WorldWideScience

Sample records for crop rotation location

  1. Short rotation Wood Crops Program

    Energy Technology Data Exchange (ETDEWEB)

    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.

  2. Crop rotation modelling - A European model intercomparison

    DEFF Research Database (Denmark)

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

    2015-01-01

    crop growth simulation models to predict yields in crop rotations at five sites across Europe under minimal calibration. Crop rotations encompassed 301 seasons of ten crop types common to European agriculture and a diverse set of treatments (irrigation, fertilisation, CO2 concentration, soil types...... accurately than main crops (cereals). The majority of models performed better for the treatments of increased CO2 and nitrogen fertilisation than for irrigation and soil-related treatments. The yield simulation of the multi-model ensemble reduced the error compared to single-model simulations. The low degree...... representation of crop rotations, further research is required to synthesise existing knowledge of the physiology of intermediate crops and of carry-over effects from the preceding to the following crop, and to implement/improve the modelling of processes that condition these effects....

  3. Energy crops in rotation. A review

    Energy Technology Data Exchange (ETDEWEB)

    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

  4. Spatial methods for deriving crop rotation history

    Science.gov (United States)

    Mueller-Warrant, George W.; Trippe, Kristin M.; Whittaker, Gerald W.; Anderson, Nicole P.; Sullivan, Clare S.

    2017-08-01

    Benefits of converting 11 years of remote sensing classification data into cropping history of agricultural fields included measuring lengths of rotation cycles and identifying specific sequences of intervening crops grown between final years of old grass seed stands and establishment of new ones. Spatial and non-spatial methods were complementary. Individual-year classification errors were often correctable in spreadsheet-based non-spatial analysis, whereas their presence in spatial data generally led to exclusion of fields from further analysis. Markov-model testing of non-spatial data revealed that year-to-year cropping sequences did not match average frequencies for transitions among crops grown in western Oregon, implying that rotations into new grass seed stands were influenced by growers' desires to achieve specific objectives. Moran's I spatial analysis of length of time between consecutive grass seed stands revealed that clustering of fields was relatively uncommon, with high and low value clusters only accounting for 7.1 and 6.2% of fields.

  5. Examining cotton in rotation with rice and cotton in rotation with other crops using natural experiment

    Science.gov (United States)

    Sun, Ling; Zhu, Zesheng

    2017-08-01

    This paper is to show the ability of remote sensing image analysis combined with statistical analysis to characterize the environmental risk assessment of cotton in rotation with rice and cotton in rotation with other crops in two ways: (1) description of rotation period of cotton in rotation with rice and cotton in rotation with other crops by the observational study or natural experiment; (2) analysis of rotation period calculation of cotton in rotation with rice and cotton in rotation with other crops. Natural experimental results show that this new method is very promising for determining crop rotation period for estimating regional averages of environmental risk. When it is applied to determining crop rotation period, two requested remote sensing images of regional crop are required at least.

  6. Regional variability of environmental effects of energy crop rotations

    Science.gov (United States)

    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

  7. Effect of crop rotation on soil nutrient balance and weediness in soddy podzolic organic farming fields

    Science.gov (United States)

    Zarina, Livija; Zarina, Liga

    2017-04-01

    The nutrient balance in different crop rotations under organic cropping system has been investigated in Latvia at the Institute of Agricultural Resources and Economics since 2006. Latvia is located in a humid and moderate climatic region where the rainfall exceeds evaporation (soil moisture coefficient > 1) and the soil moisture regime is characteristic with percolation. The average annual precipitation is 670-850 mm. The average temperature varies from -6.7° C in January to 16.5 °C in July. The growing season is 175 - 185 days. The most widespread are podzolic soils and mainly they are present in agricultural fields in all regions of Latvia. In a wider sense the goal of the soil management in organic farming is a creation of the biologically active flora and fauna in the soil by maintaining a high level of soil organic matter which is good for crops nutrient balance. Crop rotation is a central component of organic farming systems and has many benefits, including growth of soil microbial activity, which may increase nutrient availability. The aim of the present study was to calculate nutrient balance for each crop in the rotations and average in each rotation. Taking into account that crop rotations can limit build-up of weeds, additionally within the ERA-net CORE Organic Plus transnational programs supported project PRODIVA the information required for a better utilization of crop diversification for weed management in North European organic arable cropping systems was summarized. It was found that the nutrient balance was influenced by nutrients uptake by biomass of growing crops in crop rotation. The number of weeds in the organic farming fields with crop rotation is dependent on the cultivated crops and the succession of crops in the crop rotation.

  8. Ecoinformatics reveals effects of crop rotational histories on cotton yield.

    Science.gov (United States)

    Meisner, Matthew H; Rosenheim, Jay A

    2014-01-01

    Crop rotation has been practiced for centuries in an effort to improve agricultural yield. However, the directions, magnitudes, and mechanisms of the yield effects of various crop rotations remain poorly understood in many systems. In order to better understand how crop rotation influences cotton yield, we used hierarchical Bayesian models to analyze a large ecoinformatics database consisting of records of commercial cotton crops grown in California's San Joaquin Valley. We identified several crops that, when grown in a field the year before a cotton crop, were associated with increased or decreased cotton yield. Furthermore, there was a negative association between the effect of the prior year's crop on June densities of the pest Lygus hesperus and the effect of the prior year's crop on cotton yield. This suggested that some crops may enhance L. hesperus densities in the surrounding agricultural landscape, because residual L. hesperus populations from the previous year cannot continuously inhabit a focal field and attack a subsequent cotton crop. In addition, we found that cotton yield declined approximately 2.4% for each additional year in which cotton was grown consecutively in a field prior to the focal cotton crop. Because L. hesperus is quite mobile, the effects of crop rotation on L. hesperus would likely not be revealed by small plot experimentation. These results provide an example of how ecoinformatics datasets, which capture the true spatial scale of commercial agriculture, can be used to enhance agricultural productivity.

  9. Ecoinformatics reveals effects of crop rotational histories on cotton yield.

    Directory of Open Access Journals (Sweden)

    Matthew H Meisner

    Full Text Available Crop rotation has been practiced for centuries in an effort to improve agricultural yield. However, the directions, magnitudes, and mechanisms of the yield effects of various crop rotations remain poorly understood in many systems. In order to better understand how crop rotation influences cotton yield, we used hierarchical Bayesian models to analyze a large ecoinformatics database consisting of records of commercial cotton crops grown in California's San Joaquin Valley. We identified several crops that, when grown in a field the year before a cotton crop, were associated with increased or decreased cotton yield. Furthermore, there was a negative association between the effect of the prior year's crop on June densities of the pest Lygus hesperus and the effect of the prior year's crop on cotton yield. This suggested that some crops may enhance L. hesperus densities in the surrounding agricultural landscape, because residual L. hesperus populations from the previous year cannot continuously inhabit a focal field and attack a subsequent cotton crop. In addition, we found that cotton yield declined approximately 2.4% for each additional year in which cotton was grown consecutively in a field prior to the focal cotton crop. Because L. hesperus is quite mobile, the effects of crop rotation on L. hesperus would likely not be revealed by small plot experimentation. These results provide an example of how ecoinformatics datasets, which capture the true spatial scale of commercial agriculture, can be used to enhance agricultural productivity.

  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

    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......Many current organic arable agriculture systems are challenged by a dependency on imported livestock manure from conventional agriculture. At the same time organic agriculture aims at being climate friendly. A life cycle assessment is used in this paper to compare the carbon footprints of different...... 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...

  11. Irrigation management of crops rotations in a changing climate

    Science.gov (United States)

    Rolim, J.; Teixeira, J.; Catalão, J.

    2012-04-01

    Due to climate change we cannot continue to perform irrigation systems design and irrigation management based only on historical records of weather stations, assuming that the statistical parameters of the meteorological data remains unchanged in time, being necessary to take into account the climatic data relative to climate change scenarios. For the Mediterranean basin the various climate models indicate an increase in temperature and a reduction in precipitation and a more frequent occurrence of extreme events which will increase the risk of crop failure. Thus, it is important to adopt strategies to ensure the sustainability of irrigated agriculture in a changing climate. A very interesting technique to achieve this is the adoption of crops rotations, since they increase the heterogeneity of farming systems distributing the risk between crops and minimizing costs. This study aims to evaluate the impact of climate change in the irrigation requirements of crop rotations for the Alentejo region in the South of Portugal, and the ability of crops rotation to reduce these impacts and stabilize crops production. The IrrigRotation software was used to estimate the water requirements of two crop rotations used in the Alentejo region, Sunflower-Wheat-Barley and Sugar beet-Maize-Tomato-Wheat. IrrigRotation is a soil water balance simulation model, continuous in time, based on the dual crop coefficients methodology, which allows to compute the irrigation requirements of crop rotations. The climate data used were the observed data of the Évora and Beja weather stations (1961-90), the A2 and B2 scenarios of the HadRM3P model and the A2 scenarios of the HIRHAMh and HIRHAMhh models (2071-2100). The consideration of a set of climate change scenarios produces as a result a range of values for the irrigation requirements which can be used to define safety margins in irrigation design. The results show that for the Beja clay soils, with high values of soil water storage capacity

  12. Benefits of annual and perennial forages in row crop rotations

    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 corn and soybean stover dry weight, stover mineral concentrations, seed ...

  13. Weed control through crop rotation and alternative management practices

    Directory of Open Access Journals (Sweden)

    Böhm, Herwart

    2014-02-01

    Full Text Available Economic as well as agricultural and socio-political changes have an impact on crop management and thus also on crop rotation design and the related effects on the weed flora. Likewise other changes in cultivation such as reduced tillage practices, earlier sowing date, etc. cause an increase in weed infestation resp. an increased use of herbicides and if so contribute to herbicide resistance. The positive effects of crop rotation, but also of alternative management practices such as choice of varieties, catch crops, mixed cropping, green chop, and the share of predators, as well as methods of direct non-chemical weed control are presented and discussed for both, conventional and organic farming. If alternative management methods should be more practiced, especially trade-offs need to be broken, or incentives be offered.

  14. 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.

  15. Generation of multi annual land use and crop rotation data for regional agro-ecosystem modeling

    Science.gov (United States)

    Waldhoff, G.; Lussem, U.; Sulis, M.; Bareth, G.

    2017-12-01

    For agro-ecosystem modeling on a regional scale with systems like the Community Land Model (CLM), detailed crop type and crop rotation information on the parcel-level is of key importance. Only with this, accurate assessments of the fluxes associated with the succession of crops and their management are possible. However, sophisticated agro-ecosystem modeling for large regions is only feasible at grid resolutions, which are much coarser than the spatial resolution of modern land use maps (usually ca. 30 m). As a result, much of the original information content of the maps has to be dismissed during resampling. Here we present our mapping approach for the Rur catchment (located in the west of Germany), which was developed to address these demands and issues. We integrated remote sensing and geographic information system (GIS) methods to classify multi temporal images of (e.g.) Landsat, RapidEye and Sentinel-2 to generate annual crop maps for the years 2008-2017 at 15 m spatial resolution (accuracy always ca. 90 %). A key aspect of our method is the consideration of crop phenology for the data selection and the analysis. In a GIS, the annul crop maps were integrated to a crop sequence dataset from which the major crop rotations were derived (based on the 10-years). To retain the multi annual crop succession and crop area information at coarser grid resolutions, cell-based land use fractions, including other land use classes were calculated for each year and for various target cell sizes (1-32 arc seconds). The resulting datasets contain the contribution (in percent) of every land use class to each cell. Our results show that parcels with the major crop types can be differentiated with a high accuracy and on an annual basis. The analysis of the crop sequence data revealed a very large number of different crop rotations, but only relatively few crop rotations cover larger areas. This strong diversity emphasizes the importance of information on crop rotations to reduce

  16. Soil tillage practices and crops rotations effects on yields and ...

    African Journals Online (AJOL)

    Methodology and Results: Three soil tillage practices in main plot (T1 = no tillage with direct sowing, T2 = minimum tillage by soil scarifying with IR12 tool and T3 = conventional tillage with animals drawn plough) were compared and combined to four crops rotation systems, in a split-plot experimental design. Soil chemical ...

  17. 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

  18. Nitrate leaching from an organic dairy crop rotation: the effect of manure type, N-input and improved crop rotation

    OpenAIRE

    Eriksen, J.; Askegaard, M.; Kristensen, K.

    2004-01-01

    Four management systems combining high and low livestock densities (0.7 and 1.4 LU ha-1) and different types of organic manure (slurry and straw based FYM) were applied to an organic dairy crop rotation (barley [undersown] – grass-clover – grass-clover – barley/pea – oats – fodder beet) between 1998 and 2001. The effects of the management systems on crop yields and nitrate leaching were measured. In all four years nitrate leaching, as determined using ceramic suction cups, was higher in the t...

  19. 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.

  20. Grass plants crop water consumption model in urban parks located ...

    African Journals Online (AJOL)

    use

    2011-12-14

    Dec 14, 2011 ... Grass plants crop water consumption model in urban parks located in three different ... The result of calculations, using the climate data of July, value of the province of Antalya were. ETo=7,10464 mm/day, for Ankara .... method is recommended by Food and Agriculture. Organisation (FAO) (Allen et al., ...

  1. Overall assessment of soil quality on humid sandy loams: Effects of location, rotation and tillage

    DEFF Research Database (Denmark)

    Abdollahi, Lotfollah; Hansen, Elly Møller; Rickson, J.M.

    2015-01-01

    Conservation tillage and diversified crop rotations have been suggested as appropriate alternative soil management systems to sustain soil quality. The purpose of this study was to quantify the effect of implementing three crop rotations (R2–R4) on soil structural changes and the “productivity...... function” of soil. R2 is a winter-dominated crop rotation (winter wheat was the main crop) with straw residues incorporated. R3 is a mix of winter and spring crops with straw residues removed. R4 is the same mix of crops as in R3, but with straw residues incorporated. Three tillage systems were used...... the correlation between the soil quality indices and relative crop yield. Relevant soil properties for calculating the soil quality indices were measured or obtained from previous publications. Crop rotation affected the soil structure and RY. The winter-dominated crop rotation (R2) resulted in the poorest soil...

  2. Closed Loop Short Rotation Woody Biomass Energy Crops

    Energy Technology Data Exchange (ETDEWEB)

    Brower, Michael [CRC Development, LLC, Oakland, CA (United States)

    2012-09-30

    CRC Development LLC is pursuing commercialization of shrub willow crops to evaluate and confirm estimates of yield, harvesting, transportation and renewable energy conversion costs and to provide a diverse resource in its supply portfolio.The goal of Closed Loop Short Rotation Woody Biomass Energy Crops is supply expansion in Central New York to facilitate the commercialization of willow biomass crops as part of the mix of woody biomass feedstocks for bioenergy and bioproducts. CRC Development LLC established the first commercial willow biomass plantation acreage in North America was established on the Tug Hill in the spring of 2006 and expanded in 2007. This was the first 230- acres toward the goal of 10,000 regional acres. This project replaces some 2007-drought damaged acreage and installs a total of 630-acre new planting acres in order to demonstrate to regional agricultural producers and rural land-owners the economic vitality of closed loop short rotation woody biomass energy crops when deployed commercially in order to motivate new grower entry into the market-place. The willow biomass will directly help stabilize the fuel supply for the Lyonsdale Biomass facility, which produces 19 MWe of power and exports 15,000 pph of process steam to Burrows Paper. This project will also provide feedstock to The Biorefinery in New York for the manufacture of renewable, CO2-neutral liquid transportation fuels, chemicals and polymers. This project helps end dependency on imported fossil fuels, adds to region economic and environmental vitality and contributes to national security through improved energy independence.

  3. Carbon storage and recycling in short-rotation energy crops

    International Nuclear Information System (INIS)

    Ranney, J.W.; Wright, L.L.; Mitchell, C.P.

    1991-01-01

    Short-rotation energy crops can play a significant role in storing carbon compared to the agricultural land uses they would displace. However, the benefits from these plantations in avoiding further use of fossil fuel and in taking pressure off of native forests for energy uses provides longer term carbon benetfits than the plantation carbon sequestration itself. The fast growth and harvest frequency of plantations tends to limit the amount of above and below-ground carbon storage in them. The primary components of plantation carbon sequestering compared to sustained agricultural practices involve above-ground wood, possible increased soil carbon, litter layer formation, and increased root biomass. On the average, short-rotation plantations in total may increase carbon inventories by about 30 to 40 tonnes per hectare over about a 20- to 56-year period when displacing cropland. This is about doubling in storage over cropland and about one-half the storage in human-impacted forests. The sequestration benefit of wood energy crops over cropland would be negated in about 75 to 100 years by the use of fossil fuels to tend the plantations and handle biomass. Plantation interactions with other land uses and total landscape carbon inventory is important in assessing the relative role plantations play in terrestrial and atmospheric carbon dynamics. It is speculated that plantations, when viewed in this context. could trencrate a global leveling of net carbon emissions for approximately 10 to 20 years

  4. Nitrogen leaching: A crop rotation perspective on the effect of N surplus, field management and use of catch crops

    DEFF Research Database (Denmark)

    De Notaris, Chiara; Rasmussen, Jim; Sørensen, Peter

    2018-01-01

    Components of the field nitrogen (N) balance (input and surplus) are often used to predict nitrate leaching from agricultural lands. However, management factors, such as use of catch crops, greatly affect the actual loss and are a key to reduce N leaching. The present study is based on the 4th...... cycle of a long-term crop rotation experiment in Denmark, and it aims to quantify, from a crop rotation perspective, the influence on N leaching from N input and surplus or management factors. The experiment included three cropping systems (two organic and one conventional) with or without use of animal......, with legume-based catch crops being as effective as non-legumes. Animal manure increased N leaching in one of the organic systems. The organic system with two years of green manure per rotation cycle was the one at highest risk of N leaching, especially from crops following green manure incorporation. Spring...

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

    Science.gov (United States)

    Felipe G. Sanchez; Mark Coleman; Charles T. Garten; Robert J. Luxmoore; John A. Stanturf; Carl Trettin; Stan D. Wullschleger

    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...

  6. Nitrogen, tillage, and crop rotation effects on nitrous oxide emissions from irrigated cropping systems.

    Science.gov (United States)

    Halvorson, Ardell D; Del Grosso, Stephen J; Reule, Curtis A

    2008-01-01

    We evaluated the effects of irrigated crop management practices on nitrous oxide (N(2)O) emissions from soil. Emissions were monitored from several irrigated cropping systems receiving N fertilizer rates ranging from 0 to 246 kg N ha(-1) during the 2005 and 2006 growing seasons. Cropping systems included conventional-till (CT) continuous corn (Zea mays L.), no-till (NT) continuous corn, NT corn-dry bean (Phaseolus vulgaris L.) (NT-CDb), and NT corn-barley (Hordeum distichon L.) (NT-CB). In 2005, half the N was subsurface band applied as urea-ammonium nitrate (UAN) at planting to all corn plots, with the rest of the N applied surface broadcast as a polymer-coated urea (PCU) in mid-June. The entire N rate was applied as UAN at barley and dry bean planting in the NT-CB and NT-CDb plots in 2005. All plots were in corn in 2006, with PCU being applied at half the N rate at corn emergence and a second N application as dry urea in mid-June followed by irrigation, both banded on the soil surface in the corn row. Nitrous oxide fluxes were measured during the growing season using static, vented chambers (1-3 times wk(-1)) and a gas chromatograph analyzer. Linear increases in N(2)O emissions were observed with increasing N-fertilizer rate, but emission amounts varied with growing season. Growing season N(2)O emissions were greater from the NT-CDb system during the corn phase of the rotation than from the other cropping systems. Crop rotation and N rate had more effect than tillage system on N(2)O emissions. Nitrous oxide emissions from N application ranged from 0.30 to 0.75% of N applied. Spikes in N(2)O emissions after N fertilizer application were greater with UAN and urea than with PCU fertilizer. The PCU showed potential for reducing N(2)O emissions from irrigated cropping systems.

  7. Soil total carbon and nitrogen and crop yields after eight years of tillage, crop rotation, and cultural practice

    Science.gov (United States)

    Information on the long-term effect of management practices on soil C and N stocks is lacking. An experiment was conducted from 2004 to 2011 in the northern Great Plains, USA to examine the effects of tillage, crop rotation, and cultural practice on annualized crop biomass (stems + leaves) residue r...

  8. Biofuels, bioenergy, and bioproducts from sustainable agricultural and forest crops: proceedings of the short rotation crops international conference

    Science.gov (United States)

    Ronald S., Jr. Zalesny; Rob Mitchell; Jim, eds. Richardson

    2008-01-01

    The goal of this conference was to initiate and provide opportunities for an international forum on the science and application of producing both agricultural and forest crops for biofuels, bioenergy, and bioproducts. There is a substantial global need for development of such systems and technologies that can economically and sustainably produce short rotation crops...

  9. ECONOMIC BACKGROUND CROP ROTATION AS A WAY TO PREVENT THE DEGRADATION OF AGRICULTURAL LANDSCAPES

    Directory of Open Access Journals (Sweden)

    Shevchenko O.

    2017-05-01

    Full Text Available This article explores that to successfully combat land degradation on lands occupied in agriculture, it is necessary to conduct complex soil conservation measures constitute a single interconnected system and protect soil from degradation. Found that rotation – a reasonable compromise between the main requirements of production, organization of territory and environment, placing crops in view of a favorable combination; compliance with acceptable saturation parameters optimally varying cultures, and thus the possible timing of a return to their previous cultivation while taking into account the duration of the accepted rotation. Determined that the implementation and observance of crop rotation and better ensure the replenishment of nutrients of the soil, improving and maintaining its favorable physical properties, prevent the emergence of weeds, pests and pathogens cultivated crops and preventing the depletion of soil degradation processes and development. Found that scientifically based crop rotation is the basis for the use of all complex farming practices, differentiated cultivation, rational use of fertilizers and caring for plants. Rotation is correct – it agroecosystem, which created the best conditions for growth and development of various crops, thus providing a growing high and stable yields, obtaining high quality products. Soil and climatic conditions, specialty farms, crops structure and their biological characteristics defined as the type of crop rotation and crop rotation order. Each rotation should be selected such status, which would provide the greatest yield per unit area of rational use of all land. Therefore, proper placement crops in crop rotation must necessarily take into account the requirements of crops to their predecessor, thus it must evaluate not only the direct action of the first culture, but also take into account the impact of the latter on the following crops rotation. On unproductive and degraded lands is

  10. Effects of Crop Rotation and N-P Fertilizer Rate on Grain Yield and ...

    African Journals Online (AJOL)

    A trial was conducted to determine the effects of crop rotation with N-P rates on grain yield of maize and soil fertility in Bako over a period of five years. The experiment was laid out in a randomized complete block design in factorial arrangement with rotation crops (Niger seed, haricot bean and tef) as main factor and two ...

  11. Row and forage crop rotation effects on maize mineral nutrition and yield

    Science.gov (United States)

    Extended crop rotations provide many attributes in support of sustainable agriculture. Objectives were to investigate rotations that included row crops and forages in terms of their effects on soil characteristics as well as on maize (Zea mays L.) stover biomass, grain yield, and mineral components...

  12. Crop rotation in the Valle Calido del Alto Magdalena a sustainable focus of high yield

    International Nuclear Information System (INIS)

    Alfaro Rodriguez, Ricardo; Maria Caicedo, Antonio; Amezquita Collazos, Edgar; Castro Franco, Hugo Eduardo

    1996-01-01

    Experiments were carried out during five years at the Nataima Research Center, located at 431 m.a.s.l, with average temperature of 28 Celsius degrades and annual rainfall of 1274 Boyaca mm, on a soil classified as Arenic Haplustalf, to evaluate different crops rotation based on rice and sorghum; the combinations used were as follows; rice-rice (R-R), rice-- soybean (R-SY), rice-crotalaria-sorghum (R-C-S), sorghum-sorghum (S-S), sorghum-soybean (S-SY) and cotton-sorghum (Al-S). Simultaneously it was evaluated the response to four nitrogen levels, which allowed to find out yield functions and optimum economical. The rotations S-SY, R-SY and AI-S have been the best qualified from an environmental perspective. Sorghum-soybean rotation presents increases in yield compared with expected values, which allows thinking that it is a truly sustainable rotation. This rotation also had an excellent profitability and for that reason is considered the best option within the goals of this work

  13. 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

    to the soil quality estimates. We found significant effect of both rotation and tillage on visual soil structure at both times of assessment. Poor soil structure was found for NT except when combined with a diverse crop rotation (R6). The soil core pore characteristics data also displayed a significant effect...... of tillage but only a weak insignificant effect of rotation. The drop shatter results were in accordance with the visual assessment data. Crop yield correlated significantly with the visual soil structure scores. We conclude that a diverse crop rotation was needed for an optimal performance of NT......Tillage and rotation are fundamental factors influencing soil quality and thus the sustainability of cropping systems. Many studies have focused on the effects of either tillage or rotation, but few have quantified the long term integrated effects of both. We studied the issue using a 30-year old...

  14. Comparison of the effects of different crop rotation systems on winter ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-11-19

    Nov 19, 2008 ... Southern Marmara Region, Turkey. In this study (1995-2001), two different crop rotation systems were carried out: winter wheat and sunflower as main crops experiments. Results were evaluated in terms of crop yielding ability, soil fertility and economic aspects. The sunflower-rapeseed-wheat, rapeseed-.

  15. 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

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

    Directory of Open Access Journals (Sweden)

    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.

  17. The role of short-rotation woody crops in sustainable development

    International Nuclear Information System (INIS)

    Shepard, J.P.; Tolbert, V.R.

    1996-01-01

    One answer to increase wood production is by increasing management intensity on existing timberland, especially in plantation forests. Another is to convert land currently in agriculture to timberland. Short-rotation woody crops can be used in both cases. But, what are the environmental consequences? Short-rotation woody crops can provide a net improvement in environmental quality at both local and global scales. Conversion of agricultural land to short-rotation woody crops can provide the most environmental quality enhancement by reducing erosion, improving soil quality, decreasing runoff, improving groundwater quality, and providing better wildlife habitat. Forest products companies can use increased production from intensively managed short-rotation woody crop systems to offset decreased yield from the portion of their timberland that is managed less intensively, e.g. streamside management zones and other ecologically sensitive or unique areas. At the global scale, use of short-rotation woody crops for bioenergy is part of the solution to reduce greenhouse gases produced by burning fossil fuels. Incorporating short-rotation woody crops into the agricultural landscape also increases storage of carbon in the soil, thus reducing atmospheric concentrations. In addition, use of wood instead of alternatives such as steel, concrete, and plastics generally consumes less energy and produces less greenhouse gases. Cooperative research can be used to achieve energy, fiber, and environmental goals. This paper will highlight several examples of ongoing cooperative research projects that seek to enhance the environmental aspects of short-rotation woody crop systems. Government, industry, and academia are conducting research to study soil quality, use of mill residuals, nutrients in runoff and groundwater, and wildlife use of short-rotation woody crop systems in order to assure the role of short-rotation crops as a sustainable way of meeting society's needs

  18. Plant Residual Management in different Crop Rotations System on Potato Tuber Yield Loss Affected by Wireworms

    Directory of Open Access Journals (Sweden)

    A. Zarea Feizabadi

    2016-07-01

    Full Text Available Introduction: Selection a proper crop rotation based on environmental conservation rules is a key factor for increasing long term productivity. On the other hand, the major problem in reaching agricultural sustainability is lack of soil organic matter. Recently, a new viewpoint has emerged based on efficient use of inputs, environmental protection, ecological economy, food supply and security. Crop rotation cannot supply and restore plant needed nutrients, so gradually the productivity of rotation system tends to be decreased. Returning the plant residues to the soil helps to increase its organic matter and fertility in long-term period. Wireworms are multi host pests and we can see them in wheat and barley too. The logic way for their control is agronomic practices like as crop rotation. Wireworms’ population and damages are increased with using grasses and small seed gramineas in mild winters, variation in cropping pattern, reduced chemical control, and cover crops in winter. In return soil cultivation, crop rotation, planting date, fertilizing, irrigation and field health are the examples for the effective factors in reducing wireworms’ damage. Materials and Methods: In order to study the effect of crop rotations, residue management and yield damage because of wireworms’ population in soil, this experiment was conducted using four rotation systems for five years in Jolgeh- Rokh agricultural research station. Crop rotations were included, 1 Wheat monoculture for the whole period (WWWWW, 2 Wheat- wheat- wheat- canola- wheat (WWWCW, 3 Wheat- sugar beet- wheat- potato- wheat (WSWPW, 4 Wheat- maize- wheat- potato- wheat (WMWPW as main plots and three levels of returning crop residues to soil (returning 0, 50 and 100% produced crop residues to soil were allocated as sub plots. This experiment was designed as split plot based on RCBD design with three replications. After ending each rotation treatment, the field was sowed with potato cv. Agria

  19. Effects of Neonicotinoids and Crop Rotation for Managing Wireworms in Wheat Crops.

    Science.gov (United States)

    Esser, Aaron D; Milosavljević, Ivan; Crowder, David W

    2015-08-01

    Soil-dwelling insects are severe pests in many agroecosystems. These pests have cryptic life cycles, making sampling difficult and damage hard to anticipate. The management of soil insects is therefore often based on preventative insecticides applied at planting or cultural practices. Wireworms, the subterranean larvae of click beetles (Coleoptera: Elateridae), have re-emerged as problematic pests in cereal crops in the Pacific Northwestern United States. Here, we evaluated two management strategies for wireworms in long-term field experiments: 1) treating spring wheat seed with the neonicotinoid thiamethoxam and 2) replacing continuous spring wheat with a summer fallow and winter wheat rotation. Separate experiments were conducted for two wireworm species--Limonius californicus (Mannerheim) and Limonius infuscatus (Motschulsky). In the experiment with L. californicus, spring wheat yields and economic returns increased by 24-30% with neonicotinoid treatments. In contrast, in the experiment with L. infuscatus, spring wheat yields and economic returns did not increase with neonicotinoids despite an 80% reduction in wireworms. Thus, the usefulness of seed-applied neonicotinoids differed based on the wireworm species present. In experiments with both species, we detected significantly fewer wireworms with a no-till summer fallow and winter wheat rotation compared with continuous spring wheat. This suggests that switching from continuous spring wheat to a winter wheat and summer fallow rotation may aid in wireworm management. More generally, our results show that integrated management of soil-dwelling pests such as wireworms may require both preventative insecticide treatments and cultural practices. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Crop rotation modelling-A European model intercomparison

    Czech Academy of Sciences Publication Activity Database

    Kollas, C.; Kersebaum, K. C.; Nendel, C.; Manevski, K.; Müller, C.; Palosuo, T.; Armas-Herrera, C.; Beaudoin, N.; Bindi, M.; Charefeddine, M.; Conradt, T.; Constantin, J.; Eitzinger, J.; Ewert, F.; Ferrise, R.; Gaiser, T.; de Cortazar-Atauri, I. G.; Giglio, L.; Hlavinka, Petr; Hoffman, H.; Hofmann, M.; Launay, M.; Manderscheid, R.; Mary, B.; Mirschel, W.; Moriondo, M.; Olesen, J. E.; Öztürk, I.; Pacholski, A.; Ripoche-Wachter, D.; Roggero, P. P.; Roncossek, S.; Rötter, R. P.; Ruget, F.; Sharif, B.; Trnka, Miroslav; Ventrella, D.; Waha, K.; Wegehenkel, M.; Weigel, H-J.; Wu, L.

    2015-01-01

    Roč. 70, oct (2015), s. 98-111 ISSN 1161-0301 Institutional support: RVO:67179843 Keywords : model ensemble * crop simulation models * catch crop * intermediate crop * treatment * Multi-year Subject RIV: GC - Agronomy Impact factor: 3.186, year: 2015

  1. Modeling the potential benefits of catch-crop introduction in fodder crop rotations in a Western Europe landscape.

    Science.gov (United States)

    Moreau, P; Ruiz, L; Raimbault, T; Vertès, F; Cordier, M O; Gascuel-Odoux, C; Masson, V; Salmon-Monviola, J; Durand, P

    2012-10-15

    Among possible mitigation options to reduce agricultural-borne nitrate fluxes to water bodies, introduction of catch crop before spring crops is acknowledged as a cost-efficient solution at the plot scale, but it was rarely assessed at the catchment level. This study aims to evaluate a set of catch crop implantation scenarios and their consequences in a coastal catchment prone to eutrophication. The objectives are (i) to discuss the potential benefits of catch crop introduction taking into account the limitations due to the physiographic and agricultural context of the area (ii) to propose a multicriteria classification of these scenarios as a basis for discussion with stakeholders. We used the distributed agro-hydrological model TNT2 to simulate 25 scenarios of catch crop management, differing in length of catch crop growing period, place in the crop rotation and residue management. The scenarios were classified considering the variations in main crop yields and either nitrogen fluxes in stream or the global nitrogen mass balance at the catchment level. The simulations showed that in the catchment studied, little improvement can be expected from increasing the catch crop surface. Catch crop cultivation was always beneficial to reduce nitrogen losses, but led to adverse effects on main crop yields in some cases. Among the scenarios involving additional catch crop surface, introducing catch crop between two winter cereals appeared as the most promising. The classification of scenarios depended on the chosen criteria: when considering only the reduction of nitrogen fluxes in streams, exporting catch crop residues was the most efficient while when considering the global nitrogen mass balance, soil incorporation of catch crop residues was the most beneficial. This work highlights the interest, while using integrated models, of assessing simulated scenarios with multicriteria approach to provide stakeholder with a picture as complete as possible of the consequences of

  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. Estimation of above ground biomass for multi-stemmed short-rotation woody crops

    Science.gov (United States)

    Brian A. Byrd; Wilson G. Hood; Michael C. Tyree; Dylan N. Dillaway

    2015-01-01

    With the increasing interest in short-rotation woody crop (SRWC) systems, an accurate yet quick, non-destructive means for determining aboveground biomass is necessary from both management and research perspectives.

  4. The use of crop rotation for mapping soil organic content in farmland

    Science.gov (United States)

    Yang, Lin; Song, Min; Zhu, A.-Xing; Qin, Chengzhi

    2017-04-01

    Most of the current digital soil mapping uses natural environmental covariates. However, human activities have significantly impacted the development of soil properties since half a century, and therefore become an important factor affecting soil spatial variability. Many researches have done field experiments to show how soil properties are impacted and changed by human activities, however, spatial variation data of human activities as environmental covariates have been rarely used in digital soil mapping. In this paper, we took crop rotation as an example of agricultural activities, and explored its effectiveness in characterizing and mapping the spatial variability of soil. The cultivated area of Xuanzhou city and Langxi County in Anhui Province was chosen as the study area. Three main crop rotations,including double-rice, wheat-rice,and oilseed rape-cotton were observed through field investigation in 2010. The spatial distribution of the three crop rotations in the study area was obtained by multi-phase remote sensing image interpretation using a supervised classification method. One-way analysis of variance (ANOVA) for topsoil organic content in the three crop rotation groups was performed. Factor importance of seven natural environmental covariates, crop rotation, Land use and NDVI were generated by variable importance criterion of Random Forest. Different combinations of environmental covariates were selected according to the importance rankings of environmental covariates for predicting SOC using Random Forest and Soil Landscape Inference Model (SOLIM). A cross validation was generated to evaluated the mapping accuracies. The results showed that there were siginificant differences of topsoil organic content among the three crop rotation groups. The crop rotation is more important than parent material, land use or NDVI according to the importance ranking calculated by Random Forest. In addition, crop rotation improved the mapping accuracy, especially for the

  5. Effects of crop rotation on weed density, biomass and yield of wheat (Titicum aestivum L.)

    OpenAIRE

    A. Zareafeizabadi; H.R. Rostamzadeh

    2016-01-01

    In order to study the weed populations in wheat, under different crop rotations an experiment was carried out at Agricultural Research Station of Jolgeh Rokh, Iran. During growing season this project was done in five years, based on Randomized Complete Bloch Design with three replications, on Crop rotations included: wheat monoculture for the whole period (WWWWW), wheat- wheat- wheat- canola- wheat (WWWCW), wheat- sugar beet- wheat-sugar beet- wheat (WSWSW), wheat- potato- wheat- potato- whea...

  6. 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)

  7. Effects of organic manure and crop rotation system on potato ...

    African Journals Online (AJOL)

    Lack of sustainable soil fertility management system is a critical challenge in the highlands of Awi Zone. Important physicochemical properties of the soil are below the critical level to support crop growth. Hence, a study was undertaken with the aim of improving the yield of potato through organic treatments and sound crop ...

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

    International Nuclear Information System (INIS)

    Tolbert, V.R.; Thornton, F.C.; Joslin, J.D.

    1997-01-01

    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. These field plot studies are serving as the basis for a water shed study initiated in 1997. Results from the two studies will be used to develop and model nutrient and hydrologic budgets for woody crop plantings to identify potential constraints to sustainable deployment of short-rotation woody crops in the southeastern United States. (author)

  9. Performance of process-based models for simulation of grain N in crop rotations across Europe

    DEFF Research Database (Denmark)

    Yin, Xiaogang; Kersebaum, KC; Kollas, C

    2017-01-01

    and rainfed treatments. Moreover, the multi-model mean provided better predictions of grain N compared to any individual model. In regard to the Individual models, DAISY, FASSET, HERMES, MONICA and STICS are suitable for predicting grain N of the main crops in typical European crop rotations, which all...

  10. Crop rotations and poultry litter impact dynamic soil chemical properties and soil biota long-term

    Science.gov (United States)

    Dynamic soil physiochemical interactions with conservation agricultural practices and soil biota are largely unknown. Therefore, this study aims to quantify long-term (12-yr) impacts of cover crops, poultry litter, crop rotations, and conservation tillage and their interactions on soil physiochemica...

  11. 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...

  12. 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. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  13. 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

  14. Can non-inversion tillage and straw retainment reduce N leaching in cereal based crop rotations?

    DEFF Research Database (Denmark)

    Hansen, Elly Møller; Munkholm, Lars Juhl; Melander, Bo

    2010-01-01

    Finding ways of reducing nitrate leaching in Northern Europe has become an extremely important task, especially under the projected climate changes that are expected to exacerbate the problem. To this end, two field experiments were established under temperate coastal climate conditions to evaluate....../winter crop rotations, probably due to the spring/winter crop rotation including peas, which may be considered a high-risk crop. Our study highlights that management practices that improve biomass production throughout the year are crucial in order to tighten the nitrogen cycle and thereby reduce nitrate...

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

    DEFF Research Database (Denmark)

    Yin, Xiaogang; Kersebaum, Kurt C; Kollas, Chris

    2017-01-01

    simulating different treatments (catch crops, CO2 concentrations, irrigation, N application, residues and tillage) in four multi-year rotation experiments in Europe to assess modelling accuracy. Seven grain and seed crops in four rotation systems in Europe were included in the study, namely winter wheat...... than a random single model. Models correctly simulated the effects of enhanced N input on grain N of winter wheat and winter barley, whereas effects of tillage and irrigation were less well estimated. However, the use of continuous simulation did not improve the simulations as compared to single year......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...

  16. [Effects of tobacco garlic crop rotation and intercropping on tobacco yield and rhizosphere soil phosphorus fractions].

    Science.gov (United States)

    Tang, Biao; Zhang, Xi-zhou; Yang, Xian-bin

    2015-07-01

    A field plot experiment was conducted to investigate the tobacco yield and different forms of soil phosphorus under tobacco garlic crop rotation and intercropping patterns. The results showed that compared with tobacco monoculture, the tobacco yield and proportion of middle/high class of tobacco leaves to total leaves were significantly increased in tobacco garlic crop rotation and intercropping, and the rhizosphere soil available phosphorus contents were 1.3 and 1.7 times as high as that of tobacco monoculture at mature stage of lower leaf. For the inorganic phosphorus in rhizosphere and non-rhizosphere soil in different treatments, the contents of O-P and Fe-P were the highest, followed by Ca2-P and Al-P, and Ca8-P and Ca10-P were the lowest. Compared with tobacco monoculture and tobacco garlic crop intercropping, the Ca2-P concentration in rhizosphere soil under tobacco garlic crop rotation at mature stage of upper leaf, the Ca8-P concentration at mature stage of lower leaf, and the Ca10-P concentration at mature stage of middle leaf were lowest. The Al-P concentrations under tobacco garlic crop rotation and intercropping were 1.6 and 1.9 times, and 1.2 and 1.9 times as much as that under tobacco monoculture in rhizosphere soil at mature stages of lower leaf and middle leaf, respectively. The O-P concentrations in rhizosphere soil under tobacco garlic crop rotation and intercropping were significantly lower than that under tobacco monoculture. Compared with tobacco garlic crop intercropping, the tobacco garlic crop rotation could better improve tobacco yield and the proportion of high and middle class leaf by activating O-P, Ca10-P and resistant organic phosphorus in soil.

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

    Directory of Open Access Journals (Sweden)

    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

  18. EVALUATION OF DIFFERENT PHENOLOGICAL INFORMATION TO MAP CROP ROTATION IN COMPLEX IRRIGATED INDUS BASIN

    Directory of Open Access Journals (Sweden)

    A. Ismaeel

    2018-04-01

    Full Text Available Accurate information of crop rotation in large basin is essential for policy decisions on land, water and nutrient resources around the world. Crop area estimation using low spatial resolution remote sensing data is challenging in a large heterogeneous basin having more than one cropping seasons. This study aims to evaluate the accuracy of two phenological datasets individually and in combined form to map crop rotations in complex irrigated Indus basin without image segmentation. Phenology information derived from Normalized Difference Vegetation Index (NDVI and Leaf Area Index (LAI of Moderate Resolution Imaging Spectroradiometer (MODIS sensor, having 8-day temporal and 1000 m spatial resolution, was used in the analysis. An unsupervised (temporal space clustering to supervised (area knowledge and phenology behavior classification approach was adopted to identify 13 crop rotations. Estimated crop area was compared with reported area collected by field census. Results reveal that combined dataset (NDVI*LAI performs better in mapping wheat-rice, wheat-cotton and wheat-fodder rotation by attaining root mean square error (RMSE of 34.55, 16.84, 20.58 and mean absolute percentage error (MAPE of 24.56 %, 36.82 %, 30.21 % for wheat, rice and cotton crop respectively. For sugarcane crop mapping, LAI produce good results by achieving RMSE of 8.60 and MAPE of 34.58 %, as compared to NDVI (10.08, 40.53 % and NDVI*LAI (10.83, 39.45 %. The availability of major crop rotation statistics provides insight to develop better strategies for land, water and nutrient accounting frameworks to improve agriculture productivity.

  19. Irrigation treatments, water use efficiency and crop sustainability in cereal-forage rotations in Mediterranean environment

    Directory of Open Access Journals (Sweden)

    Pasquale Martiniello

    2012-10-01

    Full Text Available Agricultural systems based on crop rotation are beneficial to crop sustainability and productivity. Wheat-forage rotations combined with irrigation are the agronomic techniques best able to exploit Mediterranean environmental conditions. This paper describes a long-term field trial to ascertain the effect of combined irrigation and durum wheat-forage rotations on crop yield and soil chemical properties. The two forage crops: annual grass-clover winter binary mixture and perennial lucerne were carried out through 1991-2008 under rainfed and irrigated treatments. The experiments were used to highlight the effect of irrigation and wheat-forage crop rotations on water use efficiency (WUE and sustainability of organic matter (OM in topsoil. Irrigation increased the dry matter (DM of annual binary mixture and lucerne by 49.1% and 66.9%, respectively. Continuous wheat rotation reduced seed yield (SY, stability of production, and crude protein (CP characteristics of kernel and OM in topsoil. The yearly gain in wheat after forage crops was 0.04 t (ha yr-1 under rainfed and 0.07 t (ha yr-1 under irrigation treatments. The CP and soil OM of wheat forage crops rotations, compared with those of continuous wheat under rainfed and irrigated was a 0.8 and 0.5 % increase in CP and 5.1 and 4.4 in OM, respectively. The rotations of annual grass-clover winter binary mixture and lucerne meadow under both irrigated treatments increased the OM over continuous wheat (9.3 % and 8.5 in annual grass-clover winter binary mixture and 12.5 and 9.5 lucerne meadow under rainfed and irrigation, respectively. Irrigation reduced the impact of weather on crop growing, reducing water use efficiency (mean over rotations for DM production (15.5 in meadow and 17.5 in annual grass-clover winter binary mixture [L water (kg DM-1] and wheat SY. However, the agronomic benefits achieved by forage crops in topsoil are exhausted after three years of continuous wheat rotation.

  20. Crop rotation with no-till methods in cotton production of Uzbekistan

    Directory of Open Access Journals (Sweden)

    Botir Khaitov

    2014-01-01

    Full Text Available Many soils of Uzbekistan have low water and nutrient holding capacity because of their sandy texture, low organic matter concentrations and degradation caused by long years of cotton monoculture. Conservation tillage production systems have the potential to increase the productivity of these soils by increasing soil humus and nitrogen content. As practiced conservation tillage helped to lessen N leaching losses, holding more of these elements within the topsoil as well as increase crop productivity. Conventional tillage cotton/wheat/maize crop rotation has resulted very low humus and nitrogen content in soil by degreasing crop yield. Therefore, the effects of tillage, and crop rotation were examined on growth and yield of crops in three cotton-based rotation systems, (i cotton/wheat/maize, (ii cotton/wheat/sorghum and (iii cotton/wheat/soybean, in Tashkent region in middle east of Uzbekistan. This obtained result suggests that no tillage with inserting legumes in crop rotation is able to improve soil quality and plant productivity.

  1. Modelling soil properties in a crop field located in Croatia

    Science.gov (United States)

    Bogunovic, Igor; Pereira, Paulo; Millan, Mesic; Percin, Aleksandra; Zgorelec, Zeljka

    2016-04-01

    Development of tillage activities had negative effects on soil quality as destruction of soil horizons, compacting and aggregates destruction, increasing soil erosion and loss of organic matter. For a better management in order to mitigate the effects of intensive soil management in land degradation it is fundamental to map the spatial distribution of soil properties (Brevik et al., 2016). The understanding the distribution of the variables in space is very important for a sustainable management, in order to identify areas that need a potential intervention and decrease the economic losses (Galiati et al., 2016). The objective of this work is study the spatial distribution of some topsoil properties as clay, fine silt, coarse silt, fine sand, coarse sand, penetration resistance, moisture and organic matter in a crop field located in Croatia. A grid with 275x25 (625 m2) was designed and a total of 48 samples were collected. Previous to data modelling, data normality was checked using the Shapiro wilk-test. As in previous cases (Pereira et al., 2015), data did not followed the normal distribution, even after a logarithmic (Log), square-root, and box cox transformation. Thus, for modeling proposes, we used the log transformed data, since was the closest to the normality. In order to identify groups among the variables we applied a principal component analysis (PCA), based on the correlation matrix. On average clay content was 15.47% (±3.23), fine silt 24.24% (±4.08), coarse silt 35.34% (±3.12), fine sand 20.93% (±4.68), coarse sand 4.02% (±1.69), penetration resistance 0.66 MPa (±0.28), organic matter 1.51% (±0.25) and soil moisture 32.04% (±3.27). The results showed that the PCA identified three factors explained at least one of the variables. The first factor had high positive loadings in soil clay, fine silt and organic matter and a high negative loading in fine sand. The second factor had high positive loadings in coarse sand and moisture and a high

  2. Crop rotation and tillage system effects on reducing ryegrass ...

    African Journals Online (AJOL)

    Under the Mediterranean climatic conditions of the Western Cape province, the Swartland region is intensively cropped, producing spring wheat (Triticum aestivum L.), but due to ryegrass competition, yield is reduced. In addition, ryegrass has developed resistance to herbicides. This necessitates the use of integrated weed ...

  3. Economic evaluation of a crop rotation portfolio for irrigated farms in central Chile

    Directory of Open Access Journals (Sweden)

    Jorge González U

    2013-09-01

    Full Text Available The sustainable use of productive resources by agricultural producers in the central valley of Chile should be compatible with economic results so that producers can select an appropriate rotation or succession of annual crops and pasture. The objective of this work was to evaluate the economic behavior of four food crop and supplementary forage rotations using indicators of profitability and profit variability. Productive data were used from a long-term experiment (16 yr in the central valley of Chile under conditions of irrigation. With productive data and information on historic input/output prices, the real net margin per rotation (RNMR and its coefficient of variation (CV were determined. The results indicated that the highest economic benefits and greatest economic stability were obtained with rotations that only included crops, namely sugar beet (Beta vulgaris L. subsp. vulgaris-wheat (Triticum aestivum L.-bean (Phaseolus vulgaris L.-barley (Hordeum vulgare L. (CR2 and corn (Zea mays L.-wheat-bean-barley (CR4. These rotations included crops with low CV of the net margin, such as wheat, barley and beans, with values between 0.31 and 0.34. The rotations with crops and pasture, sugar beet-wheat-red clover (Trifolium pratense L. (2 (CR1 and corn-wheat-red clover (2 (CR3 had lower net margins and more variability of this indicator. Red clover had the highest CV value (1.00. The selection of crops for rotations and their sequence were determining factors in the economic behavior of rotations, affecting the level of RNMR and the degree of inter-annual variability of this indicator. Thus, differences among rotations of 47% in net margin were determined (CR2 vs. CR1, which only differed in the replacement of pasture with red clover (2 by bean-barley. The economic analysis based on the net margin and its variability allow for discriminating among rotations, providing valuable information for producers in deciding which crops to use in rotations.

  4. PRACT (Prototyping Rotation and Association with Cover crop and no Till) - a tool for designing conservation agriculture systems

    NARCIS (Netherlands)

    Naudin, K.; Husson, M.O.; Scopel, E.; Auzoux, S.; Giller, K.E.

    2015-01-01

    Moving to more agroecological cropping systems implies deep changes in the organization of cropping systems. We propose a method for formalizing the process of innovating cropping system prototype design using a tool called PRACT (Prototyping Rotation and Association with Cover crop and no Till)

  5. 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.

  6. [Effects of crop rotation and bio-organic manure on soil microbial characteristics of Chrysanthemum cropping system].

    Science.gov (United States)

    Xiao, Xin; Zhu, Wei; Du, Chao; Shi, Ya-dong; Wang, Jian-fei

    2015-06-01

    We conducted a field experiment to evaluate the effects of rotation system and bio-organic manure on soil microbial characteristics of Chrysanthemum cropping system. Taking Chrysanthemum morifolium Ramat and wheat as experimental plants, treatments under Chrysanthemum continuous cropping system (M1), conventional Chrysanthemum-wheat rotation system (M2), and Chrysanthemum-wheat rotation system receiving bio-organic manure application of 200 kg · 667 m(-2) (M3) were designed. Soil chemical properties, soil microbial biomass carbon (MBC) and nitrogen (MBN), and the amounts of different types of soil microorganisms were determined. Results showed that compared with M1, treatments of M2 and M3 significantly increased soil pH, organic matter, available N, P, and K, MBC, MBN, and the amounts of bacteria, fungi and actinomycetes, but decreased the ratio of MBC/MBN, and the relative percentage of fungi in the total amount of microorganisms. Treatment of M3 had the highest contents of soil organic matter, available N, available P, available K, MBC, MBN, and the amounts of bacteria, fungi and actinomycetes, with the values being 15.62 g · kg(-1), 64.75 mg · kg(-1), 83.26 mg · kg(-1), 96.72 mg · kg(-1), 217.40 mg · kg(-1), 38.41 mg · kg(-1), 22.31 x 10(6) cfu · g(-1), 56.36 x 10(3) cfu · g(-1), 15.90 x 10(5) cfu · g(-1), respectively. We concluded that rational crop rotation and bio-organic manure application could weaken soil acidification, improve soil fertility and microbial community structure, increase the efficiency of nutrition supply, and have a positive effect on reducing the obstacles of continuous cropping.

  7. Precipitation partitioning in short rotation bioenergy crops: implications for downstream water availability.

    Science.gov (United States)

    Peter Caldwell; Chelcy F. Miniat; Doug Aubrey; Rhett Jackson; Jeff McDonnell; Ken W. Krauss; James S. Latimer

    2016-01-01

    The southern United States is a potential leader in producing biofuels from intensively managed, short rotation (8–12 years) woody crops such as southern pines, and native and non-native hardwoods. However, their accelerated development under intensive management has raised concerns that fast-growing bioenergy crops could reduce recharge to stream flows and groundwater...

  8. Performance of process-based models for simulation of grain N in crop rotations across Europe

    Czech Academy of Sciences Publication Activity Database

    Xiaogang, Y.; Kesebaum, K. C.; Kollas, C.; Manevski, K.; Baby, S.; Beaudoin, N.; Öztürk, I.; Gaiser, T.; Wu, L.; Hoffmann, M.; Charfeddine, M.; Conradt, T.; Constantin, J.; Ewert, F.; de Cortazar-Atauri, I. G.; Giglio, L.; Hlavinka, Petr; Hoffmann, H.; Launay, M.; Louarn, G.; Manderscheid, R.; Mary, B.; Mirschel, W.; Nendel, C.; Pacholski, A.; Palouso, T.; Ripoche-Wachter, D.; Rötter, R. P.; Ruget, F.; Sharif, B.; Trnka, Miroslav; Ventrella, D.; Weigel, H-J.; Olesen, J. E.

