WorldWideScience

Sample records for leaving crop residue

  1. Soil water evaporation and crop residues

    Science.gov (United States)

    Crop residues have value when left in the field and also when removed from the field and sold as a commodity. Reducing soil water evaporation (E) is one of the benefits of leaving crop residues in place. E was measured beneath a corn canopy at the soil suface with nearly full coverage by corn stover...

  2. Alternatives to crop residues for soil amendment

    OpenAIRE

    Powell, J.M.; Unger, P.W.

    1997-01-01

    Metadata only record In semiarid agroecosystems, crop residues can provide important benefits of soil and water conservation, nutrient cycling, and improved subsequent crop yields. However, there are frequently multiple competing uses for residues, including animal forage, fuel, and construction material. This chapter discusses the various uses of crop residues and examines alternative soil amendments when crop residues cannot be left on the soil.

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

    Science.gov (United States)

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

  4. Recycling crop residues for use in recirculating hydroponic crop production

    Science.gov (United States)

    Mackowiak, C. L.; Garland, J. L.; Sager, J. C.

    1996-01-01

    As part of bioregenerative life support feasibility testing by NASA, crop residues are being used to resupply elemental nutrients to recirculating hydroponic crop production systems. Methods for recovering nutrients from crop residues have evolved from water soaking (leaching) to rapid aerobic bioreactor processing. Leaching residues recovered the majority of elements but it also recovered significant amounts of soluble organics. The high organic content of leachates was detrimental to plant growth. Aerobic bioreactor processing reduced the organic content ten-fold, which reduced or eliminated phytotoxic effects. Wheat and potato production studies were successful using effluents from reactors having with 8- to 1-day retention times. Aerobic bioreactor effluents supplied at least half of the crops elemental mass needs in these studies. Descriptions of leachate and effluent mineral content, biomass productivity, microbial activity, and nutrient budgets for potato and wheat are presented.

  5. Biogas production from energy crops and crop residues

    Energy Technology Data Exchange (ETDEWEB)

    Lehtomaeki, A.

    2006-07-01

    The feasibility of utilising energy crops and crop residues in methane production through anaerobic digestion in boreal conditions was evaluated in this thesis. Potential boreal energy crops and crop residues were screened for their suitability for methane production, and the effects of harvest time and storage on the methane potential of crops was evaluated. Codigestion of energy crops and crop residues with cow manure, as well as digestion of energy crops alone in batch leach bed reactors with and without a second stage upflow anaerobic sludge blanket reactor (UASB) or methanogenic filter (MF) were evaluated. The methane potentials of crops, as determined in laboratory methane potential assays, varied from 0.17 to 0.49 m3 CH{sub 4} kg-1 VS{sub added} (volatile solids added) and from 25 to 260 m3 CH4 t-1 ww (tons of wet weight). Jerusalem artichoke, timothy-clover and reed canary grass gave the highest methane potentials of 2 900-5 400 m3 CH{sub 4} ha-1, corresponding to a gross energy potential of 28-53 MWh ha-1 and 40 000-60 000 km ha-1 in passenger car transport. The methane potentials per ww increased with most crops as the crops matured. Ensiling without additives resulted in minor losses (0-13%) in the methane potential of sugar beet tops but more substantial losses (17-39%) in the methane potential of grass, while ensiling with additives was shown to have potential in improving the methane potentials of these substrates by up to 19-22%. In semi-continuously fed laboratory continuously stirred tank reactors (CSTRs) co-digestion of manure and crops was shown feasible with feedstock VS containing up to 40% of crops. The highest specific methane yields of 0.268, 0.229 and 0.213 m3 CH{sub 4} kg-1 VS{sub added} in co-digestion of cow manure with grass, sugar beet tops and straw, respectively, were obtained with 30% of crop in the feedstock, corresponding to 85-105% of the methane potential in the substrates as determined by batch assays. Including 30% of crop in

  6. Ammonia volatilization from crop residues and frozen green manure crops

    NARCIS (Netherlands)

    Ruijter, de F.J.; Huijsmans, J.F.M.; Rutgers, B.

    2010-01-01

    Agricultural systems can lose substantial amounts of nitrogen (N). To protect the environment, the European Union (EU) has adopted several directives that set goals to limit N losses. National Emission Ceilings (NEC) are prescribed in the NEC directive for nitrogen oxides and ammonia. Crop residues

  7. Agricultural Residues and Biomass Energy Crops

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-06-01

    There are many opportunities to leverage agricultural resources on existing lands without interfering with production of food, feed, fiber, or forest products. In the recently developed advanced biomass feedstock commercialization vision, estimates of potentially available biomass supply from agriculture are built upon the U.S. Department of Agriculture’s (USDA’s) Long-Term Forecast, ensuring that existing product demands are met before biomass crops are planted. Dedicated biomass energy crops and agricultural crop residues are abundant, diverse, and widely distributed across the United States. These potential biomass supplies can play an important role in a national biofuels commercialization strategy.

  8. Ammonia volatilization from crop residues and frozen green manure crops

    Science.gov (United States)

    de Ruijter, F. J.; Huijsmans, J. F. M.; Rutgers, B.

    2010-09-01

    Agricultural systems can lose substantial amounts of nitrogen (N). To protect the environment, the European Union (EU) has adopted several directives that set goals to limit N losses. National Emission Ceilings (NEC) are prescribed in the NEC directive for nitrogen oxides and ammonia. Crop residues may contribute to ammonia volatilization, but sufficient information on their contribution to the national ammonia volatilization is lacking. Experiments were carried out with the aim to assess the ammonia volatilization of crop residues left on the soil surface or incorporated into the soil under the conditions met in practice in the Netherlands during late autumn and winter. Ammonia emission from residues of broccoli, leek, sugar beet, cut grass, fodder radish (fresh and frozen) and yellow mustard (frozen) was studied during two winter seasons using volatilization chambers. Residues were either placed on top of soil or mixed with soil. Mixing residues with soil gave insignificant ammonia volatilization, whereas volatilization was 5-16 percent of the N content of residues when placed on top of soil. Ammonia volatilization started after at least 4 days. Total ammonia volatilization was related to C/N-ratio and N concentration of the plant material. After 37 days, cumulative ammonia volatilization was negligible from plant material with N concentration below 2 percent, and was 10 percent of the N content of plant material with 4 percent N. These observations can be explained by decomposition of plant material by micro-organisms. After an initial built up of the microbial population, NH 4+ that is not needed for their own growth is released and can easily emit as NH 3 at the soil surface. The results of the experiments were used to estimate the contribution of crop residues to ammonia volatilization in the Netherlands. Crop residues of arable crops and residues of pasture topping may contribute more than 3 million kg NH 3-N to the national ammonia volatilization of the

  9. Fluorescence imaging to quantify crop residue cover

    Science.gov (United States)

    Daughtry, C. S. T.; Mcmurtrey, J. E., III; Chappelle, E. W.

    1994-01-01

    Crop residues, the portion of the crop left in the field after harvest, can be an important management factor in controlling soil erosion. Methods to quantify residue cover are needed that are rapid, accurate, and objective. Scenes with known amounts of crop residue were illuminated with long wave ultraviolet (UV) radiation and fluorescence images were recorded with an intensified video camera fitted with a 453 to 488 nm band pass filter. A light colored soil and a dark colored soil were used as background for the weathered soybean stems. Residue cover was determined by counting the proportion of the pixels in the image with fluorescence values greater than a threshold. Soil pixels had the lowest gray levels in the images. The values of the soybean residue pixels spanned nearly the full range of the 8-bit video data. Classification accuracies typically were within 3(absolute units) of measured cover values. Video imaging can provide an intuitive understanding of the fraction of the soil covered by residue.

  10. Hydroponic Crop Production using Recycled Nutrients from Inedible Crop Residues

    Science.gov (United States)

    Garland, Jay L.; Mackowiak, Cheryl L.; Sager, John C.

    1993-01-01

    The coupling of plant growth and waste recycling systems is an important step toward the development of bioregenerative life support systems. This research examined the effectiveness of two alternative methods for recycling nutrients from the inedible fraction (residue) of candidate crops in a bioregenerative system as follows: (1) extraction in water, or leaching, and (2) combustion at 550 C, with subsequent reconstitution of the ash in acid. The effectiveness of the different methods was evaluated by (1) comparing the percent recovery of nutrients, and (2) measuring short- and long-term plant growth in hydroponic solutions, based on recycled nutrients.

  11. Crop residue decomposition in Minnesota biochar amended plots

    OpenAIRE

    S. L. Weyers; K. A. Spokas

    2014-01-01

    Impacts of biochar application at laboratory scales are routinely studied, but impacts of biochar application on decomposition of crop residues at field scales have not been widely addressed. The priming or hindrance of crop residue decomposition could have a cascading impact on soil processes, particularly those influencing nutrient availability. Our objectives were to evaluate biochar effects on field decomposition of crop residue, using plots that were amended with ...

  12. Nitrogen Transfer from Cover Crop Residues to Onion Grown under Minimum Tillage in Southern Brazil

    Directory of Open Access Journals (Sweden)

    Leoncio de Paula Koucher

    2017-08-01

    Full Text Available ABSTRACT Nitrogen derived from cover crop residues may contribute to the nutrition of onion grown under minimum tillage (MT and cultivated in rotation. The aim of this study was to evaluate the N transferred from different cover crop residues to the onion crop cultivated under MT in southern Brazil. In June 2014, oilseed radish, black oat, and oilseed radish + black oat residues labeled with 15N were deposited on the soil surface before transplanting onions. During the growth season and at harvest, young expanded onion leaves, complete plants, and samples from different soil layers were collected and analyzed for recovery of 15N-labeled residue. Oilseed radish decomposed faster than other residues and 4 % of residue N was recovered in leaves and bulbs at harvest, but in general, N in plant organs was derived from sources other than the cover crop residues. In addition, leaf N was in the proper range for all treatments and was adequately mobilized to the bases for bulbing. The N derived from decomposing residues contributed little to onion development and the use of these plants should be chosen based on their advantages for physical and biological soil quality.

  13. The potential for energy production from crop residues in Zimbabwe

    Energy Technology Data Exchange (ETDEWEB)

    Jingura, R.M.; Matengaifa, R. [School of Engineering Sciences and Technology, Chinhoyi University of Technology, P. Bag 7724, Chinhoyi (Zimbabwe)

    2008-12-15

    There is increasing interest in Zimbabwe in the use of renewable energy sources as a means of meeting the country's energy requirements. Biomass provides 47% of the gross energy consumption in Zimbabwe. Energy can be derived from various forms of biomass using various available conversion technologies. Crop residues constitute a large part of the biomass available from the country's agriculture-based economy. The potential for energy production of crop residues is examined using data such as estimates of the quantities of the residues and their energy content. The major crops considered are maize, sugarcane, cotton, soyabeans, groundnuts, wheat, sorghum, fruits and forestry plantations. Quantities of residues are estimated from crop yields by using conversion coefficients for the various crops. Long-term crop yields data from 1970 to 1999 were used. Total annual residue yields for crops, fruits and forestry plantations are 7.805 Mt, 378 kt and 3.05 Mt, respectively. The crops, fruits and forestry residues have energy potential of 81.5, 4.9 and 44.3 PJ per year, respectively. This represents about 44% of the gross energy consumption in Zimbabwe. The need to balance use of crop residues for both energy purposes and other purposes such as animal feeding and soil fertility improvement is also highlighted. (author)

  14. Crop residues for advanced biofuels workshop: A synposis

    Science.gov (United States)

    Crop residues are being harvested for a variety of purposes including their use as livestock feed and to produce advanced biofuels. Crop residue harvesting, by definition, reduces the potential annual carbon input to the soil from aboveground biomass but does not affect input from plant roots. The m...

  15. Nitrous oxide emission from soils amended with crop residues

    NARCIS (Netherlands)

    Velthof, G.L.; Kuikman, P.J.; Oenema, O.

    2002-01-01

    Crop residues incorporated in soil are a potentially important source of nitrous oxide (N2O), though poorly quantified. Here, we report on the N2O emission from 10 crop residues added to a sandy and a clay soil, both with and without additional nitrate (NO3-). In the sandy soil, total nitrous oxide

  16. Studies on the effects of application of different foliar fertilizer materials, crop residue and inter cropping on Banana plants

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, Yusuf Munim [Faculty of Agriculture, University of Khartoum, Khartoum (Sudan)

    1997-12-31

    Five separate experiments were conducted at university of Khartoum demonstration farm during 1993 to 1995 under both orchard and nursery conditions to evaluate the effect of foliar application of different fertilizers, use of crop residue and intercropping on banana (dwarf cavendish). In the first experiment, the effects of foliar application of different concentrations of potassium solution (38%) were studied. The results indicated that application of all concentrations resulted in greater increases in overall growth parameters, higher leaf-N, P, K, Ca, Mg, Mn, Fe, Zn and Cu contents, higher values of yield and yield components , finger length of both plant crop and the first ratoon crop and reduction of time from planting to flowering and from flowering to harvesting of both plant crop and the first crop compared to the control. In the second experiment, the effects of three different foliar fertilizers, namely, compound cryst, fetrilon comb-2 and x-garden were investigated. The results revealed that all fertilizers gave greater values of all growth parameters, higher leaf-N, P, K, Ca, Mg, Mn, Fe, Zn and Cu contents, higher values of yield and yield components , finger length of both plant crop and the first ratoon crop and reduction of time from planting to flowering and from flowering to harvesting of both plant crop and the first crop compared to the control. In the third experiment, the effect of four different fertilizer materials containing different combinations of NPK on growth parameters and nutrient elements contents of leaves of banana suckers grown under nursery conditions was evaluated. The results revealed that all fertilizer materials gave greater increases of growth parameters over the control as well as higher leaf-N, P, K, Ca, Mg, Mn, Fe, Zn and Cu contents. In the fourth experiment, the effect of different concentrations of N{sub 19}, P{sub 19}, K{sub 19} fertilizers on growth characteristics and nutrient elements contents of leaves of banana

  17. Studies on the effects of application of different foliar fertilizer materials, crop residue and inter cropping on Banana plants

    International Nuclear Information System (INIS)

    Hassan, Yusuf Munim

    1996-01-01

    Five separate experiments were conducted at university of Khartoum demonstration farm during 1993 to 1995 under both orchard and nursery conditions to evaluate the effect of foliar application of different fertilizers, use of crop residue and intercropping on banana (dwarf cavendish). In the first experiment, the effects of foliar application of different concentrations of potassium solution (38%) were studied. The results indicated that application of all concentrations resulted in greater increases in overall growth parameters, higher leaf-N, P, K, Ca, Mg, Mn, Fe, Zn and Cu contents, higher values of yield and yield components , finger length of both plant crop and the first ratoon crop and reduction of time from planting to flowering and from flowering to harvesting of both plant crop and the first crop compared to the control. In the second experiment, the effects of three different foliar fertilizers, namely, compound cryst, fetrilon comb-2 and x-garden were investigated. The results revealed that all fertilizers gave greater values of all growth parameters, higher leaf-N, P, K, Ca, Mg, Mn, Fe, Zn and Cu contents, higher values of yield and yield components , finger length of both plant crop and the first ratoon crop and reduction of time from planting to flowering and from flowering to harvesting of both plant crop and the first crop compared to the control. In the third experiment, the effect of four different fertilizer materials containing different combinations of NPK on growth parameters and nutrient elements contents of leaves of banana suckers grown under nursery conditions was evaluated. The results revealed that all fertilizer materials gave greater increases of growth parameters over the control as well as higher leaf-N, P, K, Ca, Mg, Mn, Fe, Zn and Cu contents. In the fourth experiment, the effect of different concentrations of N 19 , P 19 , K 19 fertilizers on growth characteristics and nutrient elements contents of leaves of banana suckers was

  18. Cycling of fertilizer and cotton crop residue nitrogen

    International Nuclear Information System (INIS)

    Rochester, I.J.; Constable, G.A.; MacLeod, D.A.

    1993-01-01

    Mineral nitrogen (N), nitrate and ammonium contents were monitored in N-fertilized soils supporting cotton crops to provide information on the nitrification, mineralization and immobilization processes operating in the soil. The relative contributions of fertilizer N, previous cotton crop residue N and indigenous soil N to the mineral N pools and to the current crop's N uptake were calculated. After N fertilizer (urea) application, the soil's mineral N content rose rapidly and subsequently declined at a slower rate. The recovery of 15 N-labelled urea as mineral N declined exponentially with time. Biological immobilization (and possibly denitrification to some extent) were believed to be the major processes reducing post-application soil mineral N content. Progressively less N was mineralized upon incubation of soil sampled through the growing season. Little soil N (either from urea or crop residue) was mineralized at crop maturity. Cycling of N was evident between the soil mineral and organic N pools throughout the cotton growing season. Considerable quantities of fertilizer N were immobilized by the soil micro biomass; immobilized N was remineralized and subsequently taken up by the cotton crop. A large proportion of the crop N was taken up in the latter part of the season when the soil mineral N content was low. It is suggested that much of the N taken up by cotton was derived from microbial sources, rather than crop residues. The application of cotton crop residue (stubble) slightly reduced the mineral N content in the soil by encouraging biological immobilization. 15 N was mineralized very slowly from the labelled crop residue and did not contribute significantly to the supply of N to the current crop. Recovery of labelled fertilizer N and labelled crop residue N by the cotton crop was 28% and 1%, respectively. In comparison, the apparent recovery of fertilizer N was 48%. Indigenous soil N contributed 68% of the N taken up by the cotton crop. 33 refs., 1 tab

  19. Impact of Corn Residue Removal on Crop and Soil Productivity

    Science.gov (United States)

    Johnson, J. M.; Wilhelm, W. W.; Hatfield, J. L.; Voorhees, W. B.; Linden, D.

    2003-12-01

    Over-reliance on imported fuels, increasing atmospheric levels of greenhouses and sustaining food production for a growing population are three of the most important problems facing society in the mid-term. The US Department of Energy and private enterprise are developing technology necessary to use high cellulose feedstock, such as crop residues, for ethanol production. Based on production levels, corn (Zea mays L.) residue has potential as a biofuel feedstock. Crop residues are a renewable and domestic fuel source, which can reduce the rate of fossil fuel use (both imported and domestic) and provide an additional farm commodity. Crop residues protect the soil from wind and water erosion, provide inputs to form soil organic matter (a critical component determining soil quality) and play a role in nutrient cycling. Crop residues impact radiation balance and energy fluxes and reduce evaporation. Therefore, the benefits of using crop residues as fuel, which removes crop residues from the field, must be balanced against negative environmental impacts (e.g. soil erosion), maintaining soil organic matter levels, and preserving or enhancing productivity. All ramifications of new management practices and crop uses must be explored and evaluated fully before an industry is established. There are limited numbers of long-term studies with soil and crop responses to residue removal that range from negative to negligible. The range of crop and soil responses to crop residue removal was attributed to interactions with climate, management and soil type. Within limits, corn residue can be harvested for ethanol production to provide a renewable, domestic source of energy feedstock that reduces greenhouse gases. Removal rates must vary based on regional yield, climatic conditions and cultural practices. Agronomists are challenged to develop a protocol (tool) for recommending maximum permissible removal rates that ensure sustained soil productivity.

  20. Cover crop residue effects on machine-induced soil compaction

    OpenAIRE

    Ess, Daniel R.

    1994-01-01

    Crop production systems which utilize the biomass produced by rye (Secale cereale ) to suppress weed growth and conserve soil moisture have been developed at Virginia Tech. The success of alternative, reduced-input crop production systems has encouraged research into the potential for breaking the traffic-tillage cycle associated with conventional tillage crop production systems. The fragile residues encountered in agricultural crop production, whether incorporated into the ...

  1. Biogas Production from Energy Crops and Agriculture Residues

    DEFF Research Database (Denmark)

    Wang, Guangtao

    and wet explosion pretreated energy crops and agriculture residues with swine manure at various volatile solids (VS) ratio between crop and manure was carried out by batch tests and continuous experiments. The efficiency of the co-digestion experiment was evaluated based on (a) the methane potential......In this thesis, the feasibility of utilizing energy crops (willow and miscanthus) and agriculture residues (wheat straw and corn stalker) in an anaerobic digestion process for biogas production was evaluated. Potential energy crops and agriculture residues were screened according...... of perennial crops was tested as a storage method and pretreatment method for enhancement of the biodegradability of the crops. The efficiency of the silage process was evaluated based on (a) the amount of biomass loss during storage and (b) the effect of the silage on methane potential. Co-digestion of raw...

  2. Cover crop residue management for optimizing weed control

    NARCIS (Netherlands)

    Kruidhof, H.M.; Bastiaans, L.; Kropff, M.J.

    2009-01-01

    Although residue management seems a key factor in residue-mediated weed suppression, very few studies have systematically compared the influence of different residue management strategies on the establishment of crop and weed species. We evaluated the effect of several methods of pre-treatment and

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

    International Nuclear Information System (INIS)

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

    2011-01-01

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

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

    Science.gov (United States)

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

    2015-04-01

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

  5. Evaluation of Crops Sensitivity to Atrazine Soil Residual

    Directory of Open Access Journals (Sweden)

    E Izadi

    2012-02-01

    Full Text Available Abstract In order to study the sensitivity of 9 crops to atrazine soil residual, two separate experiments were conducted in field and greenhouse conditions. First experiment was conducted in a field with treated soil by atrazine based on split plot and the results evaluated in greenhouse conditions. Treatments in the field experiment included two organic manure application rates (0 and 50 t/ha as main plots and 2 atrazine application rates (2 and 4 kg/ha atrazine a.i. as sob plots. After corn harvesting soil was sampled at 0-15 cm surface layer in each plots in 15 points, after mixing the samples. Wheat, barley, sugar beet, pea, lens and colza planted in pots at greenhouse. Second experiment conducted in greenhouse conditions for evaluation of atrazine soil residual in completely randomized design. Treatments included atrazine soil residual concentrations (0, 0.2, 0.5, 1, 5, 10 and 15 mg/kg soil and crops included wheat, barley, sugar beet, pea, lens, rape, bean and tomato. Results showed that atrazine residue had no effect on crops growth in field experiment treated with atrazine. It seems that atrazine residue in filed soil is lower that its damage threshold for crops or maybe for its fast removal in field than in control conditions. But in bioassay experiment (greenhouse experiment crops response to atrazine residues were different. Results showed that onion and pea were most susceptible ant tolerant crops between studied species and based of ED50 parameter the other crops tolerance to total residue ranked as: pea< bean< lentil< sugar beet< tomato< barley< wheat< rape< onion. Keywords: Atrazine residue, Pea, Bean, Lentil, Sugar beet, Barley, Wheat, Rape, Tomato

  6. Biogas production from energy crops and agriculture residues

    Energy Technology Data Exchange (ETDEWEB)

    Wang, G.

    2010-12-15

    In this thesis, the feasibility of utilizing energy crops (willow and miscanthus) and agriculture residues (wheat straw and corn stalker) in an anaerobic digestion process for biogas production was evaluated. Potential energy crops and agriculture residues were screened according to their suitability for biogas production. Moreover, pretreatment of these biomasses by using wet explosion method was studied and the effect of the wet explosion process was evaluated based on the increase of (a) sugar release and (b) methane potential when comparing the pretreated biomass and raw biomass. Ensiling of perennial crops was tested as a storage method and pretreatment method for enhancement of the biodegradability of the crops. The efficiency of the silage process was evaluated based on (a) the amount of biomass loss during storage and (b) the effect of the silage on methane potential. Co-digestion of raw and wet explosion pretreated energy crops and agriculture residues with swine manure at various volatile solids (VS) ratio between crop and manure was carried out by batch tests and continuous experiments. The efficiency of the co-digestion experiment was evaluated based on (a) the methane potential in term of ml CH4 produced per g of VS-added and (b) the amount of methane produced per m3 of reactor volume. (Author)

  7. Crop residue decomposition in Minnesota biochar-amended plots

    Science.gov (United States)

    Weyers, S. L.; Spokas, K. A.

    2014-06-01

    Impacts of biochar application at laboratory scales are routinely studied, but impacts of biochar application on decomposition of crop residues at field scales have not been widely addressed. The priming or hindrance of crop residue decomposition could have a cascading impact on soil processes, particularly those influencing nutrient availability. Our objectives were to evaluate biochar effects on field decomposition of crop residue, using plots that were amended with biochars made from different plant-based feedstocks and pyrolysis platforms in the fall of 2008. Litterbags containing wheat straw material were buried in July of 2011 below the soil surface in a continuous-corn cropped field in plots that had received one of seven different biochar amendments or a uncharred wood-pellet amendment 2.5 yr prior to start of this study. Litterbags were collected over the course of 14 weeks. Microbial biomass was assessed in treatment plots the previous fall. Though first-order decomposition rate constants were positively correlated to microbial biomass, neither parameter was statistically affected by biochar or wood-pellet treatments. The findings indicated only a residual of potentially positive and negative initial impacts of biochars on residue decomposition, which fit in line with established feedstock and pyrolysis influences. Overall, these findings indicate that no significant alteration in the microbial dynamics of the soil decomposer communities occurred as a consequence of the application of plant-based biochars evaluated here.

  8. Crop residue decomposition in Minnesota biochar amended plots

    Science.gov (United States)

    Weyers, S. L.; Spokas, K. A.

    2014-02-01

    Impacts of biochar application at laboratory scales are routinely studied, but impacts of biochar application on decomposition of crop residues at field scales have not been widely addressed. The priming or hindrance of crop residue decomposition could have a cascading impact on soil processes, particularly those influencing nutrient availability. Our objectives were to evaluate biochar effects on field decomposition of crop residue, using plots that were amended with biochars made from different feedstocks and pyrolysis platforms prior to the start of this study. Litterbags containing wheat straw material were buried below the soil surface in a continuous-corn cropped field in plots that had received one of seven different biochar amendments or a non-charred wood pellet amendment 2.5 yr prior to start of this study. Litterbags were collected over the course of 14 weeks. Microbial biomass was assessed in treatment plots the previous fall. Though first-order decomposition rate constants were positively correlated to microbial biomass, neither parameter was statistically affected by biochar or wood-pellet treatments. The findings indicated only a residual of potentially positive and negative initial impacts of biochars on residue decomposition, which fit in line with established feedstock and pyrolysis influences. Though no significant impacts were observed with field-weathered biochars, effective soil management may yet have to account for repeat applications of biochar.

  9. Crop residue decomposition, residual soil organic matter and nitrogen mineralization in arable soils with contrasting textures

    NARCIS (Netherlands)

    Matus, F.J.

    1994-01-01

    To evaluate the significance of cropping, soil texture and soil structure for the decomposition of 14C- and 15N-labelled crop residues, a study was conducted in a sand and a

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

    International Nuclear Information System (INIS)

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

    2010-01-01

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

  11. Biological treatment of crop residues for ruminant feeding: A review

    African Journals Online (AJOL)

    Dell

    2013-07-03

    Jul 3, 2013 ... Further, recent studies have indicated low methane emission from feedstuffs subjected to solid state fermentation (SSF) with ... many tropical countries subsist mainly on crop residue based diets. The increasing ... partial breakdown of the lignin-carbohydrate complex. (Keller et al., 2003) thus improving their ...

  12. Quantification and characterization of cotton crop biomass residue

    Science.gov (United States)

    Cotton crop residual biomass remaining in the field after mechanical seed cotton harvest is not typically harvested and utilized off-site thereby generating additional revenue for producers. Recently, interest has increased in utilizing biomass materials as feedstock for the production of fuel and ...

  13. The allelopathic effects of three crop residues on the germination ...

    African Journals Online (AJOL)

    ... maize inflorescences showed significant differences when compared to the control. No growth was recorded in the radicle until 96 hrs of the experiment in all the extract – treated seeds from the three crop residues while the control germinated at 72 hours. Keywords: Allelopathy, allelochemical, biomolecules, Sphenostylis ...

  14. Feeding potential of summer grain crop residues for woolled sheep ...

    African Journals Online (AJOL)

    of 80:20 for the first collection on maize residues. Schoonraad (1985) did not pick up the cobs, so much more grain was available. Crude protein content. Changes in percentage crude protein in oesophageal samples are shown in Figure 2. With all crops, CP content of oesophageal samples was initially high but decreased ...

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

    Directory of Open Access Journals (Sweden)

    Hiel, MP.

    2016-01-01

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

  16. Relative availability of crop residue-N in rice cultivation

    International Nuclear Information System (INIS)

    Sirwando, H; Abdullah, N.

    1988-01-01

    The use of plant residues for soil amendment will reduce the use of chemical fertilizers. The experiment to study the uptake of N from various plant residues by rice crop. Three kinds of plant residue of soybean labelled with 15-N. Four levels of urea (0, 15, 30, 40 kg N/ha) were applied to aluvial soil from Pusakanegara. The factorial experiment was conducted in fully randomize design, with plant residues as the main treatment, and rate of urea as substreatment. The results obtained from this experiment showed that plant dry weight, N content of grain, straw, and the whole plant of Atomita I rice treated with soybean strow seens to be higher than those treated with the straw of rice or corn. (author). 6 refs.; 7 tabs

  17. Postharvest residues from grass seed crops for bioenergy

    OpenAIRE

    Simić, Aleksandar; Čolić, Vladislava; Vučković, Savo; Dželetović, Željko; Bijelić, Zorica; Mandić, Violeta

    2016-01-01

    During grass seed production, a large amount of low forage quality biomass has been produced. Tall growing perennial grasses such as tall fescue (Festuca arundinacea L.) and Italian ryegrass (Lolium multiflorum Lam.) can be used as an alternative source for bioenergy production as they can be grown in less cultivated areas, their residues in seed production could be valuable energy source and can be potentially used as a dual purpose crop (bioenergy and forage). In this research, potentials o...

  18. Screening boreal energy crops and crop residues for methane biofuel production

    Energy Technology Data Exchange (ETDEWEB)

    Lehtomaeki, A.; Rintala, J.A. [Department of Biological and Environmental Science, University of Jyvaeskylae, P.O. Box 35, FI-40014 Jyvaeskylae (Finland); Viinikainen, T.A. [Department of Chemistry, University of Jyvaeskylae, P.O. Box 35, FI-40014 Jyvaeskylae (Finland)

    2008-06-15

    The purpose of the study was to screen potential boreal energy crops and crop residues for their suitability in methane production and to investigate the effect of harvest time on the methane production potential of different crops. The specific methane yields of crops, determined in 100-200 d methane potential assays, varied from 0.17 to 0.49 m{sup 3} CH{sub 4} kg{sup -1} VS{sub added} (volatile solids added) and from 25 to 260 m{sup 3} CH{sub 4} t{sub ww}{sup -1} (tonnes of wet weight). Jerusalem artichoke, timothy-clover grass and reed canary grass gave the highest potential methane yields of 2900-5400 m{sup 3} CH{sub 4} ha{sup -1}, corresponding to a gross energy yield of 28-53 MWh ha{sup -1} and ca. 40,000-60,000 km ha{sup -1} in passenger car transport. The effect of harvest time on specific methane yields per VS of crops varied a lot, whereas the specific methane yields per t{sub ww} increased with most crops as the crops matured. (author)

  19. Decomposition of sugar cane crop residues under different nitrogen rates

    Directory of Open Access Journals (Sweden)

    Douglas Costa Potrich

    2014-09-01

    Full Text Available The deposition of organic residues through mechanical harvesting of cane sugar is a growing practice in sugarcane production system. The maintenance of these residues on the soil surface depends mainly on environmental conditions. Nitrogen fertilization on dry residues tend to retard decomposition of these, providing benefits such as increased SOM. Thus, the object of this research was to evaluate the effect of different doses of nitrogen on sugar cane crop residues, as its decomposition and contribution to carbon sequestration in soil. The experiment was conducted in Dourados-MS and consisted of a randomized complete block design. Dried residues were placed in litter bags and the treatments were arranged in a split plot, being the four nitrogen rates (0, 50, 100 and 150 kg ha-1 N the plots, and the seven sampling times (0, 30, 60, 90, 120, 150 and 180 the spit plots. Decomposition rates of residues, total organic carbon and labile carbon on soil were analysed. The application of increasing N doses resulted in an increase in their decomposition rates. Despite this, note also the mineral N application as a strategy to get higher levels of labile carbon in soil.

  20. Multi-Seasonal Nitrogen Recoveries from Crop Residue in Soil and Crop in a Temperate Agro-Ecosystem.

    Directory of Open Access Journals (Sweden)

    Guoqing Hu

    Full Text Available In conservation tillage systems, at least 30% of the soil surface was covered by crop residues which generally contain significant amounts of nitrogen (N. However, little is known about the multi-seasonal recoveries of the N derived from these crop residues in soil-crop systems, notably in northeastern China. In a temperate agro-ecosystem, 15N-labeled maize residue was applied to field surfaces in the 1st year (2009. From the 2nd to 4th year (2010-2012, one treatment halted the application of maize residue, whereas the soil in the second treatment was re-applied with unlabeled maize residue. Crop and soil samples were collected after each harvest, and their 15N enrichments were determined on an isotope ratio mass spectrometer to trace the allocation of N derived from the initially applied maize residue in the soil-crop systems. On average, 8.4% of the maize residue N was recovered in the soil-crop in the 1st year, and the vast majority (61.9%-91.9% was recovered during subsequent years. Throughout the experiment, the cumulative recovery of the residue N in the crop increased gradually (18.2%-20.9%, but most of the residue N was retained in the soil, notably in the 0-10 cm soil layer. Compared to the single application, the sequential residue application significantly increased the recovery of the residue N in the soil profile (73.8% vs. 40.9% and remarkably decreased the total and the initially applied residue derived mineral N along the soil profile. Our results suggested that the residue N was actively involved in N cycling, and its release and recovery in crop and soil profile were controlled by the decomposition process. Sequential residue application significantly enhanced the retention and stabilization of the initially applied residue N in the soil and retarded its translocation along the soil profile.

  1. Multi-Seasonal Nitrogen Recoveries from Crop Residue in Soil and Crop in a Temperate Agro-Ecosystem.

    Science.gov (United States)

    Hu, Guoqing; Liu, Xiao; He, Hongbo; Zhang, Wei; Xie, Hongtu; Wu, Yeye; Cui, Jiehua; Sun, Ci; Zhang, Xudong

    2015-01-01

    In conservation tillage systems, at least 30% of the soil surface was covered by crop residues which generally contain significant amounts of nitrogen (N). However, little is known about the multi-seasonal recoveries of the N derived from these crop residues in soil-crop systems, notably in northeastern China. In a temperate agro-ecosystem, 15N-labeled maize residue was applied to field surfaces in the 1st year (2009). From the 2nd to 4th year (2010-2012), one treatment halted the application of maize residue, whereas the soil in the second treatment was re-applied with unlabeled maize residue. Crop and soil samples were collected after each harvest, and their 15N enrichments were determined on an isotope ratio mass spectrometer to trace the allocation of N derived from the initially applied maize residue in the soil-crop systems. On average, 8.4% of the maize residue N was recovered in the soil-crop in the 1st year, and the vast majority (61.9%-91.9%) was recovered during subsequent years. Throughout the experiment, the cumulative recovery of the residue N in the crop increased gradually (18.2%-20.9%), but most of the residue N was retained in the soil, notably in the 0-10 cm soil layer. Compared to the single application, the sequential residue application significantly increased the recovery of the residue N in the soil profile (73.8% vs. 40.9%) and remarkably decreased the total and the initially applied residue derived mineral N along the soil profile. Our results suggested that the residue N was actively involved in N cycling, and its release and recovery in crop and soil profile were controlled by the decomposition process. Sequential residue application significantly enhanced the retention and stabilization of the initially applied residue N in the soil and retarded its translocation along the soil profile.

  2. Amendment of Acid Soils with Crop Residues and Biochars

    Institute of Scientific and Technical Information of China (English)

    YUAN Jin-Hua; XU Ren-Kou; WANG Ning; LI Jiu-Yu

    2011-01-01

    The liming potential of some crop residues and their biochars on an acid Ultisol was investigated using incubation experiments. Rice hulls showed greater liming potential than rice hull biochar, while soybean and pea straws had less liming potential than their biochars. Due to their higher alkalinity, biochars from legume materials increased soil pH much compared to biochars from non-legume materials. The alkalinity of biochars was a key factor affecting their liming potential,and the greater alkalinity of biochars led to greater reductions in soil acidity. The incorporation of biochars decreased soil exchangeable acidity and increased soil exchangeable base cations and base saturation, thus improving soil fertility.

  3. Survival of pathogens of Brussels sprouts (Brassica oleracea Gemifera group) in crop residues

    NARCIS (Netherlands)

    Köhl, J.; Vlaswinkel, M.E.T.; Groenenboom-de Haas, B.H.; Kastelein, P.; Hoof, van R.A.; Wolf, van der J.M.; Krijger, M.C.

    2011-01-01

    Mycosphaerella brassicicola (ringspot), Alternaria brassicicola and A. brassicae (dark leaf spot) and Xanthomonas campestris pv. campestris (black spot) can infect leaves of Brussels sprouts resulting in yield losses. Infections of outer leaves of sprouts cause severe losses in quality. Crop

  4. Responses of Pea (Pisum sativum Growth and Yield to Residual Effects of Organic and Urea Fertilizers from Previous Crop

    Directory of Open Access Journals (Sweden)

    S. Fallah

    2016-07-01

    Full Text Available Application of organic manure in organic farming and long-term mineralization may lead to residual effects on the succeeding crop. So, residual effects of combined cattle manure and urea fertilizer of previous crop (black cumin on growth and yield of pea were examined in a randomized complete block design. Treatments included of  cattle manure (CM, urea (U, three ratios of CM+U full dose application (2:1; 1:1; 1:2 and three ratios of CM+U split application (2:1; 1:1; 1:2, and unfertilized control to previous crop (black cumin in 2012. Pea planted without any fertilizer in 2013. There was no significant difference between control and residual of urea treatment for some parameters including dry matter in flowering stage, plant nitrogen and phosphorus concentration, plant height, yield components, grain yield and biological yield of pea. Biological and grain yields were greater under both residual of cattle manure treatment and integrated treatments compared to residual of urea treatment. The highest grain yield (4000 kg ha-1 was observed in residual of CM:U full dosed application treatment, to the extent that grain yield in this treatment indicated a 1.5-fold increase in comparison with residual of urea treatment. The highest biological yield (8325 kg ha-1 was obtained in residual of CM treatment, though it was not significant different from that of residual of CM:U (1:2 treatments. In general, although residual of urea fertilizer did not leave a notable effect on pea production, but production of this crop relying on residual of cattle manure deems effective to lowering of fertilization cost and ameliorating environmental contaminations.

  5. Diversity in crop residue management across an intensification gradient in southern Africa

    NARCIS (Netherlands)

    Rusinamhodzi, Leonard; Corbeels, Marc; Giller, Ken E.

    2016-01-01

    Crop residues are important for livestock feed and nutrient cycling among many other functions on smallholder farming systems of sub-Saharan Africa. The objective of this study was to assess differences in resource endowment, crop productivity and crop residue management in selected sites in

  6. Characterization of Proteins in Filtrate from Biodegradation of Crop Residue

    Science.gov (United States)

    Horton, Wileatha; Trotman, A. A.

    1997-01-01

    Biodegradation of plant biomass is a feasible path for transformation of crop residue and recycling of nutrients for crop growth. The need to model the effects of factors associated with recycling of plant biomass resulting from hydroponic sweet potato production has led to investigation of natural soil isolates with the capacity for starch hydrolysis. This study sought to use nondenaturing gel electrophoresis to characterize the proteins present in filtered effluent from bioreactors seeded with starch hydrolyzing bacterial culture used in the biodegradation of senesced sweet potato biomass. The study determined the relative molecular weight of proteins in sampled effluent and the protein banding pattern was characterized. The protein profiles of effluent were similar for samples taken from independent runs under similar conditions of starch hydrolysis. The method can be used as a quality control tool for confirmation of starch hydrolysis of crop biomass. In addition, this method will allow monitoring for presence of contaminants within the system-protein profiles indicative of new enzymes in the bioreactors.

  7. Mineralization of nitrogen from nitrogen-15 labeled crop residues and utilization by rice

    International Nuclear Information System (INIS)

    Norman, R.J.; Gilmour, J.T.; Wells, B.R.

    1990-01-01

    The availability of N from the residues of the previous crop to the subsequent rice (Oryza sativa L.) crop is largely unknown. The objectives of this study were to (1) measure the mineralization of N from 15 N-labeled rice, soybean (Glycine max L.), and wheat (Triticum aestivum L.) residues and the uptake by a subsequent rice crop; and (2) compare the 15 N tracer method with the standard fertilizer-N response method used in field studies to quantify the N contribution from the crop residue to the next crop. Nitrogen mineralization from decomposing crop residues was measured by soil sampling prior to seeding the rice crop and after seeding by plant sampling the rice at maturity. The minimum estimate of the amount of residue N mineralized from the time of residue incorporation until rice harvest was 9, 52, and 38% of the rice, soybean, and wheat residue N, respectively. The amount of residue N recovered in the rice crop was 3, 11, and 37% of the rice, soybean, and wheat residue N, respectively. The lower the C/N ratio and the higher the amount of N in the residue, the lower was the amount of residue N recovered in the soil organic fraction at harvest and the higher was the amount of residue N mineralized. The 15 N tracer method compared favorably with the fertilizer N response method when the uptake efficiency of the fertilizer N was taken into account

  8. Lignin biochemistry and soil N determine crop residue decomposition and soil priming

    Science.gov (United States)

    Cropping history can affect soil properties, including available N, but little is known about the interactive effects of residue biochemistry, temperature and cropping history on residue decomposition. A laboratory incubation examined the role of residue biochemistry and temperature on the decomposi...

  9. Nitrogen acquisition by pea and barley and the effect of their crop residues on available nitrogen for subsequent crops

    DEFF Research Database (Denmark)

    Jensen, E.S.

    1996-01-01

    Nitrogen acquisition by field pea (Pisum sativum L.) and spring barley (Hordeum vulgare L.) grown on a sandy loam soil and availability of N in three subsequent sequences of a cropping system were studied in an outdoor pot experiment. The effect of crop residues on the N availability was evaluated....... The dry matter production and total N uptake of a spring barley crop following pea or barley, with a period of unplanted soil in the autumn/winter, were significantly higher after pea than after barley. The barley crop following pea and barley recovered 11% of the pea and 8% of the barley residue N...

  10. Behavior of pyrimethanil, pyraclostrobin, boscalid, cypermethrin and chlorpyrifos residues on raspberry fruit and leaves of Laszka variety.

    Science.gov (United States)

    Sadło, Stanisław; Szpyrka, Ewa; Stawarczyk, Michał; Piechowicz, Bartosz

    2014-01-01

    The purpose of the research conducted was to investigate and evaluate the behavior of pyrimethanil, pyraclostrobin, boscalid, cypermethrin and chlorpyrifos, the active ingredients of selected fungicides and insecticides, on ripe fruit and in fully developed leaves of raspberry of the Laszka variety. The field trial was carried out in the period of one month starting from the first fruit picking. The results obtained indicated that residue levels on the day of the first crop picking did not even approximate the corresponding EU-MRLs (http://ec.europa.eu/sanco_pesticides). Individual substances in raspberry fruits and leaves disappeared at a similar rate. As a result of chlorpyrifos application to the soil, its residue in fruits and leaves occurred for the whole period of fruit bearing, though in fruit they dropped successively. To produce raspberries with residues below or equal to 0.01 μg g(-1), the application of pesticides should be stopped at least 2-3 weeks before the first crop picking, and on condition that an appropriate preparation (active in low doses) is applied to the last treatments.

  11. Increased occurrence of pesticide residues on crops grown in protected environments compared to crops grown in open field conditions.

    Science.gov (United States)

    Allen, Gina; Halsall, Crispin J; Ukpebor, Justina; Paul, Nigel D; Ridall, Gareth; Wargent, Jason J

    2015-01-01

    Crops grown under plastic-clad structures or in greenhouses may be prone to an increased frequency of pesticide residue detections and higher concentrations of pesticides relative to equivalent crops grown in the open field. To test this we examined pesticide data for crops selected from the quarterly reports (2004-2009) of the UK's Pesticide Residue Committee. Five comparison crop pairs were identified whereby one crop of each pair was assumed to have been grown primarily under some form of physical protection ('protected') and the other grown primarily in open field conditions ('open'). For each pair, the number of detectable pesticide residues and the proportion of crop samples containing pesticides were statistically compared (n=100 s samples for each crop). The mean concentrations of selected photolabile pesticides were also compared. For the crop pairings of cabbage ('open') vs. lettuce ('protected') and 'berries' ('open') vs. strawberries ('protected') there was a significantly higher number of pesticides and proportion of samples with multiple residues for the protected crops. Statistically higher concentrations of pesticides, including cypermethrin, cyprodinil, fenhexamid, boscalid and iprodione were also found in the protected crops compared to the open crops. The evidence here demonstrates that, in general, the protected crops possess a higher number of detectable pesticides compared to analogous crops grown in the open. This may be due to different pesticide-use regimes, but also due to slower rates of pesticide removal in protected systems. The findings of this study raise implications for pesticide management in protected-crop systems. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Cost Methodology for Biomass Feedstocks: Herbaceous Crops and Agricultural Residues

    Energy Technology Data Exchange (ETDEWEB)

    Turhollow Jr, Anthony F [ORNL; Webb, Erin [ORNL; Sokhansanj, Shahabaddine [ORNL

    2009-12-01

    This report describes a set of procedures and assumptions used to estimate production and logistics costs of bioenergy feedstocks from herbaceous crops and agricultural residues. The engineering-economic analysis discussed here is based on methodologies developed by the American Society of Agricultural and Biological Engineers (ASABE) and the American Agricultural Economics Association (AAEA). An engineering-economic analysis approach was chosen due to lack of historical cost data for bioenergy feedstocks. Instead, costs are calculated using assumptions for equipment performance, input prices, and yield data derived from equipment manufacturers, research literature, and/or standards. Cost estimates account for fixed and variable costs. Several examples of this costing methodology used to estimate feedstock logistics costs are included at the end of this report.

  13. Management of crop residues for sustainable crop production. Results of a co-ordinated research project 1996-2001

    International Nuclear Information System (INIS)

    2003-05-01

    Since ancient times, farmers have recognized the importance of organic matter inputs to enhance crop yields. Organic matter contributes to plant growth through beneficial effects on the physical, chemical, and biological properties of the soil, including (i) provision of a carbon and energy source for soil microbes, (ii) improvement of soil aggregation, thus reducing the hazard of erosion, (iii) retaining of nutrients and water, (iv) provision of nutrients through decomposition, and (v) reduction of soil compaction. The amount of soil organic matter is controlled by the balance between additions of plant and animal materials and losses by decomposition. Both additions and losses are directly affected by management practices. This CRP supported national efforts in eleven Member States to identify options managing crop residues for sustainable agricultural production and environmental preservation in a wide range of soils and cropping systems. Various options for the recycling of crop residues that are sustainable and economically attractive to farmers were examined using isotopic techniques. The specific options of this CRP were: to increase the quantity of nutrients available to crops from organic sources and for more effective recycling of those nutrients; to enhance the efficiency of use of nutrients by crops, and minimize losses through improved synchrony between process-level understanding of carbon and nutrient flow through the use of isotopic techniques so that management recommendations can be extrapolated to a wide range of environments using models. A simple mathematical model, descriptive in nature, was developed to synthesize information collected from all experimental sites, allowing comparisons between treatments and sites. Most of the fertilizer N was lost during the first cropping season and only insignificant losses occurred in the following seasons. The losses of N from applied fertilizer ranged from 45 to 85% irrespective of crop-residue

  14. Crop residue recycling for economic and environmental sustainability: The case of India

    Directory of Open Access Journals (Sweden)

    Devi Saroj

    2017-09-01

    Full Text Available India is one of the key producers of food grain, oilseed, sugarcane and other agricultural products. Agricultural crops generate considerable amounts of leftover residues, with increases in food production crop residues also increasing. These leftover residues exhibit not only resource loss but also a missed opportunity to improve a farmer’s income. The use of crop residues in various fields are being explored by researchers across the world in areas such as textile composite non-woven making processes, power generation, biogas production, animal feed, compost and manures, etc. The increasing trend in addition of bio-energy cogeneration plants, increasing demand for animal feedstock and increasing trend for organic agriculture indicates a competitive opportunity forcrop residue in Agriculture. It is to be noted that the use of this left over residue isoften not mutually exclusive which makes measurement of its economic value more difficult.For example, straw can be used as animal bedding and thereafter as a crop fertilizer. In view of this, the main aim of this paper envisaged to know about how much crop residue is left unutilized and how best they can be utilized for alternative purposes for environmental stewardship and sustainability. In this context, an attempt has been made to estimate the total crop residue across the states and its economic value though data available from various government sources and a SWOT analysis performed for possible alternative uses of residue in India. This paper also discusses the successful case studies of India and global level of use of crop residues in economic activities. Over all 516 Mtonnes of crop residue was produced in 2014-15 in India among which cereals were the largest producer of crop residue followed by sugarcane. The energy potential from paddy rice straw crop residue was estimated as 486,955 megawatt for 2014-15 and similarly for coarse cereals it was 226,200megawatt.

  15. Effect of pre-treatments on methane production potential of energy crops and crop residues

    Energy Technology Data Exchange (ETDEWEB)

    Lehtomaki, A.; Ronkainen; Rintala, J.A. [Jyvaskla Univ. (Finland). Dept. of Biological and Environmental Sciences; Viinikainen, T.A. [Jyvaskla Univ. (Finland). Dept. of Chemistry

    2004-07-01

    Energy crops, that is, crops grown specifically for energy purposes are an alternative to food production in areas with sufficient agricultural land. Crop residues are also a potential source of energy. The anaerobic digestion of solid materials is limited by hydrolysis of complex polymeric substances such as lignocellulose. The methane producing potential of ligno cellulosic material is to pretreat the substrate in order to break up the polymer chains to more easily accessible soluble compounds. In this study, three different substrates were used: sugar beet tops, grass hay, and straw of oats. Biological pretreatments were the following: enzyme treatment, composting, white-rot fungi treatment. Also, pretreatment in water was tried. Chemical pretreatments included peracetic acid treatment, and treatment with two different alkalis. Alkaline pretreatments of hay and sugar beet tops have the potential to improve the methane yield. For instance, the yield of grass hay was increased 15 per cent by one particular alkaline treatment. Straw did not respond to any of the treatments tried. 18 refs., 1 tab., 2 figs.

  16. Measurement of the fluorescence of crop residues: A tool for controlling soil erosion

    Science.gov (United States)

    Daughtry, C. S. T.; Mcmurtrey, J. E., III; Chappelle, E. W.; Hunter, W. J.

    1994-01-01

    Management of crop residues, the portion of a crop left in the field after harvest, is an important conservation practice for minimizing soil erosion and for improving water quality. Quantification of crop residue cover is required to evaluate the effectiveness of conservation tillage practices. Methods are needed to quantify residue cover that are rapid, accurate, and objective. The fluorescence of crop residue was found to be a broadband phenomenon with emission maxima at 420 to 495 nm for excitations of 350 to 420 nm. Soils had low intensity broadband emissions over the 400 to 690 nm region for excitations of 300 to 600 nm. The range of relative fluorescence intensities for the crop residues was much greater than the fluorescence observed of the soils. As the crop residues decompose their blue fluorescence values approach the fluorescence of the soil. Fluorescence techniques are concluded to be less ambiguous and better suited for discriminating crop residues and soils than reflectance methods. If properly implemented, fluorescence techniques can be used to quantify, not only crop residue cover, but also photosynthetic efficiency in the field.

  17. Modeling crop residue burning experiments to evaluate smoke emissions and plume transport

    Science.gov (United States)

    Crop residue burning is a common land management practice that results in emissions of a variety of pollutants with negative health impacts. Modeling systems are used to estimate air quality impacts of crop residue burning to support retrospective regulatory assessments and also ...

  18. Modeling crop residue burning experiments to evaluate smoke emissions and plume transport

    Science.gov (United States)

    Luxi Zhou; Kirk R. Baker; Sergey L. Napelenok; George Pouliot; Robert Elleman; Susan M. O' Neill; Shawn P. Urbanski; David C. Wong

    2018-01-01

    Crop residue burning is a common land management practice that results in emissions of a variety of pollutants with negative health impacts. Modeling systems are used to estimate air quality impacts of crop residue burning to support retrospective regulatory assessments and also for forecasting purposes. Ground and airborne measurements from a recent field experiment...

  19. Impact of crop residues on seed germination of native desert plants ...

    African Journals Online (AJOL)

    Crop residues produce allelochemicals that may inhibit seed germination of many weeds. In this study, I assessed the effect of aqueous extracts of three crop residues (radish, rocket and rhodes) on final germination percentage and germination rate of four desert plants recorded as weeds in the United Arab Emirates farms ...

  20. Weed management practice and cropping sequence impact on soil residual nitrogen

    Science.gov (United States)

    Inefficient N uptake by crops from N fertilization and/or N mineralized from crop residue and soil organic matter results in the accumulation of soil residual N (NH4-N and NO3-N) which increases the potential for N leaching. The objective of this study was to evaluate the effects of weed management ...

  1. Using genetically modified tomato crop plants with purple leaves for absolute weed/crop classification.

    Science.gov (United States)

    Lati, Ran N; Filin, Sagi; Aly, Radi; Lande, Tal; Levin, Ilan; Eizenberg, Hanan

    2014-07-01

    Weed/crop classification is considered the main problem in developing precise weed-management methodologies, because both crops and weeds share similar hues. Great effort has been invested in the development of classification models, most based on expensive sensors and complicated algorithms. However, satisfactory results are not consistently obtained due to imaging conditions in the field. We report on an innovative approach that combines advances in genetic engineering and robust image-processing methods to detect weeds and distinguish them from crop plants by manipulating the crop's leaf color. We demonstrate this on genetically modified tomato (germplasm AN-113) which expresses a purple leaf color. An autonomous weed/crop classification is performed using an invariant-hue transformation that is applied to images acquired by a standard consumer camera (visible wavelength) and handles variations in illumination intensities. The integration of these methodologies is simple and effective, and classification results were accurate and stable under a wide range of imaging conditions. Using this approach, we simplify the most complicated stage in image-based weed/crop classification models. © 2013 Society of Chemical Industry.

  2. Farmers Participatory Research in the Evaluation of Maize Crop Residues for Improved Dairy Cattle Production in Eastern Kenya

    International Nuclear Information System (INIS)

    Kiruiro, E.M.; Kariuki, I.W.; Kang'ara, J.; Ouma, O.

    1999-01-01

    Informal and formal surveys, and participatory rural appraisal conducted within the coffee land-use system of Embu District in Eastern Kenya identified feed shortage as a major constraint to increased dairy production on small holder farms. To address this constraint, a two-year (1996-1998) on-farm research project involving 20 farms in Manyatta division, Embu District was initiated with broad objectives of developing components technologies that would use maize crop residues. This was due to the recognition of the fact that the greatest potential for improving field availability would be in the exploitation of crop residues, especially those derived from maize, the main staple crop in the region. Based on these reality appropriate technologies that would offer viable offers for the use of crop residues were identified and discussed during workshops and meetings with farmers. Component technologies considered included drying of maize leaves after defoliation and post-harvest storage methods for dry maize stover. this paper discussed the results of the participatory research in context of farmers' involvement in the technology development, testing, evaluation and promotion. The study demonstrated that involving farmers in all stages of the research process, enhanced their interest and participation in the testing and subsequent adoption of appropriate technologies

  3. Suitability of peanut residue as a nitrogen source for a rye cover crop

    OpenAIRE

    Balkcom,Kipling Shane; Wood,Charles Wesley; Adams,James Fredrick; Meso,Bernard

    2007-01-01

    Leguminous winter cover crops have been utilized in conservation systems to partially meet nitrogen (N) requirements of succeeding summer cash crops, but the potential of summer legumes to reduce N requirements of a winter annual grass, used as a cover crop, has not been extensively examined. This study assessed the N contribution of peanut (Arachis hypogaea L.) residues to a subsequent rye (Secale cereale L.) cover crop grown in a conservation system on a Dothan sandy loam (fine-loamy, kaoli...

  4. Characterization of protein and carbohydrate mid-IR spectral features in crop residues

    Science.gov (United States)

    Xin, Hangshu; Zhang, Yonggen; Wang, Mingjun; Li, Zhongyu; Wang, Zhibo; Yu, Peiqiang

    2014-08-01

    To the best of our knowledge, a few studies have been conducted on inherent structure spectral traits related to biopolymers of crop residues. The objective of this study was to characterize protein and carbohydrate structure spectral features of three field crop residues (rice straw, wheat straw and millet straw) in comparison with two crop vines (peanut vine and pea vine) by using Fourier transform infrared spectroscopy (FTIR) technique with attenuated total reflectance (ATR). Also, multivariate analyses were performed on spectral data sets within the regions mainly related to protein and carbohydrate in this study. The results showed that spectral differences existed in mid-IR peak intensities that are mainly related to protein and carbohydrate among these crop residue samples. With regard to protein spectral profile, peanut vine showed the greatest mid-IR band intensities that are related to protein amide and protein secondary structures, followed by pea vine and the rest three field crop straws. The crop vines had 48-134% higher spectral band intensity than the grain straws in spectral features associated with protein. Similar trends were also found in the bands that are mainly related to structural carbohydrates (such as cellulosic compounds). However, the field crop residues had higher peak intensity in total carbohydrates region than the crop vines. Furthermore, spectral ratios varied among the residue samples, indicating that these five crop residues had different internal structural conformation. However, multivariate spectral analyses showed that structural similarities still exhibited among crop residues in the regions associated with protein biopolymers and carbohydrate. Further study is needed to find out whether there is any relationship between spectroscopic information and nutrition supply in various kinds of crop residue when fed to animals.

  5. Quantitative estimation of the fluorescent parameters for crop leaves with the Bayesian inversion

    Science.gov (United States)

    In this study, the fluorescent parameters of crop leaves were retrieved from the leaf hyperspectral measurements by inverting the FluorMODleaf model, which is a leaf-level fluorescence model that is based on the widely used and validated PROSPECT (leaf optical properties) model and can simulate the ...

  6. Artemisinin and sesquiterpene precursors in dead and green leaves of Artemisia annua L. crops

    NARCIS (Netherlands)

    Lommen, W.J.M.; Elzinga, S.; Verstappen, F.W.A.; Bouwmeester, H.J.

    2007-01-01

    This paper analyses the accumulation and concentrations of the antimalarial artemisinin in green and dead leaves of Artemisia annua crops in two field experiments. Concentration differences were analysed as being determined by (a) the total production of artemisinin plus its upstream precursors

  7. The Effect of Crop Residue Application to Soil Fauna Community and Mungbean Growth (Vigna radata

    Directory of Open Access Journals (Sweden)

    SUGIYARTO

    2000-01-01

    Full Text Available Litterbag experiment was carried out to determine the effect of crop residue application to soil fauna community and mungbean growth. The experiment arranged in randomized complete design with triplicate. The four treatment application of crotalarian, rice straw and banana’s aerial stem residues as well as without residue application as control. Soil fauna community and mungbean growth measured at 8 weeks after mungbean sown. Soil fauna extracted by modified Barless-Tullgren extractor apparatus. Height and dry weight of mungbean measured as crop growth parameters. The results indicated that the soil fauna densities and diversities as well as the growth of mungbean tended to increase by the application of crop residues. The effect of the treatment decreasing in the following order: banana’s aerial stem residue > crotalarian residue > rice straw > without residue application. There were high correlation between mungbean growth and soil fauna diversities.© 2001 Jurusan Biologi FMIPA UNS SurakartaKey words:

  8. Turnover of grain legume N rhizodeposits and effect of rhizodeposition on the turnover of crop residues

    DEFF Research Database (Denmark)

    Mayer, J.; Buegger, F.; Jensen, E.S.

    2004-01-01

    The turnover of N derived from rhizodeposition of faba bean (Vicia faba L.), pea (Pisum sativum L.) and white lupin (Lupinus albus L.) and the effects of the rhizodeposition on the subsequent C and N turnover of its crop residues were investigated in an incubation experiment (168 days, 15 degrees....... In the experiment the turnover of C and N was compared in soils with and without previous growth of three legumes and with and without incorporation of crop residues. After 168 days, 21% (lupin), 26% (faba bean) and 27% (pea) of rhizodeposition N was mineralised in the treatments without crop residues. A smaller...... amount of 15-17% was present as microbial biomass and between 30 and 55% of mineralised rhizodeposition N was present as microbial residue pool, which consists of microbial exoenzymes, mucous substances and dead microbial biomass. The effect of rhizodeposition on the C and N turnover of crop residues...

  9. Impact of crop residue management on crop production and soil chemistry after seven years of crop rotation in temperate climate, loamy soils.

    Science.gov (United States)

    Hiel, Marie-Pierre; Barbieux, Sophie; Pierreux, Jérôme; Olivier, Claire; Lobet, Guillaume; Roisin, Christian; Garré, Sarah; Colinet, Gilles; Bodson, Bernard; Dumont, Benjamin

    2018-01-01

    Society is increasingly demanding a more sustainable management of agro-ecosystems in a context of climate change and an ever growing global population. The fate of crop residues is one of the important management aspects under debate, since it represents an unneglectable quantity of organic matter which can be kept in or removed from the agro-ecosystem. The topic of residue management is not new, but the need for global conclusion on the impact of crop residue management on the agro-ecosystem linked to local pedo-climatic conditions has become apparent with an increasing amount of studies showing a diversity of conclusions. This study specifically focusses on temperate climate and loamy soil using a seven-year data set. Between 2008 and 2016, we compared four contrasting residue management strategies differing in the amount of crop residues returned to the soil (incorporation vs. exportation of residues) and in the type of tillage (reduced tillage (10 cm depth) vs. conventional tillage (ploughing at 25 cm depth)) in a field experiment. We assessed the impact of the crop residue management on crop production (three crops-winter wheat, faba bean and maize-cultivated over six cropping seasons), soil organic carbon content, nitrate ([Formula: see text]), phosphorus (P) and potassium (K) soil content and uptake by the crops. The main differences came primarily from the tillage practice and less from the restitution or removal of residues. All years and crops combined, conventional tillage resulted in a yield advantage of 3.4% as compared to reduced tillage, which can be partly explained by a lower germination rate observed under reduced tillage, especially during drier years. On average, only small differences were observed for total organic carbon (TOC) content of the soil, but reduced tillage resulted in a very clear stratification of TOC and also of P and K content as compared to conventional tillage. We observed no effect of residue management on the [Formula: see

  10. The Effect of Kaffir Lime Leaves Distillation Residue Oleoresin Concentration on Active Paper Packaging Characteristics

    Science.gov (United States)

    Kawiji; Utami, R.; Ulum, S.; Khasanah, L. U.; Manuhara, G. J.; Atmaka, W.

    2018-03-01

    Oleoresin of kaffir lime leaves distillation residue still contains some active compounds such as Citronellal, β-Citronellol, and Linalool which potential to incorporated on the active paper packaging. The purposes of this study were to determine the effect of kaffir lime leaves distillation residue oleoresin concentration on the physical characteristics, sensory characteristics, and antimicrobial activity of the active paper packaging incorporated with kaffir lime leaves distillation residue oleoresin and to determine the functional groups of active paper packaging. The concentration of kaffir lime leaves distillation residue oleoresin were varied at 0%, 2%, 4% and 6%. The result showed that the addition of kaffir lime leaves distillation residue oleoresin increased the thickness and moisture content of the paper and decreased the tensile strengths and folding endurances of active paper packaging. The microbial inhibition tends to increase along with the higher oleoresin concentration addition. Aromatic CH group were found at a wavelength of 897.90 cm-1 of on paper packaging with 2% oleoresin indicated as functional aromatic functional group allegedly obtained from the kaffir lime leaves oleoresin.

  11. Crop residue inventory estimates for Texas High Plains cotton

    Science.gov (United States)

    Interest in the use of cotton crop by-products for the production of bio-fuels and value-added products is increasing. Research documenting the availability of cotton crop by-products after machine harvest is needed. The objectives of this work were to document the total biomass production for moder...

  12. The effect of crop residue layers on evapotranspiration, growth and ...

    African Journals Online (AJOL)

    Observations of crop growth (stalk population, stalk height, canopy cover), cane yield and evapotranspiration for these treatments were compared to that of a bare soil treatment. The data were also used to derive values of crop evaporation coefficients for different development phases and these were compared to FAO56 ...

  13. Impact of crop residue management on crop production and soil chemistry after seven years of crop rotation in temperate climate, loamy soils

    Directory of Open Access Journals (Sweden)

    Marie-Pierre Hiel

    2018-05-01

    Full Text Available Society is increasingly demanding a more sustainable management of agro-ecosystems in a context of climate change and an ever growing global population. The fate of crop residues is one of the important management aspects under debate, since it represents an unneglectable quantity of organic matter which can be kept in or removed from the agro-ecosystem. The topic of residue management is not new, but the need for global conclusion on the impact of crop residue management on the agro-ecosystem linked to local pedo-climatic conditions has become apparent with an increasing amount of studies showing a diversity of conclusions. This study specifically focusses on temperate climate and loamy soil using a seven-year data set. Between 2008 and 2016, we compared four contrasting residue management strategies differing in the amount of crop residues returned to the soil (incorporation vs. exportation of residues and in the type of tillage (reduced tillage (10 cm depth vs. conventional tillage (ploughing at 25 cm depth in a field experiment. We assessed the impact of the crop residue management on crop production (three crops—winter wheat, faba bean and maize—cultivated over six cropping seasons, soil organic carbon content, nitrate ( ${\\mathrm{NO}}_{3}^{-}$ NO 3 − , phosphorus (P and potassium (K soil content and uptake by the crops. The main differences came primarily from the tillage practice and less from the restitution or removal of residues. All years and crops combined, conventional tillage resulted in a yield advantage of 3.4% as compared to reduced tillage, which can be partly explained by a lower germination rate observed under reduced tillage, especially during drier years. On average, only small differences were observed for total organic carbon (TOC content of the soil, but reduced tillage resulted in a very clear stratification of TOC and also of P and K content as compared to conventional tillage. We observed no effect of residue

  14. Global warming impact assessment of a crop residue gasification project—A dynamic LCA perspective

    International Nuclear Information System (INIS)

    Yang, Jin; Chen, Bin

    2014-01-01

    Highlights: • A dynamic LCA is proposed considering time-varying factors. • Dynamic LCA is used to highlight GHG emission hotspots of gasification projects. • Indicators are proposed to reflect GHG emission performance. • Dynamic LCA alters the static LCA results. • Crop residue gasification project has high GHG abatement potential. - Abstract: Bioenergy from crop residues is one of the prevailing sustainable energy sources owing to the abundant reserves worldwide. Amongst a wide variety of energy conversion technologies, crop residue gasification has been regarded as promising owing to its higher energy efficiency than that of direct combustion. However, prior to large-scale application of crop residue gasification, the lifetime environmental performance should be investigated to shed light on sustainable strategies. As traditional static life cycle assessment (LCA) does not include temporal information for dynamic processes, we proposed a dynamic life cycle assessment approach, which improves the static LCA approach by considering time-varying factors, e.g., greenhouse gas characterization factors and energy intensity. As the gasification project can reduce greenhouse gas (GHG) discharge compared with traditional direct fuel combustion, trade-offs between the benefits of global warming mitigation and the impact on global warming of crop residue gasification should be considered. Therefore, indicators of net global warming mitigation benefit and global warming impact mitigation period are put forward to justify the feasibility of the crop residue gasification project. The proposed dynamic LCA and indicators were then applied to estimate the life cycle global warming impact of a crop residue gasification system in China. Results show that the crop residue gasification project has high net global warming mitigation benefit and a short global warming impact mitigation period, indicating its prominent potential in alleviating global warming impact. During

  15. Economic factors influencing potential use of cellulosic crop residues for electricity generation

    International Nuclear Information System (INIS)

    Maung, Thein A.; McCarl, Bruce A.

