WorldWideScience

Sample records for crop rotation systems

  1. The Energy Effectiveness Of Crops In Crop Rotation Under Different Soil Tillage Systems

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    Strašil Zdeněk

    2015-09-01

    Full Text Available The paper identifies and compares the energy balance of winter wheat, spring barley and white mustard – all grown in crop rotation under different tillage conditions. The field trial included the conventional tillage (CT method, minimum tillage (MT and a system with no tillage (NT. The energy inputs included both the direct and indirect energy component. Energy outputs are evaluated as gross calorific value (gross heating value of phytomass dry matter of the primary product and the total harvested production. The energy effectiveness (energy output: energy input was selected for evaluation. The greatest energy effectiveness for the primary product was established as 6.35 for barley, 6.04 for wheat and 3.68 for mustard; in the case of total production, it was 9.82 for barley, 10.08 for wheat and 9.72 for mustard. When comparing the different tillage conditions, the greatest energy effectiveness was calculated for the evaluated crops under the MT operation and represented the primary product of wheat at 6.49, barley at 6.69 and mustard at 3.92. The smallest energy effectiveness for the primary product was found in wheat 5.77 and barley 6.10 under the CT option; it was 3.55 for mustard under the option of NT. Throughout the entire cropping pattern, the greatest energy effectiveness was established under the minimum tillage option – 5.70 for the primary product and 10.47 for the total production. On the other hand, the smallest values were calculated under CT – 5.22 for the primary product and 9.71 for total production.

  2. Diversity of segetal weeds in pea (Pisum sativum L. depending on crops chosen for a crop rotation system

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    Marta K. Kostrzewska

    2014-04-01

    Full Text Available This study, lasting from 1999 to 2006, was conducted at the Research Station in Tomaszkowo, which belongs to the University of Warmia and Mazury in Olsztyn. The experiment was set up on brown rusty soil classified as good rye complex 5 in the Polish soil valuation system. The analysis comprised weeds in fields sown with pea cultivated in two four-field crop rotation systems with a different first crop: A. potato – spring barley – pea – spring barley; B. mixture of spring barley with pea – spring barley – pea – spring barley. Every year, at the 2–3 true leaf stage of pea, the species composition and density of individual weed species were determined; in addition, before harvesting the main crop, the dry matter of weeds was weighed. The results were used to analyze the constancy of weed taxa, species diversity, and the evenness and dominance indices, to determine the relationships between all biological indicators analyzed and weather conditions, and to calculate the indices of similarity, in terms of species composition, density and biomass of weeds, between the crop rotations compared. The species richness, density and biomass of weeds in fields with field pea were not differentiated by the choice of the initial crop in a given rotation system. In the spring, the total number of identified taxa was 28 and it increased to 36 before the harvest of pea plants. Chenopodium album and Echinochloa crus-galli were the most numerous. Chenopodium album, Echinochloa crus-galli, Sonchus arvensis, Fallopia convolvulus and Viola arvensis were constant in all treatments, regardless of what the first crop in rotation was or when the observations were made. The species diversity and the evenness and species dominance indices varied significantly between years and dates of observations. Species diversity calculated on the basis of the density of weed species was higher in the rotation with a mixture of cereals and legumes, while that calculated on

  3. Impact of Wheat/Faba Bean Mixed Cropping or Rotation Systems on Soil Microbial Functionalities

    Science.gov (United States)

    Wahbi, Sanâa; Prin, Yves; Thioulouse, Jean; Sanguin, Hervé; Baudoin, Ezékiel; Maghraoui, Tasnime; Oufdou, Khalid; Le Roux, Christine; Galiana, Antoine; Hafidi, Mohamed; Duponnois, Robin

    2016-01-01

    Cropping systems based on carefully designed species mixtures reveal many potential advantages in terms of enhancing crop productivity, reducing pest and diseases, and enhancing ecological services. Associating cereals and legume production either through intercropping or rotations might be a relevant strategy of producing both type of culture, while benefiting from combined nitrogen fixed by the legume through its symbiotic association with nitrogen-fixing bacteria, and from a better use of P and water through mycorrhizal associations. These practices also participate to the diversification of agricultural productions, enabling to secure the regularity of income returns across the seasonal and climatic uncertainties. In this context, we designed a field experiment aiming to estimate the 2 years impact of these practices on wheat yield and on soil microbial activities as estimated through Substrate Induced Respiration method and mycorrhizal soil infectivity (MSI) measurement. It is expected that understanding soil microbial functionalities in response to these agricultural practices might allows to target the best type of combination, in regard to crop productivity. We found that the tested cropping systems largely impacted soil microbial functionalities and MSI. Intercropping gave better results in terms of crop productivity than the rotation practice after two cropping seasons. Benefits resulting from intercrop should be highly linked with changes recorded on soil microbial functionalities. PMID:27695462

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

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    Bu, Rongyan; Lu, Jianwei; Ren, Tao; Liu, Bo; Li, Xiaokun; Cong, Rihuan

    2015-01-01

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

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

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    Rongyan Bu

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

  6. Analysis of methane yields from energy crops and agricultural by-products and estimation of energy potential from sustainable crop rotation systems in EU-27

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, Alexander; Leonhartsberger, Christian; Amon, Barbara; Amon, Thomas [University of Natural Resources and Applied Life Sciences, Division of Agricultural Engineering, Vienna (Austria); Boesch, Peter; Friedl, Anton [Vienna University of Technology, Vienna (Austria)

    2010-04-15

    Currently an increasing demand for renewable energy can be observed. A part of this demand could be covered by the production of energy from agrarian biomass. Due to the limited availability of arable land, food and feed production are starting to compete for agrarian resources. A way out of this dilemma is to develop concepts that are based on otherwise unused agrarian biomass like straw and include new technologies for the fermentation of lignocellulosic biomass. In this paper, the energy potentials of two different cropping systems are compared. In the energy-based crop rotation system all crops were used either for biogas or ethanol production. In the biorefinery-based approach, the various crops were used in cascades for the production of food as well as feed. Experimental laboratory work and field trials were combined to calculate energy and biomass yields of the crops under investigation. The results demonstrate that steam explosion pretreatment of wheat straw led to a 30% increase in the specific methane yield. The calculated energy output of the biorefinery-based crop rotation system amounted to a total of 126 GJ ha{sup -1} year{sup -1}. Extrapolating this energy output to the total arable land of the EU-27 member states, 13,608 PJ of energy could be produced. Therefore, biorefinery-based crop rotation systems could provide approximately three times more energy to the European population than energy-based crop rotation systems. (orig.)

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

    OpenAIRE

    FRANCHINI, J. C.; Crispino, C.C.; de Souza, R. A.; Torres, E; HUNGRIA, M.

    2007-01-01

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

  8. Energy crops in rotation. A review

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    Zegada-Lizarazu, Walter; Monti, Andrea [Department of Agroenvironmental Science and Technology, University of Bologna, Viale G. Fanin, 44 - 40127, Bologna (Italy)

    2011-01-15

    The area under energy crops has increased tenfold over the last 10 years, and there is large consensus that the demand for energy crops will further increase rapidly to cover several millions of hectares in the near future. Information about rotational systems and effects of energy crops should be therefore given top priority. Literature is poor and fragmentary on this topic, especially about rotations in which all crops are exclusively dedicated to energy end uses. Well-planned crop rotations, as compared to continuous monoculture systems, can be expected to reduce the dependence on external inputs through promoting nutrient cycling efficiency, effective use of natural resources, especially water, maintenance of the long-term productivity of the land, control of diseases and pests, and consequently increasing crop yields and sustainability of production systems. The result of all these advantages is widely known as crop sequencing effect, which is due to the additional and positive consequences on soil physical-chemical and biological properties arising from specific crops grown in the same field year after year. In this context, the present review discusses the potential of several rotations with energy crops and their possibilities of being included alongside traditional agriculture systems across different agro-climatic zones within the European Union. Possible rotations dedicated exclusively to the production of biomass for bioenergy are also discussed, as rotations including only energy crops could become common around bio-refineries or power plants. Such rotations, however, show some limitations related to the control of diseases and to the narrow range of available species with high production potential that could be included in a rotation of such characteristics. The information on best-known energy crops such as rapeseed (Brassica napus) and sunflower (Helianthus annuus) suggests that conventional crops can benefit from the introduction of energy crops in

  9. Carbon stock and its compartments in a subtropical oxisol under long-term tillage and crop rotation systems

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    Ben-Hur Costa de Campos

    2011-06-01

    Full Text Available Soil organic matter (SOM plays a crucial role in soil quality and can act as an atmospheric C-CO2 sink under conservationist management systems. This study aimed to evaluate the long-term effects (19 years of tillage (CT-conventional tillage and NT-no tillage and crop rotations (R0-monoculture system, R1-winter crop rotation, and R2- intensive crop rotation on total, particulate and mineral-associated organic carbon (C stocks of an originally degraded Red Oxisol in Cruz Alta, RS, Southern Brazil. The climate is humid subtropical Cfa 2a (Köppen classification, the mean annual precipitation 1,774 mm and mean annual temperature 19.2 ºC. The plots were divided into four segments, of which each was sampled in the layers 0-0.05, 0.05-0.10, 0.10-0.20, and 0.20-0.30 m. Sampling was performed manually by opening small trenches. The SOM pools were determined by physical fractionation. Soil C stocks had a linear relationship with annual crop C inputs, regardless of the tillage systems. Thus, soil disturbance had a minor effect on SOM turnover. In the 0-0.30 m layer, soil C sequestration ranged from 0 to 0.51 Mg ha-1 yr-1, using the CT R0 treatment as base-line; crop rotation systems had more influence on soil stock C than tillage systems. The mean C sequestration rate of the cropping systems was 0.13 Mg ha-1 yr-1 higher in NT than CT. This result was associated to the higher C input by crops due to the improvement in soil quality under long-term no-tillage. The particulate C fraction was a sensitive indicator of soil management quality, while mineral-associated organic C was the main pool of atmospheric C fixed in this clayey Oxisol. The C retention in this stable SOM fraction accounts for 81 and 89 % of total C sequestration in the treatments NT R1 and NT R2, respectively, in relation to the same cropping systems under CT. The highest C management index was observed in NT R2, confirming the capacity of this soil management practice to improve the soil C

  10. [Effects of different multiple cropping systems on paddy field weed community under long term paddy-upland rotation].

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    Yang, Bin-Juan; Huang, Guo-Qin; Xu, Ning; Wang, Shu-Bin

    2013-09-01

    Based on a long term field experiment, this paper studied the effects of different multiple cropping systems on the weed community composition and species diversity under paddy-upland rotation. The multiple cropping rotation systems could significantly decrease weed density and inhibited weed growth. Among the rotation systems, the milk vetch-early rice-late maize --> milk vetchearly maize intercropped with early soybean-late rice (CCSR) had the lowest weed species dominance, which inhibited the dominant weeds and decreased their damage. Under different multiple cropping systems, the main weed community was all composed of Monochoia vaginalis, Echinochloa crusgalli, and Sagittaria pygmae, and the similarity of weed community was higher, with the highest similarity appeared in milk vetch-early rice-late maize intercropped with late soybean --> milk vetch-early maize-late rice (CSCR) and in CCSR. In sum, the multiple cropping rotations in paddy field could inhibit weeds to a certain extent, but attentions should be paid to the damage of some less important weeds.

  11. TOTAL CARBON STOCK IN AGRICULTURAL SYSTEM HAVING CROP ROTATION IN TARAI REGION OF NORTHERN INDIA

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    Kavita Tariyal

    2014-06-01

    Full Text Available Soil organic carbon pools are important in maintaining soil productivity and influencing the CO2 loading into the atmosphere. Agricultural soils can mitigate the problem of carbon concentration increase in atmosphere if proper management practices are involved. In the present study, total carbon stock in crops and soil was analyzed for two years along with crop rotation practice to observe its impact on the carbon pool. For that two agricultural fields C12 and D7 were incorporated with different crop rotations for two years and on the basis of this SOC, Total Carbon, soil respiration and carbon stock were measured. In the end of the study C12 showed higher biomass carbon stock (2.61 t ha-1 as compared to D7 (1.98 t ha-1 and also higher total carbon stock (plant+soil (40.09 t ha-1 as compared to D7 (38.30 t ha-1. Results prove that agriculture can not only be the source but also an effective sink if it is properly managed with different crop rotation practices and also with no-till practice.

  12. Long-term C-CO2 emissions and carbon crop residue mineralization in an oxisol under different tillage and crop rotation systems

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    Ben-Hur Costa de Campos

    2011-06-01

    Full Text Available Soil C-CO2 emissions are sensitive indicators of management system impacts on soil organic matter (SOM. The main soil C-CO2 sources at the soil-plant interface are the decomposition of crop residues, SOM turnover, and respiration of roots and soil biota. The objectives of this study were to evaluate the impacts of tillage and cropping systems on long-term soil C-CO2 emissions and their relationship with carbon (C mineralization of crop residues. A long-term experiment was conducted in a Red Oxisol in Cruz Alta, RS, Brazil, with subtropical climate Cfa (Köppen classification, mean annual precipitation of 1,774 mm and mean annual temperature of 19.2 ºC. Treatments consisted of two tillage systems: (a conventional tillage (CT and (b no tillage (NT in combination with three cropping systems: (a R0- monoculture system (soybean/wheat, (b R1- winter crop rotation (soybean/wheat/soybean/black oat, and (c R2- intensive crop rotation (soybean/ black oat/soybean/black oat + common vetch/maize/oilseed radish/wheat. The soil C-CO2 efflux was measured every 14 days for two years (48 measurements, by trapping the CO2 in an alkaline solution. The soil gravimetric moisture in the 0-0.05 m layer was determined concomitantly with the C-CO2 efflux measurements. The crop residue C mineralization was evaluated with the mesh-bag method, with sampling 14, 28, 56, 84, 112, and 140 days after the beginning of the evaluation period for C measurements. Four C conservation indexes were used to assess the relation between C-CO2 efflux and soil C stock and its compartments. The crop residue C mineralization fit an exponential model in time. For black oat, wheat and maize residues, C mineralization was higher in CT than NT, while for soybean it was similar. Soil moisture was higher in NT than CT, mainly in the second year of evaluation. There was no difference in tillage systems for annual average C-CO2 emissions, but in some individual evaluations, differences between

  13. Regional variability of environmental effects of energy crop rotations

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    Prescher, Anne-Katrin; Peter, Christiane; Specka, Xenia; Willms, Matthias; Glemnitz, Michael

    2014-05-01

    The use of energy crops for bioenergy production is increasingly promoted by different frameworks and policies (ECCP, UNFCCC). Energy cropping decreases greenhouse gas emissions by replacing the use of fossil fuel. However, despite this, growing in monocultures energy crop rotations has low environmental benefit. It is broadly accepted consensus that sustainable energy cropping is only realizable by crop rotations which include several energy crop species. Four crop rotations consisting of species mixtures of C3, C4 and leguminous plants and their crop positions were tested to identify the environmental effect of energy cropping systems. The experimental design included four replicates per crop rotation each covering four cultivation years. The study took place at five sites across Germany covering a considerable range of soil types (loamy sand to silt loam), temperatures (7.5 ° C - 10.0 ° C) and precipitation (559 mm - 807 mm) which allow a regional comparison of crop rotation performance. Four indicators were used to characterize the environmental conditions: (1) greenhouse gas (GHG) emissions from the management actions; (2) change in humus carbon (Chum); (3) groundwater recharge (RGW) and (4) nitrogen dynamics. The indicators were derived by balance, by an empirical model and by a dynamic model, respectively, all based and calibrated on measured values. The results show that the crop rotation impact on environmental indicators varied between plant species mixtures and the crop positions, between sites and climate. Crop rotations with 100 % energy crops (including C4 plants) had negative influence on Chum, GHG emissions per area and RGW in comparison to the rotation of 50 % energy crops and 50 % cash crops, which were mainly due to the remaining straw on the field. However, the biogas yield of the latter rotation was smaller, thus GHG emissions per product were higher, pointing out the importance to distinguish between GHG emissions per product and per area

  14. Short rotation Wood Crops Program

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    Wright, L.L.; Ehrenshaft, A.R.

    1990-08-01

    This report synthesizes the technical progress of research projects in the Short Rotation Woody Crops Program for the year ending September 30, 1989. The primary goal of this research program, sponsored by the US Department of Energy's Biofuels and Municipal Waste Technology Division, is the development of a viable technology for producing renewable feedstocks for conversion to biofuels. One of the more significant accomplishments was the documentation that short-rotation woody crops total delivered costs could be $40/Mg or less under optimistic but attainable conditions. By taking advantage of federal subsidies such as those offered under the Conservation Reserve Program, wood energy feedstock costs could be lower. Genetic improvement studies are broadening species performance within geographic regions and under less-than-optimum site conditions. Advances in physiological research are identifying key characteristics of species productivity and response to nutrient applications. Recent developments utilizing biotechnology have achieved success in cell and tissue culture, somaclonal variation, and gene-insertion studies. Productivity gains have been realized with advanced cultural studies of spacing, coppice, and mixed-species trials. 8 figs., 20 tabs.

  15. Crop rotation modelling - A European model intercomparison

    DEFF Research Database (Denmark)

    Kollas, Chris; Kersebaum, Kurt C; Nendel, Claas;

    2015-01-01

    Diversification of crop rotations is considered an option to increase the resilience of European crop production under climate change. So far, however, many crop simulation studies have focused on predicting single crops in separate one-year simulations. Here, we compared the capability of fiftee...

  16. Colonisation of winter wheat grain by Fusarium spp. and mycotoxin content as dependent on a wheat variety, crop rotation, a crop management system and weather conditions.

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    Czaban, Janusz; Wróblewska, Barbara; Sułek, Alicja; Mikos, Marzena; Boguszewska, Edyta; Podolska, Grażyna; Nieróbca, Anna

    2015-01-01

    Field experiments were conducted during three consecutive growing seasons (2007/08, 2008/09 and 2009/10) with four winter wheat (Triticum aestivum L.) cultivars - 'Bogatka', 'Kris', 'Satyna' and 'Tonacja' - grown on fields with a three-field crop rotation (winter triticale, spring barley, winter wheat) and in a four-field crop rotation experiment (spring wheat, spring cereals, winter rapeseed, winter wheat). After the harvest, kernels were surface disinfected with 2% NaOCl and then analysed for the internal infection by different species of Fusarium. Fusaria were isolated on Czapek-Dox iprodione dichloran agar medium and identified on the basis of macro- and micro-morphology on potato dextrose agar and synthetic nutrient agar media. The total wheat grain infection by Fusarium depended mainly on relative humidity (RH) and a rainfall during the flowering stage. Intensive rainfall and high RH in 2009 and 2010 in the period meant the proportions of infected kernels by the fungi were much higher than those in 2008 (lack of precipitation during anthesis). Weather conditions during the post-anthesis period changed the species composition of Fusarium communities internally colonising winter wheat grain. The cultivars significantly varied in the proportion of infected kernels by Fusarium spp. The growing season and type of crop rotation had a distinct effect on species composition of Fusarium communities colonising the grain inside. A trend of a higher percentage of the colonised kernels by the fungi in the grain from the systems using more fertilisers and pesticides as well as the buried straw could be perceived. The most frequent species in the grain were F. avenaceum, F. tricinctum and F. poae in 2008, and F. avenaceum, F. graminearum, F. tricinctum and F. poae in 2009 and 2010. The contents of deoxynivalenol and zearalenon in the grain were correlated with the percentage of kernels colonised by F. graminearum and were the highest in 2009 in the grain from the four

  17. Development and Deployment of a Short Rotation Woody Crops Harvesting System Based on a Case New Holland Forage Harvester and SRC Woody Crop Header

    Energy Technology Data Exchange (ETDEWEB)

    Eisenbies, Mark [State Univ. of New York College of Environmental Science and Forestry (SUNY-ESF), Syracuse, NY (United States); Volk, Timothy [State Univ. of New York College of Environmental Science and Forestry (SUNY-ESF), Syracuse, NY (United States); Abrahamson, Lawrence [State Univ. of New York College of Environmental Science and Forestry (SUNY-ESF), Syracuse, NY (United States); Shuren, Richard [GreenWood Resources, Inc., Portland, OR (United States); Stanton, Brian [GreenWood Resources, Inc., Portland, OR (United States); Posselius, John [Case New Holland, New Holland, PA (United States); McArdle, Matt [Mesa Reduction Engineering and Processing, Inc., Auburn, NY (United States); Karapetyan, Samvel [State Univ. of New York College of Environmental Science and Forestry (SUNY-ESF), Syracuse, NY (United States); Patel, Aayushi [State Univ. of New York College of Environmental Science and Forestry (SUNY-ESF), Syracuse, NY (United States); Shi, Shun [State Univ. of New York College of Environmental Science and Forestry (SUNY-ESF), Syracuse, NY (United States); Zerpa, Jose [State Univ. of New York College of Environmental Science and Forestry (SUNY-ESF), Syracuse, NY (United States)

    2014-10-03

    Biomass for biofuels, bioproducts and bioenergy can be sourced from forests, agricultural crops, various residue streams, and dedicated woody or herbaceous crops. Short rotation woody crops (SRWC), like willow and hybrid poplar, are perennial cropping systems that produce a number of environmental and economic development benefits in addition to being a renewable source of biomass that can be produced on marginal land. Both hybrid poplar and willow have several characteristics that make them an ideal feedstock for biofuels, bioproducts, and bioenergy; these include high yields that can be obtained in three to four years, ease of cultivar propagation from dormant cuttings, a broad underutilized genetic base, ease of breeding, ability to resprout after multiple harvests, and feedstock composition similar to other sources of woody biomass. Despite the range of benefits associated with SRWC systems, their deployment has been restricted by high costs, low market acceptance associated with inconsistent chip quality (see below for further explanation), and misperceptions about other feedstock characteristics (see below for further explanation). Harvesting of SRWC is the largest single cost factor (~1/3 of the final delivered cost) in the feedstock supply system. Harvesting is also the second largest input of primary fossil energy in the system after commercial N fertilizer, accounting for about one third of the input. Therefore, improving the efficiency of the harvesting system has the potential to reduce both cost and environmental impact. At the start of this project, we projected that improving the overall efficiency of the harvesting system by 25% would reduce the delivered cost of SRWC by approximately $0.50/MMBtu (or about $7.50/dry ton). This goal was exceeded over the duration of this project, as noted below.

  18. Carbon stocks quantification in agricultural systems employing succession and rotation of crops in Rio Grande do Sul State, Brazil.

    Science.gov (United States)

    Walter, Michele K. C.; Marinho, Mara de A.; Denardin, José E.; Zullo, Jurandir, Jr.; Paz-González, Antonio

    2013-04-01

    Soil and vegetation constitute respectively the third and the fourth terrestrial reservoirs of Carbon (C) on Earth. C sequestration in these reservoirs includes the capture of the CO2 from the atmosphere by photosynthesis and its storage as organic C. Consequently, changes in land use and agricultural practices affect directly the emissions of the greenhouse gases and the C sequestration. Several studies have already demonstrated that conservation agriculture, and particularly zero tillage (ZT), has a positive effect on soil C sequestration. The Brazilian federal program ABC (Agriculture of Low Carbon Emission) was conceived to promote agricultural production with environmental protection and represents an instrument to achieve voluntary targets to mitigate emissions or NAMAS (National Appropriated Mitigation Actions). With financial resources of about US 1.0 billion until 2020 the ABC Program has a target of expand ZT in 8 million hectares of land, with reduction of 16 to 20 million of CO2eq. Our objective was to quantify the C stocks in soil, plants and litter of representative grain crops systems under ZT in Rio Grande do Sul State, Brazil. Two treatments of a long term experimental essay (> 20 years) were evaluated: 1) Crop succession with wheat (Triticum aestivum L.)/soybean (Glycine max (L.) Merril); 2) Crop rotation with wheat/soybean (1st year), vetch (Vicia sativa L.)/soybean (2nd year), and white oat (Avena sativa L.)/sorghum (Sorghum bicolor L.) (3rd year). C quantification in plants and in litter was performed using the direct method of biomass quantification. The soil type evaluated was a Humic Rhodic Hapludox, and C quantification was executed employing the method referred by "C mass by unit area". Results showed that soybean plants under crop succession presented greater C stock (4.31MgC ha-1) comparing with soybean plants cultivated under crop rotation (3.59 MgC ha-1). For wheat, however, greater C stock was quantified in plants under rotation

  19. Development and Deployment of a Short Rotation Woody Crops Harvesting System Based on a Case New Holland Forage Harvester and SRC Woody Crop Header

    Energy Technology Data Exchange (ETDEWEB)

    Eisenbies, Mark [SUNY ESF; Volk, Timothy [SUNY ESF

    2014-10-03

    Demand for bioenergy sourced from woody biomass is projected to increase; however, the expansion and rapid deployment of short rotation woody crop systems in the United States has been constrained by high production costs and sluggish market acceptance due to problems with quality and consistency from first-generation harvesting systems. The objective of this study was to evaluate the effect of crop conditions on the performance of a single-pass, cut and chip harvester based on a standard New Holland FR-9000 series forage harvester with a dedicated 130FB short rotation coppice header, and the quality of chipped material. A time motion analysis was conducted to track the movement of machine and chipped material through the system for 153 separate loads over 10 days on a 54-ha harvest. Harvester performance was regulated by either ground conditions, or standing biomass on 153 loads. Material capacities increased linearly with standing biomass up to 40 Mgwet ha-1 and plateaued between 70 and 90 Mgwet hr-1. Moisture contents ranged from 39 to 51% with the majority of samples between 43 and 45%. Loads produced in freezing weather (average temperature over 10 hours preceding load production) had 4% more chips greater than 25.4 mm (P < 0.0119). Over 1.5 Mgdry ha-1 of potentially harvested material (6-9% of a load) was left on site, of which half was commercially undesirable meristematic pieces. The New Holland harvesting system is a reliable and predictable platform for harvesting material over a wide range of standing biomass; performance was consistent overall in 14 willow cultivars.

  20. The Effect of Tillage System and Crop Rotation on Soil Microbial Diversity and Composition in a Subtropical Acrisol

    Directory of Open Access Journals (Sweden)

    Eric W. Triplett

    2012-10-01

    Full Text Available Agricultural management alters physical and chemical soil properties, which directly affects microbial life strategies and community composition. The microbial community drives important nutrient cycling processes that can influence soil quality, cropping productivity and environmental sustainability. In this research, a long-term agricultural experiment in a subtropical Acrisol was studied in south Brazil. The plots at this site represent two tillage systems, two nitrogen fertilization regimes and three crop rotation systems. Using Illumina high-throughput sequencing of the 16S rRNA gene, the archaeal and bacterial composition was determined from phylum to species level in the different plot treatments. The relative abundance of these taxes was correlated with measured soil properties. The P, Mg, total organic carbon, total N and mineral N were significantly higher in the no-tillage system. The microbial diversity was higher in the no-tillage system at order, family, genus and species level. In addition, overall microbial composition changed significantly between conventional tillage and no-tillage systems. Anaerobic bacteria, such as clostridia, dominate in no-tilled soil as well as anaerobic methanogenic archaea, which were detected only in the no-tillage system. Microbial diversity was higher in plots in which only cereals (oat and maize were grown. Soil management influenced soil biodiversity on Acrisol by change of composition and abundance of individual species.

  1. Impacts of crop rotations on soil organic carbon sequestration

    Science.gov (United States)

    Gobin, Anne; Vos, Johan; Joris, Ingeborg; Van De Vreken, Philippe

    2013-04-01

    Agricultural land use and crop rotations can greatly affect the amount of carbon sequestered in the soil. We developed a framework for modelling the impacts of crop rotations on soil carbon sequestration at the field scale with test case Flanders. A crop rotation geo-database was constructed covering 10 years of crop rotation in Flanders using the IACS parcel registration (Integrated Administration and Control System) to elicit the most common crop rotation on major soil types in Flanders. In order to simulate the impact of crop cover on carbon sequestration, the Roth-C model was adapted to Flanders' environment and coupled to common crop rotations extracted from the IACS geodatabases and statistical databases on crop yield. Crop allometric models were used to calculate crop residues from common crops in Flanders and subsequently derive stable organic matter fluxes to the soil (REGSOM). The REGSOM model was coupled to Roth-C model was run for 30 years and for all combinations of seven main arable crops, two common catch crops and two common dosages of organic manure. The common crops are winter wheat, winter barley, sugar beet, potato, grain maize, silage maize and winter rapeseed; the catch crops are yellow mustard and Italian ryegrass; the manure dosages are 35 ton/ha cattle slurry and 22 ton/ha pig slurry. Four common soils were simulated: sand, loam, sandy loam and clay. In total more than 2.4 million simulations were made with monthly output of carbon content for 30 years. Results demonstrate that crop cover dynamics influence carbon sequestration for a very large percentage. For the same rotations carbon sequestration is highest on clay soils and lowest on sandy soils. Crop residues of grain maize and winter wheat followed by catch crops contribute largely to the total carbon sequestered. This implies that agricultural policies that impact on agricultural land management influence soil carbon sequestration for a large percentage. The framework is therefore

  2. Response of soil microbial biomass and community structures to conventional and organic farming systems under identical crop rotations.

    Science.gov (United States)

    Esperschütz, Jürgen; Gattinger, Andreas; Mäder, Paul; Schloter, Michael; Fliessbach, Andreas

    2007-07-01

    In this study the influence of different farming systems on microbial community structure was analyzed using soil samples from the DOK long-term field experiment in Switzerland, which comprises organic (BIODYN and BIOORG) and conventional (CONFYM and CONMIN) farming systems as well as an unfertilized control (NOFERT). We examined microbial communities in winter wheat plots at two different points in the crop rotation (after potatoes and after maize). Employing extended polar lipid analysis up to 244 different phospholipid fatty acids (PLFA) and phospholipid ether lipids (PLEL) were detected. Higher concentrations of PLFA and PLEL in BIODYN and BIOORG indicated a significant influence of organic agriculture on microbial biomass. Farmyard manure (FYM) application consistently revealed the strongest, and the preceding crop the weakest, influence on domain-specific biomass, diversity indices and microbial community structures. Esterlinked PLFA from slowly growing bacteria (k-strategists) showed the strongest responses to long-term organic fertilization. Although the highest fungal biomass was found in the two organic systems of the DOK field trial, their contribution to the differentiation of community structures according to the management regime was relatively low. Prokaryotic communities responded most strongly to either conventional or organic farming management.

  3. Diversifying cereal-based rotations to improve weed control. Evaluation with the AlomySys model quantifying the effect of cropping systems on a grass weed

    Directory of Open Access Journals (Sweden)

    Colbach Nathalie

    2010-09-01

    Full Text Available Simplified rotations often select weed flora consisting of one or several dominant species. In rotations consisting mainly of winter cereals, one of the most frequent weeds in Atlantic European countries is blackgrass (Alopecurus myosuroides Huds.. In order to reduce environmental impacts and avoid the selection of herbicide-resistant populations, alternative weed management strategies are necessary. The objective of the present study was to develop a methodology for using a weed dynamics model called ALOMYSYS for evaluating prospective diversified crop rotations based on expert opinion. These prospective rotations were developed for a particular region aiming at reducing herbicide use while keeping weed infestation similar to that in current cropping systems. The prospective systems were also evaluated economically by calculating costs and margins for the farmer. The simulations showed that the more diverse the rotation, the better blackgrass was controlled and the less herbicides (rates and frequencies were necessary. Optimal herbicide spraying conditions and mouldboard ploughing were also less essential in diverse rotations. It was though essential to reason herbicide programs over the whole rotation and not simply as function of the preceding crop. The economic evaluation identified the interest of spring or winter pea either replacing or preceding oilseed rape (OSR in OSR/wheat/barley rotations.

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

    Science.gov (United States)

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

    2010-05-01

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

  5. Yield and Economic Responses of Peanut to Crop Rotation Sequence

    Science.gov (United States)

    Proper crop rotation is essential to maintaining high peanut yield and quality. However, the economic considerations of maintaining or altering crop rotation sequences must incorporate the commodity prices, production costs, and yield responses of all crops in, or potentially in, the crop rotation ...

  6. Grain legumes in organic cropping systems

    OpenAIRE

    Hauggaard-Nielsen, Dr. Henrik

    2002-01-01

    Grain legumes are valuable protein and energy sources in animal feeds and in human diets low in meat. Furthermore, grain legumes strongly benefit the cropping system, via biological fixation of atmospheric N2 - a fundamental process for maintaining soil fertility in organic farming systems. Other positive effects in the crop rotations are recycled N-rich crop residues and the break-crop effect in cereals-rich rotations. However, yield variability in grain legumes is well known and related to...

  7. Three-year measurements of nitrous oxide emissions from cotton and wheat-maize rotational cropping systems

    Science.gov (United States)

    Liu, Chunyan; Yao, Zhisheng; Wang, Kai; Zheng, Xunhua

    2014-10-01

    The remarkable expansion of fertilization and irrigation may stimulate nitrous oxide (N2O) emissions from cropping systems in northern China. High-resolution measurements were conducted in irrigated cotton and wheat-maize rotational systems in Shanxi Province, P.R. China, between 2007 and 2010 (three year-round crop cycles, hereinafter referred to as Y1, Y2 and Y3) to investigate the impacts of natural inter-annual variations and agricultural management on annual N2O emissions and direct emission factors (EFs). Overall, N2O emissions fluctuated diurnally, seasonally and inter-annually in the fertilized treatments. The hourly N2O fluxes closely followed the daily air temperature patterns. The daily mean fluxes corresponded to these hourly fluxes, which were observed between 09:00-10:00 and 19:00-20:00. An optimized sampling protocol could improve the reliability of discrete measurements when estimating cumulative emissions. The N2O emissions for the fertilized treatments were 2.7 ± 0.2 (Y1) and 1.6 ± 0.1 kg N ha-1 yr-1 (Y2) from the cotton field and 6.2 ± 0.4 (Y1), 4.5 ± 0.3 (Y2) and 4.5 ± 0.2 kg N ha-1 yr-1 (Y3) from the wheat-maize field. Peak N2O emissions after fertilization and irrigation/rainfall lasted one to three weeks and accounted for 16-55% of the annual emissions. Leaching losses were estimated at 10.4 ± 3.0 (Y1) and 12.5 ± 3.4 kg N ha-1 yr-1 (Y2), which accounted for 16-17% of the fertilizer-N applied to the cotton field. Annual N2O emissions did not increase with increasing fertilization rates or water inputs because significant amounts of fertilizer-N were lost through leaching. Background emissions amounted to one-third to one-half of the total N2O emissions from the fertilized treatments. The direct EFs were 2.2 ± 0.3% (Y1) and 0.9 ± 0.2% (Y2) in the cotton field and 1.3 ± 0.2% (Y1), 0.8 ± 0.1% (Y2) and 0.7 ± 0.1% (Y3) in the wheat-maize field. The large inter-annual variations in N2O emissions and direct EFs emphasize the importance of

  8. Impacts of projected climate change on productivity and nitrogen leaching of crop rotations in arable and pig farming systems in Denmark

    DEFF Research Database (Denmark)

    Doltra, Jordi; Lægdsmand, Mette; Olesen, Jørgen E

    2014-01-01

    The effects of projected changes in climate and atmospheric CO2 concentration on productivity and nitrogen (N) leaching of characteristic arable and pig farming rotations in Denmark were investigated with the FASSET simulation model. The LARS weather generator was used to provide climatic data...... in Denmark, differing in soil and climate, and representative of the selected production systems. The CO2 effects were modelled using projected CO2 concentrations for the A1B emission scenario. Crop rotations were irrigated (sandy soil) and unirrigated (sandy loam soil), and all included systems...... rather than single crops for impact assessments. Potato and sugar beet in arable farming and grain maize in pig farming contributed most to the productivity increase in the future scenarios. The highest productivity was obtained in the arable system on the sandy loam soil, with an increase of 20...

  9. Greenhouse Gas Emissions and Global Warming Potential of Traditional and Diversified Tropical Rice Rotation Systems including Impacts of Upland Crop Management Practices i.e. Mulching and Inter-crop Cultivation

    Science.gov (United States)

    Janz, Baldur; Weller, Sebastian; Kraus, David; Wassmann, Reiner; Butterbach-Bahl, Klaus; Kiese, Ralf

    2016-04-01

    Paddy rice cultivation is increasingly challenged by irrigation water scarcity, while at the same time changes in demand (e.g. changes in diets or increasing demand for biofuels) will feed back on agricultural practices. These factors are changing traditional cropping patterns from flooded double-rice systems to the introduction of well-aerated upland crop systems in the dry season. Emissions of methane (CH4) are expected to decrease, while emissions of nitrous oxide (N2O) will increase and soil organic carbon (SOC) stocks will most likely be volatilized in the form of carbon dioxide (CO2). We measured greenhouse gas (GHG) emissions at the International Rice Research Institute (IRRI) in the Philippines to provide a comparative assessment of the global warming potentials (GWP) as well as yield scaled GWPs of different crop rotations and to evaluate mitigation potentials or risks of new management practices i.e. mulching and inter-crop cultivation. New management practices of mulching and intercrop cultivation will also have the potential to change SOC dynamics, thus can play the key role in contributing to the GWP of upland cropping systems. To present, more than three years of continuous measurement data of CH4 and N2O emissions in double-rice cropping (R-R) and paddy rice rotations diversified with either maize (R-M) or aerobic rice (R-A) in upland cultivation have been collected. Introduction of upland crops in the dry season reduced irrigation water use and CH4 emissions by 66-81% and 95-99%, respectively. Moreover, for practices including upland crops, CH4 emissions in the subsequent wet season with paddy rice were reduced by 54-60%. Although annual N2O emissions increased twice- to threefold in the diversified systems, the strong reduction of CH4 led to a significantly lower (psystem. Measurements of soil organic carbon contents before and three years after introduction of upland crop rotations indicated a SOC loss for the R-M system, while for the other

  10. Carbon footprints of crops from organic and conventional arable crop rotations – using a life cycle assessment approach

    DEFF Research Database (Denmark)

    Knudsen, Marie Trydeman; Meyer-Aurich, A; Olesen, Jørgen E

    2014-01-01

    organic arable crop rotations with different sources of N supply. Data from long-term field experiments at three different locations in Denmark were used to analyse three different organic cropping systems (‘Slurry’, ‘Biogas’ and ‘Mulching’), one conventional cropping system (‘Conventional’) and a “No...... input” system as reference systems. The ‘Slurry’ and ‘Conventional’ rotations received slurry and mineral fertilizer, respectively, whereas the ‘No input’ was unfertilized. The ‘Mulching’ and ‘Biogas’ rotations had one year of grass-clover instead of a faba bean crop. The grass-clover biomass...... was incorporated in the soil in the ‘Mulching’ rotation and removed and used for biogas production in the ‘Biogas’ rotation (and residues from biogas production were simulated to be returned to the field). A method was suggested for allocating effects of fertility building crops in life cycle assessments...

  11. Rainfed intensive crop systems

    DEFF Research Database (Denmark)

    Olesen, Jørgen E

    2014-01-01

    This chapter focuses on the importance of intensive cropping systems in contributing to the world supply of food and feed. The impact of climate change on intensive crop production systems is also discussed....

  12. Effects of nitrogen and phosphorus fertilizer on crop yields in a field pea-spring wheat-potato rotation system with calcareous soil in semi-arid environments

    Energy Technology Data Exchange (ETDEWEB)

    Liu, C.A.; Zhang, S.; Hua, S.; Rao, X.

    2016-11-01

    The object of the present study was to investigate the yield-affecting mechanisms influenced by N and P applications in rainfed areas with calcareous soil. The experimental treatments were as follows: NF (no fertilizer), N (nitrogen), P (phosphorus), and NP (nitrogen plus phosphorus) in a field pea-spring wheat-potato cropping system. This study was conducted over six years (2003-2008) on China’s semi-arid Loess Plateau. The fertilizer treatments were found to decrease the soil water content more than the NF treatment in each of the growing seasons. The annual average yields of the field pea crops during the entire experimental period were 635, 677, 858, and 1117 kg/ha for the NF, N, P, and NP treatments, respectively. The annual average yields were 673, 547, 966, and 1056 kg/ha for the spring wheat crops for the NF, N, P, and NP treatments, respectively. Also, the annual average yields were 1476, 2120, 1480, and 2424 kg/ha for the potato crops for the NF, N, P, and NP treatments, respectively. In the second cycle of the three-year rotation, the pea and spring wheat yields in the P treatment were 1.2 and 2.8 times higher than that in the N treatment, respectively. Meanwhile, the potato crop yield in the N treatment was 3.1 times higher than that in the P treatment. In conclusion, the P fertilizer was found to increase the yields of the field pea and wheat crops, and the N fertilizer increased the potato crop yield in rainfed areas with calcareous soil. (Author)

  13. Evaluation of oilseed crop rotations with agro-environmental indicators

    Directory of Open Access Journals (Sweden)

    Pouzet André

    2003-05-01

    Full Text Available The European Common Agricultural Policy is shifting an increasing part of the subsidies to eco-conditionality. Henceforth, it becomes essential to evaluate the environmental effect of agricultural practices, and more generally performances of cropping and farming systems, in order to design and to develop more sustainable systems. This assessment is being implemented for the main cropping systems of some French regions, using environmental indicators. Eleven exposure indicators were chosen in order to represent a wide range of specific sustainability objectives dealing with water, soil, air, non-renewable resources, biodiversity, and landscape. The results present the sustainability assessment for the crop rotations of Champagne Berrichonne region in the Centre of France.

  14. Nitrogen Fertilizer Management for Enhancing Crop Productivity and Nitrogen Use Efficiency in a Rice-Oilseed Rape Rotation System in China

    Directory of Open Access Journals (Sweden)

    Muhammad Yousaf

    2016-09-01

    Full Text Available The use of efficient rates of nitrogen (N fertilizer application is important with regard to increasing crop productivity and maintaining environmental sustainability. Rice-oilseed rape rotations are a mainstay of the economy and food security of China. Therefore, a field experiment was carried out during 2011–2013 in Honghu to identify the most appropriate N application rates for enhancing crop productivity and N use efficiency for rice (Oryza sativa L.-oilseed rape (Brassica napus L. rotations. Six N fertilizer treatments (RO1, RO2, RO3, RO4, RO5, and RO6 were laid out in a randomized complete block design with three replicates. ROx represented the N fertilizer application rates (kg ha–1 for rice and oilseed rape, respectively. Grain yields from plots receiving N fertilizer were significantly increased by 59–71% (rice and 109–160% (oilseed rape during the total rotation (2011–2013, as compared to RO1 (control; no application. Furthermore, a similar trend was observed for N accumulation, ranging from 88–125% and 134–200% in aerial parts of rice and oilseed rape, respectively. Nitrogen use efficiency (NUE was significantly higher (38.5% under RO2 and lower (34.2% under RO6 while apparent N balance (ANB was positively lowest under R05 (183.4 kg ha–1 followed by R02 (234.2 kg ha–1 and highest under R06 (344.5 kg ha–1 during the total rotation. The results of grain yield, NUE, and ANB indicated that the R02 rate of N application was superior. This information should help to develop a cost-effective and environment-friendly N management strategy for rice-oilseed rape rotation systems of central China.

  15. Nitrogen Fertilizer Management for Enhancing Crop Productivity and Nitrogen Use Efficiency in a Rice-Oilseed Rape Rotation System in China

    Science.gov (United States)

    Yousaf, Muhammad; Li, Xiaokun; Zhang, Zhi; Ren, Tao; Cong, Rihuan; Ata-Ul-Karim, Syed Tahir; Fahad, Shah; Shah, Adnan N.; Lu, Jianwei

    2016-01-01

    The use of efficient rates of nitrogen (N) fertilizer application is important with regard to increasing crop productivity and maintaining environmental sustainability. Rice-oilseed rape rotations are a mainstay of the economy and food security of China. Therefore, a field experiment was carried out during 2011–2013 in Honghu to identify the most appropriate N application rates for enhancing crop productivity and N use efficiency for rice (Oryza sativa L.)-oilseed rape (Brassica napus L.) rotations. Six N fertilizer treatments (RO1, RO2, RO3, RO4, RO5, and RO6) were laid out in a randomized complete block design with three replicates. ROx represented the N fertilizer application rates (kg ha−1) for rice and oilseed rape, respectively. Grain yields from plots receiving N fertilizer were significantly increased by 59–71% (rice) and 109–160% (oilseed rape) during the total rotation (2011–2013), as compared to RO1 (control; no application). Furthermore, a similar trend was observed for N accumulation, ranging from 88 to 125% and 134 to 200% in aerial parts of rice and oilseed rape, respectively. Nitrogen use efficiency (NUE) was significantly higher (38.5%) under RO2 and lower (34.2%) under RO6 while apparent N balance (ANB) was positively lowest under R05 (183.4 kg ha−1) followed by R02 (234.2 kg ha−1) and highest under R06 (344.5 kg ha−1) during the total rotation. The results of grain yield, NUE, and ANB indicated that the R02 rate of N application was superior. This information should help to develop a cost-effective and environment-friendly N management strategy for rice-oilseed rape rotation systems of central China. PMID:27746809

  16. Tropical rotation crops influence nematode densities and vegetable yields.

    Science.gov (United States)

    McSorley, R; Dickson, D W; de Brito, J A; Hochmuth, R C

    1994-09-01

    The effects of eight summer rotation crops on nematode densities and yields of subsequent spring vegetable crops were determined in field studies conducted in north Florida from 1991 to 1993. The crop sequence was as follows: (i) rotation crops during summer 1991; (ii) cover crop of rye (Secale cereale) during winter 1991-92; (iii) 'Lemondrop L' squash (Cucurbita pepo) during spring 1992; (iv) rotation crops during summer 1992; (v) rye during winter 1992-93; (vi) 'Classic' eggplant (Solanum melongena) during spring 1993. The eight summer crop rotation treatments were as follows: 'Hale' castor (Ricinus communis), velvetbean (Mucuna deeringiana), sesame (Sesamum indicum), American jointvetch (Aeschynomene americana), weed fallow, 'SX- 17' sorghum-sudangrass (Sorghum bicolor x S. sudanense), 'Kirby' soybean (Glycine max), and 'Clemson Spineless' okra (Hibiscus esculentus) as a control. Rotations with castor, velvetbean, American jointvetch, and sorghum-sudangrass were most effective in maintaining the lowest population densities of Meloidogyne spp. (a mixture of M. incognita race 1 and M. arenaria race 1), but Paratrichodorus minor built up in the sorghum-sudangrass rotation. Yield of squash was lower (P crops evaluated here may be useful for managing nematodes in the field and for improving yields of subsequent vegetable crops.

  17. Nitrogen migration in crop rotations differing in fertilisation

    Energy Technology Data Exchange (ETDEWEB)

    Guzys, S.; Miseviciene, S.

    2015-07-01

    Inappropriate use of nitrogen fertilisers is becoming a global problem; however, continuous fertilisation with N fertiliser ensures large and constant harvests. To evaluate the relationships of differently fertilised cultivated plant rotation with N metabolism in the agroecosystem the research was conducted between 2006 and 2013 at Lipliūnai, Lithuania, in fields with calcareous gley brown soil, i.e. Endocalcari Endohypogleyic Cambisol (CMg-n-w-can). The research area covered three drained plots where crop rotation of differently fertilised cereals and perennial grasses were applied. The greatest productivity was found in a higher fertilisation (TII, 843 kg N/ha) cereals crop rotation. With less fertilisation (TI, 540 kg N/ha) crop rotation productivity of cereals and perennial grasses (TIII, 218 kg N/ha) was 11-35% lower. The highest amount of mineral soil N (average 76 kg/ha) was found in TI. It was influenced by fertilisation (r=0.71) and crop productivity (r=0.39). TIII tended to reduce Nmin (12.1 mg/L) and Ntotal (12.8 mg/L) concentrations in drainage water and leaching of these elements (7 and 8 kg/ha). Nmin and Ntotal concentrations in the water depended on crop productivity respectively (r=0.48; r=0.36), quantity of mineral soil N (r=0.65; r=0.59), fertilisation (r=0.59; r=0.52), and N balance (r=0.26; r=0.35). Cereal crop rotation increased N leaching by 12-42%. The use of all crop rotations resulted in a negative N balance. Nitrogen balance depended on fertilisation with N fertiliser (r=0.55). The application of perennial grasses crop rotation in agricultural fields was the best environmental tool, reducing N migration to drainage. (Author)

  18. Crop rotation biomass and arbuscular mycorrhizal fungi effects on sugarcane yield

    Energy Technology Data Exchange (ETDEWEB)

    Ambrosano, Edmilson Jose; Rossi, Fabricio; Guirado, Nivaldo; Teramoto, Juliana Rolim Salome [Agencia Paulista de Tecnologia dos Agronegocios (APTA), Piracicaba, SP (Brazil). Polo Regional Centro Sul; Azcon, Rozario [Consejo Superior de Investigaciones Cientificas (CSIC), Granada (Spain). Estacao Experimental de Zaidin; Cantarela, Heitor [Agencia Paulista de Tecnologia dos Agronegocios (APTA/IAC), Campinas, SP (Brazil). Inst. Agronomico. Centro de Solos e Recursos Ambientais; Ambrosano, Glaucia Maria Bovi [Universidade Estadual de Campinas (UNICAMP), Piracicaba, SP (Brazil). Fac. de Odontologia. Dept. de Odontologia Social], Email: ambrosano@apta.sp.gov.br; Schammass, Eliana Aparecida [Agencia Paulista de Tecnologia dos Agronegocios (APTA/IZ), Nova Odessa, SP (Brazil). Inst. de Zootecnia; Muraoka, Takashi; Trivelin, Paulo Cesar Ocheuze [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil); Ungaro, Maria Regina Goncalves [Agencia Paulista de Tecnologia dos Agronegocios (APTA/IAC), Campinas, SP (Brazil). Inst. Agronomico. Centro de Plantas Graniferas

    2010-07-01

    Sugarcane (Saccharum spp.) is an important crop for sugar production and agro-energy purposes in Brazil. In the sugarcane production system after a 4- to 8-year cycle crop rotation may be used before replanting sugarcane to improve soil conditions and give an extra income. This study had the objective of characterizing the biomass and the natural colonization of arbuscular mycorrhizal fungi (AMF) of leguminous green manure and sunflower (Helianthus annuus L.) in rotation with sugarcane. Their effect on stalk and sugar yield of sugarcane cv. IAC 87-3396 grown subsequently was also studied. Cane yield was harvested in three subsequent cuttings. Peanut cv. IAC-Caiapo, sunflower cv. IAC-Uruguai and velvet bean (Mucuna aterrimum Piper and Tracy) were the rotational crops that resulted in the greater percentage of AMF. Sunflower was the specie that most extracted nutrients from the soil, followed by peanut cv. IAC-Tatu and mung bean (Vigna radiata L. Wilczek). The colonization with AMF had a positive correlation with sugarcane plant height, at the first cut (p = 0.01 and R = 0.52) but not with the stalk or cane yields. Sunflower was the rotational crop that brought about the greatest yield increase of the subsequent sugarcane crop: 46% increase in stalk yield and 50% in sugar yield compared with the control. Except for both peanut varieties, all rotational crops caused an increase in net income of the cropping system in the average of three sugarcane harvests. (author)

  19. Influence of crop rotation and tillage intensity on soil physical properties and functions

    Science.gov (United States)

    Krümmelbein, Julia

    2013-04-01

    Soil tillage intensity can vary concerning tillage depth, frequency, power input into the soil and degree of soil turn-over. Conventional tillage systems where a plough is regularly used to turn over the soil can be differentiated from reduced tillage systems without ploughing but with loosening the upper soil and no tillage systems. Between conventional tillage and no tillage is a wide range of more or less reduced tillage systems. In our case the different tillage intensities are not induced by different agricultural machinery or techniques, but result from varying crop rotations with more or less perennial crops and therefore lower or higher tillage frequency. Our experimental area constitutes of quite unstructured substrates, partly heavily compacted. The development of a functioning soil structure and accumulation of nutrients and organic matter are of high importance. Three different crop rotations induce varying tillage intensities and frequencies. The first crop rotation (Alfalfa monoculture) has only experienced seed bed preparation once and subsequently is wheeled once a year to cut and chaff the biomass. The second crop rotation contains perennial and annual crops and has therefore been tilled more often, while the third crop rotation consists only of annual crops with annual seedbed preparation. Our results show that reduced tillage intensity/frequency combined with the intense root growth of Alfalfa creates the most favourable soil physical state of the substrate compared to increased tillage and lower root growth intensity of the other crop rotations. Soil tillage disturbs soil structure development, especially when the substrate is mechanically unstable as in our case. For such problematic locations it is recommendable to reduce tillage intensity and/or frequency to allow the development of soil structure enhanced by root growth and thereby the accumulation of organic matter and nutrients within the rooting zone.

  20. Soil microbial biomass and function are altered by 12 years of crop rotation

    Science.gov (United States)

    McDaniel, Marshall D.; Grandy, A. Stuart

    2016-11-01

    Declines in plant diversity will likely reduce soil microbial biomass, alter microbial functions, and threaten the provisioning of soil ecosystem services. We examined whether increasing temporal plant biodiversity in agroecosystems (by rotating crops) can partially reverse these trends and enhance soil microbial biomass and function. We quantified seasonal patterns in soil microbial biomass, respiration rates, extracellular enzyme activity, and catabolic potential three times over one growing season in a 12-year crop rotation study at the W. K. Kellogg Biological Station LTER. Rotation treatments varied from one to five crops in a 3-year rotation cycle, but all soils were sampled under a corn year. We hypothesized that crop diversity would increase microbial biomass, activity, and catabolic evenness (a measure of functional diversity). Inorganic N, the stoichiometry of microbial biomass and dissolved organic C and N varied seasonally, likely reflecting fluctuations in soil resources during the growing season. Soils from biodiverse cropping systems increased microbial biomass C by 28-112 % and N by 18-58 % compared to low-diversity systems. Rotations increased potential C mineralization by as much as 53 %, and potential N mineralization by 72 %, and both were related to substantially higher hydrolase and lower oxidase enzyme activities. The catabolic potential of the soil microbial community showed no, or slightly lower, catabolic evenness in more diverse rotations. However, the catabolic potential indicated that soil microbial communities were functionally distinct, and microbes from monoculture corn preferentially used simple substrates like carboxylic acids, relative to more diverse cropping systems. By isolating plant biodiversity from differences in fertilization and tillage, our study illustrates that crop biodiversity has overarching effects on soil microbial biomass and function that last throughout the growing season. In simplified agricultural systems

  1. Will breeding for nitrogen use efficient crops lead to nitrogen use efficient cropping systems?

    DEFF Research Database (Denmark)

    Dresbøll, Dorte Bodin; Thorup-Kristensen, Kristian

    2014-01-01

    The benefits of improving nitrogen use efficiency (NUE) in crops are typically studied through the performance of the individual crop. However, in order to increase yields in a sustainable way, improving NUE of the cropping systems must be the aim. We did a model simulation study to investigate how...... improvement of NUE traits of individual crops affects the succeeding crops and the NUE of the crop rotation. Based on experimental results parameterization was altered for different types of improved NUE in the EU-Rotate_N model, e.g. through higher N harvest index, reduced litter loss or improved root depth...... penetration rate. The different ways of improving NUE have different effects on the cropping system, affecting either N uptake, the ability of the crop to hold on to N already taken up, or the fraction of crop N being harvested. Due to the different modes of action, the model simulations show...

  2. Economics, energy, and environmental assessment of diversified crop rotations in sub-Himalayas of India.

    Science.gov (United States)

    Singh, Raman Jeet; Meena, Roshan Lal; Sharma, N K; Kumar, Suresh; Kumar, Kuldeep; Kumar, Dileep

    2016-02-01

    Reducing the carbon footprint and increasing energy use efficiency of crop rotations are the two most important sustainability issues of the modern agriculture. Present study was undertaken to assess economics, energy, and environmental parameters of common diversified crop rotations (maize-tomato, and maize-toria-wheat) vis-a-vis traditional crop rotations like maize-wheat, maize + ginger and rice-wheat of the north-western Himalayan region of India. Results revealed that maize-tomato and maize + ginger crop rotations being on par with each other produced significantly higher system productivity in terms of maize equivalent yield (30.2-36.2 t/ha) than other crop rotations (5.04-7.68 t/ha). But interestingly in terms of energy efficiencies, traditional maize-wheat system (energy efficiency 7.9, human energy profitability of 177.8 and energy profitability of 6.9 MJ/ha) was significantly superior over other systems. Maize + ginger rotation showed greater competitive advantage over other rotations because of less consumption of non-renewable energy resources. Similarly, maize-tomato rotation had ability of the production process to exploit natural resources due to 14-38% less use of commercial or purchased energy sources over other crop rotations. Vegetable-based crop rotations (maize + ginger and maize-tomato) maintained significantly the least carbon footprint (0.008 and 0.019 kg CO2 eq./kg grain, respectively) and the highest profitability (154,322 and 274,161 Rs./ha net return, respectively) over other crop rotations. As the greatest inputs of energy and carbon across the five crop rotations were nitrogen fertilizer (15-29% and 17-28%, respectively), diesel (14-24% and 8-19%, respectively) and irrigation (10-27% and 11-44%, respectively), therefore, alternative sources like organic farming, conservation agriculture practices, soil and water conservation measures, rain water harvesting etc. should be encouraged to reduce dependency of direct energy and external

  3. Biogas crops grown in energy crop rotations: Linking chemical composition and methane production characteristics.

    Science.gov (United States)

    Herrmann, Christiane; Idler, Christine; Heiermann, Monika

    2016-04-01

    Methane production characteristics and chemical composition of 405 silages from 43 different crop species were examined using uniform laboratory methods, with the aim to characterise a wide range of crop feedstocks from energy crop rotations and to identify main parameters that influence biomass quality for biogas production. Methane formation was analysed from chopped and over 90 days ensiled crop biomass in batch anaerobic digestion tests without further pre-treatment. Lignin content of crop biomass was found to be the most significant explanatory variable for specific methane yields while the methane content and methane production rates were mainly affected by the content of nitrogen-free extracts and neutral detergent fibre, respectively. The accumulation of butyric acid and alcohols during the ensiling process had significant impact on specific methane yields and methane contents of crop silages. It is proposed that products of silage fermentation should be considered when evaluating crop silages for biogas production.

  4. Environmental enhancement using short-rotation woody crops and perennial grasses as alternative agricultural crops

    Energy Technology Data Exchange (ETDEWEB)

    Tolbert, V.R. [Oak Ridge National Lab., TN (United States); Schiller, A. [Oak Ridge Inst. for Science and Education, TN (United States)

    1995-12-31

    Short-rotation woody crops and perennial grasses are grown as biomass feedstocks for energy and fiber. When replacing traditional row crops on similar lands, these alternative crops can provide multiple environmental benefits in addition to enhancing rural economies and providing valuable feedstock resources. The Department of Energy is supporting research to address how these crops can provide environmental benefits to soil, water and native wildlife species in addition to providing bioenergy feedstocks. Research is underway to address the potential for biomass crops to provide soil conservation and water quality improvements in crop settings. Replacement of traditional erosive row crops with biomass crops on marginal lands and establishment of biomass plantations as filter strips adjacent to streams and wetlands are being studied. The habitat value of different biomass crops for selected wildlife species is also under study. To date, these studies have shown that in comparison with row crops biomass plantings of both grass and tree crops increased biodiversity of birds; however, the habitat value of tree plantations is not equivalent to natural forests. The effects on native wildlife of establishing multiple plantations across a landscape are being studied. Combining findings on wildlife use of individual plantations with information on the cumulative effects of multiple plantations on wildlife populations can provide guidance for establishing and managing biomass crops to enhance biodiversity while providing biomass feedstocks. Data from site-specific environmental studies can provide input for evaluation of the probable effects of large-scale plantings at both landscape and regional levels of resolution.

  5. Crop rotational diversity enhances belowground communities and functions in an agroecosystem.

    Science.gov (United States)

    Tiemann, L K; Grandy, A S; Atkinson, E E; Marin-Spiotta, E; McDaniel, M D

    2015-08-01

    Biodiversity loss, an important consequence of agricultural intensification, can lead to reductions in agroecosystem functions and services. Increasing crop diversity through rotation may alleviate these negative consequences by restoring positive aboveground-belowground interactions. Positive impacts of aboveground biodiversity on belowground communities and processes have primarily been observed in natural systems. Here, we test for the effects of increased diversity in an agroecosystem, where plant diversity is increased over time through crop rotation. As crop diversity increased from one to five species, distinct soil microbial communities were related to increases in soil aggregation, organic carbon, total nitrogen, microbial activity and decreases in the carbon-to-nitrogen acquiring enzyme activity ratio. This study indicates positive biodiversity-function relationships in agroecosystems, driven by interactions between rotational and microbial diversity. By increasing the quantity, quality and chemical diversity of residues, high diversity rotations can sustain soil biological communities, with positive effects on soil organic matter and soil fertility.

  6. Optimal weed management in crop rotations: incorporating economics is crucial

    NARCIS (Netherlands)

    Berg, van den F.; Gilligan, C.A.; Lemmen-Gerdessen, van J.C.; Gregoire, L.A.H.; Bosch, van den F.

    2010-01-01

    Although the effects of crop rotation sequence and length on weed population dynamics have been studied, it is not clear whether or not the best strategy, from a weed population dynamics point of view, is also the economic optimal strategy. It is also not clear which biological and economic paramete

  7. Long-term Studies on Crop-pasture Rotations and Different Tillage Systems in Uruguay%乌拉圭的作物-牧草轮作和耕作体系长期观测研究

    Institute of Scientific and Technical Information of China (English)

    刘晓冰; 张兴义; Oswaldo Ernst; Mario Perez-Bidegain

    2016-01-01

    不同于世界其他黑土区,始于20世纪60年代乌拉圭的作物-牧草轮作制是很有影响和特色的种植体系。它是一个更具多样性,具有更强的抗御气候和经济变化缓冲力的系统。本文介绍了乌拉圭作物-牧草轮作几个体系的构成,重点评述了基于作物-牧草多体轮作制长期定位试验不同耕作体系对土壤有机碳动态、土壤侵蚀和氧化亚氮排放的影响。特定生态环境和特别的种植体系下得出的不同于其他地区的研究结果或结论,对进一步深入理解农业生产的区域性意义重大。表3,参21。%Crop-pasture rotations in Uruguay since 1960s, the predominant and unusual cropping systems around the world are the most influential farming systems. This system is a more economically and climatically buffered system due to its higher diversity. This paper describes the basic components of several crop-pasture rotations, and summarizes the impacts of long-and middle-term crop-pas-ture rotations under different tillage systems on soil organic carbon, soil erosion and nitrous oxide emissions. Different results and con-clusions obtained from the given ecological conditions and cropping systems in Uruguay lends significance in further understanding the importance of regional variability for agricultural production.

  8. 洱海北部地区不同轮作农田氮、磷流失特性研究%Characteristics of Nitrogen and Phosphorus Losses in Different Crop Rotation Systems in the North of Erhai Lake Basin

    Institute of Scientific and Technical Information of China (English)

    汤秋香; 任天志; 雷宝坤; 翟丽梅; 胡万里; 张继宗; 林涛; 刘宏斌

    2012-01-01

    [目的]本文通过研究洱海北部地区不同轮作模式下农田氮、磷流失特征以期为环境污染风险评估和制定相关措施控制由农业造成的面源污染提供参考。[方法]试验中通过调查采自洱海北部地区7个乡镇4种不同种植模式下的水样及施肥情况分析了田面水和沟渠水的氮、磷含量动态变化情况,以及肥料的投入量与田面水和沟渠水中氮、磷浓度的关系。[结果]田面水中,不同轮作模式下氮素的流失差异显著,蚕豆-水稻比大蒜-水稻模式减少氮素流失风险38%。水溶态氮是氮流失的主要形态。可溶性氮浓度以大蒜-水稻模式最高。不同轮作模式下田面水中氮浓度基本趋势为:大蒜-水稻〉黑麦草-水稻〉蚕豆-水稻〉油菜-水稻。磷素流失总量偏低,且以泥沙结合态为主,不同轮作模式间各种形态的磷流失无显著差异。田面水中氮磷含量比沟渠水高,对总氮和总磷的增荷率分别为73%和82%。追肥是导致农田水对沟渠水增荷的关键因素。[结论]本研究中,大蒜-水稻是洱海流域农田氮磷流失风险最高的轮作模式。因此,应该综合考虑环境效益和经济效益,合理安排轮作模式。本研究为控制洱海流域农田面源污染和改善洱海水质提供了参考。%[Objective] Nitrogen and phosphorus losses of surface runoff in various crop rotation systems in the north of Erhai Lake basin were studied with the objective to provide references for risk evaluation of environmental pollution and formulating countermeasures to control the nonpoint source pollution from agriculture.[Method] Water samples collected in four typical crop rotation systems distributed in seven towns(townships) in the north of Erhai Lake basin were investigated,as well as the fertilizer input,to explore the dynamic change of nitrogen and phosphorus content in surface water of farmland and ditch water,and the correlation between fertilizer

  9. Carbon Turnover in a Crop Rotation Under Free Air CO2 Enrichment (FACE)

    Institute of Scientific and Technical Information of China (English)

    H. J. WEIGEL; K. LEWIN; J. NAGY; A. PACHOLSKI; S. BURKART; M. HELAL; O. HEINEMEYER; B. KLEIKAMP; R. MANDERSCHEID; C. FR(U)HAUF; G. F. HENDREY

    2005-01-01

    Mostly based on assumptions derived from controlled-environment studies, predicted future atmospheric CO2 concentrations [CO2] are expected to have considerable impacts on carbon (C) turnover in agro-ecosystems. In order to allow the in situ examination of C-transformations in the plant-soil system of arable crop rotations under future [CO2], a free air carbon dioxide enrichment (FACE) experiment (550 μmol mol-1 CO2) was started at Braunschweig, Germany in 1999.The crop rotation under investigation comprised winter barley, a cover crop (ryegrass), sugar beets and winter wheat.Assessments of CO2 effects included the determination of above- and belowground biomass production, measurements of canopy CO2- and H2O- fluxes, soil microbial biomass and in situ soil respiration. The results obtained during the 1st crop rotation cycle (3 years) showed that for the selected crops elevated [CO2] entailed significant positive effects (P<0.05) on aboveground (6%-14% stimulation) and belowground biomass production (up to 90% stimulation), while canopy evapotranspiration was reduced. This resulted in increased soil water content. Also, depending on crop type and season, high CO2 stimulated in situ soil respiration (up to 30%), while soil microbial biomass did not show significant respoases to elevated [CO2] during the first rotation cycle.

  10. Environmental enhancement using short-rotation woody crops and perennial grasses as alternative agricultural crops

    Energy Technology Data Exchange (ETDEWEB)

    Tolbert, V.R. [Oak Ridge National Lab., TN (United States); Schiller, A. [Oak Ridge Inst. for Science and Education, TN (United States)

    1996-10-01

    Short-rotation woody crops and perennial grasses are grown as biomass feedstocks for energy and fiber. When replacing traditional row crops on similar lands, these alternative crops can provide multiple environmental benefits in addition to enhancing rural economies and providing valuable resources. The DOE is supporting research to address how these crops can provide environmental benefits to soil, water, and native wildlife species in addition to providing bioenergy feedstocks. Research is underway to address the potential for biomass crops to provide soils conservation and water quality improvements in crop settings. Replacement of traditional erosive row drops with biomass crops on marginal lands and establishment of biomass plantations as filter strips adjacent to streams and wetlands are being studied. The habitat value of different crops for wildlife species is also considered. Combining findings on wildlife use of individual plantations with information on the cumulative effects of multiple plantations on wildlife populations can provide guidance for establishing and managing biomass crops to enhance biodiversity while providing feedstocks. Data from site-specific environmental studies can provide input for evaluation of the effects of large-scale plantings at both landscape and regional levels of resolution.

