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Sample records for soils annual crops

  1. Comparison of soil microbial respiration and carbon turnover under perennial and annual biofuel crops in two agricultural soils

    NASA Astrophysics Data System (ADS)

    Szymanski, L. M.; Marin-Spiotta, E.; Sanford, G. R.; Jackson, R. D.; Heckman, K. A.

    2015-12-01

    Bioenergy crops have the potential to provide a low carbon-intensive alternative to fossil fuels. More than a century of agricultural research has shown that conventional cropping systems can reduce soil organic matter (SOM) reservoirs, which cause long-term soil nutrient loss and C release to the atmosphere. In the face of climate change and other human disruptions to biogeochemical cycles, identifying biofuel crops that can maintain or enhance soil resources is desirable for the sustainable production of bioenergy. The objective of our study was to compare the effects of four biofuel crop treatments on SOM dynamics in two agricultural soils: Mollisols at Arlington Agricultural Research Station in Wisconsin and Alfisols at Kellogg Biological Station in Michigan, USA. We used fresh soils collected in 2013 and archived soils from 2008 to measure the effects of five years of crop management. Using a one-year long laboratory soil incubation coupled with a regression model and radiocarbon measurements, we separated soils into three SOM pools and their corresponding C turnover times. We found that the active pool, or biologically available C, was more sensitive to management and is an earlier indicator of changes to soil C dynamics than bulk soil C measurements. There was no effect of treatment on the active pool size at either site; however, the percent C in the active pool decreased, regardless of crop type, in surface soils with high clay content. At depth, the response of the slow pool differed between annual and perennial cropping systems. The distribution of C among SOM fractions varied between the two soil types, with greater C content associated with the active fraction in the coarser textured-soil and greater C content associated with the slow-cycling fraction in the soils with high clay content. These results suggest that the effects of bioenergy crops on soil resources will vary geographically, with implications for the carbon-cost of biocrop production.

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

    PubMed Central

    Esmaeili Taheri, Ahmad; Bainard, Luke D.; Yang, Chao; Navarro-Borrell, Adriana; Hamel, Chantal

    2014-01-01

    Soil fungi are a critical component of agroecosystems and provide ecological services that impact the production of food and bioproducts. Effective management of fungal resources is essential to optimize the productivity and sustainability of agricultural ecosystems. In this review, we (i) highlight the functional groups of fungi that play key roles in agricultural ecosystems, (ii) examine the influence of agronomic practices on these fungi, and (iii) propose ways to improve the management and contribution of soil fungi to annual cropping systems. Many of these key soil fungal organisms (i.e., arbuscular mycorrhizal fungi and fungal root endophytes) interact directly with plants and are determinants of the efficiency of agroecosystems. In turn, plants largely control rhizosphere fungi through the production of carbon and energy rich compounds and of bioactive phytochemicals, making them a powerful tool for the management of soil fungal diversity in agriculture. The use of crop rotations and selection of optimal plant genotypes can be used to improve soil biodiversity and promote beneficial soil fungi. In addition, other agronomic practices (e.g., no-till, microbial inoculants, and biochemical amendments) can be used to enhance the effect of beneficial fungi and increase the health and productivity of cultivated soils. PMID:25247177

  3. Effect of Potassium on Uptake of 137Cs in Food Crops Grown on Coral Soils: Annual Crops at Bikini Atoll

    SciTech Connect

    Stone, E R; Robinson, W

    2002-02-01

    In 1954 a radioactive plume from the thermonuclear device code named BRAVO contaminated the principal residential islands, Eneu and Bikini, of Bikini Atoll (11{sup o} 36 minutes N; 165{sup o} 22 minutes E), now part of the Republic of the Marshall Islands. The resulting soil radioactivity diminished greatly over the three decades before the studies discussed below began. By that time the shorter-lived isotopes had all but disappeared, but strontium-90 ({sup 90}Sr), and cesium-137, ({sup 137}Cs) were reduced by only one half-life. Minute amounts of the long-lived isotopes, plutonium-239+240 ({sup 239+240}Pu) and americium-241 ({sup 241}Am), were present in soil, but were found to be inconsequential in the food chain of humans and land animals. Rather, extensive studies demonstrated that the major concern for human health was {sup 137}Cs in the terrestrial food chain (Robison et al., 1983; Robison et al., 1997). The following papers document results from several studies between 1986 and 1997 aimed at minimizing the {sup 137}Cs content of annual food crops. The existing literature on radiocesium in soils and plant uptake is largely a consequence of two events: the worldwide fallout of 1952-58, and the fallout from Chernobyl. The resulting studies have, for the most part, dealt either with soils containing some amount of silicate clays and often with appreciable K, or with the short-term development of plants in nutrient cultures.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  5. Inorganic Nutrients Increase Humification Efficiency and C-Sequestration in an Annually Cropped Soil

    PubMed Central

    Richardson, Alan E.; Wade, Len J.; Conyers, Mark; Kirkegaard, John A.

    2016-01-01

    Removing carbon dioxide (CO2) from the atmosphere and storing the carbon (C) in resistant soil organic matter (SOM) is a global priority to restore soil fertility and help mitigate climate change. Although it is widely assumed that retaining rather than removing or burning crop residues will increase SOM levels, many studies have failed to demonstrate this. We hypothesised that the microbial nature of resistant SOM provides a predictable nutrient stoichiometry (C:nitrogen, C:phosphorus and C:sulphur–C:N:P:S) to target using supplementary nutrients when incorporating C-rich crop residues into soil. An improvement in the humification efficiency of the soil microbiome as a whole, and thereby C-sequestration, was predicted. In a field study over 5 years, soil organic-C (SOC) stocks to 1.6 m soil depth were increased by 5.5 t C ha-1 where supplementary nutrients were applied with incorporated crop residues, but were reduced by 3.2 t C ha-1 without nutrient addition, with 2.9 t C ha-1 being lost from the 0–10 cm layer. A net difference of 8.7 t C ha-1 was thus achieved in a cropping soil over a 5 year period, despite the same level of C addition. Despite shallow incorporation (0.15 m), more than 50% of the SOC increase occurred below 0.3 m, and as predicted by the stoichiometry, increases in resistant SOC were accompanied by increases in soil NPS at all depths. Interestingly the C:N, C:P and C:S ratios decreased significantly with depth possibly as a consequence of differences in fungi to bacteria ratio. Our results demonstrate that irrespective of the C-input, it is essential to balance the nutrient stoichiometry of added C to better match that of resistant SOM to increase SOC sequestration. This has implications for global practices and policies aimed at increasing SOC sequestration and specifically highlight the need to consider the hidden cost and availability of associated nutrients in building soil-C. PMID:27144282

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

    PubMed

    Suddick, Emma C; Six, Johan

    2013-11-01

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

  7. Annual cover crops do not inhibit early growth of perennial grasses on a disturbed restoration soil in the Northern Great Plains, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In agricultural, rangeland, and forest system revegetation projects, cover crops are used for competitive exclusion of weeds and to stabilize soil. Within revegetation projects, annual or short-lived perennial grasses are often sown at the same time as the perennial grasses that are the desired spec...

  8. Double-cropping annual ryegrass and bermudagrass to reduce phosphorus levels in soil with history of poultry litter application

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Double-cropping forages may help to ameliorate excess soil nutrients in manure-impacted fields. Studies were conducted on Savannah soil with a 30+ yr history of broiler litter to determine the yield of biomass and P in bermudagrass (summer) and ryegrass-bermudagrass (year-round) forage systems. Duri...

  9. A Centralized Regional Database for Winter Cover Crops in Annual Cropping Systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Winter cover crops have the potential to reduce erosion, minimize losses of nitrogen and phosphorus, and increase soil carbon in annual cropping systems in the Midwest. Public support, however, for incentives to farmers to adopt cover crops is minimal. Therefore, development of location-specific rec...

  10. Effects of dairy manure management in annual and perennial cropping systems on soil microbial communities associated with in situ N2O fluxes

    NASA Astrophysics Data System (ADS)

    Dunfield, Kari; Thompson, Karen; Bent, Elizabeth; Abalos, Diego; Wagner-Riddle, Claudia

    2016-04-01

    Liquid dairy manure (LDM) application and ploughing events may affect soil microbial community functioning differently between perennial and annual cropping systems due to plant-specific characteristics stimulating changes in microbial community structure. Understanding how these microbial communities change in response to varied management, and how these changes relate to in situ N2O fluxes may allow the creation of predictive models for use in the development of best management practices (BMPs) to decrease nitrogen (N) losses through choice of crop, plough, and LDM practices. Our objectives were to contrast changes in the population sizes and community structures of genes associated with nitrifier (amoA, crenamoA) and denitrifier (nirK, nirS, nosZ) communities in differently managed annual and perennial fields demonstrating variation in N2O flux, and to determine if differences in these microbial communities were linked to the observed variation in N2O fluxes. Soil was sampled in 2012 and in 2014 in a 4-ha spring-applied LDM grass-legume (perennial) plot and two 4-ha corn (annual) treatments under fall or spring LDM application. Soil DNA was extracted and used to target N-cycling genes via qPCR (n=6) and for next-generation sequencing (Illumina Miseq) (n=3). Significantly higher field-scale N2O fluxes were observed in the annual plots compared to the perennial system; however N2O fluxes increased after plough down of the perennial plot. Nonmetric multidimensional scaling (NMS) indicated differences in N-cycling communities between annual and perennial cropping systems, and some communities became similar between annual and perennial plots after ploughing. Shifts in these communities demonstrated relationships with agricultural management, which were associated with differences in N2O flux. Indicator species analysis was used to identify operational taxonomic units (OTUs) most responsible for community shifts related to management. Nitrifying and denitrifying soil

  11. Crop Residue and Soil Water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Crop yield is greatly influenced by the amount of water that moves from the soil, through the plant, and out into the atmosphere. Winter wheat yield responds linearly to available soil water content at planting (bu/a = 5.56 + 5.34*inches). Therefore, storing precipitation in the soil during non-crop...

  12. Soil total carbon and crop yield affected by crop rotation and cultural practice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stacked crop rotation and improved cultural practice have been used to control pests, but their impact on soil organic C (SOC) and crop yield are lacking. We evaluated the effects of stacked vs. alternate-year rotations and cultural practices on SOC at the 0- to 125-cm depth and annualized crop yiel...

  13. Chemistry and microbial functional diversity differences in biofuel crop and grassland soils in multiple geographies

    EPA Science Inventory

    As crop and non-crop lands are increasingly converted to biofuel feedstock production, it is of interest to identify potential impacts of annual and perennial feedstocks on soil ecosystem services. Soil samples were obtained from diverse regionally distributed biofuel cropping si...

  14. Soil Fungal Distribution and Functionality as Affected by Grazing and Vegetation Components of Integrated Crop-Livestock Agroecosystems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Integrated crop and livestock (ICL) agroecosystems are characterized by a mixture of perennial or annual vegetation grazed by livestock and annual harvested crops. Compared to annual crops, ICLs hold the potential to enhance soil organic matter (OM) inputs, carbon sequestration, nutrient cycling, an...

  15. Soil water evaporation and crop residues

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  16. Tolerance of Soybean Crops to Soil Waterlogging

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Monoculture of irrigated paddy rice, common in the Mississippi delta of the United States and in Asia, diminishes soil nutrients, compacts soils, contaminates water supplies, and increases pest and diseases. While the addition of soybean crops to this cropping ecosystem can attenuate many of these p...

  17. Perennial crop phase effects on soil fertility

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is a need to develop agricultural management systems that enhance soil fertility and reduce reliance on external inputs. Perennial phases in crop rotations are effective at restoring soil fertility, though little information exists in the northern Great Plains regarding soil-based outcomes re...

  18. Chemistry and microbial functional diversity differences in biofuel crop and grassland soils in multiple geographies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As crop and non-crop lands are increasingly becoming converted to biofuel feedstock production, it is of interest to identify potential impacts of annual and perennial feedstocks on soil ecosystem services. Soil samples obtained from 6 regional sets of switchgrass (Panicum virgatum L.) and 3 regiona...

  19. Dryland soil chemical properties and crop yields affected by long-term tillage and cropping sequence.

    PubMed

    Sainju, Upendra M; Allen, Brett L; Caesar-TonThat, Thecan; Lenssen, Andrew W

    2015-01-01

    Information on the effect of long-term management on soil nutrients and chemical properties is scanty. We examined the 30-year effect of tillage frequency and cropping sequence combination on dryland soil Olsen-P, K, Ca, Mg, Na, SO4-S, and Zn concentrations, pH, electrical conductivity (EC), and cation exchange capacity (CEC) at the 0-120 cm depth and annualized crop yield in the northern Great Plains, USA. Treatments were no-till continuous spring wheat (Triticum aestivum L.) (NTCW), spring till continuous spring wheat (STCW), fall and spring till continuous spring wheat (FSTCW), fall and spring till spring wheat-barley (Hordeum vulgare L., 1984-1999) followed by spring wheat-pea (Pisum sativum L., 2000-2013) (FSTW-B/P), and spring till spring wheat-fallow (STW-F, traditional system). At 0-7.5 cm, P, K, Zn, Na, and CEC were 23-60% were greater, but pH, buffer pH, and Ca were 6-31% lower in NTCW, STCW, and FSTW-B/P than STW-F. At 7.5-15 cm, K was 23-52% greater, but pH, buffer pH, and Mg were 3-21% lower in NTCW, STCW, FSTCW, FSTW-B/P than STW-F. At 60-120 cm, soil chemical properties varied with treatments. Annualized crop yield was 23-30% lower in STW-F than the other treatments. Continuous N fertilization probably reduced soil pH, Ca, and Mg, but greater crop residue returned to the soil increased P, K, Na, Zn, and CEC in NTCW and STCW compared to STW-F. Reduced tillage with continuous cropping may be adopted for maintaining long-term soil fertility and crop yields compared with the traditional system.