    2017-01-01

    Roč. 154, JUN (2017), s. 63-77 ISSN 0308-521X R&D Projects: GA MŠk(CZ) LO1415; GA MZe QJ1310123 Institutional support: RVO:67179843 Keywords : Calibration * Crop model * Crop rotation * Grain N content * Model evaluation * Model initialization Subject RIV: EH - Ecology, Behaviour OBOR OECD: Environmental sciences (social aspects to be 5.7) Impact factor: 2.571, year: 2016

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

    International Nuclear Information System (INIS)

    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

  10. Soil organic carbon dynamics in typical durum wheat-based crop rotations of Southern Italy

    Directory of Open Access Journals (Sweden)

    Claudia Di Bene

    2016-08-01

    Full Text Available Mediterranean agricultural areas are dominated by cropping systems based on winter cereals crops, summer irrigated crops, foragebased systems, and mixed succession with bare fallow. Soil organic carbon (SOC is widely used to assess the environmental performance of these cropping systems, since it is strongly influenced by management practices and environmental conditions. This study evaluates the sustainability of representative intensive cropping systems of Southern Italy, in terms of SOC stock changes and CO2 emissions in the long-term perspective, using a process-based model (RothC10N combined with a GIS-based spatialization procedure. On the basis of SOC modelling, results showed that crop management practices currently adopted by farmers did not guarantee SOC sequestration in all the rotations (–4.29 Mg C ha–1. The sustainability of cropping systems can be improved through management practices such as the retention of crop residues into the field and/or the rational use of irrigation for the summer crop (6.73 Mg C ha–1. This finding could help policy makers to provide suggestions for a more effective local implementation of agro-environmental measures.

  11. 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

    Nitrogen (N) supply in stockless organic farming may be improved through use of grass-clover for anaerobic digestion, producing biogas and digested manure for use as fertilizer in the crop rotation. We studied the effects of grass-clover management on N cycling, nitrous oxide (N2O) emissions...... 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...... in the rotation (spring barley, potato and winter wheat); actual digestion of grass-clover cuttings was not possible, instead digested pig manure was used as substitute for digested grass-clover. Nitrous oxide fluxes were monitored between April 2008 and May 2009. In general, application of digested manure had...

  12. Evaluation of soil quality indicators in paddy soils under different crop rotation systems

    Science.gov (United States)

    Nadimi-Goki, Mandana; Bini, Claudio; Haefele, Stephan; Abooei, Monireh

    2013-04-01

    Evaluation of soil quality indicators in paddy soils under different crop rotation systems Soil quality, by definition, reflects the capacity to sustain plant and animal productivity, maintain or enhance water and air quality, and promote plant and animal health. Soil quality assessment is an essential issue in soil management for agriculture and natural resource protection. This study was conducted to detect the effects of four crop rotation systems (rice-rice-rice, soya-rice-rice, fallow-rice and pea-soya-rice) on soil quality indicators (soil moisture, porosity, bulk density, water-filled pore space, pH, extractable P, CEC, OC, OM, microbial respiration, active carbon) in paddy soils of Verona area, Northern Italy. Four adjacent plots which managed almost similarly, over five years were selected. Surface soil samples were collected from each four rotation systems in four times, during growing season. Each soil sample was a composite of sub-samples taken from 3 points within 350 m2 of agricultural land. A total of 48 samples were air-dried and passed through 2mm sieve, for some chemical, biological, and physical measurements. Statistical analysis was done using SPSS. Statistical results revealed that frequency distribution of most data was normal. The lowest CV% was related to pH. Analysis of variance (ANOVA) and comparison test showed that there are significant differences in soil quality indicators among crop rotation systems and sampling times. Results of multivariable regression analysis revealed that soil respiration had positively correlation coefficient with soil organic matter, soil moisture and cation exchange capacity. Overall results indicated that the rice rotation with legumes such as bean and soybean improved soil quality over a long time in comparison to rice-fallow rotation, and this is reflected in rice yield. Keywords: Soil quality, Crop Rotation System, Paddy Soils, Italy

  13. Species composition and density of weeds in a wheat crop depending on the soil tillage system in crop rotation

    Directory of Open Access Journals (Sweden)

    P. Yankov

    2015-03-01

    Full Text Available Abstract. The investigation was carried out in the trial field of Dobrudzha Agricultural Institute, General Toshevo on slightly leached chernozem soil type. For the purposes of this investigation, variants from a stationary field experiment initiated in 1987 and based on various soil tillage tools and operations were analyzed. The species composition and density of weeds were followed in a wheat crop grown after grain maize using the following soil tillage systems: plowing at 24 – 26 cm (for maize – disking at 10 – 12 cm (for wheat; cutting at 24 – 26 cm (for maize – cutting at 8 – 10 cm (for wheat; disking at 10 – 12 cm (for maize – disking at 10 – 12 cm (for wheat; no-tillage (for maize – no-tillage (for wheat.Weed infestation was read at the fourth rotation since the initiation of the trial. The observations were made in spring before treatment of the crop with herbicides. The soil tillage system had a significant effect on the species composition and density of weeds in the field with wheat grown after previous crop maize. The long-term alternation of plowing with disking in parallel with the usage of chemicals for weed control lead to lower weed infestation of the weed crop. The lower weed density after this soil tillage system was not related to changes in the species composition and the relative percent of the individual species in the total weed infestation. The long-term application in crop rotation of systems without turning of the soil layer and of minimal and no-tillage increased the amount of weeds. The reason is the greater variability of weed species which typically occur after shallow soil tillage.

  14. Effect of no-tillage crop rotation systems on nutrient status of a rhodic ...

    African Journals Online (AJOL)

    The rotation crops, mucuna (Mucuna aterrima Piper&Tracy), cajanus (Cajanus cajan (L.) Millsp, rye (Secale cereale L)., oat (Avena sativa L.), pisum (Pisum sativum L.), wheat (Triticum aestivum L.), crotolaria (Crotolaria juncea L.), and black oats (Avena strigosa Scheib), were planted in winter whereas maize and soybean ...

  15. Effect of no-tillage crop rotation systems on nutrient status of a rhodic ...

    African Journals Online (AJOL)

    In this study the effects of no-tillage and eight crop rotations (established in 1985) on chemical properties of a Rhodic Ferralsol (Typic Haplorthox, Soil Taxonomy) and on nutrient uptake by maize (Zea mays L.) and soybean (Glycine max L. Merrill) leaves were assessed in the state of São Paulo, Brazil, using a randomized ...

  16. Supporting Agricultural Ecosystem Services through the Integration of Perennial Polycultures into Crop Rotations

    Directory of Open Access Journals (Sweden)

    Peter Weißhuhn

    2017-12-01

    Full Text Available This review analyzes the potential role and long-term effects of field perennial polycultures (mixtures in agricultural systems, with the aim of reducing the trade-offs between provisioning and regulating ecosystem services. First, crop rotations are identified as a suitable tool for the assessment of the long-term effects of perennial polycultures on ecosystem services, which are not visible at the single-crop level. Second, the ability of perennial polycultures to support ecosystem services when used in crop rotations is quantified through eight agricultural ecosystem services. Legume–grass mixtures and wildflower mixtures are used as examples of perennial polycultures, and compared with silage maize as a typical crop for biomass production. Perennial polycultures enhance soil fertility, soil protection, climate regulation, pollination, pest and weed control, and landscape aesthetics compared with maize. They also score lower for biomass production compared with maize, which confirms the trade-off between provisioning and regulating ecosystem services. However, the additional positive factors provided by perennial polycultures, such as reduced costs for mineral fertilizer, pesticides, and soil tillage, and a significant preceding crop effect that increases the yields of subsequent crops, should be taken into account. However, a full assessment of agricultural ecosystem services requires a more holistic analysis that is beyond the capabilities of current frameworks.

  17. Environmental enchancement using short-rotation tree crops: research results and directions

    Energy Technology Data Exchange (ETDEWEB)

    Tolbert, V.R.; Schiller, A.

    1996-10-01

    Short-rotation woody crops (SRWC) and perennial grasses used as biomass feedstocks for energy and fiber can provide multiple economic and environmental benefits. Site-specific environmental studies are providing information needed to help evaluate the economic and environmental impacts of biomass production at both local and regional scales. Erosion and chemical movement from an annual row crop, switchgrass, and tree crop with and without a groundcover are being compared in the Southeast. Studies of SRWC productivity on the South Carolina coastal plain are comparing surface and subsurface movement of chemicals applied under different fertilization and irrigation regimes, and addressing use of mill and agricultural residues to enhance crop production. Results are helping to assess the effects of biomass crops produced on different principal soil types and to match tree species with appropriate sites to maximize productivity and minimize environmental impacts. Studies are comparing wildlife use of biomass crops to row crops, grasslands, and natural forests. Results to date show that SRWCs support greater bird diversity than row crops, but less than natural forests; switchgrass plantings extend habitat for grasslands birds. Collaboration with an industrial partner on diverse SRWC plantings in the Southeast is addressing the relationship between plantings of different acreage, age, tree species, and landscape context and breeding bird use. Information from wildlife diversity, water, and soil quality studies can be used by the Biofuels Feedstock Development Program (BFDP), researchers, producers, and industry to identify management strategies to maintain productivity While enhancing the environment.

  18. Silviculture and biology of short-rotation woody crops in temperate regions: Then and now

    Energy Technology Data Exchange (ETDEWEB)

    Dickmann, Donald I. [Department of Forestry, Michigan State University, East Lansing, MI 48824-1222 (United States)

    2006-08-15

    Although its roots are in antiquity, the current concept of short-rotation woody crops (SRWC) for fiber and energy evolved scientifically from pioneering tree breeding work begun in the early 20th century. A natural outgrowth of this work was the culture of fast-growing trees on rotations of 1-15 years. Close-spaced tree culture received further impetus with the introduction of the 'silage sycamore' concept in the southeastern US in the mid-1960s and the OPEC oil embargo in 1973, leading to statistically designed trials at numerous locations in North America, Europe, and Scandinavia. Early silvicultural research focused on spacing and species trials, propagation methods, site preparation, weed management, nutrition, growth, and yield. Because these trials were based on small plots, and the importance of pest depredations or site variation were not fully recognized, early biomass yield predictions tended to be overly optimistic. Soon physiologists and ecologists began to unravel the biological characteristics of SRWC plantations and their responses to environment. Knowledge of the influence and diversity of pests-insects, diseases, and animals-provided a necessary reality check. Many hardwood tree species and a few conifers have been evaluated over the years for SRWC in temperate regions of the world. Clones of Populus and Salix, however, became the dominant plantation material because of their inherently rapid growth and ease of propagation by hardwood cuttings. Among conifers, loblolly pine (Pinus taeda) also shows promise. Because genetic variation is readily exploitable in the dominant SRWC taxa, strongly focused breeding programs began to provide highly productive genotypes and seed sources in the last decades of the 20th century. A new plateau, with significant practical potential, was reached in the late 20th century when biotechnological methods were applied to tree taxa. Recently, the DNA in the Populus genome was sequenced. Thus, the few current

  19. Perennial Grass Based Crop Rotations in Virginia: Effects on Soil Quality, Disease Incidence, and Cotton and Peanut Growth.

    OpenAIRE

    Weeks, Jr., James Michael

    2008-01-01

    In 2003 eight peanut and cotton crop rotations were established in southeastern Virginia, 4 of which included 2 or 3 years of tall fescue or orchardgrass grown as high-value hay crops. Each crop rotation was evaluated for changes in soil quality indicators including soil carbon and nitrogen, water stable soil aggregates, plant available water content, bulk density, cone index values, and soil moisture. Cotton and peanut growth and yield were also observed to evaluate ch...

  20. Evaluation of the Effect of Crop Rotations on Yield and Yield Components of Bread Wheat (Triticum aestivum L. cv. Darya)

    OpenAIRE

    H. A. Fallahi; U. Mahmadyarov; H. Sabouri; M. Ezat-Ahmadi4

    2013-01-01

    Grain yield in wheat is influenced directly and indirectly by other plant characteristics. One of the main goals in wheat breeding programs is increase of grain yield. Considering the role of crop rotation in increasing grain yield, and in order to study the difference between crop rotations for wheat yield and yield components (Darya cultivar), an experiment was conducted with six rotation treatments (wheat-chickpea-wheat, wheat-cotton-wheat, wheat-watermelon-wheat, wheat-wheat-wheat, wheat-...

  1. Decoupling the deep: crop rotations, fertilization and soil physico-chemical properties down the profile

    Science.gov (United States)

    Hobley, Eleanor; Honermeier, Bernd; Don, Axel; Amelung, Wulf; Kögel-Knabner, Ingrid

    2017-04-01

    Crop fertilization provides vital plant nutrients (e.g. NPK) to ensure yield security but is also associated with negative environmental impacts. In particular, inorganic, mineral nitrogen (Nmin) fertilization leads to emissions during its energy intensive production as well as Nmin leaching to receiving waters. Incorporating legumes into crop rotations can provide organic N to the soil and subsequent crops, reducing the need for mineral N fertilizer and its negative environmental impacts. An added bonus is the potential to enhance soil organic carbon stocks, thereby reducing atmospheric CO2 concentrations. In this study we assessed the effects of legumes in rotation and fertilization regimes on the depth distribution - down to 1 m - of total soil nitrogen (Ntot), soil organic carbon (SOC) as well as isotopic composition (δ13C, δ15N), electrical conductivity and bulk density as well as agricultural yields at a long-term field experiment in Gießen, Germany. Fertilization had significant but small impacts on the soil chemical environment, most particularly the salt content of the soil, with PK fertilization increasing electrical conductivity throughout the soil profile. Similarly, fertilization resulted in a small reduction of soil pH throughout the soil profile. N fertilization, in particular, significantly increased yields, whereas PK fertilizer had only marginal yield effects, indicating that these systems are N limited. This N limitation was confirmed by significant yield benefits with leguminous crops in rotation, even in combination with mineral N fertilizer. The soil was physically and chemically influenced by the choice of crop rotation. Adding clover as a green mulch crop once every 4 years resulted in an enrichment of total N and SOC at the surface compared with fava beans and maize, but only in combination with PK fertilization. In contrast, fava beans and to a lesser extent maize in rotation lowered bulk densities in the subsoil compared with clover

  2. Does crop rotational diversity increase soil microbial resistance and resilience to drought and flooding?

    Science.gov (United States)

    Schnecker, Jörg; Calderon, Francisco; Cavigelli, Michel; Lehman, Michael; Tiemann, Lisa; Grandy, Stuart

    2017-04-01

    Future climate scenarios indicate more frequent and stronger extreme weather events. This includes more severe droughts but also an increase in heavy rain events and flooding. Agricultural systems are of special interest in this context because of their role in food security but also because of their potentially changing role in global carbon and nutrient cycling under these extreme conditions. Plant diversification strategies like more complex crop rotations which support more diverse soil microbial communities with higher functional redundancy might be more resistant to drought and flooding and could help to reduce impacts on microbial carbon and nutrient cycling. To test how crop diversification affects the response of soil microbial processes to drought and flooding and reoccurring drought and flooding, we manipulated water regimes in lab incubation experiments using soils from four long term rotation experiments across the USA, including a low (one or two crops) vs. high (>3 crops) diversity rotations at each site. The sites range from low precipitation (Colorado), over intermediate precipitation (Michigan and South Dakota) to high precipitation in Maryland. Replicate sets of samples were either allowed to dry out, were gradually flooded or kept at a constant water content (control). We monitored CO2 production during five stress cycles. Additionally, we determined microbial biomass, enzyme activities and N pools during the first and last stress cycle in soils from the precipitation extremes. After a total incubation length of 165 days and five stress cycles only the soils from short rotations in Maryland and South Dakota that had been subjected to reoccurring drought showed significantly less cumulative CO2 loss compared to their respective controls. All the other sites and rotation length did not significantly differ from control when subjected to reoccurring drought or flooding. A Principal component analysis using all measured parameters of Colorado and

  3. Differences in crop bacterial community structure between hoatzins from different geographical locations.

    Science.gov (United States)

    Godoy-Vitorino, Filipa; Leal, Sara J; Díaz, Wilmer A; Rosales, Judith; Goldfarb, Katherine C; García-Amado, María A; Michelangeli, Fabían; Brodie, Eoin L; Domínguez-Bello, María G

    2012-04-01

    The hoatzin is the only known folivorous bird with foregut fermentation, and is distributed in Venezuela in rivers of the central savannas to the eastern Orinoco River. Differences in diet are expected to affect the digestive microbiota and we hypothesized that hoatzins from different habitats might have a different crop microbiota. We thus characterized the microbiota of six birds from the Cojedes and Orinoco Rivers using the G2 PhyloChip and, in parallel, we compared plant availability and foraging behavior of the hoatzins from the two locations. Plant composition differed between the 2 locations, which shared 5 out of 18 plant families and 1 plant genus--Coccoloba--that was highly consumed in both locations. The PhyloChip detected ∼1600 phylotypes from 42 phyla. There was a core microbiota with ~50% of the OTUs shared by at least 4 of the 6 individuals, but there were also differences in the crop microbiota of animals from the two regions. There existed a higher relative abundance of Alphaproteobacteria and Actinobacteria in the crops of birds from the Cojedes River and of Clostridia and Deltaproteobacteria in the crops of birds from the Orinoco River. The results showed both a core crop microbiota and also the bacterial taxa responsible for geographical differences among individuals from the two locations with different vegetation, suggesting an effect of both diet and geography in shaping the crop bacterial community of the hoatzin. Copyright © 2012 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  4. 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

    Two different modeling approaches were used to simulate the N leached during an intensively fertigated crop rotation: a recently developed crop-based simulation model (EU-Rotate_N) and a widely recognized solute transport model (Hydrus-2D). Model performance was evaluated using data from an exper......-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...

  5. CO2 fluxes exchanged by a 4-year crop rotation cycle.

    Science.gov (United States)

    Aubinet, M.; Moureaux, C.; Bodson, B.; Dufranne, D.; Heinesch, B.; Suleau, M.; Vancutsem, F.; Vilret, A.

    2009-04-01

    This study analyses carbon fluxes exchanged by a production crop during a four year cycle. Between 2004 and 2008, the successive crops were sugar beet, winter wheat, potato and again winter wheat. Eddy covariance, automatic and manual soil chamber, leaf diffusion and biomass measurements were performed continuously in order to obtain the daily and seasonal Net Ecosystem Exchange (NEE), Gross Primary Productivity (GPP), Total Ecosystem Respiration (TER), Net Primary Productivity (NPP), Autotrophic Respiration, Heterotrophic Respiration and Net Biome Production (NBP). The whole cycle budget showed that NEE was negative and the rotation behaved as a sink of 1.59 kgC m-2 over the 4-year rotation. However, if exports were deducted from the budget, the crop would become a small source of 0.22 (+/- 0.14) kgC m-2, which also suggests that the crop soil carbon content decreased. This could partly be explained by the crop management, as neither farmyard manure nor slurry had been applied to the crop for more than 10 years and as cereal straw had been systematically exported for livestock. This result is also strongly dependent on climate: the fluxes were subjected to a large inter-annual variability due to differences between crops but also to climate variability. In particular, the mild winter and the dry spring underwent in 2007 induced an increase of the biomass fraction that returned to the soil, at the expense of harvested biomass. If 2007 had been a ‘normal' year, the carbon emission by the crop rotation would have been twice as great. This is analysed more in detail in a companion presentation (Dufranne et al., this session). The impacts of some farmer interventions were quantified. In particular, the impact of ploughing was found to be limited both in intensity (1 to 2 micromol m-2 s-1) and duration (not more than 1 day). Seasonal budgets showed that, during cropping periods, the TER/GPP ratio varied between 40 and 60% and that TER was dominated mainly by the

  6. Vertical distribution and composition of weed seeds within the plough layer after eleven years of contrasting crop rotation and tillage schemes

    DEFF Research Database (Denmark)

    Scherner, Ananda; Melander, Bo; Kudsk, Per

    2016-01-01

    flora was recorded each year and the content and vertical location of individual weed seeds within the plough layer (0–20 cm) were determined after 11 years of continuous mouldboard ploughing (P), pre-sowing tine cultivation to 8–10 cm soil depth (H8-10) and direct drilling (D). The content of weed......Tillage methods and crop rotation are probably the two most important cropping factors affecting weed communities, particularly when herbicide use is restricted. This study examined weed dynamics following eleven years of different tillage and crop rotation treatments. The aboveground grass weed...... seeds, especially grass weeds, was determined for three distinct soil layers (0–5, 5–10 and 10–20 cm), reflecting the cultivation depths of the tillage treatments. The annual grass weeds, Apera spica-venti and Vulpia myuros, were promoted by non-inversion tillage and in the case of V. myuros also...

  7. 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.

  8. 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.

  9. 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.

  10. 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....

  11. Tropical Legume Crop Rotation and Nitrogen Fertilizer Effects on Agronomic and Nitrogen Efficiency of Rice

    Directory of Open Access Journals (Sweden)

    Motior M. Rahman

    2014-01-01

    Full Text Available 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.

  12. A Data-driven Approach to Integrate Crop Rotation Agronomic Practices in a Global Gridded Land-use Forcing Dataset

    Science.gov (United States)

    Sahajpal, R.; Hurtt, G. C.; Chini, L. P.; Frolking, S. E.; Izaurralde, R. C.

    2016-12-01

    Agro-ecosystems are the dominant land-use type on Earth, covering more than a third of ice-free land surface. Agricultural practices have influenced the Earth's climate system by significantly altering the biogeophysical and biogeochemical properties from hyper-local to global scales. While past work has focused largely on characterizing the effects of net land cover changes, the magnitude and nature of gross transitions and agricultural management practices on climate remains highly uncertain. To address this issue, a new set of global gridded land-use forcing datasets (LUH2) have been developed in a standard format required by climate models for CMIP6. For the first time, this dataset includes information on key agricultural management practices including crop rotations. Crop rotations describe the practice of growing crops on the same land in sequential seasons and are essential to agronomic management as they influence key ecosystem services such as crop yields, water quality, carbon and nutrient cycling, pest and disease control. Here, we present a data-driven approach to infer crop rotations based on crop specific land cover data, derived from moderate resolution satellite imagery and created at an annual time-step for the continental United States. Our approach compresses the more than 100,000 unique crop rotations prevalent in the United States from 2013 - 2015 to about 200 representative crop rotations that account for nearly 80% of the spatio-temporal variability. Further simplification is achieved by mapping individual crops to crop functional types, which identify crops based on their photosynthetic pathways (C3/C4), life strategy (annual/perennial) and whether they are N-fixing or not. The resulting matrix of annual transitions between crop functional types averages 41,000 km2/yr for rotations between C3 and C4 annual crops, and 140,000 km2/yr between C3 N-fixing and C4 annual crops. The crop rotation matrix is combined with information on other land

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

    Directory of Open Access Journals (Sweden)

    Rongyan Bu

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

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

    Science.gov (United States)

    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.

  15. 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

    structural quality was visually evaluated early June and mid October. Minimal disturbed soil cores early June and these were used for X-ray CT scanning and more traditional analysis. Soil friability was determined on the soil samples using a drop shatter test. Crop yield was determined and correlated...... to the soil quality estimates. We found significant effect of both rotation and tillage on visual soil structure at both times of assessment. Poor soil structure was found for NT except when combined with a versatile crop rotation (R6). The soil core pore characteristics data also displayed a significant...... effect of tillage but only a weak insignificant effect of rotation. The drop shatter results were in accordance with the visual assessment data. Crop yield correlated significantly with the visual soil structure scores. We conclude that a versatile crop rotation was needed for an optimal performance...

  16. Carbon balance of the typical grain crop rotation in Moscow region assessed by eddy covariance method

    Science.gov (United States)

    Meshalkina, Joulia; Yaroslavtsev, Alexis; Vassenev, Ivan

    2017-04-01

    Croplands could have equal or even greater net ecosystem production than several natural ecosystems (Hollinger et al., 2004), so agriculture plays a substantial role in mitigation strategies for the reduction of carbon dioxide emissions. In Central Russia, where agricultural soils carbon loses are 9 time higher than natural (forest's) soils ones (Stolbovoi, 2002), the reduction of carbon dioxide emissions in agroecosystems must be the central focus of the scientific efforts. Although the balance of the CO2 mostly attributed to management practices, limited information exists regarding the crop rotation overall as potential of C sequestration. In this study, we present data on carbon balance of the typical grain crop rotation in Moscow region followed for 4 years by measuring CO2 fluxes by paired eddy covariance stations (EC). The study was conducted at the Precision Farming Experimental Fields of the Russian Timiryazev State Agricultural University, Moscow, Russia. The experimental site has a temperate and continental climate and situated in south taiga zone with Arable Sod-Podzoluvisols (Albeluvisols Umbric). Two fields of the four-course rotation were studied in 2013-2016. Crop rotation included winter wheat (Triticum sativum L.), barley (Hordeum vulgare L.), potato crop (Solanum tuberosum L.) and cereal-legume mixture (Vicia sativa L. and Avena sativa L.). Crops sowing occurred during the period from mid-April to mid-May depending on weather conditions. Winter wheat was sown in the very beginning of September and the next year it occurred from under the snow in the phase of tillering. White mustard (Sinapis alba) was sown for green manure after harvesting winter wheat in mid of July. Barley was harvested in mid of August, potato crop was harvested in September. Cereal-legume mixture on herbage was collected depending on the weather from early July to mid-August. Carbon uptake (NEE negative values) was registered only for the fields with winter wheat and white

  17. [A long-term experiment on the complex influence of cultivating, fertilizing, and crop rotation measures on humic substances in soil and development of yield (author's transl)].

    Science.gov (United States)

    Heisig, W; Müller, G; Völker, U

    1977-01-01

    In a 10-year field experiment, the influence of fertilizing, cultivating, and crop rotation measures on the C-content of the soil, humus quality of the organic soil substance, and the yield was investigated. With cultivation of fodder plants only, the C-content of the soil can be improved by increased mineral and increased organo-mineral fertilization at any depth of cultivation. When in the same location there was a turn between cereals and green crops, a decrease of C-rate can only be prevented by increased organo-mineral fertilization. Continuous cultivation of root crops resulted in a decrease of the C-content. Deeper tillage of the soil generally decreased C-content. Within the years, a variability of the pure humin substances could be detected, depending on the rotation of crops and C-content. The composition of the fulvic acids is differentiated in dependence on the factors "time" and "cultivation". The effect of fertilization variants on the yield was different. Fertilization in that location with manure only, compared with mineral fertilization, caused in most cases depression in yield. Decrease on yield by deeper ploughing had the least influence with root crops.

  18. THE NUTRIENTS BALANCE OF CROP ROTATION AS AN INDICATOR OF SUSTAINABLE FARMING ON ARABLE LAND

    Directory of Open Access Journals (Sweden)

    Eva Hanáčková

    2009-03-01

    Full Text Available The nutrient balance of five crop rotation systems under conventional and minimal tillage with interaction of different fertilization treatments was investigated at the experimental station of Slovak Agricultural University in Nitra Dolná Malanta, during 2004-2005. The five-field crop rotation of maize (Zea mays L. - winter wheat (Triticum aestivum L. - spring barley (Hordeum vulgare L. underseeded with red clover - red clover (Trifolium pratense - common pea (Pisum sativum L. and mustard as catch crop was used. The most serious deficit of nitrogen (- 62.2 kg.ha-1.yr-1, phosphorus (- 24.0 kg.ha-1.yr-1 and potassium (- 89.2 kg.ha-1.yr-1 was on control treatments. Deficit of nitrogen was also found-out in treatments with mineral fertilizers application. However higher deficit of nitrogen (- 25.4 kg.ha-1.yr- 1 was registered under conventional tillage. In treatment fertilized with mineral fertilizers together with by - product of pre - crop incorporation into soil (PZ, small balance surplus of nitrogen (8 kg.ha-1.yr-1 - B1, 11.5 kg. ha-1.yr-1 - B2, respectively was calculated. The positive balance of phosphorus achieved in treatments with into soil incorporated by - products of pre - crops (in both systems of soil cultivation amounting value of 3.9 kg.ha-1.yr-1 can contribute to good supply of phosphorous in soil. The negative balance of potassium fluctuating from - 89.2 kg.ha-1.yr-1 (control treatment to - 22 kg.ha-1.yr-1 (PZ is acceptable owing to high content of available potassium in soil of experimental stand.

  19. Problems Associated with Crop Rotation for Management of Pratylenchus penetrans on Easter Lily.

    Science.gov (United States)

    Westerdahl, B B; Giraud, D; Etter, S; Riddle, L J; Anderson, C A

    1998-12-01

    In Humboldt and Del Norte counties of California and Curry County, Oregon, Easter lilies (Lilium longiflotum) are grown commercially in a 3- to 6-year rotation with pasture for cattle and sheep. Bulbs are sold to greenhouse operations to produce flowering plants. The lesion nematode, Pratylenchus penetrans, is a serious detriment to Easter lily production. Both soil and planting stock are often infested; typically, a dual nematicide application is used consisting of a preplant soil fumigation followed by an at-planting application of an organophosphate or carbamate. Nematicide usage has resulted in ground-water contamination. Several factors that could lead to an improved crop rotation program were examined in five field trials in Oregon. Examining the relative nematode host status of crops for feeding cattle and sheep indicated differences in host suitability among clovers and fescues that could prove useful in development of pasture mixes. Populations of P. penetrans under continuous fallow and pasture were monitored for 4 years following harvest of Easter lilies. Populations fluctuated in both situations but generally increased on pasture plants and decreased under fallow. Nematodes were still detectable at the end of 4 years of weed-free fallow. Populations of P. penetrans on Easter lilies were followed over two successive crops. Numbers in soil peaked in July and then decreased while numbers within roots continued to increase until harvest in October.

  20. 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

  1. A STELLA model to estimate water and nitrogen dynamics in a short-rotation woody crop plantation

    Science.gov (United States)

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

    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., NH4...

  2. Nitrous oxide and carbon dioxide emissions from monoculture and rotational cropping of corn, soybean and winter wheat

    International Nuclear Information System (INIS)

    Drury, C.F.; Yang, X.M.; Reynolds, W.D.; McLaughlin, N.B.

    2008-01-01

    Nitrous oxide (N 2 O) and carbon dioxide (CO 2 ) emissions from agricultural soils are influenced by different types of crops, the amounts and types of nitrogen fertilizers used, and the soil and climatic conditions under which the crops are grown. Crop rotation also has an impact on N 2 O emissions, as the crop residues used to supply soluble carbon to soil biota often differ from the crops being grown. This study compared the influence of crops and residues from preceding crops on N 2 O and CO 2 emissions from monoculture crops of soybeans, corn, and winter wheat at a site in Ontario. The phases of different rotations were compared with 2- and 3-year crop rotations. Results of the study showed that N 2 O emissions were approximately 3.1 to 5.1 times higher in monoculture corn than levels observed in winter wheat or soybean crops. When corn followed corn, average N 2 O emissions twice as high as when corn followed soybeans, and 65 per cent higher than when corn followed winter wheat. The higher levels of both N 2 O and CO 2 were attributed to higher inorganic nitrogen (N) application rates in corn crops. In the corn phase, CO 2 levels were higher when the preceding crop was winter wheat. It was concluded that N 2 O and CO 2 emissions from agricultural fields are influenced by both current and preceding crops, a fact which should be considered and accounted for in estimates and forecasts of agricultural greenhouse gas (GHG) emissions. 21 refs., 3 tabs., 10 figs

  3. Biological nitrogen fixation in three long-term organic and conventional arable crop rotation experiments in Denmark

    DEFF Research Database (Denmark)

    Pandey, Arjun; Li, Fucui; Askegaard, Margrethe

    2017-01-01

    Biological nitrogen (N) fixation (BNF) by legumes in organic cropping systems has been perceived as a strategy to substitute N import from conventional sources. However, the N contribution by legumes varies considerably depending on legumes species, as well as local soil and climatic conditions...... of legumes. Therefore, this study aimed to estimate BNF in long-term experiments with a range of organic and conventional arable crop rotations at three sites in Denmark varying in climate and soils (coarse sand, loamy sand and sandy loam) and to identify possible causes of differences in the amount of BNF....... The experiment included 4-year crop rotations with three treatment factors in a factorial design: (i) rotations, i.e. organic with a year of grass-clover (OGC), organic with a year of grain legumes (OGL), and conventional with a year of grain legumes (CGL), (ii) with (+CC) and without (−CC) cover crops, and (iii...

  4. Stability control of grasping objects with different locations of center of mass and rotational inertia.

    Science.gov (United States)

    Slota, Gregory P; Suh, Moon Suk; Latash, Mark L; Zatsiorsky, Vladimir M

    2012-01-01

    The objective of this study was to observe how the digits of the hand adjust to varying location of the center of mass (CoM) above or below the grasp and rotational inertia (RI) of a handheld object. Such manipulations do not immediately affect the equilibrium equations while stability control is affected. Participants were instructed to hold a handle, instrumented with 5 force-torque transducers and a 3-D rotational tilt sensor, while either the location of the CoM or the RI values were adjusted. On the whole, people use 2 mechanisms to adjust to the changed stability requirements; they increase the grip force and redistribute the total moment between the normal and tangential forces offsetting internal torques. The increase in grip force, an internal force, and offsetting internal torques allows for increases in joint and hand rotational apparent stiffness while not creating external forces-torques that would unbalance the equations of equilibrium.

  5. 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

  6. [Effect of Crop Rotation and Biological Manure on Quality and Yield of "Chuju" Chrysanthemum morifolium and Continuous Cropping Soil Enzyme Activities].

    Science.gov (United States)

    Xiao, Xin; Zhu, Wei; Du, Chao; Shi, Ya-dong; Wang, Jian-fei

    2015-05-01

    To investigate the effects of chrysanthemum-wheat rotation system and biological manure on continuous cropping soil enzyme activities and quality and yield of Chrysanthemum morifolium. Field experiments were conducted at the research base of Anhui Jutai Chuju Chrysanthemum morifolium Herbal Technology Co. , Ltd. ,in Shiji Town, Nanqiao Country, Anhui Province. Samples were collected from treatments under chrysanthemum-wheat rotation system receiving bio-organic manure application of 200 kg/667 m2, conventional chrysanthemum-wheat rotation system and chrysanthemum continuous cropping system. Chrysanthemum-wheat rotation system and biological manure obviously influenced the quality and yield of Chrysanthemum morifolium and continuous cropping soil enzyme activities. Compared with chrysanthemum continuous cropping system, total flavonoids, chlorogenic acid, soluble sugar and free amino acid contents, quantitative of ray floret, inflorescence diameter, diameter of tubular floret, number of branch, number of flower and yield of Chrysanthemum morifolium and the activities of urease, acid phosphatase, invertase and protease in soil were increased to 42.59 mg/g, 2.52 mg/g, 4.04 mg/g, 73.33 mg/100 g, 179.56, 5.57 cm, 1.43 cm, 36.10, 330.00 and 400.09 kg/667 m2, respectively, while hydrogen peroxidase of soil under chrysanthemum-wheat rotation system was decreased. Bio-organic manure application of 200 kg/667 m2 is benefit to soil environment establishment of chrysanthemum-wheat rotation system and enhancement of quality and yield of Chrysanthemum morifolium while reducing the obstacles of continuous cropping.

  7. Crop Rotational Effects on Yield Formation in Current Sugar Beet Production – Results From a Farm Survey and Field Trials

    Directory of Open Access Journals (Sweden)

    Heinz-Josef Koch

    2018-03-01

    Full Text Available In Europe, the framework for sugar beet (Beta vulgaris L. production was subject to considerable changes and for the future it is expected that sugar beet cultivation might concentrate around the sugar factories for economic reasons. Based on data from a national sugar beet farmers’ survey and multi-year crop rotation trials, the effects of cropping interval (number of years in between two subsequent sugar beet crops and of preceding crops on sugar yield were elucidated under current Central European management conditions. The dominating sugar beet cropping interval was ≥4 years in the farm survey with pronounced differences between regions. However, the cropping intervals 2, 3, and ≥4 years did not affect the sugar yield. Therefore, significant differences in sugar yield between regions were assumed to be caused by multiple interactions between year, site, and farmers’ skills. Throughout Germany, the dominating preceding crops in sugar beet cultivation were winter wheat (Triticum aestivum L. and winter barley (Hordeum vulgare L.. In the field trials, the sugar yield was 5% higher after pea (Pisum sativum L. compared to maize (Zea mays L. as preceding crop, while differences between the preceding crops pea and winter wheat, and wheat and maize were not significant. Repeated measurements of canopy development and leaf color during the growing season revealed a higher N-availability after pea as preceding crop. However, decreased growth after maize was not completely compensated for by high N-fertilizer doses. Overall, the causes for the differences in sugar yield between the preceding crops remained open. The results do not support concerns about substantial yield losses in sugar beet production due to a reduction in the cropping interval from 3 to 2 years. Nevertheless, short rotations with maize and sugar beet might increase the risk of Rhizoctonia solani crown and root rot infestation. Leguminous crops such as pea offer the potential

  8. Crop Rotational Effects on Yield Formation in Current Sugar Beet Production – Results From a Farm Survey and Field Trials

    Science.gov (United States)

    Koch, Heinz-Josef; Trimpler, Kerrin; Jacobs, Anna; Stockfisch, Nicol

    2018-01-01

    In Europe, the framework for sugar beet (Beta vulgaris L.) production was subject to considerable changes and for the future it is expected that sugar beet cultivation might concentrate around the sugar factories for economic reasons. Based on data from a national sugar beet farmers’ survey and multi-year crop rotation trials, the effects of cropping interval (number of years in between two subsequent sugar beet crops) and of preceding crops on sugar yield were elucidated under current Central European management conditions. The dominating sugar beet cropping interval was ≥4 years in the farm survey with pronounced differences between regions. However, the cropping intervals 2, 3, and ≥4 years did not affect the sugar yield. Therefore, significant differences in sugar yield between regions were assumed to be caused by multiple interactions between year, site, and farmers’ skills. Throughout Germany, the dominating preceding crops in sugar beet cultivation were winter wheat (Triticum aestivum L.) and winter barley (Hordeum vulgare L.). In the field trials, the sugar yield was 5% higher after pea (Pisum sativum L.) compared to maize (Zea mays L.) as preceding crop, while differences between the preceding crops pea and winter wheat, and wheat and maize were not significant. Repeated measurements of canopy development and leaf color during the growing season revealed a higher N-availability after pea as preceding crop. However, decreased growth after maize was not completely compensated for by high N-fertilizer doses. Overall, the causes for the differences in sugar yield between the preceding crops remained open. The results do not support concerns about substantial yield losses in sugar beet production due to a reduction in the cropping interval from 3 to 2 years. Nevertheless, short rotations with maize and sugar beet might increase the risk of Rhizoctonia solani crown and root rot infestation. Leguminous crops such as pea offer the potential for higher

  9. 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.

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

    Science.gov (United States)

    Saljnikov, E.

    2009-04-01

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

  11. The Effects of Cattle Manure and Garlic Rotation on Soil under Continuous Cropping of Watermelon (Citrullus lanatus L.)

    Science.gov (United States)

    Liu, Changming; Wang, Yongqi; Ma, Jianxiang; Zhang, Yong; Li, Hao; Zhang, Xian

    2016-01-01

    Continuous cropping of watermelon (Citrullus lanatus L.) can lead to reduced yield and quality. We aimed to determine the effects of cattle manure addition and rotation with green garlic to improve yield and reduce disease incidence in watermelon and to examine the effects on the biological and chemical characteristics of the soil. Field experiments were performed during 2012–2014 on land previously under two years of continuous watermelon cropping in northwest China. We examined three treatment combinations: watermelon and garlic rotation, cattle manure application before watermelon planting, and combined cattle manure addition and crop rotation. Watermelon monoculture was retained as a control. Watermelon yield was significantly higher and disease incidence was lower in the treatments than the control. The populations of soil bacteria and actinomycetes and the bacteria/fungi ratio increased significantly and soil enzyme activities were generally enhanced under treatments. Available nutrients and soil organic matter contents were much higher under experimental treatments than the control. Results suggest both cattle manure application and garlic rotation can ameliorate the negative effects of continuous cropping. The combined treatment of cattle manure addition and green garlic rotation was optimal to increase yield, reduce disease incidence and enhance soil quality. PMID:27258145

  12. The Effects of Cattle Manure and Garlic Rotation on Soil under Continuous Cropping of Watermelon (Citrullus lanatus L.).

    Science.gov (United States)

    Yang, Ruiping; Mo, Yanling; Liu, Changming; Wang, Yongqi; Ma, Jianxiang; Zhang, Yong; Li, Hao; Zhang, Xian

    2016-01-01

    Continuous cropping of watermelon (Citrullus lanatus L.) can lead to reduced yield and quality. We aimed to determine the effects of cattle manure addition and rotation with green garlic to improve yield and reduce disease incidence in watermelon and to examine the effects on the biological and chemical characteristics of the soil. Field experiments were performed during 2012-2014 on land previously under two years of continuous watermelon cropping in northwest China. We examined three treatment combinations: watermelon and garlic rotation, cattle manure application before watermelon planting, and combined cattle manure addition and crop rotation. Watermelon monoculture was retained as a control. Watermelon yield was significantly higher and disease incidence was lower in the treatments than the control. The populations of soil bacteria and actinomycetes and the bacteria/fungi ratio increased significantly and soil enzyme activities were generally enhanced under treatments. Available nutrients and soil organic matter contents were much higher under experimental treatments than the control. Results suggest both cattle manure application and garlic rotation can ameliorate the negative effects of continuous cropping. The combined treatment of cattle manure addition and green garlic rotation was optimal to increase yield, reduce disease incidence and enhance soil quality.

  13. The effect of location and facility demand on the marginal cost of delivered wood chips from energy crops: A case study of the state of Tennessee

    International Nuclear Information System (INIS)

    Graham, R.L.; Liu, W.; Downing, M.; Noon, C.; Daly, M.; Moore, A.

    1995-01-01

    Cost-supply curves for delivered wood chips from short rotation woody crops were calculated for 21 regularly-spaced locations spanning the state of Tennessee. These curves were used to systematically evaluate the combined effects of location and facility demand on wood chip feedstock costs in Tennessee. The cost-supply curves were developed using BRAVO, a GIS-based decision support system which calculates marginal cost of delivering wood chips to a specific location given road network maps and maps of farmgate prices and supplies of woody chips from short rotation energy crops. Marginal costs of delivered chips varied by both facility location in the state and facility demand. Marginal costs were lowest in central Tennessee unless the facility demand was greater than 2.7 million dry Mg per year (3 million dry tons per year) in which case west Tennessee was the lowest cost region. Marginal costs rose rapidly with increasing facility demand in the mountainous eastern portion of the state. Transportation costs accounted for 18 to 29% of the delivered cost and ranged between $8 and $18/dry Mg ($7 and $16/dry ton). Reducing the expected farmer participation rate from 100% to 50% or 25% dramatically raised the marginal costs of feedstock supply in the east and central regions of the state. The analysis demonstrates the need to use geographically-specific information when projecting the potential costs and supplies of biomass feedstock

  14. Effect of zone and crops rotation on Ischaemum rugosum and resistance to bispyribac-sodium in Ariari, Colombia

    OpenAIRE

    Plaza, G.; Hernández, F.A.

    2014-01-01

    The objectives of this research were to evaluate (1) weed species presented in rice fields in relation to the geographical zone and crop rotation and (2) the resistance level of Ischaemum rugosum to the herbicide bispyribac-sodium. For the first objective, were sampled 79 commercial fields of rice to establish weed density, coverage, and rotation system in the evaluated fields with record of bispyribac-sodium application of at least five years. To reach the second objective, the seeds were co...

  15. Water Quality Changes in a Short-Rotation Woody Crop Riparian Buffer

    Science.gov (United States)

    Rosa, D.; Clausen, J.; Kuzovkina, J.

    2016-12-01

    Converting riparian buffers in agricultural areas from annual row crops to short rotation woody crops (SRWCs) grown for biofuel can provide both water quality benefits and a financial incentive for buffer adoption among agricultural producers. A randomized complete block design was used to determine water quality changes resulting from converting plots previously cultivated in corn to SRWC willow (Salix. spp) adjacent to a stream in Storrs, CT. Both overland flow and ground water samples were analyzed for total nitrogen (TN), nitrate + nitrite (NO2+NO3-N), and total phosphorus (TP). Overland flow was also analyzed for suspended solids concentration (SSC). Lower (p = 0.05) concentrations of TN (56%) and TP (61%) were observed in post-coppice surface runoff from willow plots than from corn plots. Shallow ground water concentrations at the edge of willow plots were lower in TN (56%) and NO3+NO2-N (64%), but 35% higher in TP, than at the edge of corn plots. SSC was also lower (72%) in overland flow associated with willow compared to corn. The treatment had no effect on discharge or mass export. These results suggest conversion from corn to a SRWC in a riparian area can provide water quality benefits similar to those observed in restored and established buffers.

  16. Modeling poplar growth as a short rotation woody crop for biofuels in the Pacific Northwest

    International Nuclear Information System (INIS)

    Hart, Q.J.; Tittmann, P.W.; Bandaru, V.; Jenkins, B.M.

    2015-01-01

    Predicting the economic viability and environmental sustainability of a biofuels industry based on intensively cultivated short rotation woody crops (SRWC) requires spatial predictions of growth and yield under various environmental conditions and across large regions. The Physiological Principles in Predicting Growth (3PG) model was modified to evaluate the growth and yield of coppiced poplar (Populus spp). This included an additional biomass partitioning method and developing a sub-model which takes into account the impact of coppicing on post harvest regeneration, extending the applicability of the 3PG model to coppice management regimes. The parameterized model was applied to the entire Pacific Northwest of the United States, using appropriate climate and soil input data. Results predict the yield of poplar cultivation at a spatial resolution of ≈64 km 2 throughout the ≈8,000,000 km 2 of the study region. Existing agricultural cultivation patterns were used to estimate regional water availability for irrigation, and for non-irrigated regions, land cover features including ownership, slope, soil salinity and water table depth where used to select areas with a real potential to support a SRWC plantation. Results can be integrated with other models that allow for optimizing crop selection and biorefinery site selection. Important results include; an updated 3PG model for coppiced SRWC plantings, estimates of biomass feedstock yields under different irrigation patterns and weather conditions, and estimates for feedstock availability when combined with crop adoption scenarios. - Highlights: • A poplar growth model was applied to the Pacific Northwest of the US. • We included a coppicing module to the exsiting 3PG growth model. • We investigated growth under irrigated and non-irrigated conditions. • We developed Geospatial yield estimates. • We discuss changes in yield from climate change

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

    Directory of Open Access Journals (Sweden)

    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

  18. 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...

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

    Directory of Open Access Journals (Sweden)

    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

  20. Measuring and partitioning soil respiration in sharkey shrink-swell clays under plantation grown short-rotation woody crops

    Science.gov (United States)

    Wilson G. Hood; Michael C. Tyree; Dylan N. Dillaway Dillaway; Theodor D. Leininger

    2015-01-01

    The Lower Mississippi Alluvial Valley (LMAV) offers an ecological niche for short-rotation woody crop (SRWC) production by mating marginal agricultural land with optimal growing conditions. Approximately 1.7 million ha within the LMAV consist of Sharkey shrink-swell clays. They are considered marginal in terms of traditional agricultural productivity due to their...

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

    Science.gov (United States)

    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.

  2. 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...

  3. [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 (available nutrient increased. The amounts of soil bacteria in C-R and B-R patterns, fungi in B-R rotation pattern, cellulose bacteria in R-R, C-R and B-R patterns and N-fixing bacteria in B-R pattern were improved by 285.7%-403.0%, 221.7%, 64.6-92.2% and 162.2%, respectively. Moreover, the differences in all microorganisms were significant. Thus, based on the experimental results of cold-waterlogged paddy field, it was concluded that changing from single cropping rice system to C-R, R-R and B-R rotation patterns had good effect in terms of improving total yield and economic benefits, and soil

  4. 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

    with and without catch crops, with field operation dates adapted to baseline and future climate change. Model projections showed an increase in the productivity and N leaching in the future that would be dependent on crop rotation and crop management, highlighting the importance of considering the whole rotation...... efficient strategies are required in the future. The uncertainty of climate change scenarios was assessed by using two different climate projections for predicting crop productivity and N leaching in Danish crop rotations, and this showed the consistency of the projected trends when used with the same crop......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...

  5. Simulated effects of crop rotations and residue management on wind erosion in Wuchuan, west-central Inner Mongolia, China.

    Science.gov (United States)

    Wang, Erda; Harman, Wyatte L; Williams, Jimmy R; Xu, Cheng

    2002-01-01

    For decades, wind erosion has triggered dust and sand storms, buffeting Beijing and areas of northwestern China to the point of being hazardous to human health while rapidly eroding crop and livestock productivity. The EPIC (Environmental Policy Integrated Climate) field-scale simulation model was used to assess long-term effects of improved crop rotations and crop residue management practices on wind erosion in Wuchuan County in Inner Mongolia. Simulation results indicate that preserving crop stalks until land is prepared by zone tillage for the next year's crop in lieu of using them as a source of heating fuel or livestock fodder significantly reduces wind erosion by 60%. At the same time, grain and potato (Solanum tuberosum L.) yields were maintained or improved. Significant reductions in erosion, 35 to 46%, also resulted from delaying stalk removal until late January through late April. Yearly wind erosion was concentrated in April and May, the windiest months. Additionally, the use of alternative crop rotations resulted in differences in wind erosion, largely due to a difference in residue stature and quality and differences in biomass produced. As a result, altering current crop rotation systems by expanding corn (Zea mays L.), wheat (Triticum aestivum L.), and millet [Sorghum bicolor (L.) Moench] and reducing potato and pea (Pisum sativum L.) production significantly reduced simulated wind erosion, thus diminishing the severity of dust and sand storms in northwestern China. Saving and protecting topsoil over time will sustain land productivity and have long-term implications for improving conditions of rural poverty in the region.

  6. [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.

  7. 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.

    Science.gov (United States)

    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

  8. MR assessment of the repaired rotator cuff: prevalence, size, location, and clinical relevance of tendon rerupture

    Energy Technology Data Exchange (ETDEWEB)

    Mellado, J.M. [Hospital Reina Sofia de Tudela, Servicio de Radiodiagnostico, Tudela, Navarra (Spain); Calmet, J.; Ballabriga, J.; Gine, J. [Hospital Universitari de Tarragona Joan XXIII, Servei de Cirurgia Ortopedica i Traumatologia, Tarragona (Spain); Olona, M. [Hospital Universitari de Tarragona Joan XXIII, Servei de Medicina Preventiva i Epidemiologia, Tarragona (Spain); Camins, A. [Hospital Universitari de Tarragona Joan XXIII, Institut de Diagnostic per la Imatge, Tarragona (Spain); Perez del Palomar, L. [Hospital Ernest Lluch, Servicio de Radiologia, Calatayud, Zaragoza (Spain)

    2006-10-15

    The objectives of this study were to use magnetic resonance (MR) imaging to evaluate the prevalence, size, location, and clinical relevance of tendon rerupture following complete repair of full-thickness rotator cuff tear (RCT). A total of 78 surgically proven full-thickness rotator cuff tears in 74 patients were retrospectively included in the study. Clinical assessment was performed using the University of California at Los Angeles score. Postoperative MR imaging was evaluated to determine prevalence, size, and location of tendon rerupture. At a mean 48.4 months' follow-up, 62 shoulders (79.5%) had favorable outcomes and 45 shoulders (57.6%) showed rerupture on MR imaging studies. Reruptures were significantly more prevalent among patients with intermediate-to-bad outcomes (81.3%), with surgically demonstrated two-tendon tears (78.9%) or three-tendon tears (100%), and with preoperative fatty degeneration of the supraspinatus muscle greater than 1 (91.6%). Reruptures were also significantly larger in those subgroups. Complete repair of RCT of all sizes may have favorable outcomes in a significant proportion of patients in spite of a high prevalence of reruptures. Preoperative tear size and degree of muscle fatty degeneration influence the prevalence and rerupture size. After repair of supraspinatus tears, reruptures tend to invade the posterior aspect of the tendon. (orig.)

  9. MR assessment of the repaired rotator cuff: prevalence, size, location, and clinical relevance of tendon rerupture

    International Nuclear Information System (INIS)

    Mellado, J.M.; Calmet, J.; Ballabriga, J.; Gine, J.; Olona, M.; Camins, A.; Perez del Palomar, L.

    2006-01-01

    The objectives of this study were to use magnetic resonance (MR) imaging to evaluate the prevalence, size, location, and clinical relevance of tendon rerupture following complete repair of full-thickness rotator cuff tear (RCT). A total of 78 surgically proven full-thickness rotator cuff tears in 74 patients were retrospectively included in the study. Clinical assessment was performed using the University of California at Los Angeles score. Postoperative MR imaging was evaluated to determine prevalence, size, and location of tendon rerupture. At a mean 48.4 months' follow-up, 62 shoulders (79.5%) had favorable outcomes and 45 shoulders (57.6%) showed rerupture on MR imaging studies. Reruptures were significantly more prevalent among patients with intermediate-to-bad outcomes (81.3%), with surgically demonstrated two-tendon tears (78.9%) or three-tendon tears (100%), and with preoperative fatty degeneration of the supraspinatus muscle greater than 1 (91.6%). Reruptures were also significantly larger in those subgroups. Complete repair of RCT of all sizes may have favorable outcomes in a significant proportion of patients in spite of a high prevalence of reruptures. Preoperative tear size and degree of muscle fatty degeneration influence the prevalence and rerupture size. After repair of supraspinatus tears, reruptures tend to invade the posterior aspect of the tendon. (orig.)

  10. Stem Weight Ratios of Siberian Elm (Ulmus Pumila L.) Grown as a Short Rotation Crop

    Energy Technology Data Exchange (ETDEWEB)

    Iriarte, Leyre; Fernandez, Jesus [Univ. Politecnica de Madrid (Spain). Dept. de Produccion Vegetal

    2006-07-15

    Siberian elm (Ulmus pumila L.) is a fast growing tree which has not been studied extensively for short rotation crop (SRC) purposes. Seedlings were planted in Madrid (Spain) in the year 2000 at a density of 1 plant/m{sup 2}. Trials were carried out in order to evaluate the biomass production in high-density plantations. The plantation was cut after the fourth growing season and evaluated for height, diameter, and dry weight. The same measurements were repeated for the sprouts of the 1st and 2nd year that followed. The mean biomass yield after 4 years was 101.6 g dw/m{sup 2} year-1; 269 g dw /m{sup 2} for 1-year-old sprouts and 480.4 g dw /m{sup 2} for 2-year-old sprouts. Correlations between height and basal diameter with dry weight were calculated for each year. There was a close correlation between the 4th year original plant weight and the 1-year-old sprouts but less than with the 2nd year. Water efficiency for biomass production was higher during the 2nd sprouting cycle.