  11. Influence of tillage practices and straw incorporation on soil aggregates, organic carbon, and crop yields in a rice-wheat rotation system

    Science.gov (United States)

    Song, Ke; Yang, Jianjun; Xue, Yong; Lv, Weiguang; Zheng, Xianqing; Pan, Jianjun

    2016-11-01

    In this study, a fixed-site field experiment was conducted to study the influence of different combinations of tillage and straw incorporation management on carbon storage in different-sized soil aggregates and on crop yield after three years of rice-wheat rotation. Compared to conventional tillage, the percentages of >2 mm macroaggregates and water-stable macroaggregates in rice-wheat double-conservation tillage (zero-tillage and straw incorporation) were increased 17.22% and 36.38% in the 0–15 cm soil layer and 28.93% and 66.34% in the 15–30 cm soil layer, respectively. Zero tillage and straw incorporation also increased the mean weight diameter and stability of the soil aggregates. In surface soil (0–15 cm), the maximum proportion of total aggregated carbon was retained with 0.25–0.106 mm aggregates, and rice-wheat double-conservation tillage had the greatest ability to hold the organic carbon (33.64 g kg‑1). However, different forms occurred at higher levels in the 15–30 cm soil layer under the conventional tillage. In terms of crop yield, the rice grown under conventional tillage and the wheat under zero tillage showed improved equivalent rice yields of 8.77% and 6.17% compared to rice-wheat double-cropping under zero tillage or conventional tillage, respectively.

  12. Effect of crop rotation on populations of Epitrix tuberis (Coleoptera: Chrysomelidae) in potato.

    Science.gov (United States)

    Kabaluk, J T; Vernon, R S

    2000-04-01

    The effect of crop rotation on populations of tuber flea beetle, Epitrix tuberis Gentner, in potatoes was investigated using data supplied by an integrated pest management (IPM) company and Geographic Information System software and conventional statistical methods. Using combined 1995 and 1996 data, beetles of the overwintered and F1 generations in both the interior and edges of potato fields showed a significant linear increase with an increase in the preceding consecutive years (0, 1, and 2 years) that the current years' crop was planted to potatoes. Populations were significantly higher in nonrotated fields compared with rotated fields. Both the percentage of the cropping region requiring insecticidal control of tuber flea beetles and the cost of insecticides per hectare of potatoes grown increased linearly with an increase in the number of previous years planted to potatoes. Not practicing crop rotation resulted in a 4.2-7.3% increase in the cropping region requiring insecticidal control of tuber flea beetles. The cost of controlling beetles in potato fields planted to potatoes for 3 consecutive years was up to $20/ha greater than potatoes rotated from the preceding year. Beetle counts from the interior of rotated potato fields never exceeded threshold levels when field edges also were below threshold. It is concluded that sampling of overwintered beetles in interior sites of rotated fields could be abandoned, and only 1 monitoring scout rather than 2 would be necessary to monitor a field during this time. From these results, we concluded that rotating potato crops would reduce spray costs to the farmer and monitoring costs to IPM companies.

  13. [Main bacterial groups in banana soil under rotated and continuous cropping].

    Science.gov (United States)

    Ouyang, Xian; Ruan, Xiao-Lei; Wu, Chao; Bai, Ting-Ting; Li, Hua-Ping

    2011-06-01

    Banana wilt is the main disease in banana production, while banana-leek rotation can effectively control the occurrence of the disease. In order to understand the variations of soil bacterial groups under banana-leek rotation and banana continuous cropping, soil samples under these two cropping systems were collected to extract crude DNA, and the bacterial 16S rDNA in V3 region was amplified by PCR. The PCR products were then separated by DGGE, and the main different bands were sequenced and compared with the records of NCBI to identify the germs. Under banana-leek rotation, soil bacterial diversity was richer, and the main bacterial groups were Bacteroidetes, Proteobacteria, Actinobacteria, Chloroflexi, and Acidobacteria; while under banana continuous cropping, the soil bacterial diversity was somewhat decreased, and the main bacterial groups were Firmicutes, Proteobacteria, Actinobacteria, and Chloroflexi.

  14. Short rotation woody crops: Using agroforestry technology for energy in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Wright, L L; Ranney, J W

    1991-01-01

    Agroforestry in the United States is being primarily defined as the process of using trees in agricultural systems for conservation purposes and multiple products. The type of agroforestry most commonly practiced in many parts of the world, that is the planting of tree crops in combination with food crops or pasture, is the type least commonly practiced in the United States. One type of agroforestry technique, which is beginning now and anticipated to expand to several million acres in the United States, is the planting of short-rotation woody crops (SRWCs) primarily to provide fiber and fuel. Research on SRWC's and environmental concerns are described.

  15. Simulating Stochastic Crop Management in Cropping Systems

    Science.gov (United States)

    Introduction -- Crop simulation models are uniquely suitable for examining long term crop responses to environmental variability due to changes in climate or other factors. Long-term studies typically emphasize variability related to weather conditions; certain weather-dependent cropping practices m...

  16. Soil carbon and crop yields affected by irrigation, tillage, crop rotation, and nitrogen fertilization

    Science.gov (United States)

    Information on management practices is needed to increase surface residue and soil C sequestration to obtain farm C credit. The effects of irrigation, tillage, cropping system, and N fertilization were evaluated on the amount of crop biomass (stems and leaves) returned to the soil, surface residue C...

  17. Cover crop management practices-implications for early season weed control in conservation tillage corn cotton rotation

    Science.gov (United States)

    Use of the winter cover crops is an integral component of the conservation systems in corn (Zea mays L.) and cotton (Gossypium hirsutum L.). A field experiment was initiated in 2004 to evaluate weed suppression provided by winter cover crops in a conservation tillage corn and cotton rotation. Rotati...

  18. Yield trends in the long-term crop rotation with organic and inorganic fertilisers on Alisols in Mata (Rwanda)

    NARCIS (Netherlands)

    Rutunga, V.; Neel, H.

    2006-01-01

    A crop rotation system with various species was established on Alisols at Mata grassland site, oriental side of Zaire-Nile Watershed Divide (CZN), Rwanda. Inorganic and organic fertilizers were applied in various plots under randomized complete blocs with three replicates. Crop yield data for each s

  19. Limited irrigation of corn-based no-till crop rotations in west central Great Plains.

    Science.gov (United States)

    Identifying the most profitable crop rotation for an area is a continuous research challenge. The objective of this study was to evaluate 2, 3, and 4 yr. limited irrigation corn (Zea mays L.) based crop rotations for grain yield, available soil water, crop water productivity, and profitability in co...

  20. Effect of diversified crop rotations on groundwater levels and crop water productivity in the North China Plain

    Science.gov (United States)

    Yang, Xiaolin; Chen, Yuanquan; Pacenka, Steven; Gao, Wangsheng; Ma, Li; Wang, Guangya; Yan, Peng; Sui, Peng; Steenhuis, Tammo S.

    2015-03-01

    Water shortage is the major bottleneck that limits sustainable yield of agriculture in the North China Plain. Due to the over-exploitation of groundwater for irrigating the winter wheat-summer maize double cropping systems, a groundwater crisis is becoming increasingly serious. To help identify more efficient and sustainable utilization of the limited water resources, the water consumption and water use efficiency of five irrigated cropping systems were calculated and the effect of cropping systems on groundwater table changes was estimated based on a long term field experiment from 2003 to 2013 in the North China Plain interpreted using a soil-water-balance model. The five cropping systems included sweet potato → cotton → sweet potato → winter wheat-summer maize (SpCSpWS, 4-year cycle), ryegrass-cotton → peanuts → winter wheat-summer maize (RCPWS, 3-year cycle), peanuts → winter wheat-summer maize (PWS, 2-year cycle), winter wheat-summer maize (WS, 1-year cycle), and continuous cotton (Cont C). The five cropping systems had a wide range of annual average actual evapotranspiration (ETa): Cont C (533 mm/year) RCPWS (0.7 m/year) > PWS (0.6 m/year) > SPCSPWS and Cont C (0.4 m/year). The annual average economic output water use efficiency (WUEe) increased in the order SpCSpWS (11.6 yuan ¥ m-3) > RCPWS (9.0 ¥ m-3) > PWS (7.3 ¥ m-3) > WS (6.8 ¥ m-3) > Cont C (5.6 ¥ m-3) from 2003 to 2013. Results strongly suggest that diversifying crop rotations could play a critically important role in mitigating the over-exploitation of the groundwater, while ensuring the food security or boosting the income of farmers in the North China Plain.

  1. Climate protection and energy crops. Potential for greenhouse gas emission reduction through crop rotation and crop planning; Klimaschutz und Energiepflanzenanbau. Potenziale zur Treibhausgasemissionsminderung durch Fruchtfolge- und Anbauplanung

    Energy Technology Data Exchange (ETDEWEB)

    Eckner, Jens [Thueringer Landesanstalt fuer Landwirtschaft (Germany); Peter, Christiane; Vetter, Armin

    2015-07-01

    The EVA project compares nationwide energy crops and crop rotations on site-specific productivity. In addition to agronomic suitability for cultivation economic and environmental benefits and consequences are analyzed and evaluated. As part of sustainability assessment of the tested cultivation options LCAs are established. The model MiLA developed in the project uses empirical test data and site parameters to prepare the inventory balances. At selected locations different cultivation and fertilization regimes are examined comparatively. In the comparison of individual crops and crop rotation combinations cultivation of W.Triticale-GPS at the cereals favor location Dornburg causes the lowest productrelated GHG-emissions. Due to the efficient implementation of nitrogen and the substrate properties of maize is the cultivation despite high area-related emissions and N-expenses at a low level of emissions. Because of the intensity the two culture systems offer lower emissions savings potentials with high area efficiency. Extensification with perennial alfalfagrass at low nitrogen effort and adequate yield performance show low product-related emissions. Closing the nutrient cycles through a recirculation of digestates instead of using mineral fertilization has a climate-friendly effect. Adapted intensifies of processing or reduced tillage decrease diesel consumption and their related emissions.

  2. No tillage combined with crop rotation improves soil microbial community composition and metabolic activity.

    Science.gov (United States)

    Sun, Bingjie; Jia, Shuxia; Zhang, Shixiu; McLaughlin, Neil B; Liang, Aizhen; Chen, Xuewen; Liu, Siyi; Zhang, Xiaoping

    2016-04-01

    Soil microbial community can vary with different agricultural managements, which in turn can affect soil quality. The objective of this work was to evaluate the effects of long-term tillage practice (no tillage (NT) and conventional tillage (CT)) and crop rotation (maize-soybean (MS) rotation and monoculture maize (MM)) on soil microbial community composition and metabolic capacity in different soil layers. Long-term NT increased the soil organic carbon (SOC) and total nitrogen (TN) mainly at the 0-5 cm depth which was accompanied with a greater microbial abundance. The greater fungi-to-bacteria (F/B) ratio was found in NTMS at the 0-5 cm depth. Both tillage and crop rotation had a significant effect on the metabolic activity, with the greatest average well color development (AWCD) value in NTMS soil at all three soil depths. Redundancy analysis (RDA) showed that the shift in microbial community composition was accompanied with the changes in capacity of utilizing different carbon substrates. Therefore, no tillage combined with crop rotation could improve soil biological quality and make agricultural systems more sustainable.

  3. Nitrate leaching from organic arable crop rotations is mostly determined by autumn field management

    DEFF Research Database (Denmark)

    Askegaard, M; Olesen, Jørgen E; Rasmussen, Ilse Ankjær;

    2011-01-01

    in the manured treatments the application rate was lower than crop demand. The results identify management of crop and soil during autumn as the main determinant of N leaching. Nitrate leaching was lowest for a catch crop soil cover during autumn and winter (avg. 20 kg N ha−1), a soil cover of weeds......Two main challenges facing organic arable farming are the supply of nitrogen (N) to the crop and the control of perennial weeds. Nitrate leaching from different organic arable crop rotations was investigated over three consecutive four-year crop rotations in a field experiment at three locations...... in Denmark (12 years in total). The experimental treatments were: (i) crop rotation, (ii) catch crop and (iii) animal manure. Nitrate leaching was estimated from measured soil nitrate concentration in ceramic suction cells and modelled drainage. There were significant effects on annual N leaching of location...

  4. Studies on Water Consumption Characteristics and Crops Rotation Effects in Plateau of Northern Hebei Province

    Institute of Scientific and Technical Information of China (English)

    ZHANG Li-feng; BIAN Xiu-ju; LIU Yu-hua

    2002-01-01

    Experiments were carried out in 1994 - 1998 to study crop rotation and its effects on crop water consumption characteristics of field with sandy chestnut soil in the Plateau of north Hebei Province. Five crops including spring wheat, oat, pea, flax and potato were examined. There was little difference in field water consumption among the crops during the growing season. WUE varied significantly in a range of 1. 347 - 11.177kg · ha-1· mm-1 among crops and 11.44% - 46.66% among previous crops. It was pointed out that the land equivalent ratio (LER) can be used as an index to evaluate the biological effects of crop rotation comprehensively. The 2 - 4 year crop rotation patterns with higher LER were estimated in the paper.

  5. Effects of potato-cotton cropping systems and nematicides on plant-parasitic nematodes and crop yields.

    Science.gov (United States)

    Crow, W T; Weingartner, D P; Dickson, D W

    2000-09-01

    Belonolaimus longicaudatus has been reported as damaging both potato (Solanum tuberosum) and cotton (Gossypium hirsutum). These crops are not normally grown in cropping systems together in areas where the soil is infested with B. longicaudatus. During the 1990s cotton was grown in a potato production region that was a suitable habitat for B. longicaudatus. It was not known how integrating the production of these two crops by rotation or double-cropping would affect the population densities of B. longicaudatus, other plant-parasitic nematodes common in the region, or crop yields. A 3-year field study evaluated the viability of both crops in monocropping, rotation, and double-cropping systems. Viability was evaluated using effects on population densities of plant-parasitic nematodes and yields. Rotation of cotton with potato was found to decrease population densities of B. longicaudatus and Meloidogyne incognita in comparison with continuous potato. Population densities of B. longicaudatus following double-cropping were greater than following continuous cotton. Yields of both potato and cotton in rotation were equivalent to either crop in monocropping. Yields of both crops were lower following double-cropping when nematicides were not used.

  6. The Effect of Crop Rotation on Soil Nematode Community Composition in a Greenhouse

    Institute of Scientific and Technical Information of China (English)

    Jingwen LU; Wei SHENG; Qian YU; Zijing CHEN; Qiang XU; Qian WANG; Linlin DONG

    2015-01-01

    Objective] The aim was to identify changes in a nematode community in response to crop rotation and to determine the appropriate catch crop for a green-house. [Method] The experiment was carried out in a typical 6-year-old greenhouse, in which cucumber crops were cultivated twice each year (in spring and autumn), and catch crops were planted in summer. The total number of nematodes was counted and nematode community indices were calculated after col ecting soil sam-ples in different stages. [Result] Total nematode abundance was decreased in the soils of catch crop in contrast with former crops (cucumber crops). The abundance of the nematode community was reduced in the treatment of crop rotation compared to the soils of catch crop. ln addition, the number of nematode taxa was significant-ly reduced by the treatment of crown daisy compared to the treatments of fol owing crops. Crop rotation regulated the functional composition of the nematode community by increasing the omnivores-predators functional group and decreasing the relative abundance of root herbivores. [Conclusion] These results indicate that crop rotation affects the nematode community in abundance, diversity and functional composition of the nematode community and crown daisy can be served as the most appropri-ate catch crop in the greenhouse.

  7. Topography Mediates the Influence of Cover Crops on Soil Nitrate Levels in Row Crop Agricultural Systems.

    Science.gov (United States)

    Ladoni, Moslem; Kravchenko, Alexandra N; Robertson, G Phillip

    2015-01-01

    Supplying adequate amounts of soil N for plant growth during the growing season and across large agricultural fields is a challenge for conservational agricultural systems with cover crops. Knowledge about cover crop effects on N comes mostly from small, flat research plots and performance of cover crops across topographically diverse agricultural land is poorly understood. Our objective was to assess effects of both leguminous (red clover) and non-leguminous (winter rye) cover crops on potentially mineralizable N (PMN) and [Formula: see text] levels across a topographically diverse landscape. We studied conventional, low-input, and organic managements in corn-soybean-wheat rotation. The rotations of low-input and organic managements included rye and red clover cover crops. The managements were implemented in twenty large undulating fields in Southwest Michigan starting from 2006. The data collection and analysis were conducted during three growing seasons of 2011, 2012 and 2013. Observational micro-plots with and without cover crops were laid within each field on three contrasting topographical positions of depression, slope and summit. Soil samples were collected 4-5 times during each growing season and analyzed for [Formula: see text] and PMN. The results showed that all three managements were similar in their temporal and spatial distributions of NO3-N. Red clover cover crop increased [Formula: see text] by 35% on depression, 20% on slope and 32% on summit positions. Rye cover crop had a significant 15% negative effect on [Formula: see text] in topographical depressions but not in slope and summit positions. The magnitude of the cover crop effects on soil mineral nitrogen across topographically diverse fields was associated with the amount of cover crop growth and residue production. The results emphasize the potential environmental and economic benefits that can be generated by implementing site-specific topography-driven cover crop management in row-crop

  8. Topography Mediates the Influence of Cover Crops on Soil Nitrate Levels in Row Crop Agricultural Systems.

    Directory of Open Access Journals (Sweden)

    Moslem Ladoni

    Full Text Available Supplying adequate amounts of soil N for plant growth during the growing season and across large agricultural fields is a challenge for conservational agricultural systems with cover crops. Knowledge about cover crop effects on N comes mostly from small, flat research plots and performance of cover crops across topographically diverse agricultural land is poorly understood. Our objective was to assess effects of both leguminous (red clover and non-leguminous (winter rye cover crops on potentially mineralizable N (PMN and [Formula: see text] levels across a topographically diverse landscape. We studied conventional, low-input, and organic managements in corn-soybean-wheat rotation. The rotations of low-input and organic managements included rye and red clover cover crops. The managements were implemented in twenty large undulating fields in Southwest Michigan starting from 2006. The data collection and analysis were conducted during three growing seasons of 2011, 2012 and 2013. Observational micro-plots with and without cover crops were laid within each field on three contrasting topographical positions of depression, slope and summit. Soil samples were collected 4-5 times during each growing season and analyzed for [Formula: see text] and PMN. The results showed that all three managements were similar in their temporal and spatial distributions of NO3-N. Red clover cover crop increased [Formula: see text] by 35% on depression, 20% on slope and 32% on summit positions. Rye cover crop had a significant 15% negative effect on [Formula: see text] in topographical depressions but not in slope and summit positions. The magnitude of the cover crop effects on soil mineral nitrogen across topographically diverse fields was associated with the amount of cover crop growth and residue production. The results emphasize the potential environmental and economic benefits that can be generated by implementing site-specific topography-driven cover crop management

  9. Verticillium dahliae Infects, Alters Plant Biomass, and Produces Inoculum on Rotation Crops.

    Science.gov (United States)

    Wheeler, D L; Johnson, D A

    2016-06-01

    Verticillium wilt, caused by Verticillium dahliae, reduces yields of potato and mint. Crop rotation is a potential management tactic for Verticillium wilt; however, the wide host range of V. dahliae may limit the effectiveness of this tactic. The hypothesis that rotation crops are infected by V. dahliae inoculum originating from potato and mint was tested by inoculation of mustards, grasses, and Austrian winter pea with eight isolates of V. dahliae. Inoculum density was estimated from plants and soil. Typical wilt symptoms were not observed in any rotation crop but plant biomass of some crops was reduced, not affected, or increased by infection of specific isolates. Each isolate was host-specific and infected a subset of the rotation crops tested but microsclerotia from at least one isolate were observed on each rotation crop. Some isolates were host-adapted and differentially altered plant biomass or produced differential amounts of inoculum on rotation crops like arugula and Austrian winter pea, which supported more inoculum of specific isolates than potato. Evidence of asymptomatic and symptomatic infection and differential inoculum formation of V. dahliae on rotation crops presented here will be useful in designing rotations for management of Verticillium wilt.

  10. Characteristics of nitrogen and phosphorus loss in various crop rotation systems in northern watershed of Erhai Lake%洱海北部地区不同轮作农田氮、磷流失特性研究

    Institute of Scientific and Technical Information of China (English)

    汤秋香; 任天志; 雷宝坤; 翟丽梅; 胡万里; 张继宗; 林涛; 刘宏斌

    2011-01-01

    为明确洱海北部地区不同轮作模式下农田氮、磷流失特性,客观评价环境污染风险.试验在洱海北部地区沿弥苴河和罗时江流域的7个乡镇进行.采用定点取样与实地调研相结合的方法进行多点重复监测,调查不同轮作模式、轮作周期内田面水和沟渠水的氮、磷含量变化情况,研究不同轮作模式下氮、磷污染的负荷及其影响因素.结果表明,田面水中,不同轮作模式下氮素的流失差异显著且以水溶态为主,可溶性氮浓度以大蒜-水稻模式最高,油菜-水稻模式最低,其它轮作模式居中分布;降雨径流氮流失量以大蒜-水稻模式最高.磷素流失总量偏低,且以泥沙结合态为主,轮作模式间无显著差异.田面水质劣于沟渠水,田面水对沟渠水存在不司程度增荷作用;农田水对沟渠水总氮和总磷的增荷率分别为73%和82%,其中追肥是导致农田水对沟渠水增荷的关键因素.本研究中,大蒜-水稻是洱海流域农田氮、磷流失风险最高的种植模式;蚕豆-水稻比大蒜-水稻模式减少氮素流失风险38%.因此,应综合考虑环境效益和经济效益,合理安排种植结构,为洱海流域种植结构调整、控制农田面源污染提供参考.%Nitrogen and phosphorus losses of surface runoff in various crop rotation systems in north of lake Erhai watershed were researched for the risk evaluation and putting countermeasures for the nonpoint pollution from agricultural source. Pollution loads of nitrogen and phosphorus were studied in four typical crop rotation systems by using the influencing factors, by analyzing the content variation dynamic of nitrogen and phosphorus in surface water of farmland and ditch water in 7 townships of northern lake Erhai watershed. The results show that the water soluble nitrogen is main loss of runoff water, and the contents of nitrogen have significantly contrast in farmland surface water of different crop rotation systems

  11. Effect of organic and conventional crop rotation, fertilization, and crop protection practices on metal contents in wheat (Triticum aestivum).

    Science.gov (United States)

    Cooper, Julia; Sanderson, Roy; Cakmak, Ismail; Ozturk, Levent; Shotton, Peter; Carmichael, Andrew; Haghighi, Reza Sadrabadi; Tetard-Jones, Catherine; Volakakis, Nikos; Eyre, Mick; Leifert, Carlo

    2011-05-11

    The effects of organic versus conventional crop management practices (crop rotation, crop protection, and fertility management strategies) on wheat yields and grain metal (Al, Cd, Cu, Ni, Pb, and Zn) concentrations were investigated in a long-term field trial. The interactions between crop management practices and the season that the crop was grown were investigated using univariate and redundancy analysis approaches. Grain yields were highest where conventional fertility management and crop protection practices were used, but growing wheat after a previous crop of grass/clover was shown to partially compensate for yield reductions due to the use of organic fertility management. All metals except for Pb were significantly affected by crop management practices and the year that the wheat was grown. Grain Cd and Cu levels were higher on average when conventional fertility management practices were used. Al and Cu were higher on average when conventional crop protection practices were used. The results demonstrate that there is potential to manage metal concentrations in the diet by adopting specific crop management practices shown to affect crop uptake of metals.

  12. Impact of crop rotation and soil amendments on long-term no-tilled soybean yields

    Science.gov (United States)

    Continuous cropping systems without cover crops are perceived as unsustainable for long-term yield and soil health. To test this, cropping sequence and cover crop effects on soybean (Glycine max L.) yields were assessed. Main effects were 10 cropping sequences of soybean, corn (Zea mays L.), and co...

  13. Enhancing Soil Productivity Using a Multi-Crop Rotation and Beef Cattle Grazing

    Science.gov (United States)

    Şentürklü, Songül; Landblom, Douglas; Cihacek, Larry; Brevik, Eric

    2016-04-01

    . Crop yields were as follows for the 5 crop years in the study (2011-2015): (1) CC was 0.25, 10.5, 8.03, 1.53, and 7.22t/ha, (2) C silage was 4.08, 9.04, 9.91, 8.65, and 14.4 t/ha, (3) C grain was 1.04, 3.81, 6.09, 3.11, and 5.1 t/ha, (4) SF was 1.10, 1.96, 2.42, 1.31, and 2.29 t/ha, (5) PBY forage was 0.0, 7.68, 11.2, 9.3, and 8.72 t/ha. When cattle grazed annual forage crops (C, PBY, and CC), animal manure and trampling contributed to the overall improvement of soil fertility. These data suggest that the combined effect of a multi-crop rotation that includes animal grazing enhances soil fertility and subsequently crop yields, and animal production for a sustainable integrated agricultural system.

  14. Effectiveness of the GAEC standard of cross compliance Crop rotations in maintaining organic matter levels in soils

    Directory of Open Access Journals (Sweden)

    Lamberto Borrelli

    2011-08-01

    Full Text Available Our study was conducted in the framework of EFFICOND project, with the aim of evaluating the environmental effectiveness of GAEC (Good Agricultural and Environmental Conditions standards with particular focus to the maintenance of soil organic matter (SOM levels through the appropriate crop rotation. The study analyzed the effect of crop rotation on the build-up of soil organic matter in three different areas of Italy, located in the North (Lodi, Centre (Fagna, Firenze and South (Foggia of Italy, characterized by different climate, soil, and cropping systems. In the two experiments conducted in the South of Italy, in a dry Mediterranean climate, the stock of C was kept steady in most of the rotations compared with the monoculture of durum wheat. In such environment, with very dry and hot summers, introducing a year of fallow seems to improve SOM content, but these data need further investigation. In the Centre of Italy (Fagna, with less extreme climate than in Foggia, the effect of rotation compared to the monoculture of maize is negligible, but investigation on the soil organic matter composition, showed that in the rotation the SOM appeared to be more stable and, in the long term, probably more resistant to degradation. Eventually, experiments conducted in the North of Italy, showed that the monoculture, despite the application of FYM (Farm Yard Manure or semi-liquid manure, led to a decrease of SOM. To an increase of the rotation complexity, corresponded an increase in the stock of C in soil. Summarizing, results showed that crop rotation could guarantee the maintenance of SOM level, given that the input of C to the soil is maintained at a good level or, in other word, that productivity of the system is high. Other practices such as conservation tillage, appropriate management of residues, and manure application could enhance the positive effect of rotations. Moreover, preliminary investigation of soil microbial diversity, suggests the

  15. Effect of temperature and precipitation on nitrate leaching from organic cereal cropping systems in Denmark

    DEFF Research Database (Denmark)

    Jabloun, Mohamed; Schelde, Kirsten; Tao, F;

    2015-01-01

    management. There were significant effects on annual N concentration and NO3single bondN leaching of location, rotation, previous crop and crop cover during autumn and winter. The relative effects of temperature and precipitation differed between seasons and cropping systems. A sensitivity analysis revealed......The effect of variation in seasonal temperature and precipitation on soil water nitrate (NO3single bondN) concentration and leaching from winter and spring cereals cropping systems was investigated over three consecutive four-year crop rotation cycles from 1997 to 2008 in an organic farming crop...... rotation experiment in Denmark. Three experimental sites, varying in climate and soil type from coarse sand to sandy loam, were investigated. The experiment included experimental treatments with different rotations, manure rate and cover crop, and soil nitrate concentrations was monitored using suction...

  16. Crop rotations in the sea: Increasing returns and reducing risk of collapse in sea cucumber fisheries.

    Science.gov (United States)

    Plagányi, Éva Elizabeth; Skewes, Timothy; Murphy, Nicole; Pascual, Ricardo; Fischer, Mibu

    2015-05-26

    Rotational harvesting is one of the oldest management strategies applied to terrestrial and marine natural resources, with crop rotations dating back to the time of the Roman Empire. The efficacy of this strategy for sessile marine species is of considerable interest given that these resources are vital to underpin food security and maintain the social and economic wellbeing of small-scale and commercial fishers globally. We modeled the rotational zone strategy applied to the multispecies sea cucumber fishery in Australia's Great Barrier Reef Marine Park and show a substantial reduction in the risk of localized depletion, higher long-term yields, and improved economic performance. We evaluated the performance of rotation cycles of different length and show an improvement in biological and economic performance with increasing time between harvests up to 6 y. As sea cucumber fisheries throughout the world succumb to overexploitation driven by rising demand, there has been an increasing demand for robust assessments of fishery sustainability and a need to address local depletion concerns. Our results provide motivation for increased use of relatively low-information, low-cost, comanagement rotational harvest approaches in coastal and reef systems globally.

  17. Controlling annual weeds in cereals by deploying crop rotation at the landscape scale: Avena sterilis as an example.

    Science.gov (United States)

    González-Díaz, Lucía; van den Berg, Femke; van den Bosch, Frank; González-Andújar, José Luis

    2012-04-01

    Weed control through crop rotation has mainly been studied in a nonspatial context. However, weed seeds are often spread beyond the crop field by a variety of vectors. For weed control to be successful, weed management should thus be evaluated at the landscape level. In this paper we assess how seed dispersal affects the interactions between crop rotation and landscape heterogeneity schemes with regard to weed control. A spatially explicit landscape model was developed to study both short- and long-term weed population dynamics under different management scenarios. We allowed for both two- and three-crop species rotations and three levels of between-field weed seed dispersal. All rotation scenarios and seed dispersal fractions were analyzed for both completely homogeneous landscapes and heterogeneous landscapes in which more than one crop was present. The potential of implementing new weed control methods was also analyzed. The model results suggest that, like crop rotation at the field level, crop rotation implemented at the landscape level has great potential to control weeds, whereby both the number of crop species and the cropping sequence within the crop rotation have significant effects on both the short- and long-term weed population densities. In the absence of seed dispersal, weed populations became extinct when the fraction of each crop in the landscape was randomized. In general, weed seed densities increased in landscapes with increasing similarity in crop proportions, but in these landscapes the level of seed dispersal affected which three-crop species rotation sequence was most efficient at controlling the weed densities. We show that ignoring seed dispersal between fields might lead to the selection of suboptimal tactics and that homogeneous crop field patches that follow a specific crop rotation sequence might be the most sustainable method of weed control. Effective weed control through crop rotation thus requires coordination between farmers with

  18. Emissions of nitrous oxide from arable organic and conventional cropping systems on two soil types

    DEFF Research Database (Denmark)

    Chirinda, N.; Carter, Mette Sustmann; Albert, Kristian Rost

    2010-01-01

    . The main objective of this study was to compare nitrous oxide (N2O) emissions from soil under winter wheat (Triticum aestivum L.) within three organic and one conventional cropping system that differed in type of fertilizer, presence of catch crops and proportion of N2-fixing crops. The study......Conventional cropping systems rely on targeted short-term fertility management, whereas organic systems depend, in part, on long-term increase in soil fertility as determined by crop rotation and management. Such differences influence soil nitrogen (N) cycling and availability through the year...... was replicated in two identical long-term crop rotation experiments on sandy loam soils under different climatic conditions in Denmark (Flakkebjerg—eastern Denmark and Foulum—western Denmark). The conventional rotation received 165–170 kg N ha−1 in the form of NH4NO3, while the organic rotations received 100...

  19. Investigation of Present Fertilization on Crops by Different Rapeseed Rotation Systems in Hubei Province%湖北省不同油菜轮作模式下作物施肥现状调查

    Institute of Scientific and Technical Information of China (English)

    李银水; 余常兵; 廖星; 胡小加; 谢立华; 张树杰; 车志

    2012-01-01

    The aim was to establish high efficient fertilization technique system for rapeseed production in Hubei Province. This survey was conducted by spot field investigation to study the present situation of nutrient management and the problems existing in the fertilization technique on rapeseed by five rotation systems in Hubei Province. The results showed that, only 20.2% and 69.4% of the surveyed farmlands applied organic fertilizer and boron in rapeseed plating. The average application amount of nitrogen (N), phosphate (P) and potassium (K) fertilizer were 203.7, 71.3, 50.2 kg/hm2 respectively, which ratio was 1:0.35:0.25, and rapeseed average consume about 49.3%, 51.6% and 50.8% of the total N, P and K fertilizer used for a rotation period. The problems in rapeseed rotation systems nutrient management were displayed as follow: farmers applied excessive N fertilizer, and ignored the application of P and K fertilizer, especially for K. The ratio of N, P and K was imbalanced and the application amount of fertilizer different in regions and farmers. Excess and insufficient fertilization coexisted. The concept of the nutrient co-ordination by various rotation systems needed to be promoted. In addition, the application amount of the organic manure was low and the use of boron fertilizer need to popular. It suggested that, the nutrient management should take the characteristics of crop nutrient physiology need and cropping systems into consideration. At the same time, it was important to establish a new concept of sustainable agriculture fertilizer, so as to achieve maximum nutrient resources and promote the development of rapeseed and other planting.%为湖北省油菜生产建立高效施肥技术体系,通过农户走访调查,研究湖北省五类油菜轮作模式下的农户肥料施用情况及存在的主要问题.结果表明,湖北省油菜施用有机肥和硼肥的农户比例分别占20.2%和69.4%;油菜氮(N)、磷(P2O5)、钾(K2O

  20. Structural dynamics in rotating systems

    Science.gov (United States)

    Kiraly, Louis J.

    1993-01-01

    Major issues and recent advances in the structural dynamics of rotating systems are summarized. The objectives and benefits of such systems are briefly discussed. Directions for future research are suggested.

  1. Multi-model uncertainty analysis in predicting grain N for crop rotations in Europe

    DEFF Research Database (Denmark)

    Yin, Xiaogang; Kersebaum, Kurt C; Baby, Sanmohan;

    2017-01-01

    Realistic estimation of grain nitrogen (N; N in grain yield) is crucial for assessing N management in crop rotations, but there is little information on the performance of commonly used crop models for simulating grain N. Therefore, the objectives of the study were to (1) test if continuous simul...

  2. Crop rotations with annual and perennial forages under no-till soil management

    Science.gov (United States)

    Development of crop rotations that support sustainable agriculture depends on understanding complex relationships between soils, crops, and yield. Objectives were to measure how soil chemical and physical attributes as well as maize (Zea mays L.) and soybean [Glycine max (L.) Merr.] stover dry weig...

  3. Faba bean in cropping systems

    DEFF Research Database (Denmark)

    Steen Jensen, Erik; Peoples, Mark B.; Hauggaard-Nielsen, Henrik

    2010-01-01

    bean may prove to be a key component of future arable cropping systems where declining supplies and high prices of fossil energy are likely to constrain the affordability and use of fertilizers. This will help address the increasing demand by consumers and governments for agriculture to reduce its...... impact on the environment and climate through new, more sustainable approaches to food production. The aims of this paper are to review the role of faba bean in global plant production systems, the requirements for optimal faba bean production and to highlight the beneficial effects of faba bean...

  4. Grassland-Cropping Rotations: An Avenue for Agricultural Diversification to Reconcile High Production with Environmental Quality

    Science.gov (United States)

    Lemaire, Gilles; Gastal, François; Franzluebbers, Alan; Chabbi, Abad

    2015-11-01

    A need to increase agricultural production across the world to ensure continued food security appears to be at odds with the urgency to reduce the negative environmental impacts of intensive agriculture. Around the world, intensification has been associated with massive simplification and uniformity at all levels of organization, i.e., field, farm, landscape, and region. Therefore, we postulate that negative environmental impacts of modern agriculture are due more to production simplification than to inherent characteristics of agricultural productivity. Thus by enhancing diversity within agricultural systems, it should be possible to reconcile high quantity and quality of food production with environmental quality. Intensification of livestock and cropping systems separately within different specialized regions inevitably leads to unacceptable environmental impacts because of the overly uniform land use system in intensive cereal areas and excessive N-P loads in intensive animal areas. The capacity of grassland ecosystems to couple C and N cycles through microbial-soil-plant interactions as a way for mitigating the environmental impacts of intensive arable cropping system was analyzed in different management options: grazing, cutting, and ley duration, in order to minimize trade-offs between production and the environment. We suggest that integrated crop-livestock systems are an appropriate strategy to enhance diversity. Sod-based rotations can temporally and spatially capture the benefits of leys for minimizing environmental impacts, while still maintaining periods and areas of intensive cropping. Long-term experimental results illustrate the potential of such systems to sequester C in soil and to reduce and control N emissions to the atmosphere and hydrosphere.

  5. Grassland-Cropping Rotations: An Avenue for Agricultural Diversification to Reconcile High Production with Environmental Quality.

    Science.gov (United States)

    Lemaire, Gilles; Gastal, François; Franzluebbers, Alan; Chabbi, Abad

    2015-11-01

    A need to increase agricultural production across the world to ensure continued food security appears to be at odds with the urgency to reduce the negative environmental impacts of intensive agriculture. Around the world, intensification has been associated with massive simplification and uniformity at all levels of organization, i.e., field, farm, landscape, and region. Therefore, we postulate that negative environmental impacts of modern agriculture are due more to production simplification than to inherent characteristics of agricultural productivity. Thus by enhancing diversity within agricultural systems, it should be possible to reconcile high quantity and quality of food production with environmental quality. Intensification of livestock and cropping systems separately within different specialized regions inevitably leads to unacceptable environmental impacts because of the overly uniform land use system in intensive cereal areas and excessive N-P loads in intensive animal areas. The capacity of grassland ecosystems to couple C and N cycles through microbial-soil-plant interactions as a way for mitigating the environmental impacts of intensive arable cropping system was analyzed in different management options: grazing, cutting, and ley duration, in order to minimize trade-offs between production and the environment. We suggest that integrated crop-livestock systems are an appropriate strategy to enhance diversity. Sod-based rotations can temporally and spatially capture the benefits of leys for minimizing environmental impacts, while still maintaining periods and areas of intensive cropping. Long-term experimental results illustrate the potential of such systems to sequester C in soil and to reduce and control N emissions to the atmosphere and hydrosphere.

  6. How can we improve Mediterranean cropping systems?

    DEFF Research Database (Denmark)

    Benlhabib, O.; Yazar, A.; Qadir, M.;

    2014-01-01

    In the Mediterranean region, crop productivity and food security are closely linked to the adaptation of cropping systems to multiple abiotic stresses. Limited and unpredictable rainfall and low soil fertility have reduced agricultural productivity and environmental sustainability. For this reaso...

  7. Nitrogen input effectiveness on carbon sequestration in rainfed cropping system

    Science.gov (United States)

    Novara, Agata; Gristina, Luciano; Poma, Ignazio

    2016-04-01

    The combined effect of total N and C/N ratio had a large influence on the decomposition rate and consequently on potential soil organic carbon sequestration. The aim of the work was to evaluate Carbon sequestration potentiality under three mineral N fertilization levels in interaction with two cropping systems characterized by addition of N input due to leguminous species in the rotation. The study was carried out in the semiarid Mediterranean environment in a 18years long-term experiment. Is well know that in the semiarid environment the excess of N fertilization reduces biomass yield and the consequent C input. On the contrary, both N and C input determine high difference in C/N input ratio and faster organic matter mineralization. Results showed no influence of N fertilization on SOC sequestration and a reduction of SOC stock due to crop rotation due to lower C input. Crop residue quality of durum wheat-pea crop rotation characterized by a faster decomposition rate could explain the lower ability of crop rotation to sequester C in the semiarid environment.

  8. Tillage and crop rotation effects on soil quality in two Iowa fields

    Science.gov (United States)

    Soil quality is affected by inherent (parent material, climate, and topography) and anthropogenic (tillage and crop rotation) factors. We evaluated effects of five tillage treatments on 23 potential soil quality indicators after 31 years in a corn (Zea mays L.)/soybean [Glycine max (L.) Merr.] rotat...

  9. Does nitrogen fertilizer application rate to corn affect nitrous oxide emissions from the rotated soybean crop?

    Science.gov (United States)

    Iqbal, Javed; Mitchell, David C; Barker, Daniel W; Miguez, Fernando; Sawyer, John E; Pantoja, Jose; Castellano, Michael J

    2015-05-01

    Little information exists on the potential for N fertilizer application to corn ( L.) to affect NO emissions during subsequent unfertilized crops in a rotation. To determine if N fertilizer application to corn affects NO emissions during subsequent crops in rotation, we measured NO emissions for 3 yr (2011-2013) in an Iowa, corn-soybean [ (L.) Merr.] rotation with three N fertilizer rates applied to corn (0 kg N ha, the recommended rate of 135 kg N ha, and a high rate of 225 kg N ha); soybean received no N fertilizer. We further investigated the potential for a winter cereal rye ( L.) cover crop to interact with N fertilizer rate to affect NO emissions from both crops. The cover crop did not consistently affect NO emissions. Across all years and irrespective of cover crop, N fertilizer application above the recommended rate resulted in a 16% increase in mean NO flux rate during the corn phase of the rotation. In 2 of the 3 yr, N fertilizer application to corn (0-225 kg N ha) did not affect mean NO flux rates from the subsequent unfertilized soybean crop. However, in 1 yr after a drought, mean NO flux rates from the soybean crops that received 135 and 225 kg N ha N application in the corn year were 35 and 70% higher than those from the soybean crop that received no N application in the corn year. Our results are consistent with previous studies demonstrating that cover crop effects on NO emissions are not easily generalizable. When N fertilizer affects NO emissions during a subsequent unfertilized crop, it will be important to determine if total fertilizer-induced NO emissions are altered or only spread across a greater period of time.

  10. Increasing cropping system diversity balances productivity, profitability and environmental health.

    Science.gov (United States)

    Davis, Adam S; Hill, Jason D; Chase, Craig A; Johanns, Ann M; Liebman, Matt

    2012-01-01

    Balancing productivity, profitability, and environmental health is a key challenge for agricultural sustainability. Most crop production systems in the United States are characterized by low species and management diversity, high use of fossil energy and agrichemicals, and large negative impacts on the environment. We hypothesized that cropping system diversification would promote ecosystem services that would supplement, and eventually displace, synthetic external inputs used to maintain crop productivity. To test this, we conducted a field study from 2003-2011 in Iowa that included three contrasting systems varying in length of crop sequence and inputs. We compared a conventionally managed 2-yr rotation (maize-soybean) that received fertilizers and herbicides at rates comparable to those used on nearby farms with two more diverse cropping systems: a 3-yr rotation (maize-soybean-small grain + red clover) and a 4-yr rotation (maize-soybean-small grain + alfalfa-alfalfa) managed with lower synthetic N fertilizer and herbicide inputs and periodic applications of cattle manure. Grain yields, mass of harvested products, and profit in the more diverse systems were similar to, or greater than, those in the conventional system, despite reductions of agrichemical inputs. Weeds were suppressed effectively in all systems, but freshwater toxicity of the more diverse systems was two orders of magnitude lower than in the conventional system. Results of our study indicate that more diverse cropping systems can use small amounts of synthetic agrichemical inputs as powerful tools with which to tune, rather than drive, agroecosystem performance, while meeting or exceeding the performance of less diverse systems.

  11. Increasing cropping system diversity balances productivity, profitability and environmental health.

    Directory of Open Access Journals (Sweden)

    Adam S Davis

    Full Text Available Balancing productivity, profitability, and environmental health is a key challenge for agricultural sustainability. Most crop production systems in the United States are characterized by low species and management diversity, high use of fossil energy and agrichemicals, and large negative impacts on the environment. We hypothesized that cropping system diversification would promote ecosystem services that would supplement, and eventually displace, synthetic external inputs used to maintain crop productivity. To test this, we conducted a field study from 2003-2011 in Iowa that included three contrasting systems varying in length of crop sequence and inputs. We compared a conventionally managed 2-yr rotation (maize-soybean that received fertilizers and herbicides at rates comparable to those used on nearby farms with two more diverse cropping systems: a 3-yr rotation (maize-soybean-small grain + red clover and a 4-yr rotation (maize-soybean-small grain + alfalfa-alfalfa managed with lower synthetic N fertilizer and herbicide inputs and periodic applications of cattle manure. Grain yields, mass of harvested products, and profit in the more diverse systems were similar to, or greater than, those in the conventional system, despite reductions of agrichemical inputs. Weeds were suppressed effectively in all systems, but freshwater toxicity of the more diverse systems was two orders of magnitude lower than in the conventional system. Results of our study indicate that more diverse cropping systems can use small amounts of synthetic agrichemical inputs as powerful tools with which to tune, rather than drive, agroecosystem performance, while meeting or exceeding the performance of less diverse systems.

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

    Science.gov (United States)

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

    2015-04-01

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

  13. INFLUÊNCIA DO PREPARO DE SOLO E DA ROTAÇÃO DE CULTURAS NA SEVERIDADE DE PODRIDÕES RADICULARES NO FEIJOEIRO COMUM EFFECTS OF SOIL TILLAGE SYSTEM AND CROP ROTATION ON DRY BEAN ROOT ROT SEVERITY

    Directory of Open Access Journals (Sweden)

    Pedro Marques da Silveira

    2007-09-01

    Full Text Available

    As podridões radiculares do feijoeiro são causadas pelos fungos Rhizoctonia solani Kühn e Fusarium solani f. sp. phaseoli Snyd. & Hans. Neste trabalho testou-se a combinação dos fatores preparo de solo e rotação de culturas, além de se avaliarem seus efeitos sobre as podridões radiculares do feijoeiro. Os tipos de preparo de solo consistiram em: arado+grade (P1, arado (P2, grade (P3 e plantio direto (P4. As rotações de culturas foram: arroz-feijão (R1, milho-feijão (R2, arroz/calopogônio (Calopogonium muconoides-feijão (R3 e milho-feijão-milho-feijão-arroz-feijão (R4. A severidade de F. solani f. sp. phaseoli, avaliada aos 25 dias após o plantio, apresentou interação significativa, sendo a maior severidade encontrada na combinação da rotação R3 com o preparo de solo P1, e a menor severidade, na combinação da rotação R2 com o preparo de solo P3. Diferenças estatísticas ocorreram na severidade da doença provocada por R. solani. O preparo de solo P3 apresentou maior severidade que P4, e, entre as rotações, R3 apresentou a maior severidade da doença.

    PALAVRAS-CHAVE: Rhizoctonia solani; Fusarium solani f. sp. phaseoli; práticas culturais; fungos.

    Dry bean root rot is caused by the fungi Rhizoctonia solani Kühn and Fusarium solani f. sp. phaseoli Snyd. & Hans.The effects of the interaction between soil tillage systems andcrop rotation on the severity of root rot was tested. The soiltillage systems consisted of plough+harrow (P1, plough (P2,harrow (P3 and no tillage (P4 and the crop rotation treatmentswere rice-bean (R1, corn-bean (R2, rice/Calopogonium muconoides-bean (R3 and corn

  14. Effects of crop rotation and soil tillage on weeds in organic farming

    Directory of Open Access Journals (Sweden)

    Schulz, Franz

    2014-02-01

    Full Text Available An organic long-term field experiment with two factors has been carried out since 1998 at the experimental station Gladbacherhof, University of Giessen. Effects of 3 different farm types (with lifestock raising, stockless farming with rotational set-aside, stockless farming only cash crops combined with 4 tillage treatments (mouldboard plough, two-layer-plough, reduced tillage depth and tillage without plough on plants, soil and environment have been investigated. This article presents results on the coverage rate of arable wild plants (weed coverage, the range of weed species, the abundance of C. arvense (L. Scop. (Canada thistle and the weed phytomass during harvest time of the main crops dependent on farm type and soil tillage. It can be concluded that, compared to conventional economic weed thresholds, the weed coverage was generally relatively low and only limited ranges of species were found. Wild arable plants probably did not have any impact on yields of the cultivated plants due to intensive mechanical regulatory measures. In stockless organic farming without alfalfa-grass in the crop rotation Cirsium arvense (L. Scop. (Canada thistle might become a problem whereas this perennial root-weed does not seem to raise a long term problem in a soil tillage system without ploughing. In all treatments the abundance of weeds like Galium aparine L. (catchweed bedstraw and Stellaria media L. (chickweed was high. However, none of the farm types or soil tillage systems succeeded in providing evidence of promoting rare species or encouraging biodiversity. In order to achieve this special support measures should be implemented.

  15. Comparison of Crop Rotation for Verticillium Wilt Management and Effect on Pythium Species in Conventional and Organic Strawberry Production

    OpenAIRE

    Subbarao, Krishna V.

    2009-01-01

    The effects of broccoli and lettuce rotations on population densities of Verticillium dahliae and Pythium spp. in soil and on strawberry (Fragaria × ananassa) growth, yield, and Verticillium wilt were evaluated in conventional and organic production systems in California for 2 years. Under both management systems, strawberry was planted after two successive crops of broccoli or lettuce. The control treatment in the conventional field was strawberry planted in soils fumigated with methyl bromi...

  16. Energy balance of five fodder cropping systems in the irrigated lowlands of Northern Italy

    Directory of Open Access Journals (Sweden)

    Cesare Tomasoni

    2011-03-01

    Full Text Available Extensification has recently become an important option in Western European agriculture, driven both by economic considerations (product surpluses together with the fact that developed countries cropping systems have been heavily relying on fossil energy and growing public concern on the possible adverse effects of intensive farming on the environment and human health. The adoption of rational fodder crop rotations, with the rediscovery of the beneficial effect of the meadow, is viewed as a possible mean to reduce the impact of farming systems in the lowlands of Northern Italy, characterised by highly intensive cropping and animal husbandry. For this reason our study examines the effects of crop rotation on the energy balance during 1985-2007 period in a long-term crop rotation trial in Northern Italy comparing five fodder crop systems, different in the degree of crop intensification and for the presence or absence of the meadow: a 1-year continuous cereal double cropping (R1; a 3-year rotation (R3; a 6-year rotation (R6; a permanent meadow (PM; and a continuous grain maize cropping (CM. Each rotation was subjected to two input treatments, defined as high (mostly used in lowlands of northern Italy and low (input reduction of ca. 30% respectively, in terms of nutrient levels, herbicide doses, and soil tillage methods. The crop rotations exerted a marked influence on the energy balance. The most efficient rotations in terms of net energy production energy efficiency have been characterized by reduced length and presence of maize and catch-crops.

  17. Effectiveness of Growing the Sugar Buckwheat in Short Time Crop Rotation

    Directory of Open Access Journals (Sweden)

    Asker U. Taychibekov

    2012-09-01

    Full Text Available If you fertilize the sugar buckwheat by organ minerals on a one-time basic as a first harvest in 3-fiels short time crop rotation, it positively effects the productivity of 1st, 2nd an 3rd crops. Thus the highest rates of productivity have been observed by dung application 60 t/ha and NPK + dung 60 t/ha.

  18. Crop rotation-dependent yield responses to fertilization in winter oilseed rape (Brassica napus L.

    Directory of Open Access Journals (Sweden)

    Tao Ren

    2015-10-01

    Full Text Available Differences in soil physical, chemical and biological properties between paddy–upland and continuous upland rotations will influence nutrient relations and crop growth. With the aim of estimating rapeseed yield performance in response to fertilization in rice–rapeseed (RR and cotton–rapeseed (CR rotations, on-farm experiments were conducted at 70 sites across Hubei province, central China. The economically optimal fertilizer rates of winter oilseed rape in different rotations were determined. Field experiments showed that previous crops significantly influenced seed yields. Without N fertilization, seed yields were significantly lower for the RR rotation than for the CR rotation. The average yield increase ratio and agronomic efficiency associated with nitrogen (N fertilization in the RR rotation were 96.6% and 6.56 kg kg− 1, significantly higher than those in the CR rotation. No seed yield differences were detected between the two rotations under phosphorus (P and potassium (K fertilization. In contrast to the CR rotation, N fertilizer played a more vital role in maintaining high seed yields in the RR rotation owing to the lower indigenous soil N supply. Compared with local N fertilizer recommendation rates for the RR rotation, on average an additional 18 kg N ha− 1 was recommended according to the economically optimal N fertilizer rate (EONFR. In contrast, the EONFR was 14 kg N ha− 1 lower than the locally recommended N fertilizer rate for the CR rotation. There were no differences between the two rotations for the average economically optimal P and K fertilization rates. Consequently, the average EONFR of winter oilseed rape could be reduced if cotton rather than rice preceded the winter oilseed rape.

  19. Crop rotation-dependent yield responses to fertilization in winter oilseed rape(Brassica napus L.)

    Institute of Scientific and Technical Information of China (English)

    Tao; Ren; Hui; Li; Jianwei; Lu; Rongyan; Bu; Xiaokun; Li; Rihuan; Cong; Mingxing; Lu

    2015-01-01

    Differences in soil physical, chemical and biological properties between paddy–upland and continuous upland rotations will influence nutrient relations and crop growth. With the aim of estimating rapeseed yield performance in response to fertilization in rice–rapeseed(RR) and cotton–rapeseed(CR) rotations, on-farm experiments were conducted at 70 sites across Hubei province, central China. The economically optimal fertilizer rates of winter oilseed rape in different rotations were determined. Field experiments showed that previous crops significantly influenced seed yields. Without N fertilization,seed yields were significantly lower for the RR rotation than for the CR rotation. The average yield increase ratio and agronomic efficiency associated with nitrogen(N)fertilization in the RR rotation were 96.6% and 6.56 kg kg- 1, significantly higher than those in the CR rotation. No seed yield differences were detected between the two rotations under phosphorus(P) and potassium(K) fertilization. In contrast to the CR rotation, N fertilizer played a more vital role in maintaining high seed yields in the RR rotation owing to the lower indigenous soil N supply. Compared with local N fertilizer recommendation rates for the RR rotation, on average an additional 18 kg N ha- 1was recommended according to the economically optimal N fertilizer rate(EONFR). In contrast, the EONFR was 14 kg N ha- 1lower than the locally recommended N fertilizer rate for the CR rotation. There were no differences between the two rotations for the average economically optimal P and K fertilization rates. Consequently, the average EONFR of winter oilseed rape could be reduced if cotton rather than rice preceded the winter oilseed rape.

  20. Crop rotation-dependent yield responses to fertilization in winter oilseed rape (Brassica napus L.)

    Institute of Scientific and Technical Information of China (English)

    Tao Ren; Hui Li; Jianwei Lu; Rongyan Bu; Xiaokun Li; Rihuan Cong; Mingxing Lu

    2015-01-01

    Differences in soil physical, chemical and biological properties between paddy–upland and continuous upland rotations will influence nutrient relations and crop growth. With the aim of estimating rapeseed yield performance in response to fertilization in rice–rapeseed (RR) and cotton–rapeseed (CR) rotations, on-farm experiments were conducted at 70 sites across Hubei province, central China. The economically optimal fertilizer rates of winter oilseed rape in different rotations were determined. Field experiments showed that previous crops significantly influenced seed yields. Without N fertilization, seed yields were significantly lower for the RR rotation than for the CR rotation. The average yield increase ratio and agronomic efficiency associated with nitrogen (N) fertilization in the RR rotation were 96.6% and 6.56 kg kg−1, significantly higher than those in the CR rotation. No seed yield differences were detected between the two rotations under phosphorus (P) and potassium (K) fertilization. In contrast to the CR rotation, N fertilizer played a more vital role in maintaining high seed yields in the RR rotation owing to the lower indigenous soil N supply. Compared with local N fertilizer recommendation rates for the RR rotation, on average an additional 18 kg N ha−1 was recommended according to the economically optimal N fertilizer rate (EONFR). In contrast, the EONFR was 14 kg N ha−1 lower than the locally recommended N fertilizer rate for the CR rotation. There were no differences between the two rotations for the average economically optimal P and K fertilization rates. Consequently, the average EONFR of winter oilseed rape could be reduced if cotton rather than rice preceded the winter oilseed rape.

  1. Dinâmica e contribuição da micorriza arbuscular em sistemas de produção com rotação de culturas Dynamics and contribution of arbuscular mycorrhiza in culture systems with crop rotation

    Directory of Open Access Journals (Sweden)

    Jeanne Christine Claessen de Miranda

    2005-10-01

    Full Text Available Rotação de culturas e variações sazonais podem promover alterações quantitativas e qualitativas na comunidade de fungos micorrízicos arbusculares nativos e na formação da micorriza arbuscular. Essa dinâmica foi avaliada, em campo, num Latossolo Vermelho, em relação ao tempo de cultivo e variação sazonal, em sistemas de rotação de culturas. Em casa de vegetação, avaliou-se, em solo proveniente da área experimental, a contribuição da micorriza arbuscular no crescimento de soja e capim-andropógon utilizados na rotação. O número de esporos dos fungos aumentou no solo cultivado. O número de esporos e o porcentual de colonização radicular, inicialmente maiores sob pastagem, variaram de acordo com o tempo de cultivo, as estações seca e chuvosa, a cultura e o sistema de rotação utilizados. O número de gêneros e espécies aumentou com o tempo de cultivo e manejo de culturas e foi maior sob culturas anuais em rotação. A presença dos fungos no solo contribuiu no crescimento da soja e do capim-andropógon em 53% e 95%, respectivamente. A cultura e o sistema de cultivo são fatores determinantes para o enriquecimento do sistema com micorriza arbuscular.Crop rotation and seasonal variations can promote quantitative and qualitative changes in the indigenous arbuscular mycorrhizal fungi population in the soil and arbuscular mycorrhiza establishment. These fungi dynamics were evaluated in the field, in a Red Latosol, in relation to cropping time, seasonal variation and rotation systems. The contribution of arbuscular mycorrhiza to the growth of andropogon grass and soybean, which were used in the systems, was evaluated in a greenhouse experiment using soil from the experimental area. The number of spores of the fungi increased in the cultivated soil. The spores number and percent root colonization varied according to cropping time, soil moisture, crops and rotation system and were, initially, higher under pasture. The number

  2. Mineral nitrogen in the course of a cash crop and two livestock rotations - first results from the long-term monitoring Trenthorst

    OpenAIRE

    2008-01-01

    The long-term monitoring Trenthorst, situated near Lübeck in a temperate maritime climate on loamy soils, was established in 2003 and compares two cash crop and three livestock farming systems. We studied the soil mineral nitrogen contents of one cash crop and two livestock farms, specialised in dairy cows and goats/oilseeds resp., with the hypothesis that the livestock farms show a more even course of Nmin in the rotation and a higher rotation mean. The rotation average of Nmin in the cash c...

  3. Soil enzyme activities under long-term tillage and crop rotation systems in subtropical agro-ecosystems Atividade enzimática em solo sob plantio direto e rotações de culturas em agro-ecossistema subtropical

    Directory of Open Access Journals (Sweden)

    Elcio Liborio Balota

    2004-12-01

    Full Text Available Agricultural practices that reduce soil degradation and improve agricultural sustainability are needed particularly for tropical/subtropical soils. No-tillage planting causes minimal soil disturbance and combined with crop rotation may hold potential to meet these goals. Soil enzyme activities can provide information on how soil management is affecting the potential to perform the processes in soils such as decomposition and nutrient cycling. Soil enzyme activities were investigated in a split-plot experiment (3 replications where tillage (no till and conventional was the main plot and crop rotation (soybean/wheat, S/W; maize/wheat, M/W or cotton/wheat, C/W was the subplot. The experiment was established in 1976 in southern Brazil. Soil samples were taken at 0-5, 5-10 and 10-20 cm depths in 1997 and 1998. The 0-5 cm layer under NT system showed increases up 68% for amylase, 90% for cellulase, 219% for arylsulfatase, 46% for acid phosphatase, and 61% for alkaline phosphatase. There were significant correlations of soil enzyme activities with total organic C, and C and N microbial biomass. These results showed that NT increased microbial activity and that soil enzyme activity is a sensitive indicator of alteration soil quality by management.Práticas agrícolas que reduzam a degradação do solo e promovam sustentabilidade são importantes para os agrossistemas tropicais/subtropicais. O plantio direto (PD diminui as perdas de solo e, se combinado com rotação de culturas pode proteger o solo da degradação físico-química provocada pela agricultura intensiva. A atividade enzimática do solo pode fornecer importantes informações de como o manejo do solo está afetando a decomposição da material orgânica e a ciclagem dos nutrientes. Assim, avaliou-se a atividade das enzimas amilase, celulose, arilsulfatase, fosfatase ácida e fosfatase alcalina em um experimento a campo, instalado em 1976 em Londrina, PR, que tem como tratamentos o preparo

  4. Soil greenhouse gas emissions affected by irrigation, tillage, crop rotation, and nitrogen fertilization.

    Science.gov (United States)

    Sainju, Upendra M; Stevens, William B; Caesar-Tonthat, Thecan; Liebig, Mark A

    2012-01-01

    Management practices, such as irrigation, tillage, cropping system, and N fertilization, may influence soil greenhouse gas (GHG) emissions. We quantified the effects of irrigation, tillage, crop rotation, and N fertilization on soil CO, NO, and CH emissions from March to November, 2008 to 2011 in a Lihen sandy loam in western North Dakota. Treatments were two irrigation practices (irrigated and nonirrigated) and five cropping systems (conventional-tilled malt barley [ L.] with N fertilizer [CT-N], conventional-tilled malt barley with no N fertilizer [CT-C], no-tilled malt barley-pea [ L.] with N fertilizer [NT-PN], no-tilled malt barley with N fertilizer [NT-N], and no-tilled malt barley with no N fertilizer [NT-C]). The GHG fluxes varied with date of sampling and peaked immediately after precipitation, irrigation, and/or N fertilization events during increased soil temperature. Both CO and NO fluxes were greater in CT-N under the irrigated condition, but CH uptake was greater in NT-PN under the nonirrigated condition than in other treatments. Although tillage and N fertilization increased CO and NO fluxes by 8 to 30%, N fertilization and monocropping reduced CH uptake by 39 to 40%. The NT-PN, regardless of irrigation, might mitigate GHG emissions by reducing CO and NO emissions and increasing CH uptake relative to other treatments. To account for global warming potential for such a practice, information on productions associated with CO emissions along with NO and CH fluxes is needed.

  5. Nitrous oxide emissions from crop rotations including wheat, rapeseed and dry pea

    Directory of Open Access Journals (Sweden)

    M. H. Jeuffroy

    2012-07-01

    Full Text Available Approximately 65% of anthropogenic emissions of N2O, a potent greenhouse gas, originate from soils at global scale, and particularly after N fertilisation of the main crops in Europe. Thanks to their capacity to fix atmospheric N2 through biological fixation, legumes allow to reduce N fertilizer use, and possibly N2O emission. Nevertheless, the decomposition of crop organic matter during the crop cycle and during the residue decomposition, and possibly the N fixation process itself, could lead to N2O emissions. The objective of this study was to quantify N2O emissions from a dry pea crop (Pisum sativum, harvested at maturity and from the subsequent crops in comparison with N2O emissions from wheat and oilseed-rape crops, fertilized or not, in various rotations. A field experiment was conducted during 4 consecutive years, aiming at comparing the emissions during the pea crop, in comparison with those during the wheat (fertilized or not or oilseed rape crops, and after the pea crop, in comparison with other preceding crops. N2O fluxes were measured using static chambers. In spite of low N2O fluxes, mainly linked with the site soil characteristics, fluxes during the crop were significantly lower for pea and unfertilized wheat than for fertilized wheat and oilseed rape. The effect of the preceding crop was not significant, while soil mineral N at harvest was higher after pea. These results, combined with the emission reduction allowed by the production and transport of the N fertiliser not applied on the pea crop, should be confirmed in a larger range of soil types. Nevertheless, they demonstrate the absence of N2O emission linked to the symbiotic N fixation process, and allow us to estimate the decrease of N2O emissions to 20–25% by including one pea crop in a three-year rotation. At a larger scale, this reduction of GHG emissions

  6. Nitrous oxide emissions from crop rotations including wheat, rapeseed and dry pea

    Science.gov (United States)

    Jeuffroy, M. H.; Baranger, E.; Carrouée, B.; de Chezelles, E.; Gosme, M.; Hénault, C.; Schneider, A.; Cellier, P.

    2012-07-01

    Approximately 65% of anthropogenic emissions of N2O, a potent greenhouse gas, originate from soils at global scale, and particularly after N fertilisation of the main crops in Europe. Thanks to their capacity to fix atmospheric N2 through biological fixation, legumes allow to reduce N fertilizer use, and possibly N2O emission. Nevertheless, the decomposition of crop organic matter during the crop cycle and during the residue decomposition, and possibly the N fixation process itself, could lead to N2O emissions. The objective of this study was to quantify N2O emissions from a dry pea crop (Pisum sativum, harvested at maturity) and from the subsequent crops in comparison with N2O emissions from wheat and oilseed-rape crops, fertilized or not, in various rotations. A field experiment was conducted during 4 consecutive years, aiming at comparing the emissions during the pea crop, in comparison with those during the wheat (fertilized or not) or oilseed rape crops, and after the pea crop, in comparison with other preceding crops. N2O fluxes were measured using static chambers. In spite of low N2O fluxes, mainly linked with the site soil characteristics, fluxes during the crop were significantly lower for pea and unfertilized wheat than for fertilized wheat and oilseed rape. The effect of the preceding crop was not significant, while soil mineral N at harvest was higher after pea. These results, combined with the emission reduction allowed by the production and transport of the N fertiliser not applied on the pea crop, should be confirmed in a larger range of soil types. Nevertheless, they demonstrate the absence of N2O emission linked to the symbiotic N fixation process, and allow us to estimate the decrease of N2O emissions to 20-25% by including one pea crop in a three-year rotation. At a larger scale, this reduction of GHG emissions at field level has to be cumulated with the reduction of GHG emissions linked with the lower level of production and transport of the N

  7. Rotational woodlot technology in northwestern Tanzania. Tree species and crop performance

    NARCIS (Netherlands)

    Nyadzi, G.I.; Otsyina, R.M.; Banzi, F.M.; Bakengesa, S.S.; Gama, B.M.; Mbwambo, L.; Asenga, D.

    2003-01-01

    Growing of trees as woodlots on farms for five to seven years in rotation with crops was considered as a potential technology to overcome the shortage of wood, which is a common problem to many parts of sub-Saharan Africa. The paper summarizes the results of trials conducted at Tabora and Shinyanga

  8. Soil C sequestration and agronomic yield of diverse crop rotations under no-till soil management

    Science.gov (United States)

    Diversified crop rotations, which reduce risk associated with adoption of no-till soil management, may influence soil C sequestration and soil quality. This study measured effects of corn-soybean (C-S), corn-soybean-oat/pea hay (C-S-H), or corn-soybean-oat/pea hay-alfalfa-alfalfa (C-S-H-A-A) annual ...

  9. Faraday rotation system. Topical report

    Energy Technology Data Exchange (ETDEWEB)

    Bauman, L.E.; Wang, W.

    1994-07-01

    The Faraday Rotation System (FRS) is one of the advanced laser-based diagnostics developed at DIAL to provide support for the demonstration of prototype-scale coal-fired combustion magnetohydrodynamic (MHD) electrical power generation. Intended for application in the MHD channel, the system directly measures electron density through a measurement of the induced rotation in the polarization of a far infrared laser beam after passing through the MHD flow along the magnetic field lines. A measurement of the induced polarization ellipticity provides a measure of the electron collision frequency which together with the electron density gives the electron conductivity, a crucial parameter for MHD channel performance. The theory of the measurements, a description of the system, its capabilities, laboratory demonstration measurements on seeded flames with comparison to emission absorption measurements, and the current status of the system are presented in this final report.

  10. Least limiting water range in soil under crop rotations and chiseling

    Directory of Open Access Journals (Sweden)

    Juliano Carlos Calonego

    2011-06-01

    Full Text Available Soil water availability to plants is affected by soil compaction and other variables. The Least Limiting Water Range (LLWR comprises soil physical variables affecting root growth and soil water availability, and can be managed by either mechanical or biological methods. There is evidence that effects of crop rotations could last longer than chiseling, so the objective of this study was to assess the effect of soil chiseling or growing cover crops under no-till (NT on the LLWR. Crop rotations involving triticale (X Triticosecale and sunflower (Helianthus annuus in the fall-winter associated with millet (Pennisetum glaucum, sorghum (Sorghum bicolor and sunn hemp (Crotalaria juncea as cover crops preceding soybean (Glycine max were repeated for three consecutive years. In the treatment with chiseling (performed only in the first year, the area was left fallow between the fall-winter and summer crops. The experiment was carried out in Botucatu, São Paulo State, Brazil, from 2003 to 2006 on a Typic Rhodudalf. The LLWR was determined in soil samples taken from the layers 0-20 cm and 20- 40 cm, after chemical desiccation of the cover crops in December of the first and third year of the experiment. Chiseling decreases soil bulk density in the 0-20 cm soil layer, increasing the LLWR magnitude by lowering the soil water content at which penetration resistance reaches 2.0 MPa; this effect is present up to the third year after chiseling and can reach to a depth of 0.40 m. Crop rotations involving sunflower + sunn hemp, triticale + millet and triticale + sunn hemp for three years prevented soil bulk density from exceeding the critical soil bulk density in the 0- 0.20 m layer. This effect was observed to a depth of 0.40 m after three years of chiseling under crop rotations involving forage sorghum. Hence, chiseling and some crop rotations under no tillage are effective in increasing soil quality assessed by the LLWR.

