WorldWideScience

Sample records for crop rotation systems

  1. Crop rotations that include legumes and reduced tillage improve the energy efficiency of crop production systems

    Science.gov (United States)

    Modern crop production requires large inputs of energy and these inputs represent a substantial cost. Management practices such as crop rotation and choice of tillage practice influence the energy balance for a production system. Legumes support bacteria that are capable of fixing nitrogen (N). This...

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

    Directory of Open Access Journals (Sweden)

    Strašil Zden?k

    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.

  3. Recycling of crop residues for sustainable crop production in a wheat-peanut rotation system

    International Nuclear Information System (INIS)

    Field experiments were conducted in a sandy soil at west Samalout, Minia, Egypt, from December 1996 to October 1999. The main objectives were (i) to examine long-term effects of applications of crop residues on crop nutrition, yields and soil fertility; (ii) to improve process-level understanding of nutrient flows through the use of isotopic techniques, and (iii) to enhance the efficiency of use of nutrients by a wheat-peanut rotation system. There were four treatments: (i) T1, 15N-labelled (NH4)2SO4, 60 kg N/ha at 9.82% 15N with unlabelled residues; (ii) T2, 15N-labelled wheat residues, 26 kg N/ha at 1.94% 15N a.e, applied at the end of the first season; (iii) T3, to generate unlabelled residues and yield; and (iv) T4, 15N-labelled (NH4)2SO4, 60 kg N/ha at 9.82% 15N atom excess, applied at the beginning of the first season, without residues. The Ndff recoveries during the first season in treatments T1 and T4 were 27% and 26% respectively, while 25% of the 15N remained in the soil for T1 and T4. Thus, the total amounts of 15N accounted for (in plant and soil) were 51% for T1 and 50% for T4. After the second crop, the total 15N recovery was 25% and 13% for T1 and T4, respectively. Application of the crop residues seemed to decrease N losses from the soil. Values for %N derived from labelled residues (%Ndfr) by wheat (T2) were 1.0% and 0.4% during seasons 3 and 5, respectively, while recoveries of %Ndfr by peanut from T2 treatments were 3.7, 4.1 and 0.3 during seasons 2, 4 and 6, respectively. In the following five seasons (peanut-wheat-peanut-wheat-peanut), total 15N recoveries by plant and soil were 67, 54, 34, 25 and 16%, respectively. (author)

  4. 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 the basis of weed biomass was higher in the system with potato. The similarity indices, which express the convergence of floristic composition as well as of the density and biomass of weeds growing in pea fields in the two crop rotation systems compared, were within a broad range (42–86%. The biodiversity of weed communities was more closely correlated to total precipitation than to air temperature.

  5. 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

  6. Grain yield and agronomic traits in soybean according to crop rotation systems

    Directory of Open Access Journals (Sweden)

    Henrique Pereira dos Santos

    2014-09-01

    Full Text Available The effects of crop rotation systems (CRS on soybean yield and agronomic characteristics were evaluated from 1996/1997 to 2010/2011 at Embrapa Trigo, Passo Fundo (RS, Brazil. Four soil management systems (SMS were compared, namely: 1 no tillage, 2 minimum tillage, 3 conventional tillage using a disk plow and a disk harrow, and 4 conventional using a moldboard and a disk harrow - and three CRS: system I (wheat/soybean, system II (wheat/soybean and common vetch/corn or sorghum and system III (wheat/soybean, white oats/soybean and common vetch/corn or sorghum. This is a split-plot, randomized, complete block design with three replications. SMS were assigned in the main plot and CRS systems in the split-plots. This work addressed only data on crop rotation systems. There were no significant differences between the CRS for number of grains per plant, 1,000 grain weight and first pod height in soybean. The crop rotation for a summer, with corn or sorghum, propitiates a higher soybean yield compared with the other systems and monoculture soybean. The combination of conservation systems (no tillage and minimum tillage and CR resulted in a higher soybean yield. The lowest grain yield and grain weight per plant were obtained in monoculture soybean.

  7. The Possibilities at Entering Crop Rotation System of Certain Annual Legume Plants in Antalya

    OpenAIRE

    ÇAKMAKÇI, Sad?k; Semiha ÇEÇEN

    1999-01-01

    The research was done during 1994-95 and 1995-96 planting season with 3 replications in randomized complete block design, in Antalya to find the possibility of entering crop rotation system for the forage yield of 9 annual legume plant species. In this work, common vetch, hungarian vetch, hairy vetch, bitter vetch, field pea, chickling vetch, fenugreek, persian clover and berseem plant species were used. For every plant species plant dry matters obtained during harvesting season and days t...

  8. Influence of crop rotation, intermediate crops, and organic fertilizers on the soil enzymatic activity and humus content in organic farming systems

    Science.gov (United States)

    Marcinkeviciene, A.; Boguzas, V.; Balnyte, S.; Pupaliene, R.; Velicka, R.

    2013-02-01

    The influence of crop rotation systems with different portions of nitrogen-fixing crops, intermediate crops, and organic fertilizers on the enzymatic activity and humus content of soils in organic farming was studied. The highest activity of the urease and invertase enzymes was determined in the soil under the crop rotation with 43% nitrogen-fixing crops and with perennial grasses applied twice per rotation. The application of manure and the growing of intermediate crops for green fertilizers did not provide any significant increase in the content of humus. The activity of urease slightly correlated with the humus content ( r = 0.30 at the significance level of 0.05 and r = 0.39 at the significance level of 0.01).

  9. 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. PMID:26647157

  10. Fungal communities of the rhizosphere and the rhizoplane of yellow lupine in a crop rotation system

    OpenAIRE

    Bo?ena Cwalina-Abroziak; Tomasz P. Kurowski

    2001-01-01

    Fungal community populating the rhizosphere and lhe rhizoplane of yellow lupine Juno and Markiz cultivated in the crop rotation with the 20% and 33% portion of lupine was analyzed. The total fungus number was reduced when the participation of lupine in the crop rotation was established at level 20%. Then the pathogenic fungi were replaced by more frequently appeared saprofitic species representing the following genera: Trichoderma, Paecilomyces and Penicillium. Pathogenic Fusarium were more f...

  11. 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 the rotation; furthermore, a considerable number of lesser-known energy crops such as biomass sorghum (Sorghum spp.), hemp (Cannabis sativa), kenaf (Hibiscus cannabinus), Ethiopian mustard (Brassica carinata) could be expected to lead to even greater benefits according to literature. Therefore, this review aimed at systematizing and reorganizing the existing and fragmentary information on these crops while stressing major knowledge gaps to be urgently investigated. (author)

  12. Fungal communities of the rhizosphere and the rhizoplane of yellow lupine in a crop rotation system

    Directory of Open Access Journals (Sweden)

    Bo?ena Cwalina-Abroziak

    2014-08-01

    Full Text Available Fungal community populating the rhizosphere and lhe rhizoplane of yellow lupine Juno and Markiz cultivated in the crop rotation with the 20% and 33% portion of lupine was analyzed. The total fungus number was reduced when the participation of lupine in the crop rotation was established at level 20%. Then the pathogenic fungi were replaced by more frequently appeared saprofitic species representing the following genera: Trichoderma, Paecilomyces and Penicillium. Pathogenic Fusarium were more frequently isolated from the lupine rhizoplane cultivated in combination with its 33% participation.

  13. Maize response to different straw management and tillage systems under cereal crop rotation

    Directory of Open Access Journals (Sweden)

    A. Biskupski

    2006-06-01

    Full Text Available The aim of this study was to determine the effect of various straw management and tillage systems on the emergence, grain yield and cob characteristics of maize (Zea mays L. under different cereal rotations on two soils (Orthic Luvisols of loamy sand and sandy loam textures. The study was conducted in 1999, 2002 and 2003 in a micro-plot (1x1 m experiment. Concrete walls, 120 cm deep, separated each plot of 1x1 m (five replicates. Straw management systems included: removed straw (RS and left straw (LS in the amount of annual straw yield. The retained straw was chopped and spread by hand. Under each straw management system the three following tillage systems were applied: conventional tillage (CT, reduced tillage (RT, no-tillage (NT with sowing to the uncultivated soil and chemical weed control. Each treatment had five replicates giving a total of sixty micro-plots. The preceding crops of maize were rye, winter wheat or maize, depending on the soil and year. The same maize varieties were used in both soils (Antares in 1999-2000 and Matilda in 2003. There was a tendency towards poorer maize emergence in plots with retained straw compared to removed straw under no-tillage system compared to conventionally tilled system in both soils. The results indicated that the reduced tillage systems in combination with chopped straw can be applied on the studied soils without any significant decrease in maize grain yield.

  14. Crop rotation modelling - A European model intercomparison

    DEFF Research Database (Denmark)

    Kollas, Chris; Kersebaum, Kurt C; Nendel, Claas; Manevski, Kiril; Müller, Christoph; Palosuo, Taru; Armas-Herrera, Cecilia M; Beaudoin, Nicolas; Bindi, Marco; Charfeddine, Monica; Conradt, Tobias; Constantin, Julie; Eitzinger, Josef; Ewert, Frank; Ferrise, Roberto; Gaiser, Thomas; de Cortazar-Atauri, Iñaki Garcia; Giglio, Luisa; Hlavinka, Petr; Hoffmann, Holger; Hoffmann, Munir P; Launay, Marie; Manderscheid, Remy; Mary, Bruno; Mirschel, Wilfried; Moriondo, Marco; Olesen, Jørgen E; Öztürk, Isik; Pacholski, Andras; Ripoche-Wachter, Dominique; Roggero, Pier Paolo; Roncossek, Svenja; Rötter, Reimund P; Ruget, François; Sharif, Behzad; Trnka, Mirek; Ventrella, Domenico; Waha, Katharina; Wegehenkel, Martin; Weigel, Hans-Joachim; Wu, Lianhai

    2015-01-01

    Diversification of crop rotations is considered an option to increase the resilience of European crop production under climate change. So far, however, many crop simulation studies have focused on predicting single crops in separate one-year simulations. Here, we compared the capability of fifteen...... 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......, tillage, residues, intermediate or catch crops). We found that the continuous simulation of multi-year crop rotations yielded results of slightly higher quality compared to the simulation of single years and single crops. Intermediate crops (oilseed radish and grass vegetation) were simulated less...

  15. Recycling of crop-residue N for sustainable production in a maize-groundnut rotation system

    International Nuclear Information System (INIS)

    To investigate the contribution of crop residues to the N-economy of a maize-groundnut rotation, a long-term field experiment was established in February 1997. It consisted of the following treatments: (i) T1 - the recommended rate of chemical fertilizer plus residues, (ii) T2 - the recommended rate of chemical fertilizer without residues, and (iii) T3 - a combination of organic fertilizer (chicken dung), chemical fertilizer, and residues. In order to investigate the possible contribution of residue N to subsequent crops, the first maize crop was labelled with 15N. The first crop was sown in March 1997 and 15N-labelled ammonium sulphate was applied at 60 kg N ha-1 to the T1 and T2 treatments, in microplots within yield plots, to generate labelled maize residues. At the same time, 90 kg N ha-1 unlabelled N fertilizer was applied to provide the locally recommended rate for maize of 150 kg N ha-1. Treatment T3 was included for comparison of yields and appraisal of effects on soil properties. After the first crop was harvested, the labelled aboveground residues in T1 were applied to a different microplot so that the fate of the labelled residue-N could be followed. Groundnut was grown in rotation with maize, and, after each harvest, the labelled aboveground residues in the microplots of T1 and T2 were removed and unlabelled residues were added to T1. Because variability between replicates was high in the treatment T2, the average yields in plots with residues, T1 and T3, in the second and third crop cycles were not significantly different from those without residues. Maize yields were similar in the first and second years

  16. Recycling of crop-residue N for sustainable production in maize-groundnut rotation system

    International Nuclear Information System (INIS)

    To investigate the contribution of crop residues to the N-economy of a maize-groundnut rotation, a long-term field experiment was established in February 1997. It consisted of the following treatments: (i) T1 - the recommended rate of chemical fertilizer plus residues, (ii) T2 - the recommended rate of chemical fertilizer without residues, and (iii) T3 - a combination of organic fertilizer (chicken dung), chemical fertilizer, and residues. In order to investigate the possible contribution of residue N to subsequent crops, the first maize crop was labelled with 15N. The first crop was sown in March 1997 and 15N-labelled ammonium sulphate was applied at 60 kg N ha-1 to the T1 and T2 treatments, in microplots within yield plots, to generate labelled maize residues. At the same time, 90 kg N ha-1 unlabelled N fertilizer was applied to provide the locally recommended rate for maize of 150 kg N ha-1. Treatment T3 was included for comparison of yields and appraisal of effects on soil properties. After the first crop was harvested, the labelled aboveground residues in T1 were applied to a different microplot so that the fate of the labelled residue-N could be followed. Groundnut was grown in rotation with maize, and, after each harvest, the labelled aboveground residues in the microplots of T1 and T2 were removed and unlabelled residues were added to T1. Because variability between replicates was high in the treatment T2, the average yields in plots with residues, T1 and T3, in the second and third crop cycles were not significantly different from those without residues. Maize yields were similar in the first and second years

  17. Crop rotation impact on soil quality

    International Nuclear Information System (INIS)

    Management systems influence soil quality over time. A study was carried out on Van meter farm of the Ohio State University South Centers at Piketon Ohio, USA to evaluate the impact of crop rotations on soil quality from 2002 to 2007. The crop rotations comprised of continuous corn (CC), corn-soybean (CS) and corn-soybean-wheat-cowpea (CSW). Ten soil cores were collected at 0-7.5, 7.5-15, 15-22.5 and 22.5-30 cm, and sieved. The soils were analyzed for total microbial biomass (C/sub mic/), basal respiration (BR) and specific maintenance respiration (qCO/sub 2/) rates as biological quality indicators; total organic carbon (TC), active carbon (AC) and total nitrogen (TN) as chemical quality indicators; and aggregate stability (AS), particulate organic matter (POM) and total porosity (ft) as physical quality parameters at different depths of soil. The inductive additive approach based on the concept of 'higher value of any soil property except ft, a better indicator of soil quality' was used to calculate the biological (SBQ), chemical (SCQ), physical (SPQ) and composite soil quality (SQI) indices. The results showed that crop rotation had significant impact on C/sub mic/, BR, qCO/sub 2/, TC, AC, TN, AS and POM except ft at different depths of soil. The CSW had higher soil quality values than CC and CS. The values of selected soil quality properties under the given crop rotation significantly decreased except ft with increasing soil depth. The SBQ (23%), SCQ (16%), SPQ (7%) and SQI (15%) improved under CSW over time. The results imply that multiple cropping systems could be more effective for maintaining and enhancing soil quality than sole-cropping systems. (author)

  18. 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. The perennial legume rotation was identified as the most beneficial and eco-friendly energy crop rotation by showing an increase in Chum, lower GHG emissions per product and area and positive effects on nitrogen dynamics. However, the absolute magnitude of changes and effects differs between the sites indicating an influence of soil type and local climate on the final performance of the energy crop rotation. Generally, the results showed that the positive effect of a certain crop rotation on particular environmental indicators can have a less beneficial effect on another indicator, making an overall evaluation of the energy crop rotation complicated. The weighing of different environmental indicators finally depends on the environmental priorities, political targets and describes a further challenge.

  19. 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.

  20. Crop rotation modelling - A European model intercomparison

    DEFF Research Database (Denmark)

    Kollas, Chris; Kersebaum, Kurt C

    2015-01-01

    Diversification of crop rotations is considered an option to increase the resilience of European crop production under climate change. So far, however, many crop simulation studies have focused on predicting single crops in separate one-year simulations. Here, we compared the capability of fifteen 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, tillage, residues, intermediate or catch crops). We found that the continuous simulation of multi-year crop rotations yielded results of slightly higher quality compared to the simulation of single years and single crops. Intermediate crops (oilseed radish and grass vegetation) were simulated less 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 of superiority of continuous simulations over single year simulation was caused by (a) insufficiently parameterised crops, which affect the performance of the following crop, and (b) the lack of growth-limiting water and/or nitrogen in the crop rotations under investigation. In order to achieve a sound 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.

  1. Assessment of soil biological quality index (QBS-ar) in different crop rotation systems in paddy soils

    Science.gov (United States)

    Nadimi-Goki, Mandana; Bini, Claudio; haefele, Stephan

    2013-04-01

    New methods, based on soil microarthropods for soil quality evaluation have been proposed by some Authors. Soil microarthropods demonstrated to respond sensitively to land management practices and to be correlated with beneficial soil functions. QBS Index (QBS-ar) is calculated on the basis of microarthropod groups present in a soil sample. Each biological form found in the sample receives a score from 1 to 20 (eco-morphological index, EMI), according to its adaptation to soil environment. The objective of this study was to evaluate the effect of various rotation systems and sampling periods on soil biological quality index, in paddy soils. For the purpose of this study surface soil samples (0-15 cm depth) were collected from different rotation systems (rice-rice-rice, soya-rice-rice, fallow-rice and pea-soya-rice) with three replications, and four sampling times in April (after field preparation), June (after seedling), August (after tillering stage) and October (after rice harvesting). The study area is located in paddy soils of Verona area, Northern Italy. Soil microarthropods from a total of 48 samples were extracted and classified according to the Biological Quality of Soil Index (QBS-ar) method. In addition soil moisture, Cumulative Soil Respiration and pH were measured in each site. More diversity of microarthropod groups was found in June and August sampling times. T-test results between different rotations did not show significant differences while the mean difference between rotation and different sampling times is statistically different. The highest QBS-ar value was found in the fallow-rice rotation in the forth soil sampling time. Similar value was found in soya-rice-rice rotation. Result of linear regression analysis indicated that there is significant correlation between QBS-ar values and Cumulative Soil Respiration. Keywords: soil biological quality index (QBS-ar), Crop Rotation System, paddy soils, Italy

  2. Sequential Decision Rules for Managing Nematodes with Crop Rotations

    OpenAIRE

    Burt, O. R.; Ferris, H.

    1996-01-01

    A dynamic model of nematode populations under a crop rotation that includes both host and nonhost crops is developed and used to conceptualize the problem of economic control. The steady state of the dynamic system is used to devise an approximately optimal decision policy, which is then applied to cyst nematode (Heterodera schachtii) control in a rotation of sugarbeet with nonhost crops. Long-run economic returns from this approximately optimal decision rule are compared with results from so...

  3. Crop rotation modelling - A European model intercomparison

    DEFF Research Database (Denmark)

    Kollas, Chris; Kersebaum, Kurt C; Nendel, Claas; Manevski, Kiril; Müller, Christoph; Palosuo, Taru; Armas-Herrera, Cecilia M; Beaudoin, Nicolas; Bindi, Marco; Charfeddine, Monica; Conradt, Tobias; Constantin, Julie; Eitzinger, Josef; Ewert, Frank; Ferrise, Roberto; Gaiser, Thomas; de Cortazar-Atauri, Iñaki Garcia; Giglio, Luisa; Hlavinka, Petr; Hoffmann, Holger; Hoffmann, Munir P; Launay, Marie; Manderscheid, Remy; Mary, Bruno; Mirschel, Wilfried; Moriondo, Marco; Olesen, Jørgen E; Öztürk, Isik; Pacholski, Andras; Ripoche-Wachter, Dominique; Roggero, Pier Paolo; Roncossek, Svenja; Rötter, Reimund P; Ruget, François; Sharif, Behzad; Trnka, Mirek; Ventrella, Domenico; Waha, Katharina; Wegehenkel, Martin; Weigel, Hans-Joachim; Wu, Lianhai

    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...

  4. The Feasibility of Growing A Rotation System of Certain Annual Forage Legume Crops For Seed and Straw Yield in Fall Season Plantings in Antalya

    OpenAIRE

    AYDINO?LU, Sad?k ÇAKMAKÇI Semiha ÇEÇEN Bilal

    1998-01-01

    The aim of this study was to examine the feasibility of growing five annual forage legume crops in the rotation system with second crops in the province of Antalya. In addition the straw and seed yield of the crops were determined when planted in the fall season. Chicling vetch, field pea, fenugreek, persian clover and berseem were planted. The experiment was conducted in the years 1994-1996 with three replications. The flowering day, seed and straw yield, maturity time and harvesting date ...

  5. 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. PMID:24465657

  6. 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 comparing with that under succession (4.95 and 4.14 MgC ha-1, respectively). No differences between succession X rotation (1st year) and succession X rotation (3rd year) were found for litter. Differences in C stock in litter were found only comparing succession (2.42 MgC ha-1) X rotation (2nd year) (3.44 MgC ha-1). Average values of soil C stocks at depth 0-30cm under succession (67.79 MgC ha-1) and rotation (64.83 MgC ha-1) don't differ among treatments. These values in comparison with other determined for similar soil-climate conditions for soils under native forest (60.83 MgC ha-1) and under conventional tillage (60.68 MgC ha-1) reveals a beneficial effect of ZT in soil C stock. Finally, the C stocks determined for plants and litter, representing only 4.0% and 6.4% of that determined for soil, confirm the relevance of soil as a terrestrial C reservoir. Acknowledgments: The authors express thanks for the financial support and technical facilities receipt from Embrapa Trigo, CEPAGRI/ UNICAMP, and FAEPEX/ UNICAMP. CAPES/GOV.BRAZIL is also acknowledged by Dr. Michele K. C. Walter for the greeted scholarship.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-10-03

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

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

    Directory of Open Access Journals (Sweden)

    Eric W. Triplett

    2012-10-01

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

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

    Science.gov (United States)

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

    2007-07-01

    In this study the influence of different farming systems on microbial community structure was analyzed using soil samples from the DOK long-term field experiment in Switzerland, which comprises organic (BIODYN and BIOORG) and conventional (CONFYM and CONMIN) farming systems as well as an unfertilized control (NOFERT). We examined microbial communities in winter wheat plots at two different points in the crop rotation (after potatoes and after maize). Employing extended polar lipid analysis up to 244 different phospholipid fatty acids (PLFA) and phospholipid ether lipids (PLEL) were detected. Higher concentrations of PLFA and PLEL in BIODYN and BIOORG indicated a significant influence of organic agriculture on microbial biomass. Farmyard manure (FYM) application consistently revealed the strongest, and the preceding crop the weakest, influence on domain-specific biomass, diversity indices and microbial community structures. Esterlinked PLFA from slowly growing bacteria (k-strategists) showed the strongest responses to long-term organic fertilization. Although the highest fungal biomass was found in the two organic systems of the DOK field trial, their contribution to the differentiation of community structures according to the management regime was relatively low. Prokaryotic communities responded most strongly to either conventional or organic farming management. PMID:17442013

  10. 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.

  11. 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

    2014-01-01

    The effects of projected changes in climate and atmospheric CO2 concentration on productivity and nitrogen (N) leaching of characteristic arable and pig farming rotations in Denmark were investigated with the FASSET simulation model. The LARS weather generator was used to provide climatic data for the baseline period (1961–90) and in combination with two regional circulation models (RCM) to generate climatic data under the Intergovernmental Panel on Climate Change (IPCC) A1B emission scenario for four different 20-year time slices (denoted by midpoints 2020, 2040, 2060 and 2080) for two locations in Denmark, differing in soil and climate, and representative of the selected production systems. The CO2 effects were modelled using projected CO2 concentrations for the A1B emission scenario. Crop rotations were irrigated (sandy soil) and unirrigated (sandy loam soil), and all included systems 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 rather than single crops for impact assessments. Potato and sugar beet in arable farming and grain maize in pig farming contributed most to the productivity increase in the future scenarios. The highest productivity was obtained in the arable system on the sandy loam soil, with an increase of 20% on average in 2080 with respect to the baseline. Irrigation and fertilization rates would need to be increased in the future to achieve optimum yields. Growing catch crops reduces N leaching, but current catch crop management might not be sufficient to control the potential increase of leaching and more 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 model

  12. 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. PMID:23673753

  13. Nitrogen cycling in organic farming systems with rotational grass-clover and arable crops

    DEFF Research Database (Denmark)

    Berntsen, Jørgen; Grant, Ruth; Olesen, Jørgen E.; Kristensen, Ib Sillebak; Vinther, Finn Pilgaard; Mølgaard, Jens Peter; Petersen, Bjørn Molt

    2006-01-01

    Organic farming is considered an effective means of reducing nitrogen losses compared with more intensive conventional farming systems. However, under certain conditions, organic farming may also be susceptible to large nitrogen (N) losses. This i especially the case for organic .....

  14. JET SYSTEM OF MIXTURE OF FERTILIZERS AT FERTIGATION IRRIGATION CROP ROTATION OF TOMATOES AND CUCUMBERS FOR CULTIVATION IN THE PROTECTED SOIL IN THE CONDITIONS OF THE ROSTOV REGION

    Directory of Open Access Journals (Sweden)

    Degtyareva K. A.

    2014-04-01

    Full Text Available In this article the scheme of landing of early tomatoes and cucumbers in the climatic conditions of the Rostov region is described; we have also calculated the dose of fertilizers for jet system of mixture at a fertigation irrigation. The conclusion is drawn with a possibility of cultivation crop rotation of tomatoes and cucumbers in not heated greenhouses with application of fertilizers

  15. 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

    2014-01-01

    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 input” system as reference systems. The ‘Slurry’ and ‘Conventional’ rotations received slurry and mineral fertilizer, respectively, whereas the ‘No input’ was unfertilized. The ‘Mulching’ and ‘Biogas’ rotations had one year of grass-clover instead of a faba bean crop. The grass-clover biomass was incorporated in the soil in the ‘Mulching’ rotation and removed and used for biogas production in the ‘Biogas’ rotation (and residues from biogas production were simulated to be returned to the field). A method was suggested for allocating effects of fertility building crops in life cycle assessments. The results showed significantly lower carbon footprint of the crops from the ‘Biogas’ rotation (assuming that biogas replaces fossil gas) whereas the remaining crop rotations had comparable carbon footprints per kg cash crop. The study showed considerable contributions caused by the green manure crop (grass-clover) and highlights the importance of analysing the whole crop rotation and including soil carbon changes when estimating carbon footprints of organic crops especially where green manure crops are included.

  16. Resource use at the cropping system level.

    OpenAIRE

    Struik, P. C.; Bonciarelli, F.

    1997-01-01

    This paper illustrates the basic ideas of good crop rotations, adequate crop husbandry and high resource-use efficiencies and some relevant ecological approaches. The use of special crops to prevent the need of high inputs of crop protectants or to reduce losses of nutrients at the level of the cropping system deserves special attention in research. Examples are given for the ecological control of soil-borne fungi, parasitic weeds, nitrogen loss and other sustainable techniques to increase th...

  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.

  18. Rainfed intensive crop systems

    DEFF Research Database (Denmark)

    Olesen, Jørgen E

    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....

  19. Satellite images reveal patterns in crop rotations with alfalfa

    Science.gov (United States)

    Crops that follow alfalfa in rotation usually benefit from: i) reduced nitrogen (N) requirement from fertilizer or manure; ii) increased yield potential than when following other crops; and iii) reduced weed, insect, and disease pressure. Although benefits of alfalfa in crop rotations often depend o...

  20. Lucratividade e risco de sistemas de manejo de solo e de rotação e sucessão de culturas / Profitability and risk of soil tillage and crop rotation and succession systems

    Scientific Electronic Library Online (English)

    Henrique Pereira dos, Santos; Ivo, Ambrosi; Julio Cesar Barreneche, Lhamby; Cristiano do, Carmo.

    2004-02-01

    Full Text Available Sistemas de rotação e de sucessão de culturas reduzem o nível de risco pela diversificação da produção. De 1994/95 a 1997/98, foram avaliados sistemas de manejo de solo e de rotação e sucessão de culturas, em Passo Fundo, RS. Os tratamentos consistiram em quatro sistemas de manejo de solo - 1) plant [...] io direto, 2) cultivo mínimo, 3) preparo convencional de solo com arado de discos e 4) preparo convencional de solo com arado de aivecas - em três sistemas de rotação e sucessão de culturas: sistema I (trigo/soja), sistema II (trigo/soja e ervilhaca/sorgo ou milho) e sistema III (trigo/soja, ervilhaca/sorgo ou milho e aveia branca/soja). O delineamento experimental foi em blocos ao acaso, com parcelas subdivididas e três repetições. A parcela principal foi constituída pelos sistemas de manejo de solo e as subparcelas pelos sistemas de rotação e sucessão de culturas. Foram aplicados à receita líquida nos sistemas de manejo de solo e de rotação e sucessão de culturas dois tipos de análise: análise da média variância e análise de risco. Pela análise da média variância, foi possível separar o plantio direto e o cultivo mínimo como as melhores alternativas a serem oferecidas ao agricultor, por apresentarem maior lucratividade. Pela análise da dominância estocástica, foi possível separar o plantio direto e a rotação de culturas com dois invernos sem trigo como os tratamentos mais lucrativos e de menor risco. Abstract in english Crop rotation and succession systems lesser the risk level due to diversification of cultivities. Soil tillage and crop rotation and succession systems were assessed in Passo Fundo, RS, Brazil, from 1994/95 to 1997/98. Four soil tillage systems - 1) no-tillage, 2) minimum tillage, 3) conventional ti [...] llage using a disk plow, and 4) conventional tillage using a moldboard plow - and three crop rotation and succession systems [system I (wheat/soybean), system II (wheat/soybean and common vetch/sorghum or corn), and system III (wheat/soybean, common vetch/sorghum or corn, and white oats/soybean)] were compared. An experimental design of randomized blocks with split-plots and three replications was used. The main plot was formed by the soil tillage systems, while the split-plots consisted of the crop rotation and succession systems. Two types of analysis were applied to the net return of soil tillage and crop rotation and succession systems: mean-variance and risk analysis. By the mean-variance analysis, no-tillage and minimum tillage, which presented higher net return, were the best alternatives to be offered to the farmer. By the stochastic dominance analysis, no-tillage and crop rotation with two winters without wheat showed the highest profit and the lowest risk.

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

    Directory of Open Access Journals (Sweden)

    Pouzet André

    2003-05-01

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

  2. How can we improve Mediterranean cropping systems?

    DEFF Research Database (Denmark)

    Benlhabib, O.; Yazar, A.

    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 the tested interventions, incorporation of crop residues coupled with supplementary irrigation showed a significantly positive effect on crop productivity, yield stability and environmental sustainability.

  3. Faba bean in cropping systems

    DEFF Research Database (Denmark)

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

    2010-01-01

    though the global average grain yield has almost doubled during the past 50 years the total area sown to faba beans has declined by 56% over the same period. The season-to-season fluctuations in grain yield of faba bean and the progressive replacement of traditional farming systems, which utilized...... legumes to provide N to maintain soil N fertility, with industrialized, largely cereal-based systems that are heavily reliant upon fossil fuels (=N fertilizers, heavy mechanization) are some of the explanations for this decline in importance. Past studies of faba bean in cropping systems have tended to...... focus on the effect of faba bean as a pre-crop in mainly cereal intensive rotations, whereas similar information on the effect of preceding crops on faba bean is lacking. Faba bean has the highest average reliance on N2 fixation for growth of the major cool season grain legumes. As a consequence the N...

  4. Atributos físicos do solo em sistemas de manejo de solo e de rotação de culturas Soil tillage and crop rotation systems on the soil physical attributes

    Directory of Open Access Journals (Sweden)

    Silvio Tulio Spera

    2009-01-01

    Full Text Available A compreensão e a quantificação do impacto do uso e manejo do solo na qualidade física são fundamentais no desenvolvimento de sistemas agrícolas sustentáveis. Com o objetivo de avaliar o efeito de sistemas de manejo de solo e de rotação de culturas sobre alguns atributos físicos de solo em um experimento instalado em 1985, em Latossolo Vermelho Distrófico típico argiloso, em Passo Fundo (RS, estudou-se a variação desses atributos entre 2001 e 2005. Os tratamentos consistiram de quatro modos de manejo de solo: 1 plantio direto (PD; 2 cultivo mínimo (CM; 3 preparo convencional de solo com arado e grade de discos (PCD e 4 preparo convencional de solo com arado de aivecas e grade de discos (PCA, e três sistemas de rotação de culturas: I (trigo/soja, II (trigo/soja e ervilhaca/milho ou sorgo e III (trigo/soja, aveia branca/soja e ervilhaca/milho ou sorgo. O delineamento experimental foi em blocos completos ao acaso, com parcelas subdivididas e três repetições. A parcela foi constituída pelos sistemas de manejo de solo, e as subparcelas, pelos sistemas de rotação de culturas. Amostras de solo também foram coletadas em um fragmento de floresta subtropical adjacente ao experimento, como testemunha da condição original do solo. Os sistemas de manejo e de rotação de culturas influenciaram os atributos físicos do solo quando comparados entre si e com a condição sob floresta subtropical. Em quatro anos (2001 a 2005 ocorreram alterações significativas nos atributos físicos dos solos entre os distintos tipos de manejo. No sistema PD houve maior densidade de solo e microporosidade em comparação aos demais, principalmente na camada subsuperficial, e os sistemas de rotação de plantas não afetaram positivamente os atributos físicos de solo independentemente do tipo de manejo.Evaluation and quantification of soil use impact on its physical quality are important to achieve sustainable cropping systems. Soil physical attributes were assessed after twenty years of implementation (1985 to 2005 on a typical Dystrophic Red Latosol (Rodic Hapludox located in Passo Fundo, Rio Grande do Sul State, Brazil. Four soil tillage systems were evaluated: 1 no-tillage; 2 minimum tillage; 3 conventional tillage using a disk plow plus disk harrow, and 4 conventional tillage using a moldboard plow plus disk harrow. Three crop rotation systems were evaluated: I (wheat/soybean, II (wheat/soybean and common vetch/corn or sorghum, and III (wheat/soybean, common vetch/corn or sorghum and white oats/soybean. A randomized complete block design, with split-plots and three replicates, was used. The main plots were formed by the soil tillage systems, while split-plots were composed by crop rotation systems. As control, soil samples were collected in a subtropical forest fragment adjacent to the experiment. Soil tillage systems and crop rotation systems influenced soil physical parameters when compared to the samples collected in a fragment of subtropical forest. During four years (2001 to 2005 the physical attributes were altered among different soil tillage management. The no-tillage system (PD presented higher soil bulk density and microporosity in comparison to the other systems, mainly in 0.10 to 0.15 m layer, characterizing high soil compaction levels. Crop systems did not promote favorable changes in physical attributes independent of the type of soil management.

  5. Atributos físicos do solo em sistemas de manejo de solo e de rotação de culturas / Soil tillage and crop rotation systems on the soil physical attributes

    Scientific Electronic Library Online (English)

    Silvio Tulio, Spera; Henrique Pereira dos, Santos; Gilberto Omar, Tomm; Rainoldo Alberto, Kochhann; Alexandre, Ávila.

    Full Text Available A compreensão e a quantificação do impacto do uso e manejo do solo na qualidade física são fundamentais no desenvolvimento de sistemas agrícolas sustentáveis. Com o objetivo de avaliar o efeito de sistemas de manejo de solo e de rotação de culturas sobre alguns atributos físicos de solo em um experi [...] mento instalado em 1985, em Latossolo Vermelho Distrófico típico argiloso, em Passo Fundo (RS), estudou-se a variação desses atributos entre 2001 e 2005. Os tratamentos consistiram de quatro modos de manejo de solo: 1) plantio direto (PD); 2) cultivo mínimo (CM); 3) preparo convencional de solo com arado e grade de discos (PCD) e 4) preparo convencional de solo com arado de aivecas e grade de discos (PCA), e três sistemas de rotação de culturas: I (trigo/soja), II (trigo/soja e ervilhaca/milho ou sorgo) e III (trigo/soja, aveia branca/soja e ervilhaca/milho ou sorgo). O delineamento experimental foi em blocos completos ao acaso, com parcelas subdivididas e três repetições. A parcela foi constituída pelos sistemas de manejo de solo, e as subparcelas, pelos sistemas de rotação de culturas. Amostras de solo também foram coletadas em um fragmento de floresta subtropical adjacente ao experimento, como testemunha da condição original do solo. Os sistemas de manejo e de rotação de culturas influenciaram os atributos físicos do solo quando comparados entre si e com a condição sob floresta subtropical. Em quatro anos (2001 a 2005) ocorreram alterações significativas nos atributos físicos dos solos entre os distintos tipos de manejo. No sistema PD houve maior densidade de solo e microporosidade em comparação aos demais, principalmente na camada subsuperficial, e os sistemas de rotação de plantas não afetaram positivamente os atributos físicos de solo independentemente do tipo de manejo. Abstract in english Evaluation and quantification of soil use impact on its physical quality are important to achieve sustainable cropping systems. Soil physical attributes were assessed after twenty years of implementation (1985 to 2005) on a typical Dystrophic Red Latosol (Rodic Hapludox) located in Passo Fundo, Rio [...] Grande do Sul State, Brazil. Four soil tillage systems were evaluated: 1) no-tillage; 2) minimum tillage; 3) conventional tillage using a disk plow plus disk harrow, and 4) conventional tillage using a moldboard plow plus disk harrow. Three crop rotation systems were evaluated: I (wheat/soybean), II (wheat/soybean and common vetch/corn or sorghum), and III (wheat/soybean, common vetch/corn or sorghum and white oats/soybean). A randomized complete block design, with split-plots and three replicates, was used. The main plots were formed by the soil tillage systems, while split-plots were composed by crop rotation systems. As control, soil samples were collected in a subtropical forest fragment adjacent to the experiment. Soil tillage systems and crop rotation systems influenced soil physical parameters when compared to the samples collected in a fragment of subtropical forest. During four years (2001 to 2005) the physical attributes were altered among different soil tillage management. The no-tillage system (PD) presented higher soil bulk density and microporosity in comparison to the other systems, mainly in 0.10 to 0.15 m layer, characterizing high soil compaction levels. Crop systems did not promote favorable changes in physical attributes independent of the type of soil management.

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

    DEFF Research Database (Denmark)

    Dresbøll, Dorte Bodin; Thorup-Kristensen, Kristian

    2014-01-01

    The benefits of improving nitrogen use efficiency (NUE) in crops are typically studied through the performance of the individual crop. However, in order to increase yields in a sustainable way, improving NUE of the cropping systems must be the aim. We did a model simulation study to investigate how improvement of NUE traits of individual crops affects the succeeding crops and the NUE of the crop rotation. Based on experimental results parameterization was altered for different types of improved ...

  7. Pea yield and its components in different crop rotations

    OpenAIRE

    Seibutis, Vytautas; Deveikyt?, Irena

    2006-01-01

    The effects of the crop rotations (2-4 course) differing in duration on the formation of pea productivity elements and the yield were investigated in stationary field experiments in Dotnuva during 1997-2004. Averaged experimental data showed that the highest pea yield (3.70 t ha-1) was recorded in the three-course crop rotation (sugar beet-spring barley-pea), in the four-course (pea-winter wheat-sugar beet-spring barley) and two-course (pea-winter wheat) crop rotations the grain yield consist...

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

    International Nuclear Information System (INIS)

    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

  9. 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-wheat-soybean-bean-upland rice-bean and 4 corn-bean-corn bean-upland rice-bean. Rice, soybean and corn were sown in November/December and bean and wheat in May/June. For this study, only corn, soybean and wheat were considered. Soil tillage affected corn and wheat yields but did not affect soybean yield. Corn and wheat yields under mouldboard plough were higher than under no-tillage. The differences among no-tillage and the other tillage systems in relation to relative accumulative corn yield decreased as the cultivation period increased. Crop rotations did not affect the crop yields.

  10. Climate protection and energy crops. Potential for greenhouse gas emission reduction through crop rotation and crop planning

    International Nuclear Information System (INIS)

    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.

  11. 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; Chirinda, Ngoni; Hermansen, John Erik

    2014-01-01

    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...... 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. The......-clover) and highlights the importance of analysing the whole crop rotation and including soil carbon changes when estimating carbon footprints of organic crops especially where green manure crops are included....

  12. Maize nitrogen fertilization in two crop rotation systems under no-till / Adubação nitrogenada para o milho em dois sistemas de rotação de culturas sob plantio direto

    Scientific Electronic Library Online (English)

    Maria do Carmo, Lana; Rodrigo Vianei, Czycza; Jean Sérgio, Rosset; Jucenei Fernando, Frandoloso.

    2013-12-01

    Full Text Available Com o objetivo de avaliar o parcelamento de doses de nitrogênio (N), aplicadas na semeadura e em cobertura do milho, com e sem rotação de culturas, em semeadura direta, foi realizado um experimento com seis doses de N na semeadura (0, 20, 30, 40, 50 e 60 kg ha-1), combinadas com três doses em cobert [...] ura (40, 70, 100 kg ha-1) e dois sistemas de manejo: após cinco cultivos de milho e com rotação de culturas (milho+soja+aveia+soja+milho), em delineamento de blocos casualizados, com quatro repetições. O sistema de rotação de culturas proporcionou incremento de aproximadamente 7%, no rendimento de grãos, em relação ao da área sem rotação. O parcelamento da adubação nitrogenada, com doses acima de 39 e 54 kg ha-1, na semeadura, com 70 e 40 kg ha-1, em cobertura, respectivamente, resultou em produtividade superior à obtida com aplicação de 100 kg ha-1, em cobertura. O rendimento de grãos foi maior com o parcelamento da dose de 50 e 70 kg ha-1 de N, na semeadura e cobertura, em comparação com o obtido com o parcelamento de 20 e 100 kg ha-1, na semeadura e cobertura, respectivamente. A dose de 70 kg ha-1 de N em cobertura apresentou maior produtividade de grãos com menor custo, em comparação com os rendimentos e custos verificados em relação às doses de 40 e 100 kg ha-1. Abstract in english The objective of this study was to evaluate split nitrogen (N) fertilization of maize applied in band at sowing and top dressing with and without crop rotation, under no-till. The experiment was conducted with six N rates at sowing (0, 20, 30, 40, 50 and 60 kg ha-1) combined with three rates in top [...] dressing (40, 70, 100 kg ha-1) and two management systems: after five cropping sequences of maize and crop rotation (maize + soybean + oat + soybean + corn) in a randomized block design with four replications. The crop rotation system increased yield in approximately 7% in relation to the area without rotation. The split of nitrogen fertilization, in rates above 39 and 54 kg ha-1 at sowing and 70 and 40 kg ha-1 in top dressing, resulted in yield higher than that obtained with the application of 100 kg ha-1 in top dressing. Grain yield was higher with the rates 50 and 70 kg ha-1 of N compared with that obtained with 20 and 100 kg ha-1 at sowing and top dressing, respectively. The rate 70 kg ha-1 of N resulted in the highest yield at the lowest cost compared with the revenues and costs incurred with the rates 40 and 100 kg ha-1.

  13. 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.; A?, Alexander; Zenone, T.; De Groote, T.; Bergante, S.; Facciotto, G.; Sixto, H.; Ciria Ciria, P.; Weger, J.; Ceulemans, R.

    2015-01-01

    Ro?. 41, JAN 2015 (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: BO - Biophysics Impact factor: 5.901, year: 2014

  14. Grain yield and agronomic traits in soybean according to crop rotation systems / Rendimento de grãos e características agronômicas de soja em função de sistemas de rotação de culturas

    Scientific Electronic Library Online (English)

    Henrique Pereira dos, Santos; Renato Serena, Fontaneli; João, Pires; Evandro Ademir, Lampert; Ana Maria, Vargas; Amauri Colet, Verdi.

    2014-09-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito dos sistemas de rotação de culturas (SRC) sobre o rendimento de grãos e as características agronômicas de soja no período de 1996/1997 a 2010/2011 em Latossolo Vermelho distrófico típico, na Embrapa Trigo, em Passo Fundo, RS. Foram comparados quatro tip [...] os de manejo de solo (TMS): 1) sistema plantio direto (SPD); 2) cultivo mínimo (CM); 3) preparo convencional de solo com arado de discos (PCD); e 4) preparo convencional de solo com arado de aivecas (PCA) e três SRC: sistema I (monocultura de trigo/monocultura de soja); sistema II (trigo/soja e ervilhaca/milho ou sorgo); e III (trigo/soja, aveia branca/soja e ervilhaca/milho ou sorgo). O delineamento experimental foi em blocos completos ao acaso, com parcelas subdivididas e três repetições. A parcela foi constituída pelos TMS, e as subparcelas, pelos SRC. No presente trabalho serão abordados somente os dados sobre sistemas de rotação de culturas. A análise conjunta dos dados obtidos não indicou diferença entre os SRC em relação ao número de grãos por planta, à massa de mil grãos e à altura de inserção das primeiras vagens de soja. A rotação de culturas por um verão utilizando milho ou sorgo propicia maior rendimento de grãos de soja em comparação com os demais sistemas estudados e com a soja em monocultura. A combinação de sistemas conservacionistas (SPD e CM) e SRC favoreceu o maior rendimento de grãos de soja. Os menores rendimentos de grãos e massa de grãos ocorreram em monocultura de soja. Abstract in english The effects of crop rotation systems (CRS) on soybean yield and agronomic characteristics were evaluated from 1996/1997 to 2010/2011 at Embrapa Trigo, Passo Fundo (RS), Brazil. Four soil management systems (SMS) were compared, namely: 1) no tillage, 2) minimum tillage, 3) conventional tillage using [...] a disk plow and a disk harrow, and 4) conventional using a moldboard and a disk harrow - and three CRS: system I (wheat/soybean), system II (wheat/soybean and common vetch/corn or sorghum) and system III (wheat/soybean, white oats/soybean and common vetch/corn or sorghum). This is a split-plot, randomized, complete block design with three replications. SMS were assigned in the main plot and CRS systems in the split-plots. This work addressed only data on crop rotation systems. There were no significant differences between the CRS for number of grains per plant, 1,000 grain weight and first pod height in soybean. The crop rotation for a summer, with corn or sorghum, propitiates a higher soybean yield compared with the other systems and monoculture soybean. The combination of conservation systems (no tillage and minimum tillage) and CR resulted in a higher soybean yield. The lowest grain yield and grain weight per plant were obtained in monoculture soybean.

  15. Nitrogen migration in crop rotations differing in fertilisation

    Directory of Open Access Journals (Sweden)

    Saulius Guzys

    2015-06-01

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

  16. 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)

  17. Faba bean in cropping systems

    DEFF Research Database (Denmark)

    Steen Jensen, Erik; Peoples, Mark B.

    2010-01-01

    The grain legume (pulse) faba bean (Vicia faba L.) is grown world-wide as a protein source for food and feed. At the same time faba bean offers ecosystem services such as renewable inputs of nitrogen (N) into crops and soil via biological N2 fixation, and a diversification of cropping systems. Even though the global average grain yield has almost doubled during the past 50 years the total area sown to faba beans has declined by 56% over the same period. The season-to-season fluctuations in grain yield of faba bean and the progressive replacement of traditional farming systems, which utilized legumes to provide N to maintain soil N fertility, with industrialized, largely cereal-based systems that are heavily reliant upon fossil fuels (=N fertilizers, heavy mechanization) are some of the explanations for this decline in importance. Past studies of faba bean in cropping systems have tended to focus on the effect of faba bean as a pre-crop in mainly cereal intensive rotations, whereas similar information on the effect of preceding crops on faba bean is lacking. Faba bean has the highest average reliance on N2 fixation for growth of the major cool season grain legumes. As a consequence the N benefit for following crops is often high, and several studies have demonstrated substantial savings (up to 100–200 kg N ha?1) in the amount of N fertilizer required to maximize the yield of crops grown after faba bean. There is, however, a requirement to evaluate the potential risks of losses of N from the plant–soil system associated with faba bean cropping via nitrate leaching or emissions of N2O to the atmosphere as a consequence of the rapid mineralization of N from its N-rich residues. It is important to develop improved preventive measures, such as catch crops, intercropping, or no-till technologies, in order to provide farmers with strategies to minimize any possible undesirable effects on the environment that might result from their inclusion of faba bean in cropping system. This needs to be combined with research that can lead to a reduction in the current extent of yield variability, so that faba bean may prove to be a key component of future arable cropping systems where declining supplies and high prices of fossil energy are likely to constrain the affordability and use of fertilizers. This will help address the increasing demand by consumers and governments for agriculture to reduce its impact on the environment and climate through new, more sustainable approaches to food production. The aims of this paper are to review the role of faba bean in global plant production systems, the requirements for optimal faba bean production and to highlight the beneficial effects of faba bean in cropping systems.

  18. Propriedades do solo e sistema radicular do feijoeiro irrigado em rotação de culturas / Soil properties and root system of irrigated common beans in crop rotation

    Scientific Electronic Library Online (English)

    E. B., Wutke; F. B., Arruda; A. L., Fancelli; J. C. V. N. A., Pereira; E., Sakai; M., Fujiwara; G. M. B., Ambrosano.

    2000-09-01

    Full Text Available O crescimento do sistema radicular do feijoeiro irrigado, cultivar IAC-Carioca, sob pivô central, em rotação com pousio, milho, aveia preta, Crotalaria juncea L., guandu (Cajanus cajan (L.) Millsp.) e mucuna preta (Mucuna aterrima), no período não-convencional de cultivo no outono-inverno, foi avali [...] ado de 1993 a 1995, em Latossolo Vermelho eutroférrico típico, em área experimental do Instituto Agronômico, em Ribeirão Preto, São Paulo. A rotação de culturas do feijoeiro com milho e adubos verdes favoreceu a redução da resistência do solo à penetração na camada arável, garantiu a manutenção do teor de matéria orgânica do solo, bem como possibilitou a redução da acidez e o aumento do índice de saturação por bases (V%) em profundidade em relação ao teor inicial. A velocidade de infiltração básica da água no solo foi favorecida pela inclusão da mucuna preta, da Crotalaria juncea L. e do milho, no esquema de rotações. A profundidade efetiva observada do seu sistema radicular foi de 0,35 a 0,40 m. Abstract in english Root system growth of the common bean, variety IAC-Carioca, under center pivot irrigation in rotation with fallow; corn; black oat; sunn hemp (Crotalaria juncea L.); pigeon pea [Cajanus cajan (L.) Millsp.] and velvet bean (Mucuna aterrima) was evaluated during a non-conventional (Autumn - Winter) cu [...] ltivation period, from 1993 to 1995, on a typic Haplorthox soil, at an experimental area of the Instituto Agronômico, in Ribeirão Preto, São Paulo, Brazil. The crop sequences of common bean with corn and green manure reduced the soil resistance to penetration into the ploughed layer; maintained the normal contents of the soil organic matter; reduced acidity and increased the base saturation index in depth, in relation to the initial content. The basic infiltration rate was increased with the inclusion of velvet bean, sunn hemp and corn in the crop sequence. Effective root depth (80% of the total) was around 0.35 to 0.40 m.