    2013-01-01

    This study examines cellulosic crop residues for biopower production in the context of (greenhouse gas) GHG emission mitigation. We employ sector modeling to simulate future market potential for biopower production from crop residues. Our findings suggest that in order for crop residues to have any role in electricity generation either the carbon or (carbon dioxide) CO 2 equivalent GHG price must rise to about 15 dollars per ton or the price of coal has to increase to about 43 dollars per ton. We find that crop residues with higher heat content have greater opportunities in biopower production than the residues with lower heat content. In addition, our evidence shows that improvements in crop yields do not have much impact on biopower production. However, the energy recovery efficiency does have significant positive impact but only if the CO 2 equivalent price rises substantially. Moreover, our analysis indicates the desirability of cofiring biomass as opposed to 100% replacement because this reduces transportation cost and increases the efficiency of heat recovery. In terms of policy implications, imposing carbon emission pricing could be an important step in inducing electric power producers to include biomass feedstocks in their fuel-mix power generation portfolios and achieve GHG emission reductions. - Highlights: • Crop residues with higher heat content have greater market opportunities. • Improvement in crop and residue yields does not have much impact on biopower production. • Advancement in biopower production technology does not encourage more use of crop residues. • The main factor that induces biopower production is an increase in future carbon prices

  16. Crop residue is key for sustaining maximum food production and for conservation of our biosphere

    Science.gov (United States)

    Crop residue is key in our efforts to move towards agricultural sustainability. This paper provides a quick overview of some selected references and looks at some of the newest advances related to cover crops. Several authors have described in detail the benefits derived from improving soil quality ...

  17. Erratum to: Estimating the crop response to fertilizer nitrogen residues in long-continued field experiments

    DEFF Research Database (Denmark)

    Petersen, Jens; Thomsen, Ingrid Kaag; Mattson, L

    2012-01-01

    Knowledge of the cumulated effect of long-continued nitrogen (N) inputs is important for both agronomic and environmental reasons. However, only little attention has been paid to estimate the crop response to mineral fertilizer N residues. Before interpreting estimates for the crop response...

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

    Science.gov (United States)

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

    2013-04-01

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

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

    Directory of Open Access Journals (Sweden)

    A. Zarea Feizabadi

    2016-07-01

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

  20. Assessing the Effect of Prometryn Soil Residue on Soil Microbial Biomass and Different Crops using Bioassay Test

    Directory of Open Access Journals (Sweden)

    mohamad taghi alebrahim

    2016-09-01

    Full Text Available Introduction: Herbicides are the most widely used of chemical pesticides for agricultural production and landscape management. The environmental risk of herbicides should be evaluated near sites of application, even though basic ecotoxicological tests have been conducted before they can be registered for marketing. For example, triazine herbicides, which are photosynthetic PSII herbicide that considered only slightly or moderately toxic to many susceptible plants, soil microorganisms, mammals and humans, however, concerns have arisen because this herbicide are members of a class claimed to be carcinogenic, or may affect the development as reproductive toxins. For this reason, most reliable evidence is needed to test these claims and investigate their ecological effects. Prometryn is a herbicide belongs to triazine family that may leave residual activity in the soil for extended periods, causing injury and yield reduction of susceptible soil microorganisms and crops in rotation. Compared with other methods, the rapidity of response, sensitivity, high level of precision, simple process and easy operation are the advantages of bioassay methods for the routine monitoring of biologically available photosynthesis-inhibiting herbicides present in agricultural soils. Materials and Methods: A pot experiment was conducted under greenhouse conditions in order to study the sensitivity of 4 different crops to prometryn soil residue at the College of Agricultural Sciences, Ilam University, Ilam, Iran in 2014. Experimental type was completely randomized design in a factorial arrangement with three replications. Treatments included 4 different crops (lettuce, barley, rapeseed and beet and prometryn simulated concentrations residues in soil (0.0033, 0.0166, 0.033, 0.066, 0.1 and 0.166 mg. kg-1soil. 15 cm diameter pots were filled with a modified soil and 10 of seeds of crops were planted in 5 regular positions. The plants were thinned to five plants per pot

  1. Soil fertility and soil loss constraints on crop residue removal for energy production

    Energy Technology Data Exchange (ETDEWEB)

    Flaim, S.

    1979-07-01

    A summary of the methodologies used to estimate the soil fertility and soil loss constraints on crop residue removal for energy production is presented. Estimates of excess residue are developed for wheat in north-central Oklahoma and for corn and soybeans in central Iowa. These sample farming situations are analyzed in other research in the Analysis Division of the Solar Energy Research Institute.

  2. Utilization of residual nitrogen (15N) from cover crop and urea by corn

    International Nuclear Information System (INIS)

    Silva, Edson Cabral da; Muraoka, Takashi; Trivelin, Paulo Cesar Ocheuze; Buzetti, Salatier; Veloso, Marcos Emanuel da Costa

    2006-01-01

    The majority of N from mineral fertilizers and cover crops is usually not used by the very next corn crop, but can be absorbed by follow-up crops. The objective of this study was to evaluate the use of residual nitrogen from urea, sunnhemp (Crotalaria juncea) and millet (Pennisetum americanum) labeled with 15 N, applied to no-tillage corn in the previous growing season, in a Red Latosol of the Cerrado. The study was conducted in an experimental farm of the Sao Paulo State University (UNESP), Ilha Solteira, in Selviria county (MS), Brazil, in different areas. The experiment had a randomized complete block design, with 15 treatments and four replications. Treatments were applied to corn crop in the 2001/02 and 2003/04 growing seasons. They were distributed in a 3 x 5 factorial layout, representing the combination of three cover crops: sunnhemp, millet and spontaneous vegetation (fallow) and five N rates (as urea): 0, 30, 80, 130, and 180 kg ha-1 of N. After corn harvest, the two areas were followed in the dry season and were followed by corn crop in the 2002/03 (experiment 1) and 2003/04 (experiment 2) growing seasons, using the same fertilizer rate on all plots to distinguish the residual effect of N sources. The average use of residual N from the millet and sunnhemp residues (above-ground part) by corn crop was less than 3.5 and 3 %, respectively, of the initial amount. The corn uptake of residual N from urea increased in a quadratic manner in experiment 1 and linearly in experiment Two as a response to the applied N rates, and the recover was below 3 %. The cover crop type did not affect the use of residual N of urea by corn, and vice-versa. (author)

  3. Release of Phosphorus Forms from Cover Crop Residues in Agroecological No-Till Onion Production

    Directory of Open Access Journals (Sweden)

    Rodolfo Assis de Oliveira

    Full Text Available ABSTRACT Cover crops grown alone or in association can take up different amounts of phosphorus (P from the soil and accumulate it in different P-forms in plant tissue. Cover crop residues with a higher content of readily decomposed forms may release P more quickly for the next onion crop. The aim of this study was to evaluate the release of P forms from residues of single and mixed cover crops in agroecological no-till onion (Allium cepa L. production. The experiment was conducted in Ituporanga, Santa Catarina (SC, Brazil, in an Inceptisol, with the following treatments: weeds, black oat (Avena sativa L., rye (Secale cereale L., oilseed radish (Raphanus sativus L., oilseed radish + black oat, and oilseed radish + rye. Cover crops were sown in April 2013. In July 2013, plant shoots were cut close to the soil surface and part of the material was placed in litterbags. The bags were placed on the soil surface and residues were collected at 0, 15, and 45 days after deposition (DAD. Residues were dried and ground and P in the plant tissue was determined through chemical fractionation. The release of P contained in the tissue of cover crops depends not only on total P content in the tissue, but also on the accumulation of P forms and the quality of the residue in decomposition. The highest accumulation of P in cover crops occurred in the soluble inorganic P fraction, which is the fraction of fastest release in plants. Black oat had the highest initial release rate of soluble inorganic P, which became equal to the release rate of other cover crop residues at 45 DAD. Weeds released only half the amount of soluble inorganic P in the same period, despite accumulating a considerable amount of P in their biomass. The mixtures of oilseed radish + rye and oilseed radish + black oat showed higher release of P associated with RNA at 45 DAD in comparison to the single treatments.

  4. Nitrogen mineralization from selected 15N-labelled crop residues and humus as affected by inorganic nitrogen

    International Nuclear Information System (INIS)

    Santos, J.A.

    1987-01-01

    The use of cover crops or crop residues as a source of N to succeeding crops has become a matter of increasing importance for economic and environmental reason. Greenhouse and field studies were conducted to determine the N contribution of four 15 N labelled crop residues, rye (Secale cereale L.), wheat (Triticum aestivum L.), crimson clover (Trifolium encarnatum L.), and hairy vetch (Vicia sativa L.), to successive crops and to evaluate the effect of different organic (ON) and inorganic N (IN) combinations on mineralization of the above residues. Total 15 N recovery from the residues ranged from 51% to 85% and 4% to 74% for the greenhouse and field studies, respectively

  5. Spatial Variability Mapping of Crop Residue Using Hyperion (EO-1 Hyperspectral Data

    Directory of Open Access Journals (Sweden)

    Abderrazak Bannari

    2015-06-01

    Full Text Available Soil management practices that maintain crop residue cover and reduce tillage improve soil structure, increase organic matter content in the soil, positively influence water infiltration, evaporation and soil temperature, and play an important role in fixing CO2 in the soil. Consequently, good residue management practices on agricultural land have many positive impacts on soil quality, crop production quality and decrease the rate of soil erosion. Several studies have been undertaken to develop and test methods to derive information on crop residue cover and soil tillage using empirical and semi-empirical methods in combination with remote sensing data. However, these methods are generally not sufficiently rigorous and accurate for characterizing the spatial variability of crop residue cover in agricultural fields. The goal of this research is to investigate the potential of hyperspectral Hyperion (Earth Observing-1, EO-1 data and constrained linear spectral mixture analysis (CLSMA for percent crop residue cover estimation and mapping. Hyperion data were acquired together with ground-reference measurements for validation purposes at the beginning of the agricultural season (prior to spring crop planting in Saskatchewan (Canada. At this time, only bare soil and crop residue were present with no crop cover development. In order to extract the crop residue fraction, the images were preprocessed, and then unmixed considering the entire spectral range (427 nm–2355 nm and the pure spectra (endmember. The results showed that the correlation between ground-reference measurements and extracted fractions from the Hyperion data using CLMSA showed that the model was overall a very good predictor for crop residue percent cover (index of agreement (D of 0.94, coefficient of determination (R2 of 0.73 and root mean square error (RMSE of 8.7% and soil percent cover (D of 0.91, R2 of 0.68 and RMSE of 10.3%. This performance of Hyperion is mainly due to the

  6. Nitrogen accumulation and residual effects of nitrogen catch crops

    DEFF Research Database (Denmark)

    Jensen, E.S.

    1991-01-01

    The nitrogen accumulation in Italian ryegrass (Lolium multiflorum Lam.), perennial ryegrass (Lolium perenne L.), white mustard (Sinapis alba L.) and tansy phacelia (Phacelia tanacetifolia L.), under- or aftersown as nitrogen catch crops to spring barley (Hordeum vulgare L.) and field pea (Pisum s...

  7. Crop residue harvest for bioenergy production and its implications on soil functioning and plant growth: A review

    Directory of Open Access Journals (Sweden)

    Maurício Roberto Cherubin

    Full Text Available ABSTRACT: The use of crop residues as a bioenergy feedstock is considered a potential strategy to mitigate greenhouse gas (GHG emissions. However, indiscriminate harvesting of crop residues can induce deleterious effects on soil functioning, plant growth and other ecosystem services. Here, we have summarized the information available in the literature to identify and discuss the main trade-offs and synergisms involved in crop residue management for bioenergy production. The data consistently showed that crop residue harvest and the consequent lower input of organic matter into the soil led to C storage depletions over time, reducing cycling, supply and availability of soil nutrients, directly affecting the soil biota. Although the biota regulates key functions in the soil, crop residue can also cause proliferation of some important agricultural pests. In addition, crop residues act as physical barriers that protect the soil against raindrop impact and temperature variations. Therefore, intensive crop residue harvest can cause soil structure degradation, leading to soil compaction and increased risks of erosion. With regard to GHG emissions, there is no consensus about the potential impact of management of crop residue harvest. In general, residue harvest decreases CO2 and N2O emissions from the decomposition process, but it has no significant effect on CH4 emissions. Plant growth responses to soil and microclimate changes due to crop residue harvest are site and crop specific. Adoption of the best management practices can mitigate the adverse impacts of crop residue harvest. Longterm experiments within strategic production regions are essential to understand and monitor the impact of integrated agricultural systems and propose customized solutions for sustainable crop residue management in each region or landscape. Furthermore, private and public investments/cooperations are necessary for a better understanding of the potential environmental

  8. Residues and accumulation of molinate in rice crops and aquatic weeds in the MUDA rice agroecosystem

    International Nuclear Information System (INIS)

    Nashriyah Mat; Sabri Junoh; Nuriati Nurdin; Ramli Ishak

    2002-01-01

    Plant and soil residue levels and its accumulation in rice crops and rice aquatic weed plants were studied. Molinate residue levels in rice, weeds and soil were not significantly different between the recycled and the non-recycled area, even though they were higher in the non-recycled area. In the rice plant, the residue level at 10 DAT (days after treatment) was significantly higher than 30 DAT in the recycled area. In rice aquatic weed plants, the residue level was significantly higher at 10 DAT as compared to 30 DAT in the non-recycled area. Molinate residue levels in soil at 10 DAT and 30 DAT were similar. Molinate accumulated (ratio of molinate concentration in plant over soil) more in the rice crop as compared to rice aquatic weeds at 10 DAT, in both the recycled and the non-recycled areas. (Author)

  9. Preferency of soil macrofauna to crops residue at different light intensity

    Directory of Open Access Journals (Sweden)

    SUGIYARTO

    2007-10-01

    Full Text Available Every species of soil macrofauna prefer specific food and environment to be establish in it's habitat. Their diversity depend on variation of food and environmental condition. The aim of this research was to study the effect of different crop residue and light intensity on population of several soil macrofauna specieses. Mycrocosmos experiment was arranged in split-plot design with two treatments factor, i.e.: (1 crop residue (albizia, papaya, elephant grass, maize, sweet potato and without crop residue input, and (2 light intensities (0, 5, 15 and 25 Watt/day. The soil macrofauna were earthworms, millipedes, scarabids larvae and cocroachs. Results of the study showed that: (1 crop residues apllication increased soil macrofauna population, especially maize residue ( by 113%, respectively, compare to control tretment, (2 on higher light intensity, population of earthworms, scarabids larvae and cocroach decreased, but population of millipedes increased, (3 the highest macrofauna population was on maize residue and 5 Watt/day light intensity treatment.

  10. EFFECT OF DIFFERENT COVER CROP RESIDUES, MANAGEMENT PRACTICES ON SOIL MOISTURE CONTENT UNDER A TOMATO CROP (LYCOPERSICON ESCULENTUM

    Directory of Open Access Journals (Sweden)

    George Njomo Karuku

    2014-12-01

    Full Text Available SUMMARYThe soil water storage, soil water content, available water content and soil water balance under various cover crop residue management practices in a Nitisol were evaluated in a field experiment at the Kabete Field Station, University of Nairobi. The effects of surface mulching, above and below ground biomass and roots only incorporated of (mucuna pruriens, Tanzanian sunnhemp (Crotalaria ochroleuca and Vetch (Vicia benghalensis cover crops, fertilizer and non fertilized plots on soil water balance were studied. Tomato (Lycopersicon esculentum was used as the test crop. Since water content was close to field capacity, the drainage component at 100 cm soil depth was negligible and evapotranspiration was therefore derived from the change in soil moisture storage and precipitation. Residue management showed that above and below ground biomass incorporated optimized the partitioning of the water balance components, increasing moisture storage, leading to increased tomato yields and water use efficiency. Furthermore, vetch above and below ground biomass incorporated significantly improved the quantity and frequency of deep percolation. Soil fertilization (F and non fertilization (NF caused the most unfavourable partitioning of water balance, leading to the lowest yield and WUE. Tomato yields ranged from 4.1 in NF to 7.4 Mg ha-1 in Vetch treated plots. Vetch above and belowground biomass incorporated had significant (p ≤ 0.1 yields of 11.4 Mg ha-1 compared to all other residue management systems. Vetch residue treatment had the highest WUE (22.7 kg mm-1 ha-1 followed by mucuna treated plots (20.7 kg mm-1 ha-1 and both were significantly different (p ≤ 0.05 compared to the others irrespective of residue management practices.

  11. Effect of water content and organic carbon on remote sensing of crop residue cover

    Science.gov (United States)

    Serbin, G.; Hunt, E. R., Jr.; Daughtry, C. S. T.; McCarty, G. W.; Brown, D. J.; Doraiswamy, P. C.

    2009-04-01

    Crop residue cover is an important indicator of tillage method. Remote sensing of crop residue cover is an attractive and efficient method when compared with traditional ground-based methods, e.g., the line-point transect or windshield survey. A number of spectral indices have been devised for residue cover estimation. Of these, the most effective are those in the shortwave infrared portion of the spectrum, situated between 1950 and 2500 nm. These indices include the hyperspectral Cellulose Absorption Index (CAI), and advanced multispectral indices, i.e., the Lignin-Cellulose Absorption (LCA) index and the Shortwave Infrared Normalized Difference Residue Index (SINDRI), which were devised for the NASA Terra Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor. Spectra of numerous soils from U.S. Corn Belt (Indiana and Iowa) were acquired under wetness conditions varying from saturation to oven-dry conditions. The behavior of soil reflectance with water content was also dependent on the soil organic carbon content (SOC) of the soils, and the location of the spectral bands relative to significant water absorptions. High-SOC soils showed the least change in spectral index values with increase in soil water content. Low-SOC soils, on the other hand, showed measurable difference. For CAI, low-SOC soils show an initial decrease in index value followed by an increase, due to the way that water content affects CAI spectral bands. Crop residue CAI values decrease with water content. For LCA, water content increases decrease crop residue index values and increase them for soils, resulting in decreased contrast. SINDRI is also affected by SOC and water content. As such, spatial information on the distribution of surface soil water content and SOC, when used in a geographic information system (GIS), will improve the accuracy of remotely-sensed crop residue cover estimates.

  12. Effect of tillage and crop residue management on nematode densities on corn.

    Science.gov (United States)

    McSorley, R; Gallaher, R N

    1994-12-01

    Effects of winter cover crop management on nematode densities associated with a subsequent corn (Zea mays) crop were examined in five sites in north Florida. Two sites had received winter cover crops of lupine (Lupinus angustifolius), and one site each had rye (Secale cereale), hairy vetch (Vicia villosa), and crimson clover (Trifolium incarnatum). In each site, five different management regimes were compared: 1) conventional tillage after the cover crop was removed for forage; 2) conventional tillage with the cover crop retained as green manure; 3) no-till with the cover crop mowed and used as a mulch; 4) no-till with the cover crop removed as forage; and 5) fallow. Sites were sampled at corn planting and harvest for estimates of initial (Pi) and final (Pf) nematode population densities, respectively. Whether the cover crop was removed as forage or retained as green manure or mulch had no effect (P > 0.10) on population densities of any plant-parasitic nematode before or after corn at any site. Differences between conventional-till and no-till treatments were significant (P cover crop residues had little consistent effect on nematodes, and these practices should be considered based on agronomic benefits rather than for nematode management.

  13. Improved crop residue cover estimates by coupling spectral indices for residue and moisture

    Science.gov (United States)

    Remote sensing assessment of soil residue cover (fR) and tillage intensity will improve our predictions of the impact of agricultural practices and promote sustainable management. Spectral indices for estimating fR are sensitive to soil and residue water content, therefore, the uncertainty of estima...

  14. Distribution, utilization structure and potential of biomass resources in rural China: With special references of crop residues

    Energy Technology Data Exchange (ETDEWEB)

    Liu, H [Laboratory of Quantitative Vegetation Ecology, Institute of Botany, Chinese Academy of Sciences, 20 Nanxincun, Xiangshan, Beijing 100093 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Jiang, G M [Laboratory of Quantitative Vegetation Ecology, Institute of Botany, Chinese Academy of Sciences, 20 Nanxincun, Xiangshan, Beijing 100093 (China); Agronomy Department, Shandong Agricultural University, Tai' an 271018, Shandong Province (China); Zhuang, H Y [National Bio-Energy CO., LTD, No. 26B, Financial Street, Xicheng District, Beijing 100032 (China); Shandong Academy of Sciences, No. 19, Keyuan Road, Ji' nan 250014, Shandong Province (China); Wang, K J [Agronomy Department, Shandong Agricultural University, Tai' an 271018, Shandong Province (China)

    2008-06-15

    As the largest developing country in the world, China is urgently in short of energy and natural resources. However, biological resources such as crop residues are burnt in the field, which cause serious environmental pollution. Still it is not clear how much storage and potential of these huge crop residues are in China. This paper firstly reported the distribution, utilization structure and potential of crop biomass and provided the tangible information of crop residues in rural China through careful collecting and recalculating data. From 1995 to 2005, China produces some 630 million tons of crop residues per year, 50% of which comes from east and central south of China. The amount of crop residues is 1.3 times of the total yield of crops, 2 times of the total fodder of grassland, which covers 41% of China's territory. Crop residues of corn, wheat and rice amounted to 239, 137 and 116 million tons, respectively, accounting for nearly 80% of the total crop residues. Unfortunately, the utilizing structure is seriously improper for such abundant biomass resources. Although 23% of the crop residues are used for forage, 4% for industry materials and 0.5% for biogas, the large parts are used with lower efficiency or wasted, with 37% being directly combusted by farmers, 15% lost during collection and the rest 20.5% discarded or directly burnt in the field. Reasonable adjustment of the utilizing pattern and popularization of the recycling agriculture are essential out-ways for residues, with the development of the forage industry being the breakthrough point. We suggested that utilizing the abandoned 20.5% of the total residues for forage and combining agriculture and stock raising can greatly improve the farm system and cut down fertilizer pollution. Through the development of forage industries, the use efficiency of crop residues could be largely enhanced. Commercializing and popularizing technologies of biomass gasification and liquefaction might be substitute

  15. Neutralization of acidic raindrops on leaves of agricultural crop and boreal forest species

    Energy Technology Data Exchange (ETDEWEB)

    Hutchinson, T.C.; Adams, C.M.; Gaber, B.A.

    1986-10-01

    The abilities of foliage of selected agricultural crop and native boreal forest species to neutralize acidic raindrops were compared. The species differed widely in their responses. Neutralization was influenced to a large extent by leaf wettability and was poorly related with species' susceptibility to foliar injury from acid rain sprayings. Little neutralization of pH 3.0 droplets occurred on very waxy leaves, e.g. cabbage (Brassica oleracea L.), due to the small contact area between the leaf surface and raindrops. In contrast, on sunflower (Helianthus annuus L.) and radish (Raphanus sativus L.) leaves, which are pubescent and easily wettable, neutralization was considerable. For all agricultural crop species examined, the pH of droplets drying on cotyledons was consistently higher than on the leaves. The pH values of raindrops were also higher when the foliage was injured by the acid rain, probably due to leakage of cellular contents. Among boreal forest species examined, bunchberry (Cornus canadensis L.) was particularly good at neutralizing natural acid rain, increasing the pH from 3.9 to 6.6 after 9 hr of foliar contact, while the response of other boreal species ranged from a final pH of 4.8 to 5.7 under the same conditions. Simulated raindrops on wild sarsaparilla (Aralia nudicaulis L.) were never neutralized but increased in acidity as they evaporated. Chemical analyses of droplets collected from foliage showed calcium (Ca) and potassium (K) to be the major cations entering the neutralized droplets. Neutralization of acidic raindrops appears to occur through two processes; solubilization of alkaline dusts and exudates on the leaf surface, and ion exchange removal of H/sup +/ by the foliage. 14 references.

  16. Neutralization of acidic raindrops on leaves of agricultural crop and boreal forest species

    Energy Technology Data Exchange (ETDEWEB)

    Hutchinson, T.C.; Adams, C.M.; Gaber, B.A.

    1986-11-01

    The abilities of foliage of selected agricultural crop and native boreal forest species to neutralize acidic raindrops were compared. The species differed widely in their responses. Neutralization was influenced to a large extent by leaf wettability and was poorly related with species' susceptibility to foliar injury from acid rain sprayings. Little neutralization of pH 3.0 droplets occurred on very waxy leaves, e.g. cabbage (Brassica oleracea L.), due to the small contact area between the leaf surface and raindrops. In contrast, on sunflower (Helianthus annuus L.) and radish (Raphanus sativus L.) leaves, which are pubescent and easily wettable, neutralization was considerable. For all agricultural crop species examined, the pH of droplets drying on cotyledons was consistently higher than on the leaves. The pH values of raindrops were also higher when the foliage was injured by the acid rain, probably due to leakage of cellular contents. Among boreal forest species examined, bunchberry (Cornus canadensis L.) was particularly good at neutralizing natural acid rain, increasing the pH from 3.9 to 6.6 after 9 hr of foliar contact, while the response of other boreal species ranged from a final pH of 4.8 to 5.7 under the same conditions. Simulated raindrops on wild sarsaparilla (Aralia nudicaulis L.) were never neutralized but increased in acidity as they evaporated. Chemical analyses of droplets collected from foliage showed calcium and potassium to be the major cations entering the neutralized droplets. Neutralization of acidic raindrops appears to occur through two processes: solubilization of alkaline dusts and exudates on the leaf surface, and ion exchange removal of H/sup +/ by the foliage. 14 refs.

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

    Science.gov (United States)

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

  18. Nitrous oxide emissions and controls as influenced by tillage and crop residue management strategy

    DEFF Research Database (Denmark)

    Mutegi, James; Munkholm, Lars Juhl; Petersen, Bjørn Molt

    2010-01-01

    (RT) or conventional tillage (CT). Each of these tillage treatments further varied in respect to whether the resulting plot crop residues were retained (+Res) or removed (-Res). Sampling took place from autumn 2007 to the end of spring 2008. Overall N2O emissions were 27 and 26% lower in DD and RT...

  19. Use of a portable time-resolved fluorometer to determine oxytetracycline residue in four fruit crops

    Science.gov (United States)

    Worldwide, oxytetracycline (OTC) is used in fruit and vegetable crops to prevent and treat bacteria diseases. In the U.S., the Environmental Protection Agency approved its use in apple, pear, peach, and nectarine, and set tolerance at 350 ng/g. OTC residues in 12 varieties of these fruits are determ...

  20. Spatio-temporal availability of field crop residues for biofuel production in Northwest and Southwest China

    NARCIS (Netherlands)

    Han, L.; Wang, X.; Spiertz, J.H.J.; Yang, L.; Zhou, Y.; Liu, J.; Xie, G.

    2015-01-01

    Developing bioenergy from plant feedstocks is considered an opportunity to reduce greenhouse gas emissions and secure biofuel supply. This study is an assessment of the availability of field crop residues for bioenergy feedstocks in northwest China (NWC) and southwest China (SWC). The amount of

  1. The 2014 National Emission Inventory for Rangeland Fires and Crop Residue Burning

    Science.gov (United States)

    Biomass burning has been identified as an important contributor to the degradation of air quality because of its impact on ozone and particulate matter. One component of the biomass burning inventory, crop residue burning, has been poorly characterized in the National Emissions I...

  2. Short-term contributions of cover crop surface residue return to soil carbon and nitrogen contents in temperate Australia.

    Science.gov (United States)

    Zhou, Xiaoqi; Wu, Hanwen; Li, Guangdi; Chen, Chengrong

    2016-11-01

    Cover crop species are usually grown to control weeds. After cover crop harvest, crop residue is applied on the ground to improve soil fertility and crop productivity. Little information is available about quantifying the contributions of cover crop application to soil total carbon (C) and nitrogen (N) contents in temperate Australia. Here, we selected eight cover crop treatments, including two legume crops (vetch and field pea), four non-legume crops (rye, wheat, Saia oat, and Indian mustard), a mixture of rye and vetch, and a nil-crop control in temperate Australia to calculate the contributions of cover crops (crop growth + residue decomposition) to soil C and N contents. Cover crops were sown in May 2009 (autumn). After harvest, the crop residue was placed on the soil surface in October 2009. Soil and crop samples were collected in October 2009 after harvest and in May 2010 after 8 months of residue decomposition. We examined cover crop residue biomass, soil and crop total C and N contents, and soil microbial biomass C and N contents. The results showed that cover crop application increased the mean soil total C by 187-253 kg ha -1 and the mean soil total N by 16.3-19.1 kg ha -1 relative to the nil-crop treatment, except for the mixture treatment, which had similar total C and N contents to the nil-crop control. Cover crop application increased the mean soil microbial biomass C by 15.5-20.9 kg ha -1 and the mean soil microbial biomass N by 4.5-10.2 kg ha -1 . We calculated the apparent percentage of soil total C derived from cover crop residue C losses and found that legume crops accounted for 10.6-13.9 %, whereas non-legume crops accounted for 16.4-18.4 % except for the mixture treatment (0.2 %). Overall, short-term cover crop application increased soil total C and N contents and microbial biomass C and N contents, which might help reduce N fertilizer use and improve sustainable agricultural development.

  3. Beliefs about emotional residue: the idea that emotions leave a trace in the physical environment.

    Science.gov (United States)

    Savani, Krishna; Kumar, Satishchandra; Naidu, N V R; Dweck, Carol S

    2011-10-01

    Drawing upon the literatures on beliefs about magical contagion and property transmission, we examined people's belief in a novel mechanism of human-to-human contagion, emotional residue. This is the lay belief that people's emotions leave traces in the physical environment, which can later influence others or be sensed by others. Studies 1-4 demonstrated that Indians are more likely than Americans to endorse a lay theory of emotions as substances that move in and out of the body, and to claim that they can sense emotional residue. However, when the belief in emotional residue is measured implicitly, both Indians and American believe to a similar extent that emotional residue influences the moods and behaviors of those who come into contact with it (Studies 5-7). Both Indians and Americans also believe that closer relationships and a larger number of people yield more detectable residue (Study 8). Finally, Study 9 demonstrated that beliefs about emotional residue can influence people's behaviors. Together, these finding suggest that emotional residue is likely to be an intuitive concept, one that people in different cultures acquire even without explicit instruction. 2011 APA, all rights reserved

  4. Utilization of tropical crop residues and agroindustrial by-products in animal nutrition. Constraints and perspectives

    International Nuclear Information System (INIS)

    Preston, T.R.; Parra, R.

    1983-01-01

    The importance of by-products and crop residues as animal feeds is increasing steadily. This is a consequence of the increasing demand for cereal grains as both human and animal (chiefly poultry) food, and the increasing demand for energy coupled with decreasing availability of fossil fuels. The effects of these two trends are that primary use of land for livestock production (usually grazing systems) will steadily diminish; at the same time, sources of biomass will increase in importance as renewable energy sources, and greater emphasis will be placed on draught animal power. Most by-products and crop residues are fibrous and therefore of only low to moderate nutritive value, or have special physical and chemical characteristics making them difficult to incorporate in conventional ''balanced'' rations. Such feed raw materials may need special processing and/or special forms of supplementation if they are to be used efficiently. It is hypothesized that industrial by-products and crop residues will be more efficiently utilized if they are incorporated in diversified and integrated production systems, i.e. (a) livestock production is integrated with production of cash crops both for food and fuel; (b) different livestock species are utilized in the same enterprise in a complementary way; (c) livestock feeding is based on crop residues (energy) supplemented with protein-rich forages and aquatic plants; and (d) animal wastes are recycled and used for food, fertilizer and fuel. This strategy is particularly suitable for the conditions in (i) tropical countries, whose climate favours high crop/biomass yields per unit area and ease of fermentation of organic wastes, and (ii) family farms, for which diversification means greater opportunity for self-sufficiency and increased possibilities for use of family resources. (author)

  5. Nitrogen mineralization and denitrification as influenced by crop residue particle size

    DEFF Research Database (Denmark)

    Ambus, P.; Jensen, E.S.

    1997-01-01

    1: N-15-labelled ground (less than or equal to 3 mm) and cut (25 mm) barley residue, and microcrystalline cellulose+glucose were mixed into a sandy loam soil with additional inorganic N. Experiment 2: inorganic N-15 and C2H2 were added to soils with barley and pea material after 3, 26, and 109 days......Managing the crop residue particle size has the potential to affect N conservation in agricultural systems. We investigated the influence of barley (Hordeum vulgare) and pea (Pisum sativum) crop residue particle size on N mineralization and denitrification in two laboratory experiments. Experiment...... for measuring gross N mineralization and denitrification. Net N immobilization over 60 days in Experiment 1 cumulated to 63 mg N kg(-1) soil (ground barley), 42 (cut barley), and 122 (cellulose+glucose). More N was seemingly net mineralized from ground barley (3.3 mg N kg(-1) soil) than from cut barley (2.7 mg...

  6. Determine metrics and set targets for soil quality on agriculture residue and energy crop pathways

    Energy Technology Data Exchange (ETDEWEB)

    Ian Bonner; David Muth

    2013-09-01

    There are three objectives for this project: 1) support OBP in meeting MYPP stated performance goals for the Sustainability Platform, 2) develop integrated feedstock production system designs that increase total productivity of the land, decrease delivered feedstock cost to the conversion facilities, and increase environmental performance of the production system, and 3) deliver to the bioenergy community robust datasets and flexible analysis tools for establishing sustainable and viable use of agricultural residues and dedicated energy crops. The key project outcome to date has been the development and deployment of a sustainable agricultural residue removal decision support framework. The modeling framework has been used to produce a revised national assessment of sustainable residue removal potential. The national assessment datasets are being used to update national resource assessment supply curves using POLYSIS. The residue removal modeling framework has also been enhanced to support high fidelity sub-field scale sustainable removal analyses. The framework has been deployed through a web application and a mobile application. The mobile application is being used extensively in the field with industry, research, and USDA NRCS partners to support and validate sustainable residue removal decisions. The results detailed in this report have set targets for increasing soil sustainability by focusing on primary soil quality indicators (total organic carbon and erosion) in two agricultural residue management pathways and a dedicated energy crop pathway. The two residue pathway targets were set to, 1) increase residue removal by 50% while maintaining soil quality, and 2) increase soil quality by 5% as measured by Soil Management Assessment Framework indicators. The energy crop pathway was set to increase soil quality by 10% using these same indicators. To demonstrate the feasibility and impact of each of these targets, seven case studies spanning the US are presented

  7. Air Toxics Emissions from Open Burning of Crop Residues in Southeast Asia

    Science.gov (United States)

    KIM Oanh, N. T.; Permadi, D. A.; Hopke, P. K.; Smith, K. R.; Nguyet, D. A.

    2016-12-01

    Agricultural crops production in Southeast Asia (SEA) increases annually to meet domestic consumption of growing population and also for export. Crop residue open burning (CROB) is commonly practiced by farmers to quickly dispose of huge amounts of the agricultural waste, such as rice straw, generated after each crop cycle. This CROB activity emits various toxic air pollutants as well as short-lived climate pollutants such as black carbon particles. Our study focused on quantifying the 2015 annual emissions of semi-volatile organic compounds including polycyclic aromatic hydrocarbons (PAHs), dioxins/furans (PCDD/PCDF), organochlorine pesticides (OCP), along with other conventional trace gases, particulate matter, and greenhouse gases from CROB in 10 major agricultural crop producing SEA countries. Crop production statistics and current field OB practices were gathered from our primary surveys and relevant secondary data sources. Emission factors for rice straw and maize residue burning were taken mainly from our measurements in Thailand while for other crops relevant published data were used. The best emission estimates of air toxics from CROB in SEA were 112 g-TEQ/yr of PCDD/PCDF, 33 t/yr of OCP, and 25 Gg/yr of total PAH of which the well-known carcinogenic benzo[a]pyrene was 0.3 Gg/yr. The CROB of rice production had the highest shares of emissions (33-95%) among considered 8 crop types. Indonesia was the top contributor to the total SEA emissions (30-45%) followed by Vietnam (16-26%), Thailand (6-22%) and Myanmar (5-18%). The spatial distributions of emissions, 0.1º x 0.1º, for each specie were prepared using MODIS land cover data. Temporally, higher emissions were observed in the harvesting months of the main rice crops. This emissions database can be used in regional air quality modeling studies to assess the impacts of CROB activity and to promote non-open burning alternatives.

  8. Pesticide residues determination in Polish organic crops in 2007-2010 applying gas chromatography-tandem quadrupole mass spectrometry.

    Science.gov (United States)

    Walorczyk, Stanisław; Drożdżyński, Dariusz; Kowalska, Jolanta; Remlein-Starosta, Dorota; Ziółkowski, Andrzej; Przewoźniak, Monika; Gnusowski, Bogusław

    2013-08-15

    A sensitive, accurate and reliable multiresidue method based on the application of gas chromatography-tandem quadrupole mass spectrometry (GC-QqQ-MS/MS) has been established for screening, identification and quantification of a large number of pesticide residues in produce. The method was accredited in compliance with PN-EN ISO/IEC 17025:2005 standard and it was operated under flexible scope as PB-11 method. The flexible scope of accreditation allowed for minor modifications and extension of the analytical scope while using the same analytical technique. During the years 2007-2010, the method was used for the purpose of verification of organic crop production by multiresidue analysis for the presence of pesticides. A total of 528 samples of differing matrices such as fruits, vegetables, cereals, plant leaves and other green parts were analysed, of which 4.4% samples contained pesticide residues above the threshold value of 0.01 mg/kg. A total of 20 different pesticide residues were determined in the samples. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Potential soil quality impact of harvesting crop residues for bio fuels

    International Nuclear Information System (INIS)

    Karlen, D.

    2011-01-01

    We are in one of the greatest technological, environmental and social transitions since the industrial revolution, as we strive to replace fossil energy with renewable biomass resources. My objectives are to (1) briefly review increased public interest in harvesting crop residues as feedstock for bio energy, (2) discuss the work soil scientists must do to address those interests, and (3) examine how soil quality assessment can be used to help quantify soil biological, chemical and physical response to this transition. Rising global energy demand, dependence on unstable imports, volatility in price, and increasing public concern regarding fossil fuel combustion effects on global climate change are among the factors leading to an increased interest in development and use of renewable biomass sources for energy production. Although controlling soil erosion by wind and water is no less important than in the past, it is not the only factor that needs to be considered when evaluating the sustain ability of land management practices including harvest of crop residues as bio energy feedstock. The concept of soil quality assessment is reviewed and the Soil Management Assessment Framework (SMAF) is used to illustrate how such assessments can be used for assessing impacts of harvesting crop residue as feedstock for bio energy production. Preliminary results of the SMAF assessment show that soil organic carbon (SOC) is one of the lower scoring indicators and therefore needs to be monitored closely. Innovative soil and crop management strategies, including a landscape vision are offered as ideas for achieving sustainable food, feed, fiber, and energy production

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

    Directory of Open Access Journals (Sweden)

    Laura Agneessens

    2014-12-01

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

  11. Determination of crop residues and the physical and mechanical properties of soil in different tillage systems

    Directory of Open Access Journals (Sweden)

    P Ahmadi Moghaddam

    2016-04-01

    Full Text Available Introduction: Monitoring and management of soil quality is crucial for sustaining soil function in ecosystem. Tillage is one of the management operations that drastically affect soil physical quality. Conservation tillage methods are one of the efficient solutions in agriculture to reduce the soil erosion, air pollution, energy consumption, and the costs, if there is a proper management on the crop residues. One of the serious problems in agriculture is soil erosion which is rapidly increased in the recent decades as the intensity of tillage increases. This phenomenon occurs more in sloping lands or in the fields which are lacking from crop residues and organic materials. The conservation tillage has an important role in minimizing soil erosion and developing the quality of soil. Hence, it has attracted the attention of more researchers and farmers in the recent years. Materials and Methods: In this study, the effect of different tillage methods has been investigated on the crop residues, mechanical resistance of soil, and the stability of aggregates. This research was performed on the agricultural fields of Urmia University, located in Nazloo zone in 2012. Wheat and barley were planted in these fields, consecutively. The soil texture of these fields was loamy clay and the factorial experiments were done in a completely randomized block design. In this study, effect of three tillage systems including tillage with moldboard (conventional tillage, tillage with disk plow (reduced tillage, chisel plow (minimum tillage and control treatment on some soil physical properties was investigated. Depth is second factor that was investigated in three levels including 0-60, 60-140, and 140-200 mm. Moreover, the effect of different percentages of crop residues on the rolling resistance of non-driving wheels was studied in a soil bin. The contents of crop residues have been measured by using the linear transects and image processing methods. In the linear

  12. Determination of pesticide residue transfer rates (percent) from dried tea leaves to brewed tea.

    Science.gov (United States)

    Wang, Jian; Cheung, Wendy; Leung, Daniel

    2014-01-29

    This paper presents a study on pesticide residue transfer rates (%) from dried tea leaves to brewed tea. In the study, a brewing procedure simulated the preparation of a hot tea drink as in routine. After brewing, pesticide residues were extracted from brewed tea using a method known as QuEChERS (quick, easy, cheap, effective, rugged, and safe). An UHPLC/ESI-MS/MS method was developed and validated to identify and quantify up to 172 pesticides in both tea leaves and brewed tea samples. Quantification was achieved using matrix-matched standard calibration curves with isotopically labeled standards or a chemical analogue as internal standards, and the calibration curves consisted of six points (0.4, 2.0, 8.0, 16.0, 24.0, and 40.0 μg/L equivalent in sample). The method was validated at four concentration levels (4.0, 12, 20.0, and 32.0 μg/L equivalent in sample) using five different brewed tea matrices on two separate days per matrix. Method performance parameters included overall recovery, intermediate precision, and measurement uncertainty, which were evaluated according to a nested experimental design. Approximately, 95% of the pesticides studied had recoveries between 81 and 110%, intermediate precision ≤20%, and measurement uncertainty ≤40%. From a pilot study of 44 incurred tea samples, pesticide residues were examined for their ability to transfer from dried tea leaves to brewed tea. Each sample, both tea leaves and brewed tea, was analyzed in duplicate. Pesticides were found to have different transfer rates (%). For example, imidacloprid, methomyl, and carbendazim had transfer rates of 84.9, 83.4, and 92.4%, respectively.

  13. Effect of Cover Crop Residues on Some Physicochemical Properties of Soil and Emergence Rate of Potato

    OpenAIRE

    M. Ghaffari; G. Ahmadvand; M.R. Ardakani; M.R. Mosaddeghi; F. Yeganehehpoor; M. Gaffari; M. Mirakhori

    2012-01-01

    The aim of this study, was to evaluate the effect of winter cover crop residues on speed of seed  potato emergence and percentage of organic carbon, soil specific weight and soil temperature. An experiment was carried out at the Research Farm of Agriculture Faculty, Bu-AliSinaUniversity, in 2008-2009. The experiment was a randomized complete block design with three replications. Winter cover crops consisted of rye, barley and oilseed rape, each one with common plant density (rye and barley at...

  14. Safe apples for baby-food production: survey of pesticide treatment regimes leaving minimum residues.

    Science.gov (United States)

    Ticha, Jana; Hajslova, Jana; Kovalczuk, Tomas; Jech, Martin; Honzicek, Jiri; Kocourek, Vladimir; Lansky, Miroslav; Kloutvorova, Jana; Falta, Vladan

    2007-06-01

    A total of 19 pesticide preparations were used according to agricultural practice in six trials in apple orchards. Using gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS), premature Golden Delicious apples collected 64, 50, 36 days before harvest and mature fruit were examined for residues of active ingredients. No residues of triflumuron, triazamate, chlorpyrifos, etofenprox, fenoxycarb, kresoxim-methyl, cyprodinyl, difenoconazole or thiram were detected in the first sampling. Also, the levels of chlorpyrifos-methyl, penconazole, tebuconazole and tolylfluanid dropped during the pre-harvest interval. Detectable residues of pyridaben, thiacloprid, trifloxystrobin and tetraconazole in harvested fruits were below 0.01 mg kg(-1), which is the maximum concentration of residues acceptable by baby-food producers in any raw material. The only residues exceeding this concentration were captan and teflubenzuron. Based on the data, farmers can choose pesticides for optimal treatment of plants, while enabling growth of a safe crop suitable for baby-food production.

  15. Greenhouse crop residues: Energy potential and models for the prediction of their higher heating value

    Energy Technology Data Exchange (ETDEWEB)

    Callejon-Ferre, A.J.; Lopez-Martinez, J.A.; Manzano-Agugliaro, F. [Departamento de Ingenieria Rural, Universidad de Almeria, Ctra. Sacramento s/n, La Canada de San Urbano, 04120 Almeria (Spain); Velazquez-Marti, B. [Departamento de Ingenieria Rural y Agroalimentaria, Universidad Politecnica de Valencia, Camino de Vera s/n, 46022 Valencia (Spain)

    2011-02-15

    Almeria, in southeastern Spain, generates some 1,086,261 t year{sup -1} (fresh weight) of greenhouse crop (Cucurbita pepo L., Cucumis sativus L., Solanum melongena L., Solanum lycopersicum L., Phaseoulus vulgaris L., Capsicum annuum L., Citrillus vulgaris Schrad. and Cucumis melo L.) residues. The energy potential of this biomass is unclear. The aim of the present work was to accurately quantify this variable, differentiating between crop species while taking into consideration the area they each occupy. This, however, required the direct analysis of the higher heating value (HHV) of these residues, involving very expensive and therefore not commonly available equipment. Thus, a further aim was to develop models for predicting the HHV of these residues, taking into account variables measured by elemental and/or proximate analysis, thus providing an economically attractive alternative to direct analysis. All the analyses in this work involved the use of worldwide-recognised standards and methods. The total energy potential for these plant residues, as determined by direct analysis, was 1,003,497.49 MW h year{sup -1}. Twenty univariate and multivariate equations were developed to predict the HHV. The R{sup 2} and adjusted R{sup 2} values obtained for the univariate and multivariate models were 0.909 and 0.946 or above respectively. In all cases, the mean absolute percentage error varied between 0.344 and 2.533. These results show that any of these 20 equations could be used to accurately predict the HHV of crop residues. The residues produced by the Almeria greenhouse industry would appear to be an interesting source of renewable energy. (author)

  16. Variations in thematic mapper spectra of soil related to tillage and crop residue management - Initial evaluation

    Science.gov (United States)

    Seeley, M. W.; Ruschy, D. L.; Linden, D. R.

    1983-01-01

    A cooperative research project was initiated in 1982 to study differences in thematic mapper spectral characteristics caused by variable tillage and crop residue practices. Initial evaluations of radiometric data suggest that spectral separability of variably tilled soils can be confounded by moisture and weathering effects. Separability of bare tilled soils from those with significant amounts of corn residue is enhanced by wet conditions, but still possible under dry conditions when recent tillage operations have occurred. In addition, thematic mapper data may provide an alternative method to study the radiant energy balance at the soil surface in conjunction with variable tillage systems.

  17. Concentrations of imidacloprid and thiamethoxam in pollen, nectar and leaves from seed-dressed cotton crops and their potential risk to honeybees (Apis mellifera L.).

    Science.gov (United States)

    Jiang, Jiangong; Ma, Dicheng; Zou, Nan; Yu, Xin; Zhang, Zhengqun; Liu, Feng; Mu, Wei

    2018-06-01

    Neonicotinoid insecticides (NIs) have recently been recognized as co-factors in the decline of honeybee colonies because most neonicotinoids are systemic and can transfer into the pollen and nectar of many pollinated crops. In this study, we collected pollen, nectar and leaves from a cotton crop treated with imidacloprid and thiamethoxam to measure the residue levels of these two NIs at different application doses during the flowering period. Then, the residual data were used to assess the risk posed by the systemic insecticides to honeybees following mandated methods published by the European Food Safety Authority (EFSA), and a highly toxic risk to honeybees was highlighted. Imidacloprid was found in both pollen and nectar samples, whereas thiamethoxam was found in 90% of pollen samples and over 60% of nectar samples. Analysis of the pollen and nectar revealed residual amounts of imidacloprid ranging from 1.61 to 64.58 ng g -1 in the pollen and from not detected (ND) to 1.769 ng g -1 in the nectar. By comparison, the thiamethoxam concentrations in pollen and nectar ranged from ND to 14.521 ng g -1 and from ND to 4.285 ng g -1 , respectively. The results of this study provide information on the transfer of two NIs from seed treatment to areas of the plant and provides an understanding of the potential exposure of the bee and other pollinators to systemic insecticides. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Effect of Cover Crop Residues on Some Physicochemical Properties of Soil and Emergence Rate of Potato

    Directory of Open Access Journals (Sweden)

    M. Ghaffari

    2012-07-01

    Full Text Available The aim of this study, was to evaluate the effect of winter cover crop residues on speed of seed  potato emergence and percentage of organic carbon, soil specific weight and soil temperature. An experiment was carried out at the Research Farm of Agriculture Faculty, Bu-AliSinaUniversity, in 2008-2009. The experiment was a randomized complete block design with three replications. Winter cover crops consisted of rye, barley and oilseed rape, each one with common plant density (rye and barley at 190 kg.ha-1 and oilseed rape at 9 kg.ha-1 and triple plant densities(rye and barley 570 kg.ha-1 and oilseed rape, 27 kg.ha-1 and control (without cover crop. The results showed that rye and barley with triple plant densities produced higher biomass (1503.5 and 1392.2 g/m2, respectively than other treatments.Soil physicochemical properties were affected significantly by using cover crops. Rye, barley, and oilseed rape with triple rate and rye with common rape of plant densities produced, the highest organic carbon. Green manure of rye and barley with triple and rye with common rate plant densities, reduced soil specific weights by 17.3, 18 and 18 percent as compared with the control treatment (without cover crop planting. Rye and barley with triple plant densities increased average soil temperature by 12 and 11 percent respectively in comparison with control treatment. These treatments increased speed of seed potato emergence by 20 and 12 percent respectively as compared with that of control treatment, respectively. Other treatments showed no significant difference as compared to control. Cover crop residues increased plants speed of seed potato emergence through improving soil conditions.

  19. Phosphorus management and its utilization by berseem (Trifolium alexandrinum L.) and residual effect on forage crops

    International Nuclear Information System (INIS)

    Sinha, M.N.; Rai, R.K.

    1990-01-01

    Placement of phosphorus even to a broadcast sown crop like berseem helped in boosting up 10 per cent higher forage production over the conventional practice of broadcast application of phosphatic fertilizer without altering the normal practice of sowing broadcast. Likewise, P from fertilizer source and its utilization by the crop increased substantially and were higher in favour of placement of P. Closer the rows of phosphorus placement, greater was the recovery of applied P. The yield of forage increased with the increase in the level of P ranging from 75 to 225 kg P 2 O 5 /ha and the optimum dose was 173 kg P 2 O 5 /ha while the utilization of P decreased with increase in levels. There was enormous response to residual P after berseem and the residual forage yield increased with increase in P levels. A fertilized cereal crop after berseem was in no way better than unfertilized crop after berseem from productivity point of view. (author). 11 refs., 5 tabs

  20. Modeling Emissions and Vertical Plume Transport of Crop Residue Burning Experiments in the Pacific Northwest

    Science.gov (United States)

    Zhou, L.; Baker, K. R.; Napelenok, S. L.; Pouliot, G.; Elleman, R. A.; ONeill, S. M.; Urbanski, S. P.; Wong, D. C.

    2017-12-01

    Crop residue burning has long been a common practice in agriculture with the smoke emissions from the burning linked to negative health impacts. A field study in eastern Washington and northern Idaho in August 2013 consisted of multiple burns of well characterized fuels with nearby surface and aerial measurements including trace species concentrations, plume rise height and boundary layer structure. The chemical transport model CMAQ (Community Multiscale Air Quality Model) was used to assess the fire emissions and subsequent vertical plume transport. The study first compared assumptions made by the 2014 National Emission Inventory approach for crop residue burning with the fuel and emissions information obtained from the field study and then investigated the sensitivity of modeled carbon monoxide (CO) and PM2.5 concentrations to these different emission estimates and plume rise treatment with CMAQ. The study suggests that improvements to the current parameterizations are needed in order for CMAQ to reliably reproduce smoke plumes from burning. In addition, there is enough variability in the smoke emissions, stemming from variable field-specific information such as field size, that attempts to model crop residue burning should use field-specific information whenever possible.

  1. Fate of glyphosate and degradates in cover crop residues and underlying soil: A laboratory study

    International Nuclear Information System (INIS)

    Cassigneul, A.; Benoit, P.; Bergheaud, V.; Dumeny, V.; Etiévant, V.; Goubard, Y.; Maylin, A.; Justes, E.; Alletto, L.

    2016-01-01

    The increasing use of cover crops (CC) may lead to an increase in glyphosate application for their destruction. Sorption and degradation of "1"4C-glyphosate on and within 4 decaying CC-amended soils were compared to its fate in a bare soil. "1"4C-Glyphosate and its metabolites distribution between mineralized, water-soluble, NH_4OH-soluble and non-extractable fractions was determined at 5 dates during a 20 °C/84-d period. The presence of CC extends "1"4C-glyphosate degradation half-life from 7 to 28 days depending on the CC. "1"4C-Glyphosate dissipation occurred mainly through mineralization in soils and through mineralization and bound residue formation in decaying CC. Differences in sorption and degradation levels were attributed to differences in composition and availability to microorganisms. CC- and soil-specific dissipation patterns were established with the help of explicit relationships between extractability and microbial activity. - Highlights: • Glyphosate sorption on cover crop residues increases with their decomposition degree. • Glyphosate degradation and mineralization are lower in mulch than in soil. • Nonextractable residue formation is one of the main dissipation pathways of glyphosate in cover crop mulch.

  2. Fate of glyphosate and degradates in cover crop residues and underlying soil: A laboratory study

    Energy Technology Data Exchange (ETDEWEB)

    Cassigneul, A. [Université de Toulouse — École d' ingénieurs de Purpan, UMR 1248 AGIR — 75, Voie du TOEC BP 57 611, 31 076, Toulouse cedex 3 (France); INRA, UMR 1402 ECOSYS, 78850 Thiverval-Grignon (France); Benoit, P.; Bergheaud, V.; Dumeny, V.; Etiévant, V. [INRA, UMR 1402 ECOSYS, 78850 Thiverval-Grignon (France); Goubard, Y. [AgroParisTech, UMR 1402 ECOSYS, 78850 Thiverval-Grignon (France); Maylin, A. [Université de Toulouse — École d' ingénieurs de Purpan, UMR 1248 AGIR — 75, Voie du TOEC BP 57 611, 31 076, Toulouse cedex 3 (France); Justes, E. [INRA, UMR 1248 AGIR Auzeville — BP 52 627, 31 326, Castanet-Tolosan cedex (France); Alletto, L. [Université de Toulouse — École d' ingénieurs de Purpan, UMR 1248 AGIR — 75, Voie du TOEC BP 57 611, 31 076, Toulouse cedex 3 (France)

    2016-03-01

    The increasing use of cover crops (CC) may lead to an increase in glyphosate application for their destruction. Sorption and degradation of {sup 14}C-glyphosate on and within 4 decaying CC-amended soils were compared to its fate in a bare soil. {sup 14}C-Glyphosate and its metabolites distribution between mineralized, water-soluble, NH{sub 4}OH-soluble and non-extractable fractions was determined at 5 dates during a 20 °C/84-d period. The presence of CC extends {sup 14}C-glyphosate degradation half-life from 7 to 28 days depending on the CC. {sup 14}C-Glyphosate dissipation occurred mainly through mineralization in soils and through mineralization and bound residue formation in decaying CC. Differences in sorption and degradation levels were attributed to differences in composition and availability to microorganisms. CC- and soil-specific dissipation patterns were established with the help of explicit relationships between extractability and microbial activity. - Highlights: • Glyphosate sorption on cover crop residues increases with their decomposition degree. • Glyphosate degradation and mineralization are lower in mulch than in soil. • Nonextractable residue formation is one of the main dissipation pathways of glyphosate in cover crop mulch.

  3. Nitrogen-to-Protein Conversion Factors for Crop Residues and Animal Manure Common in China.

    Science.gov (United States)

    Chen, Xueli; Zhao, Guanglu; Zhang, Yang; Han, Lujia; Xiao, Weihua

    2017-10-25

    Accurately determining protein content is essential in exploiting biomass as feed and fuel. A survey of biomass samples in China indicated protein contents from 2.65 to 3.98% for crop residues and from 6.07 to 10.24% for animal manure of dry basis. Conversion factors based on amino acid nitrogen (k A ) ranged from 5.42 to 6.00 for the former and from 4.78 to 5.36 for the latter, indicating that the traditional factor of 6.25 is not suitable for biomass samples. On the other hand, conversion factors from Kjeldahl nitrogen (k P ) ranged from 3.97 to 4.57 and from 2.76 to 4.31 for crop residues and animal manure, respectively. Of note, conversion factors were strongly affected by amino acid composition and levels of nonprotein nitrogen. Thus, k P values of 4.23 for crop residues, 4.11 for livestock manure, and 3.11 for poultry manure are recommended to better estimate protein content from total nitrogen.

  4. An investigation of radionuclide uptake into food crops grown in soils treated with bauxite mining residues

    International Nuclear Information System (INIS)

    Cooper, M.B.; Clarke, P.C.; Robertson, W.; McPharlin, I.R.; Jeffrey, R.C.

    1994-01-01

    Sandy soils of the coastal plain area of Western Australia have poor phosphorous retention capacity which leads to pollution of surface water bodies in the region. Application of bauxite mining residues (termed 'red mud') to vegetable and crops has been proposed as a solution to increase the phosphorous and water retention and thereby reduce the leaching of nutrients. The thorium and radium-226 concentrations in the 'red mud' residues are in excess of 1 kBq/kg, and 300 Bq/kg respectively. Potentially, the use of these residues on agricultural land could result in increased levels of radionuclides in food grown in amended soils. The transfer of long-lived radionuclides of both the natural thorium and uranium series to a variety of vegetable crops grown under controlled conditions is investigated. The effects of varying the rates of application of 'red mud' and phosphate fertilizers on radionuclide uptake are studied. It has been shown previously that fallout caesium-137 is sandy soils of the region transfers readily to food and grazing crops. Some of the parameters which influence that transfer are also examined. (author). 14 refs., 1 fig., 8 tabs

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

    International Nuclear Information System (INIS)

    Cherubini, Francesco; Ulgiati, Sergio

    2010-01-01

    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 N 2 O 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 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

  6. Tillage and residue management effect on soil properties, crop performance and energy relations in greengram (Vigna radiata L. under maize-based cropping systems

    Directory of Open Access Journals (Sweden)

    J.R. Meena

    2015-12-01

    Full Text Available Effect of tillage and crop residue management on soil properties, crop performance, energy relations and economics in greengram (Vigna radiata L. was evaluated under four maize-based cropping systems in an Inceptisol of Delhi, India. Soil bulk density, hydraulic conductivity and aggregation at 0–15 cm layer were significantly affected both by tillage and cropping systems, while zero tillage significantly increased the soil organic carbon content. Yields of greengram were significantly higher in maize–chickpea and maize–mustard systems, more so with residue addition. When no residue was added, conventional tillage required 20% higher energy inputs than the zero tillage, while the residue addition increased the energy output in both tillage practices. Maize–wheat–greengram cropping system involved the maximum energy requirement and the cost of production. However, the largest net return was obtained from the maize–chickpea–greengram system under the conventional tillage with residue incorporation. Although zero tillage resulted in better aggregation, C content and N availability in soil, and reduced the energy inputs, cultivation of summer greengram appeared to be profitable under conventional tillage system with residue incorporation.

  7. Methods to enhance hydrolysis during one and two-stage anaerobic digestion of energy crops and crop residues

    Energy Technology Data Exchange (ETDEWEB)

    Jagadabhi, P. S.

    2011-07-01

    The objective of this thesis was to evaluate methods to enhance hydrolysis (measured as specific SCOD production, g SCOD g-1 VS) during one and two-stage anaerobic digestion (AD) of energy crops and crop residues. Addition of macro (NH{sub 4}Cl), micro nutrients (Fe, Ni, Co and Mo) and leachate replacement during mono-digestion of grass silage in one-stage leach bed reactors (LBRs) enhanced hydrolysis by 18 % (0.56 g SCOD g-1 VS), 7 % (0.45 g SCOD g-1 VS) and 34 % (0.51 g SCOD g-1 VS) respectively compared to respective controls. On the other hand, creating micro-aerobic conditions (at 1 l min-1, 2.5 l of air) did not improve hydrolysis but enhanced VFA production by 4 fold (from 2.2 g l-1 to 9 g l-1). Application of rumen cultures improved hydrolysis by 10 % (0.33 g SCOD g-1 VS) more than control (0.30 g SCOD g-1 VS). Similarly, during two-stage AD in LBR-UASB reactor configuration leachate replacement enhanced hydrolysis in cucumber and grass silage (0.5 g SCOD g-1 VS) than in tomato and common reed (0.35 and 0.15 g SCOD g-1 VS respectively). During co-digestion of grass silage and cow manure at a ratio of 30:70 (VS) in CSTR, re-circulation of alkali treated solid fraction of digestate did not improve the anaerobic biodegradation rates or methane yields. Results from batch experiments showed that methane potential of grass silage varied from 0.28-0.39 m3 CH{sub 4} kg-1 VS{sub added} in all the experiments. On the other hand, methane potentials of the studied crop residues were 0.32 m3 CH{sub 4} kg-1 VS{sub added} for tomato and 0.26 m3 CH{sub 4} kg-1 VS{sub added} for cucumber and common reed. Alkali pretreatment of solids, obtained from digestate (during co-digestion of grass silage and cow manure in one-stage CSTRs), at a low concentration of 20 g NaOH kg-1 VS resulted in higher methane yield (0.34 m3 CH{sub 4} kg-1 VS{sub added}) than the other tested dosages (40 and 60 g NaOH kg-1 VS). Addition of macro nutrient (NH{sub 4}Cl) enhanced methane potential of

  8. The crop-residue of fiber hemp cv. Futura 75: from a waste product to a source of botanical insecticides.

    Science.gov (United States)

    Benelli, Giovanni; Pavela, Roman; Lupidi, Giulio; Nabissi, Massimo; Petrelli, Riccardo; Ngahang Kamte, Stephane L; Cappellacci, Loredana; Fiorini, Dennis; Sut, Stefania; Dall'Acqua, Stefano; Maggi, Filippo

    2018-04-01

    In the attempt to exploit the potential of the monoecious fiber hemp cv. Futura 75 in new fields besides textile, cosmetics and food industry, its crop-residue given by leaves and inflorescences was subjected to hydrodistillation to obtain the essential oils. These are niche products representing an ideal candidate for the development of natural insecticides for the control and management of mosquito vectors, houseflies and moth pests. After GC-MS analysis highlighting a safe and legal chemical profile (THC in the range 0.004-0.012% dw), the leaf and inflorescence essential oils were investigated for the insecticidal potential against three insect targets: the larvae of Culex quinquefasciatus and Spodoptera littoralis and the adults of Musca domestica. The essential oil from inflorescences, showing (E)-caryophyllene (21.4%), myrcene (11.3%), cannabidiol (CBD, 11.1%), α-pinene (7.8%), terpinolene (7.6%), and α-humulene (7.1%) as the main components, was more effective than leaf oil against these insects, with LD 50 values of 65.8 μg/larva on S. littoralis, 122.1 μg/adult on M. domestica, and LC 50 of 124.5 μl/l on C. quinquefasciatus larvae. The hemp essential oil moderately inhibited the acetylcholinesterase (AChE), which is a target enzyme in pesticide science. Overall, these results shed light on the future application of fiber hemp crop-residue for the development of effective, eco-friendly and sustainable insecticides.

  9. An Image Segmentation Based on a Genetic Algorithm for Determining Soil Coverage by Crop Residues

    Science.gov (United States)

    Ribeiro, Angela; Ranz, Juan; Burgos-Artizzu, Xavier P.; Pajares, Gonzalo; Sanchez del Arco, Maria J.; Navarrete, Luis

    2011-01-01

    Determination of the soil coverage by crop residues after ploughing is a fundamental element of Conservation Agriculture. This paper presents the application of genetic algorithms employed during the fine tuning of the segmentation process of a digital image with the aim of automatically quantifying the residue coverage. In other words, the objective is to achieve a segmentation that would permit the discrimination of the texture of the residue so that the output of the segmentation process is a binary image in which residue zones are isolated from the rest. The RGB images used come from a sample of images in which sections of terrain were photographed with a conventional camera positioned in zenith orientation atop a tripod. The images were taken outdoors under uncontrolled lighting conditions. Up to 92% similarity was achieved between the images obtained by the segmentation process proposed in this paper and the templates made by an elaborate manual tracing process. In addition to the proposed segmentation procedure and the fine tuning procedure that was developed, a global quantification of the soil coverage by residues for the sampled area was achieved that differed by only 0.85% from the quantification obtained using template images. Moreover, the proposed method does not depend on the type of residue present in the image. The study was conducted at the experimental farm “El Encín” in Alcalá de Henares (Madrid, Spain). PMID:22163966

  10. Fundamental and molecular composition characteristics of biochars produced from sugarcane and rice crop residues and by-products.