  11. European Perspectives on the Adoption of Nonchemical Weed Management in Reduced -Tillage Systems for Arable Crops

    DEFF Research Database (Denmark)

    Melander, Bo; Munier-Jolain, Nicolas; Charles, Raphaël

    2013-01-01

    tillage systems. European agriculture is asked to become less dependent on pesticides and promote crop protection programmes based on integrated pest management (IPM) principles. Conventional non-inversion tillage systems rely entirely on the availability of glyphosate products, and herbicide consumption...... is mostly higher as compared to plough-based cropping systems. Annual grass weeds and catchweed bedstraw often constitute the principal weed problems in non-inversion tillage systems and crop rotations concurrently have very high proportions of winter cereals. There is a need to redesign cropping systems...

  12. Sustainability of Switchgrass Cropping Systems

    Science.gov (United States)

    Switchgrass (Panicum virgatum L.) is a perennial C4 grass that is native to the eastern two thirds of temperate North America. It has been used for conservation purposes and as a pasture grass since the 1940’s. It is currently being developed as a cellulosic biomass energy crop because it can produ...

  13. Malt barley yield and quality affected by irrigation, tillage, crop rotation, and nitrogen fertilization

    Science.gov (United States)

    Little is known about the comparison of management practices on malt barley (Hordeum vulgare L.) yield and quality in irrigated and non-irrigated cropping systems. We evaluated the effects of irrigation, tillage, cropping system, and N fertilization on malt barley yield and quality in a sandy loam s...

  14. Effect of Rotation Crops on Heterodera glycines Population Density in a Greenhouse Screening Study

    Science.gov (United States)

    Warnke, S.A.; Chen, S.Y.; Wyse, D.L.; Johnson, G.A.; Porter, P.M.

    2006-01-01

    Crop rotation is a common means of reducing pathogen populations in soil. Several rotation crops have been shown to reduce soybean cyst nematode (Heterodera glycines) populations, but a comprehensive study of the optimal crops is needed. A greenhouse study was conducted to determine the effect of growth and decomposition of 46 crops on population density of H. glycines. Crops were sown in soil infested with H. glycines. Plants were maintained until 75 days after planting, when the soil was mixed, a sample of the soil removed to determine egg density, and shoots and roots chopped and mixed into the soil. After 56 days, soil samples were again taken for egg counts, and a susceptible soybean (‘Sturdy’) was planted in the soil as a bioassay to determine egg viability. Sunn hemp (Crotalaria juncea), forage pea (Pisum sativum), lab-lab bean (Lablab purpureus), Illinois bundleflower (Desman-thus illinoensis), and alfalfa (Medicago sativa) generally resulted in smaller egg population density in soil or number of cysts formed on soybean in the bioassay than the fallow control. Sunn hemp most consistently showed the lowest numbers of eggs and cysts. As a group, legumes resulted in lower egg population densities than monocots, Brassica species, and other dicots. PMID:19259545

  15. Impact of Crop Rotation on Pathotype and Genetic Structure of Phythophthora sojae in Fields

    Institute of Scientific and Technical Information of China (English)

    Zhao Li-ming; Li Shuang; Sui Zhe; Huang Jing; Chen Qiu-ming; Suo Bing; Ding Jun-jie; Liu Wei-ting; Wen Jing-zhi

    2016-01-01

    To estimate the impact of crop rotation on the pathotype and genetic structure ofPhythophthora sojae in fields, 372 isolates ofP. sojae were obtained from long-term localisation experimental fields in Heilongjiang Province of China. The hypocotyl inoculation method was used to characterize the virulence ofP. sojaeon 13 differential cultivars, and the amplified fragment length polymorphism (AFLP) technique was used to analyze difference in the genetic structure ofP. sojae. The results indicated that an abundant diversity of genetic structures and pathotypes ofP. sojae, a more uniform distribution of pathotypes and less dominance of pathotypes occurred in corn-soybean and wheat-soybean rotation fields than in a continuous soybean mono-cropping field. These findings suggested thatP. sojae did not easily become the dominant race in rotation fields, which maintain disease resistance in soybean varieties. Therefore, the results of this study suggested that Phytophthora stem and root rot of soybeans could be effectively controlled by rotating soybeans with non-host crops of corn and wheat.

  16. CropIrri: A Decision Support System for Crop Irrigation Management

    OpenAIRE

    Zhang, Yi; Feng, Liping

    2010-01-01

    International audience; A field crop irrigation management decision-making system (CropIrri) was developed based on the soil water balance model, crop phenology model, root growth model, crop water production function, and irrigation management model. The irrigation plan is made through predicating of soil water content in root zone and daily crop water requirement using historical and forecasting weather data, measured real time soil moisture data. CropIrri provided four decision modes of no...

  17. Climatic and management drivers of CO2 exchanges by a production crop: Analysis over three successive 4-year crop rotation cycles

    OpenAIRE

    Buysse, Pauline; Manise, Tanguy; De Ligne, Anne; Moureaux, Christine; Bodson, Bernard; Heinesch, Bernard; Aubinet, Marc

    2016-01-01

    Carbon dioxide (CO2) exchanges between crops and the atmosphere are influenced by both climatic and crop management drivers. The investigated crop, situated at the Lonzée Terrestrial Observatory (LTO, candidate ICOS site) in Belgium and managed for more than 70 years using conventional farming practices, was monitored over three complete sugar beet/winter wheat/potato/winter wheat rotation cycles from 2004 to 2016. Continuous eddy-covariance measurements and regular biomass samplings were per...

  18. Changes of Labile Organic Carbon Fractions in Soils Under Different Rotation Systems

    Institute of Scientific and Technical Information of China (English)

    NI Jin-Zhi; XU Jian-Ming; XIE Zheng-Miao; WANG De-Jian

    2004-01-01

    Soil labile (biologically active) organic carbon fractions under different crop rotation systems in Jiangsu Province, China, were investigated after 10 years of rotation. The rotation systems, including green manurerice-rice (GmRR), wheat-rice-rice (WRR), wheat-rice (WR) and wheat/corn intercrop-rice (WCR) rotations,were established on paddy soils using a randomized complete block design with three replicates. The total organic carbon (TOC), total nitrogen (TN) and water-soluble organic carbon (WSOC) in the soils under different systems were greater in the GmRR and WRR than in the WR and WCR rotation systems because the soils under triple cropping often received more crop residues than the soils under double cropping. Both the WSOC and the microbial biomass carbon (MBC) contents in the soils of the GmRR rotation system were significantly greater than those in the other crop rotation systems, which was due to the return of green manure to the fields of the GmRR rotation system. The results of a 13C nuclear magnetic resonance (13C-NMR) analysis indicated that the structural characteristics of soil WSOC were similar under the four crop rotation systems with carbohydrates and long-chain aliphatics being the major components. Correlation analysis showed that the content of the WSOC was positively correlated with that of the MBC (P <0.01),and all had significantly positive correlations with TOC and TN. The coefficients of variation (CVs) for WSOC and WSOC/TOC were greater than the other indices (e.g, MBC, TOC and TN), suggesting that WSOC in the soils was more sensitive to these rotation systems. The results above indicated that the soil amended with green manure could not only increase the usable C source for soil microorganisms, but could also enhance soil organic matter content; hence, rotation with green manure would be a good strategy for sustainable agriculture.

  19. [Effects of rotations and different green manure utilizations on crop yield and soil fertility].

    Science.gov (United States)

    Yao, Zhi-yuan; Wang, Zheng; Li, Jing; Yu, Chang-wei; Cao, Qun-hu; Cao, Wei-dong; Gao, Ya-jun

    2015-08-01

    A 4-year field experiment was conducted to investigate the influence of three rotation systems and three corresponding leguminous green manure (LGM) application methods on wheat yield and soil properties. The rotation patterns were summer fallow--winter wheat (SW), LGM-- winter wheat (LW) and LGM--spring maize--winter wheat (LMW). The three LGM application methods of LW included: early mulch, early incorporation and late incorporation while the three LGM application methods of LMW were: stalk mulch, stalk incorporation and stalk move-away. The results indicated that for LW, LGM consumed more soil water, thus the wheat yield was not stable. The nitrate storage in 0-200 cm soil after wheat harvest was significantly higher than that of the others, indicating an increasing risk of nitrate leaching. Early mulch under LW had the highest soil organic carbon (SOC) content and storage of SOC (SSOC) in 0-20 cm soil. For LMW, wheat yield was comparatively stable among years, because of higher water storage before wheat seeding, and the nitrate storage in 0-200 cm soil after wheat harvest was significantly lower than LW, which decreased the risk of nitrate leaching. Stalk mulch had higher SOC content in 0-20 cm soil after wheat harvest compared with move-away. In addition, compared with the soil when the experiment started, stalk much also increased SSOC in 0-20 cm soil. In conclusion, LMW with stalk mulch could increase soil water storage, stabilize crop yield, improve soil fertility and decrease 0-200 cm soil nitrate storage. This system could be treated as a good alternative for areas with similar climate.

  20. Volatile organic compound emissions from Miscanthus and short rotation coppice willow bioenergy crops

    Science.gov (United States)

    Copeland, Nichola; Cape, J. Neil; Heal, Mathew R.

    2012-12-01

    Miscanthus × giganteus and short rotation coppice (SRC) willow (Salix spp.) are increasingly important bioenergy crops. Above-canopy fluxes and mixing ratios of volatile organic compounds (VOCs) were measured in summer for the two crops at a site near Lincoln, UK, by proton transfer reaction mass spectrometry (PTR-MS) and virtual disjunct eddy covariance. The isoprene emission rate above willow peaked around midday at ˜1 mg m-2 h-1, equivalent to 20 μg gdw-1 h-1 normalised to 30 °C and 1000 μmol m-2 s-1 PAR, much greater than for conventional arable crops. Average midday peak isoprene mixing ratio was ˜1.4 ppbv. Acetone and acetic acid also showed small positive daytime fluxes. No measurable fluxes of VOCs were detected above the Miscanthus canopy. Differing isoprene emission rates between different bioenergy crops, and the crops or vegetation cover they may replace, means the impact on regional air quality should be taken into consideration in bioenergy crop selection.

  1. Soil respiration in cucumber field under crop rotation in solar greenhouse

    Directory of Open Access Journals (Sweden)

    Yinli Liang

    2014-08-01

    Full Text Available Crop residues are the primary source of carbon input in the soil carbon pool. Crop rotation can impact the plant biomass returned to the soil, and influence soil respiration. To study the effect of previous crops on soil respiration in cucumber (Cucumis statirus L. fields in solar greenhouses, soil respiration, plant height, leaf area and yield were measured during the growing season (from the end of Sept to the beginning of Jun the following year from 2007 to 2010. The cucumber was grown following fallow (CK, kidney bean (KB, cowpea (CP, maize for green manure (MGM, black bean for green manure (BGM, tomato (TM, bok choy (BC. As compared with CK, KB, CP, MGM and BGM may increase soil respiration, while TM and BC may decrease soil respiration at full fruit stage in cucumber fields. Thus attention to the previous crop arrangement is a possible way of mitigating soil respiration in vegetable fields. Plant height, leaf area and yield had similar variation trends under seven previous crop treatments. The ratio of yield to soil respiration revealed that MGM is the crop of choice previous to cucumber when compared with CK, KB, CP, BGM, TM and BC.

  2. The Effects of Winter Cover Crops and Plant Growth Promoting Rhizobacteria on some Soil Fertility Aspects and Crop Yield in an Organic Production System of Ocimum basilicum L.

    OpenAIRE

    M. Jahan; M.B Amiri; J Shabahang; Ahmadi, F; F. Soleymani

    2014-01-01

    Sustainable agriculture systems emphasized on the on-farm inputs likes use of biofertilizers, crop rotation and cover crops. This experiment was conducted in a split plots arrangement with two factors based on randomized complete block design with three replications during years 2009-2010, at Research Farm of Ferdowsi University of Mashhad. The main factor consisted of cultivation and no cultivation of cover crops in autumn. The sub factor was biofertilizer application with four levels, inclu...

  3. Study on Soil Denitrification in Wheat-Maize Rotation System

    Institute of Scientific and Technical Information of China (English)

    ZOU Guo-yuan; ZHANG Fu-suo; JU Xiao-tang; CHEN Xin-ping; LIU Xue-jun

    2006-01-01

    Soil denitrification was studied in wheat-maize rotation cropping system on an aquic cambisol. Results showed that the N loss amount by denitrification ranged from 4.7 to 9.7 kg per hectare with different levels of nitrogen application and the key stage for denitification was during summer maize-growth-period, especially within 1-2 weeks after fertilizer nitrogen was applied. Similar trend was found between soil N2O production/emission dynamic and denitrification dynamic in the rotation system, which may indicate that mainly N2O is produced in nitrification process.

  4. Rotational Electromagnetic Energy Harvesting System

    Science.gov (United States)

    Dinulovic, Dragan; Brooks, Michael; Haug, Martin; Petrovic, Tomislav

    This paper presents development of the rotational electromagnetic energy harvesting transducer. The transducer is driven mechanically by pushing a button; therefore, the mechanical energy will be converted into electrical energy. The energy harvesting (EH) transducer consists of multilayer planar coils embedded in a PCB, multipolar NdFeB hard magnets, and a mechanical system for movement conversion. The EH transducer generate an energy of about 4 mJ at a load of 10 Ω. The maximum open circuit output voltage is as high as 2 V and the maximum short circuit output current is 800 mA.

  5. Grassland carbon sequestration and emissions following cultivation in a mixed crop rotation

    DEFF Research Database (Denmark)

    Acharya, Bharat Sharma; Rasmussen, Jim; Eriksen, Jørgen

    2012-01-01

    Grasslands are potential carbon sinks to reduce unprecedented increase in atmospheric CO2. Effect of age (1–4-year-old) and management (slurry, grazing multispecies mixture) of a grass phase mixed crop rotation on carbon sequestration and emissions upon cultivation was compared with 17-year...... with age but indifference in CO2 emissions across the age and management in temporary grasslands, thus, indicates potential for long-term sequestration of soil C....

  6. Short-rotation woody-crops program. Quarterly progress report for period ending August 31, 1981

    Energy Technology Data Exchange (ETDEWEB)

    Cushman, J.H.; Ranney, J.W.

    1982-04-01

    Progress of twenty-one projects in the Short Rotation Woody Crops Program is summarized for the period June 1 through August 31, 1981. Individual quarterly reports included from each of the projects discuss accomplishments within specific project objectives and identify recent papers and publications resulting from the research. The major program activities are species screening and genetic selection, stand establishment and cultural treatment, and harvest, collection, transportation, and storage.

  7. Short-rotation woody-crops program. Quarterly progress report for period ending May 31, 1981

    Energy Technology Data Exchange (ETDEWEB)

    Cushman, J.H.; Ranney, J.W.

    1982-04-01

    Progress of twenty projects in the Short Rotation Woody Crops Program is summarized for the period March 1 through May 31, 1981. Individual quarterly reports included from each of the projects discuss accomplishments within specific project objectives and identify recent papers and publications resulting from the research. The major project activities are species screening and genetic selection, stand establishment and cultural treatment, and harvest, collection, transportation, and storage.

  8. Tropical legume crop rotation and nitrogen fertilizer effects on agronomic and nitrogen efficiency of rice.

    Science.gov (United States)

    Rahman, Motior M; Islam, Aminul M; Azirun, Sofian M; Boyce, Amru N

    2014-01-01

    Bush bean, long bean, mung bean, and winged bean plants were grown with N fertilizer at rates of 0, 2, 4, and 6 g N m(-2) preceding rice planting. Concurrently, rice was grown with N fertilizer at rates of 0, 4, 8, and 12 g N m(-2). No chemical fertilizer was used in the 2nd year of crop to estimate the nitrogen agronomic efficiency (NAE), nitrogen recovery efficiency (NRE), N uptake, and rice yield when legume crops were grown in rotation with rice. Rice after winged bean grown with N at the rate of 4 g N m(-2) achieved significantly higher NRE, NAE, and N uptake in both years. Rice after winged bean grown without N fertilizer produced 13-23% higher grain yield than rice after fallow rotation with 8 g N m(-2). The results revealed that rice after winged bean without fertilizer and rice after long bean with N fertilizer at the rate of 4 g N m(-2) can produce rice yield equivalent to that of rice after fallow with N fertilizer at rates of 8 g N m(-2). The NAE, NRE, and harvest index values for rice after winged bean or other legume crop rotation indicated a positive response for rice production without deteriorating soil fertility.

  9. Long-term tillage and crop rotation effects on residual nitrate in the crop root zone and nitrate accumulation in the intermediate vadose zone

    Science.gov (United States)

    Katupitiya, A.; Eisenhauer, D.E.; Ferguson, R.B.; Spalding, R.F.; Roeth, F.W.; Bobier, M.W.

    1997-01-01

    Tillage influences the physical and biological environment of soil. Rotation of crops with a legume affects the soil N status. A furrow irrigated site was investigated for long-term tillage and crop rotation effects on leaching of nitrate from the root zone and accumulation in the intermediate vadose zone (IVZ). The investigated tillage systems were disk-plant (DP), ridge-till (RT) and slot-plant (SP). These tillage treatments have been maintained on the Hastings silt loam (Udic Argiustoll) and Crete silt loam (Pachic Argiustoll) soils since 1976. Continuous corn (CC) and corn soybean (CS) rotations were the subtreatments. Since 1984, soybeans have been grown in CS plots in even calendar years. All tillage treatments received the same N rate. The N rate varied annually depending on the root zone residual N. Soybeans were not fertilized with N-fertilizer. Samples for residual nitrate in the root zone were taken in 8 of the 15 year study while the IVZ was only sampled at the end of the study. In seven of eight years, root zone residual soil nitrate-N levels were greater with DP than RT and SP. Residual nitrate-N amounts were similar in RT and SP in all years. Despite high residual nitrate-N with DP and the same N application rate, crop yields were higher in RT and SP except when DP had an extremely high root zone nitrate level. By applying the same N rates on all tillage treatments, DP may have been fertilized in excess of crop need. Higher residual nitrate-N in DP was most likely due to a combination of increased mineralization with tillage and lower yield compared to RT and SP. Because of higher nitrate availability with DP, the potential for nitrate leaching from the root zone was greater with DP as compared to the RT and SP tillage systems. Spring residual nitrate-N contents of DP were larger than RT and SP in both crop rotations. Ridge till and SP systems had greater nitrate-N with CS than CC rotations. Nitrate accumulation in IVZ at the upstream end of the

  10. Effects of grass-clover management and cover crops on nitrogen cycling and nitrous oxide emissions in a stockless organic crop rotation

    DEFF Research Database (Denmark)

    Brozyna, Michal Adam; Petersen, Søren O; Chirinda, Ngoni

    2013-01-01

    little or no effect on N2O emissions. Periods of high N2O emissions coincided with cover crop and grass-clover residue turnover, with little added effect of digested manure application. Annual N2O emissions did not vary between fertilization treatments, but the +M treatment had cash crop dry matter...... and cash-crop yields in an organic arable crop rotation on a sandy loam soil in a cool temperate climate. The four-course crop rotation included spring barley (with undersown grass-clover), grass-clover, potato and winter wheat (with undersown cover crop). Two fertilization treatments were compared: “−M......” where plant material from grass-clover cuts was left in the field to decompose and no fertilizer or manure was applied to any crop in the rotation; and “+M” where plant material from grass-clover cuts was harvested and equivalent amounts of N in digested manure used for fertilization of cash crops...

  11. Screening the Resilience of Short-Rotation Woody Crops to Climate Change

    Directory of Open Access Journals (Sweden)

    Sophan Chhin

    2016-01-01

    Full Text Available Sustainable woody biofeedstock production systems require a reliable supply of woody biomass that could be affected by future climate change. However, there is limited understanding of the climatic sensitivity of short rotation woody crops, such as hybrid aspens. The general objective of this study is to identify climatically resilient hybrid aspen clones for woody biomass feedstock development. Specifically, tree-ring analysis methods (dendrochronology were used to quantify the influence of climate on stem growth rates of hybrid aspens by measuring year-to-year changes in tree-ring width from different cultivars of hybrid aspen and relating annual growth patterns with past instrumental climate records (i.e., temperature and moisture index. Tree-ring analysis was conducted on a full-sib progeny plantation of different cultivars of hybrid aspens (Populus × smithii derived from different geographical variants of aspen parents: trembling aspen (Populus tremuloides and bigtooth aspen (Populus grandidentata located on Michigan State University property in the Sandhill Research Area (42.7°N latitude; 84.5°W longitude. Overall, the hybrid aspen families examined in this study were more sensitive to moisture related stressors compared to a weaker or no response to temperature stressors. By the end of the 21st century (2071–2100, 11 out of the 18 hybrid aspen families will be vulnerable to future changes in moisture stress, while the remaining families were screened to be resilient to future changes in moisture stress.

  12. Sustainable Production of Japanese Eggplants in a Piedmont Soil in Rotation with Winter Cover Crops

    Directory of Open Access Journals (Sweden)

    Ahmed Elobeid

    2013-03-01

    Full Text Available Eggplant is a popular vegetable consumed all over the world. Cover cropping is an efficient way of recycling nutrients and reducing inorganic fertilizer requirements to maintain the sustainability of the soil without affecting productivity and profitability. Eggplants (Solanum melongena (Japanese varieties Hansel and Kamo were grown in a Piedmont soil with two main treatments, cover crop (CC and no cover crop (NC, and four sub-fertilizer treatments (T1: 0-0-0, T2: 56-28-112, T3: 84-56-168, and T4: 168-112-224 N-P-K kg/ha, using four replications. The Hansel variety eggplant yield was significantly higher than the Kamo variety. Eggplant yields from CC treatments for both varieties were significantly higher (p < 0.001 than the yields from NC treatments. No significant difference was observed in the yields between T1 and T2 treatments, but the yields from T3 were significantly higher than T1 and T2 and yields from T4 were significantly higher than T3 yields. N released through mineralization of cover crop mixture ranged from 13.33 g/kg at the beginning of the growing season and increased to 18.32 g/kg at the end of the growing season. These results suggest that Japanese eggplants can be successfully grown in the Piedmont area of North Carolina in rotation with cover crops for higher yields.

  13. The consequent influence of crop rotation and six-year-long spring barley monoculture on yields and weed infestation of white mustard and oats

    Directory of Open Access Journals (Sweden)

    Cezary Kwiatkowski

    2012-12-01

    Full Text Available The present study was conducted in the years 2007- 2008, after 6-year-long experiments in the cultivation of spring barley in a crop rotation system and in monoculture. The other experimental factor was the spring barley protection method. Intensive protection involved comprehensive treatment of barley (in-crop harrowing, seed dressing, application of herbicides, fungicides, a retardant and an insecticide. Extensive protection consisted only in in-crop harrowing, without the application of crop protection agents, except for seed dressing. The above mentioned factors formed the background for the study on the cultivation of white mustard and oats, as phytosanitary species, in successive years. In the test plants, no mineral fertilization and crop protection were applied. Such agricultural method enabled an objective assessment of the consequent effect of monoculture, crop rotation and crop treatments. A hypothesis was made that the cultivation of the phytosanitary plants in the stand after 6-year-long barley monoculture would allow obtaining the level of yields and weed infestation similar to those of the crop rotation treatments. It was also assumed that the cultivation of white mustard and oats would eliminate differences in plant productivity caused by the negative influence of extensive protection. It was proved that the cultivation of the phytosanitary plants eliminated the negative influence of monoculture on the level of their yields and weed infestation. However, the test plants did not compensate negative consequences of extensive protection. In spite of this, white mustard and oats effectively competed with weeds, and the number and weight of weeds in a crop canopy did not cause a dramatic decline in yields. In the test plant canopy, the following short-lived weeds were predominant: Chenopodium album, Galinsoga parviflora, Echinochloa crus-galli. The absence of herbicide application resulted in the compensation of perennial species

  14. Sustentabilidade de sistemas de rotação e sucessão de culturas em solos de várzea no Sul do Brasil Crop rotations sustainability and successions systems in tilled plain areas in Southern Brazil

    Directory of Open Access Journals (Sweden)

    Francisco de Jesus Vernetti Junior

    2009-09-01

    performed, and its sustainability inferred. Analyses of contrasts between the crop successions were accomplished too. The results provided the following conclusions: (a All crop succession which had maize participation had a higher index sustainability; (b the crops successions S1 [Cereals x soybean x rice(NT] and S4 [Turnip x soybean x rice(NT] had, respectively, the highest and the lowest sustainability among the ones with the soybean crop participation; (c S5 [Native grass x soybean x rice(CT] showed the lowest sustainability level, (d S8 [Species mixtures x corn x rice(NT] presented the best distribution and balance between the different classes of sustainability considered; (e S10 [Native grass x corn x rice(CT] has the worst performance, regarding the sustainability of the one's which included maize; (f the NT system gives greater sustainability to the crop succession.

  15. Evaluation of Millet and Rapeseed as Rotation or Green Manure Crops to Control Nematodes in Orchard Replant

    Science.gov (United States)

    Four annual crops, including Canadian forage pearl millet (Pennisetum glaucum) hybrid 101, velvetbean (Mucuna spp. ), rapeseed (Brassica napus) cv. Dwarf Essex, and buckwheat (Fagopyrum spp.), were evaluated as rotation or green manure crops for suppression of dagger (Xiphinema americanum) and lesio...

  16. Crop Rotation and Nematicides for Management of Mixed Populations of Meloidogyne spp. on Tobacco.

    Science.gov (United States)

    Fortnum, B A; Lewis, S A; Johnson, A W

    2001-12-01

    The effects of crop rotation and the nematicides 1,3-dichloropropene (1,3-D), ethoprop, and fenamiphos on the relative frequency of Meloidogyne incognita race 3, M. arenaria race 2, and M. javanica and tobacco yields on a sandy loam soil were determined. Cropping sequences altered the species composition and population densities of Meloidogyne spp. Meloidogyne arenaria and M. incognita predominated when cotton, corn, sorghum, or rye-fallow preceded tobacco. Meloidogyne javanica and M. arenaria predominated when tobacco preceded tobacco. Sorghum, cotton, corn, or rye-fallow preceding tobacco enhanced yields compared to tobacco preceding tobacco in plots containing mixtures of Meloidogyne species. Sorghum supported minimal reproduction of any Meloidogyne spp. Application of 1,3-D increased tobacco yields and reduced root galling when compared to untreated controls. Both fenamiphos and ethoprop treatments were less effective than 1,3-D in controlling Meloidogyne spp. or increasing yields. A rotation crop x nematicide interaction was not observed. In continuous tobacco, use of the M. incognita-resistant tobacco cv. Coker 176 increased tobacco yields when compared to the M. incognita-susceptible cv. Coker 319 when 1,3-D was not applied.

  17. Role of nematodes, nematicides, and crop rotation on the productivity and quality of potato, sweet potato, peanut, and grain sorghum.

    Science.gov (United States)

    Johnson, A W; Dowler, C C; Glaze, N C; Handoo, Z A

    1996-09-01

    The objective of this experiment was to determine the effects of fenamiphos 15G and short-cycle potato (PO)-sweet potato (SP) grown continuously and in rotation with peanut (PE)-grain sorghum (GS) on yield, crop quality, and mixed nematode population densities of Meloidogyne arenaria, M. hapla, M. incognita, and Mesocriconema ornatum. Greater root-gall indices and damage by M. hapla and M. incognita occurred on potato than other crops. Most crop yields were higher and root-gall indices lower from fenamiphos-treated plots than untreated plots. The total yield of potato in the PO-SP and PO-SP-PE-GS sequences increased from 1983 to 1985 in plots infested with M. hapla or M. arenaria and M. incognita in combination and decreased in 1986 to 1987 when root-knot nematode populations shifted to M. incognita. The total yields of sweet potato in the PO-SP-PE-GS sequence were similar in 1983 and 1985, and declined each year in the PO-SP sequence as a consequence of M. incognita population density increase in the soil. Yield of peanut from soil infested with M. hapla increased 82% in fenamiphos-treated plots compared to untreated plots. Fenamiphos treatment increased yield of grain sorghum from 5% to 45% over untreated controls. The declining yields of potato and sweet potato observed with both the PO-SP and PO-SP-PE-GS sequences indicate that these crop systems should not be used longer than 3 years in soil infested with M. incognita, M. arenaria, or M. hapla. Under these conditions, these two cropping systems promote a population shift in favor of M. incognita, which is more damaging to potato and sweet potato than M. arenaria and M. hapla.

  18. Soil microbial substrate properties and microbial community responses under irrigated organic and reduced-tillage crop and forage production systems.

    Science.gov (United States)

    Ghimire, Rajan; Norton, Jay B; Stahl, Peter D; Norton, Urszula

    2014-01-01

    Changes in soil microbiotic properties such as microbial biomass and community structure in response to alternative management systems are driven by microbial substrate quality and substrate utilization. We evaluated irrigated crop and forage production in two separate four-year experiments for differences in microbial substrate quality, microbial biomass and community structure, and microbial substrate utilization under conventional, organic, and reduced-tillage management systems. The six different management systems were imposed on fields previously under long-term, intensively tilled maize production. Soils under crop and forage production responded to conversion from monocropping to crop rotation, as well as to the three different management systems, but in different ways. Under crop production, four years of organic management resulted in the highest soil organic C (SOC) and microbial biomass concentrations, while under forage production, reduced-tillage management most effectively increased SOC and microbial biomass. There were significant increases in relative abundance of bacteria, fungi, and protozoa, with two- to 36-fold increases in biomarker phospholipid fatty acids (PLFAs). Under crop production, dissolved organic C (DOC) content was higher under organic management than under reduced-tillage and conventional management. Perennial legume crops and organic soil amendments in the organic crop rotation system apparently favored greater soil microbial substrate availability, as well as more microbial biomass compared with other management systems that had fewer legume crops in rotation and synthetic fertilizer applications. Among the forage production management systems with equivalent crop rotations, reduced-tillage management had higher microbial substrate availability and greater microbial biomass than other management systems. Combined crop rotation, tillage management, soil amendments, and legume crops in rotations considerably influenced soil

  19. Will breeding for nitrogen use efficient crops lead to nitrogen use efficient cropping systems?

    DEFF Research Database (Denmark)

    Dresbøll, Dorte Bodin; Thorup-Kristensen, Kristian

    2014-01-01

    The benefits of improving nitrogen use efficiency (NUE) in crops are typically studied through the performance of the individual crop. However, in order to increase yields in a sustainable way, improving NUE of the cropping systems must be the aim. We did a model simulation study to investigate how...... is analyzed for the whole cropping system. The environmental conditions, crop choices and management will all affect the fate of the N left in the soil, and whether this will contribute mainly to leaching loss or be used for production in later crops. As an example, increasing pre-crop fertilization was shown...... to affect the leaching after the following oilseed rape crop with up to 50 kg N ha-1 taken up before it was lost to the environment when pre-crop fertilization as well as root depth penetration rate was high. All in all, the simulations illustrate the concept of NUE as the result of interactions between...

  20. Environmental sustainability of cellulosic energy cropping systems

    Science.gov (United States)

    The environmental sustainability of bioenergy production depends on both direct and indirect effects of the production systems to produce bioenergy feedstocks. This chapter evaluates what is known about the environmental sustainability of cellulosic bioenergy crop production for the types of produc...

  1. Weed infestation of a cereal-legume mixture depending on its concentration and position in a crop rotation

    Directory of Open Access Journals (Sweden)

    Marta K. Kostrzewska

    2012-10-01

    Full Text Available A field study was carried out in the period 2000-2006 at the Experimental Station in Tomaszkowo belonging to the University of Warmia and Mazury in Olsztyn. Its aim was to compare weed infestation of a mixture of spring barley and field pea grown in a four crop rotation with different crop selection and sequence. Each year during tillering of spring barley and before the harvest of the mixture, weed species composition and density were evaluated, while additionally weed biomass was also estimated before the harvest. These results were used to determine species constancy, Simpson’s dominance index, the Shannon-Wiener diversity and evenness indices as well as the community similarity index based on floristic richness, numbers and biomass of particular weed species. The cropping frequency and the position of the mixture in the crop rotation did not differentiate the species composition and total biomass of weed communities in the cereal-legume mixture crops. The crop rotation in which the mixture constituted 50% and was grown after itself had a reducing effect on weed numbers. Growing field pea in the 4-year crop rotation promoted weed infestation of the mixture and the dominance of weed communities. Capsella bursa-pastoris, Chenopodium album, Echinochloa crus-galli, Elymus repens, Polygonum convolvulus, and Sonchus arvensis were constant components of the agrophytocenoses. The weed communities were more similar in terms of their floristic composition than in terms of weed density and air-dry weight of weeds.

  2. Energy partitioning and GPP values in a rotating crop in the Spanish Plateau

    Science.gov (United States)

    Sánchez, María Luisa; Pardo, Nuria; Perez, Isidro A.; Garcia, M. Angeles

    2016-04-01

    In order to assess crop ability to act as a CO2 sink and to describe GPP dynamic evolution, in 2008 we installed an eddy correlation station located in an agricultural plot of the Spanish plateau. Continuous measurements of 30-min NEE fluxes and other common variables have been measured over four years. Agricultural practices at the selected plot consisted of annual rotation of non-irrigated rapeseed, wheat, peas, rye. The maximum canopy height of rapeseed, wheat and rye was 1.3, 0.6 and 1.6 m respectively, the values being reached at the end of May. Although no measurements were performed in the pea crop, according to the farmer's information the maximum height was approximately 0.45-0.5 m. The quality of long-term eddy covariance data was evaluated by calculating the energy balance closure. This paper presents and compares the seasonal variation of major components involved in the energy balance as well as GPP for each type of crop. An energy balance closure of 92% was found when using the global dataset. On a four-year basis, the sensible heat flux, H, played the main role in the energy balance with a ratio of 52%. Latent heat flux, LE, accounted for 40% of the energy, with soil heat flux contributing around 8% to the energy balance. These values changed during the period of maximum interest. For this period LE played the main role, using over half of the available energy, 51%, related to evapotranspiration processes. Over the four years of study annual accumulated GPP exhibited a great variability, 1680, 710, 730 and 1410 g C m-2 for rapeseed, wheat, peas and rye, respectively. The influence of crop architecture, phenology and climatic conditions dominated crop-to-crop seasonal evolution. The highest LE contributions to the energy balance were found for rapeseed and rye. Higher GPP were also obtained for denser and higher canopy height crops, rapeseed and rye, yielding annuals almost comparable to C4 plants. Both crops exhibited a marked seasonal variation of

  3. Cooling system for rotating machine

    Science.gov (United States)

    Gerstler, William Dwight; El-Refaie, Ayman Mohamed Fawzi; Lokhandwalla, Murtuza; Alexander, James Pellegrino; Quirion, Owen Scott; Palafox, Pepe; Shen, Xiaochun; Salasoo, Lembit

    2011-08-09

    An electrical machine comprising a rotor is presented. The electrical machine includes the rotor disposed on a rotatable shaft and defining a plurality of radial protrusions extending from the shaft up to a periphery of the rotor. The radial protrusions having cavities define a fluid path. A stationary shaft is disposed concentrically within the rotatable shaft wherein an annular space is formed between the stationary and rotatable shaft. A plurality of magnetic segments is disposed on the radial protrusions and the fluid path from within the stationary shaft into the annular space and extending through the cavities within the radial protrusions.

  4. Determining the Appropriate Crop Rotation Plan in a Farm Scale Using Fuzzy Goal Programming Model

    Directory of Open Access Journals (Sweden)

    A. Alizadeh Zoeram

    2016-03-01

    Full Text Available Introduction One of the important subject in the field of agricultural programming is reaching to a pattern or appropriate crop rotation to plant. Existing constraints, including the amount of available resources, and different goals, makes the decision to optimize the use of resources and production factors a complicated task. Therefore, applying mathematical models can be a grate help in this field. The goal of this study is to determine the appropriate patterns of crop cultivation in a farm in the North Khorasan province. Materials and Methods Implem enting fuzzy goal programming (FGP model based on different scenarios was employed to achieve our goals. According to results ,represented process , constraints and problem goals, four plant patterns are offered based on eight proposed scenarios for crop products in this farm or this study. These proposed cultivation pattern can help to make better decision for determination the appropriate rotation of crops in different conditions and different goals by decision makers. Results Discussion Finally, proposed cultivation patterns were prioritized according to maximum amount of reaching the desired level of total goals. Based on maximum level of reaching goals, different scenarios consisted of income, cost, production resources, income-cost, income-production resources, cost-production resources, income-cost-production resources with equal weights, and income-cost-production resources with different weights have been prioritized and four cropping pattern have been detected. In first pattern, three scenario consisted of scenario 1 (income, scenario 4 (income-cost and scenario 5 (income-production resources have combined. The second pattern have made scenario 2 (cost. In third pattern, scenario 3 (production resources, scenario 6 (cost-production resources and scenario 7 (income-cost-production resources with equal weights have combined. The scenario 8 (income-cost-production resources with different

  5. Modelling nitrous oxide emissions from organic and conventional cereal-based cropping systems under different management, soil and climate factors

    DEFF Research Database (Denmark)

    Doltra, J; Olesen, Jørgen E; Báez, D;

    2015-01-01

    -based cropping systems. Forage maize was grown in a conventional dairy system at Mabegondo (NW Spain) and wheat and barley in organic and conventional crop rotations at Foulum (NW Denmark). These two European sites represent agricultural areas with high and low to moderate emission levels, respectively. Field...

  6. Effects of Cropping System Change for Paddy Field with Double Harvest Rice on the Crops Growth and Soil Nutrient

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The effects of the cropping system change for paddy field with double harvest rice on crops growth and soil nutrient in red soil were studied. The results indicated that the economic benefit and the ratio of the output to input were all increased in terms of the market price for the crops under various treatments. The greatest economic benefit was obtained in the treatment of paddy-upland rotation, and the corresponding economic benefit was increased by 34.7, 21.4, and 2.2% in comparison with that of control (rice-rice-astragali), pasture, and upland cropping treatments. The economic benefits in pasture and upland cultivation treatments were increased by 11.0 and 31.8%, respectively, when compared with that of the control treatment (CK). The ratio of output to input in pasture, paddy-upland rotation, and upland cropping treatments was enhanced by 0.9, 0.6, and 0.3, respectively, in comparison with that of control. To grow pasture is beneficial for improving soil fertility since the contents of soil organic matter, total nitrogen, total phosphorus, and available phosphorus are all enhanced significantly. However, the concentrations of the soil available nitrogen, the total potassium, the available potassium were somewhat reduced in all the treatments, suggesting that increasing the input of nitrogen,particularly potassium, was necessary under the present fertilization level. Based on the conditions of fertility, climate,cultivation, and management of paddy field with double harvest rice in red soil regions, it is feasible to alter the cultivation system of paddy field with bad irrigation condition. In particular, cultivation systems such as pasture and paddy-upland rotation can be selected to extend because better economic benefit and improvement of soil fertility in the purpose region were obtained.

  7. 新疆连作、轮作棉田可培养的土壤微生物区系及活性分析%Dynamics Analysis of Culturable Soil Microflora and Microbial Activity in Continuous and Rotation Cropping Systems of Xinjiang Cotton

    Institute of Scientific and Technical Information of China (English)

    韩剑; 张静文; 徐文修; 罗明; 吴莉莉

    2011-01-01

    Variation of culturable soil microflora and microbial activity were investigated in continuous and rotation cropping cotton field in Xinjiang.The results showed that culturable microbial population gradually decreased with long-term continuous cropping of cotton.Compared with 5 years continous cropping, the total quantity of soil microbes in 6~8 years, 9~12 years and more than 13 years continuous cropping, decreased by 40.2%, 46.7%, 52.4%,respectively.After more than 5 years continuous cropping, the structure of the soil microbial community transformed from rich nutrition bacteria type to lower nutrition fungi type, the ratio ofbacteria to fungi and actinomycetes to fungi decreased significantly.The amount of nitrogen physiological communities such as ammonifying bacteria, nitrobacteria and aerobic nitrogen-fixing bacteria decreased, while denitrifying bacteria increased.Moreover, continuous cropping resulted in soil respiration intensity and cellulolytic activity reducing.Contrary to continuous cropping, under the cotton/melilotus suavena, tomato, spring wheat or com rotation systems were most beneficial for increasing the total quantity of soil micro-organism, improving the capability of soil microbial activity, adjusting the balance of microbial community.Also there was substantial increasement in the number of azotobacteria.The effects of different rotation modes were different, the benefits of cotton-tomato and cotton-melilotus suavena rotation were more obvious.%研究了新疆连作、轮作棉田土壤可培养微生物区系及活性变化.结果表明,棉花多年连作造成土壤中可培养微生物数量减少,连作6~8年、9~12年、大于13年的棉田与连作小于5年的棉田相比,土壤微生物总量分别下降了40.2%,46.7%,52.4%.连作超过5年后,土壤微生物菌群结构逐渐从高肥的"细菌型"向低肥的"真菌型"转化,细菌/真菌(B/F)和放线菌/真菌(A/F)比值均降低,拮抗菌

  8. Cumulative and residual effects of potato cropping system management strategies on crop and soil health parameters

    Science.gov (United States)

    Soil and crop management practices can greatly affect parameters related to soil health, as well as crop productivity and disease development, and may provide options for more sustainable production. Different 3-yr potato cropping systems focused on specific management goals of soil conservation (SC...

  9. Comparative performance of annual and perennial energy cropping systems under different management regimes

    Energy Technology Data Exchange (ETDEWEB)

    Boehmel, Ute Constanze

    2007-07-18

    The theme of this thesis was chosen against the background of the necessary substitution of fossil fuels and the need to reduce greenhouse gas emissions. One major solution for these topics may be the energy generation from domestically produced biomass. The overall aim of this thesis was the identification of one or more efficient energy cropping systems for Central Europe. The existence of diverse production environments necessitates further diversification and the identification of several energy crops and the development of energy cropping systems suited to those diverse environments. This thesis starts with an introductory essay (chapter 1), which provides the background for renewable energy production, its features, demands and potentials, and the scientific basis of this thesis. Chapters 2 to 6 consist of five manuscripts to be published in reviewed journals (Papers I, II, IV and V) or in a multi-author book (Paper III). Subsequently, the results from all papers are discussed in a general setting (chapter 7), from which a general conclusion is formulated (chapter 8). The basis of the research formed four field experiments, which were conducted at the experimental sites Ihinger Hof, Oberer Lindenhof and Goldener Acker of the University of Hohenheim, in south-western Germany. Paper I addresses the overall objective of this thesis. Selected cropping systems for this experiment were short rotation willow, miscanthus, switchgrass, energy maize and two different crop rotation systems including winter oilseed rape, winter wheat and winter triticale with either conventional tillage or no-till. The systems were cultivated with three different nitrogen fertilizer applications. An energy balance was calculated to evaluate the biomass and energy yields of the different cropping systems. Results indicate that perennial lignocellulosic crops combine high biomass and net energy yields with low input and potential ecological impacts. Switchgrass, which produced low yields

  10. Review of Alternative Management Options of Vegetable Crop Residues to Reduce Nitrate Leaching in Intensive Vegetable Rotations

    Directory of Open Access Journals (Sweden)

    Laura Agneessens

    2014-12-01

    Full Text Available Vegetable crop residues take a particular position relative to arable crops due to often large amounts of biomass with a N content up to 200 kg N ha−1 left behind on the field. An important amount of vegetable crops are harvested during late autumn and despite decreasing soil temperatures during autumn, high rates of N mineralization and nitrification still occur. Vegetable crop residues may lead to considerable N losses through leaching during winter and pose a threat to meeting water quality objectives. However, at the same time vegetable crop residues are a vital link in closing the nutrient and organic matter cycle of soils. Appropriate and sustainable management is needed to harness the full potential of vegetable crop residues. Two fundamentally different crop residue management strategies to reduce N losses during winter in intensive vegetable rotations are reviewed, namely (i on-field management options and modifications to crop rotations and (ii removal of crop residues, followed by a useful and profitable application.

  11. Work and energy in rotating systems

    CERN Document Server

    Manjarres, Diego A; Diaz, Rodolfo A

    2012-01-01

    Literature analyzes the way in which Newton's second law can be used when non-inertial rotating systems are used. However, the treatment of the work and energy theorem in rotating systems is not considered in textbooks. In this paper, we show that the work and energy theorem can still be applied to a closed system of particles in a rotating system, as long as the work of fictitious forces is properly included in the formalism. The coriolis force does not contribute to the work coming from fictitious forces. It worths remarking that real forces that do not do work in an inertial reference frame can do work in the rotating reference frame and viceversa. The combined effects of acceleration of the origin and rotation of the non-inertial system are also studied.

  12. The performance of the EU-Rotate_N model in predicting the growth and nitrogen uptake of rotations of field vegetable crops in a Mediterranean environment

    OpenAIRE

    Nendel, Claas; Venezia, A.; Piro, F.; Ren, T; Lillywhite, Robert; Rahn, C. (Clive)

    2013-01-01

    The EU-Rotate_N model was developed as a tool to estimate the growth and nitrogen (N) uptake of vegetable crop rotations across a wide range of European climatic conditions and to assess the economic and environmental consequences of alternative management strategies. The model has been evaluated under field conditions in Germany and Norway and under greenhouse conditions in China. The present work evaluated the model using Italian data to evaluate its performance in a warm and dry environmen...

  13. Comparative performance of annual and perennial energy cropping systems under different management regimes

    Energy Technology Data Exchange (ETDEWEB)

    Boehmel, Ute Constanze

    2007-07-18

    The theme of this thesis was chosen against the background of the necessary substitution of fossil fuels and the need to reduce greenhouse gas emissions. One major solution for these topics may be the energy generation from domestically produced biomass. The overall aim of this thesis was the identification of one or more efficient energy cropping systems for Central Europe. The existence of diverse production environments necessitates further diversification and the identification of several energy crops and the development of energy cropping systems suited to those diverse environments. This thesis starts with an introductory essay (chapter 1), which provides the background for renewable energy production, its features, demands and potentials, and the scientific basis of this thesis. Chapters 2 to 6 consist of five manuscripts to be published in reviewed journals (Papers I, II, IV and V) or in a multi-author book (Paper III). Subsequently, the results from all papers are discussed in a general setting (chapter 7), from which a general conclusion is formulated (chapter 8). The basis of the research formed four field experiments, which were conducted at the experimental sites Ihinger Hof, Oberer Lindenhof and Goldener Acker of the University of Hohenheim, in south-western Germany. Paper I addresses the overall objective of this thesis. Selected cropping systems for this experiment were short rotation willow, miscanthus, switchgrass, energy maize and two different crop rotation systems including winter oilseed rape, winter wheat and winter triticale with either conventional tillage or no-till. The systems were cultivated with three different nitrogen fertilizer applications. An energy balance was calculated to evaluate the biomass and energy yields of the different cropping systems. Results indicate that perennial lignocellulosic crops combine high biomass and net energy yields with low input and potential ecological impacts. Switchgrass, which produced low yields

  14. Assessing the Influence of Summer Organic Fertilization Combined with Nitrogen Inhibitor on a Short Rotation Woody Crop in Mediterranean Environment

    Directory of Open Access Journals (Sweden)

    Anita Maienza

    2014-01-01

    Full Text Available The European Union Directive 91/676/EEC, known as Nitrates Directive, has dictated basic agronomic principles regarding the use of animal manure source as well as livestock and waste waters from small food companies. The use of nitrification inhibitors together with animal effluents as organic fertilizers could be beneficial for nutrient recycling, plant productivity, and greenhouse gas emission and could offer economic advantages as alternative to conventional fertilizers especially in the Mediterranean region. The aim of the present study was to investigate differences in plant productivity between bovine effluent treatments with (or without addition of a nitrification inhibitor (3,4 DMPP in a short rotation woody crop system. Results of the field experiment carried out in a Mediterranean dry environment indicated that the proposed strategy could improve tree growth with indirect, beneficial effects for agroforestry systems.

  15. Boundary layer control of rotating convection systems.

    Science.gov (United States)

    King, Eric M; Stellmach, Stephan; Noir, Jerome; Hansen, Ulrich; Aurnou, Jonathan M

    2009-01-15

    Turbulent rotating convection controls many observed features of stars and planets, such as magnetic fields, atmospheric jets and emitted heat flux patterns. It has long been argued that the influence of rotation on turbulent convection dynamics is governed by the ratio of the relevant global-scale forces: the Coriolis force and the buoyancy force. Here, however, we present results from laboratory and numerical experiments which exhibit transitions between rotationally dominated and non-rotating behaviour that are not determined by this global force balance. Instead, the transition is controlled by the relative thicknesses of the thermal (non-rotating) and Ekman (rotating) boundary layers. We formulate a predictive description of the transition between the two regimes on the basis of the competition between these two boundary layers. This transition scaling theory unifies the disparate results of an extensive array of previous experiments, and is broadly applicable to natural convection systems.

  16. Diazotroph community structure and abundance in wheat-fallow and wheat-pea crop rotations

    Science.gov (United States)

    Biological input of nitrogen (N) from the atmosphere either through free-living diazotrophs or legume-associated rhizobia can help alleviate fertilizer use in agricultural systems. In this study, we investigated the effect of N fertilizer and winter pea (Pisum sativum L.) crop on the diversity and a...

  17. Changes in soil C-isotopic composition in an agroecosystem under Free Air Carbon dioxide Enrichment (FACE) treatment during a crop rotation period.

    Science.gov (United States)

    Giesemann, Anette

    2005-01-01

    FACE (Free Air Carbon dioxide Enrichment) has been used since 1999 to evaluate the effects of future atmospheric CO(2) concentrations on an arable crop agroecosystem. The experiment conducted at the Institute of Agroecology at the Federal Research Centre in Braunschweig consists of a typical local crop rotation of winter barley, a cover crop, sugar beet and winter wheat. The atmospheric CO2 concentration of ambient air is about 375 ppm with a delta13C value of -7 to -9 per thousand, and 550 ppm (delta13C value = -20.2 per thousand) during daylight hours in the rings fumigated with additional CO2. Thus, the surplus C can be traced in the agricultural system. Over the course of the first experimental period (3-year crop rotation period), the C-isotopic composition and the C concentration in soil were monitored monthly. Plant samples were analysed according to the relevant developmental stages of the crop under cultivation. A 13C depletion was observed in plant parts, as well as in soil samples from the FACE rings under CO2 enrichment, indicating that labelled C has reached both respective ecosystem compartments. Albeit farming management practice (especially ploughing) leads to a mixing of 'old' and 'new' C compounds throughout all soil horizons down to the end of the ploughing layer and resulted in a heterogeneous distribution of newly formed C compounds in the soil, isotope analysis of soil C reflected where the surplus C went.

  18. Effects of crop rotation and nonfumigant nematicides on peanut and corn yields in fields infested with criconemella species.

    Science.gov (United States)

    Ayers, A R; Duncan, H E; Barker, K R; Beute, M K

    1989-04-01

    The effects of nematicide treatments and corn-peanut cropping sequences on the population development of Criconemella ornata, and C. sphaerocephala and the related impact on crop yields were investigated at two North Carolina locations. Criconemella ornata and C. sphaerocephala were present at the Norman Perry farm, Bertie County (BERTIE); however, only C. ornata was found at the Central Crops Research Station, Johnston County (CCRS). An untreated control was compared to aldicarb 15G, carbofuran 15G, ethoprop 10G, and terbufos 15G granular formulations applied at a rate of 2.2 kg a.i./ha. The cropping sequences were monocuhured corn (C-C-C); monocultured peanut (P-P-P); and two corn-peanut (C-P-C; P-C-P) rotations. Nematicides were inconsistent in controlling C. sphaerocephala and C. ornata. Nematicide treatments enhanced corn yields in the monoculture-cropping cycle in the final year of the experiment at CCRS. Peanut yields were greater in the rotated cropping sequence than under monoculture at BERTIE, but rotation had less effect on peanut yields at CCRS. Declining yields were correlated with an increase in numbers of nematodes. Corn was an intermediate host for C. sphaerocephala and a moderate to poor host for C. ornata. Peanut was an excellent host for C. ornata and a poor host for C. sphaerocephala.

  19. Distribution characteristics of soil profile nitrous oxide concentration in paddy fields with different rice-upland crop rotation systems%不同水旱轮作体系稻田土壤剖面N2O的分布特征

    Institute of Scientific and Technical Information of China (English)

    刘平丽; 张啸林; 熊正琴; 黄太庆; 丁敏; 王金阳

    2011-01-01

    To investigate the dynamic distribution patterns of nitrous oxide (N2O) in the soil pro-files in paddy fields with different rice-upland crop rotation systems, a special soil gas collection de-vice was adopted to monitor the dynamics of N2O at the soil depths 7, 15, 30, and 50 cm in the paddy fields under both flooding and drainage conditions. Two rotation systems were installed, i. e. , wheat-single rice and oilseed rape-double rice, each with or without nitrogen (N) applica-tion. Comparing with the control, N application promoted the N2O production in the soil profiles significantly (P<0.01) , and there existed significant correlations in the N2O concentration among the four soil depths during the whole observation period (P<0.01). In the growth seasons of winter wheat and oilseed rape under drainage condition and with or without N application, the N2O con-centrations at the soil depths 30 cm and 50 cm were significantly higher than those at the soil depths 7 cm and 15 cm; whereas in the early rice growth season under flooding condition and without N ap-plication, the N2O concentrations at the soil depth 7 cm and 15 cm were significantly higher than those at the soil depths 30 cm and 50 cm (P<0.05). No significant differences were observed in the N2O concentrations at the test soil depths among the other rice cropping treatments. The soil N2 0 concentrations in the treatments without N application peaked in the transitional period from the upland crops cropping to rice planting, while those in the treatments with N application peaked right after the second topdressing N of upland crops. Relatively high soil N2O concentrations were ob-served at the transitional period from the upland crops cropping to rice planting.%通过原位采集淹水和排水状态下土壤剖面4个层次的气体,研究氧化亚氮(N2O)在水旱轮作体系稻田土壤剖面中的动态分布特征.试验设置小麦-单季稻和油菜-双季稻两种轮作体系,包括施N和不施N两

  20. Soil N mineralization in a dairy production system with grass and forage crops

    NARCIS (Netherlands)

    Verloop, J.; Hilhorst, G.J.; Oenema, J.; Keulen, van H.; Sebek, L.B.J.; Ittersum, van M.K.

    2014-01-01

    This paper describes the dynamics of soil N mineralization in the experimental intensive dairy farming system ‘De Marke’ on a dry sandy soil in the Netherlands. We hypothesized that knowledge of the effects of crop rotation on soil N mineralization and of the spatial and temporal variability of soil

  1. Chromolaena odorata fallow in food cropping systems. An agronomic assessment in South-West Ivory Coast.

    NARCIS (Netherlands)

    Slaats, J.J.P.

    1995-01-01

    In tropical Africa, traditional shifting cultivation can no longer provide sufficient food for the rapidly increasing population, whereas it threatens the remaining forests. An alternative is a fallow system based on the shrub Chromolaena odorata. Food crop cultivation in rotation with this fallow t

  2. Net carbon balance of three full crop rotations at an agricultural site near Gebesee, Germany

    Science.gov (United States)

    Hurkuck, M.; Brümmer, C.; Kolle, O.; Kutsch, W. L.; Moffat, A. M.; Mukwashi, K.; Truckenbrodt, S. C.; Herbst, M.

    2015-12-01

    Continuous eddy-covariance (EC) measurements of biosphere-atmosphere CO2 and H2O exchange have been conducted since 2001 at an agricultural site near Gebesee, Germany, thus providing one of the longest EC time series of European croplands. During the experimental period, winter wheat and winter barley were alternately planted with potatoes, sugar beet, rape, and peppermint covering three full crop rotations (2001-2004, 2005-2009, and 2010-2014). In this study, data of 14 years of net ecosystem CO2 exchange (NEE) and evapotranspiration (E) were re-calculated. Based on these data, we present the net carbon (C) balance (net biome production, NBP) accounting for any additional C input by fertilization and C output by harvest. Further emphasis was placed on the sensitivity of water use efficiency (WUE) and E to climate and crop type. The main aim was to investigate the interannual variability in both NBP and WUE, thus disentangling the impacts of climatic conditions and land management on the net C balance as well as on WUE and E.

  3. Plants for space plantations. [crops for closed life support systems

    Science.gov (United States)

    Nikishanova, T. I.

    1978-01-01

    Criteria for selection of candidate crops for closed life support systems are presented and discussed, and desired characteristics of candidate higher plant crops are given. Carbohydrate crops, which are most suitable, grown worldwide are listed and discussed. The sweet potato, ipomoea batatas Poir., is shown to meet the criteria to the greatest degree, and the criteria are recommended as suitable for initial evaluation of candidate higher plant crops for such systems.

  4. The impact of new energy crops on weed flora diversification in energy cropping systems

    Directory of Open Access Journals (Sweden)

    Glemnitz, Michael

    2016-02-01

    Full Text Available Despite various options in energy cropping for the diversification of agricultural land use, such as the introduction of new crops, in practice, there is a one-sided orientation toward the use of maize as biogas feedstock in Germany. One reason, why they are not yet introduced in practice, is that for most of them neither the agricultural feasibility nor their ecological and economic benefit could be clearly shown to the farmers up to now. As part of the research projects “Site-adapted Cropping Systems for Energy Crops” (EVA, and “Optimized energy cropping systems for the sustainable biogas production (Upscaling” the effects of three new energy crops have been tested under real farm conditions in two different regions in the northern part of Germany. The large scale field trial consisted of the comparison of the following energy crops: 0- maize as reference crop, 1- perennial Silphie (Silphium perfoliatum, 2- Szarvasi grass (Agropyron elongatum, and 3-perennial wild flower mixture. The trail has been investigated regarding the following effects: α-diversity at the plot scale, contribution to the β-diversity among the crops and species composition. The results suggest that the integration of the new perennial energy crop might contribute to an essential weed diversity enhancement. Weed flora diversity was between 2-4 times higher in most of the cases in the new energy crops compared to maize.

  5. The Use of Cover Crops as Climate-Smart Management in Midwest Cropping Systems

    Science.gov (United States)

    Basche, A.; Miguez, F.; Archontoulis, S.; Kaspar, T.

    2014-12-01

    The observed trends in the Midwestern United States of increasing rainfall variability will likely continue into the future. Events such as individual days of heavy rain as well as seasons of floods and droughts have large impacts on agricultural productivity and the natural resource base that underpins it. Such events lead to increased soil erosion, decreased water quality and reduced corn and soybean yields. Winter cover crops offer the potential to buffer many of these impacts because they essentially double the time for a living plant to protect and improve the soil. However, at present, cover crops are infrequently utilized in the Midwest (representing 1-2% of row cropped land cover) in particular due to producer concerns over higher costs and management, limited time and winter growing conditions as well as the potential harm to corn yields. In order to expand their use, there is a need to quantify how cover crops impact Midwest cropping systems in the long term and namely to understand how to optimize the benefits of cover crops while minimizing their impacts on cash crops. We are working with APSIM, a cropping systems platform, to specifically quantify the long term future impacts of cover crop incorporation in corn-based cropping systems. In general, our regional analysis showed only minor changes to corn and soybean yields (cover crop was or was not included in the simulation. Further, a "bad spring" scenario (where every third year had an abnormally wet/cold spring and cover crop termination and planting cash crop were within one day) did not result in any major changes to cash crop yields. Through simulations we estimate an average increase of 4-9% organic matter improvement in the topsoil and an average decrease in soil erosion of 14-32% depending on cover crop planting date and growth. Our work is part of the Climate and Corn-based Cropping Systems Coordinated Agriculture Project (CSCAP), a collaboration of eleven Midwestern institutions established

  6. Improving Resilience of Northern Field Crop Systems Using Inter-Seeded Red Clover: A Review

    Directory of Open Access Journals (Sweden)

    William Deen

    2013-02-01

    Full Text Available In light of the environmental challenges ahead, resilience of the most abundant field crop production systems must be improved to guarantee yield stability with more efficient use of nitrogen inputs, soil and water resources. Along with genetic and agronomic innovations, diversification of northern agro-ecosystems using inter-seeded legumes provides further opportunities to improve land management practices that sustain crop yields and their resilience to biotic and abiotic stresses. Benefits of legume cover crops have been known for decades and red clover (Trifolium pratense is one of the most common and beneficial when frost-seeded under winter wheat in advance of maize in a rotation. However, its use has been declining mostly due to the use of synthetic fertilizers and herbicides, concerns over competition with the main crop and the inability to fully capture red clover benefits due to difficulties in the persistence of uniform stands. In this manuscript, we first review the environmental, agronomic, rotational and economical benefits associated with inter-seeded red clover. Red clover adaptation to a wide array of common wheat-based rotations, its potential to mitigate the effects of land degradation in a changing climate and its integration into sustainable food production systems are discussed. We then identify areas of research with significant potential to impact cropping system profitability and sustainability.

  7. A Rotation Scaling and Cropping Inavariant Second Generation Watermarking Scheme Based on Hough Transform

    Institute of Scientific and Technical Information of China (English)

    JIZhen; ZHANGJihong; XIAOWeiwei

    2003-01-01

    In this paper,a scheme which follows the seconde generation watermarking(2GW)paradigm is proposed.The goal of this proposed scheme is basically to increase the robustness against geometric attacks.The host image is decomposed with the wavelet packet.The bit stream of binary watermark is coded into several patterns with salient feature.The circular feature is used in this paper,because:(a)the computational complexity of the method grows rapidly with more complex shapes.(b) the circle is rotation -invariant and partially scale-invariant.(c)the circular feature can be detected by Hough transform effectively.These patterns are embedded into wavelet packet coefficients according to human perceptual charac teristics.A new HVS mask based on wavelet transform is proposed with consideration of local texture characteristics.The introduction of HVS caharacteristics boosts the performance of the whole scheme.Then,the watermarked image is generated by WP reconstruction.For the detection of watermark,the geometric distortion is calibrated for the contaminated watermarked image, then it is decomposed with the same WP used in embedding procedure.Hough transform is used to detect the circular features in the WP Coefficients.This scheme has the following characteristis:(a)robustness against the common geometric attacks(rotation,scaling,cropping,and etc)is improved significantly.(b)human perceptual characteristics is taken into consideration,so the tradeoff between invisibility and robustness is improved.Results of extensive experiments indicate that this proposed scheme is significantly effective in resisting various attacks such as rotation,scaling,JPEG compressing,adding noise,etc.

  8. Controle de plantas daninhas em feijão num sistema de rotação culturas em plantio direto Weed control in beans in a no-tillage crop rotation system

    Directory of Open Access Journals (Sweden)

    Benedito N. Rodrigues

    1995-01-01

    Full Text Available O objetivo deste trabalho foi selecionar culturas de inverno para formação de cobertura morta que reduza a população de plantas daninhas na cultura do feijão (Phaseolus vulgaris. Ocupou-se o terreno durante o ano todo, com a sucessão, em plantio direto, de pousio ou cultura de inverno/feijão/cultura para silagem, estudando-se três modalidades de controle de plantas daninhas na cultura do feijão. A maior renda líquida acumulada após duas safras foi obtida com feijão semeado sobre palha de aveia-preta e controle de plantas daninhas com um gramicida pré-emergente, completando-se com capinas, quando necessário.This study was undertaken to select winter crops for mulching to reduce the weed infestation and to lower weed control costs in bean (Phaseolus vulgaris production. The soil was kept convered all the year under no-tillage with a sequence of a winter crop or fallow/beans/silage crop. Three weed control methods for beans were studied. After two complete crop sequences, the highest total net income was obtained with the beans directly drilled on the black oats (Avena strigosa mulching, spraying a pre-emergence grasskiller plus hoeing when needed.

  9. Integration of crop rotation and arbuscular mycorrhiza (AM) inoculum application for enhancing AM activity to improve phosphorus nutrition and yield of upland rice (Oryza sativa L.).

    Science.gov (United States)

    Maiti, Dipankar; Toppo, Neha Nancy; Variar, Mukund

    2011-11-01

    Upland rice (Oryza sativa L.) is a major crop of Eastern India grown during the wet season (June/July to September/October). Aerobic soils of the upland rice system, which are acidic and inherently phosphorus (P) limiting, support native arbuscular mycorrhizal (AM) activity. Attempts were made to improve P nutrition of upland rice by exploiting this natural situation through different crop rotations and application of AM fungal (AMF) inoculum. The effect of a 2-year crop rotation of maize (Zea mays L.) followed by horse gram (Dolichos biflorus L.) in the first year and upland rice in the second year on native AM activity was compared to three existing systems, with and without application of a soil-root-based inoculum. Integration of AM fungal inoculation with the maize-horse gram rotation had synergistic/additive effects in terms of AMF colonization (+22.7 to +42.7%), plant P acquisition (+11.2 to +23.7%), and grain yield of rice variety Vandana (+25.7 to +34.3%).

  10. Net global warming potential and greenhouse gas intensity influenced by irrigation, tillage, crop rotation, and nitrogen fertilization

    Science.gov (United States)

    Little information exists about sources and sinks of greenhouse gases (GHGs) affected by management practices to account for net emissions from agroecosystems. We evaluated the effects of irrigation, tillage, crop rotation, and N fertilization on net global warming potential (GWP) and greenhouse gas...

  11. Crop yield, root growth, and nutrient dynamics in a conventional and three organic cropping systems with different levels of external inputs and N re-cycling through fertility building crops

    DEFF Research Database (Denmark)

    Thorup-Kristensen, Kristian; Dresbøll, Dorte Bodin; Kristensen, Hanne Lakkenborg

    2012-01-01

    calculated based on total land area was only 63% of conventional yields. Differences in quality parameters of the harvested crops, i.e. nutrient content, dry matter content or damages by pests or diseases were few and not systematic, whereas clear effects on nutrient balances and nitrogen leaching indicators...... of the organic rotation, both relying on green manures and catch crops grown during the autumn after the main crop as their main source of soil fertility, and the O3 system further leaving rows of the green manures to grow as intercrops between vegetable rows to improve the conditions for biodiversity...

  12. Biomass productivity and radiation utilisation of innovative cropping systems for biorefinery

    DEFF Research Database (Denmark)

    Manevski, Kiril; Lærke, Poul Erik; Jiao, Xiurong

    2017-01-01

    for biomass production, and compare their performance with traditional cropping systems commonly used in northern European agriculture. Measurements of biomass yield from 2012 to 2015 at two Danish sites differing in soil type and climatic conditions were conducted in three main cropping systems: i) optimised...... rotation of annual crops (maize, beet, hemp/oat, triticale, winter rye and winter rapeseed), ii) perennial crops intensively fertilised (festulolium, reed canary, cocksfoot and tall fescue), low-fertilised (miscanthus) or unfertilised (grass-legume mixtures) and iii) traditional systems (continuous...... on biodiversity. The fraction of intercepted photosynthetically active radiation (fIpar), the accumulated intercepted photosynthetically active radiation (Ipar) and the radiation use efficiency (RUE) were determined from canopy radiations measured biweekly for three years. These results showed a higher annual...