  19. Principal factors of fodder crops production process in forage and grain-fodder crops rotations

    International Nuclear Information System (INIS)

    The results of research of energy- and mass-exchange dynamics of fodder crops and agrophytocenoses in intensive fodder and grain fodder crops rotations for various soil fertility are analysed. Elements of water balance regime of mineral nutrition, photosynthetic activity, radiation, productivity index and quality of raw materials are presented

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

    Science.gov (United States)

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

    2016-02-01

    Reducing the carbon footprint and increasing energy use efficiency of crop rotations are the two most important sustainability issues of the modern agriculture. Present study was undertaken to assess economics, energy, and environmental parameters of common diversified crop rotations (maize-tomato, and maize-toria-wheat) vis-a-vis traditional crop rotations like maize-wheat, maize + ginger and rice-wheat of the north-western Himalayan region of India. Results revealed that maize-tomato and maize + ginger crop rotations being on par with each other produced significantly higher system productivity in terms of maize equivalent yield (30.2-36.2 t/ha) than other crop rotations (5.04-7.68 t/ha). But interestingly in terms of energy efficiencies, traditional maize-wheat system (energy efficiency 7.9, human energy profitability of 177.8 and energy profitability of 6.9 MJ/ha) was significantly superior over other systems. Maize + ginger rotation showed greater competitive advantage over other rotations because of less consumption of non-renewable energy resources. Similarly, maize-tomato rotation had ability of the production process to exploit natural resources due to 14-38 % less use of commercial or purchased energy sources over other crop rotations. Vegetable-based crop rotations (maize + ginger and maize-tomato) maintained significantly the least carbon footprint (0.008 and 0.019 kg CO2 eq./kg grain, respectively) and the highest profitability (154,322 and 274,161 Rs./ha net return, respectively) over other crop rotations. As the greatest inputs of energy and carbon across the five crop rotations were nitrogen fertilizer (15-29 % and 17-28 %, respectively), diesel (14-24 % and 8-19 %, respectively) and irrigation (10-27 % and 11-44 %, respectively), therefore, alternative sources like organic farming, conservation agriculture practices, soil and water conservation measures, rain water harvesting etc. should be encouraged to reduce dependency of direct energy and external carbon inputs particularly in sub-Himalayas of India. PMID:26739009

  1. 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

    Scientific Electronic Library Online (English)

    José Carlos, Corrêa; Ravi Datt, Sharma.

    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. Abstract in english 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-cott [...] on; 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.

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

    Science.gov (United States)

    Herrmann, Christiane; Idler, Christine; Heiermann, Monika

    2016-04-01

    Methane production characteristics and chemical composition of 405 silages from 43 different crop species were examined using uniform laboratory methods, with the aim to characterise a wide range of crop feedstocks from energy crop rotations and to identify main parameters that influence biomass quality for biogas production. Methane formation was analysed from chopped and over 90days ensiled crop biomass in batch anaerobic digestion tests without further pre-treatment. Lignin content of crop biomass was found to be the most significant explanatory variable for specific methane yields while the methane content and methane production rates were mainly affected by the content of nitrogen-free extracts and neutral detergent fibre, respectively. The accumulation of butyric acid and alcohols during the ensiling process had significant impact on specific methane yields and methane contents of crop silages. It is proposed that products of silage fermentation should be considered when evaluating crop silages for biogas production. PMID:26836846

  3. 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

    The effects of nitrogen (N) availability related to fertilizer type, catch crop management, and rotation composition on cereal yield and grain N were investigated in four organic and one conventional cropping systems in Denmark using the FASSET model. The four-year rotation studied was: spring...... 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) and...... undersowing catch crops (OF + C + M), a system with manure but without undersowing catch crops (OF ? C + M), and a system without manure and with catch crops (OF + C ? M). A grass-clover green manure was used as N fixing crop in the other organic system with catch crops (OG + C + M). Cuttings of grass...

  4. Soil organic carbon dynamics and crop yield for different crop rotations in a degraded ferruginous tropical soil in a semi-arid region: a simulation approach

    OpenAIRE

    SOLER, C. M. TOJO; BADO, V. B.; Traore, K.; BOSTICK, W. MCNAIR; Jones, J.W.; Hoogenboom, G

    2011-01-01

    In recent years, simulation models have been used as a complementary tool for research and for quantifying soil carbon sequestration under widely varying conditions. This has improved the understanding and prediction of soil organic carbon (SOC) dynamics and crop yield responses to soil and climate conditions and crop management scenarios. The goal of the present study was to estimate the changes in SOC for different cropping systems in West Africa using a simulation model. A crop rotation ex...

  5. Cropping systems modulate the rate and magnitude of soil microbial autotrophic CO2 fixation in soil

    OpenAIRE

    Wu, Xiaohong; Ge, Tida; Wang, Wei; Yuan, Hongzhao; Wegner, Carl-Eric; Zhu, Zhenke; Whiteley, Andrew S.; Wu, Jinshui

    2015-01-01

    The effect of different cropping systems on CO2 fixation by soil microorganisms was studied by comparing soils from three exemplary cropping systems after 10 years of agricultural practice. Studied cropping systems included: continuous cropping of paddy rice (rice-rice), rotation of paddy rice and rapeseed (rice-rapeseed), and rotated cropping of rapeseed and corn (rapeseed-corn). Soils from different cropping systems were incubated with continuous 14C-CO2 labeling for 110 days. The CO2-fixin...

  6. Crop Sequence Economics in Dynamic Cropping Systems

    Science.gov (United States)

    No-till production systems allow more intensified and diversified production in the northern Great Plains; however, this has increased the need for information on improving economic returns through crop sequence selection. Field research was conducted 6 km southwest of Mandan ND to determine the inf...

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

    Science.gov (United States)

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

    2015-08-01

    Biodiversity loss, an important consequence of agricultural intensification, can lead to reductions in agroecosystem functions and services. Increasing crop diversity through rotation may alleviate these negative consequences by restoring positive aboveground-belowground interactions. Positive impacts of aboveground biodiversity on belowground communities and processes have primarily been observed in natural systems. Here, we test for the effects of increased diversity in an agroecosystem, where plant diversity is increased over time through crop rotation. As crop diversity increased from one to five species, distinct soil microbial communities were related to increases in soil aggregation, organic carbon, total nitrogen, microbial activity and decreases in the carbon-to-nitrogen acquiring enzyme activity ratio. This study indicates positive biodiversity-function relationships in agroecosystems, driven by interactions between rotational and microbial diversity. By increasing the quantity, quality and chemical diversity of residues, high diversity rotations can sustain soil biological communities, with positive effects on soil organic matter and soil fertility. PMID:26011743

  8. 7 CFR 205.205 - Crop rotation practice standard.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Crop rotation practice standard. 205.205 Section 205.205 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) ORGANIC...

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

    DEFF Research Database (Denmark)

    Munkholm, Lars Juhl; Heck, R

    2013-01-01

    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 long-term rotation and tillage treatment experiment on a Canadian silt loam soil. Topsoil measurements were carried out for three different rotations: R1, (C–C–C–C) continuous corn (Zea mays L.), R6, (C–C–O(RC), B(RC)) corn, corn, oats (Avena fatua L.) and spring barley (Hordeum vulgare L.) and R8, (C–C–S–S) corn, corn, soybean (Glycine max L.), soybean. A red clover (Trifolium pretense L.) cover crop was under seeded in oats and spring barley in R6. In 2010, first year corn was grown in R6 and R8. The tillage treatments included no tillage, NT and mouldboard ploughing, MP. Topsoil structural quality was visually evaluated in early June and mid October. Minimal disturbed soil cores collected in early June were used for X-ray CT scanning and to quantify water content and porosity. 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 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 for the studied soil.

  10. 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.

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

    DEFF Research Database (Denmark)

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

    2011-01-01

    Two main challenges facing organic arable farming are the supply of nitrogen (N) to the crop and the control of perennial weeds. Nitrate leaching from different organic arable crop rotations was investigated over three consecutive four-year crop rotations in a field experiment at three locations in Denmark (12 years in total). The experimental treatments were: (i) crop rotation, (ii) catch crop and (iii) animal manure. Nitrate leaching was estimated from measured soil nitrate concentration in ce...

  12. Impacts on Water Management and Crop Production of Regional Cropping System Adaptation to Climate Change

    Science.gov (United States)

    Zhong, H.; Sun, L.; Tian, Z.; Liang, Z.; Fischer, G.

    2014-12-01

    China is one of the most populous and fast developing countries, also faces a great pressure on grain production and food security. Multi-cropping system is widely applied in China to fully utilize agro-climatic resources and increase land productivity. As the heat resource keep improving under climate warming, multi-cropping system will also shifting northward, and benefit crop production. But water shortage in North China Plain will constrain the adoption of new multi-cropping system. Effectiveness of multi-cropping system adaptation to climate change will greatly depend on future hydrological change and agriculture water management. So it is necessary to quantitatively express the water demand of different multi-cropping systems under climate change. In this paper, we proposed an integrated climate-cropping system-crops adaptation framework, and specifically focused on: 1) precipitation and hydrological change under future climate change in China; 2) the best multi-cropping system and correspondent crop rotation sequence, and water demand under future agro-climatic resources; 3) attainable crop production with water constraint; and 4) future water management. In order to obtain climate projection and precipitation distribution, global climate change scenario from HADCAM3 is downscaled with regional climate model (PRECIS), historical climate data (1960-1990) was interpolated from more than 700 meteorological observation stations. The regional Agro-ecological Zone (AEZ) model is applied to simulate the best multi-cropping system and crop rotation sequence under projected climate change scenario. Finally, we use the site process-based DSSAT model to estimate attainable crop production and the water deficiency. Our findings indicate that annual land productivity may increase and China can gain benefit from climate change if multi-cropping system would be adopted. This study provides a macro-scale view of agriculture adaptation, and gives suggestions to national agriculture adaptation strategy decisions.

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

    Energy Technology Data Exchange (ETDEWEB)

    Wright, L L; Ranney, J W

    1991-01-01

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

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

    International Nuclear Information System (INIS)

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

  15. Energy balance in rainfed herbaceous crops in a semiarid environment for a 15-year experiment. 2. Impact of crop rotations.

    Science.gov (United States)

    Moreno, M. C.; Moreno, M. M.; Lacasta, C.; Tarquis, A. M.; Meco, R.

    2012-04-01

    Energy balances in agriculture production have been widely studied since the 1970s. Researchers have performed detailed energy balances for different crops and farm management systems all over the world in attempts to assess the efficiency and environmental impact of production systems. This work is part of a larger study assessing the effects of three farming systems (conventional, conservation with zero tillage, and organic) and four barley-based crop rotations (barley followed by fallow [B-F], barley in rotation with vetch for hay production [B-V] or sunflower [B-S], and barley monoculture [B-B]), on the energy balance of crop production under the semi-arid conditions over a 15 year period. However, the present work is focused on the crop rotation effect, so farming systems and years are averaged. Experiments were conducted at "La Higueruela" Experimental Farm (4°26' W, 40°04' N, altitude 450 m) (Spanish National Research Council, Santa Olalla, Toledo, central Spain). The climate is semi-arid Mediterranean, with an average seasonal rainfall of 480 mm irregularly distributed. The rotations were simultaneously duplicated to have all phases of each rotation present every year. Results were expressed with respect to one hectare and year for a complete rotation. The energy balance method used required the identification and quantification of all the inputs and outputs implied, and the conversion to energy values by corresponding coefficients. The parameters considered were (i) energy inputs (EI) (diesel, machines, fertilizers, herbicides, seeds) (ii) energy outputs (EO) (energy in the harvested biomass), (iii) net energy produced (NE) (EI - EO), (iv) the energy output/input ratio (O/I), and (v) energy productivity (EP) (Crop yield/EI). Total EI varied from 6.19 GJ ha-1 year-1 for B-F to 11.7 GJ ha-1 year-1 for B-B, that indicates that the energy requirements of barley monoculture (B-B) are almost double those when a fallow period is included in the rotation. Fertilizer was the main energy input, accounting from 52% in B-V to 62% in B-B. EO increased in the order B-B (19.1 GJ ha-1 year-1) ? B-F B-F > B-S > B-B (2.00), indicating the low energy use efficiency of barley monoculture. Vetch was the most energetically efficient crop (yield/input), a result of the low requirements for producing a unit of vetch hay. EP ranged from 360 kg GJ-1 for B-V to 137 kg GJ-1 for B-B. As conclusions and in terms of energy efficiency, cereal monoculture, independent of the crop management system used, appeared to be an energetically unsustainable practice. However, crop rotations, especially those that include a leguminous crop, increase energy efficiency.

  16. Tracking nitrogen losses in a greenhouse crop rotation experiment in North China using the EU-RotateN simulation model

    International Nuclear Information System (INIS)

    Vegetable production in China is associated with high inputs of nitrogen, posing a risk of losses to the environment. Organic matter mineralisation is a considerable source of nitrogen (N) which is hard to quantify. In a two-year greenhouse cucumber experiment with different N treatments in North China, non-observed pathways of the N cycle were estimated using the EU-RotateN simulation model. EU-RotateN was calibrated against crop dry matter and soil moisture data to predict crop N uptake, soil mineral N contents, N mineralisation and N loss. Crop N uptake (Modelling Efficiencies (ME) between 0.80 and 0.92) and soil mineral N contents in different soil layers (ME between 0.24 and 0.74) were satisfactorily simulated by the model for all N treatments except for the traditional N management. The model predicted high N mineralisation rates and N leaching losses, suggesting that previously published estimates of N leaching for these production systems strongly underestimated the mineralisation of N from organic matter. - The EU-RotateN model can satisfactorily simulate crop N uptake and Nmin dynamics in a typical greenhouse cucumber production system of North China

  17. 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)

    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 15N 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

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

    OpenAIRE

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

    2006-01-01

    Crop rotation is a common means of reducing pathogen populations in soil. Several rotation crops have been shown to reduce soybean cyst nematode (Heterodera glycines) populations, but a comprehensive study of the optimal crops is needed. A greenhouse study was conducted to determine the effect of growth and decomposition of 46 crops on population density of H. glycines. Crops were sown in soil infested with H. glycines. Plants were maintained until 75 days after planting, when the soil was mi...

  19. EFFICIENCY OF FERTILIZATION AND SOIL CULTIVATION IN CROP ROTATION

    Directory of Open Access Journals (Sweden)

    Eva CANDRÁKOVÁ

    2009-03-01

    Full Text Available The experiment with the crop rotation: winter wheat, pea, corn, spring barley and cow-grass were founded in 2001- 2004. We examined the effect of the preceding crop, the soil cultivation and fertilization on yield of grain of the main product. The methods of soil cultivation: tillage to the depth of 0.25 m, to the depth of 0.15 m and cultivation where we used disk tools to the depth of 0.10 m. In the variants of fertilization had been used fertilization of the artificial fertilizer with the balance method and fertilization with the artificial fertilizer with the placement of the remains of the preceding crop. By grain corn were statistically significant yield achieved after the tillage to the depth of 0.25 m and 0.15 m. Spring barley reacted positive on the soil cultivation with disk tools. Yield of the winter wheat and the pea were not statistically significant. Fertilization affected statistically significant on yield of winter wheat. The effect of the artificial fertilizers and the residues of the preceding crop on yield of corn, spring barley and pea did not show statistically significant.

  20. Modeling with Limited Data: The Influence of Crop Rotation and Management on Weed Communities and Crop Yield Loss

    Science.gov (United States)

    Theory and models of crop yield loss from weed competition have lead to decision models to help growers with cost-effective tactical weed management. Weed management decision models are available for multiple-species populations in a single season of several crops. Growers also rely on crop rotation...

  1. 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

    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......–C–S–S) corn, corn, soybean (Glycine max L.), soybean. A red clover (Trifolium pretense L.) cover crop was under seeded in oats and spring barley in R6. In 2010, first year corn was grown in R6 and R8. The tillage treatments included no tillage, NT and mouldboard ploughing, MP. Topsoil structural quality was...... visually evaluated in early June and mid October. Minimal disturbed soil cores collected in early June were used for X-ray CT scanning and to quantify water content and porosity. Soil friability was determined on the soil samples using a drop shatter test. Crop yield was determined and correlated to the...

  2. Rotating Aperture System

    Energy Technology Data Exchange (ETDEWEB)

    Rusnak, Brian (Livermore, CA); Hall, James M. (Livermore, CA); Shen, Stewart (Danville, CA); Wood, Richard L. (Santa Fe, NM)

    2005-01-18

    A rotating aperture system includes a low-pressure vacuum pumping stage with apertures for passage of a deuterium beam. A stator assembly includes holes for passage of the beam. The rotor assembly includes a shaft connected to a deuterium gas cell or a crossflow venturi that has a single aperture on each side that together align with holes every rotation. The rotating apertures are synchronized with the firing of the deuterium beam such that the beam fires through a clear aperture and passes into the Xe gas beam stop. Portions of the rotor are lapped into the stator to improve the sealing surfaces, to prevent rapid escape of the deuterium gas from the gas cell.

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

    Science.gov (United States)

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

    2015-03-01

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

  4. INFLUÊNCIA DE CULTURAS DE INVERNO SOBRE O RENDIMENTO DE GRÃOS DE SOJA CULTIVADA EM SISTEMAS DE ROTAÇÃO DE CULTURAS / INFLUENCE OF WINTER CROPS ON SOYBEAN YIELD IN CROP ROTATION SYSTEMS

    Scientific Electronic Library Online (English)

    Henrique Pereira dos, Santos; Julio Cesar Barreneche, Lhamby.

    2001-02-01

    Full Text Available Durante nove anos, avaliou-se o efeito de diferentes culturas antecessoras sobre o rendimento de grãos e sobre a estatura de plantas de soja, na EMBRAPA-Centro Nacional de Pesquisa de Trigo (CNPT), em Passo Fundo, RS. Os tratamentos consistiram em sete sistemas de rotação de culturas, e a soja foi s [...] emeada em sucessão à aveia branca, à aveia preta, ao linho e ao trigo. Em 1990, foram adicionadas duas parcelas, uma para completar o sistema II e outra para pousio de inverno antecedendo a soja (sistema VII). As culturas de inverno foram estabelecidas com preparo convencional de solo, e as de verão, em plantio direto. O delineamento experimental foi blocos ao acaso, com três repetições, e parcelas com área útil de 30m². A soja cultivada após linho, na média do período de 1987 a 1989, nos sistemas IV e VI, apresentou menor estatura de plantas e menor rendimento de grãos. Nos períodos de 1990 a 1992 e de 1993 a 1995, não houve diferenças significativas entre tipo de cultura antecessora e rendimento de grãos. A soja cultivada após aveia branca, após aveia preta ou após trigo pode ser incluída, sem prejuízo, nos diferentes sistemas estudados. Abstract in english Different preceding crops on the yield and height of soybean plants was assessed during nine years at EMBRAPA-Centro Nacional de Pesquisa de Trigo (CNPT), in Passo Fundo, RS, Brazil. The treatments consisted of seven crop systems, and soybean was sown in succession to white oat, black oat, flax, and [...] wheat. Two plots were added in 1990; one to complement system II and the other as winter fallow preceding soybean (system VII). Winter crops were set up using conventional soil preparation, and summer crops were sown under no-tillage. An experimental design of blocks at random, with three replications and plots totalling 30m², was used. The grown soybean after flax, in the mean of the period 1987 to 1989, in systems IV and VI showed lower plant on height and lower yield. No significant differences were found on the evoluated preceding crops on the yield over the periods 1990 to 1992 and 1993 to 1995. The grown soybean after white oat, black oat or wheat may be included in the different systems studied without any adverse effect.

  5. Influência de rotações de culturas nas propriedades físico-hídricas de um Latossolo Vermelho em plantio direto / Influence of crop rotations on the physical-hydrical properties of an oxisol in no-tillage system

    Scientific Electronic Library Online (English)

    Eurâimi de Q., Cunha; Luiz C., Balbino; Luís F., Stone; Wilson M., Leandro; Geraldo C. de, Oliveira.

    2007-12-01

    Full Text Available A adoção do plantio direto, com a inclusão de espécies gramíneas de relação C/N alta, poderá minimizar a degradação estrutural do solo. O objetivo deste trabalho foi avaliar a influência da inclusão da braquiária na rotação de culturas nas propriedades físico-hídricas e no conteúdo de matéria orgâni [...] ca de um Latossolo Vermelho distrófico em plantio direto. O delineamento experimental foi o de blocos ao acaso, em parcelas subdivididas, com quatro repetições. As parcelas foram compostas por quatro sistemas de rotação, e as subparcelas, por quatro profundidades de amostragem (0-10; 10-20; 20-40, e 40-60 cm). As culturas utilizadas foram: arroz (A); feijão irrigado (F); milho (M); soja (S), e arroz (A+B), milho (M+B) e soja (S+B) consorciados com braquiária. Os sistemas de rotação foram: S1 - A/F/M/F/S/F; S2 - A+B/F/M+B/F/S+B/F; S3 - M/F/S/F/S/F, e S4 - M+B/F/S+B/F/S+B/F. Uma área de mata nativa, situada a 500 m do experimento, foi considerada como controle. A inclusão da braquiária na rotação de culturas não afetou a densidade, a macroporosidade e a capacidade de água disponível do solo. A porosidade total e o teor de matéria orgânica do solo foram favorecidos pelas rotações que incluíam maior número de cultivos de soja. A associação de soja com a braquiária contribuiu para a estabilidade dos agregados, e a de gramíneas de verão com a braquiária, para a diminuição da resistência do solo à penetração. Abstract in english The adoption of no-tillage system, with the inclusion of grass species of high C/N relationship, can minimize the structural degradation of the soil. The objective of this research was to evaluate the influence of including Brachiaria in crop rotation systems on the physical-hydric properties and th [...] e organic matter content in a Dystrophic Oxisol under no-tillage. The experiment was conducted in a randomized block design, in split plots, with four replications. The plots were composed by four systems of crop rotation and the subplots by four sampling depths (0-10; 10-20; 20-40, and 40-60 cm). The crops were: rice (R); irrigated dry bean (DB); corn (C); soybean (S); rice (R+B), corn (C+B), and soybean (S+B) intercropped with Brachiaria. The crop rotation systems were: S1 - R/DB/C/DB/S/DB; S2 - R+B/DB/C+B/DB/S+B/DB; S3 - C/DB/S/DB/S/DB; and S4 - C+B/DB/S+B/DB/S+B/DB. It was considered a native forest, located at 500 m from the experiment, as reference. The inclusion of Brachiaria in crop rotation systems did not affect soil bulk density, macroporosity, and available soil water capacity. Total soil porosity and organic matter content of the soil were favored in the crop rotations that included more number of soybean cultivations. The association of soybean with Brachiaria contributed to the stability of the aggregates and the summer grasses with Brachiaria to reduce the soil resistance to penetration.

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

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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 fuels and in taking pressure off native forests for energy uses provides longer term carbon benefits 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 10 to 40 tonnes per hectare over about a 20 to 50 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 terestrial and atmospheric carbon dynamics. It is speculated that plantations, when viewed in this context, could generate a global levelling of net carbon emissions for approximately 10 to 20 years. 16 refs., 7 figs

  8. The Potato Systems Planner: Integrating Cropping System Impacts on Crop Yield and Quality, Soil Biology, Nutrient Cycling, Diseases, and Economics

    Science.gov (United States)

    Finding and developing profitable cropping systems is a high priority for the potato industry. Consequently, an interdisciplinary team of ARS scientists from the New England Plant, Soil, & Water Laboratory evaluated 14 different rotations for their impacts on crop yield and quality, nutrient availa...

  9. 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.

  10. Rotação de culturas para trigo, após quatro anos: efeitos na fertilidade do solo em plantio direto Crop rotation systems for wheat, after four years: effects on soil fertility under no-tillage

    Directory of Open Access Journals (Sweden)

    Henrique Pereira dos Santos

    1999-06-01

    Full Text Available A fertilidade do solo foi avaliada, após quatro anos (1990 a 1994, num latossolo bruno álico, em Guarapuava, PR, Brasil, em quatro sistemas de rotação de culturas para trigo: sistema I (trigo/soja; sistema II (trigo/soja e aveia branca/soja; sistema III (trigo/soja, ervilhaca/ milho e aveia branca/soja; e sistema IV (trigo/soja, aveia branca/soja, cevada/soja e ervilhaca/ milho. As culturas, tanto de inverno como de verão, foram estabelecidas sob plantio direto. O delineamento experimental foi de blocos ao acaso com quatro repetições. Através de contrastes, foram comparados os sistemas e as profundidades de amostragem de solo. Em todos os sistemas de rotação de culturas, na camada de solo 0 a 5cm, observaram-se valores maiores de pH e de Ca+Mg e menores de Al (com exceção do sistema III, em relação à camada 15 a 20cm. Houve elevação dos teores de Ca+Mg, de K e de P na camada de solo com a maior concentração de raízes (0 a 10cm. Os valores de matéria orgânica do solo decresceram progressivamente da camada 0 a 5cm para a camada 15 a 20cm.Soil fertility parameters were evaluated after four years (1990 to 1994 on a alic dusky latosol located in Guarapuava, Paraná, Brazil, under four wheat crop rotation systems as follows: system I (wheat/soybean; system II (wheat/soybean and white oats/soybean; system III (wheat/soybean, common vetch/corn, and white oats/soybean; and system IV (wheat/soybean, white oats/soybean, barley/soybean and common vetch/cor. Both winter and summer crops were seeded under no tillage. A randomized complete block design, with four replications, was used. Crop systems and soil samples at different depths were compared using the contrast procedure. All crop rotation systems, in the 0 to 5cm soil layer, higher values were observed for pH in water and Ca+Mg and lower contents for Al (except system III, as compared to the 15 to 20cm layer. Raising in Ca+Mg, K, and P levels occurred in the soil layer with the greatest root concentration (0 to 10cm. The soil organic matter contents decreased with depth from 0-5cm to 15-20cm.

  11. Soil water retention and s index after crop rotation and chiseling

    Directory of Open Access Journals (Sweden)

    Juliano Carlos Calonego

    2011-12-01

    Full Text Available Soil compaction can be minimized either mechanically or biologically, using plant species with vigorous root systems. An experiment was carried out with soybean (Glycine max in rotation with triticale (X Triticosecale and sunflower (Helianthus annuus in fall-winter associated with pearl millet (Pennisetum glaucum, grain sorghum (Sorghum bicolor or sunn hemp (Crotalaria juncea in spring. Crop rotation under no-till was compared with mechanical chiseling. The experiment was carried out in Botucatu, São Paulo State, Brazil. Soil quality was estimated using the S index and soil water retention curves (in the layers of 0-0.05, 0.075-0.125, 0.15-0.20, 0.275-0.325, and 0.475-0.525 m deep. Crop rotation and chiseling improved soil quality, increasing the S index to over 0.035 to a depth of 20 cm in the soil profile. The improved soil quality, as shown by the S index, makes the use of mechanical chiseling unnecessary, since after 3 years the soil physical quality under no-tilled crop rotation and chiseling was similar.

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

    OpenAIRE

    Sophan Chhin

    2016-01-01

    Sustainable woody biofeedstock production systems require a reliable supply of woody biomass that could be affected by future climate change. However, there is limited understanding of the climatic sensitivity of short rotation woody crops, such as hybrid aspens. The general objective of this study is to identify climatically resilient hybrid aspen clones for woody biomass feedstock development. Specifically, tree-ring analysis methods (dendrochronology) were used to quantify the influence of...

  13. Long-Term Effects of Rotational Tillage On Visual Evaluation of Soil Structure, Soil Quality and Crop Yield

    DEFF Research Database (Denmark)

    Munkholm, Lars Juhl; Heck, Richard

    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 long term integrated effects tillage and rotation. We studied the issue using a 30 year old long-term rotation and tillage treatment experiment on a Canadian silt loam soil. Measurements were carried out in the topsoil for three different rotations: R1 (C-C-C-C) continuous corn (Zea mays L.), R6. (C-C-O(RC), B(RC)) corn, corn, oats (Avena fatua L.) and spring barley (Hordeum vulgare L.) and R8, (C-C-S-S) corn, corn, soybean (Glycine max L.), soybean. A red clover (Trifolium pretense L.) cover crop was under seeded in oats and spring barley in R6. In 2010, first year corn was grown in R6 and R8. The tillage treatments included no tillage, NT and mouldboard plowing, MP. Topsoil 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 of NT for the studied soil.

  14. Desempenho agronômico da soja sob diferentes rotações e sucessões de culturas em sistema plantio direto / Agronomic performance of soybean in different rotations and successions of crops in no tillage system

    Scientific Electronic Library Online (English)

    Cinthia Raquel, Mancin; Luiz Carlos Ferreira de, Souza; José Oscar, Novelino; Marlene Estevão, Marchetti; Manoel Carlos, Gonçalves.

    2009-03-01

    Full Text Available Este trabalho faz parte de um projeto de longa duração que teve início em 1997 e envolve produção de grãos baseada em sistemas de rotação ou sucessão de culturas. O experimento foi desenvolvido no ano agrícola 2005/06, em LATOSSOLO VERMELHO Distroférrico, na Fazenda Experimental de Ciências Agrárias [...] da Universidade Federal da Grande Dourados - UFGD, em Dourados, Estado de Mato Grosso do Sul. O delineamento experimental foi em blocos casualizados com sete tratamentos e três repetições. Em cada parcela, foram semeadas mecanicamente 26 linhas de soja com 36 m de comprimento, espaçadas entre si por 0,45 m. Os tratamentos consistiram de sete sistemas de rotação ou sucessão, envolvendo espécies semeadas solteiras ou com misturas de espécies antecessoras a soja, constituindo os seguintes tratamentos: Sistema 1: crotalária+ervilhaca/soja; Sistema 2: ervilhaca+aveia+nabo/soja; Sistema 3: girassol/soja; Sistema 4: milheto/soja; Sistema 5: milho/soja; Sistema 6: trigo/soja e Sistema 7: aveia/soja. Foram avaliadas a altura de planta, altura de inserção da primeira vagem, número de ramificações por planta, número de vagens por planta, produtividade da soja, massa de 100 grãos. Concluiu-se que podem ser utilizadas várias espécies em rotação ou sucessão de cultura com a soja no sistema plantio direto consolidado, sem afetar os componentes de produção da leguminosa. Abstract in english This work is a part of a long-term project that began in 1997 and which involves grain production based on crop rotation or crop succession systems. The experiment was carried out in the 2005/06 season, in a Dystroferric Red Latosol, in the Agrarian Science Experimental Farm of Federal University of [...] Great Dourados - UFGD, in Dourados, Mato Grosso do Sul, Brazil. The experimental design was in randomized blocks with seven treatments and three replications. In each parcel, 26 rows of soybean were sowed, 36 m long, spaced 0.45 m apart. Treatments consisted of seven systems of rotation or succession, involving species that were sowed alone or mixed with species that preceded soybean, comprising the following treatments: System 1: crotalaria + vetch /soybean; System 2: vetch +oat + turnip/soybean; System 3: sunflower/soybean; System 4: millet/soybean; System 5: corn/soybean; System 6: wheat/soybean; and System 7: oat/soybean. Plant height, insertion height of first pod, number of plant ramifications, number of pods per plant, soybean yield, and mass of 100 grains were evaluated. It was concluded that in a no-tillage consolidated system, various species can be used in rotation or succession with soybean, without affecting the components of the leguminous yield.

  15. On the effect of crop rotation on artificially established weed species in two field experiments

    Directory of Open Access Journals (Sweden)

    Flucke, Christoph

    2014-02-01

    Full Text Available Several studies indicate links between regional occurrence of well adapted weed species and crop rotations. Monocultures or very short crop rotation, which increased in the past decades are crucial for the establishment and dispersion of problematic weed species. In this study the impact of crop rotation on the occurrence of the species Amaranthus retroflexus (L., Anchusa arvensis (L. M. Bieb., Echinochloa crus-galli (L., Galium aparine (L., Geranium pusillum (L., Sisymbrium officinale (L., Solanum nigrum (L., Stellaria media (L. Vill., Viola arvensis Murray is investigated in four crop rotations with varying potential of crop health risks. Therefore, maize (M, oilseed rape (WR and winter wheat [early sowing (WWF and late sowing (WWS] are cropped in four different rotations (M, WR – WWF, WR – M – WWS and WR – WWF – M – WWS at two study sites in Germany since year 2008 (Rostock and 2009 (Göttingen. At the start of the project selected weed species were sown into some plots in order to simulate an artificial similar weed pressure. In all plots weed species densities were counted before spraying in a standardized observation method. Analyses of four, respectively three years give evidences of crop specific effects regarding A. arvensis, E. crus-galli, G. pusillum, S. nigrum and S. media. Moreover, first effects of crop rotations on problematic weed species indicates that expanding crop rotations is a preventive tool to reduce weed densities.

  16. PRE-PLANT CROP ROTATION AND COMPOST AMENDMENTS FOR IMPROVING RASPBERRY ESTABLISHMENT

    Science.gov (United States)

    Two preplant treatments, a sorghum x sudangrass hybrid (Sudex) - rapeseed crop rotation, and a preplant compost amendment treatment, were compared to a control corn-barley rotation for alleviating replant problems on a field with a long history of perennial fruit crops. A raspberry selection trial ...

  17. Genome Scan of Diabrotica virgifera virgifera for Genetic Variation Associated with Crop Rotation Tolerance

    Science.gov (United States)

    Crop rotation has been a valuable technique for control of the western corn rootworm, Diabrotica virgifera virgifera, for almost a century. However, during the last two decades, crop rotation has ceased to be effective in an expanding area of the United States Corn Belt. This failure appears to be d...

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

    Scientific Electronic Library Online (English)

    Meire Aparecida Silvestrini, Cordeiro; José Eduardo, Corá; Ely, Nahas.

    2012-12-01

    Full Text Available Sistemas autossustentáveis favorecem as populações microbianas devido à conservação e ao aumento da matéria orgânica no solo. Além disso, as plantas que fazem parte desses sistemas promovem o efeito rizosférico, por meio da zona de influência das raízes, que resulta no aumento da atividade e na modi [...] ficação da população microbiana. O objetivo deste trabalho foi avaliar o efeito da rotação de culturas de inverno sobre sequências de verão, em sistema de semeadura direta, nos atributos bioquímicos (amilase, urease, celulase e protease) e químicos (carbono orgânico total - COT, carboidratos totais e proteínas totais) em solo rizosférico (SR) e não rizosférico (SNR). Este estudo foi constituído de três culturas de inverno: milho (Zea mays L.), girassol (Helianthus anuus L.) e guandu (Cajanus cajan (L.) Millsp), que estavam em rotação sobre três sequências de verão: soja/soja (Glycine max L.), milho/milho e soja/milho, e duas posições no solo: solo aderido às raízes das plantas (SR) e solo da entrelinha de plantio (SNR). As atividades da amilase, celulase, protease e urease no SR foram 16, 85, 62 e 100 % maiores do que no SNR; para COT e proteínas totais a diferença foi de 21 %. Das culturas de inverno, o milho foi a que mais estimulou as atividades das enzimas amilase, celulase, urease e protease no SR, bem como a atividade das enzimas amilase, urease e protease no SNR. De modo geral, os teores de proteínas totais não foram influenciados pelas culturas de inverno e pelas sequências de verão; os carboidratos totais foram influenciados pelas culturas de inverno milho e girassol. Para o COT houve influência apenas da sequência de verão milho/milho. Os atributos bioquímicos e químicos avaliados neste estudo podem ser utilizados como indicadores das alterações no solo promovidas pelas culturas de inverno e pelas sequências de verão. Abstract in english Self-sustaining systems encourage microbial populations due to the conservation and improvement of organic matter in the soil. In addition, the plants constituents of these systems produce the rhizospheric effect through the influence zone of the roots, increasing activity and modifying the microbia [...] l population. The objective of this study was to evaluate the effect of winter crop rotation and summer crop sequences in a no tillage system, based on biochemical (amylase, urease, cellulase, and protease) and chemical (organic carbon, total carbohydrates, and total protein) characteristics in rhizospheric (SR) and non-rhizospheric soil (SNR). Three winter crops were studied: corn (Zea mays L.), sunflower (Helianthus anuus L.), and pigeon pea (Cajanus cajan (L.) Millsp), in rotation with three summer sequences: soybean/soybean (Glycine max L.), corn/corn, and soybean/corn. Samples were taken from soil adhering to the plant roots (SR) and from in-between the rows (SNR). The activities of amylase, cellulase, protease, and urease in SR were 16, 85, 62, and 100 % higher, respectively, than in SNR. For total organic carbon and total protein, the difference was 21 %. Of the winter crops, corn stimulated higher amylase, cellulase, protease, and urease activity in SR, as well as amylase, protease, and urease activity in SNR. The winter crops and the summer sequences did not affect total protein levels. The total carbohydrates were influenced by winter corn and sunflower crops. Only the summer corn/corn sequence influenced total organic carbon. The biochemical and chemical properties analyzed in this study can be used as indicators of changes in soil caused by winter crops and summer sequences.

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

    Science.gov (United States)

    Esser, Aaron D; Milosavljevi?, 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. PMID:26470320

  20. 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

    2011-01-01

    The effects of nitrogen (N) availability related to fertilizer type, catch crop management, and rotation composition on cereal yield and grain N were investigated in four organic and one conventional cropping systems in Denmark using the FASSET model. The four-year rotation studied was: spring 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) and undersowing catch crops (OF + C + M), a system with manure but without undersowing catch crops (OF ? C + M), and a system without manure and with catch crops (OF + C ? M). A grass-clover green manure was used as N fixing crop in the other organic system with catch crops (OG + C + M). Cuttings of grass-clover were removed from the plots and an equivalent amount of total-N in pig slurry was applied to the cropping system. Theconventional rotation included mineral fertilizer and catch crops (CF + C + F), although only non-legume catch crops were used. Measurements of cereal dry matter (DM) at harvest and of grain N contents were done in all plots. On average the FASSET model was able to predict the yield and grain N of cereals with a reasonable accuracy for the range of cropping systems and soil types studied, having a particularly good performance on winter wheat. Cereal yields were better on the more loamy soil. DM yield and grain N content were mainly influenced by the type and amount of fertilizer-N at all three locations. Although a catch crop benefit in terms of yield and grain N was observed in most of the cases, a limited N availability affected the cereal production in the four organic 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

  1. Faba bean in cropping systems

    DEFF Research Database (Denmark)

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

    2010-01-01

    The grain legume (pulse) faba bean (Vicia faba L.) is grown world-wide as a protein source for food and feed. At the same time faba bean offers ecosystem services such as renewable inputs of nitrogen (N) into crops and soil via biological N2 fixation, and a diversification of cropping systems. Even though the global average grain yield has almost doubled during the past 50 years the total area sown to faba beans has declined by 56% over the same period. The season-to-season fluctuations in grain...

  2. 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.

  3. Soil microbial biomass and mineralizable carbon as a function of crop rotation and soil acidity amendment in a no-tillage system in Brazil

    Science.gov (United States)

    Tropical climate and weathered soil conditions create significant challenges for increasing soil organic matter content. However, crop management strategies could affect short-term dynamics of active fractions of soil organic matter. Thus, our aim was to evaluate the microbial biomass and mineraliza...

  4. 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 prospective policies. PMID:22944220

  5. 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

    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 long term integrated effects tillage and rotation. We studied the issue using a 30...... L.) and R8, (C-C-S-S) corn, corn, soybean (Glycine max L.), soybean. A red clover (Trifolium pretense L.) cover crop was under seeded in oats and spring barley in R6. In 2010, first year corn was grown in R6 and R8. The tillage treatments included no tillage, NT and mouldboard plowing, MP. Topsoil...... 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...

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

    DEFF Research Database (Denmark)

    Askegaard, M; Olesen, JØrgen E

    2011-01-01

    Two main challenges facing organic arable farming are the supply of nitrogen (N) to the crop and the control of perennial weeds. Nitrate leaching from different organic arable crop rotations was investigated over three consecutive four-year crop rotations in a field experiment at three locations in Denmark (12 years in total). The experimental treatments were: (i) crop rotation, (ii) catch crop and (iii) animal manure. Nitrate leaching was estimated from measured soil nitrate concentration in ceramic suction cells and modelled drainage. There were significant effects on annual N leaching of location (coarse sand > loamy sand > sandy loam) and catch crops (without > with). Including a grass-clover green manure on 25% of the area did not increase N leaching compared with crop rotations without green manure. Also the application of animal manure did not influence N leaching, probably because even in the manured treatments the application rate was lower than crop demand. The results identify management of crop and soil during autumn as the main determinant of N leaching. Nitrate leaching was lowest for a catch crop soil cover during autumn and winter (avg. 20 kg N ha?1), a soil cover of weeds/volunteers had on avg. 30 kg N ha?1, and the largest N leaching losses were found after stubble cultivation (avg. 55 kg N ha?1). The N leaching losses increased with increasing number of autumn soil cultivations

  7. Carbon stock and its compartments in a subtropical oxisol under long-term tillage and crop rotation systems / Estoque e compartimentos de carbono em um latossolo vermelho subtropical sob diferentes sistemas de longo prazo de preparo e rotação de culturas

    Scientific Electronic Library Online (English)

    Ben-Hur Costa de, Campos; Telmo Jorge Carneiro, Amado; Cimélio, Bayer; Rodrigo da Silveira, Nicoloso; Jackson Ernani, Fiorin.

    2011-06-01

    Full Text Available A matéria orgânica do solo (MOS) desempenha papel relevante na qualidade do solo e pode atuar como dreno de C-CO2 atmosférico em solos sob sistemas de manejo conservacionista. Este estudo foi realizado com o objetivo de investigar o efeito de longo prazo (19 anos) de sistemas de preparo do solo (PC- [...] preparo convencional e PD-plantio direto) e de rotação de culturas (R0- sucessão de monoculturas, R1- rotação de culturas de inverno e R2- rotação intensiva de culturas) no estoque de carbono (C) orgânico total, particulado e associado a minerais de um Latossolo Vermelho, originalmente degradado, do Sul do Brasil. O clima é subtropical úmido Cfa 2, segundo a classificação de Köppen, com média anual de precipitação pluvial de 1.774 mm e média anual de temperatura de 19,2 ºC. As parcelas experimentais foram divididas em três segmentos, e em cada um destes foram coletadas amostras nas profundidades de 0-0,05, 0,05-0,10, 0,10-0,20 e 0,20-0,30 m. As amostras foram coletadas por meio da abertura manual de pequenas trincheiras. O estoque de C no solo apresentou relação linear com o aporte anual de C, independentemente do sistema de preparo investigado. Assim, o preparo do solo teve pequeno efeito no incremento da taxa de decomposição da MOS. Na camada de 0-0,30 m, a taxa de sequestro de C variou de zero a 0,51 Mg ha-1 ano-1 considerando o tratamento CT R0 como referência, sendo a rotação de culturas uma estratégia mais eficiente em determinar o acúmulo de C do que os sistemas de preparo. Na média dos sistemas de cultura, uma taxa de sequestro de C de 0,13 Mg ha-1ano-1 foi observada sob PD em relação ao PC. Isso é claro? Esse resultado foi determinado pelo maior aporte de C proporcionado pela melhoria da qualidade do solo em PD adotado por longo prazo. A fração particulada de C foi um indicador eficiente da qualidade dos sistemas de manejo, enquanto o C orgânico associado aos minerais foi um importante dreno de C-CO2 atmosférico nesse Latossolo argiloso. A retenção de C nessa fração estável da MOS contribuiu com 81 e 89 % do total de C sequestrado no solo em PD, nos sistemas R1 e R2, respectivamente. O maior índice de manejo de C foi verificado sob PD R2, confirmando o potencial de práticas de manejo em melhorar qualitativamente o C armazenado no solo, em relação ao PC R0. Esses resultados mostram que a diversificação da rotação de culturas, notadamente com a inclusão de plantas de cobertura, é uma importante estratégia para o sequestro de C-CO2 atmosférico e melhoria da qualidade da MOS em Latossolos subtropicais intemperizados. Abstract in english 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 sy [...] stem, 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 i

  8. 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 positive effect of rotations on soil biological fertility.

  9. EFFECTIVENESS OF TURKEY MANURE IN CROP ROTATION IN THE CONDITIONS OF THE ORDINARY BLACK SOIL ????????????? ?????????? ?????? ? ????? ???????? ??????????? ?? ????????? ????????????

    Directory of Open Access Journals (Sweden)

    Agafonov E. V.

    2012-12-01

    Full Text Available Five-year data of the influence of direct affect and the post action of decomposed turkey droppings on the sunflower husk on crop productivity in three-level field crop rotation of spring barley - sunflower -spring barley and in a comparison of its action with the effect of fertilizers on crop yields were presented in the article. The affect of the droppings exceeded affect of mineral fertilizers on the productivity of field crop ro-tation link in a dose of N90P90K90 on 0,79 t/ ga or on 16%

  10. Efeito de sistemas de manejo de solo e de rotação de culturas na fertilidade do solo, após vinte anos Soil tillage and crop rotation systems on soil fertility attributes after twenty years

    Directory of Open Access Journals (Sweden)

    Henrique Pereira dos Santos

    2008-01-01

    Full Text Available No Brasil, ainda são escassos os estudos disponíveis com experimentos de longa duração em sistemas de manejo de solo e de rotação de culturas. Após vinte anos (1985 a 2005, a fertilidade de solo foi avaliada, em Latossolo Vermelho distrófico típico, em Passo Fundo (RS, em quatro sistemas de manejo de solo (SMSs - 1 plantio direto (PD, 2 cultivo mínimo (CM, 3 preparo convencional de solo com arado de discos e com grade de discos (PCD e 4 preparo convencional de solo com arado de aivecas e com grade de discos (PCA - e em três sistemas de rotação de culturas (SRCs: I (trigo/soja, II (trigo/soja e ervilhaca/milho e III (trigo/soja, ervilhaca/milho e aveia branca/soja, incluindo como testemunha um fragmento adjacente de floresta subtropical (FST. O delineamento experimental foi em blocos completos ao acaso, com parcelas subdivididas e três repetições. As parcelas (4 x 90 m no total de 12, foram constituídas pelos SMSs, e as subparcelas, pelos SRCs (4 x 10 m, no total de 72. Os valores de pH, carbono, P extraível e K disponível diferiram entre os SMSs. No PD, houve acúmulo de carbono orgânico, P e K, na camada superficial. Não houve diferença do nível de matéria orgânica (MOS entre PD e FST, em todas as camadas estudadas. O nível de MOS e os teores de P e K foram mais elevados na camada 0-0,05 m, quando comparados com os observados de 0,15-0,20 m de profundidade, sob PD e nas rotações II e III. Observou-se que em FST os valores de pH, Ca, P e de K foram menores do que os dos SMSs e SRCs.Long term field studies on crop rotation and soil tillage systems under Brazilian conditions are scarce. Soil fertility characteristics were assessed after twenty years (1985 to 2005 on a typical dystrophic Red Latosol located in Passo Fundo, in Rio Grande do Sul, the southernmost state of Brazil. Four soil tillage systems (STS - 1 no-tillage, 2 minimum tillage, 3 conventional tillage using disk plow followed by disk harrow, and 4 conventional tillage using moldboard plow followed by disk harrow - and three crop rotation systems (CRS: I (wheat/soybean, II (wheat/soybean and common vetch/corn, and III (wheat/soybean, common vetch/corn, and white oat/soybean were evaluated, including as check a fragment of subtropical forest (FST. A randomized complete block design, with split-plots and three replicates, was used. The main field plots (4 x 90 m in a total of 12, were the soil tillage systems, whereas the subplots (4 x 10 m, in a total of 72 comprised the crop rotation systems. Values of soil pH, soil organic carbon, extractable P, and exchangeable K were affected by soil tillage systems (STSs. Higher levels of soil organic matter and contents of soil carbon, extractable P, and exchangeable K were observed in the 0-0,05 m layer for the no-tillage system. No statistical differences were found in soil organic matter levels between no-tillage and tropical forest, in any soil layer. Values of soil organic matter, P, and K were higher in the 0-0,05 m layer, when compared to the ones observed in the 0,15-0,20 m layer, in no-tillage and II and III CRSs. Values of pH, Ca, P, and K observed in all STSs and CRSs were higher than in the tropical forest area.

  11. Efeito de sistemas de manejo de solo e de rotação de culturas na fertilidade do solo, após vinte anos / Soil tillage and crop rotation systems on soil fertility attributes after twenty years

    Scientific Electronic Library Online (English)

    Henrique Pereira dos, Santos; Silvio Tulio, Spera; Gilberto Omar, Tomm; Rainoldo Alberto, Kochann; Alexandre, Ávila.

    Full Text Available No Brasil, ainda são escassos os estudos disponíveis com experimentos de longa duração em sistemas de manejo de solo e de rotação de culturas. Após vinte anos (1985 a 2005), a fertilidade de solo foi avaliada, em Latossolo Vermelho distrófico típico, em Passo Fundo (RS), em quatro sistemas de manejo [...] de solo (SMSs) - 1) plantio direto (PD), 2) cultivo mínimo (CM), 3) preparo convencional de solo com arado de discos e com grade de discos (PCD) e 4) preparo convencional de solo com arado de aivecas e com grade de discos (PCA) - e em três sistemas de rotação de culturas (SRCs): I (trigo/soja), II (trigo/soja e ervilhaca/milho) e III (trigo/soja, ervilhaca/milho e aveia branca/soja), incluindo como testemunha um fragmento adjacente de floresta subtropical (FST). O delineamento experimental foi em blocos completos ao acaso, com parcelas subdivididas e três repetições. As parcelas (4 x 90 m) no total de 12, foram constituídas pelos SMSs, e as subparcelas, pelos SRCs (4 x 10 m), no total de 72. Os valores de pH, carbono, P extraível e K disponível diferiram entre os SMSs. No PD, houve acúmulo de carbono orgânico, P e K, na camada superficial. Não houve diferença do nível de matéria orgânica (MOS) entre PD e FST, em todas as camadas estudadas. O nível de MOS e os teores de P e K foram mais elevados na camada 0-0,05 m, quando comparados com os observados de 0,15-0,20 m de profundidade, sob PD e nas rotações II e III. Observou-se que em FST os valores de pH, Ca, P e de K foram menores do que os dos SMSs e SRCs. Abstract in english Long term field studies on crop rotation and soil tillage systems under Brazilian conditions are scarce. Soil fertility characteristics were assessed after twenty years (1985 to 2005) on a typical dystrophic Red Latosol located in Passo Fundo, in Rio Grande do Sul, the southernmost state of Brazil. [...] Four soil tillage systems (STS) - 1) no-tillage, 2) minimum tillage, 3) conventional tillage using disk plow followed by disk harrow, and 4) conventional tillage using moldboard plow followed by disk harrow - and three crop rotation systems (CRS): I (wheat/soybean), II (wheat/soybean and common vetch/corn), and III (wheat/soybean, common vetch/corn, and white oat/soybean) were evaluated, including as check a fragment of subtropical forest (FST). A randomized complete block design, with split-plots and three replicates, was used. The main field plots (4 x 90 m) in a total of 12, were the soil tillage systems, whereas the subplots (4 x 10 m), in a total of 72 comprised the crop rotation systems. Values of soil pH, soil organic carbon, extractable P, and exchangeable K were affected by soil tillage systems (STSs). Higher levels of soil organic matter and contents of soil carbon, extractable P, and exchangeable K were observed in the 0-0,05 m layer for the no-tillage system. No statistical differences were found in soil organic matter levels between no-tillage and tropical forest, in any soil layer. Values of soil organic matter, P, and K were higher in the 0-0,05 m layer, when compared to the ones observed in the 0,15-0,20 m layer, in no-tillage and II and III CRSs. Values of pH, Ca, P, and K observed in all STSs and CRSs were higher than in the tropical forest area.