  11. 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.

  12. Cover crop rotations in no-till system: short-term CO2 emissions and soybean yield

    Directory of Open Access Journals (Sweden)

    João Paulo Gonsiorkiewicz Rigon

    Full Text Available ABSTRACT: In addition to improving sustainability in cropping systems, the use of a spring and winter crop rotation system may be a viable option for mitigating soil CO2 emissions (ECO2. This study aimed to determine short-term ECO2 as affected by crop rotations and soil management over one soybean cycle in two no-till experiments, and to assess the soybean yields with the lowest ECO2. Two experiments were carried out in fall-winter as follows: i triticale and sunflower were grown in Typic Rhodudalf (TR, and ii ruzigrass, grain sorghum, and ruzigrass + grain sorghum were grown in Rhodic Hapludox (RH. In the spring, pearl millet, sunn hemp, and forage sorghum were grown in both experiments. In addition, in TR a fallow treatment was also applied in the spring. Soybean was grown every year in the summer, and ECO2 were recorded during the growing period. The average ECO2 was 0.58 and 0.84 g m2 h–1 with accumulated ECO2 of 5,268 and 7,813 kg ha–1 C-CO2 in TR and RH, respectively. Sunn hemp, when compared to pearl millet, resulted in lower ECO2 by up to 12 % and an increase in soybean yield of 9% in TR. In RH, under the winter crop Ruzigrazz+Sorghum, ECO2 were lower by 17%, although with the same soybean yield. Soil moisture and N content of crop residues are the main drivers of ECO2 and soil clay content seems to play an important role in ECO2 that is worthy of further studies. In conclusion, sunn hemp in crop rotation may be utilized to mitigate ECO2 and improve soybean yield.

  13. High yielding tropical energy crops for bioenergy production: Effects of plant components, harvest years and locations on biomass composition.

    Science.gov (United States)

    Surendra, K C; Ogoshi, Richard; Zaleski, Halina M; Hashimoto, Andrew G; Khanal, Samir Kumar

    2018-03-01

    The composition of lignocellulosic feedstock, which depends on crop type, crop management, locations and plant parts, significantly affects the conversion efficiency of biomass into biofuels and biobased products. Thus, this study examined the composition of different parts of two high yielding tropical energy crops, Energycane and Napier grass, collected across three locations and years. Significantly higher fiber content was found in the leaves of Energycane than stems, while fiber content was significantly higher in the stems than the leaves of Napier grass. Similarly, fiber content was higher in Napier grass than Energycane. Due to significant differences in biomass composition between the plant parts within a crop type, neither biological conversion, including anaerobic digestion, nor thermochemical pretreatment alone is likely to efficiently convert biomass components into biofuels and biobased products. However, combination of anaerobic digestion with thermochemical conversion technologies could efficiently utilize biomass components in generating biofuels and biobased products. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    Neel H.

    2006-01-01

    Full Text Available 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 fertilisers were applied in various plots led in randomised complete blocs with three replicates. Crop yield data were each season recorded over a 9-year period. Results showed that there was very low or no harvest in plots without fertilisers. Where fertilisers were applied, the yield generally increased but remained relatively low: only few crops and varieties adapted to the Mata ecology such as potatoes and fi nger millet responded well to fertilisers. Liming was absolutely necessary to get any acceptable crop yield improvement with NPK. High rate of rich farmyard manure was effi cient alone and its effect was seen up to 4 seasons after its four regular seasonal applications. Mata compost (C/N>25, 0,3 g P.kg-1 had little benefi cial effect. One, four and half, and eight tons of lime per ha applied 3 times in 8 years increased soil pH (in water but not up to 6,5. It is then concluded that to succeed improving food production at the CZN area, selection of crops and varieties to fi t ecological conditions and amending soils to fi t crops be combined, but not opposed.

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

    Science.gov (United States)

    Tahir, Muhammad; Mirza, M. Sajjad; Hameed, Sohail; Dimitrov, Mauricio R.; Smidt, Hauke

    2015-01-01

    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-1and 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 isolates with plant

  16. 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

  17. The potential for short-rotation woody crops to reduce US CO2 emissions

    International Nuclear Information System (INIS)

    Graham, R.L.; Wright, L.L.; Turhollow, A.F.

    1992-01-01

    Short-rotation woody crops (SRWC) could potentially displace fossil fuels and thus mitigate CO 2 buildup in the atmosphere. To determine how much fossil fuel SRWC might displace in the United States and what the associated fossil carbon savings might be, a series of assumptions must be made. These assumptions concern the net SRWC biomass yields per hectare (after losses); the amount of suitable land dedicated to SRWC production; wood conversion efficiencies to electricity or liquid fuels; the energy substitution properties of various fuels; and the amount of fossil fuel used in growing, harvesting, transporting, and converting SRWC biomass. Assuming the current climate, present production, and conversion technologies and considering a conservative estimate of the US land base available for SRWC (14 x 10 6 ha), it is calculated that SRWC energy could displace 33.2 to 73.1 x 10 6 Mg of fossil carbon releases, 3-6% of the current annual US emissions. The carbon mitigation potential per unit of land is larger with the substitution of SRWC for coal-based electricity production than for the substitution of SRWC-derived ethanol for gasoline. Assuming current climate, predicted conversion technology advancements, an optimistic estimate of the US land base available for SRWC (28 x 10 6 ha), and an optimistic average estimate of net SRWC yields (22.4 dry Mg/ha), it is calculate that SRWC energy could displace 148 to 242 x 10 6 Mg of annual fossil fuel carbon releases. Under this scenario, the carbon migration potential of SRWC-based electricity production would be equivalent to about 4.4% of current global fossil fuel emissions and 20% of current US fossil fuel emissions. 21 refs., 5 tabs

  18. Growth and yield of cowpea/sunflower crop rotation under different irrigation management strategies with saline water

    Directory of Open Access Journals (Sweden)

    Antônia Leila Rocha Neves

    2015-05-01

    Full Text Available This study aimed to evaluate the effect of management strategies of irrigation with saline water on growth and yield of cowpea and sunflower in a crop rotation. The experiment was conducted in randomized blocks with thirteen treatments and five replications. The treatments consisted of: T1 (control, T2, T3 and T4 using water of 0.5 (A1, 2.2 (A2, 3.6 (A3 and 5.0 (A4 dS m-1, respectively, during the entire crop cycle; T5, T6 and T7, use of A2, A3 and A4 water, respectively, only in the flowering and fructification stage of the crop cycle; using different water in a cyclic way, six irrigations with A1 followed by six irrigations with A2 (T8, A3 (T9 and A4, (T10, respectively; T11, T12 and T13, using water A2, A3 and A4, respectively, starting at 11 days after planting (DAP and continuing until the end of the crop cycle. These treatments were employed in the first crop (cowpea, during the dry season, and the same plots were used for the cultivation of sunflower as succeeding crop during rainy season. The strategies of use of saline water in the salt tolerant growth stage (treatments T5, T6 and T7 or cyclically (treatments T8, T9 and T10 reduced the amount of good quality water used in the production of cowpea by 34 and 47%, respectively, without negative impacts on crop yield, and did not show the residual effects of salinity on sunflower as a succeeding crop. Thus, these strategies appear promising to be employed in areas with water salinity problems in the semiarid region of Brazil.

  19. Location of Rotator Cuff Tear Initiation: A Magnetic Resonance Imaging Study of 191 Shoulders.

    Science.gov (United States)

    Jeong, Jeung Yeol; Min, Seul Ki; Park, Keun Min; Park, Yong Bok; Han, Kwang Joon; Yoo, Jae Chul

    2018-03-01

    Degenerative rotator cuff tears (RCTs) are generally thought to originate at the anterior margin of the supraspinatus tendon. However, a recent ultrasonography study suggested that they might originate more posteriorly than originally thought, perhaps even from the isolated infraspinatus (ISP) tendon, and propagate toward the anterior supraspinatus. Hypothesis/Purpose: It was hypothesized that this finding could be reproduced with magnetic resonance imaging (MRI). The purpose was to determine the most common location of degenerative RCTs by using 3-dimensional multiplanar MRI reconstruction. It was assumed that the location of the partial-thickness tears would identify the area of the initiation of full-thickness tears. Cross-sectional study; Level of evidence, 3. A retrospective analysis was conducted including 245 patients who had RCTs (nearly full- or partial-thickness tears) at the outpatient department between January 2011 and December 2013. RCTs were measured on 3-dimensional multiplanar reconstruction MRI with OsiriX software. The width and distance from the biceps tendon to the anterior margin of the tear were measured on T2-weighted sagittal images. In a spreadsheet, columns of consecutive numbers represented the size of each tear (anteroposterior width) and their locations with respect to the biceps brachii tendon. Data were pooled to graphically represent the width and location of all tears. Frequency histograms of the columns were made to visualize the distribution of tears. The tears were divided into 2 groups based on width (group A, location related to size. The mean width of all RCTs was 11.9 ± 4.1 mm, and the mean length was 11.1 ± 5.0 mm. Histograms showed the most common location of origin to be 9 to 10 mm posterior to the biceps tendon. The histograms of groups A and B showed similar tear location distributions, indicating that the region approximately 10 mm posterior to the biceps tendon is the most common site of tear initiation. These

  20. 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.

  1. 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

  2. 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

  3. 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...

  4. 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.

  5. 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

  6. Cereal yield and quality as affected by N availability in organic and conventional crop rotations in Denmark

    DEFF Research Database (Denmark)

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

    2011-01-01

    barley–(faba bean or grass-clover)–potato–winter wheat. Experiments were done at three locations representative of the different soil types and climatic conditions in Denmark. The three organic systems that included faba bean as the N fixing crop comprised a system with manure (stored pig slurry...... systems. Scenario analyses conducted with the FASSET model indicated the possibility of increasing N fertilization without significantly affecting N leaching if there is an adequate catch crop management. This would also improve yields of cereal production of organic farming in Denmark...

  7. Effects of Crop Rotation, N Management, Tillage, and Controlled Drainage on nitrate-N Loss in Drain Flow

    Science.gov (United States)

    Ma, L.; Malone, R.; Ahuja, L.; Kanwar, R. S.

    2007-12-01

    Accurate simulation of agricultural management effects on N loss in tile drainage is vitally important for understanding hypoxia in the Gulf of Mexico. An experimental study was initiated in 1978 at Nashua, Iowa of the USA to study long-term effects of tillage, crop rotation, and N management practices on subsurface drainage flow and associated N losses. The Root Zone Water Quality Model (RZWQM) was applied to evaluate management effects (tillage, crop rotation, N application, and controlled drainage) on N loss in drain flow. RZWQM simulated the observed increase in N concentration in drain flow with increasing tillage intensity from NT (no-till) to RT (ridge till) to CP (chisel plow) and to MP (moldboard plow). It also adequately simulated tillage effects on yearly drain flow and yearly N loss in drain flow. On the other hand, RZWQM adequately simulated lower yearly drain flow and lower flow-weighted N concentration in drain flow under CS (corn-soybean) and SC (soybean-corn) than under CC (continuous corn). The model also simulated higher N loss from fertilizer-N applications than from manure-N applications. Applying the newly suggested N management practice for the Midwest of controlled drainage, the model simulated a 30% reduction in drain flow and a 29% decrease in N losses in drain flow under controlled drainage (CD) compared to free drainage (FD). With most of the simulations in reasonably close agreement with observations, we concluded that RZWQM is a promising tool for quantifying the relative effects of tillage, crop rotation, N application, and controlled drainage on N loss in drainage flow. Further improvements on simulated management effects on N mineralization and plant N uptake are needed, however.

  8. Effects of rotation of cotton (Gossypium hirsutum L.) and soybean [Glycine max (L.) Merr.] crops on soil fertility in Elizabeth, Mississippi, USA

    OpenAIRE

    H.A., Reddy, K. and Pettigrew, W.T.

    2018-01-01

    The effects of cotton (Gossypium hirsutum L.): soybean [Glycine max (L.) Merr.] rotation on the soil fertility levels are limited. An irrigated soybean: cotton rotation experiment was conducted from 2012 through 2015 near Elizabeth, Mississippi, USA. The crop rotation sequences were included continuous cotton (CCCC), continuous soybean (SSSS), cotton-soybean-cotton-soybean (CSCS), cotton-soybean-soybean-cotton (CSSC), soybean-cotton-cotton-soybean (SCCS), soybean-cotton-soybean-cotton (SCSC)....

  9. On weed competition and population dynamics : considerations for crop rotations & organic farming

    NARCIS (Netherlands)

    Mertens, S.K.

    2002-01-01

    Key words: organic farming, weeds, weed management, weed ecology, weed diversity, matrix population model, elasticity analysis, neighbourhood model, survey, crop row spacing, mechanical hoe, harrow, Polygonum convolvulus ,

  10. Modeling impacts of water and fertilizer management on ecosystem services from rice rotated crop systems in China

    Science.gov (United States)

    Chen, Han; Yu, Chaoqing; Li, Changsheng; Huang, Xiao; Zhang, Jie; Yue, Yali; Huang, Guorui

    2015-04-01

    Sustainable intensification in agriculture has stressed the need for management practices that could increase crop yields while simultaneously reducing environmental impacts. It is well recognized that water and nutrient management hold great promise to address these goals. This study uses the DNDC biogeochemical model to stimulate the impacts of water regime and nitrogen fertilizer management interactions on ecosystem services of rice rotated crop systems in China. County-level optimal nitrogen fertilizer application rates under various water management practices were captured and then multiple scenarios of water and nitrogen fertilizer management were set to more than 1600 counties with rice rotations in China. Results indicate that an national average of 15.7±5.9% (the mean value and standard deviation derive from variability of three water management practices) reduction of nitrogen fertilizer inputs can be achieved without significantly sacrificing rice yields. On a national scale, shallow flooding with optimal N application rates appear most potential to enhance ecosystem services, which led to 10.6% reduction of nitrogen fertilizer inputs, 34.3% decrease of total GHG emissions, 2.8% less of overall N loss (NH3 volatilization, denitrification and N leaching) and a 1.7% increase of rice yields compared to the baseline scenario. Regional GHG emissions mitigation derived from water regime change vary with soil properties and the multiple crop index. Among the main production regions of rice in China, the highest reduction happened in Jiangxu, Yunnan, Guizhou and Hubei (more than 40% reduction) with high SOC, high multiple crop index and low clay fraction. The highest reduction of GHG emissions derived from reducing current N application rate to optimal rate appeared in Zhejiang, Guangdong, Jiangsu where the serious over-application of mineral N exit. It was concluded that process models like DNDC would act an essential tool to identify sustainable agricultural

  11. Microbial community responses to soil tillage and crop rotation in a corn/soybean agroecosystem.

    Science.gov (United States)

    Smith, Chris R; Blair, Peter L; Boyd, Charlie; Cody, Brianne; Hazel, Alexander; Hedrick, Ashley; Kathuria, Hitesh; Khurana, Parul; Kramer, Brent; Muterspaw, Kristin; Peck, Charles; Sells, Emily; Skinner, Jessica; Tegeler, Cara; Wolfe, Zoe

    2016-11-01

    The acreage planted in corn and soybean crops is vast, and these crops contribute substantially to the world economy. The agricultural practices employed for farming these crops have major effects on ecosystem health at a worldwide scale. The microbial communities living in agricultural soils significantly contribute to nutrient uptake and cycling and can have both positive and negative impacts on the crops growing with them. In this study, we examined the impact of the crop planted and soil tillage on nutrient levels, microbial communities, and the biochemical pathways present in the soil. We found that farming practice, that is conventional tillage versus no-till, had a much greater impact on nearly everything measured compared to the crop planted. No-till fields tended to have higher nutrient levels and distinct microbial communities. Moreover, no-till fields had more DNA sequences associated with key nitrogen cycle processes, suggesting that the microbial communities were more active in cycling nitrogen. Our results indicate that tilling of agricultural soil may magnify the degree of nutrient waste and runoff by altering nutrient cycles through changes to microbial communities. Currently, a minority of acreage is maintained without tillage despite clear benefits to soil nutrient levels, and a decrease in nutrient runoff-both of which have ecosystem-level effects and both direct and indirect effects on humans and other organisms.

  12. Determination of 3D location and rotation of lumbar vertebrae in CT images by symmetry-based auto-registration

    Science.gov (United States)

    Vrtovec, Tomaž; Likar, Boštjan; Pernuš, Franjo

    2007-03-01

    Quantitative measurement of vertebral rotation is important in surgical planning, analysis of surgical results, and monitoring of the progression of spinal deformities. However, many established and newly developed techniques for measuring axial vertebral rotation do not exploit three-dimensional (3D) information, which may result in virtual axial rotation because of the sagittal and coronal rotation of vertebrae. We propose a novel automatic approach to the measurement of the location and rotation of vertebrae in 3D without prior volume reformation, identification of appropriate cross-sections or aid by statistical models. The vertebra under investigation is encompassed by a mask in the form of an elliptical cylinder in 3D, defined by its center of rotation and the rotation angles. We exploit the natural symmetry of the vertebral body, vertebral column and vertebral canal by dividing the vertebral mask by its mid-axial, mid-sagittal and mid-coronal plane, so that the obtained volume pairs contain symmetrical parts of the observed anatomy. Mirror volume pairs are then simultaneously registered to each other by robust rigid auto-registration, using the weighted sum of absolute differences between the intensities of the corresponding volume pairs as the similarity measure. The method was evaluated on 50 lumbar vertebrae from normal and scoliotic computed tomography (CT) spinal scans, showing relatively large capture ranges and distinctive maxima at the correct locations and rotation angles. The proposed method may aid the measurement of the dimensions of vertebral pedicles, foraminae and canal, and may be a valuable tool for clinical evaluation of the spinal deformities in 3D.

  13. 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.

  14. 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.

  15. 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.

  16. Algal derivatives may protect crops from residual soil salinity: a case study on a tomato-wheat rotation

    Science.gov (United States)

    Di Stasio, Emilio; Raimondi, Giampaolo; Van Oosten, Michael; Maggio, Albino

    2017-04-01

    In coastal areas, summer crops are frequently irrigated with saline water. As a consequence, salts may accumulate in the root zone with detrimental effects on the following winter crops if the rainfall is insufficient to leach them. Two field experiments were performed in 2015-2016 on a field used for tomato (summer) wheat (winter) rotation cropping. The spring-summer experiment was carried in order to evaluate the effect of two algal derivatives (Ascophyllum nodosum), Rygex and Super Fifty, on a tomato crop exposed to increasing salinity and reduced nutrient availability. In the autumn-winter experiment we investigated the effect of residual salts from the previous summer irrigations on plant growth and yield of wheat treated with the same two algal extracts. The salt treatment for the irrigated summer crop was 80 mM NaCl plus a non-salinized control. The nutrient regimes were 100% and 50% of the tomato nutritional requirements. With both the seaweeds applications the salt stressed plants were demonstrated improved Relative Water Content and water potential. Nevertheless the total fresh biomass and the fruit fresh weight were enhanced only in the non salinized controls. Application of algal derivatives increased the total fresh weight over controls in the non salinized plants. The seaweed treatments enhanced the fruit fresh weight with an increase of 30% and 46% for Rygex and Super Fifty, respectively. Preliminary analysis of the ion profile in roots, shoots and leaves, indicates that the seaweed extracts may enhance the assimilation of ions in fruits affecting their nutritional value. The residual salinity of the summer experiment reduced the wheat biomass production. However, the seaweed extracts treatments improved growth under salinity. In the salt stressed plants the Super Fifty application increased shoots and ears by 34% and 23% respectively, compared to the non treated plants. Plant height was increased by application of seaweeds extracts for both the

  17. Crop rotation with no-till methods in cotton production of Uzbekistan

    OpenAIRE

    Khaitov, Botir; Allanov, Kholik

    2014-01-01

    Many soils of Uzbekistan have low water and nutrient holding capacity because of their sandy texture, low organic matter concentrations and degradation caused by long years of cotton monoculture. Conservation tillage production systems have the potential to increase the productivity of these soils by increasing soil humus and nitrogen content. As practiced conservation tillage helped to lessen N leaching losses, holding more of these elements within the topsoil as well as increase crop produc...

  18. 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 (carbohydrates contributions in every other fraction. GM/AX varied slightly between the soils. In conclusion, the crop rotation determined the accumulation of different levels of SOM in the two soils. The 18-months cultivation experiment determined an increase in the tillage intensity in ALF, and the introduction of N rich chickpea residues in CON. Consequently SOM chemical composition responded divergently in

  19. 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

  20. 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

  1. Agroforestry systems in northern Vietnam with Tephrosia candida as an alternative to short-fallow crop rotations

    Energy Technology Data Exchange (ETDEWEB)

    Hoang Fagerstroem, M.H. [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Soil Sciences

    2000-07-01

    Tephrosia candida was experimentally tested on-farm as an improved fallow species (TepFa), in hedgerows, (TepAl) and in a mulch transfer system (TepMu) in an upland rice (Oryza sativa) system on sloping land in northern Vietnam during the period 1996-1999. The objectives of this study were: (1) to investigate whether the existing monocropping (Mono) and short-fallow crop rotations (NaFa) are sustainable systems with respect to soil erosion and concomitant nutrient losses; (2) to determine whether agroforestry systems with Tephrosia (TepFa, TepAl, TepMu) can improve nutrient cycling and nutrient balances, for instance by preventing nutrient losses through erosion, as well as sustaining upland rice yields. A criteria system, including soil and nutrient losses, nutrient balances, changes of P-available pools, returns on labour and farmers' response, was used for comparing the systems tested. Only TepFa gave a positive input-output balance for both P and N. TepFa increased soil N and seemed to positively affect the release of soil labile P. However, the cost of Tephrosia seeds made the Net Present Value (NPV) of the Tephrosia fallow crop rotation system negative. TepMu increased upland rice yield by 50% compared to Mono. As a result, NPV was positive and sufficient rice for one more person could be produced per ha and year. However, the yield increase could cause a depletion of plant-available P, and the timing for pruning and mulching activities coincided with the farming activities in paddy fields. TepAl increased soil N, gave a neutral overall effect on crop yield but a negative NPV. NaFa gave a positive and highest NPV. In general, TepFa and TepMu were shown to increase crop yield per hectare with acceptable returns on labour and also to do better than Mono and NaFa with respect to preventing soil and nutrient losses through erosion. Recommendations are made for further research to focus on alternatives to maintain soil P, mechanisms of P pool reallocation and

  2. 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.

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

    Czech Academy of Sciences Publication Activity Database

    Yin, X.; Kersebaum, K. C.; Kollas, C.; Baby, S.; Beaudoin, N.; Manevski, K.; Palosuo, T.; Nendel, C.; Wu, L.; Hoffmann, M.; Hoffmann, H. D.; Sharif, B.; Armas-Herrera, C.; Bindi, M.; Charfeddine, M.; Conradt, T.; Constantin, J.; Ewert, F.; Ferrise, R.; Gaiser, T.; de Cortazar-Atauri, I. G.; Giglio, L.; Hlavinka, Petr; Lana, M.; Launay, M.; Louarn, G.; Manderscheid, R.; Mary, B.; Mirschel, W.; Moriondo, M.; Oeztuerk, M.; Pacholski, A.; Ripoche-Wachter, D.; Roetter, R. P.; Ruget, F.; Trnka, Miroslav; Ventrella, D.; Weigel, H-J.; Olesen, J. E.

    2017-01-01

    Roč. 84, mar (2017), s. 152-165 ISSN 1161-0301 R&D Projects: GA MŠk(CZ) LO1415 Institutional support: RVO:67179843 Keywords : air co2 enrichment * climate-change * catch crops * nitrogen-fertilization * wheat production * winter-wheat * model stics * sugar-beet * wide-range * growth * Continuous simulation * Grain N * Model calibration * Model ensemble * Model inter-comparison * Single year simulation Subject RIV: GC - Agronomy OBOR OECD: Agronomy, plant breeding and plant protection Impact factor: 3.757, year: 2016

  4. 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

  5. Changes in bird community composition in response to growth changes in short-rotation woody crop planting

    International Nuclear Information System (INIS)

    Tolbert, V.R.; Hanowski, J.; Schiller, A.; Hoffman, W.; Christian, D.; Lindberg, J.

    1997-01-01

    Hybrid poplar established as intensively managed short-rotation woody crops (SRWC) on former agricultural lands can provide habitat for wildlife. Studies of bird use of SRWC for nesting and during fall migration have shown that the numbers and kinds of breeding birds using mature plantings of hybrid poplar are similar to natural forested lands. In Minnesota, the number of species of breeding birds using habitat provided by clonal-trial plantings and young larger-scale plantings (12-64 ha) of hybrid poplar were initially most similar to those using grasslands and row-crops. As the plantings approached canopy closure, successional species became predominant. In the Pacific Northwest, breeding bird composition and density were very similar for mature plantings and forested areas; however, fall migrants were found primarily in forested areas. In the Southeast, preliminary comparisons of breeding bird use of plantings of sweetgum and sycamore with naturally regenerating forests of different ages and sizes and vegetation structure are showing no size effect on use. As with hybrid poplar, species use of the more mature plantings of sweetgum and sycamore was most similar to that of natural forests. (author)

  6. A rotating modulation imager for locating mid-range point sources

    International Nuclear Information System (INIS)

    Kowash, B.R.; Wehe, D.K.; Fessler, J.A.

    2009-01-01

    Rotating modulation collimators (RMC) are relatively simple indirect imaging devices that have proven useful in gamma ray astronomy (far field) and have more recently been studied for medical imaging (very near field). At the University of Michigan a RMC has been built to study the performance for homeland security applications. This research highlights the imaging performance of this system and focuses on three distinct regions in the RMC field of view that can impact the search for hidden sources. These regions are a blind zone around the axis of rotation, a two mask image zone that extends from the blind zone to the edge of the field of view, and a single mask image zone that occurs when sources fall outside the field of view of both masks. By considering the extent and impact of these zones, the size of the two mask region can be optimized for the best system performance.

  7. Energy and climate benefits of bioelectricity from low-input short rotation woody crops on agricultural land over a two-year rotation

    International Nuclear Information System (INIS)

    Njakou Djomo, S.; El Kasmioui, O.; De Groote, T.; Broeckx, L.S.; Verlinden, M.S.; Berhongaray, G.; Fichot, R.; Zona, D.; Dillen, S.Y.; King, J.S.; Janssens, I.A.; Ceulemans, R.

    2013-01-01

    Highlights: • A full energy and GHG balance of bioelectricity from SRWC was performed. • Bioelectricity was efficient; it reduced GHG by 52–54% relative to the EU non-renewable grid mix. • Bioelectricity required 1.1 m 2 of land kWh −1 ; land conversion released 2.8 ± 0.2 t CO 2e ha −1 . • SRWC reduced GHG emission when producing electricity during the 1st rotation period. - Abstract: Short-rotation woody crops (SRWCs) are a promising means to enhance the EU renewable energy sources while mitigating greenhouse gas (GHG) emissions. However, there are concerns that the GHG mitigation potential of bioelectricity may be nullified due to GHG emissions from direct land use changes (dLUCs). In order to evaluate quantitatively the GHG mitigation potential of bioelectricity from SRWC we managed an operational SRWC plantation (18.4 ha) for bioelectricity production on a former agricultural land without supplemental irrigation or fertilization. We traced back to the primary energy level all farm labor, materials, and fossil fuel inputs to the bioelectricity production. We also sampled soil carbon and monitored fluxes of GHGs between the SRWC plantation and the atmosphere. We found that bioelectricity from SRWCs was energy efficient and yielded 200–227% more energy than required to produce it over a two-year rotation. The associated land requirement was 0.9 m 2 kWh e -1 for the gasification and 1.1 m 2 kWh e -1 for the combustion technology. Converting agricultural land into the SRWC plantation released 2.8 ± 0.2 t CO 2e ha −1 , which represented ∼89% of the total GHG emissions (256–272 g CO 2e kWh e -1 ) of bioelectricity production. Despite its high share of the total GHG emissions, dLUC did not negate the GHG benefits of bioelectricity. Indeed, the GHG savings of bioelectricity relative to the EU non-renewable grid mix power ranged between 52% and 54%. SRWC on agricultural lands with low soil organic carbon stocks are encouraging prospects for

  8. Effects of crop rotation and management system on water-extractable organic matter concentration, structure, and bioavailability in a chernozemic agricultural soil.

    Science.gov (United States)

    Xu, Na; Wilson, Henry F; Saiers, James E; Entz, Martin

    2013-01-01

    Water-extractable organic matter (WEOM) in soil affects contaminant mobility and toxicity, heterotrophic production, and nutrient cycling in terrestrial and aquatic ecosystems. This study focuses on the influences of land use history and agricultural management practices on the water extractability of organic matter and nutrients from soils. Water-extractable organic matter was extracted from soils under different crop rotations (an annual rotation of wheat-pea/bean-wheat-flax or a perennial-based rotation of wheat-alfalfa-alfalfa-flax) and management systems (organic or conventional) and examined for its concentration, composition, and biodegradability. The results show that crop rotations including perennial legumes increased the concentration of water-extractable organic carbon (WEOC) and water-extractable organic nitrogen (WEON) and the biodegradability of WEOC in soil but depleted the quantity of water-extractable organic phosphorus (WEOP) and water-extractable reactive phosphorus. The 30-d incubation experiments showed that bioavailable WEOC varied from 12.5% in annual systems to 22% for perennial systems. The value of bioavailable WEOC was found to positively correlate with WEON concentrations and to negatively correlate with C:N ratio and the specific ultraviolet absorbance of WEOM. No significant treatment effect was present with the conventional and organic management practices, which suggested that WEOM, as the relatively labile pool in soil organic matter, is more responsive to the change in crop rotation than to mineral fertilizer application. Our results indicated that agricultural landscapes with contrasting crop rotations are likely to differentially affect rates of microbial cycling of organic matter leached to soil waters. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  9. 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

  10. 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.

  11. Sub-soil microbial activity under rotational cotton crops in Australia

    Science.gov (United States)

    Polain, Katherine; Knox, Oliver; Wilson, Brian; Pereg, Lily

    2016-04-01

    Soil microbial communities contribute significantly to soil organic matter formation, stabilisation and destabilisation, through nutrient cycling and biodegradation. The majority of soil microbial research examines the processes occurring in the top 0 cm to 30 cm of the soil, where organic nutrients are easily accessible. In soils such as Vertosols, the high clay content causes swelling and cracking. When soil cracking is coupled with rain or an irrigation event, a flush of organic nutrients can move down the soil profile, becoming available for subsoil microbial community use and potentially making a significant contribution to nutrient cycling and biodegradation in soils. At present, the mechanisms and rates of soil nutrient turnover (such as carbon and nitrogen) at depth under cotton rotations are mostly speculative and the process-response relationships remain unclear, although they are undoubtedly underpinned by microbial activity. Our research aims to determine the contribution and role of soil microbiota to the accumulation, cycling and mineralisation of carbon and nitrogen through the whole root profile under continuous cotton (Gossypium hirsutum) and cotton-maize rotations in regional New South Wales, Australia. Through seasonal work, we have established both baseline and potential microbial activity rates from 0 cm to 100 cm down the Vertosol profile, using respiration and colourimetric methods. Further whole soil profile analyses will include determination of microbial biomass and isotopic carbon signatures using phospholipid fatty acid (PLFA) methodology, identification of microbial communities (sequencing) and novel experiments to investigate potential rates of nitrogen mineralisation and quantification of associated genes. Our preliminary observations and the hypotheses tested in this three-year study will be presented.

  12. Location of Bioelectricity Plants in the Madrid Community Based on Triticale Crop: A Multicriteria Methodology

    Directory of Open Access Journals (Sweden)

    L. Romero

    2015-01-01

    Full Text Available This paper presents a work whose objective is, first, to quantify the potential of the triticale biomass existing in each of the agricultural regions in the Madrid Community through a crop simulation model based on regression techniques and multiple correlation. Second, a methodology for defining which area has the best conditions for the installation of electricity plants from biomass has been described and applied. The study used a methodology based on compromise programming in a discrete multicriteria decision method (MDM context. To make a ranking, the following criteria were taken into account: biomass potential, electric power infrastructure, road networks, protected spaces, and urban nuclei surfaces. The results indicate that, in the case of the Madrid Community, the Campiña region is the most suitable for setting up plants powered by biomass. A minimum of 17,339.9 tons of triticale will be needed to satisfy the requirements of a 2.2 MW power plant. The minimum range of action for obtaining the biomass necessary in Campiña region would be 6.6 km around the municipality of Algete, based on Geographic Information Systems. The total biomass which could be made available in considering this range in this region would be 18,430.68 t.

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

    Science.gov (United States)

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

    2009-01-01

    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...

  14. Crop Rotation Studies with Velvetbean (Mucuna deeringiana) for the Management of Meloidogyne spp.

    Science.gov (United States)

    Rodríguez-Kábana, R; Pinochet, J; Robertson, D G; Wells, L

    1992-12-01

    Results from a greenhouse experiment at Cabrils, Spain, with two velvetbean (Mucuna deeringiana) accessions (Florida and Mozambique) growing in sterilized sandy loam and inoculated with Meloidogyne arenaria race 2, M. incognita race 1, and M. javanica revealed that the legume was not a host for these nematodes. In contrast, roots of 'Clemson Spineless' okra (Hibiscus esculentum), 'Summer Crookneck' squash (Cucurbita pepo), and 'Davis' soybean (Glycine max) were galled by all three root-knot nematodes. Greenhouse experiments at Auburn, Alabama, using soils infested with Heterodera glycines (race 14) + M. incognita or with H. glycines + M. arenaria (race 2) showed that, in contrast to Davis soybean, a Mexican and the Florida velvetbean accessions were not hosts for the nematodes. An experiment with 'Florunner' peanut (Arachis hypogaea) and the Florida velvetbean in a field infested with M. arenaria (race 1), near Headland, Alabama, showed that significant juvenile populations of the nematode at peanut harvest time were present only in plots with peanut. A microplot rotation experiment demonstrated that 'Black Beauty' eggplant (Solanum melongena) following the Florida velvetbean had heavier shoots and lower numbers of M. arenaria juveniles in the roots and in the soil than eggplant after Summer Crookneck squash or Davis soybean.

  15. In Situ Groundwater Denitrification in the Riparian Zone of a Short-Rotation Woody Crop Experimental Watershed

    Science.gov (United States)

    Jeffers, J. B.; Jackson, C. R.; Rau, B.; Pringle, C. M.; Matteson, C.

    2017-12-01

    The southeastern United States has potential to become a major producer of short rotation woody crops (SRWC) for the production of biofuels, but this will require converting to more intensive forest management practices that will increase nitrate (NO3-) loading and alter nitrogen cycling in nearby freshwater ecosystems. Water quality monitoring in an experimental short-rotation woody crop watershed in the Coastal Plain of South Carolina has shown increased concentrations of NO3- in groundwater but no evidence of increased NO3- in riparian groundwater or surface waters. Forested riparian areas established as streamside management zones (SMZ) are known to act as buffers to surface water bodies by mitigating nutrients. The objectives of this study were to quantify denitrification by measuring dinitrogen (N2) and nitrous oxide (N2O) concentrations along groundwater flow paths and analyze relationships between denitrification estimates, nutrients, and water chemistry parameters. A network of piezometers has been established in the Fourmile Experimental Watershed at the Department of Energy - Savannah River Site. Water samples were collected monthly and were analyzed for concentrations of nutrients (temperature, specific conductivity, dissolved oxygen, pH, dissolved organic carbon) and dissolved gases (N2, Ar, N2O). Preliminary data showed greater dissolved N2O concentrations than dissolved N2 concentrations in groundwater. The ratios of N2O to combined end products of denitrification (N2O / N2O+N2) ranged from 0.33 to 0.99. Mean N2O+N2 concentrations were greater in groundwater samples in the SRWC plot and along the SMZ boundary than along the ephemeral stream within the riparian zone. Correlations between water chemistry parameters and N2 concentrations are indicative of known biogeochemical driving factors of denitrification. Continued monthly sampling will be coupled with analysis of nutrient concentrations (NO3-, NH4+, TN) to help determine transport and processing

  16. Do Cultivar, Geographical Location and Crop Season Influence Phenolic Profile of Walnut Leaves?

    Directory of Open Access Journals (Sweden)

    Rosa M. Seabra

    2008-06-01

    Full Text Available Walnut leaves from nine different cultivars (Arco, Franquette, Hartley, Lara, Marbot, Mayette, Meylannaise, Parisienne and Rego were studied for their phenolic compounds. Samples were harvested along three consecutive years, at two different geographical locations, in order to evaluate if significant differences in the phenolics composition can be related with genetic, climatic or geographical factors. Nine compounds (3-caffeoylquinic, 3-p-coumaroylquinic and 4-p-coumaroylquinic acids, quercetin 3- galactoside, quercetin 3-arabinoside, quercetin 3-xyloside, quercetin 3-rhamnoside, a quercetin 3-pentoside derivative and a kaempferol 3-pentoside derivative were quantified using an HPLC-DAD methodology. The qualitative profiles were identical for all samples, but differences were observed in terms of individual compounds’ contents. Multivariate statistical analysis was carried out, showing that significant differences exist among production years, which can be related to climatic reasons.

  17. Robust Optical Recognition of Cursive Pashto Script Using Scale, Rotation and Location Invariant Approach.

    Science.gov (United States)

    Ahmad, Riaz; Naz, Saeeda; Afzal, Muhammad Zeshan; Amin, Sayed Hassan; Breuel, Thomas

    2015-01-01

    The presence of a large number of unique shapes called ligatures in cursive languages, along with variations due to scaling, orientation and location provides one of the most challenging pattern recognition problems. Recognition of the large number of ligatures is often a complicated task in oriental languages such as Pashto, Urdu, Persian and Arabic. Research on cursive script recognition often ignores the fact that scaling, orientation, location and font variations are common in printed cursive text. Therefore, these variations are not included in image databases and in experimental evaluations. This research uncovers challenges faced by Arabic cursive script recognition in a holistic framework by considering Pashto as a test case, because Pashto language has larger alphabet set than Arabic, Persian and Urdu. A database containing 8000 images of 1000 unique ligatures having scaling, orientation and location variations is introduced. In this article, a feature space based on scale invariant feature transform (SIFT) along with a segmentation framework has been proposed for overcoming the above mentioned challenges. The experimental results show a significantly improved performance of proposed scheme over traditional feature extraction techniques such as principal component analysis (PCA).

  18. 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.

  19. 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. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Efect of organic barley-based crop rotations on soil nutrient balance in a semiarid environment for a 16-year experiment

    Science.gov (United States)

    Meco, Ramón; María Moreno, Marta; Lacasta, Carlos; Moreno, Carmen

    2013-04-01

    In natural ecosystems with no percolating moisture regime, the biogeochemical cycle can be considered a closed system because the nutrients extracted by the roots will be returned to the soil after a certain time. In organic farming, a cycle model as close as possible is taken as a guideline, but we have to consider that unlike natural ecosystems, where most of the nutrients remain in the cycle, the agrosystems are open cycles. To achieve a sustainable fertility of the soil, the soil nutrient levels, the extractions according to the expected crop yields and the export refunds in the form of crop residues, biological nitrogen fixation, green manure or compost will have to be determined. Nutrient balance should be closed with external inputs, always avoiding to be a source of negative impacts on the environment. In organic farming without exogenous inputs, the effect of the crop rotations is much more noticeable in the nutrient balance than in the conventional farming fields which every year receive inputs of nutrients (nitrogen, phosphorus and potassium) in the form of chemical fertilizers. The most extractive crop rotations are those that produce a greater decrease in soil reserves, and in these cases exogenous inputs to maintain sustainability should be considered; however, in less extractive crop rotations, extractions can be restored by the edaphogenesis processes. In this work, soil organic matter, phosphorus and potassium balances were analyzed in different organic barley-based crop rotations (barley monoculture [b-b] and in rotation with vetch for hay production [B-Vh], vetch as green manure [B-Vm], sunflower [B-S], chickpea [B-C] and fallow [B-F]) in clay soils under a semiarid environment ("La Higueruela" Experimental Farm, Santa Olalla, Toledo, central Spain) over a 16 year period. Additionally, barley monoculture in conventional farming [B-B] was included. In the organic system, the fertilization involved the barley straw in all rotations, the sunflower

  1. 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

  2. Effect of contrasting crop rotation systems on soil chemical and biochemical properties and plant root growth in organic farming: First results

    OpenAIRE

    Elga Monaci; Serena Polverigiani; Davide Neri; Michele Bianchelli; Rodolfo Santilocchi; Marco Toderi; Paride D'Ottavio; Costantino Vischetti

    2017-01-01

    Organic farming is claimed to improve soil fertility. Nonetheless, among organic practices, net C-inputs may largely vary in amount and composition and produce different soil conditions for microbial activity and plant-root system adaptation and development. In this study, we hypothesised that, in the regime of organic agriculture, soil chemical and biochemical properties can substantially differ under contrasting crop rotation systems and produce conditions of soil fertility to which the pla...

  3. Abandoned lands and tree crops on short rotations : a favourable combination for energy; Les terres abandonnees et les cultures d`arbres sur courtes rotations : une conjoncture favorable pour l`energie

    Energy Technology Data Exchange (ETDEWEB)

    Labrecque, M.; Teodorescu, T.I. [Jardin botanique de Montreal, Montreal, PQ (Canada)

    1998-05-01

    Short-rotation intensive culture on abandoned farmlands has successfully been used in Sweden to produce woody biomass as an energy source. Because of changing economic conditions, it is estimated that 33,000 hectares of farmland are abandoned every year in Quebec. Although it is impractical to use these lands for conventional farming crops, they are nevertheless well-suited for tree plantations. Results of a study to demonstrate the feasibility of this method in Quebec were discussed. Three plantations of one hectare each were established on abandoned farmlands 90 km southwest of Montreal for this pilot study. Salix discolor and Salix viminalis were planted in fertilized and non-fertilized plots. A detailed analysis of costs for planting, maintaining, and harvesting the crop was conducted over a period of three years. Results demonstrate that the economic and soil conditions in southern Quebec make wood biomass a profitable crop on abandoned farmlands. 6 refs., 2 tabs., 1 fig.

  4. 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 (pbalance but also with regard to soil fertility. New upland crop management practices where first implemented during land-preparation for dry season (July) 2015 where i) 6t/ha rice straw

  5. Gene Introgression in Weeds Depends on Initial Gene Location in the Crop:Brassica napus-Raphanus raphanistrumModel.

    Science.gov (United States)

    Adamczyk-Chauvat, Katarzyna; Delaunay, Sabrina; Vannier, Anne; François, Caroline; Thomas, Gwenaëlle; Eber, Frédérique; Lodé, Maryse; Gilet, Marie; Huteau, Virginie; Morice, Jérôme; Nègre, Sylvie; Falentin, Cyril; Coriton, Olivier; Darmency, Henri; Alrustom, Bachar; Jenczewski, Eric; Rousseau-Gueutin, Mathieu; Chèvre, Anne-Marie

    2017-07-01

    The effect of gene location within a crop genome on its transfer to a weed genome remains an open question for gene flow assessment. To elucidate this question, we analyzed advanced generations of intergeneric hybrids, derived from an initial pollination of known oilseed rape varieties ( Brassica napus , AACC, 2 n  = 38) by a local population of wild radish ( Raphanus raphanistrum , RrRr, 2 n  = 18). After five generations of recurrent pollination, 307 G5 plants with a chromosome number similar to wild radish were genotyped using 105 B. napus specific markers well distributed along the chromosomes. They revealed that 49.8% of G5 plants carried at least one B. napus genomic region. According to the frequency of B. napus markers (0-28%), four classes were defined: Class 1 (near zero frequency), with 75 markers covering ∼70% of oilseed rape genome; Class 2 (low frequency), with 20 markers located on 11 genomic regions; Class 3 (high frequency), with eight markers on three genomic regions; and Class 4 (higher frequency), with two adjacent markers detected on A10. Therefore, some regions of the oilseed rape genome are more prone than others to be introgressed into wild radish. Inheritance and growth of plant progeny revealed that genomic regions of oilseed rape could be stably introduced into wild radish and variably impact the plant fitness (plant height and seed number). Our results pinpoint that novel technologies enabling the targeted insertion of transgenes should select genomic regions that are less likely to be introgressed into the weed genome, thereby reducing gene flow. Copyright © 2017 by the Genetics Society of America.

  6. Cadmium contamination of soil and crops is affected by intercropping and rotation systems in the lower reaches of the Minjiang River in south-western China.

    Science.gov (United States)

    Liu, Yang; Liu, Kai; Li, Yong; Yang, Wanqin; Wu, Fuzhong; Zhu, Peng; Zhang, Jian; Chen, Lianghua; Gao, Shun; Zhang, Li

    2016-06-01

    Cadmium (Cd) accumulation and pollution in arable soils are particularly serious in the lower reaches of the Minjiang River in southwest of China. In this study, the remediation efficiency of Cd contamination in arable soils, the distribution pattern of Cd concentration in crops, and the food safety to humans of three typical cropping systems (S1: maize + sweet potato-Chinese cabbage, S2: maize + ginger-stem mustard, and S3: rice) were investigated and evaluated. After 1-year rotation, the percentage of Cd extracted by crops from the plough soil layer was observed in three system fields with the trend of S1 (2.30 %) > S2 (1.16 %) > S3 (0.21 %) and Cd extraction amount in crops was maximum in sweet potato, then in maize. The same kind of crop had the same pattern of Cd distribution in organs, and the edible parts generally accumulated less Cd amount than the inedible parts. Further, the grain crops were found to possibly be suitable one for using as phytoaccumulators of Cd contamination for farmlands. Direct consumption of these crops from the three systems would pose a high health risk to local inhabitants since it would result in the monthly intake of Cd (247 μg kg(-1) body weight) being nearly 10 times higher than the recommended tolerable monthly intake (RTMI) (25 μg kg(-1) body weight), resulting mainly from the consumption of vegetables rather than the grains, which would be potentially reduced by these foods being consumed by livestock firstly.

  7. 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. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. 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)

  9. 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

    Directory of Open Access Journals (Sweden)

    Chang-An Liu

    2016-06-01

    Full Text Available 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.

  10. Cover crop management influences residue biomass and subsequent weed suppression in a conservation agriculture corn and cotton rotation

    Science.gov (United States)

    Use of winter cover crops is an integral component of conservation systems in corn and cotton. However, data concerning cover management and subsequent residue and weed biomass is needed. Field experiments were conducted from autumn of 2003 through cash crop harvest in 2006 at the Alabama Agricultur...

  11. Long-term conventional and no-tillage effects on field hydrology and yields of a dryland crop rotation

    Science.gov (United States)

    Semiarid dryland crop yields with no-till, NT, residue management are often greater than stubble-mulch, SM, tillage as a result of improved soil conditions and water conservation, but information on long-term tillage effects on field hydrology and sustained crop production are needed. Our objective ...

  12. 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.

  13. Impacts of Rotation Schemes on Ground-Dwelling Beneficial Arthropods.

    Science.gov (United States)

    Dunbar, Mike W; Gassmann, Aaron J; O'Neal, Matthew E

    2016-10-01

    Crop rotation alters agroecosystem diversity temporally, and increasing the number of crops in rotation schemes can increase crop yields and reduce reliance on pesticides. We hypothesized that increasing the number of crops in annual rotation schemes would positively affect ground-dwelling beneficial arthropod communities. During 2012 and 2013, pitfall traps were used to measure activity-density and diversity of ground-dwelling communities within three previously established, long-term crop rotation studies located in Wisconsin and Illinois. Rotation schemes sampled included continuous corn, a 2-yr annual rotation of corn and soybean, and a 3-yr annual rotation of corn, soybean, and wheat. Insects captured were identified to family, and non-insect arthropods were identified to class, order, or family, depending upon the taxa. Beneficial arthropods captured included natural enemies, granivores, and detritivores. The beneficial community from continuous corn plots was significantly more diverse compared with the community in the 2-yr rotation, whereas the community in the 3-yr rotation did not differ from either rotation scheme. The activity-density of the total community and any individual taxa did not differ among rotation schemes in either corn or soybean. Crop species within all three rotation schemes were annual crops, and are associated with agricultural practices that make infield habitat subject to anthropogenic disturbances and temporally unstable. Habitat instability and disturbance can limit the effectiveness and retention of beneficial arthropods, including natural enemies, granivores, and detritivores. Increasing non-crop and perennial species within landscapes in conjunction with more diverse rotation schemes may increase the effect of biological control of pests by natural enemies. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  14. 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)

  15. Input-output cost of agronomic production of crops under rotate growing condition for applying to Mediterranean Italian buffaloes

    Directory of Open Access Journals (Sweden)

    N. Berardo

    2010-02-01

    Full Text Available Forage availability with low cost of production is the main farmer requisite for obtaining a competitive husbandry dairy product in the market. Cropping system for silage consumption differently impact the cost of Milk Feeding Unit (MFU and sustainable agronomic cultivation of herbage production. The experiment aimed to assess the analytical cost of MFU per hectare in four forage cropping system models based on two crops per year bred under irrigated and rainfed condition in a Mediterranean site with intensive buffaloes breeding pressure.

  16. Crop yield, weed infestation and soil fertility responses to contrasted ploughing intensity and manure additions in a Mediterranean organic crop rotation

    OpenAIRE

    Baldivieso-Freitas, P.; Blanco-Moreno, José Manuel; Armengot, Laura; Chamorro, Lourdes; Romanyà, Joan; Sans, F. Xavier

    2018-01-01

    Conservation agriculture and organic farming are two alternative strategies that aim to improve soil quality and fertility in arable cropping systems through the deployment of different practices, that are rarely combined. While conservation agriculture practices include reducing tillage intensity and maintaining soil cover all year round to prevent soil erosion, organic farming focuses on nutrient recycling, using farmyard manure and green manure to enhance soil quality. However, these pract...

  17. 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

    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...... 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...... 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...

  18. 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...

  19. The influence of nitrogen fertiliser rate and crop rotation on soil methane flux in rain-fed potato fields in Wuchuan County, China

    International Nuclear Information System (INIS)

    Wang, Liwei; Pan, Zhihua; Xu, Hui; Wang, Cheng; Gao, Lin; Zhao, Peiyi; Dong, Zhiqiang; Zhang, Jingting; Cui, Guohui; Wang, Sen; Han, Guolin; Zhao, Hui

    2015-01-01

    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 4 sink with an average annual methane absorption (negative emission) of 940.8 ± 103.2 g CH 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 −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 4 sink. • Increased nitrogen fertilisation and temperature led to higher CH 4 absorption. • CH 4 oxidation capacity showed a parabolic trend with soil moisture increased. • Crop rotation increased CH 4 absorption one time higher than continuous cropping. • A mechanism concept model of the CH 4 exchange in potato fields was advanced.