  20. Soil carbon changes for bioenergy crops.

    SciTech Connect

    Andress, D.

    2004-04-22

    Bioenergy crops, which displace fossil fuels when used to produce ethanol, biobased products, and/or electricity, have the potential to further reduce atmospheric carbon levels by building up soil carbon levels, especially when planted on lands where these levels have been reduced by intensive tillage. The purpose of this study is to improve the characterization of the soil carbon (C) sequestration for bioenergy crops (switchgrass, poplars, and willows) in the Greenhouse gases, Regulated Emissions, and Energy Use in Transportation (GREET) model (Wang 1999) by using the latest results reported in the literature and by Oak Ridge National Laboratory (ORNL). Because soil carbon sequestration for bioenergy crops can play a significant role in reducing greenhouse gas (GHG) emissions for cellulosic ethanol, it is important to periodically update the estimates of soil carbon sequestration from bioenergy crops as new and better data become available. We used the three-step process described below to conduct our study.

  1. Soil Moisture as an Estimator for Crop Yield in Germany

    NASA Astrophysics Data System (ADS)

    Peichl, Michael; Meyer, Volker; Samaniego, Luis; Thober, Stephan

    2015-04-01

    Annual crop yield depends on various factors such as soil properties, management decisions, and meteorological conditions. Unfavorable weather conditions, e.g. droughts, have the potential to drastically diminish crop yield in rain-fed agriculture. For example, the drought in 2003 caused direct losses of 1.5 billion EUR only in Germany. Predicting crop yields allows to mitigate negative effects of weather extremes which are assumed to occur more often in the future due to climate change. A standard approach in economics is to predict the impact of climate change on agriculture as a function of temperature and precipitation. This approach has been developed further using concepts like growing degree days. Other econometric models use nonlinear functions of heat or vapor pressure deficit. However, none of these approaches uses soil moisture to predict crop yield. We hypothesize that soil moisture is a better indicator to explain stress on plant growth than estimations based on precipitation and temperature. This is the case because the latter variables do not explicitly account for the available water content in the root zone, which is the primary source of water supply for plant growth. In this study, a reduced form panel approach is applied to estimate a multivariate econometric production function for the years 1999 to 2010. Annual crop yield data of various crops on the administrative district level serve as depending variables. The explanatory variable of major interest is the Soil Moisture Index (SMI), which quantifies anomalies in root zone soil moisture. The SMI is computed by the mesoscale Hydrological Model (mHM, www.ufz.de/mhm). The index represents the monthly soil water quantile at a 4 km2 grid resolution covering entire Germany. A reduced model approach is suitable because the SMI is the result of a stochastic weather process and therefore can be considered exogenous. For the ease of interpretation a linear functionality is preferred. Meteorological

  2. Cropping systems and control of soil erosion in a Mediterranean environment

    NASA Astrophysics Data System (ADS)

    Cosentino, Salvatore; Copani, Venera; Testa, Giorgio; Scalici, Giovanni

    2013-04-01

    The research has been carried out over the years 1996-2010 in an area of the internal hill of Sicily region (Enna, c.da Geracello, 550 m a. s. l. 37° 23' N. Lat, 14° 21' E. Long) in the center of Mediterranean Sea, mainly devoted to durum wheat cultivation, using the experimental plots, established in 1996 on a slope of 26-28%, equipped to determine surface runoff and soil losses. The establishment consists of twelve plots, having 40 m length and 8 m width. In order to study the effect of different field crop systems in controlling soil erosion in slopes subjected to water erosion, the following systems were studied: permanent crops, tilled annual crops, no-tilled annual crops, set-aside. The used crops were: durum wheat, faba bean, rapeseed, subterranean clover, Italian ryegrass, alfalfa, sweetvetch, moon trefoil, barley, sweet sorghum, sunflower. The results pointed out that the cropping systems with perennial crops allowed to keep low the soil loss, while annual crop rotation determined a high amount of soil loss. Sod seeding showed promising results also for annual crop rotations.

  3. The interactive effects of soil transplant into colder regions and cropping on soil microbiology and biogeochemistry.

    PubMed

    Liu, Shanshan; Wang, Feng; Xue, Kai; Sun, Bo; Zhang, Yuguang; He, Zhili; Van Nostrand, Joy D; Zhou, Jizhong; Yang, Yunfeng

    2015-03-01

    Soil transplant into warmer regions has been shown to alter soil microbiology. In contrast, little is known about the effects of soil transplant into colder regions, albeit that climate cooling has solicited attention in recent years. To address this question, we transplanted bare fallow soil over large transects from southern China (subtropical climate zone) to central (warm temperate climate zone) and northern China (cold temperate climate zone). After an adaptation period of 4 years, soil nitrogen components, microbial biomass and community structures were altered. However, the effects of soil transplant on microbial communities were dampened by maize cropping, unveiling a negative interaction between cropping and transplant. Further statistical analyses with Canonical correspondence analysis and Mantel tests unveiled annual average temperature, relative humidity, aboveground biomass, soil pH and NH4 (+) -N content as environmental attributes closely correlated with microbial functional structures. In addition, average abundances of amoA-AOA (ammonia-oxidizing archaea) and amoA-AOB (ammonia-oxidizing bacteria) genes were significantly (P < 0.05) correlated with soil nitrification capacity, hence both AOA and AOB contributed to the soil functional process of nitrification. These results suggested that the soil nitrogen cycle was intimately linked with microbial community structure, and both were subjected to disturbance by soil transplant to colder regions and plant cropping.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Development of crop rotations that support sustainable agriculture depends on understanding complex relationships between soils, crops, and yield. Objectives were to measure how soil chemical and physical attributes as well as corn and soybean stover dry weight, stover mineral concentrations, seed ...

  5. Micronutrients in Soils, Crops, and Livestock

    NASA Astrophysics Data System (ADS)

    Gupta, Umesh C.; Wu, Kening; Liang, Siyuan

    Micronutrient concentrations are generally higher in the surface soil and decrease with soil depth. In spite of the high concentration of most micronutrients in soils, only a small fraction is available to plants. Micronutrients, also known as trace elements, are required in microquantities but their lack can cause serious crop production and animal health problems. Crops vary considerably in their response to various micronutrients. Brassicas and legumes are highly responsive to molybdenum (Mo) and boron (B), whereas corn and other cereals are more responsive to zinc (Zn) and copper (Cu). Micronutrient deficiencies are more common in humid temperate regions, as well as in humid tropical regions, because of intense leaching associated with high precipitation. Soil pH is one of the most important factors affecting the availability of micronutrients to plants. With increasing pH, the availability of these nutrients is reduced with the exception of Mo whose availability increases as soil pH increases. In most plant species, leaves contain higher amounts of nutrients than other plant parts. Therefore, whenever possible, leaves should be sampled to characterize the micronutrient status of crops. Deficiency symptoms for most micronutrients appear on the younger leaves at the top of the plant, whereas toxicity symptoms generally appear on the older leaves of plants. As summarized by Deckers and Steinnes, micronutrient deficiencies are widespread in developing countries, which have much poorer soil resources than the fertile soils of Europe and North America. Many of these areas lie in the humid tropics with extremely infertile, highly weathered, and/or highly leached soils, which are intensely deficient in nutrients. The rest of such soils are in the semiarid and areas adjacent to the latter, where alkaline and calcareous soil conditions severely limit the availability of micronutrients to plants. Frequently, the Cu, iron (Fe), manganese (Mn), Zn, and selenium (Se) levels

  6. Soil moisture monitoring for crop management

    NASA Astrophysics Data System (ADS)

    Boyd, Dale

    2015-07-01

    The 'Risk management through soil moisture monitoring' project has demonstrated the capability of current technology to remotely monitor and communicate real time soil moisture data. The project investigated whether capacitance probes would assist making informed pre- and in-crop decisions. Crop potential and cropping inputs are increasingly being subject to greater instability and uncertainty due to seasonal variability. In a targeted survey of those who received regular correspondence from the Department of Primary Industries it was found that i) 50% of the audience found the information generated relevant for them and less than 10% indicted with was not relevant; ii) 85% have improved their knowledge/ability to assess soil moisture compared to prior to the project, with the most used indicator of soil moisture still being rain fall records; and iii) 100% have indicated they will continue to use some form of the technology to monitor soil moisture levels in the future. It is hoped that continued access to this information will assist informed input decisions. This will minimise inputs in low decile years with a low soil moisture base and maximise yield potential in more favourable conditions based on soil moisture and positive seasonal forecasts

  7. Aggregate Carbon Pools after 13 Years of Integrated Crop-Livestock Management in Semiarid Soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Semi-arid regions have the potential to sequester soil organic carbon (SOC) but the magnitude and rate of sequestration is highly management specific. Integrated crop-livestock (ICL) systems that utilize perennial or high-residue no-till annual forage crops as part of the overall agronomic system ma...

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

    NASA Astrophysics Data System (ADS)

    Krümmelbein, Julia

    2013-04-01

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

  9. Soil fertility, crop biodiversity, and farmers' revenues: Evidence from Italy.

    PubMed

    Di Falco, Salvatore; Zoupanidou, Elisavet

    2017-03-01

    This paper analyzes the interplay between soil fertility, crop biodiversity, and farmers' revenues. We use a large, original, farm-level panel dataset. Findings indicate that both crop biodiversity and soil fertility have positive effects on farmers' revenues. It is also shown that crop biodiversity and soil fertility may act as substitutes. These results provide evidence for the important role of diversity in the resilience of agroecosystems. Crop diversification can be a potential strategy to support productivity when soils are less fertile.

  10. Impacts of crop growth dynamics on soil quality at the regional scale

    NASA Astrophysics Data System (ADS)

    Gobin, Anne

    2014-05-01

    Agricultural land use and in particular crop growth dynamics can greatly affect soil quality. Both the amount of soil lost from erosion by water and soil organic matter are key indicators for soil quality. The aim was to develop a modelling framework for quantifying the impacts of crop growth dynamics on soil quality at the regional scale with test case Flanders. A framework for modelling the impacts of crop growth on soil erosion and soil organic matter was developed by coupling the dynamic crop cover model REGCROP (Gobin, 2010) to the PESERA soil erosion model (Kirkby et al., 2009) and to the RothC carbon model (Coleman and Jenkinson, 1999). All three models are process-based, spatially distributed and intended as a regional diagnostic tool. A geo-database was constructed covering 10 years of crop rotation in Flanders using the IACS parcel registration (Integrated Administration and Control System). Crop allometric models were developed from variety trials to calculate crop residues for common crops in Flanders and subsequently derive stable organic matter fluxes to the soil. Results indicate that crop growth dynamics and crop rotations influence soil quality for a very large percentage. soil erosion mainly occurs in the southern part of Flanders, where silty to loamy soils and a hilly topography are responsible for soil loss rates of up to 40 t/ha. Parcels under maize, sugar beet and potatoes are most vulnerable to soil erosion. Crop residues of grain maize and winter wheat followed by catch crops contribute most to the total carbon sequestered in agricultural soils. For the same rotations carbon sequestration is highest on clay soils and lowest on sandy soils. This implies that agricultural policies that impact on agricultural land management influence soil quality for a large percentage. The coupled REGCROP-PESERA-ROTHC model allows for quantifying the impact of seasonal and year-to-year crop growth dynamics on soil quality. When coupled to a multi-annual crop

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  12. Soil water infiltration affected by topsoil thickness in row crop and switchgrass production systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Conversion of annual grain crop systems to biofuel production systems can restore soil hydrologic function; however, information on these effects is limited. Hence, the objective of this study was to evaluate the influence of topsoil thickness on water infiltration in claypan soils for grain and swi...

  13. Soil phosphorus compounds in integrated crop-livestock systems of subtropical Brazil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil phosphorus (P) utilization and loss mechanisms may be affected by agricultural complexity, in particular when combining annual and perennial crops and livestock grazing on the same land area and at overlapping time periods. Our objectives were to (i) qualify and quantify soil organic and inorga...

  14. Short-term incorporation of organic manures and biofertilizers influences biochemical and microbial characteristics of soils under an annual crop [Turmeric (Curcuma longa L.)].

    PubMed

    Dinesh, R; Srinivasan, V; Hamza, S; Manjusha, A

    2010-06-01

    The study was conducted to determine whether short-term incorporation of organic manures and biofertilizers influence biochemical and microbial variables reflecting soil quality. For the study, soils were collected from a field experiment conducted on turmeric (Curcuma longa L.) involving organic nutrient management (ONM), chemical nutrient management (CNM) and integrated nutrient management (INM). The findings revealed that application of organic manures and biofertilizers (ONM and INM) positively influenced microbial biomass C, N mineralization, soil respiration and enzymes activities. Contrarily, greater metabolic quotient levels in CNM indicated a stressed soil microbial community. Principal component analysis indicated the strong relationship between microbial activity and the availability of labile and easily mineralizable organic matter. The findings imply that even short-term incorporation of organic manures and biofertilizers promoted soil microbial and enzyme activities and these parameters are sensitive enough to detect changes in soil quality due to short-term incorporation of biological fertilizers.

