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. Recycling of crop residues for sustainable crop production in a maize-groundnut rotation system

    International Nuclear Information System (INIS)

    A long-term field experiment, which was established to investigate the contribution of crop residues to the N-economy of a maize-groundnut rotation system, consisted of three treatments: (i) T1, the recommended rate of chemical fertilizer with residue, (ii) T2, the recommended rate of chemical fertilizer without residue, and (iii) T3, a combination of organic fertilizer (chicken manure) and chemical fertilizer with residue. In order to investigate the N contribution from residues of the first crop (maize) to subsequent crops, the maize was labelled with 15N in the T1 and T2 treatments. Fertilizer N (15N-ammonium sulphate, 9.82% a.e.) was applied (60 kg N ha-1) to microplots within each yield plot, to generate labelled maize residue. At the same time 90 kg N ha-1 unlabelled N fertilizer was applied to provide the recommended rate for maize of 150 kg Nha-1. Uptake of N and K by subsequent crops was significantly higher in crop-residue treatments, whereas uptake of P, Ca and Mg was not significantly affected. Soil pH, organic C, cation-exchange capacity, soil resistance, water content and bulk density were not significantly changed after four crop-residue applications. Soil organic matter size and density fractions seemed to increase, with application of residues, but without statistical significance. Soil available P and exchangeable K were significantly higher in plots with crop residues. Recovery of fertilizer 15Nues. Recovery of fertilizer 15N by the first crop ranged from 19 to 22%. In the following crop, the recoveries were only 5.1% and 5.6% in plants of T1 and T2 treatment and only trace recoveries of 15N occurred in the subsequent crop. Fertilizer 15N retained in the soil after harvest of the first crop was 35 to 44%, whereas after the second crop 33% was present in crop-residue treated plots and 26% in plots where crop residues had been removed. Nitrogen mineralization from maize residues was quite rapid from 4 to 8 weeks after incorporation due to the hot, humid conditions. Thus, for good synchrony of release of N from residues and uptake of N by the crop, sowing should be 4 to 6 weeks after residue incorporation. However, in a rain-fed area it is sometimes inevitable that fallow periods are long, i.e. more than 6 weeks, depending on the rainfall, as in this study. Contributions of crop residues to economic yields were not significant, even after six crop cycles. (author)

  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) %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. The response to P-Derived from phosphate rock and TSP by crops grown in a simulated crop rotation system

    International Nuclear Information System (INIS)

    The response to P-Derived from phosphate rock and TSP by crops grown in a simulated crop rotation system. A green house experiment was carried out on a simulated crop rotation system of upland rice-soybean-mungbean to determine the effect of P-derived from different phosphate rock (PR) sources and TPS using 12P. The data obtained reveal that all the P-sources has a significant effect on the growth of all the there crops, expressed in dry weight, % P-total and total P-uptake (mg P pot-1). For the P-source it was shown that % P-derived from PR/TSP and their uptake (mg P pot-1) was quite high, showing that the PRs applied were of good reactivity. The residue of the PRs has also still a good effect on plant growth than that of TSP. The efficiency of PRs was far below that of TSP. This apparently was due to the high rate of application, ten times the rate of TSP

  6. The Response to P-Derived from Phosphate Rock and TSP by Crops Grown in a Simulated Crop Rotation System

    International Nuclear Information System (INIS)

    A green house experiment was carried out on a simulated crop rotation system of upland rice-soybean-mungbean to determine the effect of P-derived from different phosphate rock (PR) sources and TSP using 32P. The data obtained reveal that all the P-sources has a significant effect on the growth of all the three crops, expressed in dry weight, % P-total and total P-uptake (mg P pot-1). For the P-source it was shown that % P-derived from PR/TSP and their uptake (mg P pot-1) was quite high, showing that the PRs applied were of good reactivity. The residue of the PRs has also still a good effect on plant growth than that of TSP. The efficiency of PRs was far below that of TSP. This apparently was due to the high rate of application, ten times the rate of TSP. (author)

  7. 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)

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

    OpenAIRE

    Bo?ena Cwalina-Abroziak; Kurowski, Tomasz P.

    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...

  9. 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

    2001-12-01

    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.

  10. 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%l 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)

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

    Science.gov (United States)

    Czaban, Janusz; Wróblewska, Barbara; Su?ek, Alicja; Mikos, Marzena; Boguszewska, Edyta; Podolska, Gra?yna; Nieróbca, Anna

    2015-06-01

    Field experiments were conducted during three consecutive growing seasons (2007/08, 2008/09 and 2009/10) with four winter wheat (Triticum aestivum L.) cultivars - 'Bogatka', 'Kris', 'Satyna' and 'Tonacja' - grown on fields with a three-field crop rotation (winter triticale, spring barley, winter wheat) and in a four-field crop rotation experiment (spring wheat, spring cereals, winter rapeseed, winter wheat). After the harvest, kernels were surface disinfected with 2% NaOCl and then analysed for the internal infection by different species of Fusarium. Fusaria were isolated on Czapek-Dox iprodione dichloran agar medium and identified on the basis of macro- and micro-morphology on potato dextrose agar and synthetic nutrient agar media. The total wheat grain infection by Fusarium depended mainly on relative humidity (RH) and a rainfall during the flowering stage. Intensive rainfall and high RH in 2009 and 2010 in the period meant the proportions of infected kernels by the fungi were much higher than those in 2008 (lack of precipitation during anthesis). Weather conditions during the post-anthesis period changed the species composition of Fusarium communities internally colonising winter wheat grain. The cultivars significantly varied in the proportion of infected kernels by Fusarium spp. The growing season and type of crop rotation had a distinct effect on species composition of Fusarium communities colonising the grain inside. A trend of a higher percentage of the colonised kernels by the fungi in the grain from the systems using more fertilisers and pesticides as well as the buried straw could be perceived. The most frequent species in the grain were F. avenaceum, F. tricinctum and F. poae in 2008, and F. avenaceum, F. graminearum, F. tricinctum and F. poae in 2009 and 2010. The contents of deoxynivalenol and zearalenon in the grain were correlated with the percentage of kernels colonised by F. graminearum and were the highest in 2009 in the grain from the four-field crop rotation. The content of T-2/HT-2 toxins was the highest in 2010 in grain from the three-field crop rotation and it was correlated with the isolation frequency of F. langsethiae. PMID:25705931

  12. 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.

  13. 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 ...

  14. 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

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

    Science.gov (United States)

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

    2015-04-01

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

  16. 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.

  17. 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.

  18. Impact of Minimum Tillage and Crop Rotation as Climate Change Adaptation Strategies on Farmer Welfare in Smallholder Farming Systems of Zambia

    Directory of Open Access Journals (Sweden)

    Elias Kuntashula

    2014-07-01

    Full Text Available Worldwide, climate change is currently recognized as one of the major challenges to increased food production. The agriculture sector is the main source of livelihoods, growth and foreign exchange earnings in many developing countries including Zambia. However, it is also a sector that is mostly vulnerable to effects of climate change. Smallholder farmers in Zambia have been adopting agricultural related adaptation strategies including minimum tillage and crop rotation to mitigate effects of climate change. There has been contentious debate on whether the two strategies (that are elements of conservation farming increase crop yields and incomes. Available literature heavily relies on biophysical experiments and show contradictions in the ability of these strategies to improve crop yields. Taking cognizance of the differences in socioeconomic circumstances of the farmers, the purpose of this study was to estimate the impact of minimum tillage and crop rotation on maize yields and incomes for farmers adopting the strategies. The study used cross sectional data collected in 2012/13 from 1231 households across six districts of Zambia and applied propensity score matching techniques and Heckman’s selection estimators to account for observed and unobserved heterogeneity between the adopters and non-adopters. The results showed that about 12 and 19% of the farmers have adopted minimum tillage and crop rotation respectively. The strategies improved on-farm maize productivity by about 26% to 38% for minimum tillage and 21% to 24% for crop rotation. Minimum tillage also improved total household maize production. On the other hand crop rotation did not significantly improve total maize production and gross income from the crop. This could reflect the small proportions of areas allocated to legumes versus the areas subsequently allocated to the maize crop during crop rotation. The impact of crop rotation on the staple maize crop could be boosted by encouraging farmers to increase the areas allocated to legumes. The legumes portfolio in the government sponsored input support programme should be increased. The results from this study generally confirm the potential direct role of agricultural related climate change adaptation strategies in improving crop productivity levels in small holder farming systems.

  19. 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.

  20. Irrigation management of crops rotations in a changing climate

    Science.gov (United States)

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

    2012-04-01

    Due to climate change we cannot continue to perform irrigation systems design and irrigation management based only on historical records of weather stations, assuming that the statistical parameters of the meteorological data remains unchanged in time, being necessary to take into account the climatic data relative to climate change scenarios. For the Mediterranean basin the various climate models indicate an increase in temperature and a reduction in precipitation and a more frequent occurrence of extreme events which will increase the risk of crop failure. Thus, it is important to adopt strategies to ensure the sustainability of irrigated agriculture in a changing climate. A very interesting technique to achieve this is the adoption of crops rotations, since they increase the heterogeneity of farming systems distributing the risk between crops and minimizing costs. This study aims to evaluate the impact of climate change in the irrigation requirements of crop rotations for the Alentejo region in the South of Portugal, and the ability of crops rotation to reduce these impacts and stabilize crops production. The IrrigRotation software was used to estimate the water requirements of two crop rotations used in the Alentejo region, Sunflower-Wheat-Barley and Sugar beet-Maize-Tomato-Wheat. IrrigRotation is a soil water balance simulation model, continuous in time, based on the dual crop coefficients methodology, which allows to compute the irrigation requirements of crop rotations. The climate data used were the observed data of the Évora and Beja weather stations (1961-90), the A2 and B2 scenarios of the HadRM3P model and the A2 scenarios of the HIRHAMh and HIRHAMhh models (2071-2100). The consideration of a set of climate change scenarios produces as a result a range of values for the irrigation requirements which can be used to define safety margins in irrigation design. The results show that for the Beja clay soils, with high values of soil water storage capacity, the crops rotations can decrease the water deficit of the rainfed crops cultivated after the irrigated crops. This is due to the storage of water in the deepest soil layers during the irrigated crops with shallow roots that increase the available soil water at the planting date of the wheat crop. For the soils with small water storage capacity and small depth, such as the Évora silt-clay-sandy soil, it was not observed the benefic effects of crops rotation in the reduction of the water deficit of the rainfed crops. The results obtained for the several climate change scenarios (2071-2100) show an increase in irrigation requirements between 13% and 70%, with the higher values corresponding to the Autumn-Winter crops (sugar beet), due to the combined effect of an increased evapotranspiration and a reduced precipitation during the crop cycle. The irrigation requirements for the peak period increased between 10% to 46%. For the climate change scenarios it was also found an increased risk of crop failure for the rainfed crops, with a water deficit value for the wheat ranging between 32% to 59%, and for the barley ranging between 34% to 45%. Keywords: Crops Rotation, Soil water balance, Irrigation, Climate change, Model

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

    Science.gov (United States)

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

    2010-05-01

    Soil erosion still remains a persistent issue in the world, and this in spite of the efforts to ameliorate soil management systems taken into account the point of view of environmental protection against soil losses. In South Brazil water erosion is mainly associated to rainfall events with a great volume and high intensity, which are more or less evenly distributed all over the year. Nowadays, direct drilling is the most widely soil management system used for the main crops of the region. However, some crops still are grown on conventionally tilled soils, which means mainly ploughing and harrowing and less frequently chisel ploughing. In Lages-Santa Catarina State, Brazil, a plot experiment under natural rain was started in 1992 on an Inceptisol with the aim of quantifying soil and water losses. Treatments included bare and vegetated plots. The crop succession was: oats (Avena strigosa), soybean (Glycine max), vetch (Vicia sativa), maize (Zea mays), fodder radish (Raphanus sativus) and beans (Phaseolus vulgaris). Soil tillage systems investigated in this study were: i) conventional tillage (CT), ii) reduced tillage (MT), iii) no tillage (NT) under crop rotation and iv) conventional tillage on bare soil (BS). Treatments CT and BS involved ploughing plus twice harrowing, whereas MT involved chisel ploughing plus harrowing. Rainfall erosivity from January 1 1992 to December 31 2009 was calculated. Soil losses from the BS treatment along the 17 year study period were higher than 1200 Mg ha-1. Crop cover significantly reduced erosion, so that under some crops soil losses in the CT treatment were 80% lower than in the BS treatment. In turn soil losses in the MT treatment, where tillage was performed by chiselling and harrowing, were on average about 50% lower than in the CT treatment. No tillage was the most efficient soil management system in reducing soil erosion, so that soil losses in the NT treatment were about 98% lower than in the BS treatment. The three vegetated treatments, CT, MT and NT showed a lower efficiency in reducing water losses than soil losses. Water losses by runoff during a number of events were of the same order of magnitude for all the management systems studied here; which was mainly true when the volume of rainfall was high and the lag between successive events was small. In general, soil losses in the autumn-winter seasons were lower than under the spring-summer seasons. Soil losses showed a positive correlation with rainfall erosivity. However, the degree of dependence between these two variables decreased as the efficiency of soil management in controlling soil erosion increased. The large soil and water losses in the BS and CT treatments suggest that there is a need to implement soil conservation measures in the study region. In this context soil conservation would take advantage from soil cover by previous crop residue as well as from terrace building. Acknowledgement: This work was partly supported by Spanish Ministry of Education (Project CGL2005-08219-C02).

  2. ECONOMIC VIABILITY OF CROPS ROTATION AND GREEN MANURING PRECEDING THE CULTIVATION OF NO-TILL SYSTEM CORN IN THE CERRADO

    Directory of Open Access Journals (Sweden)

    AGUINALDO JOSÉ FREITAS LEAL

    2005-12-01

    Full Text Available In search of minimizing the environmental impacts of agricultural production it is necessary the use of techniques which make larger production sustainability possible and bring economic return to the producer. In this context, the present work had the objective to evaluate, in a typical Cerrado soil, the economic viability of crops rotation and green manure (Cajanus cajan (L. Millsp; Crotalaria juncea (L.; Eleusine coracana (L.; Pennisetum americanum (L. or fallow land in the yield of corn cultivated in notill system. The production information used were collected in the 2003/2004 harvest, in a test carried out in Selvíria, Mato Grosso do Sul, and the costs of farm inputs and production price were obtained in September 2004. The method used was the Total Operational Cost. To determine the profit of the activity for each treatment were considered the gross revenue, the operational profit, the profitability index and the balance price. The corn in rotation system with soybean obtained larger grains yield and higher profitability. The use of green manure preceding the cultivation of the corn was proven economically viable, and the use of the C. juncea allowed larger economic return, without showing significant difference between the E. coracana and the P. americanumt.

  3. 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

  4. 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.

  5. 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.

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

    Scientific Electronic Library Online (English)

    Jeanne Christine Claessen de, Miranda; Lourival, Vilela; Leo Nobre de, Miranda.

    1005-10-01

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

  7. 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

  8. Accounting for soil biotic effects on soil health and crop productivity in the design of crop rotations.

    Science.gov (United States)

    Dias, Teresa; Dukes, Angela; Antunes, Pedro M

    2015-02-01

    There is an urgent need for novel agronomic improvements capable of boosting crop yields while alleviating environmental impacts. One such approach is the use of optimized crop rotations. However, a set of measurements that can serve as guiding principles for the design of crop rotations is lacking. Crop rotations take advantage of niche complementarity, enabling the optimization of nutrient use and the reduction of pests and specialist pathogen loads. However, despite the recognized importance of plant-soil microbial interactions and feedbacks for crop yield and soil health, this is ignored in the selection and management of crops for rotation systems. We review the literature and propose criteria for the design of crop rotations focusing on the roles of soil biota and feedback on crop productivity and soil health. We consider that identifying specific key organisms or consortia capable of influencing plant productivity is more important as a predictor of soil health and crop productivity than assessing the overall soil microbial diversity per se. As such, we propose that setting up soil feedback studies and applying genetic sequencing tools towards the development of soil biotic community databases has a strong potential to enable the establishment of improved soil health indicators for optimized crop rotations. PMID:24408021

  9. 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.

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

    OpenAIRE

    Triplett, Eric W.; Cimelio Bayer; Camargo, Flavio A. O.; Fagen, Jennie R.; Jennifer Drew; Kateryna Zhalnina; Austin Davis-Richardson; Patricia Dorr de Quadros

    2012-01-01

    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 regim...

  11. Alterações na fertilidade do solo em sistemas de rotação de culturas em semeadura direta / Soil fertility changes on no-tillage crop rotation systems

    Scientific Electronic Library Online (English)

    J. C., Franchini; C. M., Borkert; M. M., Ferreira; C. A., Gaudêncio.

    2000-06-01

    Full Text Available O sistema de semeadura direta com culturas de grãos ocupa atualmente 2,5 milhões de hectares no estado do Paraná. Além do sistema tradicional de sucessão trigo-soja, em grande parte desta área são semeadas plantas de cobertura-adubação verde no inverno e milho no verão. Neste estudo, foram avaliadas [...] as alterações em algumas características químicas do solo, após sete anos, sob os sistemas de rotação de culturas trigo-soja-aveia-soja (TSA), trigo-soja-tremoço-milho-aveia-soja (TMA), tremoço-milho-trigo-soja (TM) e o sistema tradicional de sucessão trigo-soja (TS) em unidades de Latossolo Roxo distrófico, em Londrina e Campo Mourão. O sistema TM diminuiu o pH do solo e os teores de cálcio (Ca2+) e magnésio (Mg2+) trocáveis e aumentou o alumínio trocável (Al3+), a acidez potencial (H + Al) e o N-total do solo em relação ao sistema TS. Essas caracaterísticas apresentaram valores intermediários nos demais sistemas. Não foram observadas diferenças entre os sistemas quanto aos teores de carbono orgânico e potássio trocável (K+) no solo. A diminuição do teor de Ca2+ no sistema TM foi maior do que a quantidade de Ca aplicado na forma de calcário durante o experimento. A adubação nitrogenada no trigo e no milho foi relacionada com a acidificação observada no solo. A manutenção dos níveis de K+ e diminuição dos níveis de Ca2+ e Mg2+ resultaram provavelmente de uma alteração na preferência de lixiviação de cátions no sistema TM. A formação de complexos orgânicos com cátions divalentes foi sugerida como provável mecanismo responsável por estas alterações químicas no solo. Abstract in english The no-tillage system with grain crops occupies today 2.5 millions hectares in the state of Paraná. Besides the traditional rotation system with wheat and soybean, in many areas green manure cover crops are also sown in the Winter and corn in the Summer. The objective of this study was to evaluate c [...] hanges in some of the soil chemical properties after eight years under the crop rotation systems: wheat-soybean-black oat-soybean (WOS), wheat-soybean-lupine-corn-black oat-soybean (LCO), lupine-corn-wheat-soybean (LC) and compare them with the traditional system wheat-soybean (WS) grown in two Oxisols at Londrina and Campo Mourão, State of Paraná, Brazil. The LC crop rotation system reduced the soil pH and the level of exchangeable calcium (Ca2+) and magnesium (Mg2+) and increased the excangeable aluminum (Al3+), the potential acidity (H + Al), and the total-N in the soil as compared to the WS system. These characteristics showed intermediate values in the other systems. There were no significant differences on soil levels of organic carbon and exchangeable-K (K+) among the crop rotation systems. The decrease on the level of Ca2+ in the LC system was larger than the amount of Ca applied as lime to the soil during the experiment. Soil acidification was related to the nitrogen fertilization of wheat and corn. The maintenance of levels of K+ and the decrease on the levels of Ca2+ and Mg2+ demonstrate that there was a change in the preference of leaching cations in the LC crop rotation system. The formation of metal-organic complexes with divalent cations was assumed to be the possible mechanism responsible for the chemical alterations in the soil.

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

    Directory of Open Access Journals (Sweden)

    Paulo E Trani

    2006-03-01

    Full Text Available A quantidade de calcário indicada de forma rotineira para hortaliças tem pouca experimentação de campo para dar suporte a níveis de aplicação. Neste trabalho procurou-se estabelecer valores para a saturação por bases (V e pH (CaCl2 para melhor produtividade e qualidade de cenoura (de inverno e alface (de verão, cultivadas sucessivamente por três anos agrícolas em um Argissolo Vermelho Amarelo em Monte Alegre do Sul (SP. Avaliou-se a calagem aplicada no ano, bem como o efeito residual da calagem no segundo e terceiro anos subseqüentes. Os tratamentos utilizados foram: 0; 2; 4; 6 e 8 t ha-1 de calcário no primeiro ano, e 4 e 8 t ha-1 de calcário no segundo e terceiro anos. Constatou-se efeito positivo da calagem sobre a produção e qualidade comercial da cenoura e da alface nos três anos agrícolas e efeito residual da calagem aplicada no primeiro ano do experimento sobre as produções de cenoura e alface nos anos seguintes. No primeiro ano, a produtividade de cenoura comercial foi de 24% a 39% maior do que a testemunha sem calcário, enquanto o peso médio da cabeça de alface aumentou de 79% a 199%. As maiores produtividades de cenoura foram de 46 t ha-1 obtidas com V=73% e pH (CaCl2= 5,7. As melhores produções de alface foram atingidas com V entre 72% e 80% e o pH (CaCl2 entre 5,5 e 5,6. A omissão de B, Cu, Mn e Zn em um dos tratamentos com calagem acarretou na queda de produtividade e qualidade da cenoura nos três anos agrícolas.Amounts of lime recommended for carrots and lettuce have little experimental support for the amounts indicated. This research was developed to determine the adequate value of soil bases saturation (V and pH (CaCl2 to obtain the best yield and commercial quality of carrot (winter and lettuce (summer cultivated on crop rotation system during three years. The experiment was carried out in Monte Alegre do Sul, São Paulo State, Brazil, on a Typic Kandaudult soil. The residual effect of liming, at the second and third years, was also evaluated. The treatments were: 0; 2; 4; 6 and 8 t ha-1 of lime on the first year; 4 and 8 t ha-1 of lime on the second and third years successively. As a result, the positive effects of liming on yield and commercial quality of carrot and lettuce were evident during the three years, and residual effect of liming in the second and third years was evident, too. In the first year, carrot yields were 24% to 39% higher than treatment without lime, while lettuce head average weight increased from 79% to 199%. The highest carrot yields were 46 t ha-1 obtained at V=73% and pH (CaCl2 = 5,7. The best commercial results for lettuce were reached with V between 72% and 80% and pH (CaCl2 between 5,5 and 5,6. The treatment with liming and without B, Cu, Mn and Zn presented lower carrot yield and commercial quality during three years.

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

    Scientific Electronic Library Online (English)

    Paulo E, Trani; Keigo, Minami; Bernardo, van Raij; Emílio, Sakai; Simone C, Mello; Sebastião W, Tivelli.

    2006-03-01

    Full Text Available A quantidade de calcário indicada de forma rotineira para hortaliças tem pouca experimentação de campo para dar suporte a níveis de aplicação. Neste trabalho procurou-se estabelecer valores para a saturação por bases (V) e pH (CaCl2) para melhor produtividade e qualidade de cenoura (de inverno) e al [...] face (de verão), cultivadas sucessivamente por três anos agrícolas em um Argissolo Vermelho Amarelo em Monte Alegre do Sul (SP). Avaliou-se a calagem aplicada no ano, bem como o efeito residual da calagem no segundo e terceiro anos subseqüentes. Os tratamentos utilizados foram: 0; 2; 4; 6 e 8 t ha-1 de calcário no primeiro ano, e 4 e 8 t ha-1 de calcário no segundo e terceiro anos. Constatou-se efeito positivo da calagem sobre a produção e qualidade comercial da cenoura e da alface nos três anos agrícolas e efeito residual da calagem aplicada no primeiro ano do experimento sobre as produções de cenoura e alface nos anos seguintes. No primeiro ano, a produtividade de cenoura comercial foi de 24% a 39% maior do que a testemunha sem calcário, enquanto o peso médio da cabeça de alface aumentou de 79% a 199%. As maiores produtividades de cenoura foram de 46 t ha-1 obtidas com V=73% e pH (CaCl2)= 5,7. As melhores produções de alface foram atingidas com V entre 72% e 80% e o pH (CaCl2) entre 5,5 e 5,6. A omissão de B, Cu, Mn e Zn em um dos tratamentos com calagem acarretou na queda de produtividade e qualidade da cenoura nos três anos agrícolas. Abstract in english Amounts of lime recommended for carrots and lettuce have little experimental support for the amounts indicated. This research was developed to determine the adequate value of soil bases saturation (V) and pH (CaCl2) to obtain the best yield and commercial quality of carrot (winter) and lettuce (summ [...] er) cultivated on crop rotation system during three years. The experiment was carried out in Monte Alegre do Sul, São Paulo State, Brazil, on a Typic Kandaudult soil. The residual effect of liming, at the second and third years, was also evaluated. The treatments were: 0; 2; 4; 6 and 8 t ha-1 of lime on the first year; 4 and 8 t ha-1 of lime on the second and third years successively. As a result, the positive effects of liming on yield and commercial quality of carrot and lettuce were evident during the three years, and residual effect of liming in the second and third years was evident, too. In the first year, carrot yields were 24% to 39% higher than treatment without lime, while lettuce head average weight increased from 79% to 199%. The highest carrot yields were 46 t ha-1 obtained at V=73% and pH (CaCl2) = 5,7. The best commercial results for lettuce were reached with V between 72% and 80% and pH (CaCl2) between 5,5 and 5,6. The treatment with liming and without B, Cu, Mn and Zn presented lower carrot yield and commercial quality during three years.

  14. 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

  15. From Monoculture to Norfolk System: How the Number of Crops in Rotation Can Influence the Biodiversity of Arbuscular Mycorrhiza Assemblages in the Soil

    Directory of Open Access Journals (Sweden)

    Franco Magurno

    2014-12-01

    Full Text Available Given the attention drawn since several decades by arbuscular mycorrhizal fungi (AMF as potential biological alternatives to chemicals in a low-input agriculture, much effort has been spent in the investigation of mechanisms influencing the dynamics inside AMF communities. In the present study we evaluated the influence of different crop rotations on the AMF soil community, after a 50 y long-term field experiment established at Martonvásár, Hungary. Four types of crop rotation were chosen for sampling: corn monocropping, corn-alfalfa, corn-wheat, and corn-spring barley-peas-wheat. Community composition of AMF in soil was analyzed with a molecular approach amplifying a portion of 28S rDNA. The crop rotation practice didn’t show an influence on identity of the species composing AMF assemblages, but on the other hand seemed to affect positively the true diversity, defined as number of MOTUs present in the communities.

  16. Evaluation of Maize Yield in an On-Farm Maize-Soybean and Maize-Lablab Crop Rotation Systems in the Northern Guinea Savanna of Nigeria

    OpenAIRE

    J.A. Okogun; Sanginga, N.; Abaidoo, R.C.

    2007-01-01

    An attempt was made to solving the problem of shortfall of fertilizer to maize production in the Northern Guinea Savanna (NGS) of Nigeria by harnessing the potentials of legume/cereal crop rotation in on-farm trials. The yield of maize that succeeded two soybean varieties and Lablab in a two-cycle of soybean/maize and Lablab/maize crop rotation in NGS Nigeria was assessed in researcher-managed and farmer-managed plots. Though maize that followed the soybean received between 5 kg N ha-1 from i...

  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. 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.

  19. 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.

  20. 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)

  1. 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: 5.510, year: 2013

  2. 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...

  3. 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...

  4. Cereal-forage crop rotations and irrigation treatment effect on water use efficiency and crops sustainability in Mediterranean environment

    Directory of Open Access Journals (Sweden)

    Pasquale Martiniello

    2012-01-01

    Full Text Available Agricultural systems based on crop rotations favour sustainability of cultivation and productivity of the crops. Wheat-forage crops rotations (annual winter binary mixture and perennial alfalfa meadow combined with irrigation are the agronomical techniques able to better exploit the weather resources in Mediterranean environments. The experiment aimed to study the effect of 18 years of combined effect of irrigation and continuous durum wheat and wheat-forage rotations on productivities of crops and organic matter of topsoil. The experiments were established through 1991-2008 under rainfed and irrigated treatments and emphasized on the effect of irrigation and continuous wheat and wheat-forage crop rotations on water use efficiency and sustainability of organic matter. The effect of irrigation increased 49.1% and 66.9% the dry matter of mixture and meadow, respectively. Continuous wheat rotation reduced seed yield, stability of production, crude protein characteristics of kernel and soil organic matter. 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 crude protein and soil organic matter of wheat rotations, compared to those of continuous wheat under rainfed and irrigated was increase in term of point percentage by 0.8 and 0.5 in crude protein and 5.1 and 4.4 in organic matter, respectively. The rotations of mixture and meadow under both irrigated treatments increased the point of percentage of organic matter over continuous wheat (9.3.and 8.5 in mixture and 12.5 and 9.5 meadow under rainfed and irrigation, respectively. Irrigation reduce the impact of weather on crop growing reducing water use efficiency (mean over rotations for dry mater production (15.5 in meadow and 17.5 in mixture [L water (kg·dry·matter-1 ] and wheat seed yield. The effect of agronomic advantages achieved by forage crops in topsoil expire its effect after three years of continuous wheat rotation.

  5. EFFECT OF CROP ROTATION/TILLAGE SYSTEMS ON COTTON YIELD IN THE TENNESSEE VALLEY AREA OF ALABAMA, 1980-2001

    Science.gov (United States)

    A replicated cotton (Gossypium hirsutum L.) rotation experiment has been conducted for 22 years on a Decatur silt loam (fine, kaolinitic, thermic, Rhodic Paleudults) in the Tennessee Valley of northern Alabama. The highly productive soil with little disease and nematode problems resulted in cotton ...

  6. 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.

  7. 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.

  8. 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.

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

    OpenAIRE

    Berg, F; Gilligan, C A; Gerdessen, J.C.; Gregoire, L.A.H.; Bosch, F.

    2010-01-01

    Although the effects of crop rotation sequence and length on weed population dynamics have been studied, it is not clear whether or not the best strategy, from a weed population dynamics point of view, is also the economic optimal strategy. It is also not clear which biological and economic parameters are most important in determining this optimal strategy. We use a density-dependent periodic matrix model, integrated with an economic model, to study the effect of rotation length and weed cont...

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

    Directory of Open Access Journals (Sweden)

    Botir Khaitov

    2014-01-01

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

  11. 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.

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

    Directory of Open Access Journals (Sweden)

    Salvatore Claps

    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.

  13. Greenhouse gas emissions from traditional and biofuels cropping systems

    Science.gov (United States)

    Cropping systems can have a tremendous effect on the greenhouse gas emissions from soils. The objectives of this study were to compare greenhouse gas emissions from traditional (continuous corn or corn/soybean rotation) and biomass (miscanthus, sorghum, switchgrass) cropping systems. Biomass croppin...

  14. Methane production through anaerobic digestion of various energy crops grown in sustainable crop rotations.

    Science.gov (United States)

    Amon, Thomas; Amon, Barbara; Kryvoruchko, Vitaliy; Machmüller, Andrea; Hopfner-Sixt, Katharina; Bodiroza, Vitomir; Hrbek, Regina; Friedel, Jürgen; Pötsch, Erich; Wagentristl, Helmut; Schreiner, Matthias; Zollitsch, Werner

    2007-12-01

    Biogas production is of major importance for the sustainable use of agrarian biomass as renewable energy source. Economic biogas production depends on high biogas yields. The project aimed at optimising anaerobic digestion of energy crops. The following aspects were investigated: suitability of different crop species and varieties, optimum time of harvesting, specific methane yield and methane yield per hectare. The experiments covered 7 maize, 2 winter wheat, 2 triticale varieties, 1 winter rye, and 2 sunflower varieties and 6 variants with permanent grassland. In the course of the vegetation period, biomass yield and biomass composition were measured. Anaerobic digestion was carried out in eudiometer batch digesters. The highest methane yields of 7500-10200 m(N)(3)ha(-1) were achieved from maize varieties with FAO numbers (value for the maturity of the maize) of 300 to 600 harvested at "wax ripeness". Methane yields of cereals ranged from 3200 to 4500 m(N)(3)ha(-1). Cereals should be harvested at "grain in the milk stage" to "grain in the dough stage". With sunflowers, methane yields between 2600 and 4550 m(N)(3)ha(-1) were achieved. There were distinct differences between the investigated sunflower varieties. Alpine grassland can yield 2700-3500 m(N)(3)CH(4)ha(-1). The methane energy value model (MEVM) was developed for the different energy crops. It estimates the specific methane yield from the nutrient composition of the energy crops. Energy crops for biogas production need to be grown in sustainable crop rotations. The paper outlines possibilities for optimising methane yield from versatile crop rotations that integrate the production of food, feed, raw materials and energy. These integrated crop rotations are highly efficient and can provide up to 320 million t COE which is 96% of the total energy demand of the road traffic of the EU-25 (the 25 Member States of the European Union). PMID:16935493

  15. 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

  16. Potential biomass production of a short rotation crop in Portugal

    OpenAIRE

    Patrício, Maria do Sameiro; Nunes, Luís; Saraiva, Daniel; Azevedo, JOão

    2011-01-01

    There is a growing consensus that CO2 emissions from burning fossil fuels are altering the global climate. The Portuguese government aims to reduce national CO2 emissions by 8 %, at the levels of 1990, by 2012. The use of short rotation crops (SRC) such as willow and poplar as an energy source that produces very low net CO2 emissions could help meet these targets. In 2008, in the framework of the research project PTDC/AGR-CFL/64500/2006, a SRC crop was established in the Trás-os-Montes Region...