  13. Biomassa, atividade microbiana e FMA em rotação cultural milho/feijão-de-corda utilizando-se águas salinas Biomass, microbial activity and AMF in crop rotation system of maize/cowpea using saline water

    Directory of Open Access Journals (Sweden)

    Maria Eloneide de Jesus Bezerra

    2010-12-01

    Full Text Available O objetivo deste trabalho foi avaliar a influência da irrigação com água de alta e baixa salinidade sobre variáveis microbiológicas do solo em área submetida à rotação de cultura entre milho (Zea Mays L. e feijão-de-corda (Vigna unguiculata L.. A área destinada ao experimento foi dividida em duas subáreas, sendo realizados quatro cultivos: dois cultivos irrigados na estação seca e dois de sequeiro na estação chuvosa. O estudo foi conduzido em campo, utilizando-se o delineamento em blocos ao acaso, com cinco repetições. Nos cultivos irrigados foram usadas água com as seguintes condutividades elétricas (CEa: 0,8; 2,2; 3,6 e 5,0 dS m-1. Os cultivos de sequeiro foram realizados nas mesmas parcelas que foram cultivadas na estação seca, as quais permaneceram demarcadas e identificadas. No início e ao final de cada cultivo, foram coletadas amostras em duas subáreas na região radicular das plantas, no terço médio da fileira central de cada parcela. O aumento da salinidade da água de irrigação promoveu aumento do número total de esporos de fungos micorrízicos arbusculares FMA e reduziu a respiração basal do solo, o carbono da biomassa e o coeficiente metabólico microbiano (qCO2, principalmente na área cultivada com feijão-de-corda. O gênero Glomus respondeu por mais de 70% dos esporos totais encontrados, sendo que essa percentagem aumentou nos tratamentos com maior salinidade nos cultivos da estação seca. Os dados não evidenciaram qualquer efeito negativo da salinidade residual sobre as variáveis microbiológicas avaliadas, em função da irrigação com água salina durante os cultivos da estação seca.This work carred out the influence of irrigation with water of high and low salinity on soil microbial variables in area under the crop rotation between maize (Zea Mays L. and cowpea (Vigna unguiculata L.. The area for the experiment was divided into two sub areas being made four crops, two crops irrigated in

  14. A Rotative Electrical Impedance Tomography Reconstruction System

    Energy Technology Data Exchange (ETDEWEB)

    Yu, F-M [St. John' s and St. Mary' s Institute of Technology, Department of computer science and information Engineering, 499, Sec. 4, Tam King Road Tamsui, Taipei, Taiwan (China); Huang, C-N [National Central University, Department of Electrical Engineering, No.300, Jungda Rd, Jhongli City, 320 Taoyuan, Taiwan (China); Chang, F-W [National Central University, Department of Electrical Engineering, No.300, Jungda Rd, Jhongli City, 320 Taoyuan, Taiwan (China); Chung, H-Y [National Central University, Department of Electrical Engineering, No.300, Jungda Rd, Jhongli City, 320 Taoyuan, Taiwan (China)

    2006-10-15

    Electrical impedance tomography (EIT) is a powerful tool for mapping the conductivity distribution of estimated objects. The EIT system is entirely implemented by electrical technique, so it is a relatively cheap system and data can be collected very rapidly. But it has few commercially medical EIT systems available. This is because impedance image unable to achieve the essential spatial resolution and this technique has an intrinsically poor signal to noise ratio. In this paper, we have developed a high performance rotative EIT system (REIT) for expanding the independent measurements. By rotate the electrodes successive, REIT could change the position of electrodes and acquire more measurement data. This rotative measurement method not only can increase the resolution of impedance images, but also reduce the complexity of measurement system. We hope the improvement of REIT will bring some help in electrical impedance tomography.

  15. [Influence of paddy rice-upland crop rotation of cold-waterlogged paddy field on crops produc- tion and soil characteristics].

    Science.gov (United States)

    Wang, Fei; Li, Qing-hua; Lin, Cheng; He, Chun-mei; Zhong, Shao-jie; Li, Yu; Lin, Xin-jian; Huang, Jian-cheng

    2015-05-01

    Two consecutive years (4-crop) experiments were conducted to study the influence of different paddy rice-upland crop rotation in cold-waterlogged paddy field on the growth of crops and soil characteristics. The result showed that compared with the rice-winter fallow (CK) pattern, the two-year average yield of paddy rice under four rotation modes, including rape-rice (R-R), spring corn-rice (C-R), Chinese milk vetch-rice (M-R) and bean-rice (B-R), were increased by 5.3%-26.7%, with significant difference observed in C-R and R-R patterns. Except for M-R pattern, the annual average total economic benefits were improved by 79.0%-392.4% in all rotation pattern compared with the CK, and the ration of output/input was enhanced by 0.06-0.72 unit, with the most significant effect found in the C-R pattern. Likewise, compared with the CK, the contents of chlorophyll and carotenoid, and net photosynthetic rate (Pn) of rice plant were all increased during the full-tillering stage of rice in all rotation patterns. The rusty lines and rusty spots of soils were more obvious compared with the CK during the rice harvest, particularly in R-R, C-R and B-R patterns. The ratio of water-stable soil macro aggregates of plough layer of soil (> 2 mm) decreased at different levels in all rotation patterns while the ratios of middle aggregate (0.25-2 mm, expect for M-R) and micro aggregate of soil (benefits, and soil physical and chemical properties were improved.

  16. Much Improved Irrigation Use Efficiency in an Intensive Wheat-Maize Double Cropping System in the North China Plain

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Crop yield and water use efficiency (WUE) in a wheat-maize double cropping system are influenced by short and uneven rainfalls in the North China Plain (NCP). A 2-year experiment was conducted to investigate the effects of irrigation on soil water balance, crop yield and WUE to improve irrigation use efficiency in the cropping system. Soil water depletion (△SWS)by crop generally decreased with the increase of irrigation and rainfall, while △SWS for the whole rotation was relatively stable among these irrigation treatments. High irrigations in wheat season increased initial soil moisture and △SWS for subsequent maize especially in the drought season. Initial soil water influenced mainly by the irrigation and rainfall in the previous crop season, is essential to high yield in such cropping systems. Grain yield decreased prior to evapotranspiration(ET) when ET reached about 300 mm for wheat, while maize showed various WUEs with similar seasonal ET. For whole rotation, WUE declined when ET exceeded about 650 mm. These results indicate great potential for improving irrigation use efficiency in such wheat-maize cropping system in the NCP. Based on the present results, reasonable irrigation schedules according to different annual rainfall conditions are presented for such a cropping system.

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

    Science.gov (United States)

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

    2015-04-01

    Protecting natural resources while maintaining or maximizing crop yield potential is of utmost importance for sustainable crop and livestock production systems. Since soil organic matter and its decomposition by soil organisms is at the very foundation of healthy productive soils, systems research at the North Dakota State University Dickinson Research Extension Center is evaluating seasonal soil nitrogen fertility within an integrated crop and livestock production system. The 5-year diverse crop rotation is: sunflower (SF) - hard red spring wheat (HRSW) - fall seeded winter triticale-hairy vetch (THV; spring harvested for hay)/spring seeded 7-species cover crop (CC) - Corn (C) (85-90 day var.) - field pea-barley intercrop (PBY). The HRSW and SF are harvested as cash crops and the PBY, C, and CC are harvested by grazing cattle. In the system, yearling beef steers graze the PBY and C before feedlot entry and after weaning, gestating beef cows graze the CC. Since rotation establishment, four crop years have been harvested from the crop rotation. All crops have been seeded using a JD 1590 no-till drill except C and SF. Corn and SF were planted using a JD 7000 no-till planter. The HRSW, PBY, and CC were seeded at a soil depth of 3.8 cm and a row width of 19.1 cm. Seed placement for the C and SF crops was at a soil depth of 5.1 cm and the row spacing was 0.762 m. The plant population goal/ha for C, SF, and wheat was 7,689, 50,587, and 7,244 p/ha, respectively. During the 3rd cropping year, soil bulk density was measured and during the 4th cropping year, seasonal nitrogen fertility was monitored throughout the growing season from June to October. Seasonal nitrate nitrogen (NO3-N), ammonium nitrogen (NH4-N), total season mineral nitrogen (NO3-N + NH4-N), cropping system NO3-N, and bulk density were measured in 3 replicated non-fertilized field plot areas within each 10.6 ha triple replicated crop fields. Within each plot area, 6 - 20.3 cm x 0.61 m aluminum irrigation

  18. Cultivar specific plant-soil feedback overrules soil legacy effects of elevated ozone in a rice-wheat rotation system

    NARCIS (Netherlands)

    Li, Qi; Yang, Yue; Bao, Xuelian; Zhu, Jianguo; Liang, Wenju; Bezemer, T. Martijn

    2016-01-01

    Abstract Tropospheric ozone has been recognized as one of the most important air pollutants. Many studies have shown that elevated ozone negatively impacts yields of important crops such as wheat or rice, but how ozone influences soil ecosystems of these crops and plant growth in rotation systems is

  19. Promoting Cassava as an Industrial Crop in Ghana: Effects on Soil Fertility and Farming System Sustainability

    Directory of Open Access Journals (Sweden)

    S. Adjei-Nsiah

    2012-01-01

    Full Text Available Cassava is an important starchy staple crop in Ghana with per capita consumption of 152.9 kg/year. Besides being a staple food crop, cassava can be used as raw material for the production of industrial starch and ethanol. The potential of cassava as an industrial commercial crop has not been exploited to a large extent because of perceptions that cassava depletes soils. Recent finding from field studies in the forest/savannah transitional agroecological zone of Ghana indicates that when integrated in the cropping system as a form of rotation, cassava contributes significantly to maintenance of soil fertility, and thus large scale production of cassava for industrial use can contribute to poverty reduction in an environmentally responsive way. This paper discusses the role of cassava cultivation in soil fertility management and its implication for farming system sustainability and industrialization.

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

    Science.gov (United States)

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

    2016-04-01

    Soil quality of shallow paddy soils may be improved by introducing upland crops and thus a more diverse crop cultivation pattern. Yet, the causal relationship between crop performance and enhanced soil traits in rice-upland crop rotations remains elusive. The objectives of this study were to (i) find correlations among soil properties under different rice-upland crop systems and link selected soil properties to rice growth and yield, (ii) present appropriate values of soil parameters for sustainable rice productivity in heavy clay soil, (iii) evaluate the effect of rotating rice with upland crops on rice yield and economic benefit in a long-term experiment. A rice-upland crop rotational field experiment in the Vietnamese Mekong delta was conducted for 10 years using a randomized complete block design with four treatments and four replications. Treatments were: (i) rice-rice-rice (control - conventional system as farmers' practice), (ii) rice-maize-rice, (iii) rice-mung bean-rice, and (iv) rice-mung bean-maize. Soil and plant sampling were performed after harvest of the rice crop at the end of the final winter-spring cropping season (i.e. year 10). Results show differences in rice growth and yield, and economic benefit as an effect of the crop rotation system. These differences were linked with changes in bulk density, soil porosity, soil aggregate stability index, soil penetration resistance, soil macro-porosity, soil organic carbon, acid hydrolysable soil C and soil nutrient elements, especially at soil depth of 20-30 cm. This is evidenced by the strong correlation (P soil properties such as bulk density, porosity, penetration resistance, soil organic carbon and Chydrolysable. It turned out that good rice root growth and rice yield corresponded to bulk density values lower than 1.3 Mg m-3, soil porosity higher than 50%, penetration resistance below 1.0 MPa, and soil organic carbon above 25 g kg-1. The optimal soil depth without restriction for rice root elongation

  1. Divesting in crop diversity: trade-offs of modern cropping systems

    Science.gov (United States)

    Engstrom, P.

    2013-12-01

    Since the advent of the Green Revolution in the 1960's, agriculture has experienced great advances in yield, seed genetics and management. This focus on increased yields and production came at the cost of many marginal, traditional crops because they could no longer compete with the bountiful harvests of massive mono-culture food systems. In the modern agricultural world, three staple crops are responsible for 46% of global agricultural production on 33% of global harvested area. Further, seventeen crops account for 73% of global crop production and use 58% of global harvested area. How has the distribution of individual crops today changed from before the Green Revolution began, and what are the broader implications of these changes for our food systems?

  2. Rendimento de soja em sistema de integração lavoura-pecuária: efeito de métodos e intensidades de pastejo Soybean yield in an animal-crop rotation system: effects of grazing methods and intensities

    Directory of Open Access Journals (Sweden)

    Robson Lunardi

    2008-06-01

    Full Text Available Sistemas de integração lavoura-pecuária têm despertado o interesse de produtores que buscam a diversificação das atividades e o aumento da rentabilidade. O objetivo deste trabalho foi avaliar a influência de métodos e intensidades de pastejo de ovinos no rendimento da soja cultivada em dois espaçamentos entre linhas, em um sistema de integração lavoura-pecuária. O experimento foi conduzido no município de Eldorado do Sul - RS, na Estação Experimental Agronômica - UFRGS na safra 2003/2004, cujas coordenadas geográficas são 30005'22" S de latitude e 51039'08" W de longitude. O delineamento experimental foi em blocos casualizados num fatorial com duas intensidades de pastejo, baixa e moderada, dois métodos de pastejo, contínuo e rotacionado, e dois espaçamentos entre fileiras de soja, 0,2 e 0,4m, com quatro repetições. Uma área foi adicionada como testemunha sem pastejo. Avaliaram-se o rendimento e os componentes do rendimento da soja. A produção de soja foi superior nos tratamentos submetidos a pastejo em comparação aos não-pastejados. Dentre os pastejados, o rendimento de soja foi superior na intensidade de pastejo baixa em comparação com a intensidade moderada. A intensidade de pastejo utilizada no inverno é o principal determinante do sucesso desse sistema de integração lavoura-pecuária.Animal-crop rotation systems are fostering the interest of farmers searching for diversification and the increase of profitability. The experiment aimed to evaluate the influence of grazing methods and intensities applied on winter pastures grazed by lambs and its consequence for soybean yield cultivated in succession. This crop-animal rotation trial was conducted in 2003/2004 at UFRGS Agricultural Research Station (Universidade Federal do Rio Grande do Sul in Eldorado do Sul, Rio Grande do Sul state, Brazil, whose geographical coordinates are 30005'22" S latitude and 51039'08" W longitude. The experimental design was a

  3. Conservation agriculture increases soil organic carbon and residual water content in upland crop production systems

    Directory of Open Access Journals (Sweden)

    Victor B. Ella

    2016-01-01

    Full Text Available Conservation agriculture involves minimum soil disturbance, continuous ground cover, and diversified crop rotations or mixtures. Conservation agriculture production systems (CAPS have the potential to improve soil quality if appropriate cropping systems are developed. In this study, five CAPS including different cropping patterns and cover crops under two fertility levels, and a plow-based system as control, were studied in a typical upland agricultural area in northern Mindanao in the Philippines. Results showed that soil organic carbon (SOC at 0- 5-cm depth for all CAPS treatments generally increased with time while SOC under the plow-based system tended to decline over time for both the high (120, 60 and 60 kg N P K ha-1 and moderate (60-30-30 kg N P K ha-1 fertility levels. The cropping system with maize + Stylosanthes guianensis in the first year followed by Stylosanthes guianensis and fallow in the second year, and the cassava + Stylosanthes guianensis exhibited the highest rate of SOC increase for high and moderate fertility levels, respectively. After one, two, and three cropping seasons, plots under CAPS had significantly higher soil residual water content (RWC than under plow-based systems. Results of this study suggest that conservation agriculture has a positive impact on soil quality, while till systems negatively impact soil characteristics.

  4. Farm-scale costs and returns for second generation bioenergy cropping systems in the US Corn Belt

    Science.gov (United States)

    Manatt, Robert K.; Hallam, Arne; Schulte, Lisa A.; Heaton, Emily A.; Gunther, Theo; Hall, Richard B.; Moore, Ken J.

    2013-09-01

    While grain crops are meeting much of the initial need for biofuels in the US, cellulosic or second generation (2G) materials are mandated to provide a growing portion of biofuel feedstocks. We sought to inform development of a 2G crop portfolio by assessing the profitability of novel cropping systems that potentially mitigate the negative effects of grain-based biofuel crops on food supply and environmental quality. We analyzed farm-gate costs and returns of five systems from an ongoing experiment in central Iowa, USA. The continuous corn cropping system was most profitable under current market conditions, followed by a corn-soybean rotation that incorporated triticale as a 2G cover crop every third year, and a corn-switchgrass system. A novel triticale-hybrid aspen intercropping system had the highest yields over the long term, but could only surpass the profitability of the continuous corn system when biomass prices exceeded foreseeable market values. A triticale/sorghum double cropping system was deemed unviable. We perceive three ways 2G crops could become more cost competitive with grain crops: by (1) boosting yields through substantially greater investment in research and development, (2) increasing demand through substantially greater and sustained investment in new markets, and (3) developing new schemes to compensate farmers for environmental benefits associated with 2G crops.

  5. An original experiment to determine impact of catch crop introduction in a crop rotation on N2O production fate

    Science.gov (United States)

    Tallec, Tiphaine; Le Dantec, Valérie; Zawilski, Bartosz; Brut, Aurore; Boussac, Marion; Ferlicoq, Morgan; Ceschia, Eric

    2015-04-01

    The raise in N2O concentration from the preindustrial era (280 ppb) to nowadays (324 ppb) is estimated to account for approximately 6% of the predicted global warming (IPCC 2014). Worldwide, soils are considered to be the dominant source of N2O, releasing an estimated 9.5 Tg N2O-N y-1 (65% of global N2O emissions), of which 36.8% are estimated to originate from agricultural soils (IPCC 2001). Most N2O originating from agricultural soils is a by- or end-product of nitrification or denitrification. The fate of N2O produced by microbiological processes in the subsoil is controlled by biotic (crop species, occurring soil organic matter, human pressure via mineral and organic nitrogen fertilisation) and abiotic (environmental conditions such as temperature, soil moisture, pH, etc.) factors. In cropland, contrary to forest and grassland, long bare soil periods can occurred between winter and summer crops with a high level of mineral (fertilizer) and organic (residues) nitrogen remaining in the soil, causing important emissions of carbon and nitrogen induced by microbial activities. Introduction of catch crop has been identified as an important mitigation option to reduce environmental impact of crops mainly thanks to their ability to increase CO2 fixation, to decrease mineral nitrogen lixiviation and also reduce the potential fate of N2O production. Uncertainty also remains about the impact of released mineral nitrogen coming from crushed catch crop on N2O production if summer crop seedling and mineral nitrogen release are not well synchronized. To verify those assumptions, a unique paired-plot experiment was carried in the south-west of France from September 2013 to august 2014 to test impact of management change on N2O budget and production dynamic. A crop plot was divided into two subplots, one receiving a catch crop (mustard), the other one remaining conventionally managed (bare-soil during winter). This set-up allowed avoiding climate effect. Each subplot was

  6. Arylsulphatase activity and sulphate content in relation to crop rotation and fertilization of soil

    Science.gov (United States)

    Siwik-Ziomek, Anetta; Lemanowicz, Joanna; Koper, Jan

    2016-07-01

    The aim of the study was to investigate the effect of varying rates of FYM (0, 20, 40, 60 Mg ha-1) and nitrogen N0, N1, N2, and N3 on the content of sulphate sulphur (VI) and the activity of arylsulphatase, which participates in the transformations of this element in Haplic Luvisol. The study report is based on a long-term field experiment with two different crop rotations: A - recognized as exhausting the humus from soil and B - recognized as enriching the soil with humus. During the cultivation of the plants, the soil was sampled four times from corn and a red clover cultivar and grass. The FYM fertilization rate for which the highest arylsulphatase activity and the content of sulphates were identified was 60 Mg ha-1. An inhibitory effect of high rates (90 and 135 kg N ha-1) of ammonium nitrate on the arylsulphatase activity was also observed. A significant correlation between the content of carbon, nitrogen, and sulphates and the arylsulphatase activity was recorded. The investigation on the effect of combined application of farmyard manure and mineral nitrogen fertilization on the activity of arylsulphatase participating in the sulphur cycling was launched to examine the problem in detail.

  7. The full GHG balance over two crop rotations at an agricultural site near Gebesee, Thuringia, Germany

    Science.gov (United States)

    Kutsch, Werner Leo; Brümmer, Christian; Don, Catharina; Dechow, Rene; Fuß, Roland; Freibauer, Annette; Schulze, Ernst-Detlef; Kolle, Olaf; Ziegler, Waldemar

    2013-04-01

    Gebesee in Thuringia is the eldest cropland eddy covariance (EC) site in Europe. The site has been part of CarboEurope, NitroEurope and IMECC and has been selected to be one of the German Level 1 sites within the European research infrastructure ICOS. Continuous measurements of NEE by EC, NPP by regular harvesting, lateral in- and outputs of carbon and nitrogen as well as climatic parameters have been conducted since 2001. Automated chamber measurements of N2O and CH4 were conducted since 2007. Fluxes of these greenhouse gases (GHG) for the years 2001 - 2006 were calculated based on a Fuzzy Logic model calibrated by means of the chamber measurements. In this study we present NEE, NBP and full GHG balances of over two rotation periods (2001 - 2004 and 2005 - 2009, respectively) comprising four times winter wheat, two times potatoes and one cropping period of oil seed rape, sugar beet and barley each. The GHG balance is dominated by moderate losses of soil organic matter (~120 +/- 50 g C m-2 y-1) and by N2O emissions of about 0.17 g N2O-N m-2 y-1 (50 g C-eq m-2 y-1). The on-site emissions of GHG balance about 43 % of the harvested carbon.

  8. Environmental effects of growing short-rotation woody crops on former agricultural lands

    Energy Technology Data Exchange (ETDEWEB)

    Tolbert, V.R. [Oak Ridge National Lab., TN (United States); Thornton, F.C.; Joslin, J.D. [Tennessee Valley Authority, Muscle Shoals, AL (United States). Atmospheric Sciences Div.] [and others

    1997-10-01

    Field-scale studies in the Southeast have been addressing the environmental effects of converting agricultural lands to biomass crop production since 1994. Erosion, surface water quality and quantity and subsurface movement of water and nutrients from woody crops, switchgrass and agricultural crops are being compared. Nutrient cycling, soil physical changes and crop productivity are also being monitored at the three sites. Maximum sediment losses occurred in the spring and fall. Losses were greater from sweetgum planted without a cover crop than with a cover crop. Nutrient losses of N and P in runoff and subsurface water occurred primarily after spring fertilizer application.

  9. Soil Management Practices to Improve Nutrient-use Efficiencies and Reduce Risk in Millet-based Cropping Systems in the Sahel

    Directory of Open Access Journals (Sweden)

    Koala, S.

    2003-01-01

    Full Text Available Low soil fertility and moisture deficit are among the main constraints to sustainable crop yields in the Sahel. A study therefore, was conducted at the ICRISAT Sahelian Center, Sadore in Niger to test the hypothesis that integrated soil husbandry practices consisting of manure, fertilizer and crop residues in rotational cropping systems use organic and mineral fertilizes efficiently, thereby resulting in higher yields and reduced risk. Results from an analysis of variance showed that choice of cropping systems explained more than 50% of overall variability in millet and cowpea grain yields. Among the cropping systems, rotation gave higher yields than sole crop and intercropping systems and increased millet yield by 46% without fertilizer. Rainfall-use efficiency and partial factor productivity of fertilizer were similarly higher in rotations than in millet monoculture system. Returns from cowpea grown in cowpea-millet rotation without fertilizer and the medium rates of fertilizers (4 kg P.ha-1 + 15 kg N.ha-1 were found to be most profitable in terms of high returns and low risk, principally because of a higher price of cowpea than millet. The study recommends crop diversification, either in the form of rotations or relay intercropping systems for the Sahel as an insurance against total crop failure.

  10. Grazing management in an integrated crop-livestock system: soybean development and grain yield

    Directory of Open Access Journals (Sweden)

    Taise Robinson Kunrath

    Full Text Available ABSTRACTGrazing livestock in integrated crop-livestock systems can cause impacts in the subsequent crop cycle. Aiming to investigate how grazing could affect soybean, the 9th crop cycle of a pasture/soybean rotation was assessed. Treatments were grazing intensities (10, 20, 30 and 40 cm of sward height applied since 2001 in a mixed of oat and annual ryegrass; and an additional no grazing area as control. Treatments were arranged in a completely randomized block design with three replicates. Grazing affected soybean population and the mass of individual nodules (P0.05. Soybean yield showed differences among treatments, but no difference was found between grazed and non-grazed areas. Grazing intensities impact the coverage and frequency of weeds (P>0.05. In conclusion, grazing intensity impacts different parameters of soybean yield and development, but only the grazing intensity of 10 cm can jeopardize the succeeding soybean crop.

  11. Cropping system effects on wind erosion potential

    Science.gov (United States)

    Wind erosion of soil is a destructive process impacting crop productivity and human health and safety. The mechanics of wind erosion and soil properties that influence erosion are well understood. Less well-studied are the effects that cropping intensity has upon those soil properties. We collected ...

  12. An estimation of annual nitrous oxide emissions and soil quality following the amendment of high temperature walnut shell biochar and compost to a small scale vegetable crop rotation.

    Science.gov (United States)

    Suddick, Emma C; Six, Johan

    2013-11-01

    Agricultural soils are responsible for emitting large quantities of nitrous oxide (N2O). The controlled incomplete thermal decomposition of agricultural wastes to produce biochar, once amended to soils, have been hypothesized to increase crop yield, improve soil quality and reduce N2O emissions. To estimate crop yields, soil quality parameters and N2O emissions following the incorporation of a high temperature (900 °C) walnut shell (HTWS) biochar into soil, a one year field campaign with four treatments (control (CONT), biochar (B), compost (COM), and biochar+compost (B+C)) was conducted in a small scale vegetable rotation system in Northern California. Crop yields from five crops (lettuce, winter cover crop, lettuce, bell pepper and Swiss chard) were determined; there were no significant differences in yield between treatments. Biochar amended soils had significant increases in % total carbon (C) and the retention of potassium (K) and calcium (Ca). Annual cumulative N2O fluxes were not significantly different between the four treatments with emissions ranging from 0.91 to 1.12 kg N2O-N ha(-1) yr(-1). Distinct peaks of N2O occurred upon the application of N fertilizers and the greatest mean emissions, ranging from 67.04 to 151.41 g N2O-N ha(-1) day(-1), were observed following the incorporation of the winter cover crop. In conclusion, HTWS biochar application to soils had a pronounced effect on the retention of exchangeable cations such as K and Ca compared to un-amended soils and composted soils, which in turn could reduce leaching of these plant available cations and could thus improve soils with poor nutrient retention. However, HTWS biochar additions to soil had neither a positive or negative effect on crop yield nor cumulative annual emissions of N2O.

  13. Crop rotations with annual and perennial forages under no-till soil management: soil attributes, soybean mineral nutrition, and yield

    Science.gov (United States)

    Extensive use of sustainable and intensive agricultural systems would result in profitable farms producing greater yields while maintaining or enhancing natural resources. Development of sustainable crop and soil management systems depends on understanding complex relationships between soil managem...

  14. Optimization of Korean crop storage insulation systems

    Energy Technology Data Exchange (ETDEWEB)

    Jongho Yoon [Taejon National Univ. of Technology, Dept. of Architectural Engineering, Taejon (Korea); Euyjoon Lee [Korea Inst. of Energy Research, Passive Solar Research Team, Taejon (Korea); Krarti, Moncef [Colorado Univ., CEAE Dept., Boulder, CO (United States)

    2003-05-01

    With the increasing concerns with the quality and the safety of foods, several standards and guidelines have been developed to improve the design, construction and operation of storage warehouses. Several cool storage buildings have been constructed in Korea during the last decade. However, there are no specific standards or guidelines for energy use reduction in refrigerated structures. The main objective of this study is to determine the impact of various insulation systems on the total cooling load of the cool storage structures with particular consideration given to the product thermal mass to find optimal insulation thicknesses for each envelope component for various climatic locations in Korea. An energy analysis model was developed using the DOE-2.1E program. To determine the optimal configuration for the storage building insulation system, life cycle cost analysis was conducted. The selection of optimal insulation configuration for each climatic location is based on various criteria including cost and energy minimization. The results presented in this paper provide easy to use design guidelines to select the optimal insulation thickness for crop storage facilities in Korea. (Author)

  15. European Perspectives on the Adoption of Non-Chemical Weed Management in Reduced Tillage Systems for Arable Crops

    DEFF Research Database (Denmark)

    Melander, B.; Munier-Jolan, N.; Schwarz, J.

    2012-01-01

    expansion of reduced tillage systems. European agriculture is asked to become less dependent on pesticide use and promote crop protection programmes based on integrated pest management (IPM) principles. Non-inversion tillage systems rely entirely on the availability of glyphosate products and herbicide...... consumption appears to be slightly higher as compared to plough based cropping systems. Annual grass weeds and stickywilly often constitute the principal weed problems when the soil is not inverted because crop rotations concurrently have very high proportions of winter cereals. There is a need to redesign...

  16. The Role of Crop Systems Simulation in Agriculture and Environment

    Science.gov (United States)

    Over the past 30 to 40 years, simulation of crop systems has advanced from a neophyte science with inadequate computing power into a robust and increasingly accepted science supported by improved software, languages, development tools, and computer capabilities. Crop system simulators contain mathe...

  17. Crops Rotation – the Solution of Environmental Problems (a Case Study of Prince Edward Island in Canada

    Directory of Open Access Journals (Sweden)

    P. Procházka

    2015-09-01

    Full Text Available Prince Edward Island (PEI is well known around the world for its potato industry. While economically beneficial for PEI, potato production contributes to its environmental deterioration. This can be attributed to the high use of chemicals and fertilizers in the production, which leads to the pollution of PEI’s watercourses. In response to the environmental crisis, the PEI provincial government proposed several land use policies to mitigate the negative influence of potato production on water quality. One of the policies that is analyzed in this paper is a mandated crop rotation. The analysis of the mandatory crop rotation policy is achieved through the application of optimal control theory and dynamic programming. Findings from the co-integration model show that agriculture is most likely responsible for watercourse pollution in PEI. This provides statistical evidence that a policy aimed at water protection, specifically targeting potato land use is necessary. However the application of environmentally friendly approach (mandatory crops rotation is positive, its negative impact on individual farms economy is evident.

  18. Modelling of nitrogen leaching under a complex winter wheat and red clover crop rotation in a drained agricultural field

    Science.gov (United States)

    Conrad, Y.; Fohrer, N.

    The European Water Framework Directive requires conformity of water management structures all over Europe to pursue a good water quality for all water bodies. The highest nitrate concentrations in the water were measured in regions with well-drained soils, ploughed pastures and high nitrogen inputs. The objective of this study was to calculate the nitrate nitrogen leaching out of a subsurface drainage system under organic farming conditions, especially for the seepage period in winter. Water and nitrogen fluxes between soil and vegetation were simulated with the soil-vegetation-atmosphere-transfer model CoupModel using data from an 8 years lasting monitoring programme on a field in Northern Germany. Modelling was focused on a crop rotation sequence consisting of winter wheat with undersown red clover followed by two years of red clover used as temporary grassland. Measured soil temperature in a depth of 15 cm was reproduced very well (Nash-Sutcliffe-efficiency NSE = 0.95; R2 = 0.98). Results also indicated that CoupModel accurately simulated drainage discharge and nitrate N loss under winter wheat from 2001 to 2002 with a NSE of 0.73 for the drainage discharge and a NSE of 0.49 for the nitrate N leaching. For the following red clover period the accordance between simulated and measured drainage discharge (NSE = 0.01) and nitrate N loads in the drainage (NSE = 0.31) was much lower. The inaccuracy in the modelling results in November 2002 seems to origin from an inadequate description of soil covering and thus the interception of the hibernating red clover. Secondly, the high nitrogen leaching in February 2004 could not be matched due to poorly adapted nitrogen dynamics in the model. The reason could be that common single parameter values in the mineralization part of the model were not suitable to reproduce an abrupt, short-term N leaching. In general, the results demonstrate the potential of CoupModel to predict water and nitrate N fluxes under complex crop

  19. A low frequency rotational energy harvesting system

    Science.gov (United States)

    Febbo, M.; Machado, S. P.; Ramirez, J. M.; Gatti, C. D.

    2016-11-01

    This paper presents a rotary power scavenging unit comprised of two systems of flexible beams connected by two masses which are joined by means of a spring, considering a PZT (QP16N, Midé Corporation) piezoelectric sheet mounted on one of the beams. The energy harvesting (EH) system is mounted rigidly on a rotating hub. The gravitational force on the masses causes sustained oscillatory motion in the flexible beams as long as there is rotary motion. The intention is to use the EH system in the wireless autonomous monitoring of wind turbines under different wind conditions. Specifically, the development is oriented to monitor the dynamic state of the blades of a wind generator of 30 KW which rotates between 50 and 150 rpm. The paper shows a complete set of experimental results on three devices, modifying the amount of beams in the frame supporting the system. The results show an acceptable sustained voltage generation for the expected range, in the three proposed cases. Therefore, it is possible to use this system for generating energy in a low-frequency rotating environment. As an alternative, the system can be easily adapted to include an array of piezoelectric sheets to each of the beams, to provide more power generation.

  20. Cultivation-Based and Molecular Assessment of Bacterial Diversity in the Rhizosheath of Wheat under Different Crop Rotations.

    Directory of Open Access Journals (Sweden)

    Muhammad Tahir

    Full Text Available A field study was conducted to compare the formationand bacterial communities of rhizosheaths of wheat grown under wheat-cotton and wheat-rice rotation and to study the effects of bacterial inoculation on plant growth. Inoculation of Azospirillum sp. WS-1 and Bacillus sp. T-34 to wheat plants increased root length, root and shoot dry weight and dry weight of rhizosheathsoil when compared to non-inoculated control plants, and under both crop rotations. Comparing both crop rotations, root length, root and shoot dry weight and dry weight of soil attached with roots were higher under wheat-cotton rotation. Organic acids (citric acid, malic acid, acetic acid and oxalic acid were detected in rhizosheaths from both rotations, with malic acid being most abundant with 24.8±2 and 21.3±1.5 μg g(-1 dry soil in wheat-cotton and wheat-rice rotation, respectively. Two sugars (sucrose, glucose were detected in wheat rhizosheath under both rotations, with highest concentrations of sucrose (4.08±0.5 μg g(-1 and 7.36±1.0 μg g(-1 and glucose (3.12±0.5 μg g(-1 and 3.01± μg g(-1 being detected in rhizosheaths of non-inoculated control plants under both rotations. Diversity of rhizosheath-associated bacteria was evaluated by cultivation, as well as by 454-pyrosequencing of PCR-tagged 16S rRNA gene amplicons. A total of 14 and 12 bacterial isolates predominantly belonging to the genera Arthrobacter, Azospirillum, Bacillus, Enterobacter and Pseudomonaswere obtained from the rhizosheath of wheat grown under wheat-cotton and wheat-rice rotation, respectively. Analysis of pyrosequencing data revealed Proteobacteria, Bacteriodetes and Verrucomicrobia as the most abundant phyla in wheat-rice rotation, whereas Actinobacteria, Firmicutes, Chloroflexi, Acidobacteria, Planctomycetes and Cyanobacteria were predominant in wheat-cotton rotation. From a total of 46,971 sequences, 10.9% showed ≥97% similarity with 16S rRNA genes of 32 genera previously shown to include

  1. Atributos bioquímicos e químicos do solo rizosférico e não rizosférico de culturas em rotação no sistema de semeadura direta Biochemical and chemical attributes of rhizospheric and non-rhizospheric soil in no till crop rotation system

    Directory of Open Access Journals (Sweden)

    Meire Aparecida Silvestrini Cordeiro

    2012-12-01

    improvement of organic matter in the soil. In addition, the plants constituents of these systems produce the rhizospheric effect through the influence zone of the roots, increasing activity and modifying the microbial population. The objective of this study was to evaluate the effect of winter crop rotation and summer crop sequences in a no tillage system, based on biochemical (amylase, urease, cellulase, and protease and chemical (organic carbon, total carbohydrates, and total protein characteristics in rhizospheric (SR and non-rhizospheric soil (SNR. Three winter crops were studied: corn (Zea mays L., sunflower (Helianthus anuus L., and pigeon pea (Cajanus cajan (L. Millsp, in rotation with three summer sequences: soybean/soybean (Glycine max L., corn/corn, and soybean/corn. Samples were taken from soil adhering to the plant roots (SR and from in-between the rows (SNR. The activities of amylase, cellulase, protease, and urease in SR were 16, 85, 62, and 100 % higher, respectively, than in SNR. For total organic carbon and total protein, the difference was 21 %. Of the winter crops, corn stimulated higher amylase, cellulase, protease, and urease activity in SR, as well as amylase, protease, and urease activity in SNR. The winter crops and the summer sequences did not affect total protein levels. The total carbohydrates were influenced by winter corn and sunflower crops. Only the summer corn/corn sequence influenced total organic carbon. The biochemical and chemical properties analyzed in this study can be used as indicators of changes in soil caused by winter crops and summer sequences.

  2. A multi-adaptive framework for the crop choice in paludicultural cropping systems

    Directory of Open Access Journals (Sweden)

    Nicola Silvestri

    2017-03-01

    Full Text Available The conventional cultivation of drained peatland causes peat oxidation, soil subsidence, nutrient loss, increasing greenhouse gas emissions and biodiversity reduction. Paludiculture has been identified as an alternative management strategy consisting in the cultivation of biomass on wet and rewetted peatlands. This strategy can save these habitats and restore the ecosystem services provided by the peatlands both on the local and global scale. This paper illustrates the most important features to optimise the crop choice phase which is the crucial point for the success of paludiculture systems. A multi-adaptive framework was proposed. It was based on four points that should be checked to identify suitable crops for paludicultural cropping system: biological traits, biomass production, attitude to cultivation and biomass quality. The main agronomic implications were explored with the help of some results from a plurennial open-field experimentation carried out in a paludicultural system set up in the Massaciuccoli Lake Basin (Tuscany, Italy and a complete example of the method application was provided. The tested crops were Arundo donax L., Miscanthus×giganteus Greef et Deuter, Phragmites australis L., Populus×canadensis Moench. and Salix alba L. The results showed a different level of suitability ascribable to the different plant species proving that the proposed framework can discriminate the behaviour of tested crops. Phragmites australis L. was the most suitable crop whereas Populus×canadensis Moench and Miscanthus×giganteus Greef et Deuter (in the case of biogas conversion occupied the last positions in the ranking.

  3. Effect of a 5-Year Multi-Crop Rotation on Mineral N and Hard Red Spring Wheat Yield, Protein, Test Weight and Economics in Western North Dakota, USA

    Science.gov (United States)

    Landblom, Douglas; Senturklu, Songul; Cihacek, Larry; Brevik, Eric

    2016-04-01

    The objectives of this non-irrigated cropping study was to employ the principles of soil health and determine the effect of rotation on seasonal mineral N, HRSW production, protein, test weight, and economics. Prior to the initiation of this research, the cropping study area had been previously seeded to hard red spring wheat (HRSW). The cropping systems consisted of a continuous HRSW control (C) compared to HRSW grown in a multi-crop 5-year rotation (R). The 5-yr rotation consisted of HRSW, cover crop (dual crop winter triticale-hairy vetch harvested for hay in June and immediately reseeded to a 7-species cover crop mix grazed by cows after weaning from mid-November to mid-December), forage corn, field pea-forage barley, and sunflower. The cereal grains, cover crops, and pea-barley intercrop were seeded using a JD 1590 no-till drill, 19 cm row spacing, and seed depth of 2.54 cm Cereal grain plant population was 3,088,750 plants/ha. The row crops were planted using a JD 7000 no-till planter, 76.2 cm row spacing, and seed depth of 5.08 cm. Plant population for the row crops was 46,947 plants/ha. Weeds were controlled using a pre-plant burn down and post-emergence control except for cover crops and pea-barley where a pre-plant burn down was the only chemical applied. Fertilizer application was based on soil test results and recommendations from the North Dakota State University Soil Testing Laboratory. During the 1st three years of the study 31.8 kg of N was applied to the C HRSW and then none the last two years of the 5-year period. The R HRSW was fertilized with 13.6 kg of N the 1st two years of the study and none the remaining three years of the 5-year period. However, chloride was low; therefore, 40.7-56.1 kg/ha were applied each year to both the C and R treatments. Based on 2014 and 2015 seasonal mineral N values, the data suggests that N levels were adequate to meet the 2690 kg/ha yield goal. In 2015, however, the R yield goal was exceeded by 673 kg/ha whereas

  4. Rotating Machinery Predictive Maintenance Through Expert System

    Directory of Open Access Journals (Sweden)

    M. Sarath Kumar

    2000-01-01

    Full Text Available Modern rotating machines such as turbomachines, either produce or absorb huge amount of power. Some of the common applications are: steam turbine-generator and gas turbine-compressor-generator trains produce power and machines, such as pumps, centrifugal compressors, motors, generators, machine tool spindles, etc., are being used in industrial applications. Condition-based maintenance of rotating machinery is a common practice where the machine's condition is monitored constantly, so that timely maintenance can be done. Since modern machines are complex and the amount of data to be interpreted is huge, we need precise and fast methods in order to arrive at the best recommendations to prevent catastrophic failure and to prolong the life of the equipment. In the present work using vibration characteristics of a rotor-bearing system, the condition of a rotating machinery (electrical rotor is predicted using an off-line expert system. The analysis of the problem is carried out in an Object Oriented Programming (OOP framework using the finite element method. The expert system which is also developed in an OOP paradigm gives the type of the malfunctions, suggestions and recommendations. The system is implemented in C++.

  5. Effects of Monoculture, Crop Rotation, and Soil Moisture Content on Selected Soil Physicochemical and Microbial Parameters in Wheat Fields

    Directory of Open Access Journals (Sweden)

    A. Marais

    2012-01-01

    Full Text Available Different plants are known to have different soil microbial communities associated with them. Agricultural management practices such as fertiliser and pesticide addition, crop rotation, and grazing animals can lead to different microbial communities in the associated agricultural soils. Soil dilution plates, most-probable-number (MPN, community level physiological profiling (CLPP, and buried slide technique as well as some measured soil physicochemical parameters were used to determine changes during the growing season in the ecosystem profile in wheat fields subjected to wheat monoculture or wheat in annual rotation with medic/clover pasture. Statistical analyses showed that soil moisture had an over-riding effect on seasonal fluctuations in soil physicochemical and microbial populations. While within season soil microbial activity could be differentiated between wheat fields under rotational and monoculture management, these differences were not significant.

  6. BIRKHOFF'S EQUATIONS AND GEOMETRICAL THEORY OF ROTATIONAL RELATIVISTIC SYSTEM

    Institute of Scientific and Technical Information of China (English)

    LUO SHAO-KAI; CHEN XIANG-WEI; FU JING-LI

    2001-01-01

    The Birkhoffian and Birkhoff's functions of a rotational relativistic system are constructed, the Pfaff action of rotational relativistic system is defined, the Pfaff-Birkhoff principle of a rotational relativistic system is given, and the Pfaff-Birkhoff-D'Alembert principles and Birkhoff's equations of rotational relativistic system are constructed. The geometrical description of a rotational relativistic system is studied, and the exact properties of Birkhoff's equations and their forms onR × T*M for a rotational relativistic system are obtained. The global analysis of Birkhoff's equations for a rotational relativistic system is studied, the global properties of autonomous, semi-autonomous and non-autonomous rotational relativistic Birkhoff's equations, and the geometrical properties of energy change for rotational relativistic Birkhoff's equations are given.

  7. The Effects of Winter Cover Crops and Plant Growth Promoting Rhizobacteria on some Soil Fertility Aspects and Crop Yield in an Organic Production System of Ocimum basilicum L.

    Directory of Open Access Journals (Sweden)

    M Jahan

    2014-03-01

    Full Text Available Sustainable agriculture systems emphasized on the on-farm inputs likes use of biofertilizers, crop rotation and cover crops. This experiment was conducted in a split plots arrangement with two factors based on randomized complete block design with three replications during years 2009-2010, at Research Farm of Ferdowsi University of Mashhad. The main factor consisted of cultivation and no cultivation of cover crops in autumn. The sub factor was biofertilizer application with four levels, included 1-Nitroxin® (containing Azotobacter spp. and Azospirillum spp., 2-Biophosphorous® (Bacillus sp. and Pseudomonas sp., 3-Nitroxin® + Biophosphorous® and 4-Control. Results showed that most characteristics, e.g. seed yield and harvest index were increased with no cover crop cultivation. However in control treatment, the biological yield, seed yield and harvest index were more than biofertilizeres treatments, as Nitroxin® and Biophosphorous® ranked after the control. Amongst the biofertilizers, Biophosphorus® had the most positive effects. The maximum grain weight was obtained from Nitroxin®+ Biophosphorous® treatment. The interaction effects of biofertilizer and cover crops were significant among some characteristics. The results showed that the interaction between biofertilizers and no cover crop cultivation was significant, as use of the biofertilizers especially Nitroxin® and Biophosphorous® in no cover crop condition increased the amounts of biological yield and seed yield.

  8. Nitrate leaching and residual effect in dairy crop rotations with grass-clover leys as influenced by sward age, grazing, cutting and fertilizer regimes

    DEFF Research Database (Denmark)

    Eriksen, Jørgen; Askegaard, Margrethe; Rasmussen, Jim;

    2015-01-01

    Intensive dairy farming, with grass-arable crop rotations is challenged by low N use efficiency that may have adverse environmental consequences. We investigated nitrate leaching and N fertility effects of grass–clover leys for five years in two organic crop rotations with different grassland...... proportions (33 and 67%) and five grassland managements in terms of cutting, grazing, fertilization and combinations thereof. In grass–clover, the combination of fertilization and grazing caused excessive leaching (average 60 kg N ha−1) but leaving out either fertilization or full-time grazing substantially...... and fertilization and lowest without fertilization or cutting-only management and was not influenced by grassland age. The arable part of the mixed crop rotation was nitrate leaky where crop coverage in autumn was insufficient. Nitrate leaching following the crops may roughly be divided into four groups: (1) low...

  9. Integrating Sunflower Oil Seed Crops into Florida Horticultural Production Systems

    Science.gov (United States)

    Locally produced biodiesel feedstock plant oil creates a unique possibility to integrate multiple-goal oriented cover crops into Florida horticultural production systems. Typically, cover crops are planted to improve soil fertility and the natural suppression of soilborne pests at times when fields...

  10. Impacts of Watershed Characteristics and Crop Rotations on Winter Cover Crop Nitrate-Nitrogen Uptake Capacity within Agricultural Watersheds in the Chesapeake Bay Region.

    Science.gov (United States)

    Lee, Sangchul; Yeo, In-Young; Sadeghi, Ali M; McCarty, Gregory W; Hively, W Dean; Lang, Megan W

    2016-01-01

    The adoption rate of winter cover crops (WCCs) as an effective conservation management practice to help reduce agricultural nutrient loads in the Chesapeake Bay (CB) is increasing. However, the WCC potential for water quality improvement has not been fully realized at the watershed scale. This study was conducted to evaluate the long-term impact of WCCs on hydrology and NO3-N loads in two adjacent watersheds and to identify key management factors that affect the effectiveness of WCCs using the Soil and Water Assessment Tool (SWAT) and statistical methods. Simulation results indicated that WCCs are effective for reducing NO3-N loads and their performance varied based on planting date, species, soil characteristics, and crop rotations. Early-planted WCCs outperformed late-planted WCCs on the reduction of NO3-N loads and early-planted rye (RE) reduced NO3-N loads by ~49.3% compared to the baseline (no WCC). The WCCs were more effective in a watershed dominated by well-drained soils with increased reductions in NO3-N fluxes of ~2.5 kg N·ha-1 delivered to streams and ~10.1 kg N·ha-1 leached into groundwater compared to poorly-drained soils. Well-drained agricultural lands had higher transport of NO3-N in the soil profile and groundwater due to increased N leaching. Poorly-drained agricultural lands had lower NO3-N due to extensive drainage ditches and anaerobic soil conditions promoting denitrification. The performance of WCCs varied by crop rotations (i.e., continuous corn and corn-soybean), with increased N uptake following soybean crops due to the increased soil mineral N availability by mineralization of soybean residue compared to corn residue. The WCCs can reduce N leaching where baseline NO3-N loads are high in well-drained soils and/or when residual and mineralized N availability is high due to the cropping practices. The findings suggested that WCC implementation plans should be established in watersheds according to local edaphic and agronomic

  11. Impacts of Watershed Characteristics and Crop Rotations on Winter Cover Crop Nitrate-Nitrogen Uptake Capacity within Agricultural Watersheds in the Chesapeake Bay Region.

    Directory of Open Access Journals (Sweden)

    Sangchul Lee

    Full Text Available The adoption rate of winter cover crops (WCCs as an effective conservation management practice to help reduce agricultural nutrient loads in the Chesapeake Bay (CB is increasing. However, the WCC potential for water quality improvement has not been fully realized at the watershed scale. This study was conducted to evaluate the long-term impact of WCCs on hydrology and NO3-N loads in two adjacent watersheds and to identify key management factors that affect the effectiveness of WCCs using the Soil and Water Assessment Tool (SWAT and statistical methods. Simulation results indicated that WCCs are effective for reducing NO3-N loads and their performance varied based on planting date, species, soil characteristics, and crop rotations. Early-planted WCCs outperformed late-planted WCCs on the reduction of NO3-N loads and early-planted rye (RE reduced NO3-N loads by ~49.3% compared to the baseline (no WCC. The WCCs were more effective in a watershed dominated by well-drained soils with increased reductions in NO3-N fluxes of ~2.5 kg N·ha-1 delivered to streams and ~10.1 kg N·ha-1 leached into groundwater compared to poorly-drained soils. Well-drained agricultural lands had higher transport of NO3-N in the soil profile and groundwater due to increased N leaching. Poorly-drained agricultural lands had lower NO3-N due to extensive drainage ditches and anaerobic soil conditions promoting denitrification. The performance of WCCs varied by crop rotations (i.e., continuous corn and corn-soybean, with increased N uptake following soybean crops due to the increased soil mineral N availability by mineralization of soybean residue compared to corn residue. The WCCs can reduce N leaching where baseline NO3-N loads are high in well-drained soils and/or when residual and mineralized N availability is high due to the cropping practices. The findings suggested that WCC implementation plans should be established in watersheds according to local edaphic and agronomic

  12. Influence of crop rotation and meteorological conditons on density and biomass of weeds in spring barley (Hordeum vulgare L.

    Directory of Open Access Journals (Sweden)

    Maria Wanic

    2012-12-01

    Full Text Available The paper presents the analysis of changes in weed infestation in spring barley cultivated in the years 1990-2004 in crop rotation with a 25% proportion of this cereal (potato - spring barley - sowing peas - winter triticale, when it was grown after potato, and in crop rotation with its 75% proportion (potato - spring barley - spring barley - spring barley, when it was grown once or twice after spring barley. In the experiment, no weed control was applied. Every year in the spring (at full emergence of the cereal and before the harvest, the composition of weed species and weed density of particular weed species were determined, and before the harvest also their biomass. Weed density increased linearly on all plots during the 15-year period. The average values confirm the increase in weed biomass in the case when spring barley was grown once or twice after this crop; however, those differences were influenced by the previous situation only during some seasons. Weed density and biomass showed high year-to-year variability and a positive correlation with the amount of precipitation and a negative correlation with temperature during the period of the study. A negative correlation between the yield of barley and weed biomass was shown.

  13. Crop candidates for the bioregenerative life support systems in China

    Science.gov (United States)

    Chunxiao, Xu; Hong, Liu

    The use of plants for life support applications in space is appealing because of the multiple life support functions by the plants. Research on crops that were grown in the life support system to provide food and oxygen, remove carbon dioxide was begun from 1960. To select possible crops for research on the bioregenerative life support systems in China, criteria for the selection of potential crops were made, and selection of crops was carried out based on these criteria. The results showed that 14 crops including 4 food crops (wheat, rice, soybean and peanut) and 7 vegetables (Chinese cabbage, lettuce, radish, carrot, tomato, squash and pepper) won higher scores. Wheat ( Triticum aestivum L.), rice ( Oryza sativa L.), soybean ( Glycine max L.) and peanut ( Arachis hypogaea L.) are main food crops in China. Chinese cabbage ( Brassica campestris L. ssp. chinensis var. communis), lettuce ( Lactuca sativa L. var. longifolia Lam.), radish ( Raphanus sativus L.), carrot ( Daucus carota L. var. sativa DC.), tomato ( Lycopersicon escalentum L.), squash ( Cucurbita moschata Duch.) and pepper ( Capsicum frutescens L. var. longum Bailey) are 7 vegetables preferred by Chinese. Furthermore, coriander ( Coriandum sativum L.), welsh onion ( Allium fistulosum L. var. giganteum Makino) and garlic ( Allium sativum L.) were selected as condiments to improve the taste of space crew. To each crop species, several cultivars were selected for further research according to their agronomic characteristics.

  14. Crop residue management in arable cropping systems under a temperate climate. Part 2: Soil physical properties and crop production. A review

    Directory of Open Access Journals (Sweden)

    Hiel, MP.

    2016-01-01

    Full Text Available Introduction. Residues of previous crops provide a valuable amount of organic matter that can be used either to restore soil fertility or for external use. A better understanding of the impact of crop residue management on the soil-water-plant system is needed in order to manage agricultural land sustainably. This review focuses on soil physical aspects related to crop residue management, and specifically on the link between soil structure and hydraulic properties and its impact on crop production. Literature. Conservation practices, including crop residue retention and non-conventional tillage, can enhance soil health by improving aggregate stability. In this case, water infiltration is facilitated, resulting in an increase in plant water availability. Conservation practices, however, do not systematically lead to higher water availability for the plant. The influence of crop residue management on crop production is still unclear; in some cases, crop production is enhanced by residue retention, but in others crop residues can reduce crop yield. Conclusions. In this review we discuss the diverse and contrasting effects of crop residue management on soil physical properties and crop production under a temperate climate. The review highlights the importance of environmental factors such as soil type and local climatic conditions, highlighting the need to perform field studies on crop residue management and relate them to specific pedo-climatic contexts.

  15. Using the DNDC model to compare soil organic carbon dynamics under different crop rotation and fertilizer strategies

    Directory of Open Access Journals (Sweden)

    Lan Mu

    2014-02-01

    Full Text Available Soil organic carbon (SOC plays a vital role in determining soil fertility, water holding capacity and susceptibility to land degradation. On the Chinese Loess Plateau, a large amount of crop residues is regularly removed; therefore, this agricultural area mainly depends on fertilizer inputs to maintain crop yields. This paper aims to use a computer simulation model (DeNitrification and DeComposition, or DNDC to estimate the changes of SOC content and crop yield from 1998 to 2047 under different cropping systems, providing some strategies to maintain the SOC in balance and to increase crop yields. The results demonstrated that: (i single manure application or combined with nitrogen fertilizer could significantly enhance the SOC content and crop yield on the sloped land, terraced field and flat land; and (ⅱ in contrast to sloped land and terraced field, the SOC content and crop yield both continuously increased in flat fields, indicating that the flat field in this region is a good soil surface for carbon sequestration. These results emphasize that application of manure combined with nitrogen fertilizer would be a better management practice to achieve a goal of increasing soil carbon sequestration and food security.

  16. Using the DNDC model to compare soil organic carbon dynamics under different crop rotation and fertilizer strategies

    Energy Technology Data Exchange (ETDEWEB)

    Mu, L.; Liang, Y.; Xue, Q.; Chen, C.; Lin, X.

    2014-06-01

    Soil organic carbon (SOC) plays a vital role in determining soil fertility, water holding capacity and susceptibility to land degradation. On the Chinese Loess Plateau, a large amount of crop residues is regularly removed; therefore, this agricultural area mainly depends on fertilizer inputs to maintain crop yields. This paper aims to use a computer simulation model (DeNitrification and DeComposition, or DNDC) to estimate the changes of SOC content and crop yield from 1998 to 2047 under different cropping systems, providing some strategies to maintain the SOC in balance and to increase crop yields. The results demonstrated that: (i) single manure application or combined with nitrogen fertilizer could significantly enhance the SOC content and crop yield on the sloped land, terraced field and flat land; and (ii) in contrast to sloped land and terraced field, the SOC content and crop yield both continuously increased in flat fields, indicating that the flat field in this region is a good soil surface for carbon sequestration. These results emphasize that application of manure combined with nitrogen fertilizer would be a better management practice to achieve a goal of increasing soil carbon sequestration and food security. (Author)

  17. Models of cuspy triaxial stellar systems. IV: Rotating systems

    CERN Document Server

    Carpintero, D D

    2016-01-01

    We built two self-consistent models of triaxial, cuspy, rotating stellar systems adding rotation to non-rotating models presented in previous papers of this series. The final angular velocity of the material is not constant and varies with the distance to the center and with the height over the equator of the systems, but the figure rotation is very uniform in both cases. Even though the addition of rotation to the models modifies their original semiaxes ratios, the final rotating models are considerably flattened and triaxial. An analysis of the orbital content of the models shows that about two thirds of their orbits are chaotic yet the models are very stable over intervals of the order of one Hubble time. The bulk of regular orbits are short axis tubes, while long axis tubes are replaced by tubes whose axes lie on the short-long axes plane, but do not coincide with the major axis. Other types of regular orbits that do not appear in non-rotating systems, like horseshoes and orbits that cross themselves, are...

  18. A rotational framework to reduce weed density in organic systems

    Science.gov (United States)

    Weeds are a major obstacle to successful crop production in organic farming. Producers may be able to reduce inputs for weed management by designing rotations to disrupt population dynamics of weeds. Population-based management in conventional farming has reduced herbicide use 50% because weed den...

  19. Characteristics of C and N Accumulation in Infertile Red Soil Under Different Rotation Systems

    Institute of Scientific and Technical Information of China (English)

    LI Zhong-pei; TANG Yong-liang; SHI Hua; ZHANG Tao-lin

    2002-01-01

    A long-term experiment was conducted at the Ecological Experimental Station of Red Soil, Chinese Academy of Sciences to investigate the characteristics of material cycling and C, N accumulation in infertile red soil under different treatments of rotation systems for 11 years. Plant biomass, amount of organic materials returned to the soil, and budget of nitrogen in soil were obviously different under conventional cultivation, coverage by shrubs ( Lespedeza formosa ), rotation of shrubs ( Lespedeza formosa ) and crops (PeanutBuckwheat). Rotation of shrubs and crops with a combination of rational fertilization would be 75 - 100% of biomass and a similar amount of organic materials returned to the soil compared with that under coverage shrubs, more input than output of nitrogen, high system stability, and increasing crop productivity. With distinct cycling, different treatments of rotation systems influenced discriminatorily soil fertility. Soil organic carbon and nitrogen were respectively less than 7 and 0.6 g kg-1 for conventional cultivation, 9- 11 and 0.6-0.9 g kg-1 for rotation of shrubs and crops, 14 - 16 g kg-1 and more than 1 g kg-1 for coverage by shrubs after 11 years, which represent low, middle and high levels of upland red soil fertility at the current situation. It implied that with cultivation system and fertilization measures, the infertile red soil could have middle to high fertility after about 10 years rational utilization. Comparison of results from different treatments showed that a large loss of organic carbon and nitrogen was caused by soil erosion which resulted in a low level of C and N in upland red soil. It could be suggested that increasing carbon storage in infertile red soil would sequester a great amount of atmospheric CO2 and mitigate the global warming potentially.

  20. Sources of Nitrogen for Winter Wheat in Organic Cropping Systems

    DEFF Research Database (Denmark)

    Petersen, Søren O; Schjønning, Per; Olesen, Jørgen E;

    2013-01-01

    In organic cropping systems, legumes, cover crops (CC), residue incorporation, and manure application are used to maintain soil fertility, but the contributions of these management practices to soil nitrogen (N) supply remain obscure. We examined potential sources of N for winter wheat (Triticum...... explained 76 and 82% of the variation in grain N yields in organic cropping systems in 2007 and 2008, showing significant effects of, respectively, topsoil N, depth of A horizon, cumulated inputs of N, and N applied to winter wheat in manure. Thus, soil properties and past and current management all...... aestivum L.) in four experimental cropping systems established in 1997 on three soil types. Three of the four systems were under organic management. Topsoil N, depth of the A horizon, and cumulated inputs of N since 1997 were determined at plot level. Labile soil N pools [mineral N, potentially...

  1. Greenhouse gas emissions and global warming potential of traditional and diversified tropical rice rotation systems.

    Science.gov (United States)

    Weller, Sebastian; Janz, Baldur; Jörg, Lena; Kraus, David; Racela, Heathcliff S U; Wassmann, Reiner; Butterbach-Bahl, Klaus; Kiese, Ralf

    2016-01-01

    Global rice agriculture will be increasingly challenged by water scarcity, while at the same time changes in demand (e.g. changes in diets or increasing demand for biofuels) will feed back on agricultural practices. These factors are changing traditional cropping patterns from double-rice cropping to the introduction of upland crops in the dry season. For a comprehensive assessment of greenhouse gas (GHG) balances, we measured methane (CH4 )/nitrous oxide (N2 O) emissions and agronomic parameters over 2.5 years in double-rice cropping (R-R) and paddy rice rotations diversified with either maize (R-M) or aerobic rice (R-A) in upland cultivation. Introduction of upland crops in the dry season reduced irrigation water use and CH4 emissions by 66-81% and 95-99%, respectively. Moreover, for practices including upland crops, CH4 emissions in the subsequent wet season with paddy rice were reduced by 54-60%. Although annual N2 O emissions increased two- to threefold in the diversified systems, the strong reduction in CH4 led to a significantly lower (P < 0.05) annual GWP (CH4  + N2 O) as compared to the traditional double-rice cropping system. Measurements of soil organic carbon (SOC) contents before and 3 years after the introduction of upland crop rotations indicated a SOC loss for the R-M system, while for the other systems SOC stocks were unaffected. This trend for R-M systems needs to be followed as it has significant consequences not only for the GWP balance but also with regard to soil fertility. Economic assessment showed a similar gross profit span for R-M and R-R, while gross profits for R-A were reduced as a consequence of lower productivity. Nevertheless, regarding a future increase in water scarcity, it can be expected that mixed lowland-upland systems will expand in SE Asia as water requirements were cut by more than half in both rotation systems with upland crops.

  2. 麦稻轮作下耕作模式对土壤理化性质和作物产量的影响%Effects of tillage patterns on crop yields and soil physicochemical properties in wheat-rice rotation system

    Institute of Scientific and Technical Information of China (English)

    武际; 郭熙盛; 张祥明; 王允青; 许征宇; 鲁剑巍

    2012-01-01

    为了探明不同耕作模式对土壤理化性质和作物产量的影响,采用田间定位试验方法,于2007-2010连续4a在麦稻轮作制下开展了本试验研究.结果表明,免耕提高了耕层土壤体积质量,降低了土壤含水率.但是免耕土壤表层(0~10 cm)的体积质量仍在作物适宜生长的范围内,并未对作物的生长产生不利影响.免耕促进了土壤有机质和全氮在表层土壤的富集.0~10cm土层有机质和全氮含量比翻耕处理显著增加,而>10~20 cm土层上述养分含量明显低于翻耕处理.小麦季免耕土壤的碱解氮、速效磷和速效钾含量的变化趋势与有机质和全氮含量相似,而水稻季免耕处理整个耕层土壤碱解氮、速效磷和速效钾含量均低于翻耕处理.免耕显著的提高了小麦产量,但降低了水稻产量,起主要作用的产量构成因素是小麦和水稻的有效穗数.整个轮作周期的作物产量以小麦免耕水稻翻耕模式的产量较高,比小麦翻耕水稻免耕模式产量增加了5.70%.%In order to study effects of tillage systems on crop yields and soil physical and chemical properties in wheat-rice rotation system, a long term (2007-2010) experiment was conducted. The results showed that compared with conventional tillage, the soil bulk density increased and soil water content decreased with no-tillage. But even without tillage, bulk density of the 0-10 cm soil layer was still suitable for the growth of crops. No-tillage enriched soil organic matter and total nitrogen in the surface soil layer. Both the soil organic matter and total N content of no-tillage were significantly higher in 0-10 cm layer and lower in 10-20 cm layer than that of conventional tillage. During the wheat season, the soil alkali N, available P and available K contents had the same trends with those of organic matter and total N. Whereas during the rice season, with no-tillage, the soil alkali N、available P and available K contents

  3. A rotating inertial navigation system with the rotating axis error compensation consisting of fiber optic gyros

    Institute of Scientific and Technical Information of China (English)

    ZHA Feng; HU Bai-qing; QIN Fang-jun; LUO Yin-bo

    2012-01-01

    An effective and flexible rotation and compensation scheme is designed to improve the accuracy of rotating inertial navigation system (RINS).The accuracy of single-axial RINS is limited by the errors on the rotating axis.A novel inertial measurement unit (IMU) scheme with error compensation for the rotating axis of fiber optic gyros (FOG) RINS is presented.In the scheme,two couples of inertial sensors with similar error characteristics are mounted oppositely on the rotating axes to compensate the sensors error.Without any change for the rotation cycle,this scheme improves the system's precision and reliability,and also offers the redundancy for the system.The results of 36 h navigation simulation prove that the accuracy of the system is improved notably compared with normal strapdown INS,besides the heading accuracy is increased by 3 times compared with single-axial RINS,and the position accuracy is improved by 1 order of magnitude.

  4. Soil denitrifier community size changes with land use change to perennial bioenergy cropping systems

    Science.gov (United States)

    Thompson, Karen A.; Deen, Bill; Dunfield, Kari E.

    2016-10-01

    Dedicated biomass crops are required for future bioenergy production. However, the effects of large-scale land use change (LUC) from traditional annual crops, such as corn-soybean rotations to the perennial grasses (PGs) switchgrass and miscanthus, on soil microbial community functioning is largely unknown. Specifically, ecologically significant denitrifying communities, which regulate N2O production and consumption in soils, may respond differently to LUC due to differences in carbon (C) and nitrogen (N) inputs between crop types and management systems. Our objective was to quantify bacterial denitrifying gene abundances as influenced by corn-soybean crop production compared to PG biomass production. A field trial was established in 2008 at the Elora Research Station in Ontario, Canada (n  =  30), with miscanthus and switchgrass grown alongside corn-soybean rotations at different N rates (0 and 160 kg N ha-1) and biomass harvest dates within PG plots. Soil was collected on four dates from 2011 to 2012 and quantitative PCR was used to enumerate the total bacterial community (16S rRNA) and communities of bacterial denitrifiers by targeting nitrite reductase (nirS) and N2O reductase (nosZ) genes. Miscanthus produced significantly larger yields and supported larger nosZ denitrifying communities than corn-soybean rotations regardless of management, indicating large-scale LUC from corn-soybean to miscanthus may be suitable in variable Ontario climatic conditions and under varied management, while potentially mitigating soil N2O emissions. Harvesting switchgrass in the spring decreased yields in N-fertilized plots, but did not affect gene abundances. Standing miscanthus overwinter resulted in higher 16S rRNA and nirS gene copies than in fall-harvested crops. However, the size of the total (16S rRNA) and denitrifying bacterial communities changed differently over time and in response to LUC, indicating varying controls on these communities.

  5. Long-term rotation and tillage effects on soil structure and crop yield

    DEFF Research Database (Denmark)

    Munkholm, Lars Juhl; Heck, R; Deen, B

    2013-01-01

    long-term rotation and tillage treatment experiment on a Canadian silt loam soil. Topsoil measurements were carried out for three different rotations: R1, (C–C–C–C) continuous corn (Zea mays L.), R6, (C–C–O(RC), B(RC)) corn, corn, oats (Avena fatua L.) and spring barley (Hordeum vulgare L.) and R8, (C...

  6. Elytrigia repens population dynamics under different management schemes in organic cropping systems on coarse sand

    DEFF Research Database (Denmark)

    Rasmussen, Ilse A.; Melander, Bo; Askegaard, Margrethe;

    2014-01-01

    cereals (barley and wheat) caused the highest population increases (up to eightfold), especially when preceded by grass-clover. Winter rye and potatoes with ridging cultivations were neutral to the E. repens population. Cultivations between crops were necessary to diminish the infestation and were......-year crop rotations including various cash crops and grass-clover leys; two rotations running during the first two courses with the one replaced with another rotation during the last course. The rotations were combined with four combinations of the treatments; with and without animal manure (‘without...

  7. Multiple operating system rotation environment moving target defense

    Science.gov (United States)

    Evans, Nathaniel; Thompson, Michael

    2016-03-22

    Systems and methods for providing a multiple operating system rotation environment ("MORE") moving target defense ("MTD") computing system are described. The MORE-MTD system provides enhanced computer system security through a rotation of multiple operating systems. The MORE-MTD system increases attacker uncertainty, increases the cost of attacking the system, reduces the likelihood of an attacker locating a vulnerability, and reduces the exposure time of any located vulnerability. The MORE-MTD environment is effectuated by rotation of the operating systems at a given interval. The rotating operating systems create a consistently changing attack surface for remote attackers.

  8. SMALLHOLDER FARMERS’ WILLINGNESS TO INCORPORATE BIOFUEL CROPS INTO CROPPING SYSTEMS IN MALAWI

    Directory of Open Access Journals (Sweden)

    Beston Bille Maonga

    2015-01-01

    Full Text Available Using cross-sectional data, this study analysed the critical and significant socioeconomic factors with high likelihood to determine smallholder farmers’ decision and willingness to adopt jatropha into cropping systems in Malawi. Employing desk study and multi-stage random sampling technique a sample of 592 households was drawn from across the country for analysis. A probit model was used for the analysis of determinants of jatropha adoption by smallholder farmers. Empirical findings show that education, access to loan, bicycle ownership and farmers’ expectation of raising socioeconomic status are major significant factors that would positively determine probability of smallholder farmers’ willingness to adopt jatropha as a biofuel crop on the farm. Furthermore, keeping of ruminant herds of livestock, long distance to market and fears of market unavailability have been revealed to have significant negative influence on farmers’ decision and willingness to adopt jatropha. Policy implications for sustainable crop diversification drive are drawn and discussed.