  15. Differential Soil Acidity Tolerance of Tropical Legume Cover Crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In tropical regions, soil acidity and low soil fertility are the most important yield limiting factors for sustainable crop production. Using legume cover crops as mulch is an important strategy not only to protect the soil loss from erosion but also ameliorating soil fertility. Information is limit...

  16. Topographic and soil influences on root productivity of three bioenergy cropping systems.

    PubMed

    Ontl, Todd A; Hofmockel, Kirsten S; Cambardella, Cynthia A; Schulte, Lisa A; Kolka, Randall K

    2013-08-01

    Successful modeling of the carbon (C) cycle requires empirical data regarding species-specific root responses to edaphic characteristics. We address this need by quantifying annual root production of three bioenergy systems (continuous corn, triticale/sorghum, switchgrass) in response to variation in soil properties across a toposequence within a Midwestern agroecosystem. Using ingrowth cores to measure annual root production, we tested for the effects of topography and 11 soil characteristics on root productivity. Root production significantly differed among cropping systems. Switchgrass root productivity was lowest on the floodplain position, but root productivity of annual crops was not influenced by topography or soil properties. Greater switchgrass root production was associated with high percent sand, which explained 45% of the variation. Percent sand was correlated negatively with soil C and nitrogen and positively with bulk density, indicating this variable is a proxy for multiple important soil properties. Our results suggest that easily measured soil parameters can be used to improve model predictions of root productivity in bioenergy switchgrass, but the edaphic factors we measured were not useful for predicting root productivity in annual crops. These results can improve C cycling modeling efforts by revealing the influence of cropping system and soil properties on root productivity.

  17. Cover cropping and no-tillage improve soil health in arid irrigated cropping systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The impact on soil health of long-term no-tillage (NT) and cover cropping (CC) practices, alone and in combination, was measured and compared with standard tillage (ST) with and without cover crops (NO) in irrigated row crops after 15 years of management in the San Joaquin Valley, CA. Soil aggregat...

  18. Soil residual nitrogen under various crop rotations and cultural practices

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Crop rotation and cultural practice may influence soil residual N available for environmental loss due to crop N uptake and N immobilization. We evaluated the effects of stacked vs. alternate-year crop rotations and cultural practices on soil residual N (NH4-N and NO3-N contents) at the 0-125 cm dep...

  19. Phytoremediation of high phosphorus soil by annual ryegrass and common bermudagrass harvest

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Removal of soil phosphorus (P) in crop harvest is a remediation option for soils high in P. This four-year field-plot study determined P uptake by annual ryegrass (ARG, Lolium multiflorum Lam.) and common bermudagrass (CB, Cynodon dactylon (L.) Pers.) from Ruston soil (fine-loamy, siliceous, thermic...

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

    PubMed

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

    2015-02-01

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

  1. Uncertainty in soil data can outweigh climate impact signals in global crop yield simulations

    PubMed Central

    Folberth, Christian; Skalský, Rastislav; Moltchanova, Elena; Balkovič, Juraj; Azevedo, Ligia B.; Obersteiner, Michael; van der Velde, Marijn

    2016-01-01

    Global gridded crop models (GGCMs) are increasingly used for agro-environmental assessments and estimates of climate change impacts on food production. Recently, the influence of climate data and weather variability on GGCM outcomes has come under detailed scrutiny, unlike the influence of soil data. Here we compare yield variability caused by the soil type selected for GGCM simulations to weather-induced yield variability. Without fertilizer application, soil-type-related yield variability generally outweighs the simulated inter-annual variability in yield due to weather. Increasing applications of fertilizer and irrigation reduce this variability until it is practically negligible. Importantly, estimated climate change effects on yield can be either negative or positive depending on the chosen soil type. Soils thus have the capacity to either buffer or amplify these impacts. Our findings call for improvements in soil data available for crop modelling and more explicit accounting for soil variability in GGCM simulations. PMID:27323866

  2. Micrometeorological measurements over 3 years reveal differences in N2 O emissions between annual and perennial crops.

    PubMed

    Abalos, Diego; Brown, Shannon E; Vanderzaag, Andrew C; Gordon, Robert J; Dunfield, Kari E; Wagner-Riddle, Claudia

    2016-03-01

    Perennial crops can deliver a wide range of ecosystem services compared to annual crops. Some of these benefits are achieved by lengthening the growing season, which increases the period of crop water and nutrient uptake, pointing to a potential role for perennial systems to mitigate soil nitrous oxide (N2 O) emissions. Employing a micrometeorological method, we tested this hypothesis in a 3-year field experiment with a perennial grass-legume mixture and an annual corn monoculture. Given that N2 O emissions are strongly dependent on the method of fertilizer application, two manure application options commonly used by farmers for each crop were studied: injection vs. broadcast application for the perennial; fall vs. spring application for the annual. Across the 3 years, lower N2 O emissions (P < 0.001) were measured for the perennial compared to the annual crop, even though annual N2 O emissions increased tenfold for the perennial after ploughing. The percentage of N2 O lost per unit of fertilizer applied was 3.7, 3.1 and 1.3 times higher for the annual for each consecutive year. Differences in soil organic matter due to the contrasting root systems of these crops are probably a major factor behind the N2 O reduction. We found that a specific manure management practice can lead to increases or reductions in annual N2 O emissions depending on environmental variables. The number of freeze-thaw cycles during winter and the amount of rainfall after fertilization in spring were key factors. Therefore, general manure management recommendations should be avoided because interannual weather variability has the potential to determine if a specific practice is beneficial or detrimental. The lower N2 O emissions of perennial crops deserve further research attention and must be considered in future land-use decisions. Increasing the proportion of perennial crops in agricultural landscapes may provide an overlooked opportunity to regulate N2 O emissions.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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. Cropping sequence and nitrogen fertilization impact on surface residue, soil carbon sequestration, and crop yields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Information is needed on the effect of management practices on soil C storage for obtaining C credit. The effects of tillage, cropping sequence, and N fertilization were evaluated on dryland crop and surface residue C and soil organic C (SOC) at the 0-120 cm depth in a Williams loam from 2006 to 201...

  5. Dryland soil chemical properties and crop yields affected by long-term tillage and cropping sequence

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Information on the effects of long-term tillage and cropping sequence on dryland soil nutrients and chemical properties is scanty. We examined the effect of 30 yr of tillage frequency and cropping sequence combination on dryland soil Olsen-P, exchangeable K, Ca, Mg, Na, SO4-S, and Zn contents, pH, e...

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

    NASA Astrophysics Data System (ADS)

    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

  7. Impacts of crop rotations on soil organic carbon sequestration

    NASA Astrophysics Data System (ADS)

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

    2013-04-01

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

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

    NASA Astrophysics Data System (ADS)

    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.

  9. Traditional agricultural practices enable sustainable remediation of highly polluted soils in Southern Spain for cultivation of food crops.

    PubMed

    Madejón, P; Barba-Brioso, C; Lepp, N W; Fernández-Caliani, J C

    2011-07-01

    This study relates elemental content of a range of edible crops grown in soils severely polluted by metals and metalloids as affected by traditional smallholder management practices. Five agricultural plots close to a sulfidic waste dump were monitored. Soil analysis demonstrated elevated concentrations of As, Cu, Pb and Zn that were greatly in excess of maximum statutory limits for agricultural soils in the studied region. The main vegetables (lettuce, chard, onion, potatoes) and lemon, together with their associated soils, were measured for elemental content. Extractable soil element concentrations were very low. There were differences in elemental accumulation between crops, but none exceeded statutory concentrations in edible parts. Soil-plant transfer factors were uniformly low for all elements and crops. It is concluded that traditional soil management practices (annual liming and application of animal manures) have created conditions for sustainable long-term safety use, with potential for multiple end-use, of these highly polluted soils.

  10. Climate change predicted to negatively influence surface soil health of dryland cropping systems in the Inland Pacific Northwest

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil organic matter (SOM) is a key indicator of agricultural productivity and overall soil health. Currently, dryland cropping systems of the inland Pacific Northwest (iPNW) span a large gradient in mean annual temperature (MAT) and precipitation (MAP). These climatic drivers are major determinants ...

  11. Hyperspectral mapping of crop and soils for precision agriculture

    NASA Astrophysics Data System (ADS)

    Whiting, Michael L.; Ustin, Susan L.; Zarco-Tejada, Pablo; Palacios-Orueta, Alicia; Vanderbilt, Vern C.

    2006-08-01

    Precision agriculture requires high spectral and spatial resolution imagery for advanced analyses of crop and soil conditions to increase environmental protection and producers' sustainability. GIS models that anticipate crop responses to nutrients, water, and pesticides require high spatial detail to generate application prescription maps. While the added precision of geo-spatial interpolation to field scouting generates improved zone maps and are an improvement over field-wide applications, it is limited in detail due to expense, and lacks the high precision required for pixel level applications. Multi-spectral imagery gives the spatial detail required, but broad band indexes are not sensitive to many variables in the crop and soil environment. Hyperspectral imagery provides both the spatial detail of airborne imagery and spectral resolution for spectroscopic and narrow band analysis techniques developed over recent decades in the laboratory that will advance precise determination of water and bio-physical properties of crops and soils. For several years, we have conducted remote sensing investigations to improve cotton production through field spectrometer measurements, and plant and soil samples in commercial fields and crop trials. We have developed spectral analyses techniques for plant and soil conditions through determination of crop water status, effectiveness of pre-harvest defoliant applications, and soil characterizations. We present the most promising of these spectroscopic absorption and narrow band index techniques, and their application to airborne hyperspectral imagery in mapping the variability in crops and soils.

  12. Sustainable biochar effects for low carbon crop production: A 5-crop season field experiment on a low fertility soil from Central China

    NASA Astrophysics Data System (ADS)

    Liu, X.

    2014-12-01

    Biochar's effects on improving soil fertility, enhancing crop productivity and reducing greenhouse gases (GHGs) emission from croplands had been well addressed in numerous short-term experiments with biochar soil amendment (BSA) mostly in a single crop season / cropping year. However, the persistence of these effects, after a single biochar application, has not yet been well known due to limited long-term field studies so far. Large scale BSA in agriculture is often commented on the high cost due to large amount of biochar in a single application. Here, we try to show the persistence of biochar effects on soil fertility and crop productivity improvement as well as GHGs emission reduction, using data from a field experiment with BSA for 5 crop seasons in central North China. A single amendment of biochar was performed at rates of 0 (C0), 20 (C20) and 40 t ha-1 (C40) before sowing of the first crop season. Emissions of CO2, CH4 and N2O were monitored with static closed chamber method throughout the crop growing season for the 1st, 2nd and 5th cropping. Crop yield was measured and topsoil samples were collected at harvest of each crop season. BSA altered most of the soil physic-chemical properties with a significant increase over control in soil organic carbon (SOC) and available potassium (K) content. The increase in SOC and available K was consistent over the 5 crop seasons after BSA. Despite a significant yield increase in the first maize season, enhancement of crop yield was not consistent over crop seasons without corresponding to the changes in soil nutrient availability. BSA did not change seasonal total CO2 efflux but greatly reduced N2O emissions throughout the five seasons. This supported a stable nature of biochar carbon in soil, which played a consistent role in reducing N2O emission, which showed inter-annual variation with changes in temperature and soil moisture conditions. The biochar effect was much more consistent under C40 than under C20 and with

  13. Electrical spectra of undisturbed soil from a crop rotation study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil permittivity can be determined across a range of frequencies, but little is known about how the factors derived from the frequency spectra are related to soil pore structure or crop management. The purpose of this study was to test the use of a 12-wire, quasi-coaxial probe for determining soil ...

  14. Estimation of net greenhouse gas balance using crop- and soil-based approaches: two case studies.

    PubMed

    Huang, Jianxiong; Chen, Yuanquan; Sui, Peng; Gao, Wansheng

    2013-07-01

    The net greenhouse gas balance (NGHGB), estimated by combining direct and indirect greenhouse gas (GHG) emissions, can reveal whether an agricultural system is a sink or source of GHGs. Currently, two types of methods, referred to here as crop-based and soil-based approaches, are widely used to estimate the NGHGB of agricultural systems on annual and seasonal crop timescales. However, the two approaches may produce contradictory results, and few studies have tested which approach is more reliable. In this study, we examined the two approaches using experimental data from an intercropping trial with straw removal and a tillage trial with straw return. The results of the two approaches provided different views of the two trials. In the intercropping trial, NGHGB estimated by the crop-based approach indicated that monocultured maize (M) was a source of GHGs (-1315 kg CO₂(-eq)ha(-1)), whereas maize-soybean intercropping (MS) was a sink (107 kg CO₂(-eq)ha(-1)). When estimated by the soil-based approach, both cropping systems were sources (-3410 for M and -2638 kg CO₂(-eq)ha(-1) for MS). In the tillage trial, mouldboard ploughing (MP) and rotary tillage (RT) mitigated GHG emissions by 22,451 and 21,500 kg CO₂(-eq)ha(-1), respectively, as estimated by the crop-based approach. However, by the soil-based approach, both tillage methods were sources of GHGs: -3533 for MP and -2241 kg CO₂(-eq)ha(-1) for RT. The crop-based approach calculates a GHG sink on the basis of the returned crop biomass (and other organic matter input) and estimates considerably more GHG mitigation potential than that calculated from the variations in soil organic carbon storage by the soil-based approach. These results indicate that the crop-based approach estimates higher GHG mitigation benefits compared to the soil-based approach and may overestimate the potential of GHG mitigation in agricultural systems.