  12. Current utilization and perspective of short rotation energy crops

    International Nuclear Information System (INIS)

    World-wide, there is an increasing demand for phytomass for production of renewable CO2-neutral fuel and as an inexpensive environmentally friendly raw material source for food and industry production. Together with the development of appropriate technology, is becoming a matter of paramount importance. Amaranth species hold much promise in fulfilling these demands. Amaranth could be characterised as a high energy multipurpose C4 plant, fits the bill as a true '4F crop' (Food, Feed, Fuel and Fibre) as well as being a short cycle, drought and salinity tolerant crop. The Amaranth agro-ecological system is a key link in the sustainable production of agriculture. It will play an important role in 'healthy' food as well as environmental protection in the next century. From the environmental point of view it should be mentioned that Amaranth is the plant species, which is also suitable for marginal lands and contaminated soils. It is known for its dry or saline land resistance as well as contamination by radioactive dust or other harmful material. (author)

  13. 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 sobre o acúmulo de sais no solo e a produtividade de milho e feijão-de-corda em sistema de rotação. O experimento foi conduzido em campo, utilizando-se do delineamento em blocos ao acaso, com cinco repetições. O primeiro cultivo foi instalado durante a estação seca de 2007, com a cultura do milho irrigada com água de diferentes salinidades (0,8; 2,2; 3,6 e 5,0 dS m-1. As plantas foram coletadas aos 90 dias após a semeadura (DAS, sendo realizadas as avaliações: crescimento vegetativo, produção de grãos por planta, matéria seca de 1.000 grãos e produtividade. Durante a estação chuvosa de 2008, foi cultivado o feijão caupi nas mesmas parcelas que foram cultivadas com milho. Ao final do ciclo, as plantas foram coletadas, sendo realizadas avaliações de crescimento vegetativo e produtividade. Amostras de solo foram coletadas antes e após o cultivo do milho e ao final do cultivo com feijão caupi. A salinidade da água de irrigação acima 2,2 dS m-1 reduziu a produtividade do milho durante o período seco. Os elevados totais de precipitação pluviométrica durante a estação chuvosa proporcionaram a lixiviação dos sais acumulados durante o cultivo na estação seca e eliminaram os possíveis efeitos negativos da salinidade sobre o feijão caupi. Porém, o feijão caupi apresentou um comportamento atípico com uma expressiva proporção de massa vegetativa e baixa produção de vagens, o que reduziu a eficiência dessa estratégia de rotação de culturas, nas condições do presente estudo.

  14. 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

    Scientific Electronic Library Online (English)

    Claudivan F., Lacerda; Geocleber G., Sousa; Francisco L. B., Silva; Francisco V. A., Guimarães; Giovana L., Silva; Lourival F., Cavalcante.

    Full Text Available 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 d [...] e baixa salinidade na estação chuvosa sobre o acúmulo de sais no solo e a produtividade de milho e feijão-de-corda em sistema de rotação. O experimento foi conduzido em campo, utilizando-se do delineamento em blocos ao acaso, com cinco repetições. O primeiro cultivo foi instalado durante a estação seca de 2007, com a cultura do milho irrigada com água de diferentes salinidades (0,8; 2,2; 3,6 e 5,0 dS m-1). As plantas foram coletadas aos 90 dias após a semeadura (DAS), sendo realizadas as avaliações: crescimento vegetativo, produção de grãos por planta, matéria seca de 1.000 grãos e produtividade. Durante a estação chuvosa de 2008, foi cultivado o feijão caupi nas mesmas parcelas que foram cultivadas com milho. Ao final do ciclo, as plantas foram coletadas, sendo realizadas avaliações de crescimento vegetativo e produtividade. Amostras de solo foram coletadas antes e após o cultivo do milho e ao final do cultivo com feijão caupi. A salinidade da água de irrigação acima 2,2 dS m-1 reduziu a produtividade do milho durante o período seco. Os elevados totais de precipitação pluviométrica durante a estação chuvosa proporcionaram a lixiviação dos sais acumulados durante o cultivo na estação seca e eliminaram os possíveis efeitos negativos da salinidade sobre o feijão caupi. Porém, o feijão caupi apresentou um comportamento atípico com uma expressiva proporção de massa vegetativa e baixa produção de vagens, o que reduziu a eficiência dessa estratégia de rotação de culturas, nas condições do presente estudo. Abstract in english 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.

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

    DEFF Research Database (Denmark)

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

    2014-01-01

    The effects of projected changes in climate and atmospheric CO2 concentration on productivity and nitrogen (N) leaching of characteristic arable and pig farming rotations in Denmark were investigated with the FASSET simulation model. The LARS weather generator was used to provide climatic data for the baseline period (1961–90) and in combination with two regional circulation models (RCM) to generate climatic data under the Intergovernmental Panel on Climate Change (IPCC) A1B emission scenario fo...

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

    Science.gov (United States)

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

    2015-05-26

    Rotational harvesting is one of the oldest management strategies applied to terrestrial and marine natural resources, with crop rotations dating back to the time of the Roman Empire. The efficacy of this strategy for sessile marine species is of considerable interest given that these resources are vital to underpin food security and maintain the social and economic wellbeing of small-scale and commercial fishers globally. We modeled the rotational zone strategy applied to the multispecies sea cucumber fishery in Australia's Great Barrier Reef Marine Park and show a substantial reduction in the risk of localized depletion, higher long-term yields, and improved economic performance. We evaluated the performance of rotation cycles of different length and show an improvement in biological and economic performance with increasing time between harvests up to 6 y. As sea cucumber fisheries throughout the world succumb to overexploitation driven by rising demand, there has been an increasing demand for robust assessments of fishery sustainability and a need to address local depletion concerns. Our results provide motivation for increased use of relatively low-information, low-cost, comanagement rotational harvest approaches in coastal and reef systems globally. PMID:25964357

  17. Overcoming weed management challenges in cover crop-based organic rotational no-till soybean production in the Eastern US

    Science.gov (United States)

    Cover crop-based, organic rotational no-till soybean production has been gaining traction in the Eastern region of the United States because of the ability of this new system to enhance soil conservation, reduce labor requirements, and decrease diesel fuel use compared to traditional organic product...

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

    OpenAIRE

    Victor B. Ella; Reyes, Manuel R.; Mercado, Jr., Agustin; Adrian, Ares; Padre, Rafael

    2016-01-01

    Conservation agriculture involves minimum soil disturbance, continuous ground cover, and diversified crop rotations or mixtures. Conservation agriculture production systems (CAPS) have the potential to improve soil quality if appropriate cropping systems are developed.  In this study, five CAPS including different cropping patterns and cover crops under two fertility levels, and a plow-based system as control, were studied in a typical upland agricultural area in northern Mindanao in the Phil...

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

    OpenAIRE

    Victor B. Ella; Reyes, Manuel R.; Agustin Mercado, Jr.; Ares Adrian; Rafael Padre

    2016-01-01

    Conservation agriculture involves minimum soil disturbance, continuous ground cover, and diversified crop rotations or mixtures. Conservation agriculture production systems (CAPS) have the potential to improve soil quality if appropriate cropping systems are developed. In this study, five CAPS including different cropping patterns and cover crops under two fertility levels, and a plow-based system as control, were studied in a typical upland agricultural area in northern Mindanao in the Phil...

  20. 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; Ambus, Per; Olesen, J.E.; Porter, P.R.; Petersen, S.O.

    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. The...... main objective of this study was to compare nitrous oxide (N2O) emissions from soil under winter wheat (Triticum aestivum L.) within three organic and one conventional cropping system that differed in type of fertilizer, presence of catch crops and proportion of N2-fixing crops. The study was...... replicated in two identical long-term crop rotation experiments on sandy loam soils under different climatic conditions in Denmark (Flakkebjerg—eastern Denmark and Foulum—western Denmark). The conventional rotation received 165–170 kg N ha−1 in the form of NH4NO3, while the organic rotations received 100...

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

    International Nuclear Information System (INIS)

    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)

  2. Influence of Rotation Crops on the Strawberry Pathogens Pratylenchus penetrans, Meloidogyne hapla, and Rhizoctonia fragariae

    OpenAIRE

    LaMondia, J.A.

    1999-01-01

    Field microplot, small plot, and greenhouse experiments were conducted to determine the effects of rotation crops on Pratylenchus penetrans, Meloidogyne hapla, and Rhizoctonia fragariae populations. Extraction of P. penetrans from roots and soil in microplots and field plots planted to rotation crops was highest for Garry oat, lowest for Triple S sorgho-sudangrass and Saia oat, and intermediate for strawberry, buckwheat, and canola. Isolation of R. fragariae from bait roots was highest for st...

  3. Nitrogen dynamics in soybean-based crop rotations under conventional and zero tillage in Brazil

    International Nuclear Information System (INIS)

    Approximately 70% of Brazilian agriculture is based on the cultivation of highly weathered soils located in tropical and subtropical savannah areas, where the zero or no tillage (ZT) system is now considered as the best alternative to the traditional conventional tillage (CT). During the period 1999-2004 the Agrobiology Centre of Embrapa implemented a research program using nuclear and related techniques to study the main processes involved in the dynamics and cycling of N for predominant crop rotations grown at five locations under ZT in comparison to CT, on acidic savannah soils of both southern and Cerrado regions of Brazil. The most relevant results of these studies were: (1) The soybean crop derived a high proportion of its N (over 80%) from biological nitrogen fixation (BNF). The BNF system is so efficient that attempts to increase grain yields by addition of N fertilizer are hardly ever successful as long as the plants have been effectively inoculated with the recommended Bradyrhizobium strains. (2) The N fertilizer use efficiency by the maize crop fertilized with 80 to 90 kg N ha-1 varied from 40 to 60%. (3). A maximum 10% of N-urea applied broadcast over the soil surface (40 kg N ha-1) in a maize crop was lost via NH3 volatilization, with the highest values under ZT. (4). The inclusion of green manure legumes (GMLs) such as lupin and vetch, which are highly efficient in BNF was essential to promote a positive soil N balance in crop rotations and to increase the stock of soil organic C. (5) Less than 900 g N-N2O ha-1 yr-1 were lost from the soil surface, and the highest values were found under CT. (6) Even thought the contribution of BNF to the Brazilian soybean crop is high (over 80%), the accurate assessment of this input to the soil N balance still remain unclear due to methodological problems using the leaf labeling technique to estimate residual below-ground N. Results obtained so far suggest that these methodological issues need to be overcome before these estimates can be considered as reliable. These results demonstrate the enormous potential impact of BNF in legumes such as soybean and green manures and their management under ZT and CT on the N cycling processes and overall C and N stocks in tropical acid savannah soils, thus contributing to the productivity and sustainability of the agricultural production systems. (author)

  4. SOIL HYDRAULIC AND ELECTRICAL PROPERTIES FOR DIFFERENT SOILS, SLOPES, AND CROP ROTATIONS

    Science.gov (United States)

    Crop management can alter soil physical properties, but variability of these properties may mask treatment effects. The purpose of this study was to compare soil physical property variation under two crop rotations, and to examine interrelations among different soil physical properties. A six-year r...

  5. Análise de risco em quatro sistemas de rotação de culturas para trigo, num período de dez anos, em Passo Fundo, RS / Risk analysis of four crop rotation systems for wheat, over a ten-year period, in Passo Fundo, RS

    Scientific Electronic Library Online (English)

    Henrique Pereira dos, Santos; Ivo, Ambrosi; Julio Cesar Barreneche, Lhamby.

    1999-04-01

    Full Text Available Num período de dez anos (1980 a 1989), foi conduzido, na Embrapa-Centro Nacional de Pesquisa de Trigo (CNPT), em Passo Fundo, RS, experimento reunindo quatro sistemas de rotação de culturas para trigo (Triticum aestivum L.): sistema I (trigo/soja); sistema II (trigo/soja, colza/soja, cevada/soja e t [...] remoço ou serradela/milho); sistema III (trigo/soja, trevo vesiculoso/trevo vesiculoso, trevo vesiculoso/milho, de 1980 a 1983, e trigo/soja, aveia branca/soja e ervilhaca/milho, de 1984 a 1989); e sistema IV (trigo/soja, colza/soja, linho/soja e tremoço ou serradela/milho). Utilizou-se o delineamento de blocos ao acaso, com quatro repetições e parcelas com área útil de 120 m². No presente trabalho, mostra-se a análise de risco naquele período. Foram aplicados dois tipos de análise na receita líquida dos sistemas: análise da média variância e análise de risco (distribuição de probabilidade acumulada e dominância estocástica). Pela análise da média variância da receita líquida, os sistemas II e IV foram superiores aos sistemas I e III. Pelo método da dominância estocástica, o sistema II apresentou- se como a melhor alternativa de produção a ser oferecida aos agricultores, do ponto de vista de lucratividade e menor risco. Abstract in english During ten years (1980 to 1989), at the Embrapa-Centro Nacional de Pesquisa de Trigo (CNPT), in Passo Fundo, RS, Brazil, the effects of crop rotation systems on wheat (Triticum aestivum L.) were assessed. Four rotation systems for wheat were studied: system I (wheat/soybean); system II (wheat/soybea [...] n, rapeseed/soybean, barley/soybean, lupine or serradella/corn); system III (wheat/soybean, arrowleaf clover/arrowleaf clover, and arrowleaf clover/corn, from 1980 to 1983, and wheat/soybean, white oats/soybean, and common vetch/corn, from 1984 to 1989); and system IV (wheat/soybean, rapeseed/soybean, flax/soybean, and lupine or serradella/corn). A randomized complete block design, with four replications and plots with 120 m², was used. Risk analysis over that period is presented in this paper. Two types of analysis were applied to the net return of the systems: mean-variance analysis and risk analysis (safety-first and stochastic dominance). By the mean-variance analysis, systems II and IV showed higher net returns as compared to systems I and III. The system II showed the highest profit and the lowest risk to be offered to the farmer, as compared to the remaining systems studied.

  6. Análise de risco em quatro sistemas de rotação de culturas para trigo, num período de dez anos, em Passo Fundo, RS Risk analysis of four crop rotation systems for wheat, over a ten-year period, in Passo Fundo, RS

    Directory of Open Access Journals (Sweden)

    Henrique Pereira dos Santos

    1999-04-01

    Full Text Available Num período de dez anos (1980 a 1989, foi conduzido, na Embrapa-Centro Nacional de Pesquisa de Trigo (CNPT, em Passo Fundo, RS, experimento reunindo quatro sistemas de rotação de culturas para trigo (Triticum aestivum L.: sistema I (trigo/soja; sistema II (trigo/soja, colza/soja, cevada/soja e tremoço ou serradela/milho; sistema III (trigo/soja, trevo vesiculoso/trevo vesiculoso, trevo vesiculoso/milho, de 1980 a 1983, e trigo/soja, aveia branca/soja e ervilhaca/milho, de 1984 a 1989; e sistema IV (trigo/soja, colza/soja, linho/soja e tremoço ou serradela/milho. Utilizou-se o delineamento de blocos ao acaso, com quatro repetições e parcelas com área útil de 120 m². No presente trabalho, mostra-se a análise de risco naquele período. Foram aplicados dois tipos de análise na receita líquida dos sistemas: análise da média variância e análise de risco (distribuição de probabilidade acumulada e dominância estocástica. Pela análise da média variância da receita líquida, os sistemas II e IV foram superiores aos sistemas I e III. Pelo método da dominância estocástica, o sistema II apresentou- se como a melhor alternativa de produção a ser oferecida aos agricultores, do ponto de vista de lucratividade e menor risco.During ten years (1980 to 1989, at the Embrapa-Centro Nacional de Pesquisa de Trigo (CNPT, in Passo Fundo, RS, Brazil, the effects of crop rotation systems on wheat (Triticum aestivum L. were assessed. Four rotation systems for wheat were studied: system I (wheat/soybean; system II (wheat/soybean, rapeseed/soybean, barley/soybean, lupine or serradella/corn; system III (wheat/soybean, arrowleaf clover/arrowleaf clover, and arrowleaf clover/corn, from 1980 to 1983, and wheat/soybean, white oats/soybean, and common vetch/corn, from 1984 to 1989; and system IV (wheat/soybean, rapeseed/soybean, flax/soybean, and lupine or serradella/corn. A randomized complete block design, with four replications and plots with 120 m², was used. Risk analysis over that period is presented in this paper. Two types of analysis were applied to the net return of the systems: mean-variance analysis and risk analysis (safety-first and stochastic dominance. By the mean-variance analysis, systems II and IV showed higher net returns as compared to systems I and III. The system II showed the highest profit and the lowest risk to be offered to the farmer, as compared to the remaining systems studied.

  7. Análise econômica de sistemas de rotação de culturas para trigo, num período de dez anos, sob plantio direto Economic analysis of crop rotation systems for wheat, over a ten year period, under no-tillage

    Directory of Open Access Journals (Sweden)

    Henrique Pereira dos Santos

    1999-12-01

    Full Text Available Durante os anos de 1984 a 1993, foi conduzido, em Guarapuava, PR, experimento composto de sistemas de rotação de culturas para trigo: sistema I (trigo/soja; sistema II (trigo/soja e ervilhaca/milho, de 1984 a 1989, e trigo/soja e aveia-branca/soja, de 1990 a 1993; sistema III (trigo/soja, linho/soja e ervilhaca/milho, de 1984 a 1989, e trigo/soja, ervilhaca/milho e aveia-branca/soja, de 1990 a 1993; e sistema IV (trigo/soja, leguminosas/milho, cevada/soja e aveia-branca/soja. A análise econômica do período é apresentada neste trabalho. De 1984 a 1989, os sistemas I, II, III e IV não mostraram diferenças entre as médias quanto à receita líquida. Da mesma forma, de 1990 a 1993, os sistemas II, III e IV não diferiram significativamente no tocante a receita líquida, em relação ao sistema I; no entanto, considerando-se as comparações anuais, o sistema II apresentou maior lucratividade do que o sistema I, em seis anos, e não diferiu em quatro anos, sendo, portanto, aquele, uma boa alternativa em relação a este, principalmente no primeiro período.From 1984 to 1993, in Guarapuava, Paraná, Brazil, the effect of crop rotation systems on wheat were assessed. Four rotation systems for wheat were studied: system I (wheat/soybean; system II (wheat/soybean and common vetch/corn, from 1984 to 1989, and wheat/soybean and white oats/soybean, from 1990 to 1993; system III (wheat/soybean, flax/soybean, and common vetch/corn, from 1984 to 1989, and wheat/soybean, common vetch/corn, and white oats/soybean, from 1990 to 1993; and system IV (wheat/soybean, legume/corn, barley/soybean, and white oats/soybean. The economic analysis on that period is presented in this paper. From 1984 to 1989, systems I, II, III, and IV showed no differences in their net return means. Similarly, from 1990 to 1993, systems II, III, and IV mean net returns did not differ significantly in relation to the system I; however, considering the annual comparison, the system II showed higher profit than the system I in six years and did not differ in four years, making it a good alternative, mainly in the first period.

  8. Soil properties, crop production and greenhouse gas emissions in organic and conventional cropping systems

    DEFF Research Database (Denmark)

    Chirinda, Ngonidzashe; Olesen, JØrgen E

    2010-01-01

    Organic and conventional farming practices differ in the use of several management strategies, including use of catch crops, green manure, and fertilization, which may influence soil properties, greenhouse gas emissions and productivity of agroecosystems. An 11-yr-old field experiment on a sandy loam soil in Denmark was used to compare several crop rotations with respect to a range of physical, chemical and biological characteristics related to carbon (C) and nitrogen (N) flows. Four organic rotations and an inorganic fertilizer-based system were selected to evaluate effects of fertilizer type, catch crops, of grass-clover used as green manure, and of animal manure application. Soil was sampled from winter wheat and spring barley plots on 19 September 2007, 14 April 2008 and 22 September 2008, i.e. before, during, and after the growth season. The soils were analyzed for multiple attributes: total soil organic carbon (SOC), total N, microbial biomass N (MBN), potentially mineralizable N (PMN), and levels of potential ammonium oxidation (PAO) and denitrifying enzyme activity (DEA). In situ measurements of soil heterotrophic carbon dioxide (CO2) respiration and nitrous oxide emissions were 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 growth was monitored and grain yields measured at harvest maturity. The different management strategies between 1997 and 2007 led to soil carbon inputs that were on average 18–68% and 32–91% higher in the organic than inorganic fertilizer-based rotations for the sampled winter wheat and spring barley crops, respectively. Nevertheless, SOC levels in 2008 were similar across systems. The cumulative soil respiration for the period February to August 2008 ranged between 2 and 3 t CO2–C ha?1 and was correlated (r = 0.95) with average C inputs. In the organic cropping systems, pig slurry application 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 < 0.05). Crop yields in 2008 were generally lower in the low-input organic rotations than in the high-input inorganic fertilizer-based system; only spring barley in rotations with pig slurry application and incorporation of a catch crop prior to sowing obtained grain yields similar to levels achieved in the system where inorganic fertilizer was applied. These results suggest that within organic cropping systems, both microbial activity and crop yields could be enhanced through inclusion of catch crops. However, the timing of catch crop incorporation is critical.

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

    Science.gov (United States)

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

    2015-11-01

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

  10. Nitrous oxide emissions from crop rotations including wheat, oilseed rape and dry peas

    Science.gov (United States)

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

    2013-03-01

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

  11. 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

    OpenAIRE

    Elcio Liborio Balota; Miriam Kanashiro; Arnaldo Colozzi Filho; Diva Souza Andrade; Richard Peter Dick

    2004-01-01

    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 spli...

  12. Changes in Soil Organic Carbon of Crop Rotations in the Northern Corn Belt

    Science.gov (United States)

    Diversified crop rotation may reduce fertilizer nitrogen (N) input for corn (Zea mays L.) and increase soil organic carbon (SOC) storage. Objectives were to determine effect of rotation and N on soil C sequestration. The experiment, started in 1990, was on a Barnes sandy clay loam near Brookings, SD...

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

    Science.gov (United States)

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

    2015-04-01

    Crop residue harvest is a common practice in the Midwestern USA for the ethanol production. However, excessive removal of crop residues from the soil surface contributes to the degradation of important soil quality indicators such as soil organic carbon (SOC). Addition of a cover crop may help to mitigate these negative effects. The present study was set up to assess the impacts of corn (Zea mays L.) residue removal and cover crops on various soil quality indicators and surface greenhouse gas (GHG) fluxes. The study was being conducted on plots located at the North Central Agricultural Research Laboratory (NCARL) in Brookings, South Dakota, USA. Three plots of a corn and soybean (Glycine max (L.) Merr.) rotation under a no-till (NT) system are being monitored for soils and surface gas fluxes. Each plot has three residue removal (high residue removal, HRR; medium residue removal, MRR; and low residue removal, LRR) treatments and two cover crops (cover crops and no cover crops) treatments. Both corn and soybean are represented every year. Gas flux measurements were taken weekly using a closed static chamber method. Data show that residue removal significantly impacted soil quality indicators while more time was needed for an affect from cover crop treatments to be noticed. The LRR treatment resulted in higher SOC concentrations, increased aggregate stability, and increased microbial activity. The LRR treatment also increased soil organic matter (SOM) and particulate organic matter (POM) concentrations. Cover crops used in HRR (high corn residue removal) improved SOC (27 g kg-1) by 6% compared to that without cover crops (25.4 g kg-1). Cover crops significantly impacted POM concentration directly after the residue removal treatments were applied in 2012. CO2 fluxes were observed to increase as temperature increased, while N2O fluxes increased as soil moisture increased. CH4 fluxes were responsive to both increases in temperature and moisture. On average, soils under cover crop management had lower N2O fluxes than soils that did not have a cover crop. Results from this study concluded that it is important to allow crop residues to return to the soil as they help to improve soil quality indicators. The presence of cover crops also will contribute to the improvement of these indicators once established and may help mitigate greenhouse gas emissions.

  14. THE EFFICIENCY OF CULTIVATION OF OILSEED CROPS (CANOLA, SOY IN A FIELD ROTATION FOREST-STEPPE ZONE OF WESTERN SIBERIA

    Directory of Open Access Journals (Sweden)

    Chibis V. V.

    2014-06-01

    Full Text Available In the long-term stationary experiment since 1968, we have studied the influence of crop rotation on soil fertility and productivity. The modernization schemes of field rotations in the direction of alternation crop change were held 40 years later, by introducing a scheme of oilseeds (canola, soy. According to the research, the authors made conclusions about the efficiency of cultivation of oil crops in crop rotations in the region. The resulting materials can be used in the development of crop rotations schemes for forest-steppe of Western Siberia

  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-bean-corn-bean-rice-bean (R4. The severity of F. solani f. sp. phaseoli was evaluated 25 days after planting. The interaction was significant for this variable. The higher severity was under R3 with soil tillage system treatment P1. The lowest severity was under interaction R2 with soil preparation P3. Significant differences were found in the severity of the disease caused by R. solani. Soil tillage system P3 presented significantly higher disease severity than P4, whereas rotation R3 presented significantly higher disease severity when compared to other treatments.

    KEY-WORDS: Rhizoctonia solani, Fusarium solani f. sp. haseoli; cropping practices; fungi.

  16. Effects of contrasting catch crops on nitrogen availability and nitrous oxide emissions in an organic cropping system

    DEFF Research Database (Denmark)

    Li, Xiaoxi; Petersen, Søren O; Sørensen, Peter; Olesen, Jørgen E

    2015-01-01

    Legume-based catch crops (LBCCs) may act as an important source of nitrogen (N) in organic crop rotations because of biological N fixation. However, the potential risk of high nitrous oxide (N2O) emissions needs to be taken into account when including LBCCs in crop rotations. Here, we report the...... harvested N is recycled as fertiliser to the crops in the rotation....

  17. Rendimento de grãos de soja em função de diferentes sistemas de manejo de solo e de rotação de culturas / Soybean yield associated to different soil tillage methods and crop rotations systems

    Scientific Electronic Library Online (English)

    Henrique Pereira dos, Santos; Julio Cesar Barreneche, Lhamby; Silvio Tulio, Spera.

    2006-02-01

    Full Text Available O objetivo do presente trabalho foi avaliar sistemas de manejo de solo e de rotação de culturas sobre o rendimento de grãos e componentes do rendimento de soja durante seis anos. Foram comparados quatro sistemas de manejo de solo - 1) plantio direto, 2) cultivo mínimo, no inverno e semeadura direta, [...] no verão, 3) preparo convencional de solo com arado de discos, no inverno e semeadura direta, no verão e 4) preparo convencional de solo com arado de aivecas, no inverno e semeadura direta, no verão - e três sistemas de rotação de culturas: sistema I (trigo/soja), sistema II (trigo/soja e ervilhaca/milho ou sorgo) e sistema III (trigo/soja, ervilhaca/milho ou sorgo e aveia branca/soja). O delineamento experimental foi de blocos ao acaso, com parcelas subdivididas e três repetições. O rendimento de grãos e o peso de 1.000 grãos de soja cultivada sob plantio direto e sob cultivo mínimo foi superior ao de soja cultivada sob preparo convencional de solo com arado de discos e com arado de aivecas. A maior estatura de plantas de soja ocorreu no plantio direto. O rendimento de grãos de soja cultivada após trigo, no sistema II, foi superior ao de soja cultivada após aveia branca e após trigo, no sistema III, e após trigo, no sistema I. O menor rendimento de grãos, peso de grãos por planta de soja e peso de 1.000 grãos ocorreu quando em monocultura (trigo/soja). Abstract in english The objective of this six-year study was to assess the soil tillage systems and crop rotation systems on soybean grain and yield components were evaluated at Embrapa Trigo in Passo Fundo, RS, Brazil. Four soil tillage systems - 1) no-tillage, 2) minimum tillage in winter and no-tillage in summer, 3) [...] conventional tillage with disk plow in winter and no-tillage in summer, and 4) tillage using a moldboard plow in winter and no-tillage in summer - and three crop rotation systems [system I (wheat/soybean), system II (wheat/soybean and common vetch/corn or sorghum), and system III (wheat/soybean, common vetch/corn or sorghum and white oats/soybean)]. An experimental randomized blocks design, with split-plots and three replications, was used. The yield and weight of 1,000 kernels of soybean grown under no-tillage and minimum tillage was higher than soybean grown conventional soil tillage with disk plow and a moldboard plow. Plant height showed higher in the no-tillage. The yield of soybean grown after wheat, in system II, was higher than soybean grown after white oats and after wheat, in system III, and after wheat, in system I. The lowest soybean yield, grain weight/plant, and weight of 1,000 kernels was obtained in monoculture (wheat/soybean).

  18. How can we improve Mediterranean cropping systems?

    DEFF Research Database (Denmark)

    Benlhabib, O.; Yazar, A.; Qadir, M.; Lourenço, E.; Jacobsen, Sven-Erik

    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 influ...

  19. How can we improve Mediterranean cropping systems?

    DEFF Research Database (Denmark)

    Benlhabib, O.; Yazar, A.; Qadir, M.; Lourenço, E.; Jacobsen, Sven-Erik

    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...

  20. 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; Kristensen, Kristian; Olesen, Jørgen E

    2014-01-01

    . repens recorded in a long-termed crop rotation experiment on coarse sand in Southern Denmark. The study gives an insight into the factors responsible for E. repens population changes and especially those that require particular attention to prevent outbreaks of E. repens. Data originated from three 4......Elytrigia repens is a noxious perennial weed in organic cropping systems in Scandinavia. It can easily spread in any crop type and reach unacceptable infestation levels through its proliferation from rhizome fragments. This study aimed at analyzing and quantifying the population dynamics of E......-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...

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

    Directory of Open Access Journals (Sweden)

    Juliano Carlos Calonego

    2011-06-01

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

  2. 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.

  3. Propriedades físicas do solo em sistemas de rotação de culturas conforme o uso de corretivos da acidez / Soil physical properties in crop rotation systems as affected by liming materials

    Scientific Electronic Library Online (English)

    Gustavo Spadotti Amaral, Castro; Juliano Carlos, Calonego; Carlos Alexandre Costa, Crusciol.

    2011-12-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito de sistemas de rotação de culturas e de corretivos da acidez nas propriedades físicas do solo. O experimento foi realizado entre outubro de 2006 e julho de 2008, em Botucatu, SP, em blocos ao acaso, com parcelas subdivididas e oito repetições. As parcel [...] as foram constituídas por quatro sistemas de rotação: soja/pousio/milho/pousio, soja/aveia-branca/milho/feijão, soja/milheto/milho/guandu e soja/braquiária/milho/braquiária. As subparcelas consistiram do tratamento testemunha, sem correção, e da aplicação de 3,8 Mg ha-1 de calcário dolomítico (PRNT = 90%) ou de 4,1 Mg ha-1 de silicato de cálcio e magnésio (PRNT = 80%), na superfície de um Latossolo Vermelho argiloso. Foram determinadas: estabilidade de agregados, densidade do solo, porosidade total, macro e microporosidade, resistência do solo à penetração e umidade do solo. A aplicação dos corretivos de acidez em superfície não reduz a agregação do solo e aumenta a macroporosidade até 0,20 m de profundidade, após aplicação de silicato, e até 0,10 m, após aplicação de calcário. A manutenção do solo em pousio, na entressafra, prejudica a estruturação do solo, reduz a estabilidade de agregados e aumenta a resistência à penetração nas camadas superficiais. A semeadura de braquiária, entre as safras de verão, aumenta a estabilidade de agregados até 0,10 m de profundidade. Abstract in english The objective of this work was to evaluate the effects of crop rotation systems and liming materials on soil physical properties. The experiment was carried out from October 2006 to July 2008, in Botucatu, SP, Brazil, in a completely randomized block design in a split-plot arrangement with eight rep [...] licates. Main plots consisted of four crop rotation systems: soybean/fallow/maize/fallow, soybean/white-oat/maize/bean, soybean/millet/maize/pigeon pea and soybean/signal grass/maize/signal grass. Subplots consisted of the control treatment, without soil correction, and of the application of 3.8 Mg ha-1 of dolomitic lime (ECC = 90%) or 4.1 Mg ha-1 of calcium-magnesium silicate (ECC = 80%), on the surface of a clayed Rhodic Ferralsol. Aggregate stability, soil bulk density, total porosity, macro and microporosity, soil penetration resistance and moisture content were evaluated. Superficial application of the lime materials does not reduce soil aggregation and increases macroporosity down to 0.20 m, with calcium-magnesium silicate application, and to 0.10 m, when lime is applied. Soil under fallow in off-season decreases aggregate stability and increases soil penetration resistance in upper layers. The cultivation of Congo signal grass, between summer crops, increases aggregate stability down to 0.10-m depth.

  4. NITROGEN TRANSFORMATION FROM POTATO AND ROTATIONAL CROP RESIDUES

    Science.gov (United States)

    This study was conducted to determine the amount of nitrogen (N) from the crop residues and soil organic matter transformed into inorganic forms, i.e. ammonium and nitrate forms, during January through September 2000 in a sandy soil under irrigation. Corn, wheat, and potato residues were evaluated....

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

    Scientific Electronic Library Online (English)

    Jorge, González U; Pablo, Undurraga; Juan, Hirzel; Ingrid, Martínez G.

    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 beha [...] vior 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.

  6. Simulating Soil Moisture under Different Tillage Practices, Cropping Systems and Organic Fertilizers Using CropSyst Model, in Matuu Division, Kenya

    OpenAIRE

    Muli M. N.; Onwonga R. N.; Karuku G. N.; Kathumo V. M.; Nandukule M. O.

    2015-01-01

    Soil moisture stress is a limiting factor in crop production particularly in arid and semi-arid lands (ASALs) as it affects many physiological and biochemical processes of plants. Research on moisture conservation measures is thus imperative. The current study used CropSyst model to simulate soil moisture under different tillage practices (oxen plough, tied ridges and furrows and ridges), cropping systems (monocropping, intercropping and crop-rotation) and organic fertilizers; farm yard manur...

  7. Chiral symmetry in rotating systems

    Science.gov (United States)

    Malik, Sham S.

    2015-08-01

    The triaxial rotating system at critical angular momentum I ?Iband exhibits two enatiomeric (the left- and right-handed) forms. These enatiomers are related to each other through dynamical chiral symmetry. The chiral symmetry in rotating system is defined by an operator ? ˆ =Rˆy (?) T ˆ, which involves the product of two distinct symmetries, namely, continuous and discrete. Therefore, new guidelines are required for testing its commutation with the system Hamiltonian. One of the primary objectives of this study is to lay down these guidelines. Further, the possible impact of chiral symmetry on the geometrical arrangement of angular momentum vectors and investigation of observables unique to nuclear chiral-twins is carried out. In our model, the angular momentum components (J1, J2, J3) occupy three mutually perpendicular axes of triaxial shape and represent a non-planar configuration. At certain threshold energy, the equation of motion in angular momentum develops a second order phase transition and as a result two distinct frames (i.e., the left- and right-handed) are formed. These left- and right-handed states correspond to a double well system and are related to each other through chiral operator. At this critical angular momentum, the centrifugal and Coriolis interactions lower the barrier in the double well system. The tunneling through the double well starts, which subsequently lifts the degeneracy among the rotational states. A detailed analysis of the behavior of rotational energies, spin-staggering, and the electromagnetic transition probabilities of the resulting twin-rotational bands is presented. The ensuing model results exhibit similarities with many observed features of the chiral-twins. An advantage of our formalism is that it is quite simple and it allows us to pinpoint the understanding of physical phenomenon which lead to chiral-twins in rotating systems.

  8. Controle de doenças de plantas pela rotação de culturas / Control of plant disease by crop rotation

    Scientific Electronic Library Online (English)

    Erlei Melo, Reis; Ricardo Trezzi, Casa; Vânia, Bianchin.

    2011-09-01

    Full Text Available Esta revisão aborda a importância da escolha e da adoção de práticas culturais e seus reflexos na intensidade de doenças de plantas. São apresentados conceitos básicos referente ao tema e os de rotação e monocultura. Discutem-se os princípios ou fundamentos e potencialidade do uso da rotação e do ma [...] nejo integrado de doenças, as consequências da nutrição de fitopatógenos, dos eventos biológicos ocorrentes nos restos culturais, as características dos fitopatógenos potencialmente controláveis e dos não controláveis pela rotação. Abstract in english This review deals with the importance of the selection and use of cultural practices and their reflex in plant disease intensity. Basic concepts related to the subject and crop rotation and monoculture are presented. Principles fundaments are discussed in addition to, the potential use of crop rotat [...] ion integrated disease management. The consequences of plant pathogens nutrition, biological events in crop residues, characteristics of phytopathogens potentially controlled and not controlled by rotation are also dealt.

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

    Directory of Open Access Journals (Sweden)

    Asker U. Taychibekov

    2012-09-01

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

  10. Influence of Rotation Crops on the Strawberry Pathogens Pratylenchus penetrans, Meloidogyne hapla, and Rhizoctonia fragariae.

    Science.gov (United States)

    Lamondia, J A

    1999-12-01

    Field microplot, small plot, and greenhouse experiments were conducted to determine the effects of rotation crops on Pratylenchus penetrans, Meloidogyne hapla, and Rhizoctonia fragariae populations. Extraction of P. penetrans from roots and soil in microplots and field plots planted to rotation crops was highest for Garry oat, lowest for Triple S sorgho-sudangrass and Saia oat, and intermediate for strawberry, buckwheat, and canola. Isolation of R. fragariae from bait roots was highest for strawberry and canola after 2 years of rotation and lowest for Saia oat. Nematode extraction from roots of rotation crops in field soils was generally higher than from roots in microplots. Grasses were nonhosts of M. hapla. Strawberry, canola, and buckwheat supported root-knot populations over time, but there were no differences in nematode numbers regardless of crop after one season of strawberry growth. Garry oat, canola, and, to a lesser extent, buckwheat supported large populations of P. penetrans without visible root symptoms. Strawberry plants supported fewer nematodes due to root damage. Nematode numbers from soil were less than from roots for all crops. While there were similar trends for pathogen recovery after more than 1 year of strawberry growth following rotation, differences in pathogen density and fruit yield were not significant. In the greenhouse, P. penetrans populations in roots and soil in pots were much higher for Garry oat than for Saia oat. Total P. penetrans adult and juvenile numbers per pot ranged from 40 to 880 (mean = 365.6) for Garry oat and 0 to 40 (mean = 8.7) for Saia oat. Production of Saia oat as a rotation crop may be a means of managing strawberry nematodes and black root rot in Connecticut. PMID:19270931

  11. Effects of contrasting catch crops on nitrogen availability and nitrous oxide emissions in an organic cropping system

    DEFF Research Database (Denmark)

    Li, Xiaoxi; Petersen, SØren O

    2015-01-01

    Legume-based catch crops (LBCCs) may act as an important source of nitrogen (N) in organic crop rotations because of biological N fixation. However, the potential risk of high nitrous oxide (N2O) emissions needs to be taken into account when including LBCCs in crop rotations. Here, we report the results from a one-year field experiment, which investigated N availability and N2O emissions as affected by three LBCCs, i.e., red clover (CL), red clover–ryegrass mixture (GC) and winter vetch (WV), two non-LBCCs, i.e., perennial ryegrass (GR) and fodder radish (FR), and a control (CO) without catch crops. The effect of two catch crop management strategies was also tested: autumn harvest of the catch crop versus incorporation of whole-crop residues by spring ploughing. LBCCs accumulated 59–67 kg N ha?1 in their tops, significantly more than those of the non-LBCC, 32–40 kg N ha?1. Macro-roots accounted for >33% of total N in the catch crops. In accordance with this, LBCCs enhanced the performance of the succeeding unfertilised spring barley, thus obtaining a grain yield of 3.3–4.5 Mg ha?1 compared to 2.6–3.3 Mg ha?1 grain yield from non-LBCC and the fallow control treatments. Autumn harvest of catch crops, especially LBCCs, tended to reduce crop yield. The annual N2O emissions were comparable across treatments except for fodder radish, which had the highest N2O emission, and also the highest average yield-scaled N2O emission, at 499 g N2O-N Mg?1 grain. Although the sampling strategy employed in this study introduces uncertainty about the spatial and temporal variability, differences in seasonal emission patterns among catch crops were captured and harvest of catch crops in late autumn induced significantly higher emissions during winter, but lower emissions after residue incorporation in spring. In comparison with non-LBCC, LBCCs have the potential to partly replace the effect of manure application in organic cropping systems with greater crop production and less environmental footprint with respect to N2O emissions. However, harvest of the catch crops may reduce crop yield unless the harvested N is recycled as fertiliser to the crops in the rotation.

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

    DEFF Research Database (Denmark)

    Chirinda, Ngoni; Carter, Mette Sustmann; Alberg, Kristian R; Ambus, Per; Olesen, Jørgen E; Porter, John Roy; Petersen, Søren O

    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. The main objective of this study was to compare nitrous oxide (N2O) emissions from soil under winter wheat (Triticum aestivum L.) within three organic and one conventional cropping system that differed in...

  13. Development of rotation sample designs for the estimation of crop acreages

    Science.gov (United States)

    Lycthuan-Lee, T. G. (principal investigator)

    1981-01-01

    The idea behind the use of rotation sample designs is that the variation of the crop acreage of a particular sample unit from year to year is usually less than the variation of crop acreage between units within a particular year. The estimation theory is based on an additive mixed analysis of variance model with years as fixed effects, (a sub t), and sample units as a variable factor. The rotation patterns are decided upon according to: (1) the number of sample units in the design each year; (2) the number of units retained in the following years; and (3) the number of years to complete the rotation pattern. Different analytic formulae for the variance of (a sub t) and the variance comparisons in using a complete survey of the rotation patterns.

  14. 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

    Scientific Electronic Library Online (English)

    Elcio Liborio, Balota; Miriam, Kanashiro; Arnaldo, Colozzi Filho; Diva Souza, Andrade; Richard Peter, Dick.

    2004-12-01

    Full Text Available 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 agric [...] ultura 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 do solo (plantio direto ou convencional) nas parcelas e a rotação de culturas (soja/trigo, milho/trigo e algodão/trigo) nas subparcelas. Amostras de solos foram coletadas a 0-5, 5-10 e 10-20 cm de profundidade em 1997 e 1998. Na profundidade de 0-5 cm sob PD, observaram-se aumentos de 68% na atividade da amilase, 90% na celulase, 219% na arilsulfatase, 46% na fosfatase ácida e 61% na fosfatase alcalina. Observaram-se correlações significativas entre a atividade enzimática e o C-orgânico total do solo e o C e N da biomassa microbiana. Esses resultados evidenciam que a atividade enzimática do solo é um indicador sensível de alterações na qualidade do solo, promovidas pelo manejo. Abstract in english 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 p [...] rovide 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.

  15. Effect of Crop Rotation on Meloidogyne spp. and Pratylenchus spp. Populations in Strawberry Fields in Taiwan

    OpenAIRE

    Chen, P.; Tsay, T. T.

    2006-01-01

    Changes in population levels of Meloidogyne hapla, M. incognita, Pratylenchus coffeae, and P. penetrans were studied in 12 strawberry fields in the Dahu region of Taiwan. Ten potential rotation crops and two cultural practices were evaluated for their effect on nematode populations and influence on strawberry yield. Rotation with rice or taro and the cultural practice of flooding and bare fallowing for four months were found to reduce nematode soil populations to two or fewer nematodes per 10...

  16. 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 experiment where four N fertigation levels were applied to a bell pepper-cauliflower-Swiss chard rotation in a sandy loam soil. All the input data were obtained from measurements, transfer functions or were i...

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

    DEFF Research Database (Denmark)

    Petersen, SØren O; SchjØnning, Per

    2013-01-01

    In organic cropping systems, legumes, cover crops (CC), residue incorporation, and manure application are used to maintain soil fertility, but the contributions of these management practices to soil nitrogen (N) supply remain obscure. We examined potential sources of N for winter wheat (Triticum aestivum L.) in four experimental cropping systems established in 1997 on three soil types. Three of the four systems were under organic management. Topsoil N, depth of the A horizon, and cumulated inputs of N since 1997 were determined at plot level. Labile soil N pools [mineral N, potentially mineralizable N (PMN), microbial biomass N (MBN)] were monitored during two growth periods; at one site, biomass C/N ratios were also determined. Soil for labile N analysis was shielded from N inputs during spring application to isolate cumulated system effects. Potentially mineralizable N and MBN were correlated across all sites and rotations (r2 = 0.72). The MBN corresponded to 46 to 85, 85 to 145, and 74 to 172 kg N ha?1 at the three sites and differed significantly between cropping systems, but MBN could not explain differences in wheat grain N yields. Instead, a multiple linear regression model explained 76 and 82% of the variation in grain N yields in organic cropping systems in 2007 and 2008, showing significant effects of, respectively, topsoil N, depth of A horizon, cumulated inputs of N, and N applied to winter wheat in manure. Thus, soil properties and past and current management all contributed to winter wheat N supply.

  18. Water extractable organic carbon and nitrogen affected by crop rotation and fertilizer management

    Science.gov (United States)

    The importance of soil water soluble organic matter on soil and its environment has been recognized. In this chapter, the role of soil water soluble organic C and N in crop rotation and fertilizer N management has been demonstrated in two cases. For the case of double (potato/barley) and triple cr...

  19. Will breeding for nitrogen use efficient crops lead to nitrogen use efficient cropping systems? : a simulation study of GxExM interactions

    DEFF Research Database (Denmark)

    DresbØll, Dorte Bodin; Thorup-Kristensen, Kristian

    2014-01-01

    The benefits of improving nitrogen use efficiency (NUE) in crops are typically studied through the performance of the individual crop. However, in order to increase yields in a sustainable way, improving NUE of the cropping systems must be the aim. We did a model simulation study to investigate how improvement of NUE traits of individual crops affects the succeeding crops and the NUE of the crop rotation. Based on experimental results parameterization was altered for different types of improved NUE in the EU-Rotate_N model, e.g. through higher N harvest index, reduced litter loss or improved root depth penetration rate. The different ways of improving NUE have different effects on the cropping system, affecting either N uptake, the ability of the crop to hold on to N already taken up, or the fraction of crop N being harvested. Due to the different modes of action, the model simulations show that these changes in NUE traits will also have different effects on N leaching loss and on N availability and N loss in the following years. Simulations also show that the effect of genotypes with improved NUE depend on environment and crop management. This is true for the improved crop itself and when its effect is analyzed for the whole cropping system. The environmental conditions, crop choices and management will all affect the fate of the N left in the soil, and whether this will contribute mainly to leaching loss or be used for production in later crops. As an example, increasing pre-crop fertilization was shown to affect the leaching after the following oilseed rape crop with up to 50 kg N ha?1 taken up before it was lost to the environment when pre-crop fertilization as well as root depth penetration rate was high. All in all, the simulations illustrate the concept of NUE as the result of interactions between genotype, environment and crop management (G×E×M).

  20. Long-term C-CO2 emissions and carbon crop residue mineralization in an oxisol under different tillage and crop rotation systems / Emissões deC-CO2 de longo prazo e a mineralização do carbono dos resíduos culturais em um latossolo sob diferentes sistemas de preparo e rotação de culturas

    Scientific Electronic Library Online (English)

    Ben-Hur Costa de, Campos; Telmo Jorge Carneiro, Amado; Carlos Gustavo, Tornquist; Rodrigo da Silveira, Nicoloso; Jackson Ernani, Fiorin.

    2011-06-01

    Full Text Available A emissão de C-CO2 do solo é considerada um indicador sensível dos impactos de sistemas de manejo sobre a matéria orgânica do solo (MOS). Nos sistemas agrícolas, as principais fontes de C-CO2 são as decomposições dos resíduos culturais e da MOS, além da respiração das raízes das culturas e da biota [...] do solo. O principal objetivo deste estudo foi avaliar o impacto de sistemas de preparo do solo e culturas nas emissões de longo prazo de C-CO2 do solo e sua relação com a mineralização do carbono (C) de resíduos culturais. Este estudo foi desenvolvido em experimento de longa duração, em Latossolo Vermelho distrófico típico, de ocorrência na região de Cruz Alta, RS, Brasil. O clima é o subtropical Cfa, segundo a classificação de Köppen, com precipitação pluvial anual média de 1.744 mm e temperatura média anual de 19,2 ºC. Os tratamentos investigados foram dois sistemas de preparo - convencional (PC) e plantio direto (PD) - e três sistemas de culturas: R0- sucessão de monoculturas (trigo/soja); R1- rotação de culturas de inverno (aveia-preta/soja/trigo/soja); e R2- rotação intensiva de culturas (aveia-preta/soja/aveia-preta+ervilhaca/milho /nabo forrageiro/trigo/soja). O efluxo de C-CO2 do solo foi avaliado em intervalos fixos de 14 dias, durante dois anos (48 avaliações), por meio da captura do dióxido de carbono em solução alcalina. A umidade gravimétrica do solo, na camada de 0-0,05 m, foi determinada concomitantemente com as medições de C-CO2. Ainda, foi avaliada a taxa de liberação do C dos resíduos culturais utilizando o método dos sacos de decomposição, com amostragens aos 14, 28, 56, 84, 112 e 140 dias após o início das avaliações de mineralização do C. Foram utilizados quatro índices de conservação do C para avaliar a relação entre as emissões de C-CO2 e estoques de C e seus compartimentos no solo. A mineralização do C dos resíduos culturais no tempo seguiu o modelo exponencial. Para os resíduos de aveia-preta, trigo e milho, a mineralização do C foi maior no CT do que no PD, enquanto para a soja foi semelhante entre os sistemas de preparo do solo. A umidade do solo foi maior sob PD do que no PC, especialmente no segundo ano de avaliação. Não houve diferença na emissão média anual de C-CO2 entre sistemas de preparo; diferenças foram observadas apenas em algumas avaliações individuais. As emissões de C-CO2 seguiram padrão bimodal, com picos nos meses de outubro-novembro e fevereiro-março. As maiores emissões de C-CO2 foram registradas no verão, e as menores, no inverno. As emissões de C-CO2 apresentaram baixa correlação com a temperatura do ar e não foram influenciadas pela umidade do solo. Com base nos índices de conservação de C investigados, o PD associado à rotação intensiva de culturas foi mais conservador de C do que o PC com sucessão de culturas. Abstract in english 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 evaluat [...] e 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 a

  1. 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

    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” where plant material from grass-clover cuts was left in the field to decompose and no fertilizer or manure was applied to any crop in the rotation; and “+M” where plant material from grass-clover cuts was harvested and equivalent amounts of N in digested manure used for fertilization of cash crops 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 little or no effect on N2O emissions. Periods of high N2O emissions coincided with cover crop and grass-clover residue turnover, with little added effect of digested manure application. Annual N2O emissions did not vary between fertilization treatments, but the +M treatment had cash crop dry matter yields that were 14% higher than in the ?M treatment, and cash crop N yields were increased by 40%. The results show that reallocation of nutrients from grass-clover to cash crops following anaerobic digestion can help solve problems with low N availability. However, issues remain regarding N2O from cover crops and grass-clover in spring.

  2. 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; Olesen, Jørgen E

    2015-01-01

    N concentration for winter and spring cereals, respectively, and 68% and 77% of the variation in the square root transform of annual NO3single bondN leaching for winter and spring cereals, respectively. Nitrate concentration and leaching were shown to be site specific and driven by climatic factors and crop......The effect of variation in seasonal temperature and precipitation on soil water nitrate (NO3single bondN) concentration and leaching from winter and spring cereals cropping systems was investigated over three consecutive four-year crop rotation cycles from 1997 to 2008 in an organic farming crop...... rotation experiment in Denmark. Three experimental sites, varying in climate and soil type from coarse sand to sandy loam, were investigated. The experiment included experimental treatments with different rotations, manure rate and cover crop, and soil nitrate concentrations was monitored using suction...