    Science.gov (United States)

    Jeong, Chang Yoon; Dodla, Syam K; Wang, Jim J

    2016-01-01

    Biochar conversion of sugarcane and rice harvest residues provides an alternative for managing these crop residues that are traditionally burned in open field. Sugarcane leaves, bagasse, rice straw and husk were converted to biochar at four pyrolysis temperatures (PTs) of 450 °C, 550 °C, 650 °C, and 750 °C and evaluated for various elemental, molecular and surface properties. The carbon content of biochars was highest for those produced at 650-750 °C. Biochars produced at 550 °C showed the characteristics of biochar that are commonly interpreted as being stable in soil, with low H/C and O/C ratios and pyrolysis fingerprints dominated by aromatic and polyaromatic hydrocarbons. At 550 °C, all biochars also exhibited maximum CEC values with sugarcane leaves biochar (SLB) > sugarcane bagasse biochar (SBB) > rice straw biochar (RSB) > rice husk biochar (RHB). The pore size distribution of biochars was dominated by pores of 20 nm and high PT increased both smaller and larger than 50 nm pores. Water holding capacity of biochars increased with PT but the magnitude of the increase was limited by feedstock types, likely related to the hydrophobicity of biochars as evident by molecular composition, besides pore volume properties of biochars. Py-GC/MS analysis revealed a clear destruction of lignin with decarboxylation and demethoxylation at 450 °C and dehydroxylation at above 550 °C. Overall, biochar molecular compositions became similar as PT increased, and the biochars produced at 550 °C demonstrated characteristics that have potential benefit as soil amendment for improving both C sequestration and nutrient dynamics. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Activity and Residual Effect of Two Formulations of Lambdacyhalothrin Sprayed on Palm Leaves to Rhodnius prolixus

    Directory of Open Access Journals (Sweden)

    Mazariego-Arana Miguel Angel

    2002-01-01

    Full Text Available The insecticidal activity and residual effect of two formulations of lambdacyhalothrin were evaluated with Rhodnius prolixus;laboratory and field tests were conducted in the State of Chiapas, Mexico. The results indicate that the lethal concentrations of the active ingredient of SC (LC50 = 2.37 and LC90 = 8.5 mg, a.i./m² were 4-8 times than those with the insecticide WP applied on R. prolixus bugs in palm leaves, a common building material for thatched roofs. Other investigators in South America recommended applying 30 mg a.i./m² in porous materials; we obtained that the products WP and SC were 3.5 and 16 times more effective on palm leaves. Regarding the evaluation of the residual effects in field spraying, there was up to 15 months persistence after the application of WP in two doses (8.6 mg a.i./m² and 3.752 mg a.i./m² with SC. We consider R. prolixus highly susceptible to the employed pyrethroids; they could be used to control this vector in the state of Chiapas, Mexico.

  12. Impact of agriculture crop residue burning on atmospheric aerosol loading – a study over Punjab State, India

    Directory of Open Access Journals (Sweden)

    Darshan Singh

    2010-02-01

    Full Text Available The present study deals with the impact of agriculture crop residue burning on aerosol properties during October 2006 and 2007 over Punjab State, India using ground based measurements and multi-satellite data. Spectral aerosol optical depth (AOD and Ångström exponent (α values exhibited larger day to day variation during crop residue burning period. The monthly mean Ångström exponent "α" and turbidity parameter "β" values during October 2007 were 1.31±0.31 and 0.36±0.21, respectively. The higher values of "α" and "β" suggest turbid atmospheric conditions with increase in fine mode aerosols over the region during crop residue burning period. AURA-OMI derived Aerosol Index (AI and Nitrogen dioxide (NO2 showed higher values over the study region during October 2007 compared to October 2006 suggesting enhanced atmospheric pollution associated with agriculture crop residue burning.

  13. Development of the crop residue and rangeland burning in the 2014 National Emissions Inventory using information from multiple sources

    Data.gov (United States)

    U.S. Environmental Protection Agency — This workbook contains all the activity data, emission factor data, and ancillary data used to compute crop residue burning and rangeland emissions for the 2014 NEI...

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

    Directory of Open Access Journals (Sweden)

    Robert L De Haan

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

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

    Science.gov (United States)

    De Haan, Robert L; Schuiteman, Matthew A; Vos, Ronald J

    2017-01-01

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

  16. Morphology, composition, and mixing state of primary particles from combustion sources ? crop residue, wood, and solid waste

    OpenAIRE

    Liu, Lei; Kong, Shaofei; Zhang, Yinxiao; Wang, Yuanyuan; Xu, Liang; Yan, Qin; Lingaswamy, A. P.; Shi, Zongbo; Lv, Senlin; Niu, Hongya; Shao, Longyi; Hu, Min; Zhang, Daizhou; Chen, Jianmin; Zhang, Xiaoye

    2017-01-01

    Morphology, composition, and mixing state of individual particles emitted from crop residue, wood, and solid waste combustion in a residential stove were analyzed using transmission electron microscopy (TEM). Our study showed that particles from crop residue and apple wood combustion were mainly organic matter (OM) in smoldering phase, whereas soot-OM internally mixed with K in flaming phase. Wild grass combustion in flaming phase released some Cl-rich-OM/soot particles and cardboard combusti...

  17. The influence of nitrogen - urea fertilization to leaves and chloride chlorocholine on the accumulation Cs-137 in spring wheat crops

    International Nuclear Information System (INIS)

    Hrynczuk, B.; Weber, R.

    1998-01-01

    In pot experiments were studied effects of using nitrogen urea solution to leaves and use chloride chlorocholine on the Cs-137 accumulation in spring wheat crops. The Cs-137 contamination was conducted from soil and through leaves. It has been found that use nitrogen fertilization as urea solution spray and in addition use chloride chlorocholine caused an increase of Cs-137 concentration in grain from the contaminated soil. Accumulation of Cs-137 in spring wheat grain is 2-4 times higher coming from the contaminated leaves in blooming phase in comparison to the grain of plants contaminated in spread phase. The urea solution fertilization used on leaves and addition chloride chlorocholine did not influence the Cs-137 accumulation in grain when the plants were contaminated in the early growing phase. The Cs-137 contamination brought on the plants after using chloride chlorocholine in subsequent growing phases passed early into spring wheat grain. (author)

  18. Soil Temperature Moderation by Crop Residue Mulch, Grevilla Robusta Tillage Mode

    International Nuclear Information System (INIS)

    Oteng'i, S.B.B.

    2006-01-01

    The effects of mulching with crop residues and shading by Grevillea robust trees on the soil temperatures of Mt. Kenya Volcanic soils at Matanya area, Laikipia district, were studied. Soil thermistors connected to data-loggers(type Grant squirrel)were used to record soil temperaturs. The soils were mulched and minimum tilled (depths of 0.04 till 0.05m), and unmulched and deep tilled (depths 0.20till 0.25m) in plots of pruned and unpruned trees and also to cotrol (non-agroforestry) plots. The results showed that closer tp the trees, canopy differences ionfluenced changes in soil temperatures of about ≠2.0 degrees centrigrade. The dumping depth and Stigters ratio values showed soil temperatures were modified by treatment and tree canopy differences. The modified soil temperatures resulted in better crop performance when the soil water was adequate.(author)

  19. Herbicide-induced changes in 14CO2 uptake of leaves of some crop and weed species

    International Nuclear Information System (INIS)

    Santakumari, M.; Rama Das, V.S.

    1980-01-01

    The effect of diuron or atrazine on the rate of photosynthetic 14 CO 2 uptake of two each crop (Pisum Sativum and Pennisetum typhoides) and weed species (Amaranthus viridis and Cyperus rotundus) was studied. The results indicated a marked inhibition of 14 CO 2 fixation of leaves within two hours after diuron or atrazine treatment. However the resistant plants were able to exhibit a recovery of the net photosynthetic rate subsequently while the susceptible plants failed to recover. The results suggested that even with fully open stomata and available NADPH, the normal CO 2 fixation was not restored by herbicide treated leaves. (author)

  20. Cover Crop (Rye) and No-Till System in Wisconsin

    OpenAIRE

    Alföldi, Thomas

    2014-01-01

    Erin Silva, University of Wisconsin, describes an organic no-till production technique using rye as cover crop to suppress weeds in the following production season. Using a roller-crimper, the overwintering rye is terminated at the time of cash crop planting, leaving a thick mat of plant residue on the soil surface. Soybeans are sown directly into the cover crop residue, allowing the cash crop to emerge through the terminated cover crop while suppressing weeds throughout the season. W...

  1. Using a decision support system to optimize production of agricultural crop residue Biofeedstock

    International Nuclear Information System (INIS)

    Hoskinson, Reed L.; Rope, Ronald C.; Fink, Raymond K.

    2007-01-01

    For several years the Idaho National Laboratory (INL) has been developing a Decision Support System for Agriculture (DSS4Ag) which determines the economically optimum recipe of various fertilizers to apply at each site in a field to produce a crop, based on the existing soil fertility at each site, as well as historic production information and current prices of fertilizers and the forecast market price of the crop at harvest. In support of the growing interest in agricultural crop residues as a bioenergy feedstock, we have extended the capability of the DSS4Ag to develop a variable-rate fertilizer recipe for the simultaneous economically optimum production of both grain and straw. In this paper we report the results of 2 yr of field research testing and enhancing the DSS4Ag's ability to economically optimize the fertilization for the simultaneous production of both grain and its straw, where the straw is an agricultural crop residue that can be used as a biofeedstock. For both years, the DSS4Ag reduced the cost and amount of fertilizers used and increased grower profit, while reducing the biomass produced. The DSS4Ag results show that when a biorefinery infrastructure is in place and growers have a strong market for their straw it is not economically advantageous to increase fertilization in order to try to produce more straw. This suggests that other solutions, such as single-pass selective harvest, must be implemented to meet national goals for the amount of biomass that will be available for collection and use for bioenergy. (author)

  2. Effect of torrefaction conditions on greenhouse crop residue: Optimization of conditions to upgrade solid characteristics.

    Science.gov (United States)

    Iáñez-Rodríguez, Irene; Martín-Lara, María Ángeles; Blázquez, Gabriel; Pérez, Antonio; Calero, Mónica

    2017-11-01

    This work investigated the possibility of using a greenhouse crop waste as a fuel, since it is an abundant residue in the Mediterranean area of Spain. The residue is mainly composed by biomass with a little quantity of plastic. The physical and chemical characteristics of the biomass were determined by elemental analysis, proximate analysis, FT-IR, FE-SEM and thermogravimetry. Additionally, a torrefaction process was carried out as a pre-treatment to improve the energy properties of the biomass material. The optimal conditions (time and temperature) of torrefaction were found to be 263°C and 15min using the gain and loss method. Further studies were carried out with the sample prepared with the nearest conditions to the optimal in order to determine the effect of the plastic fraction in the characteristics and torrefaction process of the waste studied. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. MAIZE YIELD AND ITS STABILITY AS AFFECTED BY TILLAGE AND CROP RESIDUE MANAGEMENT IN THE EASTERN ROMANIAN DANUBE PLAIN

    Directory of Open Access Journals (Sweden)

    Alexandru COCIU

    2015-10-01

    Full Text Available Rainfed crop management systems need to be optimized to provide more resilient options in order to cope with projected climatic scenarios which are forecasting a decrease in mean precipitation and more frequent extreme drought periods in the Eastern Romanian Danube Plain. This research, carried out in the period of 2011-2014, had as main purpose the determination of influence of tillage practices and residue management on rainfall use efficiency, maize yield and its stability, in order to evaluate the advantages of conservation agriculture (CA in the time of stabilization of direct seeding effects, in comparison with traditional chisel tillage. The maize grain yields are presented for each crop management practices, as follows: (1 chisel tillage, retained crop residues being chopped and incorporated (ciz; (2 zero tillage, retained crop residue chopped and kept on the field in short flat condition (rvt; (3 zero tillage, crop residues kept on the field in short root-anchored condition (1/2rva, and (4 zero tillage, crop residues kept on the field in tall root-anchored condition (1/1rva. In 2012, a year with prolonged drought during vegetative growth, yield differences between zero tillage with short root-anchored residue retention (1/2rva and chisel tillage with residue incorporation (ciz were positive, up to 840 kg ha-1. In average over 2011-2014, conservation agriculture (CA practices had a yield advantage over traditional chisel tillage practice. Zero tillage with residue retention used rainfall more efficiently so suggesting that it is a more resilient agronomic system than traditional (conventional practices involving chisel tillage with residue incorporation.

  4. Quantum-Dot-Based Lateral Flow Immunoassay for Detection of Neonicotinoid Residues in Tea Leaves.

    Science.gov (United States)

    Wang, Shuangjie; Liu, Ying; Jiao, Shasha; Zhao, Ying; Guo, Yirong; Wang, Mengcen; Zhu, Guonian

    2017-11-22

    Neonicotinoid insecticides are commonly used for pest control on tea plantations as a result of their broad-spectrum activity. However, neonicotinoid residues released from tea leaves into tea infusions pose a dietary risk to consumers. Therefore, a rapid, sensitive, and reliable on-site detection method for neonicotinoids is needed. We developed a quantum-dot-based fluorescent lateral flow immunochromatographic strip (LFICS) combined with a broad-specific antibody for detection of typical neonicotinoids (imidacloprid, imidaclothiz, and clothianidin), with sensitivities [50% inhibitory concentration (IC 50 )] of 0.104-0.33 ng/mL and visual detection limits of 0.5-1 ng/mL. The strip assay could be completed in less than 30 min. Using the LFICS to analyze spiked tea samples (green tea, black tea, and oolong tea), the average recovery of the three neonicotinoids ranged between 71 and 111%, with the coefficient of variation below 12%. The results from the LFICS tests for field samples were consistent with results from ultraperformance liquid chromatography-tandem mass spectrometry. The newly developed strip is a useful tool for the on-site detection of neonicotinoid residues in tea.

  5. Composting of cow dung and crop residues using termite mounds as bulking agent.

    Science.gov (United States)

    Karak, Tanmoy; Sonar, Indira; Paul, Ranjit K; Das, Sampa; Boruah, R K; Dutta, Amrit K; Das, Dilip K

    2014-10-01

    The present study reports the suitability of termite mounds as a bulking agent for composting with crop residues and cow dung in pit method. Use of 50 kg termite mound with the crop residues (stover of ground nut: 361.65 kg; soybean: 354.59 kg; potato: 357.67 kg and mustard: 373.19 kg) and cow dung (84.90 kg) formed a good quality compost within 70 days of composting having nitrogen, phosphorus and potassium as 20.19, 3.78 and 32.77 g kg(-1) respectively with a bulk density of 0.85 g cm(-3). Other physico-chemical and germination parameters of the compost were within Indian standard, which had been confirmed by the application of multivariate analysis of variance and multivariate contrast analysis. Principal component analysis was applied in order to gain insight into the characteristic variables. Four composting treatments formed two different groups when hierarchical cluster analysis was applied. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Anaerobic biodegradability and methane potential of crop residue co-digested with buffalo dung

    International Nuclear Information System (INIS)

    Sahito, A.R.; Mahar, R.B.; Brohi, K.M.

    2013-01-01

    ABD (Anaerobic Biodegradability) and BMP (Biochemical Methane Potential) of banana plant waste, canola straw, cotton stalks, rice straw, sugarcane trash and wheat straw co-digested with buffalo dung was evaluated through AMPTS (Automatic Methane Potential Test System). The substrates were analyzed for moisture, TS (Total Solids) and VS (Volatile Solids), ultimate analysis (CHONS), pH and TA (Total Alkalinity). The BMP/sub observed/ during incubation of 30 days at the temperature of 37+-0.2+-degree C was 322 Nml CH4/g VSadd for wheat straw followed by 260, 170, 149, 142 and 138 Nml CH4/gVS/sub add/ for canola straw, rice straw, cotton stalks, banana plant waste and sugarcane trash respectively, whereas the maximum theoretical BMP was 481 Nml CH/sub 4//gVS/sub add/ for cotton stalks, followed by 473, 473, 446, 432 and 385 Nml CH/sub 4//gVS/sub add/ for wheat straw, banana plant waste, canola straw, rice straw and sugarcane trash respectively. The percentage ABD values were in the range of 68-30%. In addition to this, the effect of lignin content in the crop residue was evaluated on the ABD. The results of this study indicate that, the co-digestion of the crop residues with buffalo dung is feasible for production of renewable methane. (author)

  7. Anaerobic Biodegradability and Methane Potential of Crop Residue Co-Digested with Buffalo Dung

    Directory of Open Access Journals (Sweden)

    Abdul Razaque Sahito

    2013-07-01

    Full Text Available ABD (Anaerobic Biodegradability and BMP (Biochemical Methane Potential of banana plant waste, canola straw, cotton stalks, rice straw, sugarcane trash and wheat straw co-digested with buffalo dung was evaluated through AMPTS (Automatic Methane Potential Test System. The substrates were analyzed for moisture, TS (Total Solids and VS (Volatile Solids, ultimate analysis (CHONS, pH and TA (Total Alkalinity. The BMPobserved during incubation of 30 days at the temperature of 37±0.2°C was 322 Nml CH4/g VSadd for wheat straw followed by 260, 170, 149, 142 and 138 Nml CH4/gVSadd for canola straw, rice straw, cotton stalks, banana plant waste and sugarcane trash respectively, whereas the maximum theoretical BMP was 481 Nml CH4/gVSadd for cotton stalks, followed by 473, 473, 446, 432 and 385 Nml CH4/gVSadd for wheat straw, banana plant waste, canola straw, rice straw and sugarcane trash respectively. The percentage ABD values were in the range of 68-30%. In addition to this, the effect of lignin content in the crop residue was evaluated on the ABD. The results of this study indicate that, the co-digestion of the crop residues with buffalo dung is feasible for production of renewable methane

  8. A Metagenomic Advance for the Cloning and Characterization of a Cellulase from Red Rice Crop Residues

    Directory of Open Access Journals (Sweden)

    Carlos Meneses

    2016-06-01

    Full Text Available Many naturally-occurring cellulolytic microorganisms are not readily cultivable, demanding a culture-independent approach in order to study their cellulolytic genes. Metagenomics involves the isolation of DNA from environmental sources and can be used to identify enzymes with biotechnological potential from uncultured microbes. In this study, a gene encoding an endoglucanase was cloned from red rice crop residues using a metagenomic strategy. The amino acid identity between this gene and its closest published counterparts is lower than 70%. The endoglucanase was named EglaRR01 and was biochemically characterized. This recombinant protein showed activity on carboxymethylcellulose, indicating that EglaRR01 is an endoactive lytic enzyme. The enzymatic activity was optimal at a pH of 6.8 and at a temperature of 30 °C. Ethanol production from this recombinant enzyme was also analyzed on EglaRR01 crop residues, and resulted in conversion of cellulose from red rice into simple sugars which were further fermented by Saccharomyces cerevisiae to produce ethanol after seven days. Ethanol yield in this study was approximately 8 g/L. The gene found herein shows strong potential for use in ethanol production from cellulosic biomass (second generation ethanol.

  9. A Metagenomic Advance for the Cloning and Characterization of a Cellulase from Red Rice Crop Residues.

    Science.gov (United States)

    Meneses, Carlos; Silva, Bruna; Medeiros, Betsy; Serrato, Rodrigo; Johnston-Monje, David

    2016-06-25

    Many naturally-occurring cellulolytic microorganisms are not readily cultivable, demanding a culture-independent approach in order to study their cellulolytic genes. Metagenomics involves the isolation of DNA from environmental sources and can be used to identify enzymes with biotechnological potential from uncultured microbes. In this study, a gene encoding an endoglucanase was cloned from red rice crop residues using a metagenomic strategy. The amino acid identity between this gene and its closest published counterparts is lower than 70%. The endoglucanase was named EglaRR01 and was biochemically characterized. This recombinant protein showed activity on carboxymethylcellulose, indicating that EglaRR01 is an endoactive lytic enzyme. The enzymatic activity was optimal at a pH of 6.8 and at a temperature of 30 °C. Ethanol production from this recombinant enzyme was also analyzed on EglaRR01 crop residues, and resulted in conversion of cellulose from red rice into simple sugars which were further fermented by Saccharomyces cerevisiae to produce ethanol after seven days. Ethanol yield in this study was approximately 8 g/L. The gene found herein shows strong potential for use in ethanol production from cellulosic biomass (second generation ethanol).

  10. Effects of Carbon and Cover Crop Residues on N2O and N2 Emissions

    Science.gov (United States)

    Burger, M.; Cooperman, Y.; Horwath, W. R.

    2016-12-01

    In Mediterranean climate, nitrous oxide emissions occurring with the first rainfall after the dry summer season can contribute up to 50% of agricultural systems' total annual emissions, but the drivers of these emissions have not been clearly identified, and there are only few measurements of atmospheric nitrogen (N2) production (denitrification) during these events. In lab incubations, we investigated N2O and N2 production, gross ammonification and nitrification, and microbial N immobilization with wet-up in soil from a vineyard that was previously fallow or where cover crop residue had been incorporated the previous spring. Before the first rainfall, we measured 120 mg dissolved organic carbon (DOC-C) kg-1 soil in the 0-5 cm layer of this vineyard, and after the rain 10 mg DOC-C kg-1, while nitrate levels before the rain were cover cropped soil. The N2O/N2 production was 2, 7, 9, and 86% in fallow, legume-grass mixture, rye, and legume cover cropped soil. The N2O/N2 ratio tended to increase with lower DOC (post-rain) levels in the soil. The results suggest that accumulated carbon in dry surface soil is the main driving factor of N2O and N2 emissions through denitrification with the first rainfall after prolonged dry periods.

  11. Socio-ecological Niches for Minimum Tillage and Crop-residue Retention in Continuous Maize Cropping Systems in Smallholder Farms of Central Kenya

    NARCIS (Netherlands)

    Guto, S.N.; Pypers, P.; Vanlauwe, B.; Ridder, de N.; Giller, K.E.

    2012-01-01

    Soil fertility gradients develop on smallholder farms due to preferential allocation of inputs. A multi-location on-farm trial was conducted in Meru South, Central Kenya whose overall aim was to test minimum tillage and crop-residue retention practices in socio-ecological niches across heterogeneous

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

    Directory of Open Access Journals (Sweden)

    Ben-Hur Costa de Campos

    2011-06-01

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

  13. Effect of tillage and crop residues management on mungbean (vigna radiata (L.) wilczek) crop yield, nitrogen fixation and water use efficiency in rainfed areas

    International Nuclear Information System (INIS)

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

    2010-01-01

    A field experiment was conducted to study the effect of crop residues and tillage practices on BNF, WUE and yield of mungbean (Vigna radiata (L.) Wilczek) under semi arid rainfed conditions at the Livestock Research Station, Surezai, Peshawar in North West Frontier Province (NWFP) of Pakistan. The experiment comprised of two tillage i) conventional tillage (T1) and ii) no-tillage (T0) and two residues i) wheat crop residues retained (+) and ii) wheat crop residues removed (-) treatments. Basal doses of N at the rate of 20: P at the rate of 60 kg ha-1 were applied to mungbean at sowing time in the form of urea and single super phosphate respectively. Labelled urea having 5% 15N atom excess was applied at the rate of 20 kg N ha-1 as aqueous solution in micro plots (1m2) in each treatment plot to assess BNF by mungbean. Similarly, maize and sorghum were grown as reference crops and were fertilized with 15N labelled urea as aqueous solution having 1% 15N atom excess at the rate of 90 kg N ha/sup -1/. The results obtained showed that mungbean yield (grain/straw) and WUE were improved in notillage treatment as compared to tillage treatment. Maximum mungbean grain yield (1224 kg ha/sup -1/) and WUE (6.61kg ha/sup -1 mm/sup -1/) were obtained in no-tillage (+ residues) treatment. The N concentration in mungbean straw and grain was not significantly influenced by tillage or crop residue treatments. The amount of fertilizer-N taken up by straw and grain of mungbean was higher under no-tillage with residues-retained treatment but the differences were not significant. The major proportion of N (60.03 to 76.51%) was derived by mungbean crop from atmospheric N2 fixation, the remaining (19.6 to 35.91%) was taken up from the soil and a small proportion (3.89 to 5.89%) was derived from the applied fertilizer in different treatments. The maximum amount of N fixed by mungbean (82.59 kg ha/sup -1/) was derived in no-tillage with wheat residue-retained treatment. By using sorghum as

  14. Fertilizer nitrogen recovery efficiencies in crop production systems of China with and without consideration of the residual effect of nitrogen

    International Nuclear Information System (INIS)

    Yan, Xiaoyuan; Ti, Chaopu; Zhu, Zhaoliang; Vitousek, Peter; Chen, Deli; Leip, Adrian; Cai, Zucong

    2014-01-01

    China is the world’s largest consumer of synthetic nitrogen (N), where very low rates of fertilizer N recovery in crops have been reported, raising discussion around whether fertilizer N use can be significantly reduced without yield penalties. However, using recovery rates as indicator ignores a possible residual effect of fertilizer N—a factor often unknown at large scales. Such residual effect might store N in the soil increasing N availability for subsequent crops. The objectives of the present study were therefore to quantify the residual effect of fertilizer N in China and to obtain more realistic rates of the accumulative fertilizer N recovery efficiency (RE) in crop production systems of China. Long-term spatially-extensive data on crop production, fertilizer N and other N inputs to croplands in China were used to analyze the relationship between crop N uptake and fertilizer N input (or total N input), and to estimate the amount of residual fertilizer N. Measurement results of cropland soil N content in two time periods were obtained to compare the change in the soil N pool. At the provincial scale, it was found that there is a linear relationship between crop N uptake and fertilizer N input or total N input. With the increase in fertilizer N input, annual direct fertilizer N RE decreased and was indeed low (below 30% in recent years), while its residual effect increased continuously, to the point that 40–68% of applied fertilizer was used for crop production sooner or later. The residual effect was evidenced by a buildup of soil N and a large difference between nitrogen use efficiencies of long-term and short-term experiments. (paper)

  15. Thermogravimetry/mass spectrometry study of woody residues and an herbaceous biomass crop using PCA techniques

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, C.J.; Velo, E.; Puigjaner, L. [Department of Chemical Engineering, ETSEIB, Universitat Politecnica de Catalunya, Avinguda Diagonal 647, G2, E-08028 Barcelona (Spain); Meszaros, E.; Jakab, E. [Institute of Materials and Environmental Chemistry, Chemical Research Center, Hungarian Academy of Sciences, P.O. Box 17, Budapest 1525 (Hungary)

    2007-10-15

    The devolatilization behaviour of pine and beech wood from carpentry residuals and an herbaceous product from an energy plantation (artichoke thistle) was investigated by thermogravimetry/mass spectrometry (TG/MS). The effect of three pre-treatments, hot-water washing, ethanol extraction and their combination, was also studied. Principal component analysis (PCA) was employed to help in the evaluation of the large data set of results. The characteristics of the thermal decomposition of the herbaceous crop are considerably different from that of the woody biomass samples. The evolution profiles of some characteristic pyrolysis products revealed that the thermal behaviour of wood and thistle is still considerably different after the elimination of some of the inorganic ions and extractive compounds, although the macromolecular components of the samples decompose at similar temperatures. With the help of the PCA calculations, the effect of the different pre-treatments on the production of the main pyrolysis products was evidenced. (author)

  16. Environmental performance of crop residues as an energy source for electricity production

    DEFF Research Database (Denmark)

    Nguyen, T Lan T; Hermansen, John Erik; Mogensen, Lisbeth

    2013-01-01

    This paper aims to address the question, “What is the environmental performance of crop residues as an alternative energy source to fossil fuels, and whether and how can it be improved?”. In order to address the issue, we compare electricity production from wheat straw to that from coal and natural...... gas. The results on the environmental performance of straw for energy utilization and the two fossil fuel references are displayed first for different midpoint categories and then aggregated into a single score. The midpoint impact assessment shows that substitution of straw either for coal...... or for natural gas reduces global warming, non-renewable energy use, human toxicity and ecotoxicity, but increases eutrophication, respiratory inorganics, acidification and photochemical ozone. The results at the aggregate level show that the use of straw biomass for conversion to energy scores better than...

  17. Crop residues as a potential renewable energy source for Malawi's cement industry

    DEFF Research Database (Denmark)

    Gondwe, Kenneth J.; Chiotha, Sosten S.; Mkandawire, Theresa

    2017-01-01

    that the projected total energy demands in 2020, 2025 and 2030 were approximately 177 810 TJ, 184 210 TJ and 194 096 TJ respectively. The highest supply potentials were found to be in the central and southern regions of Malawi, coinciding with the locations of the two clinker plants. Crop residues could meet 45......-57% of the national total energy demand. The demand from the cement industry is only 0.8% of the estimated biomass energy potential. At an annual production of 600 000 t of clinker and 20% biomass co-firing with coal, 18 562 t of coal consumption would be avoided and 46 128 t of carbon dioxide emission reduction...

  18. Analyzing key constraints to biogas production from crop residues and manure in the EU—A spatially explicit model

    Science.gov (United States)

    Persson, U. Martin

    2017-01-01

    This paper presents a spatially explicit method for making regional estimates of the potential for biogas production from crop residues and manure, accounting for key technical, biochemical, environmental and economic constraints. Methods for making such estimates are important as biofuels from agricultural residues are receiving increasing policy support from the EU and major biogas producers, such as Germany and Italy, in response to concerns over unintended negative environmental and social impacts of conventional biofuels. This analysis comprises a spatially explicit estimate of crop residue and manure production for the EU at 250 m resolution, and a biogas production model accounting for local constraints such as the sustainable removal of residues, transportation of substrates, and the substrates’ biochemical suitability for anaerobic digestion. In our base scenario, the EU biogas production potential from crop residues and manure is about 0.7 EJ/year, nearly double the current EU production of biogas from agricultural substrates, most of which does not come from residues or manure. An extensive sensitivity analysis of the model shows that the potential could easily be 50% higher or lower, depending on the stringency of economic, technical and biochemical constraints. We find that the potential is particularly sensitive to constraints on the substrate mixtures’ carbon-to-nitrogen ratio and dry matter concentration. Hence, the potential to produce biogas from crop residues and manure in the EU depends to large extent on the possibility to overcome the challenges associated with these substrates, either by complementing them with suitable co-substrates (e.g. household waste and energy crops), or through further development of biogas technology (e.g. pretreatment of substrates and recirculation of effluent). PMID:28141827

  19. Analyzing key constraints to biogas production from crop residues and manure in the EU-A spatially explicit model.

    Science.gov (United States)

    Einarsson, Rasmus; Persson, U Martin

    2017-01-01

    This paper presents a spatially explicit method for making regional estimates of the potential for biogas production from crop residues and manure, accounting for key technical, biochemical, environmental and economic constraints. Methods for making such estimates are important as biofuels from agricultural residues are receiving increasing policy support from the EU and major biogas producers, such as Germany and Italy, in response to concerns over unintended negative environmental and social impacts of conventional biofuels. This analysis comprises a spatially explicit estimate of crop residue and manure production for the EU at 250 m resolution, and a biogas production model accounting for local constraints such as the sustainable removal of residues, transportation of substrates, and the substrates' biochemical suitability for anaerobic digestion. In our base scenario, the EU biogas production potential from crop residues and manure is about 0.7 EJ/year, nearly double the current EU production of biogas from agricultural substrates, most of which does not come from residues or manure. An extensive sensitivity analysis of the model shows that the potential could easily be 50% higher or lower, depending on the stringency of economic, technical and biochemical constraints. We find that the potential is particularly sensitive to constraints on the substrate mixtures' carbon-to-nitrogen ratio and dry matter concentration. Hence, the potential to produce biogas from crop residues and manure in the EU depends to large extent on the possibility to overcome the challenges associated with these substrates, either by complementing them with suitable co-substrates (e.g. household waste and energy crops), or through further development of biogas technology (e.g. pretreatment of substrates and recirculation of effluent).

  20. Analyzing key constraints to biogas production from crop residues and manure in the EU-A spatially explicit model.

    Directory of Open Access Journals (Sweden)

    Rasmus Einarsson

    Full Text Available This paper presents a spatially explicit method for making regional estimates of the potential for biogas production from crop residues and manure, accounting for key technical, biochemical, environmental and economic constraints. Methods for making such estimates are important as biofuels from agricultural residues are receiving increasing policy support from the EU and major biogas producers, such as Germany and Italy, in response to concerns over unintended negative environmental and social impacts of conventional biofuels. This analysis comprises a spatially explicit estimate of crop residue and manure production for the EU at 250 m resolution, and a biogas production model accounting for local constraints such as the sustainable removal of residues, transportation of substrates, and the substrates' biochemical suitability for anaerobic digestion. In our base scenario, the EU biogas production potential from crop residues and manure is about 0.7 EJ/year, nearly double the current EU production of biogas from agricultural substrates, most of which does not come from residues or manure. An extensive sensitivity analysis of the model shows that the potential could easily be 50% higher or lower, depending on the stringency of economic, technical and biochemical constraints. We find that the potential is particularly sensitive to constraints on the substrate mixtures' carbon-to-nitrogen ratio and dry matter concentration. Hence, the potential to produce biogas from crop residues and manure in the EU depends to large extent on the possibility to overcome the challenges associated with these substrates, either by complementing them with suitable co-substrates (e.g. household waste and energy crops, or through further development of biogas technology (e.g. pretreatment of substrates and recirculation of effluent.

  1. Renewable energy from pyrolysis using crops and agricultural residuals: An economic and environmental evaluation

    International Nuclear Information System (INIS)

    Kung, Chih-Chun; Zhang, Ning

    2015-01-01

    This study examines pyrolysis-based electricity generation and ethanol production using various crops and agricultural residuals in Taiwan. It analyzes the net economic and environmental effects within the framework of the Extended Taiwanese Agricultural Sector Model by incorporating ongoing and potential gasoline, coal and GHG (greenhouse gas) prices. The study discusses the effects of agricultural shifts, which have several important implications for the Taiwanese bioenergy development. First, the cost of collecting rice straw is much lower than the production cost of other energy crops, implying that the efficient use of agricultural waste may eventually result in positive social effects in terms of farmers' revenue, the renewable energy supply and GHG emissions offset. Second, farmers with idle land usually suffer a lower steady income. Encouraging the development of the renewable energy industry increases the demand of raw feedstocks, which involves converting the idle land into cultivation and increasing farmers' revenue. Third, agricultural waste is usually burned and emits CO_2, which accelerates the global climate shift. Approximately one third of emissions could be offset by rice straw-based bioenergy in certain cases. Turning this waste into bioenergy, which offsets net GHG emissions, has positive effects on the climate change mitigation. - Highlights: • Pyrolyzing rice straw provides considerable energy supply (max 4.68 billion kWh). • High emission offset when combined with rice straw (max 2.73 million tons). • Affordable government subsidy ($204 million a year). • Collection and transportation costs of wastes could impact the result significantly.

  2. Reflectance measurements of leaves for detecting visible and non-visible ozon damage to crops

    International Nuclear Information System (INIS)

    Kraft, M.; Weigel, H.-J.; Mejer, G.-J.; Brandes, F.

    1996-01-01

    Spring wheat (Triticum aestivum cv. Turbo), white clover (Trifolium repens cv. Karina) and maize (Zea mays cv. Bonny) plants were exposed for 20–30 days in open top chambers to charcoal-filtered air (CF, control) and CF air supplied with O 3 for 8–12 h/per day in the concentration range of 180–240 μg O 3 /m 3 (8–12 h/day treatment mean). At the end of the O 3 treatment spectral reflectance measurements were made on single leaves of all 3 species and on canopies of wheat and clover using a CCD (Charged Coupled Device) camera and wavelength filters with 11 wavelength bands ranging from 450 nm to 950 nm. Different vegetation indices such as the normalized difference vegetation index (NDVI) and the ≪main inflection point≫ (MIP) were calculated. Based on these results it was shown that visible O 3 damages were correlated to the spectral reflectance changes: Both leaves and canopies showed an increased reflectance of visible light after ozone treatment. While clover and maize leaves as well as clover and wheat canopies showed a decreased near infrared (NIR) reflectance, the NIR reflectance of wheat leaves did not change, even if the leaves had visible symptoms. A decreased infrared reflectance was detectable for all clover leaves after O 3 treatment although for part of the leaves no visible foliar damage symptoms could be observed

  3. Photodegradation of bentazon, clopyralid, and triclopyr on model leaves: importance of a systematic evaluation of pesticide photostability on crops.

    Science.gov (United States)

    Eyheraguibel, Boris; Ter Halle, Alexandra; Richard, Claire

    2009-03-11

    Photolyses of three herbicides, bentazon, clopyralid, and triclopyr, were studied on plant leaves after crop treatment. The experiments were carried out on cuticular wax films, which are good models for leaf surfaces. The pure compounds and their commercial formulations were investigated under simulated solar light. At the recommended agricultural application rates, the three formulated herbicides photolyzed more rapidly on films than on soil or in water. Their photolysis is likely to be an important dissipation path from crops after treatment. The effects induced by the adjuvants in formulations were varied. Adjuvants slowed the photodegradation of bentazon slightly. In Garlon, in which triclopyr and clopyralid are combined, the adjuvants did not affect the photolysis of clopyralid even though they accelerated the rate of photolysis of triclopyr by a factor of 7. The kinetics were also affected by the application rates. This work also underscores the importance of assessing the photoreactivity of active ingredients in conditions similar to those of their application.

  4. Long-term stabilization of crop residues and soil organic carbon affected by residue quality and initial soil pH.

    Science.gov (United States)

    Wang, Xiaojuan; Butterly, Clayton R; Baldock, Jeff A; Tang, Caixian

    2017-06-01

    Residues differing in quality and carbon (C) chemistry are presumed to contribute differently to soil pH change and long-term soil organic carbon (SOC) pools. This study examined the liming effect of different crop residues (canola, chickpea and wheat) down the soil profile (0-30cm) in two sandy soils differing in initial pH as well as the long-term stability of SOC at the amended layer (0-10cm) using mid-infrared (MIR) and solid-state 13 C nuclear magnetic resonance (NMR) spectroscopy. A field column experiment was conducted for 48months. Chickpea- and canola-residue amendments increased soil pH at 0-10cm in the Podzol by up to 0.47 and 0.36units, and in the Cambisol by 0.31 and 0.18units, respectively, at 48months when compared with the non-residue-amended control. The decomposition of crop residues was greatly retarded in the Podzol with lower initial soil pH during the first 9months. The MIR-predicted particulate organic C (POC) acted as the major C sink for residue-derived C in the Podzol. In contrast, depletion of POC and recovery of residue C in MIR-predicted humic organic C (HOC) were detected in the Cambisol within 3months. Residue types showed little impact on total SOC and its chemical composition in the Cambisol at 48months, in contrast to the Podzol. The final HOC and resistant organic C (ROC) pools in the Podzol amended with canola and chickpea residues were about 25% lower than the control. This apparent priming effect might be related to the greater liming effect of these two residues in the Podzol. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. PM2.5 emissions and source profiles from open burning of crop residues

    Science.gov (United States)

    Ni, Haiyan; Tian, Jie; Wang, Xiaoliang; Wang, Qiyuan; Han, Yongming; Cao, Junji; Long, Xin; Chen, L.-W. Antony; Chow, Judith C.; Watson, John G.; Huang, Ru-Jin; Dusek, Ulrike

    2017-11-01

    Wheat straw, rice straw, and corn stalks, the major agricultural crop residues in China, were collected from six major crop producing regions, and burned in a laboratory combustion chamber to determine PM2.5 source profiles and speciated emission factors (EFs). Organic carbon (OC) and water-soluble ions (the sum of NH4+, Na+, K+, Mg2+, Ca2+, Cl-, NO3- and SO42-) are major constituents, accounting for 43.1 ± 8.3% and 27.4 ± 14.6% of PM2.5, respectively. Chloride (Cl-) and water-soluble potassium (K+) are the dominant ionic species, with an average abundance of 14.5 ± 8.2% and 6.4 ± 4.4% in PM2.5, respectively. The average K+/Cl- ratio is ∼0.4, lower than 2.8-5.4 for wood combustion. Similarity measures (i.e., Student's t-test, coefficient of divergence, correlations, and residual to uncertainty ratios) show the crop profiles are too similar for the species measured to be resolved from one another by receptor modeling. The largest difference was found between rice straw and corn stalk emissions, with higher OC and lower Cl- and K+ abundances (50%, 8%, and 3% of PM2.5, respectively) for corn stalks; lower OC, and higher Cl- and K+ abundances (38%, 21%, and 10% of PM2.5, respectively) for rice straw. Average EFs were 4.8 ± 3.1 g kg-1 for OC, 1.3 ± 0.8 g kg-1 for Cl- and 0.59 ± 0.56 g kg-1 for K+. Flaming and smoldering combustions resulted in an average modified combustion efficiency (MCE) of 0.92 ± 0.03, and low elemental carbon (EC) EFs (0.24 ± 0.12 g kg-1). OC/EC ratios from individual source profiles ranged from 12.9 ± 4.3 for rice straw to 24.1 ± 13.5 for wheat straw. The average K+/EC ratio was 2.4 ± 1.5, an order of magnitude higher than those from residential wood combustion (0.2-0.76). Elevated emission rates were found for OC (387 Gg yr-1) and Cl- (122 Gg yr-1), accounting for 44% and 14% of 2008 PM2.5 emissions in China.

  6. Integrating biological treatment of crop residue into a hydroponic sweetpotato culture

    Science.gov (United States)

    Trotman, A. A.; David, P. P.; Bonsi, C. K.; Hill, W. A.; Mortley, D. G.; Loretan, P. A.

    1997-01-01

    Residual biomass from hydroponic culture of sweetpotato [Ipomoea batatas (L.) Lam.] was degraded using natural bacterial soil isolates. Sweetpotato was grown for 120 days in hydroponic culture with a nutrient solution comprised of a ratio of 80% modified half Hoagland solution to 20% filtered effluent from an aerobic starch hydrolysis bioreactor. The phytotoxicity of the effluent was assayed with `Waldmann's Green' lettuce (Lactuca sativa L.) and the ratio selected after a 60-day bioassay using sweetpotato plants propagated vegetatively from cuttings. Controlled environment chamber experiments were conducted to investigate the impact of filtrate from biological treatment of crop residue on growth and storage root production with plants grown in a modified half Hoagland solution. Incorporation of bioreactor effluent, reduced storage root yield of `Georgia Jet' sweetpotato but the decrease was not statistically significant when compared with yield for plants cultured in a modified half Hoagland solution without filtrate. However, yield of `TU-82-155' sweetpotato was significantly reduced when grown in a modified half Hoagland solution into which filtered effluent had been incorporated. Total biomass was significantly reduced for both sweetpotato cultivars when grown in bioreactor effluent. The leaf area and dry matter accumulation were significantly (P < 0.05) reduced for both cultivars when grown in solution culture containing 20% filtered effluent.

  7. Nitrous oxide and N-leaching losses from agricultural soil: Influence of crop residue particle size, quality and placement

    DEFF Research Database (Denmark)

    Ambus, P.; Jensen, E.S.; Robertson, G.P.

    2001-01-01

    protection of the crop residue material against microbial attack. Leaching of N tended to be reduced about 40 % with barley and 20 % with pea, but the numbers were not significantly different from residue-free soil, which leached 4.7-4.9 g N m(-2). When wheat and alfalfa residues were mixed into the soil N2O...... emissions increased 6.5 and 1.6 times, respectively, compared with residue placed in a layer. Wheat residue in a layer evolved 3.4-times less N2O than alfalfa in a layer, whereas when mixed the two residue types evolved similar amounts of N2O. This difference was probably due to N-limitations in localised...

  8. Investigation of Sensitivity of Some Pulses and Agronomic Crops to Soil Residue of Idosulfuron-mesosulfurun Herbicide

    Directory of Open Access Journals (Sweden)

    E. Izadi-Darbandi

    2013-03-01

    Full Text Available To study the sensitivity of chick pea, bean, lentil, rapeseed, sugarbeet and tomato to soil residual concentration of Idosulfuron-mesosulfurun herbicide, an experiment was carried out under controlled conditions at the College of Agriculture, Ferdowsi University of Mashhad, Iran, in 2010. The studied factors were the 6 mentioned crops, and 7 levels of soil residual concentration of Idosulfuron-mesosulfurun herbicide (0, 0.0015, 0.0037, 0.0079, 0.015, 0.031 and 0.047 mg per kg of soil. The factorial experiment was carried out as a completely randomized design with three replications. Crops' emergence percentage was determined one week after their emergence. Plants' survival percentage and shoot and root biomass production were measured 30 days after their emergence. Results showed that all mentioned characteristics decreased significantly (P<0.01 in the presence of soil residue of the herbicide. Increasing Idosulfuron-mesosulfurun residual concentration in soil decreased emergence and shoot and root biomass production. Bean had the lowest shoot (44% and root (66.78% biomass loss and tomato had the highest shoot (96.38% and root (89.64% biomass loss. Based on ED50 index, pea (0.0079 mg/kg soil was the most tolerant and tomato (0.0003 mg/kg soil was the most susceptible crop to soil residues of Idosulfuron-mesosulfurun, and other crops ranked in between as: tomato< sugarbeet< rapeseed< lentil< bean< pea. In general, these results showed that soil residue of Idosulfuron-mesosulfurun can injure rotation crops and it is important to consider their sensitivity in rotation programming.

  9. The Effect of Crop Residue and Different NPK Fertilizer Rates on yield Components and Yield of Wheat

    Directory of Open Access Journals (Sweden)

    fatemeh khamadi

    2017-08-01

    Full Text Available Introduction Integrated nutrient management involving crop residue/green manures and chemical fertilizer is potential alternative to provide a balanced supply of nutrients, enhance soil quality and thereby sustain higher productivity. The present experiment was undertaken to evaluate the effect of different crop residue management practices and NPK levels on yield components and yield of wheat. Materials and methods Field experiments were conducted during 2012-2014 at department of agronomy, Chamran University. Experiment was laid out in a randomized block designs in split plot arrangement. With three replications. Crop residues were assigned to main plot consistent CR1: wheat residue; CR2: rape residue; CR3: barley residue; CR4: barley residue + vetch; CR5: wheat straw + mungbean; CR6: vetch residue; CR7: mungbean residue; CR8: No residue incorporation as main plot and three NPK fertilizer rates: F1: (180N-120P-100K kg.ha-1; F2: (140N-90P-80K kg.ha-1; F3: (90N-60P-40K kg.ha-1 as sub plots. Twelve hills were collected at physiological maturity for measuring yield components from surrounding area of grain yield harvest area. Yield components, viz. number of spike per m2, seed per spike, 1000- grain weight, plant height were measured. Grain and straw yields were recorded from the central 5 m2 grain yield harvest area of each treatment and harvest index was calculated. Data were subjected to analysis by SAS and mean companions were performed using the Duncan multiple range test producer. Also, graphs were drawn in Excel software. Results and discussion The result of analysis variance showed significant difference between crop residues for evaluated traits. The result indicated that the highest biological and grain yield was obtained when wheat treated with CR5: wheat straw + mungbean (green manure and CR4: barley straw + vetch (green manure. Biological and grain yield increased 31 and 26% respectively by CR5 comparing with control. The highest

  10. Evaluation of certain crop residues for carbohydrate and protein fractions by cornell net carbohydrate and protein system

    Directory of Open Access Journals (Sweden)

    Venkateswarulu Swarna

    2015-06-01

    Full Text Available Four locally available crop residues viz., jowar stover (JS, maize stover (MS, red gram straw (RGS and black gram straw (BGS were evaluated for carbohydrate and protein fractions using Cornell Net Carbohydrate and Protein (CNCP system. Lignin (% NDF was higher in legume straws as compared to cereal stovers while Non-structural carbohydrates (NSC (% DM followed the reverse trend. The carbohydrate fractions A and B1 were higher in BGS while B2 was higher in MS as compared to other crop residues. The unavailable cell wall fraction (C was higher in legume straws when compared to cereal stovers. Among protein fractions, B1 was higher in legume straws when compared to cereal stovers while B2 was higher in cereal stovers as compared to legume straws. Fraction B3 largely, bypass protein was highest in MS as compared to other crop residues. Acid detergent insoluble crude protein (ADICP (% CP or unavailable protein fraction C was lowest in MS and highest in BGS. It is concluded that MS is superior in nutritional value for feeding ruminants as compared to other crop residues.

  11. Woody legume fallow productivity, biological N2-fixation and residual benefits to two successive maize crops in Zimbabwe

    NARCIS (Netherlands)

    Chikowo, R.; Mapfumo, P.; Nyamugafata, P.; Giller, K.E.

    2004-01-01

    Three woody legumes were planted as two-year 'improved fallows' to evaluate their residual nitrogen (N) effects on two subsequent maize crops under minimum and conventional tillage management. Maize monoculture and cowpea-maize-maize sequence treatments were included as controls. N-2-fixation was

  12. Distribution, timing of attack, and oviposition of the banana weevil, Cosmopolites sordidus, on banana crop residues in Uganda

    NARCIS (Netherlands)

    Masanza, M.; Gold, C.S.; Huis, van A.

    2005-01-01

    Crop sanitation (removal and chopping of residue corms and pseudostems following plant harvest) has been recommended as a 'best bet' means of reducing banana weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae), populations. However, it has been unclear when such practices should be

  13. Earthworm-induced N2O emissions in a sandy soil with surface-applied crop residues

    NARCIS (Netherlands)

    Giannopoulos, G.; Groenigen, van J.W.; Pulleman, M.M.

    2011-01-01

    Earlier research with endogeic and epigeic earthworm species in loamy arable soil has shown that both earthworm groups can increase nitrous oxide (N2O) emissions, provided that crop residue placement matches the feeding strategy of the earthworm ecological group(s). However, it is not yet clear

  14. Emission factors of polycyclic and nitro-polycyclic aromatic hydrocarbons from residential combustion of coal and crop residue pellets.

    Science.gov (United States)

    Yang, Xiaoyang; Liu, Shijie; Xu, Yisheng; Liu, Yu; Chen, Lijiang; Tang, Ning; Hayakawa, Kazuichi

    2017-12-01

    Polycyclic aromatic hydrocarbons (PAHs) and nitro-polycyclic aromatic hydrocarbons (NPAHs) are toxic pollutants mainly produced during fossil fuel combustion. Domestic coal stoves, which emit large amounts of PAHs and NPAHs, are widely used in the Chinese countryside. In this study, emission factors (Efs) for 13 PAH species and 21 NPAH species for four raw coal (three bituminous and one anthracite), one honeycomb briquette, and one crop residue pellet (peanut hulls) samples burned in a typical Chinese rural cooking stove were determined experimentally. The PAH and NPAH Efs for the six fuels were 3.15-49 mg/kg and 0.32-100 μg/kg, respectively. Peanut hulls had very high Efs for both PAHs and NPAHs, and honeycomb briquettes had the lowest Efs. 2-Nitropyrene and 2-nitrofluoranthene, which are NPAHs typically found in secondary organic aerosol, were detected in the emissions from some fuels, suggesting that chemical reactions may have occurred in the dilution tunnel between the flue gas leaving the stove and entering the sampler. The 1-nitropyrene to pyrene diagnostic ratios for coal and peanut hulls were 0.0001 ± 0.0001 and 0.0005, respectively. These were in the same order of magnitude as reference ratios for emissions during coal combustion. The 6-nitrobenzo[a]pyrene to benzo[a]pyrene ratios for the fuels were determined, and the ratios for coal and peanut hulls were 0.0010 ± 0.0001 and 0.0014, respectively. The calculated potential toxic risks indicated that peanut hull emissions were very toxic, especially in terms of NPAHs, compared with emissions from the other fuels. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Effect of tillage and crop residue on soil temperature following planting for a Black soil in Northeast China.

    Science.gov (United States)

    Shen, Yan; McLaughlin, Neil; Zhang, Xiaoping; Xu, Minggang; Liang, Aizhen

    2018-03-14

    Crop residue return is imperative to maintain soil health and productivity but some farmers resist adopting conservation tillage systems with residue return fearing reduced soil temperature following planting and crop yield. Soil temperatures were measured at 10 cm depth for one month following planting from 2004 to 2007 in a field experiment in Northeast China. Tillage treatments included mouldboard plough (MP), no till (NT), and ridge till (RT) with maize (Zea mays L.) and soybean (Glycine max Merr.) crops. Tillage had significant effects on soil temperature in 10 of 15 weekly periods. Weekly average NT soil temperature was 0-1.5 °C lower than MP, but the difference was significant (P Northeast China representative of a cool to temperate zone.

  16. Residues of diflubenzuron on horse chestnut (Aesculus hippocastanum) leaves and their efficacy against the horse chestnut leafminer, Cameraria ohridella.

    Science.gov (United States)

    Nejmanová, Jana; Cvacka, Josef; Hrdý, Ivan; Kuldová, Jelena; Mertelík, Josef; Muck, Alexander; Nesnerová, Petra; Svatos, Ales

    2006-03-01

    Residues of the insect growth regulator diflubenzuron were quantified on horse chestnut (Aesculus hippocastanum L.) leaves treated with a diflubenzuron 480 g litre(-1) SC, Dimilin. To analyse the samples, an analytical procedure was developed involving a simple extraction step followed by high-performance liquid chromatography on an octadecyl-modified silica column with methanol + 0.01 M ammonium acetate mobile phase. The results showed diflubenzuron to be highly stable on horse chestnut leaves; more than 4 months (127 days) after application, 38% (on average) of the insecticide still remained on/in the leaves. The data confirmed biological observations showing diflubenzuron's long-term efficacy against the horse chestnut leafminer, Cameraria ohridella Deschka and Dimić, which is the most important pest of the horse chestnut in Europe. The hypothesis of possible penetration of diflubenzuron into the leaf mass is explored and discussed.

  17. Occurrence and Residue Pattern of Phthalate Esters in Fresh Tea Leaves and during Tea Manufacturing and Brewing.

    Science.gov (United States)

    Liu, Pingxiang; Chen, Hongping; Gao, Guanwei; Hao, Zhenxia; Wang, Chen; Ma, Guicen; Chai, Yunfeng; Zhang, Lin; Liu, Xin

    2016-11-23

    The residues of 16 phthalate esters (PAEs) in fresh tea leaves and made tea were determined via gas chromatography-tandem mass spectrometry to study their distribution and degradation characteristics during tea planting and processing. Five PAEs were detected in all fresh tea leaves, and higher concentrations were detected in mature leaves. The distribution of PAEs in fresh tea leaves ranged from 69.7 to 2244.0 μg/kg. The degradative percentages of ∑ 5 PAEs during green tea manufacturing ranged from 61 to 63% and were significantly influenced by the drying process. The transfer rates of PAEs-D 4 ranged from 5.2 to 100.6%. PAEs with a high water solubility showed the highest transfer coefficient in the range of 91.8-100.6%, whereas PAEs with a high log K ow showed a low leaching efficiency below 11.9%. These results benefit the risk evaluation and establishment of a maximum residue limit for PAEs in tea.

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

    DEFF Research Database (Denmark)

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

    2017-01-01

    -term experiment on a loamy sand soil at Foulum in Denmark. All cropping systems included winter wheat, a leguminous crop (faba bean or grass-clover), potato and spring barley grown in different 4-crop rotations varying in strategies for N supply (fertilizer/manure type and rate, use of catch crops and green......-N leaching losses ranged from 39 to 56 kg N ha−1 y−1 and were lowest in rotations with catch crops; leaching was not correlated with N surplus or N input in fertilizer or manure. Crop yields of the organic rotations were 25 to 37% lower than in identical conventional rotations. As a consequence, yield...

  19. Soil and crop residue CO2-C emission under tillage systems in sugarcane-producing areas of southern Brazil

    Directory of Open Access Journals (Sweden)

    Luís Gustavo Teixeira

    2013-10-01

    Full Text Available Appropriate management of agricultural crop residues could result in increases on soil organic carbon (SOC and help to mitigate gas effect. To distinguish the contributions of SOC and sugarcane (Saccharum spp. residues to the short-term CO2-C loss, we studied the influence of several tillage systems: heavy offset disk harrow (HO, chisel plow (CP, rotary tiller (RT, and sugarcane mill tiller (SM in 2008, and CP, RT, SM, moldboard (MP, and subsoiler (SUB in 2009, with and without sugarcane residues relative to no-till (NT in the sugarcane producing region of Brazil. Soil CO2-C emissions were measured daily for two weeks after tillage using portable soil respiration systems. Daily CO2-C emissions declined after tillage regardless of tillage system. In 2008, total CO2-C from SOC and/or residue decomposition was greater for RT and lowest for CP. In 2009, emission was greatest for MP and CP with residues, and smallest for NT. SOC and residue contributed 47 % and 41 %, respectively, to total CO2-C emissions. Regarding the estimated emissions from sugarcane residue and SOC decomposition within the measurement period, CO2-C factor was similar to sugarcane residue and soil organic carbon decomposition, depending on the tillage system applied. Our approach may define new emission factors that are associated to tillage operations on bare or sugarcane-residue-covered soils to estimate the total carbon loss.

  20. Cellulosic biofuels from crop residue and groundwater extraction in the US Plains: the case of Nebraska.

    Science.gov (United States)

    Sesmero, Juan P

    2014-11-01

    This study develops a model of crop residue (i.e. stover) supply and derived demand for irrigation water accounting for non-linear effects of soil organic matter on soil's water holding capacity. The model is calibrated for typical conditions in central Nebraska, United States, and identifies potential interactions between water and biofuel policies. The price offered for feedstock by a cost-minimizing plant facing that stover supply response is calculated. Results indicate that as biofuel production volumes increase, soil carbon depletion per unit of biofuel produced decreases. Consumption of groundwater per unit of biofuel produced first decreases and then increases (after a threshold of 363 dam(3) of biofuels per year) due to plants' increased reliance on the extensive margin for additional biomass. The analysis reveals a tension between biofuel and water policies. As biofuel production raises the economic benefits of relaxing water conservation policies (measured by the "shadow price" of water) increase. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Carbon balance and crop residue management in dynamic equilibrium under a no-till system in Campos Gerais

    Directory of Open Access Journals (Sweden)

    Ademir de Oliveira Ferreira

    2012-11-01

    Full Text Available The adoption of no-tillage systems (NT and the maintenance of crop residues on the soil surface result in the long-term increase of carbon (C in the system, promoting C sequestration and reducing C-CO2 emissions to the atmosphere. The purpose of this study was to evaluate the C sequestration rate and the minimum amount of crop residues required to maintain the dynamic C equilibrium (dC/dt = 0 of two soils (Typic Hapludox with different textural classes. The experiment was arranged in a 2 x 2 x 2 randomized block factorial design. The following factors were analyzed: (a two soil types: Typic Hapludox (Oxisol with medium texture (LVTM and Oxisol with clay texture (LVTA, (b two sampling layers (0-5 and 5-20 cm, and (c two sampling periods (P1 - October 2007; P2 - September 2008. Samples were collected from fields under a long-term (20 years NT system with the following crop rotations: wheat/soybean/black oat + vetch/maize (LVTM and wheat/maize/black oat + vetch/soybean (LVTA. The annual C sequestration rates were 0.83 and 0.76 Mg ha-1 for LVTM and LVTA, respectively. The estimates of the minimum amount of crop residues required to maintain a dynamic equilibrium (dC/dt = 0 were 7.13 and 6.53 Mg ha-1 year-1 for LVTM and LVTA, respectively. The C conversion rate in both studied soils was lower than that reported in other studies in the region, resulting in a greater amount of crop residues left on the soil surface.

  2. The Effect of Conservation Tillage and Cover Crop Residue on Beneficial Arthropods and Weed Seed Predation in Acorn Squash.

    Science.gov (United States)

    Quinn, N F; Brainard, D C; Szendrei, Z

    2016-12-01

    Conservation tillage combined with cover crops or mulching may enhance natural enemy activity in agroecosystems by reducing soil disturbance and increasing habitat structural complexity. In particular, weed seed predation can increase with vegetation cover and reduced tillage, indicating that mulches may improve the quality of the habitat for weed seed foraging. The purpose of this study was to quantify the effects of tillage and mulching for conservation biological control in cucurbit fields. The effects of mulch and reduced tillage on arthropods and rates of weed seed loss from arenas were examined in field trials on sandy soils in 2014 and 2015. Experimental factors included tillage and cover crop, each with two levels: strip-tillage or full-tillage, and cover crop mulch (rye residue) or no cover crop mulch (unmulched). Arthropod abundance on the crop foliage was not affected by tillage or cover crops. Contrary to expectations, epigeal natural enemies of insects and rates of weed seed removal either did not respond to treatments or were greater in full-tilled plots and plots without mulch. Our study demonstrates the potential importance of weed seed predators in reducing weed seedbanks in vegetable agroecosystems, and suggests that early-season tillage may not be detrimental to epigeal predator assemblages. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. GHG AND AEROSOL EMISSION FROM FIRE PIXEL DURING CROP RESIDUE BURNING UNDER RICE AND WHEAT CROPPING SYSTEMS IN NORTH-WEST INDIA

    Directory of Open Access Journals (Sweden)

    P. Acharya

    2016-10-01

    Full Text Available Emission of smoke and aerosol from open field burning of crop residue is a long-standing subject matter of atmospheric pollution. In this study, we proposed a new approach of estimating fuel load in the fire pixels and corresponding emissions of selected GHGs and aerosols i.e. CO2, CO, NO2, SO2, and total particulate matter (TPM due to burning of crop residue under rice and wheat cropping systems in Punjab in north-west India from 2002 to 2012. In contrasts to the conventional method that uses RPR ratio to estimate the biomass, fuel load in the fire pixels was estimated as a function of enhanced vegetation index (EVI. MODIS fire products were used to detect the fire pixels during harvesting seasons of rice and wheat. Based on the field measurements, fuel load in the fire pixels were modelled as a function of average EVI using second order polynomial regression. Average EVI for rice and wheat crops that were extracted through Fourier transformation were computed from MODIS time series 16 day EVI composites. About 23 % of net shown area (NSA during rice and 11 % during wheat harvesting seasons are affected by field burning. The computed average fuel loads are 11.32 t/ha (±17.4 during rice and 10.89 t/ha (±8.7 during wheat harvesting seasons. Calculated average total emissions of CO2, CO, NO2, SO2 and TPM were 8108.41, 657.85, 8.10, 4.10, and 133.21 Gg during rice straw burning and 6896.85, 625.09, 1.42, 1.77, and 57.55 Gg during wheat burning. Comparison of estimated values shows better agreement with the previous concurrent estimations. The method, however, shows its efficiency parallel to the conventional method of estimation of fuel load and related pollutant emissions.

  4. Cofermentation of energy crops and organic residues; Ergebnisse der Kovergaerung von Energiepflanzen und organischen Reststoffen

    Energy Technology Data Exchange (ETDEWEB)

    Linke, B. [Institut fuer Agrartechnik Bornim e.V. (ATB), Potsdam-Bornim (Germany); Vollmer, G.R. [Biotechnologie Nordhausen (BTN) (Germany)

    2002-07-01

    There are currently more than 1500 agricultural biogas plans in Germany, most of which work by the liquid fermentation principle which is commercially available. At a mean hydraulic time of residue of 20 - 30 days and a charge of about 1.5 to 4 kg of organic matter m{sup -1}d{sup -1}, about 350 - 550 l of biogas can be produced per kg of organic matter (liquid or solid manure). Biogas yields are higher for cofermentation of liquid manure with energy crops and/or high-energy organic residues. Some figures are given: About 1000 l per kg{sup -1} for beetroot, pressed pellets of rape, sugarbeet, or rye, 600 - 700 l per kg{sup -1} for grass, malt residuum, sugar pulp, grape cake or potato pulp. In the case of silo-fermented corn, yields were higher than reported in earlier publications, i.e. about 800 instead of 200 l per kg{sup -1}. [German] Die Gewinnung von Biogas aus Guelle, Stallmist, pflanzlichen Biomassen oder organischen Reststoffen aus der Agro- oder Lebensmittelindustrie leistet heute durch das EEG in ueber 1500 Landwirtschaftsbetrieben Deutschlands einen Beitrag zur Sicherung des Einkommens. Die Landwirte nutzen hierfuer vorwiegend die Technik der Fluessigvergaerung, die von zahlreichen Firmen auf dem Markt angeboten werden. Bei mittleren hydraulischen Verweilzeiten von 20 bis 30 Tagen oder Faulraumbelastungen von etwa 1,5 bis 4 kg oS m{sup -3} d{sup -1} koennen aus Guelle oder Stallmist je kg zugefuehrte organische Substanz 350 bis 550 l Biogas gewonnen werden. Deutlich hoehere spezifische Biogasausbeuten erhaelt man durch die gemeinsame Vergaerung von Guelle mit Energiepflanzen und/oder energiereichen organischen Reststoffen (Kofermentation). Fuer Ruebensilage, Rapskuchen, Zuckerrueben-Pressschnitzel oder Roggen kann man oS-Biogasausbeuten von etwa 1000 l kg{sup -1} rechnen, waehrend sich der entsprechende Wert fuer Graeser, Schlempe, Melasse, Trester oder Kartoffelpuelpe im Bereich von 600 bis 700 l kg{sup -1} bewegt. Der in der Fachliteratur oft zu

  5. Biogas Production by Co-Digestion of Goat Manure with Three Crop Residues

    Science.gov (United States)

    Zhang, Tong; Liu, Linlin; Song, Zilin; Ren, Guangxin; Feng, Yongzhong; Han, Xinhui; Yang, Gaihe

    2013-01-01

    Goat manure (GM) is an excellent raw material for anaerobic digestion because of its high total nitrogen content and fermentation stability. Several comparative assays were conducted on the anaerobic co-digestion of GM with three crop residues (CRs), namely, wheat straw (WS), corn stalks (CS) and rice straw (RS), under different mixing ratios. All digesters were implemented simultaneously under mesophilic temperature at 35±1 °C with a total solid concentration of 8%. Result showed that the combination of GM with CS or RS significantly improved biogas production at all carbon-to-nitrogen (C/N) ratios. GM/CS (30:70), GM/CS (70:30), GM/RS (30:70) and GM/RS (50:50) produced the highest biogas yields from different co-substrates (14840, 16023, 15608 and 15698 mL, respectively) after 55 d of fermentation. Biogas yields of GM/WS 30:70 (C/N 35.61), GM/CS 70:30 (C/N 21.19) and GM/RS 50:50 (C/N 26.23) were 1.62, 2.11 and 1.83 times higher than that of CRs, respectively. These values were determined to be the optimal C/N ratios for co-digestion. However, compared with treatments of GM/CS and GM/RS treatments, biogas generated from GM/WS was only slightly higher than the single digestion of GM or WS. This result was caused by the high total carbon content (35.83%) and lignin content (24.34%) in WS, which inhibited biodegradation. PMID:23825574

  6. Survival of Diaporthe phaseolorum var. caulivora (causal agent of soybean stem canker) artificially inoculated in different crop residues

    OpenAIRE

    Grijalba, Pablo; Ridao, Azucena del C.