  15. Herbaceous Energy Crops Program. Annual progress report for FY 1985

    SciTech Connect

    Cushman, J.H.; Turhollow, A.F.; Johnston, J.W.

    1986-04-01

    This report describes the activities and accomplishments of the Herbaceous Energy Crops Program (HECP) for the year ending September 30, 1985. HECP emphasizes lignocellulosic forage crops. In FY 1985 screening and selection trails began on seven species of perennial and annual grasses and legumes in five projects in the Southeast and the Midwest-Lake State regions. Research also continued on the development of winter rapeseed as a disel-fuel substitute. Activities in FY 1985 included crosses and selections to incorporate atrazine resistance and reduced vernalization requirements in genotypes with desirable seed and oil qualities. Exploratory research efforts in FY 1985 included the physiology and biochemistry of hydrocarbon production in latex bearing plants, the productivity of cattail stands under sustained harvesting, and the development of tissue culture techniques for hard-to-culture sorghum genotypes. Environmental and economic analyses in FY 1985 included completion of a resource assessment of the southwestern United States, a study on successful new crop introductions, and initiation of studies on near-term markets for lignocellulosic energy crops and on vegetable oil extraction facilities. 8 figs., 2 tabs.

  16. [Effects of transgenic crops on soil microorganisms: a review].

    PubMed

    Zhang, Yan-Jun; Xie, Ming; Peng, De-Liang

    2013-09-01

    The worldwide cultivation of transgenic crops not only provides tremendous economic benefits, but also induces the concern about the potential risks of transgenic crops on soil ecosystem in which microorganisms are involved. The potential effects of transgenic crops on soil microorganisms include the direct effects of the transgenic proteins on non-target soil microorganisms, and the indirect effects of the unintentional changes in the chemical compositions of root exudates induced by the introduction of the exogenous transgenic proteins. Most of the studies on transgenic crops suggested that transgenic crops could affect the quantity and structure of soil microbial populations. However, the perceivable effects on the soil microorganisms are inconsistent, with some in significant and others in non-significant, or some with persistent and others with non-persistent. This paper summarized the effects of different transgenic crops on soil microorganisms, and discussed the factors affecting the assessment reliability, including the species of transgenic crops and the experimental technologies and principles. Some issues needed to be paid special attention to in the future studies were put forward.

  17. Soil Nitrogen Response to Coupling Cover Crops with Manure Injection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Coupling winter small grain cover crops (CC) with manure (M) application may increase retention of manure nitrogen (N) in corn-soybean cropping systems. The objective of this research was to quantify soil N changes after application of liquid swine M (Sus scrofa L.) at target N rates of 112, 224, an...

  18. Relating soil biochemistry to sustainable crop production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Amino acids, amino sugars, carbohydrates, phenols, and fatty acids together comprise appreciable proportions of soil organic matter (SOM). Their cycling contribute to soil processes, including nitrogen availability, carbon sequestration and aggregation. For example, soil accumulation of phenols has ...

  19. Estimating Annual Soil Carbon Loss in Agricultural Peatland Soils Using a Nitrogen Budget Approach

    PubMed Central

    Kirk, Emilie R.; van Kessel, Chris; Horwath, William R.; Linquist, Bruce A.

    2015-01-01

    Around the world, peatland degradation and soil subsidence is occurring where these soils have been converted to agriculture. Since initial drainage in the mid-1800s, continuous farming of such soils in the California Sacramento-San Joaquin Delta (the Delta) has led to subsidence of up to 8 meters in places, primarily due to soil organic matter (SOM) oxidation and physical compaction. Rice (Oryza sativa) production has been proposed as an alternative cropping system to limit SOM oxidation. Preliminary research on these soils revealed high N uptake by rice in N fertilizer omission plots, which we hypothesized was the result of SOM oxidation releasing N. Testing this hypothesis, we developed a novel N budgeting approach to assess annual soil C and N loss based on plant N uptake and fallow season N mineralization. Through field experiments examining N dynamics during growing season and winter fallow periods, a complete annual N budget was developed. Soil C loss was calculated from SOM-N mineralization using the soil C:N ratio. Surface water and crop residue were negligible in the total N uptake budget (3 – 4 % combined). Shallow groundwater contributed 24 – 33 %, likely representing subsurface SOM-N mineralization. Assuming 6 and 25 kg N ha-1 from atmospheric deposition and biological N2 fixation, respectively, our results suggest 77 – 81 % of plant N uptake (129 – 149 kg N ha-1) was supplied by SOM mineralization. Considering a range of N uptake efficiency from 50 – 70 %, estimated net C loss ranged from 1149 – 2473 kg C ha-1. These findings suggest that rice systems, as currently managed, reduce the rate of C loss from organic delta soils relative to other agricultural practices. PMID:25822494

  20. Estimating annual soil carbon loss in agricultural peatland soils using a nitrogen budget approach.

    PubMed

    Kirk, Emilie R; van Kessel, Chris; Horwath, William R; Linquist, Bruce A

    2015-01-01

    Around the world, peatland degradation and soil subsidence is occurring where these soils have been converted to agriculture. Since initial drainage in the mid-1800s, continuous farming of such soils in the California Sacramento-San Joaquin Delta (the Delta) has led to subsidence of up to 8 meters in places, primarily due to soil organic matter (SOM) oxidation and physical compaction. Rice (Oryza sativa) production has been proposed as an alternative cropping system to limit SOM oxidation. Preliminary research on these soils revealed high N uptake by rice in N fertilizer omission plots, which we hypothesized was the result of SOM oxidation releasing N. Testing this hypothesis, we developed a novel N budgeting approach to assess annual soil C and N loss based on plant N uptake and fallow season N mineralization. Through field experiments examining N dynamics during growing season and winter fallow periods, a complete annual N budget was developed. Soil C loss was calculated from SOM-N mineralization using the soil C:N ratio. Surface water and crop residue were negligible in the total N uptake budget (3 - 4 % combined). Shallow groundwater contributed 24 - 33 %, likely representing subsurface SOM-N mineralization. Assuming 6 and 25 kg N ha-1 from atmospheric deposition and biological N2 fixation, respectively, our results suggest 77 - 81 % of plant N uptake (129 - 149 kg N ha-1) was supplied by SOM mineralization. Considering a range of N uptake efficiency from 50 - 70 %, estimated net C loss ranged from 1149 - 2473 kg C ha-1. These findings suggest that rice systems, as currently managed, reduce the rate of C loss from organic delta soils relative to other agricultural practices.

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

    PubMed Central

    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 NO3--N 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 NO3--N 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 NO3--N by 35% on depression, 20% on slope and 32% on summit positions. Rye cover crop had a significant 15% negative effect on NO3--N 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 agricultural systems. PMID:26600462

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

    PubMed

    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

  3. Plant, soil, and shadow reflectance components of row crops

    NASA Technical Reports Server (NTRS)

    Richardson, A. J.; Wiegand, C. L.; Gausman, H. W.; Cuellar, J. A.; Gerbermann, A. H.

    1975-01-01

    Data from the first Earth Resource Technology Satellite (LANDSAT-1) multispectral scanner (MSS) were used to develop three plant canopy models (Kubelka-Munk (K-M), regression, and combined K-M and regression models) for extracting plant, soil, and shadow reflectance components of cropped fields. The combined model gave the best correlation between MSS data and ground truth, by accounting for essentially all of the reflectance of plants, soil, and shadow between crop rows. The principles presented can be used to better forecast crop yield and to estimate acreage.

  4. Dryland soil chemical properties and crop yields affected by long-term tillage and cropping sequence

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Information on the effect of long-term management on soil nutrients and chemical properties is scanty. We examined the 30-yr effect of tillage frequency and cropping sequence combination on dryland soil Olsen-P, K, Ca, Mg, Na, SO4-S, and Zn concentrations, pH, electrical conductivity (EC), and catio...

  5. Cover cropping impacts on arbuscular mycorrhizal fungi and soil aggregation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cover crops are a management tool which can extend the period of time that a living plant is growing and conducting photosynthesis. This is critical for soil health, because most of the soil organisms, particularly the arbuscular mycorrhizal fungi, are limited by carbon. Research, on-farm, and demon...

  6. Soil-to-crop transfer factors of tellurium.

    PubMed

    Yang, Guosheng; Zheng, Jian; Tagami, Keiko; Uchida, Shigeo

    2014-09-01

    Stable tellurium (Te) concentrations in 148 sets of agricultural soil and associated crop samples were measured in this study to obtain soil-to-crop transfer factor (TF) of Te. We used a recently developed simple method that applies digestion of samples with aqua regia and sector field inductively coupled plasma mass spectrometry to measure low Te levels in these samples. Geometric mean (GM) concentrations of Te in soil and crops were 75μgkg(-1)-dry (range: 15-850μgkg(-1)-dry) and 1.8μgkg(-1)-dry (range: 0.1-120μgkg(-1)-dry), respectively; the Te concentration range was significantly wider in crops than in soil. Using these data, we calculated TFs and obtained their range from 1.3×10(-3) to 1.1×10(-1). The GM of TF for upland field crops was calculated to be 2.0×10(-2) and for brown rice was 3.1×10(-2); all crop types had the similar GMs of their TF values. Data comparison for TF of Te was carried out with six elements, which are present in anionic forms in soil environment like Te is, i.e. P, Br, As, Se, Mo, and I. TFs of Te and I showed the highest correlation factor for upland field crops by t-test (r=0.577, p<0.001), but no correlation was found for brown rice. We considered it likely that different water management practices in upland fields and paddy fields affected the Te transfer from soil to crops.

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

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

    Agricultural production systems that include complimentary plant, soil and animal interaction contribute to sustainability. In sustainable livestock systems integrated with crop production, the soil resource is impacted positively. The goal of this research was to maximize beef cattle and crop economic yield, while improving the soil resource by increasing soil organic matter (SOM) and subsequently seasonal soil nitrogen fertility over a 5-year period (2011-2015). Each experimental crop field used in the study was 1.74 ha. Small-seeded crops were planted using a JD 1590 No-Till drill. Corn (C) and sunflowers (SF) were planted using a JD 7000 No-Till planter. The cropping sequence used in the study was SF, hard red spring wheat (HRSW), fall seeded winter triticale-hairy vetch (T-HV), spring harvested for hay/mid-June seeded 7-species cover crop (CC; SF, Everleaf Oat, Flex Winter Pea, HV, Winfred Forage Rape, Ethiopian Cabbage, Hunter Leaf Turnip), C (85-day var.), and field pea-barley intercrop (PBY). The HRSW and SF were harvested as cash crops and the PBY, C, and CC were harvested by grazing cattle. In the system, yearling beef steers grazed PBY and unharvested C before feedlot entry, and after weaning, gestating cows grazed CC. Seasonal soil nitrogen fertility was measured at 0-15, 15-30, and 30-61 cm depths approximately every two weeks from June to October, 2014. The regression illustrating the relationship between SOM and average seasonal available mineral nitrogen shows that for each percentage increase in SOM there is a corresponding N increase of 1.47 kg/ha. Nitrogen fertilizer applications for the 5-year period of the study were variable; however, the overall trend was for reduced fertilizer requirement as SOM increased. At the same time, grain, oilseed, and annual forage crop yields increased year over year (2011-2015) except for the 2014 crop year, when above average precipitation delayed seeding and early frost killed the C and SF crops prematurely

  8. Soil carbon and soil organic matter quality in soil size fractions from crop and livestock systems in Texas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cotton based rotations and monocultures in the Southern High Plains have resulted in soil quality degradation because the semiarid environment combined with low crop residue returns has diminished soil C. Integrated crop-livestock systems and no-till based rotations can increase soil C when used as ...

  9. Biological Features of the Soil: Advanced Crop and Soil Science. A Course of Study.

    ERIC Educational Resources Information Center

    Miller, Larry E.

    The course of study represents the third of six modules in advanced crop and soil science and introduces the agriculture student to biological features of soil. Upon completing the two day lesson, the student will: (1) realize the vast amount of life present in the soil, (2) be able to list representative animal and plant life in the soil by size,…

  10. Physical Features of Soil: Advanced Crop and Soil Science. A Course of Study.

    ERIC Educational Resources Information Center

    Miller, Larry E.

    The course of study represents the second of six modules in advanced crop and soil science and introduces the agriculture student to the subject of physical features of the soil. Upon completing the two day lesson, the student will be able to determine the texture and structural types of soil, list the structural classes of the soil and where they…

  11. Soil Water: Advanced Crop and Soil Science. A Course of Study.

    ERIC Educational Resources Information Center

    Miller, Larry E.

    The course of study represents the fourth of six modules in advanced crop and soil science and introduces the agriculture student to the topic of soil water. Upon completing the three day module, the student will be able to classify water as to its presence in the soil, outline the hydrological cycle, list the ways water is lost from the soil,…

  12. Replacing fallow with cover crops in a semiarid soil: effects on soil properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Replacement of fallow in crop-fallow systems with cover crops (CCs) may improve soil properties. We assessed whether replacing fallow in no-till winter wheat (Triticum aestivum L.)-fallow with winter and spring CCs for five years reduced wind and water erosion, increased soil organic carbon (SOC), a...

  13. Crop Performance and Soil Properties in Two Artificially-Eroded Soils in North-Central Alberta

    SciTech Connect

    Izaurralde, R Cesar C.; Malhi, S. S.; Nyborg, M.; Solberg, E. D.; Quiroga Jakas, Maria C.