  20. Effect of contrasting crop rotation systems on soil chemical and biochemical properties and plant root growth in organic farming: First results

    Directory of Open Access Journals (Sweden)

    Elga Monaci

    2017-12-01

    Full Text Available Organic farming is claimed to improve soil fertility. Nonetheless, among organic practices, net C-inputs may largely vary in amount and composition and produce different soil conditions for microbial activity and plant-root system adaptation and development. In this study, we hypothesised that, in the regime of organic agriculture, soil chemical and biochemical properties can substantially differ under contrasting crop rotation systems and produce conditions of soil fertility to which the plant responds through diverse growth and production. The impact of 13 years of alfalfa-crop rotation (P-C and annual crop rotation (A-C was evaluated on the build up of soil organic carbon (SOC, active (light fraction organic matter, LFOM; water soluble organic carbon, WSOC and humic fraction [fulvic acids carbon (FAC, humic acids carbon (HAC], soil biochemical properties [microbial biomass carbon (MBC, basal respiration (dBR, alkaline phosphatase (AmP, arylsulfatase (ArS, orto-diphenoloxidase (o- DPO] and the amount of available macro-nutrients (N, P, and S at two different soil depths (0-10 cm and 10-30 cm before and after cultivation of wheat. We also studied the response of root morphology, physiology and yield of the plant-root system of wheat. Results showed that the level of soil fertility and plant-root system behaviour substantially differed under the two crop rotation systems investigated here. We observed high efficiency of the P-C soil in the build up of soil organic carbon, as it was 2.9 times higher than that measured in the A-C soil. With the exception of o-DPO, P-C soil always showed a higher level of AmP and ArS activity and an initial lower amount of available P and S. The P-C soil showed higher rootability and promoted thinner roots and higher root density. In the P-C soil conditions, the photosynthesis and yield of durum wheat were also favoured. Finally, cultivation of wheat caused an overall depletion of the accrued fertility of soil

  1. Influence of Conservation Tillage on some Soil Physical Properties and Crop Yield in Vetch-Wheat Rotation in Dryland Cold Region

    Directory of Open Access Journals (Sweden)

    I Eskandari

    2017-10-01

    Full Text Available Introduction Winter wheat is an important, well-adapted grain crop under dryland condition of the northwest of Iran. Soil water is the most limiting resource for crop growth in dryland areas. Therefore, farmers need to use crop residues and minimum tillage to control the soil erosion and effectively store and to use the limited precipitation received for crop production. Crop rotation and tillage system could affect crop yield due to their effects on water conservation and soil chemical and physical properties. Galantini et al., (2000 studied the effect of crop rotation on wheat productivity in the Pampean semi-arid region of Argentina and found that a wheat–vetch (Vicia sativa L. rotation resulted in higher yield and protein content, and greater yield components than the other rotations.Payne et al. (2000 stated that where precipitation amount is marginal (400 mm, dry field pea offers a potential alternative to summer fallowing. The purpose of this study was to identify the optimal tillage system for increasing crop productivity in a vetch–wheat rotation in dryland farming of the northwest of Iran. Materials and Methods The field experiment was carried out from 2010 to 2014 at the Dryland Agricultural Research Station (latitude37° 12´N; longitude 46◦20´E; 1730 m a.s.l., 25 km east of Maragheh, East Azerbaijan Province, Iran. The long-term (10 years average precipitation, temperature and relative humidity of the station are 336.5 mm, 9.4 ◦C and 47.5%, respectively. The soil (Fine Mixed, Mesic, Vertic Calcixerepts, USDA system; Calcisols, FAO system at the study site had a clay loam texture in the 0–15 cm surface layer and a clay texture in the 15–80 cm depth. This study was conducted in vetch (Vicia pannonica- wheat (Triticum aestivum L. rotation. The experiment was arranged in a randomized complete block design with four replications. The tillage treatments consisted of (1 conventional tillage: moldboard plowing followed by one

  2. Calagem em cultivos sucessivos de cenoura e alface Liming on crop rotation system of carrot and lettuce

    Directory of Open Access Journals (Sweden)

    Paulo E Trani

    2006-03-01

    Full Text Available A quantidade de calcário indicada de forma rotineira para hortaliças tem pouca experimentação de campo para dar suporte a níveis de aplicação. Neste trabalho procurou-se estabelecer valores para a saturação por bases (V e pH (CaCl2 para melhor produtividade e qualidade de cenoura (de inverno e alface (de verão, cultivadas sucessivamente por três anos agrícolas em um Argissolo Vermelho Amarelo em Monte Alegre do Sul (SP. Avaliou-se a calagem aplicada no ano, bem como o efeito residual da calagem no segundo e terceiro anos subseqüentes. Os tratamentos utilizados foram: 0; 2; 4; 6 e 8 t ha-1 de calcário no primeiro ano, e 4 e 8 t ha-1 de calcário no segundo e terceiro anos. Constatou-se efeito positivo da calagem sobre a produção e qualidade comercial da cenoura e da alface nos três anos agrícolas e efeito residual da calagem aplicada no primeiro ano do experimento sobre as produções de cenoura e alface nos anos seguintes. No primeiro ano, a produtividade de cenoura comercial foi de 24% a 39% maior do que a testemunha sem calcário, enquanto o peso médio da cabeça de alface aumentou de 79% a 199%. As maiores produtividades de cenoura foram de 46 t ha-1 obtidas com V=73% e pH (CaCl2= 5,7. As melhores produções de alface foram atingidas com V entre 72% e 80% e o pH (CaCl2 entre 5,5 e 5,6. A omissão de B, Cu, Mn e Zn em um dos tratamentos com calagem acarretou na queda de produtividade e qualidade da cenoura nos três anos agrícolas.Amounts of lime recommended for carrots and lettuce have little experimental support for the amounts indicated. This research was developed to determine the adequate value of soil bases saturation (V and pH (CaCl2 to obtain the best yield and commercial quality of carrot (winter and lettuce (summer cultivated on crop rotation system during three years. The experiment was carried out in Monte Alegre do Sul, São Paulo State, Brazil, on a Typic Kandaudult soil. The residual effect of liming, at the

  3. The gross- and net-irrigation requirements of crops and model farms with different root zone capacities at ten locations in Denmark 1990-2015

    DEFF Research Database (Denmark)

    ten Damme, Loraine; Andersen, Mathias Neumann

    abstraction permits for irrigation. Here we present estimates of the gross and net irrigation water requirements for a range of agricultural crops and model farms in 10 locations across Denmark for the years 1990-2015. We generally found higher values for the irrigation requirement than previous studies...... conducted 40 years ago. The annual irrigation water requirement varied according to farm type (dairy, arable/pig and potatoes), location,soil type and especially year with more than 300%. Abstraction permits based on average values are deemed less suitable as they may restrict farmers’ production in one out...

  4. Biogas from ley crops

    International Nuclear Information System (INIS)

    Dalemo, M.; Edstroem, M.; Thyselius, L.; Brolin, L.

    1993-01-01

    This report describes the cost of producing biogas from energy crops. Five process systems, sized 0.25-8 MW are studied. The cultivation of biogas-crops is made in three regions in Sweden. Also valued are the positive cultivation effects obtained when cereal dominated crop rotation is broken by biogas crops. 8 refs, 40 figs, 10 tabs

  5. Energy performances of intensive and extensive short rotation cropping systems for woody biomass production in the EU

    Czech Academy of Sciences Publication Activity Database

    Djomo, S. N.; Ač, Alexander; Zenone, T.; De Groote, T.; Bergante, S.; Facciotto, G.; Sixto, H.; Ciria Ciria, P.; Weger, J.; Ceulemans, R.

    2015-01-01

    Roč. 41, jan (2015), s. 845-854 ISSN 1364-0321 R&D Projects: GA MŠk EE2.3.30.0056 Institutional support: RVO:67179843 Keywords : poplar * willow * bioenergy crops * energy balance * energy efficiency Subject RIV: GC - Agronomy Impact factor: 6.798, year: 2015

  6. Cultivation-based and molecular assessment of bacterial diversity in the rhizosheath of wheat under different crop rotations

    NARCIS (Netherlands)

    Tahir, Muhammad; Mirza, M.S.; Hameed, Sohail; Rocha Dimitrov, Mauricio; Smidt, Hauke

    2015-01-01

    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

  7. Comparison of three types of oil crop rotation systems for effective use and remediation of heavy metal contaminated agricultural soil.

    Science.gov (United States)

    Yang, Yang; Zhou, Xihong; Tie, Boqing; Peng, Liang; Li, Hongliang; Wang, Kelin; Zeng, Qingru

    2017-12-01

    Selecting suitable plants tolerant to heavy metals and producing products of economic value may be a key factor in promoting the practical application of phytoremediation polluted soils. The aim of this study is to further understand the utilization and remediation of seriously contaminated agricultural soil. In a one-year field experiment, we grew oilseed rape over the winter and then subsequently sunflowers, peanuts and sesame after the first harvest. This three rotation system produced high yields of dry biomass; the oilseed rape-sunflower, oilseed rape-peanut and oilseed rape-sesame rotation allowed us to extract 458.6, 285.7, and 134.5 g ha -1 of cadmium, and 1264.7, 1006.1, and 831.1 g ha -1 of lead from soil, respectively. The oilseed rape-sunflower rotation showed the highest phytoextraction efficiency (1.98%) for cadmium. Lead and cadmium in oils are consistent with standards after extraction with n-hexane. Following successive extractions with potassium tartrate, concentrations of lead and cadmium in oilseed rape and peanut seed meals were lower than levels currently permissible for feeds. Thus, this rotation system could be useful for local farmers as it would enable the generation of income during otherwise sparse phytoremediation periods. Copyright © 2017. Published by Elsevier Ltd.

  8. Water balance, drought stress and yields for rainfed field crop rotations under present and future conditions in the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Hlavinka, Petr; Kersebaum, K. C.; Dubrovský, Martin; Fischer, Milan; Pohanková, Eva; Balek, Jan; Žalud, Zdeněk; Trnka, Miroslav

    2015-01-01

    Roč. 65, sep (2015), s. 175-192 ISSN 0936-577X R&D Projects: GA MŠk(CZ) EE2.3.20.0248; GA MŠk(CZ) LD13030; GA MŠk LD12029; GA MŠk(CZ) LO1415 Institutional support: RVO:68378289 ; RVO:67179843 Keywords : crop growth model * evapotranspiration * soil * climate change Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.690, year: 2015

  9. Containment of the western corn rootworm Diabrotica v.virgifera: continued successful management 2008 in southern Switzerland by monitoring and crop rotation.

    Science.gov (United States)

    Hummel, Hans E; Bertossa, M

    2009-01-01

    Diabrotica virgifera virgifera LeConte (Col.: Chrysomelidae), known as western corn rootworm (WCR) and endemic in North America, invaded Europe about two decades ago. Various unsuccessful attempts have been made to eradicate it from the Old World. Management with a variety of strategies is the option now remaining. WCR management in Southern Switzerland by a unique containment approach has been practiced successfully since 2003 using biotechnical means. Without any chemical pesticides or GMO input, the Swiss government mandated adherence to strict crop rotation. In addition to the economic benefits of this relatively simple approach, the environment was saved a considerable burden of pesticide applications. Other countries are invited to follow this example of sustainable pest management.

  10. 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.

  11. Evaluation of the CropSyst Model during Wheat-Maize Rotations on the North China Plain for Identifying Soil Evaporation Losses

    Science.gov (United States)

    Umair, Muhammad; Shen, Yanjun; Qi, Yongqing; Zhang, Yucui; Ahmad, Ayesha; Pei, Hongwei; Liu, Meiying

    2017-01-01

    The North China Plain (NCP) is a major grain production zone that plays a critical role in ensuring China's food supply. Irrigation is commonly used during grain production; however, the high annual water deficit [precipitation (P) minus evapotranspiration (ET)] in typical irrigated cropland does not support double cropping systems (such as maize and wheat) and this has resulted in the steep decline in the water table (~0.8 m year−1 at the Luancheng station) that has taken place since the 1970s. The current study aimed to adapt and check the ability of the CropSyst model (Suite-4) to simulate actual evapotranspiration (ETa), biomass, and grain yield, and to identify major evaporation (E) losses from winter wheat (WW) and summer maize (SM) rotations. Field experiments were conducted at the Luancheng Agro-ecosystem station, NCP, in 2010–2011 to 2012–2013. The CropSyst model was calibrated on wheat/maize (from weekly leaf area/biomass data available for 2012–2013) and validated onto measured ETa, biomass, and grain yield at the experimental station from 2010–2011 to 2011–2012, by using model calibration parameters. The revalidation was performed with the ETa, biomass, grain yield, and simulated ETa partition for 2008–2009 WW [ETa partition was measured by the Micro-lysimeter (MLM) and isotopes approach available for this year]. For the WW crop, E was 30% of total ETa; but from 2010–11 to 2013, the annual average E was ~40% of ETa for the WW and SM rotation. Furthermore, the WW and SM rotation from 2010–2011 to 2012–2013 was divided into three growth periods; (i) pre-sowing irrigation (PSI; sowing at field capacity) to emergence period (EP), (ii) EP to canopy cover period (CC) and (iii) CC to harvesting period (HP), and E from each growth period was ~10, 60, and 30%, respectively. In general, error statistics such as RMSE, Willmott's d, and NRMSE in the model evaluation for wheat ETa (maize ETa) were 38.3 mm, 0.81, and 9.24% (31.74 mm, 0.73, and 11

  12. Evaluation of the CropSyst Model during Wheat-Maize Rotations on the North China Plain for Identifying Soil Evaporation Losses

    Directory of Open Access Journals (Sweden)

    Muhammad Umair

    2017-09-01

    Full Text Available The North China Plain (NCP is a major grain production zone that plays a critical role in ensuring China's food supply. Irrigation is commonly used during grain production; however, the high annual water deficit [precipitation (P minus evapotranspiration (ET] in typical irrigated cropland does not support double cropping systems (such as maize and wheat and this has resulted in the steep decline in the water table (~0.8 m year−1 at the Luancheng station that has taken place since the 1970s. The current study aimed to adapt and check the ability of the CropSyst model (Suite-4 to simulate actual evapotranspiration (ETa, biomass, and grain yield, and to identify major evaporation (E losses from winter wheat (WW and summer maize (SM rotations. Field experiments were conducted at the Luancheng Agro-ecosystem station, NCP, in 2010–2011 to 2012–2013. The CropSyst model was calibrated on wheat/maize (from weekly leaf area/biomass data available for 2012–2013 and validated onto measured ETa, biomass, and grain yield at the experimental station from 2010–2011 to 2011–2012, by using model calibration parameters. The revalidation was performed with the ETa, biomass, grain yield, and simulated ETa partition for 2008–2009 WW [ETa partition was measured by the Micro-lysimeter (MLM and isotopes approach available for this year]. For the WW crop, E was 30% of total ETa; but from 2010–11 to 2013, the annual average E was ~40% of ETa for the WW and SM rotation. Furthermore, the WW and SM rotation from 2010–2011 to 2012–2013 was divided into three growth periods; (i pre-sowing irrigation (PSI; sowing at field capacity to emergence period (EP, (ii EP to canopy cover period (CC and (iii CC to harvesting period (HP, and E from each growth period was ~10, 60, and 30%, respectively. In general, error statistics such as RMSE, Willmott's d, and NRMSE in the model evaluation for wheat ETa (maize ETa were 38.3 mm, 0.81, and 9.24% (31.74 mm, 0.73, and 11

  13. Evaluation of the CropSyst Model during Wheat-Maize Rotations on the North China Plain for Identifying Soil Evaporation Losses.

    Science.gov (United States)

    Umair, Muhammad; Shen, Yanjun; Qi, Yongqing; Zhang, Yucui; Ahmad, Ayesha; Pei, Hongwei; Liu, Meiying

    2017-01-01

    The North China Plain (NCP) is a major grain production zone that plays a critical role in ensuring China's food supply. Irrigation is commonly used during grain production; however, the high annual water deficit [precipitation (P) minus evapotranspiration (ET)] in typical irrigated cropland does not support double cropping systems (such as maize and wheat) and this has resulted in the steep decline in the water table (~0.8 m year -1 at the Luancheng station) that has taken place since the 1970s. The current study aimed to adapt and check the ability of the CropSyst model (Suite-4) to simulate actual evapotranspiration (ET a ), biomass, and grain yield, and to identify major evaporation (E) losses from winter wheat (WW) and summer maize (SM) rotations. Field experiments were conducted at the Luancheng Agro-ecosystem station, NCP, in 2010-2011 to 2012-2013. The CropSyst model was calibrated on wheat/maize (from weekly leaf area/biomass data available for 2012-2013) and validated onto measured ET a , biomass, and grain yield at the experimental station from 2010-2011 to 2011-2012, by using model calibration parameters. The revalidation was performed with the ET a , biomass, grain yield, and simulated ET a partition for 2008-2009 WW [ET a partition was measured by the Micro-lysimeter (MLM) and isotopes approach available for this year]. For the WW crop, E was 30% of total ET a ; but from 2010-11 to 2013, the annual average E was ~40% of ET a for the WW and SM rotation. Furthermore, the WW and SM rotation from 2010-2011 to 2012-2013 was divided into three growth periods; (i) pre-sowing irrigation (PSI; sowing at field capacity) to emergence period (EP), (ii) EP to canopy cover period (CC) and (iii) CC to harvesting period (HP), and E from each growth period was ~10, 60, and 30%, respectively. In general, error statistics such as RMSE, Willmott's d , and NRMSE in the model evaluation for wheat ET a (maize ET a ) were 38.3 mm, 0.81, and 9.24% (31.74 mm, 0.73, and 11

  14. Assessment of the Spatial and Temporal Variations of Water Quality for Agricultural Lands with Crop Rotation in China by Using a HYPE Model

    Directory of Open Access Journals (Sweden)

    Yunxing Yin

    2016-03-01

    Full Text Available 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.

  15. Field assessment of the relative agronomic effectiveness of phosphate rock materials in a soybean - Maize crop rotation using 32P isotope techniques

    International Nuclear Information System (INIS)

    Mahisarakul, J.; Siripaibool, C.; Claimon, J.; Pakkong, P.

    2002-01-01

    Field experiments were conducted at Phrabudhabart Field Crop Research Station, Lopbur Province during the period 1995-1997 to determine the relative agronomic effectiveness (RAE) in a soybean- maize crop rotation using 32 P isotope techniques. The soil of the experimental site was the Pakchong soil series (Oxic Paleustults). Four PRs were applied at 120 kg P ha -1 , namely Algerian PR (ARPR), North Carolina PR from USA (NCPR), Petchaburi PR from Thailand (PBPR) and Ratchaburi PR from Thailand (RBPR) and TSP was added at three rates (40, 60, 120 kg P ha -1 ). For the first year harvest, soybeans absorbed more P from TSP fertilizer (% FPU) applied at 40 kg P ha -1 than maize, but there was no yield response. Among four PRs, North Carolina phosphate rock (NCPR) gave the highest % Pdff as well as the highest RAE. Maize was planted after soybean to study the residual effect of TSP and PRs. The results were the same as in soybean. In the second year (1996) the grain yield of soybean was higher than in the first year (1995), and there was significant response to P from TSP. The RAE of NCPR was very high. Maize showed the opposite results. In this case Algerian PR (ARPR) had the highest RAE. In 1997, TSP and six PRs (same four used in 1995 and 1996, Morocco PR (MCPR), and Lumphun PR (LPPR)) were applied at 60 kg P ha -1 . Phosphate rocks were applied either alone or in combination with TSP (50:50). Application of TSP resulted in high yields of soybean. In terms of RAE the P sources ranked as follows: LPPR+TSP>ARPR>LPPR> MCPR>NCPR+TSP>NCPR. The residual effect of P on the following maize crop resulted in a high RAE for MCPR and LPPR. It was concluded that TSP should be applied to every crop. The reactivity of PRs in the first and the second year experiments were: ARPR>NCPR>RBPR>PBPR. Morocco PR and LPPR were also reactive PRs in the third experiment. The combination of PR and TSP resulted in better P uptake (%Pdff). (author)

  16. Analysis of the energy efficiency of short rotation woody crops biomass as affected by different methods of soil enrichment

    International Nuclear Information System (INIS)

    Stolarski, Mariusz J.; Krzyżaniak, Michał; Tworkowski, Józef; Szczukowski, Stefan; Niksa, Dariusz

    2016-01-01

    The aim of this study was to determine the energy input and energy efficiency of the production of willow, poplar and black locust chips in four-year harvest rotation. The highest energy input was made in poplar production when soil was enriched with lignin and by mineral fertilisation (33.02 GJ ha −1 ). For willow production it was 30.76 GJ ha −1 when lignin, mycorrhiza and mineral fertilisation were used. The energy input in the production of black locust was much lower. The largest energy gain was obtained in the production of poplar when soil was enriched with lignin and mineral fertilisation (673.7 GJ ha −1 ). A similar level of this parameter (669.7 GJ ha −1 ) was achieved in the production of willow when lignin, mycorrhiza and mineral fertilisation was used. In general, a higher energy gain was obtained in the production of willow and poplar than in the production of black locust. On the other hand, the best energy efficiency ratio was achieved for willow (28.9) in the option with lignin. The ratio for poplar production ranged from 19.7 to 25.9. On the other hand, the energy efficiency ratio for black locust ranged from 10.6 to 21.7. - Highlights: • The energy input ranged from 6.69 GJ ha −1 to 33.02 GJ ha −1 . • The largest energy gain was obtained for poplar (673.7 GJ ha −1 ). • The best energy efficiency ratio was achieved for willow (28.9). • The energy efficiency ratio for poplar ranged from 19.7 to 25.9. • The energy efficiency ratio for black locust ranged from 10.6 to 21.7.

  17. Effect of display location on control-display stereotype strength for translational and rotational controls with linear displays.

    Science.gov (United States)

    Chan, Alan H S; Hoffmann, Errol R

    2015-01-01

    Experiments were designed to investigate the effects of control type and display location, relative to the operator, on the strength of control/display stereotypes. The Worringham and Beringer Visual Field principle and an extension of this principle for rotary controls (Hoffmann E.R., and Chan A.H.S. 2013). "The Worringham and Beringer 'Visual Field' Principle for Rotary Controls. Ergonomics." 56 (10): 1620-1624) indicated that, for a number of different control types (rotary and lever) on different planes, there should be no significant effect of the display location relative to the seated operator. Past data were surveyed and stereotype strengths listed. Experiments filled gaps where data are not available. Six different control types and seven display locations were used, as in the Frame of Reference Transformation Tool (FORT) model of Wickens et al. (Wickens, C.D., Keller, J.W., and Small, R.L. (2010). "Left. No, Right! Development of the Frame of Reference Transformation Tool (FORT)." Proceedings of the Human Factors and Ergonomics Society 54th Annual Meeting September 2010, 54: 1022-1026). Control/display arrangements with high stereotype strengths were evaluated yielding data for designers of complex control/display arrangements where the control and display are in different planes and for where the operator is moving. It was found possible to predict display/control arrangements with high stereotype strength, based on past data. Practitioner Summary: Controls and displays in complex arrangements need to have high compatibility. These experiments provide arrangements for six different controls (rotary and translational) and seven different display locations relative to the operator.

  18. Using Co-located Rotational and Translational Ground-Motion Sensors to Characterize Seismic Scattering in the P-Wave Coda

    Science.gov (United States)

    Bartrand, J.; Abbott, R. E.

    2017-12-01

    We present data and analysis of a seismic data collect at the site of a historical underground nuclear explosion at Yucca Flat, a sedimentary basin on the Nevada National Security Site, USA. The data presented here consist of active-source, six degree-of-freedom seismic signals. The translational signals were collected with a Nanometrics Trillium Compact Posthole seismometer and the rotational signals were collected with an ATA Proto-SMHD, a prototype rotational ground motion sensor. The source for the experiment was the Seismic Hammer (a 13,000 kg weight-drop), deployed on two-kilometer, orthogonal arms centered on the site of the nuclear explosion. By leveraging the fact that compressional waves have no rotational component, we generated a map of subsurface scattering and compared the results to known subsurface features. To determine scattering intensity, signals were cut to include only the P-wave and its coda. The ratio of the time-domain signal magnitudes of angular velocity and translational acceleration were sectioned into three time windows within the coda and averaged within each window. Preliminary results indicate an increased rotation/translation ratio in the vicinity of the explosion-generated chimney, suggesting mode conversion of P-wave energy to S-wave energy at that location. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc. for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-NA0003525.

  19. Location, Location, Location!

    Science.gov (United States)

    Ramsdell, Kristin

    2004-01-01

    Of prime importance in real estate, location is also a key element in the appeal of romances. Popular geographic settings and historical periods sell, unpopular ones do not--not always with a logical explanation, as the author discovered when she conducted a survey on this topic last year. (Why, for example, are the French Revolution and the…

  20. Location, location, location

    NARCIS (Netherlands)

    Anderson, S.P.; Goeree, J.K.; Ramer, R.

    1997-01-01

    We analyze the canonical location-then-price duopoly game with general log- concave consumer densities. A unique pure-strategy equilibrium to the two-stage game exists if the density is not "too asymmetric" and not "too concave." These criteria are satisfied by many commonly used densities.

  1. Production of Short-Rotation Woody Crops Grown with a Range of Nutrient and Water Availability: Establishment Report and First-Year Responses

    Energy Technology Data Exchange (ETDEWEB)

    D.R. Coyle; J. Blake; K. Britton; M.; R.G. Campbell; J. Cox; B. Cregg; D. Daniels; M. Jacobson; K. Johnsen; T. McDonald; K. McLeod; E.; D. Robison; R. Rummer; F. Sanchez; J.; B. Stokes; C. Trettin; J. Tuskan; L. Wright; S. Wullschleger

    2003-12-31

    Coleman, M.D., et. al. 2003. Production of Short-Rotation Woody Crops Grown with a Range of Nutrient and Water Availability: Establishment Report and First-Year Responses. Report. USDA Forest Service, Savannah River, Aiken, SC. 26 pp. Abstract: Many researchers have studied the productivity potential of intensively managed forest plantations. However, we need to learn more about the effects of fundamental growth processes on forest productivity; especially the influence of aboveground and belowground resource acquisition and allocation. This report presents installation, establishment, and first-year results of four tree species (two cottonwood clones, sycamore, sweetgum, and loblolly pine) grown with fertilizer and irrigation treatments. At this early stage of development, irrigation and fertilization were additive only in cottonwood clone ST66 and sweetgum. Leaf area development was directly related to stem growth, but root production was not always consistent with shoot responses, suggesting that allocation of resources varies among treatments. We will evaluate the consequences of these early responses on resource availability in subsequent growing seasons. This information will be used to: (1) optimize fiber and bioenergy production; (2) understand carbon sequestration; and (3) develop innovative applications such as phytoremediation; municipal, industrial, and agricultural wastes management; and protection of soil, air, and water resources.

  2. Aided phytoextraction of Cu, Pb, Zn, and As in copper-contaminated soils with tobacco and sunflower in crop rotation: Mobility and phytoavailability assessment.

    Science.gov (United States)

    Hattab-Hambli, Nour; Motelica-Heino, Mikael; Mench, Michel

    2016-02-01

    Copper-contaminated soils were managed with aided phytoextraction in 31 field plots at a former wood preservation site, using a single incorporation of compost (OM) and dolomitic limestone (DL) followed by a crop rotation with tobacco and sunflower. Six amended plots, with increasing total soil Cu, and one unamended plot were selected together with a control uncontaminated plot. The mobility and phytoavailability of Cu, Zn, Cr and As were investigated after 2 and 3 years in soil samples collected in these eight plots. Total Cu, Zn, Cr and As concentrations were determined in the soil pore water (SPW) and available soil Cu and Zn fractions by DGT. The Cu, Zn, Cr and As phytoavailability was characterized by growing dwarf beans on potted soils and determining the biomass of their plant parts and their foliar ionome. Total Cu concentrations in the SPW increased with total soil Cu. Total Cu, Zn, Cr and As concentrations in the SPW decreased in year 3 as compared to year 2, likely due to annual shoot removals by the plants and the lixiviation. Available soil Cu and Zn fractions also declined in year 3. The Cu, Zn, Cr and As phytoavailability, assessed by their concentration and mineral mass in the primary leaves of beans, was reduced in year 3. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Efeito da mucuna e amendoim em rotação com algodoeiro A study on crop rotation for cotton using velvet bean and peanut

    Directory of Open Access Journals (Sweden)

    Carlos A. M. Ferraz

    1977-01-01

    podzolized soils on calcareous sandstone Lins variation and an other in a soil without Fusarium (Presidente Venceslau, State of São Paulo in dark red latosol sandy phase. IAC RM3 is Fusarium wilt resistant and IAC 12-2 is wilt susceptible. A split-plot design with six replications was used. The small plots were the rotation combinations with velvet bean, peanut, IAC RM3, and IAC 12-2. These crops were planted during 1967/68 and 1969/70. The large plots were made up by wilt resistant cotton and wilt susceptible cotton, planted during 1968/69, 1970/71, 1971/72 and 1972/73. Data of 1968/69 showed that velvet bean and peanut were the best rotations at the two localities. There was no significant residual effect of rotation observed between 1971 and 1973. Rotation increased potassium level in the soil especially in the case of velvet bean.

  4. Effect of crop residue management and cropping system on pearl ...

    African Journals Online (AJOL)

    Retaining crop residues in the field and using legume-based crop rotations have been suggested as ways to simultaneously increase yields per unit area and replenish soil nutrients. The objective of this study was to investigate the influence of two cropping systems and three crop residue management practices on grain ...

  5. 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 (ptillage and compaction, increasing and decreasing the amount of the largest pores in CT and DD, respectively, but resulting in a proportionally larger pore space with relevant pore-sizes for water dynamics and agronomic performance. Significant differences in water retention and equivalent pore-sizes at the dry end of the WRC could be associated with the higher organic matter content found in DD. These results explain the superior performance of DD over CT in satisfying

  6. The effect of cover crop and crop rotation on soil water storage and on sorghum yield Efeito de cultura de cobertura e de rotação de cultura no armazenamento de água do solo e no rendimento de sorgo

    Directory of Open Access Journals (Sweden)

    Demóstenes Marcos Pedrosa de Azevedo

    1999-03-01

    Full Text Available Crop rotation and cover crop can be important means for enhancing crop yield in rainfed areas such as the lower Coastal Bend Region of Texas, USA. A trial was conducted in 1995 as part of a long-term cropping experiment (7 years to investigate the effect of oat (Avena sativa L. cover and rotation on soil water storage and yield of sorghum (Sorghum bicolor L.. The trial design was a RCB in a split-plot arrangement with four replicates. Rotation sequences were the main plots and oat cover crop the subplots. Cover crop reduced sorghum grain yield. This effect was attributed to a reduced concentration of available soil N and less soil water storage under this treatment. By delaying cover termination, the residue with a high C/N acted as an N sink through competition and/or immobilization instead of an N source to sorghum plants. Crop rotation had a significantly positive effect on sorghum yield and this effect was attributed to a significantly larger amount of N concentration under these rotation sequences.Rotação de cultura e cultura de cobertura constituem importantes meios para melhoria do rendimento de culturas em áreas de sequeiro como a região "Coastal Bend" do Estado do Texas. Um ensaio foi conduzido em 1995, como parte de um experimento de longa duração (7 anos, com o objetivo de investigar o efeito da aveia (Avena sativa L. como cultura de cobertura, e da rotação de cultura, no armazenamento da água do solo e no rendimento do sorgo (Sorghum bicolor L.. O delineamento experimental adotado foi o de blocos ao acaso, em parcelas subdivididas, com quatro repetições. As rotações foram alocadas nas parcelas, e a cultura de cobertura, nas subparcelas. A cultura de cobertura reduziu o rendimento do sorgo. Este efeito foi atribuído à reduzida concentração de N disponível do solo. Por atraso no extermínio e incorporação da aveia, seu resíduo, com elevada relação C/N, atuou como dreno, pela imobilização, em lugar de ser fonte

  7. Nuclear methods for plant nutrient and water balance studies. Results of an FAO/IAEA regional technical co-operation programme on nuclear methods for plant nutrients and water balance studies under legume-cereal or fallow-cereal crop rotation systems implemented for Middle Eastern countries (1991-1994)

    International Nuclear Information System (INIS)

    1996-04-01

    In semi-arid Middle Eastern countries, the increasing demand for food and other agricultural products calls for urgent measures to increase plant nutrient availability and water use efficiency. Water and plant nutrients are the two main crop yield limiting factors in these regions. Improved methods must be developed to sustain crop productivity of the legume-cereal rotation systems. It has been recognized for years that the growth of leguminous crops can improve the N status of the soil through biological nitrogen fixation (BNF). The conditions to improve the efficiency of the fixation process should be further investigated in order to fully benefit from this cheap N source. The BNF process is especially interesting for those areas facing limited fertilizer N availability or where the price of the fertilizers is too high for the farmers. In view of sustainable productivity, even with adequate supply of nutrients (nitrogen) and water, crop rotations have been promoted for years. However, the best rotation, taking into account the available nutrients and water in a specific place, is not always known. Furthermore, if a leguminous crop can be incorporated into a crop rotation system, free N is provided for this crop and some of it can serve as residual N for the next crop in the rotation. The use of 15 N technology provides a unique tool to separately study the behaviour of fertilizer N as well as soil N. In addition, the quantification of residual fertilizer N is possible, as well as the quantification of BNF. Refs, figs, tabs

  8. Effects of rotation of cotton (Gossypium hirsutum L.) and soybean [Glycine max (L.) Merr.] crops on soil fertility in Elizabeth, Mississippi, USA

    Science.gov (United States)

    The effects of cotton (Gossypium hirsutum L.):soybean [Glycine max (L.) Merr.] rotations on the soil fertility levels are limited. An irrigated soybean:cotton rotation experiment was conducted from 2012 through 2015 near Elizabeth, MS. Rotation sequences were; continuous soybean, continuous cotton...

  9. Estrategias de fertilización fosforada en una rotación de cultivos en el sudeste bonaerense Phosphorus fertilization strategies in a Buenos Aires southeast crop rotation

    Directory of Open Access Journals (Sweden)

    Guillermo Adrián Divito

    2010-07-01

    la aplicación anual y a la rotación, respectivamente. Se encontró una débil asociación entre la variación anual en el nivel de P-Bray y el balance de P correspondiente al cultivo implantado dicho año. Para el tratamiento testigo, se elaboró un modelo para predecir la disminución en el P disponible considerando el nivel inicial de P-Bray y la exportación de P de los cultivos como variables.In the soils of southeast Buenos Aires, fertilizer phosphorus (P forms medium to high solubility products, making it possible to define different fertilization strategies based on application frequency. The effect of P application rates capable of fulfilling all crop requirements in intensive rotations in the region is unknown. The objectives of this work were to: (1 assess yields in crops fertilized with P annually and once during the crop rotation and (2 determine P use efficiency and P recovery for each fertilization strategy. The experiment was conducted at the E.E.A. I.N.T.A. Balcarce on a Typic Argiudoll and Petrocalcic Paleudoll complex, under no-tillage and with high P-Bray (Bray & Kurts, 1945 content (28.7 mg kg-1. During the two rotation cycles for maize, soybean, and double wheat/soybean crop, three treatments were assessed: application of P annually, application once during the rotation cycle, and a control without P application. The experimental design was in randomized blocks with four repetitions. No crop yield differences were found between annual and rotation fertilization strategies across the two cycles evaluated. The control crop yield did not differ from the fertilized crop during the first rotation cycle but did during the second. The crop rotation P use efficiency (EUProt did not differ between nutrient applications strategies (19.4 and 32.4 kg kg-1 during the first cycle and 32.9 and 37.4 kg kg-1 during the second for annually and rotation fertilized treatments respectively. There were no differences between strategies in the crop P use efficiency

  10. Atributos físicos de um Latossolo Vermelho e produtividade de culturas cultivadas em sucessão e rotação Physical properties of an Oxisol and crops yield under succession and rotation

    Directory of Open Access Journals (Sweden)

    Silvio Aymone Genro Junior

    2009-02-01

    Full Text Available Este estudo objetivou avaliar os efeitos da sucessão e rotação de culturas nos atributos físicos e na produtividade dos cultivos agrícolas de um Latossolo Vermelho sob plantio direto, localizado no Estado do Rio Grande do Sul. Os tratamentos contaram de quatro seqüências de culturas cultivadas de 1998 a 2001: 1 sucessão trigo / soja; 2 rotação milho / aveia / milho+guandu anão / trigo / soja / trigo; 3 rotação guandu anão / trigo / soja / trigo / soja / aveia; e 4 rotação Crotalária / trigo / soja / aveia / milho / trigo. Em outubro de 2000 e de 2001, foram coletadas amostras de solo para determinar os atributos físicos do solo. Em todas as safras foi medida a produtividade das culturas. O Latossolo Vermelho cultivado com plantio direto apresenta um grau de compactação elevado, com densidade do solo acima e volume de macroporos abaixo do limite crítico para a classe textural muito argiloso. As maiores limitações ocorrem abaixo da camada de 0 a 0,03m, pois na camada mais superficial, apesar das pressões exercidas, a mobilização do solo nas operações de semeadura e adubação em linha aumenta a porosidade e reduz a densidade do solo. Nessa camada, houve maior volume de poros entre a saturação e a capacidade de campo, responsáveis pela aeração do solo, e entre a capacidade de campo e o ponto de murcha permanente, responsáveis pelo armazenamento da água disponível para as plantas. A introdução de plantas de cobertura a cada três anos não foi eficiente para reduzir a compactação. A produtividade das culturas foi influenciada positivamente na rotação com Crotalária, enquanto os demais sistemas não diferiram da sucessão de culturas.This study had as objective to evaluate the effects of crops succession and rotation on physical properties and crops yield on an Oxisol (clayey Haplortox under no tillage system, in Rio Grande do Sul State, Brazil. The treatments included four cropping sequences, used from 1998

  11. Environmental effectiveness of GAEC cross-compliance standard 2.2 "Maintaining the level of soil organic matter through crop rotation" and economic evaluation of the competitiveness gap for farmers

    Directory of Open Access Journals (Sweden)

    Lamberto Borrelli

    2015-11-01

    Full Text Available Within the Project MO.NA.CO was evaluated the Environmental effectiveness of GAEC cross-compliance standard 2.2 “Maintaining the level of soil organic matter through crop rotation” and economic evaluation of the competitiveness gap for farmers who support or not the cross-compliance regime. The monitoring was performed in nine experimental farms of the Council for Agricultural Research and Economics (CREA distributed throughout Italy and with different soil and climatic conditions. Were also evaluated the soil organic matter and some yield parameters, in a cereal monocropping (treatment counterfactual and a two-year rotation cereal-legume or forage (treatment factual. The two-years application of the standard “crop rotations” has produced contrasting results with regards to the storage of soil organic matter through crop rotation and these were not sufficient to demonstrate a statistically significant effect of treatment in any of the farms considered in monitoring, only in those farms subjected to more years of monitoring was recorded only a slight effect of the standard as a trend. The variations of organic matter in soils in response to changes in the culture technique or in the management of the soil may have long lag times and two years of time are not sufficient to demonstrate the dynamics of SOM associated with the treatment, also in consideration of the large inter annual variability recorded in different monitored sites.

  12. Identical location transmission electron microscopy in combination with rotating disc electrode measurements. The activity of fuel cell catalysts and their degradation

    Energy Technology Data Exchange (ETDEWEB)

    Schloegl, Katrin G.

    2011-07-13

    As an alternative to conventional combustion engines, the Proton Exchange Membrane Fuel Cell (PEMFC) using hydrogen as a fuel is a promising concept owing to its potential independence from fossil fuels, high efficiency and zero emissions. Concerning its commercial viability, the fundamental problem of high system cost per power output and lifetime is closely related to finding more active and stable catalysts for the oxygen reduction reaction. In the presented work, several methods are combined to examine the parameters and processes responsible for both activity and degradation of platinum-based catalysts. Degradation mechanisms are scrutinized by means of electrochemical measurements with the rotating disc electrode in combination with a recently developed TEM technique, which allows for the comparison of identical locations before and after accelerated stress tests. (orig.) [German] Die mit Wasserstoff betriebene Proton Exchange Membrane Brennstoffzelle (PEMFC) stellt aufgrund ihrer potentiellen Unabhaengigkeit von fossilen Energietraegern, ihrem hohen Wirkungsgrad und fehlendem Schadstoffausstoss eine vielversprechende Alternative zum konventionellen Verbrennungsmotor dar. Das grundlegende Problem der zu hohen Systemkosten und zu geringen Lebensdauer fuer kommerzielle Anwendungen ist eng mit der Entwicklung aktiverer und stabiler Elektrokatalysatoren fuer die Sauerstoffreduktion verknuepft. In der vorliegenden Arbeit werden verschiedene Methoden kombiniert, um die Parameter und Prozesse zu untersuchen, welche fuer die Aktivitaet und Degradation platinbasierter Katalysatoren verantwortlich sind. Zur Aufklaerung vorliegender Degradationsmechanismen werden elektrochemische Messungen mit der rotierenden Scheibenelektrode in Kombination mit einer neu entwickelten TEM Methode eingesetzt, welche es ermoeglicht, identische Stellen vor und nach beschleunigten Degradationstests zu untersuchen.

  13. Tile drain losses of nitrogen and phosphorus from fields under integrated and organic crop rotations. A four-year study on a clay soil in southwest Sweden.

    Science.gov (United States)

    Stenberg, Maria; Ulén, Barbro; Söderström, Mats; Roland, Björn; Delin, Karl; Helander, Carl-Anders

    2012-09-15

    In order to explore the influence of site-specific soil properties on nitrogen (N) and phosphorus (P) losses between individual fields and crop sequences, 16 drained fields with clay soils were investigated in a four-year study. Mean total N (TN) loss was 6.6-11.1 from a conventional, 14.3-21.5 from an organic and 13.1-23.9 kg ha(-1) year(-1) from an integrated cropping system across a 4 year period, with 75% in nitrate form (NO(3)-N). Mean total P (TP) loss was 0.96-3.03, 0.99-4.63 and 0.76-2.67 kg ha(-1) year(-1), from the three systems respectively during the same period, with 25% in dissolved reactive form (DRP). Median N efficiency was calculated to be 70% including gains from estimated N fixation. According to principal component factor (PCA) analysis, field characteristics and cropping system were generally more important for losses of N and P than year. Accumulation of soil mineral N in the autumn and (estimated) N fixation was important for N leaching. No P fertilisers were used at the site in either cropping system. Total P concentration in drainage water from each of the fields was marginally significantly (pleguminous crops needs to be considered carefully when designing cropping systems high efficiency in N utilisation and low environmental impact. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Evaluation of long-term conservation agriculture and crop intensification in rice-wheat rotation of Indo-Gangetic Plains of South Asia: Carbon dynamics and productivity.

    Science.gov (United States)

    Samal, S K; Rao, K K; Poonia, S P; Kumar, Rakesh; Mishra, J S; Prakash, Ved; Mondal, S; Dwivedi, S K; Bhatt, B P; Naik, Sushanta Kumar; Choubey, Anup Kumar; Kumar, V; Malik, R K; Mc Donald, Andrew

    2017-10-01

    In the context of deteriorating soil health, stagnation of yield in rice-wheat cropping system (RWCS) across Indo- Gangetic plains (IGP) and environmental pollution, a long term field experiment was conducted during 2009-2016 taking four crop scenarios with conservation agriculture (CA), crop intensification and diversified cropping as intervening technology aiming to evaluate the sustainability of the systems. Scenario 1 (S1) represented conventional farmers' practice of growing rice and wheat with summer fallow. In scenario 2 (S2) and scenario 3 (S3), legume crop was taken along with rice and wheat with partial CA and full CA, respectively. Conventional RWCS was replaced with rice-potato + maize- cowpea cropping system with partial CA in scenario 4 (S4). The S3 scenario registered highest total organic carbon (TOC) stock of 47.71 Mg C ha -1 and resulted in significant increase of 14.57% over S1 (Farmer's practice) in 0-30 cm soil depth after 7 years of field trial. The S4 scenario having intensified cropping systems recorded lowest TOC of 39.33 Mg C ha -1 and resulted in significant depletion of 17.56% in C stock with respect to S3 in 0-30 cm soil depth. The TOC enrichment was higher in S2, S3 and S4 scenario in the surface soil (0-10 cm) compared to S1. At lower depth (20-30 cm), the TOC enrichment was significantly higher in S2 (12.82 Mg C ha -1 ) and S3 (13.10 Mg C ha -1 soil) over S1 scenario. The S2 and S3 scenario recorded highest increased allocation of TOC (3.55 and 6.13 Mg C ha -1 ) to passive pool over S1. The S2 (15.72 t ha -1 ), S3 (16.08 t ha -1 ) and S4 (16.39 t ha -1 ) scenarios recorded significantly higher system rice equivalent yield over S1 (10.30 t ha -1 ). Among the scenarios, S3 scenario had greater amount of total soil organic carbon, passive pool of carbon and higher system rice equivalent yield, thus, is considered the best cropping management practice to maintain soil health and food security in the middle IGP.

  15. Effect of crop residue harvest on long-term crop yield, soil erosion, and carbon balance: tradeoffs for a sustainable bioenergy feedstock

    Energy Technology Data Exchange (ETDEWEB)

    Gregg, Jay S.; Izaurralde, Roberto C.

    2010-08-26

    Agricultural residues are a potential feedstock for bioenergy production, if residue harvest can be done sustainably. The relationship between crop residue harvest, soil erosion, crop yield and carbon balance was modeled with the Erosion Productivity Impact Calculator/ Environment Policy Integrated Climate (EPIC) using a factorial design. Four crop rotations (winter wheat [Triticum aestivum (L.)] – sunflower [Helianthus annuus]; spring wheat [Triticum aestivum (L.)] – canola [Brassica napus]; corn [Zea mays L.] – soybean [Glycine max (L.) Merr.]; and cotton [Gossypium hirsutum] – peanut [Arachis hypogaea]) were simulated at four US locations each, under different topographies (0-10% slope), and management practices [crop residue removal rates (0-75%), conservation practices (no till, contour cropping, strip cropping, terracing)].

  16. Multimodel Inference for the Prediction of Disease Symptoms and Yield Loss of Potato in a Two-Year Crop Rotation Experiment

    NARCIS (Netherlands)

    Berg, van den W.; Vos, J.; Grasman, J.

    2012-01-01

    The second order Akaike information criterion was used for the assessment of 139 regression models for three responses of potato test crops: (a) incidence of Spongospora subterranea on the harvested tubers, (b) percentage of haulms infected with Verticillium dahliae, and (c) tuber yield. Six

  17. Residues of Avermectin B1a in rotational crops and soils following soil treatment with [14C]Avermectin B1a

    International Nuclear Information System (INIS)

    Moye, H.A.; Malagodi, M.H.; Yoh, H.; Leibee, G.L.; Ku, C.C.; Wislocki, P.G.

    1987-01-01

    [ 14 C]Avermectin B 1 a was applied twelve times to muck and sandy loam soils and three times to sandy soil at 0.025-0.030 lb/acre per application. These applications simulated the intended use of avermectin B 1 a on celery, vegetables, and cotton, respectively. Following three aging periods in each soil type, sorghum, lettuce, and carrot or turnip seeds were planted and harvested at one-fourth, half, and full size. Analysis of these crops by oxidative combustion demonstrated that crops grown in muck, sandy loam, and sandy soils contained radiolabeled residues ranging from below the limit of quantitation (BLQ) to 7.4 μg/kg of avermectin B 1 a equivalents, BLQ to 11.6 μg/kg, and BLQ to 3.54 μg/kg, respectively. There was a general trend of decreasing residue concentrations with increasing preharvest intervals in crops grown in all soils. The radioactivity present in muck and sandy loam soils disappeared with half-lives ranging from 103 to 267 days and from 102 to 132 days, respectively

  18. Sistemas de preparo do solo e rotação de culturas na produtividade de milho, soja e trigo Tillage systems and crop rotation on yield of corn, soybean and wheat

    Directory of Open Access Journals (Sweden)

    Pedro M. da Silveira

    2003-08-01

    Full Text Available Com este trabalho, objetivou-se determinar quanto os sistemas de preparo do solo e as rotações de culturas afetam a produtividade de grãos do milho, da soja e do trigo. O experimento foi conduzido em um Latossolo Vermelho distrófico, em área irrigada por pivô central, na EMBRAPA Arroz e Feijão, em Santo Antônio de Goiás, GO, por seis anos, setembro de 1992 a setembro de 1998, durante os quais foram feitos 12 cultivos e comparados três sistemas de preparo do solo: a aração com arado de aiveca, realizada em novembro-dezembro e em maio-junho; b aração com grade aradora, em ambos os períodos, e c plantio direto e quatro rotações de cultura: 1 milho-feijão; 2 soja-trigo; 3 soja-trigo-soja-feijão-arroz-feijão e 4 milho-feijão-milho-feijão-arroz-feijão. As culturas de arroz, soja e milho, foram semeadas em novembro-dezembro e as de feijão e trigo, em maio-junho. Para efeito do estudo, consideraram-se somente as culturas do milho, da soja e do trigo. O sistema de preparo do solo não afetou a produtividade de soja mas, sim, a de milho e de trigo, tendo o preparo com arado propiciado maiores produtividades em comparação com o plantio direto. As diferenças entre o plantio direto e os demais sistemas de preparo do solo, com relação à produtividade acumulada relativa de milho, diminuíram com o tempo de cultivo. Não houve efeito da rotação de culturas sobre a produtividade das culturas estudadas.The objective of this study was to determine how much soil tillage and crop rotation affected grain yield of corn, soybean and wheat. The study was carried out at EMBRAPA (Rice and Beans, in Santo Antônio de Goiás, GO, Brazil, in a Red Latosol (Oxisol, under center pivot irrigation system, for six consecutive years. During the experimentation, 12 crops were cultivated. The tillage treatments were a moldboard plough, b harrow disc and c no-tillage. The crop rotations were 1 corn-bean, 2 soybean-wheat, 3 soybean

  19. Infiltração de água no solo sob escarificação e rotação de culturas Water infiltration in soil as influenced by chiseling and crop rotations

    Directory of Open Access Journals (Sweden)

    Maryara Buriola Prando

    2010-06-01

    Full Text Available Nos solos com restrições físicas e, ou, físico-hídricas ao crescimento de raízes, aumentar o potencial de armazenagem de água por meio de melhorias na infiltração pode ser uma estratégia viável para aumento da produtividade das culturas. Nesse sentido, este trabalho teve como objetivo avaliar a infiltração de água em um Nitossolo Vermelho distrófico, com três sistemas de rotação de culturas sob semeadura direta com e sem escarificação inicial. O sistema de rotação de culturas constou de: (1 milheto/soja/sorgo/milho/sorgo (M/S/So/Mi/So, (2 milheto/soja/Brachiaria ruziziensis/milho/Brachiaria ruziziensis (M/S/B/Mi/B e (3 milheto/soja/Brachiaria ruziziensis + mamona/milho/Brachiaria ruziziensis + mamona (M/S/B+Ma/Mi/B+Ma. A infiltração de água no solo foi avaliada em campo com anéis concêntricos instalados na superfície, a 0,10 e 0,20 m de profundidade, em 2006 e 2007. Após o primeiro ano, o manejo com escarificação inicial do solo apresentou a maior infiltração de água. A rotação Brachiaria ruziziensis + mamona proporcionou maior infiltração da água no solo. A atividade do sistema radicular das espécies nas parcelas sem escarificação inicial aumentou a velocidade de infiltração da água no solo.In soils with physical and/or physical hydric restrictions for root growth, it may be a viable strategy to increase crop productivity by increasing water storage potential through improvements in water infiltration. Accordingly, the objective of this study was to determine water infiltration in a Hapludult in three crop rotations under no-tillage, with and without initial chiseling. Crop rotations consisted of: millet/soybean/sorghum/maize/sorghum; millet/soybean/Brachiaria ruziziensis/corn/Brachiaria ruziziensis; and millet/soybean/Brachiaria ruziziensis + castor bean/corn/Brachiaria ruziziensis + castor bean. Water infiltration in soil was evaluated in the field, using concentric discs at the soil surface and at

  20. Multimodel Inference for the Prediction of Disease Symptoms and Yield Loss of Potato in a Two-Year Crop Rotation Experiment

    Directory of Open Access Journals (Sweden)

    Wim Van den Berg

    2012-01-01

    Full Text Available The second order Akaike information criterion was used for the assessment of 139 regression models for three responses of potato test crops: (a incidence of Spongospora subterranea on the harvested tubers, (b percentage of haulms infected with Verticillium dahliae, and (c tuber yield. Six variables that are likely related to the response variables were taken into consideration: soil infestations of the fungus Verticillium dahliae and of three nematode species (Globodera pallida, Trichodoridae, and Meloidogyne spp. and, furthermore, soil pH and water soluble phosphor (P. Interactions between V. dahliae and the three nematode species were included as well. Based on multimodelling, predictors are given a weight from which one may decide about the need to include them in a prediction of crop yield. The most important predictors were soil infestation levels of V. dahliae and G. pallida and soil pH. The outcome also showed that tubers suffered more from S. subterranea for higher soil pH values. Finally, yield reduction from the presence of V. dahliae was enhanced by the presence of higher densities of G. pallida.

  1. Relación entre el cultivo antecesor y la disponibilidad de nitrógeno para el trigo en la rotación Relationship between the preceding crop and nitrogen availability for wheat in the rotation

    Directory of Open Access Journals (Sweden)

    Guillermo Alberto Studdert

    2006-07-01

    aims of this work were to evaluate i wheat relative (to the maximum obtained in the corresponding experiment and year yields (RR and aboveground dry matter (MSR and N accumulation (NR in time after different preceding crops, and ii the relationship between RR, MSR and NR variation and soil organic matter content changes. In two long term crop rotation experiments at Balcarce (on a complex of Typic Argiudoll and Petrocalcic Paleudoll the variation of RR, MSR and VR along years under cropping with conventional tillage, was analyzed. The preceding crops were potato (Solanum tuberosum L., soybean (Glycine max L. Merr., wheat, sunflower (Helianthus annuus L. and maize (Zea mays L.. All three variables showed a decrease along cropping years, but up to different levels according to which had been the preceding crop. Residue characteristics and/or the way they had been managed before wheat seeding made that RR, MSR and NR after soybean, potato and wheat were higher. On the other hand, wheat RR, MSR, NR after maize were the lowest. These effects were associated with the role of residues on N mineralization-immobilization cycle. In general, the variation in wheat RR, MSR and NR along cropping years was not associated with changes in soil organic matter due to soil management under cropping. The short term effect of preceding crop residues and of its management on N dynamics defined the amount and timing of the availability of N for wheat. This was independently of the effect of the rotation on the capability of the soil to mineralize N due to how the residues intervene on the cycle mineralization-immobilization.

  2. Combinable protein crop production

    OpenAIRE

    Wright, Isobel

    2008-01-01

    This research topic review aims to summarise research knowledge and observational experience of combinable protein crop production in organic farming systems for the UK. European research on peas, faba beans and lupins is included; considering their role in the rotation, nitrogen fixation, varieties, establishment, weed control, yields, problems experienced and intercropping with cereals.

  3. Sustainable Agriculture: Cover Cropping

    Science.gov (United States)

    Webster, Megan

    2018-01-01

    Sustainable agriculture practices are increasingly being used by farmers to maintain soil quality, increase biodiversity, and promote production of food that is environmentally safe. There are several types of sustainable agriculture practices such as organic farming, crop rotation, and aquaculture. This lesson plan focuses on the sustainable…

  4. Danish farmer’s perception of GM-crops

    DEFF Research Database (Denmark)

    Søndergaard, Janus; Pedersen, Søren Marcus; Gylling, Morten

    2005-01-01

    This paper presents a study of 185 farmer’s perception of GM-crops in Denmark. The respondent’s attitude to GM-crops mainly reflects a conservative view of the adoption of GM-crops. Among farmers only the exciting crops in rotation is seen as their future potential GM-crops. Findings from...