  3. Dinâmica da agregação de um solo franco-arenoso em cinco sistemas de culturas em rotação e em sucessão / Aggregation dynamics of a sandy soil under five cropping systems in rotation and in succession

    Scientific Electronic Library Online (English)

    E. V., Wohlenberg; J. M., Reichert; D. J., Reinert; E., Blume.

    2004-10-01

    Full Text Available Espécies de cobertura, aliadas a práticas de manejo e conservação, recuperam ou mantêm características físicas do solo como a agregação. O objetivo deste trabalho foi determinar, ao longo do tempo, a influência de sistemas de culturas, de cobertura do solo e do teor de matéria orgânica sobre a agreg [...] ação de um Argissolo Vermelho-Amarelo distrófico arênico em seu estado natural e sob rotação e sucessão de culturas. O estudo foi realizado na área experimental do Departamento de Solos da UFSM, em Santa Maria (RS). Amostras indeformadas, coletadas em intervalos de 60 dias, de outubro de 1997 a outubro de 1998, na profundidade de 0-0,05 m, foram analisadas quanto à estabilidade de agregados, teor de C orgânico e outros atributos físicos e químicos. A maior estabilidade estrutural ocorreu no solo sob campo natural e a menor em solo descoberto, em virtude do intenso preparo do solo e da redução do teor de matéria orgânica, aumentando os agregados de menor tamanho. Existe uma ação direta das culturas na formação e estabilização dos agregados, sendo a estabilidade e a distribuição do tamanho de agregados maiores em sistemas de cultivo que aportam material orgânico e cobrem o solo durante todo o ano. As seqüências de culturas influem diferenciadamente na agregação do solo, dependendo da época do ano e tempo de estabelecimento dos sistemas de culturas. Abstract in english Cover crops along with proper soil management recover or maintain soil physical properties such as aggregation. The objective of this study was to determine the effect of cropping systems, cover crops, and soil organic matter (SOM) content on the temporal variation of soil aggregation in an Hapludal [...] f in its natural state and under different cropping systems. The experiment was conducted at the experimental station of the Soil Department of the UFSM, Brazil. Undisturbed soil samples were collected in 60 day-intervals throughout an year (Ocotober/1997 to October/1998) from a depth of 0-0.05 m and analyzed for aggregate stability, SOM content, and selected physical and chemical properties. The greatest structural stability was observed under grassland and the smallest stability for bare soil due to the intense soil tillage and reduction in SOM, increasing the proportion of small aggregates. Cover crops formed and stabilized soil aggregates directly, and the stability and proportion of aggregates were greater under cultivation systems that increase SOM and cover the soil during the whole year. Different cropping sequences affect soil aggregation distinctly, depending on the time of the year and time of establishment of the crops.

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

    OpenAIRE

    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 lengt...

  5. Self-seeding small grain cover crops in a soybean-corn rotation

    Science.gov (United States)

    Cover crops provide environmental benefits, yet adoption in agronomic farming systems is low. Winter rye (Secale cereale L.), wheat (Triticum aestivum L.), and triticale (X Triticosecale Wittmack) were used to develop self-seeding cover crop systems in a soybean [Glycine max (L.) Merr.]-corn (Zea m...

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

    DEFF Research Database (Denmark)

    Rasmussen, Ilse A.; Melander, Bo

    2014-01-01

    Elytrigia repens is a noxious perennial weed in organic cropping systems in Scandinavia. It can easily spread in any crop type and reach unacceptable infestation levels through its proliferation from rhizome fragments. This study aimed at analyzing and quantifying the population dynamics of E. repens recorded in a long-termed crop rotation experiment on coarse sand in Southern Denmark. The study gives an insight into the factors responsible for E. repens population changes and especially those that require particular attention to prevent outbreaks of E. repens. Data originated from three 4-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’ not in the last course) and with and without catch crops. E. repens was controlled by different tillage tactics and mowing strategies between and within crops and were conducted whenever the population had exceeded certain thresholds. Pulses, either in pure stands or in mixtures with spring barley, and spring cereals (barley and wheat) caused the highest population increases (up to eightfold), especially when preceded by grass-clover. Winter rye and potatoes with ridging cultivations were neutral to the E. repens population. Cultivations between crops were necessary to diminish the infestation and were the main reason for lower infestations in treatments without catch crops. Manuring resulted in a general reduction of E. repens by 28 % when analyzing data from all three courses. The study has identified the crop types that need particular attention when designing crop sequences, the importance of sufficient nutrients supplies to strengthen crop suppression of weeds and the need for mechanical interventions to mange E. repens satisfactorily.

  7. Effects of crop rotation, tillage, and fertilizer applications on sorghum head insects.

    Science.gov (United States)

    Chilcutt, Charles F; Matocha, John E

    2007-02-01

    Rotations, tillage, and fertilizer treatments can affect yield, costs, and profitability in sorghum, Sorghum bicolor (L.) Moench, depending on their effects on pests. Rotation or planting different crops reduces soil erosion and pests that build up when a field is planted to the same crop each year. Minimum tillage reduces the number of trips over a field, lessening soil compaction and reducing costs. We examined the effects of fertilizer, tillage, and rotation with cotton, Gossypium hirsutum L., on sorghum head insects during three sampling periods each year from 2000 to 2003. We found that fertilizer treatments did not affect pests or predators. Also, predators were unaffected by rotation and tillage, which some years affected Helicoverpa zea (Boddie) and Oebalus pugnax (F.), both pests that feed on developing sorghum kernels, thereby reducing yield. In 2000, H. zea densities were greater in continuous sorghum, regardless of tillage practice, than in sorghum-cotton rotation. However, in 2003, H. zea densities were greater in minimum tillage plots within sorghum- cotton rotation than minimum tillage plots within continuous sorghum. In 2000, in sorghum- cotton rotation, O. pugnax densities were greater in minimum tillage than conventional tillage plots, whereas in continuous sorghum the opposite was true, O. pugnax were greater in conventional tillage. Also, O. pugnax were greater in sorghum- cotton rotation than in continuous sorghum. In 2002, O. pugnax densities were greater in conventional than minimum tillage plots. These results suggest that rotation of sorghum with cotton can sometimes reduce H. zea, but this reduction may occur with increased density of O. pugnax. Also, reducing tillage may reduce O. pugnax in some instances. PMID:17370814

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

    Science.gov (United States)

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

    2006-09-01

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

  9. Long-Term Effect of Crop Rotation and Fertilisation on Bioavailability and Fractionation of Copper in Soil on the Loess Plateau in Northwest China.

    Science.gov (United States)

    Zang, Yifei; Wei, Xiaorong; Hao, Mingde

    2015-01-01

    The bioavailability and fractionation of Cu reflect its deliverability in soil. Little research has investigated Cu supply to crops in soil under long-term rotation and fertilisation on the Loess Plateau. A field experiment was conducted in randomized complete block design to determine the bioavailability and distribution of Cu fractions in a Heilu soil (Calcaric Regosol) after 18 years of rotation and fertilisation. The experiment started in 1984, including five cropping systems (fallow control, alfalfa cropping, maize cropping, winter wheat cropping, and grain-legume rotation of pea/winter wheat/winter wheat + millet) and five fertiliser treatments (unfertilised control, N, P, N + P, and N + P + manure). Soil samples were collected in 2002 for chemical analysis. Available Cu was assessed by diethylene triamine pentaacetic acid (DTPA) extraction, and Cu was fractionated by sequential extraction. Results showed that DTPA-Cu was lower in cropping systems compared with fallow control. Application of fertilisers resulted in no remarkable changes in DTPA-Cu compared with unfertilised control. Correlation and path analyses revealed that soil pH and CaCO3 directly affected Cu bioavailability, whereas available P indirectly affected Cu bioavailability. The concentrations of Cu fractions (carbonate and Fe/Al oxides) in the plough layer were lower in cropping systems, while the values in the plough sole were higher under grain-legume rotation relative to fallow control. Manure with NP fertiliser increased Cu fractions bound to organic matter and minerals in the plough layer, and its effects in the plough sole varied with cropping systems. The direct sources (organic-matter-bound fraction and carbonate-bound fraction) of available Cu contributed much to Cu bioavailability. The mineral-bound fraction of Cu acted as an indicator of Cu supply potential in the soil. PMID:26694965

  10. 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

    2013-01-01

    Noninversion 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 might hinder further expansion of reduced-tillage systems. European agriculture is asked to become less dependent on pesticides and promote crop protection programs based on integrated pest management (IPM) principles. Conventional noninversion tillage systems rely entirely on the availability of glyphosate products, and herbicide consumption is mostly higher compared to plow-based cropping systems. Annual grass weeds and catchweed bedstraw often constitute the principal weed problems in noninversion tillage systems, and crop rotations concurrently have very high proportions of winter cereals. There is a need to redesign cropping systems to allow for more diversification of the crop rotations to combat these weed problems with less herbicide input. Cover crops, stubble management strategies, and tactics that strengthen crop growth relative to weed growth are also seen as important components in future IPM systems, but their impact in noninversion tillage systems needs validation. Direct mechanical weed control methods based on rotating weeding devices such as rotary hoes could become useful in reduced-tillage systems where more crop residues and less workable soils are more prevalent, but further development is needed for effective application. Owing to the frequent use of glyphosate in reduced-tillage systems, perennial weeds are not particularly problematic. However, results from organic cropping systems clearly reveal that desisting from glyphosate use inevitably leads to more problems with perennials, which need to be addressed in future research.

  11. 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 autotrophic component (65% of TER and more). Autotrophic respiration was closely related to GPP during the growth period. The main causes of uncertainty with these results were due to biomass samplings and eddy covariance measurements (mainly, uncertainties about the u* threshold determination).

  12. Short-rotation woody crops for bioenergy and biofuels applications

    OpenAIRE

    Hinchee, Maud; Rottmann, William; Mullinax, Lauren; Zhang, Chunsheng; Chang, Shujun; Cunningham, MIchael; Pearson, Leslie; Nehra, Narender

    2009-01-01

    Purpose-grown trees will be part of the bioenergy solution in the United States, especially in the Southeast where plantation forestry is prevalent and economically important. Trees provide a “living biomass inventory” with existing end-use markets and associated infrastructure, unlike other biomass species such as perennial grasses. The economic feasibility of utilizing tree biomass is improved by increasing productivity through alternative silvicultural systems, improved breeding and biotec...

  13. 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.

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

    Scientific Electronic Library Online (English)

    Yinli, Liang; Caihong, Bai; Lan, Mu; Maojuan, Zhou.

    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.

  15. [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. PMID:26685595

  16. Soil water retention and s index after crop rotation and chiseling Retenção de água no solo e índice s influenciados por rotação de culturas e escarificação

    OpenAIRE

    Juliano Carlos Calonego,; Ciro Antonio Rosolem

    2011-01-01

    Soil compaction can be minimized either mechanically or biologically, using plant species with vigorous root systems. An experiment was carried out with soybean (Glycine max) in rotation with triticale (X Triticosecale) and sunflower (Helianthus annuus) in fall-winter associated with pearl millet (Pennisetum glaucum), grain sorghum (Sorghum bicolor) or sunn hemp (Crotalaria juncea) in spring. Crop rotation under no-till was compared with mechanical chiseling. The experiment was carried out in...

  17. Effects of crop rotation and nitrogen fertilization on soil nitrate and wheat yield under rainfed Mediterranean conditions

    OpenAIRE

    Rafael J. López-Bellido Garrido,; López-Bellido, Luis

    2001-01-01

    A field study was conducted from 1988 to 1998 to determine the effects of crop rotation and N fertilizer on wheat (Triticum aestivum L.) yield in a rainfed Vertisol Mediterranean region. Over the last 3 years of the study, the effect of crop rotation on residual soil NO$^-_3$-N before sowing and after wheat harvest was also examined. Crop rotations were wheat-sunflower, wheat-chickpea, wheat-faba bean, wheat-fallow and continuous wheat, with three different N fertilizer rates: 50, 100 and 150...

  18. Biogas from ley crops

    International Nuclear Information System (INIS)

    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

  19. Long-term effects of crop rotation and fertilizers on weed community in spring barley

    OpenAIRE

    CHAMANABAD, Hamid Reza Mohammaddoust; GHORBANI, Ardavan

    2009-01-01

    Integrated weed management programs require a clear understanding of the mechanisms influencing the establishment, growth, and reproduction of unwanted plants (weeds) in agro-ecosystems. This study evaluates the effect of long-term (95 years after the establishment of the site) crop rotation and chemical fertilizers on the weed community dynamics in spring barley at the Agricultural University of Timiriazev, Agricultural Site in Moscow. The weed community occurring on plots of spring barley (...

  20. ESTIMATION OF RESOURCE-HEALING ROLE LUPINE AND STRAW IN THE GRAIN-ROW CROP ROTATION

    OpenAIRE

    Tatyana ANISIMOVA

    2014-01-01

    In field experiences on soddy-podzolic sandy soil of Meshchersky lowland high agroeconomic efficiency of an adaptive link of a crop rotation with, grown up on grain, a potato and barley is established, at entering winter wheat straw under lupine . Straw in a combination with lupine has proved to be a perspective reserve of reproduction of fertility of soils without participation of nitrogen of mineral fertilizers.

  1. 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.

  2. ESTIMATION OF RESOURCE-HEALING ROLE LUPINE AND STRAW IN THE GRAIN-ROW CROP ROTATION

    Directory of Open Access Journals (Sweden)

    Tatyana ANISIMOVA

    2014-03-01

    Full Text Available In field experiences on soddy-podzolic sandy soil of Meshchersky lowland high agroeconomic efficiency of an adaptive link of a crop rotation with, grown up on grain, a potato and barley is established, at entering winter wheat straw under lupine . Straw in a combination with lupine has proved to be a perspective reserve of reproduction of fertility of soils without participation of nitrogen of mineral fertilizers.

  3. 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.

  4. 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; Schjønning, Per

    2010-01-01

    Organic and conventional farming practices differ in the use of several management strategies, including use of catch crops, green manure, and fertilization, which may influence soil properties, greenhouse gas emissions and productivity of agroecosystems. An 11-yr-old field experiment on a sandy...... loam soil in Denmark was used to compare several crop rotations with respect to a range of physical, chemical and biological characteristics related to carbon (C) and nitrogen (N) flows. Four organic rotations and an inorganic fertilizer-based system were selected to evaluate effects of fertilizer type...... growth was monitored and grain yields measured at harvest maturity. The different management strategies between 1997 and 2007 led to soil carbon inputs that were on average 18–68% and 32–91% higher in the organic than inorganic fertilizer-based rotations for the sampled winter wheat and spring barley...

  5. The Crop Growth Model in the Wind Erosion Prediction System

    Science.gov (United States)

    The primary purpose of the crop growth submodel (CROP) in the Wind Erosion Prediction System (WEPS) is to obtain realistic estimates of plant growth so that the influence of vegetative cover on wind erosion can be properly evaluated. Most crop growth models focus on estimating final crop yield. CROP...

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

    Directory of Open Access Journals (Sweden)

    P. Procha?zka

    2015-09-01

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

  7. Fission of rapidly rotating fluid systems

    International Nuclear Information System (INIS)

    Progress in understanding of the problem of fissional breakup of an equilibrium fluid system through the growth of dynamical distortional instabilities caused by rapid rotation is reviewed. Classic results on equilibrium states, stability, and routes to fission are reviewed, and the equilibrium states of uniformly rotating incompressible fluids, uniformly rotating polytropes, differentially rotating polytropes, rotating isothermal gas clouds, and nonisentropic fluids are discussed in detail. The Bardeen, Friedman, Schutz, and Sorkin (1977) criterion for linear stability in fission modes is considered along with the generic instability of rotating bodies and linear stability of fission modes in hydrodynamic simulations of fission are described in detail

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

    Directory of Open Access Journals (Sweden)

    Sophan Chhin

    2016-01-01

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

  9. 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: Elymus repens and Cirsium arvense.

  10. Predicting and mitigating the net greenhouse gas emissions of crop rotations in Western Europe

    OpenAIRE

    Lehuger, Simon; Gabrielle, Benoit; Laville, Patricia; Lamboni, Matieyendou; Loubet, Benjamin; Cellier, Pierre

    2011-01-01

    Nitrous oxide, carbon dioxide and methane are the main biogenic greenhouse gases (GHG) contributing to net greenhouse gas balance of agro-ecosystems. Evaluating the impact of agriculture on climate thus requires capacity to predict the net exchanges of these gases in a systemic approach, as related to environmental conditions and crop management. Here, we used experimental data sets from intensively-monitored cropping systems in France and Germany to calibrate and evaluate the ability of the ...

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

    OpenAIRE

    Lamberto Borrelli; Salvatore Colecchia; Antonio Troccoli; Sarah Caradonna; Rossella Papini; Domenico Ventrella; Maria Teresa Dell'Abate; Carlo Galeffi; Cesare Tomasoni; Roberta Farina

    2011-01-01

    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...

  12. Comportamento de Sternechus subsignatus (Boheman) em dez espécies vegetais de verão para rotação de culturas ou cultura armadilha no plantio direto / Sternechus subsignatus (Boheman) behaviour in ten summer rotation specles and trapping crops for no-tillage system

    Scientific Electronic Library Online (English)

    Mauro Tadeu Braga da, Silva.

    1997-12-01

    Full Text Available O desenvolvimento de Sternechus subsignatus (Boheman) (Coleoptera: Curculionidae) foi avaliado em dez espécies vegetais sob condições naturais num solo manejado há três anos no sistema de plantio direto corn soja cultivada no verão. Foram observados o número de plantas atacadas, a oviposição, o núrn [...] ero e peso de larvas, o número de larvas hibernantes no solo e o número de adultos emergidos. O inseto se reproduziu e desenvolveu ern feijão (Phaseolus vulgaris L) guandu anão (Cajanus cajan L), lab-lab (Dolichos lablab L.) e soja (Glycine max L.) e ao contrário, em crotalária júncea (Crotalaria júncea L). girassol (Helianthus annuus L.), milheto (Pennisetum americanum Leek), milho (Zea mays L), mucuna preta (Stizolobium aterrimum Piper et Tracy) e sorgo (Sorghum bicolor L.) não completou o ciclo de vida. Os resultados indicaram que a cultura do feijão, guandu anão, lab-lab e soja aumentaram a população do inseto. Entretanto, ocorreu redução na população do inseto corn as culturas da crotalária júncea, girassol, milheto, milho, mucuna preta e sorgo. As quatro primeiras espécies são hospedeiras preferenciais, podendo ser usadas como culturas armadilhas e as demais, não são hospedeiras, pois propiciam a diminuição da população do inseto, sendo ideais para uso em sistemas derotação de culturas no verão, em áreas infestadas, para substituir o monocultivo da soja em plantio direto. Abstract in english The development of Sternechus subsignatus (Boheman) (Coleoptera. Curculionidae) was evaluated on ten crop species under natural conditions under no-tillage system for three years and infested with the insect Soybean was the Summer crop continously cultivated in the area. Number of attacked plants, o [...] viposition, number and weight of larvae and number of adults emerged were the parameters evaluated. The insect reproduced and developed in bean (Phaseolus vulgaris L), grandull (Cajanus cajan L.), dolichos (Dolichos lablab L.) and soybean (Glycine max L.) and not in bengal hemp (Crotalaria júncea L ), sunflower (Helianthus annuus L.), millet (Pennisetum americanum Leek), corn (Zea mays L.), black velvet bean (Stizolobium aterrimum Piper et Tracy) and sorghum (Sorghum bicolor L.) did not complete lhe life cycle Results indicated that P. vulgaris, C. cajan, D. lablab and G. max increased insect populatron but, a reduction was observed on C. juncea, H. annuus, P. americanum, Z. mays, S. aterrimum and S. bicolor. The first four related species are the preferred hosts and may be used as trap crops. The other six species did not host the insect, decreasing its populations and thus being ideal to be included in Summer crop rotafion systems to subslitute soybean monocropping under no-tillage.

  13. Comportamento de Sternechus subsignatus (Boheman em dez espécies vegetais de verão para rotação de culturas ou cultura armadilha no plantio direto Sternechus subsignatus (Boheman behaviour in ten summer rotation specles and trapping crops for no-tillage system

    Directory of Open Access Journals (Sweden)

    Mauro Tadeu Braga da Silva

    1997-12-01

    Full Text Available O desenvolvimento de Sternechus subsignatus (Boheman (Coleoptera: Curculionidae foi avaliado em dez espécies vegetais sob condições naturais num solo manejado há três anos no sistema de plantio direto corn soja cultivada no verão. Foram observados o número de plantas atacadas, a oviposição, o núrnero e peso de larvas, o número de larvas hibernantes no solo e o número de adultos emergidos. O inseto se reproduziu e desenvolveu ern feijão (Phaseolus vulgaris L guandu anão (Cajanus cajan L, lab-lab (Dolichos lablab L. e soja (Glycine max L. e ao contrário, em crotalária júncea (Crotalaria júncea L. girassol (Helianthus annuus L., milheto (Pennisetum americanum Leek, milho (Zea mays L, mucuna preta (Stizolobium aterrimum Piper et Tracy e sorgo (Sorghum bicolor L. não completou o ciclo de vida. Os resultados indicaram que a cultura do feijão, guandu anão, lab-lab e soja aumentaram a população do inseto. Entretanto, ocorreu redução na população do inseto corn as culturas da crotalária júncea, girassol, milheto, milho, mucuna preta e sorgo. As quatro primeiras espécies são hospedeiras preferenciais, podendo ser usadas como culturas armadilhas e as demais, não são hospedeiras, pois propiciam a diminuição da população do inseto, sendo ideais para uso em sistemas derotação de culturas no verão, em áreas infestadas, para substituir o monocultivo da soja em plantio direto.The development of Sternechus subsignatus (Boheman (Coleoptera. Curculionidae was evaluated on ten crop species under natural conditions under no-tillage system for three years and infested with the insect Soybean was the Summer crop continously cultivated in the area. Number of attacked plants, oviposition, number and weight of larvae and number of adults emerged were the parameters evaluated. The insect reproduced and developed in bean (Phaseolus vulgaris L, grandull (Cajanus cajan L., dolichos (Dolichos lablab L. and soybean (Glycine max L. and not in bengal hemp (Crotalaria júncea L , sunflower (Helianthus annuus L., millet (Pennisetum americanum Leek, corn (Zea mays L., black velvet bean (Stizolobium aterrimum Piper et Tracy and sorghum (Sorghum bicolor L. did not complete lhe life cycle Results indicated that P. vulgaris, C. cajan, D. lablab and G. max increased insect populatron but, a reduction was observed on C. juncea, H. annuus, P. americanum, Z. mays, S. aterrimum and S. bicolor. The first four related species are the preferred hosts and may be used as trap crops. The other six species did not host the insect, decreasing its populations and thus being ideal to be included in Summer crop rotafion systems to subslitute soybean monocropping under no-tillage.

  14. 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. PMID:19274250

  15. Grass-clover undersowing affects nitrogen dynamics in a grain legume–cereal arable cropping system

    DEFF Research Database (Denmark)

    Hauggaard-Nielsen, Henrik; Mundus, Simon

    2012-01-01

    A field experiment was carried out in an arable organic cropping system and included a sequence with sole cropped fababean (Vicia faba L.), lupin (Lupinus angustifolius L.), pea (Pisum sativum L.), oat (Avena sativa L.) and pea–oat intercropping with or without an undersown perennial ryegrass (Lolium perenne L.) – white clover (Trifolium repens L.) catch crop followed by a first crop of spring wheat (Triticum aestivum L.) and second crop of winter triticale (Triticale hexaploide L.). The rotation sequence was repeated twice. Natural 15N abundance techniques were used to determine grain legume N2 fixation and 15N labeling technique to determine the fate of pea and oat residue N recovery in the subsequent crop. The subsequent spring wheat and winter triticale crop yields were not significantly affected by the previous main crop, but a significant effect of catch crop undersowing was observed. A higher soil mineral N content in the soil profile without undersown grass-clover increased the spring wheat yield. This effect was circumvented in the subsequent winter triticale, where yields in the treatments with catch crops undersown were significantly greater. The grass-clover catch crop after grain legumes had a higher grass proportion before incorporation as compared to grass-clover after oat, which had the greatest clover proportion. The dynamic response of interspecific interactions in the catch crop to the soil mineral N levels is moderating the preceding effect of main crops in the subsequent cereal – and sometimes to a higher degree than the main crop effect. For research involving rotation principles it is recommended to evaluate cumulative effects over several years and not only single seasons.

  16. Grass-clover undersowing affects nitrogen dynamics in a grain legume-cereal arable cropping system

    DEFF Research Database (Denmark)

    Hauggaard-Nielsen, Henrik; Mundus, Simon

    2012-01-01

    A field experiment was carried out in an arable organic cropping system and included a sequence with sole cropped fababean (Vicia faba L), lupin (Lupinus angustifolius L), pea (Pisum sativum L), oat (Avena sativa L) and pea-oat intercropping with or without an undersown perennial ryegrass (Lolium perenne L) - white clover (Trifolium repens L) catch crop followed by a first crop of spring wheat (Triticum aestivum L) and second crop of winter triticale (Triticale hexaploide L). The rotation sequence was repeated twice. Natural N-15 abundance techniques were used to determine grain legume N-2 fixation and N-15 labeling technique to determine the fate of pea and oat residue N recovery in the subsequent crop. The subsequent spring wheat and winter triticale crop yields were not significantly affected by the previous main crop, but a significant effect of catch crop undersowing was observed. A higher soil mineral N content in the soil profile without undersown grass-clover increased the spring wheat yield. This effect was circumvented in the subsequent winter triticale, where yields in the treatments with catch crops undersown were significantly greater. The grass-clover catch crop after grain legumes had a higher grass proportion before incorporation as compared to grass-clover after oat, which had the greatest clover proportion. The dynamic response of interspecific interactions in the catch crop to the soil mineral N levels is moderating the preceding effect of main crops in the subsequent cereal - and sometimes to a higher degree than the main crop effect. For research involving rotation principles it is recommended to evaluate cumulative effects over several years and not only single seasons.

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

    International Nuclear Information System (INIS)

    Nitrous oxide (N2O) and carbon dioxide (CO2) 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 N2O 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 N2O and CO2 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 N2O 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 N2O 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 N2O and CO2 were attributed to higher inorganic nitrogen (N) application rates in corn crops. In the corn phase, CO2 levels were higher when the preceding crop was winter wheat. It was concluded that N2O and CO2 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

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

    International Nuclear Information System (INIS)

    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

  19. Tropical annual cropping systems: Ant ecology

    Science.gov (United States)

    Carroll, C. Ronald; Risch, Stephen J.

    1983-01-01

    The ecological role of ants in tropical annual cropping systems is discussed in general and with respect to a specific Mexican agroecosystem Generally, the potential positive contributions of ants to crop yields result from their impact on soil structure, nutrient cycling, and reduction of insect and weed pests In annual wet lowland fields in eastern Mexico, the ant community is simple and dominated by the aggressive fire ant, Solenopsis geminata. The influence of vegetation structure and composition on the ant community and, specifically, on the foraging behavior of S geminata is discussed

  20. Sorbent-Bed Crop-Drying System

    Science.gov (United States)

    Roberts, Barry C.

    1992-01-01

    Proposed aeration system helps reduce spoilage of stored grain or other crop stored in bulk. Air circulates through bin, sorbent bed, and heat exchanger. Outside air cools circulating air in heat exchanger. Sensors measure temperature and humidity, and adjust dampers to obtain requisite temperature and humidity. Suitable for grain bins and shipping barges.

  1. Cooling system for rotating machine

    Science.gov (United States)

    Gerstler, William Dwight (Niskayuna, NY); El-Refaie, Ayman Mohamed Fawzi (Niskayuna, NY); Lokhandwalla, Murtuza (Clifton Park, NY); Alexander, James Pellegrino (Ballston Lake, NY); Quirion, Owen Scott (Clifton Park, NY); Palafox, Pepe (Schenectady, NY); Shen, Xiaochun (Schenectady, NY); Salasoo, Lembit (Schenectady, NY)

    2011-08-09

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

  2. Nitrogen management in organic farming: comparison of crop rotation residual effects on yields, N leaching and soil conditions

    OpenAIRE

    Kayser, Manfred; Müller, Jürgen; Isselstein, Johannes

    2009-01-01

    After 3 years of different crop rotations in an organic farming experiment on a sandy soil in northwest Germany, spring triticale was cultivated on all plots in the fourth year to investigate residual effects on yield, nitrogen (N) leaching and nutrient status in the soil. Previous crop rotations differed in the way N was supplied, either by farmyard manure (FYM, 100 and 200 kg N ha−1 year−1) or by arable legumes like grass-red clover and field beans, or as a control with no N. Other crops in...

  3. 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....... Accuracy of the predicted nitrate nitrogen (NO3-N) contents in the 0-90 cm soil profile was acceptable with both models, with values of the mean absolute error (MAE) below the average standard deviation of the observations. The uptake of nitrate was better simulated with EU-Rotate_N where specific crop N...... demand algorithms are involved. In the simulations with Hydrus-2D the evapotranspiration demand was a limiting factor for N uptake, resulting in an increasing underestimation of uptake with decreasing N fertilizer rates. Simulated N leaching below a depth of 60 cm was higher with Hydrus-2D due to a...

  4. Produção de trigo e triticale em rotações de sequeiro / Wheat and triticale in crop rotations

    Scientific Electronic Library Online (English)

    Carlos, Castro; João, Coutinho; Nuno, Moreira; António, Crespi.

    2008-01-01

    Full Text Available Apresentam-se os resultados de um ensaio de rotações que decorreu durante dez anos em Vila Real (Trás-os-Montes). O ensaio incluiu a rotação tradicional das condições de sequeiro de Trás-os-Montes, cereal-alqueive (TA), e rotações alternativas susceptíveis de serem adoptadas nestas condições, cereal [...] -leguminosa (TL), cereal-consociação forrageira (TC) e cereal-prado de sequeiro (TP). Os cereais das rotações foram o trigo e, posteriormente, o triticale. Determinaram-se e analisaram-se as produções de grão e palha, os teores de nutrientes do grão e da palha e acompanharam-se os parâmetros do solo, pH, matéria orgânica e os teores de P2 O 5, K2 O e bases de troca. Destacam-se alguns resultados importantes, tais como: as produções de grão de cereal das rotações não mostrarem diferenças significativas entre si; a produção de palha da rotação TL ser superior às das restantes; o trigo cultivado após prado de sequeiro não dispensar a adubação azotada; as rotações conduzirem a modificações dos teores de matéria orgânica, cálcio de troca ou do valor do pH do solo, factores a que se deve atender, caso a rotação se prolongue por muitos anos. Abstract in english The results of a field trial of crop rotations conducted over a period of ten years in Vila Real (Northeast Portugal) are presented. The rotations tested were cereal-cultivated fallow (TA), traditional in rain-fed conditions of the region, and alternative rotations that could be adopted in these con [...] ditions: cereal-grain legume crop (TL), cereal-forage mixture (TC) and cereal-rain-fed pasture (TP). The cereals were wheat and, later, triticale. Grain, straw and aerial biomass yields were evaluated together with concentrations of nutrients. The soil parameters studied were pH, organic matter and P 2 O 5, K2O and exchange cations. Wheat straw yield of TL rotation was higher than that of the others. Wheat from TP rotation still requires nitrogen fertilization. The soils of the different rotations registered changes of organic matter, Ca, Mg and pH values, which should be taken into account if these rotations are practised over several years.

  5. 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 at the study site, may better perform on marginal sites. Switchgrass is an example of the need to grow site-adapted energy crops. The annual energy crop maize required the highest input, but at the same time yielded the most. The two crop rotation systems did not differ in yield and energy input, but the system with no-till may be more environmentally benign as it has the potential to sequester carbon. The objective of Paper II was the optimization of crop cultivation through the differentiation of input parameters to enhance the quality of the energy crop triticale, without influencing the biomass yield. The intention was to minimize the content of combustion-disturbing elements (potassium and chlorine) and the ash residue of both aboveground plant parts (grain and straw). It was done through different straw and potassium fertilizer treatments. It could be shown that the removal of straw from the previously cultivated crop and no additional potassium fertilizer could reduce the amount of combustion-disturbing elements. A high influence must also be expected from site and weather conditions. Papers III to V address the supply of different high quality biomasses, with the focus on maize for anaerobic digestion. The objective of Paper III was the assessment of the requirements of biogas plants and biomass for anaerobic digestion. It introduces potential energy crops, along with their advantages and disadvantages. Alongside maize, many other biomass types, which are preserved as silage and are high in carbohydrates and low in lignocelluloses, can be anaerobically digested. The development of potential site-specific crop rotation systems for biomass production are discussed. The objective of Papers IV and V was the identification of suitable biomass and production systems for the anaerobic digestion. The focus lay on the determination of (i) suitable energy maize varieties for Central Europe, (ii) optimal growth periods of energy crops, (iii) the influence of crop management on quality parameters and (iv) environmentally benign crop rotation systems. Differently maturing maize varieties were grown in six different crop rotation systems (continuous maize with and without an undersown grass, maize as a main crop partially preceded by different winter catch crops and followed by winter wheat) and tested at two sites. Additional factors were sowing and/or harvest dates. Maize and cumulative biomass yields of the crop rotation systems were compared. Specific methane yield measurements were carried out to evaluate the energy performance of the tested crops. Quality was assessed either by measurements of the dry matter content or by using the near infrared reflectance spectroscopy for the determination of chemical composition. Results indicate that an environmentally benign crop rotation system requires nearly year-round soil cover to minimize nitrogen leaching. This can be achieved through the cultivation of undersown or catch crops and additional main crops alongside maize, such as winter wheat. Late maturing maize varieties can be cultivated at a site where the maize can build adequate dry matter contents due to a long growth period (late harvest date). The energy generation in terms of methane production was primarily dependent on high biomass yields. It could be further shown that the specific methane yield of maize increased with increasing starch content, digestibility and decreasing fiber content. To conclude, selected site-specific energy crops and crop rotation systems, with suitable crop management, (fertilizer and soil tillage) can produce high quality biomass and the highest net energy return. Lignocellulosic biomass can be optimized for combustion. Wet biomass is an optimal substrate for anaerobic digestion. Profitable energy production is characterized by a high land and energy use efficiency and especially high net energy yields. (orig.)

  6. Avaliação do potencial de coberturas verdes e de sitemas de rotações de cultura na supressão do nematoide anelado (Mesocriconema xenoplax em pré-plantio ao pessegueiro Evaluation of green covering potential and crop rotation systems in the suppression of the ring nematode (Mesocriconema xenoplax in peach pre-planting

    Directory of Open Access Journals (Sweden)

    Cesar Bauer Gomes

    2010-03-01

    Full Text Available Em uma área naturalmente infestada com o nematoide anelado (Mesocriconema xenoplax, coberturas verdes foram testadas quanto a sua hospedabilidade, em cultivos de inverno e verão, comparativamente às parcelas mantidas sob pousio. Três sistemas de rotação de culturas, com as mesmas espécies vegetais (aveia-preta/feijão-de-porco/milheto/nabo-forrageiro; nabo-forrageiro/milheto/aveia-branca/milho, e aveia-branca/mucuna-anã/trigo/sorgo, foram avaliados quanto ao potencial supressor do nematóide de M. xenoplax por dois anos, utilizando-se, como testemunhas, de parcelas mantidas sob pousio e alqueive. Os experimentos foram conduzidos a campo, em blocos ao acaso, com seis repetições. Antes e após o estabelecimento de cada cultivo, as populações do nematoide foram avaliadas quanto ao número de M. xenoplax/100cm³ de solo e fator de reprodução (FR= população final/população inicial do nematoide anelado, onde FR1,00, favorecimento da reprodução. A maioria das culturas testadas foi hospedeira desfavorável (FRIn a field naturally infested with ring nematode (Mesocriconema xenoplax, green covering were tested for their hostel in winter and summer crops comparing to plots kept in fallow lands. Tree crop rotation system with the same plant species (black oat/pig bean/ millet/forage radish; forage radish/ millet/white oat/corn; and white oat/mucuna deeringiana/wheat/sorghum were evaluated for suppression potential to nematode M. xenoplax for two years, using as witness plots that were kept in fallow lands. The experiments were conducted in the field in a randomized block design with six repetitions. Before and after the establishment of each plot, the nematode populations were evaluated on the number of M. xenoplax/100cm³ of soil and the reproduction factor (RF= final population/initial population of the ring nematode, where RF 1,00, favoring of the reproduction. Most of the crops analyzed were unfavorable host (RF<1,00 of M. xenoplax, except the mucuna deeringiana that behaved as favorable to the nematode reproduction. Although all treatments have removed M. xenoplax the crop rotations forage radish/ millet/white oat/corn and white oat/mucuna deeringiana/wheat/sorghum realized the largest reduction of the nematode in the soil (93-95%.It was noted a sharp decline in the M. xenoplax population in the first two crops, with later stabilization of its level, regardless of the studied system.

  7. Cropping Systems Dynamics in the Lower Gangetic Plains of India using Geospatial Technologies

    Directory of Open Access Journals (Sweden)

    K. R. Manjunath

    2012-08-01

    Full Text Available Cropping system study is useful to understand the overall sustainability of agricultural system. Capturing the change dynamics of cropping systems, especially spatial and temporal aspects, is of utmost importance in overall planning and management of natural resources. This paper highlights the remote sensing based cropping systems change-dynamics assessment. Current study is aimed at use of multidate-multisensor data for deriving the seasonal cropping pattern maps and deriving the remote sensing based cropping system performance indicators during 1998–99 and 2004–05 in West- Bengal state of India. The temporal assessment of the changes of cropping systems components such as cropping pattern and indices for the study years 1998–99 and 2004–05 have been brought out. The results indicate that during the six years of time the kharif cropping pattern has almost remained the same, being a rice dominant system. A notable point is the decrease in the aus rice due to readjusting the cropping system practice to suit the two crop systems in many places was observed. Marginal variations in mustard and wheat areas during rabi season was observed. The boro (summer rice area has almost remained constant. The rice-fallow-fallow (R-F-F rotation reduced by about 4 percent while the rice-fallow-rice (R-F-R increased by about 7 percent percent. The Area Diversity Index reduced by about 38 percent in 2004 which may be attributed to decrease in kharif pulses and minor crops during kharif and summer. However, diversity during rabi season continued to remain high. The increase in Multiple Cropping Index was observed predominantly in the southern part of the state. Cultivated Land Utilization Index shows an increase by about 0.05.

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

    Directory of Open Access Journals (Sweden)

    Laura Agneessens

    2014-12-01

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

  9. AGRONOMY AND PHYSIOLOGY OF TROPICAL COVER CROPS

    Science.gov (United States)

    Cover crops are important components of a sustainable crop production system. They can be planted with plantation crops such as cacao, coffee, banana, rubber and oil palm or in rotation with cash crops. Their use in a cropping system is mainly beneficial for soil and water conservation, recycling of...

  10. Stability of rotating spherical stellar systems

    OpenAIRE

    Alimi, J. -M.; Perez, J.; Serna, A.

    1999-01-01

    We study the stability of rotating collisionless self-gravitating spherical systems by using high resolution N-body experiments on a Connection Machine CM-5. We added rotation to Ossipkov-Merritt (hereafter OM) anisotropic spherical systems by using two methods. The first method conserves the anisotropy of the distribution function defined in the OM algorithm. The second method distorts the systems in velocity space. We then show that the stability of systems depends both on their anisotropy ...

  11. Work and energy in rotating systems

    OpenAIRE

    Manjarres, Diego A.; Herrera, William J.; Diaz, Rodolfo A.

    2012-01-01

    Literature analyzes the way in which Newton's second law can be used when non-inertial rotating systems are used. However, the treatment of the work and energy theorem in rotating systems is not considered in textbooks. In this paper, we show that the work and energy theorem can still be applied to a closed system of particles in a rotating system, as long as the work of fictitious forces is properly included in the formalism. The coriolis force does not contribute to the wo...

  12. Conservation tillage, rotations, and cover crop affect soil quality in the Tennessee Valley: Particulate organic matter, organic matter, and microbial biomass

    Science.gov (United States)

    Monocropping cotton (Gossypium hirsutum L.) with conventional tillage provides little carbon input to soil, increases erosion and promotes rapid oxidation of existing soil organic carbon (SOC). Management practices like conservation tillage, crop rotation, and cover cropping can impact soil carbon, ...

  13. ENERGY AND CARBON BUDGETS IN TRANSITIONAL CROPPING SYSTEMS IN MINNESOTA

    Science.gov (United States)

    Energy and carbon budgets were constructed for a wide range of cropping systems during the transition from conventional cropping practices. Cropping system treatments included factorial combinations of: conventional and organic systems (CNV and ORG), conventional tillage and strip tillage (CT and ST...

  14. A rotating target wheel system for gammasphere

    International Nuclear Information System (INIS)

    A description is given for a low-mass, rotating target wheel to be used within the Gammasphere target chamber. This system was developed for experiments employing high beam currents in order to extend lifetimes of targets using low-melting point target material. The design is based on a previously successful implementation of rotating target wheels for the Argonne Positron Experiment (APEX) as well as the Fragment Mass Analyser (FMA) at ATLAS (Argonne Tandem Linac Accelerator System). A brief history of these rotating target wheel systems is given as well as a discussion on target preparation and performance

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

    DEFF Research Database (Denmark)

    Jabloun, Mohamed; Schelde, Kirsten

    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 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 cups. The effects of climate, soil and management were examined in a linear mixed model, and only parameters with significant effect (P < 0.05) were included in the final model. The model explained 61% and 47% of the variation in the square root transform of flow-weighted annual NO3single bondN concentration for winter and spring cereals, respectively, and 68% and 77% of the variation in the square root transform of annual NO3single bondN leaching for winter and spring cereals, respectively. Nitrate concentration and leaching were shown to be site specific and driven by climatic factors and 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 that the predicted N concentration and leaching increased with increases in temperature and precipitation.

  16. Effects of Tillage, Rotation and Cover Crop on the Physical Properties of a Silt-Loam Soil

    Science.gov (United States)

    Haruna, Samuel Idoko; Nkongolo, Nsalambi Vakanda

    2015-04-01

    Soil and crop management practices can affect the physical properties and have a direct impact on soil sustainability and crop performance. The objective of this study was to investigate how soil physical properties were affected by three years of tillage, cover crop and crop rotation treatments in a corn and soybean field. The study was conducted on a Waldron siltyloam soil at Lincoln University of Missouri. Soil physical properties studied were soil bulk density, volumetric and gravimetric water contents, volumetric air content, total pore space, air-filled and water-filled pore space, gas diffusion coefficient and pore tortuosity factor. Results showed significant interactions (pimproved soil physical properties better in rotation than in monoculture.

  17. Effects of biophysical interactions of the alley cropping system on yield and nutrition of forage crops in Saskatchewan

    OpenAIRE

    Issah, G.; Kimaro, A.A.; Kort, J.; Knight, D. J.

    2014-01-01

    Competition between trees and crops in alley cropping systems for soil moisture, light and nutrients, especially N can lead to decreased crop yield. However, there is tree-crop interactions in alley cropping the Canadian prairies are poorly understood. This study examined the effects of light and soil moisture conditions in the alleyways on yield and nutrition of forage crops. The experiment was conducted using a 9-yeald old Manitoba maple alley cropping site with oats inter-planted in the al...

  18. Scientific Basis for Sustainable Management of Eucalyptus and Populus as Short-Rotation Woody Crops in the U.S.

    OpenAIRE

    Eric D. Vance; Craig Loehle; T. Bently Wigley; Philip Weatherford

    2014-01-01

    Short rotation woody crops (SRWC), fast growing tree species that are harvested on short, repeated intervals, can augment traditional fiber sources. These crops have economic and environmental benefits stemming from their capability of supplying fiber on a reduced land base in close proximity to users and when sensitive sites cannot be accessed. Eucalyptus and Populus appear to be genera with the greatest potential to provide supplemental fiber in the U.S. Optimal productivity can be achieved...

  19. Measurement of unsteady pressures in rotating systems

    Science.gov (United States)

    Kienappel, K.

    1978-01-01

    The principles of the experimental determination of unsteady periodic pressure distributions in rotating systems are reported. An indirect method is discussed, and the effects of the centrifugal force and the transmission behavior of the pressure measurement circuit were outlined. The required correction procedures are described and experimentally implemented in a test bench. Results show that the indirect method is suited to the measurement of unsteady nonharmonic pressure distributions in rotating systems.

  20. 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

    rotations, designed to reduce the reliance on import of external resources significantly. We compared a conventional system (C) and an organic system relying on manure import for soil fertility (O1) to two novel systems (O2 and O3) all based on the same crop rotation. The O2 and O3 systems represented new...... versions 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 and natural pest regulation in the crops. Reliance on resource import to the systems differed, with average annual import of nitrogen fertilizers of 149, 85, 25 and 25 kg N ha-1 in the C, O1, O2 and O3 systems, respectively. As expected, the crop yields were lower in the organic system. It...

  1. Phosphorus and potassium balance in soil under crop rotation and fertilizationBalanço de fósforo e potássio no solo sob rotação de culturas e adubações

    Directory of Open Access Journals (Sweden)

    Fabio Steiner

    2012-12-01

    Full Text Available The use of crop rotation and manure application can provide sustainability for an agricultural production system by improving soil quality and increasing nutrient use efficiency. This study aimed to evaluate the effect of mineral, organic and mineral+organic fertilization on grain yield and on soil phosphorus and potassium balance, in two crop systems under no-till, with and without rotation of cover crops. The experiment was carried out from 2006 to 2008 on a clayey Rhodic Hapludox in Marechal Cândido Rondon, Paraná State, Brazil. The cropping sequence in the rotation system involving cover crops was black oat + hairy vetch + forage turnip/corn/pigeon pea/wheat/mucuna + brachiaria + sunn hemp, and in the succession system was wheat/corn/wheat/soybean. Organic and mineral+organic fertilizations consisted of the application of solely manure and manure combined with mineral fertilizer, respectively. Soil P and K balances were calculated after the second year of the experiment, up to a depth of 0.40 m. First year corn yields were higher in the crop succession system accompanied by mineral fertilization. In the second year, wheat and soybean yield did not vary between crop systems and nutrient sources, demonstrating the residual effect of crop rotation and manure use. Crop rotation with cover crops resulted in an increase in soil K levels by promoting the recycling of this nutrient in the soil. In both crop systems, the application of mineral and organic fertilizers – either in isolation or in combination – resulted in a negative soil P and K balance in the short term. This represents a threat to the sustainability of the agricultural production system in the long term, due to the depletion of soil nutrient reserves. A utilização de rotação de culturas e a aplicação de esterco pode conferir sustentabilidade ao sistema de produção agrícola, por melhorar a qualidade do solo e aumentar a eficiência de uso de nutrientes. O objetivo deste trabalho foi avaliar o efeito da adubação mineral, orgânica e mineral+orgânica na produtividade de grãos e no balanço de fósforo e de potássio no solo em dois sistemas de culturas sob plantio direto, com e sem rotação de plantas de cobertura. O experimento foi conduzido em Marechal Cândido Rondon, Paraná, Brasil, de 2006 a 2008, em um Latossolo Vermelho. A sequência de culturas no sistema em rotação com plantas de cobertura foi aveia preta + ervilhaca + nabo/milho/guandu/trigo/mucuna + braquiária + crotalária / milho, e no sistema em sucessão foi trigo/milho/trigo/soja/milho. As adubações, orgânica e mineral+orgânica consistiram, respectivamente, da aplicação de esterco e de esterco combinado com fertilizante mineral. O balanço de P e de K no solo foi avaliado, após o segundo ano de condução do experimento, na camada de 0,0–0,40 m de profundidade. A produtividade do milho, no primeiro ano, foi superior na sucessão de culturas e na adubação mineral. No segundo ano, a produtividade de trigo e de soja não se alterou entre os sistemas de culturas e fontes de nutrientes, o que demonstra o efeito residual da rotação de culturas e do uso de esterco. Rotação de culturas com plantas de cobertura proporcionou aumento na quantidade de K no solo, por favorecer o processo de ciclagem deste nutriente do solo. Ambos os sistemas de culturas associados à aplicação fertilizante mineral e esterco de forma isolada ou combinada resultaram em saldo negativo do balanço de P e K no solo em curto prazo, representando uma ameaça para a sustentabilidade do sistema de produção em longo prazo, devido o esgotamento das reservas desses nutrientes do solo.

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

    Science.gov (United States)

    Nikishanova, T. I.

    1978-01-01

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

  3. Feature Recognition System for Rotational Features

    Directory of Open Access Journals (Sweden)

    S.S.S. Ranjit

    2013-01-01

    Full Text Available This study presents the development of a knowledge-based features recognition system for mechanical parts. The main aim of the research was to concentrate on recognition of rotational features, namely, blind hole, through hole and slanting hole to be used in automatic process planning system. The rule-based technique was applied to recognize rotational features. The recognition criteria were based upon geometrical data from Standard for Exchange of Product data file (STEP of Computer-aided Design (CAD system. The system consists of several modules, namely, pre-processing module, inference engine module and user interface module. The developed system succeeds the design activities in manufacturing industries.

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

    Directory of Open Access Journals (Sweden)

    William Deen

    2013-02-01

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

  5. Agro-climatic adaptation of cropping systems under climate change in Shanghai

    Science.gov (United States)

    Liang, Zhuoran; Gu, Tingting; Tian, Zhan; Zhong, Honglin; Liang, Yuqi

    2015-09-01

    Climate change affects the heat and water resources required by agriculture, thus shifting cropping rotation and intensity. Shanghai is located in the Taihu Lake basin, a transition zone for various cropping systems. In the basin, moderate climate changes can cause major shifts in cropping intensity and rotation. In the present study, we integrated observational climate data, one regional climate model, land use maps, and agricultural statistics to analyze the relationship between heat resources and multi-cropping potential in Shanghai. The results of agro-climatic assessment showed that climate change over the past 50 years has significantly enhanced regional agroclimatic resources, rendering a shift from double cropping to triple cropping possible. However, a downward trend is evident in the actual multi-cropping index, caused principally by the increasing costs of farming and limitations in the supply of labor. We argue that improving the utilization rate of the enhanced agro-climatic resources is possible by introducing new combinations of cultivars, adopting more laborsaving technologies, and providing incentives to farmers.

  6. Fungi Associated With Rice-Wheat Cropping System in Relation to Zero and Conventional Tillage Technologies

    Directory of Open Access Journals (Sweden)

    Shamim Iftikhar

    2003-01-01

    Full Text Available Soil mycoflora play an important role in agricultural economy of a country. Soil borne pathogen produces serious losses to the yield of a crop. In rice Bwheat cropping system due to continuous cropping and reduced rotation, soil borne pathogens have become increasingly important with the yield decline. The current study was made to have the knowledge about soil borne fungi associated with rice and wheat crop in rice- wheat cropping system under zero and conventional tillage technologies. One hundred and seven fungal species belonging to 54 genera were isolated from foliar parts, roots and soil on general and specific media. Forty three genera including 59 species were isolated for the first time from rice, wheat plants and soil of rice-wheat cropping system. The fungi were categorized into four groups (pathogenic, saprophytic, toxin producing and beneficial. Aspergillus flavus was identified as only toxin producing fungus and isolated from both rice and wheat crops. Trichoderma spp were isolated from both crops and Paecilomyces spp were isolated only from wheat fields and are known as beneficial fungi. Among the pathogenic fungi Bipolaris sorokiniana, Fusarium oxysporum and Rhizoctonia solani were isolated as pathogenic fungi both from rice and wheat soils. Alternaria trtiticina, Fusarium equiseti, F. grameniarum, F. poae, F. solani and Pythium sp. were isolated only from wheat fields whereas Nigrospora oryzae, Rhizopus oryzae and Sclerotium oryzae were isolated only form rice fields. Total fungal colony counts isolated from soil on five specific media show some effect of zero tillage on soil mycoflora.