  17. 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

  18. 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

  19. 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.

  20. 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.

    Science.gov (United States)

    Soler, C M Tojo; Bado, V B; Traore, K; Bostick, W McNair; Jones, J W; Hoogenboom, G

    2011-10-01

    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 experiment conducted in Farakô-Ba, Burkina Faso was used to evaluate the performance of the cropping system model (CSM) of the Decision Support System for Agrotechnology Transfer (DSSAT) for simulating yield of different crops. Eight crop rotations that included cotton, sorghum, peanut, maize and fallow, and three different management scenarios, one without N (control), one with chemical fertilizer (N) and one with manure applications, were studied. The CSM was able to simulate the yield trends of various crops, with inconsistencies for a few years. The simulated SOC increased slightly across the years for the sorghum-fallow rotation with manure application. However, SOC decreased for all other rotations except for the continuous fallow (native grassland), in which the SOC remained stable. The model simulated SOC for the continuous fallow system with a high degree of accuracy normalized root mean square error (RMSE)=0·001, while for the other crop rotations the simulated SOC values were generally within the standard deviation (s.d.) range of the observed data. The crop rotations that included a supplemental N-fertilizer or manure application showed an increase in the average simulated aboveground biomass for all crops. The incorporation of this biomass into the soil after harvest reduced the loss of SOC. In the present study, the observed SOC data were used for characterization of production systems with different SOC dynamics. Following careful evaluation of the CSM with observed soil organic matter (SOM) data similar to the study presented here, there are many opportunities for the application of the CSM for carbon sequestration and resource management in Sub-Saharan Africa. PMID:22505776

  1. 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

    Directory of Open Access Journals (Sweden)

    Eurâimi de Q. Cunha

    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 orgânica 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.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 the 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.

  2. 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.

  3. 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

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

    DEFF Research Database (Denmark)

    Hansen, Elly MØller; Munkholm, Lars Juhl

    2010-01-01

    Finding ways of reducing nitrate leaching in Northern Europe has become an extremely important task, especially under the projected climate changes that are expected to exacerbate the problem. To this end, two field experiments were established under temperate coastal climate conditions to evaluate the effect of tillage, straw retainment and cropping sequences, including cover crops, on nitrate leaching. The experiments were established in autumn 2002 on a loamy sand with 92 g clay kg-1 and a sandy loam with 147 g clay kg-1. The tillage treatments were stubble cultivation to 8-10 cm or 3-4 cm, direct drilling, or ploughing to 20 cm. The hypothesis was that (i) decreasing soil tillage intensity would decrease leaching compared to ploughing, (ii) leaving straw in the field would decrease leaching compared to removing straw, and (iii) a spring/winter crop rotation with catch crops would be more efficient in reducing nitrate leaching than a winter crop rotation. Overall, we were not able to confirm the three hypotheses. The effect of soil tillage on leaching might be blurred because the studied crop rotations had a high proportion of winter crops and because catch crops were grown whenever the alternative would have been bare soil in autumn and winter. The spring/winter crop rotation with catch crops was not found to be more efficient in reducing nitrate leaching than the winter crop rotation. In contrast, in a single year the winter crop rotation showed significantly lower leaching than the spring/winter crop rotations, probably due to the spring/winter crop rotation including peas, which may be considered a high-risk crop. Our study highlights that management practices that improve biomass production throughout the year are crucial in order to tighten the nitrogen cycle and thereby reduce nitrate leaching.

  5. 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.

  6. Teores de nutrientes e de matéria orgânica afetados pela rotação de culturas e sistema de preparo do solo / Nutrient availability and soil organic matter as affected by crop rotations and soil tillage systems

    Scientific Electronic Library Online (English)

    P. M., Silveira; L. F., Stone.

    2001-06-01

    Full Text Available Este trabalho foi realizado na Embrapa Arroz e Feijão, em Santo Antônio de Goiás (GO), em Latossolo Vermelho perférrico, sob pivô central, por seis anos consecutivos, durante os quais se efetuaram 12 cultivos. Estudaram-se os efeitos de quatro sistemas de preparo do solo e seis rotações de culturas [...] sobre o pH em água, Al e Ca + Mg trocáveis, teor de matéria orgânica, P extraível e K trocável . Foi utilizado o delineamento inteiramente casualizado, em parcelas subdivididas, com três repetições. As parcelas foram constituídas pelos sistemas de preparo: arado/grade, arado, grade e plantio direto; as subparcelas, pelas rotações: (a) arroz-feijão, (b) milho-feijão, (c) soja-trigo, (d) soja-trigo-soja-feijão-arroz-feijão, (e) arroz consorciado com calopogônio-feijão e (f) milho-feijão-milho-feijão-arroz-feijão. As rotações a, b, c e e foram anuais e as d e f, trienais. As diferenças observadas entre os sistemas de preparo do solo, quanto aos valores de pH, Al e Ca + Mg trocáveis, deveram-se à profundidade de mobilização do solo e à incorporação do calcário. A distribuição do K trocável e do P extraível no perfil do solo variou com a profundidade do solo mobilizada pelos diferentes sistemas de preparo, especialmente no caso do P, em que a menor mobilização causou maior concentração na camada superficial. Os sistemas de rotação que incluíram soja propiciaram maiores valores de pH e Ca + Mg trocáveis e menores de Al trocável. Os sistemas de preparo do solo e de rotação mantiveram, após 12 cultivos, teores de matéria orgânica do solo semelhantes aos iniciais. Abstract in english An experiment, covering 12 cultivations, was carried out at Embrapa Rice & Beans Research Center, Santo Antônio de Goiás, Goiás, Brazil, in an Oxisol under center pivot, for six consecutive years. The effects of four soil tillage systems and six crop rotations on pH in water, exchangeable Al and Ca [...] + Mg, organic matter, extractable P, and exchangeable K were evaluated, using a completely randomized design, in a splitplot arrangement, with three replications. The tillage treatments were: moldboard plough/harrow disc, moldboard plough, harrow disc, and no-tillage. Tillage treatments constituted the main plots and the rotation treatments, the subplots. The crop rotations were: (a) upland rice-common bean, (b) corn-common bean, (c) soybean-wheat, (d) soybean-wheat-soybean-common bean-upland rice-common bean, (e) upland rice associated to calopogonium-common bean, and (f) corn-common bean-corn-common bean-upland rice-common bean. Crop rotations a, b, c, and e were annuals and d and f were of three years'duration. Differences observed among soil tillage treatments in relation to pH and exchangeable Al and Ca + Mg were due to the depth of soil turnover and lime incorporation. The distribution of exchangeable K and extractable P in the soil profile varied with the depth of soil turnover. Tillage systems that cause less soil turnover improved P concentration at upper soil surface layer. Crop rotations including soybean showed higher pH and exchangeable Ca + Mg and lower exchangeable Al than other rotations. Soil tillage systems and rotations maintained soil organic matter at initial level after 12 cultivations.

  7. Faba bean in cropping systems

    OpenAIRE

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

    2011-01-01

    The grain legume (pulse) faba bean (Vicia faba L.) is grown world-wide as protein source for food and feed, but 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 ...

  8. 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.

  9. 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

  10. 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.

  11. 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 ...

  12. 7 CFR 205.205 - Crop rotation practice standard.

    Science.gov (United States)

    2010-01-01

    ...AGRICULTURE (CONTINUED) ORGANIC FOODS PRODUCTION ACT PROVISIONS NATIONAL ORGANIC PROGRAM Organic Production and Handling Requirements § 205.205...but not limited to sod, cover crops, green manure crops, and catch crops...

  13. 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.

    1794-18-01

    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.

  14. 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

  15. Rotating Aperture System

    Science.gov (United States)

    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.

  16. 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.

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

    Directory of Open Access Journals (Sweden)

    Eva Haná?ková

    2009-03-01

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

  18. 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

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

    Scientific Electronic Library Online (English)

    Maria Eloneide de Jesus, Bezerra; Claudivan Feitosa de, Lacerda; Geocleber Gomes de, Sousa; Vânia Felipe Freire, Gomes; Paulo Furtado, Mendes Filho.

    2010-12-01

    Full Text Available O objetivo deste trabalho foi avaliar a influência da irrigação com água de alta e baixa salinidade sobre variáveis microbiológicas do solo em área submetida à rotação de cultura entre milho (Zea Mays L.) e feijão-de-corda (Vigna unguiculata L.). A área destinada ao experimento foi dividida em duas [...] subáreas, sendo realizados quatro cultivos: dois cultivos irrigados na estação seca e dois de sequeiro na estação chuvosa. O estudo foi conduzido em campo, utilizando-se o delineamento em blocos ao acaso, com cinco repetições. Nos cultivos irrigados foram usadas água com as seguintes condutividades elétricas (CEa): 0,8; 2,2; 3,6 e 5,0 dS m-1. Os cultivos de sequeiro foram realizados nas mesmas parcelas que foram cultivadas na estação seca, as quais permaneceram demarcadas e identificadas. No início e ao final de cada cultivo, foram coletadas amostras em duas subáreas na região radicular das plantas, no terço médio da fileira central de cada parcela. O aumento da salinidade da água de irrigação promoveu aumento do número total de esporos de fungos micorrízicos arbusculares FMA e reduziu a respiração basal do solo, o carbono da biomassa e o coeficiente metabólico microbiano (qCO2), principalmente na área cultivada com feijão-de-corda. O gênero Glomus respondeu por mais de 70% dos esporos totais encontrados, sendo que essa percentagem aumentou nos tratamentos com maior salinidade nos cultivos da estação seca. Os dados não evidenciaram qualquer efeito negativo da salinidade residual sobre as variáveis microbiológicas avaliadas, em função da irrigação com água salina durante os cultivos da estação seca. Abstract in english This work carred out the influence of irrigation with water of high and low salinity on soil microbial variables in area under the crop rotation between maize (Zea Mays L.) and cowpea (Vigna unguiculata L.). The area for the experiment was divided into two sub areas being made four crops, two crops [...] irrigated in the dry season and two dry in the rainy season. The study was conducted under field conditions using a randomized block design with five replications. In irrigated crops were used the following water with electrical conductivity (ECw): 0.8; 2.2; 3.6 and 5.0 dS m-1. The rainfed crops were conducted on the same plots that were cultivated during the dry season, which remained demarcated and identified. At the beginning and end of each crop were collected samples in two subareas in the region of root system plant, in the middle third of the central row of each plot. Increasing of salinity in irrigation water led to increase in the total number of spores and reduced soil basal respiration, biomass carbon and microbial metabolic coefficient (qCO2), mainly in the area cultivated with cowpea. The genus Glomus accounted for more than 70% of total spores found, and this percentage increased in treatments with high salinity in dry season crops. The data reveal no residual negative effect of salinity on the microbial variables assessed in function irrigation with saline water during the dry season crops.

  20. 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

  1. 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.

  2. 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.

  3. 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.

  4. 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

  5. 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 inal 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)

  6. Management of Lesion Nematodes and Potato Early Dying with Rotation Crops

    OpenAIRE

    Lamondia, J. A.

    2006-01-01

    Soil-incorporated rotation/green manure crops were evaluated for management of potato early dying caused by Verticillium dahliae and Pratylenchus penetrans. After two years of rotation/green manure and a subsequent potato crop, P. penetrans numbers were less after ‘Saia’ oat/‘Polynema’ marigold, ‘Triple S’ sorghum-sudangrass, or ‘Garry’ oat than ‘Superior’ potato or ‘Humus’ rapeseed. The area under the disease progress curve (AUDPC) for early dying was lowest after Sai...

  7. Influence of Cover Crops in Rotation on Populations of Soil Nematodes

    Science.gov (United States)

    A pot experiment was carried out in south Florida to elucidate suppressive or antagonistic effects of several cover crops grown in rotation on soil nematode populations. The crops were two marigolds, Tagetes patula L. 'Dwarf Double French Mix' (MI), and Tagetes patula L. 'Lemon Drop' (MII), Indian m...

  8. 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...

  9. 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.

  10. 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.

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

    Directory of Open Access Journals (Sweden)

    Sukhdev S. Malhi

    2012-10-01

    Full Text Available 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 resistant hybrid and monoculture pea compared with rotations that contained these crops every 2-, 3-, and 4-yr with wheat. There was no effect of crop rotation duration and crop phase on soil pH. Mass of TOC and TON in the 0 - 15 cm soil was greater in canola phase than pea phase in the 1-yr (monoculture and 2-yr crop rotations, while the opposite was true in the 3-yr and 4-yr crop rotations. Mass of TOC and TON (averaged across crop phases, in soil generally increased with increasing crop rotation duration, with the maximum in the 4-yr rotation while no difference in the 1-yr and 2-yr rotations. Mass of LFOC and LFON in soil was greater in canola phase than pea phase in the 1-yr, 2-yr and 3-yr rotations, but the opposite was true in the 4-yr rotation. There was no consistent effect of crop rotation duration on mass of LFOC and LFON. The N balance sheet over the 1998 to 2009 period indicated large amounts of unaccounted N for monoculture pea, suggesting a great potential for N loss from the soil-plant system in this treatment through nitrate leaching and/or denitrification. In conclusion, the findings suggest that the quantity of organic C and N can be maximized by increasing duration of crop rotation and by including hybrid canola in the rotation.

  12. Tracking nitrogen losses in a greenhouse crop rotation experiment in North China using the EU-Rotate{sub N} simulation model

    Energy Technology Data Exchange (ETDEWEB)

    Guo Ruiying [Ministry of Education Key Laboratory of Arid and Grassland Ecology, School of Life Sciences, Lanzhou University, No. 222 Tianshui Nanlu, Lanzhou 730000, Gansu Province (China); Nendel, Claas, E-mail: nendel@zalf.d [Institute for Landscape Systems Analysis, Leibniz-Center for Agricultural Landscape Research, Eberswalder Strasse 84, 15374 Muencheberg (Germany); Rahn, Clive [Warwick HRI, Wellesbourne CV35 9EF (United Kingdom); Jiang Chunguang; Chen Qing [College of Resources and Environmental Sciences, China Agricultural University, No. 2 Yuanmingyuan Xilu, Haidian, Beijing 100193 (China)

    2010-06-15

    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-Rotate{sub N} simulation model. EU-Rotate{sub N} 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-Rotate{sub N} model can satisfactorily simulate crop N uptake and N{sub min} dynamics in a typical greenhouse cucumber production system of North China

  13. 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.

  14. 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.

  15. Soybean benefit to a subsequent wheat crop in a cropping system under zero tillage

    International Nuclear Information System (INIS)

    This experiment was conducted to compare biological nitrogen fixation (BNF) contributions to soybean crops and the effect of the presence of its residues to the production of wheat under two tillage systems. The plots were established in the experimental area of the Embrapa Soybean Centre in the State of Parana, southern Brazil. A soybean/wheat rotation was planted under conventional and zero tillage (CT and ZT, respectively). The contribution of BNF to soybean was assessed using the ?15N technique and the relative abundance of ureides. An N balance was performed based on the dry matter and N content of, and the BNF contribution to, the whole crop. Plant-residue decomposition was evaluated by field sampling. Wheat responses to the previous soybean crop and tillage treatments were evaluated from the wheat yields and the 'A'-value technique. Comparing ZT and CT, there were no marked differences in grain yield or N accumulation by the crops, but BNF was higher in the soybean under ZT. Although for both tillage systems the BNF contribution to soybean was over 170 kg N/ha, the benefit to the subsequent crop was due to the release of N from extremely labile soybean residues of low C:N ratio and not because of a net gain of N from BNF. (author)

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

    Directory of Open Access Journals (Sweden)

    Elcio Liborio Balota

    2004-12-01

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

  17. Effects of crop rotation on the incidence of soil-borne pathogens and the consequences for potato production.

    OpenAIRE

    Scholte, K.

    1989-01-01

    This thesis describes the effects of various rotations on the growth pattern, yield and quality of potato and on the incidence of soil-borne pathogens, other than potato cyst nematodes ( Globodera spp.), associated with potato. These rotations differed in the frequency of potato and in the crops with which the potato crop was rotated.The effects of the rotations depended greatly on the soil type. Lower yields of potato in short rotations were mainly caused by Streptomyces spp. (causing netted...

  18. 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 inthe 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).

  19. 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.

  20. 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.

  1. 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

    Directory of Open Access Journals (Sweden)

    Gustavo Spadotti Amaral Castro

    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 parcelas 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.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 replicates. 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.

  2. 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.

    1690-16-01

    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.

  3. 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.

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

    Directory of Open Access Journals (Sweden)

    Erlei Melo Reis

    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 manejo 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.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 rotation 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.

  5. 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.

  6. 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.

  7. 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....

  8. 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.

  9. 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

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

    Directory of Open Access Journals (Sweden)

    M. H. Jeuffroy

    2012-07-01

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

  12. 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.

  13. 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.

  14. 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

  15. 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

    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.

  16. Effect of Crop Rotation on the Soil Pathogen Population Dynamics and Canola Seedling Establishment

    Directory of Open Access Journals (Sweden)

    S.F. Hwang

    2009-01-01

    Full Text Available Impact of long-term crop rotations on populations of soilborne pathogens in the genera Fusarium, Pythium and Rhizoctonia and on canola seedling establishment and development was evaluated under controlled conditions. Soil samples were collected from two crop rotation experiments conducted at two sites in Saskatchewan, Canada. A part of the 2006-soil sample of each rotation was sterilized to compare canola seedling growth with and without soilborne pathogens. With 2007-soil, the sterilization treatment was replaced with a fungicide seed treatment (Apron Maxx to assess the potential to reduce seedling diseases. Populations of Fusarium, Pythium and Rhizoctonia sp. were estimated in the soil of each rotation using dilution plating onto selective media for each fungus. Higher seedling emergence and increased growth of canola were obtained in the sterilized soil or due to seed treatment. Fusarium was the predominant genus followed by Pythium and Rhizoctonia sp. in the soil of both sites. This study suggests that diverse crop in the rotation may reduce the populations of Fusarium, Pythium and Rhizoctonia in the soil and may contribute to improve the overall growth of canola.

  17. Biogas production from catch crops : Evaluation of biomass yield and methane potential of catch crops in organic crop rotations

    DEFF Research Database (Denmark)

    Molinuevo-Salces, Beatriz; Larsen, SØren U.

    2013-01-01

    Manure-based biogas plants in Denmark are dependent on high yielding biomass feedstock in order to secure economically feasible operation. The aim of this study was to investigate the potential of ten different catch crop species or mixtures as feedstock for biogas production in co-digestion with manure. The biomass yield per hectare and the specific methane yield of the catch crops in two different locations, namely Holstebro and Aabenraa, were investigated. The volatile solids (VS) yield per hectare was notably influenced by the differences in climate and soil conditions between the locations, being in the ranges of 1.4–3.0 t ha?1 and 0.3–1.7 t ha?1 for Holstebro and Aabenraa, respectively. Specific methane yields were in the range of 229–450 m3 t?1 of VS. Methane yields per hectare of up to 800 m3 ha?1 were obtained, making catch crops a promising source of feedstock for manure-based biogas plants in Denmark since this biomass is not competing with food/feed production.

  18. 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

    Directory of Open Access Journals (Sweden)

    E. V. Wohlenberg

    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 agregação 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.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 Hapludalf 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.

  19. 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.

  20. 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.

  1. Variabilidade espacial de atributos do solo em sistema de semeadura direta com rotação de culturas no cerrado brasileiro / Spatial variability of soil attributes in no a no-tillage system with crop rotation in the Brazilian savannah

    Scientific Electronic Library Online (English)

    Eduardo Leonel, Bottega; Daniel Marçal de, Queiroz; Francisco de Assis de Carvalho, Pinto; Cristiano Márcio Alves de, Souza.

    2013-03-01

    Full Text Available O presente estudo objetivou analisar a variabilidade espacial dos atributos químicos e da textura de um Latossolo Vermelho distroférrico. A propriedade onde o estudo foi realizado localiza-se no município de Sidrolândia (MS) e produz soja, milho e algodão, adotando rotação de culturas e o sistema de [...] plantio direto. Em uma área experimental de aproximadamente 90 hectares foi amostrado solo em 181 pontos georeferenciados. As amostras foram compostas por quatro amostras simples, representativas da profundidade de 0,00-0,20 m. Foram mensurados os atributos químicos e a textura do solo. Realizou-se, inicialmente, análise de discrepantes e, posteriormente, análise descritiva e geoestatística para caracterizar as amostras e identificar a dependência espacial dos atributos estudados. Não foi detectada dependência espacial para os atributos acidez ativa em água, alumínio, acidez potencial, saturação por bases e matéria orgânica. As melhores estimativas de valores para locais não amostrados foram observadas para os atributos físicos do solo, os quais apresentaram os melhores parâmetros de ajuste dos variogramas e da validação cruzada. As técnicas de geoestatística utilizadas possibilitaram o ajuste dos modelos teóricos que melhor representaram a semivariância experimental, possibilitando assim a construção de mapas temáticos da distribuição espacial dos valores dos atributos do solo estudado. Abstract in english This study aimed to analyze the spatial variability of the chemical attributes and texture of a red latosol. The study was carried out on a property in the town of Sidrolândia, Matto Grosso do Sul, which produces soybeans, corn and cotton, using crop rotation and a no-tillage system. In an experimen [...] tal area of approximately 90 hectares, samples were taken of the soil at 181 geo-referenced points. The samples were each composed of four single samples, representing depths of from 0 to 0.2 m. The chemical and texture of the soil were measured. Initially a discrepancy analysis was performed followed by descriptive and geostatistical analyses, to characterize the samples and identify the spatial dependence of the attributes studied. No spatial dependence was detected for the attributes: active water acidity, aluminum, potential acidity, base saturation and organic matter. The best estimates of values for non-sampled locations were observed for the physical properties of the soil, which presented parameters which best fit the variograms and cross-validation. The geostatistical techniques used allowed adjustment of the theoretical models that best represented the experimental semivariance, thus enabling the construction of thematic maps of spatial distribution for the values of the attributes of the studied soil.

  2. Climate change impact on crop rotations of winter durum wheat and tomato in southern Italy: yield analysis and soil fertility

    Directory of Open Access Journals (Sweden)

    Annamaria Castrignanò

    2012-03-01

    Full Text Available Cropping systems are affected by climate change because of the strong relationship between crop development, growth, yield, CO2 atmospheric concentration and climate conditions. The increasing temperatures and the reduction of available water resources may result in negative impacts on the agricultural activity in Mediterranean environments than other areas. In this study the CERES-Wheat and CROPGRO-Tomato models were used to assess the effects of climate change on winter wheat (Triticum durum L. and processing tomato (Lycopersicon aesculentum Mill. in one of most productive areas of Italy, located in the northern part of the Puglia region. In particular we have compared three different General Circulation Models (HadCM3, CCSM3, ECHAM5 subjected to a statistical downscaling under two future IPCC scenarios (B1 and A2. The analysis was carried out at regional scale repeating the simulations for seven homogeneous area characterizing the spatial variability of the region. In the second part of the study, considering only HadCM3 data set, climate change impact on long-term sequences of the two crops combined in three crop rotations were evaluated in terms of yield performances and soil fertility as indicated by the soil organic content of carbon and nitrogen. The comparison between GCMs showed no significant differences for winter durum wheat yield, while noticeable differences were found for yield and irrigation requirements of tomato. Under future scenarios, the production levels were reduced for tomato, whereas positive yield effects were observed for winter durum wheat. For winter durum wheat the simulation indicated that two- and three-year rotations, including one year of tomato cultivation, improved the cereal yield and this positive effect maintained its validity also in future scenarios. For both crops higher requirements of water and nitrogen were predicted under future scenarios. This result coupled with the decrease of yield caused negative reduction of water use efficiency and nitrogen use efficiency for tomato cultivation.

  3. 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...

  4. 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.

  5. 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

  6. 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

    2009-12-01

    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.

  7. DYNAMIC CROPPING SYSTEMS INFLUENCE ON SOIL BIOCHEMISTRY

    Science.gov (United States)

    In the Northern Great Plains, more intensive, diverse cropping systems have been developed as a means to improve soil and water conservation in the region. A no-till field research project was conducted near Mandan, ND on a Wilton-Temvik silt loam (fine-silty, mixed, superactive, frigid Pachic and T...

  8. 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.

  9. Reproduction of Pratylenchus penetrans on Potato and Crops Grown in Rotation with Potato

    OpenAIRE

    Florini, Diane A.; Loria, Rosemary

    1990-01-01

    The relative suitability of potato and crops frequently grown in rotation with potato as hosts for Pratylenchus penetrans was evaluated. Suitability of rye, wheat, corn, oat, sorgho-sudangrass, and potato were compared in pot studies based on ratios of final population : initial population density and densities of nematodes in roots at harvest. Population densities increased more on potato, oat, and corn than on rye, wheat, and sorgho-sudangrass. There were no differences among the four rye c...

  10. 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.

  11. 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.

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

    OpenAIRE

    Anisimova, Tatyana

    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.

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

    OpenAIRE

    Wilkins, R.J

    2007-01-01

    Eco-efficiency is concerned with the efficient and sustainable use of resources in farm production and land management. It can be increased either by altering the management of individual crop and livestock enterprises or by altering the land-use system. This paper concentrates on the effects of crop sequence and rotation on soil fertility and nutrient use efficiency. The potential importance of mixed farming involving both crops and livestock is stressed, particularly when the systems incorp...

  14. Characteristics of Nitrogen and Phosphorus Effluent Load from a Paddy-field District Implementing Crop Rotation

    Science.gov (United States)

    Hama, Takehide; Aoki, Takeru; Osuga, Katsuyuki; Nakamura, Kimihito; Sugiyama, Sho; Kawashima, Shigeto

    Implementation of collective crop rotation in a paddy-field district may increase nutrients effluent load. We have investigated a paddy-field district implementing collective crop rotation of wheat and soybeans, measured temporal variations in nutrients concentration of drainage water and the amount of discharged water for consecutive three years, and estimated nutrients effluent load from the district during the irrigation and non-irrigation periods. As a result, the highest concentration of nutrients was observed during the non-irrigation period in every investigation year. It was shown that high nutrients concentration of drainage water during the non-irrigation period was caused by runoff of fertilizer applied to wheat because the peaks of nutrients concentration of drainage water were seen in rainy days after fertilizer application in the crop-rotation field. The effluent load during the non-irrigation periods was 16.9-22.1 kgN ha-1 (nitrogen) and 0.84-1.42 kgP ha-1 (phosphorus), which respectively accounted for 46-66% and 27-54% of annual nutrients effluent load.

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

    OpenAIRE

    Slaats, J.J.P.

    1995-01-01

    In tropical Africa, traditional shifting cultivation can no longer provide sufficient food for the rapidly increasing population, whereas it threatens the remaining forests. An alternative is a fallow system based on the shrub Chromolaena odorata. Food crop cultivation in rotation with this fallow type in Ivory Coast was analysed and options for efficient and sustainable land use were identified. Farmers obtained 1.8 t ha -1maize without external inputs in a three-year fallow-cropping cycle. ...

  16. EUE (energy use ef?ciency) of cropping systems for a sustainable agriculture

    OpenAIRE

    Grignani, Carlo; Moretti, Barbara; Alluvione, Francesco; Sacco, Dario

    2011-01-01

    Energy ef?ciency of agriculture needs improvement to reduce the dependency on non-renewable energy sources. We estimated the energy ?ows of a wheatemaizeesoybeanemaize 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 ef?cient techniques to reduce energy...

  17. 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 bi...

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

    Science.gov (United States)

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

    2009-12-01

    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 biotechnology. Traditional breeding and selection, as well as the introduction of genes for improved growth and stress tolerance, have enabled high growth rates and improved site adaptability in trees grown for industrial applications. An example is the biotechnology-aided improvement of a highly productive tropical Eucalyptus hybrid, Eucalyptus grandis x Eucalyptus urophylla. This tree has acquired freeze tolerance by the introduction of a plant transcription factor that up-regulates the cold-response pathways and makes possible commercial plantings in the Southeastern United States. Transgenic trees with reduced lignin, modified lignin, or increased cellulose and hemicellulose will improve the efficiency of feedstock conversion into biofuels. Reduced lignin trees have been shown to improve efficiency in the pre-treatment step utilized in fermentation systems for biofuels production from lignocellulosics. For systems in which thermochemical or gasification approaches are utilized, increased density will be an important trait, while increased lignin might be a desired trait for direct firing or co-firing of wood for energy. Trees developed through biotechnology, like all transgenic plants, need to go through the regulatory process, which involves biosafety and risk assessment analyses prior to commercialization. PMID:19936031

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

    Energy Technology Data Exchange (ETDEWEB)

    Boehmel, Ute Constanze

    2007-07-18

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

  20. 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 which should be considered and accounted for in estimates and forecasts of agricultural greenhouse gas (GHG) emissions. 21 refs., 3 tabs., 10 figs

  1. Effect of changes in temperature and precipitation in Denmark on nitrate leaching in cereal cropping systems

    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.

  2. 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.

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

    Science.gov (United States)

    Sainju, Upendra M; Stevens, William B; Caesar-TonThat, Thecan; Liebig, Mark A; Wang, Jun

    2014-05-01

    Little information exists about how global warming potential (GWP) is affected by management practices in agroecosystems. We evaluated the effects of irrigation, tillage, crop rotation, and N fertilization on net GWP and greenhouse gas intensity (GHGI or GWP per unit crop yield) calculated by soil respiration (GWP and GHGI) and organic C (SOC) (GWP and GHGI) methods after accounting for CO emissions from all sources (irrigation, farm operations, N fertilization, and greenhouse gas [GHG] fluxes) and sinks (crop residue and SOC) in a Lihen sandy loam from 2008 to 2011 in western North Dakota. Treatments were two irrigation practices (irrigated vs. nonirrigated) and five cropping systems (conventional-till malt barley [ L.] with N fertilizer [CTBN], conventional-till malt barley with no N fertilizer [CTBO], no-till malt barley-pea [ L.] with N fertilizer [NTB-P], no-till malt barley with N fertilizer, and no-till malt barley with no N fertilizer [NTBO]). While CO equivalents were greater with irrigation, tillage, and N fertilization than without, NO and CH fluxes were 2 to 218 kg CO eq. ha greater in nonirrigated NTBN and irrigated CTBN than in other treatments. Previous year's crop residue and C sequestration rate were 202 to 9316 kg CO eq. ha greater in irrigated NTB-P than in other treatments. Compared with other treatments, GWP and GWP were 160 to 9052 kg CO eq. ha lower in irrigated and nonirrigated NTB-P. Similarly, GHGI and GHGI were lower in nonirrigated NTB-P than in other treatments. Regardless of irrigation practices, NTB-P may lower net GHG emissions more than other treatments in the northern Great Plains. PMID:25602807

  4. 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.

  5. 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

    2012-01-01

    One of the core ideas behind organic production is that cropping systems should be less dependent on import of resources, and minimize negative effects on the surrounding environment compared to conventional production. However, even when clearly complying with regulations for organic production, it is not always obvious that these goals are reached. As an example, strong dependence on import of manure is often seen in current organic production, especially in systems producing high value crops such as vegetable crops. The aim of the present study was to test novel approaches to organic 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 maincrop 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 differed strongly among crop species, but on average the organic crops yielded c. 82% of conventional yields in all three organic systems, when calculated based on the area actually grown with the main crops. In the O3 system some of the area of the vegetable fields was allocated to intercrops, so vegetable yields calculated based on total land area was only 63% of conventional yields. Differences in quality parameters of the harvested crops, i.e. nutrient content, dry matter content or damages by pests or diseases were fewand not systematic, whereas clear effects on nutrient balances and nitrogen leaching indicators were found. Root growth of all crops was studied in the C and O2 system, but only few effects of cropping system on root growth was observed. However, the addition of green manures to the systems almost doubled the average soil exploration by active root systems during the rotation from only 21% in C to 38% in O2 when measured to 2.4 m depth. This relates well to the observed differences in subsoil inorganic N content (Ninorg, 1–2 m depth) across the whole rotation (74 and 61 kg N ha-1 in C and O1 vs. only 22 and 21 kg N ha-1 in O2 and O3), indicating a strongly reduced N leaching loss in the two systems based on fertility building crops (green manures and catch crops). In short, the main distinctions were not observed between organic and conventional systems (i.e. C vs. O1, O2 and O3), but between systems based mainly on nutrient import vs. systems based mainly on fertility building crops (C and O1 vs. O2 and O3).