  5. Eficiência agronômica de superfosfato triplo e fosfato natural de Arad em cultivos sucessivos de soja e milho Agronomic efficiency of triple superphosphate and Arad rock phosphate on crop rotation of soybean and corn

    Directory of Open Access Journals (Sweden)

    Fábio Benedito Ono

    2009-06-01

    Full Text Available Conduziu-se este estudo, com o objetivo de avaliar os efeitos de doses de adubos fosfatados sobre a cultura da soja e do milho, em cultivos sucessivos. O experimento foi realizado em casa de vegetação da UFGD, em vasos contendo amostras de 5,5 dm³ de um Latossolo Vermelho Distroférrico argiloso, sendo utilizado como fontes de fósforo (P o superfosfato triplo (SFT e o fosfato natural de Arad (FNA. O FNA foi utilizado sob duas formas. Em uma, considerou-se o P total (Arad T e, em outra, apenas a fração de P solúvel em ácido cítrico a 2% (Arad SA, resultando em três fatores de estudo, cada um em seis níveis de P (0, 56, 112, 224, 336 e 560, expressos em mg dm-3. A soja foi semeada em dezembro de 2006 e ao final do ciclo, efetuou-se a colheita, avaliando-se a produtividade de grãos, teores de P na folha e no solo. Após o cultivo da soja, semeou-se o milho, cuja colheita das plantas ocorreu aos 76 dias após a semeadura, sendo avaliados a produção de massa seca da parte aérea e teores de P na folha. O índice de eficiência agronômica foi calculado para ambas as culturas. Conclui-se que, para o primeiro cultivo (soja, o SFT apresentou um melhor desempenho no que se refere à produtividade de grãos, quando comparado ao FNA. No cultivo do milho em sucessão a soja, o FNA tendeu a equiparar-se ao SFT nos atributos avaliados.The aim of this study was to evaluate the effects of phosphate fertilizer rates on soybean and corn crops, in crop rotation. The experiment was carried out in a greenhouse at the Grande Dourados University, in pots with samples of 5.5 dm³ clayey Dystropherric Red Latosol, where the triple superphosphate (TSP and the Arad rock phosphate (ARP were used as P source. Two kinds of ARP were used. In one, the total P (Arad T was considered while in the other, only the P soluble fraction in citric acid at the concentration of 2% (Arad SA was considered, resulting in three factors of study, each with six levels of P (0, 56

  6. The use of 32P radioisotope techniques for evaluating the relative agronomic effectiveness of phosphate rock materials in a soybean-maize crop rotation in acid soils of Thailand

    International Nuclear Information System (INIS)

    Mahisarakul, J.; Pakkong, P.

    2002-01-01

    A series of greenhouse experiments was conducted over three years to evaluate the relative agronomic effectiveness (RAE) of phosphate rock materials in a soybean - maize crop sequence, using 32 P isotope dilution techniques. For the first two years, the crops were grown in a pot experiment in four acid soils of Thailand. In the first year, four increasing rates of TSP and one rate of four phosphate rocks (PRs) were used. The PRs used were Algerian PR, North Carolina PR, Petchaburi PR, and Ratchaburi PR. Soybean did not respond to P application from TSP, while there was good response in maize which was planted after soybean (1st residual effect). The percent P derived from TSP or PR fertilizer (%Pdff) had the following order: Warin soil > Mae Tang soil > Rangsit soil > Pakchong soil for soybean and Warin soil > Pakchong soil > Rangsit soil > Mae Tang soil for maize. In the second year, the soybean - maize rotation was replanted to study the residual effect of TSP and PRs, both applied at 180 mg P kg -1 . No significant response of soybean and maize to TSP was found in terms of dry matter yield. In terms of %Pdff and %RAE the soils ranked as follows: Rangsit soil > Pakchong soil Mae Tang soil > Warin soil for soybean and Warin soil > Rangsit soil > Mae Tang > Pakchong soil for maize. Both crops absorbed more P from TSP than from PRs. The %RAE in the 2nd year experiment was higher than %RAE in the 1st year In the third year, TSP and two PRs were applied at one P rate to Pakchong and Warin soils. The applied PRs were North Carolina PR (NCPR) and Lamphun phosphate rock (LPPR). PRs were applied either alone or in combination with TSP (50:50). Soybean was planted first, followed by maize. The P-response in terms of dry matter yield and %Pdff was highly significant in both soils. The RAE ranked as follows: TSP > NCPR + TSP > LPPR + TSP > NCPR > LPPR. Maize showed the same trend in RAE as soybean in both soils. The RAE for both crops was highest in Warin soil. (author)

  7. Experimental warming-driven soil drying reduced N2O emissions from fertilized crop rotations of winter wheat-soybean/fallow, 2009-2014

    DEFF Research Database (Denmark)

    Liu, L; Hu, C; Yang, P

    2016-01-01

    Nitrous oxide (N2O) emissions from agricultural soils play an important role in the global greenhouse gas budget. However, the response of N2O emissions from nitrogen fertilized agricultural soils to climate warming is not yet well understood. A field experiment with simulated warming (T) using i...... nitrogen and organic matter, which consequently accelerated N cycle dynamics and advanced wheat growth.......Nitrous oxide (N2O) emissions from agricultural soils play an important role in the global greenhouse gas budget. However, the response of N2O emissions from nitrogen fertilized agricultural soils to climate warming is not yet well understood. A field experiment with simulated warming (T) using...... infrared heaters and its control (C) combined with a nitrogen (N1) fertilization treatment (315 kg N ha−1 y−1) and no nitrogen treatment (N0) was conducted over five years at an agricultural research station in the North China Plain in a winter wheat–soybean double cropping system. N2O fluxes were measured...

  8. Vertical migration of {sup 60}Co, {sup 137}Cs and {sup 226}Ra in agricultural soils as observed in lysimeters under crop rotation

    Energy Technology Data Exchange (ETDEWEB)

    Shinonaga, T. [Division of Environmental and Life Science, ARC Seibersdorf Research, A-2444 Seibersdorf (Austria)]. E-mail: t.shinonaga@iaea.org; Schimmack, W. [Institute of Radiation Protection, GSF-National Research Center for Environment and Health, D-85764 Neuherberg (Germany); Gerzabek, M.H. [Division of Environmental and Life Science, ARC Seibersdorf Research, A-2444 Seibersdorf (Austria); Department for Forest and Soil Sciences, University of Natural Resources and Applied Life Science, Gregor-Mendel-Strasse 33, A-1180 Vienna (Austria)

    2005-07-01

    In most studies quantifying the migration parameters - apparent migration velocity and apparent dispersion coefficient - of radionuclides in the soil by model calculations, these parameters are determined for undisturbed soils. For soils disturbed by ploughing, however, no such data are available in the literature. Therefore, in the present study, the migration parameters of {sup 137}Cs, {sup 60}Co and {sup 226}Ra were estimated for ploughed soils by means of a convection-dispersion model. The depth distributions of the radionuclides were determined in four lysimeters (area: 1 m{sup 2}, depth of soil monolith: 0.75 m) filled with artificially contaminated soils of different types in July 1990. The lysimeters were cropped with agricultural plants. The soil in each lysimeter was ploughed manually once a year until 1996 (plough depth 20 cm). In July 1999, soil samples were collected from three pits in each lysimeter. The depth distributions of all radionuclides proved to be very similar in each soil pit. The spatial variability of the depth distributions of a given radionuclide within the lysimeters was about the same as their variability between the four lysimeters. Evaluation of the migration parameters revealed that the convective transport of the radionuclides was always rather small or even zero, while the dispersive transport caused a 'melting' process of the initially sharp activity edge at the lower border of the Ap horizon. These results are explained by the high evapotranspiration (80-90% of the total precipitation plus irrigation) and the small amounts of seepage water during the observation period of 9 years.

  9. Limited Impact of a Fall-Seeded, Spring-Terminated Rye Cover Crop on Beneficial Arthropods.

    Science.gov (United States)

    Dunbar, Mike W; Gassmann, Aaron J; O'Neal, Matthew E

    2017-04-01

    Cover crops are beneficial to agroecosystems because they decrease soil erosion and nutrient loss while increasing within-field plant diversity. Greater plant diversity within cropping systems can positively affect beneficial arthropod communities. We hypothesized that increasing plant diversity within annually rotated corn and soybean with the addition of a rye cover crop would positively affect the beneficial ground and canopy-dwelling communities compared with rotated corn and soybean grown without a cover crop. From 2011 through 2013, arthropod communities were measured at two locations in Iowa four times throughout each growing season. Pitfall traps were used to sample ground-dwelling arthropods within the corn and soybean plots and sweep nets were used to measure the beneficial arthropods in soybean canopies. Beneficial arthropods captured were identified to either class, order, or family. In both corn and soybean, community composition and total community activity density and abundance did not differ between plots that included the rye cover crop and plots without the rye cover crop. Most taxa did not significantly respond to the presence of the rye cover crop when analyzed individually, with the exceptions of Carabidae and Gryllidae sampled from soybean pitfall traps. Activity density of Carabidae was significantly greater in soybean plots that included a rye cover crop, while activity density of Gryllidae was significantly reduced in plots with the rye cover crop. Although a rye cover crop may be agronomically beneficial, there may be only limited effects on beneficial arthropods when added within an annual rotation of corn and soybean. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Rotação de culturas: análise estatística de um experimento de longa duração em Campinas (SP Crop rotation: a statistical analysis of an eleven years experiment in Campinas, State of São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Francisco Lombardi-Neto

    2002-08-01

    Full Text Available Com o objetivo de determinar o efeito da rotação no rendimento das culturas de algodão, amendoim, arroz, cana-de-açúcar e milho, instalou-se em Campinas, São Paulo, Brasil, um experimento avaliado durante 11 anos (1963/64 a 1974/75, seguido de análise do efeito residual dessa prática (1975/76, tomando, como indicador da fertilidade do solo, o rendimento de grãos de milho, semeado em todas as parcelas. No planejamento do experimento, em blocos casualizados com vinte tratamentos e quatro repetições, considerou-se que todos os tratamentos devem estar presentes em todos os anos, a fim de avaliar com eficiência e maior rapidez o efeito da rotação. Os resultados evidenciaram que as culturas contínuas, apenas com adubação mineral, levaram à redução significativa da produção no decorrer dos anos. Os tratamentos com calagem inicial e adubação mineral anual mantiveram a produtividade média, apesar das grandes oscilações anuais da produção. O efeito da rotação, quando praticada com calagem inicial e adubação mineral anual, levou a uma produtividade satisfatória ao longo dos anos, bem superior à do cultivo contínuo de cada uma das culturas, principalmente quando as culturas anuais não receberam a calagem inicial.With the goal of determining the crop rotation effects on cotton, peanut, rice, sugar cane and maize yields, a rotation experiment was established in Campinas, State of São Paulo, Brazil, for eleven years (1963/64 to 1974/75. The residual effect was determined by planting maize on all experimental plots in the following year (1975/76. The experimental design was randomized blocks with twenty treatments and four replications, spanning all treatments in all years in order to have an efficient and faster evaluation of the crop rotation effects. The results showed that the continuous cropping with mineral fertilizer applied annually led to a significant decrease of crop yield. However, when this continuous cropping

  11. Effect of Nutrient Management Planning on Crop Yield, Nitrate Leaching and Sediment Loading in Thomas Brook Watershed

    Science.gov (United States)

    Amon-Armah, Frederick; Yiridoe, Emmanuel K.; Ahmad, Nafees H. M.; Hebb, Dale; Jamieson, Rob; Burton, David; Madani, Ali

    2013-11-01

    Government priorities on provincial Nutrient Management Planning (NMP) programs include improving the program effectiveness for environmental quality protection, and promoting more widespread adoption. Understanding the effect of NMP on both crop yield and key water-quality parameters in agricultural watersheds requires a comprehensive evaluation that takes into consideration important NMP attributes and location-specific farming conditions. This study applied the Soil and Water Assessment Tool (SWAT) to investigate the effects of crop and rotation sequence, tillage type, and nutrient N application rate on crop yield and the associated groundwater leaching and sediment loss. The SWAT model was applied to the Thomas Brook Watershed, located in the most intensively managed agricultural region of Nova Scotia, Canada. Cropping systems evaluated included seven fertilizer application rates and two tillage systems (i.e., conventional tillage and no-till). The analysis reflected cropping systems commonly managed by farmers in the Annapolis Valley region, including grain corn-based and potato-based cropping systems, and a vegetable-horticulture system. ANOVA models were developed and used to assess the effects of crop management choices on crop yield and two water-quality parameters (i.e., leaching and sediment loading). Results suggest that existing recommended N-fertilizer rate can be reduced by 10-25 %, for grain crop production, to significantly lower leaching ( P > 0.05) while optimizing the crop yield. The analysis identified the nutrient N rates in combination with specific crops and rotation systems that can be used to manage leaching while balancing impacts on crop yields within the watershed.

  12. Modelling of the transfer of CS-137 from air to crops, milk, beef and human body following the Chernobyl accident, in a location in Central Bohemia. Test of the model PRYMA T1

    International Nuclear Information System (INIS)

    Carrasco, E.; Garcia-Olivares, A.; Suanez, A.; Robles, B. Simon, I.; Cancio, D.

    1994-01-01

    This work was made in the frame of the research programme on validation of models for the transfer of radionuclides in the terrestrial, urban and aquatic environments. The acronym of this programme is VAMP (Validation of Model Predictions) and is coordinated by the International Atomic Energy Agency (IAEA) and the Commission of the European Communities (CEC). The scenario was named CB and was presented by the Multiple Pathway Working group. The scenario description was at the beginning a blind test, that is without knowing the location or the measured concentrations and doses. The input information included data of contamination in Cs-137 from the Chernobyl accident in Central Europe, in air and soils and more description of the scenario (data about crops, cattele, demography, human diet, etc.). The aim of the exercise was the contrast between model results and between observed data and model predictions. In this work the results obtained by the CIEMAT-IMA group of modelers are shown and discussed

  13. Upland rice yield as affected by previous summer crop rotation (soybean or upland rice and glyphosate management on cover crops Produtividade do arroz de terras altas afetada pela rotação de cultura e pelo manejo de glifosato nas plantas de cobertura do solo

    Directory of Open Access Journals (Sweden)

    A.S Nascente

    2013-03-01

    Full Text Available The appropriate chemical management of cover crops in no-tillage aims to obtain greater benefits with its employment in agricultural systems. The objective of this study was to assess upland rice yield as affected by the previous summer crop, species and desiccation timing of cover crops by glyphosate. Sown cover crops were sown (November 2007, followed by rice in half of the experimental area and soybean in the other half (November 2008. After the harvesting of these crops, the same cover crops were sown again (March 2009 and followed by upland rice in the total area (November 2009. The experiment consisted of the combination of five cover crops (fallow, Panicum maximum, Brachiaria ruziziensis, B. brizantha and Pennisetum glaucum, four desiccation timings (30, 20, 10 and 0 days before rice sowing, and two antecedents of the summer crop (rice or soybean under no-tillage system (NTS, plus two control treatments at conventional tillage system (CTS. Cover crops significantly affect rice grain yield and its components. There is a significant tendency to highest yield when cover crop desiccation is conducted farther from the rice sowing date (from 2,577.1 kg ha-1 - desiccation at rice sowing to 3,115.30 kg ha-1 - desiccation 30 days before rice sowing. Soybean as an antecedent of summer crop allows better upland rice yield (3,754 kg ha-1 than rice as an antecedent of summer crop (2,635 kg ha-1; fallow/soybean/fallow (4,507 kg ha-1 and millet/soybean/millet (4,765 kg ha-1 rotation at no-tillage system, and incorporated fallow /soybean/ incorporated fallow (4,427 kg ha-1 at conventional tillage system allow the highest rice yield; upland rice yield is similar at no-till (3,194 kg ha-1 and till system (2,878 kg ha-1.O correto manejo químico das plantas de cobertura visa obter maiores benefícios com a sua introdução nos sistemas agrícolas. O objetivo deste estudo foi avaliar como a produção do arroz de terras altas é afetada pela safra de ver

  14. RENDIMENTO DO FEIJOEIRO IRRIGADO EM ROTAÇÃO COM CULTURAS GRANÍFERAS E ADUBOS VERDES YIELD OF IRRIGATED COMMON BEAN IN ROTATION WITH GRAIN AND GREEN MANURE CROPS

    Directory of Open Access Journals (Sweden)

    ELAINE BAHIA WUTKE

    1998-01-01

    State, Brazil, in a typic Haplorthox soil. The experimental design was a randomized complete block with six treatments and six replications. The rotation schemes consisted of irrigated common bean from July to December, followed by an early variety of corn, from December to April and by fallow, corn, oats (Avena strigosa, sunnhemp (Crotalaria juncea L., pigeonpea [Cajanus cajan (L. Millsp.] and velvet beans (Mucuna aterrima, from March to August. The soil nutrient contents at 0-20 cm depth, were reduced during the three year period, being normal for organic matter and medium for phosphorus, potassium, calcium and magnesium. The medium to high acidity level did not restrict the grain yield of common beans. The inclusion of velvet bean, sunnhemp and corn in rotation with common bean and corn is feasible. These crops produced the greatest amounts of green matter. The basic infiltration rate of the soil was also increased. There was an effect of the rotations during the years with the inclusion of velvet bean, in the non-conventional Autumn-Winter season, which increased the grain yield of irrigated common beans in relation to the fallow treatment.

  15. 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

  16. Short rotation coppice for energy production: hydrological guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Hall, R.L.

    2003-07-01

    This report provides hydrological guidelines for growers, land and water resource managers, environmental groups and other parties interested in utilising short rotation coppice (SRC) for energy production. The aim of the report is to help interested parties decide if a location is suitable for SRC planting by considering whether potential hydrological impacts will have an adverse effect on crop productivity and yield. The guidelines consider: the water use of SRC compared with other crops; the factors governing water use; the water requirements for a productive crop; and the likely impacts on the availability and quantity of water. The report points out that there are still gaps in our knowledge of the processes controlling the water use and growth of SRC and notes that, in some situations, there will be considerable uncertainty in predictions.

  17. Effect of Mixed Systems on Crop Productivity

    Science.gov (United States)

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

    2017-04-01

    The goals of this non-irrigated research has been to determine the effect of mixed systems integration on crop, soil, and beef cattle production in the northern Great Plains region of the United States. Over a 5-year period, growing spring wheat (HRSW-C) continuously year after year was compared to a 5-year crop rotation that included spring wheat (HRSW-R), cover crop (dual crop consisting of winter triticale/hairy vetch seeded in the fall and harvested for hay followed by a 7-species cover crop that was seeded in June after hay harvest), forage corn, field pea/barley, and sunflower. Control 5-year HRSW yield was 2690 kg/ha compared to 2757 kg/ha for HRSW grown in rotation. Available soil nitrogen (N) is often the most important limitation for crop production. Expensive fertilizer inputs were reduced in this study due to the mixed system's complementarity in which the rotation system that included beef cattle grazing sustained N availability and increased nutrient cycling, which had a positive effect on all crops grown in the rotation. Growing HRSW continuously requires less intensive management and in this research was 14.5% less profitable. Whereas, when crop management increased and complementing crops were grown in rotation to produce crops and provide feed for grazing livestock, soil nutrient cycling improved. Increased nutrient cycling increased crop rotation yields and yearling beef cattle steers that grazing annual forages in the rotation gain more body weight than similar steers grazing NGP native range. Results of this long-term research will be presented in a PICO format for participant discussion.

  18. Effect of integrated forage rotation and manure management on yield, nutrient balance and soil organic matter

    Directory of Open Access Journals (Sweden)

    Cesare Tomasoni

    2011-03-01

    Full Text Available This paper reports results from a field experiment established in 1995 and still on going. It is located in Lodi, in the irrigated lowlands of Lombardy, Northern Italy. The experiment compares two rotations: the annual double cropping system, Italian ryegrass + silage maize (R1; and the 6-year rotation, in which three years of double crop Italian ryegrass + silage maize are followed by three years of alfalfa harvested for hay (R6 Each rotation have received two types of dairy manure: i farmyard manure (FYM; ii semi-liquid manure (SLM. The intent was to apply to each unit land area the excreta produced by the number of adult dairy cows sustained, in terms of net energy, by the forage produced in each rotation, corresponding to about 6 adult cows ha-1 for R1 and 4 adult cows ha-1 for R6. Manure was applied with (N1 or without (N0 an extra supply of mineral N in the form of urea. The objectives of this study were: i to assess whether the recycling of two types of manure in two forage rotation systems can sustain crop yields in the medium and long term without additional N fertilization; ii to evaluate the nutrient balance of these integrated forage rotations and manure management systems; iii to compare the effects of farmyard manure and semi-liquid manure on soil organic matter. The application of FYM, compared to SLM, increased yield of silage maize by 19% and alfalfa by 23%, while Italian ryegrass was not influenced by the manure treatment. Yet, silage maize produced 6% more in rotation R6 compared to rotation R1. The mineral nitrogen fertilization increased yield of Italian ryegrass by 11% and of silage maize by 10%. Alfalfa, not directly fertilized with mineral nitrogen, was not influenced by the nitrogen applied to the other crops in rotation. The application of FYM, compared to SLM, increased soil organic matter (SOM by +37 % for the rotation R1, and by +20% for the rotation R6. Conversely, no significant difference on SOM was observed

  19. Yields of crops on a rhodic ferralsol in southern Brazil in relation to ...

    African Journals Online (AJOL)

    Even though no-tillage, crop rotation management systems have been accepted as useful for sustaining crop production, there is the need to identify which crops can be used for such rotations. This study evaluated the dry matter and grain yields of eight winter and two summer crops (maize, Zea mays L. and soybean, ...

  20. 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

  1. 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.

  2. 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

  3. Produtividade do algodoeiro herbáceo em plantio direto no Cerrado com rotação de culturas Herbaceous cotton yield in no-till system in rainfed Savannah conditions with crop rotation

    Directory of Open Access Journals (Sweden)

    José Carlos Corrêa

    2004-01-01

    Full Text Available O experimento, instalado em um Latossolo Vermelho-Amarelo muito argiloso, teve o objetivo de avaliar o efeito da rotação de culturas na produtividade do algodoeiro herbáceo (Gossypium hirsutum L. r. latifolium Hutch em plantio direto sob condições de sequeiro no Cerrado. O delineamento experimental foi de blocos casualizados com cinco tratamentos e quatro repetições. Os tratamentos consistiram das rotações soja-milheto-soja-milheto-algodoeiro; soja-amaranto-soja-nabo forrageiro-soja-algodoeiro; soja-sorgo granífero-soja-sorgo granífero-algodoeiro; soja-aveia preta-soja-aveia preta-algodoeiro e soja-soja-algodoeiro. A maior produtividade do algodoeiro foi obtida com a rotação de soja e milheto, em que houve melhor controle de plantas daninhas.The experiment was carried out in a heavy red yellow latosol and aimed at evaluating crop rotation on herbaceous cotton yields in no-till system under rainfed Savannah conditions. The experimental design used was a completely randomised blocks with five treatments: soybean-millet-soybean-millet-cotton; soybean-amaranth-soybean-forage radish-soybean-cotton; soybean-grain sorghum-soybean-grain sorghum-cotton; soybean-black rye-soybean-black rye-cotton and soybean-soybean-cotton and four replications. The highest cotton seed yield was obtained in the sequence soybean-millet-soybean-millet-cotton, in which best weed control also occurred.

  4. ROTAT, a tool for systematically generating crop rotations

    NARCIS (Netherlands)

    Dogliotti Moro, S.; Rossing, W.A.H.; Ittersum, van M.K.

    2003-01-01

    This paper reports part of a methodology for a model-based exploration of land use motivated by the lack of sustainability of small farming systems in southern Uruguay. Explorative land use studies aim to gain insight into future possibilities for agricultural development. They support strategic

  5. 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

    -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...

  6. Rotational seismology

    Science.gov (United States)

    Lee, William H K.

    2016-01-01

    Rotational seismology is an emerging study of all aspects of rotational motions induced by earthquakes, explosions, and ambient vibrations. It is of interest to several disciplines, including seismology, earthquake engineering, geodesy, and earth-based detection of Einstein’s gravitation waves.Rotational effects of seismic waves, together with rotations caused by soil–structure interaction, have been observed for centuries (e.g., rotated chimneys, monuments, and tombstones). Figure 1a shows the rotated monument to George Inglis observed after the 1897 Great Shillong earthquake. This monument had the form of an obelisk rising over 19 metres high from a 4 metre base. During the earthquake, the top part broke off and the remnant of some 6 metres rotated about 15° relative to the base. The study of rotational seismology began only recently when sensitive rotational sensors became available due to advances in aeronautical and astronomical instrumentations.

  7. Alternative crops

    International Nuclear Information System (INIS)

    Andreasen, L.M.; Boon, A.D.

    1992-01-01

    Surplus cereal production in the EEC and decreasing product prices, mainly for cereals, has prompted considerable interest for new earnings in arable farming. The objective was to examine whether suggested new crops (fibre, oil, medicinal and alternative grains crops) could be considered as real alternatives. Whether a specific crop can compete economically with cereals and whether there is a market demand for the crop is analyzed. The described possibilities will result in ca. 50,000 hectares of new crops. It is expected that they would not immediately provide increased earnings, but in the long run expected price developments are more positive than for cereals. The area for new crops will not solve the current surplus cereal problem as the area used for new crops is only 3% of that used for cereals. Preconditions for many new crops is further research activities and development work as well as the establishment of processing units and organizational initiatives. Presumably, it is stated, there will then be a basis for a profitable production of new crops for some farmers. (AB) (47 refs.)

  8. Modelling of the transfer of Cs-137 from air to crops, milk, beef and human body following the Chernobyl accident in a location in Central Bohemia. Test of the model PRYMA T1

    International Nuclear Information System (INIS)

    Carrasco, E.; Garcia-Olivares, A.; Suanez, A.; Robles, B.; Simon, I.; Cancio, D.

    1994-01-01

    This work was made in the frame of the research programme on validation od models for the transfer of radionuclides in the terrestrial, urban and aquatic environments. the acronym of this programme is VAMP (Validation of Model Predictions) and is co-ordinated by the International Atomic energy Agency (IAEA) and the Commission of the european Communities (CEC). The scenario was named CB and Was presented by the Multiple Pathway Working group. the scenario description was at the beginning a blind test, that is without knowing the location or the measured concentrations and doses. the input information included data of contamination in Cs-137 from the Chernobyl accident in Central Europe, in air and soils and ore, description of the scenario (data about crops, cattle, demography, human diet, etc.). the aim of the exercise was the contrast between model results and between observed data and model predictions. In this work the results obtained by the CIEMAT-IMA group of modelers are shown and discussed. (Author) 24 refs

  9. Modelling of the transfer of Cs-137 from air to crops, milk, beef and human body following the Chernobyl accident in a location in Central Bohemia. Test of the model PRYMA T1

    Energy Technology Data Exchange (ETDEWEB)

    Carrasco, E.; Garcia-Olivares, A.; Suanez, A.; Robles, B.; Simon, I.; Cancio, D.

    1994-07-01

    This work was made in the frame of the research programme on validation od models for the transfer of radionuclides in the terrestrial, urban and aquatic environments. the acronym of this programme is VAMP (Validation of Model Predictions) and is co-ordinated by the International Atomic energy Agency (IAEA) and the Commission of the european Communities (CEC). The scenario was named CB and Was presented by the Multiple Pathway Working group. the scenario description was at the beginning a blind test, that is without knowing the location or the measured concentrations and doses. the input information included data of contamination in Cs-137 from the Chernobyl accident in Central Europe, in air and soils and ore, description of the scenario (data about crops, cattle, demography, human diet, etc.). the aim of the exercise was the contrast between model results and between observed data and model predictions. In this work the results obtained by the CIEMAT-IMA group of modelers are shown and discussed. (Author) 24 refs.

  10. Assessing ecological risks and benefits of genetically modified crops

    OpenAIRE

    Bošković Jelena V.; Isajev Vasilije V.; Prijić Željana S.; Zečević Veselinka M.; Hojka Zdravko M.; Dozet Gordana K.

    2010-01-01

    Genetically modified (GM) crops and biotechnology are providing new opportunities for increasing crop productivity and tackling agriculture problems, such as diseases, pests and weeds, abiotic stress and nutritional limitations of staple food crops. As GM crops are being adopted in various locations with different ecosystems, a scientifically based understanding of the environmental effects of cultivations of GM crops would assist decision makers worldwide ...

  11. 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 reason......, crop management technologies have been developed, with a special focus on the Mediterranean region, to enhance crop production by increasing land productivity and sustaining soil fertility under influence of climate changes and population increases. The main objective of this study was to analyse...... dryland Mediterranean cropping systems, and to discuss and recommend sustainable cropping technologies that could be used at the small-scale farm level. Four crop management practices were evaluated: crop rotations, reduced tillage, use of organic manure, and supplemental and deficit irrigation. Among...

  12. Engineering Sclerotinia Sclerotiorum Resistance in Oilseed Crops ...

    African Journals Online (AJOL)

    The fungal pathogen Sclerotinia sclerotiorum (Lib.) de Bary is worldwide in distribution and pathogenic to more than 400 plant species. This disease causes significant yield losses of various important crops including sunflower, canola, and soybean. Applying fungicides and crop rotation are currently the major methods of ...

  13. Introducción de cultivos de cobertura en la rotación soja-maíz: efecto sobre algunas propiedades del suelo Inclusion of cover crops in a soybean-corn rotation: effect on some soil properties

    Directory of Open Access Journals (Sweden)

    Silvina Beatriz Restovich

    2011-07-01

    -tillage (NT show a progressive decline in their physical and chemical fertility. The inclusion of cover crops (CC in these agricultural systems could help mitigate these types of degradation. The objectives of this study were: 1 to evaluate the effect of different CC on some soil properties (porosity distribution, structural stability, bulk density, soil organic carbon (SOC and labile carbon and 2 to analyze the evolution of these properties during the inclusion of CC in a soybean-corn rotation under NT. In 2005, a two-year study was carried out on a silt loam Typic Argiudoll using different winter species as CC: barley (Hordeum vulgare L., ryegrass (Lolium multiflorum L., oats (Avena sativa L., rescue grass (Brumus unioloides L., vetch (Vicia sativa L., rape seed (Brassica napus L. and forage radish (Raphanus sativus L., a mixture of vetch and oats, and a control without CC. We measured an increase in soil macroporosity and structural stability and an increase in SOC content and the labile fraction. These changes were of moderate to low magnitude, occurring mainly near the soil surface (0-5 cm; they were associated with moments of important residue contributions and disappeared in periods of heavy rain. The rotations that included CC accumulated more SOC. Forage radish outstanded as a generator of porosity and oats as a stabilizer of the porous system.

  14. CROPS Clever Robots for Crops

    NARCIS (Netherlands)

    Bontsema, J.; Hemming, J.; Pekkeriet, E.J.

    2015-01-01

    In the EU-funded CROPS project robots are developed for site-specific spraying and selective harvesting of fruit
    and fruit vegetables. The robots are being designed to harvest crops, such as greenhouse vegetables, apples,
    grapes and for canopy spraying in orchards and for precision target

  15. Global rotation

    International Nuclear Information System (INIS)

    Rosquist, K.

    1980-01-01

    Global rotation in cosmological models is defined on an observational basis. A theorem is proved saying that, for rigid motion, the global rotation is equal to the ordinary local vorticity. The global rotation is calculated in the space-time homogeneous class III models, with Godel's model as a special case. It is shown that, with the exception of Godel's model, the rotation in these models becomes infinite for finite affine parameter values. In some directions the rotation changes sign and becomes infinite in a direction opposite to the local vorticity. The points of infinite rotation are identified as conjugate points along the null geodesics. The physical interpretation of the infinite rotation is discussed, and a comparison with the behaviour of the area distance at conjugate points is given. (author)

  16. Climate Impacts of Cover Crops

    Science.gov (United States)

    Lombardozzi, D.; Wieder, W. R.; Bonan, G. B.; Morris, C. K.; Grandy, S.

    2016-12-01

    Cover crops are planted in agricultural rotation with the intention of protecting soil rather than harvest. Cover crops have numerous environmental benefits that include preventing soil erosion, increasing soil fertility, and providing weed and pest control- among others. In addition to localized environmental benefits, cover crops can have important regional or global biogeochemical impacts by increasing soil organic carbon, changing emissions of greenhouse trace gases like nitrous oxide and methane, and reducing hydrologic nitrogen losses. Cover crops may additionally affect climate by changing biogeophysical processes, like albedo and latent heat flux, though these potential changes have not yet been evaluated. Here we use the coupled Community Atmosphere Model (CAM5) - Community Land Model (CLM4.5) to test how planting cover crops in the United States may change biogeophysical fluxes and climate. We present seasonal changes in albedo, heat fluxes, evaporative partitioning, radiation, and the resulting changes in temperature. Preliminary analyses show that during seasons when cover crops are planted, latent heat flux increases and albedo decreases, changing the evaporative fraction and surface temperatures. Understanding both the biogeophysical changes caused by planting cover crops in this study and the biogeochemical changes found in other studies will give a clearer picture of the overall impacts of cover crops on climate and atmospheric chemistry, informing how this land use strategy will impact climate in the future.

  17. Space/age forestry: Implications of planting density and rotation age in SRIC management decisions

    Energy Technology Data Exchange (ETDEWEB)

    Merriam, R.A.; Phillips, V.D.; Liu, W.

    1993-12-31

    Short-rotation intensive-culture (SRIC) of promising tree crops is being evaluated worldwide for the production of methanol, ethanol, and electricity from renewable biomass resources. Planting density and rotation age are fundamental management decisions associated with SRIC energy plantations. Most studies of these variables have been conducted without the benefit of a unifying theory of the effects of growing space and rotation age on individual tree growth and stand level productivity. A modeling procedure based on field trials of Eucalyptus spp. is presented that evaluates the growth potential of a tree in the absence and presence of competition of neighboring trees in a stand. The results of this analysis are useful in clarifying economic implications of different growing space and rotation age decisions that tree plantation managers must make. The procedure is readily applicable to other species under consideration for SRIC plantations at any location.

  18. Crop rotation biomass and arbuscular mycorrhizal fungi effects on sugarcane yield Produção de biomassa e presença de fungos micorrízicos arbusculares em culturas utilizadas em rotação com a cana-de-açúcar

    Directory of Open Access Journals (Sweden)

    Edmilson José Ambrosano

    2010-12-01

    Full Text Available A cana-de-açúcar (Saccharum spp. vem sendo cultivada no Brasil para produção de açúcar e agroenergia. Em seu sistema de produção, após um ciclo de 4 a 8 anos, é possível a rotação com plantas de cobertura, antes do seu replantio, para melhoria do solo e geração de renda. Estudou-se a caracterização e produtividade de biomassa de leguminosas (como adubos-verdes e girassol (Helianthus annuus L., a ocorrência natural de micorrizas, o teor de açúcar e a produtividade em colmos da cana-de-açúcar IAC 87-3396 e a viabilidade econômica desse sistema com cultivo após as opções de rotação, com quantificação da produtividade durante três cortes consecutivos. O amendoim (Arachis hypogaea L. cv. IAC-Caiapó, girassol cv. IAC-Uruguai e mucuna-preta (Mucuna aterrimum Piper and Tracy foram as culturas que apresentaram maior percentagem de colonização por fungos micorrízicos. O girassol foi a planta de cobertura que mais extraiu nutrientes do solo, seguido por amendoim (Arachis hipogaea L. cv. IAC-Tatu e feijão-mungo (Vigna radiata L. Wilczek. A colonização por fungos micorrízicos mostrou correlação positiva com a altura de plantas de cana no primeiro corte (p = 0,01 e R = 0,52, mas não se correlacionou com a produtividade de colmos ou açúcar. No primeiro corte, o girassol foi a cultura de rotação que ocasionou o maior aumento de produtividade, da ordem de 46% em colmos e de 50% na quantidade de açúcar, em comparação com a testemunha. Com exceção dos amendoins, todas as culturas em rotação aumentaram a renda líquida do sistema na média de três cortes de cana-de-açúcar.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

  19. 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

  20. Establishment and function of cover crops interseeded into corn

    Science.gov (United States)

    Cover crops can provide ecological services and improve the resiliency of annual cropping systems; however, cover crop use is low in corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] rotations in the upper Midwest due to challenges with establishment. Our objective was to compare three planting me...

  1. Canaryseed Crop

    Directory of Open Access Journals (Sweden)

    Maximiliano Cogliatti

    2012-03-01

    Full Text Available Canaryseed (Phalaris canariensis L. is a graminaceous crop species with production practices and cycle similar to those of other winter cereal crops such as spring wheat (Triticum aestivum L. and oat (Avena sativa L.. Currently its grains are used almost exclusively as feed for birds, alone or mixed with other grains like millet, sunflower seed, and flaxseed. Canaryseed is a genuine cereal with a unique composition that suggests its potential for food use. P. canariensis is cultivated in many areas of temperate climates. Currently, its production is concentrated in the southwestern provinces of Canada (Alberta, Saskatchewan and Manitoba and on a smaller scale in Argentina, Thailand and Australia. Globally it is considered to be a minor crop with regional relevance, with a production about of 250000 tonnes per year, which restricts private investment and public research on its genetic and technological improvement. For this reason, the type of crop management that is applied to this species largely depends on innovations made in other similar crops. This work provides an updated summary of the available information on the species: its requirements, distribution, genetic resources, cultivation practices, potential uses, marketing and other topics of interest to researchers and producers.

  2. Rotating Wavepackets

    Science.gov (United States)

    Lekner, John

    2008-01-01

    Any free-particle wavepacket solution of Schrodinger's equation can be converted by differentiations to wavepackets rotating about the original direction of motion. The angular momentum component along the motion associated with this rotation is an integral multiple of [h-bar]. It is an "intrinsic" angular momentum: independent of origin and…

  3. The rotator

    DEFF Research Database (Denmark)

    Jensen, Eva B. Vedel; Gundersen, Hans Jørgen Gottlieb

    1993-01-01

    The mean particle volume can be stereologically estimated using the nucleator principle. In the present paper, we discuss another principle for estimating mean particle volume, namely the rotator. The vertical rotator has already been previously described and is supplemented in the present paper ...

  4. Rotational elasticity

    Science.gov (United States)

    Vassiliev, Dmitri

    2017-04-01

    We consider an infinite three-dimensional elastic continuum whose material points experience no displacements, only rotations. This framework is a special case of the Cosserat theory of elasticity. Rotations of material points are described mathematically by attaching to each geometric point an orthonormal basis that gives a field of orthonormal bases called the coframe. As the dynamical variables (unknowns) of our theory, we choose the coframe and a density. We write down the general dynamic variational functional for our rotational theory of elasticity, assuming our material to be physically linear but the kinematic model geometrically nonlinear. Allowing geometric nonlinearity is natural when dealing with rotations because rotations in dimension three are inherently nonlinear (rotations about different axes do not commute) and because there is no reason to exclude from our study large rotations such as full turns. The main result of the talk is an explicit construction of a class of time-dependent solutions that we call plane wave solutions; these are travelling waves of rotations. The existence of such explicit closed-form solutions is a non-trivial fact given that our system of Euler-Lagrange equations is highly nonlinear. We also consider a special case of our rotational theory of elasticity which in the stationary setting (harmonic time dependence and arbitrary dependence on spatial coordinates) turns out to be equivalent to a pair of massless Dirac equations. The talk is based on the paper [1]. [1] C.G.Boehmer, R.J.Downes and D.Vassiliev, Rotational elasticity, Quarterly Journal of Mechanics and Applied Mathematics, 2011, vol. 64, p. 415-439. The paper is a heavily revised version of preprint https://arxiv.org/abs/1008.3833

  5. Rotation effects of grain and herbaceous legumes on maize yield ...

    African Journals Online (AJOL)

    Crop rotation with legumes and fallow has been known to enhance soil fertility and crop productivity. This prompted an investigation into the effects of some legumes and fallow on some soil chemical properties and yield of maize. The study was conducted in 2001 and 2002 on an Alfisol to determine the effects of crop ...

  6. CONVERSÃO E BALANÇO ENERGÉTICO DE SISTEMAS DE SUCESSÃO E DE ROTAÇÃO DE CULTURAS ENERGY CONVERSION AND BALANCE OF CROP SUCCESSION AND ROTATION SYSTEMS

    Directory of Open Access Journals (Sweden)

    Henrique Pereira dos Santos

    2001-04-01

    Full Text Available Do ponto de vista calórico, existem poucos trabalhos no Brasil estimando a conversão e o balanço energético. Neste estudo, avaliaram-se a conversão e o balanço energético de sete sistemas de rotação de culturas durante nove anos (1987 a 1995, em Passo Fundo, RS. Os sistemas foram constituídos por: sistema I (trigo/soja; sistema II (trigo/soja, de 1987 a 1989, e trigo/soja e ervilhaca/ milho ou sorgo, de 1990 a 1995; sistema III (trigo/soja, aveia preta ou aveia branca/soja e ervilhaca/milho ou sorgo; sistema IV (trigo/soja, aveia branca/soja, linho/soja e ervilhaca/milho, de 1987 a 1989, e trigo/soja, girassol ou aveia preta/soja, aveia branca/soja e ervilhaca/milho ou sorgo, de 1990 a 1995; sistema V (trigo/soja, trigo/soja, aveia preta ou aveia branca/soja e ervilhaca/milho ou sorgo; sistema VI (trigo/ soja, trigo/soja, aveia branca/soja, linho/soja e ervilhaca/milho, de 1987 a 1989, e trigo/soja, trigo/soja, girassol ou aveia preta/soja, aveia branca/soja e ervilhaca/milho ou sorgo, de 1990 a 1995; e VII (pousio de inverno/soja, de 1990 a 1995. No período agrícola de 1987 a 1989, não houve diferenças significativas entre os sistemas de rotação de culturas, em relação à conversão energética e ao balanço energético. Na média do período de 1990 a 1995, o sistema II (8,58 apresentou índice de conversão energética maior do que o do sistema I (5,61, e os demais sistemas não diferiram significativamente entre si. No mesmo período, o balanço energético para os sistemas II (20.938Mcal/ha, III (19.239Mcal/ha, IV (18.618Mcal/ha, V (19.646kg/Mcal e VI (18.702Mcal/ha foi superior ao do sistema VII (10.279Mcal/ha. A rotação de culturas foi mais eficiente, sem aumentar o consumo de energia não renovável.Energy conversion and balance of seven crop rotation systems for wheat were assessed from 1987 to 1995, in Passo Fundo, RS, Brazil. The following systems were evaluated: system I (wheat/soybean; system II (wheat

  7. 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.

  8. Crop residues as driver for N2O emissions from a sandy loam soil

    DEFF Research Database (Denmark)

    Pugesgaard, Siri; Petersen, Søren O.; Chirinda, Ngonidzashe

    2017-01-01

    -term experiment on a loamy sand soil at Foulum in Denmark. All cropping systems included winter wheat, a leguminous crop (faba bean or grass-clover), potato and spring barley grown in different 4-crop rotations varying in strategies for N supply (fertilizer/manure type and rate, use of catch crops and green...

  9. U.S. Effort in the Development of New Crops (Lesquerella, Pennycress, Coriander, and Cuphea)

    Science.gov (United States)

    The U.S. effort for the development of New Crops is directed toward the advancement of crops that can be grown in rotation with traditional commodity crops, off-season production and utilization of acreage not currently under cultivation. This effort is intended to have no or minimal impact on crop...

  10. Rotating preventers

    International Nuclear Information System (INIS)

    Tangedahl, M.J.; Stone, C.R.

    1992-01-01

    This paper reports that recent changes in the oil and gas industry and ongoing developments in horizontal and underbalanced drilling necessitated development of a better rotating head. A new device called the rotating blowout preventer (RBOP) was developed by Seal-Tech. It is designed to replace the conventional rotating control head on top of BOP stacks and allows drilling operations to continue even on live (underbalanced) wells. Its low wear characteristics and high working pressure (1,500 psi) allow drilling rig crews to drill safely in slightly underbalanced conditions or handle severe well control problems during the time required to actuate other BOPs in the stack. Drilling with a RBOP allows wellbores to be completely closed in tat the drill floor rather than open as with conventional BOPs

  11. 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.

  12. 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.

  13. 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.

  14. Refueling system with small diameter rotatable plugs

    International Nuclear Information System (INIS)

    Ritz, W.C.

    1987-01-01

    This patent describes a liquid-metal fastbreeder nuclear reactor comprising a reactor pressure vessel and closure head therefor, a reactor core barrel disposed within the reactor vessel and enclosing a reactor core having therein a large number of closely spaced fuel assemblies, and the reactor core barrel and the reactor core having an approximately concentric circular cross-sectional configuration with a geometric center in predetermined location within the reactor vessel. The improved refueling system described here comprises: a large controllably rotatable plug means comprising the substantial portion of the closure head, a reactor upper internals structure mounted from the large rotatable plug means. The large rotatable plug means has an approximately circular configuration which approximates the cross-sectional configuration of the reactor core barrel with a center of rotation positioned a first predetermined distance from the geometric center of the reactor core barrel so that the large rotatable plug means rotates eccentrically with respect to the reactor core barrel; a small controllably rotatable plug means affixed to the large rotatable plug means and rotatable with respect thereto. The small rotatable plug means has a center of rotation which is offset a second predetermined distance from the rotational center of the large rotatable plug means so that the small rotatable plug means rotates eccentrically with respect to the large rotatable plug means

  15. 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

    [nabo x soja x arroz (PD] apresentam, respectivamente, a maior e a menor sustentabilidade entre aqueles sistemas em que a cultura da soja participa; (c o sistema S5 [campo nativo x soja x arroz (SC] apresenta o menor índice de sustentabilidade; (d o sistema S8 [Consórcio x milho x arroz (PD] apresenta a melhor distribuição e o melhor equilíbrio entre as diversas perspectivas de sustentabilidade consideradas; (e o sistema S10 [campo nativo x milho x arroz (SC] tem pior desempenho, no que se refere à sustentabilidade entre os que incluem o milho; (f o sistema de PD confere maior sustentabilidade às sucessões de cultura.The quantitative analysis with different types of indicators is crucial in determining the sustainability of crop succession. This study aimed to appraise that in tilled plain areas. The research was carried out in Pelotas, RS, Brazil at Embrapa Clima Temperado research area. The treatments consisted of successions of winter and spring-summer crops species for five years, followed by two years of fallow and three years of rice cropping. The spring-summer crops were corn and soybean, besides rice; the winter crops were cereals, leguminous pastures, mixtures species, turnip and native grass species. Seeding was performed either by no-till (NT or conventional (CT. The experiment was planned in a split-plot randomized blocks design with three replications, where the summer crops occupied the plots, while the winter's species were allocated to the subplots. The parameters measured were transformed into index to standardize the variables, each one in relation to the better measurement behavior, and arranged in four categories of analysis: (a Agronomics indices (dry weight and grain yield; (b Environmental indicators (soil fertility; (c Energy Indicators (gain and energy efficiency; d Economic Indicators (profitability and gross value of production. Through harmonic average rates calculated for each indicator, comparisons to the crop succession were then

  16. Dedicated biomass crops can enhance biodiversity in the arable landscape.

    Science.gov (United States)

    Haughton, Alison J; Bohan, David A; Clark, Suzanne J; Mallott, Mark D; Mallott, Victoria; Sage, Rufus; Karp, Angela

    2016-11-01

    Suggestions that novel, non-food, dedicated biomass crops used to produce bioenergy may provide opportunities to diversify and reinstate biodiversity in intensively managed farmland have not yet been fully tested at the landscape scale. Using two of the largest, currently available landscape-scale biodiversity data sets from arable and biomass bioenergy crops, we take a taxonomic and functional trait approach to quantify and contrast the consequences for biodiversity indicators of adopting dedicated biomass crops on land previously cultivated under annual, rotational arable cropping. The abundance and community compositions of biodiversity indicators in fields of break and cereal crops changed when planted with the dedicated biomass crops, miscanthus and short rotation coppiced (SRC) willow. Weed biomass was consistently greater in the two dedicated biomass crops than in cereals, and invertebrate abundance was similarly consistently higher than in break crops. Using canonical variates analysis, we identified distinct plant and invertebrate taxa and trait-based communities in miscanthus and SRC willows, whereas break and cereal crops tended to form a single, composite community. Seedbanks were shown to reflect the longer term effects of crop management. Our study suggests that miscanthus and SRC willows, and the management associated with perennial cropping, would support significant amounts of biodiversity when compared with annual arable crops. We recommend the strategic planting of these perennial, dedicated biomass crops in arable farmland to increase landscape heterogeneity and enhance ecosystem function, and simultaneously work towards striking a balance between energy and food security.

  17. Biomass supply from alternative cellulosic crops and crop residues: A spatially explicit bioeconomic modeling approach

    International Nuclear Information System (INIS)

    Egbendewe-Mondzozo, Aklesso; Swinton, Scott M.; Izaurralde, César R.; Manowitz, David H.; Zhang, Xuesong

    2011-01-01

    This paper introduces a spatially-explicit bioeconomic model for the study of potential cellulosic biomass supply. For biomass crops to begin to replace current crops, farmers must earn more from them than from current crops. Using weather, topographic and soil data, the terrestrial ecosystem model, EPIC, dynamically simulates multiple cropping systems that vary by crop rotation, tillage, fertilization and residue removal rate. EPIC generates predicted crop yield and environmental outcomes over multiple watersheds. These EPIC results are used to parameterize a regional profit-maximization mathematical programming model that identifies profitable cropping system choices. The bioeconomic model is calibrated to 2007–09 crop production in a 9-county region of southwest Michigan. A simulation of biomass supply in response to rising biomass prices shows that cellulosic residues from corn stover and wheat straw begin to be supplied at minimum delivered biomass:corn grain price ratios of 0.15 and 0.18, respectively. At the mean corn price of $162.6/Mg ($4.13 per bushel) at commercial moisture content during 2007–2009, these ratios correspond to stover and straw prices of $24 and $29 per dry Mg. Perennial bioenergy crops begin to be supplied at price levels 2–3 times higher. Average biomass transport costs to the biorefinery plant range from $6 to $20/Mg compared to conventional crop production practices in the area, biomass supply from annual crop residues increased greenhouse gas emissions and reduced water quality through increased nutrient loss. By contrast, perennial cellulosic biomass crop production reduced greenhouse gas emissions and improved water quality. -- Highlights: ► A new bioeconomic model predicts biomass supply and its environmental impacts. ► The model captures the opportunity cost of switching to new cellulosic crops. ► Biomass from crop residues is supplied at lower biomass price than cellulosic crops. ► Biomass from cellulosic crops has

  18. Atributos químicos de um Cambissolo Húmico após 12 anos sob preparo convencional e semeadura direta em rotação e sucessão de culturas Chemical properties of a Humic Dystrudept after 12 years under conventional and no tillage with crop succession and rotation

    Directory of Open Access Journals (Sweden)

    Andréia Patrícia Andrade

    2012-05-01

    Full Text Available O manejo adequado do solo é uma das bases para a sustentabilidade do sistema agrícola. O objetivo do estudo foi avaliar atributos químicos de um Cambissolo Húmico Alumínico após 12 anos em dois sistemas de preparo do solo, com rotação e sucessão de culturas. O experimento foi conduzido em Lages, SC, utilizando preparo convencional (PC e semeadura direta (SD, sob rotação (r e sucessão (s de culturas. O delineamento experimental foi inteiramente casualizado com quatro repetições. As sequências de cultivo foram: feijão-pousio-milho-pousio-soja-pousio no PCr; milho-pousio no PCs; feijão-aveia-milho-nabo-soja-ervilhaca na SDr; e milho-ervilhaca na SDs. As amostras de solo foram coletadas nas camadas 0-2,5; 2,5-5; 5-10; e 10-20cm. Avaliou-se carbono orgânico total (COT, cálcio, magnésio, alumínio trocável, fósforo, potássio, nitrogênio total (NT e pH em água. A SD aumentou os teores de COT e nutrientes em comparação ao PC, especialmente na camada superficial do solo. O cultivo de milho e ervilhaca em sucessão aumentou os teores de COT e NT na camada superficial do solo em comparação com a rotação sob semeadura direta.Suitable soil management is one of the bases for sustainability in agricultural systems. The study aimed to evaluate chemical properties of a Humic Dystrudept for 12 years under two tillage systems, with crops rotation and succession. The experiment was carried out in Lages, SC, under conventional tillage (CT and no-till (NT, with rotation (r and succession (s cropping systems, using crop sequences of beans-fallow-maize-fallow-soybean in CTr; maize-fallow in CTs; beans-oats-maize-fodder radish-soybean-vetch in NTr; and maize-vetch in NTs. The experimental design was completely randomized with four replicates. The soil samples were collected in the layers 0-2.5, 2.5-5, 5-10 and 10-20cm. The variables assessed were total organic carbon (TOC, calcium, magnesium, exchangeable aluminum, phosphorus, potassium

  19. Location, location, location: Extracting location value from house prices

    OpenAIRE

    Kolbe, Jens; Schulz, Rainer; Wersing, Martin; Werwatz, Axel

    2013-01-01

    The price for a single-family house depends both on the characteristics of the building and on its location. We propose a novel semiparametric method to extract location values from house prices. After splitting house prices into building and land components, location values are estimated with adaptive weight smoothing. The adaptive estimator requires neither strong smoothness assumptions nor local symmetry. We apply the method to house transactions from Berlin, Germany. The estimated surface...

  20. Dissolved Organic Carbon and Nitrogen in Andisol for Six Crop Rotations with Different Soil Management Intensity Carbono y Nitrógeno Orgánicos Disueltos en un Andisol Sometido a Seis Rotaciones de Cultivos con Diferente Intensidad en el Manejo del Suelo

    Directory of Open Access Journals (Sweden)

    Pablo Undurraga D

    2009-09-01

    Full Text Available Soil organic matter (OM content is a quality indicator, but is an inadequate indicator in the short-term because these changes take place slowly, so dissolved organic components have emerged as an alternative. In volcanic soil subjected to different crop rotations with distinct land use intensity, dissolved organic C and N (DOC and DON were determined as well as their relationship with total C and N contents in the soil, considering the effects of crop rotation, fertilization level, and soil depth. In humid samples of Humic Haploxerands collected at four depths up to 40 cm, DOC and DON contents were determined by extraction with K2SO4 and filtered. Results indicated interaction between the studied factors, DOC fluctuated between 67.8 and 151.7 mg kg-1 with the highest value with intensive management in rotations that included corn (Zea mays L. associated with a higher fertilization. DON fluctuated between 4.62 and 37.4 mg kg-1 with the highest value in non-intensive rotations that included prairie. With respect to total C, DOC reached 0.40% with intensive management and the lowest value in non-intensive management. DON showed values between 0.13 and 0.68% with respect to total N with intensive and non-intensive management, respectively. Tillage management affected DOC and DON contents depending on the fertilization level and the depth at which it was determined, and were also affected by the crop included in the rotation, thus making these parameters good indicators to evaluate the effects of agronomic management in the short-term.El contenido de materia orgánica (OM del suelo es un indicador de su calidad, sin embargo los cambios se producen lentamente, no siendo un indicador adecuado en el corto plazo, surgiendo los componentes orgánicos disueltos como una alternativa. En un suelo volcánico sometido a diferentes rotaciones de cultivos con distinta intensidad en el uso de suelo, se determinó el C y N orgánicos disueltos (DOC y DON y su

  1. 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

  2. Crop-insurance

    NARCIS (Netherlands)

    Wijk, van der S.