  7. Scientific Basis for Sustainable Management of Eucalyptus and Populus as Short-Rotation Woody Crops in the U.S.

    Directory of Open Access Journals (Sweden)

    Eric D. Vance

    2014-05-01

    Full Text Available Short rotation woody crops (SRWC, fast growing tree species that are harvested on short, repeated intervals, can augment traditional fiber sources. These crops have economic and environmental benefits stemming from their capability of supplying fiber on a reduced land base in close proximity to users and when sensitive sites cannot be accessed. Eucalyptus and Populus appear to be genera with the greatest potential to provide supplemental fiber in the U.S. Optimal productivity can be achieved through practices that overcome site limitations and by choosing the most appropriate sites, species, and clones. Some Eucalyptus species are potentially invasive, yet field studies across multiple continents suggest they are slower to disperse than predicted by risk assessments. Some studies have found lower plant and animal diversity in SRWC systems compared to mature, native forests, but greater than some alterative land uses and strongly influenced by stand management, land use history, and landscape context. Eucalyptus established in place of grasslands, arable lands, and, in some cases, native forests can reduce streamflow and lower water tables due to higher interception and transpiration rates but results vary widely, are scale dependent, and are most evident in drier regions.

  8. 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 straw in B-S, the symbiotic nitrogen from the vetch crops and the green manure in B-Vm. In the conventional system, fertilization consisted on barley straw and chemical fertilizers at a rate of 80-60-30 kg N-P-K ha-1. Before the organic management, the whole plot was subjected to conventional practices. The highest total yields (and therefore the nutrients extractions) were obtained in B-Vh, followed in this order by B-B, B-S, B-F, B-Vm, B-C and b-b. The crop rotations with the highest yields favoured the microbial activity and the organic residues mineralization, although this caused, eventually, a small decrease in the soil organic matter content. Since the eighth year, this parameter remained more stable until the end of the study period. The highest decrease of soil organic matter took place in B-F and B-S, while the lowest ones happened in B-B, where the great amounts of barley straw incorporated into the soil compensated the organic matter losses. The conversion from conventional to organic management with the incorporation of the straw to the soil implies a re-adaptation process with a decrease of the soil phosphorus level by the increasing soil microbial biomass. A decrease of phosphorus during the first six years of the experiment and a posterior recovery and stabilization of this ratio by the solubilisation of the fixed phosphorus was observed. B-F and B-S presented the lowest soluble phosphorus losses, while B-C the highest ones. In the same way, the potassium level decreased during the first eight years and after that remained constant. The highest decreases took place in the rotations with the biggest amounts of barley straw; this decrease could be explained by the nutrient immobilization caused by the microbial biomass.

  9. Chapter 3.1. Dynamics of legume nitrogen fixation in intercrops and in crop rotations

    International Nuclear Information System (INIS)

    Use of nitrogen-15 lends understanding of the dynamics and interactions between various pools in agricultural systems, including nitrogen fixation by legumes and utilization of soil and fertilizer nitrogen by crops in general. Biological nitrogen fixation in sole and intercropped legumes is discussed, as are intercrop design and methods of assessing possible yield benefits from intercropping. Advantages that accrue from inclusion of legumes, only some of which are linked with nitrogen transfer, are discussed with particular reference to two case studies

  10. On weed competition and population dynamics. Considerations for crop rotations and organic farming

    OpenAIRE

    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 , Polygonum persicaria , Stellaria mediaExperiments, monitoring studies and modelling of weed population dynamics were carried out to investigate potential methods for reducing weed populations in farming systems where herbicides are not applied (organic farming). Six years o...

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

    Science.gov (United States)

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

  12. ECONOMIC AND RISK ANALYSIS OF SUSTAINABLE CROPPING SYSTEMS

    Science.gov (United States)

    This paper evaluates the profitability and economic risks associated with six cropping systems for the Sustainable Agriculture Demonstration site at the Beltsville Agricultural Research Center in Maryland. The six systems are: (1) no-tillage system, (2) corn/soybean system, (3) cover crop system, (...

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

    Science.gov (United States)

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

    2015-04-01

    Protecting natural resources while maintaining or maximizing crop yield potential is of utmost importance for sustainable crop and livestock production systems. Since soil organic matter and its decomposition by soil organisms is at the very foundation of healthy productive soils, systems research at the North Dakota State University Dickinson Research Extension Center is evaluating seasonal soil nitrogen fertility within an integrated crop and livestock production system. The 5-year diverse crop rotation is: sunflower (SF) - hard red spring wheat (HRSW) - fall seeded winter triticale-hairy vetch (THV; spring harvested for hay)/spring seeded 7-species cover crop (CC) - Corn (C) (85-90 day var.) - field pea-barley intercrop (PBY). The HRSW and SF are harvested as cash crops and the PBY, C, and CC are harvested by grazing cattle. In the system, yearling beef steers graze the PBY and C before feedlot entry and after weaning, gestating beef cows graze the CC. Since rotation establishment, four crop years have been harvested from the crop rotation. All crops have been seeded using a JD 1590 no-till drill except C and SF. Corn and SF were planted using a JD 7000 no-till planter. The HRSW, PBY, and CC were seeded at a soil depth of 3.8 cm and a row width of 19.1 cm. Seed placement for the C and SF crops was at a soil depth of 5.1 cm and the row spacing was 0.762 m. The plant population goal/ha for C, SF, and wheat was 7,689, 50,587, and 7,244 p/ha, respectively. During the 3rd cropping year, soil bulk density was measured and during the 4th cropping year, seasonal nitrogen fertility was monitored throughout the growing season from June to October. Seasonal nitrate nitrogen (NO3-N), ammonium nitrogen (NH4-N), total season mineral nitrogen (NO3-N + NH4-N), cropping system NO3-N, and bulk density were measured in 3 replicated non-fertilized field plot areas within each 10.6 ha triple replicated crop fields. Within each plot area, 6 - 20.3 cm x 0.61 m aluminum irrigation pipes were pressed into the soil as enclosures to restrict root access to soil nitrogen. Soil samples were taken as close to 2-week intervals as possible from both inside and outside the enclosures. The crop rotation N values were also compared to triple replicated perennial native grassland plot areas (predominate sp. Western wheatgrass - Pascopyrum smithii, Blue grama - Bouteloua gracilis, Little bluestem - Schizachyrium scoparium, Switchgrass - Panicum virgatum). Trends identified for both NH4-N and NO3-N indicate that the values are relatively similar with respect to seasonal change over time. There was a greater amount of soil nitrogen accumulation inside the enclosures indicating that outside the enclosures roots scavenge nitrogen for plant growth and production. Seasonally, comparing the cropping system crops, NO3-N declined mid-July and then rebounded by mid-August and continued to increase until leveling off in September. Corn NO3-N, however, did not follow this pattern, but increased from early June to the end of June and remained high until the first of September. We will present the results of bulk density data and seasonal N fertility data providing evidence for the impact of previous CC on corn production. Probable explanation for the mid-summer nitrogen decline will be presented and justification for reduced fertilizer application will be discussed.

  14. Crop productivity and economics during the transition to alternative cropping systems

    Science.gov (United States)

    Increasing economic pressures and continued environmental concerns in agricultural production have heightened the need for more sustainable cropping systems. Research is needed to identify systems that simultaneously improve the economic and social viability of farms and rural communities while prot...

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

    Science.gov (United States)

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

    2015-05-01

    Two consecutive years (4-crop) experiments were conducted to study the influence of different paddy rice-upland crop rotation in cold-waterlogged paddy field on the growth of crops and soil characteristics. The result showed that compared with the rice-winter fallow (CK) pattern, the two-year average yield of paddy rice under four rotation modes, including rape-rice (R-R), spring corn-rice (C-R), Chinese milk vetch-rice (M-R) and bean-rice (B-R), were increased by 5.3%-26.7%, with significant difference observed in C-R and R-R patterns. Except for M-R pattern, the annual average total economic benefits were improved by 79.0%-392.4% in all rotation pattern compared with the CK, and the ration of output/input was enhanced by 0.06-0.72 unit, with the most significant effect found in the C-R pattern. Likewise, compared with the CK, the contents of chlorophyll and carotenoid, and net photosynthetic rate (Pn) of rice plant were all increased during the full-tillering stage of rice in all rotation patterns. The rusty lines and rusty spots of soils were more obvious compared with the CK during the rice harvest, particularly in R-R, C-R and B-R patterns. The ratio of water-stable soil macro aggregates of plough layer of soil (> 2 mm) decreased at different levels in all rotation patterns while the ratios of middle aggregate (0.25-2 mm, expect for M-R) and micro aggregate of soil (physical and chemical properties were improved. PMID:26571667

  16. Alternative Crop Rotations in the Semi-arid Central Great Plains Region: How Much Fallow? Evaluating the Economics

    Science.gov (United States)

    The traditional crop production system in the semi-arid Central Great Plains Region (CGPR) of the U.S.A. is winter wheat (Triticum aestivum L.)-summer fallow (WF) or one crop every two years. This system is not a long-term sustainable dryland system. It is conducive to soil degradation and provide...

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

    DEFF Research Database (Denmark)

    Ferrari, Alejandro E.; Ravnskov, Sabine; Larsen, John; Tønnersen, Tina; Maronna, Ricardo A.; Wall, Luis G.

    2015-01-01

    Analysis of phospholipids (PLFA) and neutral lipids fatty acids (NLFA) was used to characterizeno-till productive agricultural soils associated with different crop rotation levels, replicated across a400 km transect in the Argentinean pampas, during two sampling seasons, summer and winter....... Highrotation (HR) management consisted in maize–wheat–soybean intense rotation including cover crops.Low rotation (LR) management trend to soybean monocultures. Soils from nearby naturalenvironments (NEs) were used as references. Fatty acids concentration in soils (nmol/g) decreased c.a.50% from summer to...... winter differentially according to soil treatment being the smallest decrease inHR management 35%. Both PLFA and NLFA profiles showed strong potential to discriminatebetween different land uses. In winter samples, some rare or unknown fatty acids were relevant forthe discrimination of agricultural...

  18. 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

    Scientific Electronic Library Online (English)

    Francisco de Jesus, Vernetti Junior; Algenor da Silva, Gomes; Luis Osmar Braga, Schuch.

    2009-09-01

    Full Text Available A avaliação quantitativa com diferentes tipos de indicadores é fundamental na determinação da sustentabilidade dos sistemas de rotação e sucessão de culturas. Este estudo teve como objetivo avaliar a sustentabilidade de algumas sucessões de culturas em solo de várzea, nos sistemas de plantio direto [...] (PD) e convencional (SC). O trabalho foi conduzido em Pelotas, Rio Grande do Sul (RS), em área experimental da Embrapa Clima Temperado. Os tratamentos foram constituídos por cinco anos de implantação de sistemas de rotação e sucessão de culturas de inverno e de primavera-verão, seguidos de dois anos de pousio e três anos da cultura do arroz irrigado. As culturas de primavera-verão foram o milho e a soja, além do arroz; enquanto que as de inverno foram gramíneas, leguminosas, consórcios, nabo forrageiro e campo natural. O delineamento experimental foi o de blocos ao acaso com parcelas subdivididas, com três repetições. As culturas de verão ocuparam as parcelas, enquanto as espécies de inverno foram alocadas nas subparcelas. Os parâmetros observados foram transformados em índices para padronizar as diversas variáveis, cada uma em relação àquela de melhor comportamento mensurado, e dispostos em quatro categorias de análise: (a) indicadores agronômicos (matéria seca e rendimento de grãos); (b) indicadores ambientais (fertilidade do solo); (c) indicadores energéticos (produção e eficiência energética); d) indicadores econômicos (valor bruto da produção e rentabilidade). Pela média harmônica obtida entre os índices dos indicadores, foram comparados os diferentes sistemas de rotação e sucessão de culturas, inferindo-se daí sua sustentabilidade e suas diferenças (Teste t P?0,05). Concluiu-se que: (a) todos os sistemas de rotação e sucessão de culturas dos quais o milho faz parte apresentam maior índice de sustentabilidade; (b) os sistemas de rotação e sucessão de culturas S1 [gramínea x soja x arroz (PD)] e S4 [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. Abstract in english 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 consiste [...] d 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 performed, and its sustaina

  19. Least limiting water range in soil under crop rotations and chiseling Intervalo hídrico ótimo em solo sob rotação de culturas e escarificação

    OpenAIRE

    Juliano Carlos Calonego,; Ciro Antonio Rosolem

    2011-01-01

    Soil water availability to plants is affected by soil compaction and other variables. The Least Limiting Water Range (LLWR) comprises soil physical variables affecting root growth and soil water availability, and can be managed by either mechanical or biological methods. There is evidence that effects of crop rotations could last longer than chiseling, so the objective of this study was to assess the effect of soil chiseling or growing cover crops under no-till (NT) on the LLWR. Crop rotation...

  20. Crop rotation effect on soil carbon and nitrogen stocks under limited irrigation

    Science.gov (United States)

    Limited irrigation management practices are being used in the Central Great Plains to conserve water by optimizing crop water use efficiency. Limited irrigation may reduce total crop biomass production and amount of crop residue returned to the soil. Crop residue production within four no-till (NT...

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

    International Nuclear Information System (INIS)

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

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

    Science.gov (United States)

    Engstrom, P.

    2013-12-01

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

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

    Science.gov (United States)

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

    2013-09-01

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

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

    International Nuclear Information System (INIS)

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

  5. Long-term effects of cropping systems on N2O emission potential

    DEFF Research Database (Denmark)

    Petersen, SØren O; Ambus, Per

    2013-01-01

    The potential for N2O emissions outside the main growing season may be influenced by long-term effects of cropping system. This was investigated by collecting intact soil cores (100 cm3, 0–4 cm depth) under winter wheat in three organic cropping systems and a conventional reference within a long-term crop rotation experiment. Average annual inputs of C in crop residues and manure ranged from 1.7 to 3.3 Mg ha?1. A simulated freeze–thaw cycle resulted in a flush of CO2 during the first 48 h, which could be mainly from microbial sources. Other samples were adjusted to approximately ?10, ?30 or ?100 hPa and amended with excess 15NO3? prior to freezing and thawing. Denitrification was the main source of N2O during a 72-h incubation at 22 °C, as judged from N2O and total 15N evolution. Although the input of C in the conventionally managed cropping system was significantly less than in the organic cropping systems, it showed higher N2O evolution at all three matric potentials. Estimates of relative gas diffusivity (DP/D0) in soil from the four cropping systems indicated that C input affected soil aeration. Soil from the two cropping systems with highest C input showed N2O evolution at DP/D0 in excess of 0.02, which is normally considered a threshold for development of anaerobic sites in the soil, presumably because the oxygen demand was also high. The study shows that cropping system affects both soil gas diffusivity and C availability, and that both characteristics significantly influence the N2O emission potential.

  6. Rotating Convection in an Anisotropic System

    CERN Document Server

    Roxin, A; Roxin, Alex; Riecke, Hermann

    2002-01-01

    We study the stability of patterns arising in rotating convection in weakly anisotropic systems using a modified Swift-Hohenberg equation. The anisotropy, either an endogenous characteristic of the system or induced by external forcing, can stabilize periodic rolls in the K\\"uppers-Lortz chaotic regime. For the particular case of rotating convection with time-modulated rotation where recently, in experiment, chiral patterns have been observed in otherwise K\\"uppers-Lortz-unstable regimes, we show how the underlying base-flow breaks the isotropy, thereby affecting the linear growth-rate of convection rolls in such a way as to stabilize spirals and targets. Throughout we compare analytical results to numerical simulations of the Swift-Hohenberg equation.

  7. GROUND BEETLE (COLEOPTERA: CARABIDAE) ASSEMBLAGES IN ORGANIC, NO-TILL, AND CHISEL-TILL CROPPING SYSTEMS OF THE MID-ATLANTIC REGION

    Science.gov (United States)

    Ground beetle assemblages were compared in organic, no-till, and chisel-till cropping systems of the USDA Farming Systems Project in Maryland. The cropping systems consisted of three-year rotations of corn (Zea mays L.), soybean (Glycine max (L.) Merr.), and wheat (Triticum aestivum L.) that were p...

  8. Nitrogen Leaching in Intensive Cropping Systems in Tam Duong District, Red River Delta of Vietnam

    OpenAIRE

    Trinh, M.V.; Keulen, H. van; Roetter, R.P.

    2010-01-01

    The environmental and economic consequences of nitrogen (N) lost in rice-based systems in Vietnam is important but has not been extensively studied. The objective of this study was to quantify the amount of N lost in major cropping systems in the Red River Delta. An experiment was conducted in the Red River Delta of Vietnam, on five different crops including rose, daisy, cabbage, chili, and a rice–rice–maize rotation during 2004 and 2005. Core soil samples were taken periodically in 20-cm inc...

  9. Effect of resource conserving techniques on crop productivity in rice-wheat cropping system

    International Nuclear Information System (INIS)

    Rice-wheat cropping system is the most important one in Pakistan. The system provides food and livelihood for more than 15 million people in the country. The productivity of the system is much lower than the potential yields of both rice and wheat crops. With the traditional methods, rice-wheat system is not a profitable one to many farmers. Hence, Cost of cultivation must be reduced and at the same time, efficiency of resources like irrigation water, fuel, and fertilizers must be improved to make the crop production system more viable and eco- friendly. Resource conserving technology (RCT) must figure highly in this equation, since they play a major role in achieving the above goals. The RCT include laser land leveling, zero-tillage, bed furrow irrigation method and crop residue management. These technologies were evaluated in irrigated areas of Punjab where rice follows wheat. The results showed that paddy yield was not affected by the new methods. Direct seeding of rice crop saved irrigation water by 13% over the conventionally planted crop. Weeds were the major problem indirect seeded crop, which could be eliminated through cultural, mechanical and chemical means. Wheat crop on beds produced the highest yield but cost of production was minimum in the zero-till wheat crop. Planting of wheat on raised beds in making headway in low- lying and poorly drained areas. Thus, resource conserving tillage technology provides a tool for making progress towards improving and sustaining wheat production system, helping with food security and poverty alleviation in Pakistan in the next few decades. (author)

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

    Directory of Open Access Journals (Sweden)

    Koala, S.

    2003-01-01

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

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

    DEFF Research Database (Denmark)

    Ferrari, Alejandro E.; Ravnskov, Sabine

    2015-01-01

    Analysis of phospholipids (PLFA) and neutral lipids fatty acids (NLFA) was used to characterizeno-till productive agricultural soils associated with different crop rotation levels, replicated across a400 km transect in the Argentinean pampas, during two sampling seasons, summer and winter. Highrotation (HR) management consisted in maize–wheat–soybean intense rotation including cover crops.Low rotation (LR) management trend to soybean monocultures. Soils from nearby naturalenvironments (NEs) were used as references. Fatty acids concentration in soils (nmol/g) decreased c.a.50% from summer to winter differentially according to soil treatment being the smallest decrease inHR management 35%. Both PLFA and NLFA profiles showed strong potential to discriminatebetween different land uses. In winter samples, some rare or unknown fatty acids were relevant forthe discrimination of agricultural practices while NLFA 20:0 appears to be a good marker of HRsoils despite season or location. The PLFA-based taxonomic biomarkers for total bacteria, Gramnegativebacteria and arbuscular mycorrhiza showed a significant trend NE>HR>LR in the wintersampling. HR management was also characterized by high levels of NLFA in winter samples as ifhigh crop rotation improves lipids reserves in soil during winter more than in monocropping soilmanagement. In conclusion, PLFA and particularly NLFA profiles appear to provide useful andcomplementary information to obtain a footprint of different soil use and managements, improvingsoil biochemistry characterization tools.

  12. Cropping System to Limit Blast Disease in Upland Rice

    OpenAIRE

    Sester, M.; Raveloson, H.; Michellon, R.; Dusserre, J.; Tharreau, D.

    2010-01-01

    Cropping system is an essential aspect to take into account to manage blast disease (caused by the fungus Magnaporthe oryzae). In addition to the selection of resistant cultivars, studies report opportunities to limit blast incidence by managing mineral amendment (N, Si, P, etc.), cultivar mixtures or other cropping system adaptations. In Madagascar, rice is the staple crop and food. Farmers traditionally grow irrigated or rainfed lowland rice wherever possible. In the mid-1980s, CIRAD and FO...

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

    Science.gov (United States)

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

    2013-04-01

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

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

    Science.gov (United States)

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

    2015-04-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-10-01

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

  16. Rotations with Coastal Bermudagrass and Fallow for Management of Meloidogyne incognita and Soilborne Fungi on Vegetable Crops

    OpenAIRE

    Johnson, A.W.; Burton, G W; Wilson, J. P.; Golden, A. M.

    1995-01-01

    The efficacy of fallow and coastal bermudagrass (Cynodon dactylon) as a rotation crop for control of root-knot nematode (Meloidogyne incognita race 1) and soilborne fungi in okra (Hibiscus esculentus cv. Emerald), squash (Cucurbita pepo cv. Dixie Hybrid), and sweet corn (Zea mays cv. Merit) was evaluated in a 3-year field trial. Numbers of M. incognita in the soil and root-gall indices were greater on okra and squash than sweet corn and declined over the years on vegetable crops following fal...

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

    DEFF Research Database (Denmark)

    Chirinda, Ngoni; Carter, Mette Sustmann

    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. The main objective of this study was to compare nitrous oxide (N2O) emissions from soil under winter wheat (Triticum aestivum L.) within three organic and one conventional cropping system that differed in type of fertilizer, presence of catch crops and proportion of N2-fixing crops. The study was replicated in two identical long-term crop rotation experiments on sandy loam soils under different climatic conditions in Denmark (Flakkebjerg—eastern Denmark and Foulum—western Denmark). The conventional rotation received 165–170 kg N ha?1 in the form of NH4NO3, while the organic rotations received 100–110 kg N ha?1 as pig slurry. For at least 11 months, as from September 2007, static chambers were used to measure N2O emissions at least twice every calendar month. Mean daily N2O emissions across the year ranged from 172 to 438 ?g N m?2 d?1 at Flakkebjerg, and from 173 to 250 ?g N m?2 d?1 at Foulum. A multiple linear regression analysis showed inter-seasonal variations in emissions (P < 0.001), but annual N2O emissions from organic and conventional systems were not significantly different despite the lower N input in organic rotations. The annual emissions ranged from 54 to 137 mg N m?2, which corresponded to 0.5–0.8% of the N applied in manure or mineral fertilizer. Selected soil attributes were monitored to support the interpretation of N2O emission patterns. A second multiple linear regression analysis with potential drivers of N2O emissions showed a negative response to soil temperature (P = 0.008) and percent water-filled pore space (WFPS) (P = 0.052) at Foulum. However, there were positive interactions of both factors with NO3-N, i.e., high N2O emissions occurred during periods when high soil nitrate levels coincided with high soil temperature (P = 0.016) or high soil water content (P = 0.056). A positive effect (P = 0.03) of soil temperature was identified at Flakkebjerg, but the number of soil samplings was limited. Effects of cropping system on N2O emissions were not observed.

  18. 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. PMID:23490323

  19. Microbial soil quality indicators under different crop rotations and tillage management / Indicadores microbianos da qualidade do solo sob diferentes rotações de culturas e manejo do solo

    Scientific Electronic Library Online (English)

    Enderson Petrônio de Brito, Ferreira; Henrique Pereira dos, Santos; Janaina Ribeiro, Costa; Helvécio, De-Polli; Norma Gouvêa, Rumjanek.

    2010-06-01

    Full Text Available Foi conduzido um experimento sob condições de campo para avaliar o efeito da forma de manejo do solo (Plantio direto - PD e plantio convencional - PC) e dos sistemas de rotação de culturas sobre o carbono da biomassa microbiana (Cmic), respiração basal do solo (RBS), quociente metabólico (qCO2), car [...] bono orgânico total (Corg) e relação carbono da biomassa microbiana: carbono orgânico total (Cmic/Corg). As amostras de solo foram coletadas em uma área cultivada com trigo como cultura de inverno e soja como cultura de verão, ambas em rotação com ervilhaca, milho e aveia preta. Amostras de solo também foram coletadas em uma floresta secundária usada com referência. Os dados de cada sistema de manejo do solo (PD e PC) foram comparados com a floresta secundária pelo teste "t" (p Abstract in english An experiment was carried out under field conditions to assess the effects of soil management (no-tillage- NT and conventional tillage- CT) and crop rotation systems on microbial biomass-C (Cmic), basal soil respiration (BSR), metabolic quotient (qCO2), soil organic carbon content (Corg) and microbi [...] al carbon to organic carbon ratio (Cmic/Corg). Soil samples were collected on an area cultivated with wheat as winter crop and soybean as summer crop, both in rotation with vetch, maize and oats. Samples were also collected in a secondary forest used as reference. Data of each management system (NT and CT) were compared to forest area by "t" test (p

  20. Bioenergy cropping systems for food, feed, fuel, and soil

    Science.gov (United States)

    Crop production can meet multiple needs including food, livestock feed, and bioenergy or biofuels. Cropping systems can be developed to focus on meeting any one of these needs, or they can be developed to simultaneously meet multiple needs. In any case, these systems must also protect the soil resou...

  1. Establishment and Growth of Self-Seeded Winter Cereal Cover Crops in a Soybean-Corn Rotation

    Science.gov (United States)

    Perpetuating cereal cover crops through self-seeding may increase adoption by reducing risk and cost. Winter rye (Secale cereale L.), wheat (Triticum aestivum L.), and triticale (x Triticosecale Wittmack) were used to develop self-seeding cover crop systems in a soybean [Glycine max (L.) Merr.]-corn...

  2. Crop Nitrogen Uptake in A Legume-wheat Rotation Using1'5N Methodology

    International Nuclear Information System (INIS)

    Afield experiment was conducted to assess the impact of residual N from legume crops, fertilizer applied N, and fallow on the subsequent wheat production. The experiment was carried out in a randomized complex block design for the years 1993 and 1994. In 1993, barley was planted as a reference crop in legume plots. Micro plots, in both years were treated with 15 N. In 1994, whole plots were planted with wheat. In 1993, the yield of lentil treatments was not significantly different. The wheat yield, responded significantly to N addition. Lentil and chickpea derived 2/3 and 3/4 of their N needs from the atmosphere, respectively. In contrast, wheat derived most of its N needs(90%) from the soil. Water consumption was similar expect for wheat fertilized at low rate of N (179.5 mm). In 1994, wheat yields, the harvesting index and water consumption were not significantly different. Traditional harvesting of lentil and fertilizing wheat at a low rate reduced significantly the N% of wheat bio-mass. The % of N derived from fertilizer (Ndff) by wheat was much higher in 1994 (4.18 to 9.24%), but it was 3.62% for the fallow treatments. The % of N derived from soil (%Ndfs) by wheat 93% in 1994 for wheat planted after legume. The results indicated that legumes depleted soil N under the croping system currently adopted in Jordan, and the benefit of fallow to the subsequent wheat crop is attributed to the increase of soil organic N mineralization. (Author) 35 refs., 3 tabs., 2 figs

  3. Password Based Rotational Multistory Car Parking System

    Directory of Open Access Journals (Sweden)

    Nayab Suhail Hamirani

    2011-12-01

    Full Text Available Parking is a big issue in thickly populated areas and in larger cities due to heavy traffic. This intended application of rotational multistory parking system effectively minimizes this issue. It results in less space and more secure parking. ATMEL microcontroller is used as main processor while LCD and motors are as complimentary components for display and rotation The model is based on circular mechanism giving low cost, less space and optimum performance. Password locking system is used to verify the object and detects number of free spaces available in the parking lot. The world has become a global market and numbers of vehicles are also increased to an uncontrollable situation. Keeping this problem the intended model is designed. Password locking system embedded in the work has made the parking of vehicles very much secure.

  4. Effect of cropping systems on adsorption of metals by soils: I. Single-metal adsorption

    Energy Technology Data Exchange (ETDEWEB)

    Basta, N.T.; Tabatabai, M.A. (Iowa State Univ., Ames (United States))

    1992-02-01

    The effect of long-term cropping systems on adsorption of metals was studied for soils obtained from two sites, Clarion-Webster Research Center (CWRC site) at Kanawha and Galva-Primghar Research Center (GPRC site) at Sutherland, under long-term rotation experiments in Iowa. Each experiment consisted of three cropping systems: continuous corn (CCCC), corn-soybean-corn-soybean (CSCS), and corn-oats-meadow-meadow (COMM), and treated with (+N) and without (0 N) ammoniacal fertilizer. In general, CSCS and COMM cropping systems did not significantly affect the metal adsorption maxima of soils obtained from both sites. Cadmium, Cu, and Pb adsorption were significantly correlated with pH and percentage base saturation for soils from both sites.

  5. Effects of Cropping Systems on No3-N Losses to Tile Drain

    Science.gov (United States)

    Kanwar, Rameshwar S.

    2006-12-01

    Diverse cropping systems can have significant impacts on nutrient losses through tile drain systems and to surface water bodies (rivers and streams). Increased transport of nitrogen to water bodies can reduce dissolved oxygen and enrich the supply of nutrients, resulting in hypoxic zones. With the objective of reducing the transport of nutrients from agricultural watersheds, long term studies (1990 to 1998) were conducted in Iowa to investigate the impact of tillage, crop rotation, and N-management practices on NO3-N leaching losses to tile drain water. Results of these studies indicated that continuous corn production systems required higher input of nitrogen fertilizers and resulted in significantly higher NO3-N leaching losses compared to rotated corn in plots either fertilized with manure or urea ammonium nitrate. Also, rotated corn gave higher corn yields, 8 megagrams per hectare (Mg/ha) versus 6 Mg/ha, than continuous corn. The higher N application rates resulted in increased NO3-N concentrations in tile water. A strip cropping system with alfalfa lowered NO3-N concentrations in tile water to less than 10 mg/l. These studies indicated that better land use practices can reduce NO3-N leaching losses to surface and ground water systems and will help in mitigating environmental concerns of the production agriculture.

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

    OpenAIRE

    Marais, A.; Hardy, M.; Booyse, M.; Botha, A.

    2012-01-01

    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 chan...

  7. The crop assessment subsystem: System implementation and approaches used for the generation of crop production reports

    Science.gov (United States)

    Mcallum, W. E.; Hatch, R. E.; Boatwright, S. M.; Liszcz, C. J.; Evans, S. M. (principal investigators)

    1979-01-01

    The primary responsibility of the crop assessment subsystem (CAS) during the three phases of LACIE was to produce crop reports that included estimates of wheat area, yield, and production, as well as a specified set of associated statistical descriptors. The operations of CAS are described with emphasis on sampling strategy, input/output data, evolution of aggregation/reporting system capabilities, and CAS aggregation procedures.

  8. Estimation of greenhouse gas emissions associated with cropping systems in southern Chile

    International Nuclear Information System (INIS)

    The use of intensive traditional cropping systems with burning crop residues and soil plough down with heavy machinery in food production is considered the cause of environmental degradation, i.e. soil erosion and atmospheric contamination with carbon and nitrogen gaseous emissions. At a world scale the soil holds 1500 Gt of carbon, which can decrease by the inadequate soil management, increasing at the same time CO2 emission. Thus, traditional soil management can produce a large soil carbon reduction, whereas conservative soil management can increase soil carbon at a rate of 1 ton ha-1 per year. Research done by the IPCC, stated that in the next 50 to 100 years, soil might be a sink for 40-80 Gt of atmospheric carbon, if soil plough is substituted by no till with crop residues management over the soil surface, the use of appropriate crop rotations with the inclusion of grain legumes and the use of animal manure. In southern Chile, 70% of cropped land area is found, along with high level of soil degradation, since the dominant use of the traditional soil management. An exercise done with data collected from a Nitrogen Use Efficiency Research Project, on an Ultisol soil, the most eroded in southern Chile, demonstrate the feasibility of increase soil carbon sequestration shifting from soil ploughing to no burn-no till system and by the inclusion of legume crop in rotations. Soil carbon input can increase from 24 to 30.5 Gg under no burn no till, from crop residues decomposition. These figures matches with real soil carbon variation content in the 0-20 cm depth, +2,2 10-6 Mg C ha-1 in no burn-no till systems in a 3 year period, and -3 10-1 Mg C ha-1 under traditional soil management. In the other hand with the continuous inclusion of grain legume crops in 188.000 has in rotation with grain annual crops, there is a potential to decrease carbon emission in 50 G, moreover, the shifting in the IX Region from traditional to conservation soil management system would mitigates carbon atmospheric emissions from 350 to 450 Gg

  9. The Influence Of Cereal Share In Crop Rotations On The Grain Yield And Quality Of Winter Wheat

    Directory of Open Access Journals (Sweden)

    Babulicová Mária

    2015-03-01

    Full Text Available The aim of our study is to find out the influence of different share of cereals and various fertilisation on the grain yield and quality of winter wheat. The long-term field trial with 40, 60 and 80% share of the cereals and two levels of fertilisation (H1 mineral fertilisation + organic manure Veget®; H2 mineral fertilisation only were carried out in the very warm and dry area of continental weather on luvi-haplic chernozem. In the years 2010–2013, the grain yield, the wet gluten content, gluten index, the falling number and sedimentation index of winter wheat according to Zeleny were investigated. The significantly higher grain yield of winter wheat was recorded after preceding crop of common pea. The yield of cereals in crop rotation with 60% share of cereals (7.00 t/ha was significantly higher than in crop rotation with 80% share of cereals (6.78 t/ha.The statistically higher wet gluten content after pea fore-crop was found out when the mineral fertilisation and organic fertiliser Veget® were applied (33.4% with comparison to the treatment with mineral fertilisation only (30.08%.

  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

    Scientific Electronic Library Online (English)

    Silvio Aymone, Genro Junior; Dalvan José, Reinert; José Miguel, Reichert; Jackson Adriano, Albuquerque.

    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 19 [...] 98 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. Abstract in english 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 to 2001: 1) success [...] ion wheat / soybean, 2) rotation corn / oat / corn+ Cajanus cajan L. Millsp / wheat / soybean / wheat, 3) rotation Cajanus cajan L. Millsp / wheat / soybean / wheat / soybean / oat, and 4) rotation Crotalaria juncea L. / wheat / soybean / oat / corn / wheat. In October of 2000 and 2001, soil samples were collected to determine physical properties. In all years, the crops yield was measured. The Oxisol cultivated under no-tillage had a high compaction degree, with soil bulk density greater and macroporosity smaller than the critical limit for clay texture. The largest limitations were observed below the layer of 0 to 0,03m, because in the uppermost layer soil mobilization by successive operations of fertilization and sowing increases soil porosity and reduces soil density. Thus, greater volume of pores is observed between soil saturation and field capacity, responsible for soil aeration, and between field capacity and wilting point, responsible for storage of plant available water. The use of cover crops once every three years was not efficient to reduce soil compaction. The yield of the subsequent crops was influenced positively in the rotation with Crotalaria juncea, while the other cropping systems did not differ from crop succession.

  11. 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 to 2001: 1 succession wheat / soybean, 2 rotation corn / oat / corn+ Cajanus cajan L. Millsp / wheat / soybean / wheat, 3 rotation Cajanus cajan L. Millsp / wheat / soybean / wheat / soybean / oat, and 4 rotation Crotalaria juncea L. / wheat / soybean / oat / corn / wheat. In October of 2000 and 2001, soil samples were collected to determine physical properties. In all years, the crops yield was measured. The Oxisol cultivated under no-tillage had a high compaction degree, with soil bulk density greater and macroporosity smaller than the critical limit for clay texture. The largest limitations were observed below the layer of 0 to 0,03m, because in the uppermost layer soil mobilization by successive operations of fertilization and sowing increases soil porosity and reduces soil density. Thus, greater volume of pores is observed between soil saturation and field capacity, responsible for soil aeration, and between field capacity and wilting point, responsible for storage of plant available water. The use of cover crops once every three years was not efficient to reduce soil compaction. The yield of the subsequent crops was influenced positively in the rotation with Crotalaria juncea, while the other cropping systems did not differ from crop succession.

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

    International Nuclear Information System (INIS)

    Short-rotation woody crops (SRWC) could potentially displace fossil fuels and thus mitigate CO2 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 106 ha), it is calculated that SRWC energy could displace 33.2 to 73.1 x 106 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 106 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 106 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

  13. Energy efficiency in long-term Mediterranean cropping systems with different management intensities

    International Nuclear Information System (INIS)

    Optimising the implementation of energy used in agriculture is an important objective in the 'Climate Action and Renewable Energy Package' adopted by the European Union. Therefore, studying the management of different cropping systems represents a good method to optimise input requirements, yield and net energy supply. The aim of this study is to compare the energy use of a 12-year rainfed cropping system, located in Tuscany, Italy. The system is cultivated under two different management intensities: a conventional system (CS) and a low input system (LIS) for a six-year crop rotation that included sugar beet, durum wheat, sorghum, sunflower, and durum wheat. In the sixth year, the soil was set-aside. The results showed that crop yield and energy yield were not significantly affected by management intensities, whereas energy efficiency of the low input system increased significantly, by about 30%. Future research should include more crops and locations to obtain further information about the range of energy parameters and their long-term trends. Furthermore, could be interesting to evaluate the overall reduction of environmental impacts and production costs that could occur limiting the use of chemicals and adopting conservative soil tillage strategies.

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

    DEFF Research Database (Denmark)

    Doltra, J; Olesen, Jørgen E; Báez, D; Louro, A; Chirinda, N

    2015-01-01

    Mitigation of greenhouse gas emissions from agriculture should be assessed across cropping systems and agroclimatic regions. In this study, we investigate the ability of the FASSET model to analyze differences in the magnitude of N2O emissions due to soil, climate and management factors in cereal......-based cropping systems. Forage maize was grown in a conventional dairy system at Mabegondo (NW Spain) and wheat and barley in organic and conventional crop rotations at Foulum (NW Denmark). These two European sites represent agricultural areas with high and low to moderate emission levels, respectively. Field...... trials included plots with and without catch crops that were fertilized with either mineral N fertilizer, cattle slurry, pig slurry or digested manure. Non-fertilized treatments were also included. Measurements of N2O fluxes during the growing cycle of all the crops at both sites were performed with the...

  15. Soil nitrous oxide and methane fluxes in integrated crop-livestock systems in subtropics

    International Nuclear Information System (INIS)

    Integrated crop-livestock (ICL) system is an agricultural practice in which crop-pasture rotation is carried out in the same field over time. In Brasil, ICL associated with no-tillage farming is increasingly gaining importance as a soil use strategy that improves food production (grain, milk and beef) and economic returns to farmers. Integrated crop-livestock-forestry (ICLF) is a recent modification of ICL in Brazil, with the inclusion of trees cultivation aiming at additional wood production and offering thermal comfort to livestock (Porfírio-da-Silva & Moraes, 2010). However, despite the increasing importance of ICL, little information is available on how this system may affect soil-atmosphere exchange of nitrous oxide (N2O) and methane (CH4)

  16. NEW TRENDS IN AGRICULTURE - CROP SYSTEMS WITHOUT SOIL

    OpenAIRE

    Ioan GRAD; Camelia M?NESCU; Mateoc, Teodor; Nicoleta MATEOC-SÎRB

    2014-01-01

    The paper studied new system of agriculture - crop systems without soil. The culture systems without soil can be called also the hydroponic systems and now in Romania are not used only sporadically. In other countries (USA, Japan, the Netherlands, France, UK, Denmark, Israel, Australia, etc..) they represent the modern crop technology, widely applied to vegetables, fruits, fodder, medicinal plants and flowers by the experts in this area. In the world, today there are millions of hectares hydr...

  17. Lentil production in Germany : testing different mixed cropping systems, sowing dates and weed controls

    OpenAIRE

    Wang, Lina

    2012-01-01

    As a kind of legume crop, lentils (Lens culinaris Medik.) with their high nutritional value are grown mainly for human consumption in many regions of the world. The crop has benefits in crop rotation due to its symbiotic N-fixation, which is important especially in organic farming, and it can also increase crop biodiversity in arable land. In Europe, lentils are considered one of the popular leguminous food crops. However, the cultivation and scientific research on lentils were neglected in G...

  18. Crop Yields and Nematode Population Densities in Triticale-Cotton and Triticale-Soybean Rotations

    OpenAIRE

    Johnson, A.W.; Dowler, C.C.; Baker, S H; Handoo, Z.A.

    1998-01-01

    Triticale cv. Beagle 82, cotton cv. McNair 235, and soybean cv. Twiggs were arranged in three cropping sequences to determine the effects of fenamiphos and cropping sequence on nematode population densities and crop yields under conservation tillage for 4 years. The cropping sequences were triticale (T)-cotton (C)-T-C, T-soybean (S)-T-S, and T-C-T-S. Numbers of Meloidogyne incognita second-stage juveniles declined on trificale but increased on cotton and soybean each year. Root-gall indices o...

  19. Perturbation theory approach to rotational tunneling systems

    Scientific Electronic Library Online (English)

    Luciano T., Peixoto.

    2000-03-01

    Full Text Available Diagrammatic perturbation theory is used to consider the problem of the coupling of a molecular group libration to the lattice vibrations in solids exhibiting rotational tunneling detected by inelastic neutron scattering. The technique is applied to a molecular group of symmetry C3 in presence of th [...] e hindering potential of the solid. The spectral density for transitions between rotational tunneling states in the ground librational level is obtained as a function of temperature. Low temperature results are presented for di erent phonon spectrum parameters. They are used to check the assumption that this coupling is the origin of the peculiar behaviour of the line shifting and broadening as a function of temperature in the INS spectra of such systems.

  20. Effects of Different Tillage and Straw Return on Soil Organic Carbon in a Rice-Wheat Rotation System

    OpenAIRE

    Zhu, Liqun; Hu, Naijuan; Yang, Minfang; Zhan, Xinhua; Zhang, Zhengwen

    2014-01-01

    Soil management practices, such as tillage method or straw return, could alter soil organic carbon (C) contents. However, the effects of tillage method or straw return on soil organic C (SOC) have showed inconsistent results in different soil/climate/cropping systems. The Yangtze River Delta of China is the main production region of rice and wheat, and rice-wheat rotation is the most important cropping system in this region. However, few studies in this region have been conducted to assess th...

  1. EUE (energy use efficiency) of cropping systems for a sustainable agriculture

    International Nuclear Information System (INIS)

    Energy efficiency of agriculture needs improvement to reduce the dependency on non-renewable energy sources. We estimated the energy flows of a wheat-maize-soybean-maize rotation of three different cropping systems: (i) low-input integrated farming (LI), (ii) integrated farming following European Regulations (IFS), and (iii) conventional farming (CONV). Balancing N fertilization with actual crop requirements and adopting minimum tillage proved the most efficient techniques to reduce energy inputs, contributing 64.7% and 11.2% respectively to the total reduction. Large differences among crops in energy efficiency (maize: 2.2 MJ kg-1 grain; wheat: 2.6 MJ kg-1 grain; soybean: 4.1 MJ kg-1 grain) suggest that crop rotation and crop management can be equally important in determining cropping system energy efficiency. Integrated farming techniques improved energy efficiency by reducing energy inputs without affecting energy outputs. Compared with CONV, energy use efficiency increased 31.4% and 32.7% in IFS and LI, respectively, while obtaining similar net energy values. Including SOM evolution in the energy analysis greatly enhanced the energy performance of IFS and, even more dramatically, LI compared to CONV. Improved energy efficiency suggests the adoption of alternative farming systems to reduce greenhouse gas emissions from agriculture. However, a thorough evaluation should include net global warming potential assessment. -- Highlights: ? We evaluated the energy flows of integrated as alternative to conventional Farming. ? Energy flows, soil organic matter evolution included, were analyzed following process analysis. ? Energy flows were compared using indicators. ? Integrated farming improved energy efficiency without affecting net energy. ? Inclusion of soil organic matter in energy analysis accrue environmental evaluation.

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

    Science.gov (United States)

    Chunxiao, Xu; Hong, Liu

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

  3. 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 depths of 0.10 and 0.20 m, in 2006 and 2007. After the first year, chiseling led to increased infiltration of water into the soil. Water infiltration was greatest in the crop rotation system with Brachiaria ruziziensis + castor bean. The activity of root systems of crops in the plots without chiseling increased the rate of water infiltration into the soil.

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

    Scientific Electronic Library Online (English)

    Maryara Buriola, Prando; Dácio, Olibone; Ana Paula Encide, Olibone; Ciro Antonio, Rosolem.

    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 infi [...] ltração 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. Abstract in english 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 Ha [...] pludult 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 depths of 0.10 and 0.20 m, in 2006 and 2007. After the first year, chiseling led to increased infiltration of water into the soil. Water infiltration was greatest in the crop rotation system with Brachiaria ruziziensis + castor bean. The activity of root systems of crops in the plots without chiseling increased the rate of water infiltration into the soil.

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

    Directory of Open Access Journals (Sweden)

    Maria Wanic

    2012-12-01

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

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

    Science.gov (United States)

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

    2016-01-01

    Global rice agriculture will be increasingly challenged by water scarcity, while at the same time changes in demand (e.g. changes in diets or increasing demand for biofuels) will feed back on agricultural practices. These factors are changing traditional cropping patterns from double-rice cropping to the introduction of upland crops in the dry season. For a comprehensive assessment of greenhouse gas (GHG) balances, we measured methane (CH4 )/nitrous oxide (N2 O) emissions and agronomic parameters over 2.5 years in double-rice cropping (R-R) and paddy rice rotations diversified with either maize (R-M) or aerobic rice (R-A) in upland cultivation. Introduction of upland crops in the dry season reduced irrigation water use and CH4 emissions by 66-81% and 95-99%, respectively. Moreover, for practices including upland crops, CH4 emissions in the subsequent wet season with paddy rice were reduced by 54-60%. Although annual N2 O emissions increased two- to threefold in the diversified systems, the strong reduction in CH4 led to a significantly lower (P < 0.05) annual GWP (CH4  + N2 O) as compared to the traditional double-rice cropping system. Measurements of soil organic carbon (SOC) contents before and 3 years after the introduction of upland crop rotations indicated a SOC loss for the R-M system, while for the other systems SOC stocks were unaffected. This trend for R-M systems needs to be followed as it has significant consequences not only for the GWP balance but also with regard to soil fertility. Economic assessment showed a similar gross profit span for R-M and R-R, while gross profits for R-A were reduced as a consequence of lower productivity. Nevertheless, regarding a future increase in water scarcity, it can be expected that mixed lowland-upland systems will expand in SE Asia as water requirements were cut by more than half in both rotation systems with upland crops. PMID:26386203

  7. Soil properties, crop production and greenhouse gas emissions in organic and conventional cropping systems

    DEFF Research Database (Denmark)

    Chirinda, Ngonidzashe; Olesen, Jørgen E; Porter, John Roy; Schjønning, Per

    2010-01-01

    : total soil organic carbon (SOC), total N, microbial biomass N (MBN), potentially mineralizable N (PMN), and levels of potential ammonium oxidation (PAO) and denitrifying enzyme activity (DEA). In situ measurements of soil heterotrophic carbon dioxide (CO2) respiration and nitrous oxide emissions were...... crops, respectively. Nevertheless, SOC levels in 2008 were similar across systems. The cumulative soil respiration for the period February to August 2008 ranged between 2 and 3 t CO2–C ha?1 and was correlated (r = 0.95) with average C inputs. In the organic cropping systems, pig slurry application and......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...

  8. 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)

  9. Increasing Cropping System Diversity Balances Productivity, Profitability and Environmental Health

    OpenAIRE

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

    2012-01-01

    Balancing productivity, profitability, and environmental health is a key challenge for agricultural sustainability. Most crop production systems in the United States are characterized by low species and management diversity, high use of fossil energy and agrichemicals, and large negative impacts on the environment. We hypothesized that cropping system diversification would promote ecosystem services that would supplement, and eventually displace, synthetic external inputs used to maintain cro...

  10. Pesticide transfer models in crop and watershed systems : a review

    OpenAIRE

    Mottes, Charles; Lesueur-Jannoyer, Magalie; Le Bail, Marianne; MALEZIAUX, Eric

    2014-01-01

    Pesticides are now occurring worldwide in almost all water resources, thus threatening the health of humans and other life. As a consequence, there is a strong social demand for designing safe cropping systems with less or no hazardous pesticides. Safe cropping systems can be designed now using pesticide transfer models. These models are mathematical tools that allow to predict the flow and concentration of pesticides in a field or a watershed. Here, we review the effects of agricultural prac...

  11. MODELIMG CROP PATTEN SYSTEM USING LINEAR PROGRAMMING

    Directory of Open Access Journals (Sweden)

    Mushtaq A. Lone

    2014-06-01

    Full Text Available In agricultural situations, farmers usually faced with the problem of how to allocate their limited production resources among cropping and livestock activities. Farmer's planners can offer effective techniques, such as linear programming (lp to address the problem and produce optimal solution. In this paper we have demonstrated that how a farmer who has limited resources such as farmers availability ,storage capacity and availability of land can be formulated as a linear programming having linear objective function with three constraints. The objective is to develop an understanding of utility of farmer's availability resources and then maximization of total profit. In our case we have selected two crops rice and corn, formulate the (lp problem and after solving through LINGO, the results showed that farmer obtained maximum profit using his resources.

  12. Trigo e Triticale em rotações de sequeiro efeitos na qualidade / Wheat and triticale in crop rotations quality effects

    Scientific Electronic Library Online (English)

    Carlos, Castro; João, Coutinho; Nuno, Moreira; António, Crespi.

    2008-12-01

    Full Text Available Este trabalho resume parte dos resultados de um ensaio de rotações que decorreu durante dez anos (1986-1996) em Vila Real (Trásos-Montes). O ensaio incluiu a rotação tradicional das condições de sequeiro da região, cereal-alqueive (TA), e rotações alternativas susceptíveis de serem adoptadas nestas [...] condições, cereal-leguminosa (TL), cereal-consociação forrageira (TC) e cereal-prado de sequeiro (TP). Os cereais das rotações foram o trigo e, posteriormente, o triticale. Determinaram-se e analisaram-se as produções de grão e palha das diversas culturas e respectivos teores em nutrientes, parâmetros do solo, peso de mil grãos, peso do hectolitro e os índices de Zeleny, Queda e Pelshenke do grão de trigo. A rotação do trigo com tremocilha (leguminosa para grão) induz no grão de trigo maiores valores do índice de Pelshenke e de teor em azoto; no triticale esta influência positiva da rotação com leguminosa fez-se sentir no peso de mil grãos e no peso do hectolitro. Como principais conclusões pode-se referir: alguma influência da rotação com tremocilha no conjunto dos parâmetros de qualida de do grão analisados, a influência decisiva do ano agrícola nos resultados e a importância da espécie de cereal para extracção de conclusões significativas. Abstract in english Results of a field trial of crop rotations conducted over a period of ten years (19861996) in Vila Real (Northeast Portugal) are presented. The rotations tested were cereal-cultivated fallow (TA), traditional in rain-fed conditions of the region, and alternative rotations that could be adopted in th [...] ese conditions: cereal-grain legume crop (TL), cereal-forage mixture (TC) and cereal-rain-fed seeded pasture (TP). The cereals were wheat and, later, triticale. Grain, straw and aerial biomass yields, nutrient levels of crops and soil parameters were evaluated together with one thousand grain weight, hectolitre weight, Zeleny, Falling Number and Pelshenke indices of cereal grain. Wheat grain from TL rotation have the highest Pelshenke indices and nitrogen content. Triticale grain from TL rotation was the heavier and with the highest specific weight. As main conclusions we can refer the influence of the rotation with lupin in the group of the parameters of grain quality , the decisive influence of the agricultural year on the results and the importance of the cereal species to obtain significant conclusions.