    2012-01-01

    Stem canker caused by Diaporthe phaseolorum var. caulivora is an important disease of soybean in Argentina. The objective of this study was to determine its survival ability in artificially infested straw under laboratory and field conditions. In laboratory, stem pieces of soybean, maize, sorghum, sunflower, potato and wheat were autoclaved, placed in petri dishes on Potato Dextrose Agar and Water Agar, and inoculated with a 7-day-old pathogen culture. All crop residues were colonized and pro...

  7. Potential use of edible crops in the phytoremediation of endosulfan residues in soil.

    Science.gov (United States)

    Mitton, Francesca M; Gonzalez, Mariana; Monserrat, José M; Miglioranza, Karina S B

    2016-04-01

    Endosulfan is a persistent and toxic organochlorine pesticide of banned or restricted use in several countries. It has been found in soil, water, and air and is bioaccumulated and magnified in ecosystems. Phytoremediation is a technology that promises effective and inexpensive cleanup of contaminated hazardous sites. The potential use of tomato, sunflower, soybean and alfalfa species to remove endosulfan from soil was investigated. All species were seeded and grown in endosulfan-spiked soils (8000 ng g(-1) dry weight) for 15 and 60 days. The phytoremediation potential was evaluated by studying the endosulfan levels and distribution in the soil-plant system, including the evaluation of soil dehydrogenase activity and toxic effects on plants. Plant endosulfan uptake leads to lower insecticide levels in the rhizosphere with regards to bulk soil or near root soil at 15 days of growth. Furthermore, plant growth-induced physical-chemical changes in soil were evidenced by differences in soil dehydrogenase activity and endosulfan metabolism. Sunflower showed differences in the uptake and distribution of endosulfan with regard to the other species, with a distribution pesticide pattern of aerial tissues > roots at 15 days of growth. Moreover, at 60 days, sunflower presented the highest pesticide levels in roots and leaves along with the highest phytoextraction capacity. Lipid peroxidation levels correlated positively with endosulfan accumulation, reflecting the negative effect of this insecticide on plant tissues. Considering biomass production and accumulation potential, in conjunction with the reduction of soil pesticide levels, sunflower plants seem to be the best phytoremediation candidate for endosulfan residues in soils. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Nitrous oxide emissions from yellow brown soil as affected by incorporation of crop residues with different carbon-to-nitrogen ratios: a case study in central China.

    Science.gov (United States)

    Lin, Shan; Iqbal, Javed; Hu, Ronggui; Shaaban, Muhammad; Cai, Jianbo; Chen, Xi

    2013-08-01

    To investigate the influence of crop residues decomposition on nitrous oxide (N2O) emission, a field study was performed with application of crop residues with different C:N ratios in a bare yellow brown soil at the experimental station of Zhangjiachong at Zigui, China. We set up six experimental treatments: no crop residue (CK), rapeseed cake (RC), potato stalk (PS), rice straw (RS), wheat straw (WS), and corn straw (CS). The carbon (C) to nitrogen (N) ratios of these crop residues were 7.5, 32.9, 40.4, 65.7, and 90.9, respectively. Nitrous oxide fluxes were measured using a static closed chamber method. N2O emissions were significantly enhanced by incorporation of crop residues. Cumulative N2O emissions negatively correlated with C:N ratio (R (2) = 0.9821) of the crop residue, but they were positively correlated with average concentrations of dissolved organic carbon and microbial biomass carbon. Nitrogen emission fraction, calculated as N2O-N emissions originated from the crop residues N, positively correlated with C:N ratio of the residues (P emissions because a significant correlation (P emissions in all treatments except the control. In contrast, a significant relationship between soil moisture and N2O emissions was found in the control only. Furthermore, N2O emission significantly correlated (P carbon and nitrogen contents can significantly alter soil N2O flux rates; and (2) soil biotic as well as abiotic variables are critical in determining soil-atmospheric N2O emissions after crop residue incorporation into soil.

  9. On the Ground or in the Air? A Methodological Experiment on Crop Residue Cover Measurement in Ethiopia.

    Science.gov (United States)

    Kosmowski, Frédéric; Stevenson, James; Campbell, Jeff; Ambel, Alemayehu; Haile Tsegay, Asmelash

    2017-10-01

    Maintaining permanent coverage of the soil using crop residues is an important and commonly recommended practice in conservation agriculture. Measuring this practice is an essential step in improving knowledge about the adoption and impact of conservation agriculture. Different data collection methods can be implemented to capture the field level crop residue coverage for a given plot, each with its own implication on survey budget, implementation speed and respondent and interviewer burden. In this paper, six alternative methods of crop residue coverage measurement are tested among the same sample of rural households in Ethiopia. The relative accuracy of these methods are compared against a benchmark, the line-transect method. The alternative methods compared against the benchmark include: (i) interviewee (respondent) estimation; (ii) enumerator estimation visiting the field; (iii) interviewee with visual-aid without visiting the field; (iv) enumerator with visual-aid visiting the field; (v) field picture collected with a drone and analyzed with image-processing methods and (vi) satellite picture of the field analyzed with remote sensing methods. Results of the methodological experiment show that survey-based methods tend to underestimate field residue cover. When quantitative data on cover are needed, the best estimates are provided by visual-aid protocols. For categorical analysis (i.e., >30% cover or not), visual-aid protocols and remote sensing methods perform equally well. Among survey-based methods, the strongest correlates of measurement errors are total farm size, field size, distance, and slope. Results deliver a ranking of measurement options that can inform survey practitioners and researchers.

  10. On the Ground or in the Air? A Methodological Experiment on Crop Residue Cover Measurement in Ethiopia

    Science.gov (United States)

    Kosmowski, Frédéric; Stevenson, James; Campbell, Jeff; Ambel, Alemayehu; Haile Tsegay, Asmelash

    2017-10-01

    Maintaining permanent coverage of the soil using crop residues is an important and commonly recommended practice in conservation agriculture. Measuring this practice is an essential step in improving knowledge about the adoption and impact of conservation agriculture. Different data collection methods can be implemented to capture the field level crop residue coverage for a given plot, each with its own implication on survey budget, implementation speed and respondent and interviewer burden. In this paper, six alternative methods of crop residue coverage measurement are tested among the same sample of rural households in Ethiopia. The relative accuracy of these methods are compared against a benchmark, the line-transect method. The alternative methods compared against the benchmark include: (i) interviewee (respondent) estimation; (ii) enumerator estimation visiting the field; (iii) interviewee with visual-aid without visiting the field; (iv) enumerator with visual-aid visiting the field; (v) field picture collected with a drone and analyzed with image-processing methods and (vi) satellite picture of the field analyzed with remote sensing methods. Results of the methodological experiment show that survey-based methods tend to underestimate field residue cover. When quantitative data on cover are needed, the best estimates are provided by visual-aid protocols. For categorical analysis (i.e., >30% cover or not), visual-aid protocols and remote sensing methods perform equally well. Among survey-based methods, the strongest correlates of measurement errors are total farm size, field size, distance, and slope. Results deliver a ranking of measurement options that can inform survey practitioners and researchers.

  11. BIOGAS PRODUCTION FROM CATCH CROPS

    DEFF Research Database (Denmark)

    Molinuevo-Salces, Beatriz; Larsen, Søren U.; Ahring, Birgitte Kiær

    2014-01-01

    -substrate in manure-based biogas plants and the profit obtained from the sale of biogas barely compensates for the harvest costs. A new agricultural strategy to harvest catch crops together with the residual straw of the main crop was investigated to increase the biomass and thereby the methane yield per hectare......Catch crop cultivation combined with its use for biogas production would increase renewable energy production in the form of methane, without interfering with the production of food and fodder crops. The low biomass yield of catch crops is the main limiting factor for using these crops as co...... biomass. Leaving the straw on the field until harvest of the catch crop in the autumn could benefit biogas production due to the organic matter degradation of the straw taking place on the field during the autumn months. This new agricultural strategy may be a good alternative to achieve economically...

  12. Detection of pyridaben residue levels in hot pepper fruit and leaves by liquid chromatography-tandem mass spectrometry: effect of household processes.

    Science.gov (United States)

    Kim, Sung-Woo; Abd El-Aty, A M; Rahman, Md Musfiqur; Choi, Jeong-Heui; Choi, Ok-Ja; Rhee, Gyu-Seek; Chang, Moon-Ik; Kim, Heejung; Abid, Morad D N; Shin, Sung Chul; Shim, Jae-Han

    2015-07-01

    Following quick, easy, cheap, effective, rugged and safe (QuEChERS) and LC/MS/MS analysis, pyridaben residual levels were determined in unprocessed and processed hot pepper fruit and leaves. The linearities were satisfactory with determination coefficients (R(2)) in excess of 0.995 in processed and unprocessed pepper fruit and leaves. Recoveries at various concentrations were 79.9-105.1% with relative standard deviations ≤15%. The limits of quantitation of 0.003-0.012 mg/kg were very low compared with the maximum residue limits (2-5 mg/kg) set by the Ministry of Food and Drug Safety, Republic of Korea. The effects of various household processes, including washing, blanching, frying and drying under different conditions (water volume, blanching time and temperature) on residual concentrations were evaluated. Both washing and blanching (in combination with high water volume and time factor) significantly reduced residue levels in hot pepper fruit and leaves compared with other processes. In sum, the developed method was satisfactory and could be used to accurately detect residues in unprocessed and processed pepper fruit and leaves. It is recommended that pepper fruit/leaves be blanched after washing before being consumed to protect consumers from the negative health effects of detected pesticide residues. Copyright © 2014 John Wiley & Sons, Ltd.

  13. Tracking residual organochlorine pesticides (OCPs) in green, herbal, and black tea leaves and infusions of commercially available tea products marketed in Poland.

    Science.gov (United States)

    Witczak, Agata; Abdel-Gawad, Hassan; Zalesak, Michal; Pohoryło, Anna

    2018-03-01

    The content of residual organochlorine pesticides (OCPs) was examined in green, herbal, and black tea leaves as well as in their infusions prepared from tea products marketed in the main supermarkets in Poland. It was found that the detected mean levels of organochlorine residues in tea leaves ranged from tea occurred in the highest concentrations. Among dichlorodiphenyltrichloroethane (DDT) metabolites the highest level of p,p'DDT (1.96 ng g -1 dw) was in green tea samples. The transfer of OCPs from tea leaves to brew was investigated. The present study revealed that during the infusion process, a significant percentage of the residues, particularly pesticides with high water solubility, were transferred to the infusions. The obtained results show that the percentage transfer of each pesticides from tea to the tea infusions ranged from 6.74% (heptachlor) to 86.6% (endrin). The detected residues were below current MRLs for these pesticides.

  14. Residual N effect of long-term applications of cattle slurry using winter wheat as test crop

    DEFF Research Database (Denmark)

    Suarez, Alfonso; Thomsen, Ingrid Kaag; Rasmussen, Jim

    2018-01-01

    ) as reference treatments. In the test years, the customary nutrient treatments were withheld and each plot divided into six subplots randomly allocated increasing rates of mineral fertilizer N (0–250 kg N ha−1). The winter wheat yielded more in the first test year due to crop rotational effects and more benign...... climatic conditions, substantiating that more test years are needed when estimating residual N effects. The residual value of N added previously with NPK was negligible. In the first year, grain yields at N optimum were similar for NPK and SLU, but the amount of fertilizer N needed to reach optimum yield...... in cattle slurry (50, 100 and 150 kg total-N ha−1 termed ½, 1 and 1½ SLU), we estimated the residual N value over two consecutive growth periods (2014/2015 and 2015/2016). We used winter wheat as test crop and soils with a history of mineral fertilizers only (1 PK (no N)) and 1 NPK (100 kg N ha−1...

  15. Influence of gypsum and farmyard manure on fertilizer zinc uptake by wheat and its residual effect on succeeding rice and wheat crops in a sodic soil

    International Nuclear Information System (INIS)

    Sachdev, P.; Deb, D.L.

    1990-01-01

    Greenhouse experiments were conducted to evaluate the effectiveness of gypsum and FYM on a sodic soil on fertilizer Zn uptake by wheat and residual effect on succeeding crops of rice and wheat. Application of FYM significantly increased the yield of first wheat crop as well as the yield of subsequent rice and wheat crops, but gypsum showed significant effect only on rice. FYM application also resulted in an increase in Zn content of all the three crops. Utilisation of the fertilizer Zn by the first crop of wheat ranged between 0.30 to 0.54 per cent while succeeding crop of rice utilised 1.00 to 1.25 per cent of the applied Zn. Application of gypsum to the first crop did not influence the fertilizer Zn uptake by wheat, rice and wheat, however, it significantly reduced the soil pH and increased the available Zn content in soil. (author). 15 refs., 6 tabs

  16. Exchangeable basic cations and nitrogen distribution in soil as affected by crop residues and nitrogen

    Directory of Open Access Journals (Sweden)

    Ciro Antonio Rosolem

    2011-06-01

    Full Text Available In this work, a greenhouse experiment was conducted to study the effects of N fertilization and residues of pearl millet, black oats and oilseed radish on pH and Ca, Mg, K, NO3-, and NH4+ distribution within the profile of a Distroferric Red Latosol. The equivalent of 8 t ha-1 of plant residues were placed on soil surface. Lime was applied on the soil surface and nitrogen was applied over the straw at 0, 50, 100, and 150 mg kg-1, as ammonium nitrate. Corn was grown for 57 days. Calcium contents and pH in the soil profile were decreased by Pearl millet residue, while black oat and oilseed radish increased Ca contents and these effects are not related with Ca contents in residue tissue. However, the presence of plant residues increased nitrate, ammonium, and potassium contents in the deeper layers of the pots.

  17. Long Term Sugarcane Crop Residue Retention Offers Limited Potential to Reduce Nitrogen Fertilizer Rates in Australian Wet Tropical Environments.

    Science.gov (United States)

    Meier, Elizabeth A; Thorburn, Peter J

    2016-01-01

    The warming of world climate systems is driving interest in the mitigation of greenhouse gas (GHG) emissions. In the agricultural sector, practices that mitigate GHG emissions include those that (1) reduce emissions [e.g., those that reduce nitrous oxide (N2O) emissions by avoiding excess nitrogen (N) fertilizer application], and (2) increase soil organic carbon (SOC) stocks (e.g., by retaining instead of burning crop residues). Sugarcane is a globally important crop that can have substantial inputs of N fertilizer and which produces large amounts of crop residues ('trash'). Management of N fertilizer and trash affects soil carbon and nitrogen cycling, and hence GHG emissions. Trash has historically been burned at harvest, but increasingly is being retained on the soil surface as a 'trash blanket' in many countries. The potential for trash retention to alter N fertilizer requirements and sequester SOC was investigated in this study. The APSIM model was calibrated with data from field and laboratory studies of trash decomposition in the wet tropics of northern Australia. APSIM was then validated against four independent data sets, before simulating location × soil × fertilizer × trash management scenarios. Soil carbon increased in trash blanketed soils relative to SOC in soils with burnt trash. However, further increases in SOC for the study region may be limited because the SOC in trash blanketed soils could be approaching equilibrium; future GHG mitigation efforts in this region should therefore focus on N fertilizer management. Simulated N fertilizer rates were able to be reduced from conventional rates regardless of trash management, because of low yield potential in the wet tropics. For crops subjected to continuous trash blanketing, there was substantial immobilization of N in decomposing trash so conventional N fertilizer rates were required for up to 24 years after trash blanketing commenced. After this period, there was potential to reduce N fertilizer

  18. Long term sugarcane crop residue retention offers limited potential to reduce nitrogen fertilizer rates in Australian wet tropical environments

    Directory of Open Access Journals (Sweden)

    Elizabeth Anne Meier

    2016-07-01

    Full Text Available The warming of world climate systems is driving interest in the mitigation of greenhouse gas (GHG emissions. In the agricultural sector, practices that mitigate GHG emissions include those that (1 reduce emissions (e.g. those that reduce nitrous oxide (N2O emissions by avoiding excess nitrogen (N fertilizer application, and (2 increase soil organic carbon (SOC stocks (e.g. by retaining instead of burning crop residues. Sugarcane is a globally important crop that can have substantial inputs of N fertilizer and which produces large amounts of crop residues (‘trash’. Management of N fertilizer and trash affects soil carbon and nitrogen cycling, and hence GHG emissions. Trash has historically been burned at harvest, but increasingly is being retained on the soil surface as a ‘trash blanket’ in many countries. The potential for trash retention to alter N fertilizer requirements and sequester SOC was investigated in this study. The APSIM model was calibrated with data from field and laboratory studies of trash decomposition in the wet tropics of northern Australia. APSIM was then validated against four independent data sets, before simulating location  soil  fertilizer  trash management scenarios. Soil carbon increased in trash blanketed soils relative to SOC in soils with burnt trash. However, further increases in SOC for the study region may be limited because the SOC in trash blanketed soils could be approaching equilibrium; future GHG mitigation efforts in this region should therefore focus on N fertilizer management. Simulated N fertilizer rates were able to be reduced from conventional rates regardless of trash management, because of low yield potential in the wet tropics. For crops subjected to continuous trash blanketing, there was substantial immobilization of N in decomposing trash so conventional N fertilizer rates were required for up to 24 yr after trash blanketing commenced. After this period, there was potential to

  19. Controle de plantas daninhas em milho em função de quantidades de palha de nabo forrageiro Weed control in corn as a function of amount of turnip crop residue

    Directory of Open Access Journals (Sweden)

    M.A. Rizzardi

    2006-06-01

    Full Text Available Objetivou-se com este experimento avaliar a influência da quantidade de palha de nabo forrageiro (Raphanus sativus var. oleiferus no controle de plantas daninhas em milho. O delineamento experimental foi o de parcelas subdivididas, em blocos casualizados, com quatro repetições. Os tratamentos constaram das quantidades de 0, 6 e 9 t ha-1 de palha de nabo forrageiro, além do pousio, dispostas na parcela principal e, ainda, de seis momentos de controle de plantas daninhas (milho com 1, 2, 4, 5, 6 e 7 folhas, mais duas testemunhas (sem a presença de plantas daninhas e sem o controle destas, dispostos nas subparcelas. Houve interação de quantidades de palha e momentos de controle em relação ao grau de controle de plantas daninhas; o melhor momento ocorreu entre os estádios de duas a quatro folhas do milho. Na ausência de controle químico, o rendimento de grãos de milho foi superior no tratamento com 9 t ha-1 de palha de nabo forrageiro. O controle químico não proporcionou aumento significativo no rendimento de grãos do milho quando a quantidade de palha de nabo forrageiro foi de 9 t ha-1.The objective of this study was to evaluate the effect of the amount of turnip (Raphanus sativus var. oleiferus crop residue on weed control in corn. The experimental design was a split-plot, in randomized blocks, with four replications. The treatments tested were 0, 6, and 9 t ha-1 of turnip crop residues, fallow period (the amount of residues was equivalent to the amount of natural vegetation residues, arranged as main plots, and six weed control periods (corn plants with 1, 2, 4, 5, 6, and 7 developed leaves, besides two controls (one without weeds and another without weed control, arranged as subplots. Interactions occurred between residue amounts and control periods in relation to the degree of weed control. The best control period was achieved when the corn plants presented from 2 to 4 developed leaves. Corn grain yield was higher in the control

  20. Morphology, composition, and mixing state of primary particles from combustion sources - crop residue, wood, and solid waste.

    Science.gov (United States)

    Liu, Lei; Kong, Shaofei; Zhang, Yinxiao; Wang, Yuanyuan; Xu, Liang; Yan, Qin; Lingaswamy, A P; Shi, Zongbo; Lv, Senlin; Niu, Hongya; Shao, Longyi; Hu, Min; Zhang, Daizhou; Chen, Jianmin; Zhang, Xiaoye; Li, Weijun

    2017-07-11

    Morphology, composition, and mixing state of individual particles emitted from crop residue, wood, and solid waste combustion in a residential stove were analyzed using transmission electron microscopy (TEM). Our study showed that particles from crop residue and apple wood combustion were mainly organic matter (OM) in smoldering phase, whereas soot-OM internally mixed with K in flaming phase. Wild grass combustion in flaming phase released some Cl-rich-OM/soot particles and cardboard combustion released OM and S-rich particles. Interestingly, particles from hardwood (pear wood and bamboo) and softwood (cypress and pine wood) combustion were mainly soot and OM in the flaming phase, respectively. The combustion of foam boxes, rubber tires, and plastic bottles/bags in the flaming phase released large amounts of soot internally mixed with a small amount of OM, whereas the combustion of printed circuit boards and copper-core cables emitted large amounts of OM with Br-rich inclusions. In addition, the printed circuit board combustion released toxic metals containing Pb, Zn, Sn, and Sb. The results are important to document properties of primary particles from combustion sources, which can be used to trace the sources of ambient particles and to know their potential impacts in human health and radiative forcing in the air.

  1. Evaluation of crop residues on potassium kinetics in an acid soil and potassium use efficiency in potato-garlic sequence using tracer 86Rb

    International Nuclear Information System (INIS)

    Sud, K.C.

    2005-01-01

    Greenhouse and laboratory studies were conducted on an acid soil in order to evaluate the role of two crop residues i.e. paddy and wheat along with farmyard manure on potassium kinetics and its availability in the potato-garlic sequence using tracer 86 Rb. Under rapid equilibrium, application of crop residues of paddy, wheat straw and FYM were able to enhance soil pH and organic carbon content. In addition, their application helped in enhancing soil K availability indices like water soluble, available and non-exchangeable -K. This was further augmented by the Q/I studies using 86 Rb where application of organic residues helped in lowering the potassium buffering capacity of the soil. Greenhouse study supplemented the results obtained from laboratory study where application of crop residues/FYM were able to improve the potato yield significantly and maintained higher concentration of K in potato leaf at early growth stages. A significant correlation was obtained between leaf K and haulms-K with that of 86 Rb activities in potato leaf at 35 days and 86 Rb absorbed in the haulms, respectively. Residues/ FYM and PK application to potato left sufficient residual effect on succeeding garlic crop. In potato-garlic sequence, K recovery was highest with FYM while N and P recoveries were higher with wheat residues. The nutrient recoveries with PK application followed law of diminishing returns. (author)

  2. Fate of 14C-allylalcohol herbicide in soils and crop residues

    International Nuclear Information System (INIS)

    Scheunert, I.; Vockel, D.; Klein, W.; Korte, F.

    1981-01-01

    Residue disappearance and leaching of 14 C-allylalcohol from different soils were studied in laboratory experiments. Additionally, the uptake of residues by lettuce and carrots was investigated in the greenhouse. In laboratory experiments, residue disappearance and leaching from soils was correlated negatively to the organic matter content. In greenhouse experiments with a sandy loam soil at an application rate normally used in practice, an average of 12.5% of the applied radioactivity was recovered after an eight day interval between application and sowing. Furthermore, an average of 8% (sum in soil and plants) of the applied radioactivity was recovered after lettuce or carrot growing. Uptake of residues was higher by carrots than by lettuce, and higher by lettuce roots than by lettuce tops. No bioaccumulation was observed. The residues in soils and plants were, to a high percent-age, unextractable and, to a smaller extent, fully water-soluble products. Unchanged allylalcohol could not be detected by the analytical methods used

  3. Square baler field test under different sugar cane crop residue conditions

    Energy Technology Data Exchange (ETDEWEB)

    Mello, Arthur Miola de; Ripoli, Tomaz Caetano Cannavan; Gadanha Junior, Casimiro [Escola Superior de Agricultura Luiz de Queiroz (ESALQ-USP), Piracicaba (Brazil). Dept. de Engenharia Rural], E-mail: ammello@esalq.usp.br; Ripoli, Marco Lorezzo Cunali [John Deere, Ribeirao Preto, SP (Brazil)

    2008-07-01

    The energy demand increase of the country allows the sugar cane business sector to be a major player in production and commercialization areas of electric energy using cogeneration powered by bagasse and sugar cane residues. The objective of the study was to evaluate some of the performance parameters of an Express 5040 baler, brand Nogueira, used to collect residues. The tests were conducted in a sugar cane mechanized harvest area. The baler was submitted to three different conditions of residues windrowing: 'in natura', under single and double raking operations. For all treatments soil sampling analyzes were done to find out ground homogeneity conditions were the test took place. The simple raking operation offered better conditions for the machine: Effective Capacity of 8.21 t.{sup h}-{sup 1} and 0.88 ha.h{sup -1}; average bale weight of 22.33 kg (SD=3.58, CV=16.01 %); costs of 7.45 R$.t{sup -1} of baled residue; 0.17 R$.fardo{sup -1} and 69.47 R$.ha{sup -1}. (author)

  4. Crop residue stabilization and application to agricultural and degraded soils: A review.

    Science.gov (United States)

    Medina, Jorge; Monreal, Carlos; Barea, José Miguel; Arriagada, César; Borie, Fernando; Cornejo, Pablo

    2015-08-01

    Agricultural activities produce vast amounts of organic residues including straw, unmarketable or culled fruit and vegetables, post-harvest or post-processing wastes, clippings and residuals from forestry or pruning operations, and animal manure. Improper disposal of these materials may produce undesirable environmental (e.g. odors or insect refuges) and health impacts. On the other hand, agricultural residues are of interest to various industries and sectors of the economy due to their energy content (i.e., for combustion), their potential use as feedstock to produce biofuels and/or fine chemicals, or as a soil amendments for polluted or degraded soils when composted. Our objective is review new biotechnologies that could be used to manage these residues for land application and remediation of contaminated and eroded soils. Bibliographic information is complemented through a comprehensive review of the physico-chemical fundamental mechanisms involved in the transformation and stabilization of organic matter by biotic and abiotic soil components. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Barriers and drivers towards the incorporation of crop residue in the soil. Analysis of Italian farmers’ opinion with the theory of planned behaviour

    Directory of Open Access Journals (Sweden)

    Luca Bechini

    2015-12-01

    Full Text Available Despite the benefits arising from incorporating crop residue in the soil, some farmers decide to burn or sell it. The objective of the work described in this paper was to quantify the adoption of crop residue incorporation by Italian farmers, and to identify the barriers and drivers that they perceive towards this agricultural management practice. We applied a behavioural approach, based on the theory of planned behaviour. In agriculture, this theory can be used to study individual farmer beliefs to understand the intention to adopt agricultural management practices. Based on preliminary semi-structured interviews with 24 farmers, we have prepared and disseminated a structured questionnaire in dairy farms in the plain of northern Italy, in arable farms in the plain of northern, central, and southern Italy, and in arable farms in the hill of central and southern Italy. The questionnaire contained questions to reveal subjective beliefs of the farmers on the outcomes of incorporating crop residue, and on the referents and control factors that might influence adoption. We have received 315 filled questionnaires from 16 regions and 54 provinces. The survey has identified major drivers and barriers towards the incorporation of crop residue in the soil. The main drivers were the expected improvement of soil quality (higher soil organic matter, improved structure and fertility, the expected increase of grain protein concentration in the following wheat crop, the availability of adequate machinery, the prohibition of burning crop residue, and the knowledge that incorporation is important (which emphasizes the importance of an effective advisory service. The main barriers were the costs of incorporation, the need to increase the use of nitrogen fertiliser when straw is incorporated, and the problems to sow the following crop in the presence of residue. While on the basis of the preliminary interviews we expected that the possibility to sell the straw and

  6. Utilization of residual biochar produced from the pyrolysis of energy crops for soil enrichment

    Energy Technology Data Exchange (ETDEWEB)

    Pilon, G.; Lavoie, J.M. [Sherbrooke Univ., Sherbrooke, PQ (Canada). Dept. of Chemical Engineering and Biotechnology

    2010-07-01

    Although national and international interest in the use of energy crops for the production of biofuels is increasing, it is understood that measures must be taken to ensure that the production and transportation of these energy crops does not require more energy than they provide and that the soil should not be left uncovered so as not to reduce its organic content and nutrients. In response, concerns regarding soil fertilization have increased. A technique for biomass preconversion known as pyrolysis-torrefaction involves the production of char and bio-oil from biomass. This processing method is gaining interest because the char may be useful for many applications such as a fuel, soil conditioner or carbon sequestration. An appropriate distribution of biochar applications could be potentially beneficial for the sustainability of biomass use in the imminent biomarket. In this study, biochar produced from switchgrass was prepared and characterized to verify its potential as a soil enhancer and its potential as a solid fuel. The biochar was prepared under varying reacting conditions using custom-made bench scale, batch-type fixed bed pyrolysis-torrefaction reactor. Volatiles were released by varying the residence times.

  7. Storage stability of screwpress-extracted oils and residual meals from CELSS candidate oilseed crops

    Science.gov (United States)

    Stephens, S. D.; Watkins, B. A.; Nielsen, S. S.

    1997-01-01

    The efficacy of using screwpress extraction for oil was studied with three Controlled Ecological Life-Support System (CELSS) candidate oilseed crops (soybean, peanut, and canola), since use of volatile organic solvents for oil extraction likely would be impractical in a closed system. Low oil yields from initial work indicated that a modification of the process is necessary to increase extraction efficiency. The extracted oil from each crop was tested for stability and sensory characteristics. When stored at 23 degC, canola oil and meal were least stable to oxidative rancidity, whereas peanut oil and meal were least stable to hydrolytic rancidity. When stored at 65 degC, soybean oil and canola meal were least stable to oxidative rancidity, whereas peanut oil and meal were least stable to hydrolytic rancidity. Sensory evaluation of the extracted oils used in bread and salad dressing indicated that flavor, odor intensity, acceptability, and overall preference may be of concern for screwpress-extracted canola oil when it is used in an unrefined form. Overall results with screwpress-extracted crude oils indicated that soybean oil may be more stable and acceptable than canola or peanut under typical storage conditions.

  8. Earthworms and Plant Residues Modify Nematodes in Tropical Cropping Soils (Madagascar: A Mesocosm Experiment

    Directory of Open Access Journals (Sweden)

    Cécile Villenave

    2010-01-01

    Full Text Available Free-living nematodes present several characteristics that have led to their use as bioindicators of soil quality. Analyzing the structure of nematofauna is a pertinent way to understand soil biological processes. Earthworms play an important role in soil biological functioning and organic matter dynamics. Their effects on soil nematofauna have seldom been studied. We studied the effect of the tropical endogeic earthworm, Pontoscolex corethrurus, on nematode community structure in a 5-month field mesocosm experiment conducted in Madagascar. Ten different treatments with or without earthworms and with or without organic residues (rice, soybean were compared. Organic residues were applied on the soil surface or mixed with the soil. The abundance of nematodes (bacterial and fungal feeders was higher in presence of P. corethrurus than in their absence. The type of plant residues as well as their localisation had significant effects on the abundance and composition of soil nematodes. The analysis of nematode community structure showed that earthworm activity led to an overall activation of the microbial compartment without specific stimulation of the bacterial or fungal compartment.

  9. Earthworms and Plant Residues Modify Nematodes in Tropical Cropping Soils (Madagascar): A Mesocosm Experiment

    International Nuclear Information System (INIS)

    Villenave, C.; Kichenin, E.; Djigal, D.; Blanchart, E.; Rabary, B.; Djigal, D.

    2010-01-01

    Free-living nematodes present several characteristics that have led to their use as bio indicators of soil quality. Analyzing the structure of nematofauna is a pertinent way to understand soil biological processes. Earthworms play an important role in soil biological functioning and organic matter dynamics. Their effects on soil nematofauna have seldom been studied. We studied the effect of the tropical endogeic earthworm, Pontoscolex corethrurus, on nematode community structure in a 5-month field mesocosm experiment conducted in Madagascar. Ten different treatments with or without earthworms and with or without organic residues (rice, soybean) were compared. Organic residues were applied on the soil surface or mixed with the soil. The abundance of nematodes (bacterial and fungal feeders) was higher in presence of P. corethrurus than in their absence. The type of plant residues as well as their localisation had significant effects on the abundance and composition of soil nematodes. The analysis of nematode community structure showed that earthworm activity led to an overall activation of the microbial compartment without specific stimulation of the bacterial or fungal compartment.

  10. Nitrous Oxide Emission and Denitrifier Abundance in Two Agricultural Soils Amended with Crop Residues and Urea in the North China Plain.

    Directory of Open Access Journals (Sweden)

    Jianmin Gao

    Full Text Available The application of crop residues combined with Nitrogen (N fertilizer has been broadly adopted in China. Crop residue amendments can provide readily available C and N, as well as other nutrients to agricultural soils, but also intensify the N fixation, further affecting N2O emissions. N2O pulses are obviously driven by rainfall, irrigation and fertilization. Fertilization before rainfall or followed by flooding irrigation is a general management practice for a wheat-maize rotation in the North China Plain. Yet, little is known on the impacts of crop residues combined with N fertilizer application on N2O emission under high soil moisture content. A laboratory incubation experiment was conducted to investigate the effects of two crop residue amendments (maize and wheat, individually or in combination with N fertilizer, on N2O emissions and denitrifier abundance in two main agricultural soils (one is an alluvial soil, pH 8.55, belongs to Ochri-Aquic Cambosols, OAC, the other is a lime concretion black soil, pH 6.61, belongs to Hapli-Aquic Vertosols, HAV under 80% WFPS (the water filled pore space in the North China Plain. Each type soil contains seven treatments: a control with no N fertilizer application (CK, N0, 200 kg N ha-1 (N200, 250 kg N ha-1 (N250, maize residue plus N200 (MN200, maize residue plus N250 (MN250, wheat residue plus N200 (WN200 and wheat residue plus N250 (WN250. Results showed that, in the HAV soil, MN250 and WN250 increased the cumulative N2O emissions by 60% and 30% compared with N250 treatment, respectively, but MN200 and WN200 decreased the cumulative N2O emissions by 20% and 50% compared with N200. In the OAC soil, compared with N200 or N250, WN200 and WN250 increased the cumulative N2O emission by 40%-50%, but MN200 and MN250 decreased the cumulative N2O emission by 10%-20%. Compared with CK, addition of crop residue or N fertilizer resulted in significant increases in N2O emissions in both soils. The cumulative N2O

  11. Bioenergy from crops and biomass residues: a consequential life-cycle assessment including land-use changes

    DEFF Research Database (Denmark)

    Tonini, Davide; Astrup, Thomas Fruergaard

    Biofuels are promising means to reduce fossil fuel depletion and mitigate greenhouse-gas (GHG) emissions. However, recent studies questioned the environmental benefits earlier attributed to biofuels, when these involve land-use changes (direct/indirect, i.e., dLUC/iLUC) (1-5). Yet, second...... to represent the actual environmental impacts. This study quantified the GHG emissions associated with a number of scenarios involving bioenergy production (as combined-heat-and-power, heating, and transport biofuel) from energy crops, industrial/agricultural residues, algae, and the organic fraction...... of municipal solid waste. Four conversion pathways were considered: combustion, fermentation-to-ethanol, fermentation-to-biogas, and thermal gasification. A total of 80 bioenergy scenarios were assessed. Consequential life-cycle assessment (CLCA) was used to quantify the environmental impacts. CLCA aimed...

  12. Long-term performance of anaerobic digestion for crop residues containing heavy metals and response of microbial communities.

    Science.gov (United States)

    Lee, Jongkeun; Kim, Joonrae Roger; Jeong, Seulki; Cho, Jinwoo; Kim, Jae Young

    2017-01-01

    In order to investigate the long-term stability on the performance of the anaerobic digestion process, a laboratory-scale continuous stirred-tank reactor (CSTR) was operated for 1100 days with sunflower harvested in a heavy metal contaminated site. Changes of microbial communities during digestion were identified using pyrosequencing. According to the results, soluble heavy metal concentrations were lower than the reported inhibitory level and the reactor performance remained stable up to OLR of 2.0g-VS/L/day at HRT of 20days. Microbial communities commonly found in anaerobic digestion for cellulosic biomass were observed and stably established with respect to the substrate. Thus, the balance of microbial metabolism was maintained appropriately and anaerobic digestion seems to be feasible for disposal of heavy metal-containing crop residues from phytoremediation sites. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Phosphorus fractionation and crop performance on an alfisol ...

    African Journals Online (AJOL)

    The effects of Sokoto phosphate rock (PR) and plant residues on soil phosphorus (P) fractions and crop performance was studied in the field on an alfisol in the derived savanna of southwestern Nigeria. The plant residues studied were leaves of Dactyladenia barteri, Flemingia macrophylla, Gliricidia sepium, Leucaena ...

  14. [Multi-residue method for screening of pesticides in crops by liquid chromatography with tandem mass spectrometry].

    Science.gov (United States)

    Tanizawa, Haruna; Shima, Mikie; Ikehara, Chieko; Kobata, Masakazu; Sato, Motoaki

    2005-10-01

    A simple and rapid method was developed for the screening of 82 pesticides/metabolites in a wide variety of crops, using solid-phase extraction and liquid chromatography with tandem mass spectrometry (LC/MS/MS). After extraction with methanol, the filtered extracts were made up to 100 mL and a 2 mL aliquot was subjected to solid-phase extraction. Co-extractives were removed with a C18 mini-column, while pesticides were retained on 3 kinds of mini-columns (HLB, SAX, activated carbon), and then eluted with acetonitrile. Analysis was performed by LC/MS/MS, and MS acquisition parameters were established in positive and negative ESI modes. The utility of the method was demonstrated by the analysis of 6 crops (carrot, cabbage, onion, spinach, lemon, brown rice) and one mixed vegetable juice. Of 82 compounds tested, 75 in carrot and 62 in lemon were obtained with recoveries ranging from 70-120%. For all samples tested, 75 compounds could be obtained with recoveries of over 50%, and the detection limits of most compounds were lower than 0.01 microg/g. This method provides acceptable performance for analysis of these 75 compounds. Further, by using aliquots of the extracts with small-scale mini-columns, purified samples could be obtained. This proposed method with small matrix effects, is effective and suitable for screening of multiple residual pesticides by using LC/MS/MS.

  15. Nitrosospira sp. Govern Nitrous Oxide Emissions in a Tropical Soil Amended With Residues of Bioenergy Crop

    Directory of Open Access Journals (Sweden)

    Késia S. Lourenço

    2018-04-01

    Full Text Available Organic vinasse, a residue produced during bioethanol production, increases nitrous oxide (N2O emissions when applied with inorganic nitrogen (N fertilizer in soil. The present study investigated the role of the ammonia-oxidizing bacteria (AOB community on the N2O emissions in soils amended with organic vinasse (CV: concentrated and V: non-concentrated plus inorganic N fertilizer. Soil samples and N2O emissions were evaluated at 11, 19, and 45 days after fertilizer application, and the bacterial and archaea gene (amoA encoding the ammonia monooxygenase enzyme, bacterial denitrifier (nirK, nirS, and nosZ genes and total bacteria were quantified by real time PCR. We also employed a deep amoA amplicon sequencing approach to evaluate the effect of treatment on the community structure and diversity of the soil AOB community. Both vinasse types applied with inorganic N application increased the total N2O emissions and the abundance of AOB. Nitrosospira sp. was the dominant AOB in the soil and was correlated with N2O emissions. However, the diversity and the community structure of AOB did not change with vinasse and inorganic N fertilizer amendment. The results highlight the importance of residues and fertilizer management in sustainable agriculture and can be used as a reference and an input tool to determine good management practices for organic fertilization.

  16. High quality residues from cover crops favor changes in microbial community and enhance C and N sequestration

    Directory of Open Access Journals (Sweden)

    Ileana Frasier

    2016-04-01

    Full Text Available The objective of the study was to evaluate the effect of a change in management on the soil microbial community and C sequestration. We conducted a 3-year field study in La Pampa (Argentina with rotation of sorghum (Sorghum bicolor in zero tillage alternating with rye (Secale cereale and vetch (Vicia villosa ssp. dasycarpa. Soil was sampled once a year at two depths. Soil organic matter fractions, dissolved organic matter, microbial biomass (MBC and community composition (DNA extraction, qPCR, and phospholipid FAME profiles were determined. Litter, aerial- and root biomass were collected and all material was analyzed for C and N. Results showed a rapid response of microbial biomass to a bacterial dominance independent of residue quality. Vetch had the highest diversity index, while the fertilized treatment had the lowest one. Vetch–sorghum rotation with high N mineralization rates and diverse microbial community sequestered more C and N in stable soil organic matter fractions than no-till sorghum alone or with rye, which had lower N turnover rates. These results reaffirm the importance of enhanced soil biodiversity for maintaining soil ecosystem functioning and services. The supply of high amounts of N-rich residues as provided by grass–legume cover crops could fulfill this objective.

  17. Effects of tropical ecosystem engineers on soil quality and crop performance under different tillage and residue management

    Science.gov (United States)

    Pulleman, Mirjam; Paul, Birthe; Fredrick, Ayuke; Hoogmoed, Marianne; Hurisso, Tunsisa; Ndabamenye, Telesphore; Saidou, Koala; Terano, Yusuke; Six, Johan; Vanlauwe, Bernard

    2014-05-01

    Feeding a future global population of 9 billion will require a 70-100% increase in food production, resulting in unprecedented challenges for agriculture and natural resources, especially in Sub-saharan Africa (SSA). Agricultural practices that contribute to sustainable intensification build on beneficial biological interactions and ecosystem services. Termites are the dominant soil ecosystem engineers in arid to sub-humid tropical agro-ecosystems. Various studies have demonstrated the potential benefits of termites for rehabilitation of degraded and crusted soils and plant growth in semi-arid and arid natural ecosystems. However, the contribution of termites to agricultural productivity has hardly been experimentally investigated, and their role in Conservation Agriculture (CA) systems remains especially unclear. Therefore, this study aimed to quantify the effects of termites and ants on soil physical quality and crop productivity under different tillage and residue management systems in the medium term. A randomized block trial was set up in sub-humid Western Kenya in 2003. Treatments included a factorial combination of residue retention and removal (+R/-R) and conventional and reduced tillage (+T/-T) under a maize (Zea mays L.) and soybean (Glyxine max. L.) rotation. A macrofauna exclusion experiment was superimposed in 2005 as a split-plot factor (exclusion +ins; inclusion -ins) by regular applications of pesticides (Dursban and Endosulfan) in half of the plots. Macrofauna abundance and diversity, soil aggregate fractions, soil carbon contents and crop yields were measured between 2005 and 2012 at 0-15 cm and 15-30 cm soil depths. Termites were the most important macrofauna species, constituting between 48-63% of all soil biota, while ants were 13-34%, whereas earthworms were present in very low numbers. Insecticide application was effective in reducing termites (85-56% exclusion efficacy) and earthworms (87%), and less so ants (49-81%) at 0-15 cm soil depth

  18. Effectiveness of the GAEC cross-compliance standard management of stubble and crop residues in the maintenance of adequate contents of soil organic carbon

    Directory of Open Access Journals (Sweden)

    Domenico Ventrella

    2011-08-01

    Full Text Available Several studies carried out on the effects of stubble and crop residue incorporation have shown positive effects on chemical-physical soil characteristics. However, not all studies agree on the extent of soil organic matter increase which derives from this process, as this effect is strongly affected by other factors: the pedo-climatic features of the area in which the study is carried out, the type of crop residue incorporation and the agronomical management adopted to improve the decomposition of the incorporated fresh organic material. The burning of stubble and straw is common in the areas where cereals are traditionally grown. The adoption of this method is based on different technical and work-related factors, which become less important when taking into account the impact on the local environment and soil. A research is currently carried out at the CRA-SCA experimental farm in Foggia (Southern Italy on the effects of either residues incorporation or burning on the chemical-physical characteristics of the soil and on the wheat yield performance since 1977. This experiment allows for a comparison among the effects of burning, the simple incorporation of stubble and crop residues and incorporation carried out with some agronomical techniques (such as the distribution of increasing amounts of nitrogen on crop residue before incorporation and the simulation of rain (50 mm on the decomposition of organic material. The objective of the study was to understand the effect of the different residues management practices on soil chemical properties after 32 years of experimentation. The simple incorporation of straw and stubble showed a slight increase in organic soil matter of 0.7% with respect to burning. The best results for soil organic carbon and soil quality were obtained when residual incorporation included a treatment with additional mineral nitrogen.

  19. Assessment of Ex-Vitro Anaerobic Digestion Kinetics of Crop Residues Through First Order Exponential Models: Effect of LAG Phase Period and Curve Factor

    Directory of Open Access Journals (Sweden)

    Abdul Razaque Sahito

    2013-04-01

    Full Text Available Kinetic studies of AD (Anaerobic Digestion process are useful to predict the performance of digesters and design appropriate digesters and also helpful in understanding inhibitory mechanisms of biodegradation. The aim of this study was to assess the anaerobic kinetics of crop residues digestion with buffalo dung. Seven crop residues namely, bagasse, banana plant waste, canola straw, cotton stalks, rice straw, sugarcane trash and wheat straw were selected from the field and were analyzed on MC (Moisture Contents, TS (Total Solids and VS (Volatile Solids with standard methods. In present study, three first order exponential models namely exponential model, exponential lag phase model and exponential curve factor model were used to assess the kinetics of the AD process of crop residues and the effect of lag phase and curve factor was analyzed based on statistical hypothesis testing and on information theory. Assessment of kinetics of the AD of crop residues and buffalo dung follows the first order kinetics. Out of the three models, the simple exponential model was the poorest model, while the first order exponential curve factor model is the best fit model. In addition to statistical hypothesis testing, the exponential curve factor model has least value of AIC (Akaike's Information Criterion and can generate methane production data more accurately. Furthermore, there is an inverse linear relationship between the lag phase period and the curve factor.

  20. Assessment of ex-vitro anaerobic digestion kinetics of crop residues through first order exponential models: effect of lag phase period and curve factor

    International Nuclear Information System (INIS)

    Sahito, A.R.; Brohi, K.M.

    2013-01-01

    Kinetic studies of AD (Anaerobic Digestion) process are useful to predict the performance of digesters and design appropriate digesters and also helpful in understanding inhibitory mechanisms of biodegradation. The aim of this study was to assess the anaerobic kinetics of crop residues digestion with buffalo dung. Seven crop residues namely, bagasse, banana plant waste, canola straw, cotton stalks, rice straw, sugarcane trash and wheat straw were selected from the field and were analyzed on MC (Moisture Contents), TS (Total Solids) and VS (Volatile Solids) with standard methods. In present study, three first order exponential models namely exponential model, exponential lag phase model and exponential curve factor model were used to assess the kinetics of the AD process of crop residues and the effect of lag phase and curve factor was analyzed based on statistical hypothesis testing and on information theory. Assessment of kinetics of the AD of crop residues and buffalo dung follows the first order kinetics. Out of the three models, the simple exponential model was the poorest model, while the first order exponential curve factor model is the best fit model. In addition to statistical hypothesis testing, the exponential curve factor model has least value of AIC (Akaike's Information Criterion) and can generate methane production data more accurately. Furthermore, there is an inverse linear relationship between the lag phase period and the curve factor. (author)

  1. Municipal household waste used as complement material for composting chicken manure and crop residues

    Directory of Open Access Journals (Sweden)

    Guillaume L. Amadji

    2013-06-01

    Full Text Available There are few organic materials available as agricultural soil amendment because their low chemical content means that large quantities are required. In order to improve the availability of raw materials for composting, as well as the quality of the compost produced, municipal solid waste (MW was added to cotton-seed residue (CSR and to the association of CSR with chicken manure (M in different weight/weight (MW/added materials ratios of 5:1 and 2:1. Aerobic composting was processed and compost yield was determined, as well as compost particle size and pH. Also, the compost bulk density and its water holding capacity were determined as well as contents of total nitrogen, carbon, phosphorus, calcium (Ca, magnesium and heavy metals. According to its pH and carbon/nitrogen ratio values, the municipal waste of Cotonou was judged to be a good raw material for composting in order to improve availability of the organic source of nutrients. The composts produced with MW+M+CSR had the highest potential for amending Ferralsols, especially with a mixture of 2:1 (200 kg MW+100 kg M+100 kg CSR that could be applied at 10 t ha–1. However, further improvement in composting methods was suggested to increase Ca++ and reduce mercury contents, respectively. Moreover, potassium balance should be improved in the produced compost.

  2. Carcass characteristics and tissue composition of commercial cuts of lambs fed with banana crop residues

    Directory of Open Access Journals (Sweden)

    Tânia Dayana do Carmo

    2016-02-01

    Full Text Available The aim of this study was to evaluate the effect of substitution of Cynodon hay with banana plantation residue hay on the carcass characteristics and tissue composition of commercial cuts of feedlot Santa Inês lambs. Twenty-five whole lambs were used, with an average age of five months and an initial live weight of 26.95 kg (± 1.5, distributed in a completely randomized design with five treatments (1 = 40% Cynodon spp. hay + 60% concentrate; 2 = 20% banana leaf hay + 20% Cynodon spp. hay + 60% concentrate; 3 = 40% banana leaf hay + 60% concentrate; 4 = 20% banana pseudostem hay + 20% Cynodon spp. hay + 60% concentrate; 5 = 40% banana pseudostem hay + 60% concentrate and five repetitions. The lambs were slaughtered on day 69 of the experiment. The variables evaluated were: live weight without fasting (LWWF, live weight post-fasting (LWPF, morphometric measurements in vivo and postmortem, hot and cold carcass weights (HCW, CCW, hot and cold carcass yield (HCY, CCY, biological performance and weight loss by chilling. The carcasses were divided into eight commercial cuts: neck, shoulder, foreshank and hindshank, breast and flank, loin, leg and rack. The leg, shoulder and loin were dissected into muscle, fat and bone. The animals fed on pseudostem hay showed higher LWWF, LWPF, body length, HCW and CCW; however, the HCY, CCY, morphometric measurements and commercial cut weights and yields were not altered by the treatments. The use of pseudostem hay allows for heavier carcasses; however, the use of coproducts changed the characteristics and carcass yield of the assessed commercial cuts.

  3. Digestibility and performance of steers fed low-quality crop residues treated with calcium oxide to partially replace corn in distillers grains finishing diets.

    Science.gov (United States)

    Shreck, A L; Nuttelman, B L; Harding, J L; Griffin, W A; Erickson, G E; Klopfenstein, T J; Cecava, M J

    2015-02-01

    Two studies were conducted to identify methods for treating crop residues to improve digestibility and value in finishing diets based on corn grain and corn wet distillers grain with solubles (WDGS). In Exp. 1, 336 yearling steers (initial BW 356 ± 11.5 kg) were used in a 2 × 3 + 1 factorial arrangement of treatments with 6 pens per treatment. Factors were 3 crop residues (corn cobs, wheat straw, and corn stover) and 2 treatments where crop residues were either fed (20% diet DM) in their native form (NT) or alkaline treated with 5% CaO (DM basis) and hydrated to 50% DM before anaerobic storage (AT). Intakes were not affected by diet (F test; P = 0.30). An interaction between chemical treatment and residue (P 0.10) was observed between control (46% corn; DM basis) and AT (31% corn; DM basis) for DM digestibility (70.7% vs. 73.7%) or OM digestibility (72.1% vs. 77.0%). Dry matter intakes were not different between treated and untreated diets (P = 0.38), but lower (P < 0.01) NDF intake was observed for treated diets (3.1 vs. 3.5 kg/d), suggesting that CaO treatment was effective in solubilizing some carbohydrate. These data suggest that 15% replacement of corn and 10% untreated residue with treated forage result in a nutrient supply of OM similar to that of the control. The improvements in total tract fiber digestibility that occurred when treated forages were fed may have been related to increased digestibility of recoverable NDF and not to increased ruminal pH. Feeding chemically treated crop residues and WDGS is an effective strategy for replacing a portion of corn grain and roughage in feedlot diets.

  4. Prioritizing stream types according to their potential risk to receive crop plant material--A GIS-based procedure to assist in the risk assessment of genetically modified crops and systemic insecticide residues.

    Science.gov (United States)

    Bundschuh, Rebecca; Kuhn, Ulrike; Bundschuh, Mirco; Naegele, Caroline; Elsaesser, David; Schlechtriemen, Ulrich; Oehen, Bernadette; Hilbeck, Angelika; Otto, Mathias; Schulz, Ralf; Hofmann, Frieder

    2016-03-15

    Crop plant residues may enter aquatic ecosystems via wind deposition or surface runoff. In the case of genetically modified crops or crops treated with systemic pesticides, these materials may contain insecticidal Bt toxins or pesticides that potentially affect aquatic life. However, the particular exposure pattern of aquatic ecosystems (i.e., via plant material) is not properly reflected in current risk assessment schemes, which primarily focus on waterborne toxicity and not on plant material as the route of uptake. To assist in risk assessment, the present study proposes a prioritization procedure of stream types based on the freshwater network and crop-specific cultivation data using maize in Germany as a model system. To identify stream types with a high probability of receiving crop materials, we developed a formalized, criteria-based and thus transparent procedure that considers the exposure-related parameters, ecological status--an estimate of the diversity and potential vulnerability of local communities towards anthropogenic stress--and availability of uncontaminated reference sections. By applying the procedure to maize, ten stream types out of 38 are expected to be the most relevant if the ecological effects from plant-incorporated pesticides need to be evaluated. This information is an important first step to identifying habitats within these stream types with a high probability of receiving crop plant material at a more local scale, including accumulation areas. Moreover, the prioritization procedure developed in the present study may support the selection of aquatic species for ecotoxicological testing based on their probability of occurrence in stream types having a higher chance of exposure. Finally, this procedure can be adapted to any geographical region or crop of interest and is, therefore, a valuable tool for a site-specific risk assessment of crop plants carrying systemic pesticides or novel proteins, such as insecticidal Bt toxins, expressed

  5. Grain yield and crop N offtake in response to residual fertilizer N in long-term field experiments

    DEFF Research Database (Denmark)

    Petersen, Jens; Thomsen, Ingrid Kaag; Mattsson, L.

    2010-01-01

    in four long-term (>35 yr) field experiments, we measured the response of barley (grain yield and N offtake at crop maturity) to six rates (0, 30, 60, 90, 120 and 150 kg N/ha) of mineral fertilizer N (Nnew) applied in subplots replacing the customary long-term plot treatments of fertilizer inputs (Nprev......). Rates of Nprev above 50-100 kg N/ha had no consistent effect on the soil N content, but this was up to 20% greater than that in unfertilized treatments. Long-term unfertilized plots should not be used as control to test the residual value of N in modern agriculture with large production potentials....... Although the effect of mineral Nprev on grain yield and N offtake could be substituted by Nnew within a range of previous inputs, the value of Nprev was not eliminated irrespective of Nnew rate. Provided a sufficient supply of plant nutrients other than N, the use-efficiency of Nnew did not change...

  6. Interception of residual nitrate from a calcareous alluvial soil profile on the North China Plain by deep-rooted crops: A {sup 15}N tracer study

    Energy Technology Data Exchange (ETDEWEB)

    Ju, X.T. [Key Laboratory of Plant-Soil Interactions, Ministry of Education, College of Agricultural Resources and Environmental Sciences, China Agricultural University, 2 Yuan Ming Yuan West Road, Hai Dian District, Beijing 100094 (China)]. E-mail: juxt@cau.edu.cn; Gao, Q. [Key Laboratory of Plant-Soil Interactions, Ministry of Education, College of Agricultural Resources and Environmental Sciences, China Agricultural University, 2 Yuan Ming Yuan West Road, Hai Dian District, Beijing 100094 (China); College of Agricultural Resources and Environmental Sciences, Jilin Agricultural University, Changchun 130118 (China); Christie, P. [Key Laboratory of Plant-Soil Interactions, Ministry of Education, College of Agricultural Resources and Environmental Sciences, China Agricultural University, 2 Yuan Ming Yuan West Road, Hai Dian District, Beijing 100094 (China); Agricultural and Environmental Science Department, Queen' s University Belfast, Belfast BT9 5PX (United Kingdom); Zhang, F.S. [Key Laboratory of Plant-Soil Interactions, Ministry of Education, College of Agricultural Resources and Environmental Sciences, China Agricultural University, 2 Yuan Ming Yuan West Road, Hai Dian District, Beijing 100094 (China)

    2007-03-15

    {sup 15}N-labeled nitrate was injected into different depths of an alluvial calcareous soil profile on the North China Plain. Subsequent movement of NO{sub 3} {sup -}N and its recovery by deep-rooted maize (Zea mays L.) and shallow-rooted eggplant (Solanum melongena L.) were studied. Under conventional water and nutrient management the mean recoveries of {sup 15}N-labeled nitrate from K{sup 15}NO{sub 3} injected at depths 15, 45, and 75 cm were 22.4, 13.8, and 7.8% by maize and 7.9, 4.9, and 2.7% by eggplant. The recovery rate by maize at each soil depth was significantly higher than by eggplant. The deeper the injection of nitrate the smaller the distance of its downward movement and this corresponded with the movement of soil water during crop growth. Deeper rooting crops with high root length density and high water consumption may therefore be grown to utilize high concentrations of residual nitrate in the subsoil from previous intensive cropping and to protect the environment. - Deep-rooted crops have a greater capacity than shallow-rooted crops to intercept residual nitrate from the subsoil and restrict its movement down to the shallow groundw0010at.

  7. Interception of residual nitrate from a calcareous alluvial soil profile on the North China Plain by deep-rooted crops: A 15N tracer study

    International Nuclear Information System (INIS)

    Ju, X.T.; Gao, Q.; Christie, P.; Zhang, F.S.

    2007-01-01

    15 N-labeled nitrate was injected into different depths of an alluvial calcareous soil profile on the North China Plain. Subsequent movement of NO 3 - N and its recovery by deep-rooted maize (Zea mays L.) and shallow-rooted eggplant (Solanum melongena L.) were studied. Under conventional water and nutrient management the mean recoveries of 15 N-labeled nitrate from K 15 NO 3 injected at depths 15, 45, and 75 cm were 22.4, 13.8, and 7.8% by maize and 7.9, 4.9, and 2.7% by eggplant. The recovery rate by maize at each soil depth was significantly higher than by eggplant. The deeper the injection of nitrate the smaller the distance of its downward movement and this corresponded with the movement of soil water during crop growth. Deeper rooting crops with high root length density and high water consumption may therefore be grown to utilize high concentrations of residual nitrate in the subsoil from previous intensive cropping and to protect the environment. - Deep-rooted crops have a greater capacity than shallow-rooted crops to intercept residual nitrate from the subsoil and restrict its movement down to the shallow groundwater

  8. Pesticide residue concentration in soil following conventional and Low-Input Crop Management in a Mediterranean agro-ecosystem, in Central Greece

    Energy Technology Data Exchange (ETDEWEB)

    Karasali, Helen, E-mail: e.karassali@bpi.gr [Laboratory of Chemical Control of Pesticides, Department of Pesticides Control and Phytopharmacy, Benaki Phytopathological Institute, 8 St. Delta Street, Kifissia, 14561 Athens (Greece); Marousopoulou, Anna [Laboratory of Chemical Control of Pesticides, Department of Pesticides Control and Phytopharmacy, Benaki Phytopathological Institute, 8 St. Delta Street, Kifissia, 14561 Athens (Greece); Machera, Kyriaki, E-mail: k.machera@bpi.gr [Laboratory of Pesticides Toxicology, Department of Pesticides Control and Phytopharmacy, Benaki Phytopathological Institute, 8 St. Delta Street, Kifissia, 14561 Athens (Greece)

    2016-01-15

    The present study was focused on the comparative evaluation of pesticide residues, determined in soil samples from Kopaida region, Greece before and after the implementation of Low-Input Crop Management (LCM) protocols. LCM has been suggested as an environmental friendly plant protection approach to be applied on crops growing in vulnerable to pollution ecosystems, with special focus on the site specific problems. In the case of the specific pilot area, the vulnerability was mainly related to the pollution of water bodies from agrochemicals attributed to diffuse pollution primarily from herbicides and secondarily from insecticides. A total of sixty-six soil samples, were collected and analyzed during a three-year monitoring study and the results of the determined pesticide residues were considered for the impact evaluation of applied plant protection methodology. The LCM was developed and applied in the main crops growing in the pilot area i.e. cotton, maize and industrial tomato. Herbicides active ingredients such as ethalfluralin, trifluralin, pendimethalin, S-metolachlor and fluometuron were detected in most samples at various concentrations. Ethalfluralin, which was the active ingredient present in the majority of the samples ranged from 0.01 μg g{sup −1} to 0.26 μg g{sup −1} soil dry weight. However, the amount of herbicides measured after the implementation of LCM for two cropping periods, was reduced by more than 75% in all cases. The method of analysis was based on the simultaneous extraction of the target compounds by mechanical shaking, followed by liquid chromatography mass spectrometric and gas chromatography electron capture (LC–MS/MS and GC–ECD) analysis. - Highlights: • Effect of Low Input Crop Management (LCM) in a vulnerable to pollution ecosystem. • LCM resulted in herbicide residues reduction in the range of 75 and 100% in all cases. • Conventional practices resulted in increased herbicide residues up to 18%. • Anthropogenic

  9. Impact of climate variability on N and C flux within the life cycle of biofuels produced from crop residues

    Science.gov (United States)

    Pourhashem, G.; Block, P. J.; Adler, P. R.; Spatari, S.

    2013-12-01

    Biofuels from agricultural feedstocks (lignocellulose) are under development to meet national policy objectives for producing domestic renewable fuels. Using crop residues such as corn stover as feedstock for biofuel production can minimize the risks associated with food market disruption; however, it demands managing residue removal to minimize soil carbon loss, erosion, and to ensure nutrient replacement. Emissions of nitrous oxide and changes to soil organic carbon (SOC) are subject to variability in time due to local climate conditions and cultivation practices. Our objective is to investigate the effect of climate inputs (precipitation and temperature) on biogeochemical greenhouse gas (GHG) emissions (N2O and SOC expressed as CO2) within the life cycle of biofuels produced from agricultural residues. Specifically, we investigate the impact of local climate variability on soil carbon and nitrogen fluxes over a 20-year biorefinery lifetime where biomass residue is used for lignocellulosic ethanol production. We investigate two cases studied previously (Pourhashem et al, 2013) where the fermentable sugars in the agricultural residue are converted to ethanol (biofuel) and the lignin byproduct is used in one of two ways: 1) power co-generation; or 2) application to land as a carbon/nutrient-rich amendment to soil. In the second case SOC losses are mitigated through returning the lignin component to land while the need for fertilizer addition is also eliminated, however in both cases N2O and SOC are subject to variability due to variable climate conditions. We used the biogeochemical model DayCent to predict soil carbon and nitrogen fluxes considering soil characteristics, tillage practices and local climate (e.g. temperature and rainfall). We address the impact of climate variability on the soil carbon and nitrogen fluxes by implementing a statistical bootstrap resampling method based on a historic data set (1980 to 2000). The ensuing probabilistic outputs from the

  10. Effects of water management practices on residue decomposition and degradation of Cry1Ac protein from crop-wild Bt rice hybrids and parental lines during winter fallow season.

    Science.gov (United States)

    Xiao, Manqiu; Dong, Shanshan; Li, Zhaolei; Tang, Xu; Chen, Yi; Yang, Shengmao; Wu, Chunyan; Ouyang, Dongxin; Fang, Changming; Song, Zhiping

    2015-12-01

    Rice is the staple diet of over half of the world's population and Bacillus thuringiensis (Bt) rice expressing insecticidal Cry proteins is ready for deployment. An assessment of the potential impact of Bt rice on the soil ecosystem under varied field management practices is urgently required. We used litter bags to assess the residue (leaves, stems and roots) decomposition dynamics of two transgenic rice lines (Kefeng6 and Kefeng8) containing stacked genes from Bt and sck (a modified CpTI gene encoding a cowpea trypsin inhibitor) (Bt/CpTI), a non-transgenic rice near-isoline (Minghui86), wild rice (Oryza rufipogon) and crop-wild Bt rice hybrid under contrasting conditions (drainage or continuous flooding) in the field. No significant difference was detected in the remaining mass, total C and total N among cultivars under aerobic conditions, whereas significant differences in the remaining mass and total C were detected between Kefeng6 and Kefeng8 and Minghui86 under the flooded condition. A higher decomposition rate constant (km) was measured under the flooded condition compared with the aerobic condition for leaf residues, whereas the reverse was observed for root residues. The enzyme-linked immunosorbent assay (ELISA), which was used to monitor the changes in the Cry1Ac protein in Bt rice residues, indicated that (1) the degradation of the Cry1Ac protein under both conditions best fit first-order kinetics, and the predicted DT50 (50% degradation time) of the Cry1Ac protein ranged from 3.6 to 32.5 days; (2) the Cry1Ac protein in the residue degraded relatively faster under aerobic conditions; and (3) by the end of the study (~154 days), the protein was present at a low concentration in the remaining residues under both conditions. The degradation rate constant was negatively correlated with the initial carbon content and positively correlated with the initial Cry1Ac protein concentration, but it was only correlated with the mass decomposition rate constants under

  11. A multi-sensor burned area algorithm for crop residue burning in northwestern India: validation and sources of error

    Science.gov (United States)

    Liu, T.; Marlier, M. E.; Karambelas, A. N.; Jain, M.; DeFries, R. S.