  6. Universal Entropy Bound for Rotating Systems

    OpenAIRE

    Hod, Shahar(The Ruppin Academic Center, Emeq Hefer, 40250, Israel)

    1999-01-01

    We conjecture a universal upper bound to the entropy of a rotating system. The entropy bound follows from application of the generalized second law of thermodynamics to an idealized gedanken experiment in which an entropy-bearing rotating system falls into a black hole. This bound is stronger than the Bekenstein entropy bound for non-rotating systems.

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

    Directory of Open Access Journals (Sweden)

    Marta K. Kostrzewska

    2012-10-01

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

  8. Refueling system with small diameter rotatable plugs

    International Nuclear Information System (INIS)

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

  9. Effects of cropping system and rates of nitrogen in animal slurry and mineral fertilizer on nitrate leaching from a sandy loam

    DEFF Research Database (Denmark)

    Thomsen, Ingrid Kaag; Hansen, JØrgen Frederik

    1993-01-01

    Leaching of nitrate from a sandy loam cropped with spring barley, winter wheat and grass was compared in a 4-year lysimeter study. Crops were grown continuously or in a sequence including sugarbeet. Lysimeters were unfertilized or supplied with equivalent amounts of inorganic nitrogen in calcium ammonium nitrate (CAN) or animal slurry according to recommended rates (1N) or 50% above recommended rates (1.5N). Compared with unfertilized crops, leaching of nitrate increased only slightly when 1N (CAN) was added. Successive annual additions of 1.5N (CAN) or IN and 1.5N (animal slurry) caused the cumulative loss of nitrate to increase significantly. More nitrate was leached after application of slurry because organic nitrogen in the slurry was mineralized. With IN (CAN) the leaching losses of nitrate were in the following order: continuous spring barley undersown with Italian ryegrass < continuous ley of perennial ryegrass < spring barley in rotation and undersown with grass < perennial ryegrass grown in rotation = winter wheat grown in rotation < sugarbeet in rotation < continuous winter wheat < continuous barley < bare fallow. At recommended levels of CAN (1N), cumulative nitrate losses over the four years were similar for the crops when grown in rotation or continuously. When crops received 1:5N (CAN) or animal slurry, nitrate losses from the crops grown continuously exceeded those from crops in rotation. Including a catch crop in the continuous cropping system eliminated the differences in nitrate leaching between the two cropping systems

  10. 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 (p<0.05) between cover crop and crop rotation for bulk density, gravimetric and total pore space in 2013. In addition, cover crop also significantly interacted (p<0.05) with tillage for bulk density and total pore space. All soil physical properties studied were significantly affected by the depth of sampling (p<0.0001), except for bulk density, the pore tortuosity factor and total pore space in 2012, and gravimetric and volumetric in 2013. Overall, soil physical properties were significantly affected by the treatments, with the effects changing from one year to another. Addition of a cover crop improved soil physical properties better in rotation than in monoculture.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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

    2015-03-01

    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.

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

    Science.gov (United States)

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

    2014-12-01

    The observed trends in the Midwestern United States of increasing rainfall variability will likely continue into the future. Events such as individual days of heavy rain as well as seasons of floods and droughts have large impacts on agricultural productivity and the natural resource base that underpins it. Such events lead to increased soil erosion, decreased water quality and reduced corn and soybean yields. Winter cover crops offer the potential to buffer many of these impacts because they essentially double the time for a living plant to protect and improve the soil. However, at present, cover crops are infrequently utilized in the Midwest (representing 1-2% of row cropped land cover) in particular due to producer concerns over higher costs and management, limited time and winter growing conditions as well as the potential harm to corn yields. In order to expand their use, there is a need to quantify how cover crops impact Midwest cropping systems in the long term and namely to understand how to optimize the benefits of cover crops while minimizing their impacts on cash crops. We are working with APSIM, a cropping systems platform, to specifically quantify the long term future impacts of cover crop incorporation in corn-based cropping systems. In general, our regional analysis showed only minor changes to corn and soybean yields (Project (CSCAP), a collaboration of eleven Midwestern institutions established to evaluate how conservation practices, including cover crops, improve the resilience of Midwest agriculture to future change. Such collaborations can help better quantify long term impacts of conservation practices on the landscape that ultimately lead to more climate-smart management of such agricultural systems.

  17. 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...

  18. 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)

  19. Increases of soil phosphatase and urease activities in potato fields by cropping rotation practices

    Science.gov (United States)

    Potato yield in Maine has remained relatively constant for over 50 years. To identify and quantify constraints to potato productivity, we established Status Quo (SQ), Soil Conserving (SC), Soil Improving (SI), Disease Suppressive (DS), and Continuous Potato (PP) cropping systems under both rainfed ...

  20. Nutrient management studies in biofuel cropping systems

    Science.gov (United States)

    Research was conducted to determine the effect of nutrient management practices on biofuel crop production, and to evaluate long term effects of biofuel crop production on selected chemical, physical and microbiological properties. Experimental plots for research on biofuel crop production were esta...

  1. 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.

  2. 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)

  3. 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.

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

    OpenAIRE

    Kayser, Manfred; Mu?ller, Ju?rgen; 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...

  5. Role of Nematodes, Nematicides, and Crop Rotation on the Productivity and Quality of Potato, Sweet Potato, Peanut, and Grain Sorghum

    OpenAIRE

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

    1996-01-01

    The objective of this experiment was to determine the effects of fenamiphos 15G and short-cycle potato (PO)-sweet potato (SP) grown continuously and in rotation with peanut (PE)-grain sorghum (GS) on yield, crop quality, and mixed nematode population densities of Meloidogyne arenaria, M. hapla, M. incognita, and Mesocriconema ornatum. Greater root-gall indices and damage by M. hapla and M. incognita occurred on potato than other crops. Most crop yields were higher and root-gall indices lower ...

  6. 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 sor making progress towards improving and sustaining wheat production system, helping with food security and poverty alleviation in Pakistan in the next few decades. (author)

  7. 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 res.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

  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. Global crop production forecasting data system analysis

    Science.gov (United States)

    Castruccio, P. A. (principal investigator); Loats, H. L.; Lloyd, D. G.

    1978-01-01

    The author has identified the following significant results. Findings led to the development of a theory of radiometric discrimination employing the mathematical framework of the theory of discrimination between scintillating radar targets. The theory indicated that the functions which drive accuracy of discrimination are the contrast ratio between targets, and the number of samples, or pixels, observed. Theoretical results led to three primary consequences, as regards the data system: (1) agricultural targets must be imaged at correctly chosen times, when the relative evolution of the crop's development is such as to maximize their contrast; (2) under these favorable conditions, the number of observed pixels can be significantly reduced with respect to wall-to-wall measurements; and (3) remotely sensed radiometric data must be suitably mixed with other auxiliary data, derived from external sources.

  10. 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.

  11. Soil Quality Indicators as Affected by a Long Term Barley-Maize and Maize Cropping Systems

    OpenAIRE

    Stefano Bocchi; Anna Corsini; Barbara Manachini

    2011-01-01

    Most soil studies aim a better characterization of the system through indicators. In the present study nematofauna and soil structure were chosen as indicators to be assess soil health as related to agricultural practices. The field research was carried out on the two fodder cropping systems continuous maize (CM, Zea mays L.) and a 3-year rotation of silage-maize – silage-barley (Hordeum vulgare L.) with Italian ryegrass (R3) and grain-maize maintained in these conditions for 18 yea...

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

    DEFF Research Database (Denmark)

    Chirinda, N.; 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.

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

    DEFF Research Database (Denmark)

    Chirinda, Ngonidzashe; 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 µg N m-2 d-1 at Flakkebjerg, and from 173 to 250 µg 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.

  14. 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...

  15. 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

    Scientific Electronic Library Online (English)

    Cesar Bauer, Gomes; Flávio Luiz Carpena, Carvalho; João Guilherme, Casagrande Júnior; Elizete Beatriz, Radmann.

    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 (FR Abstract in english In 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/ m [...] illet/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

  16. 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...

  17. 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...

  18. Work and energy in rotating systems

    CERN Document Server

    Manjarres, Diego A; Diaz, Rodolfo A

    2012-01-01

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

  19. Reducing Meloidogyne incognita Injury to Cucumber in a Tomato-Cucumber Double-Cropping System

    OpenAIRE

    Colyer, P. D.; Kirkpatrick, T. L.; Vernon, P. R.; Barham, J. D.; Bateman, R. J.

    1998-01-01

    The effects of a root-knot nematode-resistant tomato cultivar and application of the nematicide ethoprop on root-knot nematode injury to cucumber were compared in a tomato-cucumber double-cropping system. A root-knot nematode-resistant tomato cultivar, Celebrity, and a susceptible cultivar, Heatwave, were grown in rotation with cucumber in 1995 and 1996. Celebrity suppressed populations of Meloidogyne incognita in the soil and resulted in a low root-gall rating on the subsequent cucumber crop...

  20. 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.

  1. Axisymmetric Column Collapse in a Rotating System

    Science.gov (United States)

    Warnett, Jay; Thomas, Peter; Dennisenko, Petr

    2012-11-01

    We discuss experimental and computational results of a study investigating the collapse of an initially axisymmetric cylindrical column of granular material within a rotating environment of air or liquids. In industry this type of granular column collapse that is subject to background rotation is encountered, for instance, in the context of the spreading of powders and fertilizers. In comparison to its non-rotating counterpart the physical characteristics of the column collapse in a rotating system are expected to be modified by effects arising from centrifugal forces and Coriolis forces. We compare our new results for the rotating flow to data available in the literature for the collapse of granular columns in non-rotating systems to highlight the differences observed.

  2. Assessment of Carbon Sequestration in German Alley Cropping Systems

    Science.gov (United States)

    Tsonkova, P. B.; Quinkenstein, A.; Böhm, C.; Freese, D.

    2012-04-01

    Alley cropping systems (ACS) are agroforestry practices in which perennial trees or shrubs are grown in wide rows and arable crops are cultivated in the alleys between the tree rows. Recently, ACS which integrate stripes of short rotation coppices into conventional agricultural sites have gained interest in Germany. These systems can be used for simultaneous production of crops and woody biomass which enables farmers to diversify the provision of market goods. Adding trees into the agricultural landscape creates additional benefits for the farmer and society also known as ecosystem services. An ecosystem service provided by land use systems is carbon sequestration. The literature indicates that ACS are able to store more carbon compared to agriculture and their implementation may lead to greater benefits for the environment and society. Moreover, carbon sequestration in ACS could be included in carbon trading schemes and farmers rewarded additionally for the provision of this ecosystem service. However, methods are required which are easy to use and provide reliable information regarding change in carbon sequestration with change of the land use practice. In this context, our aim was to develop a methodology to assess carbon sequestration benefit provided by ACS in Germany. Therefore, the change of carbon in both soil and biomass had to be considered. To predict the change in soil carbon our methodology combined the 2006 IPCC Guidelines for National Greenhouse Gas Inventories and the soil organic carbon balance recommended by the Association of German Agricultural Investigation and Research Centers (VDLUFA). To reflect the change in biomass carbon average annual yields were adopted. The results showed that ACS established on agricultural sites can increase the carbon stored because in the new soil-plant system carbon content is higher compared to agriculture. ACS have been recommended as suitable land use systems for marginal sites, such as post-mining areas. In such areas soil carbon usually increases at a faster initial rate compared to agricultural land which means that these areas could provide high level of carbon sequestration service in the short term. The approach will be broadened to include assessment of other ecosystem services provided by ACS in Germany which would increase the possibility to adequately compensate farmers for the supply of environmental benefits. Keywords: agroforestry, biomass production, carbon sequestration, ecosystem services, marginal sites

  3. 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...

  4. Identification of greenhouse gas hot-spots and predicting district-wise GHG Intensities in rice based crop rotations in India using DNDC model

    Science.gov (United States)

    Yeluripati, J. B.; Frolking, S. E.; Li, C.; Nayak, D. R.; Adhya, T. K.

    2014-12-01

    Indian scientific research on rice cultivation has been targeted primarily at enhancing crop productivity for the wide range of soil and climate conditions across India. With the understanding that rice paddies are major source of atmospheric CH4 and N2O, there is a need for careful evaluation of the source strength of this ecosystem, and the influence of soil, water and crop management practices on both CH4 and N2O fluxes. A major challenge in meeting this objective lies in reducing the large uncertainties associated with regional and global level estimates of GHG emissions. Process-based biogeochemical models like DNDC (Denitrification and Decomposition model) can provide important insights into how agricultural management of rice paddies in?uences water resources, yields and greenhouse gas emissions. To quantify the CH4 and N2­O emissions from rice based crop rotations of India, DNDC model was modified, calibrated and evaluated at different sites across India. The observed N uptake, yields, CH4 and N2O emissions were in agreement with the values predicted by the model. To drive the model across India, a unique database was prepared combining soil/climate/landuse and management information. By linking the spatial database to DNDC, CH4 and N2O emissions from Indian rice based crop rotations for the rice growing season in the year 2000 were simulated on day-by-day basis. CH4 and N2O emissions from rice paddies in India from rice based-growing season were estimated to be 3.8 and 0.1 - 0.08 Tg (1 Tg = 1012 gm). Of the total CH4 emissions 30.6% (1.2 Tg) is emitted from single irrigated rice. 30.0% (1.1 Tg) and 14.46%(0.56 Tg) of total CH4 is emitted from double rice and single rainfed rice cropping system. 32.9% (33.16 Gg) of the total N2O emissions is emitted by upland rice followed by Single rainfed rice cropping system which emits about 19.9%(20.06 Gg) of total N2O . This paper presents a framework on GIS databases and a process-based biogeochemical model for estimation of greenhouse gas emissions from Indian based crop rotations.

  5. 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)

  6. Boundary layer control of rotating convection systems.

    Science.gov (United States)

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

    2009-01-15

    Turbulent rotating convection controls many observed features of stars and planets, such as magnetic fields, atmospheric jets and emitted heat flux patterns. It has long been argued that the influence of rotation on turbulent convection dynamics is governed by the ratio of the relevant global-scale forces: the Coriolis force and the buoyancy force. Here, however, we present results from laboratory and numerical experiments which exhibit transitions between rotationally dominated and non-rotating behaviour that are not determined by this global force balance. Instead, the transition is controlled by the relative thicknesses of the thermal (non-rotating) and Ekman (rotating) boundary layers. We formulate a predictive description of the transition between the two regimes on the basis of the competition between these two boundary layers. This transition scaling theory unifies the disparate results of an extensive array of previous experiments, and is broadly applicable to natural convection systems. PMID:19148097

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

    Science.gov (United States)

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

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

    Directory of Open Access Journals (Sweden)

    Francisco de Jesus Vernetti Junior

    2009-09-01

    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.The quantitative analysis with different types of indicators is crucial in determining the sustainability of crop succession. This study aimed to appraise that in tilled plain areas. The research was carried out in Pelotas, RS, Brazil at Embrapa Clima Temperado research area. The treatments consisted of successions of winter and spring-summer crops species for five years, followed by two years of fallow and three years of rice cropping. The spring-summer crops were corn and soybean, besides rice; the winter crops were cereals, leguminous pastures, mixtures species, turnip and native grass species. Seeding was performed either by no-till (NT or conventional (CT. The experiment was planned in a split-plot randomized blocks design with three replications, where the summer crops occupied the plots, while the winter's species were allocated to the subplots. The parameters measured were transformed into index to standardize the variables, each one in relation to the better measurement behavior, and arranged in four categories of analysis: (a Agronomics indices (dry weight and grain yield; (b Environmental indicators (soil fertility; (c Energy Indicators (gain and energy efficiency; d Economic Indicators (profitability and gross value of production. Through harmonic average rates calculated for each indicator, comparisons to the crop succession were then performed, and its sustainability inferred. Analyses of contrasts between the crop success

  9. A rotating target wheel system for Gammasphere

    Science.gov (United States)

    Greene, John P.; Falout, Joseph W.; Lister, Christopher J.; Nardi, Bruce G.; Fox, John D.

    1999-06-01

    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.

  10. Conversão e balanço energético de sistemas de rotação de culturas para triticale, sob plantio direto / Energy and balance conversion of crop rotation systems for triticale , under no-tillage

    Scientific Electronic Library Online (English)

    Henrique Pereira dos, Santos; João Carlos, Ignaczak; Julio Cesar Barreneche, Lhamby; Augusto Carlos, Baier.

    2000-03-01

    Full Text Available Na agricultura moderna, interessam sistemas de produção eficientes no uso da energia. Objetivou-se avaliar a conversão e o balanço energético de cinco sistemas de rotação de culturas envolvendo o triticale. Os sistemas avaliados, no período de 1987 a 1991, foram: I (triticale/soja), II (triticale/so [...] ja e aveia preta/soja), III (triticale/soja e ervilhaca/milho), IV (triticale/ soja, ervilhaca/milho e aveia preta/soja) e V (triticale/soja, triticale/soja, ervilhaca/milho e aveia preta/soja). Em 1990, nos sistemas II, IV e V, a aveia preta foi substituída por aveia branca. O experimento foi estabelecido em plantio direto, em delineamento de blocos ao acaso, com três repetições e parcelas com área útil de 24 m². Na média do período de 1987 a 1989, o sistema III apresentou conversão (9,30) e balanço energético (23.860 Mcal/ha) maiores do que os demais sistemas estudados (I: 5,38, II: 5,02, IV: 8,12 e V: 7,37; I: 18.067 Mcal/ha, II: 13.790 Mcal/ha, IV: 19.875 Mcal/ha e V: 19.264 Mcal/ha, respectivamente). Nesse período, as condições climáticas transcorreram normalmente. Na média do período de 1990 a 1991, não houve diferenças significativas entre as médias para conversão e para balanço energético. Nesse período, as condições climáticas foram adversas às culturas em estudo. Abstract in english Efficient energy conversion production systems are important for modern agriculture. The objetive was to evaluate the energy conversion and balance of five rotation systems that included triticale. The evaluated systems, from 1987 to 1991, were: I (triticale/soybean), II (triticale/soybean and black [...] oats/soybean), III (triticale/soybean and common vetch/corn), IV (triticale/soybean, common vetch/corn, and black oats/soybean), and V (triticale/soybean, triticale/soybean, common vetch/corn, and black oats/ soybean). In 1990, black oats was replaced by white oats in systems II, IV, and V. The experiment was set up under no-tillage, using a randomized block design with three replications and plots totalizing 24 m² . On average, for the period 1987 to 1989, system III showed higher energy conversou (9.30) and balance (23.860 Mcal/ha), as compared to the othen studied systems (I: 5.38, II: 5.02, IV: 8.12 e V: 7.37; I: 18.067 Mcal/ha, II: 13.790 Mcal/ha, IV: 19.875 Mcal/ha e V: 19.264 Mcal/ha, respectivily). In this period, the climatic conditions were normal. On average, the period 1990 to 1991, there were no significant differences between energy conversion and balance means. In this period, climatic conditions were adverse.

  11. Conversão e balanço energético de sistemas de rotação de culturas para triticale, sob plantio direto Energy and balance conversion of crop rotation systems for triticale , under no-tillage

    Directory of Open Access Journals (Sweden)

    Henrique Pereira dos Santos

    2000-03-01

    Full Text Available Na agricultura moderna, interessam sistemas de produção eficientes no uso da energia. Objetivou-se avaliar a conversão e o balanço energético de cinco sistemas de rotação de culturas envolvendo o triticale. Os sistemas avaliados, no período de 1987 a 1991, foram: I (triticale/soja, II (triticale/soja e aveia preta/soja, III (triticale/soja e ervilhaca/milho, IV (triticale/ soja, ervilhaca/milho e aveia preta/soja e V (triticale/soja, triticale/soja, ervilhaca/milho e aveia preta/soja. Em 1990, nos sistemas II, IV e V, a aveia preta foi substituída por aveia branca. O experimento foi estabelecido em plantio direto, em delineamento de blocos ao acaso, com três repetições e parcelas com área útil de 24 m². Na média do período de 1987 a 1989, o sistema III apresentou conversão (9,30 e balanço energético (23.860 Mcal/ha maiores do que os demais sistemas estudados (I: 5,38, II: 5,02, IV: 8,12 e V: 7,37; I: 18.067 Mcal/ha, II: 13.790 Mcal/ha, IV: 19.875 Mcal/ha e V: 19.264 Mcal/ha, respectivamente. Nesse período, as condições climáticas transcorreram normalmente. Na média do período de 1990 a 1991, não houve diferenças significativas entre as médias para conversão e para balanço energético. Nesse período, as condições climáticas foram adversas às culturas em estudo.Efficient energy conversion production systems are important for modern agriculture. The objetive was to evaluate the energy conversion and balance of five rotation systems that included triticale. The evaluated systems, from 1987 to 1991, were: I (triticale/soybean, II (triticale/soybean and black oats/soybean, III (triticale/soybean and common vetch/corn, IV (triticale/soybean, common vetch/corn, and black oats/soybean, and V (triticale/soybean, triticale/soybean, common vetch/corn, and black oats/ soybean. In 1990, black oats was replaced by white oats in systems II, IV, and V. The experiment was set up under no-tillage, using a randomized block design with three replications and plots totalizing 24 m² . On average, for the period 1987 to 1989, system III showed higher energy conversou (9.30 and balance (23.860 Mcal/ha, as compared to the othen studied systems (I: 5.38, II: 5.02, IV: 8.12 e V: 7.37; I: 18.067 Mcal/ha, II: 13.790 Mcal/ha, IV: 19.875 Mcal/ha e V: 19.264 Mcal/ha, respectivily. In this period, the climatic conditions were normal. On average, the period 1990 to 1991, there were no significant differences between energy conversion and balance means. In this period, climatic conditions were adverse.

  12. 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.

    1708-17-01

    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

  13. 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

  14. 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.

  15. 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.

  16. 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.

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

    DEFF Research Database (Denmark)

    Acharya, Bharat Sharma; Rasmussen, Jim

    2012-01-01

    Grasslands are potential carbon sinks to reduce unprecedented increase in atmospheric CO2. Effect of age (1–4-year-old) and management (slurry, grazing multispecies mixture) of a grass phase mixed crop rotation on carbon sequestration and emissions upon cultivation was compared with 17-year-old grassland and a pea field as reference. Aboveground and root biomass were determined and soils were incubated to study CO2 emissions after soil disturbance. Aboveground biomass was highest in 1-year-old grassland with slurry application and lowest in 4-year-old grassland without slurry application. Root biomass was highest in 4-year-old grassland, but all 1–4-year-old grasslands were in between the pea field (0.81 ± 0.094 g kg?1 soil) and the 17-year-old grassland (3.17 ± 0.22 g kg?1 soil). Grazed grasslands had significantly higher root biomass than cut grasslands. There was no significant difference in the CO2 emissions within 1–4-year-old grasslands. Only the 17-year-old grassland showed markedly higher CO2 emissions (4.9 ± 1.1 g CO2 kg?1 soil). Differences in aboveground and root biomass did not affect CO2 emissions, and slurry application did not either. The substantial increase in root biomass with age but indifference in CO2 emissions across the age and management in temporary grasslands, thus, indicates potential for long-term sequestration of soil C.

  18. 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.

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

    Directory of Open Access Journals (Sweden)

    Muli M. N.

    2015-01-01

    Full Text Available 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 manure, rock phosphate (RP and Farmyard manure (FYM combined with rock phosphate (RP+FYM. The study was conducted in Matuu Division, Kenya for two seasons; October 2012 to February 2013 short rain season (SRS and March to August 2013 long rain season (LRS. The experiment was laid out in a Randomized Complete Block design with a split-split plot arrangement and replicated three times. The main plots were tillage practices whereas the split plots were cropping systems and split-split plots were organic fertilizers and a control (nothing applied. The test crops were sorghum (Sorghum bicolor L. and sweet potato (Ipomea batatas L. lam rotated and/or intercropped with dolichos (Lablab purpureus and chickpea (Cicer arietinum. The CropSyst model was calibrated using measured soil texture, permanent wilting point, bulk density and initial soil moisture at the experimental site. Model validation was done using Root Mean Square Error (RMSE, percentage differences (PD and willmott index (WI of agreement. CropSyst model was reasonably validated as indicated by the low RMSE (0.5 to 1.3, PD (less than ±15 and WI index (close to 1. In the first season and second season, simulated soil moisture (101.91 and 108.3 mm was significantly (P < 0.05 high in sorghum/dolichos intercrop with RP+FYM application under tied ridges and least (13.52 and 15.4 mm in control treatment of sorghum mono crop under oxen plough. In sweet potato plots, both individual treatment and treatment interaction significantly influenced simulated soil moisture. Sweet potato-dolichos rotation (75.32 and 79.63 mm, with application of RP+FYM (75.03 and 79.39 mm under tield ridges (95 and 100.24 mm had highest simulated soil moisture levels under oxen plough (32.49 and 34.36 mm, sweet potato monocrop (53.46 and 55.26 mm and control (52.52 and 55.39 mm having the least during the first and second season, respectively. In both sorghum and sweet potato based cropping systems, soil moisture was correspondingly highest in tied ridges, intercropping and rotation systems involving dolichos and application of FYM+RP and least in control of monocropping under oxen plough. Information on effects of tillage practices, cropping systems and organic inputs could be very useful for soil water conservation purposes. Thus, using simulation models to attain the same could be the ultimate solution. A good agreement between observed and simulated soil moisture implied that CropSyst model is capable of investigating sustainable alternatives of increasing soil moisture in the ASALs.

  20. Collapse and relaxation of rotating stellar systems

    Science.gov (United States)

    Hohl, F.; Zang, T. A.

    1979-01-01

    The evolution of initially spherical, uniform-density, and uniform-velocity-dispersion stellar systems is investigated by means of a three-dimensional N-body computer model. Some 100,000 simulation stars are used to follow the collapse and relaxation of the system for various amounts of angular momentum in solid-body rotation. For initially low values of the angular momentum satisfying the Ostriker-Pebbles stability criterion the systems quickly relax to an axisymmetric shape and resemble elliptical galaxies in appearance. The maximum flattening for these systems is equivalent only to an E2 system. For larger values of the initial angular momentum bars develop, and the systems undergo a much more drastic evolution. The apparent rotational and random velocities of the barred systems are very sensitive to the viewing direction. An additional complication is the frequent misalignment of the apparent major axis with the direction that reflects the maximum rotation.

  1. 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.

  2. 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.

  3. Crop Diversification and Management System Influence Yield and Weeds in the Northern Great Plains

    Science.gov (United States)

    Available water, depleted soil quality, and weed competition are major constraints to dryland crop production in the northern Great Plains. We initiated a trial in 2004 comparing four crop rotations, with each rotational component in a two-by-two matrix of tillage (conventional vs. zero tillage) an...

  4. Simulation of nitrogen leaching from a fertigated crop rotation in a Mediterranean climate using the EU-Rotate_N and Hydrus-2D models

    DEFF Research Database (Denmark)

    Doltra, Jordi; Nuñoz, P

    2010-01-01

    Two different modeling approaches were used to simulate the N leached during an intensively fertigated crop rotation: a recently developed crop-based simulation model (EU-Rotate_N) and a widely recognized solute transport model (Hydrus-2D). Model performance was evaluated using data from an experiment where four N fertigation levels were applied to a bell pepper-cauliflower-Swiss chard rotation in a sandy loam soil. All the input data were obtained from measurements, transfer functions or were included in the model databases. Model runs were without specific site calibration. The use of soil input parameters based on the same pedotransfer functions in both models resulted in a very similar simulation of soil water content in spite of the different nature of the approaches. Good correlations were found between the simulated water draining below 60 cm and that calculated by water balance. 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 higher nitrate concentration in percolated water. Comparison of the observed and predicted yield response to N applications with EU-Rotate_N demonstrated that the best fertigation strategy could be identified and the risk of nitrate leaching quantified with this model. The results showed that for a successful solving of the problem studied, Hydrus-2D probably would need a more complex calibration, and that the EU-Rotate_N model can provide acceptable predictions by adjusting basic parameters for the growing conditions. Further research with other crops and soil types will allow up-scaling the quantification of N leaching from a field level to regional and national levels, identifying best management strategies in relation to N use from an environmental and economic perspective

  5. 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 mineralization. (Author) 35 refs., 3 tabs., 2 figs

  6. 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.

  7. 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...

  8. 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 desc

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

    Science.gov (United States)

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

    2015-01-01

    A field study was conducted to compare the formationand bacterial communities of rhizosheaths of wheat grown under wheat-cotton and wheat-rice rotation and to study the effects of bacterial inoculation on plant growth. Inoculation of Azospirillum sp. WS-1 and Bacillus sp. T-34 to wheat plants increased root length, root and shoot dry weight and dry weight of rhizosheathsoil when compared to non-inoculated control plants, and under both crop rotations. Comparing both crop rotations, root length, root and shoot dry weight and dry weight of soil attached with roots were higher under wheat-cotton rotation. Organic acids (citric acid, malic acid, acetic acid and oxalic acid) were detected in rhizosheaths from both rotations, with malic acid being most abundant with 24.8±2 and 21.3±1.5 ?g g-1 dry soil in wheat-cotton and wheat-rice rotation, respectively. Two sugars (sucrose, glucose) were detected in wheat rhizosheath under both rotations, with highest concentrations of sucrose (4.08±0.5 ?g g-1and 7.36±1.0 ?g g-1) and glucose (3.12±0.5 ?g g-1 and 3.01± ?g g-1) being detected in rhizosheaths of non-inoculated control plants under both rotations. Diversity of rhizosheath-associated bacteria was evaluated by cultivation, as well as by 454-pyrosequencing of PCR-tagged 16S rRNA gene amplicons. A total of 14 and 12 bacterial isolates predominantly belonging to the genera Arthrobacter, Azospirillum, Bacillus, Enterobacter and Pseudomonaswere obtained from the rhizosheath of wheat grown under wheat-cotton and wheat-rice rotation, respectively. Analysis of pyrosequencing data revealed Proteobacteria, Bacteriodetes and Verrucomicrobia as the most abundant phyla in wheat-rice rotation, whereas Actinobacteria, Firmicutes, Chloroflexi, Acidobacteria, Planctomycetes and Cyanobacteria were predominant in wheat-cotton rotation. From a total of 46,971 sequences, 10.9% showed ?97% similarity with 16S rRNA genes of 32 genera previously shown to include isolates with plant growth promoting activity (nitrogen fixation, phosphate-solubilization, IAA production). Among these, the most predominant genera were Arthrobacter, Azoarcus, Azospirillum, Bacillus, Cyanobacterium, Paenibacillus, Pseudomonas and Rhizobium. PMID:26121588

  10. Cowpea Crude Protein as Affected by Cropping System, Site and Nitrogen Fertilization

    Directory of Open Access Journals (Sweden)

    E. T. Sebetha

    2014-12-01

    Full Text Available High protein content in cowpea (Vigna unguiculata (L. Walp. is considered as major advantage for its use in nutritional components. In this way, an experiment was conducted to investigate the effect of cropping system, site, and nitrogen fertilization on cowpea crude protein. The study comprised of three cropping systems (Maize-cowpea rotation, monocropping cowpea and intercropped cowpea, three sites (Potchefstroom, Taung, and Rustenburg, South Africa and two rates of nitrogen fertilizers applied in kg ha-1 at each site (0 and 20 at Potchefstroom, 0 and 17 at Rustenburg, 0 and 23 at Taung. Moreover, a factorial experiment randomized in complete block design with three replications was conducted during 2011/12 and 2012/13 planting seasons. The protein content was determined from green leaves harvested before flowering, immature green pods and seeds during reproductive stage and maturity. Results showed that cropping system had significant effect on cowpea leaf protein content (P < 0.05. Intercropped cowpea significantly gave higher leaf protein (26.7% more content than rotational cowpea. Cowpea planted at Taung had significantly higher leaf protein (30.1% more content as compared to cowpea planted at other sites. Application of nitrogen fertilizer contributed to higher protein content of immature pods. Moreover, cowpea protein content differs among the different locations due to different soil types and climatic conditions.