    2006-09-01

    Field experiments were conducted from 1991 to 1995 at Josephburg (Orthic Black Chernozem, Typic Cryoboroll) and Cooking Lake (Orthic Gray Luvisol, Typic Cryoboralf), Alberta, to determine impact of topsoil removal on selected soil properties, N-mineralization potential and crop yield, and effectiveness of various amendments for restoring the productivity of eroded soils. The simulated-erosion levels were established in the autumn of 1990 by removing 20 cm topsoil in 5-cm depth increments. The four amendments were: control, addition of 5 cm of topsoil, fertilizers to supply 100 kg N ha-1 and 20 kg P ha-1, and cattle manure at 75 Mg ha-1. Topsoil and manure were applied once in the autumn of 1990, while fertilizers were applied annually from 1991 to 1995. Available N and P, total C, N and P, and N-mineralization potential decreased, while bulk density increased with increasing depth of topsoil removal. Tiller number, plant height, spike density, thousand kernel weight, and leaf area index decreased with simulated erosion. Grain yield reductions due to simulated soil erosion were either linear or curvilinear functions of nutrient removal. Application of N and P fertilizers and manure improved grain yield and reduced the impact of yield loss due to erosion. Return of 5 cm of topsoil also increased grain yield, but to a lesser extent than manure or fertilizers. Grain yields were maximized when fertilizers were also applied to organic amendment treatments. In conclusion, the findings suggest the importance of integrated use of organic amendments and chemical fertilizers for best crop yields on severely-eroded soils.

  14. Crop Management Effects on Crop Residue Production and Changes in Soil Organic Carbon in the Central Great Plains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Crop biomass has been proposed as a source stock for bioethanol production. Acceptable levels of crop residue removal must be determined to prevent loss of soil organic carbon (SOC) and the degradation of soil physical and chemical properties resulting from SOC loss. Crop residue inputs and changes ...

  15. Cover crops effectiveness for soil erosion control in Sicilian vineyard

    NASA Astrophysics Data System (ADS)

    Gristina, L.; Novara, A.; Saladino, S.; Santoro, A.

    2009-04-01

    In vineyards, which are very common in Mediterranean area, cover crops are becoming increasingly used to reduce soil erosion. Cover crops reduce runoff by increasing infiltration and increasing roughness and then reducing the ovelandflow velocity. The aim of the present study was to quantify soil and water losses under different soil managements systems on vineyards. The study site was a Sauvignon blanc winegrape vineyard located in Southwestern Sicily. Vineyards were managed both traditionally (conventional tillage) and alternative management using cover crops: 1) Vicia faba ; 2) Vicia faba and Vicia sativa; 3) Trifolium subterraneum, Lolium perenne, Festuca rubra; 4)Trifolium subterraneum, Festuca rubra and Festuca ovina, 5) Triticum durum, 6) Triticum durum and Vicia sativa. To monitor water and sediment yield, a Gerlach trough was installed at each treatment on the vineyard inter-row, with the row vineyard used as a border (topographical border). Runoff was measured after each rainfall event (raingauge 0.2 mm accuracy) from November 2005 to April 2007. And sediments were measured after desiccation. The results show that runoff and erosion were reduced considerably under the treatments with Trifolium subterraneum, Lolium perenne, Festuca rubra and Trifolium subterraneum, Festuca rubra and Festuca ovina (treatments 3 and 4). The soil losses were reduced by 73% under treatment 4 compared to the tillage plot. Conventional tillage and alternative management using Vicia faba cover crop (treatment 1) result the most ineffective treatment to soil erosion. These results show that the use of a cover crop can be a simple soil and water conservation practice in Sicilian vineyards. Key words: soil erosion, cover crops, vineyard, Mediterranean area.

  16. Soil erosion control, plant diversity, and arthropod communities under heterogeneous cover crops in an olive orchard.

    PubMed

    Gómez, José Alfonso; Campos, Mercedes; Guzmán, Gema; Castillo-Llanque, Franco; Vanwalleghem, Tom; Lora, Ángel; Giráldez, Juan V

    2017-01-30

    A 3-year experiment compared in an olive orchard the effect of different cover crops' composition on runoff, water erosion, diversity of annual plants, and arthropod communities which could provide an alternative to conventional management based on tillage (CT). The cover crops evaluated were a seeded homogeneous grass (GC), a seeded mix of ten different species (MCseeded), and a non-seeded cover by vegetation naturally present at the farm after 20 years of mowing (MCnatural). The results suggest that heterogeneous cover crops can provide a viable alternative to homogeneous ones in olives, providing similar benefits in reducing runoff and soil losses compared to management based on bare soil. The reduction in soil loss was particularly large: 46.7 in CT to 6.5 and 7.9 t ha(-1) year(-1) in GC and MCseeded, respectively. The heterogeneous cover crops resulted in greater diversity of plant species and a modification of the arthropod communities with an increased number of predators for pests. The reduction of the cost of implanting heterogeneous cover crops, improvement of the seeding techniques, and selection of species included in the mixes require additional research to promote the use of this practice which can deliver enhanced environmental benefits.

  17. Remote sensing of agricultural crops and soils

    NASA Technical Reports Server (NTRS)

    Bauer, M. E. (Principal Investigator)

    1983-01-01

    Research in the correlative and noncorrelative approaches to image registration and the spectral estimation of corn canopy phytomass and water content is reported. Scene radiation research results discussed include: corn and soybean LANDSAT MSS classification performance as a function of scene characteristics; estimating crop development stages from MSS data; the interception of photosynthetically active radiation in corn and soybean canopies; costs of measuring leaf area index of corn; LANDSAT spectral inputs to crop models including the use of the greenness index to assess crop stress and the evaluation of MSS data for estimating corn and soybean development stages; field research experiment design data acquisition and preprocessing; and Sun-view angles studies of corn and soybean canopies in support of vegetation canopy reflection modeling.

  18. DAYCENT national-scale simulations of nitrous oxide emissions from cropped soils in the United States.

    PubMed

    Del Grosso, S J; Parton, W J; Mosier, A R; Walsh, M K; Ojima, D S; Thornton, P E

    2006-01-01

    Until recently, Intergovernmental Panel on Climate Change (IPCC) emission factor methodology, based on simple empirical relationships, has been used to estimate carbon (C) and nitrogen (N) fluxes for regional and national inventories. However, the 2005 USEPA greenhouse gas inventory includes estimates of N2O emissions from cultivated soils derived from simulations using DAYCENT, a process-based biogeochemical model. DAYCENT simulated major U.S. crops at county-level resolution and IPCC emission factor methodology was used to estimate emissions for the approximately 14% of cropped land not simulated by DAYCENT. The methodology used to combine DAYCENT simulations and IPCC methodology to estimate direct and indirect N2O emissions is described in detail. Nitrous oxide emissions from simulations of presettlement native vegetation were subtracted from cropped soil N2O to isolate anthropogenic emissions. Meteorological data required to drive DAYCENT were acquired from DAYMET, an algorithm that uses weather station data and accounts for topography to predict daily temperature and precipitation at 1-km2 resolution. Soils data were acquired from the State Soil Geographic Database (STATSGO). Weather data and dominant soil texture class that lie closest to the geographical center of the largest cluster of cropped land in each county were used to drive DAYCENT. Land management information was implemented at the agricultural-economic region level, as defined by the Agricultural Sector Model. Maps of model-simulated county-level crop yields were compared with yields estimated by the USDA for quality control. Combining results from DAYCENT simulations of major crops and IPCC methodology for remaining cropland yielded estimates of approximately 109 and approximately 70 Tg CO2 equivalents for direct and indirect, respectively, mean annual anthropogenic N2O emissions for 1990-2003.

  19. [Use of Remote Sensing for Crop and Soil Analysis

    NASA Technical Reports Server (NTRS)

    Johannsen, Chris J.

    1997-01-01

    The primary agricultural objective of this research is to determine what soil and crop information can be verified from remotely sensed images during the growing season. Specifically: (1) Elements of crop stress due to drought, weeds, disease and nutrient deficiencies will be documented with ground truth over specific agricultural sites and (2) Use of remote sensing with GPS and GIS technology for providing a safe and environmentally friendly application of fertilizers and chemicals will be documented.

  20. Long-term trends in nitrous oxide emissions, soil nitrogen, and crop yields of till and no-till cropping systems.

    PubMed

    Grandy, A Stuart; Loecke, Terrance D; Parr, Sara; Robertson, G Philip

    2006-01-01

    No-till cropping can increase soil C stocks and aggregation but patterns of long-term changes in N2O emissions, soil N availability, and crop yields still need to be resolved. We measured soil C accumulation, aggregation, soil water, N2O emissions, soil inorganic N, and crop yields in till and no-till corn-soybean-wheat rotations between 1989 and 2002 in southwestern Michigan and investigated whether tillage effects varied over time or by crop. Mean annual NO3- concentrations in no-till were significantly less than in conventional till in three of six corn years and during one year of wheat production. Yields were similar in each system for all 14 years but three, during which yields were higher in no-till, indicating that lower soil NO3- concentrations did not result in lower yields. Carbon accumulated in no-till soils at a rate of 26 g C m(-2) yr(-1) over 12 years at the 0- to 5-cm soil depth. Average nitrous oxide emissions were similar in till (3.27 +/- 0.52 g N ha d(-1)) and no-till (3.63 +/- 0.53 g N ha d(-1)) systems and were sufficient to offset 56 to 61% of the reduction in CO2 equivalents associated with no-till C sequestration. After controlling for rotation and environmental effects by normalizing treatment differences between till and no-till systems we found no significant trends in soil N, N2O emissions, or yields through time. In our sandy loam soils, no-till cropping enhances C storage, aggregation, and associated environmental processes with no significant ecological or yield tradeoffs.

  1. Soil, Plant, and Crop Science. Teacher Edition.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This package contains an instructor's manual, an instructor's resource package, and a student workbook for a course in agricultural production and management as it relates to crop production. The module contains 17 units of instruction, each of which contains some or all of the following components: objective sheet, instructor's guide, information…

  2. Living cover crops have immediate impacts on soil microbial community structure and function

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cover cropping is a widely promoted strategy to enhance soil health in agricultural systems. Despite a substantial body of literature demonstrating links between cover crops and soil biology, an important component of soil health, research evaluating how specific cover crop species influence soil mi...

  3. Belowground environmental effects of transgenic crops: a soil microbial perspective.

    PubMed

    Turrini, Alessandra; Sbrana, Cristiana; Giovannetti, Manuela

    2015-04-01

    Experimental studies investigated the effects of transgenic crops on the structure, function and diversity of soil and rhizosphere microbial communities playing key roles in belowground environments. Here we review available data on direct, indirect and pleiotropic effects of engineered plants on soil microbiota, considering both the technology and the genetic construct utilized. Plants modified to express phytopathogen/phytoparasite resistance, or traits beneficial to food industries and consumers, differentially affected soil microorganisms depending on transformation events, experimental conditions and taxa analyzed. Future studies should address the development of harmonized methodologies by taking into account the complex interactions governing soil life.

  4. Modeled Impacts of Cover Crops and Vegetative Barriers on Corn Stover Availability and Soil Quality

    SciTech Connect

    Ian J. Bonner; David J. Muth Jr.; Joshua B. Koch; Douglas L. Karlen

    2014-06-01

    Environmentally benign, economically viable, and socially acceptable agronomic strategies are needed to launch a sustainable lignocellulosic biofuel industry. Our objective was to demonstrate a landscape planning process that can ensure adequate supplies of corn (Zea mays L.) stover feedstock while protecting and improving soil quality. The Landscape Environmental Assessment Framework (LEAF) was used to develop land use strategies that were then scaled up for five U.S. Corn Belt states (Nebraska, Iowa, Illinois, Indiana, and Minnesota) to illustrate the impact that could be achieved. Our results show an annual sustainable stover supply of 194 million Mg without exceeding soil erosion T values or depleting soil organic carbon [i.e., soil conditioning index (SCI)?>?0] when no-till, winter cover crop, and vegetative barriers were incorporated into the landscape. A second, more rigorous conservation target was set to enhance soil quality while sustainably harvesting stover. By requiring erosion to be <1/2 T and the SCI-organic matter (OM) subfactor to be >?0, the annual sustainable quantity of harvestable stover dropped to148 million Mg. Examining removal rates by state and soil resource showed that soil capability class and slope generally determined the effectiveness of the three conservation practices and the resulting sustainable harvest rate. This emphasizes that sustainable biomass harvest must be based on subfield management decisions to ensure soil resources are conserved or enhanced, while providing sufficient biomass feedstock to support the economic growth of bioenergy enterprises.

  5. [Influence of double rice cropping system innovation on paddy soil profile form and soil characteristics].

    PubMed

    Zeng, Xi-Bai; Sun, Nan; Gao, Ju-Sheng; Li, Lian-Fang; Wang, Bo-Ren; Bai, Ling-Yu

    2008-05-01

    Field experiments were conducted on the double rice cropping paddy field in red soil area to evaluate the influence of cropping system innovation on soil profile form and related soil characteristics. Four cropping systems of rice-rice-Chinese Milkvetch (Astragalus sinicus Linn.), forage, paddy-upland rotation, and upland were substituted for the double rice cropping system. The results indicated that compared with those under double rice cropping system, the thickness of cultivated horizon under upland cropping system increased by 4 cm, that of plow pan declined by 2 cm, > 2 mm aggregates in wet-sieved particle-size fractions increased by 6.94%, wet-sieved mean-mass diameter increased by 0.37 mm, contents of humic acid carbon and fulvic acid carbon increased by 0.15 and 0.49 g kg(-1), respectively, and quotient of aggregates water stability was 0.78 times higher. Under paddy-upland rotation, the quotient of aggregates water stability was higher (95.86), while soil nutrient contents changed a little. Under rice-rice-Chinese Milkvetch system, soil organic matter content increased by 1.3 g kg(-1), quotient of aggregates water stability declined by 8.82, but other parameters had less changes. Under forage system, the thickness of cultivated and transitional horizons increased by 2 cm and 9 cm, respectively, quotient of aggregates water stability increased by 1.39, while the contents of soil organic matter and total potassium decreased by 5.6 and 2.8 g kg(-1), respectively. Among all test cropping systems, forage system had the greatest changes in soil characteristics. It was completely feasible to substitute the local double rice cropping system for paddy-upland rotation or upland cropping, particularly in the areas where full irrigation was not available. However, attention should be paid to the decrease of soil potassium content when the cropping system innovation was practiced.