    2017-12-01

    A leading source of outdoor emissions in northwestern India comes from crop residue burning after the annual monsoon (kharif) and winter (rabi) crop harvests. Agricultural burned area, from which agricultural fire emissions are often derived, can be poorly quantified due to the mismatch between moderate-resolution satellite sensors and the relatively small size and short burn period of the fires. Many previous studies use the Global Fire Emissions Database (GFED), which is based on the Moderate Resolution Imaging Spectroradiometer (MODIS) burned area product MCD64A1, as an outdoor fires emissions dataset. Correction factors with MODIS active fire detections have previously attempted to account for small fires. We present a new burned area classification algorithm that leverages more frequent MODIS observations (500 m x 500 m) with higher spatial resolution Landsat (30 m x 30 m) observations. Our approach is based on two-tailed Normalized Burn Ratio (NBR) thresholds, abbreviated as ModL2T NBR, and results in an estimated 104 ± 55% higher burned area than GFEDv4.1s (version 4, MCD64A1 + small fires correction) in northwestern India during the 2003-2014 winter (October to November) burning seasons. Regional transport of winter fire emissions affect approximately 63 million people downwind. The general increase in burned area (+37% from 2003-2007 to 2008-2014) over the study period also correlates with increased mechanization (+58% in combine harvester usage from 2001-2002 to 2011-2012). Further, we find strong correlation between ModL2T NBR-derived burned area and results of an independent survey (r = 0.68) and previous studies (r = 0.92). Sources of error arise from small median landholding sizes (1-3 ha), heterogeneous spatial distribution of two dominant burning practices (partial and whole field), coarse spatio-temporal satellite resolution, cloud and haze cover, and limited Landsat scene availability. The burned area estimates of this study can be used to build

  12. Production of 15N-Labelled Liquid Organic Fertilisers Based on Manure and Crop Residue for Use in Fertigation Studies.

    Directory of Open Access Journals (Sweden)

    Belén Martínez-Alcántara

    Full Text Available Large quantities of crop residue and animal manure from agricultural and livestock activities are annually produced worldwide. With proper management, these residues are potentially valuable sources of plant nutrients, mainly N. Recycling such subproducts in sustainably-based agricultural systems can minimise the use of mineral fertilisers, and hence reduce the potential risk of surface and groundwater pollution. Therefore, the purpose of this study was to obtain (small scale two liquid labelled-organic fertilisers, an animal- and a vegetal-based organic (AO and VO, respectively fertiliser, to be used as organic N sources in subsequent fertigation studies. Forage maize (Zea mays L. grown under 15N-labelled fertiliser supply was used as raw material for VO fertiliser production, and also as 15N-labelled sheep feed to obtain 15N-labelled manure. The labelled faeces fraction was used as raw material for the AO fertiliser. The VO fertiliser was obtained after an acidic and an enzyme-driven hydrolysis. The AO fertiliser was obtained after acidic hydrolysis. The VO liquid fertiliser presented an N concentration of 330 mg·L-1, 85% of total N was organic, while ammonium and nitrate N accounted for 55% and 45% of the mineral nitrogen fraction, respectively. This fertiliser also exhibited high K, Ca and S concentrations and notable values for the remaining macro- and micronutrients. The AO liquid fertiliser had a similar total N concentration (496 mg·L-1, 82% of total N in an organic form to that of VO, but its mineral N fraction significantly differed, which came in a predominantly (95% ammonia form. It also had a high content of N, P, K and other macronutrients, and sufficient Fe, Zn, Mn, Cu and B levels, which suggests its suitability as a potential fertiliser. The percentage of 15N enrichment in both VO and AO liquid fertilisers exceeded 2% 15N atom excess, which enabled their use in subsequent assays run to assess nitrogen uptake efficiency.

  13. Slow pyrolyzed biochars from crop residues for soil metal(loid) immobilization and microbial community abundance in contaminated agricultural soils.

    Science.gov (United States)

    Igalavithana, Avanthi Deshani; Park, Jinje; Ryu, Changkook; Lee, Young Han; Hashimoto, Yohey; Huang, Longbin; Kwon, Eilhann E; Ok, Yong Sik; Lee, Sang Soo

    2017-06-01

    This study evaluated the feasibility of using biochars produced from three types of crop residues for immobilizing Pb and As and their effects on the abundance of microbial community in contaminated lowland paddy (P-soil) and upland (U-soil) agricultural soils. Biochars were produced from umbrella tree [Maesopsis eminii] wood bark [WB], cocopeat [CP], and palm kernel shell [PKS] at 500 °C by slow pyrolysis at a heating rate of 10 °C min -1 . Soils were incubated with 5% (w w -1 ) biochars at 25 °C and 70% water holding capacity for 45 d. The biochar effects on metal immobilization were evaluated by sequential extraction of the treated soil, and the microbial community was determined by microbial fatty acid profiles and dehydrogenase activity. The addition of WB caused the largest decrease in Pb in the exchangeable fraction (P-soil: 77.7%, U-soil: 91.5%), followed by CP (P-soil: 67.1%, U-soil: 81.1%) and PKS (P-soil: 9.1%, U-soil: 20.0%) compared to that by the control. In contrast, the additions of WB and CP increased the exchangeable As in U-soil by 84.6% and 14.8%, respectively. Alkalinity and high phosphorous content of biochars might be attributed to the Pb immobilization and As mobilization, respectively. The silicon content in biochars is also an influencing factor in increasing the As mobility. However, no considerable effects of biochars on the microbial community abundance and dehydrogenase activity were found in both soils. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Effects of Plant Residues in Two Types of Soil Texture on Soil characteristics and corn (Zea mays L. NS640 Yield in a Reduced -Tillage cropping System

    Directory of Open Access Journals (Sweden)

    E Hesami

    2018-05-01

    Full Text Available Introduction The impact of agronomy on the subsequent product in rotational cropping systems depends on factors such as plant type, duration of crop growth, soil moisture content, tillage type, irrigation method, the amount of nitrogen fertilizer, quantity and quality of returned crop residues to the soil. Prior cultivated crops improve the next crop yield by causing different conditions (nitrogen availability, organic matter and volume of available water in soil. This study was conducted due to importance of corn cultivation in Khuzestan and necessity of increasing the soil organic matter, moisture conservation and in the other hand the lack of sufficient information about the relationship between soil texture, type of preparatory crop in low-tillage condition and some soil characteristics and corn growth habits. The purpose of this experiment was to evaluate the effect of residue of preparatory crops in low plowing condition in two soil types on corn yield and some soil characteristics. Materials and Methods This experiment was carried out at Shooshtar city located in Khuzestan province. An experiment was performed by combined analysis in randomized complete block design in two fields and in two consecutive years with four replications. Two kinds of soil texture including: clay loam and clay sand. Five preparatory crops including: broad bean, wheat, canola, cabbage and fallow as control assigned as sub plots. SAS Ver. 9.1 statistical software was used for analysis of variance and comparison of means. Graphs were drawn using MS Excel software. All means were compared by Duncan test at 5% probability level. Results and Discussion The soil texture and the type of preparatory crop influenced the characteristics of the soil and corn grain yield. Returning the broad bean residue into two types of soil caused the highest grain yield of corn 10128.6 and 9547.9 kgha-1, respectively. The control treatment in sandy loam texture had the lowest corn seed

  15. Beneficiary role of grapes residue, an organic waste of agro-based industry causing environmental pollution - a new concept of crop production in hydroponics

    International Nuclear Information System (INIS)

    Butt, S.J.; Varis, S.

    2005-01-01

    The world is facing a serious threat of environmental pollution as a result of which our soils, air and water are becoming highly contaminated with the passage of time. Many epidemics have engulfed a number of countries in various diseases causing the loss of hundreds of thousands of human lives. The wastes of agro-based industries are mostly organic in nature, and if not properly handled, usually become nuisance and also the source of food for pathogens and other harmful microorganisms thus the surrounding becomes polluted. It has been reported that grapes residue (also called grapes marc or pressed grapes) was a serious environmental problem Tekirdag city of Turkey. This waste material was thrown out of the factory (Tekil Fabrikasi) after the extraction of grape juices used for different products. With dual objective, a plan was made to remove the waste material from polluted area subsequently managed to use it a source of soilless growing medium for the production horticultural crops through hydroponics system in the unheated greenhouse. The use of grapes residue for crop production is rare and hardly documented in the literature thus the idea is innovative in its nature that may lead to open the vista of new avenues. A trial of bag culture was conducted to evaluate the possibilities of use of grapes marc as a pure growing substrate for the production of lettuce and tomato crops. Quite encouraging results of a number of parameters of both the crops appeared against the soil-mixture (control). The studied characteristics were relating to vegetative, reproductive, yield physical and chemical performances and sensory traits. It is predicted that grapes marc possesses a great potential of organic rooting medium for growth and development of commercial crops, provided the climatic, nutritional and management activities scheduled in view of the kind and nature of crop cultivar to be grown under unheated glass house conditions. (author)

  16. Effects of agriculture crop residue burning on aerosol properties and long-range transport over northern India: A study using satellite data and model simulations

    Science.gov (United States)

    Vijayakumar, K.; Safai, P. D.; Devara, P. C. S.; Rao, S. Vijaya Bhaskara; Jayasankar, C. K.

    2016-09-01

    Agriculture crop residue burning in the tropics is a major source of the global atmospheric aerosols and monitoring their long-range transport is an important element in climate change studies. In this paper, we study the effects of agriculture crop residue burning on aerosol properties and long-range transport over northern India during a smoke event that occurred between 09 and 17 November 2013, with the help of satellite measurements and model simulation data. Satellite data observations on aerosol properties suggested transport of particles from agriculture crop residue burning in Indo-Gangetic Plains (IGP) over large regions. Additionally, ECMWF winds at 850 hPa have been used to trace the source, path and spatial extent of smoke events. Most of the smoke aerosols, during the study period, travel from a west-to-east pathway from the source-to-sink region. Furthermore, aerosol vertical profiles from CALIPSO show a layer of thick smoke extending from surface to an altitude of about 3 km. Smoke aerosols emitted from biomass burning activity from Punjab have been found to be a major contributor to the deterioration of local air quality over the NE Indian region due to their long range transport.

  17. Selective weed suppression by cover crop residues: effects of seed mass and timing of species’sensitivity

    NARCIS (Netherlands)

    Kruidhof, H.M.; Gallandt, E.R.; Haramoto, E.R.; Bastiaans, L.

    2011-01-01

    Laboratory bioassays have shown that large-seeded species better tolerate cover crop residue–mediated stress than small-seeded species. This provides the potential for selective suppression of small-seeded weeds in large-seeded crops. We conducted two field experiments in which seedling emergence of

  18. Sensitivity analysis of six soil organic matter models applied to the decomposition of animal manures and crop residues

    Directory of Open Access Journals (Sweden)

    Daniele Cavalli

    2016-09-01

    Full Text Available Two features distinguishing soil organic matter simulation models are the type of kinetics used to calculate pool decomposition rates, and the algorithm used to handle the effects of nitrogen (N shortage on carbon (C decomposition. Compared to widely used first-order kinetics, Monod kinetics more realistically represent organic matter decomposition, because they relate decomposition to both substrate and decomposer size. Most models impose a fixed C to N ratio for microbial biomass. When N required by microbial biomass to decompose a given amount of substrate-C is larger than soil available N, carbon decomposition rates are limited proportionally to N deficit (N inhibition hypothesis. Alternatively, C-overflow was proposed as a way of getting rid of excess C, by allocating it to a storage pool of polysaccharides. We built six models to compare the combinations of three decomposition kinetics (first-order, Monod, and reverse Monod, and two ways to simulate the effect of N shortage on C decomposition (N inhibition and C-overflow. We conducted sensitivity analysis to identify model parameters that mostly affected CO2 emissions and soil mineral N during a simulated 189-day laboratory incubation assuming constant water content and temperature. We evaluated model outputs sensitivity at different stages of organic matter decomposition in a soil amended with three inputs of increasing C to N ratio: liquid manure, solid manure, and low-N crop residue. Only few model parameters and their interactions were responsible for consistent variations of CO2 and soil mineral N. These parameters were mostly related to microbial biomass and to the partitioning of applied C among input pools, as well as their decomposition constants. In addition, in models with Monod kinetics, CO2 was also sensitive to a variation of the half-saturation constants. C-overflow enhanced pool decomposition compared to N inhibition hypothesis when N shortage occurred. Accumulated C in the

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

    International Nuclear Information System (INIS)

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

    1987-01-01

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

  20. Phytochemical Analysis and Antifungal Activity of Extracts from Leaves and Fruit Residues of Brazilian Savanna Plants Aiming Its Use as Safe Fungicides.

    Science.gov (United States)

    Breda, Caroline Alves; Gasperini, Alessandra Marcon; Garcia, Vera Lucia; Monteiro, Karin Maia; Bataglion, Giovana Anceski; Eberlin, Marcos Nogueira; Duarte, Marta Cristina Teixeira

    2016-08-01

    The increasing demand for safe food without preservatives or pesticides residues has encouraged several studies on natural products with antifungal activity and low toxicity. In this study, ethanolic extracts from leaves and fruit residues (peel and seeds) of three Brazilian savanna species (Acrocomia aculeata, Campomanesia adamantium and Caryocar brasiliense) were evaluated against phytopathogenic fungi. Additionally, the most active extract was chemically characterized by ESI-MS and its oral acute toxicity was evaluated. Extracts from C. brasiliense (pequi) peel and leaves were active against Alternaria alternata, Alternaria solani and Venturia pirina with minimal inhibitory concentrations between 350 and 1000 µg/mL. When incorporated in solid media, these extracts extended the lag phase of A. alternata and A. solani and reduced the growth rate of A. solani. Pequi peel extract showed better antifungal activity and their ESI-MS analysis revealed the presence of substances widely reported as antifungal such as gallic acid, quinic acid, ellagic acid, glucogalin and corilagin. The oral acute toxicity was relatively low, being considered safe for use as a potential natural fungicide.

  1. Field performance of a pneumatic row crop planter equipped with active toothed coulter for direct planting of corn in wheat residue

    Directory of Open Access Journals (Sweden)

    J. Nejadi

    2013-04-01

    Full Text Available In this research effects of active toothed coulter on planter penetration in semi-dried soils covered with previous wheat (triticum aestivum residue was studied. Therefore, effects of three levels of speed ratio (coulter peripheral speed/tractor forward speed; 1.22, 2, 3 at two previous residue levels (baled and non-baled and two modes of planter attachment (with and without row cleaner on the corn (zea mays planting depth and its uniformity, amount of surface residue, emergence rate index and seed spacings indices were investigated. Results showed that planting depth and its uniformity increased significantly with increasing speed ratio, so that desired planting depth was obtained at speed ratio of 2. The emergence rate index decreased with increase in speed ratio mainly due to increase in seeding depth at higher speed ratios. Miss and precision indices decreased in a significant manner with increase in the speed ratio. Other results showed that planting with row cleaner attachment into baled-out residue plots at speed ratio of 2 resulted in 31% decrease in miss and 30% decrease in precision indices as compared to control (inactive coulter. Quality of feed index at same conditions was 72%, the increase was up to 11% as compared to control. No significant difference was found between speed ratios of 2 and 3 for all the parameters studied. The results suggests that the row crop planter equipped with active toothed coulter and row cleaner attachment can be satisfactorily used for direct corn planting in hard soils covered with previous crop residues.

  2. Utilização do nitrogênio (15N residual de coberturas de solo e da uréia pela cultura do milho Utilization of residual nitrogen (15N from cover crop and urea by corn

    Directory of Open Access Journals (Sweden)

    Edson Cabral da Silva

    2006-12-01

    Full Text Available Geralmente, grande parte do N de fertilizantes minerais e de plantas de cobertura de solo não é aproveitada pelo milho no cultivo imediato à aplicação, o qual pode ser absorvido pelas culturas cultivadas subseqüentemente. O objetivo deste trabalho foi avaliar o aproveitamento pelo milho do N residual da uréia, da crotalária (Crotalaria juncea e do milheto (Pennisetum americanum marcados com 15N, aplicados ao milho cultivado em sistema plantio direto, no ano agrícola anterior, num Latossolo Vermelho distroférrico no Cerrado. O estudo foi desenvolvido na fazenda experimental da Faculdade de Engenharia de Ilha Solteira-UNESP, Selvíria (MS, em áreas distintas. O delineamento experimental foi de blocos ao acaso com 15 tratamentos e quatro repetições, aplicados ao milho em 2001/02 e 2002/03. Os tratamentos foram dispostos em esquema fatorial 3 x 5, compreendendo a combinação de três coberturas de solo: crotalária juncea, milheto e vegetação espontânea (pousio, e cinco doses de N-uréia: 0, 30, 80, 130 e 180 kg ha-1. Após a colheita do milho, as duas áreas permaneceram em pousio nas entressafras e, em seguida, cultivadas novamente com milho, safras 2002/03 (experimento 1 e 2003/04 (experimento 2, utilizando adubação similar em todas as parcelas, para distinguir o efeito do N residual. O aproveitamento médio do N residual da parte aérea do milheto e da crotalária pelo milho foi inferior a 3,5 e 3 %, respectivamente, da quantidade inicial. A quantidade de N residual da uréia absorvida pelo milho aumentou de forma quadrática, no experimento 1, e linear, no experimento 2, em relação à dose de N aplicada, sendo o aproveitamento desta inferior a 3 %. As coberturas de solo não influenciaram o aproveitamento pelo milho do N residual da uréia, e vice-versa.The majority of N from mineral fertilizers and cover crops is usually not used by the very next corn crop, but can be absorbed by follow-up crops. The objective of this

  3. Effect of straw mulch residues of previous crop oats on the weed population in direct seeded faba bean in Organic Farming

    Directory of Open Access Journals (Sweden)

    Massucati, Luiz Felipe Perrone

    2014-02-01

    Full Text Available Under conditions of Organic Farming, we investigated whether direct seeding of faba bean (Vicia faba L. into straw mulch from residues of precrop oats used for weed control enables at least occasional/opportunistic direct seeding in Organic Agriculture. Eight field trials were carried out at different study sites in North Rhine-Westphalia, Germany, in 2008-2009 and 2009-2010. Direct seeding (DS was performed into mulch layers of 0,4 and 6 t ha-1 of straw residues applied to the remaining stubble, simulating different yield levels of the precrop oats. LBS was used as a reference treatment, where straw was harvested, stubble tillage performed and seedbed prepared in fall and oil radish (Raphanus sativus grown as winter cover crop. Mouldboard ploughing combined with conventional seedbed preparation was performed in early spring to V. faba. Compared with LBS, straw mulch with subsequent direct seeding suppressed especially dicotyledonous annuals significantly. DS treatments with straw reduced the abundance of this group by 81 and 85% compared with LBS. Straw mulch resulted in effective suppression of photosensitive weeds such as Matricaria spp. and late germinating Chenopodium album. Grasses and perennial species occurred independent of the amount of straw. Compared with DS, the abundance of these weeds was reduced by 64 and 82% in LBS treatment. The shoot dry matter production of faba bean was retarded by DS compared with LBS, but significant yield losses could be avoided with straw residues of at least 4 t ha-1. Sufficient amount of straw of from the previous crop is a key criterion to facilitate organic no-till farming of faba bean in a suitable crop sequence when pressure of perennials and grasses is low.

  4. Simultaneous determination of residues of metalaxyl, cyazofamid and a cyazofamid metabolite in tobacco leaves and soil by liquid chromatography with tandem mass spectrometry.

    Science.gov (United States)

    Wu, Sizhuo; Yu, Weiwei; Sun, Caiyuan; Zheng, Kunming; Zhang, Haizhen; Huang, Min; Hu, Deyu; Zhang, Kankan

    2018-04-01

    A simple method was developed and validated for the simultaneous determination of metalaxyl, cyazofamid and the cyazofamid metabolite 4-chloro-5-p-tolylimidazole-2-carbonitrile (CCIM) by liquid chromatography with tandem mass spectrometry. The three target compounds were extracted from tobacco and soil with acetonitrile containing 0.1% acetic acid, and the extracts were purified using octadecylsilane. The proposed method showed satisfactory linearity (R 2 ≥ 0.9985) for the target compounds. The limits of detection for metalaxyl, cyazofamid and CCIM were 0.006, 0.06 and 0.06 mg/kg in soil and green tobacco leaves and 0.03, 0.3 and 0.3 mg/kg in cured tobacco leaves, respectively. The limits of quantification for metalaxyl, cyazofamid and CCIM were 0.02, 0.2 and 0.2 mg/kg in soil and green tobacco leaves and 0.1, 1 and 1 mg/kg in cured tobacco leaves, respectively. The average recoveries from soil and tobacco were 72.91-98.40% for metalaxyl, 76.73-105.80% for cyazofamid and 74.48-106.45% for CCIM. The relative standard deviation range was 1.23-6.99%. The developed method was successfully applied to analysis of residues of metalaxyl, cyazofamid and CCIM in real soil and tobacco samples. The results indicated that the established method could meet the requirement for the analysis of trace amounts of all three analytes in soil and tobacco. Copyright © 2017 John Wiley & Sons, Ltd.

  5. An assay of the utilization of the residual use of a N fertilizer [(15NH4)2SO4] made by a wheat crop, using an isotope technique

    International Nuclear Information System (INIS)

    Bujan, A.; Quitegui, M.I.; Quitegui, M.C.; Ghelfi, L.E.P. de; Deybe, D.

    1982-01-01

    An experimental study was carried out in order to determine the residual use of a N fertilizer made by wheat during a year. Wheat was seeded in plots which had been cropped the year before with inoculated soybean (glycine max), non-inoculated soybean and sorghum (sorghum caffrorum) fertilized with (NH 4 ) 2 SO 4 at two different levels: 20 and 100kg N/ha tagged with 5% excess 15 N and 1% respectively. It was concluded that:1) the % excess 15 N used in the previous crops were sufficient to determine residuality from the N fertilizer. 2)when the previous crop was non-inoculated soybean, the total nitrogen content of the wheat grains was significantly higher than when the previous crop was either inoculated soybean or sorghum. The total N content was significantly higher on the plots fertilized with 100KgN/ha than on those with 20kgN/ha.3) non-inoculated - and inoculated soybeans determined higher wheat grain yields than sorghum as previous crops. Higher wheat grain yields ocurred on the 100kgN/ha fertilized plots. Higher residual N content ocurred on the 100KgN/ha fertilized plots. Non-inoculated soybean determined higher residual N content in grain than inoculated soybean and sorghum; inoculated soybean determined higher content than sorghum. There were no significant differences in residual N content in the plants depending on the previous crop. (Author) [pt

  6. Can we throw information out of visual working memory and does this leave informational residue in long-term memory?

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    Ashleigh Monette Maxcey

    2014-04-01

    Full Text Available Can we entirely erase a temporary memory representation from mind? This question has been addressed in several recent studies that tested the specific hypothesis that a representation can be erased from visual working memory based on a cue that indicated that the representation was no longer necessary for the task. In addition to behavioral results that are consistent with the idea that we can throw information out of visual working memory, recent neurophysiological recordings support this proposal. However, given the infinite capacity of long-term memory, it is unclear whether throwing a representation out of visual working memory really removes its effects on memory entirely. In this paper we advocate for an approach that examines our ability to erase memory representations from working memory, as well as possible traces that those erased representations leave in long-term memory.

  7. Expression of allelopathy in the soil environment: Soil concentration and activity of benzoxazinoid compounds released by rye cover crop residue

    Science.gov (United States)

    The activity of allelopathic compounds is often reduced in the soil environment where processes involving release from donor plant material, soil adsorption and degradation, and uptake by receptor plants naturally result in complex interactions. Rye (Secale cereale L.) cover crops are known to supp...

  8. Integrating Characterization of Smallholders’ Feeding Practices with On-Farm Feeding Trials to Improve Utilization of Crop Residues on Smallholder Farms

    Directory of Open Access Journals (Sweden)

    B. O. Kashongwe

    2017-01-01

    Full Text Available This study characterized wheat straw feeding practices in smallholder farms using cross sectional survey and the results informed the design of an experiment to improve the nutritive value of wheat straw with urea and yeast culture treatment. Three diets tested in 49 days’ feeding trial were farmers’ rainy season feeding practice (FP, addition of urea to wheat straw at the time of feeding (USWS, and 14 days’ incubation of straw with urea (UTWS. Yeast culture (15 g/day was mixed with commercial dairy meal at the point of feeding. Survey data identified farmers’ strategies in utilizing crop residues of which most important were improving storage facility (77.6%, adding molasses (54.5%, and buying a shredding machine (45.1%. On-farm feeding trial showed that intake was higher for UTWS than (p<0.05 for USWS while milk yield was higher with FP than (p<0.005 with UTWS or USWS but not different (p≥0.05 between UTWS and USWS. Results imply that farmers feeding practices of crop residues may be improved for dairy cows’ feeding and therefore UTWS could be used to support maintenance and milk production during dry season. Improving farmers feed storage facilities and training on incubation of wheat straw for dairy cattle feeding were recommended.

  9. Recovery of resources for advanced life support space applications: effect of retention time on biodegradation of two crop residues in a fed-batch, continuous stirred tank reactor

    Science.gov (United States)

    Strayer, R. F.; Finger, B. W.; Alazraki, M. P.; Cook, K.; Garland, J. L.

    2002-01-01

    Bioreactor retention time is a key process variable that will influence costs that are relevant to long distance space travel or long duration space habitation. However. little is known about the effects of this parameter on the microbiological treatment options that are being proposed for Advanced Life Support (ALS) systems. Two bioreactor studies were designed to examine this variable. In the first one, six retention times ranging from 1.3 to 21.3 days--were run in duplicate, 81 working-volume continuous stirred tank reactors (CSTR) that were fed ALS wheat residues. Ash-free dry weight loss, carbon mineralization, soluble TOC reduction, changes in fiber content (cellulose, hemicellulose, and lignin), bacterial numbers, and mineral recoveries were monitored. At short retention times--1.33 days--biodegradation was poor (total: 16-20%, cellulose - 12%, hemicellulose - 28%) but soluble TOC was decreased by 75-80% and recovery of major crop inorganic nutrients was adequate, except for phosphorus. A high proportion of the total bacteria (ca. 83%) was actively respiring. At the longest retention time tested, 21.3 days, biodegradation was good (total: 55-60%, cellulose ca. 70%, hemicellulose - ca. 55%) and soluble TOC was decreased by 80%. Recovery of major nutrients, except phosphorus, remained adequate. A very low proportion of total bacteria was actively respiring (ca. 16%). The second bioreactor study used potato residue to determine if even shorter retention times could be used (range 0.25-2.0 days). Although overall biodegradation deteriorated, the degradation of soluble TOC continued to be ca. 75%. We conclude that if the goal of ALS bioprocessing is maximal degradation of crop residues, including cellulose, then retention times of 10 days or longer will be needed. If the goal is to provide inorganic nutrients with the smallest volume/weight bioreactor possible, then a retention time of 1 day (or less) is sufficient.

  10. Residues, spatial distribution and risk assessment of DDTs and HCHs in agricultural soil and crops from the Tibetan Plateau.

    Science.gov (United States)

    Wang, Chuanfei; Wang, Xiaoping; Gong, Ping; Yao, Tandong

    2016-04-01

    Due to its high elevation and cold temperature, the Tibetan Plateau (TP) is regarded as the "Third Pole". Different from other polar regions, which are truly remote, the TP has a small population and a few agricultural activities. In this study, agricultural soil and crop samples (including highland barley and rape) were collected in the main farmland of the TP to obtain the contamination levels of dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH) in the Tibetan agricultural system as well as the relevant human exposure risks. The average concentrations of DDTs and HCHs in the agricultural soil, highland barley and rape were 1.36, 0.661, 1.03 ng/g dw and 0.349, 0.0364, 0.0225 ng/g dw, respectively. In the agricultural soil, DDTs and HCHs metabolism (DDE, DDD and β-HCH) were abundant, which indicated a "historical" source, whereas crops contained a similar composition ((DDE + DDD)/DDT, α/β-HCH and α/γ-HCH) to that of wild plants, suggesting that the DDTs and HCHs in crops are likely from long range atmospheric transport. The human health risks via non-dietary and dietary to DDTs and HCHs in the farmland were assessed. All of the hazard index (HI) values of DDTs and HCHs for non-carcinogenic risks were Tibetan residents. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. How Does Alkali Aid Protein Extraction in Green Tea Leaf Residue: A Basis for Integrated Biorefinery of Leaves

    Science.gov (United States)

    Zhang, Chen; Sanders, Johan P. M.; Xiao, Ting T.; Bruins, Marieke E.

    2015-01-01

    Leaf protein can be obtained cost-efficiently by alkaline extraction, but overuse of chemicals and low quality of (denatured) protein limits its application. The research objective was to investigate how alkali aids protein extraction of green tea leaf residue, and use these results for further improvements in alkaline protein biorefinery. Protein extraction yield was studied for correlation to morphology of leaf tissue structure, protein solubility and hydrolysis degree, and yields of non-protein components obtained at various conditions. Alkaline protein extraction was not facilitated by increased solubility or hydrolysis of protein, but positively correlated to leaf tissue disruption. HG pectin, RGII pectin, and organic acids were extracted before protein extraction, which was followed by the extraction of cellulose and hemi-cellulose. RGI pectin and lignin were both linear to protein yield. The yields of these two components were 80% and 25% respectively when 95% protein was extracted, which indicated that RGI pectin is more likely to be the key limitation to leaf protein extraction. An integrated biorefinery was designed based on these results. PMID:26200774

  12. How Does Alkali Aid Protein Extraction in Green Tea Leaf Residue: A Basis for Integrated Biorefinery of Leaves.

    Directory of Open Access Journals (Sweden)

    Chen Zhang

    Full Text Available Leaf protein can be obtained cost-efficiently by alkaline extraction, but overuse of chemicals and low quality of (denatured protein limits its application. The research objective was to investigate how alkali aids protein extraction of green tea leaf residue, and use these results for further improvements in alkaline protein biorefinery. Protein extraction yield was studied for correlation to morphology of leaf tissue structure, protein solubility and hydrolysis degree, and yields of non-protein components obtained at various conditions. Alkaline protein extraction was not facilitated by increased solubility or hydrolysis of protein, but positively correlated to leaf tissue disruption. HG pectin, RGII pectin, and organic acids were extracted before protein extraction, which was followed by the extraction of cellulose and hemi-cellulose. RGI pectin and lignin were both linear to protein yield. The yields of these two components were 80% and 25% respectively when 95% protein was extracted, which indicated that RGI pectin is more likely to be the key limitation to leaf protein extraction. An integrated biorefinery was designed based on these results.

  13. Minor crops for export: a case study of boscalid, pyraclostrobin, lufenuron and lambda-cyhalothrin residue levels on green beans and spring onions in Egypt.

    Science.gov (United States)

    Hanafi, Ahmad; Garau, Vincenzo L; Caboni, Pierluigi; Sarais, Giorgia; Cabras, Paolo

    2010-08-01

    Dissipation rates of boscalid [2-chloro-N-(4' -chlorobiphenyl-2-yl)nicotinamide], pyraclostrobin [methyl 2-[1-(4-chlorophenyl) pyrazol-3-yloxymethyl]-N-methoxycarbanilate], lufenuron [(RS)-1-[2,5-dichloro-4-(1,1,2,3,3,3-hexafluoropropoxy)phenyl]-3-(2,6-difluorobenzoyl)urea] and lambda-cyhalothrin [(R)-cyano(3-phenoxyphenyl)methyl (1S,3S)-rel-3-[(1Z)-2-chloro-3,3,3-trifluoro-1-propenyl]-2,2-dimethylcyclopropanecarboxylate] in green beans and spring onions under Egyptian field conditions were studied. Field trials were carried out in 2008 in a Blue Nile farm, located at 70 kilometer (km) from Cairo (Egypt). The pesticides were sprayed at the recommended rate and samples were collected at pre-determined intervals. After treatment (T(0)) the pesticide residues in green beans were 7 times lower than in spring onions. This is due to a different structure of vegetable plant in the two crops. In spring onions, half-life (t(1/2)) of pyraclostrobin and lufenuron was 3.1 days and 9.8 days respectively. At day 14th (T(14)) after treatment boscalid residues were below the Maximum Residue Limit (MRL) (0.34 versus 0.5 mg/kg), pyraclostrobin and lambda -cyhalothrin residues were not detectable (ND), while lufenuron residues were above the MRL (0.06 versus 0.02 mg/kg). In green beans, at T(0), levels of boscalid, lufenuron and lambda -cyhalothrin were below the MRL (0.28 versus 2 mg/kg; ND versus 0.02 mg/kg; 0.06 versus 0.2 mg/kg, respectively) while, after 7 days treatment (T(7)) pyraclostrobin residues were above the MRL (0.03 versus 0.02 mg/kg). However, after 14 days the residue level could go below the MRL (0.02 mg/kg), as observed in spring onions.

  14. Exploration of a mechanism for the production of highly unsaturated fatty acids in Scenedesmus sp. at low temperature grown on oil crop residue based medium.

    Science.gov (United States)

    Lu, Qian; Li, Jun; Wang, Jinghan; Li, Kun; Li, Jingjing; Han, Pei; Chen, Paul; Zhou, Wenguang

    2017-11-01

    The ability of algae to produce lipids comprising of unsaturated fatty acids varies with strains and culture conditions. This study investigates the effect of temperature on the production of unsaturated fatty acids in Scenedesmus sp. grown on oil crop residue based medium. At low temperature (10°C), synthesis of lipids compromising of high contents of unsaturated fatty acids took place primarily in the early stage while protein accumulation mainly occurred in the late stage. This stepwise lipid-protein synthesis process was found to be associated with the contents of acetyl-CoA and α-KG in the algal cells. A mechanism was proposed and tested through simulation experiments which quantified the carbon flux allocation in algal cells at different cultivation stages. It is concluded that low culture temperature such as 10°C is suitable for the production of lipids comprising of unsaturated fatty acids. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Effects of tillage methods, corn residue mulch and n fertilizer levels on the wheat crop productivity under the rain fed condition of loess plateau china

    International Nuclear Information System (INIS)

    Tanveer, S.K.; Zhang, J.L.; Lu, X.L.; Wen, X.; Tanveer, S.K.

    2015-01-01

    A 2 years study was conducted to assess the effects of different tillage methods (Chisel plough tillage, Zero-tillage, Rotary tillage and Mould board plough tillage), two mulch levels (M0 i.e. No corn residue mulch and M1 i.e. Corn residue mulch) and 5 N fertilizer levels (0, 80, 160, 240 and 320 kg N/ha) on the wheat crop productivity under the rain fed condition of Loess Plateau, China. Factorial experiment with three replications, having strip, split-split arrangement, with tillage methods in the main plots, mulch levels in sub- plots and N-fertilizer levels in the sub-sub plots was used for this study. Due to variations in rainfalls, during the year, 2010-11, maximum grain yields i.e. 6.58 t/ha and 6.72 t/ha were recorded in case of Zero tillage planting method and similarly in case of 80 kg N/ha, while during the cropping year 2011-12 equal grain yields were recorded in case of all tillage methods, however maximum grain yield (7.46 t /ha) was recorded in case of 320 kg N/ha, N fertilizer level. On two years average basis, maximum grain yields i.e. 6.75 t/ha and 6.80 t/ha were recorded in case of Zero tillage planting method and similarly in case of 80 kg N/ha as compared with the other tillage methods or N fertilizer levels. Use of mulch reduced > 40% weeds infestation. Economic analysis shows that Zero tillage and minimum use of N fertilizer according to the projected rainfalls along with the use of mulch are both economic and environmental friendly. (author)

  16. The Effect of Organic and Inorganic Fertilizers on the Yield of Two Contrasting Soybean Varieties and Residual Nutrient Effects on a Subsequent Finger Millet Crop

    Directory of Open Access Journals (Sweden)

    Zerihun Abebe

    2017-06-01

    Full Text Available The problems of low soil fertility resulting from continuous monocropping, crop residue removal and limited fertilizer use represent key challenges to produce surplus food for the ever increasing population of Ethiopia. However, the practices of crop rotation and integrated sources of fertilizer uses could potentially improve soil fertility and productivity. In 2012 and 2014, soybean with different trials consisting of two soybean varieties (Boshe and Ethio-ugozilavia, three levels of farm yard manure (FYM (3, 6 and 9 t/ha and three phosphorus levels (8, 16 and 24 kg P ha−1 were combinedin2×3×3factorialarrangements. Twosoybeanvarietiesreceivingnofertilizerapplication followed by finger millet receiving a recommended rate (20 kg P/ha were included. The experiment was laid out in a randomized complete block design with three replications. In 2013 and 2015, finger millet was planted on each soybean plot as per previous treatment arrangements to evaluate the effect of the precursor crop (soybean and integrated fertilizer application on yield performance of the subsequent finger millet. Soil pH, organic carbon, total nitrogen and available phosphorus before planting and after crop harvest of soybean in each year showed treatment differences. Both precursor crop and fertilizer application had a positive effect on soil fertility status and, hence, improved the performance of the subsequent finger millet. On the other hand, since the rainfall amount and distribution were different in the 2012 and 2014 seasons, the response of soybean varieties to applied fertilizers was significantly affected, and the correlation between soybean yield and annual rainfall was strongly positive. Use of an early maturing soybean variety (Boshe with the lowest rates of organicandinorganicfertilizersgavesignificantlyhigheryieldin2012(shortrainyseasoncompared with other treatment combinations. In the 2014 cropping season, however, ‘Ethio-ugozilavia’ showed

  17. Automated multi-plug filtration cleanup for liquid chromatographic-tandem mass spectrometric pesticide multi-residue analysis in representative crop commodities.

    Science.gov (United States)

    Qin, Yuhong; Zhang, Jingru; Zhang, Yuan; Li, Fangbing; Han, Yongtao; Zou, Nan; Xu, Haowei; Qian, Meiyuan; Pan, Canping

    2016-09-02

    An automated multi-plug filtration cleanup (m-PFC) method on modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) extracts was developed. The automatic device was aimed to reduce labor-consuming manual operation workload in the cleanup steps. It could control the volume and the speed of pulling and pushing cycles accurately. In this work, m-PFC was based on multi-walled carbon nanotubes (MWCNTs) mixed with other sorbents and anhydrous magnesium sulfate (MgSO4) in a packed tip for analysis of pesticide multi-residues in crop commodities followed by liquid chromatography with tandem mass spectrometric (LC-MS/MS) detection. It was validated by analyzing 25 pesticides in six representative matrices spiked at two concentration levels of 10 and 100μg/kg. Salts, sorbents, m-PFC procedure, automated pulling and pushing volume, automated pulling speed, and pushing speed for each matrix were optimized. After optimization, two general automated m-PFC methods were introduced to relatively simple (apple, citrus fruit, peanut) and relatively complex (spinach, leek, green tea) matrices. Spike recoveries were within 83 and 108% and 1-14% RSD for most analytes in the tested matrices. Matrix-matched calibrations were performed with the coefficients of determination >0.997 between concentration levels of 10 and 1000μg/kg. The developed method was successfully applied to the determination of pesticide residues in market samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Miscanthus establishment and overwintering in the Midwest USA: a regional modeling study of crop residue management on critical minimum soil temperatures.

    Directory of Open Access Journals (Sweden)

    Christopher J Kucharik

    Full Text Available Miscanthus is an intriguing cellulosic bioenergy feedstock because its aboveground productivity is high for low amounts of agrochemical inputs, but soil temperatures below -3.5 °C could threaten successful cultivation in temperate regions. We used a combination of observed soil temperatures and the Agro-IBIS model to investigate how strategic residue management could reduce the risk of rhizome threatening soil temperatures. This objective was addressed using a historical (1978-2007 reconstruction of extreme minimum 10 cm soil temperatures experienced across the Midwest US and model sensitivity studies that quantified the impact of crop residue on soil temperatures. At observation sites and for simulations that had bare soil, two critical soil temperature thresholds (50% rhizome winterkill at -3.5 °C and -6.0 °C for different Miscanthus genotypes were reached at rhizome planting depth (10 cm over large geographic areas. The coldest average annual extreme 10 cm soil temperatures were between -8 °C to -11 °C across North Dakota, South Dakota, and Minnesota. Large portions of the region experienced 10 cm soil temperatures below -3.5 °C in 75% or greater for all years, and portions of North and South Dakota, Minnesota, and Wisconsin experienced soil temperatures below -6.0 °C in 50-60% of all years. For simulated management options that established varied thicknesses (1-5 cm of miscanthus straw following harvest, extreme minimum soil temperatures increased by 2.5 °C to 6 °C compared to bare soil, with the greatest warming associated with thicker residue layers. While the likelihood of 10 cm soil temperatures reaching -3.5 °C was greatly reduced with 2-5 cm of surface residue, portions of the Dakotas, Nebraska, Minnesota, and Wisconsin still experienced temperatures colder than -3.5 °C in 50-80% of all years. Nonetheless, strategic residue management could help increase the likelihood of overwintering of miscanthus rhizomes in the first few

  19. Utilization of crops residues as compost and biochar for improving soil physical properties and upland rice productivity

    Directory of Open Access Journals (Sweden)

    J. Barus

    2016-07-01

    Full Text Available The abundance of crops waste in the agricultural field can be converted to organic fertilizer throughout the process of composting or pyrolysis to return back into the soil. The study aimed to elucidate the effect of compost and biochar application on the physical properties and productivity of upland rice at Village of Sukaraja Nuban, Batanghari Nuban Sub district, East Lampung Regency in 2015. The amendment treatments were A. control; B. 10 t rice husk biochar/ ha; C. 10 t maize cob biochar/ha; D. 10 t straw compost/ha; E. 10 t stover compost/ha, F. 10 t rice husk biochar/ha + 10 t straw compost/ha; F. 10 t maize cob biochar/ha + 10 t maize stover compost/ha. The treatments were arranged in randomized block design with four replicates. The plot size for each treatment was 10 x 20 m. After incubation for about one month, undisturbed soil samples were taken using copper ring at 10–20 cm depth for laboratory analyzes. Analyses of soil physical properties included bulk density, particle density, total porosity, drainage porosity, and soil water condition. Plant observations conducted at harvest were plant height, number of panicle, number of grain/panicle, and grain weight/plot. Results of the study showed that biochar and compost improved soil physical properties such as bulk density, total porosity, fast drainage pores, water content, and permeability of soil. The combination of rice husk biochar and straw compost gave better effect than single applications on rice production components (numbers of panicle and grains of rice, and gave the highest yield of 4.875 t/ha.

  20. Prescribed fire experiences on crop residue removal for biomass exploitations. Application to the maritime pine forests in the Mediterranean Basin.

    Science.gov (United States)

    Molina, Juan Ramón; García, Juan Pedro; Fernández, Juan José; Rodríguez Y Silva, Francisco

    2018-01-15

    Socioeconomic changes, climate change, rural migration and fire exclusion have led to a high woody biomass accumulation increasing potential wildfire severity. Mechanical thinning and prescribed burning practices are commonly used to prevent large fires. The purpose of this study was to assess burning treatment effectiveness following mechanical thinning from biomass harvesting. Prescribed burning to reduce residue removal could help mitigate fire behavior, mainly in strategic management or critical focal points. Field samplings were conducted before and immediately after burnings on different environmental scenarios where fuel load was classified by categories. Prescribed fires reduced available fuel in all fuel categories, mainly in surface litter layer. Total fuel load reduction ranged from 59.07% to 86.18%. In this sense, fuel reduction effects were more pronounced when burns were conducted fewer than 10% on surface litter moisture. The difference in fuel consumption among scenarios was higher for most all woody fuel components and decomposition litter layer than for surface litter layer. Managers can use this information to design technical prescription to achieve the targets while decomposed litter retention maintaining the soil properties and biodiversity. Understanding the most effective "burn window" should help better plan prescribed burning, both in term of fire behavior and fuel consumption, without altering ecosystem properties. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Weeds Cause Losses in Field Crops through Allelopathy

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    Ali ZOHAIB

    2016-03-01

    Full Text Available A large number of weeds are known to be associated with crops and causing economic losses. Weeds interfere with crops through competition and allelopathy. They produce secondary metabolites known as allelochemicals, which belong to numerous chemical classes such as phenolics, alkaloids, fatty acids, indoles, terpens etc. However, phenolics are the predominant class of allelochemicals. The allelochemicals release from weed plants takes place through leaf leachates, decomposition of plant residues, volatilization and root exudates. Weeds leave huge quantities of their residues in field and affect the associated, as well as succeeding crops, in various cropping systems. Liberation of allelochemicals from weeds affects the germination, stand establishment, growth, yield and physiology of crop plants. They cause substantial reduction in germination and growth of the crop plants by altering various physiological processes such as enzyme activity, protein synthesis, photosynthesis, respiration, cell division and enlargement, which ultimately leads to a significant reduction in crop yield. In crux, allelopathic weeds represent a potential threat for crop plants and cause economic losses.

  2. An analysis of producing ethanol and electric power from woody residues and agricultural crops in East Texas

    Science.gov (United States)

    Ismayilova, Rubaba Mammad

    The increasing U.S. dependence on imported oil; the contribution of fossil fuels to the greenhouse gas emissions and the climate change issue; the current level of energy prices and other environmental concerns have increased world interest in renewable energy sources. Biomass is a large, diverse, readily exploitable resource. This dissertation examines the biomass potential in Eastern Texas by examining a 44 county region. This examination considers the potential establishment of a 100-megawatt (MW) power plant and a 20 million gallon per year (MMGY) ethanol plant using lignocellulosic biomass. The biomass sources considered are switchgrass, sugarcane bagasse, and logging residues. In the case of electricity generation, co-firing scenarios are also investigated. The research analyzes the key indicators involved with economic costs and benefits, environmental and social impacts. The bioenergy production possibilities considered here were biofeedstock supported electric power and cellulosic ethanol production. The results were integrated into a comprehensive set of information that addresses the effects of biomass energy development in the region. The analysis indicates that none of the counties in East Texas have sufficient biomass to individually sustain either a 100% biomass fired power plant or the cellulosic ethanol plant. Such plants would only be feasible at the regional level. Co-firing biomass with coal, however, does provide a most attractive alternative for the study region. The results indicate further that basing the decision solely on economics of feedstock availability and costs would suggest that bioenergy, as a renewable energy, is not a viable energy alternative. Accounting for some environmental and social benefits accruing to the region from bioenergy production together with the feedstock economics, however, suggests that government subsidies, up to the amount of accruing benefits, could make the bioenergies an attractive business opportunity

  3. Rhizosphere organic anions play a minor role in improving crop species’ ability to take up residual phosphorus (P in agricultural soils low in P availability

    Directory of Open Access Journals (Sweden)

    Yanliang Wang

    2016-11-01

    Full Text Available Many arable lands have accumulated large reserves of residual phosphorus (P and a relatively large proportion of soil P is less available for uptake by plants. Root released organic anions are widely documented as a key physiological strategy to enhance P availability, while limited information has been generated on the contribution of rhizosphere organic anions to P utilization by crops grown in agricultural soils that are low in available P and high in extractable Ca, Al and Fe. We studied the role of rhizosphere organic anions in P uptake from residual P in four common crops Triticum aestivum, Avena sativa, Solanum tuberosum and Brassica napus in low- and high-P availability agricultural soils from long-term fertilization field trials in a mini-rhizotron experiment with four replications. Malate was generally the dominant organic anion. More rhizosphere citrate was detected in low P soils than in high P soil. Brassica napus showed 74-103% increase of malate in low P loam, compared with clay loam. Avena sativa had the greatest rhizosphere citrate concentration in all soils (5.3-15.2 mol g-1 root DW. Avena sativa also showed the highest level of root colonization by arbuscular mycorrhizal fungi (36% and 40%, the greatest root mass ratio (0.51 and 0.66 in the low-P clay loam and loam respectively, and the greatest total P uptake (5.92 mg P/mini-rhizotron in the low-P loam. Brassica napus had 15-44% more rhizosphere APase activity, ~0.1-0.4 units lower rhizosphere pH than other species, the greatest increase in rhizosphere water-soluble P in the low-P soils, and the greatest total P uptake in the low-P clay loam. Shoot P content was mainly explained by rhizosphere APase activity, water-soluble P and pH within low P soils across species. Within species, P uptake was mainly linked to rhizosphere water soluble P, APase and pH in low P soils. The effects of rhizosphere organic anions varied among species and they appeared to play minor roles in

  4. Rhizosphere Organic Anions Play a Minor Role in Improving Crop Species' Ability to Take Up Residual Phosphorus (P) in Agricultural Soils Low in P Availability.

    Science.gov (United States)

    Wang, Yanliang; Krogstad, Tore; Clarke, Jihong L; Hallama, Moritz; Øgaard, Anne F; Eich-Greatorex, Susanne; Kandeler, Ellen; Clarke, Nicholas

    2016-01-01

    Many arable lands have accumulated large reserves of residual phosphorus (P) and a relatively large proportion of soil P is less available for uptake by plants. Root released organic anions are widely documented as a key physiological strategy to enhance P availability, while limited information has been generated on the contribution of rhizosphere organic anions to P utilization by crops grown in agricultural soils that are low in available P and high in extractable Ca, Al, and Fe. We studied the role of rhizosphere organic anions in P uptake from residual P in four common crops Triticum aestivum, Avena sativa, Solanum tuberosum , and Brassica napus in low- and high-P availability agricultural soils from long-term fertilization field trials in a mini-rhizotron experiment with four replications. Malate was generally the dominant organic anion. More rhizosphere citrate was detected in low P soils than in high P soil. B. napus showed 74-103% increase of malate in low P loam, compared with clay loam. A. sativa had the greatest rhizosphere citrate concentration in all soils (5.3-15.2 μmol g -1 root DW). A. sativa also showed the highest level of root colonization by arbuscular mycorrhizal fungi (AMF; 36 and 40%), the greatest root mass ratio (0.51 and 0.66) in the low-P clay loam and loam respectively, and the greatest total P uptake (5.92 mg P/mini-rhizotron) in the low-P loam. B. napus had 15-44% more rhizosphere acid phosphatase (APase) activity, ~0.1-0.4 units lower rhizosphere pH than other species, the greatest increase in rhizosphere water-soluble P in the low-P soils, and the greatest total P uptake in the low-P clay loam. Shoot P content was mainly explained by rhizosphere APase activity, water-soluble P and pH within low P soils across species. Within species, P uptake was mainly linked to rhizosphere water soluble P, APase, and pH in low P soils. The effects of rhizosphere organic anions varied among species and they appeared to play minor roles in

  5. Determination of plant species for the phytoremediation of carbofuran residue in rice field soils

    Directory of Open Access Journals (Sweden)

    Alissara Reungsang

    2005-09-01

    Full Text Available This study searched for plant species suitable for accumulating carbofuran residue in rice field soil. Three groups of plant, i.e. grass crops, upland crops, and vegetable crops, were grown in 8 inches diameter plastic pots filled with soil containing 5 mg/kg carbofuran. Parts of plants (stems and leaves, roots, fruits were harvested at day 120 and analyzed for carbofuran residue using HPLC. The results indicated that Helianthus annuus L. (sunflower was the most suitable species for phytoremediation of carbofuran residue in rice field soil because it highly accumulated carbofuran up to 93.4 μg/kg dry weight in its stems and leaves. In addition, H. annuus L. (sunflower could tolerate carbofuran since it showed similar physical appearance (circumference and height to control not receiving carbofuran.

  6. Assessment of Grewia oppositifolia leaves as crude protein supplement to low-quality forage diets of sheep

    NARCIS (Netherlands)

    Khan, N.A.; Habib, G.

    2012-01-01

    In the tropical arid and semi-arid regions of many developing countries, sheep are predominantly grazed on low-quality pastures and stall-fed on crop residues. This study evaluated the potential of Grewia oppositifolia tree leaves as crude protein (CP) supplement to the low-quality diets of sheep in

  7. Field Measurements of Trace Gases and Aerosols Emitted by Undersampled Combustion Sources Including Wood and Dung Cooking Fires, Garbage and Crop Residue Burning, and Indonesian Peat Fires

    Science.gov (United States)

    Stockwell, C.; Jayarathne, T. S.; Goetz, D.; Simpson, I. J.; Selimovic, V.; Bhave, P.; Blake, D. R.; Cochrane, M. A.; Ryan, K. C.; Putra, E. I.; Saharjo, B.; Stone, E. A.; DeCarlo, P. F.; Yokelson, R. J.

    2017-12-01

    Field measurements were conducted in Nepal and in the Indonesian province of Central Kalimantan to improve characterization of trace gases and aerosols emitted by undersampled combustion sources. The sources targeted included cooking with a variety of stoves, garbage burning, crop residue burning, and authentic peat fires. Trace gas and aerosol emissions were studied using a land-based Fourier transform infrared spectrometer, whole air sampling, photoacoustic extinctiometers (405 and 870nm), and filter samples that were analyzed off-line. These measurements were used to calculate fuel-based emission factors (EFs) for up to 90 gases, PM2.5, and PM2.5 constituents. The aerosol optical data measured included EFs for the scattering and absorption coefficients, the single scattering albedo (at 870 and 405 nm), as well as the absorption Ångström exponent. The emissions varied significantly by source, although light absorption by both brown and black carbon (BrC and BC, respectively) was important for all non-peat sources. For authentic peat combustion, the emissions of BC were negligible and absorption was dominated by organic aerosol. The field results from peat burning were in reasonable agreement with recent lab measurements of smoldering Kalimantan peat and compare well to the limited data available from other field studies. The EFs can be used with estimates of fuel consumption to improve regional emissions inventories and assessments of the climate and health impacts of these undersampled sources.

  8. Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE): Emissions of particulate matter from wood and dung cooking fires, brick kilns, generators, trash and crop residue burning

    Science.gov (United States)

    Stone, Elizabeth; Jayarathne, Thilina; Stockwell, Chelsea; Christian, Ted; Bhave, Prakash; Siva Praveen, Puppala; Panday, Arnico; Adhikari, Sagar; Maharjan, Rashmi; Goetz, Doug; DeCarlo, Peter; Saikawa, Eri; Yokelson, Robert

    2016-04-01

    The Nepal Ambient Monitoring and Source Testing Experiment (NAMASTE) field campaign targeted the in situ characterization of widespread and under-sampled combustion sources. In Kathmandu and the Terai, southern Nepal's flat plains, samples of fine particulate matter (PM2.5) were collected from wood and dung cooking fires (n = 22), generators (n = 2), groundwater pumps (n = 2), clamp kilns (n = 3), zig-zag kilns (n = 3), trash burning (n = 4), one heating fire, and one crop residue fire. Co-located measurements of carbon dioxide, carbon monoxide, and volatile organic compounds allowed for the application of the carbon mass balance approach to estimate emission factors for PM2.5, elemental carbon, organic carbon, and water-soluble inorganic ions. Organic matter was chemically speciated using gas chromatography - mass spectrometry for polycyclic aromatic hydrocarbons, sterols, n-alkanes, hopanes, steranes, and levoglucosan, which accounted for 2-8% of the measured organic carbon. These data were used to develop molecular-marker based profiles for use in source apportionment modeling. This study provides quantitative emission factors for particulate matter and its constituents for many important combustion sources in Nepal and South Asia.

  9. Identification and characterization of an anaerobic ethanol-producing cellulolytic bacterial consortium from Great Basin hot springs with agricultural residues and energy crops.

    Science.gov (United States)

    Zhao, Chao; Deng, Yunjin; Wang, Xingna; Li, Qiuzhe; Huang, Yifan; Liu, Bin

    2014-09-01

    In order to obtain the cellulolytic bacterial consortia, sediments from Great Basin hot springs (Nevada, USA) were sampled and enriched with cellulosic biomass as the sole carbon source. The bacterial composition of the resulting anaerobic ethanol-producing celluloytic bacterial consortium, named SV79, was analyzed. With methods of the full-length 16S rRNA librarybased analysis and denaturing gradient gel electrophoresis, 21 bacteria belonging to eight genera were detected from this consortium. Clones with closest relation to the genera Acetivibrio, Clostridium, Cellulosilyticum, Ruminococcus, and Sporomusa were predominant. The cellulase activities and ethanol productions of consortium SV79 using different agricultural residues (sugarcane bagasse and spent mushroom substrate) and energy crops (Spartina anglica, Miscanthus floridulus, and Pennisetum sinese Roxb) were studied. During cultivation, consortium SV79 produced the maximum filter paper activity (FPase, 9.41 U/ml), carboxymethylcellulase activity (CMCase, 6.35 U/ml), and xylanase activity (4.28 U/ml) with sugarcane bagasse, spent mushroom substrate, and S. anglica, respectively. The ethanol production using M. floridulus as substrate was up to 2.63 mM ethanol/g using gas chromatography analysis. It has high potential to be a new candidate for producing ethanol with cellulosic biomass under anoxic conditions in natural environments.

  10. Influência do tipo e da quantidade de resíduos vegetais associados a herbicidas residuais no desenvolvimento da cultura da soja Influence of the type and amound of crop residues combined with residual herbicides on soybean development

    Directory of Open Access Journals (Sweden)

    Núbia Maria Correia

    2006-01-01

    Full Text Available O objetivo do trabalho foi avaliar, em condições de campo e na região originalmente sob cerrado, os efeitos de resíduos vegetais [sorgo de cobertura (híbrido Cober Exp, milheto forrageiro (var. BN2, capim pé-de-galinha (Eleusine coracana e capim braquiária (Brachiaria brizantha] e duas quantidades de palha (3,0 e 5,5 t ha-1, no primeiro ano do estudo, e 3,5 e 5,8 t ha-1, no segundo, associados a herbicidas residuais (diclosulam a 35 g ha-1 e imazaquin a 140 g ha-1 aplicados em pré-emergência, no desenvolvimento da cultura da soja. Para tal, foi desenvolvido experimento no ano agrícola 2003/2004 e repetido em 2004/2005, na Fazenda Três Marcos, em Uberlândia (MG. No primeiro ano, após a instalação da cultura da soja, plantas de Eleusine coracana tornaram-se as principais infestantes na cobertura de capim pé-de-galinha. Devido à ausência de controle dessa espécie pelos herbicidas testados, a convivência entre ela e a cultura refletiu negativamente nas plantas de soja. O herbicida imazaquin afetou, indiretamente, as plantas de soja, em virtude do seu controle insatisfatório das plantas daninhas. Nas plantas de soja crescidas sobre cobertura de capim braquiária (nos dois anos e de capim pé-de-galinha (no segundo ano observaram-se maior produtividade de grãos, acúmulo de massa e altura de plantas. Os resíduos vegetais de sorgo influenciaram negativamente no desenvolvimento das plantas de soja, nos dois anos. Quanto aos níveis de palha, houve diferença entre eles para milheto forrageiro (no primeiro ano e sorgo (no segundo ano. O menor nível de milheto forrageiro e o maior de sorgo ocasionaram prejuízos às plantas de soja.This work was conducted in the agricultural years 2003/2004 and 2004/2005, at the "Três Marcos" Farm, Uberlândia (MG, Brazil. It was aimed to evaluate the effect of crop residues [coverage sorghum (hybrid Cober Exp, forage millet (var. BN2, finger millet (Eleusine coracana and St. Lucia Grass

  11. Rye cover crop increases earthworm populations and reduces losses of broadcast, fall-applied, fertilizers in surface runoff

    Science.gov (United States)

    Corn (Zea mays L.) silage and soybean [Glycine max (L.) Merr.] rotations in the US Upper Midwest leave minimal amounts of surface residues, which can contribute to soil degradation and a reduction in water quality. Planting cover crops after harvest can reduce these concerns, but their effectiveness...

  12. Mixed crop-livestock production systems of smallholder farmers in sub-humid and semi-arid areas of Zambia

    International Nuclear Information System (INIS)

    Lungu, J.C.N.

    2002-01-01

    Livestock production activities among small-scale farmers of semi-arid (Agro-ecological zone 1) and sub-humid (Agro-ecological zone 2) areas of Zambia are integrated with crop production activities in what is termed as crop/livestock farming system. This is a closed system in which production of one enterprise depends on the other. In Zambia, crop production depends on draught animals for tillage of cropping area, animal manure for fertilisation of crops while livestock depend on crop residues for dry season feeding. Good quality grass is generally available in adequate amounts to support reasonable level of livestock productivity during the rainy season. But livestock rely on low quantity and poor quality, highly fibrous perennial grass from veld and fibrous crop residues during the dry season. These resources are inadequate to support optimum livestock productivity activities. Poor nutrition results in low rates of reproduction and production as well as increased susceptibility to diseases. With the increasing human population cropping land is expanding, leading to increased production of crop residues. This has however, reduced the grazing land available for ruminant production. In Zambia large quantities of crop residues (stovers, husks and straws, legume tops and hulls, sugar cane tops, cassava leaves, potato vines, etc.) are left in the field where they are wasted each year because small-scale farmers lack the knowledge on how best to use them. There is a need to find ways to reverse this situation by adapting known and workable technologies to local conditions and by introducing new approaches for improving the use of crop residues and poor quality fibrous feeds. Efforts should also be made to enlarge feed resource base. The technologies should be simple and effective. In the presence of a dynamic market system, livestock production in a crop/livestock system could be intensified and made profitable for small-scale farmers. (author)

  13. Replacing fallow by cover crops: economic sustainability

    Science.gov (United States)

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

    2013-04-01

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

  14. Sugarcane crop residue and bagasse allelopathic impact on oat (Avena sative L.), morningglory (Ipomoea purpurea L.), and redroot pigweed (Amaranthus retroflexus L.) germination

    Science.gov (United States)

    Allelopathy, the chemical interaction between plants, may result in the inhibition of plant growth and development, and can include compounds released from a crop that adversely impact crop or weed species. The objective of this research was to determine the allelopathic impact of sugarcane (Sacchar...

  15. Glyphosate Mineralization: Effect of Temperature and Soybean and Corn Crop Residues Mineralización de Glifosato: Efecto de la Temperatura y los Residuos Vegetales de Soya y Maíz

    Directory of Open Access Journals (Sweden)

    Ariel Rampoldi

    2008-03-01

    Full Text Available Mineralization is the main mechanism of dissipation of glyphosate herbicide (N-[phosphonomethyl] glycine in soil. However, there is scarce information about the mineralization process in strata formed by stubbles in no-tillage systems. The kinetics and rate of mineralization of herbicide in stubbles of soybean (Glycine max L. Merr. and corn (Zea mays L. were investigated. To evaluate the effect of age of crop residues, samples of soybean stubbles were collected immediately after harvest (Soja 1 and four months after harvest (Soja 2. Corn crop residues were collected three months after harvest. Glyphosate evolution and total microbial activity (TMA were monitored by release of 14C-CO2 and C-CO2 under laboratory conditions with two temperatures, 15 and 28 ºC. Crop residues size was evaluated using grinding (1 mm and cut (1 to 2 cm stubbles. Results showed that glyphosate mineralization was affected by the incubation temperature and the origin and age of crop residues. Size of crop residues did not modify glyphosate mineralization. Average glyphosate mineralization after 56 days of incubation at 15 and 28 ºC was of 3.9 and 9.9%, respectively, of the 14C-glyphosate initially applied. In maize crop residues the percentages were 2.0 and 3.0%, respectively, at 15 and 28 ºC. A similar evolution was detected for TMA. The co-metabolic nature of glyphosate mineralization was corroborated. An inverse relation between C/N ratio and glyphosate mineralization was detected. Higher glyphosate mineralization was detected in fresh soybean stubbles, suggesting that applications on aged crop residues could increase the persistence of glyphosate in no-tillage systemsLa mineralización es el principal mecanismo de disipación del herbicida glifosato (N-[fosfonometil] glicina en el suelo. Existe escasa información sobre el proceso de mineralización de glifosato en el estrato formado por rastrojos en suelos cultivados en sistema de siembra directa. Las muestras de

  16. Nitrogen fixation by groundnut and velvet bean and residual benefit to a subsequent maize crop Fixação de nitrogênio por amendoim e mucuna e benefício residual para uma cultura de milho

    Directory of Open Access Journals (Sweden)

    Ambate Okito

    2004-12-01

    Full Text Available Chemical fertilisers are rarely avaiable to poor farmers, for whom the nitrogen (N is often the most limiting element for cereal grain production. The objective of this study was to quantify the contribution of biological nitrogen fixation (BNF to groundnut (Arachis hypogaea and velvet bean (Mucuna pruriens crops using the 15N natural abundance (delta15N technique and to determine their residual effect and that of a natural fallow, on growth and N accumulation by two rustic maize varieties. The contribution of BNF calculated from delta15N data was 40.9, 59.6 and 30.9 kg ha-1, for groundnut, velvet bean and the natural fallow, respectively. The only legume grain harvested was from the groundnut, which yielded approximately 1.000 kg ha-1. The subsequent maize varieties ("Sol de Manhã" and "Caiana Sobralha" yielded between 1.958 and 2.971 kg ha-1, and were higher after velvet bean for both maize varieties and "Sol da Manhã" groundnut, followed by "Caiana" after groundnut and, finally, the natural fallow. For a small-holder producer the most attractive system is the groundnut followed by maize, as, in this treatment, both groundnut and maize grain harvest are possible. However, a simple N balance calculation indicated that the groundnut-maize sequence would, in the long term, deplete soil N reserves, while the velvet bean-maize sequence would lead to a build up of soil nitrogen.Fertilizantes químicos raramente estão disponíveis aos agricultores com poucos recursos econômicos, e assim o N é, freqüentemente, um elemento mais limitante para a produção de grãos. O objetivo deste trabalho foi quantificar a contribuição da fixação biológica de nitrogênio (FBN às culturas de amendoim (Arachis hypogaea e mucuna (Mucuna pruriens, por meio da técnica de abundância natural de 15N e determinar o efeito residual das leguminosas e do pousio sobre o crescimento e acumulação de N em duas variedades de milho. A contribuição da FBN calculada a

  17. Effect of 3D nitrogen, dry mass per area and local irradiance on canopy photosynthesis within leaves of contrasted heterogeneous maize crops.