  9. Experiences and Research Perspectives on Sustainable Development of Rice-Wheat Cropping Systems in the Chengdu Plain,China

    Institute of Scientific and Technical Information of China (English)

    ZHENG Jia-guo; CHI Zhong-zhi; JIANG Xin-lu; TANG Yong-lu; ZHANG Hong

    2010-01-01

    The rice and wheat cropping pattern is one of the main cropping systems in the world.A large number of research results showed that successive cropping of rice and wheat resulted in a series of problems such as hindering nutrition absorption,gradual degeneration of soil fertility,decline of soil organic matter,and increased incidence of diseases and pests.In China,especially in the Chengdu plain where rice-wheat cropping system is practiced,productivity and soil fertility was enhanced and sustained.This paper reviews the relevant data and experiences on rice-wheat cropping in the Chengdu Plain from 1977 to 2006.The principal sustainable strategies used for rice-wheat cropping systems in Chengdu Plain included: 1)creating a favorable environment and viable rotations; 2)balanced fertilization for maintenance of sustainable soil productivity; 3)improvement of crop management for higher efficiency; and 4)use the newest cultivars and cultivation techniques to upgrade the production level.Future research is also discussed in the paper as: 1)the constant topic: a highly productive and efficient rice-wheat cropping system for sustainable growth; 2)the future trend: simplified cultivation techniques for the rice-wheat cropping system; 3)the foundation: basic research for continuous innovation needed for intensive cropping.It is concluded that in the rice-wheat cropping system,a scientific and reasonable tillage/cultivation method can not only avoid the degradation of soil productivity,but also maintain sustainable growth in the long run.

  10. 麦稻轮作区周年耕作模式对作物产量和土壤特性的影响%Effect of Different Annual Tillage Patterns on Crop Yield and Soil Properties in Wheat-rice Rotation System

    Institute of Scientific and Technical Information of China (English)

    李朝苏; 汤永禄; 黄钢; 吴春; 马孝玲

    2012-01-01

    2004~2009年,在成都平原麦稻轮作区研究了不同周年耕作模武(周年翻耕无秸秆还田、小麦免耕稻草覆盖还田+水稻旋耕无秸秆还田、麦稻周年免耕秸秆全量还田、麦稻周年垄作免耕秸秆全量还田)对作物产量和土壤特性的影响.结果表明,不同模式闻小麦产量差异较小,水稻产量差异较大;免旋结合稻草覆盖还田模式年际间水稻产量较其他模式稳定.麦稻关健生育阶段0~30cm土层速效养分含量模式间差异较小;免旋结合稻草覆盖利于土壤表层有机质积累.周年免耕秸秆全量还田模武20cm处紧实度降低,渗水速率增大,保水性能下降.研究结果说明,不同耕作模式下土壤养分供给能力不是影响作物产量的主要因素,因土壤物理性质变化导致水分下渗差异是水稻产量差异的重要原因,免旋结合稻草覆盖还田模式似乎更利于麦稻轮作田生产能力的稳定.%The wheat-rice rotation system was the major cropping system in south Asia and the Yangtze River Basin of China. From 2004 to 2009, the effect of different annual tillage patterns on crop yields and soil properties in a wheat-rice rotation system was studied in the Chengdu Plain. The effects of four tillage patterns (annual plowing, no-tillage in wheat season with rice straw returning and rotary tillage in rice season, annual no-tillage with rice and wheat straw returning, annual ridge-no-tillage with rice and wheat straw retuming)were tested in the experiment. The results showed that the difference in wheat yield among different treatments in the same year was not significant, but the difference in rice yield was obvious. The rice yield of the treatments with annual no-tillage and total straw mulching was lower than that of the control treatment with annual plowing and no straw returning, and decreased over the years. The rice yield of the treatments with no tillage in the wheat season and rice straw returning and

  11. Implementation of dynamic crop growth processes into a land surface model: evaluation of energy, water and carbon fluxes under corn and soybean rotation

    Directory of Open Access Journals (Sweden)

    Y. Song

    2013-06-01

    Full Text Available Worldwide expansion of agriculture is impacting Earth's climate by altering the carbon, water and energy fluxes, but climate in turn is impacting crop production. To study this two-way interaction and its impact on seasonal dynamics of carbon, water and energy fluxes, we implemented dynamic crop growth processes into a land surface model, the Integrated Science Assessment Model (ISAM. In particular, we implement crop specific phenology schemes, which account for light, water, and nutrient stresses while allocating the assimilated carbon to leaf, root, stem and grain pools; dynamic vegetation structure growth, which better simulate the LAI and canopy height; dynamic root distribution processes in the soil layers, which better simulate the root response of soil water uptake and transpiration; and litter fall due to fresh and old dead leaves to better represent the water and energy interception by both stem and brown leaves of the canopy during leaf senescence. Observational data for LAI, above and below ground biomass, and carbon, water and energy fluxes were compiled from two Ameri-Flux sites, Mead, NE and Bondville, IL, to calibrate and evaluate the model performance under corn (C4-soybean (C3 rotation system over the period 2001–2004. The calibrated model was able to capture the diurnal and seasonal patterns of carbon assimilation, water and energy fluxes under the corn-soybean rotation system at these two sites. Specifically, the calculated GPP, net radiation fluxes at the top of canopy and latent heat fluxes compared well with observations. The largest bias in model results is in sensible heat flux (H for corn and soybean at both sites. With dynamic carbon allocation and root distribution processes, model simulated GPP and latent heat flux (LH were in much better agreement with observation data than for the without dynamic case. Modeled latent heat improved by 12–27% during the growing season at both sites, leading to the improvement in

  12. Counter-Rotating Tandem Motor Drilling System

    Energy Technology Data Exchange (ETDEWEB)

    Kent Perry

    2009-04-30

    Gas Technology Institute (GTI), in partnership with Dennis Tool Company (DTC), has worked to develop an advanced drill bit system to be used with microhole drilling assemblies. One of the main objectives of this project was to utilize new and existing coiled tubing and slimhole drilling technologies to develop Microhole Technology (MHT) so as to make significant reductions in the cost of E&P down to 5000 feet in wellbores as small as 3.5 inches in diameter. This new technology was developed to work toward the DOE's goal of enabling domestic shallow oil and gas wells to be drilled inexpensively compared to wells drilled utilizing conventional drilling practices. Overall drilling costs can be lowered by drilling a well as quickly as possible. For this reason, a high drilling rate of penetration is always desired. In general, high drilling rates of penetration (ROP) can be achieved by increasing the weight on bit and increasing the rotary speed of the bit. As the weight on bit is increased, the cutting inserts penetrate deeper into the rock, resulting in a deeper depth of cut. As the depth of cut increases, the amount of torque required to turn the bit also increases. The Counter-Rotating Tandem Motor Drilling System (CRTMDS) was planned to achieve high rate of penetration (ROP) resulting in the reduction of the drilling cost. The system includes two counter-rotating cutter systems to reduce or eliminate the reactive torque the drillpipe or coiled tubing must resist. This would allow the application of maximum weight-on-bit and rotational velocities that a coiled tubing drilling unit is capable of delivering. Several variations of the CRTDMS were designed, manufactured and tested. The original tests failed leading to design modifications. Two versions of the modified system were tested and showed that the concept is both positive and practical; however, the tests showed that for the system to be robust and durable, borehole diameter should be substantially larger

  13. Robust cropping systems to tackle pests under climate change

    DEFF Research Database (Denmark)

    Lamichhane, Jay Ram; Barzman, Marco; Booij, Kees

    2015-01-01

    approaches involving extension and other stakeholders will help meet the challenge of developing more robust cropping systems; (5) farmers can take advantage of Web 2.0 and other new technologies to make the exchange of updated information quicker and easier; (6) cooperation between historically...... compartmentalized experts in plant health and crop protection could help develop anticipation strategies; and (7) the current decline in skilled crop protection specialists in Europe should be reversed, and shortcomings in local human and financial resources can be overcome by pooling resources across borders......., cropping systems, and pests; (2) the unpredictable adaptation of pests to a changing environment primarily creates uncertainty and projected changes do not automatically translate into doom and gloom scenarios; (3) faced with uncertainty, policy, research, and extension should prepare for worst...

  14. Relation between N fertilization and N{sub 2}O release in different crop rotations

    Energy Technology Data Exchange (ETDEWEB)

    Stoeven, K.; Kohrs, K.; Schnug, E. [Federal Research Central Agency, Braunschweig (Germany)

    2002-07-01

    The influence of N-fertilization and crop species on the release of the greenhouse gas N{sub 2}O was investigated at two sites in northern Germany from June 1994 till October 1996. The N{sub 2}O release was measured daily. The results were correlated to the nitrate and ammonia content of the soil as well as to fertilizer type, crop species and soil moisture. The results of the investigations showed no effect of N-fertilizer type or crop species on the N{sub 2}O release. Main result of this work is that lowering the N fertilization to about 50% of the standard could reduce the N{sub 2}O release.

  15. The value of crop germplasm and value accounting system

    Institute of Scientific and Technical Information of China (English)

    WANG Xiaowei; DING Guangzhou; CHANG Ying

    2007-01-01

    The value evaluation and accounting of crop germplasm not only provides the theory and method for the price of germplasm, thus makes further lawful and fair transactions, but also ensures the benefits of crop germplasm owners and is also instructive in keeping the foodstuff safety. This paper founded a multidimensional value accounting system, which included physical accounting, value accounting and quality index accounting; individual accounting and total accounting; quantity accounting and quality accounting.

  16. Effects of different potato cropping system approaches and water management on soilborne diseases and soil microbial communities.

    Science.gov (United States)

    Larkin, Robert P; Honeycutt, C Wayne; Griffin, Timothy S; Olanya, O Modesto; Halloran, John M; He, Zhongqi

    2011-01-01

    Four different potato cropping systems, designed to address specific management goals of soil conservation, soil improvement, disease suppression, and a status quo standard rotation control, were evaluated for their effects on soilborne diseases of potato and soil microbial community characteristics. The status quo system (SQ) consisted of barley underseeded with red clover followed by potato (2-year). The soil-conserving system (SC) featured an additional year of forage grass and reduced tillage (3-year, barley/timothy-timothy-potato). The soil-improving system (SI) added yearly compost amendments to the SC rotation, and the disease-suppressive system (DS) featured diverse crops with known disease-suppressive capability (3-year, mustard/rapeseed-sudangrass/rye-potato). Each system was also compared with a continuous potato control (PP) and evaluated under both irrigated and nonirrigated conditions. Data collected over three potato seasons following full rotation cycles demonstrated that all rotations reduced stem canker (10 to 50%) relative to PP. The SQ, SC, and DS systems reduced black scurf (18 to 58%) relative to PP; SI reduced scurf under nonirrigated but not irrigated conditions; and scurf was lower in DS than all other systems. The SQ, SC, and DS systems also reduced common scab (15 to 45%), and scab was lower in DS than all other systems. Irrigation increased black scurf and common scab but also resulted in higher yields for most rotations. SI produced the highest yields under nonirrigated conditions, and DS produced high yields and low disease under both irrigation regimes. Each cropping system resulted in distinctive changes in soil microbial community characteristics as represented by microbial populations, substrate utilization, and fatty acid methyl-ester (FAME) profiles. SI tended to increase soil moisture, microbial populations, and activity, as well result in higher proportions of monounsaturated FAMEs and the FAME biomarker for mycorrhizae (16:1

  17. Senior Research Connects Students with a Living Laboratory As Part of an Integrated Crop and Livestock System

    Science.gov (United States)

    Senturklu, Songul; Landblom, Douglas; Brevik, Eric C.

    2015-04-01

    Soil, water, soil microbes, and solar energy are the main sources that sustain life on this planet. Without them working in concert, neither plants nor animals would survive. Considering the efficiency of animal production targets, soil must be protected and improved. Therefore, through our sustainable integrated crop and livestock research, we are studying animal and soil interactions from the soil to the plate. Integrating beef cattle systems into a diverse cropping system is providing a living laboratory for education beyond the traditional classroom setting. To establish the living learning laboratory at the Dickinson Research Extension Center, a five-crop rotation was established that included adapted cool and warm season grasses and broadleaf crops. The crop rotation is: sunflower > hard red spring wheat > fall seeded winter triticale-hairy vetch (hay)/spring seeded 7-species cover crop > Corn (85-95 day varieties) > field pea-barley intercrop. Sunflower and spring wheat are harvested for cash crop income in the rotation. Livestock integration occurs when yearling steers that had previously grazed perennial pastures until mid-August graze field pea-barley and subsequently unharvested corn. Average grazing days for field pea-barley and unharvested corn is 30 and 70 days, respectively. At the end of the grazing period, the yearling steers average 499-544 kg and are moved to a feedlot and fed an additional 75 days until slaughter. Maximizing grazing days and extending the grazing season through integration with the cropping system reduces custom feeding costs and enhances animal profit. Beef cows do not require high quality feed after their calves have been weaned. Therefore, gestating beef cows are an ideal animal to graze cover crops and crop aftermath (residue) after yearling steer grazing and farming operations have been completed. Extending the grazing season for beef cows by grazing cover crops and residues reduces winter feed cost, which is one of the

  18. Regional modelling of nitrate leaching from Swiss organic and conventional cropping systems under climate change

    Science.gov (United States)

    Calitri, Francesca; Necpalova, Magdalena; Lee, Juhwan; Zaccone, Claudio; Spiess, Ernst; Herrera, Juan; Six, Johan

    2016-04-01

    predictions for conventional cropping system with a three years rotation (silage maize, potatoes and winter wheat) in Zurich and Bern cantons varied from 6.30 to 16.89 g N m-2 y-1 over a 30-years period. Further simulations and analyses will follow to provide insights into understanding of driving variables and patterns of N losses by leaching in response to changes from conventional to organic cropping systems, and climate change.

  19. Residue management increases fallow water conservation and yield deficit irrigated crops grown in rotation with wheat

    Science.gov (United States)

    No-tillage (NT) residue management provides cover to increase precipitation capture compared with disk tillage (DT) or in the absence of a cover crop. Therefore, NT has the potential to reduce irrigation withdrawals from the declining Ogallala Aquifer. In a 4-year study, we quantified DT and NT effe...

  20. Residual soil nitrate content and profitability of five cropping systems in northwest Iowa

    Science.gov (United States)

    Schuiteman, Matthew A.; Vos, Ronald J.

    2017-01-01

    Many communities in the Midwestern United States obtain their drinking water from shallow alluvial wells that are vulnerable to contamination by NO3-N from the surrounding agricultural landscape. The objective of this research was to assess cropping systems with the potential to produce a reasonable return for farmers while simultaneously reducing the risk of NO3-N movement into these shallow aquifers. From 2009 to 2013 we conducted a field experiment in northwest Iowa in which we evaluated five cropping systems for residual (late fall) soil NO3-N content and profitability. Soil samples were taken annually from the top 30 cm of the soil profile in June and August, and from the top 180 cm in November (late fall). The November samples were divided into 30 cm increments for analysis. Average residual NO3-N content in the top 180 cm of the soil profile following the 2010 to 2013 cropping years was 134 kg ha-1 for continuous maize (Zea mays L.) with a cereal rye (Secale cereale L.) cover crop, 18 kg ha-1 for perennial grass, 60 kg ha-1 for a three year oat (Avena sativa L.)-alfalfa (Medicago sativa L.)-maize rotation, 85 kg ha-1 for a two year oat/red clover (Trifolium pratense L.)-maize rotation, and 90 kg ha-1 for a three year soybean (Glycine max (L.) Merr.)-winter wheat (Triticum aestivum L.)-maize rotation. However, residual NO3-N in the 90 to 180 cm increment of the soil profile was not significantly higher in the oat-alfalfa-maize cropping system than the perennial grass system. For 2010 to 2013, average profit ($ ha-1 yr-1) was 531 for continuous corn, 347 for soybean-winter wheat-maize, 264 for oat-alfalfa-maize, 140 for oat/red clover-maize, and -384 (loss) for perennial grass. Considering both residual soil NO3-N and profitability data, the oat-alfalfa-maize rotation performed the best in this setting. However, given current economic pressures widespread adoption is likely to require changes in public policy. PMID:28248976

  1. Nuances and nuisances : crop production intensification options for smallholder farming systems of southern Africa

    NARCIS (Netherlands)

    Rusinamhodzi, L.

    2013-01-01

    Key words: crop production, intensification, extensification, farming systems, tradeoff analysis, maize, legume, manure, fertiliser, southern Africa Soil fertility decline and erratic rainfall are major constraints to crop productivity on smallholder farms in southern Africa. Crop

  2. A STELLA Model to Estimate Water and Nitrogen Dynamics in a Short-Rotation Woody Crop Plantation.

    Science.gov (United States)

    Ouyang, Ying; Zhang, Jiaen; Leininger, Theodor D; Frey, Brent R

    2015-01-01

    Although short-rotation woody crop biomass production technology has demonstrated a promising potential to supply feedstocks for bioenergy production, the water and nutrient processes in the woody crop planation ecosystem are poorly understood. In this study, a computer model was developed to estimate the dynamics of water and nitrogen (N) species (e.g., NH-N, NO-N, particulate organic N, and soluble organic N [SON]) in a woody crop plantation using STELLA (tructural hinking and xperiential earning aboratory with nimation) software. A scenario was performed to estimate diurnal and monthly water and N variations of a 1-ha mature cottonwood plantation over a 1-yr simulation period. A typical monthly variation pattern was found for soil water evaporation, leaf water transpiration, and root water uptake, with an increase from winter to summer and a decrease from summer to the following winter. Simulations further revealed that the rate of soil water evaporation was one order of magnitude lower than that of leaf water transpiration. In most cases, the relative monthly water loss rates could be expressed as evapotranspiration > root uptake > percolation > runoff. Leaching of NO-N and SON depended not only on soil N content but also on rainfall rate and duration. Leaching of NO-N from the cottonwood plantation was about two times higher than that of SON. The relative monthly rate of N leaching was NO-N > SON > NH-N. This study suggests that the STELLA model developed is a useful tool for estimating water and N dynamics from a woody crop plantation.

  3. 缓释氮肥运筹对稻麦轮作周年作物产量和氮肥利用率的影响%Effects of slow-released nitrogen fertilizers with different application patterns on crop yields and nitrogen fertilizer use efficiency in rice-wheat rotation system

    Institute of Scientific and Technical Information of China (English)

    许仙菊; 马洪波; 宁运旺; 汪吉东; 张永春

    2016-01-01

    量具有较好的稳定效果,但是个别缓释氮肥减施对水稻有减产风险,有必要依据稻田土壤氮素转化特点,研制水稻专用缓释氮肥,适当降低水稻季缓释氮肥的施用量。%[Objectives]Rice-wheat rotation is one of the most important agricultural cultivation systems in China where large amounts of fertilizer are applied.Yield increases of rice and wheat, decrease of fertilizer application amount, and increase of fertilizer use efficiency can benefit from research on application patterns and methods of various fertilizers in such rice-wheat rotation regions.Slow-released fertilizers as nutrient-efficient and environment-friendly fertilizers have been extensively reported to function in increasing yields and fertilizer use efficiencies in various crop species.However, less attention is paid to effects of slow-released fertilizers in crop rotation system, especially rice-wheat rotation system which is the most important rotation system in southern China.[Methods]Here, the effects of different slow-released fertilizers on the yields of rice and wheat, the use efficiency of nitrogen fertilizer, the contents of soil nutrients, and the soil nitrogen balance were studied through a two-year field plot experiment of the rice-wheat rotation.There were six experimental treatments including no nitrogen, custom fertilizer, slow-release fertilizer Ⅰ ( 20% common urea +80% sulfur coated urea ) , slow-release fertilizer Ⅱ(20%common urea +80%polymer coated urea) , slow-release fertilizerⅢ( common urea +0.8%NAM) and slow-release fertilizerⅣ (common urea +0.8% NAM).Among them, the nitrogen application amounts of the slow-release fertilizerⅠ, slow-release fertilizerⅡand slow-release fertilizerⅢwere reduced by 24.3%, and the nitrogen application amount of slow-release fertilizer Ⅳwas reduced by 10.8%.[Results]Compared with the no nitrogen application, all treatments with the nitrogen application increase the yields of wheat

  4. Black locust (Robinia pseudoacacia L. Short-Rotation Crops under Marginal Site Conditions

    Directory of Open Access Journals (Sweden)

    RÉDEI, Károly

    2011-01-01

    Full Text Available The improvement of the reliability of renewable resources and the decline in reserves offossile raw material in the coming decades will lead to increasing demands for wood material andconsequently to a greater role of short rotation forestry (SRF. Particular efforts have been made inEurope to substitute fossils with renewables, in this context the proportion of renewable energy shouldbe increased to 20% by 2020. SRF can be provide relatively high dendromass (biomass incrementrates if the short rotation tree plantations are grown under favourable site conditions and for anoptimum rotation length. However, in many countries only so-called marginal sites are available forsetting up tree plantations for energy purpose. For SRF under marginal site conditions black locust(Robinia pseudoacacia L. can be considered as one of the most promising tree species thanks to itsfavourable growing characteristics. According to a case study presented in the paper black locust canproduce a Mean Annual Increment (MAI of 2.9 to 9.7 oven-dry tons ha–1 yr–1 at ages between 3 and7 years using a stocking density of 6667 stems ha–1. On the base of the presented results and accordingto international literature the expected dendromass volume shows great variation, depending upon site,species, their cultivars, initial spacing and length of rotation cycle.

  5. Cyclic integrals and reduction of rotational relativistic Birkhoffian system

    Institute of Scientific and Technical Information of China (English)

    罗绍凯

    2003-01-01

    The order reduction method of the rotational relativistic Birkhoffian equations is studied. For a rotational relativistic Birkhoffian system, the cyclic integrals can be found by using the perfect differential method. Through these cyclic integrals, the order of the system can be reduced. If the rotational relativistic Birkhoffian system has a cyclic integral, then the Birkhoffian equations can be reduced at least two degrees and the Birkhoffian form can be kept. An example is given to illustrate the application of the results.

  6. The Importance of Rotational Crops for Biodiversity Conservation in Mediterranean Areas.

    Science.gov (United States)

    Chiatante, Gianpasquale; Meriggi, Alberto

    2016-01-01

    Nowadays we are seeing the largest biodiversity loss since the extinction of the dinosaurs. To conserve biodiversity it is essential to plan protected areas using a prioritization approach, which takes into account the current biodiversity value of the sites. Considering that in the Mediterranean Basin the agro-ecosystems are one of the most important parts of the landscape, the conservation of crops is essential to biodiversity conservation. In the framework of agro-ecosystem conservation, farmland birds play an important role because of their representativeness, and because of their steady decline in the last Century in Western Europe. The main aim of this research was to define if crop dominated landscapes could be useful for biodiversity conservation in a Mediterranean area in which the landscape was modified by humans in the last thousand years and was affected by the important biogeographical phenomenon of peninsula effect. To assess this, we identify the hotspots and the coldspots of bird diversity in southern Italy both during the winter and in the breeding season. In particular we used a scoring method, defining a biodiversity value for each cell of a 1-km grid superimposed on the study area, using data collected by fieldwork following a stratified random sampling design. This value was analysed by a multiple linear regression analysis and was predicted in the whole study area. Then we defined the hotspots and the coldspots of the study area as 15% of the cells with higher and lower value of biodiversity, respectively. Finally, we used GAP analysis to compare hotspot distribution with the current network of protected areas. This study showed that the winter hotspots of bird diversity were associated with marshes and water bodies, shrublands, and irrigated crops, whilst the breeding hotspots were associated with more natural areas (e.g. transitional wood/shrubs), such as open areas (natural grasslands, pastures and not irrigated crops). Moreover, the

  7. Implementation of dynamic crop growth processes into a land surface model: evaluation of energy, water and carbon fluxes under corn and soybean rotation

    Science.gov (United States)

    Song, Y.; Jain, A. K.; McIsaac, G. F.

    2013-12-01

    Worldwide expansion of agriculture is impacting the earth's climate by altering carbon, water, and energy fluxes, but the climate in turn is impacting crop production. To study this two-way interaction and its impact on seasonal dynamics of carbon, water, and energy fluxes, we implemented dynamic crop growth processes into a land surface model, the Integrated Science Assessment Model (ISAM). In particular, we implemented crop-specific phenology schemes and dynamic carbon allocation schemes. These schemes account for light, water, and nutrient stresses while allocating the assimilated carbon to leaf, root, stem, and grain pools. The dynamic vegetation structure simulation better captured the seasonal variability in leaf area index (LAI), canopy height, and root depth. We further implemented dynamic root distribution processes in soil layers, which better simulated the root response of soil water uptake and transpiration. Observational data for LAI, above- and belowground biomass, and carbon, water, and energy fluxes were compiled from two AmeriFlux sites, Mead, NE, and Bondville, IL, USA, to calibrate and evaluate the model performance. For the purposes of calibration and evaluation, we use a corn-soybean (C4-C3) rotation system over the period 2001-2004. The calibrated model was able to capture the diurnal and seasonal patterns of carbon assimilation and water and energy fluxes for the corn-soybean rotation system at these two sites. Specifically, the calculated gross primary production (GPP), net radiation fluxes at the top of the canopy, and latent heat fluxes compared well with observations. The largest bias in model results was in sensible heat flux (SH) for corn and soybean at both sites. The dynamic crop growth simulation better captured the seasonal variability in carbon and energy fluxes relative to the static simulation implemented in the original version of ISAM. Especially, with dynamic carbon allocation and root distribution processes, the model

  8. Crop protection in European maize-based cropping systems: Current practices and recommendations for innovative Integrated Pest Management

    NARCIS (Netherlands)

    Vasileiadisa, V.P.; Sattin, M.; Weide, van der R.Y.

    2011-01-01

    Maize-based cropping systems (MBCSs), with different frequency of maize in the crop sequence, are common in European arable systems. Pesticide use differs according to the type of active ingredients and target organisms in different regions. Within the EU Network of Excellence ENDURE, two expert-bas

  9. Reducing soil erosion and nutrient loss on sloping land under crop-mulberry management system.

    Science.gov (United States)

    Fan, Fangling; Xie, Deti; Wei, Chaofu; Ni, Jiupai; Yang, John; Tang, Zhenya; Zhou, Chuan

    2015-09-01

    Sloping croplands could result in soil erosion, which leads to non-point source pollution of the aquatic system in the Three Gorges Reservoir Region. Mulberry, a commonly grown cash plant in the region, is traditionally planted in contour hedgerows as an effective management practice to control soil erosion and non-point source pollution. In this field study, surface runoff and soil N and P loss on sloping land under crop-mulberry management were investigated. The experiments consisted of six crop-mulberry treatments: Control (no mulberry hedgerow with mustard-corn rotation); T1 (two-row contour mulberry with mustard-corn rotation); T2 (three-row contour mulberry with mustard-corn rotation); T3 (border mulberry and one-row contour mulberry with mustard-corn rotation); T4 (border mulberry with mustard-corn rotation); T5 (two-row longitudinal mulberry with mustard). The results indicated that crop-mulberry systems could effectively reduce surface runoff and soil and nutrient loss from arable slope land. Surface runoff from T1 (342.13 m(3) hm(-2)), T2 (260.6 m(3) hm(-2)), T3 (113.13 m(3) hm(-2)), T4 (114 m(3) hm(-2)), and T5 (129 m(3) hm(-2)) was reduced by 15.4, 35.6, 72.0, 71.8, and 68.1%, respectively, while soil loss from T1 (0.21 t hm(-2)), T2 (0.13 t hm(-2)), T3 (0.08 t hm(-2)), T4 (0.11 t hm(-2)), and T5 (0.12 t hm(-2)) was reduced by 52.3, 70.5, 81.8, 75.0, and 72.7%, respectively, as compared with the control. Crop-mulberry ecosystem would also elevate soil N by 22.3% and soil P by 57.4%, and soil nutrient status was contour-line dependent.

  10. Short Rotation Woody Crops Program. Quarterly progress report, March 1-May 31, 1985. [Sycamore, alders, black locust, larch, poplars, saltbush

    Energy Technology Data Exchange (ETDEWEB)

    Wright, L.L.; Perlack, R.D.; Wenzel, C.R.; Trimble, J.L.; Ranney, J.W.

    1985-08-01

    This report covers the progress of the Short Rotation Woody Crops Program (SRWCP) during the third quarter of fiscal year 1985. This report summarizes ORNL management activities, technical activities at ORNL and subcontract institutions, and the technology transfer that is occurring as a result of subcontractor and ORNL activities. Third-year results of a nutrient utilization study confirmed that there were no benefits to quarterly fertilization with urea nitrogen. Testing of one prototype short-rotation intensive culture harvester was conducted on a sycamore plantation on Scott Paper Company land in southern Alabama. Coppice yields of European black alder reported by Iowa State University indicate potential productivity of about 7.2 dry Mg . ha/sup -1/ . year/sup -1/ if the best trees are selected. Coppice yields were more than double first-rotation yields. About 31,000 black locust and larch trees were established in 12 genetic tests at 4 sites in Michigan. Seedling rotation productivity rates of 4-year-old hybrid poplar, based on harvest data, were reported by Pennsylvania State University. Rates varied from 4.8 dry Mg . ha/sup -1/ . year/sup -1/ to 10.7 dry Mg . ha/sup -1/ . year/sup -1/, depending on site, management strategy, and planting year. An efficient method for in vitro micropropagation of elite genotypes of fourwing saltbush was developed by Plant Resources Institute. A new study to evaluate yield/density relationships was established by the USDA Forest Service, Pacific Northwest Forest and Range Experiment Station. Dissertation research on the crown geometry of plantation-grown American sycamore was completed.

  11. Residual Influence of Early Season Crop Fertilization and Cropping System on Growth and Yield of Cassava

    Directory of Open Access Journals (Sweden)

    E. A. Makinde

    2008-01-01

    Full Text Available Problem statement: In assessing fertilizer effects to sustain an intensive cropping system, the residual effects of fertilizer applied to preceding maize on the growth and yield of cassava and the effects of intercropping with soybean were studied in field experiments at Ibadan, Nigeria. Approach: Maize, established in April was fertilized using either organic manure or inorganic fertilizer or a mixture of organic manure and inorganic fertilizers. Organic manure was an equal mixture of domestic waste collected from a composted refuse dumping site applied at l0 t ha-1. Inorganic fertilizer was 150kg N supplied as urea and 50 kg P ha-1 as Single Super phosphate fertilizer. The mixture of organic and inorganic fertilizer treatment was 5 tonnes organic manure and 75kg N+25 kg P ha-1. Cassava was established in June and soybean planted in July, after harvesting maize. Results: Organic fertilizer treatment gave the tallest plants of 53 cm. Plants from sole inorganic fertilizer and from a mixture of organic and inorganic fertilizers had comparable heights but were significantly lower than plants from sole organic fertilizer application. Organic fertilizer application gave the highest seed yield of 481 kg ha-1 that was significantly higher than 380 kg ha-1 observed from a mixture of organic and inorganic fertilizers. Stover yield followed the same trend as seed yield. Cassava plant height was increased with fertilization but was reduced with intercropping. Sole organic fertilization had the tallest plants. Plant leaf area was neither significantly affected by fertilizer type nor cropping system. Fresh root yield was significantly reduced by 16% with soybean intercropping. Sole organic fertilizer application gave the highest yields of 22 tons ha-1 in sole crop and 18 tons ha-1 in intercrop with soybean. Conclusion: Cultivating an early season maize crop, followed by a cassava-soybean intercrop is more

  12. Noether's theorem of a rotational relativistic variable mass system

    Institute of Scientific and Technical Information of China (English)

    方建会; 赵嵩卿

    2002-01-01

    Noether's theory of a rotational relativistic variable mass system is studied. Firstly, Jourdain's principle of therotational relativistic variable mass system is given. Secondly, on the basis of the invariance of the Jourdain's principleunder the infinitesimal transformations of groups, Noether's theorem and its inverse theorem of the rotational relativisticvariable mass system are presented. Finally, an example is given to illustrate the application of the result.

  13. Policies for Reintegrating Crop and Livestock Systems: A Comparative Analysis

    Directory of Open Access Journals (Sweden)

    Rachael D. Garrett

    2017-03-01

    Full Text Available The reintegration of crop and livestock systems within the same land area has the potential to improve soil quality and reduce water and air pollution, while maintaining high yields and reducing risk. In this study, we characterize the degree to which federal policies in three major global food production regions that span a range of socioeconomic contexts, Brazil, New Zealand, and the United States, incentivize or disincentivize the use of integrated crop and livestock practices (ICLS. Our analysis indicates that Brazil and New Zealand have the most favorable policy environment for ICLS, while the United States provides the least favorable environment. The balance of policy incentives and disincentives across our three cases studies mirrors current patterns of ICLS usage. Brazil and New Zealand have both undergone a trend toward mixed crop livestock systems in recent years, while the United States has transitioned rapidly toward continuous crop and livestock production. If transitions to ICLS are desired, particularly in the United States, it will be necessary to change agricultural, trade, environmental, biofuels, and food safety policies that currently buffer farmers from risk, provide too few incentives for pollution reduction, and restrict the presence of animals in crop areas. It will also be necessary to invest more in research and development in all countries to identify the most profitable ICLS technologies in each region.

  14. Comprehensive evaluation of multiple cropping systems on upland red soil

    Institute of Scientific and Technical Information of China (English)

    Guoqin HUANG; Xiuying LIU; Longwang LIU; Fang YE; Mingling ZHANG; Yanhong SHU

    2008-01-01

    According to the principles and methods of ecology and system engineering,we set up an evaluation indicator system for multi-component and multiple crop-ping systems,evaluated the comprehensive benefits of multi-component and multiple cropping systems using grey relation clustering analysis and screened out the opti-mized model based on research done in the upland red soil in Jiangxi Agricultural University from 1984 to 2004.The results show that the grey relation degree of "cabbage/ potato/maize-sesame" was the highest among 23 multi-component and multiple cropping systems and was clustered into the optimized system.This indicates that "cabbage/potato/maize - sesame" can bring the best social,economic and ecological benefits,increase product yield and farmers' income and promote sustainable development of agricultural production.Therefore,it is suitable for promotion on upland red soil.The grey rela-tion degree of "canola/Chinese milk vetch/maize/mung bean/maize" was second,which is suitable for imple-mentation at the city outskirts.In conclusion,these two planting patterns are expected to play important roles in the reconstruction of the planting structure and optimiza-tion of the planting patterns on upland red soil.

  15. Crop rotation and seasonal effects on fatty acid profiles of neutral and phospholipids extracted from no-till agricultural soils

    DEFF Research Database (Denmark)

    Ferrari, Alejandro E.; Ravnskov, Sabine; Larsen, John

    2015-01-01

    to winter differentially according to soil treatment being the smallest decrease inHR management 35%. Both PLFA and NLFA profiles showed strong potential to discriminatebetween different land uses. In winter samples, some rare or unknown fatty acids were relevant forthe discrimination of agricultural...... practices while NLFA 20:0 appears to be a good marker of HRsoils despite season or location. The PLFA-based taxonomic biomarkers for total bacteria, Gramnegativebacteria and arbuscular mycorrhiza showed a significant trend NE>HR>LR in the wintersampling. HR management was also characterized by high levels...... of NLFA in winter samples as ifhigh crop rotation improves lipids reserves in soil during winter more than in monocropping soilmanagement. In conclusion, PLFA and particularly NLFA profiles appear to provide useful andcomplementary information to obtain a footprint of different soil use and managements...

  16. EVOLUTIONS OF A BLACK-GRASS POPULATION SUBMITTED TO DIVERSE CROP SYSTEMS.

    Science.gov (United States)

    Henriet, F; Matrheeuws, L; Verbiest, M

    2014-01-01

    Black-grass is a common grass weed, widely spread in Northern Europe and also in Belgium. The first case of resistance in Belgium was reported by Eelen et al. (1996). Since then, monitoring showed that resistant black-grass was not confined to restricted areas anymore and that all usually effective modes of action could be subject to resistance issue (Henriet and Maréchal, 2009). There is no report that agrochemical companies will soon bring a new mode of action effective against grasses on the market, in a close future. It is therefore important to preserve the still effective actives by integrating them into global weeding strategies. A long-lasting trial was set up in order to study the evolution of a black-grass population when submitted to diverse crop systems. Several factors were studied such as rotation (quadri-annual-bisannual-monoculture winter wheat), sowing date (standard date or delayed), cultivation (inversion tillage or not) and herbicide treatments. During three years, each time winter wheat occurred in the rotation, each plot gets the same factorial combination (rotation excepted). In untreated plots, black-grass head counting's showed no differences between tillage or not and bisannual or quadri-annual rotation. On the other hand, number of black-grass heads was higher in standard sowing date and monoculture than in delayed sowing date and other rotations, respectively. The general efficacy of the herbicide treatments was decreasing over the years.

  17. The perspective crops for the bioregenerative human life support systems

    Science.gov (United States)

    Polonskiy, Vadim; Polonskaya, Janna

    The perspective crops for the bioregenerative human life support systems V.I. Polonskiy, J.E. Polonskaya aKrasnoyarsk State Agrarian University, 660049, Krasnoyarsk, Russia In the nearest future the space missions will be too long. In this case it is necessary to provide the crew by vitamins, antioxidants, and water-soluble dietary fibers. These compounds will be produced by higher plants. There was not enough attention at present to increasing content of micronutrients in edible parts of crops candidates for CELSS. We suggested to add the new crops to this list. 1. Barley -is the best crop for including to food crops (wheat, rice, soybean). Many of the health effects of barley are connected to dietary fibers beta-glucan of barley grains. Bar-ley is the only seed from cereals including wheat with content of all eight tocopherols (vitamin E, important antioxidant). Barley grains contain much greater amounts of phenolic compounds (potential antioxidant activities) than other cereal grains. Considerable focus is on supplement-ing wheat-based breads with barley to introduce the inherent nutritional advantages of barley flour, currently only 20We have selected and tested during 5 generations two high productive barley lines -1-K-O and 25-K-O. Our investigations (special breeding program for improving grain quality of barley) are in progress. 2. Volatile crops. Young leaves and shoots of these crops are edible and have a piquant taste. A lot of organic volatile compounds, oils, vitamins, antioxidants are in their biomass. These micronutrients are useful for good appetite and health of the crew. We have investigated 11 species: basil (Ocimum basilicum), hyssop (Hyssopus officinalis), marjoram (Origanum majorana), sweet-Mary (Melissa officinalis), common thyme (Thymus vulgaris), creeping thyme (Thymus serpyllum), summer savory (Satureja hortensis), catnip (Nepeta cataria), rue (Ruta graveolens), coriander (Coriandrum Ativum), sulfurwort (Levisticum officinale). These

  18. Integrated crop protection as a system approach

    NARCIS (Netherlands)

    Haan, de J.J.; Wijnands, F.G.; Sukkel, W.

    2005-01-01

    New farming systems in vegetable production are required as demands for high quality products that do not pollute the environment are rising, and production risks are large and incomes low. The methodology of prototyping new systems is described, especially the themes, parameters and target values c

  19. Some dynamic problems of rotating windmill systems

    Science.gov (United States)

    Dugundji, J.

    1976-01-01

    The basic whirl stability of a rotating windmill on a flexible tower is reviewed. Effects of unbalance, gravity force, gyroscopic moments, and aerodynamics are discussed. Some experimental results on a small model windmill are given.

  20. Increasing cropping system diversity balances productivity, profitability and environmental health

    Science.gov (United States)

    Balancing productivity, profitability, and environmental health is a key challenge for agricultural sustainability. Most crop production systems in the United States are characterized by low species and management diversity, high use of fossil energy and agrichemicals, and can have large negative im...

  1. Hyperspectral remote sensing analysis of short rotation woody crops grown with controlled nutrient and irrigation treatments

    Energy Technology Data Exchange (ETDEWEB)

    Im, Jungho; Jensen, John R.; Coleman, Mark; Nelson, Eric

    2009-08-01

    Abstract - Hyperspectral remote sensing research was conducted to document the biophysical and biochemical characteristics of controlled forest plots subjected to various nutrient and irrigation treatments. The experimental plots were located on the Savannah River Site near Aiken, SC. AISA hyperspectral imagery were analysed using three approaches, including: (1) normalized difference vegetation index based simple linear regression (NSLR), (2) partial least squares regression (PLSR) and (3) machine-learning regression trees (MLRT) to predict the biophysical and biochemical characteristics of the crops (leaf area index, stem biomass and five leaf nutrients concentrations). The calibration and cross-validation results were compared between the three techniques. The PLSR approach generally resulted in good predictive performance. The MLRT approach appeared to be a useful method to predict characteristics in a complex environment (i.e. many tree species and numerous fertilization and/or irrigation treatments) due to its powerful adaptability.

  2. Residue and soil carbon sequestration in relation to crop yield as affected by irrigation, tillage, cropping system and nitrogen fertilization

    Science.gov (United States)

    Information on management practices is needed to increase surface residue and soil C sequestration to obtain farm C credit. The effects of irrigation, tillage, cropping system, and N fertilization were evaluated on the amount of crop biomass (stems and leaves) returned to the soil, surface residue C...

  3. Bound Motion of Bodies and Paticles in the Rotating Systems

    Science.gov (United States)

    Pardy, Miroslav

    2007-04-01

    The Lagrange theory of particle motion in the noninertial systems is applied to the Foucault pendulum, isosceles triangle pendulum and the general triangle pendulum swinging on the rotating Earth. As an analogue, planet orbiting in the rotating galaxy is considered as the giant galactic gyroscope. The Lorentz equation and the Bargmann-Michel-Telegdi equations are generalized for the rotation system. The knowledge of these equations is inevitable for the construction of LHC where each orbital proton “feels” the Coriolis force caused by the rotation of the Earth.

  4. Energy crops for biogas plants. Bavaria; Energiepflanzen fuer Biogasanlagen. Bayern

    Energy Technology Data Exchange (ETDEWEB)

    Aigner, A.; Biertuempel, A.; Conrad, M. (and others)

    2012-08-15

    For agriculturists in Bavaria (Federal Republic of Germany), the brochure under consideration provides recommendations on alternative crop rotation systems. With the help of these alternative cultivation systems, crop rotation with high yields in combination with high diversity, diversification and sustainability can be realized. Subsequently to the presentation of energy crops for the production of biogas, recommendations for the design of crop rotation are given. Other chapters of this booklet deal with ensilage and gas yields as well as the economics of energy crop cultivation.

  5. The impact of the cropping system management on soil erosion and fertility in Northeastern Romania

    Energy Technology Data Exchange (ETDEWEB)

    Jitareanu, G.; Ailincai, C.; Bucur, D.; Raus, L.; Filipov, F.; Cara, M.

    2009-07-01

    The mass of total carbon from Cambic Chernozem in the Moldavian Plain has recorded significant increases at higher than N{sub 1}40 P{sub 1}00 rates, in organo-mineral fertilization and in 4-year crop rotation, which included melioration plants of perennial grasses and legumes. In maize continuous cropping and wheat-maize rotation, very significant values of the carbon content were found only in the organo-mineral fertilization, in 4-year crop rotations + reserve field cultivated with perennial legumes and under N{sub 1}40 P{sub 1}00 fertilization. In comparison with 4-year crop rotations, in wheat-maize rotation with melioration plants (annual and perennial legumes and perennial grasses), the mean carbon content from soil has diminished from 18.6 to 16.4 C, g.Kg{sup -}1 and the content in mobile phosphorus decreased from 51.6 to 36.8 P-Al, mg.kg{sup -}1. The 40 year use of 3 and 4-year crop rotations has determined the increase in total carbon mass and mobile phosphorus from soil by 10% (1.7 C g-kg{sup -}1) and 31%, respectively (11.8 P-Al mg.kg{sup -}1), against maize continuous cropping. (Author) 6 refs.

  6. Soil pH and exchangeable cation responses to tillage and fertilizer in dryland cropping systems

    Science.gov (United States)

    Long-term use of nitrogen (N) fertilizers can lead to soil acidification and other chemical changes that can lower fertility. Here, we present near-surface (0-7.6 cm) soil chemistry data from 16 years of two different crop rotations in the US northern Great Plains: (1) continuous crop (CC; spring w...

  7. Crop rotation design in view of soilborne pathogen dynamics : a methodological approach illustrated with Sclerotium rolfsii and Fusarium oxysporum f.sp. cepae

    NARCIS (Netherlands)

    Leoni, C.

    2013-01-01

    Key words: Sclerotium rolfsii, Fusarium oxysporum f.sp. cepae, soilborne pathogens, crop rotation, population dynamic models, simulation.   During the last decades, agriculture went through an intensification process associated with an increased use of fossil fuel energy, which despite tempor

  8. Development of the Land-use and Agricultural Management Practice web-Service (LAMPS) for generating crop rotations in space and time

    Science.gov (United States)

    Agroecosystem models and conservation planning tools require spatially and temporally explicit input data about agricultural management operations. The Land-use and Agricultural Management Practices web-Service (LAMPS) provides crop rotation and management information for user-specified areas within...

  9. The impacts of land-use change from grassland to bioenergy Short Rotation Coppice (SRC) willow on the crop and ecosystem greenhouse gas balance

    Science.gov (United States)

    Harris, Z. M.; Taylor, G.; Alberti, G.; Dondini, M.; Smith, P.

    2014-12-01

    The aim of this research is to better understand the greenhouse gas balance of land-use transition to bioenergy cropping systems in a UK context. Given limited land availability, addressing the food-energy-water nexus remains a challenge, and it is imperative that bioenergy crops are sited appropriately and that competition with food crops is minimised. Initial analyses included an extensive literature review and meta-analysis with a focus on the effects of land-use change to bioenergy on soil carbon and GHGs. This data mining exercise allowed us to understand the current state of the literature and identify key areas of research which needed to be addressed. Significant knowledge gaps were identified, with particular uncertainty around transitions from grasslands and transitions to short rotation forestry. A paired site experiment was established on a commercial SRC willow plantation and grassland to measure soil and ecosystem respiration. Initial results indicate that willow was a net sink for CO2 in comparison to grassland which was a net source of CO2. This provides evidence that the GHG balance of transition to SRC bioenergy willow will potentially result in increased soil carbon, in the long-term. The empirical findings from this study have been combined with modelled estimates for the site to both test and validate the ECOSSE model. Initial comparisons show that the model is able to accurately predict the respiration occurring at the field site, suggesting that it is a valuable approach for up-scaling from point sites such as this to wider geographical areas, and for considering future climate scenarios. The spatial modelling outputs will be used to build a modelling tool for non-specialist users which will determine the GHG and soil carbon effects of changing land to bioenergy for UK. This work is based on the Ecosystem Land Use Modelling & Soil Carbon GHG Flux Trial (ELUM) project, which was commissioned and funded by the Energy Technologies Institute (ETI).

  10. NEW TRENDS IN AGRICULTURE - CROP SYSTEMS WITHOUT SOIL

    Directory of Open Access Journals (Sweden)

    Ioan GRAD

    2014-04-01

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

  11. How short rotation forest crops can be used for sustainable remediation of contaminated areas

    Energy Technology Data Exchange (ETDEWEB)

    Thiry, I.

    1996-09-18

    In large territories of the CIS, it becomes obvious from the factual consequences of the Chernobyl environmental contamination that no successful remediation actions can be achieved without considering realistic technical and economical issues. In these conditions, the Short Rotation Forestry concept for energy purposes is proposed as an alternative and integrated approach for the recovery of agricultural practices on waste farm land. This corrective option will be examined with respect to this ecological, economical, and social relevancy. Different aspects of the culture in contaminated areas and of energy production from biomass remain to be investigated, developed and validated in the light of radiation protection criteria. In particular, attention will be drawn on the opportunity of this new concept to be integrated in the development of the site remediation research activities at SCK.CEN.

  12. Multiple-cylindrical Electrode System for Rotational Electric Field Generation in Particle Rotation Applications

    Directory of Open Access Journals (Sweden)

    Prateek Benhal

    2015-07-01

    Full Text Available Lab-on-a-chip micro-devices utilizing electric field-mediated particle movement provide advantages over current cell rotation techniques due to the flexibility in configuring micro-electrodes. Recent technological advances in micro-milling, three-dimensional (3D printing and photolithography have facilitated fabrication of complex micro-electrode shapes. Using the finite-element method to simulate and optimize electric field induced particle movement systems can save time and cost by simplifying the analysis of electric fields within complex 3D structures. Here we investigated different 3D electrode structures to obtain and analyse rotational electric field vectors. Finite-element analysis was conducted by an electric current stationary solver based on charge relaxation theory. High-resolution data were obtained for three-, four-, six- and eight-cylindrical electrode arrangements to characterize the rotational fields. The results show that increasing the number of electrodes within a fixed circular boundary provides larger regions of constant amplitude rotational electric field. This is a very important finding in practice, as larger rotational regions with constant electric field amplitude make placement of cells into these regions, where cell rotation occurs, a simple task – enhancing flexibility in cell manipulation. Rotation of biological particles over the extended region would be useful for biotechnology applications which require guiding cells to a desired location, such as automation of nuclear transfer cloning.

  13. Amelioration of drought-induced negative responses by elevated CO2 in field grown short rotation coppice mulberry (Morus spp.), a potential bio-energy tree crop.

    Science.gov (United States)

    Sekhar, Kalva Madhana; Reddy, Kanubothula Sitarami; Reddy, Attipalli Ramachandra

    2017-02-25

    Present study describes the responses of short rotation coppice (SRC) mulberry, a potential bio-energy tree, grown under interactive environment of elevated CO2 (E) and water stress (WS). Growth in E stimulated photosynthetic performance in well-watered (WW) as well as during WS with significant increases in light-saturated photosynthetic rates (A Sat), water use efficiency (WUEi), intercellular [CO2], and photosystem-II efficiency (F V/F M and ∆F/F M') with concomitant reduction in stomatal conductance (g s) and transpiration (E) compared to ambient CO2 (A) grown plants. Reduced levels of proline, H2O2, and malondialdehyde (MDA) and higher contents of antioxidants including ascorbic acid and total phenolics in WW and WS in E plants clearly demonstrated lesser oxidative damage. Further, A plants showed higher transcript abundance and antioxidant enzyme activities under WW as well as during initial stages of WS (15 days). However, with increasing drought imposition (30 days), A plants showed down regulation of antioxidant systems compared to their respective E plants. These results clearly demonstrated that future increased atmospheric CO2 enhances the photosynthetic potential and also mitigate the drought-induced oxidative stress in SRC mulberry. In conclusion, mulberry is a potential bio-energy tree crop which is best suitable for short rotation coppice forestry-based mitigation of increased [CO2] levels even under intermittent drought conditions, projected to prevail in the fast-changing global climate.

  14. Evapotranspiration and crop coefficient of poplar and willow short-rotation coppice used as vegetation filter.

    Science.gov (United States)

    Guidi, Werther; Piccioni, Emiliano; Bonari, Enrico

    2008-07-01

    Ten-day evapotranspiration (ETc) and crop coefficient (k(c)) of willow and poplar SRC used as vegetation filter and grown under fertilised (F) and unfertilised (NF) conditions, were determined for two successive growing seasons using volumetric lysimeters. During the first growing season, total ETc observed was, respectively, 620 (NF)-1190 (F)mm in willow and 590 (NF)-725 (F) in poplar. During the second growing season, ETc showed a general increase, mainly in fertilised lysimeters where it ranged between 890 (NF)-1790 mm (F) in willow and 710 (NF)-1100 mm (NF) in poplar. kc reached in both years its maximum between the end of August and the beginning of September. In 2004 maximum kc ranged from 1.25-2.84 in willow and 1.06-1.90 in poplar, whereas in 2005 it ranged from 1.97-5.30 in willow and 1.71-4.28 in poplar. ETc seemed to be strongly correlated to plant development and mainly dependent on its nutritional status rather than on the differences between the species.

  15. Soil organic carbon assessments in cropping systems using isotopic techniques

    Science.gov (United States)

    Martín De Dios Herrero, Juan; Cruz Colazo, Juan; Guzman, María Laura; Saenz, Claudio; Sager, Ricardo; Sakadevan, Karuppan

    2016-04-01

    Introduction of improved farming practices are important to address the challenges of agricultural production, food security, climate change and resource use efficiency. The integration of livestock with crops provides many benefits including: (1) resource conservation, (2) ecosystem services, (3) soil quality improvements, and (4) risk reduction through diversification of enterprises. Integrated crop livestock systems (ICLS) with the combination of no-tillage and pastures are useful practices to enhance soil organic carbon (SOC) compared with continuous cropping systems (CCS). In this study, the SOC and its fractions in two cropping systems namely (1) ICLS, and (2) CCS were evaluated in Southern Santa Fe Province in Argentina, and the use of delta carbon-13 technique and soil physical fractionation were evaluated to identify sources of SOC in these systems. Two farms inside the same soil cartographic unit and landscape position in the region were compared. The ICLS farm produces lucerne (Medicago sativa Merrill) and oat (Avena sativa L.) grazed by cattle alternatively with grain summer crops sequence of soybean (Glicine max L.) and corn (Zea mays L.), and the farm under continuous cropping system (CCS) produces soybean and corn in a continuous sequence. The soil in the area is predominantly a Typic Hapludoll. Soil samples from 0-5 and 0-20 cm depths (n=4) after the harvest of grain crops were collected in each system and analyzed for total organic carbon (SOC, 0-2000 μm), particulate organic carbon (POC, 50-100 μm) and mineral organic carbon (MOC, <50 μm). Delta carbon-13 was determined by isotopic ratio mass spectrometry. In addition, a site with natural vegetation (reference site, REF) was also sampled for delta carbon-13 determination. ANOVA and Tukey statistical analysis were carried out for all data. The SOC was higher in ICLS than in CCS at both depths (20.8 vs 17.7 g kg-1 for 0-5 cm and 16.1 vs 12.7 g kg-1 at 0-20 cm, respectively, P<0.05). MOC was

  16. Research of optical rotation measurement system based on centroid algorithm

    Science.gov (United States)

    Cao, Junjie; Jia, Hongzhi; Shen, Xinrong; Jiang, Shixin

    2016-09-01

    An optical rotation measurement system based on digital signal processor, modulated laser, and step motor rotating stage is established. Centroid algorithm featured fast and simple calculation is introduced to process light signals with or without sample to obtain the optical rotating angle through the step difference between two centroids. The system performance is proved experimentally with standard quartz tubes and glucose solutions. After various measurements, the relative error and precision of the system are determined to 0.4% and 0.004°, which demonstrates the reliable repeatability and high accuracy of whole measurement system.

  17. Organic fertilization for soil improvement in a vegetable cropping system

    Science.gov (United States)

    Verhaeghe, Micheline; De Rocker, Erwin; De Reycke, Luc

    2016-04-01

    Vegetable Research Centre East-Flanders Karreweg 6, 9770 Kruishoutem, Belgium A long term trial for soil improvement by organic fertilization was carried out in Kruishoutem from 2001 till 2010 in a vegetable rotation (carrots - leek - lettuce (2/year) - cauliflower (2/year) - leek - carrots - lettuce (2/year) - cauliflower (2/year) - leek and spinach). The trial compared yearly applications of 30 m²/ha of three types of compost (green compost, vfg-compost and spent mushroom compost) with an untreated object which did not receive any organic fertilization during the trial timescale. The organic fertilization was applied shortly before the cropping season. Looking at the soil quality, effects of organic fertilization manifest rather slow. The first four years after the beginning of the trial, no increase in carbon content of the soil is detectable yet. Although, mineralization of the soil has increased. The effect on the mineralization is mainly visible in crops with a lower N uptake (e.g. carrots) leading to a higher nitrate residue after harvest. Effects on soil structure and compaction occur rather slowly although, during the first two cropping seasons compost applications increase the water retention capacity of the soil. Compost increases the pH of the soil from the first year on till the end of the trial in 2010. Thus, organic fertilization impedes acidification in light sandy soils. Also soil fertility benefits from compost by an increase in K-, Ca- and Mg- content in the soil from the second year on. After 10 years of organic fertilization, yield and quality of spinach were increased significantly (porganic fertilization.

  18. Global warming likely reduces crop yield and water availability of the dryland cropping systems in the U.S. central Great Plains

    Science.gov (United States)

    We investigated impacts of GCM-projected climate change on dryland crop rotations of wheat-fallow and wheat-corn-fallow in the Central Great Plains (Akron in Colorado, USA) using the CERES 4.0 crop modules in RZWQM2. The climate change scenarios for CO2, temperature, and precipitation were produced ...

  19. Neutral hydrolysable sugars, OC and N content across soil aggregate size fractions, as an effect of two different crop rotations

    Science.gov (United States)

    Angeletti, Carlo; Giannetta, Beatrice; Kölbl, Angelika; Monaci, Elga; Kögel-Knabner, Ingrid; Vischetti, Costantino

    2016-04-01

    This paper presents the results regarding the effects of two 13 years long crop rotations, on the composition of mineral associated neutral sugars, organic carbon (OC) and N concentration, across different aggregate size fractions. The two cropping sequences were characterized by different levels of N input from plant residues and tillage frequency. We also analysed the changes that occurred in soil organic matter (SOM) chemical composition following the cultivation in the two soils of winter wheat and chickpea on the same soils. The analysis of OC and N content across soil aggregate fractions allowed getting an insight into the role played by SOM chemical composition in the formation of organo-mineral associations, while neutral sugars composition provided information on mineral associated SOM origin and decomposition processes, as pentoses derive mostly from plant tissues and hexoses are prevalently of microbial origin. Soil samples were collected from two adjacent fields, from the 0-10 cm layer, in November 2011 (T0). For 13 years before the beginning of the experiment, one soil was cultivated mostly with alfalfa (ALF), while a conventional cereal-sunflower-legume rotation (CON) was carried out on the other. Winter wheat and chickpea were sown on the two soils during the following 2 growing seasons and the sampling was repeated after 18 months (T1). A combination of aggregates size and density fractionation was used to isolate OM associated with mineral particles in: macro-aggregates (>212 μm), micro-aggregates ( 63 μm) and silt and clay size particles (sugar monomers was measured via GC-FID: rhamnose, fucose, ribose, arabinose, xylose, mannose, galactose, glucose. OC and N contents were higher in ALF as compared to CON for every aggregate fraction, both at T0 and T1. During the 18-months cultivation experiment macro aggregates OC concentration increased in ALF while decreasing in CON. During the same period silt and clay size particles OC concentration

  20. Short rotation coppice culture of willows and poplars as energy crops on metal contaminated agricultural soils.

    Science.gov (United States)

    Ruttens, Ann; Boulet, Jana; Weyens, Nele; Smeets, Karen; Adriaensen, Kristin; Meers, Erik; Van Slycken, Stijn; Tack, Filip; Meiresonne, Linda; Thewys, Theo; Witters, Nele; Carleer, Robert; Dupae, Joke; Vangronsveld, Jaco

    2011-01-01

    Phytoremediation, more precisely phytoextraction, has been placed forward as an environmental friendly remediation technique, that can gradually reduce increased soil metal concentrations, in particular the bioavailable fractions. The aim of this study was to investigate the possibilities of growing willows and poplars under short rotation coppice (SRC) on an acid, poor, sandy metal contaminated soil, to combine in this way soil remediation by phytoextraction on one hand, and production of biomass for energy purposes on the other. Above ground biomass productivities were low for poplars to moderate for willows, which was not surprising, taking into account the soil conditions that are not very favorable for growth of these trees. Calculated phytoextraction efficiency was much longer for poplars than these for willows. We calculated that for phytoextraction in this particular case it would take at least 36 years to reach the legal threshold values for cadmium, but in combination with production of feedstock for bioenergy processes, this type of land use can offer an alternative income for local farmers. Based on the data of the first growing cycle, for this particular case, SRC of willows should be recommended.

  1. Eleven-year results on soft and durum wheat crops grown in an organic and in a conventional low input cropping system

    Directory of Open Access Journals (Sweden)

    Paolo Benincasa

    2016-05-01

    Full Text Available Eleven-year results on yields and apparent balances of organic matter and nitrogen (N are reported for soft and durum wheat crops grown in the BIOSYST long-term experiment for the comparison between an organic and a conventional low-input system in Central Italy. The N supply to organic wheat consisted of 40 kg N ha–1 as poultry manure plus the supposed residual N left by green manures carried out before the preceding summer vegetable, while the N supply to conventional wheat consisted of 80 kg N ha–1 as mineral fertilisers, split in two applications of 40 kg ha–1 each, at tillering and pre-shooting. In every year, above ground biomass and N accumulation of each wheat species, including weeds, and the partitioning between grain yield and crop residues were determined. Apparent dry matter and N balances were calculated at the end of each crop cycle by taking into account the amounts of dry matter and N supplied to the system as fertilisers, and those removed with grain yield. Soft wheat yielded more than durum wheat. For both species, grain yield and protein content were more variable across years and generally lower in the organic than in the conventional system. In both systems, grain yield of both species resulted negatively correlated with fall-winter rainfall, likely for its effect on soil N availability. Both species caused a lower return of biomass and a higher soil N depletion in the organic than in the conventional system. Our experiment confirmed that winter wheat can help exploit the soil N availability and reduce N leaching in fall winter, especially after summer vegetables, but in stockless or stock-limited organic systems it needs to be included in rotations where soil fertility is restored by fall winter green manures to be carried out before summer crops.

  2. Theory of symmetry for a rotational relativistic Birkhoff system

    Institute of Scientific and Technical Information of China (English)

    罗绍凯; 陈向炜; 郭永新

    2002-01-01

    The theory of symmetry for a rotational relativistic Birkhoff system is studied. In terms of the invariance of therotational relativistic Pfaff-Birkhoff-D'Alembert principle under infinitesimal transformations, the Noether symmetriesand conserved quantities of a rotational relativistic Birkhoff system are given. In terms of the invariance of rotationalrelativistic Birkhoff equations under infinitesimal transformations, the Lie symmetries and conserved quantities of therotational relativistic Birkhoff system are given.

  3. Illicit crops: A look from the national accounts system

    Directory of Open Access Journals (Sweden)

    Carmen Lucía Bazzani C.

    2012-07-01

    Full Text Available This article presents an analysis of the evolution of illicit crops in Colombia through the National Accounts System, which provides a basis for the study of transactions and the use of the product in an economy. Through the input-output methodology it is shown that, thanks to the drug policy action developed by the national government, its importance in generation of value added has been changing and decreasing over time.

  4. Rotational stability of different hip revision systems

    Directory of Open Access Journals (Sweden)

    M. Thomsen

    2014-01-01

    Full Text Available The authors present an experimental investigation that compares the primary rotational fixation of 4 revision stems. Methods: Each stem was implanted into 4 synthetic femora. Micromotion of stem and bone was measured at defined sites under torque application. Femoral neck osteotomy and AAOS type I and III defects were simulated by reproducible saw lines. Results: Up to a type I defect, all implants are capable of bridging the substance loss in a rotationally stable manner. The relative movements show a dependence both on the bone defect and on implant design. Even within the basic design types clear differences (p < 0.0001 are partially observable. Major differences were seen in type III defects. Whereas the conical stem designs had the ability to bridge the extensive defect the cylindric shapes showed no rotationally stability. Conclusion: As the major fixation area the femoral isthmus plays a decisive role for all tested stems. Due to enormous and partly selective load transmission of the conical stems the cylindrical designs is good for type I defects. In case of an extensive substance loss the decision should be a conical implant.

  5. THE INFLUENCE OF MINIMUM TILLAGE SYSTEMS UPON THE SOIL PROPERTIES, YIELD AND ENERGY EFFICIENCY IN SOME ARABLE CROPS

    Directory of Open Access Journals (Sweden)

    Teodor RUSU

    2006-05-01

    Full Text Available The paper presents the influence of the conventional ploughing tillage technology in comparison with the minimum tillage, upon the soil properties, weed control, yield and energy efficiency in the case of maize (Zea mays L., soyabean (Glycine hispida L. and winter wheat (Triticum aestivum L. in a three years crop rotation. For all cultures within the crop rotation, the weed encroachment is maximum for the disc harrow and rotary harrow soil tillage, followed by the chisel and paraplow. The weed encroachment is minimum for the conventional ploughing tillage technology. The results of investigations showed that the yield is a conclusion soil tillage systems influence on soil properties, plant density assurance and on weed control.

  6. A methodological approach for deriving regional crop rotations as basis for the assessment of the impact of agricultural strategies using soil erosion as example.

    Science.gov (United States)

    Lorenz, Marco; Fürst, Christine; Thiel, Enrico

    2013-09-01

    Regarding increasing pressures by global societal and climate change, the assessment of the impact of land use and land management practices on land degradation and the related decrease in sustainable provision of ecosystem services gains increasing interest. Existing approaches to assess agricultural practices focus on the assessment of single crops or statistical data because spatially explicit information on practically applied crop rotations is mostly not available. This provokes considerable uncertainties in crop production models as regional specifics have to be neglected or cannot be considered in an appropriate way. In a case study in Saxony, we developed an approach to (i) derive representative regional crop rotations by combining different data sources and expert knowledge. This includes the integration of innovative crop sequences related to bio-energy production or organic farming and different soil tillage, soil management and soil protection techniques. Furthermore, (ii) we developed a regionalization approach for transferring crop rotations and related soil management strategies on the basis of statistical data and spatially explicit data taken from so called field blocks. These field blocks are the smallest spatial entity for which agricultural practices must be reported to apply for agricultural funding within the frame of the European Agricultural Fund for Rural Development (EAFRD) program. The information was finally integrated into the spatial decision support tool GISCAME to assess and visualize in spatially explicit manner the impact of alternative agricultural land use strategies on soil erosion risk and ecosystem services provision. Objective of this paper is to present the approach how to create spatially explicit information on agricultural management practices for a study area around Dresden, the capital of the German Federal State Saxony.

  7. Greenhouse gas flux and crop productivity after 10 years of reduced and no tillage in a wheat-maize cropping system.

    Science.gov (United States)

    Tian, Shenzhong; Wang, Yu; Ning, Tangyuan; Zhao, Hongxiang; Wang, Bingwen; Li, Na; Li, Zengjia; Chi, Shuyun

    2013-01-01

    Appropriate tillage plays an important role in mitigating the emissions of greenhouse gases (GHG) in regions with higher crop yields, but the emission situations of some reduced tillage systems such as subsoiling, harrow tillage and rotary tillage are not comprehensively studied. The objective of this study was to evaluate the emission characteristics of GHG (CH4 and N2O) under four reduced tillage systems from October 2007 to August 2009 based on a 10-yr tillage experiment in the North China Plain, which included no-tillage (NT) and three reduced tillage systems of subsoil tillage (ST), harrow tillage (HT) and rotary tillage (RT), with the conventional tillage (CT) as the control. The soil under the five tillage systems was an absorption sink for CH4 and an emission source for N2O. The soil temperature positive impacted on the CH4 absorption by the soils of different tillage systems, while a significant negative correlation was observed between the absorption and soil moisture. The main driving factor for increased N2O emission was not the soil temperature but the soil moisture and the content of nitrate. In the two rotation cycle of wheat-maize system (10/2007-10/2008 and 10/2008-10/2009), averaged cumulative uptake fluxes of CH4 under CT, ST, HT, RT and NT systems were approximately 1.67, 1.72, 1.63, 1.77 and 1.17 t ha(-1) year(-1), respectively, and meanwhile, approximately 4.43, 4.38, 4.47, 4.30 and 4.61 t ha(-1) year(-1) of N2O were emitted from soil of these systems, respectively. Moreover, they also gained 33.73, 34.63, 32.62, 34.56 and 27.54 t ha(-1) yields during two crop-rotation periods, respectively. Based on these comparisons, the rotary tillage and subsoiling mitigated the emissions of CH4 and N2O as well as improving crop productivity of a wheat-maize cropping system.

  8. Land and Water Use in Rice-upland Crop Rotation Areas in Lower Ili River Basin, Kazakhstan

    Institute of Scientific and Technical Information of China (English)

    SHIMIZU Katsuyuki; KITAMURA Yoshinobu; ANZAI Toshihiko; KUBOTA Jumpei

    2010-01-01

    The lower Ili River Basin is located in semi-arid area, and the annual rainfall is 177 mm. Therefore, the irrigation is inevitable for agriculture. Large-scale irrigated agriculture had been developed since 1960's in the lower parts of the river and the total irrigated area is about 32 000 hm2. In the project area, the paddy nee-upland crop rotation has been practiced. Due to the domestic water use for hydropower and agriculture as well as water use among riparian countries, the deficit of water for agriculture in the lower part has been concerned. The authors, therefore, conducted the field survey and water balance analysis of the Akdara irrigation project in the lower Ili River Basin in order to assess the land and water uses. Moreover, the impact of the water use on water environment to the basin was analyzed. The following results were obtained as following (1) the groundwater level in the irrigated district varied from 1.5 m to 3.5 m through year. (2) 1970's groundwater level was drastically raised from 8 m to 3 m and the groundwater had been recharged in this period. (3) Water use efficiency of agriculture, which is the ratio of total evapotranspiration to the total water withdrawal was as low as 0.23.