  11. Rotation–Invariant Fingerprint Identification System

    Directory of Open Access Journals (Sweden)

    R. M.Mandi

    2012-07-01

    Full Text Available The fingerprint is the most widely used Biometric. The main focus of Intelligent Fingerprint Recognition System is to improve accuracy and efficiency.This system uses an algorithm for recovering translation parameters from two fingerprint images of the same individual that differ by Scaling, Rotation, and Transformation also known as similarity transformation or Rotation-scale-Translation (RST Transformation. This algorithm is very useful to identify two fingerprint images of the same individual which are misaligned by small transformations such as rotation or translation or scaling.The algorithm uses minutiae based matching to compare input fingerprint image with the template fingerprint image stored in the database. The algorithm uses various standard preprocessing steps. It includes all the stages to extract the minutiae. Maximum correlation between original and sensed image is found. The proposed system is tested on the pilot database.

  12. Using a cropping system model at regional scale: Low-data approaches for crop management information and model calibration

    OpenAIRE

    Therond, O.; Hengsdijk, H.; Casellas, E.; Wallach, D.; Adam, M. Y. O.; Belhouchette, H.; Oomen, R.; Russell, G.; Ewert, F.; Bergez, J. E.; Janssen, S. J. C.; Wery, J.; Ittersum, M. K.

    2011-01-01

    Cropping system models are powerful tools for regional impact assessment, but their input data requirements for large heterogeneous areas are difficult to fulfil. Hence, the objectives of this paper are to present low-data approaches for specifying detailed management data required by cropping system models, and for calibrating default crop parameters applied to 12 regions in the European Union (EU). Various downscaling and upscaling procedures for different data types are applied to address ...

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

    OpenAIRE

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

    2011-01-01

    Maize-based cropping systems (MBCSs), with different frequency of maize in the crop sequence, are common in European arable systems. Pesticide use differs according to the type of active ingredients and target organisms in different regions. Within the EU Network of Excellence ENDURE, two expert-based surveys were conducted focusing on four European study regions where experts were asked to identify MBCSs in their region, determine the current crop protection practices, propose advanced pract...

  14. 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.

  15. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-06-01

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

  17. Climate change impact on crop rotations of winter durum wheat and tomato in southern Italy: yield analysis and soil fertility

    OpenAIRE

    Annamaria Castrignanò; Donato Sollitto; Raffaele Lopez; Mirko Castellini; Luisa Giglio; Monia Charfeddine; Domenico Ventrella; Francesco Fornaro

    2012-01-01

    Cropping systems are affected by climate change because of the strong relationship between crop development, growth, yield, CO2 atmospheric concentration and climate conditions. The increasing temperatures and the reduction of available water resources may result in negative impacts on the agricultural activity in Mediterranean environments than other areas. In this study the CERES-Wheat and CROPGRO-Tomato models were used to assess the effects of climate change on winter wheat (Triticum duru...

  18. 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.

  19. Evaluación de la macrofauna del suelo en rotaciones cultivos-pasturas con laboreo convencional / Evaluation of soil macrofauna in crop-pasture rotations with conventional tillage

    Scientific Electronic Library Online (English)

    María Stella, ZERBINO.

    Full Text Available Los invertebrados que habitan el suelo son actores importantes en los procesos edáficos. La fauna edáfica comprende a organismos con tamaños y estrategias adaptativas diferentes. Los de mayor tamaño, constituyen la macrofauna (ancho del cuerpo mayor a 2 mm), que se destaca porque directa o indirecta [...] mente afectan las propiedades del suelo. Las comunidades presentes son la consecuencia de las prácticas de manejo de suelo que se realizan, por lo que tienen gran potencial de uso como indicadores. Este trabajo tuvo como objetivo evaluar el efecto de diferentes sistemas de rotación cultivos-pasturas sobre las comunidades de la macrofauna del suelo. Los tratamientos evaluados fueron: agricultura continua sin (S1) y con fertilización (S2), rotación agricultura 33% - pradera 66% (S4), rotación agricultura 50% - pradera 50% (S5), y rotación agricultura 66% - pradera 33% (S7). El número de individuos varió de acuerdo a la intensidad de los usos del suelo evaluados. Los tratamientos S1 y S4 tuvieron respectivamente, las menores y mayores densidades poblacionales de la mayoría de los taxones. El análisis de Co-Inercia entre las propiedades edáficas y la densidad fue significativo. El primer eje ordenó los usos del suelo de acuerdo a su intensidad. Los taxones Oligochaeta y Coleoptera adultos estuvieron asociados a S4, sistema con mayor cantidad de carbono orgánico y nitrógeno total. La evaluación de la macrofauna del suelo conjuntamente con las propiedades del mismo, es una herramienta útil para evaluar la sustentabilidad ambiental de los distintos usos del suelo. Abstract in english Soil-inhabiting invertebrates play an important role in soil processes. Soil fauna include organisms of diverse sizes and adaptive strategies. Macrofauna, large organisms with body width greater than 2 mm, influence soil properties, both directly and indirectly. Their communities are influenced by s [...] oil management and thus, have a great potential as bioindicators. The objective of this study was to evaluate the effect of different crop-pasture rotations on soil macrofauna. Treatments included continuous agriculture without (S1) and with (S2) fertilization, 33% crop - 66% pasture rotation (S4), 50% crop-pasture rotation (S5), and 66% crop - 33% pasture rotation (S7). The number of organisms collected varied with land use intensity; treatments S1 and S4 had the lowest and highest population densities for most taxa, respectively. The Co-Inertia analysis between soil properties and population density was significant. The first axis ordered land uses in relation to its intensity. Oligochaeta and Coleoptera adults were associated with S4, the system with highest organic carbon and total nitrogen contents. The evaluation of soil macrofauna together with soil properties is a useful tool to assess land use sustainability.

  20. 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

    2010-06-01

    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.

  1. 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.

  2. 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.

    1489-14-01

    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

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

    Directory of Open Access Journals (Sweden)

    Rodrigo Arroyo Garcia

    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 parcelas 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 superficiaisThe 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 (Urochloa 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

  4. Adiabatic plasma rotations in orthogonal coordinate systems

    Scientific Electronic Library Online (English)

    Ricardo L., Viana.

    2001-03-01

    Full Text Available An equation for MHD stationary equilibrium of rotating plasmas in the azimuthal direction is derived in the case of an orthogonal curvilinear coordinate system. The basic assumptions we made are: (i) there is an ignorable coordinate so that surface quantities are independent of it; (ii) the entropy [...] is a surface quantity.

  5. Potassium Nutrition In Ratoon Sugarcane Under A Conservation Cropping System

    Scientific Electronic Library Online (English)

    Rilner, Alves Flores; Renato, De Mello Prado; Hilário, Júnior De Almeida; Márcio Alexandre, Pancelli; Jonas Pereira, De Souza Junior; Anelisa, De Aquino Vidal Lacerda Soares.

    2014-06-01

    Full Text Available Ratoon sugarcane response to potassium is dependent on the environmental conditions of the region. Cropping systems that do not burn crop biomass after harvest leave crop residues on the soil, affecting the soil-plant nutrient dynamics system and fertilizer requirements. The objective of this study [...] was to evaluate the effect of potassium fertilization of first and second ratoon sugarcane crops on potassium contents in the soil, in the plant, and yield and quality of stalksin an Oxisol under a conservation cropping system. The following potassium rates were tested: 0, 27, 54, 108, and 162 kg K ha-1, arranged in a randomized block design with five replicates. The application of potassium increased soil nutrient concentrations at six months, reaching 2.87 and 2.61 mmol c dm-3 with the highest rate in the first and second ratoons, respectively. The increase in available exchangeable-K content in the soil favored a greater plant uptake of this nutrient, reaching 12.1 and 10.0 g kg-1 in the first and second ratoons, respectively. The increase in potassium absorption by plants was reflected in the production of stems; the highest yields (87.0 and 132.9 t ha-1) were obtained with the application of 162 kg K ha-1 in the first and second ratoons, respectively.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. Evaluation of the ECOSSE model for simulating soil carbon under short rotation forestry energy crops in Britain

    OpenAIRE

    Dondini, Marta; Jones, Edward O.; Richards, Mark; Pogson, Mark; Rowe, Rebecca L.; Keith, Aidan M; Perks, Mike P.; McNamara, Niall P.; Smith, Joanne U.; Smith, Pete

    2015-01-01

    Understanding and predicting the effects of land-use change to short rotation forestry (SRF) on soil C is an important requirement for fully assessing the C mitigation potential of SRF as a bioenergy crop. There is little current knowledge of SRF in the UK and in particular a lack of consistent measured datasets on the direct impacts of land use change on soil C stocks. The ECOSSE model was developed to simulate soil C dynamics and greenhouse gas (GHG) emissions in mineral and organic so...

  11. Arable habitat use by wood mice (Apodemus sylvaticus). 3. A farm-scale experiment on the effects of crop rotation

    OpenAIRE

    MacDonald, DW; Tew, TE; Todd, IA; Garner, JP; Johnson, PJ

    2000-01-01

    We investigated the effects of crop type on numbers and movements of wood mice Apodemus sylvaticus in field edges and in arable fields containing either winter wheat, winter barley or oil-seed rape, grown on a 3-year rotation. We also investigated the effect of habitat (field centre vs edge), and of season and year. This was done at the individual level using radio-tracking, and at the population level using live-trapping. Wood mouse population size (estimated as minimum number alive) was sig...

  12. Dynamical flexibilities of mechanical rotational systems

    Directory of Open Access Journals (Sweden)

    S. ?ó?kiewski

    2008-12-01

    Full Text Available Purpose: of this work is to present dynamical flexibilities of rotational beams and rods systems. The results ofmathematical calculations were presented in the form of dynamical flexibility of analyzed systems. In final solutionthere were took into consideration the interactions between the major motions and local vibrations of subsystems.Design/methodology/approach: The dynamical flexibilities were derived by the Galerkin’s method. The dynamicalflexibilities for example numerical cases were presented onto charts of attenuation-frequency characteristics. Themathematical models were derived on the basis of known equations of motion derived in previous thesis’s.Findings: After analysis of characteristics we can observe the transportation effect. We can notice additional poleson the characteristic of dynamical flexibility characteristics and after increasing angular velocity created modessymmetrically propagate from the origin mode and instead of the original mode there is created a zero’s amplitude.Research limitations/implications: Analyzed systems are beams and rods in rotational motion. Motion waslimited to plane motion. Future works will be connected with consideration of complex systems.Practical implications: of derived dynamical flexibilities of free-free and fixed beams and rods systems is apossibility of derivation of the stability zones of analyzed systems and derivation of eigenfrequencies and zerosin the function of angular velocity of work motion.Originality/value: Models analyzed in this thesis apply to rotating rod and beam systems with taking intoconsideration the transportation effect. This new approach of analyzing rod and beam systems can be put to usein modelling, analyzing and designing machines and mechanisms with rotational elements.

  13. 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.

  14. Efecto de la rotación de cultivos y prácticas de labranza sobre las fracciones de la materia orgánica del suelo / TILLAGE SYSTEM AND CROP ROTATION EFFECTS ON SOIL ORGANIC MATTER FRACTIONS / EFEITO DA ROTAÇÃO DE CULTIVOS E PRÁTICAS DE LAVRAGEM SOBRE AS FRAÇÕES DA MATÉRIA ORGÂNICA DO SOLO

    Scientific Electronic Library Online (English)

    Yusmary, Espinoza; Zenaida, Lozano; Lorenzo, Velásquez.

    2007-08-01

    Full Text Available As práticas de lavragem e rotação de cultivos podem modificar a matéria orgânica do solo (MOS). Um estudo conduzido por sete anos, onde se incluíram lavragem e rotação de cultivos, foi utilizado para avaliar o efeito do manejo do solo sobre as diferentes frações do C e N. O experimento foi localizad [...] o em Turén, estado Portuguesa, Venezuela, e incluiu dois sistemas de lavragem, lavragem convencional (LC) e semeadura direta (SD), e duas rotações de cultivos, milho-algodão (MA) e milho-feijão (MF). Amostras de solo foram coletadas a três profundidades e se analisou o C (COT) e N orgânico total (NOT), C (MMC) e N (MMN) da massa microbiana, C e N mineralizável (Cmin e Nmin), N lábil potencialmente mineralizável (N1) e sua taxa de decomposição (kl). As mudanças observadas em COS e NOS em resposta à lavragem e à rotação de cultivos foram relacionadas com a quantidade e qualidade de resíduos de plantas que retornam ao solo, mas não com a sua distribuição no perfil do solo, com exceção da MO mineralizável. Este estudo demonstra a importância da MMC, MMN e da mineralização do C e N como índices para conhecer a dinâmica da MOS em uma zona tropical. Por outra parte, o N1 pode ser usado como indicador da capacidade do solo de liberar N da MOS. Abstract in spanish Las prácticas de labranza y rotación de cultivos pueden modificar la materia orgánica del suelo (MOS). Un estudio conducido por siete años, donde se incluyeron labranza y rotación de cultivos, fue utilizado para evaluar el efecto del manejo de suelo sobre las diferentes fracciones de C y N. El exper [...] imento fue localizado en Turén, estado Portuguesa, Venezuela, e incluyó dos sistemas de labranza, labranza convencional (LC) y siembra directa (SD), y dos rotaciones de cultivos, maíz-algodón (MA) y maíz-fríjol (MF). Muestras de suelo fueron colectadas a tres profundidades y se analizó el C (COT) y N orgánico total (NOT), C (MMC) y N (MMN) de la masa microbiana, C y N mineralizable (Cmin y Nmin), N lábil potencialmente mineralizable (N1) y su tasa de descomposición (k l). Los cambios observados en COT y NOT en respuesta a la labranza y a la rotación de cultivos fueron relacionados con la cantidad y calidad de residuos de planta que regresan al suelo, pero no con su distribución en el perfil del suelo, con excepción de la MO mineralizable. Este estudio demuestra la importancia de la MMC, MMN y de la mineralización de C y N como índices para conocer la dinámica de la MOS en una zona tropical. Por otra parte, el N1 puede ser usado como indicador de la capacidad del suelo de liberar N de la MOS. Abstract in english Cultivation practices such as tillage and crop rotation can modify soil organic matter (MOS). A crop rotation-tillage study was conducted for seven years in order to evaluate the effects on the different pools of C and N. The experiment was located in Turén, Portuguesa State, Venezuela, with two til [...] lage systems: conventional tillage (CT), and no tillage (NT) and two crop rotations, corn-cotton (CC), and corn-bean (CB). Soil samples were collected at three depths and analyzed for total organic C (COT) and N (TON), microbial biomass C (MMC) and N (MMN), mineralized C and N (Cmin and Nmin), and potentially mineralized labile N (N1) and its decay rate (k l). The changes observed in COT and NOT in response to tillage and rotation were related to the quantity and quality of plant residues returned to the soil, but not to their distribution in the soil profile, with exception of MO mineralization. This study shows the importance of the MMC, MMN, C and N mineralization as indexes of MOS dynamics in a tropical region. On the other hand, N1 can be used as an indicator of the relative soil capacity to release N from MOS.

  15. Modeling long-term dynamics of carbon and nitrogen in intensive rice-based cropping systems in the Indo-Gangetic Plains (India)

    OpenAIRE

    Shibu, M.E.

    2007-01-01

    Soil organic matter (SOM) is an essential component of any sustainable crop production system, both as a nutrient source for the crop and a physical conditioner for the soil. Land use systems based on (flooded) rice- aerobic upland crop rotations, with their annual cycles of wet and dry soil conditions, puddling and plowing, are unique in their influence on SOM dynamics. Recent reports have related yield 'stagnation' in rice-wheat systems in parts of the Indo-Gangetic Plains (IGP) to a declin...

  16. Soil organisms in organic and conventional cropping systems

    Directory of Open Access Journals (Sweden)

    Bettiol Wagner

    2002-01-01

    Full Text Available Despite the recent interest in organic agriculture, little research has been carried out in this area. Thus, the objective of this study was to compare, in a dystrophic Ultisol, the effects of organic and conventional agricultures on soil organism populations, for the tomato (Lycopersicum esculentum and corn (Zea mays crops. In general, it was found that fungus, bacterium and actinomycet populations counted by the number of colonies in the media, were similar for the two cropping systems. CO2 evolution during the cropping season was higher, up to the double for the organic agriculture system as compared to the conventional. The number of earthworms was about ten times higher in the organic system. There was no difference in the decomposition rate of organic matter of the two systems. In general, the number of microartropods was always higher in the organic plots in relation to the conventional ones, reflectining on the Shannon index diversity. The higher insect population belonged to the Collembola order, and in the case of mites, to the superfamily Oribatuloidea. Individuals of the groups Aranae, Chilopoda, Dyplopoda, Pauropoda, Protura and Symphyla were occasionally collected in similar number in both cropping systems.

  17. 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.

  18. 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...

  19. Present and potential weed infestation of spring cereals in different cropping system

    Directory of Open Access Journals (Sweden)

    Andrzej Weso?owski

    2001-06-01

    Full Text Available This paper presents the results of investigations on the weed infestation and vertical distribution of weed seed bank in rendzina under spring cereals cultivation in crop rotations and monoculture. Used herbicides (MCPA and fenoxaprop-P-etylu decreased the number of weeds and species composition in comparison with harrowing. In the soil layer of 0-25 cm used in the monoculture there was found about 22,9% weed seeds more than in crop rotation. In the canopy of spring cereals the following weeds dominated: in crop rotation - Chenopodium album, Echinochloa crus-galli and Veronica persica; and in monoculture - Stellaria media, Galium aparine and Chenopodium album. In the soil layer of 0-25 cm used in crop rotation and monoculture the following weed seeds dominated : Amaranthus retroflexus, Chenopodium album and Stellaria media.

  20. 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 dsuming 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

  1. 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.

  2. PEARL MILLET AS A ROTATION CROP FOR REDUCING NEMATODES AND SOIL-BORNE DISEASES IN PEANUT

    Science.gov (United States)

    Our objective was to determine the effects of pearl millet on root-knot nematodes (Meloidogyne arenaria), stem rot, and Rhizoctonia limb rot when planted in rotation with peanut. The experiment was conducted in a field naturally infested with the nematode. Peanut was rotated with either two years ...

  3. 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)

  4. 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)

  5. System design description for the HMT Rotation Motor Heater System

    International Nuclear Information System (INIS)

    This document is the design description for the Rotation Motor Heater System on waste tank 241-SY-101. The description includes the certified vendor (CV) file number, operators instructions, and heater sizing calculations

  6. 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 dif...

  7. Use of SPOT-VEGETATION in different versions of the European crop growth monitoring system

    OpenAIRE

    Piccard, I.; Eerens, H.; Oger, Robert; Curnel, Y.; Tychon, Bernard; Ozer; Diepen, K.

    2005-01-01

    The Crop Growth Monitoring System (CGMS) is a GIS-application, developed and operated since 1989 by the MARS-unit of the EU Joint Research Centre. The primary objective is the timely forecasting of the yields of the main crops on the Pan-European continent.To reach this goal, CGMS combines all available (historical and actual) resources: official crop statistics, daily meteorological data, specific crop and soil parameters, the predictions of the (spatialized) crop growth model WOFOST, and th...

  8. Use of spot/vegetation in different versions of the European crop growth monitoring system.

    OpenAIRE

    Piccard, I.; Eerens, H.; Oger, Robert; Curnel, Y.; Tychon, Bernard; Ozer; Van Diepen, K.

    2005-01-01

    The Crop Growth Monitoring System (CGMS) is a GIS-application, developed and operated since 1989 by the MARS-unit of the EU Joint Research Centre. The primary objective is the timely forecasting of the yields of the main crops on the Pan-European continent.To reach this goal, CGMS combines all available (historical and actual) resources: official crop statistics, daily meteorological data, specific crop and soil parameters, the predictions of the (spatialized) crop growth model WOFOST, and th...

  9. 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

  10. 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.

  11. [CO2 emission from soil-crop system as influenced by crop growth and tissue N content].

    Science.gov (United States)

    Sun, Wen-juan; Huang, Yao; Chen, Shu-tao; Yang, Zhao-fang; Zheng, Xun-hua

    2004-05-01

    To understand the CO2 emission from soil-crop system as influenced by crop growth and tissue N content, pot and field experiments were carried out during 2001-02 wheat and rice growing seasons. Black chambers were used to take gas samples within a closed soil-crop system. The CO2 emission rate was detected by a gas chromatograph. Seasonal change of the CO2 emission was observed from the soil-crop system. Respiration from the soil-rice system was higher than that from the soil-wheat system. Dark respiration of the crop shoot was positively correlated to the shoot biomass. The respiration coefficient Rd, defined as the amount of CO2-C respired by per unit biomass C within one day under a reference temperature of 25 degrees C, can be well quantitatively expressed by shoot N content for either wheat or rice crop. Relationship between the Rd and the N content can be described as a linear regression of Rd = 0.0124N - 0.0076 (R2=0.9879, pequation of Rd = 0.0085N2 - 0.0049N (R2=0.9776, p<0.001) for the rice crop, respectively. The crop roots promoted the soil respiration greatly, which increased by 178% for the wheat and 338% for the rice in comparison with the respiration from root-free soil. A further calculation of the root respiration, including root autotrophic respiration and rhizosphere respiration, suggested that the contribution of crop rhizosphere respiration to the total soil respiration was greater in the upland soil than that in the irrigated paddy soil. PMID:15327243

  12. 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.

  13. Long-term rice-based cropping system effects on near-surface soil compaction

    Directory of Open Access Journals (Sweden)

    Kristofor R. Brye

    2011-05-01

    Full Text Available Irrigated rice (Oryza sativa L. production is as-sociated with frequent cycling between anaero-bic and aerobic conditions, which can lead to a greater rate of soil organic matter (SOM de-composition, thus potentially increasing soil bulk density (BD over time. A study was con-ducted in the Mississippi River Delta region of eastern Arkansas, USA to evaluate the long-term effects of rice-based crop rotations, tillage [conventional tillage (CT and no-tillage (NT], soil fertility regime (optimal and sub-optimal, and soil depth (0-10 and 10-20 cm after 10 years of consistent management on near-surface soil compaction, as measured by BD. Soil BD was greater under NT than CT in the top 10 cm, but was similar between NT and CT in the 10- to 20-cm depth interval. Soil BD differed among common rice-based cropping systems with corn, soybean, and winter wheat, but few consistent trends were evident. It appears that, even after 10 years of continuous CT or NT rice production on a silt-loam soil, substantially increased near-surface soil BD has not occurred to the point where soil compaction would be a likely culprit responsible for a reduced early season stand establishment or crop yield differences among rice-based copping systems.

  14. Quantum Rotational Effects in Nanomagnetic Systems

    Science.gov (United States)

    O'Keeffe, Michael F.

    Quantum tunneling of the magnetic moment in a nanomagnet must conserve the total angular momentum. For a nanomagnet embedded in a rigid body, reversal of the magnetic moment will cause the body to rotate as a whole. When embedded in an elastic environment, tunneling of the magnetic moment will cause local elastic twists of the crystal structure. In this thesis, I will present a theoretical study of the interplay between magnetization and rotations in a variety of nanomagnetic systems which have some degree of rotational freedom. We investigate the effect of rotational freedom on the tunnel splitting of a nanomagnet which is free to rotate about its easy axis. Calculating the exact instanton of the coupled equations of motion shows that mechanical freedom of the particle renormalizes the easy axis anisotropy, increasing the tunnel splitting. To understand magnetization dynamics in free particles, we study a quantum mechanical model of a tunneling spin embedded in a rigid rotor. The exact energy levels for a symmetric rotor exhibit first and second order quantum phase transitions between states with different values the magnetic moment. A quantum phase diagram is obtained in which the magnetic moment depends strongly on the moments of inertia. An intrinsic contribution to decoherence of current oscillations of a flux qubit must come from the angular momentum it transfers to the surrounding body. Within exactly solvable models of a qubit embedded in a rigid body and an elastic medium, we show that slow decoherence is permitted if the solid is macroscopically large. The spin-boson model is one of the simplest representations of a two-level system interacting with a quantum harmonic oscillator, yet has eluded a closed-form solution. I investigate some possible approaches to understanding its spectrum. The Landau-Zener dynamics of a tunneling spin coupled to a torsional resonator show that for certain parameter ranges the system exhibits multiple Landau-Zener transitions. These transitions coincide in time with changes in the oscillator dynamics. A large number of spins on a single oscillator coupled only through the in-phase oscillations behaves as a single large spin, greatly enhancing the spin-phonon coupling.

  15. Qualidade fisiológica de sementes de soja cultivada em rotação com milheto / Seed quality of soybean cropped in rotation with pearl-millet

    Scientific Electronic Library Online (English)

    João, Nakagawa; Leandro Borges, Lemos; Cláudio, Cavariani; Fernando Guido, Penariol.

    2006-04-01

    Full Text Available Para o sucesso do plantio direto há necessidade de que a cultura antecessora à principal seja boa produtora e mantenedora de cobertura vegetal. O milheto tem-se constituído em boa opção de cultivo no outono/inverno para rotação com soja, porém não há estudos avaliando o efeito do sistema na qualidad [...] e das sementes. O objetivo do trabalho foi estudar o efeito de três épocas de semeadura e cinco manejos com ceifas do milheto sobre a qualidade fisiológica de sementes de soja cultivada em sucessão, por plantio direto, na mesma área, por três ciclos de rotação (1999/2000; 2001/2002 e 2002/2003). As épocas de semeadura constituíram três experimentos (E1, E2 e E3), em delineamento experimental de blocos ao acaso com cinco tratamentos (M1 = ceifa a cada florescimento e retirada da massa vegetal; M2 = ceifa a cada florescimento e permanência da massa vegetal; M3 = ceifa no florescimento e retirada da massa vegetal; M4 = ceifa no florescimento e permanência da massa vegetal e M5 = sem ceifa até a produção de grãos, quando foi cortada a panícula, permanecendo o restante da massa vegetal), e quatro repetições. Os experimentos de milheto foram semeados em 1999: E1 = 05/03, E2 = 25/03 e E3 = 19/04; em 2001 = E1 = 17/04, E2 = 07/05 e E3 = 27/05, e em 2002: E1 = 25/04, E2 = 15/05 e E3. = 05/06. Em cada ciclo de rotação, a soja foi implantada nos três experimentos na mesma data após o manejo final do milheto com dessecação química; as colheitas foram realizadas na mesma data, também. As sementes de soja, cv. Embrapa-48, foram avaliadas quanto ao tamanho, massa de 100 sementes, teor de água, germinação e vigor. Sementes de soja com melhor qualidade fisiológica foram obtidas, nos três ciclos de sucessão, quando cultivada após a primeira época de semeadura do milheto, independentemente do manejo com ceifas do milheto, cujo efeito foi pouco evidente. Abstract in english A successful no-tillage system requires high mass production in the preceding to the main crop that and its crop residues remain in the soil. Pearl-millet was shown to be a good option as an autumn-winter crop before soybean, in rotation, but there are no studies of this system on soybean seed quali [...] ty. The effects were investigated of three sowing times and five types of crop cut management of pearl-millet on seed quality of soybean cropped in sucession, in no-tillage system, for three crop rotation cycles (1999-2000, 2001-2002 and 2002-2003). Each pearl-millet sowing time was a trial with five treatments (M1 = cut at each flowering and no residues; M2 = cut at each flowering with residues; M3 cut at flowering and no residues; M4 = cut at flowering with residues; M5 = not cut until mature panicle harvest, then with residues) and four replications, arranged in randomized blocks. The pearl-millet trials were sown in 1999: E1 = 5 March, E2 = 25 March and E3 = 19 April; in 2001: E1 = 17 April, E2 = 7 May and E3 = 27 May; and in 2002: E1 = 25 April, E2 = 15 May and E3 = 05 June. The soybean was sown at the same time for the three trials in each crop rotation cycle, after chemical dessecation of the pearl-millet; the soybean was also harvested at the same time. The soybean seeds, cv. Embrapa-48, were evaluated by its size, weight of 100 seeds, water content, germination and vigor. Soybean seeds with better physiological quality were obtained when cropped in sucession on residues of the first pearl-millet sowing for three cycles of crops rotation, regardless of the pearl millet harvest management, whose effect was not clear.

  16. Nematode Numbers and Crop Yield in a Fenamiphos-Treated Sweet Corn-Sweet Potato-Vetch Cropping System

    OpenAIRE

    Johnson, A. W.; Dowler, C. C.; Glaze, N. C.; Chalfant, R. B.; Golden, A. M.

    1992-01-01

    Nematode population densities and yield of sweet corn and sweet potato as affected by the nematicide fenamiphos, in a sweet corn-sweet potato-vetch cropping system, were determined in a 5-year test (1981-85). Sweet potato was the best host of Meloidogyne incognita of these three crops. Fenamiphos 15G (6.7 kg a.i./ha) incorporated broadcast in the top 15 cm of the soil layer before planting of each crop increased (P ? 0.05) yields of sweet corn in 1981 and 1982 and sweet potato number 1 grad...

  17. 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)

  18. 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 ...

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

    Directory of Open Access Journals (Sweden)

    Teodor RUSU

    2006-05-01

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

  20. Cropping Systems to Improve Carbon Sequestration for Mitigation of Climate Change

    Directory of Open Access Journals (Sweden)

    Qingren Wang

    2010-09-01

    Full Text Available The recent trend of an increase in the concentration of greenhouse gases (GHGs in the atmosphere has led to an ele-vated concern and urgency to adopt measures for carbon (C sequestration to mitigate the climate change. Among all GHGs, carbon dioxide (CO2 is the most important one which occurs in the greatest concentration and has the strong-est radiative forcing among all. Reducing the release of CO2 to the atmosphere through “green energy” technologies or fossil fuel energy alternatives, such as wind, solar and hydraulic energies, is a major challenge. However, removal of atmospheric CO2 by terrestrial ecosystems via C sequestration and converting the sequestered C into the soil organic C has provided a great opportunity for shifting GHG emission to mitigate the climate change. Soil is an ideal reservoir for storage of organic C since soil organic C has been depleted due to land misuse and inappropriate management through the long history. To optimize the efficiency of C sequestration in agriculture, cropping systems, such as crop rotation, intercropping, cover cropping, etc., play a critical role by influencing optimal yield, total increased C sequestered with biomass, and that remained in the soil. As matter of fact, soil C sequestration is a multiple purpose strategy. It restores degraded soils, enhances the land productivity, improves the diversity, protects the environment and reduces the enrichment of atmospheric CO2, hence shifts emission of GHGs and mitigates climate change.

  1. 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.

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

    Science.gov (United States)

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

  3. 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...

  4. 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).

  5. Vibration diagnostic system for rotating machinery

    International Nuclear Information System (INIS)

    A new system has been developed for early detecting and analyzing mechanical abnormalities occuring in motors and pumps in nuclear power plants. It is so designed as to detect and diagnose the abnormalities by monitoring and analyzing the vibration of rotating machines. Sham examinations were performed on vertical pumps and horizontal volute pumps. Abnormalities assumed to occur practically were intentionally given to the machines; the relation between the abnormality and failures and their specific features were investigated; the results were reflected upon the algorithm for abnormality diagnosis. With the system manufactured in trial, tests were made on a pump constructed for experiments, and reliability tests were made at an actual plant. A firm belief on its practicability has been established. (author)

  6. Nitrogen balance and groundwater nitrate contamination: Comparison among three intensive cropping systems on the North China Plain

    International Nuclear Information System (INIS)

    The annual nitrogen (N) budget and groundwater nitrate-N concentrations were studied in the field in three major intensive cropping systems in Shandong province, north China. In the greenhouse vegetable systems the annual N inputs from fertilizers, manures and irrigation water were 1358, 1881 and 402 kg N ha-1 on average, representing 2.5, 37.5 and 83.8 times the corresponding values in wheat (Triticum aestivum L.)-maize (Zea mays L.) rotations and 2.1, 10.4 and 68.2 times the values in apple (Malus pumila Mill.) orchards. The N surplus values were 349, 3327 and 746 kg N ha-1, with residual soil nitrate-N after harvest amounting to 221-275, 1173 and 613 kg N ha-1 in the top 90 cm of the soil profile and 213-242, 1032 and 976 kg N ha-1 at 90-180 cm depth in wheat-maize, greenhouse vegetable and orchard systems, respectively. Nitrate leaching was evident in all three cropping systems and the groundwater in shallow wells (<15 m depth) was heavily contaminated in the greenhouse vegetable production area, where total N inputs were much higher than crop requirements and the excessive fertilizer N inputs were only about 40% of total N inputs. - Intensive greenhouse vegetable production systems may pose a greater nitrogen pollution threat than apple orchards or cereal rotations to soil and water quality in north China

  7. Black Locust (Robinia Pseudoacacia L.) short-rotation energy crops in Hungary: a review

    OpenAIRE

    Rédei, Károly; VEPERDI, Irina; Tomé, Margarida; Soares, Paula

    2010-01-01

    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 e...