    Science.gov (United States)

    Drouet, J-L; Bonhomme, R

    2004-06-01

    Nitrogen partitioning within stands has been described fairly comprehensively, especially for C(3) plants in dense stands where the horizontal heterogeneity of foliage distribution is relatively small. Nitrogen has been shown to be distributed vertically and in parallel to light, maximizing carbon assimilation and stand productivity. Conversely, row crops such as maize (C(4) plants) are characterized by strong horizontal heterogeneity of foliage distribution, and a three-dimensional (3D) approach is required to investigate the combined effect of spatial distribution of nitrogen and light on canopy photosynthesis. The 3D geometry of maize canopies was modelled with varying densities and at different developmental stages using plant digitizing under field conditions. For lamina parts, photosynthesis was measured and nitrogen content per unit area (N(a)) was described from analysis of nitrogen content per unit mass (N(m)) and dry mass per unit area (M(a)). Hyperbolic relationships between photosynthesis at irradiance saturation (P(max)) and N(a) were established as well as a linear relationship between dark respiration (R(d)) and N(a), whereas quantum efficiency (alpha) was found to be independent of N(a). N(m), M(a) and N(a) were shown to change over time vertically (i.e. between laminae), which has been largely reported previously, and horizontally (i.e. within laminae), which has scarcely been described previously. Even if M(a) played a major role in N(a), a strong relationship between N(a) and M(a) could not be demonstrated, whereas several previous studies have found that N(a) was essentially related to M(a) rather than N(m). From simulations of radiative exchange using a 3D volume-based approach and lamina photosynthesis using a hyperbola, it was shown that real patterns of N(a) partitioning could increase daily crop photosynthesis by up to 8 % compared with uniform patterns of N(a), especially for the earliest stages of stand development.

  18. Finnish farmers' willingness to produce and supply biomass from energy crops and forest residues. A survey of landowners' attitudes and intentions

    Energy Technology Data Exchange (ETDEWEB)

    Raemoe, A.-K.; Latvala, T. (Pellervo Economic Research Inst., Helsinki (Finland)), Email: anna-kaisa.ramo@ptt.fi; Silvennoinen, H. (Univ. of Joensuu (Finland)), Email: harri.silvennoinen@joensuu.fi

    2009-07-01

    According to EU's Climate and Energy Plan Finland is obliged to increase the proportion of renewable energy sources considerably by the year 2020. The obligation is challenging and requires among others a considerably increased use of biomass. Besides wood energy crop production provides a considerable potential as energy source in Finland. Farmer forest owners are one of the key groups regarding the supply of field energy crops and energy wood in Finland. Basically, farmers have a positive attitude towards the production of field energy crops and energy wood. Their interest in bio-energy related entrepreneurship has also increased in recent years. However, farmers do not find the business environment of biomass production satisfactory. Still the results indicate that the number of field crop producers would at least double by the year 2012. The increase is, however, considerably less than the estimated potential of recent scenarios. The results also imply that famer forest owners have not any intentions to increase their energy wood supplies in the next few years. This is mainly due to undeveloped energy wood markets and unsatisfactory energy wood prices. In order to enhance the biomass production and supply, both field energy crop and energy wood markets and extension need to be improved to meet farmers' needs. (orig.)

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

    DEFF Research Database (Denmark)

    Eriksen, Jørgen; Askegaard, Margrethe; Rasmussen, Jim

    2015-01-01

    Intensive dairy farming, with grass-arable crop rotations is challenged by low N use efficiency that may have adverse environmental consequences. We investigated nitrate leaching and N fertility effects of grass–clover leys for five years in two organic crop rotations with different grassland...... with the 2-yr-old leaching the most (36–46 kg N ha−1), and (4) high leaching (>50 kg N ha−1) with lupin and maize, where especially maize was consistently high in all five years (average 81 kg N ha−1). Great care should be taken during all phases of the dairy crop rotation where grasslands cause considerable...... build-up of fertility. With due care and the best management practice, nitrate leaching losses may be reduced to low levels....

  20. Suitability of peanut residue as a nitrogen source for a rye cover crop Resíduos da cultura de amendoim como fonte de nitrogênio para uma cultura de cobertura de centeio

    Directory of Open Access Journals (Sweden)

    Kipling Shane Balkcom

    2007-01-01

    Full Text Available Leguminous winter cover crops have been utilized in conservation systems to partially meet nitrogen (N requirements of succeeding summer cash crops, but the potential of summer legumes to reduce N requirements of a winter annual grass, used as a cover crop, has not been extensively examined. This study assessed the N contribution of peanut (Arachis hypogaea L. residues to a subsequent rye (Secale cereale L. cover crop grown in a conservation system on a Dothan sandy loam (fine-loamy, kaolinitic, thermic Plinthic Kandiudults at Headland, AL USA during the 2003-2005 growing seasons. Treatments were arranged in a split plot design, with main plots of peanut residue retained or removed from the soil surface, and subplots as N application rates (0, 34, 67 and 101 kg ha-1 applied in the fall. Peanut residue had minimal to no effect on rye biomass yields, N content, carbon (C /N ratio, or N, P, K, Ca and Zn uptake. Additional N increased rye biomass yield, and N, P, K, Ca, and Zn uptakes. Peanut residue does not contribute significant amounts of N to a rye cover crop grown as part of a conservation system, but retaining peanut residue on the soil surface could protect the soil from erosion early in the fall and winter before a rye cover crop grows sufficiently to protect the typically degraded southeastern USA soils.Culturas leguminosas de inverno tem sido utilizadas em sistemas conservacionistas para suprimento parcial das necessidades de nitrogênio (N de culturas subseqüentes de verão, mas o potencial destas culturas leguminosas de verão no sentido de reduzir as necessidades de N de gramíneas anuais de inverno, utilizadas como culturas de cobertura, ainda não foi extensivamente estudado. Este trabalho avaliou a contribuição dos resíduos de uma cultura de amendoim (Arachis hypogaea L. sobre as necessidades de N de uma cultura subsequente de centeio (Secale cereale L. como cobertura desenvolvida dentro de um sistema conservacionista, em um

  1. How can we improve Mediterranean cropping systems?

    DEFF Research Database (Denmark)

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

    2014-01-01

    In the Mediterranean region, crop productivity and food security are closely linked to the adaptation of cropping systems to multiple abiotic stresses. Limited and unpredictable rainfall and low soil fertility have reduced agricultural productivity and environmental sustainability. For this reason...... the tested interventions, incorporation of crop residues coupled with supplementary irrigation showed a significantly positive effect on crop productivity, yield stability and environmental sustainability....

  2. Crop residue, manure and fertilizer in dryland maize under reduced tillage in northern China: I grain yields and nutrient use efficiencies

    NARCIS (Netherlands)

    Wang, X.B.; Cai, D.X.; Hoogmoed, W.B.; Perdok, U.D.; Oenema, O.

    2007-01-01

    The rapidly increasing population and associated quest for food and feed in China has led to increased soil cultivation and nitrogen (N) fertilizer use, and as a consequence to increased wind erosion and unbalanced crop nutrition. In the study presented here, we explored the long-term effects of

  3. Potential photosynthesis of crop surfaces.

    NARCIS (Netherlands)

    Wit, de C.T.

    1959-01-01

    A formula for calculating the potential photosynthesis of a closed crop surface is proposed, assuming that the leaves of the crop are not arranged in any definite direction. In the Netherlands, values for potential photosynthesis vary from 290 kg. CH2O/ha./day in June to 50 kg./ha./day in December.

  4. Taking Leave?

    CERN Multimedia

    2000-01-01

    Planning a holiday? Then if you're a member of the personnel, you'll need to use the Laboratory's new leave system that will be put in place on 1 October. Leave allocations don't change - you are entitled to just as much holiday as before - but instead of being credited annually, your leave will be credited on a monthly basis, and this information will be communicated on your salary slip. The reason for the change is that with the various new leave schemes such as Recruitment by Saved Leave (RSL) and the Progressive Retirement Programme (PRP), a streamlined procedure was required for dealing with all kinds of leave. In the new system, each member of the personnel will have leave accounts to which leave will be credited monthly from the payroll and debited each time an absence is registered in the CERN Electronic Document Handling system (EDH). Leave balances will appear on monthly pay slips, and full details of leave transactions and balances will be available through EDH at all times. As the leave will be c...

  5. Integrated Palmer Amaranth Management in Glufosinate-Resistant Cotton: I. Soil-Inversion, High-Residue Cover Crops and Herbicide Regimes

    Directory of Open Access Journals (Sweden)

    Michael G. Patterson

    2012-11-01

    Full Text Available A three year field experiment was conducted to evaluate the role of soil-inversion, cover crops and herbicide regimes for Palmer amaranth between-row (BR and within-row (WR management in glufosinate-resistant cotton. The main plots were two soil-inversion treatments: fall inversion tillage (IT and non-inversion tillage (NIT. The subplots were three cover crop treatments: crimson clover, cereal rye and winter fallow; and sub subplots were four herbicide regimes: preemergence (PRE alone, postemergence (POST alone, PRE + POST and a no herbicide check (None. The PRE herbicide regime consisted of a single application of pendimethalin at 0.84 kg ae ha−1 plus fomesafen at 0.28 kg ai ha−1. The POST herbicide regime consisted of a single application of glufosinate at 0.60 kg ai ha−1 plus S-metolachlor at 0.54 kg ai ha−1 and the PRE + POST regime combined the prior two components. At 2 weeks after planting (WAP cotton, Palmer amaranth densities, both BR and WR, were reduced ≥90% following all cover crop treatments in the IT. In the NIT, crimson clover reduced Palmer amaranth densities >65% and 50% compared to winter fallow and cereal rye covers, respectively. At 6 WAP, the PRE and PRE + POST herbicide regimes in both IT and NIT reduced BR and WR Palmer amaranth densities >96% over the three years. Additionally, the BR density was reduced ≥59% in no-herbicide (None following either cereal rye or crimson clover when compared to no-herbicide in the winter fallow. In IT, PRE, POST and PRE + POST herbicide regimes controlled Palmer amaranth >95% 6 WAP. In NIT, Palmer amaranth was controlled ≥79% in PRE and ≥95% in PRE + POST herbicide regimes over three years. POST herbicide regime following NIT was not very consistent. Averaged across three years, Palmer amaranth controlled ≥94% in PRE and PRE + POST herbicide regimes regardless of cover crop. Herbicide regime effect on cotton yield was highly significant; the maximum cotton yield was

  6. Variability of matrix effects in liquid and gas chromatography - mass spectrometry analysis of pesticide residues after QuEChERS sample preparation of different food crops

    Science.gov (United States)

    Gas and liquid chromatography (GC and LC) coupled to sophisticated mass spectrometry (MS) instruments are among the most powerful analytical tools currently available to monitor pesticide residues in food, among other applications. However, both GC-MS and LC-MS are susceptible to matrix effects whi...

  7. Quantifying biological nitrogen fixation of different catch crops, and residual effects of roots and tops on nitrogen uptake in barley using in-situ 15N labelling

    DEFF Research Database (Denmark)

    Li, Xiaoxi; Sørensen, Peter; Li, F C

    2015-01-01

    –46 % in macro-roots (0–18 cm soil). Macro-roots represented 31–50 % of total plant N. LBCCs showed similar capacity for soil N extraction as non-LBCCs. After incorporation of LBCC residues, the dry matter and N yields of spring barley were comparable to the effect of 50 kg N fertilisation ha−1, whereas no extra...

  8. Dinâmica do potássio nos resíduos vegetais de plantas de cobertura no Cerrado Potassium dynamics in crop residues of cover plants in Cerrado

    Directory of Open Access Journals (Sweden)

    José Luiz Rodrigues Torres

    2008-08-01

    Full Text Available A produção de biomassa, a manutenção dos resíduos vegetais sobre o solo e sua posterior decomposição são fatores de grande importância no estudo da ciclagem de nutrientes. Este estudo foi desenvolvido na área experimental do CEFET-Uberaba-MG, onde foram avaliados oito tipos de coberturas vegetais: milheto (Pennisetum americanum sin. tiphoydes, braquiária (Brachiaria brizantha, sorgo-forrageiro (Sorghum bicolor L. Moench, guandu (Cajanus cajan (L. Mill sp., crotalária (Crotalarea juncea, aveia-preta (Avena strigosa Schreb, pousio e área em preparo convencional de solo (testemunha em área de Cerrado, na região do Triângulo Mineiro. Avaliaram-se a fitomassa seca (FS, a decomposição dos resíduos em bolsas de decomposição, e a liberação de K. Utilizou-se um modelo matemático para descrever a decomposição dos resíduos e a liberação de K, e calcularam-se a constante de decomposição (k e o tempo de meia-vida (T½. O milheto, o sorgo e a crotalária foram as coberturas que apresentaram maiores produções de matéria seca. O maior acúmulo de K ocorreu em gramíneas e a maior liberação de K ocorreu no milheto, aveia, braquiária e crotalária nos primeiros 42 dias após manejo, nos dois períodos avaliados. A braquiária apresentou o menor T½ vida e a maior taxa de liberação de K.Crop residue production, plant residue maintenance and their decomposition are important factors in the understanding of nutrient recycling process. To evaluate K accumulation and release a study with eight cover crops types was developed: pearl millet (Pennisetum americanum sin. tiphoydes, brachiaria grass (Brachiaria brizantha, sorghum (Sorghum bicolor L. Moench, pigeonpea (Cajanus cajan (L. Millsp, sunn hemp (Crotalarea juncea and black oats (Avena strigosa Schreb, fallow land and conventional culture (control in the experimental area of CEFET-Uberaba-MG, in a Cerrado area. The dry mass production, crop residue decomposition in litter bags

  9. Fitomassa e decomposição de resíduos de plantas de cobertura puras e consorciadas Biomass and decomposition of cover crop residues in monoculture and intercropping

    Directory of Open Access Journals (Sweden)

    Alexandre Doneda

    2012-12-01

    for cover crop species in consortium. The experiment was conducted in Não-Me-Toque, RS, on an Oxisol, evaluating nine treatments of four cover crops in monoculture [rye (Secale cereale L., oat (Avena strigosa Schreb, pea (Pisum sativum subsp. arvense, and wild radish (Raphanus sativus L. var. oleiferus Metzg] and five in intercropping [(rye + pea, radish + rye, oat + radish, rye + vetch (Vicia sativa L. and oat + vetch]. The decomposition dynamics of cover crop residues was evaluated in litter bags which were distributed on the soil surface and collected after seven, 14, 21, 28, 57, 117, and 164 days. Leguminous and cruciferous intercropped with Gramineae species resulted in greater biomass production compared to cultivation in monoculture. The nitrogen (N accumulated in the pea and wild radish plants intercropped with rye and oat was similar to the N in the leguminous and cruciferous monocultures and exceeded the N values observed for the Gramineae species in monoculture by 220.4 %. By intercropping cover crops it was possible to reduce the decomposition rate of crop residues compared to the monoculture of leguminous and cruciferous species.

  10. Envelhecimento de resíduos vegetais sobre o solo e os reflexos na eficácia de herbicidas aplicados em pré-emergência Crop residues aging on soil and their effects on pre-emergence herbicides

    Directory of Open Access Journals (Sweden)

    Núbia Maria Correia

    2007-01-01

    Full Text Available Com o objetivo de avaliar os efeitos do envelhecimento dos resíduos vegetais de diferentes espécies [sorgo de cobertura (Sorghum bicolor x S. sudanensis 'Cober Exp', milheto forrageiro (Pennisetum americanum 'BN2', capim-pé-de-galinha (Eleusine coracana e capim-braquiária (Brachiaria brizantha], no controle de Ipomoea grandifolia, pelos herbicidas diclosulam e imazaquin, aplicados em pré-emergência, foi desenvolvido experimento em casa de vegetação, no período de agosto a dezembro de 2004. Foram realizadas determinações químicas nos materiais vegetais em decomposição. A eficácia do herbicida diclosulam não foi afetada pelo envelhecimento da palha de nenhuma das coberturas estudadas. Pelo contrário, a associação desse herbicida a qualquer dos resíduos vegetais estudados, principalmente o de capim-braquiária, favoreceu o controle da planta daninha. O imazaquin teve o potencial de controle influenciado pelas coberturas de milheto forrageiro e capim-braquiária, aos 90 dias após a deposição dos resíduos vegetais sobre o solo. Tal comportamento pode ser atribuído ao enriquecimento de celulose e lignina nos materiais vegetais de milheto forrageiro e capim braquiária.An experiment was conducted from August to December 2004 under greenhouse conditions to evaluate the effects of aging residues of different plant species [coverage sorghum (Sorghum bicolor x S. sudanensis 'Cober Exp', forage millet (Pennisetum americanum 'BN2', finger millet (Eleusine coracana and St. Lucia Grass (Brachiaria brizantha], on the control of Ipomoea grandifolia using the pre-emergence herbicides diclosulam and imazaquin. Crop residues were subjected to chemical analyses. The efficiency of diclosulam was not affected by any of the residues. On the other hand, in association with residues of any of the species, but especially with St. Lucia Grass, this herbicide showed increased weed control efficiency. The control potential of imazaquin was influenced

  11. Residues of sugar cane crop and its effects on the epigeic invertebrate faunaResíduos da cultura da cana-de-açúcar e seus efeitos sobre a fauna invertebrada epigéica

    Directory of Open Access Journals (Sweden)

    Júlio César Salton

    2011-08-01

    Full Text Available This study aimed to evaluate the effect of the availability of sugar cane residues on the epigeic invertebrate fauna. The evaluations were made after cane sugar harvest f, considering three levels of residues: 0% (total removal of residues from the soil surface, 50% (removal of half of the waste in the plots, the dry mass of 7.6 Mg ha-1 and 100% (keeping track of residues produced, dry mass of 16.9 Mg ha-1. A fragment of native vegetation in the region, located close to the sugar cane crop, was evaluated for comparison. The experimental plots were arranged in a randomized block design with eight replications. Each plot consisted of five rows 20 m long, were installed two pitfalls to capture the invertebrate fauna, representing sixteen traps in each treatment, totaling forty-eight throughout the experiment. The organisms were extracted manually and identified at major taxonomic groups. The highest diversity and groups richness of epigeic invertebrate fauna were observed in the cane sugar crop with the maintenance of the surface residues (100 and 50%. Moreover, complete removal of residues from the soil surface promoted a significant reduction of the soil invertebrates organisms. Soil samples were collected for evaluation of chemical attributes. The organisms of epigeic invertebrate fauna showed sensitive in detecting changes in systems, depending on the maintenance of plant residues of sugar cane.O presente estudo teve como objetivo avaliar o efeito da disponibilidade de resíduos de cana-de-açúcar sobre a fauna invertebrada epigéica. As avaliações foram realizadas após a colheita da cana-de-açúcar, considerando três níveis de resíduos: 0 % (retirada total de resíduos da superfície do solo, 50 % (retirada da metade dos resíduos nas parcelas, massa seca de 7,6 Mg ha-1 e 100 % (manutenção completa dos resíduos produzidos, massa seca de 16,9 Mg ha-1. As parcelas experimentais foram dispostas num delineamento em blocos casualizados

  12. Direct and residual effect of rockphosphate with amendments on growth and uptake of P by mustard and moong crops grown in Typic Ustochrept

    International Nuclear Information System (INIS)

    Dravid, M.S.

    2000-01-01

    A considerable increase in drymatter accumulation and total phosphorus uptake by mustard was observed with the addition of partially acidulated rockphosphate (PARP) and rockphosphate (RP) pre-decomposed with biogas slurry treatments as compared to other combinations, while in case of moong RP amended with pyrite followed by PARP exhibited marked increase in yield and assimilation of P over the other treatments. The differences between control and rockphosphate or pyrite alone were significant in both the crops. The percent Pdff and its utilization from rockphosphate were highest under partially acidulated rockphosphate treatment. Among the different amendments, the performance of biogas slurry was superior to the pyrite and P solubiliser with respect to the Pdff and P utilization from rockphosphate. The available P in soil was depressed drastically after mustard, but it improved again after moong. (author)

  13. Cross-Contamination of Residual Emerging Contaminants and Antibiotic Resistant Bacteria in Lettuce Crops and Soil Irrigated with Wastewater Treated by Sunlight/H2O2.

    Science.gov (United States)

    Ferro, Giovanna; Polo-López, María I; Martínez-Piernas, Ana B; Fernández-Ibáñez, Pilar; Agüera, Ana; Rizzo, Luigi

    2015-09-15

    The sunlight/H2O2 process has recently been considered as a sustainable alternative option compared to other solar driven advanced oxidation processes (AOPs) in advanced treatment of municipal wastewater (WW) to be reused for crop irrigation. Accordingly, in this study sunlight/H2O2 was used as disinfection/oxidation treatment for urban WW treatment plant effluent in a compound parabolic collector photoreactor to assess subsequent cross-contamination of lettuce and soil by contaminants of emerging concern (CECs) (determined by QuEChERS extraction and LC-QqLIT-MS/MS analysis) and antibiotic resistant (AR) bacteria after irrigation with treated WW. Three CECs (carbamazepine (CBZ), flumequine (FLU), and thiabendazole (TBZ) at 100 μg L(-1)) and two AR bacterial strains (E. coli and E. faecalis, at 10(5) CFU mL(-1)) were spiked in real WW. A detection limit (DL) of 2 CFU mL(-1) was reached after 120 min of solar exposure for AR E. coli, while AR E. faecalis was more resistant to the disinfection process (240 min to reach DL). CBZ and TBZ were poorly removed after 90 min (12% and 50%, respectively) compared to FLU (94%). Lettuce was irrigated with treated WW for 5 weeks. CBZ and TBZ were accumulated in soil up to 472 ng g(-1) and 256 ng g(-1) and up-taken by lettuce up to 109 and 18 ng g(-1), respectively, when 90 min treated WW was used for irrigation; whereas no bacteria contamination was observed when the bacterial density in treated WW was below the DL. A proper treatment time (>90 min) should be guaranteed in order to avoid the transfer of pathogens from disinfected WW to irrigated crops and soil.

  14. Simultaneous determination of residues of emamectin and its metabolites, and milbemectin, ivermectin, and abamectin in crops by liquid chromatography with fluorescence detection.

    Science.gov (United States)

    Yoshii, K; Kaihara, A; Tsumura, Y; Ishimitsu, S; Tonogai, Y

    2001-01-01

    A liquid chromatographic (LC) method was developed for the determination of emamectin and its metabolites (8,9-Z-isomer, N-demethylated, N-formylated, and N-methylformylated emamectin) in various crops. The analytes were extracted with acetone, cleaned up on cartridge columns (C18 and NH2), derivatized with trifluoroacetic anhydride and 1-methylimidazole, and determined by LC with fluorescence detection. Because radish inhibited the formation of the fluorescent derivatives, an additional Bond Elut PRS cartridge was used in the cleanup of Japanese radish samples. During sample preparation, N-formylated emamectin partially degraded to emamectin B1b and emamectin B1a, and the 8,9-Z-isomer partially degraded to N-demethylated emamectin. Therefore, emamectin and its metabolites were determined as total emamectin, i.e., their sum was estimated as emamectin benzoate. Their recoveries from most crops were approximately 80-110% with the developed method. The detection limits for the analytes in vegetables were 0.1-0.3 parts per trillion (ppt). The results for these compounds were confirmed by LC/mass spectrometry (LC/MS; electrospray ionization mode). Because the fluorescent derivative of emamectin was undetectable by LC/MS, the results for the analyte were confirmed by using a sample solution without derivatization. Limits of detection by LC/MS were similar to the fluorescence detection limits, 0.1-0.3 ppt in vegetables. In addition to the emamectins, milbemectin, ivermectin, and abamectin were also determined by the developed method.

  15. Decomposição de resíduos vegetais em latossolo sob cultivo de milho e plantas de cobertura Decomposition of plant residues in latosol under corn crop and cover crops

    Directory of Open Access Journals (Sweden)

    Arminda Moreira de Carvalho

    2008-12-01

    .Soil degradation occurs as a consequence of intensive preparation associated with monocropping systems with deposition of residues that are rapidly decomposed. The objective of this study was to investigate the decomposition rates of different cover plants residues in Latosol (Oxisol under conventional and no-tillage systems. The cover plants (Crotalaria juncea, Canavalia brasiliensis, Cajanus cajan, Mucuna pruriens, Helianthus annuus, Pennisetum glaucum, Raphanus sativus and natural fallow, as a control were used in a succession with maize. The cover plants were cut when flowering reached approximately 50 % and remained on the soil until the sowing of the maize. In the conventional system, plant residues were incorporated in subplots with plough. Litter bags with 10 g of dry matter of each species were placed on the soil surface and covered with plant residues to determine the decomposition rate along the dry (60 and 90 days of incubation and wet seasons (180, 210 and 240 days of incubation under both systems. During soil preparation and herbicide application before the sowing of maize, the remaining bags were removed from the field and kept in cold storage (0 ºC. After the sowing of maize, these bags were returned to the respective subplots, either on the surface for the no-tillage treatment or buried at 10 cm depth when under the incorporation treatment. The lowest decomposition rates were found for residues of Cajanus cajan Pennisetum glaucum, Mucuna pruriens, and natural fallow. Incorporation of plant residues accelerated the decomposition time, when compared to no-tillage system, except for Raphanus sativus. Maize yield was highest after the rotation with Canavalia brasiliensis.

  16. The Impact of Post Harvest Agricultural Crop Residue Fires on Volatile Organic Compounds and Formation of Secondary Air Pollutants in the N.W. Indo-Gangetic Plain

    Science.gov (United States)

    Sinha, V.; Chandra, P.; Kumar, V.; Sarkar, C.

    2015-12-01

    The N.W. Indo-Gangetic Plain (IGP) is an agriculturally and demographically important region of the world. Every year during the post harvest months of April-May and October-November, large scale open burning of wheat straw and paddy straw occurs in the region impairing the regional air quality and resulting in air pollution episodes. Here, using online in-situ measurements from the IISER Mohali Atmospheric Chemistry Facility (Sinha et al., Atmos Chem Phys, 2014), which is located at a regionally representative suburban site in the agricultural state of Punjab, India, we investigated the effects of this activity on gas phase chemistry. The online data pertaining to the pre harvest and post harvest paddy residue fires in 2012, 2013 and 2014 were analyzed to understand the effect of this anthropogenic activity on atmospheric chemistry and regional air quality with respect to health relevant VOCs such as benzenoids and isocyanic acid and trace gases such as ozone and carbon monoxide. These compounds showed marked increases (factor of 2-3 times higher) in their concentrations which correlated with the biomass combustion tracers such as acetonitrile. Emissions from the paddy residue fires did not result in significant enhancement of ambient ozone in 2012 but instead sustained hourly daytime ozone concentrations at ~ 50 ppb during the late post monsoon season, despite decreases in solar radiation and temperature. Results of such massive perturbations to ambient chemical composition, reactivity and formation of secondary pollutants and its implications for human health will be presented in this paper.

  17. Detoxification of Olive Mill Wastewater and Bioconversion of Olive Crop Residues into High-Value-Added Biomass by the Choice Edible Mushroom Hericium erinaceus.

    Science.gov (United States)

    Koutrotsios, Georgios; Larou, Evangelia; Mountzouris, Konstantinos C; Zervakis, Georgios I

    2016-09-01

    Environmentally acceptable disposal of olive cultivation residues (e.g., olive prunings; olive pruning residues (OLPR)) and olive mill wastes is of paramount importance since they are generated in huge quantities within a short time. Moreover, olive mill wastewater (OMW) or sludge-like effluents ("alperujo"; two-phase olive mill waste (TPOMW)) are highly biotoxic. Hericium erinaceus is a white-rot fungus which produces choice edible mushrooms on substrates rich in lignocellulosics, and its suitability for the treatment of olive by-products was examined for the first time. Fungal growth resulted in a notable reduction of OMW's pollution parameters (i.e., 65 % decolorization, 47 % total phenolic reduction, and 52 % phytotoxicity decrease) and correlated with laccase and manganese peroxidase activities. Solid-state fermentation of various mixtures of OLPR, TPOMW, and beech sawdust (control) by H. erinaceus qualified OLPR in subsequent cultivation experiments, where it exhibited high mushroom yields and biological efficiency (31 %). Analyses of proximate composition and bioactive compound content revealed that mushrooms deriving from OLPR substrates showed significantly higher crude fat, total glucan, β-glucan, total phenolics, and ferric-reducing antioxidant potential values than the control. H. erinaceus demonstrated the potential to detoxify OMW and bioconvert OLPR into high-quality biomass, and hence, this fungus could be successfully exploited for the treatment of such by-products.

  18. Possible Appearance of Degradation Products of Paraquat in Crops

    Energy Technology Data Exchange (ETDEWEB)

    Slade, P. [Imperial Chemical Industries LTD., Jealott' s Hill Research Station, Bracknell, Berks. (United Kingdom)

    1966-05-15

    Chemical analysis has established that residue levels of paraquat in crops harvested after use of the chemical are at such a low level as to constitute no hazard to the consuming public. (Paraquat dichloride is 1,1'-dimethyl-4,4'-bipyridylium dichloride). There remained the possibility that toxic metabolites or other conversion products of paraquat might appear in crops. This paper is concerned with attempts to evaluate this possibility, and demonstrates that no hazard arises from the formation of degradation products. It has been shown, using paraquat labelled with {sup 14}C in the methyl groups and in the pyridine nuclei, that the chemical is not metabolically degraded in plants. However, photochemical degradation of paraquat can occur on the surface of leaves in sunlight. In vitro experiments involving ultra-violet irradiation of aqueous solutions of {sup 14}C-paraquat have shown that 4-carboxy-1-methylpyridinium chloride and methylamine hydrochloride are the only products formed in significant amount in the photochemical degradation. Paper chromatography and isotope dilution have shown that these products are formed on leaves of plants treated with {sup 14}C-paraquat (mostly after the plants are dead). Whole plant radioautography has established that 4-carboxy-1-{sup 14}C methylpyridinium chloride is not translocated at all from the dead leaves on which it is formed and certainly this compound will not appear in harvested crops. This has been confirmed in an experiment in which {sup 14}C-paraquat was used to desiccate the tops of potato plants before harvesting the tubers. All the radioactivity subsequently found in the tubers could be accounted for as paraquat (level 0.08 ppm). There was no evidence for the presence of significant amounts of other radioactive compounds in the tubers, even though chromatography of extracts of the desiccated plants showed that photochemical degradation products were formed on the leaves: these were not translocated into the

  19. Redução da infestação de Brachiaria plantaginea em soja pela cobertura do solo com palha de aveia-preta Reduction of Brachiaria plantaginea infestation on soybean crop with black oat residues

    Directory of Open Access Journals (Sweden)

    GIOVANI THEISEN

    2000-04-01

    infestation occurred on the crop row than between the rows. In the weed-free treatments, soybean yield was not affected by crop residues. On the other hand, soybean yield increased linearly with increased amount of black oat residues on the soil controlling the weed. In weedy areas, soybean yield increased at the rate of 158 kg/ha for each ton of straw on the soil surface.

  20. Alternative crops

    International Nuclear Information System (INIS)

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

    1992-01-01

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

  1. Cover crop and CO2 emissions

    Science.gov (United States)

    Agricultural land management practices account for about 50% of soil organic carbon (SOC) loss. Restoring SOC is important to soil productivity and fertility. Management strategies to rebuild SOC include addition of manure or other organic amendments, increasing root biomass from crops, leaving crop...

  2. ESTIMATION OF THE BURDEN OF PESTICIDE RESIDUES IN SLOVAK POPULATION

    Directory of Open Access Journals (Sweden)

    Jozef Sokol

    2010-07-01

    Full Text Available Pesticides used in the agriculture have to be applied according to the requirements of good agricultural practice and appropriate law. Pesticides leave detectable residues in agricultural crops, raw materials and ecosystem components. Pesticides reach the human population through the food chain. Information on the type and concentration of pesticide residues in food is in Slovakia collected trough the monitoring programs. Health risks associated with pesticides contaminants in human nutrition are very important and are recently studied by several expert groups. Prerequisite programs are necessary to protect public health. Risk analysis and monitoring of the population burden by pesticide contaminants have to be performed in expert level. The general strategy for assessment of toxicity of pesticides is listed by the World health Organisation. Scientific risk assessment is the basis for taking action and making the legislation at national and European community level.doi:10.5219/69

  3. Characterizing pesticide dissipation in food crops

    DEFF Research Database (Denmark)

    Fantke, Peter; Juraske, R.; Jolliet, O.

    2013-01-01

    Ingestion of residues via consumption of food crops is the predominant exposure route of the general population toward pesticides. However, pesticide dissipation in crops constitutes a main source of uncertainty in estimating residues in harvested crop parts and subsequent human exposure. Neverth......Ingestion of residues via consumption of food crops is the predominant exposure route of the general population toward pesticides. However, pesticide dissipation in crops constitutes a main source of uncertainty in estimating residues in harvested crop parts and subsequent human exposure....... Nevertheless, dissipation is a key mechanism in models assessing pesticide distribution in the cropenvironment and the magnitude of residues in harvest. We provide a consistent framework for characterizing pesticide dissipation in food crops for use in modeling approaches applied in health risk and impact...... degradation is dominating. We are currently testing the regression to predict degradation half-lives in crops. By providing mean degradation half-lives at 20°C for more than 300 pesticides, we reduce uncertainty and improve assumptions in current practice of health risk and impact assessments....

  4. Pesticide residue quantification analysis by hyperspectral imaging sensors

    Science.gov (United States)

    Liao, Yuan-Hsun; Lo, Wei-Sheng; Guo, Horng-Yuh; Kao, Ching-Hua; Chou, Tau-Meu; Chen, Junne-Jih; Wen, Chia-Hsien; Lin, Chinsu; Chen, Hsian-Min; Ouyang, Yen-Chieh; Wu, Chao-Cheng; Chen, Shih-Yu; Chang, Chein-I.

    2015-05-01

    Pesticide residue detection in agriculture crops is a challenging issue and is even more difficult to quantify pesticide residue resident in agriculture produces and fruits. This paper conducts a series of base-line experiments which are particularly designed for three specific pesticides commonly used in Taiwan. The materials used for experiments are single leaves of vegetable produces which are being contaminated by various amount of concentration of pesticides. Two sensors are used to collected data. One is Fourier Transform Infrared (FTIR) spectroscopy. The other is a hyperspectral sensor, called Geophysical and Environmental Research (GER) 2600 spectroradiometer which is a batteryoperated field portable spectroradiometer with full real-time data acquisition from 350 nm to 2500 nm. In order to quantify data with different levels of pesticide residue concentration, several measures for spectral discrimination are developed. Mores specifically, new measures for calculating relative power between two sensors are particularly designed to be able to evaluate effectiveness of each of sensors in quantifying the used pesticide residues. The experimental results show that the GER is a better sensor than FTIR in the sense of pesticide residue quantification.

  5. Lead concentration and allocation in vegetable crops grown in a soil contaminated by battery residues Teores e alocação de chumbo em hortaliças cultivadas em solo contaminado por resíduos de baterias

    Directory of Open Access Journals (Sweden)

    Francisco de S Lima

    2009-09-01

    Full Text Available Lead (Pb is a very stable metal in soil and is highly toxic to humans and animals. Exposure to Pb occurs via inhalation of particles from industry and soil, as well as household dust, water, and contaminated food. A greenhouse experiment was carried out to evaluate Pb contents and allocation in vegetable crops grown in a soil contaminated by battery recycling wastes. Eight plant species were studied: tomato, sweet pepper, beet, carrot, cabbage, green collards, eggplant, and okra. The experiment was set up in blocks at random with four replicates. The results showed that carrot, green collards, beet, and okra were the most Pb tolerant species, while the others were very Pb-sensitive, since they did not complete their cycle. The decreasing order for Pb accumulation in the vegetables crops was: carrot > okra > tomato > eggplant > sweet pepper > green collards > cabbage > beet. Taking into account the Pb allocation in plants, the order was: root > stems > leaves > edible parts. Although carrot translocated the lowest Pb amount into the edible part, such level exceeded the legal limit.O chumbo (Pb é um elemento extremamente estável no solo e altamente tóxico para seres humanos e animais. A contaminação com chumbo geralmente ocorre pela exposição decorrente da inalação de partículas oriundas de indústrias ou do solo, ou ainda, pela ingestão de poeira doméstica, água e alimentos de origem animal e vegetal contaminados. O presente trabalho objetivou avaliar os teores e a alocação de Pb em hortaliças cultivadas em solo contaminado com resíduos de reciclagem de baterias. O experimento foi conduzido em casa-de-vegetação com delineamento experimental em blocos casualizados, com quatro repetições. Os tratamentos corresponderam a oito hortaliças: tomate, pimentão, beterraba, cenoura, repolho, couve manteiga, berinjela e quiabo. Os resultados mostraram que as espécies mais tolerantes ao Pb foram cenoura, couve-manteiga, beterraba e

  6. Practicability of Lignocellulosic Waste Composite in Controlling Air Pollution from Leaves Litter through Bioethanol Production

    Science.gov (United States)

    Tarrsini, Mahadevan; Teoh, Yi Peng; Ng, Qi Hwa; Kunasundari, Balakrishnan; Xian Ooi, Zhong; Siew Shuit, Hoong; Hoo, Peng Yong

    2018-03-01

    Environmental degradation through greenhouse emission have spurred nation’s interest on feedstock-based fuel. Yet, development of this clean biofuel is obstructed by the expensive feedstock which takes up most of the production cost. Therefore, as an alternative, utilization of widely available lignocellulosic residues with relatively no commercial significance has been considered. This present work emphasizes on mango (Mangifera indica) leaves one of the most abundant lignocellulosic waste in Malaysia. Through implementation of this biomass for bioethanol production, continuous allowance of air pollution with a deleterious impact to the country’s environment could be reduced. The high concentration of sugar (16-18%w/v) in the form of cellulose and hemicellulose is ultimately the reason behind the selection of these leaves as a substrate for bioethanol production. Hence, in this study, a comparison of biomass composition in Harum Manis, Sunshine and Chokanan mango leaves were conducted to detect the most suitable substrate source to produce biofuel. At the end of the biomass evaluation, Harum Manis mango leaves turned out to be the most competitive bioethanol crop as these leaves reported to be made up of 34.71% cellulose and 44.02% hemicellulose which summed up to give highest fermentable sugar source with a lignin content of 19.45%.

  7. Canaryseed Crop

    Directory of Open Access Journals (Sweden)

    Maximiliano Cogliatti

    2012-03-01

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

  8. Identification and discrimination of herbicide residues using a conducting polymer electronic nose

    Science.gov (United States)

    Alphus Dan Wilson

    2016-01-01

    The identification of herbicide residues on crop foliage is necessary to make crop-management decisions for weed pest control and to monitor pesticide residue levels on food crops. Electronic-nose (e-nose) methods were tested as a cheaper, alternative means of discriminating between herbicide residue types (compared with conventional chromatography methods), by...

  9. A forma de aplicação da uréia e dos resíduos vegetais afeta a disponibilidade de nitrogênio The addition form of crop residues and urea interfers on nitrogen availability

    Directory of Open Access Journals (Sweden)

    Paulo Roberto Ernani

    2005-04-01

    Full Text Available O método de aplicação dos resíduos vegetais e dos fertilizantes nitrogenados pode afetar as reações do nitrogênio no solo, principalmente no plantio direto. O presente trabalho objetivou avaliar esses efeitos na disponibilidade de N para o milho em dois solos, em casa-de-vegetação. Combinações de métodos (ausência, incorporada ou na superfície de adição de palha de aveia (0,4kg m-2 e uréia (50mg N kg-1 foram aplicadas em unidades experimentais (7dm³ vaso-1 de dois solos, perfazendo um fatorial 3 x 3 x 2. O milho foi semeado no dia da aplicação dos tratamentos e as plantas foram cultivadas durante trinta dias, sobre um Neossolo e um Nitossolo, respectivamente com 50 e 520g kg-1 de argila e 8 e 48g kg-1 de matéria orgânica. A aplicação de palha de aveia, principalmente sobre a superfície do solo, beneficiou o desenvolvimento das plantas, possivelmente pela manutenção de maior quantidade de umidade nos solos. A aplicação de uréia não afetou nenhum parâmetro vegetal no solo argiloso, talvez porque a decomposição da matéria orgânica liberou mais N do que a imobilização ocasionada durante a decomposição da palha; no solo arenoso, entretanto, a uréia foi benéfica quando incorporada ao solo, e prejudicial quando adicionada na superfície, provavelmente devido à toxidez de amônia. Dessa forma, o efeito da decomposição da palha de aveia na disponibilidade de N foi função do teor de matéria orgânica original do solo.Management of both crop residues and nitrogen fertilizers affects soil N reactions especially on no-till systems. The magnitude of these effects on N availability to maize was evaluated in a greenhouse study. Combinations of oat straw and urea (absence, soil incorporated or surface applied were added to experimental units (7-dm³ per pot of two soils, in a 3 x 3 x 2 factorial combination. Plants were sown just following treatments addition, and grown for thirty days in two soils (Typic

  10. Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE): emissions of trace gases and light-absorbing carbon from wood and dung cooking fires, garbage and crop residue burning, brick kilns, and other sources

    Science.gov (United States)

    Stockwell, Chelsea E.; Christian, Ted J.; Goetz, J. Douglas; Jayarathne, Thilina; Bhave, Prakash V.; Praveen, Puppala S.; Adhikari, Sagar; Maharjan, Rashmi; DeCarlo, Peter F.; Stone, Elizabeth A.; Saikawa, Eri; Blake, Donald R.; Simpson, Isobel J.; Yokelson, Robert J.; Panday, Arnico K.

    2016-09-01

    The Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE) campaign took place in and around the Kathmandu Valley and in the Indo-Gangetic Plain (IGP) of southern Nepal during April 2015. The source characterization phase targeted numerous important but undersampled (and often inefficient) combustion sources that are widespread in the developing world such as cooking with a variety of stoves and solid fuels, brick kilns, open burning of municipal solid waste (a.k.a. trash or garbage burning), crop residue burning, generators, irrigation pumps, and motorcycles. NAMaSTE produced the first, or rare, measurements of aerosol optical properties, aerosol mass, and detailed trace gas chemistry for the emissions from many of the sources. This paper reports the trace gas and aerosol measurements obtained by Fourier transform infrared (FTIR) spectroscopy, whole-air sampling (WAS), and photoacoustic extinctiometers (PAX; 405 and 870 nm) based on field work with a moveable lab sampling authentic sources. The primary aerosol optical properties reported include emission factors (EFs) for scattering and absorption coefficients (EF Bscat, EF Babs, in m2 kg-1 fuel burned), single scattering albedos (SSAs), and absorption Ångström exponents (AAEs). From these data we estimate black and brown carbon (BC, BrC) emission factors (g kg-1 fuel burned). The trace gas measurements provide EFs (g kg-1) for CO2, CO, CH4, selected non-methane hydrocarbons up to C10, a large suite of oxygenated organic compounds, NH3, HCN, NOx, SO2, HCl, HF, etc. (up to ˜ 80 gases in all). The emissions varied significantly by source, and light absorption by both BrC and BC was important for many sources. The AAE for dung-fuel cooking fires (4.63 ± 0.68) was significantly higher than for wood-fuel cooking fires (3.01 ± 0.10). Dung-fuel cooking fires also emitted high levels of NH3 (3.00 ± 1.33 g kg-1), organic acids (7.66 ± 6.90 g kg-1), and HCN (2.01 ± 1.25 g kg-1), where the latter could

  11. Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE: emissions of trace gases and light-absorbing carbon from wood and dung cooking fires, garbage and crop residue burning, brick kilns, and other sources

    Directory of Open Access Journals (Sweden)

    C. E. Stockwell

    2016-09-01

    Full Text Available The Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE campaign took place in and around the Kathmandu Valley and in the Indo-Gangetic Plain (IGP of southern Nepal during April 2015. The source characterization phase targeted numerous important but undersampled (and often inefficient combustion sources that are widespread in the developing world such as cooking with a variety of stoves and solid fuels, brick kilns, open burning of municipal solid waste (a.k.a. trash or garbage burning, crop residue burning, generators, irrigation pumps, and motorcycles. NAMaSTE produced the first, or rare, measurements of aerosol optical properties, aerosol mass, and detailed trace gas chemistry for the emissions from many of the sources. This paper reports the trace gas and aerosol measurements obtained by Fourier transform infrared (FTIR spectroscopy, whole-air sampling (WAS, and photoacoustic extinctiometers (PAX; 405 and 870 nm based on field work with a moveable lab sampling authentic sources. The primary aerosol optical properties reported include emission factors (EFs for scattering and absorption coefficients (EF Bscat, EF Babs, in m2 kg−1 fuel burned, single scattering albedos (SSAs, and absorption Ångström exponents (AAEs. From these data we estimate black and brown carbon (BC, BrC emission factors (g kg−1 fuel burned. The trace gas measurements provide EFs (g kg−1 for CO2, CO, CH4, selected non-methane hydrocarbons up to C10, a large suite of oxygenated organic compounds, NH3, HCN, NOx, SO2, HCl, HF, etc. (up to ∼ 80 gases in all. The emissions varied significantly by source, and light absorption by both BrC and BC was important for many sources. The AAE for dung-fuel cooking fires (4.63 ± 0.68 was significantly higher than for wood-fuel cooking fires (3.01 ± 0.10. Dung-fuel cooking fires also emitted high levels of NH3 (3.00 ± 1.33 g kg−1, organic acids (7.66 ± 6.90 g kg−1, and HCN

  12. Using Winter Annual Cover Crops in a Virginia No-till Cotton Production System

    OpenAIRE

    Daniel, James B. II

    1997-01-01

    Cotton (Gossypium hirsutum L.) is a low residue crop, that may not provide sufficient surface residue to reduce erosion and protect the soil. A winter annual cover crop could alleviate erosion between cotton crops. Field experiments were conducted to evaluate selected winter annual cover crops for biomass production, ground cover, and N assimilation. The cover crop treatments were monitored under no-till and conventional tillage systems for the effects on soil moisture, cotton yield and qu...

  13. Effects of crop sanitation on banana weevil, Cosmopolites sordidus (Germar) (Coleoptera : Curculionidae), populations and crop damage in Uganda

    NARCIS (Netherlands)

    Masanza, M.; Gold, C.S.; Huis, van A.; Ragama, P.E.

    2006-01-01

    Crop sanitation, i.e. destruction of crop residues, has been hypothesized to lower banana weevil damage by removing adult refuges and breeding sites. Although it has been widely recommended to farmers, limited data are available to demonstrate the efficacy of this method. The effects of crop

  14. Assessment of Grewia oppositifolia leaves as crude protein supplement to low-quality forage diets of sheep.

    Science.gov (United States)

    Khan, Nazir Ahmad; Habib, Ghulam

    2012-10-01

    In the tropical arid and semi-arid regions of many developing countries, sheep are predominantly grazed on low-quality pastures and stall-fed on crop residues. This study evaluated the potential of Grewia oppositifolia tree leaves as crude protein (CP) supplement to the low-quality diets of sheep in comparison with cottonseed cake (CSC). Changes in the chemical composition of the leaves with progressive maturation (December to March) were studied. The leaves maintained a high CP content (>164 g/kg dry matter (DM)) during the prolonged maturation in the winter feed scarcity period. The leaves were rich in Ca (41 g/kg DM) and K (89 g/kg DM). The rate of degradation and effective degradability of CP were consistently higher (P < 0.001) in CSC than in G. oppositifolia. A balance trial in a 4 × 4 Latin square design with four mature Ramghani wethers showed that DM intake, DM and CP digestibility, and N retention did not differ with the substitution of CSC with G. oppositifolia leaves, as a supplement to a basal diet of sorghum hay. Body weight (BW) gain and wool yield responses to the supplements were examined with 36 lambs (27 ± 3 kg BW; age 11 ± 1 months) for 15 weeks. The lambs were only grazed on local pasture (control group) or supplemented with CSC, G. oppositifolia leaves, and their mixture on iso-N basis. Addition of the supplements increased (P < 0.05) BW gain and wool yield, and the leaves were as effective as CSC. These results demonstrated that G. oppositifolia leaves provide good quality green fodder during the prolonged winter feed scarcity period, and that the leaves can be efficiently utilized as a CP supplement to the low-quality diets of sheep.

  15. Soil CO2 emission as related to incorporation of sugarcane crop residues and aggregate breaking after rotary tiller Emissão de CO2 do solo em função da incorporação de palha de cana-de-açúcar e quebra de agregados após preparo com enxada rotativa

    Directory of Open Access Journals (Sweden)

    Luis G Teixeira

    2011-12-01

    Full Text Available Soil tillage is a process that accelerates soil organic matter decomposition transferring carbon to atmosphere, mainly in the CO2 form. In this study, the effect of rotary tillage on soil CO2 emission was investigated, including the presence of crop residues on the surface.Emissions were evaluated during 15 days after tillage in 3 plots: 1 non-tilled and without crop residues on soil surface (NTwo, 2 rotary tiller without the presence of crop residues on soil surface (RTwo, and 3 rotary tiller with the presence of crop residues in soil surface (RTw. Emissions from the RTw plot were higher than the other plots, (0.777 g CO2 m-2 h-1, with the lowest emissions recorded in the NTwo plot (0.414 g CO2 m-2 h-1. Total emission indicates that the difference of C-CO2 emitted to atmosphere corresponds to 3% of the total additional carbon in the crop residues in the RTw plot compared to RTwo. The increase in the RTwo emission in comparison to NTwo was followed by changes in the aggregate size distribution, especially those with average diameter lower than 2 mm. The increase in emission from the RTw plot in relation to RTwo was related to a decrease in crop residue mass on the surface, and its higher fragmentation and incorporation in soil. When the linear correlation between soil CO2 emission, and soil temperature and soil moisture is considered, only the RTw treatment showed significant correlation (pO preparo do solo é um dos processos que aceleram a decomposição da matéria orgânica, transferindo carbono para atmosfera, principalmente na forma de CO2. Neste trabalho, investigou-se o efeito do preparo com enxada rotativa sobre as emissões de CO2 do solo durante 02 semanas após o preparo do solo, incluindo-se a presença de resíduos vegetais sobre a superfície. As emissões foram avaliadas por 15 dias após preparo em 3 parcelas: 1 sem preparo e sem palha superficial (SPs; 2 preparo com enxada rotativa sem a presença de palha na superfície (ERs

  16. Resource capture by single leaves

    Energy Technology Data Exchange (ETDEWEB)

    Long, S.P.

    1992-05-01

    Leaves show a variety of strategies for maximizing CO{sub 2} and light capture. These are more meaningfully explained if they are considered in the context of maximizing capture relative to the utilization of water, nutrients and carbohydrates reserves. There is considerable variation between crops in their efficiency of CO{sub 2} and light capture at the leaf level. Understanding of these mechanisms indicate some ways in which efficiency of resource capture could be level cannot be meaningfully considered without simultaneous understanding of implications at the canopy level. 36 refs., 5 figs., 1 tab.

  17. Growth and Productivity of Response of Hybrid Rice to Application of Animal Manures, Plant Residues and Phosphorus

    Directory of Open Access Journals (Sweden)

    Dr. Amanullah

    2016-10-01

    Full Text Available The objective of this research was to evaluate the impact of organic sources (animal manures vs. plant residues at the rate of 10 t ha-1 each on the productivity profitability of small land rice (Oryza sativa L. grower under different levels of phosphorus (0, 30, 60 and 90 kg P ha-1 fertilization. Two separate field experiments were conducted. In experiment (1, impact of three animal manures sources (cattle, sheep & poultry manures and P levels was studied along with one control plot (no animal manure and P applied as check was investigated. In experiment (2, three plant residues sources (peach leaves, garlic residues & wheat straw and P levels was studied along with one control plot (no plant residues and P applied as check. Both the experiments were carried out on small land farmer field at District Swabi, Khyber Pakhtunkhwa Province (Northwest Pakistan during summer 2015. The results revealed that in both experiments the control plot had significantly (p≤0.05 less productivity than the average of all treated plots with organic sources and P level. The increase in P levels in both experiments (animal manure vs. plant residues had resulted in higher rice productivity (90 = 60 > 30 > 0 kg P ha-1. In the experiment under animal manures, application of poultry manure increased rice productivity as compared with sheep and cattle manures (poultry > sheep > cattle manures. In the experiment under plant residues, application of peach leaves or garlic resides had higher rice productivity over wheat straw (peach leaves = garlic residues > wheat straw. On the average, the rice grown under animal manures produced about 20% higher grain yield than the rice grown under crop residues. We concluded from this study that application of 90 kg P ha-1 along with combined application of animal manures especially poultry manure could increase rice productivity. We conclude from this study that application of 90 kg P ha-1 along with combined application of animal

  18. Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE: emissions of particulate matter from wood- and dung-fueled cooking fires, garbage and crop residue burning, brick kilns, and other sources

    Directory of Open Access Journals (Sweden)

    T. Jayarathne

    2018-02-01

    Full Text Available The Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE characterized widespread and under-sampled combustion sources common to South Asia, including brick kilns, garbage burning, diesel and gasoline generators, diesel groundwater pumps, idling motorcycles, traditional and modern cooking stoves and fires, crop residue burning, and heating fire. Fuel-based emission factors (EFs; with units of pollutant mass emitted per kilogram of fuel combusted were determined for fine particulate matter (PM2.5, organic carbon (OC, elemental carbon (EC, inorganic ions, trace metals, and organic species. For the forced-draft zigzag brick kiln, EFPM2.5 ranged from 12 to 19 g kg−1 with major contributions from OC (7 %, sulfate expected to be in the form of sulfuric acid (31.9 %, and other chemicals not measured (e.g., particle-bound water. For the clamp kiln, EFPM2.5 ranged from 8 to 13 g kg−1, with major contributions from OC (63.2 %, sulfate (23.4 %, and ammonium (16 %. Our brick kiln EFPM2.5 values may exceed those previously reported, partly because we sampled emissions at ambient temperature after emission from the stack or kiln allowing some particle-phase OC and sulfate to form from gaseous precursors. The combustion of mixed household garbage under dry conditions had an EFPM2.5 of 7.4 ± 1.2 g kg−1, whereas damp conditions generated the highest EFPM2.5 of all combustion sources in this study, reaching up to 125 ± 23 g kg−1. Garbage burning emissions contained triphenylbenzene and relatively high concentrations of heavy metals (Cu, Pb, Sb, making these useful markers of this source. A variety of cooking stoves and fires fueled with dung, hardwood, twigs, and/or other biofuels were studied. The use of dung for cooking and heating produced higher EFPM2.5 than other biofuel sources and consistently emitted more PM2.5 and OC than burning hardwood and/or twigs; this trend was consistent across traditional mud

  19. Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE): emissions of particulate matter from wood- and dung-fueled cooking fires, garbage and crop residue burning, brick kilns, and other sources

    Science.gov (United States)

    Jayarathne, Thilina; Stockwell, Chelsea E.; Bhave, Prakash V.; Praveen, Puppala S.; Rathnayake, Chathurika M.; Robiul Islam, Md.; Panday, Arnico K.; Adhikari, Sagar; Maharjan, Rashmi; Goetz, J. Douglas; DeCarlo, Peter F.; Saikawa, Eri; Yokelson, Robert J.; Stone, Elizabeth A.

    2018-02-01

    The Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE) characterized widespread and under-sampled combustion sources common to South Asia, including brick kilns, garbage burning, diesel and gasoline generators, diesel groundwater pumps, idling motorcycles, traditional and modern cooking stoves and fires, crop residue burning, and heating fire. Fuel-based emission factors (EFs; with units of pollutant mass emitted per kilogram of fuel combusted) were determined for fine particulate matter (PM2.5), organic carbon (OC), elemental carbon (EC), inorganic ions, trace metals, and organic species. For the forced-draft zigzag brick kiln, EFPM2.5 ranged from 12 to 19 g kg-1 with major contributions from OC (7 %), sulfate expected to be in the form of sulfuric acid (31.9 %), and other chemicals not measured (e.g., particle-bound water). For the clamp kiln, EFPM2.5 ranged from 8 to 13 g kg-1, with major contributions from OC (63.2 %), sulfate (23.4 %), and ammonium (16 %). Our brick kiln EFPM2.5 values may exceed those previously reported, partly because we sampled emissions at ambient temperature after emission from the stack or kiln allowing some particle-phase OC and sulfate to form from gaseous precursors. The combustion of mixed household garbage under dry conditions had an EFPM2.5 of 7.4 ± 1.2 g kg-1, whereas damp conditions generated the highest EFPM2.5 of all combustion sources in this study, reaching up to 125 ± 23 g kg-1. Garbage burning emissions contained triphenylbenzene and relatively high concentrations of heavy metals (Cu, Pb, Sb), making these useful markers of this source. A variety of cooking stoves and fires fueled with dung, hardwood, twigs, and/or other biofuels were studied. The use of dung for cooking and heating produced higher EFPM2.5 than other biofuel sources and consistently emitted more PM2.5 and OC than burning hardwood and/or twigs; this trend was consistent across traditional mud stoves, chimney stoves, and three-stone cooking

  20. Desempenho de forrageiras em sistemas alagados de tratamento de águas residuárias do processamento do café Performance of forage crops in wetlands used in the treatment of wastewater of coffee processing

    Directory of Open Access Journals (Sweden)

    Ronaldo Fia

    2010-01-01

    Full Text Available Duas gramíneas forrageiras de inverno, azevém (Lolium multiflorum e aveia preta (Avena strigosa Schreb, foram cultivadas em sistemas alagados construídos (SACs utilizados no tratamento das águas residuárias do processamento dos frutos do cafeeiro (ARC com o objetivo de se avaliar seu desempenho agronômico. Essas forrageiras foram submetidas a diferentes cargas orgânicas (650 a 1.500 kg ha-1 d-1 de DQO, proporcionadas pela aplicação dos efluentes de filtros anaeróbios, utilizados no tratamento da ARC. Como tratamento testemunha, as mesmas espécies vegetais foram cultivadas em solução de Hoagland. A matéria seca produzida pelas forrageiras ao longo dos 53 dias de monitoramento dos SACs variou de 7,4 a 14,0 e 0,5 a 2,7 t ha-1, e os rendimentos acumulados de proteína bruta variaram de 1.017 a 2.187 e 66,6 a 316,8 kg ha-1 para o azevém e a aveia, respectivamente. Os resultados permitiram concluir que, dentre as forrageiras estudadas, o azevém se mostrou mais adequado para ser cultivado em SACs utilizados no pós-tratamento da ARC efluente de filtros anaeróbios, já que apresentou maior rendimento de matéria seca e proteína bruta e, portanto, melhor adaptação ao sistema.Two winter grasses, ryegrass (Lolium multiflorum and oats (Avena strigosa Schreb, were grown in constructed wetlands (SACs used in the treatment of wastewater of coffee processing (ARC with the aim to evaluate their agronomic performance. These forage crops were submitted to different organic loads (650 to 1500 kg ha-1 d-1 of COD, offered by the application of anaerobic effluent filters, used in the treatment of ARC. As a control treatment, the same plant species were grown in a Hoagland solution. The forage dry matter produced by over 53 days of monitoring SACs ranged from 7.4 to 14.0 and from 0.5 to 2.7 t ha-1, and the crude protein yield ranged from 1017 to 2187 and 66.6 to 316.8 kg ha-1 for ryegrass and oats, respectively. The results showed that, among the

  1. Eficiência de uso da água e produção de repolho sobre diferentes quantidades de palhada em plantio direto Water use efficiency and cabbage production under no-tillage using different rates of crop residues

    Directory of Open Access Journals (Sweden)

    Waldir Aparecido Marouelli

    2010-04-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito do sistema de plantio direto (PD sobre diferentes quantidades de palhada, na eficiência de uso da água e na produção de repolho. Foram utilizadas quatro quantidades de palhada de milho sobre um Latossolo Vermelho de textura argilosa (0,0, 4,5, 9,0, 13,5 Mg ha-1 de matéria seca, com o sistema de plantio convencional (PC como controle. O delineamento experimental utilizado foi o de blocos ao acaso com três repetições. O estande de plantas, a produtividade, a massa de matéria fresca, o diâmetro, a altura e a compacidade de cabeças de repolho não foram afetados significativamente pelos tratamentos. Houve uma redução de até 13% na lâmina líquida de água aplicada durante o ciclo do repolho cultivado em sistema de PD com palhada, quando comparada à utilizada em tratamentos sem palhada. Durante os primeiros 30 dias após o transplante de mudas, a economia de água chegou a 28%. O índice de produtividade da água em sistema de PD apresentou incremento linear com o aumento da quantidade de palhada utilizada, e foi até 21% maior que no sistema de PC.The objective of this work was to assess the effect of no-tillage production system (PD using different rates of crop residues on cabbage water use efficiency and yield. Four rates of corn crop residues (0.0, 4.5, 9.0, 13.5 Mg ha-1 of dry matter were tested in a clayed Latossolo Vermelho (Rhodic Haplustox, using the conventional tillage system (PC as control. A completely randomized block design, with three replications was used. Cabbage stand, yield, fresh matter mass, diameter, height, and head compactness were not significantly affected by treatments. The total water depth applied along the entire crop cycle in PD treatments was up to 13% smaller than the treatments without residues. Water savings during the 30 days following transplanting reached 28%. The water productivity index increased linearly with crop residue rates under PD

  2. Influence of crop management practices on bean foliage arthropods.

    Science.gov (United States)

    Pereira, J L; Picanço, M C; Pereira, E J G; Silva, A A; Jakelaitis, A; Pereira, R R; Xavier, V M

    2010-12-01

    Crop management practices can affect the population of phytophagous pest species and beneficial arthropods with consequences for integrated pest management. In this study, we determined the effect of no-tillage and crop residue management on the arthropod community associated with the canopy of common beans (Phaseolus vulgaris L.). Abundance and species composition of herbivorous, detritivorous, predaceous and parasitoid arthropods were recorded during the growing seasons of 2003 and 2004 in Coimbra County, Minas Gerais State, Brazil. Arthropod diversity and guild composition were similar among crop management systems, but their abundance was higher under no-tillage relative to conventional cultivation and where residues from the preceding crop were maintained in the field. Thirty-four arthropod species were recorded, and those most representative of the impact of the crop management practices were Hypogastrura springtails, Empoasca kraemeri and Circulifer leafhoppers, and Solenopsis ants. The infestation levels of major insect-pests, especially leafhoppers (Hemiptera: Cicadellidae), was on average seven-fold lower under no-tillage with retention of crop residues relative to the conventional system with removal of residues, whereas the abundance of predatory ants (Hymenoptera: Formicidae) and springtails (Collembola: Hypogastruridae) were, respectively, about seven- and 15-fold higher in that treatment. Importantly, a significant trophic interaction among crop residues, detritivores, predators and herbivores was observed. Plots managed with no-tillage and retention of crop residues had the highest bean yield, while those with conventional cultivation and removal of the crop residues yielded significantly less beans. This research shows that cropping systems that include zero tillage and crop residue retention can reduce infestation by foliar insect-pests and increase abundance of predators and detritivores, thus having direct consequences for insect pest management.

  3. Using cereal rye (catch crop) and dehydrogenase activity as indicators of the residual fertility effects of anaerobic soil disinfestation and other biological soil management practices following field tomato production

    Science.gov (United States)

    Anaerobic soil disinfestation (ASD) and other biological soil management practices employing carbon-rich and/or biologically-active ingredients help contribute to overall soil suppressiveness in crop disease management. However, their roles in soil fertility tended to be overshadowed by disease cont...

  4. Parental Leave in Denmark

    DEFF Research Database (Denmark)

    Rostgaard, Tine; Christoffersen, Mogens; Weise, Hanne

    This artcle considders the political aims for different leave schemes and reviews studies af these schemes. The use of parental leave is sensitive to the financial loss involved in taking leave: a decrease in the benefit payments has had a significant influence on take-up, while, in general, fami......, families'' loss of income is less if leave is taken up by the mothers. Only few fathers participate in parental leave....

  5. Parameterization models for pesticide exposure via crop consumption.

    Science.gov (United States)

    Fantke, Peter; Wieland, Peter; Juraske, Ronnie; Shaddick, Gavin; Itoiz, Eva Sevigné; Friedrich, Rainer; Jolliet, Olivier

    2012-12-04

    An approach for estimating human exposure to pesticides via consumption of six important food crops is presented that can be used to extend multimedia models applied in health risk and life cycle impact assessment. We first assessed the variation of model output (pesticide residues per kg applied) as a function of model input variables (substance, crop, and environmental properties) including their possible correlations using matrix algebra. We identified five key parameters responsible for between 80% and 93% of the variation in pesticide residues, namely time between substance application and crop harvest, degradation half-lives in crops and on crop surfaces, overall residence times in soil, and substance molecular weight. Partition coefficients also play an important role for fruit trees and tomato (Kow), potato (Koc), and lettuce (Kaw, Kow). Focusing on these parameters, we develop crop-specific models by parametrizing a complex fate and exposure assessment framework. The parametric models thereby reflect the framework's physical and chemical mechanisms and predict pesticide residues in harvest using linear combinations of crop, crop surface, and soil compartments. Parametric model results correspond well with results from the complex framework for 1540 substance-crop combinations with total deviations between a factor 4 (potato) and a factor 66 (lettuce). Predicted residues also correspond well with experimental data previously used to evaluate the complex framework. Pesticide mass in harvest can finally be combined with reduction factors accounting for food processing to estimate human exposure from crop consumption. All parametric models can be easily implemented into existing assessment frameworks.