    1945-01-01

    Crop insurance was fairly new in the Netherlands but there was no legal objection or limitation to particular crops. If a crop were insured, it was important that the whole area of the crop were insured. Speculative insurance seemed preferable to mutual insurance.

    Crop insurance covered all risks

  3. 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

  4. 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

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

    Science.gov (United States)

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

    2017-04-01

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

  6. 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.

  7. Library Locations

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Carnegie Library of Pittsburgh locations including address, coordinates, phone number, square footage, and standard operating hours. The map below does not display...

  8. 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

  9. Soil water and mineral nitrogen content as influenced by crop ...

    African Journals Online (AJOL)

    ) and wheat–medic rotation (McWMcW) and tillage, conventional-till (CT), minimum-till (MT), no-till (NT) and zero-till (ZT) were studied. Crop rotation did not influence soil moisture content. Soil water content in CT tended to be lower compared ...

  10. Nitrogen supply and demand in short-rotation sweetgum plantations

    Science.gov (United States)

    D. Andrew Scott; James A. Burger; Donald J. Kaczmarek; Michael B. Kane

    2004-01-01

    Intensive management is crucial for optimizing hardwood plantation success, and nitrogen (N) nutrition management is one of the most important practices in intensive management. Because management of short-rotation woody crop plantations is a mixture of row-crop agriculture and plantation forestry, we tested the usefulness of an agronomic budget modified for deciduous...

  11. Contribution of Legume Rotations to the Nitrogen Requirements of a ...

    African Journals Online (AJOL)

    Industrial fertilizers are expensive for small-scale farmers who, as alternative, rely on legume crops for providing N for a subsequent maize crop. A legume-maize rotational experiment was carried out on a Rhodic Ferralsol at Mlingano Agricultural Research Institute in Muheza, Tanga, Tanzania, to evaluate the effects of ...

  12. 6 Rotation of Maize with some Leguminous Food

    African Journals Online (AJOL)

    Administrator

    Of the various management practices, which can increase the productivity of crops, fertilizer application normally gives the highest returns (Chowdhury & Chetty, 1979). For maize production, NARP/CSIR (1998). Rotation of Maize with some Leguminous Food Crops for. Sustainable Production on the Vertisols of the Accra ...

  13. Rotation history effects on soybean plants and rhizosphere microbiome

    Science.gov (United States)

    Benefits of diversified cropping systems stem from the interactions between soil characteristics, crop growth patterns and physiology, and other organisms. In order to assist in the understanding and implementation of diversified rotation sequences, a long-term experiment was established to evaluate...

  14. Automatic crop row detection from UAV images

    DEFF Research Database (Denmark)

    Midtiby, Henrik; Rasmussen, Jesper

    are considered weeds. We have used a Sugar beet field as a case for evaluating the proposed crop detection method. The suggested image processing consists of: 1) locating vegetation regions in the image by thresholding the excess green image derived from the orig- inal image, 2) calculate the Hough transform......Images from Unmanned Aerial Vehicles can provide information about the weed distribution in fields. A direct way is to quantify the amount of vegetation present in different areas of the field. The limitation of this approach is that it includes both crops and weeds in the reported num- bers. To get...... of the segmented image 3) determine the dominating crop row direction by analysing output from the Hough transform and 4) use the found crop row direction to locate crop rows....

  15. Mitigating Groundwater Depletion in North China Plain with Cropping System that Alternate Deep and Shallow Rooted Crops

    Directory of Open Access Journals (Sweden)

    Xiao-Lin Yang

    2017-06-01

    Full Text Available In the North China Plain, groundwater tables have been dropping at unsustainable rates of 1 m per year due to irrigation of a double cropping system of winter wheat and summer maize. To reverse the trend, we examined whether alternative crop rotations could save water. Moisture contents were measured weekly at 20 cm intervals in the top 180 cm of soil as part of a 12-year field experiment with four crop rotations: sweet potato→ cotton→ sweet potato→ winter wheat-summer maize (SpCSpWS, 4-year cycle; peanuts → winter wheat-summer maize (PWS, 2-year cycle; ryegrass–cotton→ peanuts→ winter wheat-summer maize (RCPWS, 3-year cycle; and winter wheat-summer maize (WS, each year. We found that, compared to WS, the SpCSpWS annual evapotranspiration was 28% lower, PWS was 19% lower and RCPWS was 14% lower. The yield per unit of water evaporated improved for wheat within any alternative rotation compared to WS, increasing up to 19%. Average soil moisture contents at the sowing date of wheat in the SpCSpWS, PWS, and RCPWS rotations were 7, 4, and 10% higher than WS, respectively. The advantage of alternative rotations was that a deep rooted crop of winter wheat reaching down to 180 cm followed shallow rooted crops (sweet potato and peanut drawing soil moisture from 0 to 120 cm. They benefited from the sequencing and vertical complementarity of soil moisture extraction. Thus, replacing the traditional crop rotation with cropping system that involves rotating with annual shallow rooted crops is promising for reducing groundwater depletion in the North China Plain.

  16. Gene Locater

    DEFF Research Database (Denmark)

    Anwar, Muhammad Zohaib; Sehar, Anoosha; Rehman, Inayat-Ur

    2012-01-01

    software's for calculating recombination frequency is mostly limited to the range and flexibility of this type of analysis. GENE LOCATER is a fully customizable program for calculating recombination frequency, written in JAVA. Through an easy-to-use interface, GENE LOCATOR allows users a high degree...... of flexibility in calculating genetic linkage and displaying linkage group. Among other features, this software enables user to identify linkage groups with output visualized graphically. The program calculates interference and coefficient of coincidence with elevated accuracy in sample datasets. AVAILABILITY......: The database is available for free at http://www.moperandib.com....

  17. Rotação de culturas no sistema plantio direto em Tibagi (PR: I - Sequestro de carbono no solo Crop rotation under no-tillage in Tibagi (Paraná State, Brazil: I - Soil carbon sequestration

    Directory of Open Access Journals (Sweden)

    Marcos Siqueira Neto

    2009-08-01

    Full Text Available Os manejos conservacionistas, como o sistema plantio direto (SPD, podem ser considerados uma atividade com potencial para sequestrar C no solo. Os objetivos deste trabalho foram quantificar os estoques de C no solo e, juntamente com a dedução das emissões de óxido nitroso (N2O, calcular o sequestro de C do solo sob SPD com diferentes tempos de implantação em duas sucessões de culturas. O experimento foi instalado na Fazenda Santa Branca, em Tibagi (PR, em um Latossolo Vermelho distroférrico de textura argilosa. Os tratamentos, dispostos em faixas não casualizadas com parcelas subdivididas, foram: plantio direto por 12 anos com sucessões milho/trigo e soja/trigo (PD12 M/T e PD12 S/T, respectivamente e por 22 anos (PD22 M/T e PD22 S/T, respectivamente. Os estoques de C no solo aumentaram com o tempo de implantação do SPD; o incremento no C do solo em 10 anos foi de 35 %, com uma taxa anual de acúmulo de 1,94 t ha-1 ano-1 . A simulação do estoque de C do solo com o uso do modelo unicompartimental mostrou que o elevado aporte de resíduos culturais e a rotação de culturas com uso de leguminosas reduziram a mineralização da matéria orgânica, o que favoreceu o acúmulo de C no solo. As emissões de N2O foram 25 % mais elevadas na sucessão milho/trigo, em relação à soja/trigo, e os diferentes tempos de SPD não promoveram aumento das emissões do N2O. O balanço entre a taxa de acúmulo de C e a emissão de óxido nitroso mostrou que o sistema apresentou saldo positivo no acúmulo de C no solo, o que significou o sequestro de CO2 de 6 t ha-1 ano-1 .Conservationist soil management systems such as no-tillage (NT can be considered activities with potential to increase soil carbon sequestration. The objective of this study was to quantify the soil C stocks and, along estimations of the nitrous oxide (N2O emissions, calculate the soil C sequestration under NT for different times of implantation in two crop successions. The

  18. Sorghum - An alternative energy crop for marginal lands and reclamation sites

    Science.gov (United States)

    Lukas, Stefan; Theiß, Markus; Jäkel, Kerstin

    2017-04-01

    The production of biogas and the associated cultivation of energy crops are still of great importance. Considering increasing restrictions for the cultivation of standard biogas crop maize regarding an environmentally friendly production of biomass, a wider range of energy crops is needed. The cultivation of sorghum can contribute to this. As maize, sorghum is a C4-plant and offers a high biomass yield potential. Originated in the semi-arid tropics, sorghum is well adapted to warm and dry climate and particularly noted for its drought tolerance compared to maize. It also makes few demands on soil quality and shows a good capability of nutrient acquisition. Therefore, particularly on marginal areas and reclamation sites with low soil nutrient and water content sorghum can contribute to secure crop yield and income of farmers. The applied research project aims at and reflects on the establishment of sorghum as a profitable and ecological friendly cropping alternative to maize, especially in the face of probable climate change with increasing risks for agriculture. For this purpose, site differentiated growing and cultivar trials with a standardized planting design as well as several practical on-farm field experiments were conducted. The agronomical and economic results will lead to scientifically based procedures and standards for agricultural practice with respect to cultivation methods (drilling, pest-management, fertilization), cropping sequence and technique, cropping period or position in crop rotation. Even by now there is a promising feedback from the agricultural practice linked with an increasing demand for information. Moreover, the specific cropping area is increasing continuously. Therefore, the leading signs for the establishment of sorghum as profitable alternative to maize biogas production are positive. Sorghum cultures perform best as main crops in the warm D locations in the middle and East German dry areas. Here, the contribution margin

  19. Interaction Between Livestock And Crop Farming In Northern Nigeria

    African Journals Online (AJOL)

    The study looked at the role of livestock and its interaction with crop production in an integrated crop-livestock farming system in Katsina State. Field data were collected through household survey of 120 respondent located in six villages in Katsina State. The result shows that there was a high level of crop-livestock ...

  20. Long-term effects of conservation systems on productivity for the old rotation

    Science.gov (United States)

    Winter legumes in cotton (Gossypium hirsutum L.) production is not new to the Southeast. In 1896, the Old Rotation experiment at Auburn University was established to study the feasibility of producing cotton in crop rotations with winter legumes managed as a green manure crop. Throughout the experim...

  1. Rotational scanography

    International Nuclear Information System (INIS)

    Moore, R.; Amplatz, K.

    1981-01-01

    With rotational scanography contrast and resolution of X-ray images are improved. The technique bases on the principle of a narrow X-ray passing along an object, thus exposing the whole film. The X-ray is limited by a primary shield next to the X-ray tube. A second shield between object and film prevents that scattered rays spoil the film. The X-ray tube is turned around a horizontal axis, whilst the shield is shifted so that the irradiation intensity remains constant and the smallest projected focal size is obtained. This technique permits to enlarge the X-ray images by 3 or 6 times its size. Thus, films up to a length of 96 cm can be exposed. Main advantages of rotary scanography are reduced exposure to radiation of patient and applicant, improved contrast and resolution of the X-ray image, and a larger play of exposure for the X-ray technique. Disadvantages are a longer exposure time and the consequently increased demands on X-ray generator and treatment head. When a multi-slit shield is used, the patient must be cooperative in order to prevent movement artifacts. This imaging technique is highly sensitive to artifacts, particularly if the tube voltage provides large fluctuations. Supplementary units are necessary. The significance of the rotational scanography is that it permits the reduction of the radiation dose, whilst contrast and resolution of the images are improved. This can be illustrated by X-ray images of a CT-phantom and of pelvic, hand and gastrointenstinal phantoms. (orig./MG) [de

  2. Nitrogen effects on maize yield following groundnut in rotation on ...

    African Journals Online (AJOL)

    Rotating maize (Zea mays L.) with groundnut (Arachis hypogaea L.) has been proposed as a way to maintain soil fertility and prevent maize productivity declines in the smallholder cropping systems of sub-humid Zimbabwe. Field experiments with fertilizer-N on maize in rotation with groundnut were conducted at three ...

  3. African Crop Science Journal

    African Journals Online (AJOL)

    The African Crop Science Journal, a quarterly publication, publishes original research papers dealing with all aspects of crop agronomy, production, genetics and breeding, germplasm, crop protection, post harvest systems and utilisation, agro-forestry, crop-animal interactions, information science, environmental science ...

  4. 7 CFR 205.203 - Soil fertility and crop nutrient management practice standard.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Soil fertility and crop nutrient management practice... Requirements § 205.203 Soil fertility and crop nutrient management practice standard. (a) The producer must... nutrients and soil fertility through rotations, cover crops, and the application of plant and animal...

  5. Evaluation of Cowpea Germplasm Lines Adapted for Use as a Cover Crop in the Southeastern US

    Science.gov (United States)

    Cowpeas (Vigna unguiculata) are desirable as a cover crop, because they are tolerant of heat, drought and poor soils, grow vigorously and compete well against weeds, and provide nitrogen for rotational crops. Cowpeas were grown extensively as a forage and green manure crop in the southeastern U.S. ...

  6. Danish farmer’s perception of GM-crops

    DEFF Research Database (Denmark)

    Søndergaard, Janus; Pedersen, Søren Marcus; Gylling, Morten

    2005-01-01

    This paper presents a study of 185 farmer’s perception of GM-crops in Denmark. The respondent’s attitude to GM-crops mainly reflects a conservative view of the adoption of GM-crops. Among farmers only the exciting crops in rotation is seen as their future potential GM-crops. Findings from...... this study show that more the 60 pct do not expect any or less than 13 EUR increase in gross margins on their farms from adopting GM-crops. This assessment illustrates that the farmers regard the GM-crops more as a way of ‘staying in business” than a technology to increase their profits....

  7. Impact of cash cropping and perennial crops on food crop ...

    African Journals Online (AJOL)

    than labor; E is exogenous income We assume households can sell parts or all of food crop, PCC and ... Farmers may also get informal credit from village money lenders based on their credit worthiness, which ..... exogenous at the time of making food crop planting decisions as the latter are annual and the former (PCC and ...

  8. Snakes and spin rotators

    International Nuclear Information System (INIS)

    Lee, S.Y.

    1990-01-01

    The generalized snake configuration offers advantages of either shorter total snake length and smaller orbit displacement in the compact configuration or the multi-functions in the split configuration. We found that the compact configuration can save about 10% of the total length of a snake. On other hand, the spilt snake configuration can be used both as a snake and as a spin rotator for the helicity state. Using the orbit compensation dipoles, the spilt snake configuration can be located at any distance on both sides of the interaction point of a collider provided that there is no net dipole rotation between two halves of the snake. The generalized configuration is then applied to the partial snake excitation. Simple formula have been obtained to understand the behavior of the partial snake. Similar principle can also be applied to the spin rotators. We also estimate the possible snake imperfections are due to various construction errors of the dipole magnets. Accuracy of field error of better than 10 -4 will be significant. 2 refs., 5 figs

  9. 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.

  10. Impact of catch crop mixtures and soils on microbial diversity and nitrogen cycling communities in agroecosystems

    Science.gov (United States)

    Burbano, Claudia S.; Große, Julia; Hurek, Thomas; Reinhold-Hurek, Barbara

    2017-04-01

    In light of the projected world's population growth, food supplies will necessary have to increase. Soils are an essential component for achieving this expansion and its quality and fertility are crucial for bio-economic productivity. Catch crops can be an option to preserve or even improve soil productivity because of their effect on soil fertility and health. A long-term field experiment of the CATCHY project (Catch-cropping as an agrarian tool for continuing soil health and yield-increase) with two contrasting crop rotations was established in two different locations in Northern and Southern Germany. Single catch crops (white mustard, Egyptian clover, phacelia and bristle oat), catch crop mixtures (a mixture of the above and a commercial mixture) and main crops (wheat and maize) have been grown. To investigate how catch crops can affect the microbial diversity and particularly the microbial nitrogen cycling communities, we are studying first the short-term effect of different catch crop mixtures on the microbiomes associated with soils and roots. We compared these microbiomes with wheat plants, representing the microbial community before a catch crop treatment. Roots, rhizosphere and bulk soils were collected from representative samples of wheat plants from one field. The same compartments were also sampled from one fallow treatment and three catch crops variants from three fields each. The variants consisted of white mustard and the two catch crop mixtures. All fields were sampled by triplicate. Quantitative analyses were carried out by qPCR based on key functional marker genes for mineralization (ureC), nitrification (amoA), dissimilatory nitrate and nitrite reduction to ammonium -DNRA- (nrfA), denitrification (nirK, nirS, nosZ), and nitrogen fixation (nifH). These genes were targeted at the DNA and RNA level for the characterization of the microbial population and the actual transcription activity, respectively. We detected the presence and activity of

  11. 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

  12. Comparison of the Stereotactic Accuracies of Function-Guided Deep Brain Stimulation, Calculated Using Multitrack Target Locations Geometrically Inferred from Three-Dimensional Trajectory Rotations, and of Magnetic Resonance Imaging-Guided Deep Brain Stimulation and Outcomes.

    Science.gov (United States)

    Park, Seong-Cheol; Lee, Chong Sik; Kim, Seok Min; Choi, Eu Jene; Lee, Jung Kyo

    2017-02-01

    In previous studies, multitrack trajectories in deep brain stimulation (DBS) have usually been approximated. Using a geometrically more accurate method, we compared the stereotactic accuracy of DBS with multitrack microelectrode recording and awake stimulation (function group) and MRI-guided DBS (MRI group). One hundred and seventy-two leads used in DBS between April 2014 and January 2016 were evaluated for stereotactic errors. Targets were the subthalamic nucleus (STN, 139 leads) or globus pallidus interna (GPi, 33 leads). We geometrically calculated shifted-track targets by considering the three-dimensional stereotactic ring and arc rotations. Stereotactic errors were calculated using Euclidean distances perpendicular to trajectories. Motor outcomes according to the Unified Parkinson's Disease Rating Scale (UPDRS) part III, improvement percentages by stimulations, were analyzed in 24 patients with 1 year follow-ups. Functional evaluation tended to increase stereotactic errors in the STN function group (n = 129; 1.4 ± 0.7 mm) more than in the STN MRI group (n = 10; 1.0 ± 0.6 mm; P = 0.06). Leads with higher stereotactic errors (n = 65; 1.6 ± 0.7 mm; P 2.5 mm tended to relate to a worse outcome (P = 0.087). Stereotactic errors were lower (n = 33; 0.9 ± 0.5 mm) in the GPi MRI group. Multitrack DBS using intraoperative functional evaluation resulted in worse stereotactic accuracy than did MRI-guided DBS. However, track shifts in function-guided DBS can approach MRI targets effectively. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Residue-specific membrane location of peptides and proteins using specifically and extensively deuterated lipids and {sup 13}C-{sup 2}H rotational-echo double-resonance solid-state NMR

    Energy Technology Data Exchange (ETDEWEB)

    Xie Li; Ghosh, Ujjayini; Schmick, Scott D.; Weliky, David P., E-mail: weliky@chemistry.msu.edu [Michigan State University, Department of Chemistry (United States)

    2013-01-15

    Residue-specific location of peptides in the hydrophobic core of membranes was examined using {sup 13}C-{sup 2}H REDOR and samples in which the lipids were selectively deuterated. The transmembrane topology of the KALP peptide was validated with this approach with substantial dephasing observed for deuteration in the bilayer center and reduced or no dephasing for deuteration closer to the headgroups. Insertion of {beta} sheet HIV and helical and {beta} sheet influenza virus fusion peptides into the hydrophobic core of the membrane was validated in samples with extensively deuterated lipids.

  14. Crop residues quantification to obtain self-consumption compost in an organic garden

    Science.gov (United States)

    Lopez de Fuentes, Pilar; Lopez Merino, María; Remedios Alvir, María; Briz de Felipe, Teresa

    2013-04-01

    This research focuses on quantifying the crop residue left after the campaign fall/winter (2011) for the organic garden crops of Agricultural ETSI, located in practice fields, to get compost for self-generated residues arising from within their own fields. This compost is produced by mixing this material with an organic residues source animal. In this way the plant organic residues provided the nitrogen required for an appropriate C/N and the animal organic residues can provide the carbon amount required to achieve an optimal scenario. The garden has a surface area of 180 m2 which was cultured with different seasonal vegetables, different families and attending practices and species associations' rotations, proper of farming techniques. The organic material of animal origin referred to, is rest from sheep renew bed, sustained management support the precepts of organic farming and cottage belongs to practice fields too. At the end of crop cycle, we proceeded to the harvest and sorting of usable crop residues, which was considered as net crop residues. In each case, these residues were subjected to a cutting treatment by the action of a mincing machine and then weighed to estimate the amounts given by each crop. For the sheep bed residue 1m2 was collected after three months having renewed. It had been made by providing 84 kg of straw bales in July and introducing about 12 Kg each. The herd consisted of three females and one playe. Each one of them was feed 300g and 600 g of straw per day. Two alternating different pens were used to simulate a regime of semi-intensive housing. A balance on how much organic residue material was obtained at the end and how much was obtained in the compost process is discussed in terms of volume and nutrients content is discussed.

  15. Propriedades físicas do solo sob preparo convencional e semeadura direta em rotação e sucessão de culturas, comparadas às do campo nativo Physical soil properties of conventional tillage and no-tillage, in crop rotation and succession, compared with natural pasture

    Directory of Open Access Journals (Sweden)

    I. Bertol

    2004-02-01

    sustentabilidade da semeadura direta no que se refere à estabilidade dos agregados em água. Os sistemas de cultivo não influenciaram as propriedades físicas do solo.In soils with naturally favorable characteristics for cultivation, conventional tillage degrades the physical soil properties, since this management system causes the rupture of aggregates, soil compaction, and eliminates soil cover. No-tillage, on the other hand, maintains soil cover and improves physical properties, but consolidates the surface layer. Our study was conducted on a Haplumbrept soil, from May 1995 to April 2001. Five soil tillage treatments were used: conventional tillage crop rotation (CTR, conventional tillage crop succession (CTS, no-tillage crop rotation (NTR, no-tillage crop succession (NTS, and natural pasture (NP, in four replications each. The crop sequences were bean/fallow/maize/fallow/soybean/fallow in CTR, maize/fallow/maize/fallow/maize/fallow in CTS, bean/oat/maize/turnip/soybean/vetch in NTR and maize/vetch/maize/vetch/maize/vetch in NTS. Soil density, macroporosity, microporosity, total porosity, organic carbon, and water aggregate stability (MWD were evaluated in April 2001 for the soil layers 0-2.5, 2.5-5, 5-10, 10-15, 15-20, and 20-30 cm. In the 0-10 cm layer, soil density was higher in no-tillage than conventional tillage and natural pasture, while macroporosity, total porosity, and the macroporosity/total porosity relation was higher in conventional tillage in the mean for cropping systems, in this layer. Organic carbon, MWD, and sensibility index for MWD means of layers and tillage systems were higher in no-tillage and natural pasture than in conventional tillage.

  16. Rotating Cavitation Supression Project

    Data.gov (United States)

    National Aeronautics and Space Administration — FTT proposes development of a rotating cavitation (RC) suppressor for liquid rocket engine turbopump inducers. Cavitation instabilities, such as rotating cavitation,...

  17. 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.......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....

  18. Rotação de culturas no sistema plantio direto em Tibagi (PR: II - Emissões de CO2 e N2O Crop rotation under no-tillage in Tibagi (Paraná State, Brazil: II - CO2 and N2O emissions

    Directory of Open Access Journals (Sweden)

    Marcos Siqueira Neto

    2009-08-01

    Full Text Available A atividade agrícola pode alterar a quantidade e qualidade da matéria orgânica do solo (MOS, resultando em emissões de dióxido de carbono (CO2 e óxido nitroso (N2O do solo para a atmosfera. O sistema plantio direto (SPD com a utilização de leguminosas em sistemas de rotação é uma estratégia que deve ser considerada tanto para o aumento da quantidade de MOS como para seu efeito na redução das emissões dos gases de efeito estufa. Com o objetivo de determinar os fluxos de gases do efeito estufa (CO2 e N2O do solo, um experimento foi instalado em Tibagi (PR, em um Latossolo Vermelho distroférrico textura argilosa. Os tratamentos, dispostos em faixas não casualizadas com parcelas subdivididas, foram: sistema plantio direto por 12 anos com sucessões milho/trigo e soja/trigo (PD12 M/T e PD12 S/T, respectivamente e por 22 anos (PD22 M/T e PD22 S/T, respectivamente. As emissões de CO2 do solo foram aproximadamente 20 % mais elevadas no PD22 em relação ao PD12. As emissões de CO2 apresentaram correlação significativa (R² = 0,85; p The agricultural activity can change the quantity and quality of soil organic matter (SOM, resulting in CO2 and N2O emissions from the soil. No-tillage (NT with legume species in crop rotation is a strategy that should be considered not only to increase the SOM quantity, but also to reduce greenhouse gas emissions. The objective of this study was to determine the soil-atmosphere gas emissions with greenhouse effect (CO2 and N2O. For this purpose, an experiment was installed in Tibagi (Paraná State, Brazil, on a clayey Oxisol (Typic Hapludox. The treatments were conducted in non-random strips with subdivided plots: no-tillage crop successions corn/wheat and soybean/wheat (NT12 M/T and NT12 S/T, respectively for 12 years and no-tillage (NT22 M/T and NT22 S/T, respectively for 22 years. The CO2 soil emissions were nearly 20 % higher in NT22 than in NT12. The CO2 emissions were significantly correlated (R

  19. Sorghums as energy crops

    Energy Technology Data Exchange (ETDEWEB)

    Lipinsky, E. S.; Kresovich, S.

    1980-01-01

    The botanical, physiological, and agronomic characteristics of sorghum are described. Integration concepts to improve sorghum prospects are discussed as follows: multiple sweet sorghum crops each year, integration with sugarcane, integration with sugar beets, integration with starch crops, sweet stemmed grain sorghum, and integration with lignocellulosic crops. (MHR)

  20. Does agricultural crop diversity enhance soil microbial biomass and organic matter dynamics? A meta-analysis.

    Science.gov (United States)

    McDaniel, M D; Tiemann, L K; Grandy, A S

    2014-04-01

    Our increasing dependence on a small number of agricultural crops, such as corn, is leading to reductions in agricultural biodiversity. Reductions in the number of crops in rotation or the replacement of rotations by monocultures are responsible for this loss of biodiversity. The belowground implications of simplifying agricultural plant communities remain unresolved; however, agroecosystem sustainability will be severely compromised if reductions in biodiversity reduce soil C and N concentrations, alter microbial communities, and degrade soil ecosystem functions as reported in natural communities. We conducted a meta-analysis of 122 studies to examine crop rotation effects on total soil C and N concentrations, and the faster cycling microbial biomass C and N pools that play key roles in soil nutrient cycling and physical processes such as aggregate formation. We specifically examined how rotation crop type and management practices influence C and N dynamics in different climates and soil types. We found that adding one or more crops in rotation to a monoculture increased total soil C by 3.6% and total N by 5.3%, but when rotations included a cover crop (i.e., crops that are not harvested but produced to enrich the soil and capture inorganic N), total C increased by 8.5% and total N 12.8%. Rotations substantially increased the soil microbial biomass C (20.7%) and N (26.1%) pools, and these overwhelming effects on microbial biomass were not moderated by crop type or management practices. Crop rotations, especially those that include cover crops, sustain soil quality and productivity by enhancing soil C, N, and microbial biomass, making them a cornerstone for sustainable agroecosystems.

  1. [Mechanism on biodiversity managing crop diseases].

    Science.gov (United States)

    Yang, Jing; Shi, Zhu-Feng; Gao, Dong; Liu, Lin; Zhu, You-Yong; Li, Cheng-Yun

    2012-11-01

    Reasonable utilization of natural resource and protection of ecological environment is the foundation for implementing agricultural sustainable development. Biodiversity research and protection are becoming an important issue concerned commonly in the world. Crop disease is one of the important natural disasters for food production and safety, and is also one of the main reasons that confine sustainable development of agricultural production. Large-scale deployment of single highly resistant variety results in reduction of agro-biodiversity level. In this case, excessive loss of agro-biodiversity has become the main challenge in sustainable agriculture. Biodiversity can not only effectively alleviate disease incidence and loss of crop production, but also reduce pollution of agricultural ecological environment caused by excessive application of pesticides and fertilizers to the agricultural ecological environment. Discovery of the mechanism of biodiversity to control crop diseases can reasonably guide the rational deployment and rotation of different crops and establish optimization combinations of different crops. This review summarizes recent advances of research on molecular, physiological, and ecological mechanisms of biodiversity managing crop diseases, and proposes some research that needs to be strengthened in the future.

  2. Leaf wetness distribution within a potato crop

    Science.gov (United States)

    Heusinkveld, B. G.

    2010-07-01

    The Netherlands has a mild maritime climate and therefore the major interest in leaf wetness is associated with foliar plant diseases. During moist micrometeorological conditions (i.e. dew, fog, rain), foliar fungal diseases may develop quickly and thereby destroy a crop quickly. Potato crop monocultures covering several hectares are especially vulnerable to such diseases. Therefore understanding and predicting leaf wetness in potato crops is crucial in crop disease control strategies. A field experiment was carried out in a large homogeneous potato crop in the Netherlands during the growing season of 2008. Two innovative sensor networks were installed as a 3 by 3 grid at 3 heights covering an area of about 2 hectares within two larger potato crops. One crop was located on a sandy soil and one crop on a sandy peat soil. In most cases leaf wetting starts in the top layer and then progresses downward. Leaf drying takes place in the same order after sunrise. A canopy dew simulation model was applied to simulate spatial leaf wetness distribution. The dew model is based on an energy balance model. The model can be run using information on the above-canopy wind speed, air temperature, humidity, net radiation and within canopy air temperature, humidity and soil moisture content and temperature conditions. Rainfall was accounted for by applying an interception model. The results of the dew model agreed well with the leaf wetness sensors if all local conditions were considered. The measurements show that the spatial correlation of leaf wetness decreases downward.

  3. Assessments of carbon and water cycling in multiple agricultural ecosystems in the Inland Pacific Northwest using eddy covariance flux measurements and integrated basin-crop model simulation

    Science.gov (United States)

    Chi, J.; Maureira, F.; Waldo, S.; O'Keeffe, P.; Pressley, S. N.; Stockle, C. O.; Lamb, B. K.

    2014-12-01

    Local meteorology, crop management practices and site characteristics have important impacts on carbon and water cycling in agricultural ecosystems. This study focuses on carbon and water fluxes measured using eddy covariance (EC) methods and crop simulation models in the Inland Pacific Northwest (IPNW), in association with the Regional Approaches to Climate Change (REACCH) program. The agricultural ecosystem is currently challenged by higher pressure on water resources as a consequence of population growth and increasing exposure to impacts associated with different types of crop managements. In addition, future climate projections for this region show a likely increase in temperature and significant reductions in precipitation that will affect carbon and water dynamics. This new scenario requires an understanding of crop management by assessing efficient ways to face the impacts of climate change at the micrometeorological level, especially in regards to carbon and water flow. We focus on three different crop management sites. One site (LIND) under crop-fallow is situated in a low-rainfall area. The other two sites, one no-till site (CAF-NT) and one conventional tillage site (CAF-CT), are located in an area of high-rainfall with continuous cropping. In this study, we used CropSyst micro-basin model to simulate the responses in carbon and water budgets at each site. Based on the EC processed results for net ecosystem exchange (NEE) of CO2, the CAF-NT site was a carbon sink during 2013 when spring garbanzo was planted; while the paired CAF-CT site, under similar crop rotation and meteorological conditions, was a carbon source during the same period. The LIND site was also a carbon sink where winter wheat was growing during 2013. Model results for CAF-NT showed good agreement with the EC carbon and water flux measurements during 2013. Through comparisons between measurements and modeling results, both short and long term processes that influence carbon and water

  4. Soil salinization and maize and cowpea yield in the crop rotation system using saline waters Salinização do solo e produtividade de milho e feijão caupi em sistema de rotação cultural utilizando águas salinas

    Directory of Open Access Journals (Sweden)

    Claudivan F. Lacerda

    2011-01-01

    Full Text Available The use of saline water and the reuse of drainage water for irrigation depend on long-term strategies that ensure the sustainability of socio-economic and environmental impacts of agricultural systems. In this study, it was evaluated the effects of irrigation with saline water in the dry season and fresh water in the rainy season on the soil salt accumulation yield of maize and cowpea, in a crop rotation system. The experiment was conducted in the field, using a randomized complete block design, with five replications. The first crop was installed during the dry season of 2007, with maize irrigated with water of different salinities (0.8, 2.2, 3.6 and 5.0 dS m-1. The maize plants were harvested at 90 days after sowing (DAS, and vegetative growth, dry mass of 1000 seeds and grain yield were evaluated. The same plots were utilized for the cultivation of cowpea, during the rainy season of 2008. At the end of the crop, cycle plants of this species were harvested, being evaluated the vegetative growth and plant yield. Soil samples were collected before and after maize and cowpea cultivation. The salinity of irrigation water above 2.2 dS m-1 reduced the yield of maize during the dry season. The high total rainfall during the rainy season resulted in leaching of salts accumulated during cultivation in the dry season, and eliminated the possible negative effects of salinity on cowpea plants. However, this crop showed atypical behavior with a significant proportion of vegetative mass and low pod production, which reduced the efficiency of this strategy of crop rotation under the conditions of this study.A utilização de águas salinas bem como o reúso de águas de drenagem na irrigação dependem de estratégias de longo prazo que garantam a sustentabilidade socioeconômica e ambiental dos sistemas agrícolas. Neste trabalho, avaliaram-se os efeitos da irrigação com água salina na estação seca e com água de baixa salinidade na estação chuvosa

  5. Effect of crop sequence and crop residues on soil C, soil N and yield of maize

    International Nuclear Information System (INIS)

    Shafi, M.; Bakht, J.; Attaullah; Khan, M.A.

    2010-01-01

    Improved management of nitrogen (N) in low N soils is critical for increased soil productivity and crop sustainability. The objective of the present study was to evaluate the effects of residues incorporation, residues retention on soil surface as mulch, fertilizer N and legumes in crop rotation on soil fertility and yield of maize (Zea may L.). Fertilizer N was applied to maize at the rate of 160 kg ha/sup -1/, and to wheat at the rate of 120 kg ha/sup -1/ or no fertilizer N application. Crop rotation with the sequence of maize after wheat (Triticum aestivum L.), maize after lentil (Lens culinaris Medic) or wheat after mash bean (Vigna mungo L.) arranged in a split plot design was followed. Post-harvest incorporation of crop residues and residues retention on soil surface as mulch had significantly (p=0.05) affected grain and stover yield during 2004 and 2005. Two years average data revealed that grain yield was increased by 3.31 and 6.72% due to mulch and residues incorporation. Similarly, stover yield was also enhanced by 5.39 and 10.27% due to the same treatment respectively. Mulch and residues incorporation also improved stover N uptake by 2.23 and 6.58%, respectively. Total soil N and organic matter was non significantly (p=0.05) increased by 5.63 and 2.38% due to mulch and 4.13, 7.75% because of crop residues incorporation in the soil. Maize grain and stover yield responded significantly (p=0.05) to the previous legume (lentil) crop when compared with the previous cereal crop (wheat). The treatment of lentil - maize(+N), on the average, increased grain yield of maize by 15.35%, stover yield by 16.84%, total soil N by 10.31% and organic matter by 10.17%. Similarly, fertilizer N applied to the previous wheat showed carry over effect on grain yield (6.82%) and stover yield (11.37%) of the following maize crop. The present study suggested that retention of residues on soil surface as mulch, incorporation of residues in soil and legume (lentil - maize) rotation

  6. Energy crops for biogas plants. Thuringia; Energiepflanzen fuer Biogasanlagen. Thueringen

    Energy Technology Data Exchange (ETDEWEB)

    Biertuempfel, A.; Bischof, R.; Conrad, M. (and others)

    2012-06-15

    In the brochure under consideration the Agency for Renewable Resources (Guelzow-Pruezen, Federal Republic of Germany) reports on the support of the implementation of different plant cultures in structure of plantations and crop rotation systems of companies under consideration of the Federal State Thuringia. The main chapters of this brochure are: Crops for the production of biogas; implementation in plantations; ensilage and biogas yields; economy of the cultivation of energy plants.

  7. Energy crops for biogas plants. Saxony; Energiepflanzen fuer Biogasanlagen. Sachsen

    Energy Technology Data Exchange (ETDEWEB)

    Biertuempfel, A.; Buttlar, C. von; Conrad, M. [and others

    2012-08-15

    In the brochure under consideration the Agency for Renewable Resources (Guelzow-Pruezen, Federal Republic of Germany) reports on the support of the implementation of different plant cultures in structure of plantations and crop rotation systems of companies under consideration of the Federal State Saxony. The main chapters of this brochure are: Crops for the production of biogas; implementation in plantations; ensilage and biogas yields; economy of the cultivation of energy plants.

  8. Economic assessment and comparison of acacia energy crop with annual traditional crops in Southern Europe

    International Nuclear Information System (INIS)

    Gasol, Carles M.; Rieradevall, Joan; Gabarrell, Xavier; Brun, Filippo; Mosso, Angela

    2010-01-01

    In several policy documents bioenergy is recognized as an important renewable energy source in Italy. The increase in energy prices represents an opportunity for lignocellulosic energy crops such as acacia and poplar. However, for Short Rotation Coppice (SRC) and Short Rotation Forestry (SRF) to be adopted by farmers, these crops must be perceived to be at least as profitable as crops that normally compete with these plantations for land use. The purpose of this paper is to evaluate the economic feasibility of acacia (Robinia pseudoacacia) as an energy crop in a low input production regime in Italy and, in particular, to consider its competitiveness with wheat. Our results show that neither SRC and SRF techniques using assumed production costs (EUR3820 and EUR5285 ha -1 yr -1 ) nor biomass productions are able to obtain a positive profit (-EUR184 and -EUR172 ha -1 yr -1 ) that can convince farmers to invest in biomass plantations on their land. The results demonstrate that wheat is a more economically secure option than SRC or SRF. The viability of local biomass production in Italy and Southern Europe depends on the active support of the governments; without them, biomass is not economically competitive for the farmers when compared to crops such as wheat. (author)

  9. 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.

  10. Improvement of red pepper yield and soil environment by summer catch aquatic crops in greenhouses

    Science.gov (United States)

    Du, X. F.; Wang, L. Z.; Peng, J.; Wang, G. L.; Guo, X. S.; Wen, T. G.; Gu, D. L.; Wang, W. Z.; Wu, C. W.

    2016-08-01

    To investigate effects of the rotation of summer catch crops on remediation retrogressed soils in continuous cropping, a field experiment was conducted. Rice, water spinach, or cress were selected as summer catch crops; bare fallow during summer fallow was used as the control group. Results showed that aquatic crops grown in summer fallow period could effectively reduce soil bulk density and pH, facilitate soil nutrient release, and improve soil physical and chemical properties compared with those grown in fallow period. Paddy-upland rotation could improve soil microbial members and increase bacterial and actinomycete populations; by contrast, paddy-upland rotation could reduce fungal populations and enhance bacterium-to-fungus ratio. Paddy-upland rotation could also actively promote activities of soil enzymes, such as urease, phosphatase, invertase, and catalase. The proposed paddy-upland rotation significantly affected the growth of red pepper; the yield and quality of the grown red pepper were enhanced. Summer catch crops, such as rice, water spinach, and cress significantly increased pepper yield in the following growing season by 15.4%, 10.2% and 14.0%, respectively, compared with those grown in fallow treatment. Therefore, the proposed paddy-upland crop rotation could be a useful method to alleviate continuous cropping problems involved in cultivating red pepper in greenhouses.

  11. Grass plants crop water consumption model in urban parks located ...

    African Journals Online (AJOL)

    The most important issue is the to use of urban space to increase the number and size of green areas. As well as another important issue is to work towards maintaining these spaces. One such important effort is to meet the water needs of plants. Naturally, the amount of water needed by plants depends on the species.

  12. Earthworm populations are affected from Long-Term Crop Sequences and Bio-Covers under No-Tillage

    Science.gov (United States)

    Earthworms are crucial for improving soil biophysical properties in cropping systems. Consequently, effects of cropping rotation and bio-covers were assessed on earthworm populations under no-tillage sites. Main effects of 6 different cropping sequences [corn (Zea mays), cotton (Gossypium hirsutum),...

  13. Harvesting short rotation woody crops with a shear

    Science.gov (United States)

    Wellington Cardoso; Dana Mitchell; Tom Gallagher; Daniel. and de Souza

    2014-01-01

    A time and motion study was performed on a skid steer equipped with a 14-inch tree shear attachment. The machine was used to install initial coppice harvesting treatments on three stands across the south. The study included one willow and two cottonwood sites. The stands averaged from 2 to 4 years old. Approximately 200 trees were shear harvested from each of the...

  14. Short rotation woody crops program: 1982 program summary

    Energy Technology Data Exchange (ETDEWEB)

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

    1982-09-01

    The general objective and overall approach of the program are discussed, and the status, specific goals, and recent results of the three major research areas are presented. The report concludes with brief summaries of the individual research projects in the program.

  15. Rotation of Maize with some Leguminous Food Crops for ...

    African Journals Online (AJOL)

    GMX 92–16-2M), bambara groundnut (Vigna subterranea (L.) Verd, var. Ada) and groundnut (Arachis hypogea L., var. goronga). The experimental treatments were: incorporated legume residues, recommended inorganic fertilizer application (100 kg N, 60 kg P O and 40 kg K SO ha-1) and no fertilization as 2 5 2 4 control.

  16. 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 ...

  17. Nitrate Leaching, Yields and Carbon Sequestration after Noninversion Tillage, Catch Crops, and Straw Retention

    DEFF Research Database (Denmark)

    Hansen, Elly Møller; Munkholm, Lars Juhl; Olesen, Jørgen E

    2015-01-01

    Crop management factors, such as tillage, rotation, and straw retention, need to be long-term to allow conclusions on effects on crop yields, nitrate leaching, and carbon sequestration. In 2002, two field experiments, each including four cash crop rotations, were established on soils with 9 and 15......% clay, under temperate, coastal climate conditions. Direct drilling and harrowing to two different depths were compared to plowing with respect to yield, nitrate N leaching, and carbon sequestration. For comparison of yields across rotations, grain and seed dry matter yields for each crop were converted...... fodder radish due to the efficient catch crop. Soil organic carbon (SOC) did not increase significantly after 7 yr of straw incorporation or noninversion tillage. There was no correlation between N balances calculated for each growing season and N leaching measured in the following percolation period....

  18. Glyphosate sustainability in South American cropping systems.

    Science.gov (United States)

    Christoffoleti, Pedro J; Galli, Antonio J B; Carvalho, Saul J P; Moreira, Murilo S; Nicolai, Marcelo; Foloni, Luiz L; Martins, Bianca A B; Ribeiro, Daniela N

    2008-04-01

    South America represents about 12% of the global land area, and Brazil roughly corresponds to 47% of that. The major sustainable agricultural system in South America is based on a no-tillage cropping system, which is a worldwide adopted agricultural conservation system. Societal benefits of conservation systems in agriculture include greater use of conservation tillage, which reduces soil erosion and associated loading of pesticides, nutrients and sediments into the environment. However, overreliance on glyphosate and simpler cropping systems has resulted in the selection of tolerant weed species through weed shifts (WSs) and evolution of herbicide-resistant weed (HRW) biotypes to glyphosate. It is a challenge in South America to design herbicide- and non-herbicide-based strategies that effectively delay and/or manage evolution of HRWs and WSs to weeds tolerant to glyphosate in cropping systems based on recurrent glyphosate application, such as those used with glyphosate-resistant soybeans. The objectives of this paper are (i) to provide an overview of some factors that influence WSs and HRWs to glyphosate in South America, especially in Brazil, Argentina and Paraguay soybean cropped areas; (ii) to discuss the viability of using crop rotation and/or cover crops that might be integrated with forage crops in an economically and environmentally sustainable system; and (iii) to summarize the results of a survey of the perceptions of Brazilian farmers to problems with WSs and HRWs to glyphosate, and the level of adoption of good agricultural practices in order to prevent or manage it. Copyright (c) 2008 Society of Chemical Industry.

  19. On Averaging Rotations

    DEFF Research Database (Denmark)

    Gramkow, Claus

    1999-01-01

    In this article two common approaches to averaging rotations are compared to a more advanced approach based on a Riemannian metric. Very offten the barycenter of the quaternions or matrices that represent the rotations are used as an estimate of the mean. These methods neglect that rotations belong...... approximations to the Riemannian metric, and that the subsequent corrections are inherient in the least squares estimation. Keywords: averaging rotations, Riemannian metric, matrix, quaternion...

  20. Management of Soilborne Diseases in Strawberry Using Vegetable Rotations

    OpenAIRE

    Subbarao, Krishna V

    2007-01-01

    The influence of crop rotation on soilborne diseases and yield of strawberry (Fragaria × ananassa) was determined at a site infested with Verticillium dahliae microsclerotia and at another with no known history of V. dahliae infestation during 1997 to 2000. The rotations studied at the V. dahliae-infested site were (i) broccoli-broccoli-strawberry, (ii) Brussels sproutsstrawberry, and (iii) lettuce-lettuce-strawberry; the treatments at the site with no history of V. dahliae were (i) broccoli-...

  1. Parameterization of rotational spectra

    International Nuclear Information System (INIS)

    Zhou Chunmei; Liu Tong

    1992-01-01

    The rotational spectra of the strongly deformed nuclei with low rotational frequencies and weak band mixture are analyzed. The strongly deformed nuclei are commonly encountered in the rare-earth region (e. g., 150 220). A lot of rotational band knowledge are presented

  2. Prospects for arable farm uptake of Short Rotation Coppice willow and miscanthus in England.

    Science.gov (United States)

    Glithero, Neryssa J; Wilson, Paul; Ramsden, Stephen J

    2013-07-01

    Biomass will play a role in the UK meeting EU targets on renewable energy use. Short Rotation Coppice (SRC) and miscanthus are potential biomass feedstocks; however, supply will rely on farmer willingness to grow these crops. Despite attractive crop establishment grants for dedicated energy crops (DECs) in the UK, uptake remains low. Drawing on results from an on-farm survey with 244 English arable farmers, 81.6% (87.7%) of farmers would not consider growing miscanthus (SRC), while respectively, 17.2% (11.9%) would consider growing and 1.2% (0.4%) were currently growing these crops. Farmer age, location, land ownership, farm type, farm size and farmer education level were not significant factors in determining acceptance of DECs. The main reasons cited for not growing DECs were impacts on land quality, lack of appropriate machinery, commitment of land for a long period of time, time to financial return and profitability. Reasons cited for willingness to grow DECs included land quality, ease of crop management, commitment of land for a long period of time, and profitability. Farmers cited a range of 'moral' (e.g. should not be using land for energy crops when there is a shortage of food), land quality, knowledge, profit and current farming practice comments as reasons for not growing DECs, while those willing to grow DECs cited interest in renewable energy, willingness to consider new crops, and low labour needs as rationale for their interest. Farm business objectives indicated that maximising profit and quality of life were most frequently cited as very important objectives. Previous research in the UK indicates that farmers in arable areas are unlikely to convert large areas of land to DECs, even where these farmers have an interest and willingness to grow them. Assuming that those farmers interested in growing DECs converted 9.29% (average percentage of arable land set-aside between 1996 and 2005) of their utilised agricultural area to these crops, 50,700

  3. Numerical simulation of cropping

    DEFF Research Database (Denmark)

    Tvergaard, Viggo; Hutchinson, John W.

    2014-01-01

    Cropping is a cutting process whereby opposing aligned blades create a shearing failure by exerting opposing forces normal to the surfaces of a metal sheet or plate. Building on recent efforts to quantify cropping, this paper formulates a plane strain elastic-plastic model of a plate subject to s...

  4. Applied Crop Protection 2017

    DEFF Research Database (Denmark)

    Jørgensen, Lise Nistrup; Nielsen, Bent Jørgen; Mathiassen, Solvejg Kopp

    Linket til højre henviser til rapporten i trykt format til download. This publication contains results from crop protection trials which were carried out at the Department of Agroecology within the area of gricultural crops. Most of the results come from field trials, but results from greenhouse ...

  5. SOIL CHEMICAL ATTRIBUTES AND LEAF NUTRIENTS OF ‘PACOVAN’ BANANA UNDER TWO COVER CROPS

    Directory of Open Access Journals (Sweden)

    JOSÉ EGÍDIO FLORI

    2016-01-01

    Full Text Available Banana is one of the most consumed fruits in the world, which is grown in most tropical countries. The objective of this work was to evaluate the main attributes of soil fertility in a banana crop under two cover crops and two root development locations. The work was conducted in Curaçá, BA, Brazil, between October 2011 and May 2013, using a randomized block design in split plot with five repetitions. Two cover crops were assessed in the plots, the cover 1 consisting of Pueraria phaseoloides, and the cover 2 consisting of a crop mix with Sorghum bicolor, Ricinus communis L., Canavalia ensiformis, Mucuna aterrima and Zea mays, and two soil sampling locations in the subplots, between plants in the banana rows (location 1 and between the banana rows (location 2. There were significant and independent effects for the cover crop and sampling location factors for the variables organic matter, Ca and P, and significant effects for the interaction between cover crops and sampling locations for the variables potassium, magnesium and total exchangeable bases. The cover crop mix and the between-row location presented the highest organic matter content. Potassium was the nutrient with the highest negative variation from the initial content and its leaf content was below the reference value, however not reducing the crop yield. The banana crop associated with crop cover using the crop mix provided greater availability of nutrients in the soil compared to the coverage with tropical kudzu.

  6. Scheduling irrigation in heterogeneous container nursery crops

    NARCIS (Netherlands)

    Incrocci, L.; Incrocci, G.; Vita, Di A.; Pardossi, A.; Bibbiani, C.; Marzialetti, P.; Balendonck, J.

    2014-01-01

    One of the major production areas in Europe for Hardy Ornamental Nursery Stocks (HONS) is located around Pistoia (Tuscany, Italy). In this area, pot ornamental crops show low water use efficiency (WUE). Main reasons of poor irrigation efficiency are both the inaccurate irrigation scheduling, which

  7. Climate-driven simulation of global crop sowing dates

    NARCIS (Netherlands)

    Waha, K.; Bussel, van L.G.J.; Müller, C.; Bondeau, A.

    2012-01-01

    Aim To simulate the sowing dates of 11 major annual crops at the global scale at high spatial resolution, based on climatic conditions and crop-specific temperature requirements. Location Global. Methods Sowing dates under rainfed conditions are simulated deterministically based on a set of rules

  8. Effects of mineral and organic fertilizers on crop productivity and ...

    African Journals Online (AJOL)

    Other two fields grown with the same crops without fertilizer application served as control treatment. In addition, a greenhouse experiment was run to ... It was concluded that biophysical factors (field location and initial soil fertility status) greatly influenced crop yield and fertilizer. Keywords: Bean, maize, fertilizer response, ...

  9. Crop model usefulness in drylands of southern Africa: an application ...

    African Journals Online (AJOL)

    Data limitations in southern Africa frequently hinder adequate assessment of crop models before application. ... three locations to represent varying cropping and physical conditions in southern Africa, i.e. maize and sorghum (Mohale's Hoek, Lesotho and Big Bend, Swaziland) and maize and groundnut (Lilongwe, Malawi).

  10. Combining the effect of crops surface albedo variability on the radiative forcing together with crop GHG budgets calculated from in situ flux measurements in a life cycle assessment approach: methodology and results

    Science.gov (United States)

    Ceschia, E.; Ferlicoq, M.; Brut, A.; Tallec, T.

    2013-12-01

    The carbon and GHG budgets (GHGB) of the 2 crop sites with contrasted management located in South West France was estimated over a complete rotation by combining a classical LCA approach with on site CO2 flux measurements. At both sites, carbon inputs (organic fertilization, seeds), carbon exports (harvest) and net ecosystem production (NEP), measured with the eddy covariance technique, were estimated. The variability of the different terms and their relative contributions to the net ecosystem carbon budget (NECB) were analyzed for all site-years, and the effect of management on NECB was assessed. To account for GHG fluxes that were not directly measured on site, we estimated the emissions caused by field operations (EFO) for each site using emission factors from the literature. The EFO were added to the NECB to calculate the total GHGB for a range of cropping systems and management regimes. N2O emissions were calculated following the IPCC (2007) guidelines or and CH4 emissions were assumed to be negligible. Albedo was calculated continuously using the short wave incident and reflected radiation measurements in the field from CNR1 sensors. Rapid changes in surface albedo typical from those ecosystems and resulting from management and crop phenology were analysed. The annual radiative forcing for each plot was estimated by calculating the difference between a mean annual albedo for each crop and a reference bare soil albedo value calculated over 5 years for each plot. To finalize the radiative forcing calculation, the method developed by Muñoz et al (2010) using up and down atmospheric transmittance had to be corrected so it would only account for up-going atmospheric transmittance. Annual differences in radiative forcing between crops were then converted in g C equivalent m-2 in order to add this effect to the GHG budget of each crop within a rotation. This methodology could be applied to all ICOS/NEON cropland sites. We found that the differences in radiative

  11. 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.