  9. Soil carbon, after 3 years, under short-rotation woody crops grown under varying nutrient and water availability

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, Felipe G. [USDA Forest Service, Southern Research Station, Forestry Sciences Laboratory, 3041 Cornwallis Road, Research Triangle Park, NC 27709 (United States); Coleman, Mark [USDA Forest Service, Southern Research Station, Savannah River Institute, P.O. Box 700, New Ellenton, SC 29809 (United States); Garten, Charles T. Jr.; Luxmoore, Robert J.; Wullschleger, Stan D. [Environmenal Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 38731 (United States); Stanturf, John A. [USDA Forest Service, Southern Research Station, Forestry Sciences Laboratory, 320 Green Street, Athens, GA 30602 (United States); Trettin, Carl [USDA Forest Service, Southern Research Station, Center for Forested Wetlands Research, 2730 Savannah Highway, Charleston, SC 29414 (United States)

    2007-11-15

    Soil carbon contents were measured on a short-rotation woody crop study located on the US Department of Energy's Savannah River Site outside Aiken, SC. This study included fertilization and irrigation treatments on five tree genotypes (sweetgum, loblolly pine, sycamore and two eastern cottonwood clones). Prior to study installation, the previous pine stand was harvested and the remaining slash and stumps were pulverized and incorporated 30 cm into the soil. One year after harvest soil carbon levels were consistent with pre-harvest levels but dropped in the third year below pre-harvest levels. Tillage increased soil carbon contents, after three years, as compared with adjacent plots that were not part of the study but where harvested, but not tilled, at the same time. When the soil response to the individual treatments for each genotype was examined, one cottonwood clone (ST66), when irrigated and fertilized, had higher total soil carbon and mineral associated carbon in the upper 30 cm compared with the other tree genotypes. This suggests that root development in ST66 may have been stimulated by the irrigation plus fertilization treatment. (author)

  10. Soil carbon after three years under short rotation woody crops grown under varying nutrient and water availability

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, Felipe G. [USDA Forest Service; Coleman, Mark [USDA Forest Service; Garten Jr, Charles T [ORNL; Luxmoore, Robert J [ORNL; Stanturf, J. A. [USDA Forest Service; Trettin, Carl [USDA Forest Service; Wullschleger, Stan D [ORNL

    2007-01-01

    Soil carbon contents were measured on a short-rotation woody crop study located on the US Department of Energy's Savannah River Site outside Aiken, SC. This study included fertilization and irrigation treatments on five tree genotypes (sweetgum, loblolly pine, sycamore and two eastern cottonwood clones). Prior to study installation, the previous pine stand was harvested and the remaining slash and stumps were pulverized and incorporated 30 cm into the soil. One year after harvest soil carbon levels were consistent with pre-harvest levels but dropped in the third year below pre-harvest levels. Tillage increased soil carbon contents, after three years, as compared with adjacent plots that were not part of the study but where harvested, but not tilled, at the same time. When the soil response to the individual treatments for each genotype was examined, one cottonwood clone (ST66), when irrigated and fertilized, had higher total soil carbon and mineral associated carbon in the upper 30 cm compared with the other tree genotypes. This suggests that root development in ST66 may have been stimulated by the irrigation plus fertilization treatment.

  11. Estimating relationships among water use, nitrogen uptake and biomass production in a short-rotation woody crop plantation

    Science.gov (United States)

    Ouyang, Y.

    2015-12-01

    Short-rotation woody crop has been identified as one of the best feedstocks for bioenergy production due to their fast-growth rates. However, the biomass production, nutrient uptake, and water use efficiency under adverse environmental condition are still poorly understood. In this study, a computer model was developed to undertake these issues using STELLA (Structural Thinking and Experiential Learning Laboratory with Animation) software. Two simulation scenarios were employed: one was to quantify the mechanisms of water use, nitrogen uptake and biomass production in a eucalypt plantation under the normal soil conditions, the other was to estimate the same mechanisms under the wet and dry soil conditions. In general, the rates of evaporation, transpiration, evapotranspiration (ET), and root water uptake were in the following order: ET > root uptake > leaf transpiration > soil evaporation. A profound discrepancy in water use was observed between the wet and dry soil conditions. Leaching of nitrate-N and soluble organic N depended not only on soil N content but also on rainfall rate and duration. The yield of biomass from the eucalypt was primarily regulated by water availability in a fertilized plantation.

  12. Forms of phosphorus in an oxisol under different soil tillage systems and cover plants in rotation with maize

    Directory of Open Access Journals (Sweden)

    Arminda Moreira de Carvalho

    2014-06-01

    Full Text Available Phosphorus fractions play a key role in sustaining the productivity of acid-savanna Oxisols and are influenced by tillage practices. The aim of this study was to quantify different P forms in an Oxisol (Latossolo Vermelho-Amarelo from the central savanna region of Brazil under management systems with cover crops in maize rotation. Three cover crops (Canavalia brasiliensis, Cajanus cajan (L., and Raphanus sativus L. were investigated in maize rotation systems. These cover crops were compared to spontaneous vegetation. The inorganic forms NaHCO3-iP and NaOH-iP represented more than half of the total P in the samples collected at the depth of 5-10 cm during the rainy season when the maize was grown. The concentration of inorganic P of greater availability (NaHCO3-iP and NaOH-iP was higher in the soil under no-tillage at the depth of 5-10 cm during the rainy season. Concentrations of organic P were higher during the dry season, when the cover crops were grown. At the dry season, organic P constituted 70 % of the labile P in the soil planted to C. cajan under no-tillage. The cover crops were able to maintain larger fractions of P available to the maize, resulting in reduced P losses to the unavailable pools, mainly in no-tillage systems.

  13. Fertilization regimes affect the soil biological characteristics of a sudangrass and ryegrass rotation system.

    Science.gov (United States)

    Li, WenXi; Lu, JianWei; Li, FangBai; Wang, Yan; Lu, JunMing; Li, XiaoKun

    2011-06-01

    The sudangrass (Sorghum sudanense) and ryegrass (Lolium multiflorum L.) rotation is an intensive and new cropping system in Central China. Nutrient management practices in this rotation system may influence soil fertility, the important aspects of which are soil biological properties and quality. As sensitive soil biological properties and quality indicators, soil microbial community activity, microbial biomass, enzyme activities, soil organic matter (SOM) and total N resulting from different fertilization regimes in this rotation system were studied through a four-year field experiment from April 2005 to May 2009. Treatments included control (CK), fertilizer phosphorus and potassium (PK), fertilizer nitrogen and potassium (NK), fertilizer nitrogen and phosphorus (NP) and a fertilizer nitrogen, phosphorus and potassium combination (NPK). Soil microbial community activities in the NK, NP and NPK treatments were significantly lower than those in the CK and PK treatments after the sudangrass and ryegrass trial. The highest microbial biomass C, microbial biomass N, SOM, total N, sucrase and urease activities were found in the NPK treatment, and these soil quality indicators were significantly higher in the NK, NP and NPK treatments than in the PK and CK treatments. Soil microbial biomass and enzyme activities were positively associated with SOM in the sudangrass and ryegrass rotation system, indicating that fertilization regimes, especially N application, reduced microbial community activity in the soil. Proper fertilization regimes will increase microbial biomass, enzyme activity and SOM and improve soil fertility.

  14. The Controlled Ecological Life Support System Antarctic Analog Project: Prototype Crop Production and Water Treatment System Performance

    Science.gov (United States)

    Bubenheim, David L.; Flynn, Michael T.; Bates, Maynard; Schlick, Greg; Kliss, Mark (Technical Monitor)

    1997-01-01

    The Controlled Ecological Life Support System (CELSS) Antarctic Analog Project (CAAP), is a joint endeavor between the National Science Foundation, Office of Polar Programs (NSF-OPP) and the NASA. The fundamental objective is to develop, deploy, and operate a testbed of advanced life support technologies at the Amundsen-Scott South Pole Station that enable the objectives of both the NSF and NASA. The functions of food production, water purification, and waste treatment, recycle and reduction provided by CAAP will improve the quality of life for the South Pole inhabitants, reduce logistics dependence, enhance safety and minimize environmental impacts associated with human presence on the polar plateau. Because of the analogous technical, scientific, and mission features with Planetary missions such as a mission to Mars, CAAP provides NASA with a method for validating technologies and overall approaches to supporting humans. Prototype systems for sewage treatment, water recycle and crop production are being evaluated at Ames Research Center. The product water from sewage treatment using a Wiped-Film Rotating Disk is suitable for input to the crop production system. The crop production system has provided an enhanced level of performance compared with projected performance for plant-based life support: an approximate 50% increase in productivity per unit area, more than a 65% decrease in power for plant lighting, and more than a 75% decrease in the total power requirement to produce an equivalent mass of edible biomass.

  15. Less or More Intensive Crop Arable Systems of Alentejo Region of Portugal: what is the sustainable option?

    Directory of Open Access Journals (Sweden)

    Carlos Marques

    2015-03-01

    Full Text Available Competitiveness of traditional arable crop system of Alentejo region of Portugal has been questioned for long. Discussion and research on the sustainability of the system has evolved on two contrasted alternative options for production technologies to traditional system. On the one hand reduced and no tillage systems aim to more extensive technical operations reducing costs and maintaining production, or even to increase it in the long run as soil fertility improves. On the other hand, input intensification using irrigation, as a complement in the last stage of crop cycle or always when needed, aimed to increase system production levels. To evaluate competitiveness and sustainability of arable crop system we evaluated traditional rotation technology and alternative no tillage and irrigation systems and analyze their farm economic results as well as their energy efficiency and environmental impacts. The analysis of the impact of no tillage and irrigation on arable land production system showed that both alternatives contributed to cost savings and profit earnings, energy savings and reduced GHG emissions, increasing physical and economic factor efficiency. Research and technological development of both options are worthwhile to promote competitiveness and sustainability of arable crop production systems of the Alentejo region in Portugal.

  16. Direct and indirect impacts of crop-livestock organization on mixed crop-livestock systems sustainability: a model-based study.

    Science.gov (United States)

    Sneessens, I; Veysset, P; Benoit, M; Lamadon, A; Brunschwig, G

    2016-11-01

    Crop-livestock production is claimed more sustainable than specialized production systems. However, the presence of controversial studies suggests that there must be conditions of mixing crop and livestock productions to allow for higher sustainable performances. Whereas previous studies focused on the impact of crop-livestock interactions on performances, we posit here that crop-livestock organization is a key determinant of farming system sustainability. Crop-livestock organization refers to the percentage of the agricultural area that is dedicated to each production. Our objective is to investigate if crop-livestock organization has both a direct and an indirect impact on mixed crop-livestock (MC-L) sustainability. In that objective, we build a whole-farm model parametrized on representative French sheep and crop farming systems in plain areas (Vienne, France). This model permits simulating contrasted MC-L systems and their subsequent sustainability through the following indicators of performance: farm income, production, N balance, greenhouse gas (GHG) emissions (/kg product) and MJ consumption (/kg product). Two MC-L systems were simulated with contrasted crop-livestock organizations (MC20-L80: 20% of crops; MC80-L20: 80% of crops). A first scenario - constraining no crop-livestock interactions in both MC-L systems - permits highlighting that crop-livestock organization has a significant direct impact on performances that implies trade-offs between objectives of sustainability. Indeed, the MC80-L20 system is showing higher performances for farm income (+44%), livestock production (+18%) and crop GHG emissions (-14%) whereas the MC20-L80 system has a better N balance (-53%) and a lower livestock MJ consumption (-9%). A second scenario - allowing for crop-livestock interactions in both MC20-L80 and MC80-L20 systems - stated that crop-livestock organization has a significant indirect impact on performances. Indeed, even if crop-livestock interactions permit

  17. Designing Cropping Systems for Metal-Contaminated Sites: A Review

    Institute of Scientific and Technical Information of China (English)

    TANG Ye-Tao; CHEN Tong-Bin; G. ECHEVARRIA; T. STERCKEMAN; M. O. SIMONNOT; J. L. MOREL; DENG Teng-Hao-Bo; WU Qi-Hang; WANG Shi-Zhong; QIU Rong-Liang; WEI Ze-Bin; GUO Xiao-Fang; WU Qi-Tang; LEI Mei

    2012-01-01

    Considering that even contaminated soils are a potential resource for agricultural production,it is essential to develop a set of cropping systems to allow a safe and sustainable agriculture on contaminated lands while avoiding any transfer of toxic trace elements to the food chain.In this review,three main strategies,i.e.,phytoexclusion,phytostabilization,and phytoextraction,are proposed to establish cropping systems for production of edible and non-edible plants,and for extraction of elements for industrial use.For safe production of food crops,the selection of low-accumulating plants/cultivars and the application of soil amendments are of vital importance.Phytostabilization using non-food energy and fiber plants can provide additional renewable energy sources and economic benefit with minimum cost of agriculturai measures.Phytoextracting trace elements (e.g.,As,Cd,Ni,and Zn) using hyperaccumulator species is more suitable for slightly and moderately polluted sites,and phytomining of Ni from serpentine soils has shown a great potential to extract Ni-containing bio-ores of economic interests.We conclude that appropriate combinations of soil types,plant species/cultivars,and agronomic practices can restrict trace metal transfer to the food chain and/or extract energy and metals of industrial use and allow safe agricultural activities.

  18. Finite Element Computational Dynamics of Rotating Systems

    Directory of Open Access Journals (Sweden)

    Jaroslav Mackerle

    1999-01-01

    Full Text Available This bibliography lists references to papers, conference proceedings and theses/dissertations dealing with finite element analysis of rotor dynamics problems that were published in 1994–1998. It contains 319 citations. Also included, as separate subsections, are finite element analyses of rotor elements – discs, shafts, spindles, and blades. Topics dealing with fracture mechanics, contact and stability problems of rotating machinery are also considered in specific sections. The last part of the bibliography presents papers dealing with specific industrial applications.

  19. [Effect of conservation tillage on weeds in a rotation system on the Loess Plateau of eastern Gansu, Northwest China].

    Science.gov (United States)

    Zhao, Yu-xin; Lu, Jiao-yun; Yang, Hui-min

    2015-04-01

    A field study was conducted to investigate the influences of no-tillage, stubble retention and crop type on weed density, species composition and community feature in a rotation system (winter wheat-common vetch-maize) established 12 years ago on the Loess Plateau of eastern Gansu. This study showed that the weed species composition, density and community feature varied with the change of crop phases. No-tillage practice increased the weed density at maize phase, while rotation with common vetch decreased the density in the no-tillage field. Stubble retention reduced the weed density under maize phase and the lowest density was observed in the no-tillage plus stubble retention field. No-tillage practice significantly increased the weed species diversity under winter wheat phase and decreased the diversity under common vetch phase. At maize phase, a greater species diversity index was observed in the no-tillage field. These results suggested that no-tillage practice and stubble retention possibly suppress specific weeds with the presence of some crops and crop rotation is a vital way to controlling weeds in a farming system.

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

    Science.gov (United States)

    Moraru, P. I.; Rusu, T.

    2012-04-01

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

  1. Interacting galaxies: co-rotating and counter-rotating systems with tidal tails

    CERN Document Server

    Mesa, Valeria; Alonso, Sol; Coldwell, Georgina; Lambas, Diego G

    2013-01-01

    We analyse interacting galaxy pairs with evidence of tidal features in the Sloan Digital Sky Survey Data Release 7 (SDSS-DR7). The pairs were selected within $z<0.1$ by requiring a projected separation $r_p < 50 \\kpc$ and relative radial velocity $\\Delta V < 500 \\kms$. We complete spectroscopic pairs using galaxies with photometric redshifts considering $\\Delta V_{phot} < 6800 \\kms$, taking into account the mean photometric redshift uncertainty. We classify by visual inspection pairs of spirals into co-rotating and counter-rotating systems. For a subsample of non-AGN galaxies, counter-rotating pairs have larger star formation rates, and a higher fraction of young, star-forming galaxies. These effects are enhanced by restricting to $r_p < 12 \\kpc$. The distributions of $C$, $D_n(4000)$ and $(M_u-M_r)$ for AGN galaxies show that counter-rotating hosts have bluer colours and younger stellar population than the co-rotating galaxies although the relative fractions of Seyfert, Liner, Composite and Am...

  2. Carbon sequestration in maize and grass dominant cropping systems in Flanders

    Science.gov (United States)

    Van De Vreken, Philippe; Gobin, Anne; Merckx, Roel

    2014-05-01

    Sources of soil organic matter (SOM) input to the soil in agro-ecosystems are typically crop residues. The question arises how removing crop residues from a field influences soil carbon sequestration. We investigated four long-term maize and grass dominant cropping systems each with a different residue management. Under silage maize (SM) all stover is removed from the field and only a stubble remains, whereas under grain maize (GM) only the grains are harvested and all stover is returned to the soil. Fields with a history of at least 15 consecutive years of either SM (with or without a second annual crop of Italian ryegrass) or GM, and fields under permanent grass were selected from a geodatabase that covers 15 years of crop rotation for all of the ca. 500,000 agricultural fields in Flanders. For each cropping system 10 fields were sampled (40 in total) following the area-frame randomized soil sampling (AFRSS) protocol (Stolbovoy et al., 2007). For 6 out of 10 fields only the topsoil was sampled (0-30 cm), whereas for the 4 other fields both topsoil and subsoil (30-60 cm and 60-90 cm) were sampled. The total soil organic carbon (SOC) and nitrogen content and the stable carbon isotope ratio (13C/12C) were determined for each soil sample. From each field 1 topsoil sample was fractionated by the Zimmermann fractionation procedure (Zimmermann et al., 2007) which distinguishes between 5 different SOC fractions (POM, DOC, silt and clay associated SOC, chemically resistant SOC, SOC associated with sand fraction). Besides analysis of the SOC and nitrogen content of each fraction, the origin of the carbon was determined through isotope-ratio mass spectrometry. Although there was no significant difference between SM and GM regarding the total SOC stock for the upper 30 cm (ca. 75 à 80 Mg C.ha-1), fields under continuous GM contained in the 0-30 cm layer 60% more maize-derived C4-SOC as compared to fields under continuous SM (ca. 14 and 9 Mg C.ha-1 respectively). Significant

  3. Crop yield, root growth, and nutrient dynamics in a conventional and three organic cropping systems with different levels of external inputs and N re-cycling through fertility building crops

    DEFF Research Database (Denmark)

    Thorup-Kristensen, Kristian; Dresbøll, Dorte Bodin; Kristensen, Hanne Lakkenborg

    2012-01-01

    systems based on fertility building crops (green manures and catch crops). In short, the main distinctions were not observed between organic and conventional systems (i.e. C vs. O1, O2 and O3), but between systems based mainly on nutrient import vs. systems based mainly on fertility building crops (C...

  4. Crop diversification, tillage, and management system influences on spring wheat yield and soil water use

    Science.gov (United States)

    Depleted soil quality, decreased water availability, and increased weed competition constrain spring wheat production in the northern Great Plains. Integrated crop management systems are necessary for improved crop productivity. We conducted a field experiment from 2004-2010 comparing productivity...

  5. Development of an unmanned agricultural robotics system for measuring crop conditions for precision aerial application

    Science.gov (United States)

    An Unmanned Agricultural Robotics System (UARS) is acquired, rebuilt with desired hardware, and operated in both classrooms and field. The UARS includes crop height sensor, crop canopy analyzer, normalized difference vegetative index (NDVI) sensor, multispectral camera, and hyperspectral radiometer...

  6. Response of Sorghum (Sorghum bicolor L.) to Residual Phosphate in Soybean-Sorghum and Maize-Sorghum Crop Rotation Schemes on Two Contrasting Nigerian Alfisols

    OpenAIRE

    2016-01-01

    The effectiveness of finely ground Sokoto Rock Phosphate and Morocco Rock Phosphate to enhance productivity of maize- (Zea mays L.) Sorghum (Sorghum bicolor) and soybean- (Glycine max L.) Sorghum crop rotation schemes was evaluated using Single Super Phosphate as reference fertilizer. The experiments were carried out in the screen house of the Department of Agronomy, University of Ibadan, in February and June 2013. The experiments involved 2 × 2 × 4 × 3 factorial in a Completely Randomized De...

  7. Mapping Cropping Practices of a Sugarcane-Based Cropping System in Kenya Using Remote Sensing

    Directory of Open Access Journals (Sweden)

    Betty Mulianga

    2015-10-01

    Full Text Available Over the recent past, there has been a growing concern on the need for mapping cropping practices in order to improve decision-making in the agricultural sector. We developed an original method for mapping cropping practices: crop type and harvest mode, in a sugarcane landscape of western Kenya using remote sensing data. At local scale, a temporal series of 15-m resolution Landsat 8 images was obtained for Kibos sugar management zone over 20 dates (April 2013 to March 2014 to characterize cropping practices. To map the crop type and harvest mode we used ground survey and factory data over 1280 fields, digitized field boundaries, and spectral indices (the Normalized Difference Vegetation Index (NDVI and the Normalized Difference Water Index (NDWI were computed for all Landsat images. The results showed NDVI classified crop type at 83.3% accuracy, while NDWI classified harvest mode at 90% accuracy. The crop map will inform better planning decisions for the sugar industry operations, while the harvest mode map will be used to plan for sensitizations forums on best management and environmental practices.

  8. Rotational mixing in massive binaries: detached short-period systems

    CERN Document Server

    de Mink, S E; Langer, N; Pols, O R; Brott, I; Yoon, S -Ch

    2009-01-01

    Models of rotating single stars can successfully account for a wide variety of observed stellar phenomena, such as the surface enhancements of N and He. However, recent observations have questioned the idea that rotational mixing is the main process responsible for the surface enhancements, emphasizing the need for a strong and conclusive test. We investigate the consequences of rotational mixing for massive main-sequence stars in short-period binaries. In these systems the tides spin up the stars to rapid rotation. We use a state-of-the-art stellar evolution code including the effect of rotational mixing, tides, and magnetic fields. We discuss the surface abundances expected in massive close binaries (M1~20 solar masses) and we propose using such systems to test the concept of rotational mixing. As these short-period binaries often show eclipses, their parameters can be determined with high accuracy, allowing for a direct comparison with binary evolution models. In more massive close systems (M1~50 solar mas...

  9. Effect of Cropping System and Contouring or Download Sowing on Soil Water Erosion under no Tillage

    Science.gov (United States)

    Marioti, J.; Padilha, J.; Bertol, I.; Barbosa, F. T.; Ramos, J. C.; Werner, R. S.; Vidal Vázquez, E.; Tanaka, M. S.

    2012-04-01

    Water erosion is the main responsible factor of soil and water losses, thus also causing soil degradation, especially on agricultural land, and it is also one factor of degradation outside the place of the origin of erosion. No tillage agriculture has been practiced in the last few decades for the purposes of water erosion control in various regions of Brazil. However, it has been shown that no tillage does not adequately control water erosion unless other complementary conservationist practices such as contour tillage or terracement. Although the erosion problem is widely recognized, there are still difficulties in estimating their magnitude, the environmental impact and the economic consequences, especially when it occurs in a conservation system like no tillage. The aim of this study was to quantify runoff and soil losses by water erosion under five different soil tillage treatments at Santa Catarina State, Southern Brazil. A field study was carried out using a rotating-boom rainfall simulator with 64 mmh-1 rainfall intensity for 90 minutes. Four rainfall tests were applied over the experimental period, one in each of the successive soybean and maize crop stages. Both soil cover by surface crop residue and soil cover by soybean and maize plant canopy were measured immediately before each rainfall test. Soil and water losses were smaller when sowing in contour than when sowing downslope. Contouring has promoted an average reduction of 42% in soil losses and 20% in water losses. Maize crop has promoted an average reduction of 19% in soil losses and 12% in water losses, in relation to the soybean crop. Therefore runoff rates and soil losses were higher in the downslope plots and in the soybean crop. Soil cover by previous crop residue was an important factor for reducing soil losses. Runoff rates were influenced by the soil water content before each rainfall test (R2= 0.78). The highest runoff occurred during the third simulated rainfall test, with the 83% of the

  10. Eco-efficient approaches to land management: a case for increased integration of crop and animal production systems.

    Science.gov (United States)

    Wilkins, R J

    2008-02-12

    Eco-efficiency is concerned with the efficient and sustainable use of resources in farm production and land management. It can be increased either by altering the management of individual crop and livestock enterprises or by altering the land-use system. This paper concentrates on the effects of crop sequence and rotation on soil fertility and nutrient use efficiency. The potential importance of mixed farming involving both crops and livestock is stressed, particularly when the systems incorporate biological nitrogen fixation and manure recycling. There is, however, little evidence that the trend in developed countries to farm-level specialization is being reduced. In some circumstances legislation to restrict diffuse pollution may provide incentives for more diverse eco-efficient farming and in other circumstances price premia for produce from eco-efficient systems, such as organic farming, and subsidies for the provision of environmental services may provide economic incentives for the adoption of such systems. However, change is likely to be most rapid where the present systems lead to obvious reductions in the productive potential of the land, such as in areas experiencing salinization. In other situations, there is promise that eco-efficiency could be increased on an area-wide basis by the establishment of linkages between farms of contrasting type, particularly between specialist crop and livestock farms, with contracts for the transfer of manures and, to a lesser extent, feeds.

  11. Soil properties, crop production and greenhouse gas emissions from organic and inorganic fertilizer-based arable cropping systems

    DEFF Research Database (Denmark)

    Chirinda, Ngonidzashe; Olesen, Jørgen Eivind; Porter, John Roy

    2010-01-01

    crops, respectively. Nevertheless, SOC levels in 2008 were similar across systems. The cumulative soil respiration for the period February to August 2008 ranged between 2 and 3 t CO2–C ha-1 and was correlated (r = 0.95) with average C inputs. In the organic cropping systems, pig slurry application......: total soil organic carbon (SOC), total N, microbial biomass N (MBN), potentially mineralizable N (PMN), and levels of potential ammonium oxidation (PAO) and denitrifying enzyme activity (DEA). In situ measurements of soil heterotrophic carbon dioxide (CO2) respiration and nitrous oxide emissions were...... and inclusion of catch crops generally increased soil respiration, PMN and PAO. At field capacity, relative gas diffusivity at 0–5 cm depth was >50% higher in the organic than the inorganic fertilizer-based system (P

  12. Exact treatment of interacting bosons in rotating systems and lattices

    DEFF Research Database (Denmark)

    Sørensen, Ole Søe

    Quantum systems of ultra-cold particles constitute a unique tool for studying the fundamental phenomena of physics in their purest and most isolated forms. Complicated dynamics are found even for few particles and to comprehend the features of systems with many particles, we must first understand...... mechanical nature of particles dominate, resulting in a behavior fundamentally different from that of classical particles. In rotating systems this causes quantization of angular momentum which can lead to macroscopic vortices in rotating Bose-Einstein condensates. In optical lattices the atom becomes...

  13. Comparing net ecosystem carbon dioxide exchange at adjacent commercial bioenergy and conventional cropping systems in Lincolnshire, United Kingdom

    Science.gov (United States)

    Morrison, Ross; Brooks, Milo; Evans, Jonathan; Finch, Jon; Rowe, Rebecca; Rylett, Daniel; McNamara, Niall

    2016-04-01

    The conversion of agricultural land to bioenergy plantations represents one option in the national and global effort to reduce greenhouse gas emissions whilst meeting future energy demand. Despite an increase in the area of (e.g. perennial) bioenergy crops in the United Kingdom and elsewhere, the biophysical and biogeochemical impacts of large scale conversion of arable and other land cover types to bioenergy cropping systems remain poorly characterised and uncertain. Here, the results of four years of eddy covariance (EC) flux measurements of net ecosystem CO2 exchange (NEE) obtained at a commercial farm in Lincolnshire, United Kingdom (UK) are reported. CO2 flux measurements are presented and compared for arable crops (winter wheat, oilseed rape, spring barely) and plantations of the perennial biofuel crops Miscanthus x. giganteus (C4) and short rotation coppice (SRC) willow (Salix sp.,C3). Ecosystem light and temperature response functions were used to analyse and compare temporal trends and spatial variations in NEE across the three land covers. All three crops were net in situ sinks for atmospheric CO2 but were characterised by large temporal and between site variability in NEE. Environmental and biological controls driving the spatial and temporal variations in CO2 exchange processes, as well as the influences of land management, will be analysed and discussed.

  14. An Ultrasonic System for Weed Detection in Cereal Crops

    Directory of Open Access Journals (Sweden)

    Dionisio Andújar

    2012-12-01

    Full Text Available Site-specific weed management requires sensing of the actual weed infestation levels in agricultural fields to adapt the management accordingly. However, sophisticated sensor systems are not yet in wider practical use, since they are not easily available for the farmers and their handling as well as the management practice requires additional efforts. A new sensor-based weed detection method is presented in this paper and its applicability to cereal crops is evaluated. An ultrasonic distance sensor for the determination of plant heights was used for weed detection. It was hypothesised that the weed infested zones have a higher amount of biomass than non-infested areas and that this can be determined by plant height measurements. Ultrasonic distance measurements were taken in a winter wheat field infested by grass weeds and broad-leaved weeds. A total of 80 and 40 circular-shaped samples of different weed densities and compositions were assessed at two different dates. The sensor was pointed directly to the ground for height determination. In the following, weeds were counted and then removed from the sample locations. Grass weeds and broad-leaved weeds were separately removed. Differences between weed infested and weed-free measurements were determined. Dry-matter of weeds and crop was assessed and evaluated together with the sensor measurements. RGB images were taken prior and after weed removal to determine the coverage percentages of weeds and crop per sampling point. Image processing steps included EGI (excess green index computation and thresholding to separate plants and background. The relationship between ultrasonic readings and the corresponding coverage of the crop and weeds were assessed using multiple regression analysis. Results revealed a height difference between infested and non-infested sample locations. Density and biomass of weeds present in the sample influenced the ultrasonic readings. The possibilities of weed group

  15. An ultrasonic system for weed detection in cereal crops.

    Science.gov (United States)

    Andújar, Dionisio; Weis, Martin; Gerhards, Roland

    2012-12-13

    Site-specific weed management requires sensing of the actual weed infestation levels in agricultural fields to adapt the management accordingly. However, sophisticated sensor systems are not yet in wider practical use, since they are not easily available for the farmers and their handling as well as the management practice requires additional efforts. A new sensor-based weed detection method is presented in this paper and its applicability to cereal crops is evaluated. An ultrasonic distance sensor for the determination of plant heights was used for weed detection. It was hypothesised that the weed infested zones have a higher amount of biomass than non-infested areas and that this can be determined by plant height measurements. Ultrasonic distance measurements were taken in a winter wheat field infested by grass weeds and broad-leaved weeds. A total of 80 and 40 circular-shaped samples of different weed densities and compositions were assessed at two different dates. The sensor was pointed directly to the ground for height determination. In the following, weeds were counted and then removed from the sample locations. Grass weeds and broad-leaved weeds were separately removed. Differences between weed infested and weed-free measurements were determined. Dry-matter of weeds and crop was assessed and evaluated together with the sensor measurements. RGB images were taken prior and after weed removal to determine the coverage percentages of weeds and crop per sampling point. Image processing steps included EGI (excess green index) computation and thresholding to separate plants and background. The relationship between ultrasonic readings and the corresponding coverage of the crop and weeds were assessed using multiple regression analysis. Results revealed a height difference between infested and non-infested sample locations. Density and biomass of weeds present in the sample influenced the ultrasonic readings. The possibilities of weed group discrimination were

  16. Climate change adaptability of cropping and farming systems for Europe

    DEFF Research Database (Denmark)

    Justes, Eric; Rossing, Walter; Vermue, Anthony

    Introduction: Prospective studies showed that the European agriculture will be impacted by climate change (CC) with different effects depending on the geographic region. The ERA-Net+ project Climate-CAFE (call of FACCE-JPI) aims to improve the “adaptive capacity” of arable and forage based farming...... systems to CC through a gradient of adaptation strategies. Methods: The adaptation strategies are evaluated at cropping and farming systems as well as regional levels for nine “Adaptation Pilots” along a North-South climate gradient in the EU. Three categories of strategies are evaluated: i) Resistance...... strategies that seek to maintain the status quo through management actions that reduce perturbations due to CC; ii) Resilience strategies requiring systemic adaptation at field and farm level for increasing the adaptive capacity after a climate disturbance; iii) Transformative strategies addressing needs...

  17. Performance of intact and castrated beef cattle in an intensive croppasture rotation system

    Directory of Open Access Journals (Sweden)

    Tercilio Turini

    2015-07-01

    Full Text Available This research had as objective to evaluate the performance of intact or castrated beef cattle in a croppasture rotation system. The experiment was conducted during 2004 and 2005, and carried out at the Cooperativa Agropecuária Mourãoense (COAMO Experimental Farm, in Campo Mourão city, Paraná state. It was used a completely randomized design, with two treatments, intact or castrated. Forty ½Angus+½Nelore crossbred animals, with average age of nine months, were used. Half of the animals were castrated at weaning, and the other half was kept intact. Pasture was composed of two areas. The winter field, established after soybean crop, was composed by a mixture of black oat (Avena strigosa and Italian ryegrass (Lolium multiforum. The summer field was composed by stargrass (Cynodon nlemfuensis and Mombaça grass (Panicum maximum. During the winter time it was used a continues grazing system, with regulator animals (put and take, and during the summer an intensive rotational system, with regulator animals and fixed grazing period. Intact animals presented higher average daily weight gain (0.907 vs 0.698 kg, slaughter weight (490.9 vs 442.2 kg, and hot carcass weight (250.2 vs 232.6 kg. Slaughter age was influenced by sexual condition, being lesser in the intact animals. Carcass dressing percentage was similar for the groups. Castrated animals showed better finishing fat cover and backfat thickness (3.45 vs 2.70 mm compared to intact ones. Therefore, it can be concluded that intact animals presents better performance than castrated ones when finished in an intensive crop-pasture rotation system, however, they may not present the minimum required fat cover, when slaughter at young ages.

  18. Development of a Vehicle-Mounted Crop Detection System

    Institute of Scientific and Technical Information of China (English)

    ZHONG Zhen-jiang; SUN Hong; LI Min-zan; ZHANG Feng; LI Xiu-hua

    2014-01-01

    In order to monitor plant chlorophyll content in real-time, a new vehicle-mounted detection system was developed to measure crop canopy spectral characteristics. It was designed to work as a wireless sensor network with one control unit and one measuring unit. The control unit included a personal digital assistant (PDA) device with a ZigBee wireless network coordinator. As the coordinator of the whole wireless network, the control unit was used to receive, display and store all the data sent from sensor nodes. The measuring unit consisted of several optical sensor nodes. All the sensor nodes were mounted on an on-board mechanical structure so that the measuring unit could collect the canopy spectral data while moving. Each sensor node contained four optical channels to measure the light radiation at the wavebands of 550, 650, 766, and 850 nm. The calibration tests veriifed a good performance in terms of the wireless transmission ability and the sensor measurement precision. Both stationary and moving ifeld experiments were also conducted in a winter wheat experimental ifeld. There was a high correlation between chlorophyll content and vegetation index, and several estimation models of the chlorophyll content were established. The highest R2 of the estimation models was 0.718. The results showed that the vehicle-mounted crop detection system has potential for ifeld application.

  19. Wireless computer vision system for crop stress detection

    Science.gov (United States)

    Knowledge of soil water deficits, crop water stress, and biotic stress from disease or insects is important for optimal irrigation scheduling and water management. Crop spectral reflectances provide a means to quantify visible and near infrared thermal crop stress, but in-situ measurements can be cu...

  20. Patient QA systems for rotational radiation therapy

    DEFF Research Database (Denmark)

    Fredh, Anna; Scherman, J.B.; Munck af Rosenschöld, Per Martin

    2013-01-01

    The purpose of the present study was to investigate the ability of commercial patient quality assurance (QA) systems to detect linear accelerator-related errors.......The purpose of the present study was to investigate the ability of commercial patient quality assurance (QA) systems to detect linear accelerator-related errors....

  1. Oscillating and rotating sine-Gordon system

    DEFF Research Database (Denmark)

    Olsen, O. H.; Samuelsen, Mogens Rugholm

    1986-01-01

    on the rate of change of the vacuum. For small rates a parametric excitation of standing waves is found, and for larger rates the system linearizes. In the case of oscillating vacuum a perturbation approach explains the behavior perfectly, while for small rates of increasing vacuum the system reduces...

  2. Rotational-resonance distance measurements in multi-spin systems.

    Science.gov (United States)

    Verhoeven, Aswin; Williamson, Philip T F; Zimmermann, Herbert; Ernst, Matthias; Meier, Beat H

    2004-06-01

    It is demonstrated that internuclear distances can be evaluated from rotational-resonance (RR) experiments in uniformly (13)C-labelled compounds. The errors in the obtained distances are less than 10% without the need to know any parameters of the spin system except the isotropic chemical shifts of all spins. We describe the multi-spin system with a simple fictitious spin-1/2 model. The influence of the couplings to the passive spins (J and dipolar coupling) is described by an empirical constant offset from the rotational-resonance condition. Using simulated data for a three-spin system, we show that the two-spin model describes the rotational-resonance transfer curves well as long as none of the passive spins is close to a rotational-resonance condition with one of the active spins. The usability of the two-spin model is demonstrated experimentally using a sample of acetylcholine perchlorate with labelling schemes of various levels of complexity. Doubly-, triply-, and fully labelled compounds lead to strongly varying RR polarization-transfer curves but the evaluated distances using the two-spin model are identical within the expected error limits and coincide with the distance from the X-ray structure. Rotational-resonance distance measurements in fully labelled compounds allow, in particular, the measurement of weak couplings in the presence of strong couplings.

  3. Environmental assessment of two different crop systems in terms of biomethane potential production.

    Science.gov (United States)

    Bacenetti, Jacopo; Fusi, Alessandra; Negri, Marco; Guidetti, Riccardo; Fiala, Marco

    2014-01-01

    The interest in renewable energy sources has gained great importance in Europe due to the need to reduce fossil energy consumption and greenhouse gas emissions, as required by the Renewable Energy Directive (RED) of the European Parliament. The production of energy from energy crops appears to be consistent with RED. The environmental impact related to this kind of energy primarily originates from crop cultivation. This research aimed to evaluate the environmental impact of different crop systems for biomass production: single and double crop. The environmental performances of maize and maize plus wheat were assessed from a life cycle perspective. Two alternative scenarios considering different yields, crop management, and climatic conditions, were also addressed. One normal cubic metre of potential methane was chosen as a functional unit. Methane potential production data were obtained through lab experimental tests. For both of the crop systems, the factors that have the greatest influence on the overall environmental burden are: fertilizer emissions, diesel fuel emissions, diesel fuel production, and pesticide production. Notwithstanding the greater level of methane potential production, the double crop system appears to have the worse environmental performance with respect to its single crop counterpart. This result is due to the bigger quantity of inputs needed for the double crop system. Therefore, the greater amount of biomass (silage) obtained through the double crop system is less than proportional to the environmental burden that results from the bigger quantity of inputs requested for double crop.

  4. Environmental assessment of two different crop systems in terms of biomethane potential production

    Energy Technology Data Exchange (ETDEWEB)

    Bacenetti, Jacopo; Fusi, Alessandra, E-mail: alessandra.fusi@unimi.it; Negri, Marco; Guidetti, Riccardo; Fiala, Marco

    2014-01-01

    The interest in renewable energy sources has gained great importance in Europe due to the need to reduce fossil energy consumption and greenhouse gas emissions, as required by the Renewable Energy Directive (RED) of the European Parliament. The production of energy from energy crops appears to be consistent with RED. The environmental impact related to this kind of energy primarily originates from crop cultivation. This research aimed to evaluate the environmental impact of different crop systems for biomass production: single and double crop. The environmental performances of maize and maize plus wheat were assessed from a life cycle perspective. Two alternative scenarios considering different yields, crop management, and climatic conditions, were also addressed. One normal cubic metre of potential methane was chosen as a functional unit. Methane potential production data were obtained through lab experimental tests. For both of the crop systems, the factors that have the greatest influence on the overall environmental burden are: fertilizer emissions, diesel fuel emissions, diesel fuel production, and pesticide production. Notwithstanding the greater level of methane potential production, the double crop system appears to have the worse environmental performance with respect to its single crop counterpart. This result is due to the bigger quantity of inputs needed for the double crop system. Therefore, the greater amount of biomass (silage) obtained through the double crop system is less than proportional to the environmental burden that results from the bigger quantity of inputs requested for double crop. - Highlights: • Environmental impact of two crop systems was evaluated • Biomethane specific production tests were carried out • Alternative scenarios (different yields and crop management) were assessed • Maize single crop obtains the better environmental performance • Critical factors are: fertilizer and diesel fuel emissions and diesel fuel

  5. Fibre optic system for monitoring rotational seismic phenomena.

    Science.gov (United States)

    Kurzych, Anna; Jaroszewicz, Leszek R; Krajewski, Zbigniew; Teisseyre, Krzysztof P; Kowalski, Jerzy K

    2014-03-19

    We outline the development and the application in a field test of the Autonomous Fibre-Optic Rotational Seismograph (AFORS), which utilizes the Sagnac effect for a direct measurement of the seismic-origin rotations of the ground. The main advantage of AFORS is its complete insensitivity to linear motions, as well as a direct measurement of rotational components emitted during seismic events. The presented system contains a special autonomous signal processing unit which optimizes its operation for the measurement of rotation motions, whereas the applied telemetric system based on the Internet allows for an AFORS remote control. The laboratory investigation of such two devices indicated that they keep an accuracy of no less than 5.1 × 10(-9) to 5.5 × 10(-8) rad/s in the detection frequency band from 0.83~106.15 Hz and protect linear changes of sensitivity in the above bandpass. Some experimental results of an AFORS-1 application for a continuous monitoring of the rotational events in the Książ (Poland) seismological observatory are also presented.

  6. Fibre Optic System for Monitoring Rotational Seismic Phenomena

    Directory of Open Access Journals (Sweden)

    Anna Kurzych

    2014-03-01

    Full Text Available We outline the development and the application in a field test of the Autonomous Fibre-Optic Rotational Seismograph (AFORS, which utilizes the Sagnac effect for a direct measurement of the seismic-origin rotations of the ground. The main advantage of AFORS is its complete insensitivity to linear motions, as well as a direct measurement of rotational components emitted during seismic events. The presented system contains a special autonomous signal processing unit which optimizes its operation for the measurement of rotation motions, whereas the applied telemetric system based on the Internet allows for an AFORS remote control. The laboratory investigation of such two devices indicated that they keep an accuracy of no less than 5.1 × 10−9 to 5.5 × 10−8 rad/s in the detection frequency band from 0.83~106.15 Hz and protect linear changes of sensitivity in the above bandpass. Some experimental results of an AFORS-1 application for a continuous monitoring of the rotational events in the Książ (Poland seismological observatory are also presented.

  7. Effects of uniform rotational flow on predator-prey system

    Science.gov (United States)

    Lee, Sang-Hee

    2012-12-01

    Rotational flow is often observed in lotic ecosystems, such as streams and rivers. For example, when an obstacle interrupts water flowing in a stream, energy dissipation and momentum transfer can result in the formation of rotational flow, or a vortex. In this study, I examined how rotational flow affects a predator-prey system by constructing a spatially explicit lattice model consisting of predators, prey, and plants. A predation relationship existed between the species. The species densities in the model were given as S (for predator), P (for prey), and G (for plant). A predator (prey) had a probability of giving birth to an offspring when it ate prey (plant). When a predator or prey was first introduced, or born, its health state was assigned an initial value of 20 that subsequently decreased by one with every time step. The predator (prey) was removed from the system when the health state decreased to less than zero. The degree of flow rotation was characterized by the variable, R. A higher R indicates a higher tendency that predators and prey move along circular paths. Plants were not affected by the flow because they were assumed to be attached to the streambed. Results showed that R positively affected both predator and prey survival, while its effect on plants was negligible. Flow rotation facilitated disturbances in individuals’ movements, which consequently strengthens the predator and prey relationship and prevents death from starvation. An increase in S accelerated the extinction of predators and prey.

  8. [Effects of conservation tillage on soil water conservation and crop yield of winter wheat-spring maize rotation field in Weibei highland].

    Science.gov (United States)

    Zhang, Li-hua; Li, Jun; Jia, Zhi-kuan; Liu, Bing-feng; Zhao, Hong-li; Shang, Jin-xia

    2011-07-01

    A field experiment was conducted in 2007-2010 to study the effects of no-tillage, subsoiling, and deep-ploughing combined with balanced fertilization, traditional fertilization, and no (or lower amount) fertilization on the soil water storage, crop yield, water use efficiency (WUE), and economic return of winter wheat-spring maize rotation field in Weibei highland. Among the tillage measures, no-tillage in fallow period had the best effect in soil water conservation, followed by sub-soiling, and deep-ploughing. The average water storage in 0-200 cm soil layer in crop growth period under no-tillage and sub-soiling was 6.7% and 1.9% higher than that under deep-ploughing, respectively. Under the balanced, traditional, and no (or lower amount) fertilizations, subsoiling all showed the highest yield, WUE, and economic return, with the best effect under balanced fertilization. The three-year crop yield under sub-soiling combined with balanced fertilization was 6909, 9689, and 5589 kg x hm(-2), WUE was 18.5, 25.2, and 23.0 kg x hm(-2) x mm(-1), and economic return was 5034, 5045, and 7098 yuan x hm(-2), respectively. It was suggested that balanced fertilization combined with sub-soiling had the best effect in soil water conservation and yield- and income increase, being the more appropriate fertilization and tillage mode for the wheat-maize rotation field in Weibei highland.

  9. Performance of spring barley varieties and variety mixtures as affected by manure application and their order in an organic crop rotation

    DEFF Research Database (Denmark)

    Askegaard, Margrethe; Thomsen, Ingrid Kaag; Berntsen, Jørgen

    2011-01-01

    In order to obtain a high and stable yield of organic spring barley, production should be optimized according to the specific environment. To test the performance of spring barley varieties under varying cropping conditions, a field experiment was carried out in 2003 and 2004 in a six-field mixed...... organic crop rotation. We investigated the choice of variety, the order in a rotation, and the application of manure (slurry and farmyard manure; 0 to 120 total-N ha−1) on grain yields of six selected varieties with different characteristics grown in either pure stands or in two spring barley mixtures......, each consisting of three varieties. Average grain yield of the barley varieties varied between 3.3 t DM ha−1 and 4.1 t DM ha−1. Grain yields of the two mixtures were 4.0 and 3.6 t DM ha−1, respectively. The varieties/mixtures interacted with crop order and year. Foliar diseases were more severe...

  10. Crop response of aerobic rice and winter wheat to nitrogen, phosphorus and potassium in a double cropping system

    OpenAIRE

    Dai, X.Q.; Zhang, H. Y.; Spiertz, J.H.J.; J. Yu; Xie, G.H.; Bouman, B.A.M.

    2010-01-01

    In the aerobic rice system, adapted rice cultivars are grown in non-flooded moist soil. Aerobic rice may be suitable for double cropping with winter wheat in the Huai River Basin, northern China plain. Field experiments in 2005 and 2006 were conducted to study the response of aerobic rice and winter wheat to sequential rates of nitrogen (N), phosphorus (P) and potassium (K) in aerobic rice—winter wheat (AR-WW) and winter wheat—aerobic rice (WW-AR) cropping sequences. Fertilizer treatments con...

  11. Using the GENESYS model quantifying the effect of cropping systems on gene escape from GM rape varieties to evaluate and design cropping systems

    Directory of Open Access Journals (Sweden)

    Colbach Nathalie

    2004-01-01

    Full Text Available Gene flow in rapeseed is a process taking place both in space and over the years and cannot be studied exclusively by field trials. Consequently, the GENESYS model was developed to quantify the effects of cropping systems on transgene escape from rapeseed crops to rapeseed volunteers in neighbour plots and in the subsequent crops. In the present work, this model was used to evaluate the risk of rape harvest contamination by extraneous genes in various farming systems in case of co-existing GM, conventional and organic crops. When 50 % of the rape varieties in the region were transgenic, the rate of GM seeds in non-GM crop harvests on farms with large fields was lower than the 0.9 % purity threshold proposed by the EC for rape crop production (food and feed harvests, but on farms with smaller fields, the threshold was exceeded. Harvest impurity increased in organic farms, mainly because of their small field size. The model was then used to evaluate the consequences of changes in farming practices and to identify those changes reducing harvest contamination. The effects of these changes depended on the field pattern and farming system. The most efficient practices in limiting harvest impurity comprised improved set-aside management by sowing a cover crop in spring on all set-aside fields in the region, permanently banning rape crops and set-aside around seed production fields and (for non-GM farmers clustering farm fields to reduce gene inflow from neighbour fields.

  12. Soil Fungal Resources in Annual Cropping Systems and Their Potential for Management

    Directory of Open Access Journals (Sweden)

    Walid Ellouze

    2014-01-01

    Full Text Available Soil fungi are a critical component of agroecosystems and provide ecological services that impact the production of food and bioproducts. Effective management of fungal resources is essential to optimize the productivity and sustainability of agricultural ecosystems. In this review, we (i highlight the functional groups of fungi that play key roles in agricultural ecosystems, (ii examine the influence of agronomic practices on these fungi, and (iii propose ways to improve the management and contribution of soil fungi to annual cropping systems. Many of these key soil fungal organisms (i.e., arbuscular mycorrhizal fungi and fungal root endophytes interact directly with plants and are determinants of the efficiency of agroecosystems. In turn, plants largely control rhizosphere fungi through the production of carbon and energy rich compounds and of bioactive phytochemicals, making them a powerful tool for the management of soil fungal diversity in agriculture. The use of crop rotations and selection of optimal plant genotypes can be used to improve soil biodiversity and promote beneficial soil fungi. In addition, other agronomic practices (e.g., no-till, microbial inoculants, and biochemical amendments can be used to enhance the effect of beneficial fungi and increase the health and productivity of cultivated soils.

  13. Cryogenic cooling with cryocooler on a rotating system.

    Science.gov (United States)

    Oguri, S; Choi, J; Kawai, M; Tajima, O

    2013-05-01

    We developed a system that continuously maintains a cryocooler for long periods on a rotating table. A cryostat that holds the cryocooler is set on the table. A compressor is located on the ground and supplies high-purity (>99.999%) and high-pressure (1.7 MPa) helium gas and electricity to the cryocooler. The operation of the cryocooler and other instruments requires the development of interface components between the ground and rotating table. A combination of access holes at the center of the table and two rotary joints allows simultaneous circulation of electricity and helium gas. The developed system provides two innovative functions under the rotating condition, cooling from room temperature and the maintenance of a cold condition for long periods. We have confirmed these abilities as well as temperature stability under a condition of continuous rotation at 20 rpm. The developed system can be applied in various fields, e.g., in tests of Lorentz invariance, searches for axion, radio astronomy, and cosmology, and application of radar systems. In particular, there is a plan to use this system for a radio telescope observing cosmic microwave background radiation.

  14. Cryogenic cooling with cryocooler on a rotating system

    Science.gov (United States)

    Oguri, S.; Choi, J.; Kawai, M.; Tajima, O.

    2013-05-01

    We developed a system that continuously maintains a cryocooler for long periods on a rotating table. A cryostat that holds the cryocooler is set on the table. A compressor is located on the ground and supplies high-purity (>99.999%) and high-pressure (1.7 MPa) helium gas and electricity to the cryocooler. The operation of the cryocooler and other instruments requires the development of interface components between the ground and rotating table. A combination of access holes at the center of the table and two rotary joints allows simultaneous circulation of electricity and helium gas. The developed system provides two innovative functions under the rotating condition, cooling from room temperature and the maintenance of a cold condition for long periods. We have confirmed these abilities as well as temperature stability under a condition of continuous rotation at 20 rpm. The developed system can be applied in various fields, e.g., in tests of Lorentz invariance, searches for axion, radio astronomy, and cosmology, and application of radar systems. In particular, there is a plan to use this system for a radio telescope observing cosmic microwave background radiation.

  15. Energy crops for biogas plants. Mecklenburg-Western Pomerania; Energiepflanzen fuer Biogasanlagen. Mecklenburg-Vorpommern

    Energy Technology Data Exchange (ETDEWEB)

    Aurbacher, J.; Bull, I.; Formowitz, B. (and others)

    2012-06-15

    For agriculturists in Mecklenburg-Western Pomerania (Federal Republic of Germany), the brochure under consideration provides recommendations on alternative crop rotation systems. With the help of these alternative cultivation systems, crop rotation with high yields in combination with high diversity, diversification and sustainability can be realized. Subsequently to the presentation of energy crops for the production of biogas, recommendations for the design of crop rotation are given. Other chapters of this booklet deal with ensilage and gas yields as well as the economics of energy crop cultivation.

  16. Energy crops for biogas plants. Baden-Wuerttemberg; Energiepflanzen fuer Biogasanlagen. Baden-Wuerttemberg

    Energy Technology Data Exchange (ETDEWEB)

    Butz, A.; Heiermann, M.; Herrmann, C. [and others

    2013-05-01

    For agriculturists in Baden-Wuerttemberg (Federal Republic of Germany), the brochure under consideration provides recommendations on alternative crop rotation systems. With the help of these alternative cultivation systems, crop rotation with high yields in combination with high diversity, diversification and sustainability can be realized. Subsequently to the presentation of energy crops for the production of biogas, recommendations for the design of crop rotation are given. Other chapters of this booklet deal with ensilage and gas yields as well as the economics of energy crop cultivation.

  17. Energy crops for biogas plants. Saxony-Anhalt; Energiepflanzen fuer Biogasanlagen. Sachsen-Anhalt

    Energy Technology Data Exchange (ETDEWEB)

    Boese, L.; Buttlar, C. von; Boettcher, K. (and others)

    2012-07-15

    For agriculturists in Saxony-Anhalt (Federal Republic of Germany), the brochure under consideration provides recommendations on alternative crop rotation systems. With the help of these alternative cultivation systems, crop rotation with high yields in combination with high diversity, diversification and sustainability can be realized. Subsequently to the presentation of energy crops for the production of biogas, recommendations for the design of crop rotation are given. Other chapters of this booklet deal with ensilage and gas yields as well as the economics of energy crop cultivation.

  18. Crop systems and plant roots can modify the soil water holding capacity

    Science.gov (United States)

    Doussan, Claude; Cousin, Isabelle; Berard, Annette; Chabbi, Abad; Legendre, Laurent; Czarnes, Sonia; Toussaint, Bruce; Ruy, Stéphane

    2015-04-01

    . Finally, in field condition, on a larger time scale, we investigated the effect of crop alternations on the Lusignan ACBB SOERE site. That site presents on the same soil type different crop alternation treatments: an old, continuous grassland, a 8-year continuous cereal rotation and an alternation of cereal/grassland (3-years cereals and 3 to 6 years grassland). Measurements of AWC in these different crop systems setting, 8 years after implementation of the SOERE, show that AWC was different in the cereal/grassland alternation compared to the continuous cereal or grassland cropping systems (~15-20% increase). If such alteration of AWC may seem modest, modeling (in the case of ACBB SOERE) shows that this increase in AWC would increase the cereal yield but also decrease the water drainage out of the root zone, and the possible associated loss of nitrate and pesticides. As a conclusion, in line with some other literature data, roots can influence soil hydric properties and this opens a way to use plants as "soil engineers" to modulate the properties of the root zone, and thus the components of water balance, to mitigate effects of drought on crops… However, how and how much plants will modify the hydric properties, a question which mixes physics, biology, microbiology, crop system settings, is still in infancy and needs further research.

  19. Increasing Crop Diversity Mitigates Weather Variations and Improves Yield Stability

    Science.gov (United States)

    Gaudin, Amélie C. M.; Tolhurst, Tor N.; Ker, Alan P.; Janovicek, Ken; Tortora, Cristina; Martin, Ralph C.; Deen, William

    2015-01-01

    Cropping sequence diversification provides a systems approach to reduce yield variations and improve resilience to multiple environmental stresses. Yield advantages of more diverse crop rotations and their synergistic effects with reduced tillage are well documented, but few studies have quantified the impact of these management practices on yields and their stability when soil moisture is limiting or in excess. Using yield and weather data obtained from a 31-year long term rotation and tillage trial in Ontario, we tested whether crop rotation diversity is associated with greater yield stability when abnormal weather conditions occur. We used parametric and non-parametric approaches to quantify the impact of rotation diversity (monocrop, 2-crops, 3-crops without or with one or two legume cover crops) and tillage (conventional or reduced tillage) on yield probabilities and the benefits of crop diversity under different soil moisture and temperature scenarios. Although the magnitude of rotation benefits varied with crops, weather patterns and tillage, yield stability significantly increased when corn and soybean were integrated into more diverse rotations. Introducing small grains into short corn-soybean rotation was enough to provide substantial benefits on long-term soybean yields and their stability while the effects on corn were mostly associated with the temporal niche provided by small grains for underseeded red clover or alfalfa. Crop diversification strategies increased the probability of harnessing favorable growing conditions while decreasing the risk of crop failure. In hot and dry years, diversification of corn-soybean rotations and reduced tillage increased yield by 7% and 22% for corn and soybean respectively. Given the additional advantages associated with cropping system diversification, such a strategy provides a more comprehensive approach to lowering yield variability and improving the resilience of cropping systems to multiple environmental

  20. Increasing crop diversity mitigates weather variations and improves yield stability.

    Directory of Open Access Journals (Sweden)

    Amélie C M Gaudin

    Full Text Available Cropping sequence diversification provides a systems approach to reduce yield variations and improve resilience to multiple environmental stresses. Yield advantages of more diverse crop rotations and their synergistic effects with reduced tillage are well documented, but few studies have quantified the impact of these management practices on yields and their stability when soil moisture is limiting or in excess. Using yield and weather data obtained from a 31-year long term rotation and tillage trial in Ontario, we tested whether crop rotation diversity is associated with greater yield stability when abnormal weather conditions occur. We used parametric and non-parametric approaches to quantify the impact of rotation diversity (monocrop, 2-crops, 3-crops without or with one or two legume cover crops and tillage (conventional or reduced tillage on yield probabilities and the benefits of crop diversity under different soil moisture and temperature scenarios. Although the magnitude of rotation benefits varied with crops, weather patterns and tillage, yield stability significantly increased when corn and soybean were integrated into more diverse rotations. Introducing small grains into short corn-soybean rotation was enough to provide substantial benefits on long-term soybean yields and their stability while the effects on corn were mostly associated with the temporal niche provided by small grains for underseeded red clover or alfalfa. Crop diversification strategies increased the probability of harnessing favorable growing conditions while decreasing the risk of crop failure. In hot and dry years, diversification of corn-soybean rotations and reduced tillage increased yield by 7% and 22% for corn and soybean respectively. Given the additional advantages associated with cropping system diversification, such a strategy provides a more comprehensive approach to lowering yield variability and improving the resilience of cropping systems to multiple

  1. Outcomes of a Rotational Dissection System in Gross Anatomy

    Science.gov (United States)

    Marshak, David W.; Oakes, Joanne; Hsieh, Pei-Hsuan; Chuang, Alice Z.; Cleary, Leonard J.

    2015-01-01

    At the University of Texas Houston Medical School, a rotational dissection system was introduced to improve coordination between the Gross Anatomy and the Introduction to Clinical Medicine (ICM) courses. Six students were assigned to each cadaver and divided into two teams. For each laboratory, one team was assigned to dissect and the other to…

  2. Population dynamics of plant nematodes in cultivated soil: effects of combinations of cropping systems and nematicides.

    Science.gov (United States)

    Murphy, W S; Brodie, B B; Good, J M

    1974-07-01

    The population density of Meloidogyne incognita was significantly reduced in land that was fallowed or cropped to crotalaria, marigold, bermudagrass, or bahiagrass. The rate of population decline caused by different cropping systems was influenced by initial population densities. Crotalaria, marigold, and bare fallow were about equally effective in reducing the density of M. incognita below dctectable lcvels, usually requiring 1-3 yr. Bahiagrass and bcrmudagrass required 4-5 yr or longer to reduce M. incognita below a detectable level. A high population density of Trichodorus christiei developed in land cropped 5 yr to bermudagrass, bahiagrass, okra, and marigold. Population densities of Pratylenchus brachyurus and Xiphinema americanum increased in land cropped to crotalaria or bermudagrass. Belonolabnus Iongicaudatus was detected only in land cropped to bermudagrass, The effectiveness of nematicides in reducing M. incognita infection was rclatcd to nematode population density resulting from 5 yr of different cropping systems. Treatment with aldicarb reduced M. incognita below detectable levels following all cropping systems; treatment with ethoprop following all cropping systems except okra, treatment wflh ethylene dibromide following bahiagrass or fallow; and treatment with DBCP only after 5 yr of fallow. Tomato transplant growth was affected .by both cropping systems and nematicide treatment. Transplants grown after crotalaria and bahiagrass were significantly larger than those grown after other crops. Also, treatment with aldicarb and ethoprop significantly increased transplant size.

  3. Resonant microsphere gyroscope based on a double Faraday rotator system.

    Science.gov (United States)

    Xie, Chengfeng; Tang, Jun; Cui, Danfeng; Wu, Dajin; Zhang, Chengfei; Li, Chunming; Zhen, Yongqiu; Xue, Chenyang; Liu, Jun

    2016-10-15

    The resonant microsphere gyroscope is proposed based on a double Faraday rotator system for the resonant microsphere gyroscope (RMSG) that is characterized by low insertion losses and does not destroy the reciprocity of the gyroscope system. Use of the echo suppression structure and the orthogonal polarization method can effectively inhibit both the backscattering noise and the polarization error, and reduce them below the system sensitivity limit. The resonance asymmetry rate dropped from 34.2% to 2.9% after optimization of the backscattering noise and the polarization noise, which greatly improved the bias stability and the scale factor linearity of the proposed system. Additionally, based on the optimum parameters for the double Faraday rotator system, a bias stability of 0.04°/s has been established for an integration time of 10 s in 1000 s in a resonator microsphere gyroscope using a microsphere resonator with a diameter of 1 mm and a Q of 7.2×106.

  4. Mixed crop-livestock systems: an economic and environmental-friendly way of farming?

    Science.gov (United States)

    Ryschawy, J; Choisis, N; Choisis, J P; Joannon, A; Gibon, A

    2012-10-01

    Intensification and specialisation of agriculture in developed countries enabled productivity to be improved but had detrimental impacts on the environment and threatened the economic viability of a huge number of farms. The combination of livestock and crops, which was very common in the past, is assumed to be a viable alternative to specialised livestock or cropping systems. Mixed crop-livestock systems can improve nutrient cycling while reducing chemical inputs and generate economies of scope at farm level. Most assumptions underlying these views are based on theoretical and experimental evidence. Very few assessments of their environmental and economic advantages have nevertheless been undertaken in real-world farming conditions. In this paper, we present a comparative assessment of the environmental and economic performances of mixed crop-livestock farms v. specialised farms among the farm population of the French 'Coteaux de Gascogne'. In this hilly region, half of the farms currently use a mixed crop-livestock system including beef cattle and cash crops, the remaining farms being specialised in either crops or cattle. Data were collected through an exhaustive survey of farms located in our study area. The economic performances of farming systems were assessed on 48 farms on the basis of (i) overall gross margin, (ii) production costs and (iii) analysis of the sensitivity of gross margins to fluctuations in the price of inputs and outputs. The environmental dimension was analysed through (i) characterisation of farmers' crop management practices, (ii) analysis of farm land use diversity and (iii) nitrogen farm-gate balance. Local mixed crop-livestock farms did not have significantly higher overall gross margins than specialised farms but were less sensitive than dairy and crop farms to fluctuations in the price of inputs and outputs considered. Mixed crop-livestock farms had lower costs than crop farms, while beef farms had the lowest costs as they are grass

  5. An overview of crop growing condition monitoring in China agriculture remote sensing monitoring system

    Science.gov (United States)

    Huang, Qing; Zhou, Qing-bo; Zhang, Li

    2009-07-01

    China is a large agricultural country. To understand the agricultural production condition timely and accurately is related to government decision-making, agricultural production management and the general public concern. China Agriculture Remote Sensing Monitoring System (CHARMS) can monitor crop acreage changes, crop growing condition, agriculture disaster (drought, floods, frost damage, pest etc.) and predict crop yield etc. quickly and timely. The basic principles, methods and regular operation of crop growing condition monitoring in CHARMS are introduced in detail in the paper. CHARMS can monitor crop growing condition of wheat, corn, cotton, soybean and paddy rice with MODIS data. An improved NDVI difference model was used in crop growing condition monitoring in CHARMS. Firstly, MODIS data of every day were received and processed, and the max NDVI values of every fifteen days of main crop were generated, then, in order to assessment a certain crop growing condition in certain period (every fifteen days, mostly), the system compare the remote sensing index data (NDVI) of a certain period with the data of the period in the history (last five year, mostly), the difference between NDVI can indicate the spatial difference of crop growing condition at a certain period. Moreover, Meteorological data of temperature, precipitation and sunshine etc. as well as the field investigation data of 200 network counties were used to modify the models parameters. Last, crop growing condition was assessment at four different scales of counties, provinces, main producing areas and nation and spatial distribution maps of crop growing condition were also created.

  6. Relationships among bulk soil physicochemical, biochemical, and microbiological parameters in an organic alfalfa-rice rotation system.

    Science.gov (United States)

    Lopes, Ana R; Bello, Diana; Prieto-Fernández, Ángeles; Trasar-Cepeda, Carmen; Manaia, Célia M; Nunes, Olga C

    2015-08-01

    The microbial communities of bulk soil of rice paddy fields under an ancient organic agriculture regimen, consisting on an alfalfa-rice rotation system, were characterized. The drained soil of two adjacent paddies at different stages of the rotation was compared before rice seeding and after harvesting. The relationships among the soil microbial, physicochemical, and biochemical parameters were investigated using multivariate analyses. In the first year of rice cropping, aerobic cultivable heterotrophic populations correlated with lineages of presumably aerobic bacteria (e.g., Sphingobacteriales, Sphingomonadales). In the second year of rice cropping, the total C content correlated with presumable anaerobic bacteria (e.g., Anaerolineae). Independently of the year of rice cropping, before rice seeding, proteolytic activity correlated positively with the cultivable aerobic heterotrophic and ammonifier populations, the soil catabolic profile and with presumable aerobes (e.g., Sphingobacteriales, Rhizobiales) and anaerobes (e.g., Bacteroidales, Anaerolineae). After harvesting, strongest correlations were observed between cultivable diazotrophic populations and bacterial groups described as comprising N2 fixing members (e.g., Chloroflexi-Ellin6529, Betaproteobacteria, Alphaproteobacteria). It was demonstrated that chemical parameters and microbial functions were correlated with variations on the total bacterial community composition and structure occurring during rice cropping. A better understanding of these correlations and of their implications on soil productivity may be valid contributors for sustainable agriculture practices, based on ancient processes.

  7. Cryogenic cooling with cryocooler on a rotating system

    CERN Document Server

    Oguri, Shugo; Kawai, Masanori; Tajima, Osamu

    2013-01-01

    We developed a system that continuously maintains a cryocooler for long periods on a rotating table. A cryostat that holds the cryocooler is set on the table. A compressor is located on the ground and supplies high-purity (> 99.999%) and high-pressure (1.7 MPa) helium gas and electricity to the cryocooler. The operation of the cryocooler and other instruments requires the development of interface components between the ground and rotating table. A combination of access holes at the center of the table and two rotary joints allows simultaneous circulation of electricity and helium gas. The developed system provides two innovative functions under the rotating condition; cooling from room temperature and the maintenance of a cold condition for long periods. We have confirmed these abilities as well as temperature stability under a condition of continuous rotation at 20 revolutions per minute. The developed system can be applied in various fields; e.g., in tests of Lorentz invariance, searches for axion, radio as...

