potentially deleterious effects on crop yield, at least in the short-term. - Highlights: • Biochar and compost amendment has potential to improve tropical agriculture. • We monitored soil health, gas fluxes and crop yield under biochar and compost. • Biochar improved soil nutrient content, water retention and reduced N{sub 2}O emissions. • Biochar significantly reduced banana yield performance and did not affect papaya yield. • Organic amendment is not an ‘always win’ scenario for tropical

  10. Soil properties, greenhouse gas emissions and crop yield under compost, biochar and co-composted biochar in two tropical agronomic systems

    Bass, Adrian M.; Bird, Michael I.; Kay, Gavin; Muirhead, Brian

    2016-01-01

    ABSTRACT: The addition of organic amendments to agricultural soils has the potential to increase crop yields, reduce dependence on inorganic fertilizers and improve soil condition and resilience. We evaluated the effect of biochar (B), compost (C) and co-composted biochar (COMBI) on the soil properties, crop yield and greenhouse gas emissions from a banana and a papaya plantation in tropical Australia in the first harvest cycle. Biochar, compost and COMBI organic amendments improved soil properties, including significant increases in soil water content, CEC, K, Ca, NO_3, NH_4 and soil carbon content. However, increases in soil nutrient content and improvements in physical properties did not translate to improved fruit yield. Counter to our expectations, banana crop yield (weight per bunch) was reduced by 18%, 12% and 24% by B, C and COMBI additions respectively, and no significant effect was observed on the papaya crop yield. Soil efflux of CO_2 was elevated by addition of C and COMBI amendments, likely due to an increase in labile carbon for microbial processing. Our data indicate a reduction in N_2O flux in treatments containing biochar. The application of B, C and COMBI amendments had a generally positive effect on soil properties, but this did not translate into a crop productivity increase in this study. The benefits to soil nutrient content, soil carbon storage and N_2O emission reduction need to be carefully weighed against potentially deleterious effects on crop yield, at least in the short-term. - Highlights: • Biochar and compost amendment has potential to improve tropical agriculture. • We monitored soil health, gas fluxes and crop yield under biochar and compost. • Biochar improved soil nutrient content, water retention and reduced N_2O emissions. • Biochar significantly reduced banana yield performance and did not affect papaya yield. • Organic amendment is not an ‘always win’ scenario for tropical agriculture.

  11. Emission Characteristics of Greenhouse Gas from Maize Field of Black Soil Region Under Long-term Fertilization

    GAO Hong-jun

    2017-08-01

    Full Text Available Study on greenhouse gases emission and their global warming potential under different fertilizations would be the theoretical basis for establishing measurements to reduce greenhouses gas emissions. Based on a long-term fertilization experiment, greenhouses gas(GHG emissions from black soil of summer maize were measured by using a static chamber-gas chromatograph technique, and global warming potential(GWP effect was also estimated. The results showed the peaks of CO2 and N2O emissions occurred at maize jointing period. The CO2 and N2O emission flux and CH4 uptake flux in the M2NPK treatment(mixed application of organic fertilizer and chemical fertilizer were significantly higher than those of the chemical fertilizer treatments(P2 and N2O emission flux in the chemical fertilizer treatments were higher than that of the no fertilizer treatment. The CO2 emission flux of the fallow treatment was the highest among all the treatments, but its N2O emission flux was significantly lower than that of the chemical fertilizer treatment. Under equal N rates, the N2O emission flux of the NPK treatment was significantly higher than that of the SNPK treatment(straw returning, but CH4 uptake flux was the opposite result. Compared with no fertilizer treatment(CK, GWP of the N and NPK treatments increased by 142% and 32% respectively, GWP of SNPK treatment decreased by 38%, and GWP in the M2NPK treatment was negative value. Greenhouse gas emission intensity(GHGI of the NPK, SNPK and M2NPK treatments were significantly lower than that of the CK and the N treatments, GHGI of the M2NPK treatment was -222 kg CO2-eq·t-1. Therefore, in order to implement the higher maize yield with lower GHGI synchronously, mixed application of organic fertilizer and chemical fertilizer would be the optimal fertilization measurement in black soil region of Northeast China.

  12. Epidemiological surveys of, and research on, soil-transmitted helminths in Southeast Asia: a systematic review.

    Dunn, Julia C; Turner, Hugo C; Tun, Aung; Anderson, Roy M

    2016-01-27

    Soil-transmitted helminth (STH) infections of humans fall within the World Health Organization's (WHO) grouping termed the neglected tropical diseases (NTDs). It is estimated that they affect approximately 1.4 billion people worldwide. A significant proportion of these infections are in the population of Southeast Asia. This review analyses published data on STH prevalence and intensity in Southeast Asia over the time period of 1900 to the present to describe age related patterns in these epidemiological measures. This is with a focus on the four major parasite species affecting humans; namely Ascaris lumbricoides, Trichuris trichiura and the hookworms; Necator americanus and Ancylostoma duodenale. Data were also collected on the diagnostic methods used in the published surveys and how the studies were designed to facilitate comparative analyses of re