  6. Carbon dioxide exchange of a perennial bioenergy crop cultivation on a mineral soil

    NASA Astrophysics Data System (ADS)

    Lind, S. E.; Shurpali, N. J.; Peltola, O.; Mammarella, I.; Hyvönen, N.; Maljanen, M.; Räty, M.; Virkajärvi, P.; Martikainen, P. J.

    2015-10-01

    One of the strategies to reduce carbon dioxide (CO2) emissions from the energy sector is to increase the use of renewable energy sources such as bioenergy crops. Bioenergy is not necessarily carbon neutral because of greenhouse gas (GHG) emissions during biomass production, field management and transportation. The present study focuses on the cultivation of reed canary grass (RCG, Phalaris arundinaceae L.), a perennial bioenergy crop, on a mineral soil. To quantify the CO2 exchange of this RCG cultivation system, and to understand the key factors controlling its CO2 exchange, the net ecosystem CO2 exchange (NEE) was measured during three years using the eddy covariance (EC) method. The RCG cultivation thrived well producing yields of 6200 and 6700 kg DW ha-1 in 2010 and 2011, respectively. Gross photosynthesis (GPP) was controlled mainly by radiation from June to September. Vapour pressure deficit (VPD), air temperature or soil moisture did not limit photosynthesis during the growing season. Total ecosystem respiration (TER) increased with soil temperature, green area index and GPP. Annual NEE was -262 and -256 g C m-2 in 2010 and 2011, respectively. Throughout the studied period, cumulative NEE was -575 g C m-2. When compared to the published data for RCG on an organic soil, the cultivation of this crop on a mineral soil had higher capacity to take up CO2 from the atmosphere.

  7. Detection of anomalous crop condition and soil variability mapping using a 26 year Landsat record and the Palmer crop moisture index

    NASA Astrophysics Data System (ADS)

    Venteris, E. R.; Tagestad, J. D.; Downs, J. L.; Murray, C. J.

    2015-07-01

    Cost-effective and reliable vegetation monitoring methods are needed for applications ranging from traditional agronomic mapping, to verifying the safety of geologic injection activities. A particular challenge is defining baseline crop conditions and subsequent anomalies from long term imagery records (Landsat) in the face of large spatiotemporal variability. We develop a new method for defining baseline crop response (near peak growth) using the normalized difference vegetation index (NDVI) from 26 years (1986-2011) of Landsat data for 400 km2 surrounding a planned geologic carbon sequestration site near Jacksonville, Illinois. The normal score transform (yNDVI) was applied on a field by field basis to accentuate spatial patterns and level differences due to planting times. We tested crop type and soil moisture (Palmer crop moisture index (CMI)) as predictors of expected crop condition. Spatial patterns in yNDVI were similar between corn and soybeans - the two major crops. Linear regressions between yNDVI and the cumulative CMI (CCMI) exposed complex interactions between crop condition, field location (topography and soils), and annual moisture. Wet toposequence positions (depressions) were negatively correlated to CCMI and dry positions (crests) positively correlated. However, only 21% of the landscape showed a statistically significant (p < 0.05) linear relationship. To map anomalous crop conditions, we defined a tolerance interval based on yNDVI statistics. Tested on an independent image (2013), 63 of 1483 possible fields showed unusual crop condition. While the method is not directly suitable for crop health assessment, the spatial patterns in correlation between yNDVI and CCMI have potential applications for pest damage detection and edaphological soil mapping, especially in the developing world.

  8. Crop diversity effects on soil health

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Concurrent demands for abundant, healthy food, thriving rural economies, and an unpolluted physical environment represents a significant agricultural challenge in the 21st century. Trends in human population growth and changing weather patterns will make this challenge exceedingly difficult. Soil ...

  9. Soil factors associated with zinc deficiency in crops and humans.

    PubMed

    Alloway, B J

    2009-10-01

    Zinc deficiency is the most ubiquitous micronutrient deficiency problem in world crops. Zinc is essential for both plants and animals because it is a structural constituent and regulatory co-factor in enzymes and proteins involved in many biochemical pathways. Millions of hectares of cropland are affected by Zn deficiency and approximately one-third of the human population suffers from an inadequate intake of Zn. The main soil factors affecting the availability of Zn to plants are low total Zn contents, high pH, high calcite and organic matter contents and high concentrations of Na, Ca, Mg, bicarbonate and phosphate in the soil solution or in labile forms. Maize is the most susceptible cereal crop, but wheat grown on calcareous soils and lowland rice on flooded soils are also highly prone to Zn deficiency. Zinc fertilizers are used in the prevention of Zn deficiency and in the biofortification of cereal grains.

  10. Anaerobic Soil Disinfestation (ASD) Combined with Soil Solarization as a Methyl Bromide Alternative: Vegetable Crop Performance and Soil Nutrient Dynamics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil treatment by anaerobic soil disinfestation (ASD) combined with soil solarization can effectively control soilborne plant pathogens and plant-parasitic nematodes in specialty crop production systems. At the same time, research is limited on the impact of soil treatment by ASD + solarization on c...

  11. Chemical control of perennial and annual weeds in herbicide resistant soybean crops.

    PubMed

    Sarpe, N; Roibu, C; Negrila, E; Bodescu, F; Fuia, S; Popa, C; Beraru, C

    2001-01-01

    In Romania, the first tests with Roundup Ready on soybean crops were performed in 1998, on 2 soil types: a) at Teleorman Station on chernozem containing 3.5% humus, 4.5% clay b) at Brăila Station placed in Danube Meadow on alluvial soil containing 3.90% humus and 46% clay. In every locality cultivated soybean cultivar S.2254 was resistant to glyphosate. During the three years of experiments (1998-2000) the crop of soybean was infested with various species of weeds (both annual and perennial) of which the most important are: Sorghum halepense (60-80%), Echinochloa crus-galli, Setaria glauca, Amaranthus retroflexus, Solarium nigrum, Yanthium italicum, Abutilon theoprasthi, Sinapis arvensis, Datum stramonium, Polygonum persicaria, Calystegia sepium, Cirsium arvense. In 3 years of experience the best weed control and the highest soybean production were obtained in the variants treated 2 times postemergent with Roundup Ready at a dose of 3 + 3 l/ha. Similar results were also obtained in the farms of the Academy of Agricultural Forestry Sciences, where GMO soybean was cultivated on 1500 hectares.

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

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

    Vegetable Research Centre East-Flanders Karreweg 6, 9770 Kruishoutem, Belgium A long term trial for soil improvement by organic fertilization was carried out in Kruishoutem from 2001 till 2010 in a vegetable rotation (carrots - leek - lettuce (2/year) - cauliflower (2/year) - leek - carrots - lettuce (2/year) - cauliflower (2/year) - leek and spinach). The trial compared yearly applications of 30 m²/ha of three types of compost (green compost, vfg-compost and spent mushroom compost) with an untreated object which did not receive any organic fertilization during the trial timescale. The organic fertilization was applied shortly before the cropping season. Looking at the soil quality, effects of organic fertilization manifest rather slow. The first four years after the beginning of the trial, no increase in carbon content of the soil is detectable yet. Although, mineralization of the soil has increased. The effect on the mineralization is mainly visible in crops with a lower N uptake (e.g. carrots) leading to a higher nitrate residue after harvest. Effects on soil structure and compaction occur rather slowly although, during the first two cropping seasons compost applications increase the water retention capacity of the soil. Compost increases the pH of the soil from the first year on till the end of the trial in 2010. Thus, organic fertilization impedes acidification in light sandy soils. Also soil fertility benefits from compost by an increase in K-, Ca- and Mg- content in the soil from the second year on. After 10 years of organic fertilization, yield and quality of spinach were increased significantly (p<0.05) compared to the untreated object. Also leek (2002 and 2009) and lettuce (2003 and 2007) benefit from organic fertilization.

  13. Soil carbon and nitrogen fractions and crop yields affected by residue placement and crop types.

    PubMed

    Wang, Jun; Sainju, Upendra M

    2014-01-01

    Soil labile C and N fractions can change rapidly in response to management practices compared to non-labile fractions. High variability in soil properties in the field, however, results in nonresponse to management practices on these parameters. We evaluated the effects of residue placement (surface application [or simulated no-tillage] and incorporation into the soil [or simulated conventional tillage]) and crop types (spring wheat [Triticum aestivum L.], pea [Pisum sativum L.], and fallow) on crop yields and soil C and N fractions at the 0-20 cm depth within a crop growing season in the greenhouse and the field. Soil C and N fractions were soil organic C (SOC), total N (STN), particulate organic C and N (POC and PON), microbial biomass C and N (MBC and MBN), potential C and N mineralization (PCM and PNM), NH4-N, and NO3-N concentrations. Yields of both wheat and pea varied with residue placement in the greenhouse as well as in the field. In the greenhouse, SOC, PCM, STN, MBN, and NH4-N concentrations were greater in surface placement than incorporation of residue and greater under wheat than pea or fallow. In the field, MBN and NH4-N concentrations were greater in no-tillage than conventional tillage, but the trend reversed for NO3-N. The PNM was greater under pea or fallow than wheat in the greenhouse and the field. Average SOC, POC, MBC, PON, PNM, MBN, and NO3-N concentrations across treatments were higher, but STN, PCM and NH4-N concentrations were lower in the greenhouse than the field. The coefficient of variation for soil parameters ranged from 2.6 to 15.9% in the greenhouse and 8.0 to 36.7% in the field. Although crop yields varied, most soil C and N fractions were greater in surface placement than incorporation of residue and greater under wheat than pea or fallow in the greenhouse than the field within a crop growing season. Short-term management effect on soil C and N fractions were readily obtained with reduced variability under controlled soil and

  14. Integrating pasture-based livestock production with annual crop production on the Great Plains to reduce loss of grassland wildlife

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tallgrass prairie has been replaced by corn and soybeans and mixed-grass prairie is being replaced by various annual crops. Annual crop fields support vegetarian diets but not much wildlife. Alternatively, integrating pastured livestock farming with annual crops can provide wildlife habitat. For ...

  15. Cover crops influence soil microorganisms and phytoextraction of copper from a moderately contaminated vineyard.

    PubMed

    Mackie, K A; Schmidt, H P; Müller, T; Kandeler, E

    2014-12-01

    We investigated the ability of summer (Avena sativa [oat], Trifolium incarnatum [crimson clover], Chenopodium [goosefoot]) and winter (Vicia villosa [hairy vetch], Secale Cereale L. [Rye], Brassica napus L. partim [rape]) cover crops, including a mixed species treatment, to extract copper from an organic vineyard soil in situ and the microbial communities that may support it. Clover had the highest copper content (14.3mgCukg(-1) DM). However, it was the amount of total biomass production that determined which species was most effective at overall copper removal per hectare. The winter crop rye produced significantly higher amounts of biomass (3532kgDMha(-1)) and, therefore, removed significantly higher amounts of copper (14,920mgCuha(-1)), despite less accumulation of copper in plant shoots. The maximum annual removal rate, a summation of best performing summer and winter crops, would be 0.033kgCuha(-1)y(-1). Due to this low annual extraction efficiency, which is less than the 6kgCuha(-1)y(-1) permitted for application, phytoextraction cannot be recommended as a general method of copper extraction from vineyards. Copper concentration did not influence aboveground or belowground properties, as indicated by sampling at two distances from the grapevine row with different soil copper concentrations. Soil microorganisms may have become tolerant to the copper levels at this site. Microbial biomass and soil enzyme activities (arylsulfatase and phosphatase) were instead driven by seasonal fluxes of resource pools. Gram+ bacteria were associated with high soil moisture, while fungi seemed to be driven by extractable carbon, which was linked to high plant biomass. There was no microbial group associated with the increased phytoextraction of copper. Moreover, treatment did not influence the abundance, activity or community structure of soil microorganisms.

  16. Tillage, cropping sequence, and nitrogen fertilization effects on dryland soil carbon dioxide emission and carbon content.