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

    OpenAIRE

    Rédei, Károly; CSIHA, Imre; KESER?, Zsolt

    2011-01-01

    The improvement of the reliability of renewable resources and the decline in reserves offossile raw material in the coming decades will lead to increasing demands for wood material andconsequently to a greater role of short rotation forestry (SRF). Particular efforts have been made inEurope to substitute fossils with renewables, in this context the proportion of renewable energy shouldbe increased to 20% by 2020. SRF can be provide relatively high dendromass (biomass) incrementrates if the sh...

  9. 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.

  10. Integrated soil–crop system management for food security

    OpenAIRE

    Chen, Xin-ping; Cui, Zhen-ling; Vitousek, Peter M.; Cassman, Kenneth G.; Matson, Pamela A.; Bai, Jin-shun; Meng, Qing-feng; Hou, Peng; Yue, Shan-chao; Ro?mheld, Volker; Zhang, Fu-suo

    2011-01-01

    China and other rapidly developing economies face the dual challenge of substantially increasing yields of cereal grains while at the same time reducing the very substantial environmental impacts of intensive agriculture. We used a model-driven integrated soil–crop system management approach to develop a maize production system that achieved mean maize yields of 13.0 t ha?1 on 66 on-farm experimental plots—nearly twice the yield of current farmers’ practices—with no increase in N fe...

  11. Wing shape and size of the western corn rootworm (Coleoptera: Chrysomelidae) is related to sex and resistance to soybean-maize crop rotation.

    Science.gov (United States)

    Mikac, K M; Douglas, J; Spencer, J L

    2013-08-01

    The western corn rootworm, Diabrotica virgifera virgifera LeConte, is a major pest of maize in the United States and more recently, Europe. Understanding the dispersal dynamics of this species will provide crucial information for its management. This study used geometric morphometric analysis of hind wing venation based on 13 landmarks in 223 specimens from nine locations in Illinois, Nebraska, Iowa, and Missouri, to assess whether wing shape and size differed between rotated and continuously grown maize where crop rotation-resistant and susceptible individuals are found, respectively. Before assessing differences between rotation-resistant and susceptible individuals, sexual dimorphism was investigated. No significant difference in wing (centroid) size was found between males and females; however, females had significantly different shaped (more elongated) wings compared with males. Wing shape and (centroid) size were significantly larger among individuals from rotated maize where crop-rotation resistance was reported; however, cross-validation of these results revealed that collection site resistance status was an only better than average predictor of shape in males and females. This study provides preliminary evidence of wing shape and size differences in D. v. virgifera from rotated versus continuous maize. Further study is needed to confirm whether wing shape and size can be used to track the movement of rotation-resistant individuals and populations as a means to better inform management strategies. PMID:24020261

  12. 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.

  13. 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> 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)

  14. 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.

  15. 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 improvementdow. 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

  16. Desempenho de genótipos de algodoeiro na presença ou não de rotação de cultura com Crotalaria spectabilis, em área infestada com Meloidogyne incognita Performance of cotton genotypes in the presence or absence of crop rotation with Crotalaria spectabilis in an area infested with Meloidogyne incognita

    Directory of Open Access Journals (Sweden)

    Rafael Galbieri

    2011-10-01

    Full Text Available Em área naturalmente infestada com Meloidogyneincognita raça 3, localizada em Primavera do Leste-MT, foi estudado o desempenho de 21 genótipos de algodoeiro com níveis diversos de tolerância ao nematoide, com a adoção ou não de rotação de cultura com Crotalaria spectabilis. De modo geral a rotação diminuiu a severidade dos sintomas exibidos pelas plantas, devidos ao ataque do parasita, e promoveu aumento na produtividade de algodão. Entretanto, seu efeito não foi suficiente para tornar eficaz o desempenho de genótipos de baixa tolerância ao nematoide, os quais, mesmo na presença da leguminosa, tiveram notas para sintomas 142% maiores e produtividades de algodão 57% menores do que as cultivares mais tolerantes. Alta correlação entre as médias de produção dos genótipos na seqüência ou não da leguminosa e ausência de interação genótipo x rotação, indicaram que, embora em patamar mais elevado de produção, a tendência de desempenho dos genótipos foi a mesma na presença e na ausência da crotalária. De tal modo que, na média, a produção dos três genótipos mais tolerantes, na ausência de rotação, foi, ainda assim, 48% superior à dos genótipos mais intolerantes, na presença da crotalária. As perdas mínimas possíveis na produção, atribuíveis ao uso de genótipos intolerantes, foram estimadas em 37% na ausência da rotação e em 29% com rotação.In an area naturally infested with Meloidogyne incognita race 3, located in Primavera do Leste, Mato Grosso State, Brazil, the performance of 21 cotton genotypes having different levels of tolerance to this parasitic nematode was studied, in the presence or absence of crop rotation with Crotalaria spectabilis. A general trend was observed for crop rotation to reduce the severity of symptoms exibited by plant sowing to nematode incidence, and lead to increased cotton yield. However, its effect was not sufficient to increase the performance of genotypes with low tolerance to the parasite, which, even under the crop rotation schem, had disease sympton rates that were 142% higher and cotton yields that were 57% lower than those obtained for more tolerant genotypes. High correlation between average yield in the presence or absence of crop rotation, and absence of interaction between genotype and crop rotation, indicated that, although at higher yield level being achieved, the tendency of genotype performance remained the same in both systems. The yield of the three more tolerant genotypes in the absence of crop rotation was 48% superior to that of the three least tolerant genotypes under crop rotation. The minimum possible losses, attributable to the use of susceptible genotypes, were estimated at 37% and 29%, respectively, without crop rotation being used or under conditions of crop rotation.

  17. Desempenho de genótipos de algodoeiro na presença ou não de rotação de cultura com Crotalaria spectabilis, em área infestada com Meloidogyne incognita / Performance of cotton genotypes in the presence or absence of crop rotation with Crotalaria spectabilis in an area infested with Meloidogyne incognita

    Scientific Electronic Library Online (English)

    Rafael, Galbieri; Milton G., Fuzatto; Edivaldo, Cia; Adinara M., Welter; Sheila, Fanan.

    2011-10-01

    Full Text Available Em área naturalmente infestada com Meloidogyneincognita raça 3, localizada em Primavera do Leste-MT, foi estudado o desempenho de 21 genótipos de algodoeiro com níveis diversos de tolerância ao nematoide, com a adoção ou não de rotação de cultura com Crotalaria spectabilis. De modo geral a rotação d [...] iminuiu a severidade dos sintomas exibidos pelas plantas, devidos ao ataque do parasita, e promoveu aumento na produtividade de algodão. Entretanto, seu efeito não foi suficiente para tornar eficaz o desempenho de genótipos de baixa tolerância ao nematoide, os quais, mesmo na presença da leguminosa, tiveram notas para sintomas 142% maiores e produtividades de algodão 57% menores do que as cultivares mais tolerantes. Alta correlação entre as médias de produção dos genótipos na seqüência ou não da leguminosa e ausência de interação genótipo x rotação, indicaram que, embora em patamar mais elevado de produção, a tendência de desempenho dos genótipos foi a mesma na presença e na ausência da crotalária. De tal modo que, na média, a produção dos três genótipos mais tolerantes, na ausência de rotação, foi, ainda assim, 48% superior à dos genótipos mais intolerantes, na presença da crotalária. As perdas mínimas possíveis na produção, atribuíveis ao uso de genótipos intolerantes, foram estimadas em 37% na ausência da rotação e em 29% com rotação. Abstract in english In an area naturally infested with Meloidogyne incognita race 3, located in Primavera do Leste, Mato Grosso State, Brazil, the performance of 21 cotton genotypes having different levels of tolerance to this parasitic nematode was studied, in the presence or absence of crop rotation with Crotalaria s [...] pectabilis. A general trend was observed for crop rotation to reduce the severity of symptoms exibited by plant sowing to nematode incidence, and lead to increased cotton yield. However, its effect was not sufficient to increase the performance of genotypes with low tolerance to the parasite, which, even under the crop rotation schem, had disease sympton rates that were 142% higher and cotton yields that were 57% lower than those obtained for more tolerant genotypes. High correlation between average yield in the presence or absence of crop rotation, and absence of interaction between genotype and crop rotation, indicated that, although at higher yield level being achieved, the tendency of genotype performance remained the same in both systems. The yield of the three more tolerant genotypes in the absence of crop rotation was 48% superior to that of the three least tolerant genotypes under crop rotation. The minimum possible losses, attributable to the use of susceptible genotypes, were estimated at 37% and 29%, respectively, without crop rotation being used or under conditions of crop rotation.

  18. Gut bacteria facilitate adaptation to crop rotation in the western corn rootworm.

    Science.gov (United States)

    Chu, Chia-Ching; Spencer, Joseph L; Curzi, Matías J; Zavala, Jorge A; Seufferheld, Manfredo J

    2013-07-16

    Insects are constantly adapting to human-driven landscape changes; however, the roles of their gut microbiota in these processes remain largely unknown. The western corn rootworm (WCR, Diabrotica virgifera virgifera LeConte) (Coleoptera: Chrysomelidae) is a major corn pest that has been controlled via annual rotation between corn (Zea mays) and nonhost soybean (Glycine max) in the United States. This practice selected for a "rotation-resistant" variant (RR-WCR) with reduced ovipositional fidelity to cornfields. When in soybean fields, RR-WCRs also exhibit an elevated tolerance of antiherbivory defenses (i.e., cysteine protease inhibitors) expressed in soybean foliage. Here we show that gut bacterial microbiota is an important factor facilitating this corn specialist's (WCR's) physiological adaptation to brief soybean herbivory. Comparisons of gut microbiota between RR- and wild-type WCR (WT-WCR) revealed concomitant shifts in bacterial community structure with host adaptation to soybean diets. Antibiotic suppression of gut bacteria significantly reduced RR-WCR tolerance of soybean herbivory to the level of WT-WCR, whereas WT-WCR were unaffected. Our findings demonstrate that gut bacteria help to facilitate rapid adaptation of insects in managed ecosystems. PMID:23798396

  19. 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

  20. Optimising harvesting and storage systems for energy crops in the Netherlands

    OpenAIRE

    Huisman, W.

    2003-01-01

    For perennial crops like short rotation coppice (in particular willow), rhizomatous grasses (like miscanthus, switch grass and reed canary grass) as well as the annual crop hemp all operations for harvesting and storage are discussed. These are mowing, size reduction, densification, conservation, storage and pre-treatment. The requirements for energy conversion and co-firing are given and the effect of harvest conditions or quality is shown. The best production chains for average conditions o...

  1. 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

  2. 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.

  3. 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.

  4. 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.

  5. Spatial distribution of reniform nematode in cotton as influenced by soil texture and crop rotations.

    Science.gov (United States)

    Holguin, Claudia; Gerard, Patrick; Mueller, John D; Khalilian, Ahmad; Agudelo, Paula

    2014-11-20

    Reniform nematode (RN) is an important pest in cotton production. Knowledge of the distribution patterns of RN is essential for selecting sampling strategies and for site-specific management. A three-year study was conducted in two fields in South Carolina with the purpose of characterizing the distribution of RN using a fine-scale sampling scheme in plots representing different soil textures (field 1), and using a large-scale arbitrary sampling scheme (field 2). Horizontal distribution data showed an aggregated pattern of RN densities at planting and after harvest in both fields each year, with patches ranging from 8 to 12 m. However, a significant neighborhood structure was only detected when suitable hosts (cotton and soybean) were planted. Correlations between RN densities and percent sand and silt were detected, showing nematode densities peaked when sand content was around 60 % and declined when sand content increased above 60-65%. When fewer samples were taken in the field with more uniform sand content, % sand was a less reliable predictor of RN densities. Vertical sampling showed the highest numbers of RN were found at 15-30 cm deep after cotton, but were deeper after a non-host crop. Understanding distribution patterns of RN is essential for selecting sampling strategies and for delineating zones for site-specific management. PMID:25412010

  6. 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.

  7. 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.

  8. SELF BALANCING SYSTEM FOR ROTATING MECHANISMS

    Scientific Electronic Library Online (English)

    Marco Antonio, Meraz; Andrés, Yánez; Carlos, Jiménez; Raúl, Pichardo.

    2005-08-01

    Full Text Available 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. Abstract in english 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 e [...] quations 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.

  9. Effect of nitrogen fertilization and cover cropping systems on sorghum grain characteristics.

    Science.gov (United States)

    Kaufman, R C; Wilson, J D; Bean, S R; Presley, D R; Blanco-Canqui, H; Mikha, M

    2013-06-19

    Cover crop treatments and nitrogen (N) fertilization rates were investigated for their impact on sorghum grain quality attributes. Sorghum was planted in field plots treated with differing cover cropping systems and fertilization rates. The size (weight and diameter) and hardness of the kernels were influenced by both the cover crop and N rates. The protein content increased as the N rate increased and also with the addition of cover crops to the system. The protein digestibility values and starch granule size distributions were not affected by N rate or the cover cropping treatments. Soil properties were tested to determine relationships with grain quality attributes. The utilization of cover crops appears to increase the protein content without causing a deleterious effect on protein digestibility. The end-product quality is not hampered by the use of beneficial cropping systems necessary for sustainable agriculture. PMID:23705643

  10. 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

  11. 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.

  12. 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.

  13. Integrated Crop/Livestock Systems Research: Practical research considerations

    Science.gov (United States)

    There are many reasons for the paucity of integrated crop/livestock research and associated publications. Integrated/crop livestock experiments that involve adequate treatments and replications, as perceived by both crop and animal scientists, require large acreages, many animals, considerable labor...

  14. 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...

  15. Systems approaches to innovation in crop protection. A systematic literature review

    OpenAIRE

    Schut, M.; J Rodenburg; Klerkx, L.W.A.; Ast, A., van; Bastiaans, L.

    2014-01-01

    The objective of this paper is to explore the extent to which systems approaches to innovation are reflected in the crop protection literature and how such approaches are used. A systematic literature review is conducted to study the relation between crop protection and systems approaches to innovation in 107 publications. The analysis of the crop protection literature demonstrates that only a small fraction is systems-oriented as compared to the bulk of publications with a technology-oriente...

  16. Influência do manejo do solo e da rotação de culturas na qualidade industrial do trigo / Influence of soil management and crop rotation on characteristics that define the industrial quality of wheat

    Scientific Electronic Library Online (English)

    ELIANA MARIA, GUARIENTI; HENRIQUE PEREIRA DOS, SANTOS; JÚLIO CÉSAR BARRENECHE, LHAMBY.

    2375-23-01

    Full Text Available A qualidade industrial do trigo é afetada por fatores genéticos e ambientais, como solo, clima, tratos culturais, e outros. O presente trabalho teve como finalidade avaliar o efeito de sistemas de manejo de solo e de rotação de culturas sobre características que definem a qualidade industrial de tri [...] go (peso do hectolitro, peso de mil grãos, extração experimental de farinha, alveografia, teste de microssedimentação com lauril sulfato de sódio e número de queda). 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 (plantio direto, preparos convencionais de solo com arado de discos e de aivecas, e cultivo mínimo), e a subparcela, pelos sistemas de rotação de culturas (monocultura, um inverno e dois invernos sem trigo). O preparo convencional de solo com arado de discos e o cultivo mínimo reduziu o número de queda; o sistema de rotação com dois invernos sem trigo elevou o peso do hectolitro; a monocultura desse cereal reduziu o peso do hectolitro, elevou a força geral de glúten e a microssedimentação com lauril sulfato de sódio; a interação sistemas de manejo de solo, rotação de culturas e ano de cultivo afetou o peso de mil grãos e, o ano de cultivo teve grande influência em todas as características de qualidade industrial de trigo estudadas. Abstract in english Wheat quality is affected by genetic and environmental factors such as soil, climate and cultural traits. The objective of this study was to evaluate the effect of soil management and crop rotation systems on characteristics that define wheat industrial quality (hectoliter weight, thousand-kernel we [...] ight, milling quality, alveograph characteristics, sodium dodecyl sulphate microsedimentation test and falling number). The experimental design used was in complete randomized blocks, with split plots and three replications. Main plot consisted of the soil management systems (no-tillage system, conventional tillage with disc and moldboard plough and minimum tillage) and the subplot consisted of the crop rotation systems (monoculture, one winter and two winters without wheat). Conventional soil preparations with discs' plough reduced the falling number; the crop rotation systems with two winters without wheat increased the hectoliter weight; the monoculture of this cereal reduced the hectoliter weight, increased the gluten strength and the values obtained in the microsedimentation test with sodium lauril sulphate; the interaction of soil management, crop rotation system and year of management affected the weight of one-thousand grains and the year of cultivation had great influence in all characteristics of the industrial quality of wheat.

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

    OpenAIRE

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

    2010-01-01

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

  18. Convective Heat and Mass Transfer in Rotating Disk Systems

    CERN Document Server

    Shevchuk, Igor V

    2009-01-01

    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 unity. 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, industr

  19. 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.

  20. Microbial community structure and abundance in the rhizosphere and bulk soil of a tomato cropping system that includes cover crops

    Science.gov (United States)

    In this report we use Terminal Restriction Fragment Length Polymorphisms (TRFLP) in a tomato production system to “finger printing” the soil microbial community structure with Phylum specific primer sets. Factors influencing the soil microbes are a cover crop of Hairy Vetch (Vicia villosa) or Rye (...

  1. Efeitos do preparo do solo, plantio direto e de rotações de culturas sobre o rendimento e a economicidade do feijoeiro irrigado / Agronomic effect of soil tillage, no-tillage and crop rotation on yield of irrigated common bean

    Scientific Electronic Library Online (English)

    Pedro Marques da, Silveira; Osmira Fátima da, Silva; Luis Fernando, Stone; José Geraldo da, Silva.

    2001-02-01

    Full Text Available O objetivo deste trabalho foi identificar os efeitos de sistemas de preparo do solo e de rotações de culturas sobre o rendimento de grãos e economicidade da cultura do feijoeiro (Phaseolus vulgaris L.) irrigado pelo sistema pivô central. O trabalho foi conduzido durante seis anos consecutivos, na Em [...] brapa-Centro Nacional de Pesquisa de Arroz e Feijão, localizado no Município de Santo Antônio de Goiás, GO, em Latossolo Vermelho-Escuro, de textura argilosa. O experimento consistiu de um fatorial 4 x 6, em delineamento inteiramente casualizado, com parcelas subdivididas. Os sistemas de preparo do solo foram: P1 arado de aiveca (novembro-dezembro) alternado com grade aradora (maio-junho); P2 arado de aiveca contínuo; P3 grade aradora contínua; P4 plantio direto; e as rotações de culturas: R1 arroz-feijão; R2 milho-feijão; R3 soja-trigo, R4 soja-trigo-soja-feijão-arroz-feijão; R5 arroz consorciado com calopogônio-feijão; e R6 milho-feijão-milho-feijão-arroz -feijão. As rotações R1, R2, R3 e R5 foram anuais, e as R4 e R6, trienais. Neste trabalho analisaram-se somente as rotações que continham feijão. O arroz, o milho e a soja foram semeados em novembro-dezembro (verão), e o feijão e o trigo, em maio-junho (inverno). Houve efeito do preparo do solo e das rotações de cultura sobre o rendimento de grãos do feijoeiro. A cultura produziu mais quando se utilizou no preparo do solo a combinação de arado de aiveca, nos cultivos de verão, e grade aradora nos de inverno. Os rendimentos do feijoeiro foram maiores quando a cultura foi implantada bienalmente na mesma área, nas rotações com arroz/calopogônio e arroz, e menores, nas rotações com milho. O feijoeiro irrigado, com relação ao preparo do solo e rotações de culturas, foi economicamente viável, propiciando taxas de retorno que variaram de 67% a 97%. Abstract in english The objective of this study was to evaluate the agronomic effect of soil tillage and crop rotation on grain yield of common bean (Phaseolus vulgaris L.) irrigated by central pivot. The study was conducted at the Embrapa-Centro Nacional de Pesquisa de Arroz e Feijão, in a Dark-Red Latosol with clay t [...] exture, during six consecutive years. Basic experiment was a 4 x 6 factorial, having a completely randomized block design with subdivided plots. Soil tillage systems were: P1 moldboard plough (November-December), alternated with harrow disc (May-June); P2 moldboard plough; P3 harrow disc, and P4 no-tillage. The crop rotations used were: R1 rice-common bean; R2 corn-common bean; R3 soybean-wheat; R4 soybean-wheat-soybean-common bean-rice-common bean; R5 rice associated with Calopogonium mucunoides-common bean; and R6 corn-common bean-corn-common bean-rice-common bean. The crop rotations R1, R2, R3, and R5 were annual and R4 and R6 were triennial; in this study, only rotations with common bean were evaluated. Rice, corn and soybean were sown in November/December (summer) and common bean and wheat in May/June (winter). Grain yield of common bean was influenced by soil tillage and crop rotation. Yield was higher under soil prepared with moldboard plough in combination with summer sowing and prepared with harrow disc in winter sowing. Common bean grain yield was higher when biannual sowing was done in the same area in rotation with rice/C. mucunoides and rice, and lower in rotation with corn. Irrigated common bean crop was economically viable as a function of soil tillage and crop rotation and economic return varied from 67% to 97%.

  2. Efeitos do preparo do solo, plantio direto e de rotações de culturas sobre o rendimento e a economicidade do feijoeiro irrigado Agronomic effect of soil tillage, no-tillage and crop rotation on yield of irrigated common bean

    Directory of Open Access Journals (Sweden)

    Pedro Marques da Silveira

    2001-02-01

    Full Text Available O objetivo deste trabalho foi identificar os efeitos de sistemas de preparo do solo e de rotações de culturas sobre o rendimento de grãos e economicidade da cultura do feijoeiro (Phaseolus vulgaris L. irrigado pelo sistema pivô central. O trabalho foi conduzido durante seis anos consecutivos, na Embrapa-Centro Nacional de Pesquisa de Arroz e Feijão, localizado no Município de Santo Antônio de Goiás, GO, em Latossolo Vermelho-Escuro, de textura argilosa. O experimento consistiu de um fatorial 4 x 6, em delineamento inteiramente casualizado, com parcelas subdivididas. Os sistemas de preparo do solo foram: P1 arado de aiveca (novembro-dezembro alternado com grade aradora (maio-junho; P2 arado de aiveca contínuo; P3 grade aradora contínua; P4 plantio direto; e as rotações de culturas: R1 arroz-feijão; R2 milho-feijão; R3 soja-trigo, R4 soja-trigo-soja-feijão-arroz-feijão; R5 arroz consorciado com calopogônio-feijão; e R6 milho-feijão-milho-feijão-arroz -feijão. As rotações R1, R2, R3 e R5 foram anuais, e as R4 e R6, trienais. Neste trabalho analisaram-se somente as rotações que continham feijão. O arroz, o milho e a soja foram semeados em novembro-dezembro (verão, e o feijão e o trigo, em maio-junho (inverno. Houve efeito do preparo do solo e das rotações de cultura sobre o rendimento de grãos do feijoeiro. A cultura produziu mais quando se utilizou no preparo do solo a combinação de arado de aiveca, nos cultivos de verão, e grade aradora nos de inverno. Os rendimentos do feijoeiro foram maiores quando a cultura foi implantada bienalmente na mesma área, nas rotações com arroz/calopogônio e arroz, e menores, nas rotações com milho. O feijoeiro irrigado, com relação ao preparo do solo e rotações de culturas, foi economicamente viável, propiciando taxas de retorno que variaram de 67% a 97%.The objective of this study was to evaluate the agronomic effect of soil tillage and crop rotation on grain yield of common bean (Phaseolus vulgaris L. irrigated by central pivot. The study was conducted at the Embrapa-Centro Nacional de Pesquisa de Arroz e Feijão, in a Dark-Red Latosol with clay texture, during six consecutive years. Basic experiment was a 4 x 6 factorial, having a completely randomized block design with subdivided plots. Soil tillage systems were: P1 moldboard plough (November-December, alternated with harrow disc (May-June; P2 moldboard plough; P3 harrow disc, and P4 no-tillage. The crop rotations used were: R1 rice-common bean; R2 corn-common bean; R3 soybean-wheat; R4 soybean-wheat-soybean-common bean-rice-common bean; R5 rice associated with Calopogonium mucunoides-common bean; and R6 corn-common bean-corn-common bean-rice-common bean. The crop rotations R1, R2, R3, and R5 were annual and R4 and R6 were triennial; in this study, only rotations with common bean were evaluated. Rice, corn and soybean were sown in November/December (summer and common bean and wheat in May/June (winter. Grain yield of common bean was influenced by soil tillage and crop rotation. Yield was higher under soil prepared with moldboard plough in combination with summer sowing and prepared with harrow disc in winter sowing. Common bean grain yield was higher when biannual sowing was done in the same area in rotation with rice/C. mucunoides and rice, and lower in rotation with corn. Irrigated common bean crop was economically viable as a function of soil tillage and crop rotation and economic return varied from 67% to 97%.

  3. An overview of crop growing condition monitoring in China agriculture remote sensing monitoring system

    Science.gov (United States)

    Huang, Qing; Zhou, Qing-bo; Zhang, Li

    2009-07-01

    China is a large agricultural country. To understand the agricultural production condition timely and accurately is related to government decision-making, agricultural production management and the general public concern. China Agriculture Remote Sensing Monitoring System (CHARMS) can monitor crop acreage changes, crop growing condition, agriculture disaster (drought, floods, frost damage, pest etc.) and predict crop yield etc. quickly and timely. The basic principles, methods and regular operation of crop growing condition monitoring in CHARMS are introduced in detail in the paper. CHARMS can monitor crop growing condition of wheat, corn, cotton, soybean and paddy rice with MODIS data. An improved NDVI difference model was used in crop growing condition monitoring in CHARMS. Firstly, MODIS data of every day were received and processed, and the max NDVI values of every fifteen days of main crop were generated, then, in order to assessment a certain crop growing condition in certain period (every fifteen days, mostly), the system compare the remote sensing index data (NDVI) of a certain period with the data of the period in the history (last five year, mostly), the difference between NDVI can indicate the spatial difference of crop growing condition at a certain period. Moreover, Meteorological data of temperature, precipitation and sunshine etc. as well as the field investigation data of 200 network counties were used to modify the models parameters. Last, crop growing condition was assessment at four different scales of counties, provinces, main producing areas and nation and spatial distribution maps of crop growing condition were also created.

  4. 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)

  5. Fibre Optic System for Monitoring Rotational Seismic Phenomena

    OpenAIRE

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

    2014-01-01

    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 operatio...

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

    Directory of Open Access Journals (Sweden)

    Andréia Patrícia Andrade

    2012-05-01

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

  7. 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.

  8. Network-assisted crop systems genetics: network inference and integrative analysis.

    Science.gov (United States)

    Lee, Tak; Kim, Hyojin; Lee, Insuk

    2015-04-01

    Although next-generation sequencing (NGS) technology has enabled the decoding of many crop species genomes, most of the underlying genetic components for economically important crop traits remain to be determined. Network approaches have proven useful for the study of the reference plant, Arabidopsis thaliana, and the success of network-based crop genetics will also require the availability of a genome-scale functional networks for crop species. In this review, we discuss how to construct functional networks and elucidate the holistic view of a crop system. The crop gene network then can be used for gene prioritization and the analysis of resequencing-based genome-wide association study (GWAS) data, the amount of which will rapidly grow in the field of crop science in the coming years. PMID:25698380

  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 for the country. The primary objective of this research is to map rice cropping systems and predict future dynamics of rice cropping systems using MODIS time-series data from 2002 to 2012. A phenology-based classification approach was applied for the classification and assessment of rice cropping systems. Then, the Cellular Automata-Markov (CA-Markov) model was used to simulate future changes in rice-cropping activities. To obtain precise prediction, a calibration of CA-Markov were implemented by using a series of rice crop maps. The comparisons between the classification maps and the ground reference data indicated satisfactory results with overall accuracies above 81%, and Kappa coefficients above 0.75, respectively. The simulated maps of rice cropping systems for 2010-2012 were extrapolated by CA-Markov model based on the trend of rice cropping systems during 2002-2009. The comparison between the predicted scenarios and the classification maps for 2010-2012 presents a reasonably close agreement. In summary, the CA-Markov model with a long-term calibration confirmed the validity of the approach for dynamic modeling of changes in rice cropping systems in the study region. The results obtained from this study demonstrate that the approach produced satisfactory results in terms of accuracy, quantitative forecast, and spatial pattern changes. Thus, projections of future changes would provide useful information for the agricultural policymakers in respect to formulating effective management strategies of rice cropping practices in VMD.

  10. Nitrous oxide and methane emissions from optimized and alternative cereal cropping systems on the North China Plain: A two-year field study

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Bing [College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China); Ju, Xiaotang, E-mail: juxt@cau.edu.cn [College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China); Su, Fang; Meng, Qingfeng [College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China); Oenema, Oene [Wageningen University and Research, Alterra, Wageningen (Netherlands); Christie, Peter [College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China); Agri-Environment Branch, Agri-Food and Biosciences Institute, Belfast BT9 5PX (United Kingdom); Chen, Xinping; Zhang, Fusuo [College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China)

    2014-02-01

    The impacts of different crop rotation systems with their corresponding management practices on grain yield, greenhouse gas emissions, and fertilizer nitrogen (N) and irrigation water use efficiencies are not well documented. This holds especially for the North China Plain which provides the staple food for hundreds of millions of people and where groundwater resources are polluted with nitrate and depleted through irrigation. Here, we report on fertilizer N and irrigation water use, grain yields, and nitrous oxide (N{sub 2}O) and methane (CH{sub 4}) emissions of conventional and optimized winter wheat–summer maize double-cropping systems, and of three alternative cropping systems, namely a winter wheat–summer maize (or soybean)–spring maize system, with three harvests in two years; and a single spring maize system with one crop per year. The results of this two-year study show that the optimized double-cropping system led to a significant increase in grain yields and a significant decrease in fertilizer N use and net greenhouse gas intensity, but the net greenhouse gas N{sub 2}O emissions plus CH{sub 4} uptake and the use of irrigation water did not decrease relative to the conventional system. Compared to the conventional system the net greenhouse gas emissions, net greenhouse gas intensity and use of fertilizer N and irrigation water decreased in the three alternative cropping systems, but at the cost of grain yields except in the winter wheat–summer maize–spring maize system. Net uptake of CH{sub 4} by the soil was little affected by cropping system. Average N{sub 2}O emission factors were only 0.17% for winter wheat and 0.53% for maize. In conclusion, the winter wheat–summer maize–spring maize system has considerable potential to decrease water and N use and decrease N{sub 2}O emissions while maintaining high grain yields and sustainable use of groundwater. - Highlights: • Yields, resource use efficiency and N{sub 2}O + CH{sub 4} emission differ among cropping systems. • An alternative cropping system is recommended for the North China Plain region. • A rotation cycle of it is in sequence winter wheat, summer maize and spring maize. • This alternative is better than an optimized winter wheat–summer maize system. • It is sustainable due to saving water and N, maintaining yields and reducing GHG.

  11. Nitrous oxide and methane emissions from optimized and alternative cereal cropping systems on the North China Plain: A two-year field study

    International Nuclear Information System (INIS)

    The impacts of different crop rotation systems with their corresponding management practices on grain yield, greenhouse gas emissions, and fertilizer nitrogen (N) and irrigation water use efficiencies are not well documented. This holds especially for the North China Plain which provides the staple food for hundreds of millions of people and where groundwater resources are polluted with nitrate and depleted through irrigation. Here, we report on fertilizer N and irrigation water use, grain yields, and nitrous oxide (N2O) and methane (CH4) emissions of conventional and optimized winter wheat–summer maize double-cropping systems, and of three alternative cropping systems, namely a winter wheat–summer maize (or soybean)–spring maize system, with three harvests in two years; and a single spring maize system with one crop per year. The results of this two-year study show that the optimized double-cropping system led to a significant increase in grain yields and a significant decrease in fertilizer N use and net greenhouse gas intensity, but the net greenhouse gas N2O emissions plus CH4 uptake and the use of irrigation water did not decrease relative to the conventional system. Compared to the conventional system the net greenhouse gas emissions, net greenhouse gas intensity and use of fertilizer N and irrigation water decreased in the three alternative cropping systems, but at the cost of grain yields except in the winter wheat–summer maize–spring maize system. Net uptake of CH4 by the soil was little affected by cropping system. Average N2O emission factors were only 0.17% for winter wheat and 0.53% for maize. In conclusion, the winter wheat–summer maize–spring maize system has considerable potential to decrease water and N use and decrease N2O emissions while maintaining high grain yields and sustainable use of groundwater. - Highlights: • Yields, resource use efficiency and N2O + CH4 emission differ among cropping systems. • An alternative cropping system is recommended for the North China Plain region. • A rotation cycle of it is in sequence winter wheat, summer maize and spring maize. • This alternative is better than an optimized winter wheat–summer maize system. • It is sustainable due to saving water and N, maintaining yields and reducing GHG

  12. Incorporation of Green Manure Plants into Bean Cropping Systems Contribute to Root-Knot Nematode Suppression

    OpenAIRE

    Kimenju, J. W.; 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...