  6. Cover crops effect on farm benefits and nitrate leaching: linking economic and environmental analysis

    Science.gov (United States)

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

    2013-04-01

    Introducing cover crops interspersed with intensively fertilized crops in rotation has the potential to reduce nitrate leaching. However, despite the evident environmental services provided and the range of agronomic benefits documented in the literature, farmers' adoption of the technique is still limited because growing CC could lead to extra costs for the farm in three different forms: direct, indirect, and opportunity costs. Environmental studies are complex, and evaluating the indicators that are representative of the environmental impact of an agricultural system is a complicated task that is conducted by specialized groups and methodologies. Multidisciplinary studies may help to develop reliable approaches that would contribute to choosing the best agricultural strategies based on linking economic and environmental benefits. This study evaluates barley (Hordeum vulgare L., cv. Vanessa), vetch (Vicia villosa L., cv. Vereda) and rapeseed (Brassica napus L., cv. Licapo) as cover crops between maize, leaving the residue in the ground or selling it for animal feeding, and compares the economic and environmental results with respect to a typical maize-fallow rotation. Nitrate leaching for different weather conditions was calculated using the mechanistic-deterministic WAVE model, using the Richards equation parameterised with a conceptual model for the soil hydraulic properties for describing the water flow in the vadose zone, combined with field observed data. The economic impact was evaluated through stochastic (Monte-Carlo) simulation models of farms' profits using probability distribution functions of maize yield and cover crop biomass developed fitted with data collected from various field trials (during more than 5 years) and probability distribution functions of maize and different cover crop forage prices fitted from statistical sources. Stochastic dominance relationships are obtained to rank the most profitable strategies from a farm financial perspective

  7. Resíduos da agroindústria de chá preto como substrato para produção de mudas de hortaliças Agroindustry residues of the black tea as substrate for growing seedlings of vegetable crops

    Directory of Open Access Journals (Sweden)

    Juliana Domingues Lima

    2007-12-01

    %. In the growth assays, seeds were placed in trays containing: 1. vermiculite; 2. decomposed residue plus vermiculite; 3. decomposed residue and 4. crude residue washed plus vermiculite. The decomposed residue was obtained from crude residue decomposition process and the crude residue washed from crude residue washing in water. For the assays were adopted the randomized completely experimental design with four treatments and four repetitions of thirty seeds each. The results indicated that aqueous extract inhibited the seeds germination and seedlings growth of lettuce, tomato and cucumber. The crude residue washed plus vermiculite also reduced the seedlings emergency. On the other hand, the decomposed residue and decomposed residue plus vermiculite stimulated the seedlings emergency and growth. The decomposition process possibilited the use of black tea industry residue as substrate for seedlings growing of vegetable crops.

  8. Crop Sequence Influences on Sustainable Spring Wheat Production in the Northern Great Plains

    Directory of Open Access Journals (Sweden)

    Joseph M. Krupinsky

    2010-11-01

    Full Text Available Cropping systems in American agriculture are highly successful since World War II, but have become highly specialized, standardized, and simplified to meet the demands of an industrialized food system. Minimal attention has been given to the efficient exploitation of crop diversity and the synergistic and/or antagonistic relationships of crops in crop sequences. Objectives of our research were to determine if previous crop sequences have long-term benefits and/or drawbacks on spring wheat seed yield, seed N concentration, and seed precipitation-use efficiency in the semiarid northern Great Plains, USA. Research was conducted 6 km southwest of Mandan, ND using a 10 × 10 crop matrix technique as a research tool to evaluate multiple crop sequence effects on spring wheat (triticum aestivum L. production in 2004 and 2005. Spring wheat production risks can be mitigated when second year crop residue was dry pea (Pisium sativum L. averaged over all first year crop residues. When compared to spring wheat as second year crop residue in the dry year of 2004, dry pea as the second year residue crop resulted in a 30% spring wheat seed yield increase. Sustainable cropping systems need to use precipitation efficiently for crop production, especially during below average precipitation years like 2004. Precipitation use efficiency average over all treatments, during the below average precipitation year was 23% greater than the above average precipitation year of 2005. Diversifying crops in cropping systems improves production efficiencies and resilience of agricultural systems.

  9. FORAGES AND PASTURES SYMPOSIUM: Optimizing the use of fibrous residues in beef and dairy diets.

    Science.gov (United States)

    Watson, A K; MacDonald, J C; Erickson, G E; Kononoff, P J; Klopfenstein, T J

    2015-06-01

    Increased corn prices over the past decade have altered land use away from traditional forage in favor of corn. Accordingly, beef and dairy producers have had to adopt nontraditional forage resources into their production systems, many of which have become available as a result of increased corn production. Corn residues have become more available due to increases in corn hectares and yield. The individual plant components (i.e., husk, leaf, and stem) vary in fiber digestibility (NDF digestibility estimates = 40.5, 31.4, and 0.6% ± 0.8 for husk, leaf, and stalk, respectively). Stocking cattle to consume 3.6 kg forage/25.5 kg of grain allows cattle to graze selectively; selection of husks and leaves improves cattle performance. Byproducts of the wet and dry milling industries can be supplemented to calves grazing corn residues to provide protein and energy. Optimal gains were observed when these byproducts were supplemented at approximately 2.5 kg/d to 250-kg growing calves. Gestating beef cows do not require supplemental inputs when grazing corn residue, if stocked appropriately. Alkaline treatment of crop residues improves their feeding value. Concentrations of up to 20% harvested corn residue treated with calcium oxide can be included in finishing diets with an average of 1.3% reduction in G:F when diets contain 40% wet or modified distillers grains. Conversely, when untreated corn residues are included in similar finishing diets, G:F is reduced by 13.4%. Calcium oxide-treated residues included in beef growing diets increases DMI and ADG without significant improvements in G:F. Calcium oxide treatment of corn residues has been evaluated in dairy diets by replacing corn or corn silage with variable results. Efficient use of nontraditional fiber sources, such as corn milling byproducts and corn residue, are critical to the future viability of ruminant animal production.

  10. Residual stresses

    International Nuclear Information System (INIS)

    Sahotra, I.M.

    2006-01-01

    The principal effect of unloading a material strained into the plastic range is to create a permanent set (plastic deformation), which if restricted somehow, gives rise to a system of self-balancing within the same member or reaction balanced by other members of the structure., known as residual stresses. These stresses stay there as locked-in stresses, in the body or a part of it in the absence of any external loading. Residual stresses are induced during hot-rolling and welding differential cooling, cold-forming and extruding: cold straightening and spot heating, fabrication and forced fitting of components constraining the structure to a particular geometry. The areas which cool more quickly develop residual compressive stresses, while the slower cooling areas develop residual tensile stresses, and a self-balancing or reaction balanced system of residual stresses is formed. The phenomenon of residual stresses is the most challenging in its application in surface modification techniques determining endurance mechanism against fracture and fatigue failures. This paper discusses the mechanism of residual stresses, that how the residual stresses are fanned and what their behavior is under the action of external forces. Such as in the case of a circular bar under limit torque, rectangular beam under limt moment, reclaiming of shafts welds and peening etc. (author)

  11. Nutritional potential of post extraction residues and silage from ...

    African Journals Online (AJOL)

    Nutritional potential of post extraction residues and silage from leaves of five cassava varieties as feed for ruminants. ... Results indicated that processing reduced (P < 0.05) the inherent nutrients of cassava leaf residues produced after the extraction of protein concentrate from cassava leaves with crude protein (CP) content ...

  12. Goodbye, Mandatory Maternity Leaves

    Science.gov (United States)

    Nation's Schools, 1972

    1972-01-01

    In precedent-setting decrees, courts and federal and State authorities have branded compulsory maternity leaves either unconstitutional or illegal. School administrators are urged to prod boards of education to adopt more lenient maternity leave policies -- now. (Author)

  13. Leaving home in Denmark

    DEFF Research Database (Denmark)

    Nielsen, Rikke Skovgaard

    2015-01-01

    The paper focuses on ethnic differences in the timing and patterns of leaving the parental home. Leaving home is a key transition in the life course of the individual, and extensive research has been conducted on the timing and patterns of leaving it. However, ethnic differences in these patterns...... of leaving home. Results showed that while some differences disappeared when controlling for covariates, others persisted, thus indicating ethnic differences in home-leaving patterns. A strong link between leaving home and marriage was substantiated for Turks, but not for Somalis. The home-leaving patterns...... of Somalis were much more similar to those of Danes. Overall, Turkish descendants were similar to Turkish immigrants but with some differentiation. The analyses identified the existence of ethnic differences in home-leaving patterns but also found evidence of a shift towards less traditional patterns, i...

  14. Mobilidade de íons em solo ácido com aplicação de calcário, ácido orgânico e material vegetal em superfície Ion mobility in acid soils with surface application of lime, organic acid and crop residues

    Directory of Open Access Journals (Sweden)

    Milton Ferreira Moraes

    2007-08-01

    Full Text Available Há controvérsias quanto à eficiência da correção da acidez da camada subsuperficial pela aplicação de calcário na presença de materiais vegetais de plantas de cobertura e faltam informações sobre os mecanismos envolvidos no processo. O objetivo deste estudo foi quantificar a contribuição dos materiais vegetais de plantas de cobertura, com ênfase nos seus conteúdos de ácidos orgânicos de baixa massa molar e nutrientes solúveis, sobre a mobilização, no perfil do solo, dos produtos da dissolução do calcário aplicado em superfície. Foram desenvolvidos dois experimentos em laboratório, usando colunas de PVC de 30 cm de altura com amostras deformadas de um Latossolo Vermelho textura muito argilosa. Os tratamentos constituíram-se da aplicação isolada ou conjunta de calcário para atingir 80 % de saturação por bases (6,1 t ha-1 e de materiais vegetais (20 t ha-1 de nabo forrageiro e aveia-preta, bem como de soluções de ácidos orgânicos e sais neutros aproximadamente equivalentes ao conteúdo dessas espécies. A calagem isolada ou em associação com os materiais vegetais promoveu a redução da acidez somente na camada superficial (0-8 cm. A baixa taxa de recuperação dos ácidos orgânicos adicionados (The efficiency of subsurface acidity alleviation by surface liming in the presence of crop residues is controversial and more information is needed. The objective of this study was to quantify the contribution of cover crop residues, regarding their contents of low molar mass organic acids and soluble nutrients to mobilization in the soil profile of the reaction products of surface-applied lime. Two experiments were carried out under laboratory conditions using 30 cm high PVC cylinders filled with acid and clayey Red Latosol. Treatments consisted of liming to 80 % soil base saturation (6.1 t ha-1 solely as or liming combined with radish (Raphanus sativus or with black oat (Avena strigosa crop residues (20 t ha-1, as

  15. Soil thresholds and a decision tool to manage food safety of crops grown in chlordecone polluted soil in the French West Indies.

    Science.gov (United States)

    Clostre, Florence; Letourmy, Philippe; Lesueur-Jannoyer, Magalie

    2017-04-01

    Due to the persistent pollution of soils by an organochlorine, chlordecone (CLD also known as Kepone © ) in the French West Indies, some crops may be contaminated beyond the European regulatory threshold, the maximum residue limit (MRL). Farmers need to be able to foresee the risk of not complying with the regulatory threshold in each field and for each crop, if not, farmers whose fields are contaminated would have to stop cultivating certain crops in the fields concerned. To help farmers make the right choices, we studied the relationship between contamination of the soil and contamination of crops. We showed that contamination of a crop by CLD depended on the crop concerned, the soil CLD content and the type of soil. We grouped crop products in three categories: (i) non-uptakers and low-uptakers, (ii) medium-uptakers, and (iii) high-uptakers, according to their level of contamination and the resulting risk of exceeding MRL. Using a simulation model, we computed the soil threshold required to ensure the risk of not complying with MRL was sufficiently low for each crop product and soil type. Threshold values ranged from 0.02 μgkg -1 for dasheen grown in nitisol to 1.7 μgkg -1 for yam grown in andosol in the high-uptake category, and from 1 μgkg -1 for lettuce grown in nitisol to 45 μgkg -1 for the leaves of spring onions grown in andosol in the medium-uptake category. Contamination of non-uptakers and low-uptakers did not depend on soil contamination. With these results, we built an easy-to-use decision support tool based on two soil thresholds (0.1 and 1 μgkg -1 ) to enable growers to adapt their cropping system and hence to be able to continue farming. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Residual stresses

    International Nuclear Information System (INIS)

    Macherauch, E.

    1978-01-01

    Residual stresses are stresses which exist in a material without the influence of external powers and moments. They come into existence when the volume of a material constantly changes its form as a consequence of mechanical, thermal, and/or chemical processes and is hindered by neighbouring volumes. Bodies with residual stress are in mechanical balance. These residual stresses can be manifested by means of all mechanical interventions disturbing this balance. Acoustical, optical, radiological, and magnetical methods involving material changes caused by residual stress can also serve for determining residual stress. Residual stresses have an ambivalent character. In technical practice, they are feared and liked at the same time. They cause trouble because they can be the cause for unexpected behaviour of construction elements. They are feared since they can cause failure, in the worst case with catastrophical consequences. They are appreciated, on the other hand, because, in many cases, they can contribute to improvements of the material behaviour under certain circumstances. But they are especially liked for their giving convenient and (this is most important) mostly uncontrollable explanations. For only in very few cases we have enough knowledge and possibilities for the objective evaluation of residual stresses. (orig.) [de

  17. Emamectin benzoate (Affirm). a modern insecticide for the control of lepidoptera larvae on fruits, grapes and vegetables crops.

    Science.gov (United States)

    Liguori, R; Correia, R; Thomas, C; Decaudin, B; Cisneros, J; Lopez, A

    2010-01-01

    Emamectin benzoate (Affirm) is a novel insecticide with potent efficacy against many specie of lepidoptera which are damaging fruits and leaves of agricultural crops. The active ingredient belongs to the naturally derived chemical group of avermectine, causing paralysis of lepidoptera larvae due to the activation of chloride channel at nerves level. Affirm is acting mainly through ingestion, due to its mode of action and fast activity, it is effective at very low rates and on all instars stages. It has been developed for the use on pomefruits, stonefruits, grapes and a broda range of vegetables crops at a rate range of 1.5 to 3 g ai/100L. The product shows translaminar activity and rapid degradation on leaf surface; therefore the active ingredient breaks down in a very short time to sublethal doses for most beneficials organisms living on the vegetation. The short rentry time, generally 24 hours for beneficials and impollinators, makes Affirm compatible for IPM programme in orchards and greenhouses. Also the residue profile is very favourable, leading to a very low maximum residue level and short preharvest interval in all edible crops.

  18. Watershed Scale Optimization to Meet Sustainable Cellulosic Energy Crop Demand

    Energy Technology Data Exchange (ETDEWEB)

    Chaubey, Indrajeet [Purdue Univ., West Lafayette, IN (United States); Cibin, Raj [Purdue Univ., West Lafayette, IN (United States); Bowling, Laura [Purdue Univ., West Lafayette, IN (United States); Brouder, Sylvie [Purdue Univ., West Lafayette, IN (United States); Cherkauer, Keith [Purdue Univ., West Lafayette, IN (United States); Engel, Bernard [Purdue Univ., West Lafayette, IN (United States); Frankenberger, Jane [Purdue Univ., West Lafayette, IN (United States); Goforth, Reuben [Purdue Univ., West Lafayette, IN (United States); Gramig, Benjamin [Purdue Univ., West Lafayette, IN (United States); Volenec, Jeffrey [Purdue Univ., West Lafayette, IN (United States)

    2017-03-24

    The overall goal of this project was to conduct a watershed-scale sustainability assessment of multiple species of energy crops and removal of crop residues within two watersheds (Wildcat Creek, and St. Joseph River) representative of conditions in the Upper Midwest. The sustainability assessment included bioenergy feedstock production impacts on environmental quality, economic costs of production, and ecosystem services.

  19. Negative leave balances

    CERN Multimedia

    Human Resources Department

    2005-01-01

    Members of the personnel entitled to annual leave and, where appropriate, saved leave and/or compensatory leave are requested to take note of the new arrangements described below, which were recommended by the Standing Concertation Committee (SCC) at its meeting on 1Â September 2005 and subsequently approved by the Director-General. The changes do not apply to members of the personnel participating in the Progressive Retirement Programme (PRP) or the Part-time Work as a pre-retirement measure, for whom the specific provisions communicated at the time of joining will continue to apply. Â Negative balances in annual leave, saved leave and/or compensatory leave accounts at the end of the leave year (30th September) and on the date on which bonuses are credited to the saved leave account (31st December): Where members of the personnel have a leave account with a negative balance on 30Â September and/or 31Â December, leave will automatically be transferred from one account to another on the relevant dates i...

  20. Negative leave balances

    CERN Multimedia

    Human Resources Department

    2005-01-01

    Members of the personnel entitled to annual leave and, where appropriate, saved leave and/or compensatory leave are requested to take note of the new arrangements described below, which were recommended by the Standing Concertation Committee (SCC) at its meeting on 1 September 2005 and subsequently approved by the Director-General. The changes do not apply to members of the personnel participating in the Progressive Retirement Programme (PRP) or the Part-time Work as a pre-retirement measure, for whom the specific provisions communicated at the time of joining will continue to apply.  Negative balances in annual leave, saved leave and/or compensatory leave accounts at the end of the leave year (30th September) and on the date on which bonuses are credited to the saved leave account (31st December): Where members of the personnel have a leave account with a negative balance on 30 September and/or 31 December, leave will automatically be transferred from one account to another on the relevant dates in or...

  1. Decomposição e liberação de nutrientes de resíduos culturais de plantas de cobertura em argissolo vermelho-amarelo na região noroeste Fluminense (RJ Decomposition and nutrient release from cover crop residues in passion-fruit plantation

    Directory of Open Access Journals (Sweden)

    Antonio Carlos da Gama-Rodrigues

    2007-12-01

    release from cover crop residues in a passion-fruit plantation. The evaluated species were Canavalia ensiformis, Arachis pintoi, Macroptilium atropurpureum, Pueraria phaseoloides and Brachiaria brizantha. Litter decomposition was measured using nylon, 2.0 mm mesh, litter bags during 140 days. The single exponential model adjusted best for all cover crop species. Litter decay rates of Canavalia ensiformis and Arachis pintoi were significantly higher than in those of other species. The C, N, P, Ca and Mg release rates from Canavalia ensiformis residue were the highest. However, K release rate was the highest for Arachis pintoi. For all residues the K and polyphenol release rates were higher than those of the other elements. C, N, P, Ca and Mg release rates were positively correlated with litter decay rate. The litter decay rate, C, nutrients, and polyphenol release rates were regulated by litter quality. The different litter decay rates and estimated nutrient release rates indicate the potential of the use of crop residues as nutrient source of passion-fruit.

  2. The Temporary Leave Dilemma -

    DEFF Research Database (Denmark)

    Amilon, Anna

    2010-01-01

    Lone mothers have to take care of a sick child with little or no help from the child’s other parent and have to carry all costs connected to leave-taking. This paper empirically tests whether lone mothers take more temporary parental leave to care for sick children than partnered mothers...... and whether parental leave is associated with a signaling cost. The results from this study of Swedish mothers show that lone mothers use more temporary parental leave than partnered mothers. Further, within the group of lone mothers, those with higher socioeconomic status take less temporary parental leave...... than those with lower socioeconomic status, whereas no such differences are found within the group of partnered mothers. One possible interpretation is that signaling costs negatively influence the utilization of temporary parental leave for lone mothers....

  3. Crop/weed discrimination using near-infrared reflectance spectroscopy (NIRS)

    Science.gov (United States)

    Zhang, Yun; He, Yong

    2006-09-01

    The traditional uniform herbicide application often results in an over chemical residues on soil, crop plants and agriculture produce, which have imperiled the environment and food security. Near-infrared reflectance spectroscopy (NIRS) offers a promising means for weed detection and site-specific herbicide application. In laboratory, a total of 90 samples (30 for each species) of the detached leaves of two weeds, i.e., threeseeded mercury (Acalypha australis L.) and fourleafed duckweed (Marsilea quadrfolia L.), and one crop soybean (Glycine max) was investigated for NIRS on 325- 1075 nm using a field spectroradiometer. 20 absorbance samples of each species after pretreatment were exported and the lacked Y variables were assigned independent values for partial least squares (PLS) analysis. During the combined principle component analysis (PCA) on 400-1000 nm, the PC1 and PC2 could together explain over 91% of the total variance and detect the three plant species with 98.3% accuracy. The full-cross validation results of PLS, i.e., standard error of prediction (SEP) 0.247, correlation coefficient (r) 0.954 and root mean square error of prediction (RMSEP) 0.245, indicated an optimum model for weed identification. By predicting the remaining 10 samples of each species in the PLS model, the results with deviation presented a 100% crop/weed detection rate. Thus, it could be concluded that PLS was an available alternative of for qualitative weed discrimination on NTRS.

  4. Solid residues

    International Nuclear Information System (INIS)

    Mulder, E.; Duin, P.J. van; Grootenboer, G.J.

    1995-01-01

    A summary is presented of the many investigations that have been done on solid residues of atmospheric fluid bed combustion (AFBC). These residues are bed ash, cyclone ash and bag filter ash. Physical and chemical properties are discussed and then the various uses of residues (in fillers, bricks, gravel, and for recovery of aluminium) are summarised. Toxicological properties of fly ash and stack ash are discussed as are risks of pneumoconiosis for workers handling fly ash, and contamination of water by ashes. On the basis of present information it is concluded that risks to public health from exposure to emissions of coal fly ash from AFBC appear small or negligible as are health risk to workers in the coal fly ash processing industry. 35 refs., 5 figs., 12 tabs

  5. Ecological weed management by cover cropping : effects on weed growth in autumn and weed establishment in spring

    NARCIS (Netherlands)

    Kruidhof, H.M.; Bastiaans, L.; Kropff, M.J.

    2008-01-01

    Cover crops grown in the period between two main crops have potential as an important component of a system-oriented ecological weed management strategy. In late summer and autumn, the cover crop can suppress growth and seed production of weeds, whereas the incorporation of cover crop residues in

  6. Evaluating residues from batai trees (Paraserianthes falcataria) as alternative sources of nitrogen for grain corn (zeas mays l.) in the humid tropics

    International Nuclear Information System (INIS)

    Zaharah, A.R.; Chintu, R.; Ghizan, S.

    2002-01-01

    The use of chemical fertilizers for mitigating N deficiency is unsustainable in many tropical areas because of economic constraints and possible deleterious effects on environmental quality. Although organic inputs such as green manures and litter from legumes have shown some potential for improving soil N status, the synchrony of N release from these residues with crop demand needs to be seriously addressed. The potential of above- and below-ground residues of Batai (Paraserianthes falcataria) to improve soil N availability and uptake by corn in an Ultisol (Bungor series) was evaluated under field and controlled conditions. The effect of residue quality on the kinetics of N release and accumulation in the soil was studied in field and laboratory incubation studies, whilst N uptake by grain corn was quantified using direct and indirect 1 5 N isotope labeling techniques. Treatments consist of fresh leaves, roots and 1:1 mixture of roots and leaves of Batai. Residue quality in terms of lignin + polyphenol-to-N ratio, and N mineralization was in the order roots 3 -N leaching occurred between 30 and 60 days after treatment (DAT). Significant amounts of Ca, Mg and K were also leached beyond 20 cm after 60 days. Both 15 N-labeling methods showed that N recovery in corn was much higher in the root than the leaf treatments. However, integrating Batai residues with an inorganic N source could be a more effective management strategy for improving N use efficiency and mitigating soil acidity. (Author)

  7. Liberação de fósforo e potássio durante a decomposição de resíduos culturais em plantio direto Phosphorus and potassium release during decomposition of crops residues in no-tillage system

    Directory of Open Access Journals (Sweden)

    Sandro José Giacomini

    2003-09-01

    and potassium were determined. It was adjusted the asymptotic model [(Pr and Kr = Ae-kt + (100 - A] to observed values for the remaining P and K (Pr and Kr which was used to estimate the rate (k of P and K release and the proportion of these nutrients of the labile (A and recalcitrant (100 - A pools of crop residues. The rate of K release was 4.5 times greater than was for phosphorus. The amount of remaining P in the initial phase of the decomposition was inversely proportional to the concentration of water soluble P in the residues. In the residues of the oat + vetch mixture the P and K release were slower than the observed for single species. These results indicate a greater potential of synchrony between commercial crops P and K demand and P and K release from residues of oat + vetch mixture as compared to single vetch.

  8. Best management practices: Managing cropping systems for soil protection and bioenergy production

    Science.gov (United States)

    Interest in renewable alternatives to fossil fuels has increased. Crop residue such as corn stover or wheat straw can be used for bioenergy including a substitution for natural gas or coal. Harvesting crop residue needs to be managed to protect the soil and future soil productivity. The amount of bi...

  9. Nitrogen release from differently aged Raphanus sativus L. nitrate catch crops during mineralization at autumn temperatures

    DEFF Research Database (Denmark)

    Thomsen, Ingrid Kaag; Elsgaard, Lars; Olesen, Jørgen Eivind

    2016-01-01

    radish (Raphanus sativus, L.) has emerged as a promising nitrate catch crop in cereal cropping, although the course of remineralization of residue N following termination of this frost-sensitive crucifer remains obscured. We incubated radish residues of different age (different planting and harvest dates...

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

    Directory of Open Access Journals (Sweden)

    Moslem Ladoni

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

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

    Science.gov (United States)

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

    2015-01-01

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

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

    Science.gov (United States)

    Meisner, Matthew H; Rosenheim, Jay A

    2014-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Matthew H Meisner

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

  14. Residual biomass potential of commercial and pre-commercial sugarcane cultivars

    Directory of Open Access Journals (Sweden)

    Marcos Guimarães de Andrade Landell

    2013-10-01

    Full Text Available Sugarcane (Saccharum spp. is an efficient and sustainable alternative for energy generation compared to non-renewable sources. Currently, during the mechanized harvest process, the straw left in the field can be used in part for the second generation ethanol and increasing the electric energy production. Thus, this study aimed to provide information on the potential for residual biomass cultivars of sugarcane cropping system. This study provides the following information: yield of straw, depending on the calculated leaf area index and the number of tillers per linear meter; primary energy production of several sugarcane genotypes; contribution of dry tops and leaves; biomass yield; and evaluation of fiber, cellulose, hemicellulose and lignin. Preliminary results obtained by researchers of the State of São Paulo, Brazil, and reCviews related studies are presented. The results suggest that the production of sugarcane straw content varies according to the cultivars; the greater mass of sugarcane straw is in the top leaves and that the potential for the crude energy production of sugarcane per area unit can be increased using fiber-rich species or species that produce more straw. The straw indexes was shown to be a good indicator and allow the estimation of straw volumes generated in a sugarcane crop. The cellulose, hemicellulose and lignin composition in sugarcane is distinct among varieties. Therefore, it is possible to develop distinct biomass materials for energy production and for the development of sugarcane mills using biochemical processes and thermal routes.

  15. Rainfed intensive crop systems

    DEFF Research Database (Denmark)

    Olesen, Jørgen E

    2014-01-01

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

  16. Residual basins

    International Nuclear Information System (INIS)

    D'Elboux, C.V.; Paiva, I.B.

    1980-01-01

    Exploration for uranium carried out over a major portion of the Rio Grande do Sul Shield has revealed a number of small residual basins developed along glacially eroded channels of pre-Permian age. Mineralization of uranium occurs in two distinct sedimentary units. The lower unit consists of rhythmites overlain by a sequence of black shales, siltstones and coal seams, while the upper one is dominated by sandstones of probable fluvial origin. (Author) [pt

  17. Typology of organic residues attracting flies and their utilization in ...

    African Journals Online (AJOL)

    ADIN

    All rights reserved. Keywords: organic residue, fly larvae, organic manure, soil fertility, farmer perception. ... nutrients in the animal manure, which in turn is fed with crop .... dried fish, rotten meat, human waste, rabbit skin and blood were ...

  18. Parameterization Models for Pesticide Exposure via Crop Consumption

    DEFF Research Database (Denmark)

    Fantke, Peter; Wieland, Peter; Juraske, Ronnie

    2012-01-01

    harvest, degradation half-lives in crops and on crop surfaces, overall residence times in soil, and substance molecular weight. Partition coefficients also play an important role for fruit trees and tomato (Kow), potato (Koc), and lettuce (Kaw, Kow). Focusing on these parameters, we develop crop...... correspond well with results from the complex framework for 1540 substance-crop combinations with total deviations between a factor 4 (potato) and a factor 66 (lettuce). Predicted residues also correspond well with experimental data previously used to evaluate the complex framework. Pesticide mass in harvest...

  19. Residual biomass potential in olive tree cultivation and olive oil industry in Spain: valorization proposal in a biorefinery context

    Directory of Open Access Journals (Sweden)

    Paloma Manzanares

    2017-12-01

    Full Text Available Olive crop and olive oil industry generates several residues, i.e., olive tree pruning biomass (OTPB, extracted olive pomace (EOP and olive leaves (OL that could be used to produce high-added value products in an integrated biorefinery. OTPB is generated in the field as a result of pruning operation to remove old branches; EOP is the main residue of the pomace olive oil extracting industry after extraction with hexane of residual oil contained in olive pomace; and OL comes from the olive cleaning process carried out at olive mills, where small branches and leaves are separated by density. In this work, an analysis of the potential of OTPB, EOP and OL residues was addressed by estimating the production volumes at national level and the spatial distribution of these residues using geographic information system software. Information provided by public institutions and personal surveys to the industries was evaluated. Moreover, chemical analysis of the residues was undertaken and the results used to make a first assessment of valorization into biofuels such as bioethanol and bio based chemicals. Results show that close to 4.2 million tons/year of EOP, OL and OTPB derived from olive oil industry and olive tree cultivation in Spain could be available as a raw material for biorefineries in Spain. The analysis of the chemical characteristics indicates the relevant potential of these feedstocks for the production of bioethanol and other compounds such as phenols based on suitable processing and conversion routes, although techno-economic evaluations must be tackled to refine this approach.

  20. Residual biomass potential in olive tree cultivation and olive oil industry in Spain: valorization proposal in a biorefinery contex

    Energy Technology Data Exchange (ETDEWEB)

    Manzanares, P.; Ruiz, E.; Ballesteros, M.; Negro, M.J.; Gallego, F.J.; López-Linares, J.C.; Castro, E.

    2017-07-01

    Olive crop and olive oil industry generates several residues, i.e., olive tree pruning biomass (OTPB), extracted olive pomace (EOP) and olive leaves (OL) that could be used to produce high-added value products in an integrated biorefinery. OTPB is generated in the field as a result of pruning operation to remove old branches; EOP is the main residue of the pomace olive oil extracting industry after extraction with hexane of residual oil contained in olive pomace; and OL comes from the olive cleaning process carried out at olive mills, where small branches and leaves are separated by density. In this work, an analysis of the potential of OTPB, EOP and OL residues was addressed by estimating the production volumes at national level and the spatial distribution of these residues using geographic information system software. Information provided by public institutions and personal surveys to the industries was evaluated. Moreover, chemical analysis of the residues was undertaken and the results used to make a first assessment of valorization into biofuels such as bioethanol and bio based chemicals. Results show that close to 4.2 million tons/year of EOP, OL and OTPB derived from olive oil industry and olive tree cultivation in Spain could be available as a raw material for biorefineries in Spain. The analysis of the chemical characteristics indicates the relevant potential of these feedstocks for the production of bioethanol and other compounds such as phenols based on suitable processing and conversion routes, although techno-economic evaluations must be tackled to refine this approach.

  1. Lixiviação de potássio da palha de espécies de cobertura de solo de acordo com a quantidade de chuva aplicada Potassium leaching from green cover crop residues as affected by rainfall amount

    Directory of Open Access Journals (Sweden)

    C. A. Rosolem

    2003-04-01

    Full Text Available Os restos vegetais deixados na superfície do solo em sistemas de semeadura direta, além de proteger o solo da erosão, constituem considerável reserva de nutrientes que podem ser disponibilizados para a cultura principal, subseqüente. Avaliou-se a lixiviação de K da palha de seis espécies vegetais com potencial de uso como plantas para cobertura do solo de acordo com a quantidade de chuva recebida após o manejo. Milheto (Pennisetum americanum, var. BN-2, sorgo de guiné (Sorghum vulgare, aveia preta (Avena strigosa, triticale (Triticum secale, crotalária juncea (Crotalaria juncea e braquiária (Brachiaria decumbens foram cultivados em vasos com terra, em casa de vegetação, em Botucatu (SP. Aos 45 dias da emergência, as plantas foram cortadas na altura do colo, secas em estufa e submetidas a chuvas simuladas de 4,4, 8,7, 17,4, 34,9 e 69,8 mm, considerando uma quantidade de palha equivalente a 8,0 t ha-1. A máxima retenção de água pela palha corresponde a uma lâmina de até 3,0 mm, independentemente da espécie, praticamente não ocorrendo lixiviação do potássio com chuvas da ordem de 5 mm. A máxima liberação de K por unidade de chuva ocorre com lâminas de até 20 mm, decrescendo a partir deste ponto. A quantidade de K liberado da palha logo após o manejo depende da espécie vegetal, não ultrapassando, no entanto, 24 kg ha-1 com chuvas da ordem de 70 mm, apresentando correlação positiva com a concentração do nutriente no tecido vegetal. O triticale e a aveia são mais eficientes na ciclagem do potássio.Besides protecting soil from erosion, plant residues left on the soil surface by green cover crops in no-till cropping systems represent a considerable nutrient source of nutrients that can be made available for the following crop. Potassium leaching from the straw of six cover crop species was evaluated, in relation to the amount of rain on the residues. Pearl millet (Pennisetum americanum, guinea sorghum (Sorghum

  2. Crop characteristics and inulin production in chicory

    International Nuclear Information System (INIS)

    Meijer, W.J.M.; Mathijssen, E.W.J.M.

    1992-01-01

    Crop growth, dry matter partitioning, leaf area development, light interception and dry matter : radiation quotient in chicory were studied in field and glasshouse trials. Variations in root and inulin yields were related to sowing time, sowing density and cultivar. Retarded growth of first leaves appeared to be a major factor in limiting productivity. Growth of the first leaves was limited by assimilate supply and by low temperatures. Leaf area expansion exhibited a lag of 350 °Cd from emergence. From that point until crop closure, leaf area index increased exponentially with thermal time. Initially, 60 per cent of the dry matter was partitioned to the leaves; this share gradually decreased to about 10 per cent during later stages. The average dry matter: radiation quotient was 2.6 g MJ -1 for total dry matter and 2.4 g MJ -1 for root dry matter. Cultivars differed in early leaf growth, dry matter partitioning and dry matter: radiation quotient. The crop characteristics are compared with literature data for sugar beet and the prospects for breeding improved genotypes are discussed. (author)

  3. Weed Interference Effects on Leaves, Internode and Harvest Index of Dry Bean (Phaseolus vulgaris L.

    Directory of Open Access Journals (Sweden)

    Hossein GHAMARI

    2015-03-01

    Full Text Available The development of appropriate weed management strategies and efficient use of herbicides relies upon understanding weed-crop interactions. A field study was carried out to assess the effect of weed interference on leaves, internode and harvest index of dry bean (Phaseolus vulgaris L.. The experiment was established under a randomized complete block design with two types of weed interference treatments: plots with weeds and plots without weeds at different time intervals (0, 10, 20, 30, 40 and 50 days after crop emergence. The sigmoid Boltzmann model was used to quantify the crop traits as influenced by weed interference. Prolonged delays in weed removal reduced gradually the number of leaves of the crop. Weed interference decreased dry weight of leaves as well, so that the lowest value of it (33.49 g plant-1 was observed in full season during weed-infested treatment. Infestation of weeds affected the length of the crop internodes. While the weed interference duration increased, the length of the internodes decreased. Harvest index was also sensitive to weed competition. As the crop was kept weed-infested from the emergence for increasing periods of time, harvest index decreased to a value of 28.01%. A significant negative correlation between total biomass of weeds and dry bean traits (number of leaves, leaves dry weight, internode length and harvest index was observed. Therefore, weeds are able to adversely affect dry bean growth through constraining environmental resources and impairing leaves as the photosynthetic areas.

  4. Residual Toxicity of Abamectin, Chlorpyrifos, Cyromazine, Indoxacarb and Spinosad on Liriomyza trifolii (Burgess (Diptera: Agromyzidae in Greenhouse Conditions

    Directory of Open Access Journals (Sweden)

    Ghasem Askari Saryazdi

    2012-01-01

    Full Text Available Liriomyza trifolii is an important pest of vegetable crops in many parts of the worldincluding Iran. In this study potted bean plants were sprayed with recommended fieldrates of abamectin, chlorpyrifos, cyromazine, indoxacarb and spinosad. To assess the residualactivities of these insecticides, the plants were infested with L. trifolii adults 2 hours; 1, 3,5, 7, 10, 15, 20, 25 and 35 days after insecticidal treatments. The adults were allowed to stayon treated plants for eight hours. The treated plants were kept in a greenhouse. Numberof feeding stipples and larval mines on leaves, as well as pupation and adult eclosion rateswere assessed. Two-way ANOVA procedure of SAS was used for statistical analysis andthe treatment means were separated using Duncan’s multiple range test. Abamectin andspinosad severely affected egg hatching and embryonic development. Eggs oviposited inleaves with residues of chlorpyrifos up to 5 days old, had reduced hatching. Larval developmentwas also, affected by residues of chlorpyrifos up to four weeks old. Indoxacarbreduced larval development and adult eclosion in treatments with up to 20 days old residues.Cyromazine had no effect on the number of larval mines, but, pupation was severelyhampered and adult eclosion was completely ceased even in treatments with five weeksold residues. Determining the residual activity of insecticides used for controlling this pestis useful in avoiding unnecessary treatments.

  5. Falling for Clay Leaves.

    Science.gov (United States)

    Kernan, Christine

    2002-01-01

    Describes an art project that integrated science and art education. Explains that students create ceramic bowls by using real leaves. Discusses the process of creating the ceramic bowls, including how to glaze the bowls. Includes a list of materials. (CMK)

  6. Maternity Leave Policies

    Science.gov (United States)

    Strang, Lucy; Broeks, Miriam

    2017-01-01

    Abstract Over recent years many European Union countries have made changes to the design of the maternity leave provision. These policy developments reflect calls for greater gender equality in the workforce and more equal share of childcare responsibilities. However, while research shows that long period of leave can have negative effects on women's labour market attachment and career advancements, early return to work can be seen as a factor preventing exclusive breastfeeding, and therefore, potentially having negative health impacts for babies. Indeed, the World Health Organisation recommends exclusive breastfeeding up to 6 months of age to provide babies with the nutrition for healthy growth and brain development, protection from life-threatening ailments, obesity and non-communicable diseases such as asthma and diabetes. Therefore, labour market demands on women may be at odds with the health benefits for children gained by longer periods of maternity leave. The aim of this article is to examine the relationship between leave provision and health benefits for children. We examine maternity and parental leave provision across European countries and its potential impact on the breastfeeding of very young babies (up to 6-months of age). We also consider economic factors of potential extension of maternity leave provision to 6 months, such as costs to businesses, effects on the female labour market attachment, and wider consequences (benefits and costs) for individuals, families, employers and the wider society. PMID:28983432

  7. Heavy metal toxicities in vegetable crops. VI. The effect of potassium and calcium concentration in the nutrient solution on manganese toxicities in vegetable crops

    Energy Technology Data Exchange (ETDEWEB)

    Osawa, T; Ikeda, H

    1977-01-01

    Eight species of vegetable crops were grown in solution culture in order to investigate the effect of potassium and calcium concentration in the nutrient solution on manganese toxicities in vegetable crops. Manganese was supplied at levels of 0.5, 30, and 100 ppm. At each manganese level potassium or calcium was supplied at rates of 2, 6, and 18 me/l. The pH of the nutrient solution was adjusted to 5. Manganese excess induced interveinal chlorosis on upper leaves in bean, eggplant, pepper, and spinach, and marginal chlorosis on lower leaves in cabbage, lettuce, and celery. In Welsh onions chlorosis was induced on lower leaves. Increasing the supply of potassium and calcium reduced the severity of manganese-induced chlorosis. This beneficial effect was generally more marked with calcium than with potassium. Increasing the supply of potassium and calcium was effective in alleviating the growth reduction of vegetable crops due to manganese excess. This effect also was more marked with calcium than with potassium. With increasing manganese level in the nutrient solution the manganese concentration in leaves of vegetable crops increased. Increasing the supply of potassium and calcium inhibited excessive accumulation of manganese in leaves. The influence of calcium was stronger than that of potassium. In any of the vegetable crops tested, regardless of potassium and calcium treatments, manganese concentration in leaves was closely related to manganese toxicities; the more the accumulation of manganese in leaves increased, the more the severity of manganese-induced chlorosis and growth reduction increased.

  8. Corn residue removal and CO2 emissions

    Science.gov (United States)

    Carbon dioxide (CO2), nitrous oxide (N2O), and methane (CH4) are the primary greenhouse gases (GHG) emitted from the soil due to agricultural activities. In the short-term, increases in CO2 emissions indicate increased soil microbial activity. Soil micro-organisms decompose crop residues and release...

  9. QA/QC in pesticide residue analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ambrus, A [Agrochemicals Unit, Agency' s Laboratories, Seibersdorf (Austria)

    2002-07-01

    This paper outlines problems related to pesticide residue analysis in a regulatory laboratory that are related to: availability of reference materials, as over 1000 pesticide active ingredients are currently in use and over 400 crops represent a large part of a healthy diet; analysis time; availability of samples in sufficient numbers; uncertainties of the procedures.

  10. QA/QC in pesticide residue analysis

    International Nuclear Information System (INIS)

    Ambrus, A.

    2002-01-01

    This paper outlines problems related to pesticide residue analysis in a regulatory laboratory that are related to: availability of reference materials, as over 1000 pesticide active ingredients are currently in use and over 400 crops represent a large part of a healthy diet; analysis time; availability of samples in sufficient numbers; uncertainties of the procedures

  11. THE EFFECT OF HARVESTING TIME AND DEGREE OF LEAVES MATURATION ON VITEKSIKARPIN LEVEL IN LEGUNDI LEAVES (Vitex trifolia L.

    Directory of Open Access Journals (Sweden)

    Yosi Bayu Murti

    2015-11-01

    Full Text Available Legundi (Vitex trifolia L. is one of Indonesia’s traditional crops that have not been studied and developed into fitofarmaka. Legundi leaves can be used for therapy in asthmatics with optimum level. Therefore it is necessary for optimization of harvesting Legundi leaves which includes time and degree of maturation of the leaves. Harvesting time optimization by means of harvesting the leaves at the different times i.e. morning, noon, and evening, while the leaf maturation level optimization by way of harvesting leaves numbered one through five of the youngest end, then the time of harvesting and leaves that provide optimum levels of viteksikarpin were assigned. Measurements of viteksikarpin assigned using TLCdensitometry then analyzed using Wincats software and Microsoft Office Excel 2007. The highest viteksikarpin levels in Legundi leaves harvested in the afternoon, then during the day, and the lowest in the morning. The highest viteksikarpin levels of Legundi leaves were on second leaf, first leaf, third leaf, fourth leaf, and the lowest on fifth leaf. Optimum levels of viteksikarpin in Legundi leaves was harvested in the afternoon by picking the first until the third leaf.

  12. Processing concepts for the use of green leaves as raw materials for the food industry

    NARCIS (Netherlands)

    Tamayo Tenorio, A.; Schreuders, F.K.G.; Zisopoulos, F.K.; Boom, R.M.; Goot, van der A.J.

    2017-01-01

    Large-scale processing of leaves for food applications requires quick processing or stabilisation to avoid perishability, due to the high moisture content in this biomass. Leaf perishability is compounded by the seasonal availability of crops, like sugar beet plants, of which the leaves are regarded

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    A field experiment was carried out in an arable organic cropping system and included a sequence with sole cropped fababean (Vicia faba L.), lupin (Lupinus angustifolius L.), pea (Pisum sativum L.), oat (Avena sativa L.) and pea–oat intercropping with or without an undersown perennial ryegrass...... 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...

  14. Bioenergy from sisal residues

    Energy Technology Data Exchange (ETDEWEB)

    Jungersen, G. [Dansk Teknologisk Inst. (Denmark); Kivaisi, A.; Rubindamayugi, M. [Univ. of Dar es Salaam (Tanzania, United Republic of)

    1998-05-01

    The main objectives of this report are: To analyse the bioenergy potential of the Tanzanian agro-industries, with special emphasis on the Sisal industry, the largest producer of agro-industrial residues in Tanzania; and to upgrade the human capacity and research potential of the Applied Microbiology Unit at the University of Dar es Salaam, in order to ensure a scientific and technological support for future operation and implementation of biogas facilities and anaerobic water treatment systems. The experimental work on sisal residues contains the following issues: Optimal reactor set-up and performance; Pre-treatment methods for treatment of fibre fraction in order to increase the methane yield; Evaluation of the requirement for nutrient addition; Evaluation of the potential for bioethanol production from sisal bulbs. The processing of sisal leaves into dry fibres (decortication) has traditionally been done by the wet processing method, which consumes considerable quantities of water and produces large quantities of waste water. The Tanzania Sisal Authority (TSA) is now developing a dry decortication method, which consumes less water and produces a waste product with 12-15% TS, which is feasible for treatment in CSTR systems (Continously Stirred Tank Reactors). (EG)

  15. 40 CFR 180.627 - Fluopicolide; tolerances for residues.

    Science.gov (United States)

    2010-07-01

    ... combined residues of fluopicolide and its metabolite, 2,6-dichlorobenzamide (BAM). Commodity Parts per... brassica, group 4 25 Vegetable, leaves of root and tuber, group 2 15.0 Vegetable, root, subgroup 1A, except...

  16. Evaluation of Tillage, Residue Management and Nitrogen Fertilizer Effects on CO2 Emission in Maize (Zea Mays L. Cultivation

    Directory of Open Access Journals (Sweden)

    Rooholla Moradi

    2016-02-01

    Full Text Available Introduction: The latest report of the Intergovernmental Panel on Climate Change (IPCC states that future emissions of greenhouse gases (GHGs will continue to increase and cause climatic change (16. These conditions are also true for Iran. The three greenhouse gases associated with agriculture are carbon dioxide (CO2, methane (CH4, and nitrous oxide (N2O. The three GHGs associated with agriculture CO2, CH4, and N2O differ in their effectiveness in trapping heat and in their turnover rates in the atmosphere. This environmental change will have serious impacts on different growth and development processes of crops. Increasing temperature could affect physiological processes such as photosynthesis, respiration and partitioning of photoassimilates. Farmers are not able to change or manage the climatic conditions, but some factors such as soil, water, seed and agricultural practices can be managed to reduce the adverse impacts of climate change (32. Mitigation and adaptation are two known ways for reducing the negative impacts of climate change. Mitigation strategies are associated with decreasing greenhouse gas (GHG emissions through management practices such as reducing chemical fertilizer application, mechanization, increasing carbon storage in agroecosystems, planting biofuel crops and moving towards organic farming (42, etc. Material and Methods: This study was carried out at the experimental field of the Ferdowsi University of Mashhad in 2011 and was repeated in 2012. The Research Station (36°16´N, 59°36´E is located at about 985 m a.s.l. Average temperature and precipitation rate of the research station in two years are shown in Figure. 1. The three-factor experiment was set up in a strip-split-plot arranged in a randomized complete block design with three replications. The experimental treatments were tillage systems (conventional and reduced tillage and residual management (remaining and leaving of maize residual assigned to main plots

  17. Produção de fitomassa por plantas de cobertura e mineralização de seus resíduos em plantio direto Cover crops biomass production and its residues mineralization in a Brazilian no-till Oxisol

    Directory of Open Access Journals (Sweden)

    Jose Luiz Rodrigues Torres

    2008-03-01

    Full Text Available O objetivo deste trabalho foi avaliar a produção de fitomassa seca, a taxa de decomposição das palhadas e as quantidades de macronutrientes (N, P, Ca, Mg e S liberadas dos resíduos vegetais de sete plantas de cobertura de solo, em condições de Cerrado, por dois anos. As plantas de cobertura avaliadas foram: milheto (Pennisetum americanum sin. typhoides, braquiária (Brachiaria brizantha cv. Marandu, sorgo forrageiro [Sorghum bicolor (L. Moench], guandu [Cajanus cajan (L. Millsp.], crotalária juncea (Crotalaria juncea L., aveia-preta (Avena strigosa Schreb e a vegetação espontânea de uma parcela em pousio. Utilizou-se o delineamento em blocos ao acaso, com quatro repetições, implantado em um Latossolo Vermelho, textura média. Avaliou-se a produção de fitomassa seca 110 dias após a semeadura. A taxa de decomposição foi quantificada por meio de sacolas de náilon contendo os resíduos culturais, coletadas em intervalos regulares. Observou-se que milheto e crotalária são as coberturas gramínea e leguminosa com maior produção de fitomassa seca e acúmulo de N, nos dois períodos avaliados. A maior taxa de decomposição das plantas de cobertura e de liberação de nutrientes ocorre aos 42 dias após a dessecação. Os maiores tempos de meia-vida foram observados no período de menor precipitação pluvial.The objective of this work was to evaluate dry biomass production, decomposition rate and macronutrients release (N, P, Ca, Mg and S of cover crops cultural residues, in a no-till savanna soil. The cover crops tested were: pearl millet (Pennisetum americanum sin. typhoides, brachiaria grass (Brachiaria brizantha cv. Marandu, sorghum [Sorghum bicolor (L. Moench], pigeon pea [Cajanus cajan (L. Millsp.], sunn hemp (Crotalaria juncea L. and black oat (Avena strigosa Schreb, compared to a fallow plot (control. The experiment was carried out in an Oxisol, medium texture. A randomized block design, in a split-plot array in time

  18. Biochemical Disincentives to Fertilizing Cellulosic Ethanol Crops

    Science.gov (United States)

    Gallagher, M. E.; Hockaday, W. C.; Snapp, S.; McSwiney, C.; Baldock, J.

    2010-12-01

    Corn grain biofuel crops produce the highest yields when the cropping ecosystem is not nitrogen (N)-limited, achieved by application of fertilizer. There are environmental consequences for excessive fertilizer application to crops, including greenhouse gas emissions, hypoxic “dead zones,” and health problems from N runoff into groundwater. The increase in corn acreage in response to demand for alternative fuels (i.e. ethanol) could exacerbate these problems, and divert food supplies to fuel production. A potential substitute for grain ethanol that could reduce some of these impacts is cellulosic ethanol. Cellulosic ethanol feedstocks include grasses (switchgrass), hardwoods, and crop residues (e.g. corn stover, wheat straw). It has been assumed that these feedstocks will require similar N fertilization rates to grain biofuel crops to maximize yields, but carbohydrate yield versus N application has not previously been monitored. We report the biochemical stocks (carbohydrate, protein, and lignin in Mg ha-1) of a corn ecosystem grown under varying N levels. We measured biochemical yield in Mg ha-1 within the grain, leaf and stem, and reproductive parts of corn plants grown at seven N fertilization rates (0-202 kg N ha-1), to evaluate the quantity and quality of these feedstocks across a N fertilization gradient. The N fertilization rate study was performed at the Kellogg Biological Station-Long Term Ecological Research Site (KBS-LTER) in Michigan. Biochemical stocks were measured using 13C nuclear magnetic resonance spectroscopy (NMR), combined with a molecular mixing model (Baldock et al. 2004). Carbohydrate and lignin are the main biochemicals of interest in ethanol production since carbohydrate is the ethanol feedstock, and lignin hinders the carbohydrate to ethanol conversion process. We show that corn residue carbohydrate yields respond only weakly to N fertilization compared to grain. Grain carbohydrate yields plateau in response to fertilization at

  19. Availability of crop cellulosics for ethanol production

    Energy Technology Data Exchange (ETDEWEB)

    Hayes, R.D.

    1982-10-01

    Past estimates of cellulosic resources available from Canadian agriculture totalled over 23 million tonnes of cereal grain straw and corn stover residues surplus to soil and animal requirements. A new much reduced estimate, based on four detailed regional studies that also include previously unassessed resources such as chaff, oilseed hulls, and food processing wastes, is suggested. Eleven million tonnes are currently available from all residue sources for energy conversion by different processes. Only five million tonnes are identified as potentially usable in ethanol production plants were they to be constructed. Additional resource opportunities may become available in future from currently underutilized land, especially saline soils, novel processing techniques of conventional grains and forages, innovative cropping systems that may increase the yield of agricultural biomass, and new food/feed/fuel (i.e. multi-purpose) crops such as kochia, milkweed, and Jerusalem artichoke. 27 refs., 1 fig., 1 tab.

  20. Humic substances and its distribution in coffee crop under cover crops and weed control methods

    Directory of Open Access Journals (Sweden)

    Bruno Henrique Martins

    2016-08-01

    Full Text Available ABSTRACT Humic substances (HS comprise the passive element in soil organic matter (SOM, and represent one of the soil carbon pools which may be altered by different cover crops and weed control methods. This study aimed to assess HS distribution and characteristics in an experimental coffee crop area subjected to cover crops and cultural, mechanical, and chemical weed control. The study was carried out at Londrina, in the state of Paraná, southern Brazil (23°21’30” S; 51°10’17” W. In 2008, seven weed control/cover crops were established in a randomized block design between two coffee rows as the main-plot factor per plot and soil sampling depths (0-10 cm, 10-20 cm, 20-30 cm and 30-40 cm as a split-plot. HS were extracted through alkaline and acid solutions and analyzed by chromic acid wet oxidation and UV-Vis spectroscopy. Chemical attributes presented variations in the topsoil between the field conditions analyzed. Cover crop cutting and coffee tree pruning residues left on the soil surface may have interfered in nutrient cycling and the humification process. Data showed that humic substances comprised about 50 % of SOM. Although different cover crops and weed control methods did not alter humic and fulvic acid carbon content, a possible incidence of condensed aromatic structures at depth increments in fulvic acids was observed, leading to an average decrease of 53 % in the E4/E6 ratio. Humin carbon content increased 25 % in the topsoil, particularly under crop weed-control methods, probably due to high incorporation of recalcitrant structures from coffee tree pruning residues and cover crops.

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

    African Journals Online (AJOL)

    significant effects on food crop production and productivity. ... 2 Department of Economics and Resource management, Norwegian University of Life Sciences, Norway ... food markets work well, the problem of imperfect markets does not allow ..... prices at the time of purchase with the remaining balance due at the end of the.

  2. Cover crop root, shoot, and rhizodeposit contributions to soil carbon in a no- till corn bioenergy cropping system

    Science.gov (United States)

    Austin, E.; Grandy, S.; Wickings, K.; McDaniel, M. D.; Robertson, P.

    2016-12-01

    Crop residues are potential biofuel feedstocks, but residue removal may result in reduced soil carbon (C). The inclusion of a cover crop in a corn bioenergy system could provide additional biomass and as well as help to mitigate the negative effects of residue removal by adding belowground C to stable soil C pools. In a no-till continuous corn bioenergy system in the northern portion of the US corn belt, we used 13CO2 pulse labeling to trace C in a winter rye (secale cereale) cover crop into different soil C pools for two years following rye termination. Corn stover contributed 66 (another 163 was in harvested corn stover), corn roots 57, rye shoot 61, rye roots 59, and rye rhizodeposits 27 g C m-2 to soil C. Five months following cover crop termination, belowground cover crop inputs were three times more likely to remain in soil C pools and much of the root-derived C was in mineral- associated soil fractions. Our results underscore the importance of cover crop roots vs. shoots as a source of soil C. Belowground C inputs from winter cover crops could substantially offset short term stover removal in this system.

  3. Gender in crop agriculture

    OpenAIRE

    Food and Agriculture Organization; The World Bank; IFAD

    2008-01-01

    Metadata only record This is a module in the "Gender in Agriculture Sourcebook" published by the World Bank, UN Food and Agriculture Organization, and International Fund for Agricultural Development. This module examines the role of gender in crop agriculture as an essential component of development and poverty reduction. Gender is an integral aspect of crop agriculture because women's roles in crop production and household subsistence, as well as their knowledge of complex production syst...

  4. Corn residue utilization by livestock in the USA

    Science.gov (United States)

    Corn (Zea mays L.) residue grazing or harvest provides a simple and economical practice to integrate crops and livestock. Limited information is available on how widespread corn residue utilization is practiced by US producers. In 2010, the USDA-ERS surveyed producers from 19 states on corn grain ...

  5. TRAVEL AND HOME LEAVE

    CERN Multimedia

    Human Resources Division

    2002-01-01

    Administrative procedures for : Travel to the home station and home leave (hl) Additional travel to the home station (at) Travel to the home station and home leave for family reasons (hlf) As part of the process of simplifying administrative procedures, HR and AS Divisions have devised a new, virtually automatic procedure for payment of travel expenses to the home station. The changes are aimed at rationalising administrative procedures and not at reducing benefits. The conditions of eligibility are unchanged. The new procedure, which will be operational with effect from 1st June 2002, will greatly simplify the administrative processing of claims for travel expenses and the recording of home leaves. Currently, requests for payment are introduced manually into the Advances and Claims system (AVCL) by divisional secretariats. All travel to the home station starting prior to 1st June 2002 will be processed according to the existing system whereas that starting on 1st June and after will be processed accordi...

  6. Residual nilpotence and residual solubility of groups

    International Nuclear Information System (INIS)

    Mikhailov, R V

    2005-01-01

    The properties of the residual nilpotence and the residual solubility of groups are studied. The main objects under investigation are the class of residually nilpotent groups such that each central extension of these groups is also residually nilpotent and the class of residually soluble groups such that each Abelian extension of these groups is residually soluble. Various examples of groups not belonging to these classes are constructed by homological methods and methods of the theory of modules over group rings. Several applications of the theory under consideration are presented and problems concerning the residual nilpotence of one-relator groups are considered.

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    systems based on fertility building crops (green manures and catch crops). In short, the main distinctions were not observed between organic and conventional systems (i.e. C vs. O1, O2 and O3), but between systems based mainly on nutrient import vs. systems based mainly on fertility building crops (C...... of the organic rotation, both relying on green manures and catch crops grown during the autumn after the main crop as their main source of soil fertility, and the O3 system further leaving rows of the green manures to grow as intercrops between vegetable rows to improve the conditions for biodiversity...... 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...

  8. Does Leave Work?

    NARCIS (Netherlands)

    Heleen van Luijn; Saskia Keuzenkamp

    2004-01-01

    More and more people have to combine work and care responsibilities, and work part-time or use daycare and after-school care facilities to help them do so. The Work and Care Act, which came into force on 1 December 2001, combined all the existing schemes - such as parental and maternity leave -

  9. Maternity Leave in Taiwan

    Science.gov (United States)

    Feng, Joyce Yen; Han, Wen-Jui

    2010-01-01

    Using the first nationally representative birth cohort study in Taiwan, this paper examines the role that maternity leave policy in Taiwan plays in the timing of mothers returning to work after giving birth, as well as the extent to which this timing is linked to the amount of time mothers spend with their children and their use of breast milk…

  10. REMINDER: Saved Leave Scheme (SLS)

    CERN Multimedia

    2003-01-01

    Transfer of leave to saved leave accounts Under the provisions of the voluntary saved leave scheme (SLS), a maximum total of 10 days'* annual and compensatory leave (excluding saved leave accumulated in accordance with the provisions of Administrative Circular No 22B) can be transferred to the saved leave account at the end of the leave year (30 September). We remind you that unused leave of all those taking part in the saved leave scheme at the closure of the leave year accounts is transferred automatically to the saved leave account on that date. Therefore, staff members have no administrative steps to take. In addition, the transfer, which eliminates the risk of omitting to request leave transfers and rules out calculation errors in transfer requests, will be clearly shown in the list of leave transactions that can be consulted in EDH from October 2003 onwards. Furthermore, this automatic leave transfer optimizes staff members' chances of benefiting from a saved leave bonus provided that they ar...

  11. Lead, arsenic, and copper content of crops grown on lead arsenate-treated and untreated soils

    Energy Technology Data Exchange (ETDEWEB)

    Chisholm, D

    1972-01-01

    Increased lead and arsenic concentrations in the surface soil (0-15 cm), resulting from applications of lead arsenate (PbHAs0/sub 1/), increased both lead and arsenic levels in crops grown on treated plots. The lead levels in some crops approached or exceeded the Canadian residue tolerance of 2.0 ppM. Lead arsenate soil treatments did not affect copper absorption by crops. On areas such as old orchard land contaminated with lead arsenate residues it may be advisable to ascertain crops, and also to determine the lead affinity and arsenic sensitivity of the plants to be grown.

  12. Numerical simulation of cropping

    DEFF Research Database (Denmark)

    Tvergaard, Viggo; Hutchinson, John W.

    2014-01-01

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

  13. Applied Crop Protection 2017

    DEFF Research Database (Denmark)

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

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

  14. Applied Crop Protection 2017

    DEFF Research Database (Denmark)

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

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

  15. Applied crop protection 2016

    DEFF Research Database (Denmark)

    Jørgensen, Lise Nistrup; Nielsen, Bent Jørgen; Jensen, Peter Kryger

    This publication contains results from crop protection trials which were carried out at the Department of Agroecology within the area of agricultural crops. Most of the results come from field trials, but results from greenhouse and semi-field trials are also included. The report contains results...

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

    International Nuclear Information System (INIS)

    Mann, R.A.; Munir, M.; Haqqani, A.M.

    2004-01-01

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

  17. Alternative Crops and Biofuel Production

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-03-01

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

  18. Injury to crops by gas as produced from plastic materials

    Energy Technology Data Exchange (ETDEWEB)

    Inden, T; Tachibana, S

    1971-01-01

    The effects of gas formations of phthalate and epoxy plasticizers on crops were studied at room temperature and 100 to 200 C. The materials were tested either alone Or as products including polyvinyl chloride and a stabilizer. At room temperature, dioctylphthalate (DOP) did not injure the cucumber leaves, whereas diisobutyl phthalate (DIBF) injured 74.1%, and dibutyl phthalate injured 36.5% of the surface of the leaves. Among many stabilizers tested, triphenyl phosphite injured 80% of the surface area of cucumber leaves. At 100 C to 200 C for 48 hours DIBP and CLP injured the Chinese cabbage leaves most, about 80% of the surface area. The following chemicals for the manufacturing of the plasticizers were also found to injure Chinese cabbage leaves, isobutanol 18.3%, 2-ethyl-hexanol 98.3%, isodecanol 98.5%, phthalic acid 40.0, and adipic acid 6.6%.

  19. Soil carbon fractions in response to long-term crop rotations in the Loess Plateau of China

    Science.gov (United States)

    Diversified crop rotations may enhance C fractions and soil quality by affecting the quality and quantity of crop residue returned to the soil compared with monocropping and fallow. We evaluated the effect of 30-yr-old diversified crop rotations on soil C fractions at 0- to 15- and 15- to 30-cm dept...

  20. Process to recycle shredder residue

    Science.gov (United States)

    Jody, Bassam J.; Daniels, Edward J.; Bonsignore, Patrick V.

    2001-01-01

    A system and process for recycling shredder residue, in which separating any polyurethane foam materials are first separated. Then separate a fines fraction of less than about 1/4 inch leaving a plastics-rich fraction. Thereafter, the plastics rich fraction is sequentially contacted with a series of solvents beginning with one or more of hexane or an alcohol to remove automotive fluids; acetone to remove ABS; one or more of EDC, THF or a ketone having a boiling point of not greater than about 125.degree. C. to remove PVC; and one or more of xylene or toluene to remove polypropylene and polyethylene. The solvents are recovered and recycled.

  1. Nutritive Value Assessment of Four Crop Residues by Proximate ...

    African Journals Online (AJOL)

    Dr Grace Tona

    Ladoke Akintola University of Technology, P.M.B. 4000, Ogbomoso, Nigeria ... Abstract. This study estimated the proximate composition and in vitro gas production parameters of rice husk, bean ... farms and industries generate large quantities.

  2. Evaluation of crop residue retention, compost and inorganic fertilizer ...

    African Journals Online (AJOL)

    Soil fertility depletion is a serious problem in the highlands of Ethiopia. ... The design was randomized complete block with three replications. ... were obtained from the applications of the recommended nitrogen and phosphorus (NP) fertilizer ...

  3. Improved anaerobic digestion of energy crops and agricultural residues

    DEFF Research Database (Denmark)

    Bruni, Emiliano

    Formålet med dette ph.d.-studie var at finde metoder til at forbedre effektiviteten af biogasprocessen ved at følge 2 strategier: a) at forøge bionedbrydeligheden af svært nedbrydelige biofibre (lignocellulosisk materiale) ved anvendelse af biologisk, kemisk, mekanisk eller dampbehandling; b) at ...

  4. the utilization of crop residues and animal wastes by ruminants

    African Journals Online (AJOL)

    c. Swelling of microfibriallae results in disruption of the crystalline structure of cellulose. This probably gives rise to .... material for cattle (Lombard, personal communication). Although .... Rumen Physiology Ed.McDonald. University New ...

  5. Utilization of crop residue and animal wastes among agropastoral ...

    African Journals Online (AJOL)

    Journal Home > Vol 7 (2009) > ... Quantitative data collection method was used with the aid of a well structured questionnaire with both open and close ended ... But their wives and children used chicken waste as manure on vegetable farms.

  6. Small holder lamb fattening based on crop residues and agro ...

    African Journals Online (AJOL)

    Ghana Journal of Agricultural Science ... a total of 29 intact rams (DjallonkeW Sahelian) were fattened on two diets formulated from rice straw (urea-treated), pigeon pea waste, dry cassava peels and whole cottonseed. In Diet 1, cassava peels constituted the basal ingredient while in Diet 2, pigeon pea waste was major.

  7. Environmental risk assessments for transgenic crops producing output trait enzymes

    Science.gov (United States)

    Tuttle, Ann; Shore, Scott; Stone, Terry

    2009-01-01

    The environmental risks from cultivating crops producing output trait enzymes can be rigorously assessed by testing conservative risk hypotheses of no harm to endpoints such as the abundance of wildlife, crop yield and the rate of degradation of crop residues in soil. These hypotheses can be tested with data from many sources, including evaluations of the agronomic performance and nutritional quality of the crop made during product development, and information from the scientific literature on the mode-of-action, taxonomic distribution and environmental fate of the enzyme. Few, if any, specific ecotoxicology or environmental fate studies are needed. The effective use of existing data means that regulatory decision-making, to which an environmental risk assessment provides essential information, is not unnecessarily complicated by evaluation of large amounts of new data that provide negligible improvement in the characterization of risk, and that may delay environmental benefits offered by transgenic crops containing output trait enzymes. PMID:19924556

  8. Response of Sorghum bicolor L. to Residual Phosphate on Two Contrasting Soils Previously Planted to Cowpea or Maize

    Directory of Open Access Journals (Sweden)

    Tola Omolayo Olasunkanmi

    2016-01-01

    Full Text Available Proper fertilizer nutrient management through adequate utilization of the residual value coupled with healthy crop rotation contributes significantly to sustainable crop production. This study was conducted to evaluate the direct and residual effects of two rock phosphate (RP materials on two contrasting soils previously planted with either the cereal crop or the leguminous crop. The effectiveness of the RP materials as substitute for the conventional P fertilizers was evaluated using single superphosphate as reference at the Department of Agronomy, University of Ibadan, Ibadan, Nigeria. The experiments were 2 × 2 × 4 factorial in completely randomized design. The test crops in the first cropping performed better on the slightly acidic loamy sand than on the strongly acidic sandy clay loam. Performance of each crop was improved by P supply in the first and second cropping. Single superphosphate proved to be more efficient than the RPs in the first cropping but not as effective as MRP in the second cropping. In the second cropping, sorghum performed better on the soil previously cropped to cowpea while Morocco RP had the highest residual effect among the P-fertilizer sources. It is evident that rock phosphates are better substitutes to the conventional phosphorus fertilizers due to their long term residual effect in soils. The positive effects of healthy rotation of crops as well as the negative effects of low soil pH are also quite obvious.