    PubMed

    Sainju, Upendra M; Jabro, Jalal D; Caesar-Tonthat, Thecan

    2010-01-01

    Management practices are needed to reduce dryland soil CO(2) emissions and to increase C sequestration. We evaluated the effects of tillage and cropping sequence combinations and N fertilization on dryland crop biomass (stems + leaves) and soil surface CO(2) flux and C content (0- to 120-cm depth) in a Williams loam from May to October, 2006 to 2008, in eastern Montana. Treatments were no-tilled continuous malt barley (Hordeum vulgaris L.) (NTCB), no-tilled malt barley-pea (Pisum sativum L.) (NTB-P), no-tilled malt barley-fallow (NTB-F), and conventional-tilled malt barley-fallow (CTB-F), each with 0 and 80 kg N ha(-1). Measurements were made both in Phase I (malt barley in NTCB, pea in NTB-P, and fallow in NTB-F and CTB-F) and Phase II (malt barley in all sequences) of each cropping sequence in every year. Crop biomass varied among years, was greater in the barley than in the pea phase of the NTB-P treatment, and greater in NTCB and NTB-P than in NTB-F and CTB-F in 2 out of 3 yr. Similarly, biomass was greater with 80 than with 0 kg N ha(-1) in 1 out of 3 yr. Soil CO(2) flux increased from 8 mg C m(-2) h(-1) in early May to 239 mg C m(-2) h(-1) in mid-June as temperature increased and then declined to 3 mg C m(-2) h(-1) in September-October. Fluxes peaked immediately following substantial precipitation (>10 mm), especially in NTCB and NTB-P. Cumulative CO(2) flux from May to October was greater in 2006 and 2007 than in 2008, greater in cropping than in fallow phases, and greater in NTCB than in NTB-F. Tillage did not influence crop biomass and CO(2) flux but N fertilization had a variable effect on the flux in 2008. Similarly, soil total C content was not influenced by treatments. Annual cropping increased CO(2) flux compared with crop-fallow probably by increasing crop residue returns to soils and root and rhizosphere respiration. Inclusion of peas in the rotation with malt barley in the no-till system, which have been known to reduce N fertilization rates and

  17. Soil phosphorus changes impacted by potato cropping management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Potato crops generally require high amounts of phosphorus (P) fertilizer to reach economically acceptable yields as the low root density of potato plants makes mobilization and acquisition of phosphate a key factor in potato plant growth. In this work, we evaluated soil P changes in 10 potato fields...

  18. Aminopyralid soil residues affect rotational vegetable crops in Florida

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Field experiments were conducted to determine the sensitivity of bell pepper, eggplant, tomato, muskmelon, and watermelon to aminopyralid soil residues. Aminopyralid was applied at six rates ranging from 0.0014 kg ae ha 1 to 0.0448 kg ae ha 1, and vegetable crops were planted in the treated areas. ...

  19. Matrices to Revise Crop, Soil, and Environmental Sciences Undergraduate Curricula

    ERIC Educational Resources Information Center

    Savin, Mary C.; Longer, David; Miller, David M.

    2005-01-01

    Undergraduate curricula for natural resource and agronomic programs have been introduced and revised during the past several decades with a desire to stay current with emerging issues and technologies relevant to constituents. For the past decade, the Department of Crop, Soil, and Environmental Sciences (CSES) faculty at the University of Arkansas…

  20. Soil surface carbon dioxide efflux of bioenergy cropping systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  1. Maximum soil organic carbon storage in Midwest U.S. cropping systems when crops are optimally nitrogen-fertilized

    PubMed Central

    Barker, Daniel W.; Helmers, Matthew J.; Miguez, Fernando E.; Olk, Daniel C.; Sawyer, John E.; Six, Johan; Castellano, Michael J.

    2017-01-01

    Nitrogen fertilization is critical to optimize short-term crop yield, but its long-term effect on soil organic C (SOC) is uncertain. Here, we clarify the impact of N fertilization on SOC in typical maize-based (Zea mays L.) Midwest U.S. cropping systems by accounting for site-to-site variability in maize yield response to N fertilization. Within continuous maize and maize-soybean [Glycine max (L.) Merr.] systems at four Iowa locations, we evaluated changes in surface SOC over 14 to 16 years across a range of N fertilizer rates empirically determined to be insufficient, optimum, or excessive for maximum maize yield. Soil organic C balances were negative where no N was applied but neutral (maize-soybean) or positive (continuous maize) at the agronomic optimum N rate (AONR). For continuous maize, the rate of SOC storage increased with increasing N rate, reaching a maximum at the AONR and decreasing above the AONR. Greater SOC storage in the optimally fertilized continuous maize system than in the optimally fertilized maize-soybean system was attributed to greater crop residue production and greater SOC storage efficiency in the continuous maize system. Mean annual crop residue production at the AONR was 22% greater in the continuous maize system than in the maize-soybean system and the rate of SOC storage per unit residue C input was 58% greater in the monocrop system. Our results demonstrate that agronomic optimum N fertilization is critical to maintain or increase SOC of Midwest U.S. cropland. PMID:28249014

  2. Maximum soil organic carbon storage in Midwest U.S. cropping systems when crops are optimally nitrogen-fertilized.

    PubMed

    Poffenbarger, Hanna J; Barker, Daniel W; Helmers, Matthew J; Miguez, Fernando E; Olk, Daniel C; Sawyer, John E; Six, Johan; Castellano, Michael J

    2017-01-01

    Nitrogen fertilization is critical to optimize short-term crop yield, but its long-term effect on soil organic C (SOC) is uncertain. Here, we clarify the impact of N fertilization on SOC in typical maize-based (Zea mays L.) Midwest U.S. cropping systems by accounting for site-to-site variability in maize yield response to N fertilization. Within continuous maize and maize-soybean [Glycine max (L.) Merr.] systems at four Iowa locations, we evaluated changes in surface SOC over 14 to 16 years across a range of N fertilizer rates empirically determined to be insufficient, optimum, or excessive for maximum maize yield. Soil organic C balances were negative where no N was applied but neutral (maize-soybean) or positive (continuous maize) at the agronomic optimum N rate (AONR). For continuous maize, the rate of SOC storage increased with increasing N rate, reaching a maximum at the AONR and decreasing above the AONR. Greater SOC storage in the optimally fertilized continuous maize system than in the optimally fertilized maize-soybean system was attributed to greater crop residue production and greater SOC storage efficiency in the continuous maize system. Mean annual crop residue production at the AONR was 22% greater in the continuous maize system than in the maize-soybean system and the rate of SOC storage per unit residue C input was 58% greater in the monocrop system. Our results demonstrate that agronomic optimum N fertilization is critical to maintain or increase SOC of Midwest U.S. cropland.

  3. Digital Mapping of Soil Salinity and Crop Yield across a Coastal Agricultural Landscape Using Repeated Electromagnetic Induction (EMI) Surveys.

    PubMed

    Yao, Rongjiang; Yang, Jingsong; Wu, Danhua; Xie, Wenping; Gao, Peng; Jin, Wenhui

    2016-01-01

    Reliable and real-time information on soil and crop properties is important for the development of management practices in accordance with the requirements of a specific soil and crop within individual field units. This is particularly the case in salt-affected agricultural landscape where managing the spatial variability of soil salinity is essential to minimize salinization and maximize crop output. The primary objectives were to use linear mixed-effects model for soil salinity and crop yield calibration with horizontal and vertical electromagnetic induction (EMI) measurements as ancillary data, to characterize the spatial distribution of soil salinity and crop yield and to verify the accuracy of spatial estimation. Horizontal and vertical EMI (type EM38) measurements at 252 locations were made during each survey, and root zone soil samples and crop samples at 64 sampling sites were collected. This work was periodically conducted on eight dates from June 2012 to May 2013 in a coastal salt-affected mud farmland. Multiple linear regression (MLR) and restricted maximum likelihood (REML) were applied to calibrate root zone soil salinity (ECe) and crop annual output (CAO) using ancillary data, and spatial distribution of soil ECe and CAO was generated using digital soil mapping (DSM) and the precision of spatial estimation was examined using the collected meteorological and groundwater data. Results indicated that a reduced model with EMh as a predictor was satisfactory for root zone ECe calibration, whereas a full model with both EMh and EMv as predictors met the requirement of CAO calibration. The obtained distribution maps of ECe showed consistency with those of EMI measurements at the corresponding time, and the spatial distribution of CAO generated from ancillary data showed agreement with that derived from raw crop data. Statistics of jackknifing procedure confirmed that the spatial estimation of ECe and CAO exhibited reliability and high accuracy. A general

  4. Digital Mapping of Soil Salinity and Crop Yield across a Coastal Agricultural Landscape Using Repeated Electromagnetic Induction (EMI) Surveys

    PubMed Central

    Yao, Rongjiang; Yang, Jingsong; Wu, Danhua; Xie, Wenping; Gao, Peng; Jin, Wenhui

    2016-01-01

    Reliable and real-time information on soil and crop properties is important for the development of management practices in accordance with the requirements of a specific soil and crop within individual field units. This is particularly the case in salt-affected agricultural landscape where managing the spatial variability of soil salinity is essential to minimize salinization and maximize crop output. The primary objectives were to use linear mixed-effects model for soil salinity and crop yield calibration with horizontal and vertical electromagnetic induction (EMI) measurements as ancillary data, to characterize the spatial distribution of soil salinity and crop yield and to verify the accuracy of spatial estimation. Horizontal and vertical EMI (type EM38) measurements at 252 locations were made during each survey, and root zone soil samples and crop samples at 64 sampling sites were collected. This work was periodically conducted on eight dates from June 2012 to May 2013 in a coastal salt-affected mud farmland. Multiple linear regression (MLR) and restricted maximum likelihood (REML) were applied to calibrate root zone soil salinity (ECe) and crop annual output (CAO) using ancillary data, and spatial distribution of soil ECe and CAO was generated using digital soil mapping (DSM) and the precision of spatial estimation was examined using the collected meteorological and groundwater data. Results indicated that a reduced model with EMh as a predictor was satisfactory for root zone ECe calibration, whereas a full model with both EMh and EMv as predictors met the requirement of CAO calibration. The obtained distribution maps of ECe showed consistency with those of EMI measurements at the corresponding time, and the spatial distribution of CAO generated from ancillary data showed agreement with that derived from raw crop data. Statistics of jackknifing procedure confirmed that the spatial estimation of ECe and CAO exhibited reliability and high accuracy. A general

  5. Spectral properties of agricultural crops and soils measured from space, aerial, field, and laboratory sensors

    NASA Technical Reports Server (NTRS)

    Bauer, M. E. (Principal Investigator); Vanderbilt, V. C.; Robinson, B. F.; Daughtry, C. S. T.

    1981-01-01

    Investigations of the multispectral reflectance characteristics of crops and soils as measured from laboratory, field, aerial, and satellite sensor systems are reviewed. The relationships of important biological and physical characteristics to the spectral properties of crops and soils are addressed.

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

    NASA Astrophysics Data System (ADS)

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

    2013-04-01

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

  7. Remote sensing of agricultural crops and soils

    NASA Technical Reports Server (NTRS)

    Bauer, M. E. (Principal Investigator)

    1982-01-01

    Research results and accomplishments of sixteen tasks in the following areas are described: (1) corn and soybean scene radiation research; (2) soil moisture research; (3) sampling and aggregation research; (4) pattern recognition and image registration research; and (5) computer and data base services.

  8. Using stable isotopes to characterize differential depth of water uptake based on environmental conditions in perennial biofuel and traditional annual crops

    NASA Astrophysics Data System (ADS)

    Miller, J. N.; Nystrom, R.; Bernacchi, C.

    2013-12-01

    Global climate change related to fossil fuel consumption coupled with the necessity for secure, cost-effective, and renewable domestic energy is continuing to drive the development of a bioenergy industry. Numerous second-generation biofuel crops have been identified that hold promise as sustainable feedstocks for the industry, including perennial grasses that utilize the highly water and energy efficient C4 photosynthetic pathway. Among the perennial grasses, miscanthus (Miscanthus × giganteus) and switchgrass (Panicum virgatum) stand out as having high biomass, minimal maintenance, low nutrient input requirements, and positive environmental benefits. These grasses are able to withstand a wide range of growing season temperatures and precipitation regimes, particularly in reference to the annual row crops that they are likely to replace. During the drought of 2012 traditional row crops suffered major reductions in yield whereas the perennial grasses retained relatively high biomass yields. We hypothesize that this is due to the ability of the perennial grasses to access water from deeper soil water relative to the annual row crops. To test this hypothesis, we use isotopic techniques to determine the soil depth from which the various species obtain water. Data from summer 2013 suggests that the perennial grasses preferentially use surface water when available but can extract water from depths that the annual row crops are unable to reach. These results indicate that perennial grasses, with deeper roots, will likely sustain growth under conditions when annual row crops are unable.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  10. Effects of soil composition and mineralogy on remote sensing of crop residue cover

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The management of crop residues in agricultural fields influences soil erosion and soil carbon sequestration. Remote sensing methods can efficiently assess crop residue cover and tillaje intensity over many fields in a region. Although the reflectance spectra of soils and crop residues are often s...

  11. 7 CFR 205.203 - Soil fertility and crop nutrient management practice standard.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... nutrients and soil fertility through rotations, cover crops, and the application of plant and animal... 7 Agriculture 3 2012-01-01 2012-01-01 false Soil fertility and crop nutrient management practice... Requirements § 205.203 Soil fertility and crop nutrient management practice standard. (a) The producer...

  12. 7 CFR 205.203 - Soil fertility and crop nutrient management practice standard.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... nutrients and soil fertility through rotations, cover crops, and the application of plant and animal... 7 Agriculture 3 2011-01-01 2011-01-01 false Soil fertility and crop nutrient management practice... Requirements § 205.203 Soil fertility and crop nutrient management practice standard. (a) The producer...

  13. 7 CFR 205.203 - Soil fertility and crop nutrient management practice standard.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... nutrients and soil fertility through rotations, cover crops, and the application of plant and animal... 7 Agriculture 3 2014-01-01 2014-01-01 false Soil fertility and crop nutrient management practice... Requirements § 205.203 Soil fertility and crop nutrient management practice standard. (a) The producer...