  13. 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.

  14. 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)

  15. Asynchronous rotation in close binary systems with circular orbits

    Science.gov (United States)

    Habets, G. M. H. J.; Zwaan, C.

    1989-02-01

    The origin of asynchronism observed in some binary systems in which the components rotate much more rapidly or much more slowly than the orbital rate was investigated using Pylyser's (1988) evolutionary models of stars of 1.0, 1.5, and 2.0 solar masses. Under the assumption of rigid-body rotation, the evolution of the angular rotation velocity from the main sequence up to the red-giant branch is derived; the orbital circularity of these systems is explained by strong tidal interaction, either during the early premain-sequence phase, or, for systems containing a white dwarf, during the red-giant phase of its progenitor. It is argued that, at the zero-age main sequence (ZAMS), the binary components rotate much faster than the orbital rate. During the evolution off the ZAMS, the angular rotation rate of the components decreases, mainly because of the increase of the moment of inertia, and, possibly, because of magnetic braking.

  16. The Effect of Organic and Conventional Cropping Systems on CO2 Emission from Agricultural Soils: Preliminary Results

    Directory of Open Access Journals (Sweden)

    Stefano Grego

    2007-06-01

    Full Text Available The effects of different agricultural systems on soil organic carbon content and CO2 emission are investigated in this work. In a long-term experiment a conventional system, characterized by traditional agricultural practices (as deep tillage and chemical inputs was compared with an organic one, including green manure and organic fertilizers. Both systems have a three-year crop rotation including pea – durum wheat – tomato; the organic system is implemented with the introduction of common vetch (Vicia sativa L. and sorghum (Sorghum vulgare bicolor as cover crops. In the year 2006 (5 years after the experimentation beginning was determined the soil C content and was measured the CO2 emissions from soil. The first results showed a trend of CO2 production higher in organic soils in comparison with conventional one. Among the two compared cropping systems the higher differences of CO2 emission were observed in tomato soil respect to the durum wheat and pea soils, probably due to the vetch green manuring before the tomato transplanting. These results are in agreement with the total organic carbon content and water soluble carbon (WSC, which showed the highest values in organic soil. The first observations suggest a higher biological activity and CO2 emission in organic soil than conventional one, likely due to a higher total carbon soil content.

  17. The Effect of Organic and Conventional Cropping Systems on CO2 Emission from Agricultural Soils: Preliminary Results

    Directory of Open Access Journals (Sweden)

    Stefano Grego

    2011-02-01

    Full Text Available The effects of different agricultural systems on soil organic carbon content and CO2 emission are investigated in this work. In a long-term experiment a conventional system, characterized by traditional agricultural practices (as deep tillage and chemical inputs was compared with an organic one, including green manure and organic fertilizers. Both systems have a three-year crop rotation including pea – durum wheat – tomato; the organic system is implemented with the introduction of common vetch (Vicia sativa L. and sorghum (Sorghum vulgare bicolor as cover crops. In the year 2006 (5 years after the experimentation beginning was determined the soil C content and was measured the CO2 emissions from soil. The first results showed a trend of CO2 production higher in organic soils in comparison with conventional one. Among the two compared cropping systems the higher differences of CO2 emission were observed in tomato soil respect to the durum wheat and pea soils, probably due to the vetch green manuring before the tomato transplanting. These results are in agreement with the total organic carbon content and water soluble carbon (WSC, which showed the highest values in organic soil. The first observations suggest a higher biological activity and CO2 emission in organic soil than conventional one, likely due to a higher total carbon soil content.

  18. Phase considerations in a rotating system

    International Nuclear Information System (INIS)

    A neutron interferometer in constant absolute rotation will exhibit a certain phase-shift between its two beams, a phenomenon shared with the classic Sagnac or Michelson-Gale-Pearson experiments or with the modern laser-gyrocompass composed of lasers in a ring. To first order in the rotational frequency, it is possible to understand by employing only rudimentary theory, the essence of this phenomenon to any degree of relativistiness of the participating particle. This paper is mainly paedagogical, noting the similarity due to permanent rotation between photon-, electron and neutron-interferometers. Future experimentation, aside from corroborating well believed tenets, may hope with improving precision to bring new approaches to measurement of fundamental effects

  19. 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.

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

    Directory of Open Access Journals (Sweden)

    Edmilson José Ambrosano

    2010-12-01

    Full Text Available A cana-de-açúcar (Saccharum spp. vem sendo cultivada no Brasil para produção de açúcar e agroenergia. Em seu sistema de produção, após um ciclo de 4 a 8 anos, é possível a rotação com plantas de cobertura, antes do seu replantio, para melhoria do solo e geração de renda. Estudou-se a caracterização e produtividade de biomassa de leguminosas (como adubos-verdes e girassol (Helianthus annuus L., a ocorrência natural de micorrizas, o teor de açúcar e a produtividade em colmos da cana-de-açúcar IAC 87-3396 e a viabilidade econômica desse sistema com cultivo após as opções de rotação, com quantificação da produtividade durante três cortes consecutivos. O amendoim (Arachis hypogaea L. cv. IAC-Caiapó, girassol cv. IAC-Uruguai e mucuna-preta (Mucuna aterrimum Piper and Tracy foram as culturas que apresentaram maior percentagem de colonização por fungos micorrízicos. O girassol foi a planta de cobertura que mais extraiu nutrientes do solo, seguido por amendoim (Arachis hipogaea L. cv. IAC-Tatu e feijão-mungo (Vigna radiata L. Wilczek. A colonização por fungos micorrízicos mostrou correlação positiva com a altura de plantas de cana no primeiro corte (p = 0,01 e R = 0,52, mas não se correlacionou com a produtividade de colmos ou açúcar. No primeiro corte, o girassol foi a cultura de rotação que ocasionou o maior aumento de produtividade, da ordem de 46% em colmos e de 50% na quantidade de açúcar, em comparação com a testemunha. Com exceção dos amendoins, todas as culturas em rotação aumentaram a renda líquida do sistema na média de três cortes de cana-de-açúcar.Sugarcane (Saccharum spp. is an important crop for sugar production and agro-energy purposes in Brazil. In the sugarcane production system after a 4- to 8-year cycle crop rotation may be used before replanting sugarcane to improve soil conditions and give an extra income. This study had the objective of characterizing the biomass and the 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.

  1. A quality assessment of the MARS crop yield forecasting system for the European Union

    Science.gov (United States)

    van der Velde, Marijn; Bareuth, Bettina

    2015-04-01

    Timely information on crop production forecasts can become of increasing importance as commodity markets are more and more interconnected. Impacts across large crop production areas due to (e.g.) extreme weather and pest outbreaks can create ripple effects that may affect food prices and availability elsewhere. The MARS Unit (Monitoring Agricultural ResourceS), DG Joint Research Centre, European Commission, has been providing forecasts of European crop production levels since 1993. The operational crop production forecasting is carried out with the MARS Crop Yield Forecasting System (M-CYFS). The M-CYFS is used to monitor crop growth development, evaluate short-term effects of anomalous meteorological events, and provide monthly forecasts of crop yield at national and European Union level. The crop production forecasts are published in the so-called MARS bulletins. Forecasting crop yield over large areas in the operational context requires quality benchmarks. Here we present an analysis of the accuracy and skill of past crop yield forecasts of the main crops (e.g. soft wheat, grain maize), throughout the growing season, and specifically for the final forecast before harvest. Two simple benchmarks to assess the skill of the forecasts were defined as comparing the forecasts to 1) a forecast equal to the average yield and 2) a forecast using a linear trend established through the crop yield time-series. These reveal a variability in performance as a function of crop and Member State. In terms of production, the yield forecasts of 67% of the EU-28 soft wheat production and 80% of the EU-28 maize production have been forecast superior to both benchmarks during the 1993-2013 period. In a changing and increasingly variable climate crop yield forecasts can become increasingly valuable - provided they are used wisely. We end our presentation by discussing research activities that could contribute to this goal.

  2. 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...

  3. Behavior of Atrazine In Limited Irrigation Cropping Systems in Colorado: Prior Use Is Important

    Science.gov (United States)

    The Irrigation Water Optimization Project was begun in 2005 at Colorado State University to develop cropping systems to optimize use of limited irrigation water supply while sustaining production. Corn is a major component of many of these cropping systems and atrazine is used to provide residual w...

  4. Life cycle assessment of various cropping systems utilized for producing biofuels: Bioethanol and biodiesel

    International Nuclear Information System (INIS)

    A life cycle assessment of different cropping systems emphasizing corn and soybean production was performed, assuming that biomass from the cropping systems is utilized for producing biofuels (i.e., ethanol and biodiesel). The functional unit is defined as 1 ha of arable land producing biomass for biofuels to compare the environmental performance of the different cropping systems. The external functions are allocated by introducing alternative product systems (the system expansion allocation approach). Nonrenewable energy consumption, global warming impact, acidification and eutrophication are considered as potential environmental impacts and estimated by characterization factors given by the United States Environmental Protection Agency (EPA-TRACI). The benefits of corn stover removal are (1) lower nitrogen related environmental burdens from the soil, (2) higher ethanol production rate per unit arable land, and (3) energy recovery from lignin-rich fermentation residues, while the disadvantages of corn stover removal are a lower accumulation rate of soil organic carbon and higher fuel consumption in harvesting corn stover. Planting winter cover crops can compensate for some disadvantages (i.e., soil organic carbon levels and soil erosion) of removing corn stover. Cover crops also permit more corn stover to be harvested. Thus, utilization of corn stover and winter cover crops can improve the eco-efficiency of the cropping systems. When biomass from the cropping systemsms. When biomass from the cropping systems is utilized for biofuel production, all the cropping systems studied here offer environmental benefits in terms of nonrenewable energy consumption and global warming impact. Therefore utilizing biomass for biofuels would save nonrenewable energy, and reduce greenhouse gases. However, unless additional measures such as planting cover crops were taken, utilization of biomass for biofuels would also tend to increase acidification and eutrophication, primarily because large nitrogen (and phosphorus)-related environmental burdens are released from the soil during cultivation

  5. Evaluation of a distributed parameter ecohydrological model (TOPOG_IRM) on a small cropping rotation catchment

    Science.gov (United States)

    Dawes, Warrick R.; Zhang, Lu; Hatton, Tom J.; Reece, Peter H.; Beale, G. T. H.; Packer, I.

    1997-04-01

    A biophysically based distributed parameter ecohydrological catchment model, TOPOG_IRM, is described which predicts the dynamic interactions between soil-vegetation-atmosphere systems over a catchment. The physiological control on transpiration is formulated using canopy resistance defined as a function of the net assimilation rate, the relative humidity and CO 2 concentration at the leaf surface. Rainfall infiltration, runoff and redistribution are simulated with the Richards equation and evapotranspiration is calculated using the Penman-Monteith equation. Two innovative features of the model are (1) coupling of the vegetation-atmosphere system by changing the value of the vapour pressure deficit of air in the canopy, and (2) the plant carbon balance, which allows the simulation of plant growth using a saturation rate kinetics formulation. The model was validated using evapotranspiration, soil moisture and leaf area index measurements from Wagga Wagga, N.S.W., Australia, for a period of 1992-1993. The calculated evapotranspiration was in good agreement with the observations. The soil moisture content at various depths was well simulated for two typical sites. The model also reasonably reproduced leaf area index of wheat and canola for two growing seasons. The success of the model simulations was due to the reasonably realistic treatment of the soil and canopy processes. The sensitivity analysis indicated that (1) the maximum assimilation rate of carbon affects canopy transpiration significantly, and (2) the total drainage is sensitive to the lower boundary conditions and the saturated hydraulic conductivity. TOPOG_IRM is a valuable tool in studying catchment responses under different land management practices. However, the application of the model is limited by the large amount of data required regarding soil and vegetation properties, and their spatial distribution.

  6. Can subsurface drip irrigation (SDI) be a competitive irrigation system in the Great Plains region for commodity crops

    Science.gov (United States)

    Subsurface drip irrigation (SDI) as with all microirrigation systems is typically only used on crops with greater value. In the U.S. Great Plains region, the typical irrigated crops are the cereal and oil seed crops and cotton. These crops have less economic revenue than typical microirrigated cro...

  7. A WEB BASED TOMATO CROP EXPERT INFORMATION SYSTEM BASED ON ARTIFICIAL INTELLIGENCE AND MACHINE LEARNING ALGORITHMS

    Directory of Open Access Journals (Sweden)

    Prasad Babu M.S

    2010-03-01

    Full Text Available Tomato is now the most widely grown vegetable crop in World. It is grown throughout the world in farm gardens, small home-gardens, and by market gardeners for fresh consumption as well as for processingpurposes. This Tomato crop expert advisory system is aimed at a collaborative venture with eminent Agriculture Scientist and Experts in the area of Tomato Plantation with an excellent team of computer Engineers, programmers and designers. This Expert System contains two main parts one is Tomato Information System and the other is Tomato Crop Expert System where in Information system, the user can get all the static information about different species, Diseases,Symptoms, chemical controls, Preventions, Pests, Virus of Tomato fruits and plants. In Advisory System, the user is having aninteraction with the expert system online; the user has to answer the questions asked by the Expert System. Depends on the response by the user the expert system decides the disease and displays its control measure of disease. This Tomato Crop Information Expert System deals with different varieties of Tomato Crop, Identification of various diseases generally occurs to tomato crop based on the symptoms.This Rule based Expert System validates the symptoms of the tomato crop using the techniques of ID3 Algorithm and some optimization algorithms. This is a Web based Expert System with java as the front end and SQL as the backend.

  8. Multi-Attribute Modelling of Economic and Ecological Impacts of Cropping Systems

    OpenAIRE

    Bohanec, M.; Dzeroski, S.; Znidarsic, M.; Messe?an, A.; Scatasta, S.; Wesseler, J. H. H.

    2004-01-01

    Modelling of economic and ecological impacts of genetically modified crops is a demanding task. We present some preliminary attempts made for the purpose of the ECOGEN project "Soil ecological and economic evaluation of genetically modified crops". One of the goals of the project is to develop a computer-based decision support system for the assessment of economic and ecological impacts of using genetically modified crops, with special emphasis on soil biology and ecology. The decision suppor...

  9. Use of isotope techniques in evaluation of fertilizer management practices for cropping systems

    International Nuclear Information System (INIS)

    The methods by which isotopic techniques have been used in sole cropping studies are reviewed, and the application of those techniques to complex cropping systems is discussed. Strip intercropping, sequential cropping, and relay, row, and mixed intercropping are shown to present many complexities which isotopes could play an important role in clarifying. The depth, spread and activity of rooting systems can be studied with P-32 or P-33, and double labelling may be very informative in defining the interpenitration or changes in rooting pattern resulting from intercropping. Nitrification inhibitors with N-15 labelled fertilizer may be useful in restricting fertilizer N to the non-fixing component of row or mixed intercropping systems. Similarly, P-32, N-15 and S-35 labelled fertilizers may be useful for fertilizer placement studies. Where legumes are included in the cropping systems N-15 abundance techniques can be used to estimate the contribution of N biologically fixed by the legume to the entire cropping system. (author)

  10. Crop residues as raw materials for biorefinery systems - A LCA case study

    International Nuclear Information System (INIS)

    Our strong dependence on fossil fuels results from the intensive use and consumption of petroleum derivatives which, combined with diminishing oil resources, causes environmental and political concerns. The utilization of agricultural residues as raw materials in a biorefinery is a promising alternative to fossil resources for production of energy carriers and chemicals, thus mitigating climate change and enhancing energy security. This paper focuses on a biorefinery concept which produces bioethanol, bioenergy and biochemicals from two types of agricultural residues, corn stover and wheat straw. These biorefinery systems are investigated using a Life Cycle Assessment (LCA) approach, which takes into account all the input and output flows occurring along the production chain. This approach can be applied to almost all the other patterns that convert lignocellulosic residues into bioenergy and biochemicals. The analysis elaborates on land use change aspects, i.e. the effects of crop residue removal (like decrease in grain yields, change in soil N2O emissions and decrease of soil organic carbon). The biorefinery systems are compared with the respective fossil reference systems producing the same amount of products/services from fossils instead of biomass. Since climate change mitigation and energy security are the two most important driving forces for biorefinery development, the assessment focuses on greenhouse gas (GHG) emissions and cumulative primary enerGHG) emissions and cumulative primary energy demand, but other environmental categories are evaluated as well. Results show that the use of crop residues in a biorefinery saves GHG emissions and reduces fossil energy demand. For instance, GHG emissions are reduced by about 50% and more than 80% of non-renewable energy is saved. Land use change effects have a strong influence in the final GHG balance (about 50%), and their uncertainty is discussed in a sensitivity analysis. Concerning the investigation of the other impact categories, biorefinery systems have higher eutrophication potential than fossil reference systems. Based on these results, a residues-based biorefinery concept is able to solve two problems at the same time, namely find a use for the abundant lignocellulosic residues and ensure a mitigation effect for most of the environmental concerns related to the utilization of non-renewable energy resources. Therefore, when agricultural residues are used as feedstocks, best management practices and harvest rates need to be carefully established. In fact, rotation, tillage, fertilization management, soil properties and climate can play an important role in the determination of the amount of crop residue that can be removed minimizing soil carbon losses.

  11. Impact of sole cropping and multiple cropping on soil humified carbon fractions

    International Nuclear Information System (INIS)

    The present study was planned to improve our understanding how crop rotation can enhance humified C fractions. A long term experiment was conducted on Vanmeter farm of the Ohio State University South Centers at Piketon Ohio, USA from 2002 to 2007. Crop rotation treatments included were continuous corn (CC), corn-soybean (CS) and corn-soybean-wheat-cowpea (CSW) rotations. Randomized complete block design with 6 replications was used under natural field conditions. The findings of this long-term study revealed that multiple cropping had significantly improved humified carbon fractions compared to mono-cropping system. Although total humified carbon (THOC), sugar free humified carbon (HOC) concentration were non-significant however, humin (NH) contents, humic (HA), fulvic acids (FA), humic and fulvic acid associated glucose (HA-NH and FA-NH) were significantly affected by various crop rotations within five years. The soil under CC had 22-52% significantly greater NH concentration than CSW and CS rotations respectively. Similarly all crop rotations had shown 5-16 increase in HA and 5-17% decreased in FA over time. Likewise soil under CC had 16 and 54% greater HA-NH concentration as compared to CSW and CS rotations. The FA-NH concentration increased significantly by 27- 51% in soil under all treatments over time. The soil under CSW had greater HA/FA (1.6) fallowed by CC (1.4) and CS (1.1). Soils under CSW had significantly greater HA/HOC (12-18%) as compare to CC and CS respectively. Conversely, the value of FA/HOC decreased (1-23%) in soil under all crop rotation treatments within five years. Degree of humification (DH) had shown a significant increase (7-12%) in soil under all treatments as compared to 2002. Irrespective of crop rotation THOC, HOC, NH, humin, HA, HR and FA/HOC concentration decreased significantly with increase in soil depth. While fulvic acid concentration HA/HOC in all crop rotation increased with increase in soil depth. The effect of crop rotation on humified C fractions could be because of variations in type, amount and quality of C returned by different plants into the soil. So replacing mono-cropping with multiple cropping can enhance humified C fractions and can improve soil functional properties. (author)

  12. On the dynamics of slowly rotating stellar systems

    International Nuclear Information System (INIS)

    Kinematical observations are now available for stellar systems which might rotate slowly. The study of periodic orbits in model stellar systems shows that a mean motion in epicyclic or circular orbits contributes to balance the centrifugal force, in addition to the velocity dispersions. Two dynamical models, the generalized Toomre and Plummer models, are adapted to the case of slow rotation. They are applied to two globular clusters, M3 and 47 Tucanae, and 12 clusters of galaxies. 47 Tucanae is found to rotate, but none of the clusters of galaxies has any significant mean motion, except SC 316-44. 34 refs., 1 fig., 3 tabs. (author)

  13. Implications of Cereal-Based Crop Rotations, Nitrogen Fertilization, and Stubble Grazing on Soil Organic Matter in a Mediterranean-Type Environment

    OpenAIRE

    Ryan, John; MASRI, S.; ?BR?KÇ?, Hayriye; Singh, M.; PALA, Mustafa

    2008-01-01

    Soil organic matter (SOM) is essential to all soil processes that have an impact on crop production and the environment. Soils of the semi-arid Mediterranean region are low in SOM due to environmental conditions (temperature, moisture) and centuries of cultivation. Hence, as SOM has a major influence on soil aggregation, nutrient supply, and soil moisture, as well as the relationships between them, there is a need to assess the impact of cropping systems on this critical soil parameter. Durin...

  14. Integrating livestock manure with a corn-soybean bioenergy cropping system improves short-term carbon sequestration rates and net global warming potential

    International Nuclear Information System (INIS)

    Carbon cycling and the global warming potential (GWP) of bioenergy cropping systems with complete biomass removal are of agronomic and environmental concern. Corn growers who plan to remove corn stover as a feedstock for the emerging cellulosic ethanol industry will benefit from carbon amendments such as manure and compost, to replace carbon removed with the corn stover. The objective of this research was to determine the effect of beef cattle feedlot manure and composted dairy manure on short-term carbon sequestration rates and net global warming potential (GWP) in a corn-soybean rotation with complete corn-stover removal. Field experiments consisting of a corn-soybean rotation with whole-plant corn harvest, were conducted near East Lansing, MI over a three-year period beginning in 2002. Compost and manure amendments raised soil carbon (C) at a level sufficient to overcome the C debt associated with manure production, manure collection and storage, land application, and post-application field emissions. The net GWP in carbon dioxide equivalents for the manure and compost amended cropping systems was -934 and -784 g m-2 y-1, respectively, compared to 52 g m-2 y-1 for the non-manure amended synthetic fertilizer check. This work further substantiates the environmental benefits associated with renewable fuels and demonstrates that with proper management, the integration of livestock manures in biofuel cropping systems can enhanures in biofuel cropping systems can enhance greenhouse gas (GHG) remediation. (author)

  15. 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

  16. 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

  17. Pattern diversities in cropping systems in tribal regions: a case study of Jhabua tribal district in Madhya Pradesh, India

    OpenAIRE

    Singh, Vivek Kumar; Singh, Rd

    2011-01-01

    Agricultural development has been analysed by studying the cropping pattern and cropping diversification and crop specialization in any agro-ecosystem in regional and temporal framework. Tribal regions are experiencing agricultural intensification through diversification of cropping systems and crop specialization as a result of ecological economic changes as well as impact of public policy of technology transfer and resource use intensification. The market forces also are influencing the cro...

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

    International Nuclear Information System (INIS)

    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.

  19. Water Erosion in Relation with Soil Management System and Crop Sequence during 20 Years on an Inceptisol in South Brazil

    Science.gov (United States)

    Bertol, I.; Schick, J.; Barbosa, F. T.; Paz-Ferreiro, J.; Flores, M. T.; Paz González, A.

    2012-04-01

    Soil erosion still remains persistent at the world scale, even if big efforts have been done to control and reduce it, mainly using soil crop residues to protect soil surface. Although in South Brazil the main management system for most crops is no tillage and direct drilling, water erosion prevails as the most important soil erosion type, which is due both, to the high erosivity and the evenly distribution of rainfall over the year. Moreover, some crops are still grown under soil tillage systems consisting of ploughing, harrowing and less frequently chiselling. Starting 1992, a field experiment under natural rainfall has been conducted on an Inceptisol located in Lages, Santa Catarina State, Brazil, which objective was to assess rainfall water erosion. Two soil cover conditions and four soil management systems were studied: I) a crop rotation, which included oats (Avena strigosa), soybean (Glycine max), common vetch (Vicia sativa), maize (Zea mays), fodder radish (Raphanus sativus) and common bean (Phaseolus vulgaris) under the following soil management types: 1) ploughing plus two levelling operations (CT), chiselling plus levelling (RT) and direct drilling with no tillage (NT), and II) bare soil (BS) without crop cover tilled by ploughing plus two levelling. In more than 90% of the study cases, soil losses were collected for single rain events with erosive power, whose erosivity was calculated. Total rain recorded during the 20 year experimental period was approximately 66,400 mm, which is equivalent to roughly 105,700, MJ mm ha-1 h-1 (EI30), whereas soil losses in the BS treatment were higher than 1,700 t.ha-1. On average, soil losses under RT treatment showed a 92% reduction in relation with BS, whereas under CT the reduction in relation to BS was about 66%. Soil management by direct drilling (NT) was the most efficient system to minimize water erosion, as soil losses decreased about 98% when compared with BS. Moreover, soil management systems with a crop rotation, i.e., RT, CT, and NT, showed a lower efficiency in the reduction of water losses with regard to the efficiency of soil losses decrease. So many rainfall events during our experimental period showed similar water losses for all the management and crop systems, which was mainly true for rainfalls causing high volumes of runoff and with a small time interval between successive events. During the autumn-winter seasons water losses were lower than in the spring-summer seasons, whereas greater soil losses in the spring-summer season were solely recorded in the CT and BS treatments. Heavy water losses by runoff recorder under conservation tillage, specifically in the NT management system suggest the need for adoption of additional structural conservation practices, such as for example terracing, in order to supplement the positive effect of soil cover by crop residues in controlling water erosion. Soil losses showed a positive correlation with rainfall erosivity and the significance of this relationship decreased as the efficiency of soil management system for the control of soil erosion increased.

  20. Soil phosphatase and urease activities impacted by cropping systems and water management

    Science.gov (United States)

    Soil enzymes can play an important role in nutrient availability to plants. Consequently, soil enzyme measurements can provide useful information on soil fertility for crop production. We examined the impact of cropping system and water management on phosphatase, urease, and microbial biomass C in s...

  1. COVER CROP, AMENDMENT, AND TILLAGE EFFECTS ON COLLEMBOLANS AND NEMATODES IN AN ORGANIC VEGETABLE SYSTEM

    Science.gov (United States)

    Soil organisms are sensitive indicators of changes in soil properties. This study reports the effects of different organic management practices on soil collembolans and nematodes. Cropping systems in the experiment vary the cover crop species, tillage frequency, and planting time. The two organic...

  2. MODELING GREENHOUSE GAS EMISSIONS FROM BIOENERGY CROPPING SYSTEMS IN PENNSYLVANIA USING DAYCENT

    Science.gov (United States)

    Reducing the net global warming potential (GWP) of energy use is a major factor driving interest in biofuels. Bioenergy cropping systems vary in contribution to the GWP due to the crop yield and resulting quantity of fossil fuels displaced, quantity and quality of C added to the soil, feedstock conv...

  3. Grazing winter rye cover crop in a cotton no-till system: yield and economics

    Science.gov (United States)

    Winter cover crop adoption in conservation management systems continues to be limited in the US but could be encouraged if establishment costs could be offset. A 4-yr field experiment was conducted near Watkinsville, Georgia in which a rye (Secale cereale L.) cover crop was either grazed by catt...

  4. An Assessment of some Fertilizer Recommendations under Different Cropping Systems in a Humid Tropical Environment

    OpenAIRE

    Fondufe, EY.; Eneji, AE.; Agboola, AA.; S. Yamamoto; T. Honna

    2001-01-01

    Studies were carried out to determine the effects of four fertilizer recommendation systems (bianket recommendation, soil test recommendation, recommendation based on nutrient supplementation index and unfertilized control) on five cropping systems (sole cassava, maize, melon, cassava + maize and cassava + maize + melon). The experiment was a split-plot in randomised complete block design, with fertilizer recommendation systems in main plots and cropping systems in subplots. Observations were...

  5. Economics of wheat based cropping systems in rainfed areas of pakistan

    International Nuclear Information System (INIS)

    The Pothwar tract of rainfed area has enormous potential to meet incremental food grain needs of the country. However, a significant yield gap in wheat has been reported between yields of substantive and the progressive growers mainly due to poor management of soil, water and fertility issues. A field study was conducted at National Agricultural Research Centre (NARC), Islamabad and the traditional wheat-fallow-wheat (W-F-W) cropping system was evaluated with the improved wheat-maize fodder-wheat (W-MF-W) and wheat-mungbean-wheat (W-MB-W) cropping systems. Two tillage practices, i.e. shallow tillage with cultivator and deep tillage with moldboard; and four fertilizer treatments viz., control (C), recommended dose of fertilizer for each crop (F), farmyard manure (FYM) at the rate -15 tha . The recommended doses of fertilizer for individual crop with FYM (F+FYM) were also included in the study to know their impact on the crops yield in the cropping systems. Economic analysis of the data revealed that the traditional wheat-fallow-wheat cropping system could be economically replaced with wheat-maize fodder-wheat cropping system even under drought condition and there will be no economical loss of wheat yield when planted after maize fodder. Application of recommended dose of fertilizer -1 along with FYM at the rate 5 tha will enhance the yield of wheat and maize fodder. The improved cropping system of wheat-maize fodder-wheat will help the farmers to sustain productivity ohelp the farmers to sustain productivity of these crops, stable economic benefits and improvement in soil nutrients and organic matter over time. (author)

  6. Global crop production forecasting - A simulation analysis of the data system problems and their solutions

    Science.gov (United States)

    Golden, H.; Neiers, J. W.

    1978-01-01

    Alternative data systems for a global crop production forecasting system were studied with the aid of a unique simulation facility called the Data System Dynamic Simulator (DSDS). Information system requirements were determined and compared with existing and planned data systems, and deficiencies were identified and analyzed. A first step was to determine the data load for an operational global crop production forecasting system as a function of data frequency, crop types, biophases, cloud coverage, and number of satellites. The DSDS was used to correlate the interrelated influence of orbital parameters, crop calendars, and cloud conditions to generate global data loading profiles. Some of the more important conclusions and the main features of the simulation system are presented.

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

    OpenAIRE

    A.S. Nascente; C.A.C. Crusciol; L.F Stone; T Cobucci

    2013-01-01

    The appropriate chemical management of cover crops in no-tillage aims to obtain greater benefits with its employment in agricultural systems. The objective of this study was to assess upland rice yield as affected by the previous summer crop, species and desiccation timing of cover crops by glyphosate. Sown cover crops were sown (November 2007), followed by rice in half of the experimental area and soybean in the other half (November 2008). After the harvesting of these crops, the same cover ...

  8. [Application of ICP-MS to detection of heavy metals in soil from different cropping systems].

    Science.gov (United States)

    Rui, Yu-Kui; Kong, Xiang-Bin; Qin, Jing

    2007-06-01

    With the rapid development of the society, more and more attention has been paid to the influence of human activity on environment and food pollution. Soils of different cropping systems, sampled from Daxing district of Beijing, were analyzed in terms of the contents of heavy metals (Ti, Cr, Mn, Ni, Cu, Zn, As, Cd and Pb) by the method of ICP-MS to determine the influence of cropping system on environment. The results showed that the contents of nine heavy metals in soils from the cropping systems (fruits and maize/wheat) were several times higher than those from vegetable system. Contents of Cr, Mn, Ni, Cu, Zn, As and Cd were the highest in soils from fruit system, while Ti and Pb the highest in soils from maize/wheat system. The causes of the above differences could be the different harvest organs for different crops. PMID:17763792

  9. 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

  10. Open Quantum System Stochastic Dynamics and the Rotating Wave Approximation

    OpenAIRE

    Band, Y. B.

    2014-01-01

    We study the stochastic dynamics of a two-level quantum system interacting with a stochastic magnetic field, and a single frequency electromagnetic field, with and without making the rotating wave approximation (RWA). The transformation to the rotating frame does not commute with the stochastic Hamiltonian if the stochastic field has nonvanishing components in the transverse direction. Hence, making the RWA modifies the stochastic terms in the Hamiltonian. Modification of th...

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

    Scientific Electronic Library Online (English)

    Guillermo Adrián, Divito; Hernán, Sainz Rozas; Hernán Eduardo, Echeverría.