  8. DayCent modelling of Swiss cropping systems

    Science.gov (United States)

    Necpalova, Magdalena; Lee, Juhwan; Büchi, Lucie; Mäder, Paul; Mayer, Jochen; Charles, Raphael; van der Heijden, Marcel; Six, Johan

    2016-04-01

    There is a growing need to identify and evaluate sustainable greenhouse gas (GHG) mitigation options, their bio-economic feasibility in the agricultural sector, and support implementation of agricultural GHG mitigation activities that are an integral part of climate change strategies. In recent years, several ecosystem biogeochemical process-based models and comprehensive decision making tools integrated with these models have been developed. The DayCent model simulates all major ecosystem processes that affect soil C and N dynamics, including plant production, water flow, heat transport, SOC decomposition, N mineralization and immobilization, nitrification, denitrification, and methane oxidation. However, if the model is to be reliably used for identification of GHG mitigation options and climate change strategies across the EU agricultural regions, it requires site- and region-specific calibration and evaluation. Here, we calibrated and validated the model to Swiss climate and soil conditions and management options using available long-term experimental data. Data on crop productivity, soil organic carbon and N2O emissions were derived from four field sites located in Thervil (1977-2013), Frick (2003-2013), Changins (1971-2013), and Reckenholz (2009-2013) that have evaluated the effects of agricultural input systems (specifically, organic, biodynamic, and conventional with and without manure additions) and soil management options (various tillage practices and cover cropping). The preliminary results show that the DayCent model was able to reproduce 76% of variability in the crop productivity (n = 1 316) and 75% variability in measured soil organic carbon (n = 402) across all long-term trials. Model calibration was evaluated against independent proportions of the data. The uncertainty in model predictions induced by model structure and uncertainty in the measured data still needs to be further evaluated using the Monte Carlo approach. The calibrated model will be

  9. The influence of nitrogen fertiliser rate and crop rotation on soil methane flux in rain-fed potato fields in Wuchuan County, China

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Liwei [College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China); College of Agronomy, Shenyang Agricultural University, Shenyang 110866 (China); Wuchuan Scientific Observing and Experimental Station of Agro-Environment, Ministry of Agriculture Wuchuan 011700 (China); Pan, Zhihua, E-mail: panzhihua@cau.edu.cn [College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China); Wuchuan Scientific Observing and Experimental Station of Agro-Environment, Ministry of Agriculture Wuchuan 011700 (China); Xu, Hui [Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016 (China); Wang, Cheng [College of Agricultural and Biotechnology, China Agricultural University, Beijing 100193 (China); Gao, Lin [School of Resources and Environmental, Anhui Agricultural University, Hefei 230036 (China); Zhao, Peiyi [Institute of Resources Environmental and Detection Technology, Inner Mongolia Academy of Agricultural and Animal Husbandry Sciences, Huhhot 010031 (China); Wuchuan Scientific Observing and Experimental Station of Agro-Environment, Ministry of Agriculture Wuchuan 011700 (China); Dong, Zhiqiang; Zhang, Jingting; Cui, Guohui; Wang, Sen; Han, Guolin; Zhao, Hui [College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China); Wuchuan Scientific Observing and Experimental Station of Agro-Environment, Ministry of Agriculture Wuchuan 011700 (China)

    2015-12-15

    As one of the important greenhouse gases, the characteristics and principles of methane exchange characteristics in cultivated lands have become hot topics in current climate change research. This study examines the influences of nitrogen fertilisation, temperature and soil water content on methane exchange characteristic and methane exchange functional gene-pmoA gene abundance based on experimental observations of methane exchange fluxes using the static chamber–gas chromatographic method and measurements of methanotroph gene copy numbers in three growing periods by real-time PCR in rain-fed potato fields. The results indicate that the rain-fed potato fields were a CH{sub 4} sink with an average annual methane absorption (negative emission) of 940.8 ± 103.2 g CH{sub 4}-C/ha/year. The cumulative methane absorption first exhibited flat and subsequently increasing trend with the increase of nitrogen fertilisation from 0 ~ 135 kg N·ha{sup −1}. Methane cumulative absorption significantly increased with the increase of temperature when temperatures were below 19.6 °C. Methane oxidation capacity (methanotroph pmoA gene copy numbers) showed an increasing and subsequently decreasing trend with the increase of soil moisture. Crop rotation was observed to increase the methane absorption in rain-fed potato fields and nearly one time higher than that under continuous cropping. A mechanism concept model of the methane exchange in rain-fed potato fields was advanced in this paper. - Highlights: • Rain-fed potato fields were a CH{sub 4} sink. • Increased nitrogen fertilisation and temperature led to higher CH{sub 4} absorption. • CH{sub 4} oxidation capacity showed a parabolic trend with soil moisture increased. • Crop rotation increased CH{sub 4} absorption one time higher than continuous cropping. • A mechanism concept model of the CH{sub 4} exchange in potato fields was advanced.

  10. Effects of nitrification inhibitors (DCD and DMPP on nitrous oxide emission, crop yield and nitrogen uptake in a wheat–maize cropping system

    Directory of Open Access Journals (Sweden)

    C. Liu

    2013-04-01

    Full Text Available The application of nitrification inhibitors together with ammonium-based fertilizers is proposed as a potent method to decrease nitrous oxide (N2O emission while promoting crop yield and nitrogen use efficiency in fertilized agricultural fields. To evaluate the effects of nitrification inhibitors, we conducted year-round measurements of N2O fluxes, yield, aboveground biomass, plant carbon and nitrogen contents, soil inorganic nitrogen and dissolved organic carbon contents and the main environmental factors for urea (U, urea + dicyandiamide (DCD and urea + 3,4-dimethylpyrazol phosphate (DMPP treatments in a wheat–maize rotation field. The cumulative N2O emissions were calculated to be 4.49 ± 0.21, 2.93 ± 0.06 and 2.78 ± 0.16 kg N ha−1 yr−1 for the U, DCD and DMPP treatments, respectively. Therefore, the DCD and DMPP treatments significantly decreased the annual emissions by 35% and 38%, respectively (p 2O emissions. When the emissions presented clearly temporal variations, high-frequency measurements or optimized sampling schedule for intermittent measurements would likely provide more accurate estimations of annual cumulative emission and treatment effect. The application of nitrification inhibitors significantly increased the soil inorganic nitrogen content (p 2O emission from the wheat–maize cropping system.

  11. Effects of nitrification inhibitors (DCD and DMPP) on nitrous oxide emission, crop yield and nitrogen uptake in a wheat-maize cropping system

    Science.gov (United States)

    Liu, C.; Wang, K.; Zheng, X.

    2013-04-01

    The application of nitrification inhibitors together with ammonium-based fertilizers is proposed as a potent method to decrease nitrous oxide (N2O) emission while promoting crop yield and nitrogen use efficiency in fertilized agricultural fields. To evaluate the effects of nitrification inhibitors, we conducted year-round measurements of N2O fluxes, yield, aboveground biomass, plant carbon and nitrogen contents, soil inorganic nitrogen and dissolved organic carbon contents and the main environmental factors for urea (U), urea + dicyandiamide (DCD) and urea + 3,4-dimethylpyrazol phosphate (DMPP) treatments in a wheat-maize rotation field. The cumulative N2O emissions were calculated to be 4.49 ± 0.21, 2.93 ± 0.06 and 2.78 ± 0.16 kg N ha-1 yr-1 for the U, DCD and DMPP treatments, respectively. Therefore, the DCD and DMPP treatments significantly decreased the annual emissions by 35% and 38%, respectively (p regulated the seasonal fluctuation of N2O emissions. When the emissions presented clearly temporal variations, high-frequency measurements or optimized sampling schedule for intermittent measurements would likely provide more accurate estimations of annual cumulative emission and treatment effect. The application of nitrification inhibitors significantly increased the soil inorganic nitrogen content (p emission from the wheat-maize cropping system.

  12. Maximum soil organic carbon storage in Midwest U.S. cropping systems when crops are optimally nitrogen-fertilized

    Science.gov (United States)

    Barker, Daniel W.; Helmers, Matthew J.; Miguez, Fernando E.; Olk, Daniel C.; Sawyer, John E.; Six, Johan; Castellano, Michael J.

    2017-01-01

    Nitrogen fertilization is critical to optimize short-term crop yield, but its long-term effect on soil organic C (SOC) is uncertain. Here, we clarify the impact of N fertilization on SOC in typical maize-based (Zea mays L.) Midwest U.S. cropping systems by accounting for site-to-site variability in maize yield response to N fertilization. Within continuous maize and maize-soybean [Glycine max (L.) Merr.] systems at four Iowa locations, we evaluated changes in surface SOC over 14 to 16 years across a range of N fertilizer rates empirically determined to be insufficient, optimum, or excessive for maximum maize yield. Soil organic C balances were negative where no N was applied but neutral (maize-soybean) or positive (continuous maize) at the agronomic optimum N rate (AONR). For continuous maize, the rate of SOC storage increased with increasing N rate, reaching a maximum at the AONR and decreasing above the AONR. Greater SOC storage in the optimally fertilized continuous maize system than in the optimally fertilized maize-soybean system was attributed to greater crop residue production and greater SOC storage efficiency in the continuous maize system. Mean annual crop residue production at the AONR was 22% greater in the continuous maize system than in the maize-soybean system and the rate of SOC storage per unit residue C input was 58% greater in the monocrop system. Our results demonstrate that agronomic optimum N fertilization is critical to maintain or increase SOC of Midwest U.S. cropland. PMID:28249014

  13. Long-Term Effects of Rotational Tillage On Visual Evaluation of Soil Structure, Soil Quality and Crop Yield

    DEFF Research Database (Denmark)

    Munkholm, Lars Juhl; Heck, Richard; Deen, Bill

    year old long-term rotation and tillage treatment experiment on a Canadian silt loam soil. Measurements were carried out in the topsoil for three different rotations: R1 (C-C-C-C) continuous corn (Zea mays L.), R6. (C-C-O(RC), B(RC)) corn, corn, oats (Avena fatua L.) and spring barley (Hordeum vulgare...

  14. Intellectualized Identifying and Precision Control System for Horticultural Crop Diseases Based on Small Unmanned Aerial Vehicle

    OpenAIRE

    Cao, Hongxin; Yang, Yuwang; Pei, Zhiyuan; Zhang, Wenyu; Ge, Daokuo; Sha, Yiran; Zhang, Weixin; Fu, Kunya; Liu, Yan; Chen, Yuli; Dai, Hongjun; Zhang, Hainan

    2012-01-01

    International audience; To explore small unmanned aerial vehicle (UAV) remote sensing identifying technology for horticultural crop diseases, and to combine it with small UAV spraying, the peach leaf blade was taken as material, the peach shot-hole disease was taken as object for spectral capture, and the intellectualized identifying and precision control system for horticultural crop diseases were developed, mainly including the identifying system for horticultural crop diseases, spraying pe...

  15. Influence of Crop Management and Environmental Factors on Wolf Spider Assemblages (Araneae: Lycosidae) in an Australian Cotton Cropping System.

    Science.gov (United States)

    Rendon, Dalila; Whitehouse, Mary E A; Hulugalle, Nilantha R; Taylor, Phillip W

    2015-02-01

    Wolf spiders (Lycosidae) are the most abundant ground-hunting spiders in the Australian cotton (Gossypium hirsutum L.) agroecosystems. These spiders have potential in controlling pest bollworms, Helicoverpa spp. (Lepidoptera: Noctuidae) in minimum-tilled fields. A study was carried out during a wet growing season (2011-2012) in Narrabri, New South Wales, Australia, to determine how different crop rotations and tillage affect wolf spider assemblages in cotton fields. Spider abundance and species richness did not differ significantly between simple plots (no winter crop) and complex plots (cotton-wheat Triticum aestivum L.-vetch Vicia benghalensis L. rotation). However, the wolf spider biodiversity, as expressed by the Shannon-Weaver and Simpson's indices, was significantly higher in complex plots. Higher biodiversity reflected a more even distribution of the most dominant species (Venatrix konei Berland, Hogna crispipes Koch, and Tasmanicosa leuckartii Thorell) and the presence of more rare species in complex plots. T. leuckartii was more abundant in complex plots and appears to be sensitive to farming disturbances, whereas V. konei and H. crispipes were similarly abundant in the two plot types, suggesting higher resilience or recolonizing abilities. The demographic structure of these three species varied through the season, but not between plot types. Environmental variables had a significant effect on spider assemblage, but effects of environment and plot treatment were overshadowed by the seasonal progression of cotton stages. Maintaining a high density and even distribution of wolf spiders that prey on Helicoverpa spp. should be considered as a conservation biological control element when implementing agronomic and pest management strategies.

  16. Field-scale experiments reveal persistent yield gaps in low-input and organic cropping systems

    Science.gov (United States)

    Kravchenko, Alexandra N.; Snapp, Sieglinde S.; Robertson, G. Philip

    2017-01-01

    Knowledge of production-system performance is largely based on observations at the experimental plot scale. Although yield gaps between plot-scale and field-scale research are widely acknowledged, their extent and persistence have not been experimentally examined in a systematic manner. At a site in southwest Michigan, we conducted a 6-y experiment to test the accuracy with which plot-scale crop-yield results can inform field-scale conclusions. We compared conventional versus alternative, that is, reduced-input and biologically based–organic, management practices for a corn–soybean–wheat rotation in a randomized complete block-design experiment, using 27 commercial-size agricultural fields. Nearby plot-scale experiments (0.02-ha to 1.0-ha plots) provided a comparison of plot versus field performance. We found that plot-scale yields well matched field-scale yields for conventional management but not for alternative systems. For all three crops, at the plot scale, reduced-input and conventional managements produced similar yields; at the field scale, reduced-input yields were lower than conventional. For soybeans at the plot scale, biological and conventional managements produced similar yields; at the field scale, biological yielded less than conventional. For corn, biological management produced lower yields than conventional in both plot- and field-scale experiments. Wheat yields appeared to be less affected by the experimental scale than corn and soybean. Conventional management was more resilient to field-scale challenges than alternative practices, which were more dependent on timely management interventions; in particular, mechanical weed control. Results underscore the need for much wider adoption of field-scale experimentation when assessing new technologies and production-system performance, especially as related to closing yield gaps in organic farming and in low-resourced systems typical of much of the developing world. PMID:28096409

  17. Nitrous oxide and methane emissions from optimized and alternative cereal cropping systems on the North China Plain: A two-year field study

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Bing [College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China); Ju, Xiaotang, E-mail: juxt@cau.edu.cn [College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China); Su, Fang; Meng, Qingfeng [College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China); Oenema, Oene [Wageningen University and Research, Alterra, Wageningen (Netherlands); Christie, Peter [College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China); Agri-Environment Branch, Agri-Food and Biosciences Institute, Belfast BT9 5PX (United Kingdom); Chen, Xinping; Zhang, Fusuo [College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China)

    2014-02-01

    The impacts of different crop rotation systems with their corresponding management practices on grain yield, greenhouse gas emissions, and fertilizer nitrogen (N) and irrigation water use efficiencies are not well documented. This holds especially for the North China Plain which provides the staple food for hundreds of millions of people and where groundwater resources are polluted with nitrate and depleted through irrigation. Here, we report on fertilizer N and irrigation water use, grain yields, and nitrous oxide (N{sub 2}O) and methane (CH{sub 4}) emissions of conventional and optimized winter wheat–summer maize double-cropping systems, and of three alternative cropping systems, namely a winter wheat–summer maize (or soybean)–spring maize system, with three harvests in two years; and a single spring maize system with one crop per year. The results of this two-year study show that the optimized double-cropping system led to a significant increase in grain yields and a significant decrease in fertilizer N use and net greenhouse gas intensity, but the net greenhouse gas N{sub 2}O emissions plus CH{sub 4} uptake and the use of irrigation water did not decrease relative to the conventional system. Compared to the conventional system the net greenhouse gas emissions, net greenhouse gas intensity and use of fertilizer N and irrigation water decreased in the three alternative cropping systems, but at the cost of grain yields except in the winter wheat–summer maize–spring maize system. Net uptake of CH{sub 4} by the soil was little affected by cropping system. Average N{sub 2}O emission factors were only 0.17% for winter wheat and 0.53% for maize. In conclusion, the winter wheat–summer maize–spring maize system has considerable potential to decrease water and N use and decrease N{sub 2}O emissions while maintaining high grain yields and sustainable use of groundwater. - Highlights: • Yields, resource use efficiency and N{sub 2}O + CH{sub 4} emission

  18. Translational and rotational dynamic analysis of a superconducting levitation system

    Science.gov (United States)

    Cansiz, A.; Hull, J. R.; Gundogdu, Ö.

    2005-07-01

    The rotational dynamics of a disc-shaped permanent magnet rotor levitated over a high temperature superconductor was studied experimentally and theoretically. The interaction between the rotor magnet and the superconductor was modelled by assuming the magnet to be a magnetic dipole and the superconductor a diamagnet. In the magnetomechanical analysis of the superconductor part, the frozen image concept was combined with the diamagnetic image, and the damping in the system was neglected. The interaction potential of the system is the combination of magnetic and gravitational potentials. From the dynamical analysis the equations of motion of the permanent magnet were stated as a function of lateral, vertical, tilt, precision and rotating angles. The vibration behaviour and correlation of the vibration of one direction with that of another were determined with a numerical calculation based on the Runge-Kutta method. The various vibrational frequencies identified were vertical, radial, tilt, precession and rotation. The tests performed for experimental verifications were translational and rotational. The permanent magnet was 'spun up' under vacuum conditions to analyse the dynamics of the free 'spin down' behaviour of the permanent magnet.

  19. Spatial variability of soil total and DTPA-extractable cadmium caused by long-term application of phosphate fertilizers, crop rotation, and soil characteristics.

    Science.gov (United States)

    Jafarnejadi, A R; Sayyad, Gh; Homaee, M; Davamei, A H

    2013-05-01

    Increasing cadmium (Cd) accumulation in agricultural soils is undesirable due to its hazardous influences on human health. Thus, having more information on spatial variability of Cd and factors effective to increase its content on the cultivated soils is very important. Phosphate fertilizers are main contamination source of cadmium (Cd) in cultivated soils. Also, crop rotation is a critical management practice which can alter soil Cd content. This study was conducted to evaluate the effects of long-term consumption of the phosphate fertilizers, crop rotations, and soil characteristics on spatial variability of two soil Cd species (i.e., total and diethylene triamine pentaacetic acid (DTPA) extractable) in agricultural soils. The study was conducted in wheat farms of Khuzestan Province, Iran. Long-term (27-year period (1980 to 2006)) data including the rate and the type of phosphate fertilizers application, the respective area, and the rotation type of different regions were used. Afterwards, soil Cd content (total or DTPA extractable) and its spatial variability in study area (400,000 ha) were determined by sampling from soils of 255 fields. The results showed that the consumption rate of di-ammonium phosphate fertilizer have been varied enormously in the period study. The application rate of phosphorus fertilizers was very high in some subregions with have extensive agricultural activities (more than 95 kg/ha). The average and maximum contents of total Cd in the study region were obtained as 1.47 and 2.19 mg/kg and DTPA-extractable Cd as 0.084 and 0.35 mg/kg, respectively. The spatial variability of Cd indicated that total and DTPA-extractable Cd contents were over 0.8 and 0.1 mg/kg in 95 and 25 % of samples, respectively. The spherical model enjoys the best fitting and lowest error rate to appraise the Cd content. Comparing the phosphate fertilizer consumption rate with spatial variability of the soil cadmium (both total and DTPA extractable) revealed the high

  20. Influence of Soil Management on Water Retention from Saturation to Oven Dryness and Dominant Soil Water States in a Vertisol under Crop Rotation

    Science.gov (United States)

    Vanderlinden, Karl; Pachepsky, Yakov; Pederera, Aura; Martinez, Gonzalo; Espejo, Antonio Jesus; Giraldez, Juan Vicente

    2014-05-01

    Unique water transfer and retention properties of Vertisols strongly affect their use in rainfed agriculture in water-limited environments. Despite the agricultural importance of the hydraulic properties of those soils, water retention data dryer than the wilting point are generally scarce, mainly as a result of practical constraints of traditional water retention measurement methods. In this work we provide a detailed description of regionalized water retention data from saturation to oven dryness, obtained from 54 minimally disturbed topsoil (0-0.05m) samples collected at a 3.5-ha experimental field in SW Spain where conventional tillage (CT) and direct drilling (DD) is compared in a wheat-sunflower-legume crop rotation on a Vertisol. Water retention was measured from saturation to oven dryness using sand and sand-kaolin boxes, a pressure plate apparatus and a dew point psychrometer, respectively. A common shape of the water retention curve (WRC) was observed in both tillage systems, with a strong discontinuity in its slope near -0.4 MPa and a decreasing spread from the wet to the dry end. A continuous function, consisting of the sum of a double exponential model (Dexter et al, 2008) and the Groenevelt and Grant (2004) model could be fitted successfully to the data. Two inflection points in the WRC were interpreted as boundaries between the structural and the textural pore spaces and between the textural and the intra-clay aggregate pore spaces. Water retention was significantly higher in DD (pdry water content states. References Dexter, A.R., E.A. Czyż, G. Richard, A. Reszkowska, 2008. A user-friendly water retention function that takes account of the textural and structural pore spaces in soil. Geoderma, 143:243-253. Groenevelt, P.A., C.D. Grant, 2004. A new model for the soil-water retention curve that solves the problem of residual water contents. Eur. J. Soil Sci. 55:479-485.

  1. Emergy Assessment of a Wheat-Maize Rotation System with Different Water Assignments in the North China Plain

    Science.gov (United States)

    Hu, Shi; Mo, Xingguo; Lin, Zhonghui; Qiu, Jianxiu

    2010-10-01

    Sustainable water use is seriously compromised in the North China Plain (NCP) due to the huge water requirements of agriculture, the largest use of water resources. An integrated approach which combines the ecosystem model with emergy analysis is presented to determine the optimum quantity of irrigation for sustainable development in irrigated cropping systems. Since the traditional emergy method pays little attention to the dynamic interaction among components of the ecological system and dynamic emergy accounting is in its infancy, it is hard to evaluate the cropping system in hypothetical situations or in response to specific changes. In order to solve this problem, an ecosystem model (Vegetation Interface Processes (VIP) model) is introduced for emergy analysis to describe the production processes. Some raw data, collected by investigating or observing in conventional emergy analysis, may be calculated by the VIP model in the new approach. To demonstrate the advantage of this new approach, we use it to assess the wheat-maize rotation cropping system at different irrigation levels and derive the optimum quantity of irrigation according to the index of ecosystem sustainable development in NCP. The results show, the optimum quantity of irrigation in this region should be 240-330 mm per year in the wheat system and no irrigation in the maize system, because with this quantity of irrigation the rotation crop system reveals: best efficiency in energy transformation (transformity = 6.05E + 4 sej/J); highest sustainability (renewability = 25%); lowest environmental impact (environmental loading ratio = 3.5) and the greatest sustainability index (Emergy Sustainability Index = 0.47) compared with the system in other irrigation amounts. This study demonstrates that application of the new approach is broader than the conventional emergy analysis and the new approach is helpful in optimizing resources allocation, resource-savings and maintaining agricultural sustainability.

  2. Estabilidade de agregados do solo após manejo com rotações de culturas e escarificação Soil aggregate stability after management with crop rotation and chiseling

    Directory of Open Access Journals (Sweden)

    Juliano Carlos Calonego

    2008-08-01

    Full Text Available O objetivo desse trabalho foi avaliar, em solo compactado, a estabilidade dos agregados influenciada pelo cultivo de espécies de cobertura em esquema de rotações de culturas, em sistema de semeadura direta, mediante o efeito da escarificação mecânica. As rotações de culturas repetidas por três anos consecutivos envolveram o cultivo de triticale e girassol, no outono-inverno, associados ao cultivo de milheto, de sorgo forrageiro e de Crotalária júncea como plantas de cobertura, antecedendo o da soja (cultura de verão. No tratamento envolvendo a escarificação mecânica, a área permaneceu em pousio entre os cultivos de outono-inverno e de verão. O experimento foi realizado na Fazenda Experimental Lageado (Botucatu-SP, nos anos agrícolas de 2003/2004, 2004/2005 e 2005/2006. O delineamento experimental foi o de blocos ao acaso, com quatro repetições, em esquema de parcelas subdivididas. As amostras para a análise da estabilidade de agregados foram coletadas nas profundidades de 0 a 0,05 m e de 0,05 a 0,10 m após o manejo das plantas de cobertura em dezembro de 2003 e de 2005. Logo no primeiro ano de instalação do experimento, o cultivo de triticale resultou em maior porcentagem de agregados com mais de 2 mm, maior DMG e maior DMP na camada de 0 a 5 cm, além de maior DMP na camada de 0,05 a 0,10 m. Já a escarificação do solo e a ausência do cultivo de plantas de cobertura proporcionaram menor porcentagem de agregados maiores que 2 mm e menor DMP na camada de 0,05 a 0,10 m. A estabilidade dos agregados foi influenciada pela rotação de culturas, sendo maior na camada de 0 a 0,05 m e de 0,05 a 0,10 m quando o triticale foi introduzido como espécie de outono-inverno.The objective of this study was to compare, in compacted soil condition, the aggregate stability after different crops rotations under no-tillage system and chiseling. The following crop rotations were repeated for three consecutive years under no

  3. A quality assessment of the MARS crop yield forecasting system for the European Union

    Science.gov (United States)

    van der Velde, Marijn; Bareuth, Bettina

    2015-04-01

    Timely information on crop production forecasts can become of increasing importance as commodity markets are more and more interconnected. Impacts across large crop production areas due to (e.g.) extreme weather and pest outbreaks can create ripple effects that may affect food prices and availability elsewhere. The MARS Unit (Monitoring Agricultural ResourceS), DG Joint Research Centre, European Commission, has been providing forecasts of European crop production levels since 1993. The operational crop production forecasting is carried out with the MARS Crop Yield Forecasting System (M-CYFS). The M-CYFS is used to monitor crop growth development, evaluate short-term effects of anomalous meteorological events, and provide monthly forecasts of crop yield at national and European Union level. The crop production forecasts are published in the so-called MARS bulletins. Forecasting crop yield over large areas in the operational context requires quality benchmarks. Here we present an analysis of the accuracy and skill of past crop yield forecasts of the main crops (e.g. soft wheat, grain maize), throughout the growing season, and specifically for the final forecast before harvest. Two simple benchmarks to assess the skill of the forecasts were defined as comparing the forecasts to 1) a forecast equal to the average yield and 2) a forecast using a linear trend established through the crop yield time-series. These reveal a variability in performance as a function of crop and Member State. In terms of production, the yield forecasts of 67% of the EU-28 soft wheat production and 80% of the EU-28 maize production have been forecast superior to both benchmarks during the 1993-2013 period. In a changing and increasingly variable climate crop yield forecasts can become increasingly valuable - provided they are used wisely. We end our presentation by discussing research activities that could contribute to this goal.

  4. The effect of nitrogen fertilization and cover cropping systems on sorghum grain characteristics

    Science.gov (United States)

    The practice of no-till farming has become an increasingly popular cropping system, due to increased water and soil conservation. Recently, cover cropping has been added to the system to aid in weed prevention and also increase soil fertility. The objective of this study was to determine the effect ...

  5. A low-cost microcontroller-based system to monitor crop temperature and water status

    Science.gov (United States)

    A prototype microcontroller-based system was developed to automate the measurement and recording of soil-moisture status and canopy-, air-, and soil-temperature levels in cropped fields. Measurements of these conditions within the cropping system are often used to assess plant stress, and can assis...

  6. Evaluation of Learning Group Approaches for Fostering Integrated Cropping Systems Management

    Science.gov (United States)

    Blissett, Hana; Simmons, Steve; Jordan, Nicholas; Nelson, Kristen

    2004-01-01

    Cropping systems management requires integration of multiple forms of knowledge, practice, and learning by farmers, extension educators, and researchers. We evaluated the outcomes of participation in collaborative learning groups organized to address cropping systems and, specifically, challenges of integrated weed management. Groups were…

  7. Rice in cropping systems - Modelling transitions between flooded and non-flooded soil environments

    NARCIS (Netherlands)

    Gaydon, D.S.; Probert, M.E.; Buresh, R.J.; Meinke, H.B.; Suriadi, A.; Dobermann, A.; Bouman, B.A.M.; Timsina, J.

    2012-01-01

    Water shortages in many rice-growing regions, combined with growing global imperatives to increase food production, are driving research into increased water use efficiency and modified agricultural practices in rice-based cropping systems. Well-tested cropping systems models that capture interactio

  8. Produção de gado de corte e acúmulo de matéria seca em sistema de integração lavoura-pecuária em presença e ausência de trevo branco e nitrogênio Beef cattle production and dry matter accumulation in the crop-pasture rotation system in presence and absence of white clover and nitrogen

    Directory of Open Access Journals (Sweden)

    Alceu Luiz Assmann

    2004-02-01

    Full Text Available O trabalho foi conduzido com o objetivo de verificar a influência da adubação nitrogenada em uma pastagem de azevém (Lolium multiflorium L. e aveia (Avena strigosa Scherb em presença e ausência de trevo branco (Trifolium repens L., conferida pelo acúmulo e produção de matéria seca, ganho médio diário, ganho de peso vivo e carga animal no sistema de integração lavoura-pecuária sob sistema de plantio direto. A cultura antecessora da pastagem foi a soja (Glycine Max L.. O delineamento experimental foi em blocos completos ao acaso, com parcelas subdivididas e três repetições. Nas parcelas, foram testadas quatro doses de nitrogênio (0, 100, 200 e 300 kg.ha-1 e nas subparcelas, a combinação de presença e ausência de trevo branco. A elevação das doses crescentes de N aumentaram de forma linear crescente o acúmulo e a produção de matéria seca da pastagem. A carga animal e o ganho de peso vivo por hectare de bovinos aumentaram com o incremento de nitrogênio. Os resultados demonstram o efeito da adubação nitrogenada no acúmulo diário, na produção de matéria seca, carga animal e no ganho de peso vivo.The research was carried out to verify the influence of the nitrogen input in an Italian ryegrass (Lolium multiflorium L. and oat (Avena strigosa Scherb pasture, in presence and absence of white clover (Trifolium repens L., checked by the dry matter accumulation, dry matter yield, average daily gain, liveweight gain and stocking rate a crop-pasture rotation system, on no tillage system. Soybean (Glycine Max L. was cultivated before the grass. The experimental design was complete randomized blocks with split-plot model and three replications. In the plots, four nitrogen levels were tested (0, 100, 200 and 300 kg.ha-1 and in the split-plot model, the presence and absence of white clover. Increasing nitrogen levels increased in a cresecent linear way the dry matter accumulation and dry matter yield. The stocking rate and

  9. Rotation, magnetism, and metallicity of M dwarf systems

    CERN Document Server

    Shulyak, D; Reiners, A; Kochukhov, O; Piskunov, N

    2011-01-01

    Close M-dwarf binaries and higher multiples allow the investigation of rotational evolution and mean magnetic flux unbiased from scatter in inclination angle and age since the orientation of the spin axis of the components is most likely parallel and the individual systems are coeval. Systems composed of an early (M0.0 -- M4.0) and a late (M4.0 -- M8.0) type component offer the possibility to study differences in rotation and magnetism between partially and fully convective stars. We have selected 10 of the closest dM systems to determine the rotation velocities and the mean magnetic field strengths based on spectroscopic analysis of FeH lines of Wing-Ford transitions at 1 $\\mu$m observed with VLT/CRIRES. We also studied the quality of our spectroscopic model regarding atmospheric parameters including metallicity. A modified version of the Molecular Zeeman Library (MZL) was used to compute Land\\'e g-factors for FeH lines. Magnetic spectral synthesis was performed with the Synmast code. We confirmed previously...

  10. Influence of Cropping System Intensity on Dry Matter Yield and Nitrogen Concentration in Different Parts of Soybean Plant

    Directory of Open Access Journals (Sweden)

    Klaudija Carović

    2006-10-01

    Full Text Available Two-year investigations were conducted within the three-year maize-soybean-wheat crop rotation with the aim to assess the influence of two cropping systems, conditionally marked as high-input and reduced-input systems, on soybean dry matter yield and nitrogen concentration in its different plant parts. The high-input system was characterized by: ploughing at 30-32 cm, fertilization with 80 kg N and 130 P2O5 and K2O kg ha-1, weed control based on oxasulfuron and, if required, a corrective treatment with propachizafop and bentazone. The reduced-input system involved: ploughing at 20-22 cm, fertilization with a total of 40 kg N and 130 kg P2O5 and K2O kg ha-1, and only oxasulfuron-based weed control. Investigations involved two soybean genotypes: L 940596 and L 910631, vegetation group I. An identical monofactorial trial with four replications was set up in each cropping system. Cropping system intensity had a positive effect on leaf and stem dry matter mass in 2002, and on leaf and stem nitrogen concentration, whereas it had no effect on pod dry matter, seed yield and seed nitrogen concentrations in either year. The highest leaf dry matter was recorded in R4 development stage and that of stem and pod without seeds in R7 development stage. In both trial years, the highest nitrogen concentrations in leaf and stem were recorded in R1 development stage. In both trial years, higher pod nitrogen concentration was achieved in R4 development stage than in the R7 stage.

  11. Increasing Nitrogen Use Efficiency of Corn in Midwestern Cropping Systems

    Directory of Open Access Journals (Sweden)

    J.L. Hatfield

    2001-01-01

    Full Text Available Nitrogen (N loss from agricultural systems raises concerns about the potential impact of farming practices on environmental quality. N is a critical input to agricultural production. However, there is little understanding of the interactions among crop water use, N application rates, and soil types. This study was designed to quantify these interactions in corn (Zea mays L. grown in production-size fields in central Iowa on the Clarion-Nicollet-Webster soil association. Seasonal water use varied by soil type and N application rate. Yield varied with N application rate, with the highest average yield obtained at 100 kg ha-1. N use efficiency (NUE decreased with increasing N application rates, having values around 50%. Water use efficiency (WUE decreased as N fertilizer rates increased. Analysis of plant growth patterns showed that in the low organic matter soils (lower water-holding capacities, potential yield was not achieved because of water deficits during the grain-filling period. Using precipitation data coupled with daily water use throughout the season, lower organic matter soils showed these soils began to drain earlier in the spring and continued to drain more water throughout the season. The low NUE in these soils together with increased drainage lead to greater N loss from these soils. Improved management decisions have shown that it is possible to couple water use patterns with N application to increase both WUE and NUE.

  12. Can subsurface drip irrigation (SDI) be a competitive irrigation system in the Great Plains region for commodity crops

    Science.gov (United States)

    Subsurface drip irrigation (SDI) as with all microirrigation systems is typically only used on crops with greater value. In the U.S. Great Plains region, the typical irrigated crops are the cereal and oil seed crops and cotton. These crops have less economic revenue than typical microirrigated cro...

  13. Assessing nutritional diversity of cropping systems in African villages.

    Directory of Open Access Journals (Sweden)

    Roseline Remans

    Full Text Available BACKGROUND: In Sub-Saharan Africa, 40% of children under five years in age are chronically undernourished. As new investments and attention galvanize action on African agriculture to reduce hunger, there is an urgent need for metrics that monitor agricultural progress beyond calories produced per capita and address nutritional diversity essential for human health. In this study we demonstrate how an ecological tool, functional diversity (FD, has potential to address this need and provide new insights on nutritional diversity of cropping systems in rural Africa. METHODS AND FINDINGS: Data on edible plant species diversity, food security and diet diversity were collected for 170 farms in three rural settings in Sub-Saharan Africa. Nutritional FD metrics were calculated based on farm species composition and species nutritional composition. Iron and vitamin A deficiency were determined from blood samples of 90 adult women. Nutritional FD metrics summarized the diversity of nutrients provided by the farm and showed variability between farms and villages. Regression of nutritional FD against species richness and expected FD enabled identification of key species that add nutrient diversity to the system and assessed the degree of redundancy for nutrient traits. Nutritional FD analysis demonstrated that depending on the original composition of species on farm or village, adding or removing individual species can have radically different outcomes for nutritional diversity. While correlations between nutritional FD, food and nutrition indicators were not significant at household level, associations between these variables were observed at village level. CONCLUSION: This study provides novel metrics to address nutritional diversity in farming systems and examples of how these metrics can help guide agricultural interventions towards adequate nutrient diversity. New hypotheses on the link between agro-diversity, food security and human nutrition are

  14. NMR system and method having a permanent magnet providing a rotating magnetic field

    Science.gov (United States)

    Schlueter, Ross D [Berkeley, CA; Budinger, Thomas F [Berkeley, CA

    2009-05-19

    Disclosed herein are systems and methods for generating a rotating magnetic field. The rotating magnetic field can be used to obtain rotating-field NMR spectra, such as magic angle spinning spectra, without having to physically rotate the sample. This result allows magic angle spinning NMR to be conducted on biological samples such as live animals, including humans.

  15. 耕作方式对华北冬小麦-夏玉米周年产量和水分利用的影响%Effects of tillage methods on crop yield and water use characteristics in winter-wheat/summer-maize rotation system in the North China Plain

    Institute of Scientific and Technical Information of China (English)

    孔凡磊; 张海林; 翟云龙; 袁继超; 陈阜

    2014-01-01

    在冬小麦季设置秸秆不还田翻耕(CT)、秸秆还田翻耕(CTS)、秸秆还田旋耕(RTS)和免耕秸秆覆盖(NTS)4种处理,研究耕作方式对华北小麦-玉米两熟区作物周年产量和水分利用的影响。结果表明:耕作方式对当季冬小麦产量和水分利用影响显著,对夏玉米产量和水分利用影响不大,但秸秆还田提高了夏玉米产量。RTS、CTS、CT 3个处理小麦季产量差异不显著,而NTS由于有效穗数不足,产量显著低于其他处理;与CT相比, NTS周年产量平均减产5.13%, RTS增产2.69%, CTS增产2.33%。耕作方式对当季小麦土壤水分含量影响大,而对后茬夏玉米土壤水分含量的影响较小。NTS 提高了小麦季土壤水分含量,增加了土壤储水量,与CT相比,0~60 cm土壤储水量2010年和2011年分别增加39.07 mm和26.65 mm。从耗水构成来看,土壤水在冬小麦耗水中所占比例最大,其次为灌水和降水;而夏玉米耗水以降水为主,且降水中有一部分转化为土壤水储存起来。NTS提高了冬小麦季土壤储水量,降低了土壤水分的消耗,冬小麦季耗水最少。与CT相比, NTS小麦季平均节水22.40 mm,周年耗水量也以NTS最少;但NTS冬小麦产量降低导致其小麦季和周年水分利用效率均最低。从作物周年产量和水分利用的角度来看,如何提高免耕秸秆覆盖小麦季产量,进而提高周年产量,发挥其节水优势,是该耕作模式在华北地区冬小麦-夏玉米两熟区推广应用亟需解决的关键问题。%Four tillage methods - conventional tillage without straw (CT), conventional tillage with straw incorporation (CTS), rotary tillage with straw incorporation (RTS) and no-tillage with straw mulch (NTS)-were used to study the effects of tillage on annual yield and water use efficiency in winter-wheat/summer-maize cultivation system in the North China Plain. Results showed that different tillage methods significantly influenced winter wheat

  16. Impact of imazamox containing herbicides on the development of resistance in black-grass (Alopecurus myosuroides Huds. within an oilseed rape / wheat crop rotation

    Directory of Open Access Journals (Sweden)

    Rosenhauer, Marie

    2016-02-01

    Full Text Available The application of imazamox as an herbicide in oilseed-rape got possible due to the introduction of Clearfield oilseed-rape varieties which are tolerant to ALS inhibitors. The question of this investigation was, if the broader use of ALS-inhibitors increases the selection pressure on herbicide resistant weeds and increases their occurrence in the crop rotation. An outdoor container trial with 30 containers (350 l, 0,7 m² was performed, starting in autumn 2011. A winter wheat – oilseed-rape rotation was simulated for four years. Three different black-grass biotypes with different resistance pattern and 5 different herbicide programmes were analysed in this study in order to investigate the population dynamics of target-site resistance (TSR and the development of metabolic resistance. The trials showed interactions between the black-grass biotype and the herbicide strategy on the increase of the black-grass density. There was no interaction due to the use of propyzamide. The frequency of target-site resistance to ACCase inhibitors increased for the corresponding biotypes independently of the herbicide strategy during the trial period. The low frequency of ALS-TSR at trial start did not change during the trial period, independently of the use of imazamox in the oil-seed rape cultivation. The comparison of the resistance factors between the original biotypes and the seeds harvested after the four year container trial showed increasing resistances against pinoxaden for all biotypes. Within the different black-grass biotypes there was a slightly decrease as well as an increase in imazamox efficacy observed. There was no significant increase of meso- + iodosulfuron resistance compared to the original biotypes from 2011 caused by different herbicide treatments. The results indicated that the integration of imazamox tolerant oilseed rape in winter wheat crop rotations did not necessarily increase the development of herbicide resistant black-grass.

  17. Indicators of soil quality in the implantation of no-till system with winter crops

    Directory of Open Access Journals (Sweden)

    Marco Antonio Nogueira

    Full Text Available We assessed the effect of different winter crops on indicators of soil quality related to C and N cycling and C fractions in a Rhodic Kandiudult under no-till system at implantation, during two growing seasons, in Londrina PR Brazil. The experimental design was randomized blocks with split-plot in time arrangement, with four replications. The parcels were the winter crops: multicropping of cover crops with black oat (Avena strigosa, hairy vetch (Vicia villosa and fodder radish (Raphanus sativus; sunflower (Heliantus annuus intercropped with Urochloa ruziziensis; corn (Zea mays intercropped with Urochloa; and corn; fodder radish; or wheat (Triticum aestivum as sole crops. The subplots were the years: 2008 and 2009. Determinations consisted of total organic C, labile and resistant C, total N, microbial biomass C and N, the C/N ratio of soil organic matter, and the microbial quotient (qMic, besides microbiological and biochemical attributes, assessed only in 2009. The attributes significantly changed with the winter crops, especially the multicropping of cover crops and fodder radish, as well as effect of years. Despite stimulating the microbiological/biochemical activity, fodder radish cropping decreased the soil C in the second year, likewise the wheat cropping. The multicropping of cover crops in winter is an option for management in the establishment of no-till system, which contributes to increase the concentrations of C and stimulate the soil microbiological/biochemical activity.

  18. Water Erosion in Relation with Soil Management System and Crop Sequence during 20 Years on an Inceptisol in South Brazil

    Science.gov (United States)

    Bertol, I.; Schick, J.; Barbosa, F. T.; Paz-Ferreiro, J.; Flores, M. T.; Paz González, A.

    2012-04-01

    Soil erosion still remains persistent at the world scale, even if big efforts have been done to control and reduce it, mainly using soil crop residues to protect soil surface. Although in South Brazil the main management system for most crops is no tillage and direct drilling, water erosion prevails as the most important soil erosion type, which is due both, to the high erosivity and the evenly distribution of rainfall over the year. Moreover, some crops are still grown under soil tillage systems consisting of ploughing, harrowing and less frequently chiselling. Starting 1992, a field experiment under natural rainfall has been conducted on an Inceptisol located in Lages, Santa Catarina State, Brazil, which objective was to assess rainfall water erosion. Two soil cover conditions and four soil management systems were studied: I) a crop rotation, which included oats (Avena strigosa), soybean (Glycine max), common vetch (Vicia sativa), maize (Zea mays), fodder radish (Raphanus sativus) and common bean (Phaseolus vulgaris) under the following soil management types: 1) ploughing plus two levelling operations (CT), chiselling plus levelling (RT) and direct drilling with no tillage (NT), and II) bare soil (BS) without crop cover tilled by ploughing plus two levelling. In more than 90% of the study cases, soil losses were collected for single rain events with erosive power, whose erosivity was calculated. Total rain recorded during the 20 year experimental period was approximately 66,400 mm, which is equivalent to roughly 105,700, MJ mm ha-1 h-1 (EI30), whereas soil losses in the BS treatment were higher than 1,700 t.ha-1. On average, soil losses under RT treatment showed a 92% reduction in relation with BS, whereas under CT the reduction in relation to BS was about 66%. Soil management by direct drilling (NT) was the most efficient system to minimize water erosion, as soil losses decreased about 98% when compared with BS. Moreover, soil management systems with a crop

  19. Improving the reliability of stator insulation system in rotating machines

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, G.K.; Sedding, H.G.; Culbert, I.M. [Ontario Hydro, Toronto, ON, (Canada)

    1997-07-01

    Reliable performance of rotating machines, especially generators and primary heat transport pump motors, is critical to the efficient operation on nuclear stations. A significant number of premature machine failures have been attributed to the stator insulation problems. Ontario Hydro has attempted to assure the long term reliability of the insulation system in critical rotating machines through proper specifications and quality assurance tests for new machines and periodic on-line and off-line diagnostic tests on machines in service. The experience gained over the last twenty years is presented in this paper. Functional specifications have been developed for the insulation system in critical rotating machines based on engineering considerations and our past experience. These specifications include insulation stress, insulation resistance and polarization index, partial discharge levels, dissipation factor and tip up, AC and DC hipot tests. Voltage endurance tests are specified for groundwall insulation system of full size production coils and bars. For machines with multi-turn coils, turn insulation strength for fast fronted surges in specified and verified through tests on all coils in the factory and on samples of finished coils in the laboratory. Periodic on-line and off-line diagnostic tests were performed to assess the condition of the stator insulation system in machines in service. Partial discharges are measured on-line using several techniques to detect any excessive degradation of the insulation system in critical machines. Novel sensors have been developed and installed in several machines to facilitate measurements of partial discharges on operating machines. Several off-line tests are performed either to confirm the problems indicated by the on-line test or to assess the insulation system in machines which cannot be easily tested on-line. Experience with these tests, including their capabilities and limitations, are presented. (author)

  20. Responses of Nitrogen Utilization and Apparent Nitrogen Loss to Different Control Measures in the Wheat and Maize Rotation System

    Science.gov (United States)

    Peng, Zhengping; Liu, Yanan; Li, Yingchun; Abawi, Yahya; Wang, Yanqun; Men, Mingxin; An-Vo, Duc-Anh

    2017-01-01

    Nitrogen (N) is an essential macronutrient for plant growth and excessive application rates can decrease crop yield and increase N loss into the environment. Field experiments were carried out to understand the effects of N fertilizers on N utilization, crop yield and net income in wheat and maize rotation system of the North China Plain (NCP). Compared to farmers’ N rate (FN), the yield of wheat and maize in reduction N rate by 21–24% based on FN (RN) was improved by 451 kg ha-1, N uptakes improved by 17 kg ha-1 and net income increased by 1671 CNY ha-1, while apparent N loss was reduced by 156 kg ha-1. The controlled-release fertilizer with a 20% reduction of RN (CRF80%), a 20% reduction of RN together with dicyandiamide (RN80%+DCD) and a 20% reduction of RN added with nano-carbon (RN80%+NC) all resulted in an improvement in crop yield and decreased the apparent N losses compared to RN. Contrasted with RN80%+NC, the total crop yield in RN80%+DCD improved by 1185 kg ha-1, N uptake enhanced by 9 kg ha-1 and net income increased by 3929 CNY ha-1, while apparent N loss was similar. Therefore, a 37–39% overall decrease in N rate compared to farmers plus the nitrification inhibitor, DCD, was effective N control measure that increased crop yields, enhanced N efficiencies, and improved economic benefits, while mitigating apparent N loss. There is considerable scope for improved N use effieincy in the intensive wheat -maize rotation of the NCP. PMID:28228772

  1. [Responses of rice-wheat rotation system in south Jiangsu to organic-inorganic compound fertilizers].

    Science.gov (United States)

    Tian, Heng-Da; Zhang, Li; Zhang, Jian-Chao; Wang, Qiu-Jun; Xu, Da-Bing; Yibati, Halihashi; Xu, Jia-Le; Huang, Qi-Wei

    2011-11-01

    In 2006-2007, a field trial was conducted to study the effects of applying three kinds of organic-inorganic compound fertilizers [rapeseed cake compost plus inorganic fertilizers (RCC), pig manure compost plus inorganic fertilizers (PMC), and Chinese medicine residues plus inorganic fertilizers (CMC)] on the crop growth and nitrogen (N) use efficiency of rice-wheat rotation system in South Jiangsu. Grain yield of wheat and rice in the different fertilization treatments was significantly higher than the control (no fertilization). In treatments RCC, PMC and CMC, the wheat yield was 13.1%, 32.2% and 39.3% lower than that of the NPK compound fertilizer (CF, 6760 kg x hm(-2)), respectively, but the rice yield (8504-9449 kg x hm(-2)) was significantly higher than that (7919 kg x hm(-2)) of CF, with an increment of 7.4%-19.3%. In wheat season, the aboveground dry mass, N accumulation, and N use efficiency in treatments RCC, PMC, and CMC were lower than those of CF, but in rice season, these parameters were significantly higher than or as the same as CF. In sum, all the test three compound fertilizers had positive effects on the rice yield and its nitrogen use efficiency in the rice-wheat rotation system, being most significant for RCC.

  2. All-optical animation projection system with rotating fieldstone

    Science.gov (United States)

    Ishii, Yuko; Takayama, Yoshihisa; Kodate, Kashiko

    2007-06-01

    A simple and compact rewritable holographic memory system using a fieldstone of Ulexite is proposed. The role of the fieldstone is to impose random patterns on the reference beam to record plural images with the random-reference multiplexing scheme. The operations for writing and reading holograms are carried out by simply rotating the fieldstone in one direction. One of the features of this approach is found in a way to generate random patterns without computer drawings. The experimental study confirms that our system enables the smooth readout of the stored images one after another so that the series of reproduced images are projected as an animation.

  3. Bounded Nonlinear Control of a Rotating Pendulum System

    Science.gov (United States)

    Luyckx, L.; Loccufier, M.; Noldus, E.

    2004-08-01

    We are interested in the output feedback control of mechanical systems governed by the Euler-Lagrange formalism. The systems are collocated actuator-sensor controlled and underactuated. We present a design method by means of a specific example : the set point control of a rotating pendulum. We use constrained output feedback, whereby the control inputs satisfy a priori imposed upper bounds. The closed loop stability analysis relies on the direct method of Liapunov. This results in a frequency criterion on the controller's linear dynamic component and some restrictions on its nonlinearities. The control parameters are tuned for maximizing closed loop damping.

  4. Resource flows, crops and soil fertility management in smallholder farming systems in semi-arid Zimbabwe

    NARCIS (Netherlands)

    Ncube, B.; Twomlow, S.J.; Dimes, J.P.; Wijk, van M.T.; Giller, K.E.

    2009-01-01

    Poor soil fertility and erratic rains are major constraints to crop production in semi-arid environments. In the smallholder farming systems of sub-Saharan Africa, these constraints are manifested in frequent crop failures and endemic food insecurity. We characterized a semi-arid smallholder farming

  5. Impacts of organic conservation tillage systems on crops, weeds, and soil quality

    Science.gov (United States)

    Organic farming has been identified as promoting soil quality even though tillage is used for weed suppression. Adopting conservation tillage practices can enhance soil quality in cropping systems where synthetic agrichemicals are used for crop nutrition and weed control. Attempts have been made t...

  6. Grazing winter rye cover crop in a cotton no-till system: yield and economics

    Science.gov (United States)

    Winter cover crop adoption in conservation management systems continues to be limited in the US but could be encouraged if establishment costs could be offset. A 4-yr field experiment was conducted near Watkinsville, Georgia in which a rye (Secale cereale L.) cover crop was either grazed by catt...

  7. The Myth of Coexistence: Why Transgenic Crops Are Not Compatible With Agroecologically Based Systems of Production

    Science.gov (United States)

    Altieri, Miguel

    2005-01-01

    The coexistence of genetically modified (GM) crops and non-GM crops is a myth because the movement of transgenes beyond their intended destinations is a certainty, and this leads to genetic contamination of organic farms and other systems. It is unlikely that transgenes can be retracted once they have escaped, thus the damage to the purity of…

  8. Integrated crop-livestock systems: a key to sustainable intensification in Africa

    NARCIS (Netherlands)

    Duncan, A.J.; Tarawali, S.A.; Thorne, P.J.; Valbuena, D.F.; Descheemaeker, K.K.E.; Homann-Kee Tui, S.

    2013-01-01

    Mixed crop-livestock systems provide livelihoods for a billion people and produce half the world’s cereal and around a third of its beef and milk. Market orientation and strong and growing demand for food provide powerful incentives for sustainable intensification of both crop and livestock enterpri

  9. Understanding cropping systems in the semi-arid environments of Zimbabwe: options for soil fertility management

    NARCIS (Netherlands)

    Ncube, B.

    2007-01-01

    African smallholder farmers face perennial food shortages due to low crop yields. The major cause of poor crop yields is soil fertility decline. The diversity of sites and soils between African farming systems isgreat,therefore strategies to solve soil fertility problems sho

  10. Grass-clover undersowing affects nitrogen dynamics in a grain legume–cereal arable cropping system

    DEFF Research Database (Denmark)

    Hauggaard-Nielsen, Henrik; Mundus, Simon; Jensen, Erik Steen

    2012-01-01

    A field experiment was carried out in an arable organic cropping system and included a sequence with sole cropped fababean (Vicia faba L.), lupin (Lupinus angustifolius L.), pea (Pisum sativum L.), oat (Avena sativa L.) and pea–oat intercropping with or without an undersown perennial ryegrass...

  11. Cover Crop and Liquid Manure Effects on Soil Quality Indicators in a Corn Silage System.

    Science.gov (United States)

    Due to a lack of surface residue and organic matter inputs, continuous corn (Zea mays L.) silage production is one of the most demanding cropping systems imposed on our soil resources. In this study, our objective was to determine if using cover/companion crops and/or applying low-solids liquid dair...

  12. Long-Term Effect of Crop Rotation on Soybean in a Field Infested with Meloidogyne arenaria and Heterodera glycines

    OpenAIRE

    Weaver, D. B.; Rodríguez-Kábana, R.; Carden, E. L.

    1989-01-01

    Previous cropping sequence (corn-soybean vs. soybean-soybean) and aldicarb effects on soybean yield and nematode numbers at harvest for soybean cultivars with various combinations of nematode resistance were determined in 1988 in a sandy loam soil infested with Meloidogyne arenaria race 2 and Heterodera glycines races 3 and 4 at Elberta, Alabama. Yield and nematode numbers differed among cultivars with 'Leflore' having the highest yield. Aldicarb treatment resulted in increased soybean yield ...

  13. Conversão e balanço energético de sistemas de rotação de culturas para triticale, sob plantio direto Energy and balance conversion of crop rotation systems for triticale , under no-tillage

    Directory of Open Access Journals (Sweden)

    Henrique Pereira dos Santos

    2000-03-01

    Full Text Available Na agricultura moderna, interessam sistemas de produção eficientes no uso da energia. Objetivou-se avaliar a conversão e o balanço energético de cinco sistemas de rotação de culturas envolvendo o triticale. Os sistemas avaliados, no período de 1987 a 1991, foram: I (triticale/soja, II (triticale/soja e aveia preta/soja, III (triticale/soja e ervilhaca/milho, IV (triticale/ soja, ervilhaca/milho e aveia preta/soja e V (triticale/soja, triticale/soja, ervilhaca/milho e aveia preta/soja. Em 1990, nos sistemas II, IV e V, a aveia preta foi substituída por aveia branca. O experimento foi estabelecido em plantio direto, em delineamento de blocos ao acaso, com três repetições e parcelas com área útil de 24 m². Na média do período de 1987 a 1989, o sistema III apresentou conversão (9,30 e balanço energético (23.860 Mcal/ha maiores do que os demais sistemas estudados (I: 5,38, II: 5,02, IV: 8,12 e V: 7,37; I: 18.067 Mcal/ha, II: 13.790 Mcal/ha, IV: 19.875 Mcal/ha e V: 19.264 Mcal/ha, respectivamente. Nesse período, as condições climáticas transcorreram normalmente. Na média do período de 1990 a 1991, não houve diferenças significativas entre as médias para conversão e para balanço energético. Nesse período, as condições climáticas foram adversas às culturas em estudo.Efficient energy conversion production systems are important for modern agriculture. The objetive was to evaluate the energy conversion and balance of five rotation systems that included triticale. The evaluated systems, from 1987 to 1991, were: I (triticale/soybean, II (triticale/soybean and black oats/soybean, III (triticale/soybean and common vetch/corn, IV (triticale/soybean, common vetch/corn, and black oats/soybean, and V (triticale/soybean, triticale/soybean, common vetch/corn, and black oats/ soybean. In 1990, black oats was replaced by white oats in systems II, IV, and V. The experiment was set up under no-tillage, using a randomized block design

  14. Failure Accommodation Tested in Magnetic Suspension Systems for Rotating Machinery

    Science.gov (United States)

    Provenza, Andy J.

    2000-01-01

    The NASA Glenn Research Center at Lewis Field and Texas A&M University are developing techniques for accommodating certain types of failures in magnetic suspension systems used in rotating machinery. In recent years, magnetic bearings have become a viable alternative to rolling element bearings for many applications. For example, industrial machinery such as machine tool spindles and turbomolecular pumps can today be bought off the shelf with magnetically supported rotating components. Nova Gas Transmission Ltd. has large gas compressors in Canada that have been running flawlessly for years on magnetic bearings. To help mature this technology and quiet concerns over the reliability of magnetic bearings, NASA researchers have been investigating ways of making the bearing system tolerant to faults. Since the potential benefits from an oil-free, actively controlled bearing system are so attractive, research that is focused on assuring system reliability and safety is justifiable. With support from the Fast Quiet Engine program, Glenn's Structural Mechanics and Dynamics Branch is working to demonstrate fault-tolerant magnetic suspension systems targeted for aerospace engine applications. The Flywheel Energy Storage Program is also helping to fund this research.

  15. Tillage System and Cover Crop Effects on Soil Quality

    DEFF Research Database (Denmark)

    Abdollahi, Lotfollah; Munkholm, Lars Juhl

    2014-01-01

    ), and moldboard plowing (MP) with and without a cover crop were evaluated in a long-term experiment on a sandy loam soil in Denmark. Chemical, physical, and biological soil properties were measured in the spring of 2012. The field measurements included mean weight diameter (MWD) after the drop-shatter test......, penetration resistance, and visual evaluation of soil structure (VESS). In the laboratory, aggregate strength, water-stable aggregates (WSA), and clay dispersibility were measured. The analyzed chemical and biological properties included soil organic C (SOC), total N, microbial biomass C, labile P and K...... in terms of greater MWD, VESS, WSA, aggregate tensile strength, and rupture energy. Five years of using a cover crop alleviated plow pan compaction at the 20- to 40-cm depth by reducing penetration resistance. A significant interaction between tillage and cover crop treatments indicated the potential...

  16. Effect of intercropping period management on runoff and erosion in a maize cropping system.

    Science.gov (United States)

    Laloy, Eric; Bielders, C L

    2010-01-01

    The management of winter cover crops is likely to influence their performance in reducing runoff and erosion during the intercropping period that precedes spring crops but also during the subsequent spring crop. This study investigated the impact of two dates of destruction and burial of a rye (Secale cereale L.) and ryegrass (Lolium multiflorum Lam.) cover crop on runoff and erosion, focusing on a continuous silage maize (Zea mays L.) cropping system. Thirty erosion plots with various intercrop management options were monitored for 3 yr at two sites. During the intercropping period, cover crops reduced runoff and erosion by more than 94% compared with untilled, post-maize harvest plots. Rough tillage after maize harvest proved equally effective as a late sown cover crop. There was no effect of cover crop destruction and burial dates on runoff and erosion during the intercropping period, probably because rough tillage for cover crop burial compensates for the lack of soil cover. During two of the monitored maize seasons, it was observed that plots that had been covered during the previous intercropping period lost 40 to 90% less soil compared with maize plots that had been left bare during the intercropping period. The burial of an aboveground cover crop biomass in excess of 1.5 t ha(-1) was a necessary, yet not always sufficient, condition to induce a residual effect. Because of the possible beneficial residual effect of cover crop burial on erosion reduction, the sowing of a cover crop should be preferred over rough tillage after maize harvest.

  17. Simulation of nitrogen leaching from a fertigated crop rotation in a Mediterranean climate using the EU-Rotate_N and Hydrus-2D models

    DEFF Research Database (Denmark)

    Doltra, Jordi; Nuñoz, P

    2010-01-01

    an experiment where four N fertigation levels were applied to a bell pepper-cauliflower-Swiss chard rotation in a sandy loam soil. All the input data were obtained from measurements, transfer functions or were included in the model databases. Model runs were without specific site calibration. The use of soil...... input parameters based on the same pedotransfer functions in both models resulted in a very similar simulation of soil water content in spite of the different nature of the approaches. Good correlations were found between the simulated water draining below 60 cm and that calculated by water balance......-scaling the quantification of N leaching from a field level to regional and national levels, identifying best management strategies in relation to N use from an environmental and economic perspective...

  18. Comparative Economic Study of Mixed and Sole Cassava Cropping Systems in Nigeria

    Directory of Open Access Journals (Sweden)

    J. O. Ajayi

    2014-12-01

    Full Text Available Agricultural economists continue to argue if mixed or sole cassava cropping system is more economically profitable and in terms of yield and returns to farmers particularly for Nigeria which is the world’s largest producer of the crop. The study was carried out to analyse the economics comparatively of mixed and sole cassava cropping systems in Nigeria. The study made use of both primary and secondary data. Primary data were collected with the aid of well-structured questionnaires assisted with interview schedules. Field data collection was conducted between March and April, 2014. Multi-stage sampling technique was used to select four hundred and eighty (480 respondents across the six major cassava-producing states in Nigeria (Benue, Cross Rivers, Enugu, Kogi, Ondo, and Oyo. Data collected were analysed using descriptive statistics and comparative budgetary analysis. The study showed that mixed cropping system is more male-dominated than sole cropping system. The study also revealed that sole cassava cropping system is more economically profitable than mixed cassava cropping system while the later provides opportunities of all-year-round farm incomes to serve as a better poverty- alleviating mechanism.

  19. METRIC OF ACCELERATING AND ROTATING REFERENCE SYSTEMS IN GENERAL RELATIVITY

    Directory of Open Access Journals (Sweden)

    Trunev A. P.

    2015-03-01

    Full Text Available Metric describing the accelerated and rotating reference system in general relativity in the case of an arbitrary dependence of acceleration and angular velocity on time has been proposed. It is established that the curvature tensor in such metrics is zero, which corresponds to movement in the flat spaces. It is shown that the motion of test bodies in the metric accelerated and rotating reference system in general relativity is similarly to the classical motion in non-inertial reference frame. Consequently, there exist a metric in general relativity, in which the Coriolis theorem and classic velocity-addition formula are true. This means that classical mechanics is accurate rather than approximate model in general relativity. A theory of potential in non-inertial reference systems in general relativity is considered. The numerical model of wave propagation in non-inertial reference frames in the case when potential depending of one, two and three spatial dimensions has been developed. It is shown in numerical experiment that the acceleration of the reference system leads to retardation effects, as well as to a violation of the symmetry of the wave front, indicating that there is local change of wave speed

  20. Rhizo-lysimetry: facilities for the simultaneous study of root behaviour and resource use by agricultural crop and pasture systems

    Directory of Open Access Journals (Sweden)

    Eberbach Philip L

    2013-01-01

    Full Text Available Abstract Background Rhizo-lysimeters offer unique advantages for the study of plants and their interactions with soils. In this paper, an existing facility at Charles Sturt University in Wagga Wagga Australia is described in detail and its potential to conduct both ecophysiological and ecohydrological research in the study of root interactions of agricultural crops and pastures is quantitatively assessed. This is of significance to future crop research efforts in southern Australia, in light of recent significant long-term drought events, as well as potential impacts of climate change as predicted for the region. The rhizo-lysimeter root research facility has recently been expanded to accommodate larger research projects over multiple years and cropping rotations. Results Lucerne, a widely-grown perennial pasture in southern Australia, developed an expansive root system to a depth of 0.9 m over a twelve month period. Its deeper roots particularly at 2.05 m continued to expand for the duration of the experiment. In succeeding experiments, canola, a commonly grown annual crop, developed a more extensive (approximately 300% root system than wheat, but exhibited a slower rate of root elongation at rates of 7.47 x 10–3 m day–1 for canola and 1.04 x10–2 m day–1 for wheat. A time domain reflectometry (TDR network was designed to accurately assess changes in soil water content, and could assess water content change to within 5% of the amount of water applied. Conclusions The rhizo-lysimetry system provided robust estimates of root growth and soil water change under conditions representative of a field setting. This is currently one of a very limited number of global research facilities able to perform experimentation under field conditions and is the largest root research experimental laboratory in the southern hemisphere.

  1. Effects of different tillage and straw return on soil organic carbon in a rice-wheat rotation system.

    Directory of Open Access Journals (Sweden)

    Liqun Zhu

    Full Text Available Soil management practices, such as tillage method or straw return, could alter soil organic carbon (C contents. However, the effects of tillage method or straw return on soil organic C (SOC have showed inconsistent results in different soil/climate/cropping systems. The Yangtze River Delta of China is the main production region of rice and wheat, and rice-wheat rotation is the most important cropping system in this region. However, few studies in this region have been conducted to assess the effects of different tillage methods combined with straw return on soil labile C fractions in the rice-wheat rotation system. In this study, a field experiment was used to evaluate the effects of different tillage methods, straw return and their interaction on soil total organic C (TOC and labile organic C fractions at three soil depths (0-7, 7-14 and 14-21 cm for a rice-wheat rotation in Yangzhong of the Yangtze River Delta of China. Soil TOC, easily oxidizable C (EOC, dissolved organic C (DOC and microbial biomass C (MBC contents were measured in this study. Soil TOC and labile organic C fractions contents were significantly affected by straw returns, and were higher under straw return treatments than non-straw return at three depths. At 0-7 cm depth, soil MBC was significantly higher under plowing tillage than rotary tillage, but EOC was just opposite. Rotary tillage had significantly higher soil TOC than plowing tillage at 7-14 cm depth. However, at 14-21 cm depth, TOC, DOC and MBC were significantly higher under plowing tillage than rotary tillage except for EOC. Consequently, under short-term condition, rice and wheat straw both return in rice-wheat rotation system could increase SOC content and improve soil quality in the Yangtze River Delta.

  2. Effects of different tillage and straw return on soil organic carbon in a rice-wheat rotation system.

    Science.gov (United States)

    Zhu, Liqun; Hu, Naijuan; Yang, Minfang; Zhan, Xinhua; Zhang, Zhengwen

    2014-01-01

    Soil management practices, such as tillage method or straw return, could alter soil organic carbon (C) contents. However, the effects of tillage method or straw return on soil organic C (SOC) have showed inconsistent results in different soil/climate/cropping systems. The Yangtze River Delta of China is the main production region of rice and wheat, and rice-wheat rotation is the most important cropping system in this region. However, few studies in this region have been conducted to assess the effects of different tillage methods combined with straw return on soil labile C fractions in the rice-wheat rotation system. In this study, a field experiment was used to evaluate the effects of different tillage methods, straw return and their interaction on soil total organic C (TOC) and labile organic C fractions at three soil depths (0-7, 7-14 and 14-21 cm) for a rice-wheat rotation in Yangzhong of the Yangtze River Delta of China. Soil TOC, easily oxidizable C (EOC), dissolved organic C (DOC) and microbial biomass C (MBC) contents were measured in this study. Soil TOC and labile organic C fractions contents were significantly affected by straw returns, and were higher under straw return treatments than non-straw return at three depths. At 0-7 cm depth, soil MBC was significantly higher under plowing tillage than rotary tillage, but EOC was just opposite. Rotary tillage had significantly higher soil TOC than plowing tillage at 7-14 cm depth. However, at 14-21 cm depth, TOC, DOC and MBC were significantly higher under plowing tillage than rotary tillage except for EOC. Consequently, under short-term condition, rice and wheat straw both return in rice-wheat rotation system could increase SOC content and improve soil quality in the Yangtze River Delta.

  3. Sustainability issues on rice–wheat cropping system

    Directory of Open Access Journals (Sweden)

    Rajan Bhatt

    2016-03-01

    In this review, an attempt was made to highlight different issues resulted from the practise of intensive rice–wheat cropping sequence of the region, which must be considered while framing and implementing any integrated approach/project such as conservation agriculture for improving the productions, profits and sustainability of RWCS in the region.