  13. Trigo e Triticale em rotações de sequeiro efeitos na qualidade Wheat and triticale in crop rotations quality effects

    Directory of Open Access Journals (Sweden)

    Carlos Castro

    2008-12-01

    Full Text Available Este trabalho resume parte dos resultados de um ensaio de rotações que decorreu durante dez anos (1986-1996 em Vila Real (Trásos-Montes. O ensaio incluiu a rotação tradicional das condições de sequeiro da região, cereal-alqueive (TA, e rotações alternativas susceptíveis de serem adoptadas nestas condições, cereal-leguminosa (TL, cereal-consociação forrageira (TC e cereal-prado de sequeiro (TP. Os cereais das rotações foram o trigo e, posteriormente, o triticale. Determinaram-se e analisaram-se as produções de grão e palha das diversas culturas e respectivos teores em nutrientes, parâmetros do solo, peso de mil grãos, peso do hectolitro e os índices de Zeleny, Queda e Pelshenke do grão de trigo. A rotação do trigo com tremocilha (leguminosa para grão induz no grão de trigo maiores valores do índice de Pelshenke e de teor em azoto; no triticale esta influência positiva da rotação com leguminosa fez-se sentir no peso de mil grãos e no peso do hectolitro. Como principais conclusões pode-se referir: alguma influência da rotação com tremocilha no conjunto dos parâmetros de qualida de do grão analisados, a influência decisiva do ano agrícola nos resultados e a importância da espécie de cereal para extracção de conclusões significativas.Results of a field trial of crop rotations conducted over a period of ten years (19861996 in Vila Real (Northeast Portugal are presented. The rotations tested were cereal-cultivated fallow (TA, traditional in rain-fed conditions of the region, and alternative rotations that could be adopted in these conditions: cereal-grain legume crop (TL, cereal-forage mixture (TC and cereal-rain-fed seeded pasture (TP. The cereals were wheat and, later, triticale. Grain, straw and aerial biomass yields, nutrient levels of crops and soil parameters were evaluated together with one thousand grain weight, hectolitre weight, Zeleny, Falling Number and Pelshenke indices of cereal grain. Wheat grain from TL rotation have the highest Pelshenke indices and nitrogen content. Triticale grain from TL rotation was the heavier and with the highest specific weight. As main conclusions we can refer the influence of the rotation with lupin in the group of the parameters of grain quality , the decisive influence of the agricultural year on the results and the importance of the cereal species to obtain significant conclusions.

  14. Productivity and nutrient cycling in bioenergy cropping systems

    Science.gov (United States)

    Heggenstaller, Andrew Howard

    One of the greatest obstacles confronting large-scale biomass production for energy applications is the development of cropping systems that balance the need for increased productive capacity with the maintenance of other critical ecosystem functions including nutrient cycling and retention. To address questions of productivity and nutrient dynamics in bioenergy cropping systems, we conducted two sets of field experiments during 2005-2007, investigating annual and perennial cropping systems designed to generate biomass energy feedstocks. In the first experiment we evaluated productivity and crop and soil nutrient dynamics in three prototypical bioenergy double-crop systems, and in a conventionally managed sole-crop corn system. Double-cropping systems included fall-seeded forage triticale (x Triticosecale Wittmack), succeeded by one of three summer-adapted crops: corn (Zea mays L.), sorghum-sudangrass [Sorghum bicolor (L.) Moench], or sunn hemp (Crotalaria juncea L.). Total dry matter production was greater for triticale/corn and triticale/sorghum-sudangrass compared to sole-crop corn. Functional growth analysis revealed that photosynthetic duration was more important than photosynthetic efficiency in determining biomass productivity of sole-crop corn and double-crop triticale/corn, and that greater yield in the tiritcale/corn system was the outcome of photosynthesis occurring over an extended duration. Increased growth duration in double-crop systems was also associated with reductions in potentially leachable soil nitrogen relative to sole-crop corn. However, nutrient removal in harvested biomass was also greater in the double-crop systems, indicating that over the long-term, double-cropping would mandate increased fertilizer inputs. In a second experiment we assessed the effects of N fertilization on biomass and nutrient partitioning between aboveground and belowground crop components, and on carbon storage by four perennial, warm-season grasses: big bluestem (Andropogon geradii Vitman), switchgrass (Panicum virgatum L.), indiangrass [ Sorghastrum nutans (L.) Nash], and eastern gamagrass (Tripsacum dactyloides L.). Generally, the optimum rate of fertilization for biomass yield by the grasses was 140 kg N ha-1. Nitrogen inputs also had pronounced but grass-specific effects on biomass and nutrient partitioning, and on carbon storage. For big bluestem and switchgrass, 140 kg N ha -1. maximized root biomass, favored allocation of nutrients to roots over shoots, and led to net increases in carbon storage over the study duration. In contrast, for indiangrass and eastern gamagrass, root biomass and root nutrient allocation were generally adversely affected by N fertilization and carbon storage increased only with 0 or 65 kg N ha-1. For all grasses, 220 kg N ha -1 tended to shift allocation of nutrients to shoots over roots and resulted in no net increase in carbon storage. Optimal nitrogen management strategies for perennial, warm-season grass energy crops should take into consideration the effects of N on biomass yield as well as factors such as nutrient and carbon balance that will also impact economic feasibility and environmental sustainability.

  15. Effect of tillage, rotation and crop residues on wheat crop productivity, fertilizer nitrogen and water use efficiency and soil organic carbon status in dry area (rainfed) of north-west Pakistan

    Scientific Electronic Library Online (English)

    W, Mohammad; S. M, Shah; S, Shehzadi; S. A, Shah.

    2012-12-01

    Full Text Available Crop productivity, soil organic carbon (SOC), fertilizer nitrogen and water use efficiency (WUE) in rainfed dry area is influenced by tillage, rotation and crop residues management. Field experiments were conducted during 2004-09 to study the effect of tillage, rotation and crop residues on wheat yi [...] eld, nitrogen fertilizer and water use efficiency and SOC under semi-arid condition in north-west Pakistan. The treatments consisted of three rotations: i) Wheat-fallow-wheat (farmers' practice) ii) Wheat- summer legume-wheat and iii) Wheat-summer cereal-wheat with two tillage and crop residues management treatments: i) Tillage (crop residues removed) and Tillage (crop residues retained) and ii) No-tillage (crop residues removed) and No-tillage (crop residues retained). Basal doses of N60: P60 (kg ha-1) to wheat, N90: P60 and N20: P60 (kg ha-1) to summer cereals and legumes rotation crops were applied respectively. Labeled urea having 1% 15N atom excess at 60 kg N ha-1 was applied to wheat as an aqueous solution in micro plot within each treatment plot. Changes in soil water storage were monitored with neutron moisture probe for calculation of WUE. The results revealed that the wheat grain and straw yield was not increased by the tillage treatment. Crop residues retention significantly enhanced the wheat grain and straw yield. Crop residues with no-tillage resulted in 520 kg ha-1 greater wheat grain yield than residues removed treatment. Similarly WUE, N yield and fertilizer N utilization by wheat was increased significantly by crop residues under no-tillage compared to the tillage treatment. Maximum N fertilizer utilization 24.1 %, 62.7 % and 38.0 % in wheat were obtained under no-tillage + residues treatment during 2006, 2007 and 2008 respectively. The SOC in surface soil (0-15 cm) was higher in wheat-fallow-wheat and wheat-legume-wheat rotation under no-tillage + residues treatment. The results showed that no-tillage + crop residues and legume based rotation treatment were beneficial under the rainfed (dry) conditions.

  16. Effect of tillage, rotation and crop residues on wheat crop productivity, fertilizer nitrogen and water use efficiency and soil organic carbon status in dry area (rainfed of north-west Pakistan

    Directory of Open Access Journals (Sweden)

    W Mohammad

    2012-12-01

    Full Text Available Crop productivity, soil organic carbon (SOC, fertilizer nitrogen and water use efficiency (WUE in rainfed dry area is influenced by tillage, rotation and crop residues management. Field experiments were conducted during 2004-09 to study the effect of tillage, rotation and crop residues on wheat yield, nitrogen fertilizer and water use efficiency and SOC under semi-arid condition in north-west Pakistan. The treatments consisted of three rotations: i Wheat-fallow-wheat (farmers' practice ii Wheat- summer legume-wheat and iii Wheat-summer cereal-wheat with two tillage and crop residues management treatments: i Tillage (crop residues removed and Tillage (crop residues retained and ii No-tillage (crop residues removed and No-tillage (crop residues retained. Basal doses of N60: P60 (kg ha-1 to wheat, N90: P60 and N20: P60 (kg ha-1 to summer cereals and legumes rotation crops were applied respectively. Labeled urea having 1% 15N atom excess at 60 kg N ha-1 was applied to wheat as an aqueous solution in micro plot within each treatment plot. Changes in soil water storage were monitored with neutron moisture probe for calculation of WUE. The results revealed that the wheat grain and straw yield was not increased by the tillage treatment. Crop residues retention significantly enhanced the wheat grain and straw yield. Crop residues with no-tillage resulted in 520 kg ha-1 greater wheat grain yield than residues removed treatment. Similarly WUE, N yield and fertilizer N utilization by wheat was increased significantly by crop residues under no-tillage compared to the tillage treatment. Maximum N fertilizer utilization 24.1 %, 62.7 % and 38.0 % in wheat were obtained under no-tillage + residues treatment during 2006, 2007 and 2008 respectively. The SOC in surface soil (0-15 cm was higher in wheat-fallow-wheat and wheat-legume-wheat rotation under no-tillage + residues treatment. The results showed that no-tillage + crop residues and legume based rotation treatment were beneficial under the rainfed (dry conditions.

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

    Directory of Open Access Journals (Sweden)

    Beston Bille Maonga

    2015-01-01

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

  18. Predicting the net carbon exchanges of crop rotations in Europe with an agro-ecosystem model

    OpenAIRE

    Lehuger, Simon; Gabrielle, Benoît; Cellier, Pierre; Loubet, Benjamin; Roche, Romain; Béziat, Pierre; Éric, Ceschia; Wattenbach, Martin

    2010-01-01

    Carbon fluxes between croplands and atmosphere are highly conditioned by farmer practices that involved intense atmospheric CO2 uptake during crop growing season compared to other terrestrial ecosystems. Modelling and measuring land-atmosphere carbon exchanges from arable lands are important tasks to predict the influence of vegetation dynamics on climate change and its retroactive effects on crop productivity. We tested the agro-ecosystem model CERES-EGC against gap-filled daily net CO2 exch...

  19. Counter-Rotating Tandem Motor Drilling System

    Energy Technology Data Exchange (ETDEWEB)

    Kent Perry

    2009-04-30

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

  20. The Dynamical Evolution of Rotating Stellar Systems

    Science.gov (United States)

    Arabadjis, J. S.

    1997-01-01

    The evolution of dense rotating systems is studied through the use of N-body simulations. The initial configuration for each experiment is an isotropic Kuzmin-Kutuzov model. Hernquist's tree code is utilized to simulate the dynamical evolution, with dynamical relaxation produced by the graininess of the low-N potential field. We have modified the code to simulate physicalstellar collisions, stellar evolution, mass loss and remnant formation, and star formation. Material ejected though stellar mass loss was allowed to escape some systems and was reprocessed through star formation in others. Systems whose constituent particles follow a Salpeter initial mass function rapidly undergo core collapse through Spitzer's mass segregation instability. The lump of high mass stars which condenses at the center wanders about the core in Brownian motion. All rotationally flattened systems show a decrease in flattening with time. Angular momentum transport is directed radially outward; systems containing equal mass stars transport angular momentum more efficiently than do systems following a Salpeter spectrum. In all systems the velocity dispersion in the halo evolves toward a radially biased state. In systems containing a central black hole, the dispersion becomes tangentially biased in the core, whereas it remains isotropic in systems with no black hole. Collisions occur primarily in the core; energy equipartition causes the merger remnants to sink to the system center. In systems where ejecta (due to stellar evolution processes) are allowed to escape the system, mass lossfrom the heavy core stars temporarily reduces the core density and collision rate. Collisions tend to produce a single dominant stellar merger remnant, as opposed to a swarm of intermediate-mass stars. In cases where we have suppressed all processes except relaxation and physical collisions, objects with greater flattening produce larger dominant stars. Most of the simulations performed reproduced the ratio of the central collision time scale to the central relaxation time scale found in the dwarf elliptical galaxy M32; many reproduced other features as well. The rapid central evolution of these systems due to collisions and relaxation suggests that we are either viewing M32 at a peculiar moment in its history, or that its dynamically-inferred central density is at least in part due to the present of a massive dark object, presumably a black hole.

  1. Crop-livestock systems: old wine in new bottles

    OpenAIRE

    Keulen, H. van; Schiere, J.B.

    2004-01-01

    Many farmers in tropical and temperate countries manage a mix of crops and animals. In these systems crop residues can be used to feed the animals and the excreta from the animals as nutrients for the crops. Other forms of mixing take place where grazing under fruit-trees keeps the grass short, where manure from pigs is used to 'feed' fish in a pond or where young animals bred in remote areas are fattened near urban centres with high demands for meat. In addition, inclusion of livestock alter...

  2. Crop Rotation and N Input Effects on Soil Fertility, Maize Mineral Nutrition, Yield, and Seed Composition

    Science.gov (United States)

    Yield of maize (Zea mays L.) rotated annually with soybean (Glycine max merr.) is better than its yield in monoculture. To determine how maize would respond to rotations that includes wheat (Triticum aestivum L.) and alfalfa (Medicago sativa L.) under different levels of N input, we evaluated N fer...

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

    Directory of Open Access Journals (Sweden)

    Y. Song

    2013-06-01

    Full Text Available Worldwide expansion of agriculture is impacting Earth's climate by altering the carbon, water and energy fluxes, but climate in turn is impacting crop production. To study this two-way interaction and its impact on seasonal dynamics of carbon, water and energy fluxes, we implemented dynamic crop growth processes into a land surface model, the Integrated Science Assessment Model (ISAM. In particular, we implement crop specific phenology schemes, which account for light, water, and nutrient stresses while allocating the assimilated carbon to leaf, root, stem and grain pools; dynamic vegetation structure growth, which better simulate the LAI and canopy height; dynamic root distribution processes in the soil layers, which better simulate the root response of soil water uptake and transpiration; and litter fall due to fresh and old dead leaves to better represent the water and energy interception by both stem and brown leaves of the canopy during leaf senescence. Observational data for LAI, above and below ground biomass, and carbon, water and energy fluxes were compiled from two Ameri-Flux sites, Mead, NE and Bondville, IL, to calibrate and evaluate the model performance under corn (C4-soybean (C3 rotation system over the period 2001–2004. The calibrated model was able to capture the diurnal and seasonal patterns of carbon assimilation, water and energy fluxes under the corn-soybean rotation system at these two sites. Specifically, the calculated GPP, net radiation fluxes at the top of canopy and latent heat fluxes compared well with observations. The largest bias in model results is in sensible heat flux (H for corn and soybean at both sites. With dynamic carbon allocation and root distribution processes, model simulated GPP and latent heat flux (LH were in much better agreement with observation data than for the without dynamic case. Modeled latent heat improved by 12–27% during the growing season at both sites, leading to the improvement in modeled GPP by 13–61% compared to the without dynamic case.

  4. Agregados em um Latossolo sob sistema plantio direto e rotação de culturas / Aggregates in a Rhodic Ferralsol under no-tillage and crop rotation

    Scientific Electronic Library Online (English)

    Rodrigo Arroyo, Garcia; Ciro Antonio, Rosolem.

    2010-12-01

    Full Text Available O objetivo deste trabalho foi avaliar a influência dos cultivos de outono-inverno e primavera, em sistema de plantio direto, nos agregados e matéria orgânica de um Latossolo. O experimento foi conduzido durante as safras 2006/2007, 2007/2008 e 2008/2009. No outono-inverno foram estabelecidas parcela [...] s principais com braquiária (Urochloa ruziziensis), sorgo granífero (Sorghum bicolor) e sorgo consorciado com braquiária. Na primavera, foram cultivados, em subparcelas, milheto (Pennisetum glaucum), 'Cober Crop' (Sorghum bicolor x Sorghum sudanense), crotalária (Crotalaria juncea) ou pousio. A soja foi cultivada como safra de verão, o que totalizou 12 tratamentos. A massa de matéria seca e o crescimento radicular das plantas de cobertura da primavera foram determinados em 2006 e 2008. Foram coletadas amostras de solo nas camadas de 0-5 e 5-10 cm, após o manejo das plantas de cobertura de primavera, no primeiro e terceiro anos agrícolas. Foram determinados o diâmetro médio ponderado, o diâmetro médio geométrico, o índice de estabilidade de agregados, os agregados maiores que 2 mm, a matéria orgânica e os teores de carbono orgânico total nas amostras coletadas no terceiro ano. O milheto e 'Cober Crop' produziram maior quantidade de massa de matéria seca e maior crescimento radicular. A estruturação do solo melhorou com a rotação dos cultivos das plantas de cobertura antecedentes à safra de verão. O cultivo de 'Cober Crop' e milheto influenciou a formação de macroagregados nas camadas superficiais Abstract in english The objective of this work was to evaluate the influence of fall-winter and spring crops, cultivated under no-tillage system, on the aggregates and organic matter of a Rhodic Ferralsol. The experiment was performed in the 2006/2007, 2007/2008 and 2008/2009 growing seasons. Congo signal grass (Urochl [...] oa ruziziensis), grain sorghum (Sorghum bicolor) and sorghum mixed with brachiaria were cropped in the fall-winter to consist the main plots. In the spring, millet (Pennisetum glaucum), 'Cober Crop' (Sorghum bicolor x Sorghum sudanense) and Indian hemp (Crotalaria juncea) were cultivated as subplots as well as a fallow treatment. Soybean was cropped in the summer, totaling 12 treatments. Cover crop dry matter and root growth were evaluated in 2006 and 2008. Soil samples were taken from 0-5 and 5-10 cm depths, after spring cover crops managing, in the first and third years. The mean weight diameter, geometric mean diameter, aggregate stability index, aggregates larger than 2 mm, organic matter and total organic carbon levels were evaluated in the samples of the third year. Millet and 'Cober Crop' showed higher dry matter production and root growth. The soil aggregation was improved by cover crop rotations before the summer growing season. The cultivation of 'Cober Crop' and millet influenced the macroaggregate formation in the superficial layers

  5. Estabilidade de agregados do solo após manejo com rotações de culturas e escarificação Soil aggregate stability after management with crop rotation and chiseling

    Directory of Open Access Journals (Sweden)

    Juliano Carlos Calonego

    2008-08-01

    Full Text Available O objetivo desse trabalho foi avaliar, em solo compactado, a estabilidade dos agregados influenciada pelo cultivo de espécies de cobertura em esquema de rotações de culturas, em sistema de semeadura direta, mediante o efeito da escarificação mecânica. As rotações de culturas repetidas por três anos consecutivos envolveram o cultivo de triticale e girassol, no outono-inverno, associados ao cultivo de milheto, de sorgo forrageiro e de Crotalária júncea como plantas de cobertura, antecedendo o da soja (cultura de verão. No tratamento envolvendo a escarificação mecânica, a área permaneceu em pousio entre os cultivos de outono-inverno e de verão. O experimento foi realizado na Fazenda Experimental Lageado (Botucatu-SP, nos anos agrícolas de 2003/2004, 2004/2005 e 2005/2006. O delineamento experimental foi o de blocos ao acaso, com quatro repetições, em esquema de parcelas subdivididas. As amostras para a análise da estabilidade de agregados foram coletadas nas profundidades de 0 a 0,05 m e de 0,05 a 0,10 m após o manejo das plantas de cobertura em dezembro de 2003 e de 2005. Logo no primeiro ano de instalação do experimento, o cultivo de triticale resultou em maior porcentagem de agregados com mais de 2 mm, maior DMG e maior DMP na camada de 0 a 5 cm, além de maior DMP na camada de 0,05 a 0,10 m. Já a escarificação do solo e a ausência do cultivo de plantas de cobertura proporcionaram menor porcentagem de agregados maiores que 2 mm e menor DMP na camada de 0,05 a 0,10 m. A estabilidade dos agregados foi influenciada pela rotação de culturas, sendo maior na camada de 0 a 0,05 m e de 0,05 a 0,10 m quando o triticale foi introduzido como espécie de outono-inverno.The objective of this study was to compare, in compacted soil condition, the aggregate stability after different crops rotations under no-tillage system and chiseling. The following crop rotations were repeated for three consecutive years under no-tillage: triticale (X Triticosecale Wittmack and sunflower (Helianthus annus as autumn-winter crops, together with pearl millet (Pennisetum glaucum, forage sorghum (Sorghum bicolor and sunn hemp (Crotalaria juncea in spring, preceeding soybean (summer crop. In the chiseling treatment the area was kept bare between the autumn-winter and the summer crops. The study was carried out in three growing seasons (2003/2004, 2004/2005 and 2005/2006, in Botucatu, state of São Paulo, Brazil. The experiment had a complete randomized block design with split-plot and four replications. The samples for aggregate stability analysis were collected in the layers 0-5 and 5-10 cm after cover crop desiccation, in the first and third year of the experiment. In the first year of the experiment, triticale resulted in a higher percentage of aggregates larger than 2 mm, higher Mean Geometric Diameter and Mean Weight Diameter (MWD of aggregates at the depth of 0-5 cm, and higher MWD at 5-10 cm. Chiseling and absence of cover crops reduced the percentage of aggregates larger than 2 mm and MWD values at 5-10 cm. Aggregate stability is influenced by crop rotation, and was highest in the layers 0-5 and 5-10 cm when triticale was used as autumn-winter species.

  6. Estabilidade de agregados do solo após manejo com rotações de culturas e escarificação / Soil aggregate stability after management with crop rotation and chiseling

    Scientific Electronic Library Online (English)

    Juliano Carlos, Calonego; Ciro Antonio, Rosolem.

    2008-08-01

    Full Text Available O objetivo desse trabalho foi avaliar, em solo compactado, a estabilidade dos agregados influenciada pelo cultivo de espécies de cobertura em esquema de rotações de culturas, em sistema de semeadura direta, mediante o efeito da escarificação mecânica. As rotações de culturas repetidas por três anos [...] consecutivos envolveram o cultivo de triticale e girassol, no outono-inverno, associados ao cultivo de milheto, de sorgo forrageiro e de Crotalária júncea como plantas de cobertura, antecedendo o da soja (cultura de verão). No tratamento envolvendo a escarificação mecânica, a área permaneceu em pousio entre os cultivos de outono-inverno e de verão. O experimento foi realizado na Fazenda Experimental Lageado (Botucatu-SP), nos anos agrícolas de 2003/2004, 2004/2005 e 2005/2006. O delineamento experimental foi o de blocos ao acaso, com quatro repetições, em esquema de parcelas subdivididas. As amostras para a análise da estabilidade de agregados foram coletadas nas profundidades de 0 a 0,05 m e de 0,05 a 0,10 m após o manejo das plantas de cobertura em dezembro de 2003 e de 2005. Logo no primeiro ano de instalação do experimento, o cultivo de triticale resultou em maior porcentagem de agregados com mais de 2 mm, maior DMG e maior DMP na camada de 0 a 5 cm, além de maior DMP na camada de 0,05 a 0,10 m. Já a escarificação do solo e a ausência do cultivo de plantas de cobertura proporcionaram menor porcentagem de agregados maiores que 2 mm e menor DMP na camada de 0,05 a 0,10 m. A estabilidade dos agregados foi influenciada pela rotação de culturas, sendo maior na camada de 0 a 0,05 m e de 0,05 a 0,10 m quando o triticale foi introduzido como espécie de outono-inverno. Abstract in english The objective of this study was to compare, in compacted soil condition, the aggregate stability after different crops rotations under no-tillage system and chiseling. The following crop rotations were repeated for three consecutive years under no-tillage: triticale (X Triticosecale Wittmack) and su [...] nflower (Helianthus annus) as autumn-winter crops, together with pearl millet (Pennisetum glaucum), forage sorghum (Sorghum bicolor) and sunn hemp (Crotalaria juncea) in spring, preceeding soybean (summer crop). In the chiseling treatment the area was kept bare between the autumn-winter and the summer crops. The study was carried out in three growing seasons (2003/2004, 2004/2005 and 2005/2006), in Botucatu, state of São Paulo, Brazil. The experiment had a complete randomized block design with split-plot and four replications. The samples for aggregate stability analysis were collected in the layers 0-5 and 5-10 cm after cover crop desiccation, in the first and third year of the experiment. In the first year of the experiment, triticale resulted in a higher percentage of aggregates larger than 2 mm, higher Mean Geometric Diameter and Mean Weight Diameter (MWD) of aggregates at the depth of 0-5 cm, and higher MWD at 5-10 cm. Chiseling and absence of cover crops reduced the percentage of aggregates larger than 2 mm and MWD values at 5-10 cm. Aggregate stability is influenced by crop rotation, and was highest in the layers 0-5 and 5-10 cm when triticale was used as autumn-winter species.

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

    Science.gov (United States)

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

    2015-04-01

    Soil, water, soil microbes, and solar energy are the main sources that sustain life on this planet. Without them working in concert, neither plants nor animals would survive. Considering the efficiency of animal production targets, soil must be protected and improved. Therefore, through our sustainable integrated crop and livestock research, we are studying animal and soil interactions from the soil to the plate. Integrating beef cattle systems into a diverse cropping system is providing a living laboratory for education beyond the traditional classroom setting. To establish the living learning laboratory at the Dickinson Research Extension Center, a five-crop rotation was established that included adapted cool and warm season grasses and broadleaf crops. The crop rotation is: sunflower > hard red spring wheat > fall seeded winter triticale-hairy vetch (hay)/spring seeded 7-species cover crop > Corn (85-95 day varieties) > field pea-barley intercrop. Sunflower and spring wheat are harvested for cash crop income in the rotation. Livestock integration occurs when yearling steers that had previously grazed perennial pastures until mid-August graze field pea-barley and subsequently unharvested corn. Average grazing days for field pea-barley and unharvested corn is 30 and 70 days, respectively. At the end of the grazing period, the yearling steers average 499-544 kg and are moved to a feedlot and fed an additional 75 days until slaughter. Maximizing grazing days and extending the grazing season through integration with the cropping system reduces custom feeding costs and enhances animal profit. Beef cows do not require high quality feed after their calves have been weaned. Therefore, gestating beef cows are an ideal animal to graze cover crops and crop aftermath (residue) after yearling steer grazing and farming operations have been completed. Extending the grazing season for beef cows by grazing cover crops and residues reduces winter feed cost, which is one of the highest expenses in beef cattle production. Senior research investigating the impact of livestock integration and multi-species cover crop grown within the crop rotation is studying changes in soil attributes resulting from the crop-animal integration by measuring bulk density and in-season soil fertility in the crop rotation. These responses are further contrasted with results from within the crop rotation and responses from perennial native range. Students that become engaged in the research represent a broad cross section of the consuming public and include high school junior and senior students, college undergraduate students that conduct research projects, postdoctoral research scientists engaged in senior level research, agricultural extension educators, and finally, farmer and rancher businessmen. The integrated nature of the research provides a wealth of learning opportunities for these various groups. For the high school students, visits to the living laboratory increase awareness and introduces students to a potential career path in agriculture, natural resource fields, and the many allied vocational fields that support agriculture. When college undergraduate students visit the living laboratory, they seek to address a researchable question or a problem in agriculture, while fulfilling requirements for graduation by conducting a research project. Because postdoctoral students want to be actively engaged in research and advanced learning, they are interested in conducting research in the living laboratory that can be published in peer reviewed journals. Agricultural extension educators, who advise farmers and ranchers, are looking for research results from the living laboratory that can be convey to their constituents. Farmers and ranchers participate in workshop events that give them face-to-face learning opportunities that they can use to effect change in their farm and ranch businesses. Each of these demographic groups are unique in their interest in the interaction between agricultural production and soil science. The authors will describe and discuss how each of these very different research consumers have been assisted during their experience and involvement in the living laboratory.

  8. Efeito da rotação de culturas, da monocultura e da densidade de plantas na incidência de grãos ardidos em milho / Effect of crop rotation, monoculture and plant density on the incidence of rot corn grains

    Scientific Electronic Library Online (English)

    SIMONE M., TRENTO; HELBER H., IRGANG; ERLEI M., REIS.

    2002-11-01

    Full Text Available Neste trabalho, avaliou-se o efeito de sistemas de rotação de culturas, de monocultura e de densidade de plantas na incidência de grãos ardidos em milho (Zea mays). A quantificação da incidência de grãos ardidos foi determinada pelo método de separação visual de grãos com sintomas de descoloração, c [...] ausada pela infecção por fungos na lavoura. A maior incidência de grãos ardidos ocorreu em monocultura, com média de 10,02%, enquanto sob rotação de culturas esta foi de 4,81%. A incidência de grãos ardidos foi maior à medida que a densidade de plantas aumentou para os dois sistemas. Os principais fungos isolados dos grãos de milho nos sistemas de rotação e monocultura foram Cephalosporium spp., Diplodia spp., Fusarium graminearum, F. moniliforme e F. subglutinans. Abstract in english The effect of crop rotation, monoculture, and plant density on the incidence of injuried corn (Zea mays) grains was evaluated in this work. Visual separation of grains showing symptoms of discoloration caused by fungi in the field was used to quantify the incidence. The highest incidence of injuried [...] grains, an average of 10.02% was found in continuous cropping system, while in the crop rotation system the incidence average was 4.81%.The incidence of injuried grains was highest in both systems as plant density increased. The main fungi isolated from corn grains in crop rotation and monoculture were Cephalosporium spp., Diplodia spp., Fusarium graminearum, F. moniliforme and F. subglutinans.

  9. Effects of different cropping systems and weed management methods on free energy and content of pigments in maize

    Directory of Open Access Journals (Sweden)

    Igor Spasojević

    2014-03-01

    Full Text Available Rotation is a cropping system that has many advantages and ensures better crop growth and yielding. Its combinination with other cropping measures can ensure optimal crop density for maximal growth and photosynthesis efficiency. The aim of this study was to investigate the influence of different cropping systems: monoculture and two rotations, including maize, wheat and soybean (MSW and MWS, and different weed management methods (weed removal by hoeing, application of a full recommended herbicide dose (RD and half that dose (0.5 RD, and weedy check on weed biomass and maize growth parameters - leaf area index (LAI, free energy, contents of chlorophyll and carotenoids, grain yield, and their possible relationships in two fields of the maize hybrids ZP 677 (H1 and ZP 606 (H2. The lowest LAI and grain yield were found in monoculture, particularly in weedy check, which had relatively high weed infestation. Higher weed biomass was also observed in herbicide treated plots in monoculture. Such high competition pressure indicates a stress reflected on reduced LAI and chlorophyll content, and increased free energy and content of carotenoids. On the other hand, rotation, particularly if it is combined with the application of herbicides or hoeing, had a positive impact on yielding potential by increasing LAI and the contents of chlorophyll and carotenoids, and decreasing free energy.

  10. Fate of nitrogen from mineral fertilizer and liquid manure over a two-year crop rotation

    International Nuclear Information System (INIS)

    Nitrogen-15-labelled fertilizer was used to gain a better understanding of fertilizer-N uptake by crops in the year of application, the immobilization of applied N in the soil, fertilizer N uptake by a subsequent crop, and fertilizer-N leaching to groundwater. Fertilizer-N-utilization values for winter wheat (planted in the first year) were 15 to 36%, and 27 to 63% of the applied N was immobilized in the soil. Losses of fertilizer N by leaching to groundwater were not significant. At harvest of the winter wheat, between 50% and 82% of applied fertilizer N was accounted for in total. Unaccounted-for N was probably lost by volatilization. Only a few kilograms of applied N were taken up by the succeeding cover crop and corn. (author)

  11. Consequences for weed management in crop rotations by introducing imidazolinone-tolerant oilseed rape varieties

    OpenAIRE

    Krato, Christoph

    2012-01-01

    OSR (Brassica napus L.) is one of the most important arable oil crops globally and is grown on an area of 31,680,945 ha as winter- and spring-sown varieties. The harvest is mainly used in human nutrition, animal feeding and as a renewable resource for the production of paints, varnishes and biodiesel. OSR can be considered a quite competitive crop but nonetheless weed control is carried out on the vast majority of the grown area. The most common treatments are done PRE-E or early POST-E, m...

  12. Performance testing rotating gamma camera SPECT systems

    International Nuclear Information System (INIS)

    A reasonably simple protocol for testing the performance of rotating gamma camera SPECT systems has been established, which could be performed in about 10 hours. This protocol has been used to test almost all currently available systems, including GE, Siemens, Technicare, Elscint, Phillips, CGR, etc. In general, several models of a given system were tested in order to give an indication of the range of results that might be obtained. Reconstructions were performed in a standard manner (Uniformity correction, Ramp filter, no attenuation correction) in order to try to eliminate the effect of differences in software. In addition to using the Jaszczak phantom as an overall test pattern, measurements were made of spatial resolution, energy resolution, contrast, variations of sensitivity and uniformity with angle, etc. Results indicated that some systems, with a high resolution collimator and after very careful setting up, could achieve a spatial resolution of the order of 11mm, with good image quality. Not all commercially available systems performed as well. Strong indication was given of the need to improve spatial resolution, even at the expense of sensitivity, confirming the results from simulated tomographic data for various design compromises. Tests were also performed varying the energy window used. It was found that only very few system were capable of producing artefact free images with other than a symmetric photopeak window. However, very significant improvement of image quality of current systems with respect to older systems were noted. This protocol has been used, in addition, to establish a routine quality assurance program for such SPECT systems

  13. Development and application of a heuristic for flexible decisions about herbicide use in crop rotation field experiments

    Directory of Open Access Journals (Sweden)

    Kunze, Thomas

    2014-02-01

    Full Text Available Weeds in agriculture are controlled indirectly by strategic management tools (crop rotation, fertilization, tillage. Herbicide use is a direct tactical management tool for weed control. However, strategic and tactical measures interact together regarding weed management and thereby influence weed infestations and herbicide use. This study investigated the impact of strategic and tactical decisions in combination. It describes the development of a heuristic, which can be applied for different weed situations. By considering weed densities and species specific loss factors flexible herbicide decisions are derived for specific weed infestations and a given herbicide intensity. The implementation of decisions based on the heuristic is shown as an example for winter wheat crops in a rotation experiment at the study sites Rostock and Göttingen (Germany. The intensity of herbicide use serves for contrasts with three degrees (high, medium and low representing three levels of target efficacy (100%, 85% and 60%. The introduced heuristic enables reproducible decisions for various weed infestations. First results show reduced herbicide use from high to the low level of herbicide intensity in terms of reduced numbers of active ingredients use.

  14. Productivity of winter rye in organic vs. Conventional cropping system

    Directory of Open Access Journals (Sweden)

    Olja?a Jasmina M.

    2010-01-01

    Full Text Available Rye is a cereal which is very much demanded at the market, for making a special kind of bread, but it is little grown in Serbia. The aim of this paper is to investigate possibilities of organic growing of winter rye, comparing with the conventional one, in agroecological conditions of Valjevo hilly region during 2008/2009 and 2009/2010 cropping seasons. The trial was set up in a village of Kotešica, on soil which had not been used for agriculture for 7 years. In organic cropping system three combinations of microbiological fertiliser baktofil with zeolite and hydrogel were used prior to sowing. Half of each plot was treated with foliar microbiological fertiliser Slavol during crop growing period. In conventional cropping system three variants with mineral fertilisers were included: NPK, NPK+zeolite, NPK+hydrogel. Results of the yield obtained in the experiment showed a significant difference between two seasons, 2008/2009 and 2009/2010. In comparison with the control, the treatments in an organic cropping system resulted with statistically insignificant differences for mean values in both years, while the mean in conventional cropping system has significantly higher yield of winter rye. Organic cropping system under conditions of Valjevo hilly region did not give significantly lower rye yield compared with the conventional one in a moderate growing season such was 2008/2009. The combination of soil microbiological fertiliser (Baktofil with foliar fertiliser (Slavol and zeolite gave the highest winter rye grain yield in all other treatments in the second year of investigation. In a very wet season (2009/2010 mineral fertiliser NPK showed an advantage, especially in combinations with zeolite, and this treatment can be recommended.

  15. Influence of defects on the vibrations of rotating systems

    International Nuclear Information System (INIS)

    For high rotation speeds, the imperfections (cracks, anisotropy...) of rotating machinery of the energy sector lead to a specific vibratory behavior which can damage the machine. The simulation of rotating machinery are usually realized for systems without defect. The aim of this thesis is to understand the influence of defects and to propose an algorithm to predict the dynamical behavior. In a first part the author studies the simplified rotating oscillators to propose a numerical method in order to taking into account the dynamic of these systems. This method is then applied to real rotating machinery with the Cast3m software. The numerical results are validated with experiments. (A.L.B.)

  16. Soil water retention and s index after crop rotation and chiseling / Retenção de água no solo e índice s influenciados por rotação de culturas e escarificação

    Scientific Electronic Library Online (English)

    Juliano Carlos, Calonego; Ciro Antonio, Rosolem.

    2011-12-01

    Full Text Available A compactação do solo pode ser corrigida mecanicamente ou usando espécies vegetais com sistema radicular vigoroso. Um experimento foi conduzido com soja (Glycine max) em rotação com triticale (X Triticosecale) e girassol (Helianthus annuus) cultivados no outono/inverno, associados com milheto (Penni [...] setum glaucum), sorgo (Sorghum bicolor) ou crotalária (Crotalaria juncea) cultivados na primavera. Rotações sob semeadura direta foram comparadas com um tratamento com escarificação no início do experimento. A qualidade do solo foi estimada usando-se o índice S e as curvas de retenção de água do solo nas profundidades de 0-0,05, 0,075-0,15, 0,15-0,20, 0,275-0,325 e 0,475-0,525 m. As rotações de culturas e a escarificação melhoraram a qualidade do solo, aumentando o índice S acima de 0,035 até 0,20 m no perfil do solo. Entretanto, a melhoria na qualidade do solo, conforme determinada por meio do índice S, não justifica o uso de escarificação mecânica, uma vez que as parcelas sob rotação de culturas em semeadura direta mostraram qualidade física do solo semelhante após três anos. Abstract in english Soil compaction can be minimized either mechanically or biologically, using plant species with vigorous root systems. An experiment was carried out with soybean (Glycine max) in rotation with triticale (X Triticosecale) and sunflower (Helianthus annuus) in fall-winter associated with pearl millet (P [...] ennisetum glaucum), grain sorghum (Sorghum bicolor) or sunn hemp (Crotalaria juncea) in spring. Crop rotation under no-till was compared with mechanical chiseling. The experiment was carried out in Botucatu, São Paulo State, Brazil. Soil quality was estimated using the S index and soil water retention curves (in the layers of 0-0.05, 0.075-0.125, 0.15-0.20, 0.275-0.325, and 0.475-0.525 m deep). Crop rotation and chiseling improved soil quality, increasing the S index to over 0.035 to a depth of 20 cm in the soil profile. The improved soil quality, as shown by the S index, makes the use of mechanical chiseling unnecessary, since after 3 years the soil physical quality under no-tilled crop rotation and chiseling was similar.

  17. Use of the crown competition factor concept to select clones and spacings for short-rotation woody crops.

    Science.gov (United States)

    Hall, R. B.

    1994-01-01

    Plantation spacing and rotation age are interrelated critical factors in optimizing production of short-rotation woody crops (SRWC). Different genotypes have different spacing and rotation-age optima. I have developed a method for estimating the optimum for new Populus clones based on a modification of the crown competition factor (CCF) concept, which was originally developed for conventional forestry practices with older trees. Measurements of as few as 100 trees of a new clone over a relatively short time period could be used to predict the optimum spacing and rotation age combinations for that clone. The technique could also be used to quantify basic differences in crown architecture and yield physiology among genotypes. One set of at least 20 trees is planted at an open-grown spacing and measured annually for crown and basal stem diameters. The regression of crown diameter on stem diameter is used to calculate the land area that would be occupied per open-grown tree at various stem diameters. This allows prediction of the spacing needed to reach the minimum density for maximum stand growth at a given age or stem size. A second set of 80 measurement trees is planted in a closely spaced set of Nelder arcs to force overstocking within the first few years of growth. Productivity measurements on these trees establish the upper limit on CCF for maximum stand growth. The data are then used to calculate the best spacing and rotation age combination for a new clone. Application of this model may lead to a better understanding of the productive advantages of the sylleptic branch habit, different branch angles and seasonal growth rates, different carbon allocation strategies, and responses to competition. PMID:14967657

  18. SELF BALANCING SYSTEM FOR ROTATING MECHANISMS

    Directory of Open Access Journals (Sweden)

    Marco Antonio Meraz

    2005-08-01

    Full Text Available A self balancing system analysis is presented which utilizes freely moving balancing bodies (balls rotating in unison with a rotor to be balanced. Using Lagrange´s Equation, we derive the non-linear equations of motion for an autonomous system with respect to the polar coordinate system. From the equations of motion for the autonomous system, the equilibrium positions and the linear variational equations are obtained by the perturbation method. Because of resistance to motion, eccentricity of race over which the balancing bodies are moving and the influence of external vibrations, it is impossible to attain a complete balance. Based on the variational equations, the dynamic stability of the system in the neighborhood of the equilibrium positions is investigated. The results of the stability analysis provide the design requirements for the self balancing system.Se presenta el análisis de un sistema de autobalance el cual utiliza bolas libres de movimiento rotando con el rotor que será balanceado. Se usa la ecuación de Lagrange para derivar un sistema de ecuaciones no lineales para un sistema autónomo con respecto a un sistema de coordenadas polares. De las ecuaciones de movimiento, se obtienen ecuaciones linealizadas variacionalmente y posiciones de equilibrio por el método de perturbación. A causa de la resistencia al movimiento, la excentricidad y el movimiento de los cuerpos libres que son provocados por la influencia de vibraciones externas, hace imposible obtener un balanceo completo. Basado en el método variacional, se investiga el comportamiento dinámico del sistema en la frontera de la posición de equilibrio. Los resultados del análisis de estabilidad proveen los requerimientos de diseño para el sistema de autobalance.

  19. Grass-clover undersowing affects nitrogen dynamics in a grain legume–cereal arable cropping system

    DEFF Research Database (Denmark)

    Hauggaard-Nielsen, Henrik; Mundus, Simon; Jensen, Erik Steen

    2012-01-01

    (Lolium perenne L.) – white clover (Trifolium repens L.) catch crop followed by a first crop of spring wheat (Triticum aestivum L.) and second crop of winter triticale (Triticale hexaploide L.). The rotation sequence was repeated twice. Natural 15N abundance techniques were used to determine grain legume...... N2 fixation and 15N labeling technique to determine the fate of pea and oat residue N recovery in the subsequent crop. The subsequent spring wheat and winter triticale crop yields were not significantly affected by the previous main crop, but a significant effect of catch crop undersowing was...... observed. A higher soil mineral N content in the soil profile without undersown grass-clover increased the spring wheat yield. This effect was circumvented in the subsequent winter triticale, where yields in the treatments with catch crops undersown were significantly greater. The grass-clover catch crop...

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

    Science.gov (United States)

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

    2015-01-01

    Although short-rotation woody crop biomass production technology has demonstrated a promising potential to supply feedstocks for bioenergy production, the water and nutrient processes in the woody crop planation ecosystem are poorly understood. In this study, a computer model was developed to estimate the dynamics of water and nitrogen (N) species (e.g., NH-N, NO-N, particulate organic N, and soluble organic N [SON]) in a woody crop plantation using STELLA (tructural hinking and xperiential earning aboratory with nimation) software. A scenario was performed to estimate diurnal and monthly water and N variations of a 1-ha mature cottonwood plantation over a 1-yr simulation period. A typical monthly variation pattern was found for soil water evaporation, leaf water transpiration, and root water uptake, with an increase from winter to summer and a decrease from summer to the following winter. Simulations further revealed that the rate of soil water evaporation was one order of magnitude lower than that of leaf water transpiration. In most cases, the relative monthly water loss rates could be expressed as evapotranspiration > root uptake > percolation > runoff. Leaching of NO-N and SON depended not only on soil N content but also on rainfall rate and duration. Leaching of NO-N from the cottonwood plantation was about two times higher than that of SON. The relative monthly rate of N leaching was NO-N > SON > NH-N. This study suggests that the STELLA model developed is a useful tool for estimating water and N dynamics from a woody crop plantation. PMID:25602335

  1. Produção de gado de corte e acúmulo de matéria seca em sistema de integração lavoura-pecuária em presença e ausência de trevo branco e nitrogênio Beef cattle production and dry matter accumulation in the crop-pasture rotation system in presence and absence of white clover and nitrogen

    Directory of Open Access Journals (Sweden)

    Alceu Luiz Assmann

    2004-02-01

    Full Text Available O trabalho foi conduzido com o objetivo de verificar a influência da adubação nitrogenada em uma pastagem de azevém (Lolium multiflorium L. e aveia (Avena strigosa Scherb em presença e ausência de trevo branco (Trifolium repens L., conferida pelo acúmulo e produção de matéria seca, ganho médio diário, ganho de peso vivo e carga animal no sistema de integração lavoura-pecuária sob sistema de plantio direto. A cultura antecessora da pastagem foi a soja (Glycine Max L.. O delineamento experimental foi em blocos completos ao acaso, com parcelas subdivididas e três repetições. Nas parcelas, foram testadas quatro doses de nitrogênio (0, 100, 200 e 300 kg.ha-1 e nas subparcelas, a combinação de presença e ausência de trevo branco. A elevação das doses crescentes de N aumentaram de forma linear crescente o acúmulo e a produção de matéria seca da pastagem. A carga animal e o ganho de peso vivo por hectare de bovinos aumentaram com o incremento de nitrogênio. Os resultados demonstram o efeito da adubação nitrogenada no acúmulo diário, na produção de matéria seca, carga animal e no ganho de peso vivo.The research was carried out to verify the influence of the nitrogen input in an Italian ryegrass (Lolium multiflorium L. and oat (Avena strigosa Scherb pasture, in presence and absence of white clover (Trifolium repens L., checked by the dry matter accumulation, dry matter yield, average daily gain, liveweight gain and stocking rate a crop-pasture rotation system, on no tillage system. Soybean (Glycine Max L. was cultivated before the grass. The experimental design was complete randomized blocks with split-plot model and three replications. In the plots, four nitrogen levels were tested (0, 100, 200 and 300 kg.ha-1 and in the split-plot model, the presence and absence of white clover. Increasing nitrogen levels increased in a cresecent linear way the dry matter accumulation and dry matter yield. The stocking rate and liveweight gain per hectare of bovine increased, as the nitrogen levels increased. The results showed the effect of nitrogen input on the daily accumulation rate, dry matter yield, stocking rate and liveweight gain.

  2. Soil surface carbon dioxide efflux of bioenergy cropping systems

    Science.gov (United States)

    Bioenergy cropping systems have been proposed as a way to enhance United States energy security. However, research on greenhouse gas emissions from such systems is needed to ensure environmental sustainability in the field. Since soil aeration properties are dynamic, high-resolution data are needed ...

  3. Diagnostic system based on vibration measurement for rotating machines

    International Nuclear Information System (INIS)

    Large-scale electric power plants have a number of rotating machines which occupy important positions in the plant system. Therefore, respective users assign several countermeasures to improve their reliability and availability. Especially, the maintenance of rotating machines for efficient operation as well as the promotion and strengthening of precautions for safety have now become system requirements. In the above context, we have developed a machinery diagnostic system for rotating machinery, fully utilizing the experience and technology that we have so for developed. This paper introduces the various diagnostic systems for rotating machines. (author)

  4. Long-term effects of cropping system on N2O emission potential

    DEFF Research Database (Denmark)

    Petersen, SØren O.; Ambus, Per

    2013-01-01

    The potential for N2O emissions outside the main growing season may be influenced by long-term effects of cropping system. This was investigated by collecting intact soil cores (100 cm3, 0-4 cm depth) under winter wheat in three organic cropping systems and a conventional reference within a long-term crop rotation experiment. Average annual inputs of C in crop residues and manure ranged from 1.7 to 3.3 Mg ha-1. A simulated freeze-thaw cycle resulted in a flush of CO2 during the first 48 h, which could be mainly from microbial sources. Other samples were adjusted to approximately –10, -30 or –100 hPa and amended with excess 15NO3- prior to freezing and thawing. Denitrification was the main source of N2O during a 72-h incubation at 22 °C, as judged from N2O and total 15N evolution. Although the input of C in the conventionally managed cropping system was significantly less than in the organic cropping systems, it showed higher N2O evolution at all three matric potentials. Estimates of relative gas diffusivity (DP/D0) in soil from the four cropping systems indicated that C input affected soil aeration. Soil from the two cropping systems with highest C input showed N2O evolution at DP/D0 in excess of 0.02, which is normally considered a threshold for development of anaerobic sites in the soil, presumably because the oxygen demand was also high. The study shows that cropping system affects both soil gas diffusivity and C availability, and that both characteristics significantly influence the N2O emission potential.

  5. Control of the Soybean Cyst Nematode by Crop Rotation in Combination with a Nematicide

    OpenAIRE

    Sasser, J. N.; Uzzell, Grover

    1991-01-01

    An experiment to evaluate the control of soybean cyst nematodes compared 1-year, 2-year, and 3-year nonhost rotations with continuous soybeans (Glycine max) in 0.2-ha plots. In a second 1-year rotation, the plots were planted to soybean or corn (Zea mays) after fumigation in the spring with a split application of 1,3-dichloropropene (748.2 liters/ha). The effects of the nematicide were apparent the first year. Soybean yield was 1,482 kg/ha compared to 233 kg/ha in the untreated plots. In the ...