  12. Rotating Stars in Relativity

    Directory of Open Access Journals (Sweden)

    Stergioulas Nikolaos

    2003-01-01

    Full Text Available Rotating relativistic stars have been studied extensively in recent years, both theoretically and observationally, because of the information they might yield about the equation of state of matter at extremely high densities and because they are considered to be promising sources of gravitational waves. The latest theoretical understanding of rotating stars in relativity is reviewed in this updated article. The sections on the equilibrium properties and on the nonaxisymmetric instabilities in f-modes and r-modes have been updated and several new sections have been added on analytic solutions for the exterior spacetime, rotating stars in LMXBs, rotating strange stars, and on rotating stars in numerical relativity.

  13. Visualizing molecular unidirectional rotation

    Science.gov (United States)

    Lin, Kang; Song, Qiying; Gong, Xiaochun; Ji, Qinying; Pan, Haifeng; Ding, Jingxin; Zeng, Heping; Wu, Jian

    2015-07-01

    We directly visualize the spatiotemporal evolution of a unidirectional rotating molecular rotational wave packet. Excited by two time-delayed polarization-skewed ultrashort laser pulses, the cigar- or disk-shaped rotational wave packet is impulsively kicked to unidirectionally rotate as a quantum rotor which afterwards disperses and exhibits field-free revivals. The rich dynamics can be coherently controlled by varying the timing or polarization of the excitation laser pulses. The numerical simulations very well reproduce the experimental observations and intuitively revivify the thoroughgoing evolution of the molecular rotational wave packet of unidirectional spin.

  14. Key factors influencing the potential of catch crops for methane production

    DEFF Research Database (Denmark)

    Molinuevo-Salces, Beatriz; Fernandez-Varela, Raquel; Uellendahl, Hinrich

    2014-01-01

    explained up to 84.6% and 71.6% of the total variation for 2010 and 2011 samples, respectively. Specific methane yield, climate conditions (rainfall and temperature) and total nitrogen in the biomass were the variables classifying the different catch crops. Catch crops in the Brassicaceae and Graminaceae......Catch crops are grown in crop rotation primarily for soil stabilization. The excess biomass of catch crops was investigated for its potential as feedstock for biogas production. Ten variables affecting catch crop growth and methane potential were evaluated. Field trials and methane potential were...... studied for 14 different catch crops species, with 19 samples harvested in 2010 and 36 harvested in 2011. Principal component analysis was applied to the data to identify the variables characterizing the potential for the different catch crops species for methane production. Two principal components...

  15. Impact of preceding crop on alfalfa competitiveness with weeds

    Science.gov (United States)

    Organic producers would like to include no-till practices in their farming systems. We are seeking to develop a continuous no-till system for organic farming, based on a complex rotation that includes a 3-year sequence of alfalfa. In this study, we evaluated impact of preceding crop on weed infest...

  16. determinants of inorganic fertiliser use in the mixed crop- livestock ...

    African Journals Online (AJOL)

    Prof. Adipala Ekwamu

    characteristics, perception of soil degradation problem and past use of alternative soil fertility management practices (crop rotations involving legumes, farm yard manure and seasonal fallowing) are believed to be important in explaining variations in inorganic fertiliser use among smallholder farmers, yet previous studies.

  17. Effect of Cropping Practices on Weed Species Composition in a ...

    African Journals Online (AJOL)

    The effect of rotation and weeding practices on weed species composition were evaluated in a groundnut (Arachis hypogaea, L.) crop in a three-year field experiment in Central Malawi under ridge-tillage practices. Weeding practices consisted of weeding twice including earthing-up, weeding once, and no weeding, ...

  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

    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...

  19. Assessing the sustainability of wheat-based cropping systems using APSIM: Model parameterisation and evaluation

    NARCIS (Netherlands)

    Moeller, C.; Pala, M.; Manschadi, A.M.; Meinke, H.B.; Sauerborn, J.

    2007-01-01

    Assessing the sustainability of crop and soil management practices in wheat-based rotations requires a well-tested model with the demonstrated ability to sensibly predict crop productivity and changes in the soil resource. The Agricultural Production Systems Simulator (APSIM) suite of models was

  20. 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

    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...

  1. Testing the egocentric mirror-rotation hypothesis.

    Science.gov (United States)

    Muelenz, Cornelius; Hecht, Heiko; Gamer, Matthias

    2010-01-01

    Although observers know about the law of reflection, their intuitive understanding of spatial locations in mirrors is often erroneous. Hecht et al. (2005) proposed a two-stage mirror-rotation hypothesis to explain these misconceptions. The hypothesis involves an egocentric bias to the effect that observers behave as if the mirror surface were rotated by about 2 degrees to be more orthogonal than is the case. We test four variants of the hypothesis, which differ depending on whether the virtual world, the mirror, or both are taken to be rotated. We devised an experimental setup that allowed us to distinguish between these variants. Our results confirm that the virtual world--and only the virtual world--is being rotated. Observers had to perform a localization task, using a mirror that was either fronto-parallel or rotated opposite the direction of the predicted effect. We were thus able to compensate for the effect. The positions of objects in mirrors were perceived in accordance with the erroneous conception that the virtual world behind the mirror is slightly rotated and that the reconstruction is based on the non-rotated fronto-parallel mirror. A covert rotation of the mirror by about 2 degrees against the predicted effect was able to compensate for the placement error.

  2. Water footprint of crop production for different crop structures in the Hebei southern plain, North China

    Science.gov (United States)

    Chu, Yingmin; Shen, Yanjun; Yuan, Zaijian

    2017-06-01

    The North China Plain (NCP) has a serious shortage of freshwater resources, and crop production consumes approximately 75 % of the region's water. To estimate water consumption of different crops and crop structures in the NCP, the Hebei southern plain (HSP) was selected as a study area, as it is a typical region of groundwater overdraft in the NCP. In this study, the water footprint (WF) of crop production, comprised of green, blue and grey water footprints, and its annual variation were analyzed. The results demonstrated the following: (1) the WF from the production of main crops was 41.8 km3 in 2012. Winter wheat, summer maize and vegetables were the top water-consuming crops in the HSP. The water footprint intensity (WFI) of cotton was the largest, and for vegetables, it was the smallest; (2) the total WF, WFblue, WFgreen and WFgrey for 13 years (2000-2012) of crop production were 604.8, 288.5, 141.3 and 175.0 km3, respectively, with an annual downtrend from 2000 to 2012; (3) winter wheat, summer maize and vegetables consumed the most groundwater, and their blue water footprint (WFblue) accounted for 74.2 % of the total WFblue in the HSP; (4) the crop structure scenarios analysis indicated that, with approximately 20 % of arable land cultivated with winter wheat-summer maize in rotation, 38.99 % spring maize, 10 % vegetables and 10 % fruiters, a sustainable utilization of groundwater resources can be promoted, and a sufficient supply of food, including vegetables and fruits, can be ensured in the HSP.

  3. Water footprint of crop production for different crop structures in the Hebei southern plain, North China

    Directory of Open Access Journals (Sweden)

    Y. Chu

    2017-06-01

    Full Text Available The North China Plain (NCP has a serious shortage of freshwater resources, and crop production consumes approximately 75 % of the region's water. To estimate water consumption of different crops and crop structures in the NCP, the Hebei southern plain (HSP was selected as a study area, as it is a typical region of groundwater overdraft in the NCP. In this study, the water footprint (WF of crop production, comprised of green, blue and grey water footprints, and its annual variation were analyzed. The results demonstrated the following: (1 the WF from the production of main crops was 41.8 km3 in 2012. Winter wheat, summer maize and vegetables were the top water-consuming crops in the HSP. The water footprint intensity (WFI of cotton was the largest, and for vegetables, it was the smallest; (2 the total WF, WFblue, WFgreen and WFgrey for 13 years (2000–2012 of crop production were 604.8, 288.5, 141.3 and 175.0 km3, respectively, with an annual downtrend from 2000 to 2012; (3 winter wheat, summer maize and vegetables consumed the most groundwater, and their blue water footprint (WFblue accounted for 74.2 % of the total WFblue in the HSP; (4 the crop structure scenarios analysis indicated that, with approximately 20 % of arable land cultivated with winter wheat–summer maize in rotation, 38.99 % spring maize, 10 % vegetables and 10 % fruiters, a sustainable utilization of groundwater resources can be promoted, and a sufficient supply of food, including vegetables and fruits, can be ensured in the HSP.

  4. Principles and practices of using cover crops in weed management systems

    OpenAIRE

    Teasdale, J.

    2003-01-01

    Metadata only record Cover crops are plant species that are introduced into crop rotations to provide beneficial services to the agro-ecosystem. Some of the most important environmental services provided by cover crops include soil protection from erosion, capture and prevention of soil nutrient losses, fixation of nitrogen by legumes, increase in soil carbon and associated improvements in soil physical and chemical characteristics, decrease in soil temperature, increase in biological dive...

  5. Crop resources. [18 papers

    Energy Technology Data Exchange (ETDEWEB)

    Seigler, D.S. (ed.)

    1977-01-01

    Eighteen papers originally presented as a symposium on Crop Resources at the 17th annual meeting of the Society for Economic Botany in Urbana, Illinois, June 13 to 17, 1976 comprise this book. The papers are: Potential Wealth in New Crops: Research and Development, L. H. Princen; Plant Introductions--A Source of New Crops, George A. White; Nonfood Uses for Commercial Vegetable Oil Crops, E. H. Pryde; New Industrial Potentials for Carbohydrates, F. H. Otey; The Current Importance of Plants as a Source of Drugs, Norman R. Farnsworth; Potentials for Development of Wild Plants as Row Crops for Use by Man, Arnold Krochmal and Connie Krochmal; Recent Evidence in Support of the Tropical Origin of New World Crops, C. Earle Smith, Jr.; Requirements for a Green Revolution, G. F. Sprague; How Green Can a Revolution Be, Jack R. Harlan; Increasing Cereal Yields: Evolution under Domestication, J. M. J. de Wet; Hevea Rubber: Past and Future, Ernest P. Imle; Horseradish--Problems and Research in Illinois, A. M. Rhodes; Dioscorea--The Pill Crop, Norman Applezweig; Plant Derivatives for Insect Control, Robert L. Metcalf; Evolutionary Dynamics of Sorghum Domestication, J. M. J. de Wet and Y. Shecter; The Origin and Future of Wheat, E. R. Sears; Current Thoughts on Origins, Present Status, and Future of Soybeans, T. Hymowitz and C. A. Newell; and The Origin of Corn--Studies of the Last Hundred Years, Garrison Wilkes. (MCW)

  6. Secular stability of rotating stars

    International Nuclear Information System (INIS)

    Imamura, J.N.; Friedman, J.L.; Durisen, R.H.

    1984-01-01

    In this work, we calculate the secular stability limits of rotating polytropes to nonaxisymmetric perturbations of low m. We consider polytropic indices ranging from 1 to 3 and several angular momentum distributions. Results are most conveniently presented in terms of the t-parameter, defined as the ratio of the rotational kinetic energy to the absolute value of the gravitational energy of the fluid. Previous work on polytropes considered only the m = 2 mode, which is unstable for values of the t-parameter greater than 0.14 +- 0.01 for the n values n = 1.5 and 3 and the angular momentum distributions tested (see Durisen and Imamura 1981). The GRR secular stability limit of the m = 2 mode for the Maclaurin spheroids (n = O) was determined by Chandrasekhar (1970). GRR stability limits of higher m modes for the Maclaurin spheroids were located approximately by Comins (1979a,b) and more precisely by Friedman (1983)

  7. Management of Overwintering Cover Crops Influences Floral Resources and Visitation by Native Bees.

    Science.gov (United States)

    Ellis, Katherine E; Barbercheck, Mary E

    2015-08-01

    The incorporation of cover crops into annual crop rotations is one practice that is used in the Mid-Atlantic United States to manage soil fertility, suppress weeds, and control erosion. Additionally, flowering cover crops have the potential to support beneficial insect communities, such as native bees. Because of the current declines in managed honey bee colonies, the conservation of native bee communities is critical to maintaining "free" pollination services. However, native bees are negatively affected by agricultural intensification and are also in decline across North America. We conducted two experiments to assess the potential of flowering cover crops to act as a conservation resource for native bees. We evaluated the effects of cover crop diversity and fall planting date on floral resource availability and visitation by native bees for overwintering flowering cover crop species commonly used in the Mid-Atlantic region. Cover crop species, crop rotation schedule, and plant diversity significantly influenced floral resource availability. Different cover crop species not only had different blooming phenologies and winter survival responses to planting date, but attracted unique bee communities. Flower density was the primary factor influencing frequency of bee visitation across cover crop diversity and fall planting date treatments. The results from these experiments will be useful for informing recommendations on the applied use of flowering cover crops for pollinator conservation purposes. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Life Cycle Inventory Modelling of Land Use Induced by Crop Consumption

    DEFF Research Database (Denmark)

    Kløverpris, Jesper; Wenzel, Henrik; Nielsen, Per Henning

    2008-01-01

    . Based on the current market trend for crops and an analysis of basic mechanisms in crop production, concepts for modelling how crop consumption affects the global agricultural area and the intensity of crop production are suggested. It is demonstrated how the assumptions concerning drivers...... for technological development have a profound influence on identification of the marginal response to crop consumption, and how the geographical location of crop consumption also influences the composition of the marginal production response in terms of cropland expansion and intensification. Crop prices have been...... falling at a global scale and are projected to decline further. At the same time, crop yields per hectare are continuously increasing. This indicates that drivers other than crop demand have a strong influence on technological development in crop production. Economic modelling in combination...

  9. Controlled sample orientation and rotation in an acoustic levitator

    Science.gov (United States)

    Barmatz, Martin B. (Inventor); Gaspar, Mark S. (Inventor); Trinh, Eugene H. (Inventor)

    1988-01-01

    A system is described for use with acoustic levitators, which can prevent rotation of a levitated object or control its orientation and/or rotation. The acoustic field is made nonsymmetrical about the axis of the levitator, to produce an orienting torque that resists sample rotation. In one system, a perturbating reflector is located on one side of the axis of the levitator, at a location near the levitated object. In another system, the main reflector surface towards which incoming acoustic waves are directed is nonsymmetrically curved about the axis of the levitator. The levitated object can be reoriented or rotated in a controlled manner by repositioning the reflector producing the nonsymmetry.

  10. 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.

  11. Implications of observed and simulated soil carbon sequestration for management options in corn-based rotations

    Science.gov (United States)

    Managing cropping systems to sequester soil organic carbon (SOC) improves soil health and a system’s resiliency to impacts of changing climate. Our objectives were to 1) monitor SOC from a bio-energy cropping study in central Pennsylvania that included a corn-soybean-alfalfa rotation, switchgrass, ...

  12. Emission of CO2 from energy crop production

    International Nuclear Information System (INIS)

    Turhollow, A.F.

    1991-01-01

    The production of cellulosic energy crops (e.g., short rotation woody crops and herbaceous crops) make a net contribution of CO 2 to the atmosphere to the extent that fossil-fuel based inputs are used in their production. The CO 2 released from the use of the biomass is merely CO 2 that has recently been removed from the atmosphere by the plant growth process. Fossil inputs used in the production of energy corps include energy invested in fertilizers and pesticides, and petroleum fuels used for machinery operation such as site preparation, weed control, harvesting, and hauling. Fossil inputs used come from petroleum, natural gas, and electricity derived from fossil sources. No fossil inputs for the capital used to produce fertilizers, pesticides, or machinery is calculated in this analysis. In this paper calculations are made for the short rotation woody crop hybrid poplar (Populus spp.), the annual herbaceous crop sorghum (Sorghum biocolor [L.] Moench), and the perennial herbaceous crop switchgrass (Panicum virgatum L.). For comparison purposes, emissions of CO 2 from corn (Zea mays L.) are calculated

  13. Perennial Forages as Second Generation Bioenergy Crops

    Directory of Open Access Journals (Sweden)

    Paul R. Adler

    2008-05-01

    Full Text Available The lignocellulose in forage crops represents a second generation of biomass feedstock for conversion into energy-related end products. Some of the most extensively studied species for cellulosic feedstock production include forages such as switchgrass (Panicum virgatum L., reed canarygrass (Phalaris arundinacea L., and alfalfa (Medicago sativa L.. An advantage of using forages as bioenergy crops is that farmers are familiar with their management and already have the capacity to grow, harvest, store, and transport them. Forage crops offer additional flexibility in management because they can be used for biomass or forage and the land can be returned to other uses or put into crop rotation. Estimates indicate about 22.3 million ha of cropland, idle cropland, and cropland pasture will be needed for biomass production in 2030. Converting these lands to large scale cellulosic energy farming could push the traditional forage-livestock industry to ever more marginal lands. Furthermore, encouraging bioenergy production from marginal lands could directly compete with forage-livestock production.

  14. Yields of Selected Catch Crops in Dry Conditions

    Directory of Open Access Journals (Sweden)

    Martina Handlířová

    2016-01-01

    Full Text Available Catch crops mainly reduce soil erosion and leaching of nutrients as well as enrich the soil organic matter. The aim of this research is to evaluate the yields of catch crops of Sinapis alba, Phacelia tanacetifolia, Fagopyrum esculentum, Carthamus tinctorius and Secale cereale v. multicaule, and thus determine the possible applicability of catch crops in areas with high average annual temperature and low precipitation totals. The small-plot field experiment was performed on clay-loam gleyic fluvisol at the Field Experimental Station in Žabčice, Southern Moravia, Czech Republic, within the period of 2006-2014. The catch crops were set up after winter wheat in mid-August. The results have shown a statistically significant difference among different catch crops in yield of dry matter and even among years. The yield of catch crops is mainly dependent on a sufficient supply of water in the soil and the appropriate amount and distribution of rainfall over the growing season. Sinapis alba and Phacelia tanacetifolia regularly reached the highest yields. High yields were also achieved with Fagopyrum esculentum. Due to the method of crop rotation in the Czech Republic, with a predominance of Brassica napus var. napus, it is inappropriate to include Sinapis alba. It is the best to grow Phacelia tanacetifolia and even Fagopyrum esculentum, or a mixture thereof, depending on the use of catch crops.

  15. Perennial Forages as Second Generation Bioenergy Crops

    Science.gov (United States)

    Sanderson, Matt A.; Adler, Paul R.

    2008-01-01

    The lignocellulose in forage crops represents a second generation of biomass feedstock for conversion into energy-related end products. Some of the most extensively studied species for cellulosic feedstock production include forages such as switchgrass (Panicum virgatum L.), reed canarygrass (Phalaris arundinacea L.), and alfalfa (Medicago sativa L.). An advantage of using forages as bioenergy crops is that farmers are familiar with their management and already have the capacity to grow, harvest, store, and transport them. Forage crops offer additional flexibility in management because they can be used for biomass or forage and the land can be returned to other uses or put into crop rotation. Estimates indicate about 22.3 million ha of cropland, idle cropland, and cropland pasture will be needed for biomass production in 2030. Converting these lands to large scale cellulosic energy farming could push the traditional forage-livestock industry to ever more marginal lands. Furthermore, encouraging bioenergy production from marginal lands could directly compete with forage-livestock production. PMID:19325783

  16. Cereal Crops Research Unit

    Data.gov (United States)

    Federal Laboratory Consortium — The mission of the Cereal Crops Research Unit is to 1) conduct basic research to identify and understand the biological processes affecting the growth, development...

  17. Rotations with Rodrigues' vector

    International Nuclear Information System (INIS)

    Pina, E

    2011-01-01

    The rotational dynamics was studied from the point of view of Rodrigues' vector. This vector is defined here by its connection with other forms of parametrization of the rotation matrix. The rotation matrix was expressed in terms of this vector. The angular velocity was computed using the components of Rodrigues' vector as coordinates. It appears to be a fundamental matrix that is used to express the components of the angular velocity, the rotation matrix and the angular momentum vector. The Hamiltonian formalism of rotational dynamics in terms of this vector uses the same matrix. The quantization of the rotational dynamics is performed with simple rules if one uses Rodrigues' vector and similar formal expressions for the quantum operators that mimic the Hamiltonian classical dynamics.

  18. An identification of potential new herbicides for short rotation coppice (Task 4). Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    This report summarises the findings of a project to identify potential new herbicides and their suitability for weed control in commercial short rotation coppice (SRC) crops, and to establish the safety of the crops. The arrangements for the use of 'off-label' pesticides, which are permitted for use on other crops, on SRC are discussed along with the importance of the use of laboratory pot trials and field trials. Several herbicides are proposed for larger scale field trials.

  19. Transgenics in crops

    Science.gov (United States)

    Li, Y.; Wu, Y. H.; McAvoy, R.; Duan, H.

    2001-01-01

    With rapid world population growth and declining availability of fresh water and arable land, a new technology is urgently needed to enhance agricultural productivity. Recent discoveries in the field of crop transgenics clearly demonstrate the great potential of this technology for increasing food production and improving food quality while preserving the environment for future generations. In this review, we briefly discuss some of the recent achievements in crop improvement that have been made using gene transfer technology.

  20. Radioactivity in food crops

    Energy Technology Data Exchange (ETDEWEB)

    Drury, J.S.; Baldauf, M.F.; Daniel, E.W.; Fore, C.S.; Uziel, M.S.

    1983-05-01

    Published levels of radioactivity in food crops from 21 countries and 4 island chains of Oceania are listed. The tabulation includes more than 3000 examples of 100 different crops. Data are arranged alphabetically by food crop and geographical origin. The sampling date, nuclide measured, mean radioactivity, range of radioactivities, sample basis, number of samples analyzed, and bibliographic citation are given for each entry, when available. Analyses were reported most frequently for /sup 137/Cs, /sup 40/K, /sup 90/Sr, /sup 226/Ra, /sup 228/Ra, plutonium, uranium, total alpha, and total beta, but a few authors also reported data for /sup 241/Am, /sup 7/Be, /sup 60/Co, /sup 55/Fe, /sup 3/H, /sup 131/I, /sup 54/Mn, /sup 95/Nb, /sup 210/Pb, /sup 210/Po, /sup 106/Ru, /sup 125/Sb, /sup 228/Th, /sup 232/Th, and /sup 95/Zr. Based on the reported data it appears that radioactivity from alpha emitters in food crops is usually low, on the order of 0.1 Bq.g/sup -1/ (wet weight) or less. Reported values of beta radiation in a given crop generally appear to be several orders of magnitude greater than those of alpha emitters. The most striking aspect of the data is the great range of radioactivity reported for a given nuclide in similar food crops with different geographical origins.

  1. Radioactivity in food crops

    International Nuclear Information System (INIS)

    Drury, J.S.; Baldauf, M.F.; Daniel, E.W.; Fore, C.S.; Uziel, M.S.

    1983-05-01

    Published levels of radioactivity in food crops from 21 countries and 4 island chains of Oceania are listed. The tabulation includes more than 3000 examples of 100 different crops. Data are arranged alphabetically by food crop and geographical origin. The sampling date, nuclide measured, mean radioactivity, range of radioactivities, sample basis, number of samples analyzed, and bibliographic citation are given for each entry, when available. Analyses were reported most frequently for 137 Cs, 40 K, 90 Sr, 226 Ra, 228 Ra, plutonium, uranium, total alpha, and total beta, but a few authors also reported data for 241 Am, 7 Be, 60 Co, 55 Fe, 3 H, 131 I, 54 Mn, 95 Nb, 210 Pb, 210 Po, 106 Ru, 125 Sb, 228 Th, 232 Th, and 95 Zr. Based on the reported data it appears that radioactivity from alpha emitters in food crops is usually low, on the order of 0.1 Bq.g -1 (wet weight) or less. Reported values of beta radiation in a given crop generally appear to be several orders of magnitude greater than those of alpha emitters. The most striking aspect of the data is the great range of radioactivity reported for a given nuclide in similar food crops with different geographical origins

  2. Passive RFID Rotation Dimension Reduction via Aggregation

    Science.gov (United States)

    Matthews, Eric

    Radio Frequency IDentification (RFID) has applications in object identification, position, and orientation tracking. RFID technology can be applied in hospitals for patient and equipment tracking, stores and warehouses for product tracking, robots for self-localisation, tracking hazardous materials, or locating any other desired object. Efficient and accurate algorithms that perform localisation are required to extract meaningful data beyond simple identification. A Received Signal Strength Indicator (RSSI) is the strength of a received radio frequency signal used to localise passive and active RFID tags. Many factors affect RSSI such as reflections, tag rotation in 3D space, and obstacles blocking line-of-sight. LANDMARC is a statistical method for estimating tag location based on a target tag's similarity to surrounding reference tags. LANDMARC does not take into account the rotation of the target tag. By either aggregating multiple reference tag positions at various rotations, or by determining a rotation value for a newly read tag, we can perform an expected value calculation based on a comparison to the k-most similar training samples via an algorithm called K-Nearest Neighbours (KNN) more accurately. By choosing the average as the aggregation function, we improve the relative accuracy of single-rotation LANDMARC localisation by 10%, and any-rotation localisation by 20%.

  3. Projective analysis of staple food crop productivity in adaptation to future climate change in China

    Science.gov (United States)

    Zhang, Qing; Zhang, Wen; Li, Tingting; Sun, Wenjuan; Yu, Yongqiang; Wang, Guocheng

    2017-08-01

    Climate change continually affects our capabilities to feed the increasing population. Rising temperatures have the potential to shorten the crop growth duration and therefore reduce crop yields. In the past decades, China has successfully improved crop cultivars to stabilize, and even lengthen, the crop growth duration to make use of increasing heat resources. However, because of the complex cropping systems in the different regions of China, the possibility and the effectiveness of regulating crop growth duration to reduce the negative impacts of future climate change remain questionable. Here, we performed a projective analysis of the staple food crop productivity in double-rice, wheat-rice, wheat-maize, single-rice, and single-maize cropping systems in China using modeling approaches. The results indicated that from the present to the 2040s, the warming climate would shorten the growth duration of the current rice, wheat, and maize cultivars by 2-24, 11-13, and 9-29 days, respectively. The most significant shortening of the crop growth duration would be in Northeast China, where single-rice and single-maize cropping dominates the croplands. The shortened crop growth duration would consequently reduce crop productivity. The most significant decreases would be 27-31, 6-20, and 7-22% for the late crop in the double-rice rotation, wheat in the winter wheat-rice rotation, and single maize, respectively. However, our projection analysis also showed that the negative effects of the warming climate could be compensated for by stabilizing the growth duration of the crops via improvement in crop cultivars. In this case, the productivity of rice, wheat, and maize in the 2040s would increase by 4-16, 31-38, and 11-12%, respectively. Our modeling results implied that the possibility of securing future food production exists by adopting proper adaptation options in China.

  4. Addressing crop interactions within cropping systems in LCA

    DEFF Research Database (Denmark)

    Goglio, Pietro; Brankatschk, Gerhard; Knudsen, Marie Trydeman

    2018-01-01

    objectives of this discussion article are as follows: (i) to discuss the characteristics of cropping systems which might affect the LCA methodology, (ii) to discuss the advantages and the disadvantages of the current available methods for the life-cycle assessment of cropping systems, and (iii) to offer...... management and emissions, and (3) functional unit issues. The LCA approaches presented are as follows: cropping system, allocation approaches, crop-by-crop approach, and combined approaches. The various approaches are described together with their advantages and disadvantages, applicability...... considers cropping system issues if they are related to multiproduct and nutrient cycling, while the crop-by-crop approach is highly affected by assumptions and considers cropping system issues only if they are related to the analyzed crop. Conclusions Each LCA approach presents advantages and disadvantages...

  5. Remote sensing to monitor cover crop adoption in southeastern Pennsylvania

    Science.gov (United States)

    Hively, Wells; Sjoerd Duiker,; Greg McCarty,; Prabhakara, Kusuma

    2015-01-01

    In the Chesapeake Bay Watershed, winter cereal cover crops are often planted in rotation with summer crops to reduce the loss of nutrients and sediment from agricultural systems. Cover crops can also improve soil health, control weeds and pests, supplement forage needs, and support resilient cropping systems. In southeastern Pennsylvania, cover crops can be successfully established following corn (Zea mays L.) silage harvest and are strongly promoted for use in this niche. They are also planted following corn grain, soybean (Glycine max L.), and vegetable harvest. In Pennsylvania, the use of winter cover crops for agricultural conservation has been supported through a combination of outreach, regulation, and incentives. On-farm implementation is thought to be increasing, but the actual extent of cover crops is not well quantified. Satellite imagery can be used to map green winter cover crop vegetation on agricultural fields and, when integrated with additional remote sensing data products, can be used to evaluate wintertime vegetative groundcover following specific summer crops. This study used Landsat and SPOT (System Probatoire d’ Observation de la Terre) satellite imagery, in combination with the USDA National Agricultural Statistics Service Cropland Data Layer, to evaluate the extent and amount of green wintertime vegetation on agricultural fields in four Pennsylvania counties (Berks, Lebanon, Lancaster, and York) from 2010 to 2013. In December of 2010, a windshield survey was conducted to collect baseline data on winter cover crop implementation, with particular focus on identifying corn harvested for silage (expected earlier harvest date and lower levels of crop residue), versus for grain (expected later harvest date and higher levels of crop residue). Satellite spectral indices were successfully used to detect both the amount of green vegetative groundcover and the amount of crop residue on the surveyed fields. Analysis of wintertime satellite imagery

  6. Interactions of a hairy vetch-corn rotation and P fertilizer on the NPK ...

    African Journals Online (AJOL)

    Jane

    2011-08-17

    Aug 17, 2011 ... corn (Zea mays L.) rotation system in a highland area of Yunnan Province, China. Effects of phosphate. (P) fertilization, combined with hairy vetch returned to the soil, on crop yield and soil fertility were studied, and the balances of nitrogen (N), phosphorus (P) and potassium (K) in the rotation system.

  7. Canola-Wheat Rotation versus Continuous Wheat for the Southern Plains

    OpenAIRE

    Duke, Jason C.; Epplin, Francis M.; Vitale, Jeffrey D.; Peeper, Thomas F.

    2009-01-01

    Crop rotations are not common in the wheat belt of the Southern Plains. After years of continuous wheat, weeds have become increasingly difficult and expensive to manage. Yield data were elicited from farmers and used to determine if canola-wheat-wheat rotations are economically competitive with continuous wheat in the region.

  8. Pressure Transducer Locations

    Data.gov (United States)

    National Aeronautics and Space Administration — Files are located here, defining the locations of the pressure transducers on the HIRENASD model. These locations also correspond to the locations that analysts...

  9. Rice crop risk map in Babahoyo canton (Ecuador)

    Science.gov (United States)

    Valverde Arias, Omar; Tarquis, Ana; Garrido, Alberto

    2016-04-01

    It is widely known that extreme climatic phenomena occur with more intensity and frequency. This fact has put more pressure over farming, making agricultural and livestock production riskier. In order to reduce hazards and economic loses that could jeopardize farmer's incomes and even its business continuity, it is very important to implement agriculture risk management plans by governments and institutions. One of the main strategies is transfer risk by agriculture insurance. Agriculture insurance based in indexes has a significant growth in the last decade. And consist in a comparison between measured index values with a defined threshold that triggers damage losses. However, based index insurance could not be based on an isolated measurement. It is necessary to be integrated in a complete monitoring system that uses many sources of information and tools. For example, index influence areas, crop production risk maps, crop yields, claim statistics, and so on. Crop production risk is related with yield variation of crops and livestock, due to weather, pests, diseases, and other factors that affect both the quantity and quality of commodities produced. This is the risk which farmers invest more time managing, and it is completely under their control. The aim of this study is generate a crop risk map of rice that can provide risk manager important information about the status of crop facing production risks. Then, based on this information, it will be possible to make best decisions to deal with production risk. The rice crop risk map was generated qualifying a 1:25000 scale soil and climatic map of Babahoyo canton, which is located in coast region of Ecuador, where rice is one of the main crops. The methodology to obtain crop risk map starts by establishing rice crop requirements and indentifying the risks associated with this crop. A second step is to evaluate soil and climatic conditions of the study area related to optimal crop requirements. Based on it, we can

  10. Global gridded crop model evaluation

    NARCIS (Netherlands)

    Müller, Christoph; Elliott, Joshua; Chryssanthacopoulos, James; Arneth, Almut; Balkovic, Juraj; Ciais, Philippe; Deryng, Delphine; Folberth, Christian; Glotter, Michael; Hoek, Steven; Iizumi, Toshichika; Izaurralde, Roberto C.; Jones, Curtis; Khabarov, Nikolay; Lawrence, Peter; Liu, Wenfeng; Olin, Stefan; Pugh, Thomas A.M.; Ray, Deepak K.; Reddy, Ashwan; Rosenzweig, Cynthia; Ruane, Alex C.; Sakurai, Gen; Schmid, Erwin; Skalsky, Rastislav; Song, Carol X.; Wang, Xuhui; Wit, De Allard; Yang, Hong

    2017-01-01

    Crop models are increasingly used to simulate crop yields at the global scale, but so far there is no general framework on how to assess model performance. Here we evaluate the simulation results of 14 global gridded crop modeling groups that have contributed historic crop yield simulations for

  11. Biotechnology: herbicide-resistant crops

    Science.gov (United States)

    Transgenic, herbicide-resistant (HR) crops are planted on about 80% of the land covered by transgenic crops. More than 90% of HR crios are glyphosate-resistant (GR) crops, the others being resistant to glufosinate. The wide-scale adoption of HR crops, largely for economic reasons, has been the mos...

  12. Grand challenges for crop science

    Science.gov (United States)

    Crop science is a highly integrative science using the disciplines of conventional plant breeding, transgenic crop improvement, plant physiology, and cropping system sciences to develop improved varieties of agronomic, turf, and forage crops to produce feed, food, fuel, and fiber for our world's gro...

  13. Carbon dioxide and methane fluxes from legumes based rotations under conventional and organic practices

    Science.gov (United States)

    Sánchez-Navarro, Virginia; Zornoza, Raúl; Faz, Ángel; Fernández, Juan A.

    2017-04-01

    In this study we assessed the effect of two different rotations based on winter (faba bean) or summer (cowpea) legumes on the direct emissions of CO2 and CH4. Faba bean was rotated with the summer melon crop (Cucumis melo) while cowpea was rotated with the winter broccoli crop (Brassica oleracea). We also assessed if different legume cultivars and management practices (conventional and organic) significantly influenced gas emissions. The study was randomly designed in blocks with four replications, in plots of 10 m2, during two complete cycles. Gas samples were taken in different times (0, 30 and 60 minutes) once a week using the static gas chamber technique for each crop. Results showed that cumulative CO2 emissions in broccoli decreased after the rotation with both cowpea cultivars under conventional management practices. Faba bean cultivars and management practices had no influence on cumulative CO2 emissions in melon crop. Cumulative CH4 emissions in broccoli crop were lowest after the rotation with Grey-eyed pea than Black-eyed pea cultivar, under both management practices. However, faba bean cultivars and management practices had no influence on cumulative CH4 emissions in melon crop. Cumulative CH4 emissions in melon crop were highest than in the rest of crops. Cowpea cultivar and management practice influenced cumulative CH4 and CO2 emissions of broccoli crop, respectively. Faba bean cultivar and management practice had no effect on cumulative CH4 and CO2 emissions of melon crop. Acknowledgements: This research was financed by the FP7 European Project Eurolegume (FP7-KBBE-613781).

  14. Harvester development for new high yielding SRC crops and markets

    International Nuclear Information System (INIS)

    Paulson, Mark

    2005-01-01

    This report describes the development of harvesting equipment for short rotation cultivation (SRC) crops produced in the UK that can produce fuel to a required specification in a single pass at a cost that is profitable for the grower while minimising the cost of the product. Details are given of the manufacture and installation of new components for large crop harvesting, and production of fuel suitable for co-firing in a coal combustion system using pulverised fuel and fuel suitable for gasification. The development of the drive chain to cope with the higher yielding crops, field tests on SRC crops, and determination of the most economic harvesting system are discussed along with the remanufacture of the chipping drum, and production of market chip samples. Harvesting guidance and an economic analysis of harvesting systems are presented

  15. Energy from field crops

    Energy Technology Data Exchange (ETDEWEB)

    Zubr, J.

    1990-04-15

    At the Research Station of Royal Veterinary and Agricultural University, Copenhagen, Denmark, investigation concerning cultivation and exploitation of field crops for production of fuels was carried out during the period 1986-1989. High yielding crops, such as sugar beet - BETA VULGARIS, jerusalem artichoke - HELIANTHUS TUBEROSUS, rhubarb - RHEUM RHAPONTICUM, and comfrey - SYMPHYTUM ASPERUM, were grown experimentally in the field. Different cultivation methods for the crops were used and evaluated. Simultaneously with the field experiment, laboratory investigation was carried out to determine the energy potential of different products and by-products from the crops processes, such as alcoholic and methanogenic fermantation. Production expenses for the crops were determined, and cost of the fuels was estimated. The experimental results show that beet is a superior crop for the climatic conditions of Northern Europe. In the season 1986, yields exceeded 20 t TS/ha in the form of roots and tops, where achieved. A combined exploitation of beet roots and tops via alcoholic and methanogenic fermantation gave a gross energy corresponding to 80 hl OE/ha/yr. Using methanogenic fermentation exclusively, from ensiled beet roots and tops, gross energy yield corresponding to 85 hl IE/ha/yr, was achieved. The cost of energy in the form of alcohol from beet roots was estimated to be 5.17 DKK/1 OE (0.64 ECU/l OE). The cost of energy in the form of methane from ensiled beet tops, was estimated to be 2.68 DKK/l OE (0.33 ECU/l OE). At the present time, methane produced on the basis of ensiled beet roots and tops appears to be competitive with fossil fuels. Irrespective of the cost, however, the possibility of producing clean energy from field crops remains of interest for the future. (author) 27 refs.

  16. Alternative Crops and Biofuel Production

    Energy Technology Data Exchange (ETDEWEB)

    Kenkel, Philip [Oklahoma State Univ., Stillwater, OK (United States); Holcomb, Rodney B. [Oklahoma State Univ., Stillwater, OK (United States)

    2013-03-01

    In order for the biofuel industry to meet the RFS benchmarks for biofuels, new feedstock sources and production systems will have to be identified and evaluated. The Southern Plains has the potential to produce over a billion gallons of biofuels from regionally produced alternative crops, agricultural residues, and animal fats. While information on biofuel conversion processes is available, it is difficult for entrepreneurs, community planners and other interested individuals to determine the feasibility of biofuel processes or to match production alternatives with feed stock availability and community infrastructure. This project facilitates the development of biofuel production from these regionally available feed stocks. Project activities are concentrated in five major areas. The first component focused on demonstrating the supply of biofuel feedstocks. This involves modeling the yield and cost of production of dedicated energy crops at the county level. In 1991 the DOE selected switchgrass as a renewable source to produce transportation fuel after extensive evaluations of many plant species in multiple location (Caddel et al,. 2010). However, data on the yield and cost of production of switchgrass are limited. This deficiency in demonstrating the supply of biofuel feedstocks was addressed by modeling the potential supply and geographic variability of switchgrass yields based on relationship of available switchgrass yields to the yields of other forage crops. This model made it possible to create a database of projected switchgrass yields for five different soil types at the county level. A major advantage of this methodology is that the supply projections can be easily updated as improved varieties of switchgrass are developed and additional yield data becomes available. The modeling techniques are illustrated using the geographic area of Oklahoma. A summary of the regional supply is then provided.

  17. Cover cropping under temperate conditions: influence of growth period and incorporation time

    DEFF Research Database (Denmark)

    Thomsen, Ingrid Kaag; Hansen, Elly Møller

    Cover crops (CC) are generally followed by spring sown crops which limits the use of winter cereals in a crop rotation. A change from winter cereals as e.g. winter wheat (Triticum aestivum L.) to a spring sown crop as barley (Hordeum vulgare L.) often results in a reduction in grain yield....... To encourage increased use of CC and to lessen the consequences on choice of main crop new innovative ways of using CC should be considered. This study tested the potential for using CC that could allow for repeated winter wheat growing and still permit CC in breaks between crops. Cruciferous CC (Raphanus...... sativus L., Sinapis alba L.) spread in a growing winter wheat crop in July and incorporated in September (Autumn CC) before sowing the following winter wheat was compared with the same CC cultivars sown after harvest and incorporated in spring (Winter CC). The cruciferous CC were compared with Winter CC...

  18. The spatial rotator

    DEFF Research Database (Denmark)

    Rasmusson, Allan; Hahn, Ute; Larsen, Jytte Overgaard

    2013-01-01

    This paper presents a new local volume estimator, the spatial rotator, which is based on measurements on a virtual 3D probe, using computer assisted microscopy. The basic design of the probe builds upon the rotator principle which requires only a few manual intersection markings, thus making...

  19. Units of rotational information

    Science.gov (United States)

    Yang, Yuxiang; Chiribella, Giulio; Hu, Qinheping

    2017-12-01

    Entanglement in angular momentum degrees of freedom is a precious resource for quantum metrology and control. Here we study the conversions of this resource, focusing on Bell pairs of spin-J particles, where one particle is used to probe unknown rotations and the other particle is used as reference. When a large number of pairs are given, we show that every rotated spin-J Bell state can be reversibly converted into an equivalent number of rotated spin one-half Bell states, at a rate determined by the quantum Fisher information. This result provides the foundation for the definition of an elementary unit of information about rotations in space, which we call the Cartesian refbit. In the finite copy scenario, we design machines that approximately break down Bell states of higher spins into Cartesian refbits, as well as machines that approximately implement the inverse process. In addition, we establish a quantitative link between the conversion of Bell states and the simulation of unitary gates, showing that the fidelity of probabilistic state conversion provides upper and lower bounds on the fidelity of deterministic gate simulation. The result holds not only for rotation gates, but also to all sets of gates that form finite-dimensional representations of compact groups. For rotation gates, we show how rotations on a system of given spin can simulate rotations on a system of different spin.

  20. Deconstructing Mental Rotation

    DEFF Research Database (Denmark)

    Larsen, Axel

    2014-01-01

    A random walk model of the classical mental rotation task is explored in two experiments. By assuming that a mental rotation is repeated until sufficient evidence for a match/mismatch is obtained, the model accounts for the approximately linearly increasing reaction times (RTs) on positive trials...

  1. The rotating universe

    International Nuclear Information System (INIS)

    Ruben, G.; Treder, H.J.

    1987-01-01

    For a long time the question whether the universe rotates or not is discussed. Aspects of Huygens, Newton, Mach and other important historical scientists in this field are reported. The investigations of the mathematician Kurt Groedel in order to prove the rotation of the universe are illustrated. Kurt Groedel has shown that Einstein's gravitational equations of general relativity theory and the cosmological postulate of global homogeneity of cosmic matter (that is the Copernical principle) are not contradictionary to a rotating universe. Abberation measurements, position determination by means of radiointerferometry and methods for the determination of the rotation of the universe from the isotropy of the background radiation are presented. From these experiments it can be concluded that the universe seems not to rotate as already Einstein expected

  2. Rotation sensor switch

    International Nuclear Information System (INIS)

    Sevec, J.B.

    1978-01-01

    A protective device to provide a warning if a piece of rotating machinery slows or stops is comprised of a pair of hinged weights disposed to rotate on a rotating shaft of the equipment. When the equipment is rotating, the weights remain in a plane essentially perpendicular to the shaft and constitute part of an electrical circuit that is open. When the shaft slows or stops, the weights are attracted to a pair of concentric electrically conducting disks disposed in a plane perpendicular to the shaft and parallel to the plane of the weights when rotating. A disk magnet attracts the weights to the electrically conducting plates and maintains the electrical contact at the plates to complete an electrical circuit that can then provide an alarm signal

  3. Rotating stars in relativity.

    Science.gov (United States)

    Paschalidis, Vasileios; Stergioulas, Nikolaos

    2017-01-01

    Rotating relativistic stars have been studied extensively in recent years, both theoretically and observationally, because of the information they might yield about the equation of state of matter at extremely high densities and because they are considered to be promising sources of gravitational waves. The latest theoretical understanding of rotating stars in relativity is reviewed in this updated article. The sections on equilibrium properties and on nonaxisymmetric oscillations and instabilities in f -modes and r -modes have been updated. Several new sections have been added on equilibria in modified theories of gravity, approximate universal relationships, the one-arm spiral instability, on analytic solutions for the exterior spacetime, rotating stars in LMXBs, rotating strange stars, and on rotating stars in numerical relativity including both hydrodynamic and magnetohydrodynamic studies of these objects.

  4. The rotational elements of Mars and its satellites

    Science.gov (United States)

    Jacobson, R. A.; Konopliv, A. S.; Park, R. S.; Folkner, W. M.

    2018-03-01

    The International Astronomical Union (IAU) defines planet and satellite coordinate systems relative to their axis of rotation and the angle about that axis. The rotational elements of the bodies are the right ascension and declination of the rotation axis in the International Celestial Reference Frame and the rotation angle, W, measured easterly along the body's equator. The IAU specifies the location of the body's prime meridian by providing a value for W at epoch J2000. We provide new trigonometric series representations of the rotational elements of Mars and its satellites, Phobos and Deimos. The series for Mars are from a least squares fit to the rotation model used to orient the Martian gravity field. The series for the satellites are from a least squares fit to rotation models developed in accordance with IAU conventions from recent ephemerides.

  5. Development of NTD Hydraulic Rotation System for Kijang Research Reactor

    International Nuclear Information System (INIS)

    Kang, Hanok; Park, Kijung; Park, Yongsoo; Kim, Seong Hoon; Park, Cheol

    2014-01-01

    The KJRR will be mainly utilized for isotope production, NTD (Neutron Transmutation Doping) production, and related research activities. During irradiation for the NTD process, the irradiation rigs containing the silicon ingot rotate at a constant speed to ensure precisely defined homogeneity of the irradiation. The NTDHRS requires only hydraulic piping conveniently routed to the rotating devices inside the reactor pool. The resulting layout leaves the pool area clear of obstructions which might obscure vision and hinder target handling for operators. Pump banks and control valves are located remotely in a dedicated plant room allowing easy access and online maintenance. The necessities and major characteristic of NTD hydraulic rotation system are described in this study. A new NTD hydraulic rotation system are being developed to rotate the irradiation rigs at a constant speed and supply cooling flow for the irradiation rigs and reflector assembly. The configuration of the NTD hydraulic rotation device is discussed and practical methods to improve the rotational performance are suggested

  6. Assessing biofuel crop invasiveness: a case study.

    Directory of Open Access Journals (Sweden)

    Christopher Evan Buddenhagen

    Full Text Available BACKGROUND: There is widespread interest in biofuel crops as a solution to the world's energy needs, particularly in light of concerns over greenhouse-gas emissions. Despite reservations about their adverse environmental impacts, no attempt has been made to quantify actual, relative or potential invasiveness of terrestrial biofuel crops at an appropriate regional or international scale, and their planting continues to be largely unregulated. METHODOLOGY/PRINCIPAL FINDINGS: Using a widely accepted weed risk assessment system, we analyzed a comprehensive list of regionally suitable biofuel crops to show that seventy percent have a high risk of becoming invasive versus one-quarter of non-biofuel plant species and are two to four times more likely to establish wild populations locally or be invasive in Hawaii or in other locations with a similar climate. CONCLUSIONS/SIGNIFICANCE: Because of climatic and ecological similarities, predictions of biofuel crop invasiveness in Hawaii are applicable to other vulnerable island and subtropical ecosystems worldwide. We demonstrate the utility of an accessible and scientifically proven risk assessment protocol that allows users to predict if introduced species will become invasive in their region of interest. Other evidence supports the contention that propagule pressure created by extensive plantings will exacerbate invasions, a scenario expected with large-scale biofuel crop cultivation. Proactive measures, such as risk assessments, should be employed to predict invasion risks, which could then be mitigated via implementation of appropriate planting policies and adoption of the "polluter-pays" principle.

  7. Replacing fallow by cover crops: economic sustainability

    Science.gov (United States)

    Gabriel, José Luis; Garrido, Alberto; Quemada, Miguel

    2013-04-01

    Replacing fallow by cover crops in intensive fertilized systems has been demonstrated as an efficient tool for reducing nitrate leaching. However, despite the evident environmental services provided and the range of agronomic benefits documented in the literature, farmers' adoption of this new technology is still limited because they are either unwilling or unable, although adoption reluctance is frequently rooted in low economic profitability, low water se efficiency or poor knowledge. Economic analyses permit a comparison between the profit that farmers obtain from agricultural products and the cost of adopting specific agricultural techniques. The goal of this study was to evaluate the economic impact of replacing the usual winter fallow with cover crops (barley (Hordeum vulgare L., cv. Vanessa), vetch (Vicia villosa L., cv. Vereda) and rapeseed (Brassica napus L., cv. Licapo)) in irrigated maize systems and variable Mediterranean weather conditions using stochastic Monte-Carlo simulations of key farms' financial performance indicators. The three scenarios studied for each cover crop were: i) just leaving the cover crop residue in the ground, ii) leaving the cover crop residue but reduce following maize fertilization according to the N available from the previous cover crop and iii) selling the cover crop residue for animal feeding. All the scenarios were compared with respect to a typical maize-fallow rotation. With observed data from six different years and in various field trials, looking for different weather conditions, probability distribution functions of maize yield, cover crop biomass production and N fertilizer saving was fitted. Based in statistical sources maize grain price, different forage prices and the cost of fertilizer were fitted to probability distribution functions too. As result, introducing a cover crop involved extra costs with respect to fallow as the initial investment, because new seed, herbicide or extra field operations. Additional

  8. A Location Privacy Aware Friend Locator

    DEFF Research Database (Denmark)

    Siksnys, Laurynas; Thomsen, Jeppe Rishede; Saltenis, Simonas

    2009-01-01

    A location-based service called friend-locator notifies a user if the user is geographically close to any of the user’s friends. Services of this kind are getting increasingly popular due to the penetration of GPS in mobile phones, but existing commercial friend-locator services require users...... to trade their location privacy for quality of service, limiting the attractiveness of the services. The challenge is to develop a communication-efficient solution such that (i) it detects proximity between a user and the user’s friends, (ii) any other party is not allowed to infer the location of the user......, and (iii) users have flexible choices of their proximity detection distances. To address this challenge, we develop a client-server solution for proximity detection based on an encrypted, grid-based mapping of locations. Experimental results show that our solution is indeed efficient and scalable...

  9. Developing woody crops for the enhancement of ecosystem services under changing climates in the north central United States

    Science.gov (United States)

    Ronald S. Zalesny; William L. Headlee

    2015-01-01

    Short rotation woody crops belonging to the genera Populus L., Salix L., Pinus L., and Eucalyptus LHer. have provided broad economic and ecological benefits throughout the world, including afforestation and reforestation along urban to rural gradients. Within the genus Populus...

  10. Intensive rainfed and irrigated forage crop production for Mediterranean Italian Buffalo feeding

    Directory of Open Access Journals (Sweden)

    N. Berardo

    2010-02-01

    Full Text Available Buffalo intensive husbandry represents the most lucrative dairy activity in Campania Region. The main forage crop system used in this area are based on winter Italian reygrass (Lolium multiflorum Lam. and spring corn (Zea mays L.. The continuous growing of this crops stressed the soil with a consequent reduction of yield potential. The experiment aimed to assess the agronomic and nutritive feeding value of Italian ryegrasscorn vs other cropping systems (models based on double rotated legumes and graminaceous crops grown under irrigated and rainfed water supply.

  11. The Impact of Volunteer Corn on Crop Yields and Insect Resistance Management Strategies

    Directory of Open Access Journals (Sweden)

    Paul T. Marquardt

    2013-06-01

    Full Text Available Volunteer corn (VC has reemerged as a problematic weed in corn/soybean rotational cropping systems. This reemergence and increasing prevalence of volunteer corn has been correlated to an increased adoption of herbicide-resistant (HR corn hybrids and the adoption of conservation tillage. Since the introduction of HR crops, control options, weed/crop competition, and other concerns (i.e., insect resistance management of Bt traits have increased the amount of attention that volunteer corn is receiving. The objective of this review is to discuss what is known about VC prior to and after the introduction of HR crops, and to discuss new information about this important weed.

  12. Plant biotechnology: transgenic crops.

    Science.gov (United States)

    Shewry, Peter R; Jones, Huw D; Halford, Nigel G

    2008-01-01

    Transgenesis is an important adjunct to classical plant breeding, in that it allows the targeted manipulation of specific characters using genes from a range of sources. The current status of crop transformation is reviewed, including methods of gene transfer, the selection of transformed plants and control of transgene expression. The application of genetic modification technology to specific traits is then discussed, including input traits relating to crop production (herbicide tolerance and resistance to insects, pathogens and abiotic stresses) and output traits relating to the composition and quality of the harvested organs. The latter include improving the nutritional quality for consumers as well as the improvement of functional properties for food processing.

  13. Rotatable seal assembly. [Patent application; rotating targets

    Science.gov (United States)

    Logan, C.M.; Garibaldi, J.L.

    1980-11-12

    An assembly is provided for rotatably supporting a rotor on a stator so that vacuum chambers in the rotor and stator remain in communication while the chambers are sealed from ambient air, which enables the use of a ball bearing or the like to support most of the weight of the rotor. The apparatus includes a seal device mounted on the rotor to rotate therewith, but shiftable in position on the rotor while being sealed to the rotor as by an O-ring. The seal device has a flat face that is biased towards a flat face on the stator, and pressurized air is pumped between the faces to prevent contact between them while spacing them a small distance apart to avoid the inflow of large amounts of air between the faces and into the vacuum chambers.

  14. Cover crops support ecological intensification of arable cropping systems

    Science.gov (United States)

    Wittwer, Raphaël A.; Dorn, Brigitte; Jossi, Werner; van der Heijden, Marcel G. A.