  4. Tillage System and Cover Crop Effects on Soil Quality

    DEFF Research Database (Denmark)

    Abdollahi, Lotfollah; Munkholm, Lars Juhl

    2014-01-01

    Information about the quantitative effect of conservation tillage combined with a cover crop on soil structure is still limited. This study examined the effect of these management practices on soil pore characteristics of a sandy loam soil in a long-term field trial. The tillage treatments (main...... plots) included direct drilling (D), harrowing to a depth of 8 to 10 cm (H), and moldboard plowing (MP). The cover crop treatments were subplot with cover crop (+CC) and without cover crop (−CC). Minimally disturbed soil cores were taken from the 4- to 8-, 12- to 16-, and 18- to 27-cm depth intervals...... in the spring of 2012 before cultivation. Soil water retention and air permeability were measured for matric potentials ranging from −1 to −30 kPa. Gas diffusivity was measured at −10 kPa. Computed tomography (CT) scanning was also used to characterize soil pore characteristics. At the 4- to 8- and 18- to 27-cm...

  5. Integrating insect-resistant GM Crops in pest management systems

    Science.gov (United States)

    In 2006, GM cotton and maize with insect resistance were grown on 12.1 and 20.1 million hectares in 9 and 13 countries, respectively. These insect resistant GM crops produce various Cry toxins from Bacillus thuringiensis (Bt) and provide highly selective and effective control of lepidopteran and col...

  6. Land use change and crop rotation analysis of a government well district in Rashda village – Dakhla Oasis, Egypt based on satellite data

    Directory of Open Access Journals (Sweden)

    H. Kato

    2012-12-01

    The land use change analysis showed that the extension of cultivated land was already completed by the 1980s in the North and South subdistricts, after which it spread toward the West. Because the altitude in the West subdistrict is lower than the wells, irrigation water could be distributed adequately if the condition of the irrigation channel was well maintained. The relationship between the irrigation level and plant production was not favorable in the West compared with other subdistricts. The cultivated area in the West district has been increasing since the 1970s. According to the crop rotation analysis, the different productivity of the subdistricts was caused by several factors, including the land altitude and the distance from the well, as well as other factors such as social relationships in the village.

  7. New weed control strategies in maize considering narrow crop rotations with maize, greater ALSresistance in common weeds and application restrictions with regard to active substance

    Directory of Open Access Journals (Sweden)

    Ewert, Katrin

    2014-02-01

    Full Text Available Many herbicides with different HRAC-groups are available for weed control in maize. Because of narrow maize crop rotation summer weeds and warmth loving weeds are encouraged. On the other hand the new confirmed cases of an ALS target site resistance in the weed species Echinochloa crus-galli and Amaranthus retroflexus in Brandenburg, Stellaria media in Saxony and Matricaria recutita and Tripleurospermum perforatum in Brandenburg and Thuringia, warn that in the future the sulfonylureas must be used only according to the management of herbicide resistance. In this way the selection of resistant weed biotypes will be prevented. Moreover in protected water areas it may be a requirement to reduce and to substitute the input of some active substances, for example terbuthylazine and bentazon. The control of E. crus-galli and P. convolvulus with non-sulfonylurea or/and non-terbuthylazine herbicides according to management of herbicide resistance will be discussed.

  8. An Air Bearing Rotating Coil Magnetic Measurement System

    CERN Document Server

    Gottschalk, Stephen C; Taylor, David J; Thayer, William

    2005-01-01

    This paper describes a rotating coil magnetic measurement system supported on air bearings. The design is optimized for measurements of 0.1micron magnetic centerline changes on long, small aperture quadrupoles. Graphite impregnated epoxy resin is used for the coil holder and coil winding forms. Coil holder diameter is 11 mm with a length between supports of 750mm. A pair of coils is used to permit quadrupole bucking during centerline measurements. Coil length is 616mm, inner radius 1.82mm, outer radius 4.74mm. The key features of the mechanical system are simplicity; air bearings for accurate, repeatable measurements without needing warm up time and a vibration isolated stand that uses a steel-topped Newport optical table with air suspension. Coil rotation is achieved by a low noise servo motor controlled by a standalone Ethernet servo board running custom servo software. Coil calibration procedures that correct wire placement errors, tests for mechanical resonances, and other system checks will also be discu...

  9. Produção de trigo e triticale em rotações de sequeiro Wheat and triticale in crop rotations

    Directory of Open Access Journals (Sweden)

    Carlos Castro

    2008-01-01

    Full Text Available Apresentam-se os resultados de um ensaio de rotações que decorreu durante dez anos em Vila Real (Trás-os-Montes. O ensaio incluiu a rotação tradicional das condições de sequeiro de Trás-os-Montes, cereal-alqueive (TA, e rotações alternativas susceptíveis de serem adoptadas nestas condições, cereal-leguminosa (TL, cereal-consociação forrageira (TC e cereal-prado de sequeiro (TP. Os cereais das rotações foram o trigo e, posteriormente, o triticale. Determinaram-se e analisaram-se as produções de grão e palha, os teores de nutrientes do grão e da palha e acompanharam-se os parâmetros do solo, pH, matéria orgânica e os teores de P2 O 5, K2 O e bases de troca. Destacam-se alguns resultados importantes, tais como: as produções de grão de cereal das rotações não mostrarem diferenças significativas entre si; a produção de palha da rotação TL ser superior às das restantes; o trigo cultivado após prado de sequeiro não dispensar a adubação azotada; as rotações conduzirem a modificações dos teores de matéria orgânica, cálcio de troca ou do valor do pH do solo, factores a que se deve atender, caso a rotação se prolongue por muitos anos.The results of a field trial of crop rotations conducted over a period of ten years in Vila Real (Northeast Portugal are presented. The rotations tested were cereal-cultivated fallow (TA, traditional in rain-fed conditions of the region, and alternative rotations that could be adopted in these conditions: cereal-grain legume crop (TL, cereal-forage mixture (TC and cereal-rain-fed pasture (TP. The cereals were wheat and, later, triticale. Grain, straw and aerial biomass yields were evaluated together with concentrations of nutrients. The soil parameters studied were pH, organic matter and P 2 O 5, K2O and exchange cations. Wheat straw yield of TL rotation was higher than that of the others. Wheat from TP rotation still requires nitrogen fertilization. The soils of the different

  10. Effects of sewage sludge on the yield of plants in the rotation system of wheat-white head cabbage-tomato

    Directory of Open Access Journals (Sweden)

    Mehmet Arif Özyazıcı

    2013-01-01

    Full Text Available This research was carried to determine the effects of sewage sludge applications on the yield and yield components of plants under crop rotation system. The field experiments were conducted in the Bafra Plain, located in the north region of Turkey. In this research, the “wheat-white head cabbage-tomato” crop rotation systems have been examined and the same crop rotation has been repeated in two separate years and field trials have been established. Seven treatments were compared: a control without application of sludge nor nitrogen fertilization, a treatment without sludge, but nitrogen and phosphorus fertilization, applied at before sowing of wheat and five treatments where, respectively 10, 20, 30, 40 and 50 tons sludge ha-1. The experimental design was a randomized complete block with three replications. The results showed that all the yield components of wheat and yield of white head cabbage and tomato increased significantly with increasing rates of sewage sludge as compared to control. As a result, 20 t ha-1 of sewage sludge application could be recommended the suitable dose for the rotation of wheat-white head cabbage-tomato in soil and climatic conditions of Bafra Plain.

  11. Assessment of the Spatial and Temporal Variations of Water Quality for Agricultural Lands with Crop Rotation in China by Using a HYPE Model.

    Science.gov (United States)

    Yin, Yunxing; Jiang, Sanyuan; Pers, Charlotta; Yang, Xiaoying; Liu, Qun; Yuan, Jin; Yao, Mingxing; He, Yi; Luo, Xingzhang; Zheng, Zheng

    2016-03-18

    Many water quality models have been successfully used worldwide to predict nutrient losses from anthropogenically impacted catchments, but hydrological and nutrient simulations with limited data are difficult considering the transfer of model parameters and complication of model calibration and validation. This study aims: (i) to assess the performance capabilities of a new and relatively more advantageous model, namely, Hydrological Predictions for the Environment (HYPE), that simulates stream flow and nutrient load in agricultural areas by using a multi-site and multi-objective parameter calibration method and (ii) to investigate the temporal and spatial variations of total nitrogen (TN) and total phosphorous (TP) concentrations and loads with crop rotation by using the model for the first time. A parameter estimation tool (PEST) was used to calibrate parameters. Results show that the parameters related to the effective soil porosity were highly sensitive to hydrological modeling. N balance was largely controlled by soil denitrification processes. P balance was influenced by the sedimentation rate and production/decay of P in rivers and lakes. The model reproduced the temporal and spatial variations of discharge and TN/TP relatively well in both calibration (2006-2008) and validation (2009-2010) periods. Among the obtained data, the lowest Nash-Suttclife efficiency of discharge, daily TN load, and daily TP load were 0.74, 0.51, and 0.54, respectively. The seasonal variations of daily TN concentrations in the entire simulation period were insufficient, indicated that crop rotation changed the timing and amount of N output. Monthly TN and TP simulation yields revealed that nutrient outputs were abundant in summer in terms of the corresponding discharge. The area-weighted TN and TP load annual yields in five years showed that nutrient loads were extremely high along Hong and Ru rivers, especially in agricultural lands.

  12. Impacts of Organic Zero Tillage Systems on Crops, Weeds, and Soil Quality

    Directory of Open Access Journals (Sweden)

    Patrick M. Carr

    2013-07-01

    Full Text Available Organic farming has been identified as promoting soil quality even though tillage is used for weed suppression. Adopting zero tillage and other conservation tillage practices can enhance soil quality in cropping systems where synthetic agri-chemicals are relied on for crop nutrition and weed control. Attempts have been made to eliminate tillage completely when growing several field crops organically. Vegetative mulch produced by killed cover crops in organic zero tillage systems can suppress annual weeds, but large amounts are needed for adequate early season weed control. Established perennial weeds are not controlled by cover crop mulch. Integrated weed management strategies that include other cultural as well as biological and mechanical controls have potential and need to be incorporated into organic zero tillage research efforts. Market crop performance in organic zero tillage systems has been mixed because of weed, nutrient cycling, and other problems that still must be solved. Soil quality benefits have been demonstrated in comparisons between organic conservation tillage and inversion tillage systems, but studies that include zero tillage treatments are lacking. Research is needed which identifies agronomic strategies for optimum market crop performance, acceptable levels of weed suppression, and soil quality benefits following adoption of organic zero tillage.

  13. Improving soil microbiology under rice-wheat crop rotation in Indo-Gangetic Plains by optimized resource management.

    Science.gov (United States)

    Sharma, P; Singh, G; Sarkar, Sushil K; Singh, Rana P

    2015-03-01

    The resource-intensive agriculture involving use of chemical fertilizers, irrigation, and tillage practices is a major cause of soil, water, and air pollution. This study was conducted to determine whether integrated use of nutrient, water, and tillage (reduced) can be manipulated to improve the population of plant growth promoting rhizobacteria (Azotobacter, Bacillus, and Pseudomonas) to enhance soil fertility and yield. The study was conducted in the Indo-Gangetic plain (IGP) region of India, where resource-intensive agriculture is practiced. Various combinations of chemical (urea) and organic fertilizers (farmyard manure (FYM), biofertilizer, and green manure) were used on replicated field plots for all the experiments. The effect of integrated resource management (IRM) on activities of Azotobacter, Bacillus, and Pseudomonas and its relation to the yields of rice and wheat crops in subtropical soils of IGP region were also observed. The increased population of all the three microbes, namely, Azotobacter (5.01-7.74 %), Bacillus (3.37-6.79 %), and Pseudomonas (5.21-7.09 %), was observed due to improved structure and increased organic matter in the soil. Similarly, kernel number and 1000 kernel weight were found increased with sole organic N source, three irrigations, and conservation tillage. Thus, it was found that the IRM practices affect the environment positively by increasing the population of beneficial soil microbes and crop yield as compared to high-input agriculture (conventional practices).

  14. Identification of technology options for reducing nitrogen pollution in cropping systems of Pujiang

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    This work analyses the potential role of nitrogen pollution technology of crop systems of Pujiang, County in Eastern China's Zhejiang Province, rice and vegetables are important cropping systems. We used a case study approach involving comparison of farmer practices and improved technologies. This approach allows assessing the impact of technology on pollution, is forward looking, and can yield information on the potential of on-the-shelf technology and provide opportunities for technology development. The approach particularly suits newly developed rice technologies with large potential of reducing nitrogen pollution and for future rice and vegetables technologies. The results showed that substantial reductions in nitrogen pollution are feasible for both types of crops.

  15. Information Collection System of Crop Growth Environment Based on the Internet of Things

    Institute of Scientific and Technical Information of China (English)

    Hua; YU; Guangyu; ZHANG; Ningbo; LU

    2013-01-01

    Based on the technology of Internet of things, for the issues of large amount data acquisition and difficult real time transport in the data acquisition of crop growth environment, this paper designs one information collection system for crop growth environment. Utilizing the range free location mechanism which defines the node position and GEAR routing mechanism give solutions to the problems of node location, routing protocol applications and so on. This system can realize accurate and automatic real time collection, aggregation and transmission of crop growth environment information, and can achieve the automation of agricultural production, to the maximum extent.

  16. Combining Ridge with No-Tillage in Lowland Rice-Based Cropping System:Long-Term Effect on Soil and Rice Yield

    Institute of Scientific and Technical Information of China (English)

    JIANG Xian-Jun; and XIE De-Ti

    2009-01-01

    A tillage method of combining ridge with no-tillage (RNT) was employed in lowland rice-based cropping system to study the long-term effects of RNT on soil profile pattern,soil water stable aggregate distribution,nutrients stratification and yields of rice and post-rice crops.After flooded paddy field (FPF) was practiced with RNT for a long time,soil profile changed from G to A-P-G,and horizon G was shifted to a deeper position in the profile.Also the proportion of macroaggregate (> 2 mm) increased,whereas the proportion of silt and clay (< 0.053 mm) decreased under RNT,indicating a better soil structure that will prevent erosion.RNT helped to control leaching and significantly improved total N,P,K and organic matter in soil.The highest crop yields were found under RNT system every year,and total crop yields were higher under conventional paddy-upland rotation tillage (CR) than under FPF,except in 2003 and 2006 when serious drought occurred.RNT was proven to be a better tillage method for lowland rice-based cropping system.

  17. Biomass storage, decision support systems, and expert systems in crop production and processing

    Energy Technology Data Exchange (ETDEWEB)

    Smith, R.D.

    1985-01-01

    Agricultural production depends on obtaining and efficiently using the necessary resources. Producers must have access to information that will allow them to select among alternative resource inputs and farming practices. This dissertation covers research into the storage of alternative biomass energy crops and the progression into developing integrated, interactive computer based information systems to support agricultural decisions. Biomass could be a significant source of energy and industrial feedstocks. Storing moist biomass between harvest and conversion can lead to degradation and loss of the material. Data on the storage characteristics of corn cobs and corn silage was obtained over two seasons. The results of studies on corn cob storage in outside piles indicated that up to 33% of the available energy and 43% of the available pentosans were lost during 18 months storage. Studies of corn silage preservation showed that 0.5% sulfur dioxide effectively reduced losses of water soluble sugars. The storage research indicated that integrated biomass energy systems with the conversion of silages to ethanol and utilizing crop residues for heat are feasible. The development of decision support systems (DDS) and expert systems (ES) offers great potential for effective transfer of technology from researchers to farmers. A crop planning DSS was constructed on an integrated spreadsheet framework with interactive screen inputs and numerical and graphical outputs.

  18. Nutrient cycling in a cropping system with potato, spring wheat, sugar beet, oats and nitrogen catch crops. II. Effect of catch crops on nitrate leaching in autumn and winter

    NARCIS (Netherlands)

    Vos, J.; Putten, van der P.E.L.

    2004-01-01

    The Nitrate Directive of the European Union (EU) forces agriculture to reduce nitrate emission. The current study addressed nitrate emission and nitrate-N concentrations in leachate from cropping systems with and without the cultivation of catch crops (winter rye: Secale cereale L. and forage rape:

  19. Energy balance in rainfed herbaceous crops in a semiarid environment for a 15-year experiment. 1. Impact of farming systems

    Science.gov (United States)

    Moreno, M. M.; Moreno, C.; Lacasta, C.; Tarquis, A. M.; Meco, R.

    2012-04-01

    During the last years, agricultural practices have led to increase yields by means of the massive consumption on non-renewable fossil energy. However, the viability of a production system does not depend solely on crop yield, but also on its efficiency in the use of available resources. This work is part of a larger study assessing the effects of three farming systems (conventional, conservation with zero tillage, and organic) and four barley-based crop rotations (barley monoculture and in rotation with vetch, sunflower and fallow) on the energy balance of crop production under the semi-arid conditions over a 15 year period. However, the present work is focused on the farming system effect, so crop rotations and years are averaged. Experiments were conducted at "La Higueruela" Experimental Farm (4°26' W, 40°04' N, altitude 450 m) (Spanish National Research Council, Santa Olalla, Toledo, central Spain). The climate is semi-arid Mediterranean, with an average seasonal rainfall of 480 mm irregularly distributed and a 4-month summer drought period. Conventional farming included the use of moldboard plow for tillage, chemical fertilizers and herbicides. Conservation farming was developed with zero tillage, direct sowing and chemical fertilizers and herbicides. Organic farming included the use of cultivator and no chemical fertilizers or herbicides. The energy balance method used required the identification and quantification of all the inputs and outputs implied, and the conversion to energy values by corresponding coefficients. The parameters considered were (i) energy inputs (EI) (diesel, machines, fertilizers, herbicides, seeds) (ii) energy outputs (EO) (energy in the harvested biomass), (iii) net energy produced (NE) (EI - EO), (iv) the energy output/input ratio (O/I), and (v) energy productivity (EP) (Crop yield/EI). EI was 3.0 and 3.5 times higher in conservation (10.4 GJ ha-1 year-1) and conventional (11.7 GJ ha-1 year-1) than in organic farming (3.41 GJ ha-1

  20. Nitrogen source effects on nitrous oxide emissions from irrigated cropping systems in Colorado. American Chemical Society Symposium Series

    Science.gov (United States)

    Nitrogen (N) fertilization is essential in most irrigated cropping systems to optimize crop yields and economic returns. Application of inorganic N fertilizers to these cropping systems generally results in increased nitrous oxide (N2O-N) emissions. Nitrous oxide emissions resulting from the appli...

  1. Crop monitoring & yield forecasting system based on Synthetic Aperture Radar (SAR) and process-based crop growth model: Development and validation in South and South East Asian Countries

    Science.gov (United States)

    Setiyono, T. D.

    2014-12-01

    Accurate and timely information on rice crop growth and yield helps governments and other stakeholders adapting their economic policies and enables relief organizations to better anticipate and coordinate relief efforts in the wake of a natural catastrophe. Such delivery of rice growth and yield information is made possible by regular earth observation using space-born Synthetic Aperture Radar (SAR) technology combined with crop modeling approach to estimate yield. Radar-based remote sensing is capable of observing rice vegetation growth irrespective of cloud coverage, an important feature given that in incidences of flooding the sky is often cloud-covered. The system allows rapid damage assessment over the area of interest. Rice yield monitoring is based on a crop growth simulation and SAR-derived key information, particularly start of season and leaf growth rate. Results from pilot study sites in South and South East Asian countries suggest that incorporation of SAR data into crop model improves yield estimation for actual yields. Remote-sensing data assimilation into crop model effectively capture responses of rice crops to environmental conditions over large spatial coverage, which otherwise is practically impossible to achieve. Such improvement of actual yield estimates offers practical application such as in a crop insurance program. Process-based crop simulation model is used in the system to ensure climate information is adequately captured and to enable mid-season yield forecast.

  2. Modeling nitrogen and water management effects in a wheat-maize double-cropping system.

    Science.gov (United States)

    Fang, Q; Ma, L; Yu, Q; Malone, R W; Saseendran, S A; Ahuja, L R

    2008-01-01

    Excessive N and water use in agriculture causes environmental degradation and can potentially jeopardize the sustainability of the system. A field study was conducted from 2000 to 2002 to study the effects of four N treatments (0, 100, 200, and 300 kg N ha(-1) per crop) on a wheat (Triticum aestivum L.) and maize (Zea mays L.) double cropping system under 70 +/- 15% field capacity in the North China Plain (NCP). The root zone water quality model (RZWQM), with the crop estimation through resource and environment synthesis (CERES) plant growth modules incorporated, was evaluated for its simulation of crop production, soil water, and N leaching in the double cropping system. Soil water content, biomass, and grain yield were better simulated with normalized root mean square errors (NRMSE, RMSE divided by mean observed value) from 0.11 to 0.15 than soil NO(3)-N and plant N uptake that had NRMSE from 0.19 to 0.43 across these treatments. The long-term simulation with historical weather data showed that, at 200 kg N ha(-1) per crop application rate, auto-irrigation triggered at 50% of the field capacity and recharged to 60% field capacity in the 0- to 50-cm soil profile were adequate for obtaining acceptable yield levels in this intensified double cropping system. Results also showed potential savings of more than 30% of the current N application rates per crop from 300 to 200 kg N ha(-1), which could reduce about 60% of the N leaching without compromising crop yields.

  3. Integrated crop-livestock systems − a key to sustainable intensification in Africa

    Directory of Open Access Journals (Sweden)

    A.J. Duncan

    2013-12-01

    Full Text Available Mixed crop-livestock systems provide livelihoods for a billion people and produce half the world’s cereal and around a third of its beef and milk. Market orientation and strong and growing demand for food provide powerful incentives for sustainable intensification of both crop and livestock enterprises in smallholders’ mixed systems in Africa. Better exploitation of the mutually reinforcing nature of crop and livestock systems can contribute to a positive, inclusive growth trajectory that is both ecologically and economically sustainable. In mixed systems, livestock intensification is often neglected relative to crops, yet livestock can make a positive contribution to raising productivity of the entire farming system. Similarly, intensification of crop production can pay dividends for livestock and enhance natural resource management, especially through increased biomass availability. Intensification and improved efficiency of livestock production mean less greenhouse gases per unit of milk and more milk per unit of water. This paper argues that the opportunities and challenges justify greater investment in research for development to identify exactly where and how ‘win-win’ outcomes can be achieved and what incentives, policies, technologies and other features of the enabling environment are needed to enable sustainable, integrated and productive mixed crop-livestock systems.

  4. Flow electrification characteristics of transformer oil by rotating electrode systems

    Energy Technology Data Exchange (ETDEWEB)

    Jagadish, R.; Poovamma, P.K. [Central Power Research Inst., Bangalore (India)

    1995-07-01

    Flow electrification has been found to be the principal cause of a number of failures of forced oil cooled power transformers. Flow charging characteristics of oil/cellulose system with factors like electrode configuration, electrode material, presence of Benzotriazole (BTA), metallic contaminants and Copper coils were investigated for paraffinic oil by employing rotating electrode system. A few hydrodynamic parameters viz. Reynolds number, boundary layer thickness and friction factor were correlated with flow charging characteristics of oil for varying temperatures and concentrations of BTA. With lower concentrations of BTA in oil viz. 10 ppm and 25 ppm a marginal reduction in flow charging of oil was noticed, but about 40% reduction was observed with 150 ppm of BTA. A significant reduction in the flow charging characteristics of untreated and BTA treated oils was also observed in the presence of Copper coils and metallic particle contaminants.

  5. Variant Computer Aided Process Planning System for Rotational Parts

    Institute of Scientific and Technical Information of China (English)

    AHMED Hassan; YAO Zhen-qiang; CAI Jian-guo

    2005-01-01

    The amount of material must be removed away to produce the final product should minimize, excess stock will increase not only the material cost, but also processing cost, fixture cost, tooling cost, and increases machine cycle times.Noticing in recent years that the world is running out of mineral resources, and the price of engineering materials will continually rise in the future, the percentage of the cost of manufactured part that is due to the cost of materials is also rising. This paper proposed a variant CAPP system for rotational parts based on the concept of group technology,this system accepts part features characteristics code number as an input and provides operation details for manufacturing route with the suitable primary processes required to produce the blank work piece as an output.

  6. SVD for imaging systems with discrete rotational symmetry.

    Science.gov (United States)

    Clarkson, Eric; Palit, Robin; Kupinski, Matthew A

    2010-11-22

    The singular value decomposition (SVD) of an imaging system is a computationally intensive calculation for tomographic imaging systems due to the large dimensionality of the system matrix. The computation often involves memory and storage requirements beyond those available to most end users. We have developed a method that reduces the dimension of the SVD problem towards the goal of making the calculation tractable for a standard desktop computer. In the presence of discrete rotational symmetry we show that the dimension of the SVD computation can be reduced by a factor equal to the number of collection angles for the tomographic system. In this paper we present the mathematical theory for our method, validate that our method produces the same results as standard SVD analysis, and finally apply our technique to the sensitivity matrix for a clinical CT system. The ability to compute the full singular value spectra and singular vectors will augment future work in system characterization, image-quality assessment and reconstruction techniques for tomographic imaging systems.

  7. Propagation of angular errors in two-axis rotation systems

    Science.gov (United States)

    Torrington, Geoffrey K.

    2003-10-01

    Two-Axis Rotation Systems, or "goniometers," are used in diverse applications including telescope pointing, automotive headlamp testing, and display testing. There are three basic configurations in which a goniometer can be built depending on the orientation and order of the stages. Each configuration has a governing set of equations which convert motion between the system "native" coordinates to other base systems, such as direction cosines, optical field angles, or spherical-polar coordinates. In their simplest form, these equations neglect errors present in real systems. In this paper, a statistical treatment of error source propagation is developed which uses only tolerance data, such as can be obtained from the system mechanical drawings prior to fabrication. It is shown that certain error sources are fully correctable, partially correctable, or uncorrectable, depending upon the goniometer configuration and zeroing technique. The system error budget can be described by a root-sum-of-squares technique with weighting factors describing the sensitivity of each error source. This paper tabulates weighting factors at 67% (k=1) and 95% (k=2) confidence for various levels of maximum travel for each goniometer configuration. As a practical example, this paper works through an error budget used for the procurement of a system at Sandia National Laboratories.

  8. Influence of Previous Crop on Durum Wheat Yield and Yield Stability in a Long-term Experiment

    Directory of Open Access Journals (Sweden)

    Anna Maria Stellacci

    2011-02-01

    Full Text Available Long-term experiments are leading indicators of sustainability and serve as an early warning system to detect problems that may compromise future productivity. So the stability of yield is an important parameter to be considered when judging the value of a cropping system relative to others. In a long-term rotation experiment set up in 1972 the influence of different crop sequences on the yields and on yield stability of durum wheat (Triticum durum Desf. was studied. The complete field experiment is a split-split plot in a randomized complete block design with two replications; the whole experiment considers three crop sequences: 1 three-year crop rotation: sugar-beet, wheat + catch crop, wheat; 2 one-year crop rotation: wheat + catch crop; 3 wheat continuous crop; the split treatments are two different crop residue managements; the split-split plot treatments are 18 different fertilization formulas. Each phase of every crop rotation occurred every year. In this paper only one crop residue management and only one fertilization treatment have been analized. Wheat crops in different rotations are coded as follows: F1: wheat after sugar-beet in three-year crop rotation; F2: wheat after wheat in three-year crop rotation; Fc+i: wheat in wheat + catch crop rotation; Fc: continuous wheat. The following two variables were analysed: grain yield and hectolitre weight. Repeated measures analyses of variance and stability analyses have been perfomed for the two variables. The stability analysis was conducted using: three variance methods, namely the coefficient of variability of Francis and Kannenberg, the ecovalence index of Wricke and the stability variance index of Shukla; the regression method of Eberhart and Russell; a method, proposed by Piepho, that computes the probability of one system outperforming another system. It has turned out that each of the stability methods used has enriched of information the simple variance analysis. The Piepho

  9. Determination of critical micelle concentration with the rotating sample system.

    Science.gov (United States)

    Kao, Linus T; Shetty, Gautam N; Gratzl, Miklós

    2008-12-01

    A novel experimental approach using the rotating sample system (RSS) is proposed here for the determination of the critical micelle concentration (CMC) of surfactants. The RSS has been conceived in our laboratory as a convection platform for physicochemical studies and analyses in microliter-sized sample drops. The scheme allows for vigorous rotation of the drop despite its small size through efficient air-liquid mechanical coupling. Thus, changes in surface properties of aqueous samples result in corresponding modulation of the hydrodynamic performance of the RSS, which can be utilized to investigate interfacial phenomena. In this work, we demonstrate that the RSS can be used to study the effects of surfactants on the surface and in the bulk of very small samples with hydrodynamic electrochemistry. Potassium ferrocyanide is employed here with cyclic voltammetry to probe the air-water interface of solutions containing Triton X-100. The CMC of this surfactant determined using this approach is 140 ppm, which agrees well with reported values obtained with conventional methods in much larger samples. The results also demonstrate that besides the CMC, variations in bulk rheological properties can also be investigated in very small specimens using the RSS with a simple method.

  10. Prediction of Earth rotation parameters by fuzzy inference systems

    Science.gov (United States)

    Akyilmaz, O.; Kutterer, H.

    2004-09-01

    The short-term prediction of Earth rotation parameters (ERP) (length-of-day and polar motion) is studied up to 10 days by means of ANFIS (adaptive network based fuzzy inference system). The prediction is then extended to 40 days into the future by using the formerly predicted values as input data. The ERP C04 time series with daily values from the International Earth Rotation Service (IERS) serve as the data base. Well-known effects in the ERP series, such as the impact of the tides of the solid Earth and the oceans or seasonal variations of the atmosphere, were removed a priori from the C04 series. The residual series were used for both training and validation of the network. Different network architectures are discussed and compared in order to optimize the network solution. The results of the prediction are analyzed and compared with those of other methods. Short-term ERP values predicted by ANFIS show root-mean-square errors which are equal to or even lower than those from the other considered methods. The presented method is easy to use.

  11. Development of a growth model-based decision support system for crop management

    Institute of Scientific and Technical Information of China (English)

    ZHU Yan; TANG Liang; LIU Xiaojun; TIAN Yongchao; YAO Xia; CAO Weixing

    2007-01-01

    A growth model-based decision support system for crop management (GMDSSCM) was developed,which integrates process-based models of four different crops-wheat,rice,rape and cotton-and realized decision support function,thus facilitating the simulation and application of the crop models for different purposes.The individual models include six sub models for simulating phase development,organ formation,biomass production,yield and quality formation,soil-crop water relations and nutrient (N,P,K)balance.The implemented system can be used for evaluating individual and comprehensive management strategies based on the results of crop growth simulation under various environments and different genotypes.A stand-alone edition (GMDSSCMA) was established on VC++ and VB platforms by adopting the characteristics of object-oriented and component-based software and with the effective integration and coupling of the growth prediction and decision-making functions.A web-based system (GMDSSCMw) was then further developed on the .net platform using C# language.These GMDSSCM systems have realized dynamic prediction of crop growth and decision making on cultural management,and thus should be helpful for the construction and application of informational and digital fanning system.

  12. Energy crops for biogas plants. Brandenburg; Energiepflanzen fuer Biogasanlagen. Brandenburg

    Energy Technology Data Exchange (ETDEWEB)

    Adam, L.; Barthelmes, G.; Biertuempfel, A. (and others)

    2012-06-15

    In the brochure under consideration, the Agency for Renewable Resources (Guelzen-Pruezen, Federal Republic of Germany) reported on recommendations on alternative cropping systems for energy crop rotations in order to achieve high yields in combination with high diversity, risk spreading and sustainability. In particular, the natural site conditions in the Federal State of Brandenburg (Federal Republic of Germany) are determined.

  13. Crop yield network and its response to changes in climate system

    Science.gov (United States)

    Yokozawa, M.

    2013-12-01

    Crop failure (reduction in crop yield) due to extreme weather and climate change could lead to unstable food supply, reflecting the recent globalization in world agricultural production. Specifically, in several major production countries producing large amount of main cereal crops, wheat, maize, soybean and rice, abrupt crop failures in wide area are significantly serious for world food supply system. We examined the simultaneous changes in crop yield in USA, China and Brazil, in terms of the changes in climate system such as El Nino, La nina and so on. In this study, we defined a crop yield networks, which represent the correlation between yearly changes in crop yields and climate resources during the crop growing season in two regions. The climate resources during the crop growing season represents here the average temperature and the accumulated precipitation during the crop growing season of a target crop. As climate data, we used a reanalysis climate data JRA-25 (Japan Meteorological Agency). The yearly changes in crop yields are based on a gridded crop productivity database with a resolution of 1.125 degree in latitude/longitude (Iizumi et al. 2013). It is constructed from the agriculture statistics issued by local administrative bureau in each country, which covers the period during 1982 to 2006 (25 years). For the regions being lack of data, the data was interpolated referring to NPP values estimated by satellite data. Crop yield network is constructed as follows: (1) let DY(i,y) be negative difference in crop yield of year y from the trend yield at grid i; (2) define the correlation of the differences Cij(y) = DY(i, y) DY(j, y); (3) if Cij(y) > Q, then grids i and j are mutually linked for a threshold value Q. Links between grids make a crop yield network. It is here noted that only negative differences are taken into account because we focused on the lean year cases (i.e. yields of both grids were lower than those in the long-term trend). The arrays of

  14. A brief survey of computerized expert systems for crop protection being used in India

    Institute of Scientific and Technical Information of China (English)

    Pinaki Chakraborty; Dilip Kumar Chakrabarti

    2008-01-01

    In the recent years, a plethora of computerized expert systems has been developed for various sectors of agriculture in India. The availability of low-cost computers, agricultural knowledge and information technology professionals are the principal reasons for the development of so many agricultural expert systems. Among all agricultural expert systems, the expert systems for crop protection need special mention. These expert systems are meant to be used by farmers and other persons without much experience of using computers. Hence, special care must be taken while developing them. The current paper develops a taxonomy for the expert systems for crop protection and briefly discusses four such expert systems for crop protection being used in India.

  15. Comparative study of rhizobacterial communities in pepper greenhouses and examination of the effects of salt accumulation under different cropping systems.

    Science.gov (United States)

    Hahm, Mi-Seon; Son, Jin-Soo; Kim, Byung-Soo; Ghim, Sa-Youl

    2017-03-01

    This study compared rhizobacterial communities in pepper greenhouses under a paddy-upland (rice-pepper) rotational system (PURS) and a monoculture repeated cropping system (RCS) and examined adverse effects of high salinity on soil properties. The following soil properties were analyzed: electrical conductivity (EC), pH, concentration of four cations (Na, Ca, Mg, and K), total nitrogen, and organic matter content. Rhizobacterial communities were analyzed using culture-based and culture-independent (pyrosequencing) methods. In addition, all culturable bacteria isolated from each soil sample were tested for traits related to plant growth promotion. The EC of rhizospheric soils was 5.32-5.54 dS/m for the RCS and 2.05-2.19 dS/m for the PURS. The culture-based method indicated that the bacterial communities and bacterial characteristics were significantly more diverse in the PURS soil than in the RCS soil. The pyrosequencing data also indicated that the richness and diversity of bacterial communities were greater in the PURS soil. Proteobacteria was the most abundant phylum in soil samples under both cropping systems. However, Firmicutes and Gemmatimonadetes were more prevalent in the RCS soil, while the PURS soil contained a greater number of Chloroflexi. Spearman's correlation coefficients showed that soil EC was significantly positively correlated with the abundance of Firmicutes and Gemmatimonadetes and negatively correlated with the abundance of Acidobacteria, Chloroflexi, and Deltaproteobacteria. This is the first study on the rhizobacterial communities in pepper greenhouses under two different cropping systems using both culture- and pyrosequencing-based methods.

  16. Nine-year results on maize and processing tomato cultivation in an organic and in a conventional low input cropping system

    Directory of Open Access Journals (Sweden)

    Michela Farneselli

    2013-02-01

    Full Text Available Nine-year results on yields and apparent balances of organic matter and nitrogen (N are reported for maize and processing tomato cultivated in a long term comparison trial between an organic and a conventional low-input system in Central Italy. In every year, above ground biomass and N accumulation of each cash crop and green manure, including weeds, and the partitioning between marketable yield and crop residues were determined. Apparent dry matter and nitrogen balances were calculated at the end of each crop cycle by taking into account the amounts of dry matter and ex-novo N supplied to the system as green manure legume Ndfa (i.e. an estimate of N derived from the atmosphere via symbiotic fixation and fertilizers, and those removed with marketable yield. Processing tomato complied with organic cultivation better than maize. As compared to the conventional crop cultivation, organic tomato provided similar yields, used supplied N more efficiently and left lower residual N after harvest, with lower related risks of pollution. Organic maize yielded less than conventional one. The main limitation for organic maize was the low N availability during initial growth phases, due to either low N supply or low rate of N release from incorporated green manure biomass. In both organic and conventional cultivation the system sustainability could be improved by an appropriate crop rotation: wheat in fall winter likely prevented leaching loss of mineral N in both systems; green manure crops in the organic system allowed to either trap and recycle soil mineral N or supply ex novo legume Ndfa to the soil, with benefits in mitigation of N pollution and improvement in self-sufficiency of the system.

  17. Testing of a new morphing trailing edge flap system on a novel outdoor rotating test rig

    DEFF Research Database (Denmark)

    Aagaard Madsen, Helge; Barlas, Athanasios; Løgstrup Andersen, Tom

    2015-01-01

    manufacturing and application. To narrow the gap between wind tunnel testing and full scale prototype testing we developed the rotating test rig. The overall objectives with the rotating test rig are: 1) to test the flap system in a realistic rotating environment with a realistic g-loading; 2) to measure...

  18. Systems and assemblies for transferring high power laser energy through a rotating junction

    Energy Technology Data Exchange (ETDEWEB)

    Norton, Ryan J.; McKay, Ryan P.; Fraze, Jason D.; Rinzler, Charles C.; Grubb, Daryl L.; Faircloth, Brian O.; Zediker, Mark S.

    2016-01-26

    There are provided high power laser devices and systems for transmitting a high power laser beam across a rotating assembly, including optical slip rings and optical rotational coupling assemblies. These devices can transmit the laser beam through the rotation zone in free space or within a fiber.

  19. Census parcels cropping system classification from multitemporal remote imagery: a proposed universal methodology.

    Science.gov (United States)

    García-Torres, Luis; Caballero-Novella, Juan J; Gómez-Candón, David; Peña, José Manuel

    2015-01-01

    A procedure named CROPCLASS was developed to semi-automate census parcel crop assessment in any agricultural area using multitemporal remote images. For each area, CROPCLASS consists of a) a definition of census parcels through vector files in all of the images; b) the extraction of spectral bands (SB) and key vegetation index (VI) average values for each parcel and image; c) the conformation of a matrix data (MD) of the extracted information; d) the classification of MD decision trees (DT) and Structured Query Language (SQL) crop predictive model definition also based on preliminary land-use ground-truth work in a reduced number of parcels; and e) the implementation of predictive models to classify unidentified parcels land uses. The software named CROPCLASS-2.0 was developed to semi-automatically perform the described procedure in an economically feasible manner. The CROPCLASS methodology was validated using seven GeoEye-1 satellite images that were taken over the LaVentilla area (Southern Spain) from April to October 2010 at 3- to 4-week intervals. The studied region was visited every 3 weeks, identifying 12 crops and others land uses in 311 parcels. The DT training models for each cropping system were assessed at a 95% to 100% overall accuracy (OA) for each crop within its corresponding cropping systems. The DT training models that were used to directly identify the individual crops were assessed with 80.7% OA, with a user accuracy of approximately 80% or higher for most crops. Generally, the DT model accuracy was similar using the seven images that were taken at approximately one-month intervals or a set of three images that were taken during early spring, summer and autumn, or set of two images that were taken at about 2 to 3 months interval. The classification of the unidentified parcels for the individual crops was achieved with an OA of 79.5%.

  20. Mycorrhizal population on various cropping systems on sandy soil in dryland area of North Lombok, Indonesia

    Directory of Open Access Journals (Sweden)

    WAHYU ASTIKO

    2016-01-01

    Full Text Available Abstract. Astiko W, Fauzi MT, Sukartono. 2016. Mycorrhizal population on various cropping systems on sandy soil in dryland area of North Lombok, Indonesia. Nusantara Bioscience 8: 66-70. Inoculation of arbuscular mycorrhizal fungi (AMF on maize in sandy soil is expected to have positive implications for the improvement of AMF population and nutrient uptake. However, how many increases in the AMF population and nutrient uptake in the second cycle of a certain cropping system commonly cultivated by the farmers after growing their corn crop have not been examined. Since different cropping systems would indicate different increases in the populations of AMF and nutrient uptake. This study aimed to determine the population AMF and nutrient uptake on the second cropping cycle of corn-based cropping systems which utilized indigenous mycorrhizal fungi on sandy soil in dryland area of North Lombok, West Nusa Tenggara, Indonesia. For that purpose, an experiment was conducted at the Akar-Akar Village in Bayan Sub-district of North Lombok, designed according to the Randomized Complete Block Design, with four replications and six treatments of cropping cycles (P0 = corn-soybean as a control, in which the corn plants were not inoculated with AMF; P1 = corn-soybean, P2 = corn-peanut, P3 = corn-upland rice, P4 = corn-sorghum, and P5 = corn-corn, in which the first cycle corn plants were inoculated with AMF. The results indicated that the mycorrhizal populations (spore number and infection percentage were highest in the second cycle sorghum, achieving 335% and 226% respectively, which were significantly higher than those in the control. Increased uptake of N, P, K and Ca the sorghum plants at 60 DAS of the second cropping cycle reached 200%; 550%; 120% and 490% higher than in the control. The soil used in this experiment is rough-textured (sandy loam, so it is relatively low in water holding capacity and high porosity.

  1. A GPS Backpack System for Mapping Soil and Crop Parameters in Agricultural Fields

    Science.gov (United States)

    Stafford, J. V.; Lebars, J. M.

    Farmers are having to gather increasing amounts of data on their soils and crops. Precision agriculture metre-by-metre is based on a knowledge of the spatial variation of soil and crop parameters across a field. The data has to be spatially located and GPS is an effective way of doing this. A backpack data logging system with GPS position tagging is described which has been designed to aid a fanner in the manual collection of data.

  2. Understanding cropping systems in the semi-arid environments of Zimbabwe: options for soil fertility management

    OpenAIRE

    Ncube, B.

    2007-01-01

    African smallholder farmers face perennial food shortages due to low crop yields. The major cause of poor crop yields is soil fertility decline. The diversity of sites and soils between African farming systems isgreat,therefore strategies to solve soil fertility problems should suit the opportunities and problems encountered in the different climatic regions. This thesis characterizes the semi-arid regions of south-western Zimbabwe and explores some of the strategies that can be used to provi...

  3. Molecular and systems approaches towards drought-tolerant canola crops.

    Science.gov (United States)

    Zhu, Mengmeng; Monroe, J Grey; Suhail, Yasir; Villiers, Florent; Mullen, Jack; Pater, Dianne; Hauser, Felix; Jeon, Byeong Wook; Bader, Joel S; Kwak, June M; Schroeder, Julian I; McKay, John K; Assmann, Sarah M

    2016-06-01

    1169 I. 1170 II. 1170 III. 1172 IV. 1176 V. 1181 VI. 1182 1183 References 1183 SUMMARY: Modern agriculture is facing multiple challenges including the necessity for a substantial increase in production to meet the needs of a burgeoning human population. Water shortage is a deleterious consequence of both population growth and climate change and is one of the most severe factors limiting global crop productivity. Brassica species, particularly canola varieties, are cultivated worldwide for edible oil, animal feed, and biodiesel, and suffer dramatic yield loss upon drought stress. The recent release of the Brassica napus genome supplies essential genetic information to facilitate identification of drought-related genes and provides new information for agricultural improvement in this species. Here we summarize current knowledge regarding drought responses of canola, including physiological and -omics effects of drought. We further discuss knowledge gained through translational biology based on discoveries in the closely related reference species Arabidopsis thaliana and through genetic strategies such as genome-wide association studies and analysis of natural variation. Knowledge of drought tolerance/resistance responses in canola together with research outcomes arising from new technologies and methodologies will inform novel strategies for improvement of drought tolerance and yield in this and other important crop species.

  4. Effects of crop species richness on pest-natural enemy systems based on an experimental model system using a microlandscape.

    Science.gov (United States)

    Zhao, ZiHua; Shi, PeiJian; Men, XingYuan; Ouyang, Fang; Ge, Feng

    2013-08-01

    The relationship between crop richness and predator-prey interactions as they relate to pest-natural enemy systems is a very important topic in ecology and greatly affects biological control services. The effects of crop arrangement on predator-prey interactions have received much attention as the basis for pest population management. To explore the internal mechanisms and factors driving the relationship between crop richness and pest population management, we designed an experimental model system of a microlandscape that included 50 plots and five treatments. Each treatment had 10 repetitions in each year from 2007 to 2010. The results showed that the biomass of pests and their natural enemies increased with increasing crop biomass and decreased with decreasing crop biomass; however, the effects of plant biomass on the pest and natural enemy biomass were not significant. The relationship between adjacent trophic levels was significant (such as pests and their natural enemies or crops and pests), whereas non-adjacent trophic levels (crops and natural enemies) did not significantly interact with each other. The ratio of natural enemy/pest biomass was the highest in the areas of four crop species that had the best biological control service. Having either low or high crop species richness did not enhance the pest population management service and lead to loss of biological control. Although the resource concentration hypothesis was not well supported by our results, high crop species richness could suppress the pest population, indicating that crop species richness could enhance biological control services. These results could be applied in habitat management aimed at biological control, provide the theoretical basis for agricultural landscape design, and also suggest new methods for integrated pest management.

  5. Effect of tillage practices on soil properties and crop productivity in wheat-mungbean-rice cropping system under subtropical climatic conditions.

    Science.gov (United States)

    Alam, Md Khairul; Islam, Md Monirul; Salahin, Nazmus; Hasanuzzaman, Mirza

    2014-01-01

    This study was conducted to know cropping cycles required to improve OM status in soil and to investigate the effects of medium-term tillage practices on soil properties and crop yields in Grey Terrace soil of Bangladesh under wheat-mungbean-T. aman cropping system. Four different tillage practices, namely, zero tillage (ZT), minimum tillage (MT), conventional tillage (CT), and deep tillage (DT), were studied in a randomized complete block (RCB) design with four replications. Tillage practices showed positive effects on soil properties and crop yields. After four cropping cycles, the highest OM accumulation, the maximum root mass density (0-15 cm soil depth), and the improved physical and chemical properties were recorded in the conservational tillage practices. Bulk and particle densities were decreased due to tillage practices, having the highest reduction of these properties and the highest increase of porosity and field capacity in zero tillage. The highest total N, P, K, and S in their available forms were recorded in zero tillage. All tillage practices showed similar yield after four years of cropping cycles. Therefore, we conclude that zero tillage with 20% residue retention was found to be suitable for soil health and achieving optimum yield under the cropping system in Grey Terrace soil (Aeric Albaquept).

  6. Algebraic structure and Poisson integrals of a rotational relativistic Birkhoff system

    Institute of Scientific and Technical Information of China (English)

    罗绍凯; 陈向炜; 郭永新

    2002-01-01

    We have studied the algebraic structure of the dynamical equations of a rotational relativistic Birkhoff system. It is proven that autonomous and semi-autonomous rotational relativistic Birkhoff equations possess consistent algebraic structure and Lie algebraic structure. In general, non-autonomous rotational relativistic Birkhoff equations possess no algebraic structure, but a type of special non-autonomous rotational relativistic Birkhoff equation possesses consistent algebraic structure and consistent Lie algebraic structure. Then, we obtain the Poisson integrals of the dynamical equations of the rotational relativistic Birkhoff system. Finally, we give an example to illustrate the application of the results.

  7. Substrate Cultivation of Chrysanthemum: Plant performance in 6 cropping systems and the effect of parameters associated with root environment

    NARCIS (Netherlands)

    Guo, X.; Blok, C.

    2010-01-01

    Summary Chrysanthemum is an important greenhouse crop in Holland and is still cultivated in soil. To prevent the emission of nutrients and crop protecting agents, an emission:free cropping system should be developed. This experiment was conducted to that purpose. The objectives of this experiment we

  8. Characteristics of nitrogen balance in open-air and greenhouse vegetable cropping systems of China.

    Science.gov (United States)

    Ti, Chaopu; Luo, Yongxia; Yan, Xiaoyuan

    2015-12-01

    Nitrogen (N) loss from vegetable cropping systems has become a significant environmental issue in China. In this study, estimation of N balances in both open-air and greenhouse vegetable cropping systems in China was established. Results showed that the total N input in open-air and greenhouse vegetable cropping systems in 2010 was 5.44 and 2.60 Tg, respectively. Chemical fertilizer N input in the two cropping systems was 201 kg N ha(-1) per season (open-air) and 478 kg N ha(-1) per season (greenhouse). The N use efficiency (NUE) was 25.9 ± 13.3 and 19.7 ± 9.4% for open-air and greenhouse vegetable cropping systems, respectively, significantly lower than that of maize, wheat, and rice. Approximately 30.6% of total N input was accumulated in soils and 0.8% was lost by ammonia volatilization in greenhouse vegetable system, while N accumulation and ammonia volatilization accounted for 19.1 and 11.1%, respectively, of total N input in open-air vegetable systems.

  9. Effects of contrasting catch crops on nitrogen availability and nitrous oxide emissions in an organic cropping system

    DEFF Research Database (Denmark)

    Li, Xiaoxi; Petersen, Søren O; Sørensen, Peter;

    2015-01-01

    crops. The effect of two catch crop management strategies was also tested: autumn harvest of the catch crop versus incorporation of whole-crop residues by spring ploughing. LBCCs accumulated 59–67 kg N ha−1 in their tops, significantly more than those of the non-LBCC, 32–40 kg N ha−1. Macro...... of catch crops, especially LBCCs, tended to reduce crop yield. The annual N2O emissions were comparable across treatments except for fodder radish, which had the highest N2O emission, and also the highest average yield-scaled N2O emission, at 499 g N2O-N Mg−1 grain. Although the sampling strategy employed...

  10. Research on motor rotational speed measurement in regenerative braking system of electric vehicle

    Science.gov (United States)

    Pan, Chaofeng; Chen, Liao; Chen, Long; Jiang, Haobin; Li, Zhongxing; Wang, Shaohua

    2016-01-01

    Rotational speed signals acquisition and processing techniques are widely used in rotational machinery. In order to realized precise and real-time control of motor drive and regenerative braking process, rotational speed measurement techniques are needed in electric vehicles. Obtaining accurate motor rotational speed signal will contribute to the regenerative braking force control steadily and realized higher energy recovery rate. This paper aims to develop a method that provides instantaneous speed information in the form of motor rotation. It addresses principles of motor rotational speed measurement in the regenerative braking systems of electric vehicle firstly. The paper then presents ideal and actual Hall position sensor signals characteristics, the relation between the motor rotational speed and the Hall position sensor signals is revealed. Finally, Hall position sensor signals conditioning and processing circuit and program for motor rotational speed measurement have been carried out based on measurement error analysis.

  11. Impact of management strategies on the global warming potential at the cropping system level.

    Science.gov (United States)

    Goglio, Pietro; Grant, Brian B; Smith, Ward N; Desjardins, Raymond L; Worth, Devon E; Zentner, Robert; Malhi, Sukhdev S

    2014-08-15

    Estimating the greenhouse gas (GHG) emissions from agricultural systems is important in order to assess the impact of agriculture on climate change. In this study experimental data supplemented with results from a biophysical model (DNDC) were combined with life cycle assessment (LCA) to investigate the impact of management strategies on global warming potential of long-term cropping systems at two locations (Breton and Ellerslie) in Alberta, Canada. The aim was to estimate the difference in global warming potential (GWP) of cropping systems due to N fertilizer reduction and residue removal. Reducing the nitrogen fertilizer rate from 75 to 50 kg N ha(-1) decreased on average the emissions of N2O by 39%, NO by 59% and ammonia volatilisation by 57%. No clear trend for soil CO2 emissions was determined among cropping systems. When evaluated on a per hectare basis, cropping systems with residue removal required 6% more energy and had a little change in GWP. Conversely, when evaluated on the basis of gigajoules of harvestable biomass, residue removal resulted in 28% less energy requirement and 33% lower GWP. Reducing nitrogen fertilizer rate resulted in 18% less GWP on average for both functional units at Breton and 39% less GWP at Ellerslie. Nitrous oxide emissions contributed on average 67% to the overall GWP per ha. This study demonstrated that small changes in N fertilizer have a minimal impact on the productivity of the cropping systems but can still have a substantial environmental impact.

  12. General description and operation of the agro-environmental system: Crop management modeling. [Virginia

    Science.gov (United States)

    Gross, E.; Scott, J. H., Jr.

    1981-01-01

    Input for a data management system to provide farmers with information to improve crop management practices in Virginia requires monitoring of control crops at field stations, crop surveys derived from remotely sensed aircraft data, meteorological data from synchronous satellites, and details of local agricultural conditions. Presently models are under development for determining pest problems, water balance in the soil, stages of plant maturity, and optimum planting date. The status of the Cerospora leafspot model for peanut crop management is considered. Other models under development planned relate to Cylindtocladium Blackrot and Sclerotinia blight of peanuts, cyst nematode (Globerdena solanacearum) of tobacco, and red crown rot of soybeans. A software for program for estimating precipitation and solar radiation on a statewise basis is also being developed.

  13. Carbon Dioxide, Methane, and Nitrous Oxide Emissions from a Rice-Wheat Rotation as Affected by Crop Residue Incorporation and Temperature

    Institute of Scientific and Technical Information of China (English)

    邹建文; 黄耀; 宗良纲; 郑循华; 王跃思

    2004-01-01

    Field measurements were made from June 2001 to May 2002 to evaluate the effect of crop residue application and temperature on CO2, CH4, and N2O emissions within an entire rice-wheat rotation season.Rapeseed cake and wheat straw were incorporated into the soil at a rate of 2.25 t hm-2 when the rice crop was transplanted in June 2001. Compared with the control, the incorporation of rapeseed cake enhanced the emissions of CO2, CH4, and N2O in the rice-growing season by 12.3%, 252.3%, and 17.5%,respectively, while no further effect was held on the emissions of CO2 and N2O in the following wheatgrowing season. The incorporation of wheat straw enhanced the emissions of CO2 and CH4 by 7.1%and 249.6%, respectively, but reduced the N2O emission by 18.8% in the rice-growing season. Significant reductions of 17.8% for the CO2 and of 12.9% for the N2O emission were observed in the following wheatgrowing season. A positive correlation existed between the emissions of N2O and CO2 (R2 = 0.445, n =73, p < 0.001) from the rice-growing season when N2O was emitted. A trade-off relationship between the emissions of CH4 and N2O was found in the rice-growing season. The CH4 emission was significantly correlated with the CO2 emission for the period from rice transplantation to field drainage, but not for the entire rice-growing season. In addition, air temperature was found to regulate the CO2 emissions from the non-waterlogged period over the entire rice-wheat rotation season and the N2O emissions from the nonwaterlogged period of the rice-growing season, which can be quantitatively described by an exponential function. The temperature coefficient (Q10) was then evaluated to be 2.3±0.2 for the CO2 emission and 3.9±0.4 for the N2O emission, respectively.

  14. Efficacy of Fluensulfone in a Tomato–Cucumber Double Cropping System

    Science.gov (United States)

    Morris, Kelly A.; Langston, David B.; Dickson, Donald W.; Davis, Richard F.; Timper, Patricia; Noe, James P.

    2015-01-01

    Vegetable crops in the southeastern United States are commonly grown on plastic mulch with two crop cycles produced on a single mulch application. Field trials were conducted in 2013 and 2014 in two locations to evaluate the efficacy of fluensulfone for controlling Meloidogyne spp. when applied through drip irrigation to cucumber in a tomato–cucumber double-cropping system. In the spring tomato crop, 1,3-dichloropropene (1,3-D), fluensulfone, and a resistant cultivar significantly decreased root galling by 91%, 73%, and 97%, respectively, compared to the untreated control. Tomato plots from the spring were divided into split plots for the fall where the main plots were the spring treatment and the subplots were cucumber either treated with fluensulfone (3.0 kg a.i./ha. via drip irrigation) or left untreated. The fall application of fluensulfone improved cucumber vigor and reduced gall ratings compared to untreated subplots. Fluensulfone reduced damage from root-knot nematodes when applied to the first crop as well as provided additional protection to the second crop when it was applied through a drip system. PMID:26941459

  15. Water Renew systems: wastewater polishing using renewable energy crops.

    Science.gov (United States)

    Sugiura, A; Tyrrel, S F; Seymour, I; Burgess, P J

    2008-01-01

    Macronutrients concentrations were measured during the establishment year of short rotation coppice of Salix viminalis, Populus trichocarpa, Eucalyptus gunnii irrigated with secondary treated effluent. Twenty four plots of 12.25 m2 located in Cranfield, Bedfordshire, UK on heavy fine clay were drip-irrigated in order to maintain their soil moisture at field capacity. Soil water was sampled at 30 cm and 60 cm with soil water suction cup samplers fortnightly. Willow and eucalyptus received more than 900 mm of effluent corresponding to more than 290 kg-N/ha, 30 kg-P/ha and 220 kg-K/ha. Poplar and unplanted plots received less than 190 kg-N/ha, 17 kg-P/ha and 120 kg-K/ha. For soil water nitrogen concentrations as for potassium concentrations, there was an irrigation effect only on eucalyptus planted plots. On all plots, there was no significant effect of tree presence or species. There was no phosphorus measurable in soil water samples. Groundwater chemistry was unaffected by irrigation. Thus, intensive irrigation of short rotation coppice during the establishment year should not be considered as a major threat to groundwater quality. Willows and eucalyptus can absorb almost a third more effluent than poplar and unplanted plots without having any significant effect on soil water chemistry.

  16. Modal Analysis in Periodic, Time-Varying Systems with emphasis to the Coupling between Flexible Rotating Beams and Non-Rotating Flexible Structures

    DEFF Research Database (Denmark)

    Saracho, C. M.; Santos, Ilmar

    2003-01-01

    The analysis of dynamical response of a system built by a non-rotating structure coupled to flexible rotating beams is the purpose of this work. The effect of rotational speed upon the beam natural frequencies is well-known, so that an increase in the angular speeds leads to an increase in beam...

  17. ROLE OF ALLELOPATHY IN THE STIMULATORY AND INHIBITORY EFFECTS OF HAIRY VETCH COVER CROP RESIDUE IN NO-TILLAGE SUSTAINABLE PRODUCTION SYSTEMS

    Science.gov (United States)

    Cover crops can provide multiple benefits to sustainable cropping systems including building soil organic matter, controlling soil and nutrient losses from fields, moderating radiation and moisture exchange, releasing nutrients for subsequent crops, and suppressing weed and pest populations. Many o...

  18. Farm Household Economic Model of The Integrated Crop Livestock System: Conceptual and Empirical Study

    Directory of Open Access Journals (Sweden)

    Atien Priyanti

    2007-06-01

    Full Text Available An integrated approach to enhance rice production in Indonesia is very prospectus throughout the implementation of adapted and liable integrated program. One of the challenges in rice crop sub sector is the stagnation of its production due to the limitation of organic matter availability. This provides an opportunity for livestock development to overcome the problems on land fertility through the use of manure as the source of organic fertilizer. Ministry of Agriculture had implemented a program on Increasing Integrated Rice Productivity with an Integrated Crop Livestock System as one of the potential components since 2002. Integrated crop livestock system program with special reference to rice field and beef cattle is an alternative to enhance the potential development of agriculture sector in Indonesia. The implementation on this integrated program is to enhance rice production and productivity through a system involving beef cattle with its goal on increasing farmers’ income. Household economic model can be used as one of the analysis to evaluate the success of the implemented crop livestock system program. The specificity of the farmers is that rationality behavior of the role as production and consumption decision making. In this case, farmers perform the production to meet home consumption based on the resources that used directly for its production. The economic analysis of farmers household can be described to anticipate policy options through this model. Factors influencing farmers’ decisions and direct interrelations to production and consumption aspects that have complex implications for the farmers’ welfare of the integrated crop livestock system program.

  19. Management of herbicide resistance in wheat cropping systems: learning from the Australian experience.

    Science.gov (United States)

    Walsh, Michael J; Powles, Stephen B

    2014-09-01

    Herbicide resistance continues to escalate in weed populations infesting global wheat (Triticum aestivum L.) crops, threatening grain production and thereby food supply. Conservation wheat production systems are reliant on the use of efficient herbicides providing low-cost, selective weed control in intensive cropping systems. The resistance-driven loss of herbicide resources combined with limited potential for new herbicide molecules means greater emphasis must be placed on preserving existing herbicides. For more than two decades, since the initial recognition of the dramatic consequences of herbicide resistance, the challenge of introducing additional weed control strategies into herbicide-based weed management programmes has been formidable. Throughout this period, herbicide resistance has expanded unabated across the world's wheat production regions. However, in Australia, where herbicide resources have become desperately depleted, the adoption of harvest weed seed control is evidence, at last, of a successful approach to sustainable weed management in wheat production systems. Growers routinely including strategies to target weed seeds during crop harvest, as part of herbicide-based weed management programmes, are now realising significant weed control and crop production benefits. When combined with an attitude of zero weed tolerance, there is evidence of a sustainable weed control future for wheat production systems. The hard-learned lessons of Australian growers can now be viewed by global wheat producers as an example of how to stop the continual loss of herbicide resources in productive cropping systems.

  20. Changes in physical and biological soil quality indicators in a tropical crop system (Havana, Cuba) in response to different agroecological management practices.

    Science.gov (United States)

    Izquierdo, I; Caravaca, F; Alguacil, M M; Roldán, A

    2003-11-01

    The objective of our study was to assess the response of physical (aggregate stability and bulk density) and biological (enzyme activities and microbial biomass) soil quality indicators to the adoption of agroecological management practices, such as the planting of forage species (forage area) and the rotation of local crops (polycrop area), carried out in a representative tropical pasture on an integrated livestock-crop farm. The pasture system was used as control (pasture area). In all three areas, the values of water-soluble C were higher in the rainy season compared to the dry season. Pasture and forage areas had the highest percentage of stable aggregates in the rainy season, while polycrops developed soils with less stable aggregates. Soil bulk density was lower in the pasture and forage areas than in the polycrop area. In the pasture area, the microbial biomass C values, dehydrogenase, urease, protease-BAA, acid phosphatase, and beta-glucosidase activities were higher than in the forage and polycrop areas, particularly in the dry season. The highest increase in the microbial biomass C in the rainy season, with respect to the dry season, was recorded in the pasture area (about 1.2-fold). In conclusion, the planting of forage species can be considered an effective practice for carrying out sustainable, integrated livestock-crop systems, due to its general maintenance of soil quality, while the adoption of polycrop rotations appears to be less favorable because it decreases soil quality.

  1. Rotating pulse valve for downhole fluid telemetry systems

    Energy Technology Data Exchange (ETDEWEB)

    Duckworth, A.

    1993-06-01

    An apparatus for generating pressure pulses in a drilling fluid in a drill collar section of a drill string is described comprising: rotating valve means substantially diametrically mounted in a drill string segment, said rotating valve means alternating between a first position corresponding to more resistance to the flow of drilling fluid and a second position corresponding to less resistance to the flow of drilling fluid, said rotating valve means being impelled by the flow of drilling fluid; and restraining means disposed in the drill collar segment, said restraining means restraining said rotating valve means in said first position and releasing said rotating valve means from said first position in response to control signals indicative of a downhole condition.

  2. Designing a new cropping system for high productivity and sustainable water usage under climate change

    Science.gov (United States)

    Meng, Qingfeng; Wang, Hongfei; Yan, Peng; Pan, Junxiao; Lu, Dianjun; Cui, Zhenling; Zhang, Fusuo; Chen, Xinping

    2017-02-01

    The food supply is being increasingly challenged by climate change and water scarcity. However, incremental changes in traditional cropping systems have achieved only limited success in meeting these multiple challenges. In this study, we applied a systematic approach, using model simulation and data from two groups of field studies conducted in the North China Plain, to develop a new cropping system that improves yield and uses water in a sustainable manner. Due to significant warming, we identified a double-maize (M-M; Zea mays L.) cropping system that replaced the traditional winter wheat (Triticum aestivum L.) –summer maize system. The M-M system improved yield by 14–31% compared with the conventionally managed wheat-maize system, and achieved similar yield compared with the incrementally adapted wheat-maize system with the optimized cultivars, planting dates, planting density and water management. More importantly, water usage was lower in the M-M system than in the wheat-maize system, and the rate of water usage was sustainable (net groundwater usage was ≤150 mm yr‑1). Our study indicated that systematic assessment of adaptation and cropping system scale have great potential to address the multiple food supply challenges under changing climatic conditions.

  3. Dynamics of Phenol Degrading-Iron ReducingBacteria{1mm in Intensive Rice Cropping System

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Field and greenhouse experiments were conducted to investigate theeffects of cropping season, nitrogen fertilizer input and aeratedfallow on the dynamics of phenol degrading-iron reducingbacteria (PD-IRB) in tropical irrigated rice ({ Oryza sativa L.)systems. The PD-IRB population density was monitored at different stagesof rice growth in two cropping seasons (dry and early wet) in acontinuous annual triple rice cropping system under irrigated condition.In this system, the high nitrogen input (195 and 135 kg N ha-1 indry and wet seasons, respectively) plots and control plots receiving noN fertilizer were compared to investigate the effect of nitrogen rate onpopulation size. The phenol degrading-iron reducing bacteria (PD-IRB)were abundant in soils under cropping systems of tropical irrigatedrice. However, density of the bacterial populations varied with ricegrowth stages. Cropping seasons, rhizosphere, and aerated fallow couldaffect the dynamics of PD-IRB. In the field trial, viable counts ofPD-IRB in the topsoil layer (15 cm) ranged between 102 and 108cells per gram of dry soil. A steep increase in viable counts during thesecond half of the cropping season suggested that the population densityof PD-IRB increased at advanced crop-growth stages. Population growth ofPD-IRB was accelerated during the dry season compared to the wet season.In the greenhouse experiment, the adjacent aerated fallow revealed 1-2orders of magnitude higher in most probable number (MPN) of PD-IRB thanthe wet fallow treated plots. As a prominent group of Fe reducingbacteria, PD-IRB predominated in the rhizosphere of rice, since maximumMPN of PD-IRB (2.62108 g-1 soil) was found in rhizospheresoil. Mineral N fertilizer rates showed no significant effect on PD-IRBpopulation density.

  4. Study on the Optimum N Rates Under Spring Cabbage-Maize-Winter Cabbage Rotation System

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In this paper, field trials in two soils with different Nmin were conducted to study the effects of mineral N content (Nmin) in soil on the maximum yield N rate (MYNR), N recovery of cabbage under spring cabbage-maize-winter cabbage rotation system, and the correlation of N fertilization with cabbage yield and quality, and to provide the theoretical basis for N recommendation for high-yield, quality, and safety production of vegetables. The effects of six N rates of 0, 90, 180, 270,360, and 450 kg ha-1 on the yield, N recovery of spring cabbage, maize, and winter cabbage, water-soluble sugar, Vc, and nitrate content of vegetables were observed. The results showed that soil Nmin had a remarkable influence on the MYNR in the first spring cabbage season. The MYNR for spring cabbage lessened in the soil with high Nmin. Soil Nmin could be helpful to N recommendation only for the seasonal growing crop because its effects on the following crop yield was less with the active transformation of soil Nmin. The farmer's practice was 1.8-3.2 times higher than the MYNR of cabbage resulted in the nitrate enrichment of groundwater. Both N application rate and Nmin in the soil profile affected N recovery,whereas, the relay intercropping maize in the cabbage field increased the N recovery at a higher N application rate. Lower N rate (less than 90 kg ha-1) improved the yield and quality of cabbage at the same time; higher N rates increased cabbage yield, but decreased the quality; extremely high N rates of application deceased both yield and quality of cabbage. It was concluded that the soil Nmin had close correlations with MYNR and N recovery of the seasonal growing cabbage. Although the residual effects of the N fertilizer were obvious in Shajiang black meadow soil, cabbage-maize rotation increased the N recovery in treatments with higher N rates. Considering the effects of N rates on cabbage yield and quality, it is necessary to reduce the N rate and lower the yield target for

  5. Using a semi distributed model to enhance communication with stakeholders and participation for designing nitrogen-efficient cropping systems in a catchment

    Science.gov (United States)

    Dupas, Rémi; Parnaudeau, Virginie; Reau, Raymond; Gascuel-Odoux, Chantal; Durand, Patrick

    2013-04-01

    located in Burgundy, France. Data from farm surveys was available for ~300 field plots each year since 2003. We will present how characterization of the cropping systems to be simulated as HSU was done combining this data and local expe