  9. Effects of Adopting Different Kinds of Collecting Method for Years on Film Residual Coefficient and Maize Yields

    OpenAIRE

    TANG Wen-xue; MA Zhong-ming; WEI Tao

    2017-01-01

    Wide usage of mulching technology has increased crop yields, but the large amounts of mulching film residue resulting from widespread use of plastic film in China has brought about a series of pollution hazards. Based on a 4-year (2011-2014) long-term experiment, the effects of different kinds of collecting mothod (zero plastic film residues, conventional plastic film residues, whole plastic film residues remainded) on plastic film residues, residual coefficient and maize yield were explored....

  10. Employer Provisions for Parental Leave.

    Science.gov (United States)

    Meisenheimer, Joseph R., II

    1989-01-01

    Slightly more than one-third of full-time employees in medium and large firms in private industry were covered by maternity- or paternity-leave policies; days off were usually leave without pay. (Author)

  11. The comparison of nitrogen use and leaching in sole cropped versus intercropped pea and barley

    DEFF Research Database (Denmark)

    Hauggaard-Nielsen, H.; Ambus, P.; Jensen, E.S.

    2003-01-01

    The effect of sole and intercropping of field pea (Pisum sativum L.) and spring barley (Hordeum vulgare L.) and of crop residue management on crop yield, NO3- leaching and N balance in the cropping system was tested in a 2-year lysimeter experiment on a temperate sandy loam soil. The crop rotation...... cropping. Crops received no fertilizer in the experimental period. Natural N-15 abundance techniques were used to determine pea N-2 fixation. The pea-barley intercrop yielded 4.0 Mg grain ha(-1), which was about 0.5 Mg lower than the yields of sole cropped pea but about 1.5 Mg greater than harvested...... was pea and barley sole and intercrops followed by winter-rye and a fallow period. The Land Equivalent Ratio (LER), which is defined as the relative land area under sole crops that is required to produce the yields achieved in intercropping, was used to compare intercropping performance relative to sole...

  12. Cover Crops Effects on Soil Chemical Properties and Onion Yield

    Directory of Open Access Journals (Sweden)

    Rodolfo Assis de Oliveira

    2016-01-01

    Full Text Available ABSTRACT Cover crops contribute to nutrient cycling and may improve soil chemical properties and, consequently, increase crop yield. The aim of this study was to evaluate cover crop residue decomposition and nutrient release, and the effects of these plants on soil chemical properties and on onion (Allium cepa L. yield in a no-tillage system. The experiment was carried out in an Inceptisol in southern Brazil, where cover crops were sown in April 2012 and 2013. In July 2013, shoots of weeds (WD, black oats (BO, rye (RY, oilseed radish (RD, oilseed radish + black oats (RD + BO, and oilseed radish + rye (RD + RY were cut at ground level and part of these material from each treatment was placed in litter bags. The litter bags were distributed on the soil surface and were collected at 0, 30, 45, 60, 75, and 90 days after distribution (DAD. The residues in the litter bags were dried, weighed, and ground, and then analyzed to quantify lignin, cellulose, non-structural biomass, total organic carbon (TOC, N, P, K, Ca, and Mg. In November 2012 and 2013, onion crops were harvested to quantify yield, and bulbs were classified according to diameter, and the number of rotted and flowering bulbs was determined. Soil in the 0.00-0.10 m layer was collected for chemical analysis before transplanting and after harvesting onion in December 2012 and 2013. The rye plant residues presented the highest half-life and they released less nutrients until 90 DAD. The great permanence of rye residue was considered a protection to soil surface, the opposite was observed with spontaneous vegetation. The cultivation and addition of dry residue of cover crops increased the onion yield at 2.5 Mg ha-1.

  13. African Crop Science Journal

    African Journals Online (AJOL)

    AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING AJOL ... The African Crop Science Journal, a quarterly publication, publishes original ... interactions, information science, environmental science and soil science.

  14. African Crop Science Journal

    African Journals Online (AJOL)

    African Crop Science Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 1, No 2 (1993) >. Log in or Register to get access to full text downloads.

  15. African Crop Science Journal

    African Journals Online (AJOL)

    African Crop Science Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 22 (2014) >. Log in or Register to get access to full text downloads.

  16. REMINDER Saved Leave Scheme (SLS) : Transfer of leave to saved leave accounts

    CERN Multimedia

    HR Division

    2002-01-01

    Under the provisions of the voluntary saved leave scheme (SLS), a maximum total of 10 days'*) annual and compensatory leave (excluding saved leave accumulated in accordance with the provisions of Administrative Circular No. 22B) can be transferred to the saved leave account at the end of the leave year (30 September). We remind you that, since last year, unused leave of all those taking part in the saved leave scheme at the closure of the leave-year accounts is transferred automatically to the saved leave account on that date. Therefore, staff members have no administrative steps to take. In addition, the transfer, which eliminates the risk of omitting to request leave transfers and rules out calculation errors in transfer requests, will be clearly shown in the list of leave transactions that can be consulted in EDH from October 2002 onwards. Furthermore, this automatic leave transfer optimizes staff members' chances of benefiting from a saved leave bonus provided that they are still participants in the schem...

  17. Saved Leave Scheme (SLS) : Simplified procedure for the transfer of leave to saved leave accounts

    CERN Multimedia

    HR Division

    2001-01-01

    As part of the process of streamlining procedures, the HR and AS Divisions have jointly developed a system whereby annual and compensatory leave will henceforth be automatically transferred1) to saved leave accounts. Under the provisions of the voluntary saved leave scheme (SLS), a maximum total of 10 days'2) annual and compensatory leave (excluding saved leave accumulated in accordance with the provisions of Administrative Circular No. 22 B) can be transferred to the saved leave account at the end of the leave year (30 September). Previously, every person taking part in the scheme has been individually issued with a form for the purposes of requesting the transfer of leave to the leave account and the transfer has then had to be done manually by HR Division. To streamline the procedure, unused leave of all those taking part in the saved leave scheme at the closure of of the leave-year accounts will henceforth be transferred automatically to the saved leave account on that date. This simplification is in the ...

  18. Radioactivity in food crops

    International Nuclear Information System (INIS)

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

    1983-05-01

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

  19. Radioactivity in food crops

    Energy Technology Data Exchange (ETDEWEB)

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

    1983-05-01

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

  20. one of the keys to attaining and sustaining higher crop yields

    African Journals Online (AJOL)

    Interim fertiliser recommendations for different crops at selected locations in Uganda. ... However, these recommendations (Table 5) need updating to reflect the decline in soil fertility ... and have longer residual effects in soil compared to high.

  1. Addressing crop interactions within cropping systems in LCA

    DEFF Research Database (Denmark)

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

    2018-01-01

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

  2. A Review on Recycling of Sunflower Residue for Sustaining Soil Health

    Directory of Open Access Journals (Sweden)

    Subhash Babu

    2014-01-01

    Full Text Available Modern agriculture is now at the crossroads ecologically, economically, technologically, and socially due to soil degradation. Critical analysis of available information shows that problems of degradation of soil health are caused due to imbalanced, inadequate and promacronutrient fertilizer use, inadequate use or no use of organic manures and crop residues, and less use of good quality biofertilizers. Although sizeable amount of crop residues and manure is produced in farms, it is becoming increasingly complex to recycle nutrients, even within agricultural systems. Therefore, there is a need to use all available sources of nutrients to maintain the productivity and fertility at a required level. Among the available organic sources of plant nutrients, crop residue is one of the most important sources for supplying nutrients to the crop and for improving soil health. Sunflower is a nontraditional oil seed crop produced in huge amount of crop residue. This much amount of crop residues is neither used as feed for livestock nor suitable for fuel due to low energy value per unit mass. However, its residue contains major plant nutrients in the range from 0.45 to 0.60% N, 0.15 to 0.22% P, and 1.80 to 1.94% K along with secondary and micronutrients, so recycling of its residue in the soil may be one of the best alternative practices for replenishing the depleted soil fertility and improving the physical, chemical, and biological properties of the soil in the present era of production. However, some researchers have reported allelopathic effects of sunflower residue on different crops. So, selection of suitable crops and management practices may play an important role to manage the sunflower residue at field level.

  3. Residual stress concerns in containment analysis

    International Nuclear Information System (INIS)

    Costantini, F.; Kulak, R. F.; Pfeiffer, P. A.

    1997-01-01

    The manufacturing of steel containment vessels starts with the forming of flat plates into curved plates. A steel containment structure is made by welding individual plates together to form the sections that make up the complex shaped vessels. The metal forming and welding process leaves residual stresses in the vessel walls. Generally, the effect of metal forming residual stresses can be reduced or virtually eliminated by thermally stress relieving the vesseL In large containment vessels this may not be practical and thus the residual stresses due to manufacturing may become important. The residual stresses could possibly tiect the response of the vessel to internal pressurization. When the level of residual stresses is significant it will affect the vessel's response, for instance the yielding pressure and possibly the failure pressure. The paper will address the effect of metal forming residual stresses on the response of a generic pressure vessel to internal pressurization. A scoping analysis investigated the effect of residual forming stresses on the response of an internally pressurized vessel. A simple model was developed to gain understanding of the mechanics of the problem. Residual stresses due to the welding process were not considered in this investigation

  4. Residual Acute Toxicity of Some Modern Insecticides Toward Two Mirid Predators of Tomato Pests.

    Science.gov (United States)

    Wanumen, Andrea C; Carvalho, Geraldo A; Medina, Pilar; Viñuela, Elisa; Adán, Ángeles

    2016-03-31

    The successful integration of chemical and biological control strategies for crop pests depends on a thorough evaluation of the effects of pesticides on the natural enemies of pests. A case-by-case review is difficult to achieve because of the many combinations of pests, natural enemies, and crops that need to be tested. Within this framework, we tested and compared seven insecticides representative of four different modes of action (MoAs) groups on closely related predators (Miridae): flubendiamide, spirotetramat, metaflumizone, and sulfoxaflor onNesidiocoris tenuisReuter and flubendiamide, spiromesifen, indoxacarb, and imidacloprid onMacrolophus basicornis(Stal). We follow the standardized methodology of the International Organization for Biological Control, a sequential testing exposure scheme. The lethal effect of each insecticide was evaluated in adults after three days of contact with treated surfaces in the laboratory, extended laboratory, and semifield tests (inert substrate, tomato leaves, and tomato plant as the treated surface, respectively). Flubendiamide, spiromesifen, and spirotetramat were classified as harmless (class 1), metaflumizone was slightly harmful (class 2) but persistent, indoxacarb was harmless (class 1), and sulfoxaflor and imidacloprid were toxic (class 4) and exhibited a long residual activity. Our results suggest similarities in the acute toxicities of insecticides from the same MoA group on related species of natural enemies. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. The Giant Reed as an energy crop: assessing the energy requirements within its supply chain

    DEFF Research Database (Denmark)

    Rodias, Efthymis; Busato, P.; Bochtis, Dionysis

    2013-01-01

    Biomass energy is one form of renewable energy sources that are in the core of interesting for many researchers. There many different biomass sources that can be exploited for energy production, such as crop residues, waste materials, forestry residues and energy crops. Regarding energy crops......, there are many different types of crops significantly varies in terms of energy potential yields, production and provision methods, etc. To this end, a thoroughly assessment of the energy inputs and outputs of each potential energy crop is necessary. In this paper, the Giant Reed is evaluated energetically...... as a potential energy crop. The assessment regards a 10 year period. The considered energy elements include direct inputs (e.g. fuel consumption) as well as indirect inputs (e.g. embodied energy of materials and machinery). According to the results, the balance between the estimated total energy input...

  6. Modelling the carbon and nitrogen balances of direct land use changes from energy crops in Denmark

    DEFF Research Database (Denmark)

    Hamelin, Lorie; Jørgensen, Uffe; Petersen, Bjørn Molt

    2012-01-01

    This paper addresses the conversion of Danish agricultural land from food/feed crops to energy crops. To this end, a life cycle inventory, which relates the input and output flows from and to the environment of 528 different crop systems, is built and described. This includes seven crops (annuals...... and perennials), two soil types (sandy loam and sand), two climate types (wet and dry), three initial soil carbon level (high, average, low), two time horizons for soil carbon changes (20 and 100 years), two residues management practices (removal and incorporation into soil) as well as three soil carbon turnover...... rate reductions in response to the absence of tillage for some perennial crops (0%, 25%, 50%). For all crop systems, nutrient balances, balances between above- and below-ground residues, soil carbon changes, biogenic carbon dioxide flows, emissions of nitrogen compounds and losses of macro...

  7. Grand challenges for crop science

    Science.gov (United States)

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

  8. Biotechnology: herbicide-resistant crops

    Science.gov (United States)

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

  9. Parental leave and child health.

    Science.gov (United States)

    Ruhm, C J

    2000-11-01

    This study investigates whether rights to parental leave improve pediatric health. Aggregate data are used for 16 European countries over the 1969 through 1994 period. More generous paid leave is found to reduce deaths of infants and young children. The magnitudes of the estimated effects are substantial, especially where a causal effect of leave is most plausible. In particular, there is a much stronger negative relationship between leave durations and post-neonatal or child fatalities than for perinatal mortality, neonatal deaths, or low birth weight. The evidence further suggests that parental leave may be a cost-effective method of bettering child health.

  10. Energy from field crops

    Energy Technology Data Exchange (ETDEWEB)

    Zubr, J.

    1990-04-15

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

  11. Phytotoxicity of water-soluble substances from alfalfa and barley soil extracts on four crop species.

    Science.gov (United States)

    Read, J J; Jensen, E H

    1989-02-01

    Problems associated with continuously planting alfalfa (Medicago saliva L.) or seeding to thicken depleted alfalfa stands may be due to autotoxicity, an intraspecific form of allelopathy. A bioassay approach was utilized to characterize the specificity and chemical nature of phytotoxins in extracts of alfalfa soils as compared to fallow soil or soil where a cereal was the previous crop. In germination chamber experiments, water-soluble substances present in methanol extracts of soil cropped to alfalfa or barley (Hordeum vulgare L.) decreased seedling root length of alfalfa L-720, winter wheat (Triticum aestivum L. Nugaines) and radish (Raphanus sativa L. Crimson Giant). Five days after germination, seedling dry weights of alfalfa and radish in alfalfa soil extracts were lower compared to wheat or red clover (Trifolium pralense L. Kenland). Growth of red clover was not significantly reduced by soil extracts from cropped soil. Extracts of crop residue screened from soil cropped to alfalfa or barley significantly reduced seedling root length; extracts of alfalfa residue caused a greater inhibition of seedling dry weight than extracts of barely residue. A phytotoxic, unidentified substance present in extracts of crop residue screened from alfalfa soil, which inhibited seedling root length of alfalfa, was isolated by thin-layer chromatography (TLC). Residues from a soil cropped continuously to alfalfa for 10 years had the greatest phytotoxic activity.

  12. The prevalence of sick leave

    DEFF Research Database (Denmark)

    Backhausen, Mette; Damm, Peter; Bendix, Jane

    2018-01-01

    of long-term sick leave. Method Data from 508 employed pregnant women seeking antenatal care was collected by questionnaires from August 2015 to March 2016. The questionnaires, which were filled in at 20 and 32 weeks of gestation, provided information on maternal characteristics, the number of days spent...... on sick leave and the associated reasons. Descriptive statistics and logistic regression analysis were applied. Results The prevalence of sick leave was 56% of employed pregnant women in the first 32 weeks of gestation and more than one in four reported long-term sick leave (>20 days, continuous...... was a negative predictor. Conclusions The prevalence of sick leave was 56% in the first 32 weeks of gestation and more than one in four women reported long-term sick leave. The majority of reasons for sick leave were pregnancy-related and low back pain was the most frequently given reason....

  13. An early-killed rye cover crop has potential for weed management in edamame

    Science.gov (United States)

    The potential role of fall-seeded cover crops for weed management in edamame is unknown. Field experiments were conducted over three edamame growing seasons to test the following objectives: 1) determine the extent to which cover crop residue management systems influence edamame emergence while sele...

  14. Effects of cover crops on the nitrogen fluxes in a silage maize production system

    NARCIS (Netherlands)

    Schröder, J.J.; Dijk, van W.; Groot, de W.J.M.

    1996-01-01

    Rye and grass cover crops can potentially intercept residual soil mineral nitrogen (SMN), reduce overwinter leaching, transfer SMN to next growing seasons and reduce the fertilizer need of subsequent crops. These aspects were studied for 6 years in continuous silage maize cv. LG 2080 production

  15. Logging and Agricultural Residue Supply Curves for the Pacific Northwest

    Energy Technology Data Exchange (ETDEWEB)

    Kerstetter, James D.; Lyons, John Kim

    2001-01-01

    This report quantified the volume of logging residues at the county level for current timber harvests. The cost of recovering logging residues was determined for skidding, yearding, loading, chipping and transporting the residues. Supply curves were developed for ten candidate conversion sites in the Pacific Northwest Region. Agricultural field residues were also quantified at the county level using five-year average crop yields. Agronomic constraints were applied to arrive at the volumes available for energy use. Collection costs and transportation costs were determined and supply curves generated for thirteen candidate conversion sites.

  16. The fate of urea applied to tropical bean (Phaseolus vulgaris, L.) crops

    International Nuclear Information System (INIS)

    Cervellini, A.; Libardi, P.L.; Victoria, R.L.; Reichardt, K.

    The fate of nitrogen is studied when it is applied to three bean (Phaseolus vulgaris, L.) crops variety 'carioca' grown on a site of 'Terra Roxa Estruturada' (Paleudalf) soil. Urea labeled with three different 15 N enrichment percentages was used in order to estimate crop recovery of N (and its utilization efficiency), residual effects of N from one crop to another, distribution of N in the soil profile after cropping and leaching losses of N. The superphosphate and the rockphosphate 'Araxa' were also used. Grain yield was not significantly different between the phosphorus treatments, indicating that both P sources behaved similarly. Differences in fertilizer 15 N enrichment did not affect calculated amounts of nitrogen derived from fertilizer and N utilization efficiency (NUE), as expected. The first crop recovered on the average 31,2% of the N from the applied urea. The second crop recovered 6,2% N from the fertilizer applied to the first crop. The third crop recovered only 1,4%. Taking in account the NUE for the three crops, they recovered 44,1% of the N applied to the first crop. The partition of nitrogen applied to the first crop in four components (crop N removal; soil mineral N (NO 3 + NH 4 ); soil organic N and leaching N) is analysed. Due to the low N utilization efficiency of the crop, much of N remains in the soil profile, being potentially available for leaching and so contributing for fertilizer pollution of ground water. (M.A.) [pt

  17. Tradeoffs around crop residue biomass in smallholder crop-livestock systems - What's next?

    NARCIS (Netherlands)

    Tittonell, P.A.; Gérard, B.; Erenstein, O.

    2015-01-01

    Much has been written on the tradeoffs that smallholder farmers face when having to allocate their biomass resources among competing objectives such as feed, fuel, mulch, compost or the market. This paper summarises yet a new body of evidence from 10 studies on tradeoffs in the allocation of cereal

  18. Bioactive Components in Moringa Oleifera Leaves Protect against Chronic Disease

    Science.gov (United States)

    Vergara-Jimenez, Marcela; Almatrafi, Manal Mused

    2017-01-01

    Moringa Oleifera (MO), a plant from the family Moringacea is a major crop in Asia and Africa. MO has been studied for its health properties, attributed to the numerous bioactive components, including vitamins, phenolic acids, flavonoids, isothiocyanates, tannins and saponins, which are present in significant amounts in various components of the plant. Moringa Oleifera leaves are the most widely studied and they have shown to be beneficial in several chronic conditions, including hypercholesterolemia, high blood pressure, diabetes, insulin resistance, non-alcoholic liver disease, cancer and overall inflammation. In this review, we present information on the beneficial results that have been reported on the prevention and alleviation of these chronic conditions in various animal models and in cell studies. The existing limited information on human studies and Moringa Oleifera leaves is also presented. Overall, it has been well documented that Moringa Oleifera leaves are a good strategic for various conditions associated with heart disease, diabetes, cancer and fatty liver. PMID:29144438

  19. Bioactive Components in Moringa Oleifera Leaves Protect against Chronic Disease

    Directory of Open Access Journals (Sweden)

    Marcela Vergara-Jimenez

    2017-11-01

    Full Text Available Moringa Oleifera (MO, a plant from the family Moringacea is a major crop in Asia and Africa. MO has been studied for its health properties, attributed to the numerous bioactive components, including vitamins, phenolic acids, flavonoids, isothiocyanates, tannins and saponins, which are present in significant amounts in various components of the plant. Moringa Oleifera leaves are the most widely studied and they have shown to be beneficial in several chronic conditions, including hypercholesterolemia, high blood pressure, diabetes, insulin resistance, non-alcoholic liver disease, cancer and overall inflammation. In this review, we present information on the beneficial results that have been reported on the prevention and alleviation of these chronic conditions in various animal models and in cell studies. The existing limited information on human studies and Moringa Oleifera leaves is also presented. Overall, it has been well documented that Moringa Oleifera leaves are a good strategic for various conditions associated with heart disease, diabetes, cancer and fatty liver.

  20. Bioactive Components in Moringa Oleifera Leaves Protect against Chronic Disease.

    Science.gov (United States)

    Vergara-Jimenez, Marcela; Almatrafi, Manal Mused; Fernandez, Maria Luz

    2017-11-16

    Moringa Oleifera ( MO ), a plant from the family Moringacea is a major crop in Asia and Africa. MO has been studied for its health properties, attributed to the numerous bioactive components, including vitamins, phenolic acids, flavonoids, isothiocyanates, tannins and saponins, which are present in significant amounts in various components of the plant. Moringa Oleifera leaves are the most widely studied and they have shown to be beneficial in several chronic conditions, including hypercholesterolemia, high blood pressure, diabetes, insulin resistance, non-alcoholic liver disease, cancer and overall inflammation. In this review, we present information on the beneficial results that have been reported on the prevention and alleviation of these chronic conditions in various animal models and in cell studies. The existing limited information on human studies and Moringa Oleifera leaves is also presented. Overall, it has been well documented that Moringa Oleifera leaves are a good strategic for various conditions associated with heart disease, diabetes, cancer and fatty liver.

  1. Paid Family Leave, Fathers' Leave-Taking, and Leave-Sharing in Dual-Earner Households

    OpenAIRE

    Bartel, Ann P.; Rossin-Slater, Maya; Ruhm, Christopher J.; Stearns, Jenna; Waldfogel, Jane

    2015-01-01

    This paper provides quasi-experimental evidence on the impact of paid leave legislation on fathers' leave-taking, as well as on the division of leave between mothers and fathers in dual-earner households. Using difference-in-difference and difference-in-difference-in-difference designs, we study California's Paid Family Leave (CA-PFL) program, which is the first source of government-provided paid parental leave available to fathers in the United States. Our results show that fathers in Califo...

  2. Influência do tipo e da quantidade de resíduos vegetais na eficácia de herbicidas aplicados em pré-emergência na cultura da soja Influence of the type and amount of crop residues in efficiency of herbicides applied pre-emergence in soybean

    Directory of Open Access Journals (Sweden)

    Núbia Maria Correia

    2007-01-01

    Full Text Available Com o objetivo de avaliar, em condições de campo e na região originalmente sob cerrado, os efeitos de resíduos vegetais [sorgo de cobertura (híbrido Cober Exp, milheto forrageiro (var. BN2, capim-pé-de-galinha (Eleusine coracana e capim-braquiária (Brachiaria brizantha] e duas quantidades de palha (3,0 e 5,5 t ha-1, no primeiro ano do estudo, e 3,5 e 5,8 t ha-1, no segundo na eficácia de herbicidas residuais (diclosulam e imazaquin aplicados em pré-emergência na cultura da soja, foi desenvolvido experimento, no ano agrícola 2003/2004 e repetido em 2004/2005, na fazenda Três Marcos, em Uberlândia (MG. Os herbicidas diclosulam e imazaquin não tiveram a eficácia afetada pela presença de palha na superfície do solo, independentemente da quantidade. Associados às coberturas, obteve-se melhor controle. No primeiro ano, após a instalação da cultura da soja, plantas de Eleusine coracana tornaram-se as principais infestantes na parcela de capim-pé-de-galinha.This work was conducted in the agricultural years 2003/04 and 2004/05, at the farm 'Três Marcos', Uberlândia, MG - Brazil to evaluate the effect of crop residues [coverage sorghum (hybrid Cober Exp, forage millet (var. BN2, finger millet (Eleusine coracana and St. Lucia Grass (Brachiaria brizantha] and two amounts of straw (3.0 and 5.5 t ha-1 in the first year and 3.5 and 5.8 t ha-1, in the second year in efficiency of herbicides (diclosulam and uimazaquin applied pre-emergence in soybean, 'Cerrado' conditions. The efficiency of herbicides diclosulam and imazaquin was not affected by the straw at any amount. Associated to the straw coverage, it had best weed control. In the first year, after the soybean field was installed, Eleusine coracana became the major weed species in the finger millet plot.

  3. Residual and Destroyed Accessible Information after Measurements

    Science.gov (United States)

    Han, Rui; Leuchs, Gerd; Grassl, Markus

    2018-04-01

    When quantum states are used to send classical information, the receiver performs a measurement on the signal states. The amount of information extracted is often not optimal due to the receiver's measurement scheme and experimental apparatus. For quantum nondemolition measurements, there is potentially some residual information in the postmeasurement state, while part of the information has been extracted and the rest is destroyed. Here, we propose a framework to characterize a quantum measurement by how much information it extracts and destroys, and how much information it leaves in the residual postmeasurement state. The concept is illustrated for several receivers discriminating coherent states.

  4. Paid Family Leave, Fathers' Leave-Taking, and Leave-Sharing in Dual-Earner Households.

    Science.gov (United States)

    Bartel, Anne P; Rossin-Slater, Maya; Ruhm, Christopher J; Stearns, Jenna; Waldfogel, Jane

    Using difference-in-difference and difference-in-difference-in-difference designs, we study California's Paid Family Leave (CA-PFL) program, the first source of government-provided paid parental leave available to fathers in the Unites States. Relative to the pre-treatment mean, fathers of infants in California are 46 percent more likely to be on leave when CA-PFL is available. In households where both parents work, we find suggestive evidence that CA-PFL increases both father-only leave-taking (i.e., father on leave while mother is at work) and joint leave-taking (i.e., both parents on leave at the same time). Effects are larger for fathers of first-born children than for fathers of later-born children.

  5. Damage of crops by environmental air pollution in Yokkaichi area

    Energy Technology Data Exchange (ETDEWEB)

    Taniyama, T; Sawanaka, K

    1972-01-01

    Crop damage from sulfur dioxide was evaluated in the Yokkaichi area in 1971 by measuring dry matter and seed production. The average concentration of SO/sub 2/ per hour was 0.034 ppM from April to November 1971. There were, however, some cases of monthly hourly averages greater than 0.4 ppM. In these situations damages to major crops was largely due to sulfurous and sulfuric acid mists. The damages to major crops included brown and red spots, apical and peripheral chlorosis, yellowing of leaves, belt-like yellowing of sheath, white or black discoloration of rice plants, nonfertilization of rice plants, apical blight and chlorosis of Welsh onion, partial yellowing and general withering of pine trees in summer (and some death), watering and chlorosis of leaves of brassica species, and yellowing and spot formation on Japanese radishes. Also noted was a decrease in tiller number of rice plants (17.4 in polluted vs. 19.4 in unpolluted areas). Some cases were found in which the sulfur content of SO/sub 2/-damaged crops was higher than that of undamaged crops.

  6. Nitrogen immobilization and mineralization during initial decomposition of 15N-labelled pea and barley residues

    DEFF Research Database (Denmark)

    Jensen, E.S.

    1997-01-01

    The immobilization and mineralization of N following plant residue incorporation were studied in a sandy loam soil using N-15-labelled field pea (Pisum sativum L.) and spring barley (Hordeum vulgare L.) straw. Both crop residues caused a net immobilization of soil-derived inorganic N during...... the complete incubation period of 84 days. The maximum rate of N immobilization was found to 12 and 18 mg soil-derived N g(-1) added C after incorporation of pea and barley residues, respectively. After 7 days of incubation, 21% of the pea and 17% of the barley residue N were assimilated by the soil microbial...... the decomposition of the barley residue. The net mineralization of residue-derived N was 2% in the barley and 22% in the pea residue treatment after 84 days of incubation. The results demonstrated that even if crop residues have a relative low C/N ratio (15), transient immobilization of soil N in the microbial...

  7. Influx of CO2 from Soil Incubated Organic Residues at Constant Temperature

    Directory of Open Access Journals (Sweden)

    Shoukat Ali Abro

    2016-06-01

    Full Text Available Temperature induced CO2 from genotypic residue substances is still less understood. Two types of organic residues (wheat- maize were incubated at a constant temperature (25°C to determine the rate and cumulative influx of CO2 in laboratory experiment for 40 days. Further, the effect of surface and incorporated crop residues with and without phosphorus addition was also studied. Results revealed that mixing of crop residues increased CO2-C evolution significantly & emission rare was 37% higher than that of control. At constant temperature, soil mixed residues, had higher emission rates CO2-C than the residues superimposed. There was linear correlation of CO2-C influxed for phosphorus levels and residue application ways with entire incubation at constant temperature. The mixing of organic residues to soil enhanced SOC levels and biomass of microbially bound N; however to little degree ammonium (NH4-N and nitrate NO3-N nitrogen were decreased.

  8. Effect of the spray volume adjustment model on the efficiency of fungicides and residues in processing tomato

    Energy Technology Data Exchange (ETDEWEB)

    Ratajkiewicz, H.; Kierzek, R.; Raczkowski, M.; Hołodyńska-Kulas, A.; Łacka, A.; Wójtowicz, A.; Wachowiak, M.

    2016-11-01

    This study compared the effects of a proportionate spray volume (PSV) adjustment model and a fixed model (300 L/ha) on the infestation of processing tomato with potato late blight (Phytophthora infestans (Mont.) de Bary) (PLB) and azoxystrobin and chlorothalonil residues in fruits in three consecutive seasons. The fungicides were applied in alternating system with or without two spreader adjuvants. The proportionate spray volume adjustment model was based on the number of leaves on plants and spray volume index. The modified Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method was optimized and validated for extraction of azoxystrobin and chlorothalonil residue. Gas chromatography with a nitrogen and phosphorus detector and an electron capture detector were used for the analysis of fungicides. The results showed that higher fungicidal residues were connected with lower infestation of tomato with PLB. PSV adjustment model resulted in lower infestation of tomato than the fixed model (300 L/ha) when fungicides were applied at half the dose without adjuvants. Higher expected spray interception into the tomato canopy with the PSV system was recognized as the reasons of better control of PLB. The spreader adjuvants did not have positive effect on the biological efficacy of spray volume application systems. The results suggest that PSV adjustment model can be used to determine the spray volume for fungicide application for processing tomato crop. (Author)

  9. Effect of the spray volume adjustment model on the efficiency of fungicides and residues in processing tomato

    Directory of Open Access Journals (Sweden)

    Henryk Ratajkiewicz

    2016-08-01

    Full Text Available This study compared the effects of a proportionate spray volume (PSV adjustment model and a fixed model (300 L/ha on the infestation of processing tomato with potato late blight (Phytophthora infestans (Mont. de Bary (PLB and azoxystrobin and chlorothalonil residues in fruits in three consecutive seasons. The fungicides were applied in alternating system with or without two spreader adjuvants. The proportionate spray volume adjustment model was based on the number of leaves on plants and spray volume index. The modified Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS method was optimized and validated for extraction of azoxystrobin and chlorothalonil residue. Gas chromatography with a nitrogen and phosphorus detector and an electron capture detector were used for the analysis of fungicides. The results showed that higher fungicidal residues were connected with lower infestation of tomato with PLB. PSV adjustment model resulted in lower infestation of tomato than the fixed model (300 L/ha when fungicides were applied at half the dose without adjuvants. Higher expected spray interception into the tomato canopy with the PSV system was recognized as the reasons of better control of PLB. The spreader adjuvants did not have positive effect on the biological efficacy of spray volume application systems. The results suggest that PSV adjustment model can be used to determine the spray volume for fungicide application for processing tomato crop.

  10. Plant biotechnology: transgenic crops.

    Science.gov (United States)

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

    2008-01-01

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

  11. [Diagnosis of nitrogen content in upper and lower corn leaves based on hyperspectral data].

    Science.gov (United States)

    Jin, Liang; Hu, Ke-Lin; Tian, Ming-Ming; Wei, Dan; Li, Hong; Bai, You-Lu; Zhang, Jun-Zheng

    2013-04-01

    Based on the spectral characters of corn leaf nitrogen content in the space, the spectral models for rapid estimating crop nitrogen content were set up, which is practically meaningful to effectively providing the guidance in fertilization. Spectral technology was applied to explore corn leaves nitrogen content distribution regularity and the relationship between the nitrogen content and plant index was analysed and then the estimation models were built. The results showed N content in upper leaves is higher than that in lower leaves in four growing stages; lower leaves at tassel emerge stage are sensitive to nitrogen losses, which could be used in guiding fertilization in grain production; optimum estimation models were built atjointing stage, the full-grown stage and tasseling stage, The research results provided the proof of crop nutrient analysis and rational fertilization.

  12. Pulping and papermaking properties of the leaf fiber and fibrous residue from Agave tequilana

    Energy Technology Data Exchange (ETDEWEB)

    Kurita, T.; Mitsuhashi, S.; Kanetsuna, H.; Iguchi, M.; Shirota, T.; Trujillo, J.J.; Herrera, T.

    1981-01-01

    The leaves and fibrous residue of A. tequilana had fibriles with parallel orientation and helical arrangement to the fiber axis and contained fibers in average length and width of 1.7 mm and 10.3 mu m and 0.8 mm and 25.5 mu m, respectively. The cell wall in leaves was thicker and narrower than those in fibrous residue, and leaves contained cellulose and lignin lower than fibrous residue did. Alkali sulfite cooking of leaves gave pulp, the yield of which was lower than that from fibrous residue. The H/sub 2/On retention and bulk density of leaf pulps increased rapidly on beating suggesting that an internal fibrillation in pulp occurs easily during beating. The breaking length and burst and tear factors of paper from leaf pulp were higher than those from fibrous residue.

  13. SISTEMAS DE MANEJO E EFEITO RESIDUAL DO POTÁSSIO NA PRODUTIVIDADE E NUTRIÇÃO DO FEIJÃO-CAUPI

    Directory of Open Access Journals (Sweden)

    JESSIVALDO RODRIGUES GALVÃO

    2013-01-01

    Full Text Available Cowpea [Vigna unguiculata (L Walp] have great social and economic importance for the Para State. It grows well in areas with low precipitation and two crop cycles can be obtained annually. This study aimed to assess the effect of the residual fertilization from a previous culture (Sorghum bicolor L. Moench and crop systems on cowpea yield and macronutrient concentration on leaves of three cowpea cultivars (BRS- Milênio, BRS-Urubuquara e BRS-Guariba. The study was conducted at the UFRA. The treatments were two crop systems (minimum tillage and conventional, four levels of potassium (50, 100, 200 e 300 kg de KCl ha-1 applied to a previous sorghum culture and the three cowpea cultivars. Treatments were organized as a three (4 x 2 x 3 factor experiment on a randomized complete block design. The soil was a yellow latosol. In each ex- periment plot five plants were selected to determine shoot dry matter and foliar nutrient concentration. Grain yield was determined after harvesting all plants on the experiment plot. The residual KCl fertilization affected foliar nutrient content, but did not affect shoot dry mass or yield of grain. Yield was higher in the minimum tillage system. Highest yield (1590 kg ha-1 was recorded int the cv. ‘Guariba’ when 100 kg of KCl ha-1 had been used in the previous crop. The highest content of leaf N and K was found in cowpea under minimum till- age system. The amount of P and Mg were higher in the conventional system whereas the amount of Ca did not change.

  14. Cover crops support ecological intensification of arable cropping systems

    Science.gov (United States)

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

    2017-02-01

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

  15. [Precautionary maternity leave in Tirol].

    Science.gov (United States)

    Ludescher, K; Baumgartner, E; Roner, A; Brezinka, C

    1998-01-01

    Under Austrian law, precautionary maternity leave is a decree issued by the district public health physician. It forbids a pregnant woman to work and mandates immediate maternity leave. Regular maternity leave for all women employed in all jobs begins at 32 weeks of gestation. Women who work in workplaces deemed dangerous and women with a history of obstetric problems such as premature or growth-retarded babies from previous pregnancies are regularly 'sent' into precautionary maternity leave. The public health physicians of Tirol's nine administrative districts were interviewed and supplied data on precautionary maternity leave from their districts. In 100 women who attended the clinic for pregnancies at risk of the Obstetrics/Gynecology Department of Innsbruck University Hospital and who had already obtained precautionary maternity leave, the medical/administrative procedure was studied in each case and correlated with pregnancy outcome. The town district of Innsbruck and the district that comprises the suburbs of the provincial capital had the highest rates of precautionary maternity leave. The town district of Innsbruck had a rate of 24.3% of all pregnant women (employed and not employed) in precautionary maternity leave in 1997, whereas the whole province of Tirol had 13.4%. More than 80% of decrees for precautionary maternity leave are issued by district public health physicians on the basis of written recommendations from gynecologists. One third of women who are sent into precautionary maternity leave are issued the decree prior to 12 weeks of gestation - mostly cases of multiple pregnancies and women with previous miscarriages. The present system of precautionary maternity leave appears to work in the sense that most working pregnant women with risk factors are correctly identified - with most errors on the side of caution. As the system also helps employers - the employee's pay is paid from the federal family support fund and state insurance once she is in

  16. An operational fluorescence system for crop assessment

    Science.gov (United States)

    Belzile, Charles; Belanger, Marie-Christine; Viau, Alain A.; Chamberland, Martin; Roy, Simon

    2004-03-01

    The development of precision farming requires new tools for plant nutritional stress monitoring. An operational fluorescence system has been designed for vegetation status mapping and stress detection at plant and field scale. The instrument gives relative values of fluorescence at different wavelengths induced by the two-excitation sources. Lightinduced fluorescence has demonstrated successful crop health monitoring and plant nutritional stress detection capabilities. The spectral response of the plants has first been measured with an hyperspectral imager using laser-induced fluorescence. A tabletop imaging fluorometer based on flash lamp technology has also been designed to study the spatial distribution of fluorescence on plant leaves. For field based non-imaging system, LED technology is used as light source to induce fluorescence of the plant. The operational fluorescence system is based on ultraviolet and blue LED to induce fluorescence. Four narrow fluorescence bands centered on 440, 520, 690 and 740nm are detected. The instrument design includes a modular approach for light source and detector. It can accommodate as many as four different light sources and six bands of fluorescence detection. As part of the design for field application, the instrument is compatible with a mobile platform equipped with a GPS and data acquisition system. The current system developed by Telops/GAAP is configured for potato crops fluorescence measurement but can easily be adapted for other crops. This new instrument offers an effective and affordable solution for precision farming.

  17. Soybean growth and yield under cover crops

    Directory of Open Access Journals (Sweden)

    Priscila de Oliveira

    2013-04-01

    Full Text Available The use of cover crops in no-tillage systems can provide better conditions for the development of soybean plants with positive effects on grain yield and growth analysis techniques allow researchers to characterize and understand the behavior of soybean plants under different straw covers. Thus, the aim of this study was to characterize, using growth analysis, yield components and agronomic performance of soybean under common bean, Brachiaria brizantha and pearl millet straws. The experiment was performed on a soil under cerrado in the municipality of Santo Antônio de Goiás, GO. The experiment was arranged in a randomized complete block design with three treatments (cover crops and five replications. Soybean grain yield was lower in the B. brizantha straw treatment (3,708 kg ha-1 than both in the pearl millet (4.772 kg ha-1 and common bean straw treatments (5,200 kg ha-1. The soybean growth analysis in B. brizantha, pearl millet and common bean allowed characterizing the variation in the production of dry matter of leaves, stems, pods and total and leaf area index that provided different grain yields. The cover crop directly affects the soybean grain yield.

  18. European energy crops overview. Country report for Denmark

    Energy Technology Data Exchange (ETDEWEB)

    Statens Planteavlsforsoeg, Tjele Denmark; Statens Jordbrugstekniske Forsoeg, Horsens Denmark

    1996-06-01

    Biomass constitutes a significant contribution to the Danish energy production and is a major tool in increasing the contribution from renewables. So far the focus has been on utilizing existing biomass residues like straw and forest residues and not energy crops. The government has agreed to carry out a demonstration and development programme on energy crops in order to analyse aspects of economy, energy, environment, nature conservancy and comerciality. Several plant species have been investigated for their potential as energy crops and overview information in presented on buchina, sunflower, knotweed, Jerusalem artichoke, false flax, reed Canary grass and corn cockle. More detailed descriptions are given on willow, Miscanthus, energy grain (grain whole crop) and rape which have been most intensively investigated. Rape has been the energy crop grown on the largest scale (40-50,000 ha) but the oil has not been used for energy purposes in Denmark. A research programme on the development of a low input production system for non-food rape is currently conducted. The perennial crops willow and Miscanthus are grown with low input of fertilizer and pesticides and are considered environmentally friendly. Willow-SRC is used as fuel at district heating plants, both commercially and for feasibility studies. Full-scale tests have been carried out on Miscanthus combustion in farm heating plant constructed for straw firing, and on co-combustion with coal at power stations. Grain whole crop (energy grain) has been combusted at a district heating plant, a CHP-plant and a power station. Co-combustion with coal was carried out at a CFB-boiler. Concerning ethanol based on energy crops, only a few activities are in progress. (EG) 89 refs.

  19. Sustainable Agriculture: Cover Cropping

    Science.gov (United States)

    Webster, Megan

    2018-01-01

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

  20. Transpiration and crop yields

    NARCIS (Netherlands)

    Wit, de C.T.

    1958-01-01

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

  1. Biotechnology Towards Energy Crops.

    Science.gov (United States)

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

    2016-03-01

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

  2. Future-proof crops

    NARCIS (Netherlands)

    Kissoudis, Christos; Wiel, van de Clemens; Visser, R.G.F.; Linden, van der Gerard

    2016-01-01

    Breeding for stress-resilient crops strongly depends on technological and biological advancements that have provided a wealth of information on genetic variants and their contribution to stress tolerance. In the context of the upcoming challenges for agriculture due to climate change, such as

  3. Mycorrhiza and crop production

    Energy Technology Data Exchange (ETDEWEB)

    Hayman, D S

    1980-10-09

    This article describes recent research with vesicular-arbuscular mycorrhiza, a symbiotic fungus-root association. The suggestion that the symbiotic association may be harnessed to achieve more economical use of phosphate fertilizers is discussed and the results from various test crops are given.

  4. Parental Leave Policies and Parents' Employment and Leave-Taking

    Science.gov (United States)

    Han, Wen-Jui; Ruhm, Christopher; Waldfogel, Jane

    2009-01-01

    We describe trends in maternal employment and leave-taking after birth of a newborn and analyze the extent to which these behaviors are influenced by parental leave policies. Data are from the June Current Population Survey (CPS) Fertility Supplements, merged with other months of the CPS, and cover the period 1987 to 1994. This time span is one…

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

    Science.gov (United States)

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

    2016-04-01

    Introduction of improved farming practices are important to address the challenges of agricultural production, food security, climate change and resource use efficiency. The integration of livestock with crops provides many benefits including: (1) resource conservation, (2) ecosystem services, (3) soil quality improvements, and (4) risk reduction through diversification of enterprises. Integrated crop livestock systems (ICLS) with the combination of no-tillage and pastures are useful practices to enhance soil organic carbon (SOC) compared with continuous cropping systems (CCS). In this study, the SOC and its fractions in two cropping systems namely (1) ICLS, and (2) CCS were evaluated in Southern Santa Fe Province in Argentina, and the use of delta carbon-13 technique and soil physical fractionation were evaluated to identify sources of SOC in these systems. Two farms inside the same soil cartographic unit and landscape position in the region were compared. The ICLS farm produces lucerne (Medicago sativa Merrill) and oat (Avena sativa L.) grazed by cattle alternatively with grain summer crops sequence of soybean (Glicine max L.) and corn (Zea mays L.), and the farm under continuous cropping system (CCS) produces soybean and corn in a continuous sequence. The soil in the area is predominantly a Typic Hapludoll. Soil samples from 0-5 and 0-20 cm depths (n=4) after the harvest of grain crops were collected in each system and analyzed for total organic carbon (SOC, 0-2000 μm), particulate organic carbon (POC, 50-100 μm) and mineral organic carbon (MOC, is probably due to the presence of deep roots under pastures in ICLS. Delta carbon-13 values for 0-5 cm were -22.9, -21.2 and -19.9 per mil for REF, ICLS and CCS, respectively (Pis explained by the presence of tree species with high lignin content in natural vegetation. Lignin has lower delta carbon-13 compared to cellulose (dominating in crops and pastures), which is present in greater proportion in plant residues of

  6. Production of ethanol, fat and oil and methane gas from several crops. Sushu sakumotsu nado no energygen toshite no hyoka

    Energy Technology Data Exchange (ETDEWEB)

    Uehara, Tsuyoshi; Suganuma, Hirotoshi

    1988-05-01

    Aiming at production of ethanol, fat and oil and so on, ten kinds of miscellaneous cereal crops such as pearl-millet, soybean and so on were grown, and comparative investigation of the production rate which was considered utilization of whole plants were carried out. The suitability of vegetable wastes as methane fermentation materials for the methane gas production was investigated by the constituent analyses and methane fermentation experiments. Nine kinds of the grasses and vegetable wastes such as tomatoe buds, broccoli leaves were used for the investigation. As the results, the estimated yield of ethanol per 10 are from pearl-millet was 690 liter, the estimated yield of fat and oil per 10 are was 70 liter from soybean, The results of the analyses of nine kinds of the farm residues were as follows: (1) carbon content of about 40 %, (2) C/N ratio of 13 av., (3) C/P ratio of 91 av., and (4) the content of C,N and P was roughly appropriate. 680 to 760 milliliter of methane gas was produced from one gram of the dry matter of tomatoe bods, and in case of broccoli leaves, 424 milliliter of methane gas was produced, it was found that these values were not inferior to animal dung. (4 figs, 15 tabs, 6 refs)

  7. Availability of residual nitrogen from fertilizers in soil

    International Nuclear Information System (INIS)

    Jakovljevic, M.; Filipovic, R.; Petrovic, M.

    1983-01-01

    The plant availability of residual fertilizer nitrogen for the next crop was studied in chernozem and pseudogley soils. Release of nitrogen was examined after incubation at 3 and 30 0 C. It was found that the use of increased doses of nitrogen fertilizer (ammonium nitrate) led to an increased release of residual fertilizer nitrogen into plant available forms. The release of this nitrogen fraction was 5-10 times faster in comparison with the remaining soil nitrogen. (author)

  8. Availability of residual nitrogen from fertilizers in soil

    Energy Technology Data Exchange (ETDEWEB)

    Jakovljevic, M.; Filipovic, R.; Petrovic, M. (Institut za Primeni Nuklearne Energije u Poljoprivedri, Veterinarstvu i Sumarstvu, Zemun (Yugoslavia))

    1983-05-01

    The plant availability of residual fertilizer nitrogen for the next crop was studied in chernozem and pseudogley soils. Release of nitrogen was examined after incubation at 3 and 30/sup 0/C. It was found that the use of increased doses of nitrogen fertilizer (ammonium nitrate) led to an increased release of residual fertilizer nitrogen into plant available forms. The release of this nitrogen fraction was 5-10 times faster in comparison with the remaining soil nitrogen.

  9. Building crop models within different crop modelling frameworks

    NARCIS (Netherlands)

    Adam, M.Y.O.; Corbeels, M.; Leffelaar, P.A.; Keulen, van H.; Wery, J.; Ewert, F.

    2012-01-01

    Modular frameworks for crop modelling have evolved through simultaneous progress in crop science and software development but differences among these frameworks exist which are not well understood, resulting in potential misuse for crop modelling. In this paper we review differences and similarities

  10. Crop and varietal diversification of rainfed rice based cropping systems for higher productivity and profitability in Eastern India.

    Science.gov (United States)

    Lal, B; Gautam, Priyanka; Panda, B B; Raja, R; Singh, Teekam; Tripathi, R; Shahid, M; Nayak, A K

    2017-01-01

    Rice-rice system and rice fallows are no longer productive in Southeast Asia. Crop and varietal diversification of the rice based cropping systems may improve the productivity and profitability of the systems. Diversification is also a viable option to mitigate the risk of climate change. In Eastern India, farmers cultivate rice during rainy season (June-September) and land leftovers fallow after rice harvest in the post-rainy season (November-May) due to lack of sufficient rainfall or irrigation amenities. However, in lowland areas, sufficient residual soil moistures are available in rice fallow in the post-rainy season (November-March), which can be utilized for raising second crops in the region. Implementation of suitable crop/varietal diversification is thus very much vital to achieve this objective. To assess the yield performance of rice varieties under timely and late sown conditions and to evaluate the performance of dry season crops following them, three different duration rice cultivars were transplanted in July and August. In dry season several non-rice crops were sown in rice fallow to constitute a cropping system. The results revealed that tiller occurrence, biomass accumulation, dry matter remobilization, crop growth rate, and ultimately yield were significantly decreased under late transplanting. On an average, around 30% yield reduction obtained under late sowing may be due to low temperature stress and high rainfall at reproductive stages of the crop. Dry season crops following short duration rice cultivars performed better in terms of grain yield. In the dry season, toria was profitable when sown earlier and if sowing was delayed greengram was suitable. Highest system productivity and profitability under timely sown rice may be due to higher dry matter remobilization from source to sink. A significant correlation was observed between biomass production and grain yield. We infer that late transplanting decrease the tiller occurrence and assimilate

  11. Cover crops do not increase C sequestration in production crops: evidence from 12 years of continuous measurements

    Science.gov (United States)

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

    2017-04-01

    The numerous reports on carbon (C) loss from cropland soils have recently raised awareness on the climate change mitigation potential of these ecosystems, and on the necessity to improve C sequestration in these soils. Among the multiple solutions that are proposed, several field measurement and modelling studies reported that growing cover crops over fall and winter time could appear as an efficient solution. However, while the large majority of these studies are based on SOC stock inventories and very few information exists from the CO2 flux dynamics perspective. In the present work, we use the results from long-term (12 years) eddy-covariance measurements performed at the Lonzée Terrestrial Observatory (LTO, candidate ICOS site, Belgium) and focus on six intercrop periods managed with (3) and without (3) cover crops after winter wheat main crops, in order to compare their response to environmental factors and to investigate the impact of cover crops on Net Ecosystem Exchange (NEE). Our results showed that cumulated NEE was not significantly affected by the presence of cover crops. Indeed, while larger CO2 assimilation occurred during cover crop growth, this carbon gain was later lost by larger respiration rates due to larger crop residue amounts brought to the soil. As modelled by a Q10-like relationship, significantly larger R10 values were indeed observed during the three intercrop periods cultivated with cover crops. These CO2 flux-based results therefore tend to moderate the generally acknowledged positive impact of cover crops on net C sequestration by croplands. Our results indicate that the effect of growing cover crops on C sequestration could be less important than announced, at least at certain sites.

  12. REMINDER Saved Leave Scheme (SLS) : Simplified procedure for the transfer of leave to saved leave accounts

    CERN Multimedia

    HR Division

    2001-01-01

    As part of the process of streamlining procedures, the HR and AS Divisions have jointly developed a system whereby annual and compensatory leave will henceforth be automatically transferred1) to saved leave accounts. Under the provisions of the voluntary saved leave scheme (SLS), a maximum total of 10 days'2)Previously, every person taking part in the scheme has been individually issued with a form for the purposes of requesting the transfer of leave to the leave account and the transfer has then had to be done manually by HR Division. To streamline the procedure, unused leave of all those taking part in the saved leave scheme at the closure of the leave-year accounts will henceforth be transferred automatically to the saved leave account on that date. This simplification is in the interest of all parties concerned. This automatic transfer procedure has a number of advantages for participants in the SLS scheme. First, staff members will no longer have to take any administrative steps. Secondly, the new proced...

  13. Crop responses to climatic variation

    DEFF Research Database (Denmark)

    Porter, John R.; Semenov, Mikhail A.

    2005-01-01

    The yield and quality of food crops is central to the well being of humans and is directly affected by climate and weather. Initial studies of climate change on crops focussed on effects of increased carbon dioxide (CO2) level and/or global mean temperature and/or rainfall and nutrition on crop...... production. However, crops can respond nonlinearly to changes in their growing conditions, exhibit threshold responses and are subject to combinations of stress factors that affect their growth, development and yield. Thus, climate variability and changes in the frequency of extreme events are important...... for yield, its stability and quality. In this context, threshold temperatures for crop processes are found not to differ greatly for different crops and are important to define for the major food crops, to assist climate modellers predict the occurrence of crop critical temperatures and their temporal...

  14. Negotiating leave in the workplace

    DEFF Research Database (Denmark)

    Bloksgaard, Lotte

    In Denmark leave entitlement is not only regulated by law but is also part of the various collective agreements established in the respective occupational sectors and at the local workplace level. Consequently, Danish fathers have very different leave entitlements, depending on the sector, branch...

  15. Negotiating leave in the workplace

    DEFF Research Database (Denmark)

    Bloksgaard, Lotte

    2014-01-01

    In Denmark leave entitlement is not only regulated by law but is also part of the various collective agreements established in the respective occupational sectors and at the local workplace level. Consequently, Danish fathers have very different leave entitlements, depending on the sector, branch...

  16. Greenhouse gas emissions from cultivation of energy crops may affect the sustainability of biofuels

    DEFF Research Database (Denmark)

    Carter, Mette Sustmann; Hauggaard-Nielsen, Henrik; Heiske, Stefan

    2011-01-01

    will be lower than indicated by our data. We obtained the greatest net reduction in greenhouse gas emissions by co-production of bioethanol and biogas or by biogas alone produced from either fresh grass-clover or whole crop maize. Here the net reduction corresponded to about 8 tons CO2 per hectare per year...... or incorporation of crop residues. In this study we relate measured field emissions of N2O to the reduction in fossil fuel-derived CO2, which is obtained when energy crops are used for biofuel production. The analysis includes five organically managed crops (viz. maize, rye, rye-vetch, vetch and grass......-clover) and three scenarios for conversion of biomass to biofuel. The scenarios are 1) bioethanol production, 2) biogas production and 3) co-production of bioethanol and biogas, where the energy crops are first used for bioethanol fermentation and subsequently the residues from this process are utilized for biogas...

  17. Feeding livestock food residue and the consequences for the environmental impact of meat

    NARCIS (Netherlands)

    Elferink, E.V.; Nonhebel, S.; Moll, H.C.

    2008-01-01

    The environmental impact of meat is high mainly due to the feed required by livestock in combination with the impacts of cultivating, transporting and processing of feed crops such as tapioca and grains. Like regular feed crops, livestock also feed on residue from the food industry, such as pulp,

  18. 5 CFR 630.1204 - Intermittent leave or reduced leave schedule.

    Science.gov (United States)

    2010-01-01

    ... insurance, health benefits, retirement coverage, and leave accrual). (e) The agency shall determine the... REGULATIONS ABSENCE AND LEAVE Family and Medical Leave § 630.1204 Intermittent leave or reduced leave schedule... reduced leave schedule unless the employee and the agency agree to do so. (b) Leave under § 630.1203(a) (3...

  19. The economics of producing energy crops

    International Nuclear Information System (INIS)

    Shapouri, H.; Duffield, J.

    1993-01-01

    The US agricultural sector has an immense supply of natural resources which can be used to product energy. Production of energy from these resources could stimulate economic growth, improve environmental quality, and enhance energy security. However, producing feedstocks and converting biomass to energy require large amounts of capital, equipment, labor, and processing facilities. This paper looks at the costs and benefits of producing energy crops for fuel conversion. A review of studies and crop data show that the cost of growing and converting various feedstocks with current technology is greater than the cost of producing conventional fuels. Conventional motor fuels have a price advantage over biofuels, but market prices don't always reflect the cost of negative externalities imposed on society. Government decisions to invest in alternative energy sources should be based on research that includes the environmental costs and benefits of energy production. The future of biofuels will depend on the continuation of government research and incentive programs. As new technologies advance, the costs of processing energy crops and residues will fall, making biofuels more competitive in energy markets

  20. Salt resistant crop plants

    KAUST Repository

    Roy, Stuart J.

    2014-04-01

    Soil salinity is a major constraint to agriculture. To improve salinity tolerance of crops, various traits can be incorporated, including ion exclusion, osmotic tolerance and tissue tolerance. We review the roles of a range of genes involved in salt tolerance traits. Different tissues and cells are adapted for specific and often diverse function, so it is important to express the genes in specific cell-types and to pyramid a range of traits. Modern biotechnology (marker- assisted selection or genetic engineering) needs to be increasingly used to introduce the correct combination of genes into elite crop cultivars. Importantly, the effects of introduced genes need to be evaluated in the field to determine their effect on salinity tolerance and yield improvement.

  1. Sun and Shade leaves, SIF, and Photosynthetic Capacity

    Science.gov (United States)

    Berry, J. A.; Badgley, G.

    2016-12-01

    Recent advances in retrieval of solar induced chlorophyll fluorescence (SIF) have opened up new possibilities for remote sensing of canopy physiology and structure. To date most of the emphasis has been placed on SIF as an indicator of stress and photosynthetic capacity. However, it is clear that canopy structure can also have an influence. To this point, simulations of SIF in land surface models tend to under predict observed variation in SIF. Also, large, systematic differences in SIF from different canopy types seem to correlate well with the photosynthetic capacity of these canopies. SIF emissions from pampered crops can be several-fold that from evergreen, needle-leaf forests. Yet, these may have similar vegetation indices and absorb a similar fraction of incident PAR. SIF photons produced in a conifer canopy do have a lower probability of escaping its dense, clumped foliage. However, this does not explain the correlated differences in photosynthetic rate and SIF. It is useful, in this regard, to consider the separate contributions of sun and shade leaves to the SIF emitted by a canopy. Sun leaves tend to be displayed to intercept the direct solar beam, and these highly illuminated leaves are often visible from above the canopy. Sun leaves produce more SIF and a large fraction of it escapes. Therefore, the intensity of SIF may be a sensitive indicator of the partitioning of absorbed PAR to sun and shade leaves. Many models account tor the different photosynthetic capacity of sun and shade leaves in calculating canopy responses. However, the fraction of leaves in each category is usually parameterized by an assumed leaf angle distribution (e.g. spherical). In reality, the sun/shade fraction can vary over a wide range, and it has been difficult to measure. SIF and possibly near-IR reflectance of canopies can be used to specify this key parameter with obvious importance to understanding photosynthetic rate.

  2. Sequential use of the STICS crop model and of the MACRO pesticide fate model to simulate pesticides leaching in cropping systems.

    Science.gov (United States)

    Lammoglia, Sabine-Karen; Moeys, Julien; Barriuso, Enrique; Larsbo, Mats; Marín-Benito, Jesús-María; Justes, Eric; Alletto, Lionel; Ubertosi, Marjorie; Nicolardot, Bernard; Munier-Jolain, Nicolas; Mamy, Laure

    2017-03-01

    The current challenge in sustainable agriculture is to introduce new cropping systems to reduce pesticides use in order to reduce ground and surface water contamination. However, it is difficult to carry out in situ experiments to assess the environmental impacts of pesticide use for all possible combinations of climate, crop, and soils; therefore, in silico tools are necessary. The objective of this work was to assess pesticides leaching in cropping systems coupling the performances of a crop model (STICS) and of a pesticide fate model (MACRO). STICS-MACRO has the advantage of being able to simulate pesticides fate in complex cropping systems and to consider some agricultural practices such as fertilization, mulch, or crop residues management, which cannot be accounted for with MACRO. The performance of STICS-MACRO was tested, without calibration, from measurements done in two French experimental sites with contrasted soil and climate properties. The prediction of water percolation and pesticides concentrations with STICS-MACRO was satisfactory, but it varied with the pedoclimatic context. The performance of STICS-MACRO was shown to be similar or better than that of MACRO. The improvement of the simulation of crop growth allowed better estimate of crop transpiration therefore of water balance. It also allowed better estimate of pesticide interception by the crop which was found to be crucial for the prediction of pesticides concentrations in water. STICS-MACRO is a new promising tool to improve the assessment of the environmental risks of pesticides used in cropping systems.

  3. Cover Crop Biomass Harvest Influences Cotton Nitrogen Utilization and Productivity

    Directory of Open Access Journals (Sweden)

    F. Ducamp

    2012-01-01

    Full Text Available There is a potential in the southeastern US to harvest winter cover crops from cotton (Gossypium hirsutum L. fields for biofuels or animal feed use, but this could impact yields and nitrogen (N fertilizer response. An experiment was established to examine rye (Secale cereale L. residue management (RM and N rates on cotton productivity. Three RM treatments (no winter cover crop (NC, residue removed (REM and residue retained (RET and four N rates for cotton were studied. Cotton population, leaf and plant N concentration, cotton biomass and N uptake at first square, and cotton biomass production between first square and cutout were higher for RET, followed by REM and NC. However, leaf N concentration at early bloom and N concentration in the cotton biomass between first square and cutout were higher for NC, followed by REM and RET. Seed cotton yield response to N interacted with year and RM, but yields were greater with RET followed by REM both years. These results indicate that a rye cover crop can be beneficial for cotton, especially during hot and dry years. Long-term studies would be required to completely understand the effect of rye residue harvest on cotton production under conservation tillage.

  4. Mineral composition and ash content of six major energy crops

    Energy Technology Data Exchange (ETDEWEB)

    Monti, Andrea; Venturi, Gianpietro [Department of Agroenvironmental Science and Technologies (DiSTA), University of Bologna, Viale G. Fanin, 44, 40127 Bologna (Italy); Di Virgilio, Nicola [Institute of Biometeorology, National Research Council, Via P. Gobetti, 101 I, 40129 Bologna (Italy)

    2008-03-15

    The chemical composition of biofuels has not received adequate attention given that it is an important aspect in the introduction of energy crops. In this study, the ash content and mineral composition (C, N, Al, Ca, Cl, Fe, K, Mg, Na, P, S, Si) of stems, leaves and reproductive organs of some promising energy crops were determined and compared with the respective recommended thresholds reported in literature. Overall, cynara exhibited the highest ash and mineral contents, which indicate high slagging, fouling and corrosion tendencies. However, cynara also showed the lowest Si content, both in leaves (4.3 g kg{sup -1}) and in stems (0.9 g kg{sup -1}). Sweet sorghum and giant reed exhibited the highest N content (up to 16 g kg{sup -1}), which greatly exceeded the recommended limits in leaves. Importantly, Cl always exceeded the recommended limits (up to 18 mg kg{sup -1} in cynara), both in stems and in leaves, thus resulting in a major stumbling block for all crops. Several significant correlations among elements were found at a single plant part; conversely these correlations were generally very weak considering different plant components, with the exception of K (r=0.91**), P (r=0.94**) and ashes (r=0.64**). Generally, leaves resulted in a significant deterioration of biofuel quality when compared with stems and flower heads. Therefore, agricultural strategies aimed at reducing the leaf component (e.g. by delaying the harvest) may considerably improve the suitability of biofuels for current combustion plants. (author)

  5. Radiation and crop improvement

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1960-09-15

    The present state of the research was reviewed and its results analyzed at an international scientific Symposium on the Effects of Ionizing Radiations on Seeds and their Significance for Crop Improvement held at Karlsruhe, Federal Republic of Germany, in 1960. The experts began a detailed examination of certain special aspects of the radiobiology of seeds. Some of the topics discussed related to the processes initiated in seeds as a result of irradiation. The influence of environmental factors, such as temperature, humidity and the presence or absence of oxygen, was also evaluated. Variations in the sensitivity to radiation were taken into consideration and ways of modifying the sensitivity were examined. Two sessions were devoted to a study of radiation- and chemically-induced chromosome breakage and reunion. The nature and mechanism of chromosome breakage and reunion area subject of basic importance in all radiobiological studies and naturally constituted one of the main topics of discussion at the Karlsruhe symposium. The symposium discussed the relevance of these basic scientific questions to crop improvement. Whether irradiation itself, without producing any hereditary changes, can stimulate crop yields is a matter of considerable interest. It has been found that in some cases the effect is stimulating, while in others it is inhibitive. A number of experiments were described and an attempt was made to deduce certain principles from the results obtained

  6. Cropping management using color and color infrared aerial photographs

    Science.gov (United States)

    Morgan, K. M.; Morris-Jones, D. R.; Lee, G. B.; Kiefer, R. W.

    1979-01-01

    The Universal Soil Loss Equation (USLE) is a widely accepted tool for erosion prediction and conservation planning. Solving this equation yields the long-term average annual soil loss that can be expected from rill and inter-rill erosion. In this study, manual interpretation of color and color infrared 70 mm photography at the scale of 1:60,000 is used to determine the cropping management factor in the USLE. Accurate information was collected about plowing practices and crop residue cover (unharvested vegetation) for the winter season on agricultural land in Pheasant Branch Creek watershed in Dane County, Wisconsin.

  7. Soil Organic Carbon Response to Cover Crop and Nitrogen Fertilization under Bioenergy Sorghum

    Science.gov (United States)

    Sainju, U. M.; Singh, H. P.; Singh, B. P.

    2015-12-01

    Removal of aboveground biomass for bioenergy/feedstock in bioenergy cropping systems may reduce soil C storage. Cover crop and N fertilization may provide additional crop residue C and sustain soil C storage compared with no cover crop and N fertilization. We evaluated the effect of four winter cover crops (control or no cover crop