    2017-02-01

    A major challenge for agriculture is to enhance productivity with minimum impact on the environment. Several studies indicate that cover crops could replace anthropogenic inputs and enhance crop productivity. However, so far, it is unclear if cover crop effects vary between different cropping systems, and direct comparisons among major arable production systems are rare. Here we compared the short-term effects of various cover crops on crop yield, nitrogen uptake, and weed infestation in four arable production systems (conventional cropping with intensive tillage and no-tillage; organic cropping with intensive tillage and reduced tillage). We hypothesized that cover cropping effects increase with decreasing management intensity. Our study demonstrated that cover crop effects on crop yield were highest in the organic system with reduced tillage (+24%), intermediate in the organic system with tillage (+13%) and in the conventional system with no tillage (+8%) and lowest in the conventional system with tillage (+2%). Our results indicate that cover crops are essential to maintaining a certain yield level when soil tillage intensity is reduced (e.g. under conservation agriculture), or when production is converted to organic agriculture. Thus, the inclusion of cover crops provides additional opportunities to increase the yield of lower intensity production systems and contribute to ecological intensification.

  15. A rotating quantum vacuum

    Energy Technology Data Exchange (ETDEWEB)

    Lorenci, V.A. de; Svaiter, N.F. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)

    1996-11-01

    It was investigated which mapping has to be used to compare measurements made in a rotating frame to those made in an inertial frame. Using a non-Galilean coordinate transformation, the creation-annihilation operators of a massive scalar field in the rotating frame are not the same as those of an inertial observer. This leads to a new vacuum state(a rotating vacuum) which is a superposition of positive and negative frequency Minkowski particles. Polarization effects in circular accelerators in the proper frame of the electron making a connection with the inertial frame point of view were analysed. 65 refs.

  16. Modelling of the transfer of CS-137 from air to crops, milk, beef and human body following the Chernobyl accident, in a location in Central Bohemia. Test of the model PRYMA T1; Modelizacion de la transferencia de CS-137 desde el aire a las cosechas, la leche, la carne de vacuno y el cuerpo humano producido por el accidente de Chernobyl, en una localizacion en la Bohemia Central. Test del modelo PRYMA T1

    Energy Technology Data Exchange (ETDEWEB)

    Carrasco, E.; Garcia-Olivares, A.; Suaez, A.; Robles, B. Simon, I.; Cancio, D.

    1994-07-01

    This work was made in the frame of the research programme on validation of models for the transfer of radionuclides in the terrestrial, urban and aquatic environments. The acronym of this programme is VAMP (Validation of Model Predictions) and is coordinated by the International Atomic Energy Agency (IAEA) and the Commission of the European Communities (CEC). The scenario was named CB and was presented by the Multiple Pathway Working group. The scenario description was at the beginning a blind test, that is without knowing the location or the measured concentrations and doses. The input information included data of contamination in Cs-137 from the Chernobyl accident in Central Europe, in air and soils and more description of the scenario (data about crops, cattele, demography, human diet, etc.). The aim of the exercise was the contrast between model results and between observed data and model predictions. In this work the results obtained by the CIEMAT-IMA group of modelers are shown and discussed.

  17. Carbon contributions from roots in cotton based rotations

    Science.gov (United States)

    Tan, D. K. Y.; Hulugalle, N. R.

    2012-04-01

    Most research on the decline in soil organic carbon (SOC) stocks in Australian cotton farming systems has focussed on the inputs from above-ground crop residues, with contribution from roots being less studied. This paper aims to outline the contribution of cotton roots and roots of other crops to soil carbon stocks in furrow-irrigated Vertisols in several cotton (Gossypium hirsutum L.)-based rotations. Data was collected from cotton-based rotation systems: cotton monoculture, cotton-vetch (Vicia benghalensis) Roth.), cotton-wheat (Triticum aestivum L.), cotton-wheat-vetch, cotton-corn, corn-corn, cotton-sorghum (Sorghum bicolor L.) and from BollgardTM II (Bt) and non-Bt cotton. Land management systems were permanent beds, with or without standing stubble, and conventional tillage. Root growth in the surface 0.10 m was measured with the core-break method, and that in the 0.10 to 1.0 m depth with a minirhizotron and I-CAP image capture system. These measurements were used to derive root C added to soil through intra-seasonal root death (Clost), C in roots remaining at the end of season (Croot), and total root C added to soil (Ctotal = Croot + Clost). Ctotal in non-Bt cotton (Sicot 80RRF, 0.9 t C/ha/year) was higher than in Bt cotton (Sicot 80RRF, 0.6 t C/ha/year). Overall, Ctotal from cotton roots ranges between 0.5 to 5 t C/ha/year, with Clost contributing 25-70%. Ctotal was greater with vetch than with wheat and was in the order of vetch in cotton-wheat-vetch (5.1 t C/ha/year) > vetch in cotton-vetch (1.9 t C/ha/year) > wheat in cotton-wheat (1.6 t C/ha/year) = wheat in cotton-wheat-vetch (1.7 t C/ha/year). Intra-seasonal root mortality accounted for 12% of total root carbon in vetch and 36% in wheat. Average corn Ctotal with monoculture was 9.3 t/ha and with cotton-corn 5.0 t/ha. Ctotal averaged between both treatments was, thus, of the order of 7.7 t C/ha/year and average Clost 0.04 t/ha/yr. Sorghum roots contributed less carbon with conventional tillage (8.2 t

  18. Biotechnology Towards Energy Crops.

    Science.gov (United States)

    Margaritopoulou, Theoni; Roka, Loukia; Alexopoulou, Efi; Christou, Myrsini; Rigas, Stamatis; Haralampidis, Kosmas; Milioni, Dimitra

    2016-03-01

    New crops are gradually establishing along with cultivation systems to reduce reliance on depleting fossil fuel reserves and sustain better adaptation to climate change. These biological assets could be efficiently exploited as bioenergy feedstocks. Bioenergy crops are versatile renewable sources with the potential to alternatively contribute on a daily basis towards the coverage of modern society's energy demands. Biotechnology may facilitate the breeding of elite energy crop genotypes, better suited for bio-processing and subsequent use that will improve efficiency, further reduce costs, and enhance the environmental benefits of biofuels. Innovative molecular techniques may improve a broad range of important features including biomass yield, product quality and resistance to biotic factors like pests or microbial diseases or environmental cues such as drought, salinity, freezing injury or heat shock. The current review intends to assess the capacity of biotechnological applications to develop a beneficial bioenergy pipeline extending from feedstock development to sustainable biofuel production and provide examples of the current state of the art on future energy crops.

  19. Transpiration and crop yields

    NARCIS (Netherlands)

    Wit, de C.T.

    1958-01-01

    Theoretical and practical aspects of the transpiration of crops in the field are discussed and he concludes that the relationship between transpiration and total dry matter production is much less affected by growing conditions than has been supposed. In semi-arid and arid regions, this relationship

  20. Organic crop breeding

    NARCIS (Netherlands)

    Lammerts Van Bueren, E.; Myers, J.R.

    2012-01-01

    This book provides readers with a thorough review of the latest efforts by crop breeders and geneticists to develop improved varieties for organic production. The book opens with chapters looking at breeding efforts that focus on specific valuable traits such as quality, pest and disease resistance

  1. Crop yields in intercropping

    NARCIS (Netherlands)

    Yu, Y.

    2016-01-01

    Abstract

    Intercropping, the cultivation of two or more crop species simultaneously in the same field, has been widely practiced by smallholder farmers in developing countries and is gaining increasing interest in developed countries. Intercropping can increase the yield per unit

  2. Woody crops conference 2013; Agrarholz-Kongress 2013

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-06-01

    Within the Guelzow expert discussions at 19th and 20th February 2013 in Berlin (Federal Republic of Germany) the following lectures were held: (1) Research funding of the BMELV in the field of the production of woody crops (Andreas Schuette); (2) ELKE - Development of extensive concepts of land use for the production of renewable raw materials as possible compensatory measures and substitute measures (Frank Wegener); (3) Knowledge transfer to the realm of practice, experiences of the DLG (Frank Setzer); (4) Results of the tests with fast growing tree species after 18 years of cultivation in Guelzow (Andreas Gurgel); (5) Latest findings on the production of woody crops in Brandenburg (D. Murach); (6) Phytosanitary situation in short-rotation coppices in Germany - Current state of knowledge and prognoses for the future (Christiane Helbig); (7) Evaluation of alternative delivery procedures in short-rotation coppices (Janine Schweier); (8) With a short-rotation coppice shredder through Germany (Wolfram Kudlich); (9) Changes of land-use of traditional crops rotation systems to short-rotation coppices consisting of poplar trees and willow trees, which sites are suitable? - Selected results from the ProLoc association (Martin Hofmann); (10) Cultivation of populus tremula for short-rotation coppices at agricultural areas (Mirko Liesebach); (11) Investigations of the resistance behaviour of newly developed black poplar clones and balsam poplar clones against the poplar leave rust Melampsora larici-populina (Christina Fey-Wagner); (12) A agri-forestry system for ligneous energy production in the organic farming - First results from cultivation experiments in Bavaria (Klaus Wiesinger); (13) Implementation of agri-forestry systems with energy wood in the rural area - the project AgroForstEnergie (Armin Vetter); (14) Impact of agroforestry land utilization on microclimate, soil fertility and quality of water (Christian Boehm).

  3. Diversified cropping systems support greater microbial cycling and retention of carbon and nitrogen

    Energy Technology Data Exchange (ETDEWEB)

    King, Alison E.; Hofmockel, Kirsten S.

    2017-03-01

    Diversifying biologically simple cropping systems often entails altering other management practices, such as tillage regime or nitrogen (N) source. We hypothesized that the interaction of crop rotation, N source, and tillage in diversified cropping systems would promote microbially-mediated soil C and N cycling while attenuating inorganic N pools. We studied a cropping systems trial in its 10th year in Iowa, USA, which tested a 2-yr cropping system of corn (Zea mays L.)/soybean [Glycine max (L.) Merr.] managed with conventional fertilizer N inputs and conservation tillage, a 3-yr cropping system of corn/soybean/small grain + red clover (Trifolium pratense L.), and a 4-yr cropping system of corn/soybean/small grain + alfalfa (Medicago sativa L.)/alfalfa. Three year and 4-yr cropping systems were managed with composted manure, reduced N fertilizer inputs, and periodic moldboard ploughing. We assayed soil microbial biomass carbon (MBC) and N (MBN), soil extractable NH4 and NO3, gross proteolytic activity of native soil, and potential activity of six hydrolytic enzymes eight times during the growing season. At the 0-20cm depth, native protease activity in the 4-yr cropping system was greater than in the 2-yr cropping system by a factor of 7.9, whereas dissolved inorganic N pools did not differ between cropping systems (P = 0.292). At the 0-20cm depth, MBC and MBN the 4-yr cropping system exceeded those in the 2-yr cropping system by factors of 1.51 and 1.57. Our findings suggest that diversified crop cropping systems, even when periodically moldboard ploughed, support higher levels of microbial biomass, greater production of bioavailable N from SOM, and a deeper microbially active layer than less diverse cropping systems.

  4. On Averaging Rotations

    DEFF Research Database (Denmark)

    Gramkow, Claus

    2001-01-01

    In this paper two common approaches to averaging rotations are compared to a more advanced approach based on a Riemannian metric. Very often the barycenter of the quaternions or matrices that represent the rotations are used as an estimate of the mean. These methods neglect that rotations belong...... to a non-linear manifold and re-normalization or orthogonalization must be applied to obtain proper rotations. These latter steps have been viewed as ad hoc corrections for the errors introduced by assuming a vector space. The article shows that the two approximative methods can be derived from natural...... approximations to the Riemannian metric, and that the subsequent corrections are inherent in the least squares estimation....

  5. Soil and Crop management: Lessons from the laboratory biosphere 2002-2004

    Science.gov (United States)

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

    During the years 2002 and 2003, three closed system experiments were carried out in the "Laboratory Biosphere" facility located in Santa Fe, New Mexico. The program involved experimentation with "Hoyt" Soy Beans, USU Apogee Wheat and TU-82-155 sweet potato using a 5.37 m2 soil planting bed which was 30 cm deep. The soil texture, 40% clay, 31% sand and 28% silt (a clay loam), was collected from an organic farm in New Mexico to avoid chemical residues. Soil management practices involved minimal tillage, mulching and returning crop residues to the soil after each experiment. Between experiment #2 and #3, the top 15 cm of the soil was amended using a mix of peat moss, green sand, humates and pumice to improve soil texture, lower soil pH and increase nutrient availability. Soil analyses for all three experiments are presented to show how the soils have changed with time and how the changes relate to crop selection and rotation, soil selection and management, water management and pest control. The experience and information gained from these experiments are being applied to the future design of the Mars On Earth facility.

  6. Robot Grasps Rotating Object

    Science.gov (United States)

    Wilcox, Brian H.; Tso, Kam S.; Litwin, Todd E.; Hayati, Samad A.; Bon, Bruce B.

    1991-01-01

    Experimental robotic system semiautomatically grasps rotating object, stops rotation, and pulls object to rest in fixture. Based on combination of advanced techniques for sensing and control, constructed to test concepts for robotic recapture of spinning artificial satellites. Potential terrestrial applications for technology developed with help of system includes tracking and grasping of industrial parts on conveyor belts, tracking of vehicles and animals, and soft grasping of moving objects in general.

  7. Rotating universe models

    International Nuclear Information System (INIS)

    Tozini, A.V.

    1984-01-01

    A review is made of some properties of the rotating Universe models. Godel's model is identified as a generalized filted model. Some properties of new solutions of the Einstein's equations, which are rotating non-stationary Universe models, are presented and analyzed. These models have the Godel's model as a particular case. Non-stationary cosmological models are found which are a generalization of the Godel's metrics in an analogous way in which Friedmann is to the Einstein's model. (L.C.) [pt

  8. Electromagnetic rotational actuation.

    Energy Technology Data Exchange (ETDEWEB)

    Hogan, Alexander Lee

    2010-08-01

    There are many applications that need a meso-scale rotational actuator. These applications have been left by the wayside because of the lack of actuation at this scale. Sandia National Laboratories has many unique fabrication technologies that could be used to create an electromagnetic actuator at this scale. There are also many designs to be explored. In this internship exploration of the designs and fabrications technologies to find an inexpensive design that can be used for prototyping the electromagnetic rotational actuator.

  9. Cooling for a rotating anode X-ray tube

    Science.gov (United States)

    Smither, Robert K.

    1998-01-01

    A method and apparatus for cooling a rotating anode X-ray tube. An electromagnetic motor is provided to rotate an X-ray anode with cooling passages in the anode. These cooling passages are coupled to a cooling structure located adjacent the electromagnetic motor. A liquid metal fills the passages of the cooling structure and electrical power is provided to the motor to rotate the anode and generate a rotating magnetic field which moves the liquid metal through the cooling passages and cooling structure.

  10. Quantifying the effect of crops surface albedo variability on GHG budgets in a life cycle assessment approach : methodology and results.

    Science.gov (United States)

    Ferlicoq, Morgan; Ceschia, Eric; Brut, Aurore; Tallec, Tiphaine

    2013-04-01

    We tested a new method to estimate the radiative forcing of several crops at the annual and rotation scales, using local measurements data from two ICOS experimental sites. We used jointly 1) the radiative forcing caused by greenhouse gas (GHG) net emissions, calculated by using a Life Cycle Analysis (LCA) approach and in situ measurements (Ceschia et al. 2010), and 2) the radiative forcing caused by rapid changes in surface albedo typical from those ecosystems and resulting from management and crop phenology. The carbon and GHG budgets (GHGB) of 2 crop sites with contrasted management located in South West France (Auradé and Lamasquère sites) was estimated over a complete rotation by combining a classical LCA approach with on site flux measurements. At both sites, carbon inputs (organic fertilisation and seeds), carbon exports (harvest) and net ecosystem production (NEP), measured with the eddy covariance technique, were calculated. The variability of the different terms and their relative contributions to the net ecosystem carbon budget (NECB) were analysed for all site-years, and the effect of management on NECB was assessed. To account for GHG fluxes that were not directly measured on site, we estimated the emissions caused by field operations (EFO) for each site using emission factors from the literature. The EFO were added to the NECB to calculate the total GHGB for a range of cropping systems and management regimes. N2O emissions were or calculated following the IPCC (2007) guidelines, and CH4 emissions were assumed to be negligible compared to other contributions to the net GHGB. Additionally, albedo was calculated continuously using the short wave incident and reflected radiation measurements in the field (0.3-3µm) from CNR1 sensors. Mean annual differences in albedo and deduced radiative forcing from a reference value were then compared for all site-years. Mean annual differences in radiative forcing were then converted in g C equivalent m-2 in order

  11. Crop responses to climatic variation

    DEFF Research Database (Denmark)

    Porter, John R.; Semenov, Mikhail A.

    2005-01-01

    The yield and quality of food crops is central to the well being of humans and is directly affected by climate and weather. Initial studies of climate change on crops focussed on effects of increased carbon dioxide (CO2) level and/or global mean temperature and/or rainfall and nutrition on crop...... production. However, crops can respond nonlinearly to changes in their growing conditions, exhibit threshold responses and are subject to combinations of stress factors that affect their growth, development and yield. Thus, climate variability and changes in the frequency of extreme events are important...... for yield, its stability and quality. In this context, threshold temperatures for crop processes are found not to differ greatly for different crops and are important to define for the major food crops, to assist climate modellers predict the occurrence of crop critical temperatures and their temporal...

  12. Managing the pepper maggot (Diptera: Tephritidae) using perimeter trap cropping.

    Science.gov (United States)

    Boucher, T Jude; Ashley, Richard; Durgy, Robert; Sciabarrasi, Michael; Calderwood, William

    2003-04-01

    A perimeter trap crop barrier of hot cherry peppers, border-row insecticide applications, and a combination of the two management strategies were evaluated to see if they could protect a centrally located main crop of bell peppers from oviposition and infestation by the pepper maggot, Zonosemata electa (Say). In large plots, the main cash crop of bell peppers was protected from the majority of the oviposition and infestation by all three barriers. The combination sprayed/trap crop barrier provided the best protection against both oviposition and infestation and resulted in over 98% pest-free fruit at harvest. Maggots infested only 1.7% of the main crop fruit when protected by a sprayed or unsprayed trap crop barrier, compared with 15.4% in control plots. The perimeter sprayed/trap crop strategy was employed in three commercial fields in 2000 and 2001. The combination barrier resulted in superior insect control and reduced insecticide use at all commercial locations, compared with the same farms' past history or to farms using conventional and integrated pest management (IPM) methods. Economic analysis showed that the technique is more cost effective and profitable than relying on whole-field insecticide applications to control the pepper maggot. Farmer users were surveyed and found the perimeter trap crop technique simple to use, with many hard-to-measure benefits associated with worker protection issues, marketing, personnel/management relations, pest control and the environment. Use of the perimeter trap crop technique as part of an IPM or organic program can help improve crop quality and overall farm profitability, while reducing pesticide use and the possibility of secondary pest outbreaks.

  13. Barriers to implementing climate resilient agricultural strategies: The case of crop diversification in the U.S

    Science.gov (United States)

    Gabrielle E. Roesch-McNally; J.G. Arbuckle; John C. Tyndall

    2018-01-01

    Cropping system diversity can help build greater agroecosystem resilience by suppressing insect, weed, and disease pressures while also mitigating effects of extreme and more variable weather. Despite the potential benefits of cropping systems diversity, few farmers in the US Corn Belt use diverse rotations. This study examines factors that may influence farmers’...

  14. Fate of Clavibacter michiganensis ssp. sepedonicus, the causal organism of bacterial ring rot in potato, in weeds and field crops.

    NARCIS (Netherlands)

    Wolf, van der J.M.; Beckhoven, van J.R.C.M.; Hukkanen, A.; Karjalainen, R.; Muller, P.

    2005-01-01

    Crops and weeds were tested for their ability to host Clavibacter michiganensis ssp. sepedonicus (Cms), the causal agent of bacterial ring rot in potato. Ten crops grown in rotation with potato in Europe, namely maize, wheat, barley, oat, bush bean, broad bean, rape, pea and onion and five cultivars

  15. 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

    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...... 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...

  16. Onderzoek Location Based Marketing: Mobile = location = effect

    NARCIS (Netherlands)

    Gisbergen, M.S. van; Huhn, A.E.; Khan, V.J.; Ketelaar, P.E.

    2011-01-01

    Onderzoekers van de NHTV (Internationaa Hoger Onderwijs Breda, Radboud Universiteit, DVJ Insights en Popai Benelux lieten consumenten in een virtuele supermarkt advertenties via de smartphone ontvangen wanneer men langs het geadverteerde product liep. De uitkomsten laten zien dat 'location based

  17. Rotating superconductor magnet for producing rotating lobed magnetic field lines

    Science.gov (United States)

    Hilal, Sadek K.; Sampson, William B.; Leonard, Edward F.

    1978-01-01

    This invention provides a rotating superconductor magnet for producing a rotating lobed magnetic field, comprising a cryostat; a superconducting magnet in the cryostat having a collar for producing a lobed magnetic field having oppositely directed adjacent field lines; rotatable support means for selectively rotating the superconductor magnet; and means for energizing the superconductor magnet.

  18. Genetic perspectives on crop domestication

    OpenAIRE

    Gross, Briana L.; Olsen, Kenneth M.

    2010-01-01

    The process of crop domestication has long been a topic of active research for biologists, anthropologists and others. Genetic data have proved a powerful resource for drawing inferences on questions regarding the geographical origins of crops, the numbers of independent domestication events for a given crop species, the specific molecular changes underlying domestication traits, and the nature of artificial selection during domestication and subsequent crop improvement. We would argue that t...

  19. Governing the GM crop revolution

    OpenAIRE

    Paarlberg, Robert L.

    2000-01-01

    Will developing countries adopt policies that promote the planting of genetically modified (GM) crops, or will they select policies that slow the spread of the GM crop revolution? The evidence so far is mixed. In some prominent countries such as China, policies are in place that encourage the independent development and planting of GM crops. Yet in a number of other equally prominent countries the planting of GM crops is not yet officially approved. The inclination of developing countries to ...

  20. Machine vision for camera-based horticulture crop growth monitoring

    OpenAIRE

    McCarthy, A; Hedley, C; El-Naggar, A

    2017-01-01

    Plant growth and fruiting development monitoring is required for horticulture crop and irrigation management. However, this monitoring is typically manual, labour-intensive and conducted in a limited number of locations in the field which may not represent the whole field. Rapid crop assessment throughout the season can be achieved using machine vision analysis of images captured with cameras. High spatial resolution plant growth and fruiting information can be used for yield estimation and t...

  1. Timing, location and crop species influence the magnitude of amelioration of aluminum toxicity by magnesium Época, localização e espécie vegetal na magnitude do efeito protetor do magnésio contra o alumínio tóxico

    Directory of Open Access Journals (Sweden)

    Ivo Ribeiro Silva

    2009-02-01

    Full Text Available The protective effect of cations, especially Ca and Mg, against aluminum (Al rhizotoxicity has been extensively investigated in the last decades. The mechanisms by which the process occurs are however only beginning to be elucidated. Six experiments were carried out here to characterize the protective effect of Mg application in relation to timing, location and crop specificity: Experiment 1 - Protective effect of Mg compared to Ca; Experiment 2 - Protective effect of Mg on distinct root classes of 15 soybean genotypes; Experiment 3 - Effect of timing of Mg supply on the response of soybean cvs. to Al; Experiment 4 - Investigating whether the Mg protective effect is apoplastic or simplastic using a split-root system; Experiment 5 - Protective effect of Mg supplied in solution or foliar spraying, and Experiment 6 - Protective effect of Mg on Al rhizotoxicity in other crops. It was found that the addition of 50 mmol L-1 Mg to solutions containing toxic Al increased Al tolerance in 15 soybean cultivars. This caused soybean cultivars known as Al-sensitive to behave as if they were tolerant. The protective action of Mg seems to require constant Mg supply in the external medium. Supplying Mg up to 6 h after root exposition to Al was sufficient to maintain normal soybean root growth, but root growth was not recovered by Mg addition 12 h after Al treatments. Mg application to half of the root system not exposed to Al was not sufficient to prevent Al toxicity on the other half exposed to Al without Mg in rooting medium, indicating the existence of an external protection mechanism of Mg. Foliar spraying with Mg also failed to decrease Al toxicity, indicating a possible apoplastic role of Mg. The protective effect of Mg appeared to be soybean-specific since Mg supply did not substantially improve root elongation in sorghum, wheat, corn, cotton, rice, or snap bean when grown in the presence of toxic Al concentrations.O efeito protetor de alguns c

  2. CROPS : high tech agricultural robots

    NARCIS (Netherlands)

    Bontsema, J.; Hemming, J.; Pekkeriet, E.J.

    2014-01-01

    In the EU-funded CROPS (Clever Robots for Crops) project high tech robots are developed for site-specific spraying and selective harvesting of fruit and fruit vegetables. The harvesting robots are being designed to harvest high-value crops such as greenhouse vegetables, fruits in orchards and grapes

  3. Crop Sequence Calculator, v. 3

    Science.gov (United States)

    Producers need to know how to sequence crops to develop sustainable dynamic cropping systems that take advantage of inherent internal resources, such as crop synergism, nutrient cycling, and soil water, and capitalize on external resources, such as weather, markets, and government programs. Version ...

  4. 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.

  5. Cover Crop Species and Management Influence Predatory Arthropods and Predation in an Organically Managed, Reduced-Tillage Cropping System.

    Science.gov (United States)

    Rivers, Ariel N; Mullen, Christina A; Barbercheck, Mary E

    2018-01-29

    Agricultural practices affect arthropod communities and, therefore, have the potential to influence the activities of arthropods. We evaluated the effect of cover crop species and termination timing on the activity of ground-dwelling predatory arthropods in a corn-soybean-wheat rotation in transition to organic production in Pennsylvania, United States. We compared two cover crop treatments: 1) hairy vetch (Vicia villosa Roth) planted together with triticale (×Triticosecale Wittmack) after wheat harvest, and 2) cereal rye (Secale cereale Linnaeus) planted after corn harvest. We terminated the cover crops in the spring with a roller-crimper on three dates (early, middle, and late) based on cover crop phenology and standard practices for cash crop planting in our area. We characterized the ground-dwelling arthropod community using pitfall traps and assessed relative predation using sentinel assays with live greater waxworm larvae (Galleria mellonella Fabricius). The activity density of predatory arthropods was significantly higher in the hairy vetch and triticale treatments than in cereal rye treatments. Hairy vetch and triticale favored the predator groups Araneae, Opiliones, Staphylinidae, and Carabidae. Specific taxa were associated with cover crop condition (e.g., live or dead) and termination dates. Certain variables were positively or negatively associated with the relative predation on sentinel prey, depending on cover crop treatment and stage, including the presence of predatory arthropods and various habitat measurements. Our results suggest that management of a cover crop by roller-crimper at specific times in the growing season affects predator activity density and community composition. Terminating cover crops with a roller-crimper can conserve generalist predators.

  6. 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

    Non-inversion tillage with tine or disc based cultivations prior to crop establishment is the most common way of reducing tillage for arable cropping systems with small grain cereals, oilseed rape and maize in Europe. However, new regulations on pesticide use may hinder further expansion of reduced...... 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...

  7. On the effects of rotation on interstellar molecular line profiles

    International Nuclear Information System (INIS)

    Adelson, L.M.; Chunming Leung

    1988-01-01

    Theoretical models are constructed to study the effects of systematic gas rotation on the emergent profiles of interstellar molecular lines, in particular the effects of optical depth and different velocity laws. Both rotational and radial motions (expansion or contraction) may produce similar asymmetric profiles, but the behaviour of the velocity centroid of the emergent profile over the whole cloud (iso-centroid maps) can be used to distinguish between these motions. Iso-centroid maps can also be used to determine the location and orientation of the rotation axis and of the equatorial axis. For clouds undergoing both radial and rotational motion, the component of the centroid due to the rotational motion can be separated from that due to the radial motion. Information on the form of the rotational velocity law can also be derived. (author)

  8. Salt resistant crop plants

    KAUST Repository

    Roy, Stuart J.

    2014-04-01

    Soil salinity is a major constraint to agriculture. To improve salinity tolerance of crops, various traits can be incorporated, including ion exclusion, osmotic tolerance and tissue tolerance. We review the roles of a range of genes involved in salt tolerance traits. Different tissues and cells are adapted for specific and often diverse function, so it is important to express the genes in specific cell-types and to pyramid a range of traits. Modern biotechnology (marker- assisted selection or genetic engineering) needs to be increasingly used to introduce the correct combination of genes into elite crop cultivars. Importantly, the effects of introduced genes need to be evaluated in the field to determine their effect on salinity tolerance and yield improvement.

  9. Cropping Systems and Climate Change in Humid Subtropical Environments

    Directory of Open Access Journals (Sweden)

    Ixchel M. Hernandez-Ochoa

    2018-02-01

    Full Text Available In the future, climate change will challenge food security by threatening crop production. Humid subtropical regions play an important role in global food security, with crop rotations often including wheat (winter crop and soybean and maize (summer crops. Over the last 30 years, the humid subtropics in the Northern Hemisphere have experienced a stronger warming trend than in the Southern Hemisphere, and the trend is projected to continue throughout the mid- and end of century. Past rainfall trends range, from increases up to 4% per decade in Southeast China to −3% decadal decline in East Australia; a similar trend is projected in the future. Climate change impact studies suggest that by the middle and end of the century, wheat yields may not change, or they will increase up to 17%. Soybean yields will increase between 3% and 41%, while maize yields will increase by 30% or decline by −40%. These wide-ranging climate change impacts are partly due to the region-specific projections, but also due to different global climate models, climate change scenarios, single-model uncertainties, and cropping system assumptions, making it difficult to make conclusions from these impact studies and develop adaptation strategies. Additionally, most of the crop models used in these studies do not include major common stresses in this environment, such as heat, frost, excess water, pests, and diseases. Standard protocols and impact assessments across the humid subtropical regions are needed to understand climate change impacts and prepare for adaptation strategies.

  10. Impacts of crop growth dynamics on soil quality at the regional scale

    Science.gov (United States)

    Gobin, Anne

    2014-05-01

    Agricultural land use and in particular crop growth dynamics can greatly affect soil quality. Both the amount of soil lost from erosion by water and soil organic matter are key indicators for soil quality. The aim was to develop a modelling framework for quantifying the impacts of crop growth dynamics on soil quality at the regional scale with test case Flanders. A framework for modelling the impacts of crop growth on soil erosion and soil organic matter was developed by coupling the dynamic crop cover model REGCROP (Gobin, 2010) to the PESERA soil erosion model (Kirkby et al., 2009) and to the RothC carbon model (Coleman and Jenkinson, 1999). All three models are process-based, spatially distributed and intended as a regional diagnostic tool. A geo-database was constructed covering 10 years of crop rotation in Flanders using the IACS parcel registration (Integrated Administration and Control System). Crop allometric models were developed from variety trials to calculate crop residues for common crops in Flanders and subsequently derive stable organic matter fluxes to the soil. Results indicate that crop growth dynamics and crop rotations influence soil quality for a very large percentage. soil erosion mainly occurs in the southern part of Flanders, where silty to loamy soils and a hilly topography are responsible for soil loss rates of up to 40 t/ha. Parcels under maize, sugar beet and potatoes are most vulnerable to soil erosion. Crop residues of grain maize and winter wheat followed by catch crops contribute most to the total carbon sequestered in agricultural soils. For the same rotations carbon sequestration is highest on clay soils and lowest on sandy soils. This implies that agricultural policies that impact on agricultural land management influence soil quality for a large percentage. The coupled REGCROP-PESERA-ROTHC model allows for quantifying the impact of seasonal and year-to-year crop growth dynamics on soil quality. When coupled to a multi-annual crop

  11. Halophytes as Bioenergy Crops

    Directory of Open Access Journals (Sweden)

    Rita Sharma

    2016-09-01

    Full Text Available Shrinking arable land due to soil salinization and, depleting fresh water resources pose serious worldwide constraints to crop productivity. A vision of using plant feedstock for biofuel production can only be realized if we can identify alternate species that can be grown on saline soils and therefore, would not compete for the resources required for conventional agriculture. Halophytes have remarkable ability to grow under high salinity conditions. They can be irrigated with seawater without compromising their biomass and seed yields making them good alternate candidates as bioenergy crops. Both oil produced from the seeds and the lignocellulosic biomass of halophytes can be utilized for biofuel production. Several researchers across the globe have recognized this potential and assessed several halophytes for their tolerance to salt, seed oil contents and composition of their lignocellulosic biomass. Here, we review current advances and highlight the key species of halophytes analyzed for this purpose. We have critically assessed the challenges and opportunities associated with using halophytes as bioenergy crops.

  12. 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

  13. Rotating positron tomographs revisited

    International Nuclear Information System (INIS)

    Townsend, D.; Defrise, M.; Geissbuhler, A.

    1994-01-01

    We have compared the performance of a PET scanner comprising two rotating arrays of detectors with that of the more conventional stationary-ring design. The same total number of detectors was used in each, and neither scanner had septa. For brain imaging, we find that the noise-equivalent count rate is greater for the rotating arrays by a factor of two. Rotating arrays have a sensitivity profile that peaks in the centre of the field of view, both axially and transaxially. In the transaxial plane, this effect offsets to a certain extent the decrease in the number of photons detected towards the centre of the brain due to self-absorption. We have also compared the performance of a rotating scanner to that of a full-ring scanner with the same number of rings. We find that a full-ring scanner with an axial extent of 16.2 cm (24 rings) is a factor of 3.5 more sensitive than a rotating scanner with 40% of the detectors and the same axial extent. (Author)

  14. Physical robustness of canopy temperature models for crop heat stress simulation across environments and production conditions

    DEFF Research Database (Denmark)

    Webber, Heidi; White, Jeffrey W; Kimball, Bruce

    2018-01-01

    Despite widespread application in studying climate change impacts, most crop models ignore complex interactions among air temperature, crop and soil water status, CO2 concentration and atmospheric conditions that influence crop canopy temperature. The current study extended previous studies...... between modeling approaches. More accurate simulation of heat stress will likely require use of energy balance approaches that consider atmospheric stability conditions....... by evaluating Tc simulations from nine crop models at six locations across environmental and production conditions. Each crop model implemented one of an empirical (EMP), an energy balance assuming neutral stability (EBN) or an energy balance correcting for atmospheric stability conditions (EBSC) approach...

  15. Vibrations of rotating machinery

    CERN Document Server

    Matsushita, Osami; Kanki, Hiroshi; Kobayashi, Masao; Keogh, Patrick

    2017-01-01

    This book opens with an explanation of the vibrations of a single degree-of-freedom (dof) system for all beginners. Subsequently, vibration analysis of multi-dof systems is explained by modal analysis. Mode synthesis modeling is then introduced for system reduction, which aids understanding in a simplified manner of how complicated rotors behave. Rotor balancing techniques are offered for rigid and flexible rotors through several examples. Consideration of gyroscopic influences on the rotordynamics is then provided and vibration evaluation of a rotor-bearing system is emphasized in terms of forward and backward whirl rotor motions through eigenvalue (natural frequency and damping ratio) analysis. In addition to these rotordynamics concerning rotating shaft vibration measured in a stationary reference frame, blade vibrations are analyzed with Coriolis forces expressed in a rotating reference frame. Other phenomena that may be assessed in stationary and rotating reference frames include stability characteristic...

  16. The optical rotator

    DEFF Research Database (Denmark)

    Tandrup, T; Gundersen, Hans Jørgen Gottlieb; Jensen, Eva B. Vedel

    1997-01-01

    further discuss the methods derived from this principle and present two new local volume estimators. The optical rotator benefits from information obtained in all three dimensions in thick sections but avoids over-/ underprojection problems at the extremes of the cell. Using computer-assisted microscopes......The optical rotator is an unbiased, local stereological principle for estimation of cell volume and cell surface area in thick, transparent slabs, The underlying principle was first described in 1993 by Kieu Jensen (T. Microsc. 170, 45-51) who also derived an estimator of length, In this study we...... the extra measurements demand minimal extra effort and make this estimator even more efficient when it comes to estimation of individual cell size than many of the previous local estimators, We demonstrate the principle of the optical rotator in an example (the cells in the dorsal root ganglion of the rat...

  17. BIOGAS PRODUCTION FROM CATCH CROPS

    DEFF Research Database (Denmark)

    Molinuevo-Salces, Beatriz; Larsen, Søren U.; Ahring, Birgitte Kiær

    2014-01-01

    Catch crop cultivation combined with its use for biogas production would increase renewable energy production in the form of methane, without interfering with the production of food and fodder crops. The low biomass yield of catch crops is the main limiting factor for using these crops as co......-substrate in manure-based biogas plants and the profit obtained from the sale of biogas barely compensates for the harvest costs. A new agricultural strategy to harvest catch crops together with the residual straw of the main crop was investigated to increase the biomass and thereby the methane yield per hectare...... biomass. Leaving the straw on the field until harvest of the catch crop in the autumn could benefit biogas production due to the organic matter degradation of the straw taking place on the field during the autumn months. This new agricultural strategy may be a good alternative to achieve economically...

  18. Direct use of phosphate rock to improve crop production in Indonesia

    International Nuclear Information System (INIS)

    Sisworo, E.L.; Rasjid, H.; Sisworo, W.H.; Haryanto; Idris, K.

    2002-01-01

    In Indonesia most of the areas left for producing crops have soils such as Ultisols and Oxisols that are highly weathered, acid and of low fertility. One of the main constraints is their low available P to support food crop production. P inputs such as inorganic fertilizers, organic matter, and phosphate rock (PR) must be applied. Phosphate rock is one of the options for farmers to use as a P-source for food crops. In the frame of the coordinated research program three pot and five field experiments were conducted to determine the agronomic effectiveness of PR for food crops using 32 P isotopic techniques. Crops used in the pot experiments were lowland rice, soybean, and mungbean. One of the pot experiments was a crop rotation simulation where upland rice, soybean, and mungbean were grown in sequence. Two of the field experiments were a crop rotation of upland rice, soybean, and mungbean. In the field experiments, 32 P was used to determine the agronomic effectiveness, whenever possible. In general, the direct application of PR was able to increase plant growth in the pot experiments and crop production in the field experiments. Use of 32 P was a good tool to determine the agronomic effectiveness of PR in the pot and field experiments. (author)

  19. Crop yield response to climate change varies with cropping intensity.

    Science.gov (United States)

    Challinor, Andrew J; Parkes, Ben; Ramirez-Villegas, Julian

    2015-04-01

    Projections of the response of crop yield to climate change at different spatial scales are known to vary. However, understanding of the causes of systematic differences across scale is limited. Here, we hypothesize that heterogeneous cropping intensity is one source of scale dependency. Analysis of observed global data and regional crop modelling demonstrate that areas of high vs. low cropping intensity can have systematically different yields, in both observations and simulations. Analysis of global crop data suggests that heterogeneity in cropping intensity is a likely source of scale dependency for a number of crops across the globe. Further crop modelling and a meta-analysis of projected tropical maize yields are used to assess the implications for climate change assessments. The results show that scale dependency is a potential source of systematic bias. We conclude that spatially comprehensive assessments of climate impacts based on yield alone, without accounting for cropping intensity, are prone to systematic overestimation of climate impacts. The findings therefore suggest a need for greater attention to crop suitability and land use change when assessing the impacts of climate change. © 2015 John Wiley & Sons Ltd.

  20. Law Enforcement Locations

    Data.gov (United States)

    Kansas Data Access and Support Center — Law Enforcement Locations in Kansas Any location where sworn officers of a law enforcement agency are regularly based or stationed. Law enforcement agencies "are...

  1. Appraising manufacturing location

    NARCIS (Netherlands)

    Steenhuis, H.J.; de Bruijn, E.J.

    2002-01-01

    International location of manufacturing activities is an issue for managers of manufacturing companies as well as public policy makers. For managers, the issue is relevant because international locations offer opportunities for lowering costs due to productivity improvements. For governments the

  2. Location | FNLCR Staging

    Science.gov (United States)

    The Frederick National Laboratory for Cancer Research campus is located 50 miles northwest of Washington, D.C., and 50 miles west of Baltimore, Maryland, in Frederick, Maryland. Satellite locations include leased and government facilities extending s

  3. Location, Location, Location: Where Do Location-Based Services Fit into Your Institution's Social Media Mix?

    Science.gov (United States)

    Nekritz, Tim

    2011-01-01

    Foursquare is a location-based social networking service that allows users to share their location with friends. Some college administrators have been thinking about whether and how to take the leap into location-based services, which are also known as geosocial networking services. These platforms, which often incorporate gaming elements like…

  4. Sleeping at work: not all about location, location, location.

    Science.gov (United States)

    Jay, Sarah M; Aisbett, Brad; Sprajcer, Madeline; Ferguson, Sally A

    2015-02-01

    Working arrangements in industries that use non-standard hours sometimes necessitate an 'onsite' workforce where workers sleep in accommodation within or adjacent to the workplace. Of particular relevance to these workers is the widely held (and largely anecdotal) assumption that sleep at home is better than sleep away, particularly when away for work. This narrative review explores the idea that sleep outcomes in these unique work situations are the product of an interaction between numerous factors including timing and duration of breaks, commute length, sleeping environment (noise, movement, vibration, light), circadian phase, demographic factors and familiarity with the sleep location. Based on the data presented in this review, it is our contention that the location of sleep, whilst important, is secondary to other factors such as the timing and duration of sleep periods. We suggest that future research should include measures that allow conceptualisation of other critical factors such as familiarity with the sleeping environment. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. 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

    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 generally lower in the low-input organic rotations than......Organic and conventional farming practices differ in the use of several management strategies, including use of catch crops, green manure, and fertilization, which may influence soil properties, greenhouse gas emissions and productivity of agroecosystems. An 11-yr-old field experiment on a sandy...... conducted in plots with winter wheat. In April 2008, prior to field operations, intact soil cores were collected at two depths (0–5 and 5–10 cm) in plots under winter wheat. Water retention characteristics of each core were determined and used to calculate relative gas diffusivity (DP/Do). Finally, crop...

  6. Molecular mechanisms involved in convergent crop domestication.

    Science.gov (United States)

    Lenser, Teresa; Theißen, Günter

    2013-12-01

    Domestication has helped to understand evolution. We argue that, vice versa, novel insights into evolutionary principles could provide deeper insights into domestication. Molecular analyses have demonstrated that convergent phenotypic evolution is often based on molecular changes in orthologous genes or pathways. Recent studies have revealed that during plant domestication the causal mutations for convergent changes in key traits are likely to be located in particular genes. These insights may contribute to defining candidate genes for genetic improvement during the domestication of new plant species. Such efforts may help to increase the range of arable crops available, thus increasing crop biodiversity and food security to help meet the predicted demands of the continually growing global population under rapidly changing environmental conditions. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Energy crops for biogas plants. Lower Saxony; Energiepflanzen fuer Biogasanlagen. Niedersachsen

    Energy Technology Data Exchange (ETDEWEB)

    Aurbacher, J.; Benke, M.; Formowitz, B. (and others)

    2012-06-15

    In the brochure under consideration the Agency for Renewable Resources (Guelzow-Pruezen, Federal Republic of Germany) reports on the support of the implementation of different plant cultures in structure of plantations and crop rotation systems of companies under consideration of the Federal State Lower Saxony. The main chapters of this brochure are: Crops for the production of biogas; implementation in plantations; ensilage and biogas yields; economy of the cultivation of energy plants.

  8. Agronomic, Energetic and Environmental Aspects of Biomass Energy Crops Suitable for Italian Environments

    Directory of Open Access Journals (Sweden)

    Salvatore L. Cosentino

    2008-06-01

    Full Text Available The review, after a short introduction on the tendencies of the European Community Policy on biomasses, describes the agronomic, energy potential and environmental aspects of biomass crops for energy in relation to the research activity carried out in Italy on this topic, differentiating crops on the basis of the main energy use: biodiesel and bioethanol (which refers to “first generation biofuel”, heat and electricity. Currently, many of the crops for potential energy purposes are food crops (wheat, barley, corn, rapeseed, soybean, sunflower, grain sorghum, sugar beet and their production may be used as biofuel source (bioethanol and biodiesel since their crop management aspects are well known and consequently they are immediately applicable. Other species that could be used, highly productive in biomass, such as herbaceous perennial crops (Arundo donax, Miscanthus spp., cardoon, annual crops (sweet sorghum, short rotation woody crops (SRF have been carefully considered in Italy, but they still exhibit critical aspects related to propagation technique, low-input response, harvest and storage technique, cultivars and mechanization. Crops for food, however, often have negative energetic indices and environmental impacts (carbon sequestration, Life Cycle Assessment, consequent to their low productivity. Conversely, crops which are more productive in biomass, show both a more favourable energy balance and environmental impact.

  9. Agronomic, Energetic and Environmental Aspects of Biomass Energy Crops Suitable for Italian Environments

    Directory of Open Access Journals (Sweden)

    Giuseppina M. D’Agosta

    2011-02-01

    Full Text Available The review, after a short introduction on the tendencies of the European Community Policy on biomasses, describes the agronomic, energy potential and environmental aspects of biomass crops for energy in relation to the research activity carried out in Italy on this topic, differentiating crops on the basis of the main energy use: biodiesel and bioethanol (which refers to “first generation biofuel”, heat and electricity. Currently, many of the crops for potential energy purposes are food crops (wheat, barley, corn, rapeseed, soybean, sunflower, grain sorghum, sugar beet and their production may be used as biofuel source (bioethanol and biodiesel since their crop management aspects are well known and consequently they are immediately applicable. Other species that could be used, highly productive in biomass, such as herbaceous perennial crops (Arundo donax, Miscanthus spp., cardoon, annual crops (sweet sorghum, short rotation woody crops (SRF have been carefully considered in Italy, but they still exhibit critical aspects related to propagation technique, low-input response, harvest and storage technique, cultivars and mechanization. Crops for food, however, often have negative energetic indices and environmental impacts (carbon sequestration, Life Cycle Assessment, consequent to their low productivity. Conversely, crops which are more productive in biomass, show both a more favourable energy balance and environmental impact.

  10. Smartphones as locative media

    CERN Document Server

    Frith, Jordan

    2015-01-01

    Smartphone adoption has surpassed 50% of the population in more than 15 countries, and there are now more than one million mobile applications people can download to their phones. Many of these applications take advantage of smartphones as locative media, which is what allows smartphones to be located in physical space. Applications that take advantage of people's location are called location-based services, and they are the focus of this book. Smartphones as locative media raise important questions about how we understand the complicated relationship between the Internet and physical space

  11. Noise Source Location Optimization

    Directory of Open Access Journals (Sweden)

    Ed O’Keefe

    1994-01-01

    Full Text Available This article describes a method to determine locations of noise sources that minimize modal coupling in complex acoustic volumes. Using the acoustic source scattering capabilities of the boundary element method, predictions are made of mode shape and pressure levels due to various source locations. Combining knowledge of the pressure field with a multivariable function minimization technique, the source location generating minimum pressure levels can be determined. The analysis also allows for an objective comparison of “best/worst” locations. The technique was implemented on a personal computer for the U.S. Space Station, predicting 5–10 dB noise reduction using optimum source locations.

  12. Agricultural innovations for sustainable crop production intensification

    Directory of Open Access Journals (Sweden)

    Michele Pisante

    2012-10-01

    Full Text Available Sustainable crop production intensification should be the first strategic objective of innovative agronomic research for the next 40 years. A range of options exist (often very location specific for farming practices, approaches and technologies that ensure sustainability, while at the same time improving crop production. The main challenge is to encourage farmers in the use of appropriate technologies,  and  to  ensure  that  knowledge  about  sound  production  practices  is  increasingly accepted and applied by farmers. There is a huge, but underutilized potential to link farmers’ local knowledge with science-based innovations, through favourable institutional arrangements.  The same  holds  for  the  design,  implementation  and  monitoring  of  improved  natural  resource management  that  links  community  initiatives  to  external  expertise.  It is also suggested that a comprehensive effort be undertaken to measure different stages of the innovation system, including technological adoption and diffusion at the farm level, and to investigate the impact of agricultural policies on technological change and technical efficiency. This paper provides a brief review of agronomic management practices that support sustainable crop production system and evidence on developments  in the selection of crops and cultivars; describes farming systems for crop which take a predominantly ecosystem approach; discusses the scientific application of ecosystem principles for the management of pest and weed populations; reviews the  improvements in fertilizer and nutrient management that explain productivity growth; describes the benefits and constraints of irrigation technologies; and suggests a way forward. Seven changes in the context for agricultural development are proposed that heighten the need to examine how innovation occurs in the agricultural sector.

  13. Breaking continuous potato cropping with legumes improves soil microbial communities, enzyme activities and tuber yield

    Science.gov (United States)

    Qin, Shuhao; Yeboah, Stephen; Cao, Li; Zhang, Junlian; Shi, Shangli; Liu, Yuhui

    2017-01-01

    This study was conducted to explore the changes in soil microbial populations, enzyme activity, and tuber yield under the rotation sequences of Potato–Common vetch (P–C), Potato–Black medic (P–B) and Potato–Longdong alfalfa (P–L) in a semi–arid area of China. The study also determined the effects of continuous potato cropping (without legumes) on the above mentioned soil properties and yield. The number of bacteria increased significantly (p continuous cropping soils, respectively compared to P–C rotation. The highest fungi/bacteria ratio was found in P–C (0.218), followed by P–L (0.184) and then P–B (0.137) rotation over the different cropping years. In the continuous potato cropping soils, the greatest fungi/bacteria ratio was recorded in the 4–year (0.4067) and 7–year (0.4238) cropping soils and these were significantly higher than 1–year (0.3041), 2–year (0.2545) and 3–year (0.3030) cropping soils. Generally, actinomycetes numbers followed the trend P–L>P–C>P–B. The P–L rotation increased aerobic azotobacters in 2–year (by 26% and 18%) and 4–year (40% and 21%) continuous cropping soils compared to P–C and P–B rotation, respectively. Generally, the highest urease and alkaline phosphate activity, respectively, were observed in P–C (55.77 mg g–1) and (27.71 mg g–1), followed by P–B (50.72 mg mg–1) and (25.64 mg g–1) and then P–L (41.61 mg g–1) and (23.26 mg g–1) rotation. Soil urease, alkaline phosphatase and hydrogen peroxidase activities decreased with increasing years of continuous potato cropping. On average, the P–B rotation significantly increased (p improve soil biology environment, alleviate continuous cropping obstacle and increase potato tuber yield in semi–arid region. PMID:28463981

  14. Rotator Cuff Injuries.

    Science.gov (United States)

    Connors, G. Patrick

    Many baseball players suffer from shoulder injuries related to the rotator cuff muscles. These injuries may be classified as muscular strain, tendonitis or tenosynovitis, and impingement syndrome. Treatment varies from simple rest to surgery, so it is important to be seen by a physician as soon as possible. In order to prevent these injuries, the…

  15. Rotations and angular momentum

    International Nuclear Information System (INIS)

    Nyborg, P.; Froyland, J.

    1979-01-01

    This paper is devoted to the analysis of rotational invariance and the properties of angular momentum in quantum mechanics. In particular, the problem of addition of angular momenta is treated in detail, and tables of Clebsch-Gordan coefficients are included

  16. Rotating turbine blade pyrometer

    Science.gov (United States)

    Buchele, D. R.; Lesco, D. J.

    1974-01-01

    Non-contacting pyrometer system optically measures surface temperature distribution on rotating turbine blade, comprising line-by-line scan via fiber optic probe. Each scan line output is converted to digital signals, temporarily stored in buffer memory, and then processed in minicomputer for display as temperature.

  17. Can planetary nebulae rotate

    International Nuclear Information System (INIS)

    Grinin, V.P.

    1982-01-01

    It is shown that the inclination of spectral lines observed in a number of planetary nebulae when the spectrograph slit is placed along the major axis, which is presently ascribed to nonuniform expansion of the shells, actually may be due to rotation of the nebulae about their minor axes, as Campbell and Moore have suggested in their reports. It is assumed that the rotation of the central star (or, if the core is a binary system, circular motions of gas along quasi-Keplerian orbits) serves as the source of the original rotation of a protoplanetary nebula. The mechanism providing for strengthening of the original rotation in the process of expansion of the shell is the tangential pressure of L/sub α/ radiation due to the anisotropic properties of the medium and radiation field. The dynamic effect produced by them is evidently greatest in the epoch when the optical depth of the nebula in the L/sub c/ continuum becomes on the order of unity in the course of its expansion

  18. Rotational Dynamics with Tracker

    Science.gov (United States)

    Eadkhong, T.; Rajsadorn, R.; Jannual, P.; Danworaphong, S.

    2012-01-01

    We propose the use of Tracker, freeware for video analysis, to analyse the moment of inertia ("I") of a cylindrical plate. Three experiments are performed to validate the proposed method. The first experiment is dedicated to find the linear coefficient of rotational friction ("b") for our system. By omitting the effect of such friction, we derive…

  19. 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

  20. The locating ways of laying pipe manipulator

    Science.gov (United States)

    Wang, Dan; Li, Bin; Lei, DongLiang

    2010-01-01

    The laying pipe manipulator is a new equipment to lay concrete pipe. This kind of manipulator makes the work of laying pipes mechanized and automated. We report here a new laying pipe manipulator. The manipulator has 5 free degrees, and is driven by the hydraulic system. In the paper, one critical question of manipulator is studied: the locating ways of the manipulator to lay concrete pipe. During the process of laying concrete pipe, how to locate the manipulator is realized by the locating system of manipulator. The locating system consists of photoelectric target, laser producer, and computer. According to different construction condition, one or two or three photoelectric targets can be used. During the process of laying concrete pipe, if the interface of pipes are jointed together, and the other segment of pipe deviates from the pipe way, one target can be used, if the angle that the manipulator rotates around the holding pipe's axes is 0°, two targets can be used, three targets can be used at any site. In the paper, according to each locating way, the theory analysis is done. And the mathematical models of the manipulator moving from original position to goal position are obtained by different locating way. And the locating experiment was done. According to the experiment result, the work principle and mathematical models of different locating way was turned out to be well adopted for requirement, the mathematical model of different locating way supplies the basic control theory for the manipulator to lay and joint concrete pipe automatically.