    2010-07-01

    Full Text Available En suelos del sudeste Bonaerense el fósforo (P) del fertilizante forma productos de mediana a alta solubilidad, lo cual le confiere un alto valor residual. A partir de esto, surge la posibilidad de definir estrategias de fertilización basadas en la frecuencia con que se efectúa su aplicación. Para r [...] otaciones de cuatro cultivos en tres años se desconoce el efecto de alternativas de fertilización fosfatada. Los objetivos fueron: 1) evaluar el rendimiento de cultivos fertilizados con P anualmente y cada tres años, a la rotación de cultivos, y 2) determinar la eficiencia de uso y de recuperación del P (EUP y ERP, respectivamente) aplicado para dichas estrategias de fertilización. El experimento se realizó sobre un complejo de Paleudol Petrocálcico y Argiudol Típico en la EEA I.N.T.A. Balcarce, con un alto nivel inicial de P-Bray (28,7 mg kg-1) y bajo siembra directa. A lo largo de dos ciclos de rotación, integrados por maíz, soja y trigo/soja de segunda, se evaluaron tres tratamientos: aplicación de P con frecuencia anual, por única vez a la rotación y un testigo sin P, en bloques completos aleatorizados con cuatro repeticiones. No se observaron diferencias en el rendimiento de los cultivos fertilizados en forma anual y a la rotación, durante los dos ciclos. El testigo difirió de los tratamientos fertilizados solo durante el segundo ciclo de rotación. La EUP de la rotación (EUProt) no difirió entre estrategias de aplicación (19,4 y 32,4 kg kg-1 durante el primer ciclo y 32,9 y 37,4 kg kg-1 durante el segundo, para tratamientos fertilizados anualmente y a la rotación, respectivamente). Tampoco existieron diferencias entre estrategias de fertilización en la EUP de cada cultivo. En cambio, durante el primer ciclo, la ERP resultó mayor para el tratamiento fertilizado a la rotación respecto de la aplicación anual (0,13 y 0,03 kg kg-1), mientras que en el segundo ciclo no se detectaron diferencias entre ambos (0,16 y 0,17 kg kg-1 para la aplicación anual y a la rotación, respectivamente). Se encontró una débil asociación entre la variación anual en el nivel de P-Bray y el balance de P correspondiente al cultivo implantado dicho año. Para el tratamiento testigo, se elaboró un modelo para predecir la disminución en el P disponible considerando el nivel inicial de P-Bray y la exportación de P de los cultivos como variables. Abstract in english In the soils of southeast Buenos Aires, fertilizer phosphorus (P) forms medium to high solubility products, making it possible to define different fertilization strategies based on application frequency. The effect of P application rates capable of fulfilling all crop requirements in intensive rotat [...] ions in the region is unknown. The objectives of this work were to: (1) assess yields in crops fertilized with P annually and once during the crop rotation and (2) determine P use efficiency and P recovery for each fertilization strategy. The experiment was conducted at the E.E.A. I.N.T.A. Balcarce on a Typic Argiudoll and Petrocalcic Paleudoll complex, under no-tillage and with high P-Bray (Bray & Kurts, 1945) content (28.7 mg kg-1). During the two rotation cycles for maize, soybean, and double wheat/soybean crop, three treatments were assessed: application of P annually, application once during the rotation cycle, and a control without P application. The experimental design was in randomized blocks with four repetitions. No crop yield differences were found between annual and rotation fertilization strategies across the two cycles evaluated. The control crop yield did not differ from the fertilized crop during the first rotation cycle but did during the second. The crop rotation P use efficiency (EUProt) did not differ between nutrient applications strategies (19.4 and 32.4 kg kg-1 during the first cycle and 32.9 and 37.4 kg kg-1 during the second for annually and rotation fertilized treatments respectively). There were no differences between strategies in the crop P use efficiency of each crop (EUPcult). In contrast, during t

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

    Directory of Open Access Journals (Sweden)

    Guillermo Adrián Divito

    2010-07-01

    Full Text Available En suelos del sudeste Bonaerense el fósforo (P del fertilizante forma productos de mediana a alta solubilidad, lo cual le confiere un alto valor residual. A partir de esto, surge la posibilidad de definir estrategias de fertilización basadas en la frecuencia con que se efectúa su aplicación. Para rotaciones de cuatro cultivos en tres años se desconoce el efecto de alternativas de fertilización fosfatada. Los objetivos fueron: 1 evaluar el rendimiento de cultivos fertilizados con P anualmente y cada tres años, a la rotación de cultivos, y 2 determinar la eficiencia de uso y de recuperación del P (EUP y ERP, respectivamente aplicado para dichas estrategias de fertilización. El experimento se realizó sobre un complejo de Paleudol Petrocálcico y Argiudol Típico en la EEA I.N.T.A. Balcarce, con un alto nivel inicial de P-Bray (28,7 mg kg-1 y bajo siembra directa. A lo largo de dos ciclos de rotación, integrados por maíz, soja y trigo/soja de segunda, se evaluaron tres tratamientos: aplicación de P con frecuencia anual, por única vez a la rotación y un testigo sin P, en bloques completos aleatorizados con cuatro repeticiones. No se observaron diferencias en el rendimiento de los cultivos fertilizados en forma anual y a la rotación, durante los dos ciclos. El testigo difirió de los tratamientos fertilizados solo durante el segundo ciclo de rotación. La EUP de la rotación (EUProt no difirió entre estrategias de aplicación (19,4 y 32,4 kg kg-1 durante el primer ciclo y 32,9 y 37,4 kg kg-1 durante el segundo, para tratamientos fertilizados anualmente y a la rotación, respectivamente. Tampoco existieron diferencias entre estrategias de fertilización en la EUP de cada cultivo. En cambio, durante el primer ciclo, la ERP resultó mayor para el tratamiento fertilizado a la rotación respecto de la aplicación anual (0,13 y 0,03 kg kg-1, mientras que en el segundo ciclo no se detectaron diferencias entre ambos (0,16 y 0,17 kg kg-1 para la aplicación anual y a la rotación, respectivamente. Se encontró una débil asociación entre la variación anual en el nivel de P-Bray y el balance de P correspondiente al cultivo implantado dicho año. Para el tratamiento testigo, se elaboró un modelo para predecir la disminución en el P disponible considerando el nivel inicial de P-Bray y la exportación de P de los cultivos como variables.In the soils of southeast Buenos Aires, fertilizer phosphorus (P forms medium to high solubility products, making it possible to define different fertilization strategies based on application frequency. The effect of P application rates capable of fulfilling all crop requirements in intensive rotations in the region is unknown. The objectives of this work were to: (1 assess yields in crops fertilized with P annually and once during the crop rotation and (2 determine P use efficiency and P recovery for each fertilization strategy. The experiment was conducted at the E.E.A. I.N.T.A. Balcarce on a Typic Argiudoll and Petrocalcic Paleudoll complex, under no-tillage and with high P-Bray (Bray & Kurts, 1945 content (28.7 mg kg-1. During the two rotation cycles for maize, soybean, and double wheat/soybean crop, three treatments were assessed: application of P annually, application once during the rotation cycle, and a control without P application. The experimental design was in randomized blocks with four repetitions. No crop yield differences were found between annual and rotation fertilization strategies across the two cycles evaluated. The control crop yield did not differ from the fertilized crop during the first rotation cycle but did during the second. The crop rotation P use efficiency (EUProt did not differ between nutrient applications strategies (19.4 and 32.4 kg kg-1 during the first cycle and 32.9 and 37.4 kg kg-1 during the second for annually and rotation fertilized treatments respectively. There were no differences between strategies in the crop P use efficiency of each crop (EUPcult. In contrast, during the first cycle, the applied P recovery efficiency (E

  13. Rhizo-lysimetry: facilities for the simultaneous study of root behaviour and resource use by agricultural crop and pasture systems

    Science.gov (United States)

    2013-01-01

    Background Rhizo-lysimeters offer unique advantages for the study of plants and their interactions with soils. In this paper, an existing facility at Charles Sturt University in Wagga Wagga Australia is described in detail and its potential to conduct both ecophysiological and ecohydrological research in the study of root interactions of agricultural crops and pastures is quantitatively assessed. This is of significance to future crop research efforts in southern Australia, in light of recent significant long-term drought events, as well as potential impacts of climate change as predicted for the region. The rhizo-lysimeter root research facility has recently been expanded to accommodate larger research projects over multiple years and cropping rotations. Results Lucerne, a widely-grown perennial pasture in southern Australia, developed an expansive root system to a depth of 0.9 m over a twelve month period. Its deeper roots particularly at 2.05 m continued to expand for the duration of the experiment. In succeeding experiments, canola, a commonly grown annual crop, developed a more extensive (approximately 300%) root system than wheat, but exhibited a slower rate of root elongation at rates of 7.47 x 10–3 m day–1 for canola and 1.04 x10–2 m day–1 for wheat. A time domain reflectometry (TDR) network was designed to accurately assess changes in soil water content, and could assess water content change to within 5% of the amount of water applied. Conclusions The rhizo-lysimetry system provided robust estimates of root growth and soil water change under conditions representative of a field setting. This is currently one of a very limited number of global research facilities able to perform experimentation under field conditions and is the largest root research experimental laboratory in the southern hemisphere. PMID:23363534

  14. Rhizo-lysimetry: facilities for the simultaneous study of root behaviour and resource use by agricultural crop and pasture systems

    Directory of Open Access Journals (Sweden)

    Eberbach Philip L

    2013-01-01

    Full Text Available Abstract Background Rhizo-lysimeters offer unique advantages for the study of plants and their interactions with soils. In this paper, an existing facility at Charles Sturt University in Wagga Wagga Australia is described in detail and its potential to conduct both ecophysiological and ecohydrological research in the study of root interactions of agricultural crops and pastures is quantitatively assessed. This is of significance to future crop research efforts in southern Australia, in light of recent significant long-term drought events, as well as potential impacts of climate change as predicted for the region. The rhizo-lysimeter root research facility has recently been expanded to accommodate larger research projects over multiple years and cropping rotations. Results Lucerne, a widely-grown perennial pasture in southern Australia, developed an expansive root system to a depth of 0.9 m over a twelve month period. Its deeper roots particularly at 2.05 m continued to expand for the duration of the experiment. In succeeding experiments, canola, a commonly grown annual crop, developed a more extensive (approximately 300% root system than wheat, but exhibited a slower rate of root elongation at rates of 7.47 x 10–3 m day–1 for canola and 1.04 x10–2 m day–1 for wheat. A time domain reflectometry (TDR network was designed to accurately assess changes in soil water content, and could assess water content change to within 5% of the amount of water applied. Conclusions The rhizo-lysimetry system provided robust estimates of root growth and soil water change under conditions representative of a field setting. This is currently one of a very limited number of global research facilities able to perform experimentation under field conditions and is the largest root research experimental laboratory in the southern hemisphere.

  15. Scope for improved eco-efficiency varies among diverse cropping systems

    OpenAIRE

    Carberry, Peter S.; Liang, Wei-li; Twomlow, Stephen; Holzworth, Dean P.; Dimes, John P.; Mcclelland, Tim; Huth, Neil I.; Chen, Fu; Hochman, Zvi; Keating, Brian A.

    2013-01-01

    Global food security requires eco-efficient agriculture to produce the required food and fiber products concomitant with ecologically efficient use of resources. This eco-efficiency concept is used to diagnose the state of agricultural production in China (irrigated wheat–maize double-cropping systems), Zimbabwe (rainfed maize systems), and Australia (rainfed wheat systems). More than 3,000 surveyed crop yields in these three countries were compared against simulated grain yields at farmer-...

  16. Analysis and modelling of rotational systems with the Modyfit application

    Directory of Open Access Journals (Sweden)

    S. ?ó?kiewski

    2008-09-01

    Full Text Available Purpose: of this article is to present an application to analysis and modelling of rotational systems. Independent modules of application enables controlling and regulation of characteristics of systems in transportation. The base problem of analyzing systems in transportation is expressing the interaction between the main motion and local vibrations of subsystems.Design/methodology/approach: Mathematical models derived in previous articles were used to implement the mathematical models in numerical calculations. The objectives of creating the Modyfit application were connected with analyzing and modelling rotating systems with taking into account relations between major and local motions. Considerations were done by the Galerkin’s method.Findings: There are many effects of analyzing systems with rotation consideration. Main of them are connected with analyzing systems in function of increasing the value of angular velocity. In such way of analyzing we can observe creating additional poles in the dynamical characteristics and we can also observe that instead of modes there are created zeros.Research limitations/implications: Analyzed systems are simple linear homogeneous beams and rods. Working motion is limited to plane motion. Future research would consider complex systems, damping and nonlinearity.Practical implications: of the application are numerical analysis of beams and rods in rotational transportation and designing such systems. Thank to the Modyfit we can derived the stability zones of analyzed beams and rods and we can observe eigenfrequencies and zeros in function of angular velocity.Originality/value: The Modyfit is a forerunner implementation of derived models in a numerical environment of dynamical flexibility. Analyzing models are rotating flexible systems with consideration the rotational transportation effect.

  17. The influence of tagasaste (chamaecytisus proliferus link) trees on the water balance of an alley cropping system on deep sand in south-western Australia)

    International Nuclear Information System (INIS)

    Components of the water balance of an alley cropping system were measured to assess the extent to which tree rows 30 m apart with access to a fresh, perched watertable at 5 m depth were able to capture deep drainage from an inter-cropped cereal-legume rotation. Neutron probe data showed that the 4-year-old trees, cut back to 0.6-m high at the beginning of the experiment, depleted soil water to 2, 4, and 8 m laterally from the tree rows in their first, second, and third years of coppice regrowth, respectively. Combining data from soil water depletion in summer and comparisons of deuterium/hydrogen ratios of groundwater, xylem sap of trees, and herbaceous plants, it was shown that tagasaste trees drew on soil water for 80% of their transpiration in the first winter and 40% in the second, while switching to near total dependence on groundwater each summer and early autumn. Tree water use on a whole plot basis was 170 mm in 1997 (68% from groundwater) v. 167 mm in 1998 (73% from groundwater). Recharge to the perched watertable was estimated to be 193 mm under sole crop in 1998 (52% of rainfall), reducing to 32 mm when uptake of groundwater by trees was included. The degree of complementarity between tagasaste trees and crops in alley cropping used for water management is quantified for 1998 by calculating the ratio of the distance over which trees reduced drainage to zero to the distance over which they reduced crop yield to zero. It is concluded that segregated monocultu It is concluded that segregated monocultures of trees and crops would be a more appropriate strategy than a closely integrated system such as alley cropping in this case. Copyright (2001) CSIRO Australia

  18. Energy crops in Ireland: An economic comparison of willow and Miscanthus production with conventional farming systems

    OpenAIRE

    Styles,David

    2008-01-01

    Recent full decoupling of EU agricultural subsidy payments from production in Ireland is forecast to result in substantial destocking of grassland over the coming decade. In conjunction with increased energy prices, this presents new opportunities for energy crops. This paper uses extensive literature review and country-specific information on current prices to construct life-cycle cost assessments for production of Miscanthus and short-rotation coppice willow (SRCW) in Ireland. Gross margins...

  19. 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.

  20. Management of nitrogen and evaluation of water-use efficiency in traditional and improved cropping systems of the southern Telangana region of Andhra Pradesh, India

    International Nuclear Information System (INIS)

    A collaborative research project among the International Atomic Energy Agency, Acharya N.G. Ranga Agricultural University and the International Crops Research Institute for the Semi-Arid Tropics, was initiated in 1999 with the objective of developing a set of options for improving the nitrogen (N) nutrition of dry-land cropping systems by use of N from biological N2 fixation, fertilizer and organic matter at the Regional Agricultural Research Station, Palem, Mahabubnagar District, Andhra Pradesh. The main experiment consisted of traditional (sorghum-castor) and improved (sorghum/pigeon pea-castor) cropping systems on a two-year rotation cycle with four N-management options. Nitrogen-15-labelled fertilizer and farmyard manure (FYM) were included as sources of N. In spite of low rainfall (390 mm in 1999; and 450 mm in 2000) both sorghum and castor responded to applied N. Intercropped pigeon pea had beneficial effects on the succeeding castor crop. A grain yield advantage of 88 kg ha-1 was obtained with castor following sorghum/pigeon pea compared to that following sole sorghum. In on-farm participatory trials, the yields of sorghum, castor and pigeon pea were substantially higher with improved practice compared to farmers' practice. There was no significant difference between urea alone and urea plus FYM as a source of N to sorghum and castor-based cropping systems. (author)

  1. Impacts of Organic Zero Tillage Systems on Crops, Weeds, and Soil Quality

    Directory of Open Access Journals (Sweden)

    Patrick M. Carr

    2013-07-01

    Full Text Available Organic farming has been identified as promoting soil quality even though tillage is used for weed suppression. Adopting zero tillage and other conservation tillage practices can enhance soil quality in cropping systems where synthetic agri-chemicals are relied on for crop nutrition and weed control. Attempts have been made to eliminate tillage completely when growing several field crops organically. Vegetative mulch produced by killed cover crops in organic zero tillage systems can suppress annual weeds, but large amounts are needed for adequate early season weed control. Established perennial weeds are not controlled by cover crop mulch. Integrated weed management strategies that include other cultural as well as biological and mechanical controls have potential and need to be incorporated into organic zero tillage research efforts. Market crop performance in organic zero tillage systems has been mixed because of weed, nutrient cycling, and other problems that still must be solved. Soil quality benefits have been demonstrated in comparisons between organic conservation tillage and inversion tillage systems, but studies that include zero tillage treatments are lacking. Research is needed which identifies agronomic strategies for optimum market crop performance, acceptable levels of weed suppression, and soil quality benefits following adoption of organic zero tillage.

  2. Influence of Previous Crop on Durum Wheat Yield and Yield Stability in a Long-term Experiment

    Directory of Open Access Journals (Sweden)

    Anna Maria Stellacci

    2011-02-01

    Full Text Available Long-term experiments are leading indicators of sustainability and serve as an early warning system to detect problems that may compromise future productivity. So the stability of yield is an important parameter to be considered when judging the value of a cropping system relative to others. In a long-term rotation experiment set up in 1972 the influence of different crop sequences on the yields and on yield stability of durum wheat (Triticum durum Desf. was studied. The complete field experiment is a split-split plot in a randomized complete block design with two replications; the whole experiment considers three crop sequences: 1 three-year crop rotation: sugar-beet, wheat + catch crop, wheat; 2 one-year crop rotation: wheat + catch crop; 3 wheat continuous crop; the split treatments are two different crop residue managements; the split-split plot treatments are 18 different fertilization formulas. Each phase of every crop rotation occurred every year. In this paper only one crop residue management and only one fertilization treatment have been analized. Wheat crops in different rotations are coded as follows: F1: wheat after sugar-beet in three-year crop rotation; F2: wheat after wheat in three-year crop rotation; Fc+i: wheat in wheat + catch crop rotation; Fc: continuous wheat. The following two variables were analysed: grain yield and hectolitre weight. Repeated measures analyses of variance and stability analyses have been perfomed for the two variables. The stability analysis was conducted using: three variance methods, namely the coefficient of variability of Francis and Kannenberg, the ecovalence index of Wricke and the stability variance index of Shukla; the regression method of Eberhart and Russell; a method, proposed by Piepho, that computes the probability of one system outperforming another system. It has turned out that each of the stability methods used has enriched of information the simple variance analysis. The Piepho’s probability method, moreover, abridges in effective way the analysis of variance results, supplying precise indications about the influence of crop sequence on quali-quantitative productive variables; in particular, wheats in three-year crop rotation (F1 and F2 have higher probability to obtain higher qualitative and quantitative productions than one in one-year crop rotations (Fc+i and Fc, so as wheat in one-year crop rotation with catch crop vs. wheat monoculture.

  3. Influence of Previous Crop on Durum Wheat Yield and Yield Stability in a Long-term Experiment

    Directory of Open Access Journals (Sweden)

    Anna Maria Stellacci

    2007-09-01

    Full Text Available Long-term experiments are leading indicators of sustainability and serve as an early warning system to detect problems that may compromise future productivity. So the stability of yield is an important parameter to be considered when judging the value of a cropping system relative to others. In a long-term rotation experiment set up in 1972 the influence of different crop sequences on the yields and on yield stability of durum wheat (Triticum durum Desf. was studied. The complete field experiment is a split-split plot in a randomized complete block design with two replications; the whole experiment considers three crop sequences: 1 three-year crop rotation: sugar-beet, wheat + catch crop, wheat; 2 one-year crop rotation: wheat + catch crop; 3 wheat continuous crop; the split treatments are two different crop residue managements; the split-split plot treatments are 18 different fertilization formulas. Each phase of every crop rotation occurred every year. In this paper only one crop residue management and only one fertilization treatment have been analized. Wheat crops in different rotations are coded as follows: F1: wheat after sugar-beet in three-year crop rotation; F2: wheat after wheat in three-year crop rotation; Fc+i: wheat in wheat + catch crop rotation; Fc: continuous wheat. The following two variables were analysed: grain yield and hectolitre weight. Repeated measures analyses of variance and stability analyses have been perfomed for the two variables. The stability analysis was conducted using: three variance methods, namely the coefficient of variability of Francis and Kannenberg, the ecovalence index of Wricke and the stability variance index of Shukla; the regression method of Eberhart and Russell; a method, proposed by Piepho, that computes the probability of one system outperforming another system. It has turned out that each of the stability methods used has enriched of information the simple variance analysis. The Piepho’s probability method, moreover, abridges in effective way the analysis of variance results, supplying precise indications about the influence of crop sequence on quali-quantitative productive variables; in particular, wheats in three-year crop rotation (F1 and F2 have higher probability to obtain higher qualitative and quantitative productions than one in one-year crop rotations (Fc+i and Fc, so as wheat in one-year crop rotation with catch crop vs. wheat monoculture.

  4. Emergy Assessment of a Wheat-Maize Rotation System with Different Water Assignments in the North China Plain

    Science.gov (United States)

    Hu, Shi; Mo, Xingguo; Lin, Zhonghui; Qiu, Jianxiu

    2010-10-01

    Sustainable water use is seriously compromised in the North China Plain (NCP) due to the huge water requirements of agriculture, the largest use of water resources. An integrated approach which combines the ecosystem model with emergy analysis is presented to determine the optimum quantity of irrigation for sustainable development in irrigated cropping systems. Since the traditional emergy method pays little attention to the dynamic interaction among components of the ecological system and dynamic emergy accounting is in its infancy, it is hard to evaluate the cropping system in hypothetical situations or in response to specific changes. In order to solve this problem, an ecosystem model (Vegetation Interface Processes (VIP) model) is introduced for emergy analysis to describe the production processes. Some raw data, collected by investigating or observing in conventional emergy analysis, may be calculated by the VIP model in the new approach. To demonstrate the advantage of this new approach, we use it to assess the wheat-maize rotation cropping system at different irrigation levels and derive the optimum quantity of irrigation according to the index of ecosystem sustainable development in NCP. The results show, the optimum quantity of irrigation in this region should be 240-330 mm per year in the wheat system and no irrigation in the maize system, because with this quantity of irrigation the rotation crop system reveals: best efficiency in energy transformation (transformity = 6.05E + 4 sej/J); highest sustainability (renewability = 25%); lowest environmental impact (environmental loading ratio = 3.5) and the greatest sustainability index (Emergy Sustainability Index = 0.47) compared with the system in other irrigation amounts. This study demonstrates that application of the new approach is broader than the conventional emergy analysis and the new approach is helpful in optimizing resources allocation, resource-savings and maintaining agricultural sustainability.

  5. Inertial waves in the channel turbulence with system rotation

    Science.gov (United States)

    Yang, Yan-Tao; Wu, Jie-Zhi

    2010-11-01

    We study inertial waves (IWs) in the turbulent channel flow with system rotation about an axis in either streamwise or spanwise direction (STR or SPR). For the mean channel shear flow, we construct IW solutions by the helical wave functions (eigenfunctions of the curl operator), and show their existence when the basic flow satisfies certain conditions. These theoretical predictions were tested by DNS of the rotating channel flows. We have recently confirmed that the STR channel holds IWs when the rotating rate is high enough, and for different rotating rates the IWs have similar wavenumber and negative polarity (JFM, to appear). As for the SPR cases, the IWs may exist at even higher rotating rates than that needed for STR cases. They locate at the layer where the mean streamwise velocity is largest. It is likely that when a system rotation is applied to a unidirectional shear flow, the IWs may appear at the region where the mean streamwise velocity takes the local maximum. The profiles of the mean velocity are modified by IWs.

  6. Consideration in selecting crops for the human-rated life support system: a Linear Programming model

    Science.gov (United States)

    Wheeler, E. F.; Kossowski, J.; Goto, E.; Langhans, R. W.; White, G.; Albright, L. D.; Wilcox, D.; Henninger, D. L. (Principal Investigator)

    1996-01-01

    A Linear Programming model has been constructed which aids in selecting appropriate crops for CELSS (Controlled Environment Life Support System) food production. A team of Controlled Environment Agriculture (CEA) faculty, staff, graduate students and invited experts representing more than a dozen disciplines, provided a wide range of expertise in developing the model and the crop production program. The model incorporates nutritional content and controlled-environment based production yields of carefully chosen crops into a framework where a crop mix can be constructed to suit the astronauts' needs. The crew's nutritional requirements can be adequately satisfied with only a few crops (assuming vitamin mineral supplements are provided) but this will not be satisfactory from a culinary standpoint. This model is flexible enough that taste and variety driven food choices can be built into the model.

  7. Nitrogen Release from Green Manure of Water Hyacinth in Rice Cropping Systems

    Directory of Open Access Journals (Sweden)

    Didik Wisnu Widjajanto

    2002-01-01

    Full Text Available Nitrogen derived from water hyacinth and recovered in rice crops was measured to evaluate the effect of different amounts of added water hyacinth residues into rice cultivation on the performance of rice crop, N derived (Ndev from residues and N recovery (Nrec in rice crop. Dry matter production and N yield of rice crop decreased significantly as the amounts of added water hyacinth increased. The Ndev from water hyacinth was significantly increased as amounts of added water hyacinth increased. In contrast, the Nrec in rice crop was significantly decreased as amounts of added water hyacinth increased. In conclusion different quantities of added water hyacinth residues influenced the performance of rice, and the N dynamics of soil-rice systems.

  8. Energy crops for biogas plants. Brandenburg; Energiepflanzen fuer Biogasanlagen. Brandenburg

    Energy Technology Data Exchange (ETDEWEB)

    Adam, L.; Barthelmes, G.; Biertuempfel, A. (and others)

    2012-06-15

    In the brochure under consideration, the Agency for Renewable Resources (Guelzen-Pruezen, Federal Republic of Germany) reported on recommendations on alternative cropping systems for energy crop rotations in order to achieve high yields in combination with high diversity, risk spreading and sustainability. In particular, the natural site conditions in the Federal State of Brandenburg (Federal Republic of Germany) are determined.

  9. Crop monitoring & yield forecasting system based on Synthetic Aperture Radar (SAR) and process-based crop growth model: Development and validation in South and South East Asian Countries

    Science.gov (United States)

    Setiyono, T. D.

    2014-12-01

    Accurate and timely information on rice crop growth and yield helps governments and other stakeholders adapting their economic policies and enables relief organizations to better anticipate and coordinate relief efforts in the wake of a natural catastrophe. Such delivery of rice growth and yield information is made possible by regular earth observation using space-born Synthetic Aperture Radar (SAR) technology combined with crop modeling approach to estimate yield. Radar-based remote sensing is capable of observing rice vegetation growth irrespective of cloud coverage, an important feature given that in incidences of flooding the sky is often cloud-covered. The system allows rapid damage assessment over the area of interest. Rice yield monitoring is based on a crop growth simulation and SAR-derived key information, particularly start of season and leaf growth rate. Results from pilot study sites in South and South East Asian countries suggest that incorporation of SAR data into crop model improves yield estimation for actual yields. Remote-sensing data assimilation into crop model effectively capture responses of rice crops to environmental conditions over large spatial coverage, which otherwise is practically impossible to achieve. Such improvement of actual yield estimates offers practical application such as in a crop insurance program. Process-based crop simulation model is used in the system to ensure climate information is adequately captured and to enable mid-season yield forecast.

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

    CERN Document Server

    Farazmand, Mohammad

    2015-01-01

    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.

  11. A WEB BASED TOMATO CROP EXPERT INFORMATION SYSTEM BASED ON ARTIFICIAL INTELLIGENCE AND MACHINE LEARNING ALGORITHMS

    OpenAIRE

    Prasad Babu M.S; Ramana Murty .N.V; Narayana S.V.N.L

    2010-01-01

    Tomato is now the most widely grown vegetable crop in World. It is grown throughout the world in farm gardens, small home-gardens, and by market gardeners for fresh consumption as well as for processingpurposes. This Tomato crop expert advisory system is aimed at a collaborative venture with eminent Agriculture Scientist and Experts in the area of Tomato Plantation with an excellent team of computer Engineers, programmers and designers. This Expert System contains two main parts one is Tomato...

  12. PARÁMETROS HIDRÁULICOS DETERMINADOS EN UN ANDISOL BAJO DIFERENTES ROTACIONES CULTURALES DESPUÉS DE DIEZ AÑOS Hydraulic parameters determinated in Andisol under different crop rotations after ten years

    Directory of Open Access Journals (Sweden)

    Marco Sandoval E

    2007-01-01

    Full Text Available Los parámetros Hidráulicos fueron medidos en un suelo de origen volcánico del Valle Central (Humic Haploxerands bajo diferentes rotaciones culturales con distinto manejo agronómico e intensidad de uso del suelo y fueron agrupadas en cuatro rotaciones que incluyeron pradera y dos rotaciones intensivas, sin pradera. Las mediciones de conductividad Hidráulica saturada (Kfs fueron realizadas in-situ. Se determinaron, además, dos parámetros Hidráulicos del suelo: El parámetro á y el potencial de flujo mátrico (?m. Todas las parcelas con pradera, dentro de la rotación tuvieron valores similares de Kfs. Las parcelas con rotaciones intensivas presentaron valores extremos el mayor y menor valor de Kfs, donde la rotación: remolacha-trigo-frejol-cebada, presentó el mayor Kfs (P?0,05 de todos los tratamientos. Nuestros resultados fueron apoyados por un análisis de correlación en que se determinó una significativa (P?0,05 relación entre Kfs y los parámetros Hidráulicos y potencial de flujo mátrico (?m.Hydraulic parameters were measured in a soil of volcanic origin of the Central Valley (Humic Haploxerands under different crop rotations with different agricultural management and soil-use intensity that were grouped in four rotations that included pastures and two intensive rotations without pastures. Measurements of saturated hydraulic conductivity (Ka were done in-situ. At the mean time, two hydraulic parameters of soil were determined: á parameter and matric flux potential (?m. All plots with pasture included in the rotation had similar mean Kfs values. The plots with intensive rotations had the extreme, the Highes and lower Kfs values. The Kfs in the rotation sugar beet-wheat-beans-barley was the Highest Kfs (P?0,05 of all treatments. Our results were supported by a correlation analysis that determined significant relationships (P?0,05 between Kfs, and the hydraulic parameters a and matric flux potential (?m

  13. Irrigation capacity impact on limited irrigation management and cropping systems

    Science.gov (United States)

    Irrigation capacity in corn production is an increasingly important issue in the semi-arid Great Plains as irrigation well outputs decrease to the point where fully meeting crop water needs is not possible. Strategies need to be developed that will maximize yields under reduced water application amo...

  14. Possible impact of the Renewable Energy Directive on N fertilization intensity and yield of winter oilseed rape in different cropping systems

    International Nuclear Information System (INIS)

    In 2009, the Renewable Energy Directive (RED), established sustainability criteria for biofuels including legal thresholds for specific greenhouse gas (GHG) emissions, expressed as g CO2eq per MJ of biofuel. Because biofuels are a major market for winter oilseed rape (WOSR), investigating the possible impact of the RED on WOSR cropping practices is prudent. This study analyses GHG emissions for WOSR cropping practices (namely N fertilization intensity, tillage method and crop rotation) basing on a 6-year field trial in a high yielding area of northern Germany. Using the International Panel on Climate Change (IPCC) methodology the field emissions of nitrous oxide (N2O) are calculated from the nitrogen (N) inputs to the cropping system. Results showed that the predominant source of GHG emissions is the N related emissions from production of fertilizer and N2O field emissions. Specific GHG emissions are lowest without N fertilizer but rise continuously with increasing N rates. Yield per ha also responded to N fertilization resulting in lowered acreage productivity when reducing GHG emissions by reducing N fertilization level. Most calculated scenarios and cropping systems result in a drastic decrease of N fertilization to achieve thresholds, causing substantial yield losses. To a certain extent, the required drastic reduction of N fertilization in some scenarios is driven by using the IPCC methodology for calculating N2O emissions. Therefore characteristics of this methodology are also discussed within this study. To mitigate the impact of the RED on WOSR, peas (legumes) may be a possible preceding crop to WOSR. -- Highlights: •Greenhouse gas emissions (GHG) were calculated for varying cropping systems. •Specific GHG emissions rise continuously with increasing N fertilization. •The impact of the Renewable Energy Directive was evaluated in a scenario analysis. •Most calculation scenarios require a substantial reduction of N fertilization. •Low N fertilization results in drastic yield losses and low acreage productivity

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

    International Nuclear Information System (INIS)

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

  16. Performance of the CELSS Antarctic Analog Project (CAAP) crop production system

    Science.gov (United States)

    Bubenheim, D. L.; Schlick, G.; Wilson, D.; Bates, M.