  6. Cultivation of energy crops with low-input factors short rotation forestry

    International Nuclear Information System (INIS)

    This paper concentrates on the cultivation of wood solely for energy purposes in the form of Short Rotation Forestry including the possibility of cultivating with the use of less fertiliser, irrigation and pesticides. Short rotation forestry is a type of forest cultivation which depends on the fast juvenile growth of a few broad-leaved tree species and their ability to cut reproduction and formation of stump shoots. Through intensive cultivation, these characteristics are exploited with the aim of producing biomass which is used for production of energy. (author)

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

    International Nuclear Information System (INIS)

    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

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

    Science.gov (United States)

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

    2015-09-01

    Sloping croplands could result in soil erosion, which leads to non-point source pollution of the aquatic system in the Three Gorges Reservoir Region. Mulberry, a commonly grown cash plant in the region, is traditionally planted in contour hedgerows as an effective management practice to control soil erosion and non-point source pollution. In this field study, surface runoff and soil N and P loss on sloping land under crop-mulberry management were investigated. The experiments consisted of six crop-mulberry treatments: Control (no mulberry hedgerow with mustard-corn rotation); T1 (two-row contour mulberry with mustard-corn rotation); T2 (three-row contour mulberry with mustard-corn rotation); T3 (border mulberry and one-row contour mulberry with mustard-corn rotation); T4 (border mulberry with mustard-corn rotation); T5 (two-row longitudinal mulberry with mustard). The results indicated that crop-mulberry systems could effectively reduce surface runoff and soil and nutrient loss from arable slope land. Surface runoff from T1 (342.13 m(3) hm(-2)), T2 (260.6 m(3) hm(-2)), T3 (113.13 m(3) hm(-2)), T4 (114 m(3) hm(-2)), and T5 (129 m(3) hm(-2)) was reduced by 15.4, 35.6, 72.0, 71.8, and 68.1%, respectively, while soil loss from T1 (0.21 t hm(-2)), T2 (0.13 t hm(-2)), T3 (0.08 t hm(-2)), T4 (0.11 t hm(-2)), and T5 (0.12 t hm(-2)) was reduced by 52.3, 70.5, 81.8, 75.0, and 72.7%, respectively, as compared with the control. Crop-mulberry ecosystem would also elevate soil N by 22.3% and soil P by 57.4%, and soil nutrient status was contour-line dependent. PMID:25957753

  9. Changes in grass-weed seedbanks in relation to crops and rotations

    OpenAIRE

    A.F. Belo; Dias, L.S.

    1998-01-01

    Forage, chikpea, medics, wheat, oilseed rape, and sunflower were cultivated during four years as part of ten different types of rotation which always included wheat. Grass-weed seedbanks were evaluated annually before seeding. The single most important reason for the control of grass-weed seedbanks or its failure seems to be the effectiveness of above-groud grass-weed control.

  10. 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 results underlined the negative effects of permanent crops, such as vineyards, olive groves, and orchards, in particular during the winter season. This research highlights the importance of farmland areas mainly for wintering species and the importance of open areas for breeding species in the Mediterranean Basin. This may be true even when the species’ spatial distribution could be affected by biogeography. An important result showed that the hotspots for breeding species cannot be used as a surrogate for the wintering species, which were often not considered in the planning of protected areas. PMID:26918960

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

    Directory of Open Access Journals (Sweden)

    E. A. Makinde

    2008-01-01

    Full Text Available Problem statement: In assessing fertilizer effects to sustain an intensive cropping system, the residual effects of fertilizer applied to preceding maize on the growth and yield of cassava and the effects of intercropping with soybean were studied in field experiments at Ibadan, Nigeria. Approach: Maize, established in April was fertilized using either organic manure or inorganic fertilizer or a mixture of organic manure and inorganic fertilizers. Organic manure was an equal mixture of domestic waste collected from a composted refuse dumping site applied at l0 t ha-1. Inorganic fertilizer was 150kg N supplied as urea and 50 kg P ha-1 as Single Super phosphate fertilizer. The mixture of organic and inorganic fertilizer treatment was 5 tonnes organic manure and 75kg N+25 kg P ha-1. Cassava was established in June and soybean planted in July, after harvesting maize. Results: Organic fertilizer treatment gave the tallest plants of 53 cm. Plants from sole inorganic fertilizer and from a mixture of organic and inorganic fertilizers had comparable heights but were significantly lower than plants from sole organic fertilizer application. Organic fertilizer application gave the highest seed yield of 481 kg ha-1 that was significantly higher than 380 kg ha-1 observed from a mixture of organic and inorganic fertilizers. Stover yield followed the same trend as seed yield. Cassava plant height was increased with fertilization but was reduced with intercropping. Sole organic fertilization had the tallest plants. Plant leaf area was neither significantly affected by fertilizer type nor cropping system. Fresh root yield was significantly reduced by 16% with soybean intercropping. Sole organic fertilizer application gave the highest yields of 22 tons ha-1 in sole crop and 18 tons ha-1 in intercrop with soybean. Conclusion: Cultivating an early season maize crop, followed by a cassava-soybean intercrop is more favored with application of 10 tons ha-1 organic fertilizer.

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

    Science.gov (United States)

    Polonskiy, Vadim; Polonskaya, Janna

    The perspective crops for the bioregenerative human life support systems V.I. Polonskiy, J.E. Polonskaya aKrasnoyarsk State Agrarian University, 660049, Krasnoyarsk, Russia In the nearest future the space missions will be too long. In this case it is necessary to provide the crew by vitamins, antioxidants, and water-soluble dietary fibers. These compounds will be produced by higher plants. There was not enough attention at present to increasing content of micronutrients in edible parts of crops candidates for CELSS. We suggested to add the new crops to this list. 1. Barley -is the best crop for including to food crops (wheat, rice, soybean). Many of the health effects of barley are connected to dietary fibers beta-glucan of barley grains. Bar-ley is the only seed from cereals including wheat with content of all eight tocopherols (vitamin E, important antioxidant). Barley grains contain much greater amounts of phenolic compounds (potential antioxidant activities) than other cereal grains. Considerable focus is on supplement-ing wheat-based breads with barley to introduce the inherent nutritional advantages of barley flour, currently only 20We have selected and tested during 5 generations two high productive barley lines -1-K-O and 25-K-O. Our investigations (special breeding program for improving grain quality of barley) are in progress. 2. Volatile crops. Young leaves and shoots of these crops are edible and have a piquant taste. A lot of organic volatile compounds, oils, vitamins, antioxidants are in their biomass. These micronutrients are useful for good appetite and health of the crew. We have investigated 11 species: basil (Ocimum basilicum), hyssop (Hyssopus officinalis), marjoram (Origanum majorana), sweet-Mary (Melissa officinalis), common thyme (Thymus vulgaris), creeping thyme (Thymus serpyllum), summer savory (Satureja hortensis), catnip (Nepeta cataria), rue (Ruta graveolens), coriander (Coriandrum Ativum), sulfurwort (Levisticum officinale). These plants were grown under artificial light conditions from 5 to 7 months. All crops were cut periodically in every month. On the base of our investigations it is possible to recommend for using in CELSS the next crops: marjoram, sweet-Mary and common thyme. The micronutrients containing in barley and above mentioned volatile crops will be useful for good appetite and health of the crew.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1985-08-01

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

  14. Rotating Machinery Predictive Maintenance Through Expert System

    OpenAIRE

    M. Sarath Kumar; B. S. Prabhu

    2000-01-01

    Modern rotating machines such as turbomachines, either produce or absorb huge amount of power. Some of the common applications are: steam turbine-generator and gas turbine-compressor-generator trains produce power and machines, such as pumps, centrifugal compressors, motors, generators, machine tool spindles, etc., are being used in industrial applications. Condition-based maintenance of rotating machinery is a common practice where the machine's condition is monitored constantly, so that tim...

  15. Soilless cultivation system for functional food crops

    International Nuclear Information System (INIS)

    This soilless cultivation system is based on the fertigation system and cultivation technologies using Functional Plant Cultivation System (FPCS). EBARA Japan has been studying on the cultivation conditions in order to enhance the function of decease risk reduction in plants. Through the research and development activities, EBARA found the possibilities on the enhancement of functions. Quality and quantity of the products in term of bioactive compounds present in the plants may be affected by unforeseen environmental conditions, such as temperature, strong light and UV radiation. The main objective to develop this system is, to support? Functional Food Industry? as newly emerging field in agriculture business. To success the system, needs comprehensive applying agriculture biotechnologies, health biotechnologies and also information technologies, in agriculture. By this system, production of valuable bioactive compounds is an advantage, because the market size of functional food is increasing more and more in the future. (Author)

  16. Velvetbean and Bahiagrass as Rotation Crops for Management of Meloidogyne spp. and Heterodera glycines in Soybean

    OpenAIRE

    Weaver, D. B.; Rodríguez-Kábana, R.; Carden, E. L.

    1998-01-01

    Soybean (Glycine max) yield often is limited by the phytoparasitic nematodes Meloidogyne spp. and Heterodera glycines in the southeastern United States. We studied the effects of rotation with bahiagrass (Paspalum notatum), velvetbean (Mucuna pruiens), or continuous soybean, aldicarb, and soybean cultivar on yield and population densities in two fields infested with a mixture of Meloidogyne spp. and H. glycines. Velvetbean and bahiagrass reduced population levels of both nematode species to n...

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

    Science.gov (United States)

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

  18. Life cycle assessment of a willow bioenergy cropping system

    International Nuclear Information System (INIS)

    The environmental performance of willow biomass crop production systems in New York (NY) is analyzed using life cycle assessment (LCA) methodology. The base-case, which represents current practices in NY, produces 55 units of biomass energy per unit of fossil energy consumed over the biomass crop's 23-year lifetime. Inorganic nitrogen fertilizer inputs have a strong influence on overall system performance, accounting for 37% of the non-renewable fossil energy input into the system. Net energy ratio varies from 58 to below 40 as a function of fertilizer application rate, but application rate also has implications on the system nutrient balance. Substituting inorganic N fertilizer with sewage sludge biosolids increases the net energy ratio of the willow biomass crop production system by more than 40%. While CO2 emitted in combusting dedicated biomass is balanced by CO2 adsorbed in the growing biomass, production processes contribute to the system's net global warming potential. Taking into account direct and indirect fuel use, N2O emissions from applied fertilizer and leaf litter, and carbon sequestration in below ground biomass and soil carbon, the net greenhouse gas emissions total 0.68 g CO2 eq. MJbiomassproduced-1. Site specific parameters such as soil carbon sequestration could easily offset these emissions resulting in a net reduction of greenhouse gases. Assuming reasonable biomass transportation distance and energy conversion efficiencies, this study implies that generating electricity from willow biomass crops could produce 11 units of electricity per unit of fossil energy consumed. Results form the LCA support the assertion that willow biomass crops are sustainable from an energy balance perspective and contribute additional environmental benefits

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

    International Nuclear Information System (INIS)

    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)

  20. Long-Term Cropping System Effects on Soil Properties and on a Soil Quality Index

    Science.gov (United States)

    Intensive row-crop production can lead to soil degradation over time if insufficient biomass return, intensive tillage, or excessive erosion lead to depletion of soil organic C. Soil quality may be improved by incorporating forage crops or grazing into the rotation, adding manure or other organic so...

  1. 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.

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

    International Nuclear Information System (INIS)

    The mass of total carbon from Cambic Chernozem in the Moldavian Plain has recorded significant increases at higher than N140 P100 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 N140 P100 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-1 and the content in mobile phosphorus decreased from 51.6 to 36.8 P-Al, mg.kg-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-1) and 31%, respectively (11.8 P-Al mg.kg-1), against maize continuous cropping. (Author) 6 refs.

  3. 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.

  4. Climate change: Cropping system changes and adaptations

    Science.gov (United States)

    Climate change impacts the life of every person; however, there is little comprehensive understanding of the direct and indirect effects of climate change on agriculture. Since our food, feed, fiber, and fruit is derived from agricultural systems, understanding the effects of changing temperature, p...

  5. Yield of cotton/cowpea and sunflower/cowpea crop rotation systems during the reclamation process of a saline-sodic soil / Produtividade de sistemas de rotação algodão/ feijão-de-corda e girassol/ feijão-de-corda durante o processo de recuperação de um solo salino-sódico

    Scientific Electronic Library Online (English)

    Carlos H. C. de, Sousa; Claudivan F. de, Lacerda; Francisco L. B. da, Silva; Antonia L. R., Neves; Raimundo N. T., Costa; Hans R., Gheyi.

    2014-10-01

    Full Text Available O objetivo deste trabalho foi avaliar o uso de subsolagem, gesso agrícola e matéria orgânica, associados ao cultivo de algodão, girassol e feijão-de-corda em sistemas de rotação, visando à recuperação e o aproveitamento de um solo salino-sódico. Os tratamentos foram dispostos em um delineamento em b [...] locos casualizados, em parcelas subdivididas, com quatro repetições, durante dois ciclos. As parcelas foram formadas pelos tratamentos: T1. Subsolagem (S); T2. S + 20 Mg ha-1 de gesso (G); T3. S + 40 Mg ha-1 de matéria orgânica (MO); T4. S + 10 Mg ha-1 de G + 20 Mg ha-1 de MO; T5. S + 20 Mg ha-1 de G + 40 Mg ha-1 de MO, e as subparcelas corresponderam às rotações culturais algodão feijão-de-corda (AL/FC) e girassol feijão-de-corda (GI/FC). O emprego dos corretivos contribuiu para a diminuição dos níveis de salinidade e sodicidade do solo. O algodão não apresentou nenhuma resposta à aplicação dos tratamentos, enquanto a cultura do girassol foi favorecida pela aplicação de corretivos apenas no segundo ciclo. As maiores produtividades do feijão-de-corda no tratamento T5, no ciclo de 2009/2010, são indicativos de que as maiores doses de gesso e de matéria orgânica aplicadas neste tratamento aceleraram o processo de recuperação. Para os demais tratamentos com corretivos, verificou-se efeito benéfico para essa cultura apenas no segundo ciclo de produção, quando os valores se igualaram ao T5. Abstract in english The objective of this study was to evaluate the use of subsoiling, gypsum and organic matter associated with the cultivation of cotton, sunflower and cowpea in crop rotation, seeking the reclamation and use of a saline-sodic soil. The treatments were arranged in a randomized block design in split pl [...] ots with four replications, during two crop cycles (2009/2010 and 2010/2011). The plots were formed by the treatments: T1. Subsoiling (S); T2. S + 20 Mg ha-1 of gypsum; T3. S + 40 Mg ha-1 of organic matter; T4. S + 10 Mg ha-1 of gypsum + 20 Mg ha-1 of organic matter; T5. S + 20 Mg ha-1 of gypsum + 40 Mg ha-1 of organic matter and the sub-plots consisted of the cotton-cowpea (C/CP) and sunflower-cowpea (S/CP) crop rotation. The use of gypsum and organic matter contributed to decrease the soil salinity and sodicity. Cotton was not affected by the treatments, while the sunflower crop was favored by the application of amendments only in the second production cycle. Higher yields of cowpea in T5 treatment, during the 2009/2010 cycle, are indicative that higher doses of gypsum and organic matter applied in this treatment accelerate the reclamation process. For other treatments with amendment application there was a beneficial effect for this crop only in the second cycle, when the values of productivity were similar to T5.

  6. 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

    2009-04-01

    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.

  7. Rotating capacitor system for the tokamak experimental power reactor

    International Nuclear Information System (INIS)

    A conceptual design for a rotating capacitor system which uses many concentric drum-type homopolar generators in a single magnet yoke is presented. An example system is described which can develop 72,530 V and store 1150 MJ

  8. Soil/plant nutrition in lowland cropping systems

    International Nuclear Information System (INIS)

    Farming system approaches have led to rapid changes in agricultural systems in Asia and the Pacific. They have increased food and other agricultural commodities as well as developing awareness of scarcity of natural resources, environmental degradation and dissemination of new agricultural technology. This paper reviews and summarizes recent research and technology on soil/plant nutrition with emphasis on nitrogen, phosphorus, and sulphur in rice-based lowland cropping systems in Asia and the Pacific region. It mainly focuses on the application of isotopes 15N, 32P and 35S in such studies, but some current research using conventional methods is also covered. A search of the literature shows that technology studies have mostly concentrated on identifying improved varieties for short duration rice, improving tillage practices, pest and weed management. Research in soil/plant nutrition in rice-based cropping systems particularly using isotopes, is limited. (author). 51 refs, 2 tabs

  9. Impact of Shortened Crop Rotation of Oilseed Rape on Soil and Rhizosphere Microbial Diversity in Relation to Yield Decline

    Science.gov (United States)

    Hilton, Sally; Bennett, Amanda J.; Keane, Gary; Bending, Gary D.; Chandler, David; Stobart, Ron; Mills, Peter

    2013-01-01

    Oilseed rape (OSR) grown in monoculture shows a decline in yield relative to virgin OSR of up to 25%, but the mechanisms responsible are unknown. A long term field experiment of OSR grown in a range of rotations with wheat was used to determine whether shifts in fungal and bacterial populations of the rhizosphere and bulk soil were associated with the development of OSR yield decline. The communities of fungi and bacteria in the rhizosphere and bulk soil from the field experiment were profiled using terminal restriction fragment length polymorphism (TRFLP) and sequencing of cloned internal transcribed spacer regions and 16S rRNA genes, respectively. OSR cropping frequency had no effect on rhizosphere bacterial communities. However, the rhizosphere fungal communities from continuously grown OSR were significantly different to those from other rotations. This was due primarily to an increase in abundance of two fungi which showed 100% and 95% DNA identity to the plant pathogens Olpidium brassicae and Pyrenochaeta lycopersici, respectively. Real-time PCR confirmed that there was significantly more of these fungi in the continuously grown OSR than the other rotations. These two fungi were isolated from the field and used to inoculate OSR and Brassica oleracea grown under controlled conditions in a glasshouse to determine their effect on yield. At high doses, Olpidium brassicae reduced top growth and root biomass in seedlings and reduced branching and subsequent pod and seed production. Pyrenochaeta sp. formed lesions on the roots of seedlings, and at high doses delayed flowering and had a negative impact on seed quantity and quality. PMID:23573215

  10. 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)

    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 m2 of land kWh?1; land conversion released 2.8 ± 0.2 t CO2e 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 m2kWhe-1 for the gasification and 1.1 m2kWhe-1 for the combustion technology. Converting agricultural land into the SRWC plantation released 2.8 ± 0.2 t CO2e ha?1, which represented ?89% of the total GHG emissions (256–272 g CO2e kWhe-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 sustainable production of renewable energy with significant climate benefits

  11. SOIL FUNGISTASIS AGAINST FUSARIUM GRAMINEARUM UNDER DIFFERENT CROP MANAGEMENT SYSTEMS

    OpenAIRE

    Bruno Brito Lisboa; Cimélio Bayer; Luciane Maria Pereira Passaglia; Flávio Anastácio Oliveira Camargo; Anelise Beneduzi; Adriana Ambrosini; Luciano Kayser Vargas

    2015-01-01

    Soil management, in terms of tillage and cropping systems, strongly influences the biological properties of soil involved in the suppression of plant diseases. Fungistasis mediated by soil microbiota is an important component of disease-suppressive soils. We evaluated the influence of different management systems on fungistasis against Fusarium graminearum, the relationship of fungistasis to the bacterial profile of the soil, and the possible mechanisms involved in this process. Samples were ...

  12. Adaptation strategies of Mediterranean cropping systems to climate change

    OpenAIRE

    Mula, Laura

    2014-01-01

    The EPIC simulation model was used to assess the impact of climate change (CC) on intensive and extensive Mediterranean forage systems to study the effects of CC and adaptation strategies. The intensive cropping system (corn silage – Italian ryegrass) is linked to dairy cattle farms. As first step the EPIC model was calibrated based on experimental data. After calibration the EPIC model was used to perform simulations with different climate scenarios (present and future climate) with diffe...

  13. Suspension System Provides Independent Translation And Rotation

    Science.gov (United States)

    Heeg, Jennifer

    1994-01-01

    Spring suspension provides one translational and one rotational degree of freedom. Suspension used to provide for pitching and plunging movements of airfoil in wind tunnel. Translational freedom provided by two thin, flat steel spring tines, clamped at one end to stationary block fixed to ceiling of wind tunnel, and clamped to movable block at other end.

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

    Science.gov (United States)

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

    2014-12-01

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

  15. Thermodynamics in rotating systems -- analysis of selected examples

    CERN Document Server

    Güémez, Julio

    2014-01-01

    We solve a set of selected exercises on rotational motion requiring a mechanical and thermodynamical analysis. When non-conservative forces or thermal effects are present, a complete study must use the first law of thermodynamics together with the Newton's second law. The latter is here better expressed in terms of an `angular' impulse-momentum equation (Poinsot-Euler equation), or, equivalently, in terms of a `rotational' pseudo-work-energy equation. Thermodynamical aspects in rotational systems, when e.g. frictional forces are present or when there is a variation of the rotational kinetic energy due to internal sources of energy, are discussed.

  16. Thermodynamics in rotating systems—analysis of selected examples

    Science.gov (United States)

    Güémez, J.; Fiolhais, M.

    2014-01-01

    We solve a set of selected exercises on rotational motion requiring a mechanical and thermodynamical analysis. When non-conservative forces or thermal effects are present, a complete study must use the first law of thermodynamics together with Newton’s second law. The latter is here better expressed in terms of an ‘angular’ impulse-momentum equation (Poinsot-Euler equation), or, equivalently, in terms of a ‘rotational’ pseudo-work-energy equation. Thermodynamical aspects in rotational systems, when e.g. frictional forces are present or when there is a variation of the rotational kinetic energy due to internal sources of energy, are discussed.

  17. Thermodynamics in rotating systems—analysis of selected examples

    International Nuclear Information System (INIS)

    We solve a set of selected exercises on rotational motion requiring a mechanical and thermodynamical analysis. When non-conservative forces or thermal effects are present, a complete study must use the first law of thermodynamics together with Newton’s second law. The latter is here better expressed in terms of an ‘angular’ impulse–momentum equation (Poinsot–Euler equation), or, equivalently, in terms of a ‘rotational’ pseudo-work–energy equation. Thermodynamical aspects in rotational systems, when e.g. frictional forces are present or when there is a variation of the rotational kinetic energy due to internal sources of energy, are discussed. (paper)

  18. Prediction and removal of rotation noise in airborne EM systems

    Science.gov (United States)

    Kratzer, Terence 12Macnae, James

    2014-03-01

    We aim to eliminate or reduce significant impediments to conductive target detection and conductive cover penetration in airborne electromagnetic (AEM) systems. Existing limitations come from the very high noise encountered at low base frequencies, caused by rotations of vector magnetic field sensors in the Earth's magnetic field. We use the output of tri-axial rotation-rate sensors to predict and subtract the rotation noise from rigidly coupled ARMIT magnetic field sensors. The approach is successful in reducing rotation noise by one to two orders of magnitude at low frequencies.

  19. A description of rotations for DEM models of particle systems

    Science.gov (United States)

    Campello, Eduardo M. B.

    2015-06-01

    In this work, we show how a vector parameterization of rotations can be adopted to describe the rotational motion of particles within the framework of the discrete element method (DEM). It is based on the use of a special rotation vector, called Rodrigues rotation vector, and accounts for finite rotations in a fully exact manner. The use of fictitious entities such as quaternions or complicated structures such as Euler angles is thereby circumvented. As an additional advantage, stick-slip friction models with inter-particle rolling motion are made possible in a consistent and elegant way. A few examples are provided to illustrate the applicability of the scheme. We believe that simple vector descriptions of rotations are very useful for DEM models of particle systems.

  20. Convective heat and mass transfer in rotating disk systems

    Energy Technology Data Exchange (ETDEWEB)

    Shevchuk, Igor V. [MBtech Powertrain GmbH, Fellbach-Schmiden (Germany)

    2009-07-01

    The book describes results of investigations of a series of convective heat-and-mass transfer problems in rotating-disk systems, namely, over free rotating disks, under conditions of transient heat transfer, solid-body rotation of fluid, orthogonal flow impingement onto a disk, swirl radial flow between parallel co-rotating disks, in cone-disk systems and for Prandtl and Schmidt numbers larger than one. Methodology used included integral methods, self-similar and approximate analytical solutions, as well as CFD. The book is aimed at the professional audience of academic researchers, industrial R and D engineers, university lecturers and graduate/postgraduate students working in the area of rotating-disk systems. (orig.)

  1. Planting dates for multiple cropping of biofuel feedstock and specialty crops

    Science.gov (United States)

    It is necessary to determine planting and harvesting windows in order to develop production systems for biofuel feedstock and specialty crops in rotation. The biodiesel feedstock crops Canola and Sunflower; and the bioethanol feedstock crops Sorghum and Sweet corn were established at various dates ...

  2. 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.

  3. In vitro mutation system for crop improvement

    International Nuclear Information System (INIS)

    Biotechnology based on plant tissue culture is complementary to conventional breeding technologies, not a substitute for them. Effective incorporation of new biotechnologies into plant breeding programmes is dependent on the plant species and the breeding objectives. Tissue culture techniques that ensure genetic stability (e.g. shoot tip and nodal cultures) are particularly useful for in vitro mutation induction and mutant plant regeneration. Direct organogenesis of adventitious buds and/or somatic embryogenesis on cultured explants offers a unique potential to dissolve chimerism and to produce homohistont mutants. In mutation breeding, non-heritable somaclonal variation should be avoided in order to minimize complications in the selection and genetic stability of mutants. Application of mutagens during in vitro culture requires certain modification, depending on the explant and the mutagen used. The advantages are large populations of individuals (propagula, cells and tissue) which can be treated before regeneration into intact plants. Experience with plant tissue culture shows several disadvantages in this system of mutation breeding. The main limitations are inadequate techniques for early screening and in vitro selection. Too little is known about the plant developmental processes and host-pathogen interaction to permit the breeder to design an effective means of selecting desirable mutants. (author). 25 refs, 9 figs

  4. 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 ...

  5. Efeitos da rotação de culturas na incidência de podridões radiciais e na produtividade da soja / Effects of crop rotation on root rot incidence and on soybean grain yield

    Scientific Electronic Library Online (English)

    Erlei Melo, Reis; Marivane, Segalin; Nara Lucia, Moraes; Valeria Cecília, Ghissi.

    2014-03-01

    Full Text Available Em experimentos conduzidos no campo, no sistema plantio direto, nas safras de verão de 2003/04, 2004/05 e 2005/06 foram avaliados os efeitos de culturas de inverno, da rotação e da monocultura sobre a emergência de plântulas, na incidência de podridões radiciais e no rendimento de grãos da soja. Dem [...] onstrou-se não haver efeitos das culturas de inverno sobre a emergência de plântulas da soja. Quanto à incidência de podridões radiciais em monocultura foi registrada uma intensidade de até 99,2%. O maior rendimento de grãos foi obtido na soja cultivada em rotação com uma safra com milho. Os fungos isolados do sistema radicial de plantas infectadas foram, Macrophomina phaseolina, Phomopsis sp., Fusarium spp. e Colletotrichum truncata. O solo da área experimental pode ser considerado supressivo aos fatores que reduzem a germinação, a emergência de plântulas e de morte de plântulas/plantas de soja. Quanto ao seu efeito em reduzir as podridões radiciais, ainda não se detectou efeito supressivo, porém a rotação da soja com o milho reduziu a incidência de podridões radiciais e aumentou o rendimento de grãos da soja. Abstract in english In experiments carried out in the field, under no-till planting system, in 2003/04, 2004/05 and 2005/06 summer growing seasons, the effects of winter crops, rotation and monoculture on seedling emergence, root rot incidence and soybean grain yield were assessed. There were no effects of winter crops [...] on soybean seedling emergence. As to root rot incidence on monoculture, an intensity of up to 99.2% was recorded. Grain yield was highest when soybean was cultivated in one season of rotation with corn. The fungi isolated from the root system of infected plants were Macrophomina phaseolina, Phomopsis sp., Fusarium spp. and Colletotrichum truncata. The soil at the experimental area can be considered suppressive to factors that reduce soybean germination, seedling emergence, and seedling/plant death. Considering its effect in reducing root rot, a suppressive action has not been detected yet; however, soybean rotation with corn reduced root rot incidence and increased soybean grain yield.

  6. Demanda de tração em haste sulcadora na integração lavoura-pecuária com diferentes pressões de pastejo e sua relação com o estado de compactação do solo / Draft requirement in direct drilling in crop and cattle rotation systems using different grazing pressures and its relation to soil compactness status

    Scientific Electronic Library Online (English)

    Osmar, Conte; Renato, Levien; Carlos R., Trein; Carla T. C., Cepik; Henrique, Debiasi.

    2007-04-01

    Full Text Available Conduziu-se um experimento com integração lavoura-pecuária em Latossolo Vermelho distroférrico para avaliar o esforço de tração em hastes sulcadoras de adubo utilizadas em semeadura direta, atuando em diferentes profundidades e intensidades de pastejo, bem como o efeito desse último fator sobre o es [...] tado de compactação do solo. Os tratamentos principais foram constituídos pelas alturas da pastagem de inverno (aveia + azevém): 0,10; 0,20; 0,30 e 0,40 m e sem pastejo, obtidas variando-se a carga animal, e os tratamentos secundários foram duas profundidades de atuação da haste sulcadora de adubo: 0,12 e 0,15 m. A massa seca de raízes da pastagem, na camada de 0 a 0,12 m, aumentou com o incremento na intensidade de pastejo. Analisando os valores de resistência mecânica do solo à penetração, o efeito do pastejo foi detectado até 0,12 m, sendo crescentes com a intensidade de pastejo. A força de tração demandada pelas hastes aumentou de 1.900 para 4.300 N (120%), quando a profundidade de trabalho passou de 0,12 para 0,15 m. O esforço de tração nas hastes sulcadoras também foi maior quanto maior a carga de animais sobre a pastagem, embora as diferenças tenham sido significativas apenas entre os tratamentos sem pastejo e os mantidos a alturas de 0,10 e 0,20 m. Os valores de resistência do solo à penetração e de esforço de tração demandado pelas hastes sulcadoras apresentaram correlação significativa. Abstract in english An experiment was carried out with crop and cattle rotation in an Oxisoil, in Tupanciretã - RS, which aimed to evaluate the draft effort in fertilizer direct drillings used in direct seeding, working at different depths and intensities of fields under different grazing pressures. Grazing pressure ef [...] fects on soil compactness were also assessed. The main treatments were grazing maintaining 0.10, 0.20, 0.30, 0.40 m pasture (Lolium multiflorum + Avena strigosa) without grazing, height (adjusting the number of cows on the plots) and two working depths of fertilizer shanks: 0.12 m and 0.15 m. Root dry matter in the superficial layer (0.0 - 0.12 m) was increased when higher grazing pressures were used. Soil resistance to a penetrometer showed increased values at higher grazing pressures; it was detected until 0.12 m depth. Draft requirement of fertilizer shanks increased from 1,900 to 4,300 N (120%) when the working depth changed from 0.12 m to 0.15 m condition. Draft demand by fertilizer shanks was higher on soils under higher pressures as well, but the absolute values showed that only treatments with remaining heights of 0.10 and 0.20 m were different from those found without grazing systems. Soil resistance to penetrometer and power demand by fertilizer shanks was closely related.

  7. Demanda de tração em haste sulcadora na integração lavoura-pecuária com diferentes pressões de pastejo e sua relação com o estado de compactação do solo Draft requirement in direct drilling in crop and cattle rotation systems using different grazing pressures and its relation to soil compactness status

    Directory of Open Access Journals (Sweden)

    Osmar Conte

    2007-04-01

    Full Text Available Conduziu-se um experimento com integração lavoura-pecuária em Latossolo Vermelho distroférrico para avaliar o esforço de tração em hastes sulcadoras de adubo utilizadas em semeadura direta, atuando em diferentes profundidades e intensidades de pastejo, bem como o efeito desse último fator sobre o estado de compactação do solo. Os tratamentos principais foram constituídos pelas alturas da pastagem de inverno (aveia + azevém: 0,10; 0,20; 0,30 e 0,40 m e sem pastejo, obtidas variando-se a carga animal, e os tratamentos secundários foram duas profundidades de atuação da haste sulcadora de adubo: 0,12 e 0,15 m. A massa seca de raízes da pastagem, na camada de 0 a 0,12 m, aumentou com o incremento na intensidade de pastejo. Analisando os valores de resistência mecânica do solo à penetração, o efeito do pastejo foi detectado até 0,12 m, sendo crescentes com a intensidade de pastejo. A força de tração demandada pelas hastes aumentou de 1.900 para 4.300 N (120%, quando a profundidade de trabalho passou de 0,12 para 0,15 m. O esforço de tração nas hastes sulcadoras também foi maior quanto maior a carga de animais sobre a pastagem, embora as diferenças tenham sido significativas apenas entre os tratamentos sem pastejo e os mantidos a alturas de 0,10 e 0,20 m. Os valores de resistência do solo à penetração e de esforço de tração demandado pelas hastes sulcadoras apresentaram correlação significativa.An experiment was carried out with crop and cattle rotation in an Oxisoil, in Tupanciretã - RS, which aimed to evaluate the draft effort in fertilizer direct drillings used in direct seeding, working at different depths and intensities of fields under different grazing pressures. Grazing pressure effects on soil compactness were also assessed. The main treatments were grazing maintaining 0.10, 0.20, 0.30, 0.40 m pasture (Lolium multiflorum + Avena strigosa without grazing, height (adjusting the number of cows on the plots and two working depths of fertilizer shanks: 0.12 m and 0.15 m. Root dry matter in the superficial layer (0.0 - 0.12 m was increased when higher grazing pressures were used. Soil resistance to a penetrometer showed increased values at higher grazing pressures; it was detected until 0.12 m depth. Draft requirement of fertilizer shanks increased from 1,900 to 4,300 N (120% when the working depth changed from 0.12 m to 0.15 m condition. Draft demand by fertilizer shanks was higher on soils under higher pressures as well, but the absolute values showed that only treatments with remaining heights of 0.10 and 0.20 m were different from those found without grazing systems. Soil resistance to penetrometer and power demand by fertilizer shanks was closely related.

  8. Black Locust (Robinia pseudoacacia L. Short-Rotation Energy Crops in Hungary: A Review

    Directory of Open Access Journals (Sweden)

    Károly Rédei

    2010-01-01

    Full Text Available The importance of the establishment of short-rotation tree plantations for fuel production has been of international interest for many years. In this context, in Hungary, these plantations have been conducted for a long time. In this country, the black locust (Robinia pseudoacacia L. is one of the most important stand-forming tree species, covering approximately 23% of the forested land (410 000 ha and providing about 19% of the annual timber output. This paper describes an experimental energy plantation that was established in Helvécia (Central-Hungary, sand-soil region using common black locust and its improved cultivars. The site may be considered as representative of an average yield class for black locust in Hungary. The experimental plantation was established with a spacing of 1.5 m x 1.0 m and included common black locust and two cultivars, 'Üll?i' and 'Jászkiséri, as well as a plot regenerated by coppice. At the age of 7, the highest annual increment in stem oven-dry mass was produced by the cultivar 'Üll?i' (9.7 Mg ha-1 yr-1 followed by the common black locust (8.4 Mg ha-1 yr-1 and the cultivar 'Jászkiséri (7.6 Mg ha-1 yr-1. In the plot of coppice origin, dendromass ranged from 6 to 8 Mg ha-1 yr-1 on an average.

  9. An Ultrasonic System for Weed Detection in Cereal Crops

    OpenAIRE

    Dionisio Andújar; Roland Gerhards; Martin Weis

    2012-01-01

    Site-specific weed management requires sensing of the actual weed infestation levels in agricultural fields to adapt the management accordingly. However, sophisticated sensor systems are not yet in wider practical use, since they are not easily available for the farmers and their handling as well as the management practice requires additional efforts. A new sensor-based weed detection method is presented in this paper and its applicability to cereal crops is evaluated. An ultrasonic distance ...

  10. Plant nutrient and water balance studies under legume-cereal rotation systems

    International Nuclear Information System (INIS)

    A two-year cycle of crop rotation experiments with at least three main treatments of cereal-cereal, legume-cereal and fallow-cereal treatments was outlined. The water balance approach was utilized to estimate crop water consumption and to compare different crop rotation systems, in view of water conservation and of increasing efficient use of scarcely available water under rainfed areas of Middle-Eastern Countries, with low and erratic rainfall characteristics. The use of the neutron scattering technique was recommended for easy monitoring of changes in soil water storage, as one of the key field data required in the water balance equation. The use of 15N-labelled fertilizers provided a unique tool allowing to separately study the behaviour of N-fertilizer as well as soil N. In addition, the quantification of residual fertilizer N was possible. Also, the use of labelled N allowed to quantify the amount of biologically fixed N2. (author). 7 refs, 4 figs, 1 tab

  11. 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

    Scientific Electronic Library Online (English)

    Demóstenes Marcos Pedrosa de, Azevedo; Juan, Landivar; Robson Macedo, Vieira; Daryl, Moseley.

    1999-03-01

    Full Text Available 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 de N para o sorgo. As rotações sorgo/algodão e sorgo/soja proporcionaram efeito positivo no rendimento de sorgo. Este efeito foi atribuído à maior concentração de N nestas seqüências. Abstract in english 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.

  12. 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 de N para o sorgo. As rotações sorgo/algodão e sorgo/soja proporcionaram efeito positivo no rendimento de sorgo. Este efeito foi atribuído à maior concentração de N nestas seqüências.

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

    Directory of Open Access Journals (Sweden)

    Arminda Moreira de Carvalho

    2014-06-01

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

  14. Three-parameter error analysis method based on rotating coordinates in rotating birefringent polarizer system

    Science.gov (United States)

    Cao, Junjie; Jia, Hongzhi

    2015-11-01

    We propose error analysis using a rotating coordinate system with three parameters of linearly polarized light—incidence angle, azimuth angle on the front surface, and angle between the incidence and vibration planes—and demonstrate the method on a rotating birefringent prism system. The transmittance and angles are calculated plane-by-plane using a birefringence ellipsoid model and the final transmitted intensity equation is deduced. The effects of oblique incidence, light interference, beam convergence, and misalignment of the rotation and prism axes are discussed. We simulate the entire error model using MATLAB and conduct experiments based on a built polarimeter. The simulation and experimental results are consistent and demonstrate the rationality and validity of this method.

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

    Science.gov (United States)

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

    1997-01-01

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

  16. A spatial ecology study on the effects of field conditions and crop rotation on the incidence of Plectris aliena (Coleoptera: Scarabaeidae) grub damage to sweetpotato roots.

    Science.gov (United States)

    Brill, Nancy L; Osborne, Jason; Abney, Mark R

    2013-10-01

    A farmscape study was conducted in commercial sweetpotato (Ipomoea batatas (L.) Lam) fields in Columbus County, NC, in 2010 and 2011 to investigate the effects of the following field conditions: soil drainage class, soil texture, field size, border habitat, land elevation, and the previous year's crop rotation on the incidence of damage caused by Plectris aliena Chapman (Coleoptera:Scarabaeidae) larval feeding. Soil drainage and crop rotation significantly affected the incidence of damage to roots, with well drained soils having a low estimated incidence of damaged roots (0.004) compared with all other drainage classes (0.009-0.011 incidence of damaged roots). Fields with soybeans [Glycine max (L.) Merr] planted the preceding year had the highest incidence of root damage (0.15) compared with all other crops. The effects of border habitats, which were adjacent to grower fields where roots were sampled, showed that as the location of the roots was closer to borders of soybean (planted the year before) or grass fields, the chance of damage to roots decreased. Results indicate that growers can use crop rotation as a management technique and avoid planting sweetpotatoes the year after soybeans to reduce the incidence of P. aliena larval feeding on sweetpotato roots. Environmental conditions such as fields with poor drainage and certain border habitats may be avoided, or selected, by growers to reduce risk of damage to roots by P. aliena. PMID:24331614

  17. An expert system for vibration based diagnostics of rotating machines

    International Nuclear Information System (INIS)

    Very often changes in the mechanical condition of the rotating machinery can be observed as changes in its vibration. This paper presents an expert system for vibration-based diagnosis of rotating machines by describing the architecture of the developed prototype system. The importance of modelling the problem solving knowledge as well as the domain knowledge is emphasized by presenting the knowledge in several levels

  18. SOIL FUNGISTASIS AGAINST FUSARIUM GRAMINEARUM UNDER DIFFERENT CROP MANAGEMENT SYSTEMS

    Directory of Open Access Journals (Sweden)

    Bruno Brito Lisboa

    2015-02-01

    Full Text Available Soil management, in terms of tillage and cropping systems, strongly influences the biological properties of soil involved in the suppression of plant diseases. Fungistasis mediated by soil microbiota is an important component of disease-suppressive soils. We evaluated the influence of different management systems on fungistasis against Fusarium graminearum, the relationship of fungistasis to the bacterial profile of the soil, and the possible mechanisms involved in this process. Samples were taken from a long-term experiment set up in a Paleudult soil under conventional tillage or no-tillage management and three cropping systems: black oat (Avena strigose L. + vetch (Vicia sativa L./maize (Zea mays L. + cowpea (Vigna sinensis L., black oat/maize, and vetch/maize. Soil fungistasis was evaluated in terms of reduction of radial growth of F. graminearum, and bacterial diversity was assessed using ribosomal intergenic spacer analysis (RISA. A total of 120 bacterial isolates were obtained and evaluated for antibiosis, and production of volatile compounds and siderophores. No-tillage soil samples showed the highest level of F. graminearum fungistasis by sharply reducing the development of this pathogen. Of the cropping systems tested, the vetch + black oat/maize + cowpea system showed the highest fungistasis and the oat/maize system showed the lowest. The management system also affected the genetic profile of the bacteria isolated, with the systems from fungistatic soils showing greater similarity. Although there was no clear relationship between soil management and the characteristics of the bacterial isolates, we may conclude that antibiosis and the production of siderophores were the main mechanisms accounting for fungistasis.

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

    Directory of Open Access Journals (Sweden)

    Carlos Marques

    2015-03-01

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

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

    Scientific Electronic Library Online (English)

    Carlos, Marques; Fátima, Baptista; Luis Leopoldo, Silva; Dina, Murcho; Maurícia, Rosado.

    2015-03-01

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

  1. 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. PMID:23751946

  2. Magnetic nanofluids and magnetic composite fluids in rotating seal systems

    Energy Technology Data Exchange (ETDEWEB)

    Borbath, T; Borbath, I; Boros, T [Roseal Corporation, Nicolae Balcescu street, no. 5/A, Odorheiu Secuiesc, 535600 (Romania); Bica, D; Vekas, L [Lab. Magnetic Fluids, Center for Fundamental and Advanced Technical Research, Romanian Academy, Timisoara Division (LMF-CFATR-RATD) Mihai Viteazul Bvd., no. 24, Timisoara, 300223 (Romania); Potencz, I, E-mail: office@roseal.topnet.r [National Center for Engineering of Systems with Complex Fluids, University Politehnica Timisoara, Mihai Viteazul Bvd., no. 1, Timisoara, 300222 (Romania)

    2010-08-15

    Recent results are presented concerning the development of magnetofluidic leakage-free rotating seals for vacuum and high pressure gases, evidencing significant advantages compared to mechanical seals. The micro-pilot scale production of various types of magnetizable sealing fluids is shortly reviewed, in particular the main steps of the chemical synthesis of magnetic nanofluids and magnetic composite fluids with light hydrocarbon, mineral oil and synthetic oil carrier liquids. The behavior of different types of magnetizable fluids in the rotating sealing systems is analyzed. Design concepts, some constructive details and testing procedures of magnetofluidic rotating seals are presented such as the testing equipment. The main characteristics of several magnetofluidic sealing systems and their applications will be presented: vacuum deposition systems and liquefied gas pumps applications, mechanical and magnetic nanofluid combined seals, gas valves up to 40 bar equipped by rotating seal with magnetic nanofluids and magnetic composite fluids.

  3. Effects of broad-leaf crop frequency in various rotations on soil organic C and N, and inorganic N in a Dark Brown soil

    OpenAIRE

    Sukhdev S. Malhi; R. L. Lemke; S.A. Brandt

    2012-01-01

    The objective of this study was to determine the impact of frequency of broad-leaf crops canola and pea in various crop rotations on pH, total organic C (TOC), total organic N (TON), light fraction organic C (LFOC) and light fraction organic N (LFON) in the 0 - 7.5 and 7.5 - 15 cm soil depths in autumn 2009 after 12 years (1998-2009) on a Dark Brown Chernozem (Typic Boroll) loam at Scott, Saskatchewan, Canada. The field ex-periment contained monoculture canola (herbicide tolerant and blackleg...

  4. COVER CROP SELECTION AND MANAGEMENT FOR MIDWEST FARMING SYSTEMS

    Science.gov (United States)

    Winter cover crops are planted shortly before or soon after harvest of the cash crop and are killed before or soon after planting of the next cash crop. Cereal grains, such as oat, barley, winter wheat, triticale, and rye are excellent cover crops because they grow rapidly in cool weather, withstan...

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

    CERN Document Server

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

    2013-01-01

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

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

    Science.gov (United States)

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

    2014-05-01

    Sources of soil organic matter (SOM) input to the soil in agro-ecosystems are typically crop residues. The question arises how removing crop residues from a field influences soil carbon sequestration. We investigated four long-term maize and grass dominant cropping systems each with a different residue management. Under silage maize (SM) all stover is removed from the field and only a stubble remains, whereas under grain maize (GM) only the grains are harvested and all stover is returned to the soil. Fields with a history of at least 15 consecutive years of either SM (with or without a second annual crop of Italian ryegrass) or GM, and fields under permanent grass were selected from a geodatabase that covers 15 years of crop rotation for all of the ca. 500,000 agricultural fields in Flanders. For each cropping system 10 fields were sampled (40 in total) following the area-frame randomized soil sampling (AFRSS) protocol (Stolbovoy et al., 2007). For 6 out of 10 fields only the topsoil was sampled (0-30 cm), whereas for the 4 other fields both topsoil and subsoil (30-60 cm and 60-90 cm) were sampled. The total soil organic carbon (SOC) and nitrogen content and the stable carbon isotope ratio (13C/12C) were determined for each soil sample. From each field 1 topsoil sample was fractionated by the Zimmermann fractionation procedure (Zimmermann et al., 2007) which distinguishes between 5 different SOC fractions (POM, DOC, silt and clay associated SOC, chemically resistant SOC, SOC associated with sand fraction). Besides analysis of the SOC and nitrogen content of each fraction, the origin of the carbon was determined through isotope-ratio mass spectrometry. Although there was no significant difference between SM and GM regarding the total SOC stock for the upper 30 cm (ca. 75 à 80 Mg C.ha-1), fields under continuous GM contained in the 0-30 cm layer 60% more maize-derived C4-SOC as compared to fields under continuous SM (ca. 14 and 9 Mg C.ha-1 respectively). Significant differences could also be demonstrated for the carbon fractions of soils with different cropping histories. Each fraction of a GM-topsoil contained significantly more C4-SOC as compared to a SM-topsoil (with or without a second annual crop) with the sizes of the fractions being equal. The more labile POM- en DOC-fractions accounted for the biggest part of the maize C4-SOC detected in the bulk sample, whereas the silt and clay associated SOC and chemically resistant SOC consisted mainly out of old grass C3-SOC. For the deeper soil layers no significant differences could be demonstrated between GM and SM, neither for the total SOC stock nor for the C4-SOC stock. Our results suggest that the soils with maize cropping systems in Flanders are near carbon saturation, such that crop residue management does not influence the total amount, but rather the quality of the carbon sequestered. Stolbovoy, V., Montanarella, L., Filippi, N., Jones, A., Gallego, J., and Grassi, G. (2007). Soil sampling protocol to certify the changes of organic carbon stock in mineral soil of the European Union. Version 2. EUR 21576 EN/2. Office for Official Publications of the European Communities, Luxembourg. 56p. Zimmermann, M., Leifeld, J., Schmidt, M.W.I., Smith, P., and Fuhrer, J. (2007). Measured soil organic matter fractions can be related to pools in the RothC model. European Journal of Soil Science, 58: 658-667.

  7. Soil Organic Carbon sequestration in agricultural soils: the combined impact of no tillage continuous cropping and no tillage crop-pasture rotation on the level of soil organic carbon in the unfractionated soil and three size fractions and on the C:N ratio in an Uruguayan Agriudoll.

    OpenAIRE

    Zierfuss, T.

    2014-01-01

    Sequestration of atmospheric carbon in agricultural soils in the form of soil organic carbon (SOC) can help fight climate change and improve soil fertility. This can be achieved by changing current agricultural management practices to new practices that store more carbon in the soil. Two promising practices are no-tillage and crop pasture rotation. This thesis evaluated the combined effect of these two practices by comparing no-tillage continuous cropping, no-tillage crop pasture rotation wit...

  8. ECONOMIC OPPORTUNITIES FOR REDUCING NET GLOBAL WARMING POTENTIAL IN IRRIGATED CROPPING SYSTEMS IN NORTHEASTERN COLORADO

    Science.gov (United States)

    A cropping systems field study initiated in 1999 was used in this analysis to evaluate the economic feasibility of achieving reductions in net global warming potential through changes in cropping system management. Crop yield and management information collected from 2000-2005 were used to estimate ...

  9. A model for an innovative crop protection system in the future illustrated for maize

    OpenAIRE

    Zijlstra, C.

    2010-01-01

    To show how innovative techniques for monitoring and precision spraying can be used we have developed a generic model for crop protection system for future high tech cropping systems. We have illustrated how to work with it taking maize as a model crop

  10. Soil C and N fractions in cropping systems integrated with livestock

    Science.gov (United States)

    Integration of livestock in cropping systems of the southeastern USA could increase farm income diversity and improve nutrient cycling dynamics to increase resource efficiency. A long-term pasture was terminated and planted to cropping systems with and without cattle grazing of cover crops to deter...

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

    Science.gov (United States)

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

  12. Machine protection system for rotating equipment and method

    Science.gov (United States)

    Lakshminarasimha, Arkalgud N. (Marietta, GA); Rucigay, Richard J. (Marietta, GA); Ozgur, Dincer (Kennesaw, GA)

    2003-01-01

    A machine protection system and method for rotating equipment introduces new alarming features and makes use of full proximity probe sensor information, including amplitude and phase. Baseline vibration amplitude and phase data is estimated and tracked according to operating modes of the rotating equipment. Baseline vibration and phase data can be determined using a rolling average and variance and stored in a unit circle or tracked using short term average and long term average baselines. The sensed vibration amplitude and phase is compared with the baseline vibration amplitude and phase data. Operation of the rotating equipment can be controlled based on the vibration amplitude and phase.

  13. Cryogenic cooling with cryocooler on a rotating system

    OpenAIRE

    Oguri, Shugo; Choi, Jihoon; Kawai, Masanori; Tajima, Osamu

    2013-01-01

    We developed a system that continuously maintains a cryocooler for long periods on a rotating table. A cryostat that holds the cryocooler is set on the table. A compressor is located on the ground and supplies high-purity (> 99.999%) and high-pressure (1.7 MPa) helium gas and electricity to the cryocooler. The operation of the cryocooler and other instruments requires the development of interface components between the ground and rotating table. A combination of access holes...

  14. INFLUENCE OF COVER CROPS IN ROTATION ON IMPROVING OKRA (ABELMOSCHUS ESCULENTUS L.) YIELD AND SUPPRESSING PARASITIC NEMATODES

    Science.gov (United States)

    The influence of growing and incorporating summer cover crops on subsequent vegetable crop production and on population densities of the root-knot nematode (Meloidogyne incognita) was investigated in field and pot experiments at Homestead, Florida. The cover crops utilized in the field and pot exper...

  15. Diagnostic system based on vibration measurement for rotating machines

    International Nuclear Information System (INIS)

    Large scale electric power plants are equipped with a number of the rotating machines which occupy important positions in the plant system. Therefore, respective users assign several countermeasure to improve their reliability and availability as well, among which the maintenance of such equipment for efficient operation as well as the promotion and strengthening of precautions for safety have now become system requirements. In the above context, we have developed a machinery diagnostic system for rotating machinery, fully utilizing the experience and technology that we have so far developed. This paper indroduces this machinery diagnostic system which was installed at the Tsuruga Nuclear Power Plant of Japan Atomic Power Company. (author)

  16. Development test procedure for the ground demonstration system rotating seals

    International Nuclear Information System (INIS)

    This test procedure provides a detailed description of the verification methods which shall be used in the development program to be conducted on the Dynamic Isotope Power System (DIPS) rotating seals of the Combined Rotating Unit (CRU) assembly to fulfill the requirements of the Ground Demonstration System design criteria. The test ojectives are to characterize seal performance so that data can be used for seal configuration selection and system performance evaluation during Ground Demonstration System (GDS) testing. The various configurations that will be tested and their test parameters are shown

  17. Visual Servoed Three-Dimensional Cell Rotation System.

    Science.gov (United States)

    Wang, Zenan; Latt, Win Tun; Tan, Steven Yih Min; Ang, Wei Tech

    2015-10-01

    Three-dimensional (3-D) positioning and orientation of embryos/oocytes is necessary to facilitate micromanipulation tasks such as cell injection and cellular structural biopsy commonly performed under a microscope. Conventional cell orientation is performed manually by using a vacuum equipped micropipette to aspirate and release the cell, which is a trial-and-error approach. The conventional method relies heavily on the skill of the operator; it also suffers from low precision, low success rate and low controllability. These drawbacks illustrate the need for a systematic 3-D cell rotational system to automate the cell orientation process. In this paper, we present a noninvasive single cell rotation system that can automatically orientate a zebrafish embryo to a desired position when both the cytoplasm and the yolk are in the focal plane. A three-point-contact model for cell rotation that involves a custom-designed rotational stage is introduced to provide precise rotational position control. A vision recognition algorithm is also proposed to enable the visual servoing function of the system. Experimental results show that the proposed system can achieve high success rates of 92.5% (x-axis rotation with 40 trails) and 97.5% (about the z-axis with 80 trails). The system can also successfully complete 3-D cell orientation at an average speed of 31 s/cell with a high in-plane rotation accuracy of 0.3 (°) . As a high precise, high controllable and deterministic cell manipulating system, it provides a starting point for automated cell manipulation for intracytoplasmic sperm injection and embryo biopsy for preimplantation genetic diagnosis. PMID:25993702

  18. Can the 13C natural abundance technique be applied to quantify the soil organic matter in crop rotations with mixed C3 and C4 plants?

    International Nuclear Information System (INIS)

    In this study, the 13C natural abundance technique was used to quantify the sources of soil C in a mixed C3 and C4 system containing corn (C4) and forages (alfalfa and bromegrass, C3). Corn-derived C in soil was estimated using a mixing model as previously. The quantity of forage-derived C in soil was estimated using two independent methods for comparison, with assumptions that there is no differential decomposition and stabilization of soil C under monoculture compared to rotations. The subtraction method yielded higher values for forage-derived C than the mixing-model method, which is based on isotopic signatures. The observed differences in forage-derived C estimates may be largely due to spatial variability of soil C at the study site. Further research with proper field layout and crop selection is required to select and refine the best approach. This study shows the potential for using the ?13C technique in mixed C3-C4 systems to quantify contributing C inputs to soil. (author)

  19. Fiber-optic rotational seismic system for investigation of the rotational events

    Science.gov (United States)

    Jaroszewicz, Leszek R.; Krajewski, Zbigniew; Kowalski, Jerzy; Zinówko, Pawe?

    2011-05-01

    The paper presents a new telemetric system for direct measurement and investigation the rotational components exist in seismic events. The FORS - fiber optic rotational seismometer and seismographs constructed on the base of the Sagnac interferometer are the elements of the system. The special construction of the system protects their elements remote control in real time via internet utilize the GSP/GSM connections. The first results according application autonomous FORS (AFORS) with accuracy in the range 4.9.10-9 - 6.1.10-8 rad/s in detection bandpass 1.66 - 212.30 Hz located in Ksi?z and Warsaw, as well as older one FORS-II (mounted in Ojców) are reported.

  20. Long-term effects of cropping systems and fertilization on crop production, soil characteristics and nitrogen cycling in the Guinean and Sudanian savannah zones of Burkina Faso (West Africa)

    International Nuclear Information System (INIS)

    The long-term effects of annual fallow and two grain legumes, namely groundnut (Arachis hypogea) and cowpea (Vigna unguiculata) on soil N, fertilizer N recovery and yield of subsequent non-fixing crops were investigated in two ecological savannah zones of West Africa. The effects of fallow and groundnut on sorghum (Sorghum bicolour) and cotton (Gossypium sp) were studied using a 10-year (1993-2003) field experiment at the agronomic research station of Farako-Ba (4 deg. 20' West, 11 deg. 6' North and 405 m altitude) in Guinean savannah zone Burkina Faso. A factorial 3x8 design in a split plot arrangement was used. Three crop rotations (cotton-groundnut-Sorghum, fallow-sorghum and mono cropping of sorghum) were used as first factor and 8 fertilizer treatments (mineral NPK fertilizer, NPK+crop residues, NPK+dolomite, PK+crop residues, PK+manure, PK+compost, PK and control) were applied as second factor. In the Sudanian savannah zone, a 5-year (1995-1999) field experiment was laid down at the research station of Kouare (11 deg 59' North, 0 deg. 19' West and 850 m altitude). A factorial of three cropping systems (cowpea-sorghum, fallow-sorghum and mono cropping of sorghum) as a first factor and 4 fertilizer treatments (mineral NPK fertilizer, NPK+dolomite, PK+manure and a control) as a second factor in a split plot design was used. In the Guinean savannah zone, grain yields of succeeding sorghum increased from 547 kg ha-1 in continuous sorghum to 912 and 1021 kg ha-1 in fallow-sorghum and cotton-groundnut-sorghum rotations respectively. Soils of fallow-sorghum and cotton-groundnut-sorghum rotations contained more mineral N at sowing. The N fertilizer use efficiency increased from 19% for the continuous sorghum to 32 and 51% for the fallow-sorghum and cotton-groundnut-sorghum respectively. Soil organic carbon increased from 0.36% in continuous sorghum to 0.39 and 0.54% in cotton-groundnut-sorghum and fallow-sorghum rotations respectively. Compared to the original soil, continuous sorghum and cotton-groundnut-sorghum rotations decreased soil organic carbon. Only fallow-sorghum rotation maintained soil organic carbon, exchange acidity and base saturation at same levels like those of original soil. Manure applications increased soil organic carbon, total N and available P. Except for the fallow-sorghum rotation, other rotations increased aluminum saturation and decreased soil pH compared to original soil. Manure or dolomite applications decreased exchange acidity and maintained soil pH and base saturation at same levels like those of original soil. Cotton-groundnut-sorghum rotation was the most efficient for the Guinea savannah zone. In this cropping system, mineral NPK fertilizer plus one t ha-1 of dolomite can be recommended for cotton and sorghum. Alternatively mineral PK fertilizer combined with 3 t ha-1 cattle manure can be applied to sorghum. Only mineral NPK fertilizer can be used on groundnut. In the Sudanian savannah zone, sorghum grain yields increased by 75 and 100% when sorghum was rotated with fallow or cowpea respectively, compared to mono cropping of sorghum. Soils of fallow-sorghum and cowpea-sorghum rotations supplied 17 and 90% more N to succeeding sorghum compared to the mono cropping system of sorghum. The N fertilizer use efficiency increased from 17% for the continuous sorghum to 22 and 26% for the cowpea-sorghum and fallow-sorghum rotations respectively. Compared to the original soil, all cropping systems decreased soil organic carbon and increased aluminum saturation. All cropping systems decreased soil pH and increased aluminum saturation compared to original soil. Cowpea-sorghum rotation was the most efficient cropping system in the Sudanian zone. In this cropping system, mineral NPK fertilizer associated with one t ha-1 of dolomite or 3 t ha-1 of manure must be applied to sorghum. But only recommended mineral NPK fertilizer can be applied for cowpea. (author)

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

    Directory of Open Access Journals (Sweden)

    Betty Mulianga

    2015-10-01

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

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

    OpenAIRE

    Betty Mulianga; Agnès Bégué; Pascal Clouvel; Pierre Todoroff

    2015-01-01

    Over the recent past, there has been a growing concern on the need for mapping cropping practices in order to improve decision-making in the agricultural sector. We developed an original method for mapping cropping practices: crop type and harvest mode, in a sugarcane landscape of western Kenya using remote sensing data. At local scale, a temporal series of 15-m resolution Landsat 8 images was obtained for Kibos sugar management zone over 20 dates (April 2013 to March 2014) to characterize c...

  3. A system of standard stars for rotational velocity determinations

    International Nuclear Information System (INIS)

    Profiles for the He I lambda 4471, Mg II lambda 4481, and Fe I lambda 4476 lines were measured in the spectra of 217 bright northern and southern stars of types 09-F9, using photoelectric scans and photographic coude spectrograms obtained at the Cerro Tololo Inter-American Observatory, Kitt Peak National Observatory, and Lowell Observatory. Half-intensity widths of the observed line profiles were compared with the corresponding quantities in a set of theoretical rotationally-broadened line profiles computed using the model-atmosphere approach. The resulting v sin i's are used to establish a system of standard rotational velocity stars, for use in estimating v sin i directly from visual inspection of spectrograms. An atlas of rotationally broadened spectra is presented, showing the effects of rotation on spectra of representative B-, A-, and F-type stars

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

    DEFF Research Database (Denmark)

    SØrensen, Ole SØe

    2012-01-01

    Quantum systems of ultra-cold particles constitute a unique tool for studying the fundamental phenomena of physics in their purest and most isolated forms. Complicated dynamics are found even for few particles and to comprehend the features of systems with many particles, we must first understand these basic building blocks. In this dissertation we investigate few-particle behavior in rotating traps and optical lattices. These systems are both experimentally realizable and are used on a daily basis in quantum gas laboratories all over the world. At temperatures near absolute zero the quantum mechanical nature of particles dominate, resulting in a behavior fundamentally different from that of classical particles. In rotating systems this causes quantization of angular momentum which can lead to macroscopic vortices in rotating Bose-Einstein condensates. In optical lattices the atom becomes extended over several lattice points causing complicated many-body dynamics and phase transitions.

  5. Patient QA systems for rotational radiation therapy

    DEFF Research Database (Denmark)

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

    2013-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Tercilio Turini

    2015-07-01

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

  7. Coupling land surface and crop growth models for predicting evapotranspiration and carbon exchange in wheat-maize rotation croplands

    Science.gov (United States)

    Lei, H.; Yang, D.; Lokupitiya, E.; Shen, Y.

    2010-10-01

    The North China Plain is one of the key crop-producing regions in China. However, water resources in the area are limited. Accurate modeling of water consumption and crop production in response to the changing environment is important. To describe the two-way interactions among climate, irrigation, and crop growth better, the modified crop phenology and physiology scheme from the SiBcrop model was coupled with the second version of the Simple Biosphere model (SiB2) to simulate crop phenology, crop production, and evapotranspiration of winter wheat and summer maize, which are two of the main crops in the region. In the coupled model, the leaf area index (LAI) produced by the crop phenology and physiology scheme was used in estimating sub-hourly energy and carbon fluxes. Observations obtained from two typical eddy covariance sites located in this region were used to validate the model. The coupled model was able to accurately simulate carbon and energy fluxes, soil water content, biomass carbon, and crop yield, especially for latent heat flux and carbon flux. The LAI was also well simulated by the model. Therefore, the coupled model is capable of assessing the responses of water resources and crop production to the changes of future climate and irrigation schedules of this region.

  8. The Influence of Habitat Manipulations on Beneficial Ground-Dwelling Arthropods in a Southeast US Organic Cropping System.

    Science.gov (United States)

    Fox, Aaron F; Orr, David B; Cardoza, Yasmin J

    2015-02-01

    Habitat manipulations, intentional provisioning of natural vegetation along crop edges, have been shown to enhance beneficial epigaeic invertebrate activity in many agricultural settings, but little research has been conducted on this practice in the southeast United States. We conducted a field-scale study to determine if habitat manipulations along the field edges of an organic crop rotation increase the activity-density of beneficial ground-dwelling invertebrates. Pitfall traps were used to collect micro and macro ground-dwelling organisms in nine organic crop fields (three each of maize, soybeans, and hay; 2.5-4.0 ha each) surrounded by four experimental habitat manipulations (planted native grass and prairie flowers, planted prairie flowers only, fallow vegetation, or mowed vegetation) during 2009 and 2010 in eastern North Carolina. Beneficial macro and micro invertebrates collected in these pitfall traps consisted primarily of Carabidae, Araneae, Collembola, and mite species. Results show that habitat manipulations had little effect on the activity-density of the dominant epigaeic invertebrates in our study system. Our results suggest that the activity-density of these organisms were instead determined by a combination of in-field characteristics, such as crop type, weed management practices, and within-field resources, along with the diversity of crop type in neighboring fields and the availability of other resources in the area. PMID:26308813

  9. Specimen rotation system of the WSU TRIGA-fueled reactor

    International Nuclear Information System (INIS)

    The specimen rotation system presently in use at the WSU reactor has been designed to provide maximum utilization of the irradiation capabilities achieved through use of TRIGA-type fuel. This paper describes the system with particular emphasis on characteristics which are advantageous to experimenters. (author)

  10. Combined Solar system and rotation curve constraints on MOND

    Science.gov (United States)

    Hees, Aurélien; Famaey, Benoit; Angus, Garry W.; Gentile, Gianfranco

    2016-01-01

    The Modified Newtonian Dynamics (MOND) paradigm generically predicts that the external gravitational field in which a system is embedded can produce effects on its internal dynamics. In this communication, we first show that this external field effect (EFE) can significantly improve some galactic rotation curves fits by decreasing the predicted velocities of the external part of the rotation curves. In modified gravity versions of MOND, this EFE also appears in the Solar system and leads to a very good way to constrain the transition function of the theory. A combined analysis of the galactic rotation curves and Solar system constraints (provided by the Cassini spacecraft) rules out several classes of popular MOND transition functions, but leaves others viable. Moreover, we show that Laser Interferometer Space Antenna Pathfinder will not be able to improve the current constraints on these still viable transition functions.

  11. Combined Solar System and rotation curve constraints on MOND

    CERN Document Server

    Hees, A; Angus, G W; Gentile, G

    2015-01-01

    The Modified Newtonian Dynamics (MOND) paradigm generically predicts that the external gravitational field in which a system is embedded can produce effects on its internal dynamics. In this communication, we first show that this External Field Effect can significantly improve some galactic rotation curves fits by decreasing the predicted velocities of the external part of the rotation curves. In modified gravity versions of MOND, this External Field Effect also appears in the Solar System and leads to a very good way to constrain the transition function of the theory. A combined analysis of the galactic rotation curves and Solar System constraints (provided by the Cassini spacecraft) rules out several classes of popular MOND transition functions, but leaves others viable. Moreover, we show that LISA Pathfinder will not be able to improve the current constraints on these still viable transition functions.

  12. Polar rotation angle identifies elliptic islands in unsteady dynamical systems

    Science.gov (United States)

    Farazmand, Mohammad; Haller, George

    2016-02-01

    We propose rotation inferred from the polar decomposition of the flow gradient as a diagnostic for elliptic (or vortex-type) invariant regions in non-autonomous dynamical systems. We consider here two- and three-dimensional systems, in which polar rotation can be characterized by a single angle. For this polar rotation angle (PRA), we derive explicit formulas using the singular values and vectors of the flow gradient. We find that closed level sets of the PRA reveal elliptic islands in great detail, and singular level sets of the PRA uncover centers of such islands. Both features turn out to be objective (frame-invariant) for two-dimensional systems. We illustrate the diagnostic power of PRA for elliptic structures on several examples.

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

    Science.gov (United States)

    Andújar, Dionisio; Weis, Martin; Gerhards, Roland

    2012-01-01

    Site-specific weed management requires sensing of the actual weed infestation levels in agricultural fields to adapt the management accordingly. However, sophisticated sensor systems are not yet in wider practical use, since they are not easily available for the farmers and their handling as well as the management practice requires additional efforts. A new sensor-based weed detection method is presented in this paper and its applicability to cereal crops is evaluated. An ultrasonic distance sensor for the determination of plant heights was used for weed detection. It was hypothesised that the weed infested zones have a higher amount of biomass than non-infested areas and that this can be determined by plant height measurements. Ultrasonic distance measurements were taken in a winter wheat field infested by grass weeds and broad-leaved weeds. A total of 80 and 40 circular-shaped samples of different weed densities and compositions were assessed at two different dates. The sensor was pointed directly to the ground for height determination. In the following, weeds were counted and then removed from the sample locations. Grass weeds and broad-leaved weeds were separately removed. Differences between weed infested and weed-free measurements were determined. Dry-matter of weeds and crop was assessed and evaluated together with the sensor measurements. RGB images were taken prior and after weed removal to determine the coverage percentages of weeds and crop per sampling point. Image processing steps included EGI (excess green index) computation and thresholding to separate plants and background. The relationship between ultrasonic readings and the corresponding coverage of the crop and weeds were assessed using multiple regression analysis. Results revealed a height difference between infested and non-infested sample locations. Density and biomass of weeds present in the sample influenced the ultrasonic readings. The possibilities of weed group discrimination were assessed by discriminant analysis. The ultrasonic readings permitted the separation between weed infested zones and non-infested areas with up to 92.8% of success. This system will potentially reduce the cost of weed detection and offers an opportunity to its use in non-selective methods for weed control. PMID:23443401

  14. An Ultrasonic System for Weed Detection in Cereal Crops

    Directory of Open Access Journals (Sweden)

    Dionisio Andújar

    2012-12-01

    Full Text Available Site-specific weed management requires sensing of the actual weed infestation levels in agricultural fields to adapt the management accordingly. However, sophisticated sensor systems are not yet in wider practical use, since they are not easily available for the farmers and their handling as well as the management practice requires additional efforts. A new sensor-based weed detection method is presented in this paper and its applicability to cereal crops is evaluated. An ultrasonic distance sensor for the determination of plant heights was used for weed detection. It was hypothesised that the weed infested zones have a higher amount of biomass than non-infested areas and that this can be determined by plant height measurements. Ultrasonic distance measurements were taken in a winter wheat field infested by grass weeds and broad-leaved weeds. A total of 80 and 40 circular-shaped samples of different weed densities and compositions were assessed at two different dates. The sensor was pointed directly to the ground for height determination. In the following, weeds were counted and then removed from the sample locations. Grass weeds and broad-leaved weeds were separately removed. Differences between weed infested and weed-free measurements were determined. Dry-matter of weeds and crop was assessed and evaluated together with the sensor measurements. RGB images were taken prior and after weed removal to determine the coverage percentages of weeds and crop per sampling point. Image processing steps included EGI (excess green index computation and thresholding to separate plants and background. The relationship between ultrasonic readings and the corresponding coverage of the crop and weeds were assessed using multiple regression analysis. Results revealed a height difference between infested and non-infested sample locations. Density and biomass of weeds present in the sample influenced the ultrasonic readings. The possibilities of weed group discrimination were assessed by discriminant analysis. The ultrasonic readings permitted the separation between weed infested zones and non-infested areas with up to 92.8% of success. This system will potentially reduce the cost of weed detection and offers an opportunity to its use in non-selective methods for weed control.

  15. A rotating liquid helium transfer system

    International Nuclear Information System (INIS)

    This chapter demonstrates the successful operation of a stable transfer system suitable for fault worthy superconducting generators. A turbine type flowmeter for liquid helium has been developed and successfully operated. The transfer system was cooled to helium temperature and the transfer of liquid was initiated without any detectable pressure oscillations or surges. Transfer system losses were computed for subcooled, two-phase and superheated helium transfer and various mass flow rates up to 70 L/h. Transfer losses are shown to be a strong function of angular velocity, void fraction and mass flow rate. It is suggested that to minimize losses and oscillation a vapor separator should be used at the transfer system inlet to control void fraction in the transfer stream

  16. 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

    Scientific Electronic Library Online (English)

    Andréia Patrícia, Andrade; Álvaro Luiz, Mafra; Cristiano Della, Picolla; Jackson Adriano, Albuquerque; Ildegardis, Bertol.

    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. Abstract in english 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 t [...] illage (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, total nitrogen (TN) and water pH. The no-tillage system increased TOC and nutrient levels in comparison with conventional tillage, especially in the surface soil layer. Maize and vetch crop succession had higher TOC and TN contents in the surface soil layer compared to crop rotation under no-tillage.

  17. Wireless computer vision system for crop stress detection

    Science.gov (United States)

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

  18. Crop systems and plant roots can modify the soil water holding capacity

    Science.gov (United States)

    Doussan, Claude; Cousin, Isabelle; Berard, Annette; Chabbi, Abad; Legendre, Laurent; Czarnes, Sonia; Toussaint, Bruce; Ruy, Stéphane

    2015-04-01

    At the interface between atmosphere and deep sub-soil, the root zone plays a major role in regulating the flow of water between major compartments: groundwater / surface / atmosphere (drainage, runoff, evapotranspiration). This role of soil as regulator/control of water fluxes, but also as a supporting medium to plant growth, is strongly dependent on the hydric properties of the soil. In turn, the plant roots growing in the soil can change its structure; both in the plow layer and in the deeper horizons and, therefore, could change the soil properties, particularly hydric properties. Such root-related alteration of soil properties can be linked to direct effect of roots such as soil perforation during growth, aggregation of soil particles or indirect effects such as the release of exudates by roots that could modify the properties of water or of soil particles. On an another hand, the rhizosphere, the zone around roots influenced by the activity of root and associated microorganisms, could have a high influence on hydric properties, particularly the water retention. To test if crops and plant roots rhizosphere may have a significant effect on water retention, we conducted various experiment from laboratory to field scales. In the lab, we tested different soil and species for rhizospheric effect on soil water retention. Variation in available water content (AWC) between bulk and rhizospheric soil varied from non-significant to a significant increase (to about 16% increase) depending on plant species and soil type. In the field, the alteration of water retention by root systems was tested in different pedological settings for a Maize crop inoculated or not with the bacteria Azospirillum spp., known to alter root structure, growth and morphology. Again, a range of variation in AWC was evidenced, with significant increase (~30%) in some soil types, but more linked to innoculated/non-innoculated plants rather than to a difference between rhizospheric and bulk soil. Finally, in field condition, on a larger time scale, we investigated the effect of crop alternations on the Lusignan ACBB SOERE site. That site presents on the same soil type different crop alternation treatments: an old, continuous grassland, a 8-year continuous cereal rotation and an alternation of cereal/grassland (3-years cereals and 3 to 6 years grassland). Measurements of AWC in these different crop systems setting, 8 years after implementation of the SOERE, show that AWC was different in the cereal/grassland alternation compared to the continuous cereal or grassland cropping systems (~15-20% increase). If such alteration of AWC may seem modest, modeling (in the case of ACBB SOERE) shows that this increase in AWC would increase the cereal yield but also decrease the water drainage out of the root zone, and the possible associated loss of nitrate and pesticides. As a conclusion, in line with some other literature data, roots can influence soil hydric properties and this opens a way to use plants as "soil engineers" to modulate the properties of the root zone, and thus the components of water balance, to mitigate effects of drought on crops… However, how and how much plants will modify the hydric properties, a question which mixes physics, biology, microbiology, crop system settings, is still in infancy and needs further research.

  19. 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; Schjønning, Per

    2010-01-01

    : total soil organic carbon (SOC), total N, microbial biomass N (MBN), potentially mineralizable N (PMN), and levels of potential ammonium oxidation (PAO) and denitrifying enzyme activity (DEA). In situ measurements of soil heterotrophic carbon dioxide (CO2) respiration and nitrous oxide emissions were...... crops, respectively. Nevertheless, SOC levels in 2008 were similar across systems. The cumulative soil respiration for the period February to August 2008 ranged between 2 and 3 t CO2–C ha-1 and was correlated (r = 0.95) with average C inputs. In the organic cropping systems, pig slurry application and......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...

  20. Rotation and momentum transport in tokamaks and helical systems

    International Nuclear Information System (INIS)

    Poloidal and toroidal rotation has been recognized to play an important role in heat transport and magnetohydrodynamic (MHD) stability in tokamaks and helical systems. It is well known that the E × B shear due to poloidal and toroidal flow suppresses turbulence in the plasma and contributes to the improvement of heat and particle transport, while toroidal rotation helps one to stabilize MHD instabilities such as resistive wall modes and neoclassical tearing mode. Therefore, understanding the role of momentum transport in determining plasma rotation is crucial in toroidal discharges, both in tokamaks and helical systems. In this review paper, the driving and damping mechanisms of poloidal and toroidal rotation are outlined. Driving torque due to neutral beam injection and radio-frequency waves, and damping due to parallel viscosity and neoclassical toroidal viscosity (NTV) are described. Regarding momentum transport, the radial flux of momentum has diffusive and non-diffusive (ND) terms, and experimental investigations of these are discussed. The magnitude of the diffusive term of momentum transport is expressed as a coefficient of viscous diffusivity. The ratio of the viscous diffusivity to the thermal diffusivity (Prandtl number) is one of the interesting parameters in plasma physics. It is typically close to unity, but sometimes can deviate significantly depending on the turbulent state. The ND terms have two categories: one is the so-called momentum pinch, whose magnitude is proportional to (or at least depends on) the velocity itself, and the other is an off-diagonal term in which the magnitude is proportional to (or at least depends on) the temperature or/and pressure gradient, independent of the velocity or its gradient. The former has no sign dependence; rotation due to the momentum pinch does not depend on the sign of the rotation itself, whether it is parallel to the plasma current (co-direction) or anti-parallel to the plasma current (counter-direction). In contrast, the latter has a sign dependence; the rotation due to the off-diagonal residual term is either in the co- or counter-direction depending on the turbulence state, but not on the sign of the rotation itself. This residual term can also act as a momentum source for intrinsic rotation. The experimental results of investigations of these ND terms are described. Finally the current understanding of the mechanisms behind the ND terms in momentum transport, and predictions of intrinsic rotation driven by these terms are reviewed. (review article)

  1. Rotation and momentum transport in tokamaks and helical systems

    Science.gov (United States)

    Ida, K.; Rice, J. E.

    2014-04-01

    Poloidal and toroidal rotation has been recognized to play an important role in heat transport and magnetohydrodynamic (MHD) stability in tokamaks and helical systems. It is well known that the E × B shear due to poloidal and toroidal flow suppresses turbulence in the plasma and contributes to the improvement of heat and particle transport, while toroidal rotation helps one to stabilize MHD instabilities such as resistive wall modes and neoclassical tearing mode. Therefore, understanding the role of momentum transport in determining plasma rotation is crucial in toroidal discharges, both in tokamaks and helical systems. In this review paper, the driving and damping mechanisms of poloidal and toroidal rotation are outlined. Driving torque due to neutral beam injection and radio-frequency waves, and damping due to parallel viscosity and neoclassical toroidal viscosity (NTV) are described. Regarding momentum transport, the radial flux of momentum has diffusive and non-diffusive (ND) terms, and experimental investigations of these are discussed. The magnitude of the diffusive term of momentum transport is expressed as a coefficient of viscous diffusivity. The ratio of the viscous diffusivity to the thermal diffusivity (Prandtl number) is one of the interesting parameters in plasma physics. It is typically close to unity, but sometimes can deviate significantly depending on the turbulent state. The ND terms have two categories: one is the so-called momentum pinch, whose magnitude is proportional to (or at least depends on) the velocity itself, and the other is an off-diagonal term in which the magnitude is proportional to (or at least depends on) the temperature or/and pressure gradient, independent of the velocity or its gradient. The former has no sign dependence; rotation due to the momentum pinch does not depend on the sign of the rotation itself, whether it is parallel to the plasma current (co-direction) or anti-parallel to the plasma current (counter-direction). In contrast, the latter has a sign dependence; the rotation due to the off-diagonal residual term is either in the co- or counter-direction depending on the turbulence state, but not on the sign of the rotation itself. This residual term can also act as a momentum source for intrinsic rotation. The experimental results of investigations of these ND terms are described. Finally the current understanding of the mechanisms behind the ND terms in momentum transport, and predictions of intrinsic rotation driven by these terms are reviewed.

  2. Fibre Optic System for Monitoring Rotational Seismic Phenomena

    Directory of Open Access Journals (Sweden)

    Anna Kurzych

    2014-03-01

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

  3. 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

    OpenAIRE

    Pablo Undurraga D; Erick Zagal V; Gloria Sepúlveda W; Natalia Valderrama V

    2009-01-01

    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 soi...

  4. Characteristics of Soil in Environment Friendly Rice-wheat Cropping System in Southern Korea

    Directory of Open Access Journals (Sweden)

    Y.S. Cho

    2002-01-01

    Full Text Available A field experiment was conducted to compare soil microbial populations, microbial-N status and soil physical and chemical characteristics in a no-till, unfertilized, direct-sown, wheat-rice, relay-cropping system (NTWR and also in a conventional transplanted rice single cropping system (CTR. The wheat-rice system was imposed for 2, 4 and 7 years to identify the time course responses in the soil and crop. Recycling of crop residues in the wheat-rice cropping system generally increased the soil organic matter (OM contents but reduced the level of available P2O5 compared with the conventional system. Generally the soil was fertile with a high initial organic matter contents. Organic matter was increased by 30% during the 7 years of wheat-rice cropping. Other soil physical features, bulk density and permeability to air and water indicated that soil structure could be improved in response to wheat-rice cropping. Seasonal variability of soil microorganisms suggested that 7-year cropping could improve soil physicochemical characteristics but mineral contents in relation to cation exchange capacity (CEC would decrease after 4-years cropping. Soil tillage may adversely affect soil microbial dynamics. In conclusion, a no-till, unfertilized, direct-sown, wheat-rice cropping system, is likely to sustain grain yield by improving soil bio-physicochemical factors and is one of the most ecologically stable, economically sound and socially supportive wheat-rice production systems.

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

    International Nuclear Information System (INIS)

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-01-01

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

  7. Rotation Invariant Content-Based Image Retrieval System

    Directory of Open Access Journals (Sweden)

    P. Vijaya Bharati

    2014-11-01

    Full Text Available The emergence of multimedia technology and the rapid growth in the number and type of multimedia assets controlled by several entities, yet because the increasing range of image and video documents showing on the Internet, have attracted vital analysis efforts in providing tools for effective retrieval and management of visual data. So the need for image retrieval system arose. Out of many existing systemsROTATION INVARIANT CONTENT-BASED IMAGE RETRIEVAL SYSTEM” is the most efficient and accurate one. Effective texture feature is an essential component in any CBIR system. In the past, spectral features like Gabor and Wavelet have shown superior retrieval performance than most statistical and structural options. Recent researches on multi-resolution analysis have found that curvelet captures texture properties like curves, lines and edges with additional accuracy than Gabor filters. However, the texture feature extracted using curvelet transform is not rotation invariant. This can degrade its retrieval performance considerably, particularly in cases where there are many similar images with different orientations. We analyses the curvelet transform and derives a useful approach to extract rotation invariant curvelet features. The new system which uses curvelet transform for extracting texture features includes rotation invariant.

  8. 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

    Scientific Electronic Library Online (English)

    Edmilson José, Ambrosano; Rozario, Azcón; Heitor, Cantarella; Gláucia Maria Bovi, Ambrosano; Eliana Aparecida, Schammass; Takashi, Muraoka; Paulo César Ocheuze, Trivelin; Fabrício, Rossi; Nivaldo, Guirado; Maria Regina Gonçalves, Ungaro; Juliana Rolim Salomé, Teramoto.

    2010-12-01

    Full Text Available 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 objecti [...] ve 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-Caiapó, 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. Abstract in english 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.

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

    Directory of Open Access Journals (Sweden)

    Colbach Nathalie

    2004-01-01

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

  10. Rotation Invariant Content-Based Image Retrieval System

    OpenAIRE

    P. Vijaya Bharati; A.Rama Krishna

    2014-01-01

    The emergence of multimedia technology and the rapid growth in the number and type of multimedia assets controlled by several entities, yet because the increasing range of image and video documents showing on the Internet, have attracted vital analysis efforts in providing tools for effective retrieval and management of visual data. So the need for image retrieval system arose. Out of many existing systemsROTATION INVARIANT CONTENT-BASED IMAGE RETRIEVAL SYSTEM” is the most efficient and acc...

  11. Automatic expert system based on images for accuracy crop row detection in maize fields

    OpenAIRE

    Guerrero, J. M.; Guijarro, M.; Montalvo, M.; Romeo, J.; Emmi, L.; A. Ribeiro; Pajares, G.

    2013-01-01

    This paper proposes an automatic expert system for accuracy crop row detection in maize fields based on images acquired from a vision system. Different applications in maize, particularly those based on site specific treatments, require the identification of the crop rows. The vision system is designed with a defined geometry and installed onboard a mobile agricultural vehicle, i.e. submitted to vibrations, gyros or uncontrolled movements. Crop rows can be estimated by applying geometrical pa...

  12. Magnetic suspension of a rotating system. Application to inertial flywheels

    International Nuclear Information System (INIS)

    The various possible magnetic suspension configurations compatible with rotating mechanical systems are defined from studies of the characteristics of different types of magnetic bearings. The results obtained are used in the design and realization of a magnetic suspension for an inertial flywheel. (author)

  13. New portable sensor system for rotation seismic motion measurements.

    Czech Academy of Sciences Publication Activity Database

    Brokešová, J.; Málek, Ji?í

    2010-01-01

    Ro?. 81, ?. 8 (2010), 084501. ISSN 0034-6748 R&D Projects: GA ?R GAP210/10/0925 Institutional research plan: CEZ:AV0Z30460519 Keywords : rotational seismology * sensor system Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 1.598, year: 2010

  14. 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.

  15. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-05-01

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

  17. The earth dynamic system: the earth rotation vs mantle convection

    OpenAIRE

    Shuping Chen

    2010-01-01

    The earth dynamic system is one of the key scientific questions on the earth science. The thermodynamic behavior and gravity force of the earth and the rheology nature of the mantle prove that mantle convection is the main power source leading the lithosphere to break and move. Yet the directivity of both the structures in the crust and plate movement reminds of the earth rotation. Here we demonstrate that the mantle convection and inertia force of the earth rotation affect each other, the fo...

  18. Simplified aerodynamic analysis of the cyclogiro rotating wing system

    Science.gov (United States)

    Wheatley, John B

    1930-01-01

    A simplified aerodynamic theory of the cyclogiro rotating wing is presented herein. In addition, examples have been calculated showing the effect on the rotor characteristics of varying the design parameters of the rotor. A performance prediction, on the basis of the theory here developed, is appended, showing the performance to be expected of a machine employing this system of sustentation. The aerodynamic principles of the cyclogiro are sound; hovering flight, vertical climb, and a reasonable forward speed may be obtained with a normal expenditure of power. Auto rotation in a gliding descent is available in the event of a power-plant failure.

  19. Influência da rotação de culturas na infestação e danos causados por Sternechus Subsignatus (Boheman) (Coleoptera: Curculionidae) em plantio direto / Influence of crop rotation on Sternechus Subsignatus (Boheman) (Coleoptera: Curculionidae) infestation and damage under no-tillage

    Scientific Electronic Library Online (English)

    Mauro Tadeu Braga da, Silva.

    1996-04-01

    Full Text Available Avaliou-se, a campo, a influência da rotação de culturas com milho e soja na infestação e nos danos causados pelo tamanduâ-da-soja, Sternechus subsignatus (Boheman, 1836), em solos manejados no sistema de plantio direto. no município de Cruz Alta, RS. Os resultados indicaram que a infestação de adul [...] tos, larvas olivas e larvas hibernantes e os danos de percentagem de plantas de soja atacadas e mortas foram significativamente inferiores na rotação com milho e soja do que o verificado no monocultivo de soja. A soja em rotação com o milho produziu significativamente mais grãos do que a soja em monocultivo. Concluiu-se que a rotação com milho e soja constitui-se numa prática importante a ser usada no manejo de S. subsignatus em áreas infestadas, pelo fato do inseto não se alimentar e nem ovipositar nas plantas de milho, o que propicia a diminuição da sua população. Abstract in english The corn and soybean crop rotation on Sternechus subsignatus (Boheman. 1836) infestation and damage under notillage was evaluated in the field in the county of Cruz Alta, Rio Grande do Sul State. Brazil. The results indicated that adult infestation. active larvae and hibernating larvae, and that the [...] percent damage of soybean plants attacked and dead, were significantiy lower in the corn-soybean crop rotation in relation to soybean under monocultural system. Soybean in rotation with corn showes significant more grain productivity than soybean under monocultural system. It was concluded that the corn-soybean rotation is an important tool for the management of S. subsignatus in infested areas due to the fact that the insect neither feed nor perform oviposition on corn plants, thus reducing its population.

  20. Influência da rotação de culturas na infestação e danos causados por Sternechus Subsignatus (Boheman (Coleoptera: Curculionidae em plantio direto Influence of crop rotation on Sternechus Subsignatus (Boheman (Coleoptera: Curculionidae infestation and damage under no-tillage

    Directory of Open Access Journals (Sweden)

    Mauro Tadeu Braga da Silva

    1996-04-01

    Full Text Available Avaliou-se, a campo, a influência da rotação de culturas com milho e soja na infestação e nos danos causados pelo tamanduâ-da-soja, Sternechus subsignatus (Boheman, 1836, em solos manejados no sistema de plantio direto. no município de Cruz Alta, RS. Os resultados indicaram que a infestação de adultos, larvas olivas e larvas hibernantes e os danos de percentagem de plantas de soja atacadas e mortas foram significativamente inferiores na rotação com milho e soja do que o verificado no monocultivo de soja. A soja em rotação com o milho produziu significativamente mais grãos do que a soja em monocultivo. Concluiu-se que a rotação com milho e soja constitui-se numa prática importante a ser usada no manejo de S. subsignatus em áreas infestadas, pelo fato do inseto não se alimentar e nem ovipositar nas plantas de milho, o que propicia a diminuição da sua população.The corn and soybean crop rotation on Sternechus subsignatus (Boheman. 1836 infestation and damage under notillage was evaluated in the field in the county of Cruz Alta, Rio Grande do Sul State. Brazil. The results indicated that adult infestation. active larvae and hibernating larvae, and that the percent damage of soybean plants attacked and dead, were significantiy lower in the corn-soybean crop rotation in relation to soybean under monocultural system. Soybean in rotation with corn showes significant more grain productivity than soybean under monocultural system. It was concluded that the corn-soybean rotation is an important tool for the management of S. subsignatus in infested areas due to the fact that the insect neither feed nor perform oviposition on corn plants, thus reducing its population.

  1. Incorporation of Green Manure Plants into Bean Cropping Systems Contribute to Root-Knot Nematode Suppression

    OpenAIRE

    J. W. Kimenju; A.M. Kagundu; J. H. Nderitu; F. Mambala; G.K. Mutua; G. M. Kariuki

    2008-01-01

    Green manure plants were evaluated to determine their suitability as rotation crops with common bean to suppress root-knot (Meloidogyne spp.) nematodes. They were also evaluated as soil amendments in nematode control. The plants were Calliandra calothyrsus, Canavalia ensiformis, Chenopodium quinoa, Crotalaria juncea, Desmodium uncinatum, Gliricidia sepium, Leucaena leucocephala, Mucuna pruriens, Tephrosia purpurea, Tithonia diversifolia, Vicia villosa, Sesbania sesban and Tagetes minut...

  2. Rotational angular momenta of close binary system components

    International Nuclear Information System (INIS)

    The ratio between rotational angular momentum, Jsub(rot), and orbital angular momentum, Jsub(orb), in close binary systems and its variation with mass ratio is studied. The tables and the graphs give this variation for detached systems, contact systems, semidetached systems and for systems containing a supernovae-remnant component and a containing a supernovae-remnant component and a contact component. For this study some statistical relations of close binary stars were used. The ratio Jsub(rot)/Jsub(orb) is sensitive to the variation of the mass ratio q. If q differs much from unity and if the concentration of the stellar matter is moderate (polytropic index n approximately 3), the neglect of rotational angular momentum, Jsub(rot), is not justified. (Auth.)

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

    DEFF Research Database (Denmark)

    Doltra, J; Olesen, JØrgen E

    2015-01-01

    Mitigation of greenhouse gas emissions from agriculture should be assessed across cropping systems and agroclimatic regions. In this study, we investigate the ability of the FASSET model to analyze differences in the magnitude of N2O emissions due to soil, climate and management factors in cereal-based cropping systems. Forage maize was grown in a conventional dairy system at Mabegondo (NW Spain) and wheat and barley in organic and conventional crop rotations at Foulum (NW Denmark). These two European sites represent agricultural areas with high and low to moderate emission levels, respectively. Field trials included plots with and without catch crops that were fertilized with either mineral N fertilizer, cattle slurry, pig slurry or digested manure. Non-fertilized treatments were also included. Measurements of N2O fluxes during the growing cycle of all the crops at both sites were performed with the static chamber method with more frequent measurements post-fertilization and biweekly measurements when high fluxes were not expected. All cropping systems were simulated with the FASSET version 2.5 simulation model. Cumulative soil seasonal N2O emissions were about ten-fold higher at Mabegondo than at Foulum when averaged across systems and treatments (8.99 and 0.71 kg N2O-N ha?1, respectively). The average simulated cumulative soil N2O emissions were 9.03 and 1.71 kg N2O-N ha?1 at Mabegondo and at Foulum, respectively. Fertilization, catch crops and cropping systems had lower influence on the seasonal soil N2O fluxes than the environmental factors. Overall, in its current version FASSET reproduced the effects of the different factors investigated on the cumulative seasonal soil N2O emissions but temporally it overestimated emissions from nitrification and denitrification on particular days when soil operations, ploughing or fertilization, took place. The errors associated with simulated daily soil N2O fluxes increased with the magnitude of the emissions. For resolving causes of differences in simulated and measuredfluxes more intensive and temporally detailed measurements of N2O fluxes and soil C and N dynamics would be needed.

  4. Relationships among bulk soil physicochemical, biochemical, and microbiological parameters in an organic alfalfa-rice rotation system.

    Science.gov (United States)

    Lopes, Ana R; Bello, Diana; Prieto-Fernández, Ángeles; Trasar-Cepeda, Carmen; Manaia, Célia M; Nunes, Olga C

    2015-08-01

    The microbial communities of bulk soil of rice paddy fields under an ancient organic agriculture regimen, consisting on an alfalfa-rice rotation system, were characterized. The drained soil of two adjacent paddies at different stages of the rotation was compared before rice seeding and after harvesting. The relationships among the soil microbial, physicochemical, and biochemical parameters were investigated using multivariate analyses. In the first year of rice cropping, aerobic cultivable heterotrophic populations correlated with lineages of presumably aerobic bacteria (e.g., Sphingobacteriales, Sphingomonadales). In the second year of rice cropping, the total C content correlated with presumable anaerobic bacteria (e.g., Anaerolineae). Independently of the year of rice cropping, before rice seeding, proteolytic activity correlated positively with the cultivable aerobic heterotrophic and ammonifier populations, the soil catabolic profile and with presumable aerobes (e.g., Sphingobacteriales, Rhizobiales) and anaerobes (e.g., Bacteroidales, Anaerolineae). After harvesting, strongest correlations were observed between cultivable diazotrophic populations and bacterial groups described as comprising N2 fixing members (e.g., Chloroflexi-Ellin6529, Betaproteobacteria, Alphaproteobacteria). It was demonstrated that chemical parameters and microbial functions were correlated with variations on the total bacterial community composition and structure occurring during rice cropping. A better understanding of these correlations and of their implications on soil productivity may be valid contributors for sustainable agriculture practices, based on ancient processes. PMID:25850741

  5. Mixed crop-livestock systems: an economic and environmental-friendly way of farming?

    Science.gov (United States)

    Ryschawy, J; Choisis, N; Choisis, J P; Joannon, A; Gibon, A

    2012-10-01

    Intensification and specialisation of agriculture in developed countries enabled productivity to be improved but had detrimental impacts on the environment and threatened the economic viability of a huge number of farms. The combination of livestock and crops, which was very common in the past, is assumed to be a viable alternative to specialised livestock or cropping systems. Mixed crop-livestock systems can improve nutrient cycling while reducing chemical inputs and generate economies of scope at farm level. Most assumptions underlying these views are based on theoretical and experimental evidence. Very few assessments of their environmental and economic advantages have nevertheless been undertaken in real-world farming conditions. In this paper, we present a comparative assessment of the environmental and economic performances of mixed crop-livestock farms v. specialised farms among the farm population of the French 'Coteaux de Gascogne'. In this hilly region, half of the farms currently use a mixed crop-livestock system including beef cattle and cash crops, the remaining farms being specialised in either crops or cattle. Data were collected through an exhaustive survey of farms located in our study area. The economic performances of farming systems were assessed on 48 farms on the basis of (i) overall gross margin, (ii) production costs and (iii) analysis of the sensitivity of gross margins to fluctuations in the price of inputs and outputs. The environmental dimension was analysed through (i) characterisation of farmers' crop management practices, (ii) analysis of farm land use diversity and (iii) nitrogen farm-gate balance. Local mixed crop-livestock farms did not have significantly higher overall gross margins than specialised farms but were less sensitive than dairy and crop farms to fluctuations in the price of inputs and outputs considered. Mixed crop-livestock farms had lower costs than crop farms, while beef farms had the lowest costs as they are grass-based systems. Concerning crop management practices, our results revealed an intensification gradient from low to high input farming systems. Beyond some general trends, a wide range of management practices and levels of intensification were observed among farms with a similar production system. Mixed crop-livestock farms were very heterogeneous with respect to the use of inputs. Nevertheless, our study revealed a lower potential for nitrogen pollution in mixed crop-livestock and beef production systems than in dairy and crop farming systems. Even if a wide variability exists within system, mixed crop-livestock systems appear to be a way for an environmental and economical sustainable agriculture. PMID:22717157

  6. Cryogenic cooling with cryocooler on a rotating system

    CERN Document Server

    Oguri, Shugo; Kawai, Masanori; Tajima, Osamu

    2013-01-01

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

  7. Rotação e sucessão de culturas para o manejo do nematoide reniforme em área de produção de soja / Crop rotation and crop sequences for the management of the reniform nematode in area of soybean production

    Scientific Electronic Library Online (English)

    Hugo Márcio, Leandro; Guilherme Lafourcade, Asmus.

    Full Text Available O nematoide reniforme (Rotylenchulus reniformis) tem se tornado crescente problema fitossanitário da cultura da soja. Considerando a limitada disponibilidade de cultivares de soja que aliem resistência ao nematoide a outras características agronômicas desejáveis, estuda-se a possibilidade de utiliza [...] ção de manejo cultural para seu controle. Este trabalho visou avaliar o efeito da rotação de culturas no verão com milho, Crotalaria ochroleuca ou soja; e o manejo de entressafra, com Brachiaria ruziziensis como espécie de cobertura ou pousio. O experimento foi implantado em solo naturalmente infestado pelo nematoide reniforme (1245 nematoides/200cc de solo) em delineamento experimental de blocos ao acaso, com quatro repetições, em esquema fatorial 3x2 (cultivos de verão x manejo de entressafra). Foram avaliadas a densidade populacional do nematoide no solo e sua variação durante as safras e entressafras, bem como a produtividade da soja na safra subsequente à rotação de culturas. Não houve efeito do manejo da entressafra com braquiária sobre o nematoide. A rotação de culturas com milho ou crotalária no verão propiciou redução da densidade populacional do nematoide reniforme em comparação ao monocultivo de soja, com reflexos positivos sobre a produtividade de soja na safra seguinte Abstract in english The reniform nematode (Rotylenchulus reniformis) has become a growing disease problem to soybean crop. Considering the limited availability of soybean varieties that combine resistance to the nematode and other desirable agronomic traits, cultural management could be an approach for the nematode man [...] agement. This study aimed to evaluate the effect of summer season crop rotations with corn or sunnhemp compared with soybean monocropping, and fall management with ruzizigrass as a covercrop compared to fallow on the nematode population. The experiment was carried-out in a naturally infested soil (1245 reniform nematodes/200cc soil) in a randomized block design, with six treatments arranged in plots with 6x3m (18m2) with four replications in a factorial 3x2 (summer crop x fall management). The nematode soil population density and its variation during the season as well as the soybean yield in the subsequent soybean crop were evaluated. Crop rotation with corn or sunnhemp led to the decrease on the reniform nematode population density compared to the monoculture of soybeans, with positive effects on soybean yield in the following season. There was no effect of cover cropping with ruzizigrass on the reniform nematode population

  8. Rotação e sucessão de culturas para o manejo do nematoide reniforme em área de produção de soja / Crop rotation and crop sequences for the management of the reniform nematode in area of soybean production

    Scientific Electronic Library Online (English)

    Hugo Márcio, Leandro; Guilherme Lafourcade, Asmus.

    2015-06-01

    Full Text Available O nematoide reniforme (Rotylenchulus reniformis) tem se tornado crescente problema fitossanitário da cultura da soja. Considerando a limitada disponibilidade de cultivares de soja que aliem resistência ao nematoide a outras características agronômicas desejáveis, estuda-se a possibilidade de utiliza [...] ção de manejo cultural para seu controle. Este trabalho visou avaliar o efeito da rotação de culturas no verão com milho, Crotalaria ochroleuca ou soja; e o manejo de entressafra, com Brachiaria ruziziensis como espécie de cobertura ou pousio. O experimento foi implantado em solo naturalmente infestado pelo nematoide reniforme (1245 nematoides/200cc de solo) em delineamento experimental de blocos ao acaso, com quatro repetições, em esquema fatorial 3x2 (cultivos de verão x manejo de entressafra). Foram avaliadas a densidade populacional do nematoide no solo e sua variação durante as safras e entressafras, bem como a produtividade da soja na safra subsequente à rotação de culturas. Não houve efeito do manejo da entressafra com braquiária sobre o nematoide. A rotação de culturas com milho ou crotalária no verão propiciou redução da densidade populacional do nematoide reniforme em comparação ao monocultivo de soja, com reflexos positivos sobre a produtividade de soja na safra seguinte Abstract in english The reniform nematode (Rotylenchulus reniformis) has become a growing disease problem to soybean crop. Considering the limited availability of soybean varieties that combine resistance to the nematode and other desirable agronomic traits, cultural management could be an approach for the nematode man [...] agement. This study aimed to evaluate the effect of summer season crop rotations with corn or sunnhemp compared with soybean monocropping, and fall management with ruzizigrass as a covercrop compared to fallow on the nematode population. The experiment was carried-out in a naturally infested soil (1245 reniform nematodes/200cc soil) in a randomized block design, with six treatments arranged in plots with 6x3m (18m2) with four replications in a factorial 3x2 (summer crop x fall management). The nematode soil population density and its variation during the season as well as the soybean yield in the subsequent soybean crop were evaluated. Crop rotation with corn or sunnhemp led to the decrease on the reniform nematode population density compared to the monoculture of soybeans, with positive effects on soybean yield in the following season. There was no effect of cover cropping with ruzizigrass on the reniform nematode population

  9. Spatiotemporal simulation of changes in rice cropping systems in the Mekong Delta, Vietnam

    Science.gov (United States)

    Chen, Cheng-Ru; Chen, Chi-Farn; Son, Nguyen-Thanh

    2015-04-01

    With the dramatic development of agro-economics, population growth, and climate change, the rice cropping systems in the Vietnamese Mekong Delta (VMD) have been undergoing a major change. Information on rice cropping practices and changes in cropping systems is critical for policymakers to devise successful strategies to ensure food security and rice grain exports