    2003-01-01

    Regenerative life support systems potentially offer a level of self-sufficiency and a decrease in logistics and associated costs in support of space exploration and habitation missions. Current state-of-the-art in plant-based, regenerative life support requires resources in excess of allocation proposed for candidate mission scenarios. Feasibility thresholds have been identified for candidate exploration missions. The goal of this paper is to review recent advances in performance achieved in the CELSS Antarctic Analog Project (CAAP) in light of the likely resource constraints. A prototype CAAP crop production chamber has been constructed and operated at the Ames Research Center. The chamber includes a number of unique hardware and software components focused on attempts to increase production efficiency, increase energy efficiency, and control the flow of energy and mass through the system. Both single crop, batch production and continuous cultivation of mixed crops production studies have been completed. The crop productivity as well as engineering performance of the chamber are described. For each scenario, energy required and partitioned for lighting, cooling, pumping, fans, etc. is quantified. Crop production and the resulting lighting efficiency and energy conversion efficiencies are presented. In the mixed-crop scenario, with 27 different crops under cultivation, 17 m2 of crop area provided a mean of 515 g edible biomass per day (85% of the approximate 620 g required for one person). Enhanced engineering and crop production performance achieved with the CAAP chamber, compared with current state-of-the-art, places plant-based life support systems at the threshold of feasibility. c2002 Published by Elsevier Science Ltd on behalf of COSPAR.

  17. Nitrogen balance and groundwater nitrate contamination: comparison among three intensive cropping systems on the North China Plain.

    Science.gov (United States)

    Ju, X T; Kou, C L; Zhang, F S; Christie, P

    2006-09-01

    The annual nitrogen (N) budget and groundwater nitrate-N concentrations were studied in the field in three major intensive cropping systems in Shandong province, north China. In the greenhouse vegetable systems the annual N inputs from fertilizers, manures and irrigation water were 1358, 1881 and 402 kg N ha(-1) on average, representing 2.5, 37.5 and 83.8 times the corresponding values in wheat (Triticum aestivum L.)-maize (Zea mays L.) rotations and 2.1, 10.4 and 68.2 times the values in apple (Malus pumila Mill.) orchards. The N surplus values were 349, 3327 and 746 kg N ha(-1), with residual soil nitrate-N after harvest amounting to 221-275, 1173 and 613 kg N ha(-1) in the top 90 cm of the soil profile and 213-242, 1032 and 976 kg N ha(-1) at 90-180 cm depth in wheat-maize, greenhouse vegetable and orchard systems, respectively. Nitrate leaching was evident in all three cropping systems and the groundwater in shallow wells (requirements and the excessive fertilizer N inputs were only about 40% of total N inputs. PMID:16364521

  18. Controlled Drainage As Measure to Reduce Nitrate Leaching in a Wheat Cropping System

    DEFF Research Database (Denmark)

    BØrgesen, Christen Duus; Hvid, SØren Kolind

    2013-01-01

    Subsurface drainage of soil to avoid water logging is a prerequisite for crop cultivation for a large proportion of the agricultural land, and approximately 50% of the Danish agricultural area is artificially drained. Multifunctional drain systems can be effective measures to reduce losses of nutrients, such as Controlled Drainage (CD). With CD the water table of drained fields is raised or lowered by adjusting the drain pipe outlet elevation. By restricting drain flow at times when drainage is not needed, the overall volume of water flow is reduced, more soil moisture is available for the growing crop, and nutrient exports are reduced. CD has been shown to diminish leaching losses of soluble nutrients. So far CD has only been tested for spring sown crops but widespread implementation on drained clayey soils would rely on its adaption to winter cereal production systems. A new project on CD applied at four winter cropped fields in Denmark investigates how effects of anaerobic conditions created by CD will affect chemical/biological processes in the submerged soil, root growth, crop production, and nutrient losses. Nitrification is expected to be retarded by wet soils during winter, preserving ammonium for crop uptake in the following cropping season. Installed equipment, soil survey results and measurement results from the first winter season will be presented.

  19. Analytical steady-state solutions for water-limited cropping systems using saline irrigation water

    Science.gov (United States)

    Skaggs, T. H.; Anderson, R. G.; Corwin, D. L.; Suarez, D. L.

    2014-12-01

    Due to the diminishing availability of good quality water for irrigation, it is increasingly important that irrigation and salinity management tools be able to target submaximal crop yields and support the use of marginal quality waters. In this work, we present a steady-state irrigated systems modeling framework that accounts for reduced plant water uptake due to root zone salinity. Two explicit, closed-form analytical solutions for the root zone solute concentration profile are obtained, corresponding to two alternative functional forms of the uptake reduction function. The solutions express a general relationship between irrigation water salinity, irrigation rate, crop salt tolerance, crop transpiration, and (using standard approximations) crop yield. Example applications are illustrated, including the calculation of irrigation requirements for obtaining targeted submaximal yields, and the generation of crop-water production functions for varying irrigation waters, irrigation rates, and crops. Model predictions are shown to be mostly consistent with existing models and available experimental data. Yet the new solutions possess advantages over available alternatives, including: (i) the solutions were derived from a complete physical-mathematical description of the system, rather than based on an ad hoc formulation; (ii) the analytical solutions are explicit and can be evaluated without iterative techniques; (iii) the solutions permit consideration of two common functional forms of salinity induced reductions in crop water uptake, rather than being tied to one particular representation; and (iv) the utilized modeling framework is compatible with leading transient-state numerical models.

  20. Cultivo de milho no sistema de aléias com leguminosas perenes Maize crop in alley cropping system with perennials legumes

    Directory of Open Access Journals (Sweden)

    Luciano Rodrigues Queiroz

    2007-10-01

    Full Text Available Objetivou-se avaliar a influência de algumas leguminosas perenes no teor foliar de N, P e K e na produtividade da cultura do milho (UENF 506-8, cultivado no sistema de aléias, sem adubação fosfatada. Foram realizados experimentos de campo por dois ciclos de cultivo, no Campo Experimental do CCTA/UENF, em Campos dos Goytacazes - RJ. Os tratamentos consistiram no sistema de aléias com Albizia lebbeck (L. Benth., Peltophorum dubium (Spreng. Taub., Leucaena leucocephala (Lam. de Wit., Cajanus cajan (L. Millsp., Sesbania virgata (Cav. Pers., Mimosa caesalpiniaefolia Benth., Gliricidia sepium (Jacq. Pers. e duas testemunhas com milho solteiro (com e sem NPK. Após oito meses de plantio das leguminosas, essas foram podadas, o material foi incorporado ao solo e em seguida semeado o milho nas entrelinhas, com espaçamento de 80 cm entre fileiras. Após 60 dias da semeadura do milho efetuou-se nova poda. No segundo ciclo de cultivo, as práticas culturais foram similares às do primeiro. Foi utilizado o delineamento em blocos casualizados com quatro repetições. Nas aléias de guandu, observou-se milho com maior teor foliar de N, em relação às demais leguminosas, no primeiro ciclo de cultivo. No segundo ciclo, os consórcios milho+guandu, milho+gliricídia e milho solteiro adubado superaram os demais na produtividade de grãos.The objective of this study was to evaluate the effects of perennials legumes, in N, P and K foliar concentration and maize productivity in alley cropping system, without phosphorus fertilization. Field experiments were carried out for two cycles, with legumes intercropping maize (UENF 506-8 in Field Research CCTA/UENF in Campos dos Goytacazes - RJ - Brazil. The treatments consisted of alley cropping system with the species: Albizia lebbeck (L. Benth., Peltophorum dubium (Spreng. Taub., Leucaena leucocephala (Lam. de Wit., Cajanus cajan (L. Millsp., Sesbania virgata (Cav. Pers., Mimosa caesalpiniaefolia Benth., Gliricidia sepium (Jacq. Pers. and two control treatments: sole maize with or without fertilizer NPK. Eight months after the plantation, the legumes species were pruned and incorporated in soil. Maize was sown interows legumes, in rows spaced 80 cm. New prune carried on sixty days after the first cut. In the second cycle, the crop handlings were similar to the first cycle. The experimental design consisted of randomized blocks with four replicates. In the alley cropping with Cajanus cajan the maize show the larger N foliar concentration, in first cycle. In the second cycle, maize+Gliricidia sepium, maize+Cajanus cajan and sole maize with NPK produced more grain than others treatments.

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

    DEFF Research Database (Denmark)

    Askegaard, Margrethe; Thomsen, Ingrid Kaag

    2011-01-01

    In order to obtain a high and stable yield of organic spring barley, production should be optimized according to the specific environment. To test the performance of spring barley varieties under varying cropping conditions, a field experiment was carried out in 2003 and 2004 in a six-field mixed organic crop rotation. We investigated the choice of variety, the order in a rotation, and the application of manure (slurry and farmyard manure; 0 to 120 total-N ha?1) on grain yields of six selected varieties with different characteristics grown in either pure stands or in two spring barley mixtures, each consisting of three varieties. Average grain yield of the barley varieties varied between 3.3 t DM ha?1 and 4.1 t DM ha?1. Grain yields of the two mixtures were 4.0 and 3.6 t DM ha?1, respectively. The varieties/mixtures interacted with crop order and year. Foliar diseases were more severe in the barley following grass-clover with large annual differences in the individual diseases. Despite different rooting depths and nutrient uptake patterns, there was no interaction between variety/mixture and the manure input regarding grain yield. In the 1st year after grass-clover, one of the two mixtures gave higher grain yield than the average yield of the individual varieties in the mixture. This was not the case in the 4th year after grass-clover and for the second variety mixture. Thus, although the present results did not indicate that some barley varieties were better adapted to conditions with low manure input than others, variety mixtures that give a robust and stable organic production may potentially be developed.

  2. Nine-year results on maize and processing tomato cultivation in an organic and in a conventional low input cropping system

    Directory of Open Access Journals (Sweden)

    Marcello Guiducci

    2013-02-01

    Full Text Available Nine-year results on yields and apparent balances of organic matter and nitrogen (N are reported for maize and processing tomato cultivated in a long term comparison trial between an organic and a conventional low-input system in Central Italy. In every year, above ground biomass and N accumulation of each cash crop and green manure, including weeds, and the partitioning between marketable yield and crop residues were determined. Apparent dry matter and nitrogen balances were calculated at the end of each crop cycle by taking into account the amounts of dry matter and ex-novo N supplied to the system as green manure legume Ndfa (i.e. an estimate of N derived from the atmosphere via symbiotic fixation and fertilizers, and those removed with marketable yield. Processing tomato complied with organic cultivation better than maize. As compared to the conventional crop cultivation, organic tomato provided similar yields, used supplied N more efficiently and left lower residual N after harvest, with lower related risks of pollution. Organic maize yielded less than conventional one. The main limitation for organic maize was the low N availability during initial growth phases, due to either low N supply or low rate of N release from incorporated green manure biomass. In both organic and conventional cultivation the system sustainability could be improved by an appropriate crop rotation: wheat in fall winter likely prevented leaching loss of mineral N in both systems; green manure crops in the organic system allowed to either trap and recycle soil mineral N or supply ex novo legume Ndfa to the soil, with benefits in mitigation of N pollution and improvement in self-sufficiency of the system.

  3. Oscillating and rotating sine-Gordon system

    DEFF Research Database (Denmark)

    Olsen, O. H.; Samuelsen, Mogens Rugholm

    1986-01-01

    The interaction between a 2? kink and the background or vacuum is investigated in the pure sine-Gordon system. For an oscillating background (i.e., the k=0 part of the phonon spectrum) the 2? kink oscillates, while for increasing or decreasing vacuum two phenomena have been observed, depending on the rate of change of the vacuum. For small rates a parametric excitation of standing waves is found, and for larger rates the system linearizes. In the case of oscillating vacuum a perturbation approach explains the behavior perfectly, while for small rates of increasing vacuum the system reduces to a Mathieu equation explaining the excitation.

  4. Crop yield network and its response to changes in climate system

    Science.gov (United States)

    Yokozawa, M.

    2013-12-01

    Crop failure (reduction in crop yield) due to extreme weather and climate change could lead to unstable food supply, reflecting the recent globalization in world agricultural production. Specifically, in several major production countries producing large amount of main cereal crops, wheat, maize, soybean and rice, abrupt crop failures in wide area are significantly serious for world food supply system. We examined the simultaneous changes in crop yield in USA, China and Brazil, in terms of the changes in climate system such as El Nino, La nina and so on. In this study, we defined a crop yield networks, which represent the correlation between yearly changes in crop yields and climate resources during the crop growing season in two regions. The climate resources during the crop growing season represents here the average temperature and the accumulated precipitation during the crop growing season of a target crop. As climate data, we used a reanalysis climate data JRA-25 (Japan Meteorological Agency). The yearly changes in crop yields are based on a gridded crop productivity database with a resolution of 1.125 degree in latitude/longitude (Iizumi et al. 2013). It is constructed from the agriculture statistics issued by local administrative bureau in each country, which covers the period during 1982 to 2006 (25 years). For the regions being lack of data, the data was interpolated referring to NPP values estimated by satellite data. Crop yield network is constructed as follows: (1) let DY(i,y) be negative difference in crop yield of year y from the trend yield at grid i; (2) define the correlation of the differences Cij(y) = DY(i, y) DY(j, y); (3) if Cij(y) > Q, then grids i and j are mutually linked for a threshold value Q. Links between grids make a crop yield network. It is here noted that only negative differences are taken into account because we focused on the lean year cases (i.e. yields of both grids were lower than those in the long-term trend). The arrays of correlation function Cij(y) construct the adjacent matrix of year y for the network. That is, non zero elements of the matrix mean that there occurred yield reduction at the corresponding grids at year y. When the number of non zero elements is large, it indicates that simultaneous yield reduction occurred in broad area in the country. We firstly examined the time changes of link density, which is defined as the ratio of the number of non zero elements to that of all the elements (=n(n+1)/2, where n denotes the number of grids), in terms of climate variability. As the results, the link density of crop yield network for maize in USA was about 0.4 as the mean and changed temporally larger than that in China in the past years, which in China was about 0.3 as the mean for the past 25 years (1982-2006). To examine the relationship climate variability and time changes in link density, we conducted multiple regression analysis taking the link density as a dependent variable and SOI indices of the preceding months before harvest (October) as the independent variables. It is shown that the link density for the crop yield network of maize in China could be significantly correlated with the SOI indices on February, August and September. For the crop yield network of maize in USA, no significant correlation was found.

  5. 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.

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

    Science.gov (United States)

    Lee, Sang-Hee

    2012-12-01

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

  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. Emergy analysis of cropping-grazing system in Inner Mongolia Autonomous Region, China

    International Nuclear Information System (INIS)

    An ecological energetic evaluation is presented in this paper as a complement to economic account for the cropping-grazing system in the Inner Mongolia Autonomous Region in China in the year 2000. Based on Odum's well-known concept of emergy in terms of embodied solar energy as a unified measure for environmental resources, human or animal labors and industrial products, a systems diagram is developed for the crop and livestock productions with arms and sub-arms for free renewable natural resource input, purchased economic investment, yields of and interactive fluxes between the cropping and grazing sub-industries. In addition to conventional systems indices of the emergy yield ratio (EYR), emergy investment ratio (EIR), environmental load ratio (ELR) and environmental sustainability index (ESI) introduced for congregated systems ecological assessment with essential implication for sustainability, new indicators of soil emergy cost (SEC), self-support intensity (SSI) and self-support orientation (SSO) are defined to characterize the desertification and internal recycling associated with the special agricultural system. Extensive emergy accounting is made for the cropping-grazing system as a whole as well as for the cropping and grazing subsystems. The overall cropping-grazing system is shown with outstanding production competence compared with agricultural systems in some other provinces and the national average in China, though confronted with severe desertification gh confronted with severe desertification associated with soil loss. The production of crops has higher emergy density and yield rate per unit area as well as higher rate of soil loss than grazing system. The soil emergy cost defined as the soil loss emergy divided by the yield emergy is estimated to be of the same value for both of the subsystems, but the grazing activity is with less extraction intensity, leaving rangeland to rest and rehabilitate. Suggestions with regard to the local sustainability and national ecological security in northern China are explored for land-use policy making

  9. Emergy analysis of cropping-grazing system in Inner Mongolia Autonomous Region, China

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, L.X. [National Laboratory for Environmental Simulation and Pollution Control, School of Environmental Sciences, Beijing Normal University, Beijing 100875 (China); Yang, Z.F. [National Laboratory for Environmental Simulation and Pollution Control, School of Environmental Sciences, Beijing Normal University, Beijing 100875 (China); Chen, G.Q. [National Laboratory for Complex Systems and Turbulence, Department of Mechanics, Peking University, Beijing 100871 (China)]. E-mail: gqchen@pku.edu.cn

    2007-07-15

    An ecological energetic evaluation is presented in this paper as a complement to economic account for the cropping-grazing system in the Inner Mongolia Autonomous Region in China in the year 2000. Based on Odum's well-known concept of emergy in terms of embodied solar energy as a unified measure for environmental resources, human or animal labors and industrial products, a systems diagram is developed for the crop and livestock productions with arms and sub-arms for free renewable natural resource input, purchased economic investment, yields of and interactive fluxes between the cropping and grazing sub-industries. In addition to conventional systems indices of the emergy yield ratio (EYR), emergy investment ratio (EIR), environmental load ratio (ELR) and environmental sustainability index (ESI) introduced for congregated systems ecological assessment with essential implication for sustainability, new indicators of soil emergy cost (SEC), self-support intensity (SSI) and self-support orientation (SSO) are defined to characterize the desertification and internal recycling associated with the special agricultural system. Extensive emergy accounting is made for the cropping-grazing system as a whole as well as for the cropping and grazing subsystems. The overall cropping-grazing system is shown with outstanding production competence compared with agricultural systems in some other provinces and the national average in China, though confronted with severe desertification associated with soil loss. The production of crops has higher emergy density and yield rate per unit area as well as higher rate of soil loss than grazing system. The soil emergy cost defined as the soil loss emergy divided by the yield emergy is estimated to be of the same value for both of the subsystems, but the grazing activity is with less extraction intensity, leaving rangeland to rest and rehabilitate. Suggestions with regard to the local sustainability and national ecological security in northern China are explored for land-use policy making.

  10. Rotating solid radiative coolant system for space nuclear reactors

    Energy Technology Data Exchange (ETDEWEB)

    Apley, W.J.; Babb, A.L.

    1988-05-01

    The RING power system described in this paper is proposed as a primary or emergency heat rejection system for advanced space reactor power applications. The system employs a set of four (4) counter-rotating, 90 degree offset, coolant-carrying rings. The rings (segmented, corrugated, finned, thin-walled pipes, filled with liquid lithium) pass through a cavity heat exchanger and reradiate the absorbed heat to the space environment. 25 refs., 6 figs., 3 tabs.

  11. Analysis and modelling of rotational systems with the Modyfit application

    OpenAIRE

    Z?o??kiewski, S.

    2008-01-01

    Purpose: of this article is to present an application to analysis and modelling of rotational systems. Independent modules of application enables controlling and regulation of characteristics of systems in transportation. The base problem of analyzing systems in transportation is expressing the interaction between the main motion and local vibrations of subsystems.Design/methodology/approach: Mathematical models derived in previous articles were used to implement the mathematical mo...

  12. Share of anthropophytes in the crop sequence: winter wheat – maize – spring wheat depending on tillage system

    Directory of Open Access Journals (Sweden)

    Tomasz R. Sekutowski

    2014-07-01

    Full Text Available An experiment, conducted over the period 2008–2010, evaluated the effect of tillage system on the occurrence and species composition of anthropophytes in winter wheat, maize and spring wheat. Regardless of crop plant and tillage system, anthropophytes (73.9%, represented by archaeophytes and kenophytes, were the main component of the flora in the crops studied, whereas apophytes accounted for the remaining 26.1%. Most archaeophytes (13 species were found in the spring wheat crop under no-tillage, while their lowest number (6 species occurred in the spring wheat crop under conventional tillage. The only kenophyte, Conyza canadensis, was found to occur in the spring wheat and maize crops in the no-tillage system. The following taxa were dominant species among archeophytes: Geranium pusillum, Anthemis arvensis, and Viola arvensis (regardless of tillage system and crop plant, Anthemis arvensis (in spring wheat – conventional tillage, Echinochloa crus-galli and Setaria glauca (in maize – reduced tillage and no-tillage, Chenopodium album (in maize – no-tillage as well as Apera spica-venti, Anthemis arvensis and Papaver rhoeas (in winter wheat – no-tillage.

  13. Review of intercropping research: Studies on cereal-vegetable based cropping system

    Directory of Open Access Journals (Sweden)

    M.O. Ijoyah

    2012-11-01

    Full Text Available Intercropping which is closely associated with peasant agriculture is a practice that involves the growth of two or more crops in proximity, in the same field during a growing season to promote interactions between them. Reasons for this practice include insurance against total crop failure, yield increment, weed control and high monetary returns. Studies on crop mixture have recently focused on cereal-vegetable intercropping system, such as maize-okra, maize-tomato, maize-leafy green, maize-egusi melon, maize-cauliflower amongst others. This paper, which is a compilation of reviewed reports, generally examined the areas of consideration in intercropping, it discussed the benefits obtained and broadly assessed the yield advantages derived from intercropping, with particular reference to cereal-vegetable based cropping system. The compilation of the reviewed reports, therefore serves as useful information base for other agricultural scientists with interest in the area of intercropping research, with particular focus on cereal-vegetable mixture.

  14. A Hybrid Neural Network Method for Detecting Structural Change in Oil-Bioenergy Crops Prices System

    Directory of Open Access Journals (Sweden)

    Yu Zhao

    2012-09-01

    Full Text Available The present study detects the structural change in oil-bioenergy crops prices system before and during the food crisis of 2007/2008 and financial crisis 2008/2010. In the recent years, rising world crude oil prices lead to increase of bioenergy production around the world. Bioenergy, in turn, affects bioenergy crops price, because it uses these commodities as inputs. We develop a hybrid neural network approach which can test the structural change of the linkages without priori knowledge of the input data distribution. And then we studies price linkages applying the hybrid neural network to two major bioenergy crops prices, including Argentina corn and Brazil soybean, along with two major crude oil price, including West Texas and Brant crude oil. The data consists of 1467 observations from January 2006 to November 2011. The empirical findings confirm that the structures of oil-bioenergy crops prices system change observably during the food crisis and the financial crisis.

  15. A crop population perspective on maize seed systems in Mexico

    OpenAIRE

    Dyer, George A.; Taylor, J. Edward

    2008-01-01

    Improvement of local germplasm through artificial selection is regarded as the main force behind maize evolution and diversity in Mexico, the crop's center of origin. This perspective neglects the larger social context of maize evolution. Using a theoretical approach and Mexico-wide data, we show that farmer-led evolution of maize is largely driven by a technological diffusion and appropriation process that selectively integrates nonlocal germplasm into local seed stocks. Our approach constru...

  16. Prototype Geographic Information Systems Mapping of Crop Products Featured Local

    OpenAIRE

    Teddy Oswari; Euphrasia Susy Suhendra; Emy Haryatmi; Fenni Agustina

    2013-01-01

    Local featured program in Indonesia cannot be separated entirely from commodity strategic bases. Until in 2006, agricultural development formulation showed indicative targets for featured crops commodity production. The problem of food security is forming of farmer’s independence to protect local resources in efficiently and optimally, so these resources can be more utilized. It can be achieved by assist of information technologies and communication in forming of Geographic Information Sys...

  17. Multi-crop Chlorophyll Meter System Design for Effective Fertilization

    Directory of Open Access Journals (Sweden)

    S. Maheswaran

    2015-01-01

    Full Text Available The aim of this article is to design a key device for the management of Nitrogen (N concentration in the crops for an effective yield. In leaves, the chlorophyll content is estimated through the chlorophyll meter which detects the optical signal (light between the wavelengths 450 nm and 950 nm. The received optical light in each wavelengths are determined. Chlorophyll takes 425-450 nm optical signals and consequently, the acquired of the wavelengths penetrating through the leaves is diminished if it is compared with the reception of 650-670 nm light. The light of 950 nm wavelength is uninterrupted due to chlorophyll level in the leaves and the received light acts as an indicator to determine the hairy or waxy presence on the surface of the leaves. In the test field, major methods find out the collection of N status, processing, soil analysis and the samples of plant tissue but with the help of handy chlorophyll meter, the level of chlorophyll as well the N availability can be predicted on several crops. By using an 8 bit microcontroller, light emitting diode, photo diode and amplifier, the leaf chlorophyll content has been measured for different crops like turmeric, sugar cane and plantain etc. Field measurement manifests nitrogen content in terms of percentage as shown in 6 levels of Leaf Colour Chart (LCC. And also infers that chlorophyll absorbs more at 425-450 nm than 650-670 nm light.

  18. A Hybrid Neural Network Method for Detecting Structural Change in Oil-Bioenergy Crops Prices System

    OpenAIRE

    Yu Zhao; Yu Zhang; Hong Xu

    2012-01-01

    The present study detects the structural change in oil-bioenergy crops prices system before and during the food crisis of 2007/2008 and financial crisis 2008/2010. In the recent years, rising world crude oil prices lead to increase of bioenergy production around the world. Bioenergy, in turn, affects bioenergy crops price, because it uses these commodities as inputs. We develop a hybrid neural network approach which can test the structural change of the linkages without priori knowledge of th...

  19. A GPS Backpack System for Mapping Soil and Crop Parameters in Agricultural Fields

    Science.gov (United States)

    Stafford, J. V.; Lebars, J. M.

    Farmers are having to gather increasing amounts of data on their soils and crops. Precision agriculture metre-by-metre is based on a knowledge of the spatial variation of soil and crop parameters across a field. The data has to be spatially located and GPS is an effective way of doing this. A backpack data logging system with GPS position tagging is described which has been designed to aid a fanner in the manual collection of data.

  20. 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)

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

    Scientific Electronic Library Online (English)

    Juliano Carlos, Calonego; Ciro Antonio, Rosolem.

    2011-06-01

    Full Text Available A disponibilidade de água às plantas é alterada pela compactação do solo e outras variáveis. O Intervalo Hídrico Ótimo (IHO) integra variáveis físicas do solo que alteram o crescimento radicular e a disponibilidade de água e pode ser manejado por métodos mecânicos ou biológicos. Há evidências de que [...] os efeitos da rotação de culturas são mais duradouros que os da escarificação. O objetivo deste trabalho foi avaliar o efeito da escarificação e, ou, rotação de culturas em sistema de semeadura direta (SSD) no IHO. Rotações envolvendo triticale (X Triticosecale) e girassol (Helianthus annuus) no outono-inverno e milheto (Pennisetum glaucum), sorgo (Sorghum bicolor) e crotalária (Crotalaria juncea) com plantas de cobertura precedendo a soja (Glycine max) foram repetidas por três anos. No tratamento com escarificação, a área foi deixada em pousio entre as culturas de outono-inverno e verão. O experimento foi conduzido em Botucatu, São Paulo, Brasil, de 2003 a 2006 em um Nitossolo Vermelho. O IHO foi determinado em amostras de solo das profundidades de 0-20 e 20-40 cm, logo após a dessecação química das plantas de cobertura, em dezembro do primeiro e do terceiro ano do experimento. A escarificação diminui a densidade do solo na camada de 0-20 cm, aumentando o IHO por meio da redução da umidade do solo em que a resistência à penetração atinge 2,0 MPa; esse efeito mantém-se até o terceiro ano após a escarificação, podendo chegar a até 40 cm de profundidade. As rotações de culturas envolvendo girassol + crotalária, triticale + milheto e triticale + crotalária por três anos ajudaram a prevenir o aumento na densidade do solo acima do valor crítico na camada de 0-20 cm. Esse efeito é observado na camada de 20- 40 cm após três anos da escarificação e com rotações de culturas envolvendo sorgo. Assim, a escarificação e algumas rotações de culturas em sistema de semeadura direta são eficientes em melhorar a qualidade do solo avaliada pelo IHO. Abstract in english 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 effec [...] ts 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. Integrating livestock manure with a corn-soybean bioenergy cropping system improves short-term carbon sequestration rates and net global warming potential

    International Nuclear Information System (INIS)

    Carbon cycling and the global warming potential (GWP) of bioenergy cropping systems with complete biomass removal are of agronomic and environmental concern. Corn growers who plan to remove corn stover as a feedstock for the emerging cellulosic ethanol industry will benefit from carbon amendments such as manure and compost, to replace carbon removed with the corn stover. The objective of this research was to determine the effect of beef cattle feedlot manure and composted dairy manure on short-term carbon sequestration rates and net global warming potential (GWP) in a corn-soybean rotation with complete corn-stover removal. Field experiments consisting of a corn-soybean rotation with whole-plant corn harvest, were conducted near East Lansing, MI over a three-year period beginning in 2002. Compost and manure amendments raised soil carbon (C) at a level sufficient to overcome the C debt associated with manure production, manure collection and storage, land application, and post-application field emissions. The net GWP in carbon dioxide equivalents for the manure and compost amended cropping systems was -934 and -784 g m-2 y-1, respectively, compared to 52 g m-2 y-1 for the non-manure amended synthetic fertilizer check. This work further substantiates the environmental benefits associated with renewable fuels and demonstrates that with proper management, the integration of livestock manures in biofuel cropping systems can enhance greenhouse gas (GHG) remediation.

  3. Integrating livestock manure with a corn-soybean bioenergy cropping system improves short-term carbon sequestration rates and net global warming potential

    Energy Technology Data Exchange (ETDEWEB)

    Thelen, K.D.; Fronning, B.E.; Kravchenko, A.; Min, D.H.; Robertson, G.P. [Michigan State University, East Lansing, MI 48824 (United States)

    2010-07-15

    Carbon cycling and the global warming potential (GWP) of bioenergy cropping systems with complete biomass removal are of agronomic and environmental concern. Corn growers who plan to remove corn stover as a feedstock for the emerging cellulosic ethanol industry will benefit from carbon amendments such as manure and compost, to replace carbon removed with the corn stover. The objective of this research was to determine the effect of beef cattle feedlot manure and composted dairy manure on short-term carbon sequestration rates and net global warming potential (GWP) in a corn-soybean rotation with complete corn-stover removal. Field experiments consisting of a corn-soybean rotation with whole-plant corn harvest, were conducted near East Lansing, MI over a three-year period beginning in 2002. Compost and manure amendments raised soil carbon (C) at a level sufficient to overcome the C debt associated with manure production, manure collection and storage, land application, and post-application field emissions. The net GWP in carbon dioxide equivalents for the manure and compost amended cropping systems was -934 and -784 g m{sup -2} y{sup -1}, respectively, compared to 52 g m{sup -2} y{sup -1} for the non-manure amended synthetic fertilizer check. This work further substantiates the environmental benefits associated with renewable fuels and demonstrates that with proper management, the integration of livestock manures in biofuel cropping systems can enhance greenhouse gas (GHG) remediation. (author)

  4. Catch crop biomass production, nitrogen uptake and root development under different tillage systems

    DEFF Research Database (Denmark)

    Munkholm, Lars Juhl; Hansen, Elly MØller

    2012-01-01

    Catch crops are generally regarded as an efficient tool to reduce nitrate leaching. However, the benefits need to be balanced against potential adverse effects on the main crop yields. The objectives of the study were to study three contrasting catch crops, that is, dyer’s woad (DW) (Isatis tinctoria L.), perennial ryegrass (RG) (Lolium perenne L.) and fodder radish (FR) (Raphanus sativus L.) under three tillage systems. For that, we used a tillage experiment established in 2002 on a Danish sandy loam. The tillage treatments were direct drilling (D), harrowing to 8–10 cm (H) and ploughing (P). Above-ground biomass production and N uptake were measured in the catch crops and the main crop. Catch crop root growth was studied using both minirhizotron and core methods. Soil penetration resistance was recorded to 60 cm depth. Fodder radish and RG produced up to 1800 kg/ha dry matter and DW 900 kg/ha. The nitrogen uptake in November was 55, 37 and 31 kg N/ha for FR, RG and DW, respectively, when averaged across the2 yr of study. The yield of the spring barley main crop was in general highest where FR was grown as a catch crop. Ploughing tended to result in highest yields although differences were only significant in 2008. The minirhizotron root measurements showed that the crucifers FR and DW achieved better subsoil rooting than RG. In contrast, the soil core data showed no significant difference between FR and RG in subsoil root growth. Our study highlights the need for further studies on subsoil root growth of different catch crops.

  5. 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...

  6. Influence of Different Tillage Systems and Weed Treatments in the Establishment Year on the Final Biomass Production of Short Rotation Coppice Poplar

    OpenAIRE

    Heinrich Spiecker; Frieder Seidl; Jonathan Sheppard; Christop