  14. 7 CFR 205.203 - Soil fertility and crop nutrient management practice standard.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... nutrients and soil fertility through rotations, cover crops, and the application of plant and animal... 7 Agriculture 3 2013-01-01 2013-01-01 false Soil fertility and crop nutrient management practice... Requirements § 205.203 Soil fertility and crop nutrient management practice standard. (a) The producer...

  15. 7 CFR 205.203 - Soil fertility and crop nutrient management practice standard.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

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

  16. Rye cover crop effects on soil quality in no-till corn silage-soybean cropping systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn and soybean farmers in the upper Midwest are showing increasing interest in winter cover crops. Known benefits of winter cover crops include reductions in nutrient leaching, erosion prevention, and weed suppression; however, the effects of winter cover crops on soil quality in this region have ...

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

    NASA Astrophysics Data System (ADS)

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

    2016-10-01

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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  20. Threshold dynamics in soil carbon storage for bioenergy crops.

    PubMed

    Woo, Dong K; Quijano, Juan C; Kumar, Praveen; Chaoka, Sayo; Bernacchi, Carl J

    2014-10-21

    Because of increasing demands for bioenergy, a considerable amount of land in the midwestern United States could be devoted to the cultivation of second-generation bioenergy crops, such as switchgrass and miscanthus. The foliar carbon/nitrogen ratio (C/N) in these bioenergy crops at harvest is significantly higher than the ratios in replaced crops, such as corn or soybean. We show that there is a critical soil organic matter C/N ratio, where microbial biomass can be impaired as microorganisms become dependent upon net immobilization. The simulation results show that there is a threshold effect in the amount of aboveground litter input in the soil after harvest that will reach a critical organic matter C/N ratio in the soil, triggering a reduction of the soil microbial population, with significant consequences in other microbe-related processes, such as decomposition and mineralization. These thresholds are approximately 25 and 15% of aboveground biomass for switchgrass and miscanthus, respectively. These results suggest that values above these thresholds could result in a significant reduction of decomposition and mineralization, which, in turn, would enhance the sequestration of atmospheric carbon dioxide in the topsoil and reduce inorganic nitrogen losses when compared to a corn-corn-soybean rotation.

  1. Litter Inputs and Soil Aggregation in Midwestern Biofuel Crops

    NASA Astrophysics Data System (ADS)

    Kantola, I. B.; Masters, M. D.; Smyth, E. M.; DeLucia, E. H.

    2014-12-01

    Perennial C4 grasses represent alternatives to corn for the production of ethanol because of low management costs and high biomass production. To evaluate the effects of perennial grasses on the agricultural soils of the Midwest, native switchgrass and a sterile hybrid of the Asian grass Miscanthus were planted at the University of Illinois Energy Farm in 2008. Through five years of growth, above and belowground plant biomass, litter, and soil were compared with soils in plots growing a corn-corn-soy rotation typical of the area. Above- and belowground plant biomass in Miscanthus and switchgrass averaged higher than corn/soy following two years of perennial establishment, with belowground biomass exceeding corn/soy by approximately 5-fold in the year after establishment (2010) and 25-fold by 2012. Measurements of root distribution and turnover rates indicate that roots are the primary contribution of new carbon to soils under perennial crops. Physical fractionation of the soils into water stable aggregates showed 4-14% increases in macroaggregate fractions under perennial crops; the large aggregates are adhered together by organic material and indicative of the increased presence of labile carbon forms like plant roots, fungi, and plant and microbial exudates. Carbon and nitrogen analyses of the fractions show that while overall carbon has not increased significantly in whole soil, soils under perennial grasses are concentrating carbon by 5-17% in the macroaggregates after just 5 years. Native switchgrass roots (buried) and litter (surface-applied) decompose faster than Miscanthus roots and litter, but slower than corn roots and litter buried to simulate incorporation by tillage. Switchgrass soil shows the highest degree of macroaggregate formation, pointing to a high rate of litter and root decomposition and incorporation into soil structure. While macroaggregates are relatively labile soil structures compared to microaggregates and free silt and clay, they offer

  2. [Effect of long-term fertilization on crop yield and soil fertility of upland red soil].

    PubMed

    Kong, Hongmin; He, Yuanqiu; Wu, Dafu; Li, Chengliang

    2004-05-01

    The studies on the influence of long-term fertilization on crop yield and soil fertility of upland red soil showed that P was the most deficient in this soil, and hence, phosphorus fertilizer had the best effect on crop yield. Applying lime and microelements could not significantly increase the crop yield. The concentration of P and K in peanut could be increased if fertilizer was applied, indicating that the supply level of soil nutrients decided the nutrient concentration in plants. The reconstructive efficiency of soil available nutrient pool was dependent on the surplus or deficit of soil nutrients. When the surplus of nutrients was 1 kg x hm(-2), N was increased by 0.6-6.2 mg x kg(-1), P was increased by 0.20-0.28 mg x kg(-1), and K was increased by 1.1-8.5 mg x kg(-1). The changing in results was due to the loss of N and K from soil. The nutrient bupplying capability of soil was the quantity of the nutrients which soil could provide by weathering to satisfy the plant growth. The amount of P fixed by soil was 43.5 kg x hm(-2) x yr(-1), and that of N and K provided by soil was 40.5 and 55 x kg x hm(-2) x yr(-1), respectively.

  3. Eight Years of Annual No-Till Cropping in Washington's Winter Wheat- Summer Fallow Region

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The tillage-based winter wheat – summer fallow (WW-SF) cropping system has dominated dryland farming in the Pacific Northwest for 125 years. We conducted a large-scale multidisciplinary 8-year study of annual no-till cropping systems as an alternative to WW-SF. Soft white and hard white classes of w...

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

    PubMed

    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.

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

    PubMed Central

    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. PMID:26192436

  6. Replacing fallow with cover crops in a semiarid soil:Effects on soil properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Replacement of fallow in crop–fallow systems with cover crops (CCs) may improve soil properties. We assessed whether replacing fallow in no-till winter wheat (Triticum aestivum L.)–fallow with winter and spring CCs for 5 years reduced wind and water erosion, increased soil organic carbon (SOC), and ...

  7. Soil Erosion: Advanced Crop and Soil Science. A Course of Study.

    ERIC Educational Resources Information Center

    Miller, Larry E.

    The course of study represents the last of six modules in advanced crop and soil science and introduces the agriculture student to the topic of soil erosion. Upon completion of the two day lesson, the student will be able to: (1) define conservation, (2) understand how erosion takes place, and (3) list ways of controlling wind and water erosion.…

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

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

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

  9. Impact of rapeseed cropping on the soil carbon balance

    NASA Astrophysics Data System (ADS)

    Moffat, Antje Maria; Herbst, Mathias; Huth, Vytas; Andres, Monique; Augustin, Jürgen

    2015-04-01

    Winter oilseed rape is the dominant biofuel crop in the young moraine landscape in Northern Germany. Since the cultivation of biofuel crops requires sustainability compared to fossil fuels by law, detailed knowledge about their green house gas (GHG) balance is necessary. The soil carbon balance is one of the key contributors to the total GHG balance and also very important for the assessment of soil fertility. However, the knowledge about the impact of different management practices on the soil carbon balance is very limited up to now. Therefore, we investigated the carbon fluxes of winter oilseed rape at field plots near Dedelow/Uckermark in NE Germany with different treatments of fertilization (mineral versus organic) and tillage (no-till and mulch-till versus ploughing). The dynamics of the carbon fluxes are mainly driven by the current climatic conditions but the overall response depends strongly on the ecosystem state (with its physiological and microbiological properties) which is affected by management. To get the full carbon flux dynamics but also the impact of the different management practices, two different approaches were used: The eddy covariance technique to get continuous fluxes throughout the year and the manual chamber technique to detect flux differences between specific management practices. The manual chamber measurements were conducted four-weekly as all-day campaigns using a flow-through non-steady-state closed chamber system. The fluxes in-between campaigns were gap-filled based on functional relationships with soil and air temperature (for the ecosystem respiration) and photosynthetic active radiation (for the gross primary production). All results presented refer to the cropping season 2012-2013. The combination of the two measurement techniques allows the evaluation of chamber fluxes including an independent estimate of the error on the overall balances. Despite the considerable errors, there are significant differences in the soil carbon

  10. Soil quality differences in a mature alley cropping system in temperate North America

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alley cropping in agroforestry practices has been shown to improve soil quality, however information on long-term effects (>10 years) of alley cropping on soils in the temperate zone is very limited. The objective of this study was to examine effects of management, landscape, and soil depth on soil...

  11. Isotopic Tracer Study of Hydraulic Transfer Between Native Woody Shrubs and Associated Annual Crops Under Dry Conditions in the Sahel

    NASA Astrophysics Data System (ADS)

    Bogie, Nathaniel; Bayala, Roger; Diedhiou, Ibrahima; Fogel, Marilyn; Dick, Richard; Ghezzehei, Teamrat A.

    2015-04-01

    Erratic precipitation at the beginning and end of the rainy season combined with short drought periods during the cropping season pose a major challenge for rain-fed agriculture and food security in the Sahel. Research has shown that intercropping annual crops with native evergreen woody shrubs in Senegal can greatly increase crop productivity. Hydraulic redistribution (HR), or the diurnal rewetting of dry soil by the pathway of the root system that extends into wetter soil has been found in many plants and climates worldwide. The HR pathway could be a factor in Senegal where water provided by shrubs aids crop growth during dry periods but this has not been confirmed. Therefore, the objective was to determine the ability of shrubs to provide water to millet plants using the deuterium tracer. Penisetum glaucum (Pearl Millet) was grown in association with the native woody shrub Guiera senegalensis under drip irrigation until 68 days after sowing, followed by a with holding of water during late flowering and early grain-filling stage. Within 10 days the soils in the stressed plots became extremely dry with water potentials ranging from -0.5 Mpa to -3.0 Mpa at 20cm depth. Twenty days after the initiation of water stress, vials of isotopically enriched deuterium tracer was sealed around cut roots of three separate shrubs at a depth of 1.0 m followed by sampling of aboveground tissue from injection shrubs and closely growing crop plants over a period of five days. Using cryogenic vacuum distillation, plant water samples were extracted from plant tissue. With lab work completed on two replications, a highly enriched deuterium signal was observed in the tissue water of the shrub beginning twelve hours after the injection. In the same replication thirty-six hours after the beginning of injection, a highly enriched pulse of deuterium in the crop growing directly adjacent to the injection shrub was observed. In a concurrent injection to a nearby shrub under much drier

  12. SOIL ECOLOGY AS KEY TO SUSTAINABLE CROP PRODUCTION.

    PubMed

    De Deyn, G B

    2015-01-01

    Sustainable production of food, feed and fiberwarrants sustainable soil management and crop protection. The tools available to achieve this are both in the realm of the plants and of the soil, with a key role for plant-soil interactions. At the plant level we have vast knowledge of variation within plant species with respect to pests and diseases, based on which we can breed for resistance. However, given that systems evolve this resistance is bound to be temporarily, hence also other strategies are needed. Here I plea for an integrative approach for sustainable production using ecological principles. Ecology, the study of how organisms interact with their environment, teaches us that diversity promotes productivity and yield stability. These effects are thought to be governed through resource use complementarity and reduced build-up of pests and diseases both above- and belowground. In recent years especially the role of soil biotic interactions has revealed new insights in how plant diversity and productivity are related to soil biodiversity and the functions soil biota govern. In our grassland biodiversity studies we found that root feeders can promote plant diversity and succession without reducing plant community productivity, this illustrates the role of diversity to maintain productivity. Also diversity within species offers scope for sustainable production, for example through awareness of differences between plant genotypes in chemical defense compounds that can attract natural enemies of pests aboveground- and belowground thereby providing plant protection. Plant breeding can also benefit from using complementarity between plant species in the selection for new varieties, as our work demonstrated that when growing in species mixtures plant species adapt to each other over time such that their resource acquisition traits become more complementing. Finally, in a recent meta-analysis we show that earthworms can stimulate crop yield with on average 25%, but

  13. Effect of different crops on soil organic matter and biological activity in Oxisols under three different crops

    NASA Astrophysics Data System (ADS)

    Toledo, Diana Marcela; Arzuaga, Silvia; Dalurzo, Humberto; Zornoza, Raúl; Vazquez, Sara

    2015-04-01

    The objective of this work was to evaluate changes in soil organic matter in Oxisols under different crops compared to native rainforest, and to assess if acid phosphatase activity (APA) could be a good indicator for SOC changes and soil quality. The experimental design consisted of four completely randomized blocks with four treatments: subtropical rainforest (F); yerba mate crop (I) (Ilex paraguariensis SH.); citrus crop (C) (Citrus unshiu Marc); and tobacco crop (T) (Nicotiana tabacum L.). Soil samples were taken at 0-10; 10-20 and 20-30 cm depths. The variables measured were soil organic carbon (SOC), APA, clay content, pH, total nitrogen (Nt), available phosphorus (P) and CO2 emissions. All data were analyzed by ANOVA to assess the effects of land-use changes. The treatment means were compared through Duncan's multiple range tests (p<0.05). The relationship between variables was determined with a simple correlation analysis and with a multiple linear regression analysis through the stepwise method. These soils showed an acid reaction and their clay content was over 650 g kg-1 for the three depths. SOC and N contents were higher in native soils, intermediate for the citrus crop, and lower under both tobacco and yerba mate crops. CO2 emissions were higher in the rainforest (47.32 kg ha-1 of CO2) than in cultivated soils, which indicates that biological activity is enhanced in rainforest soils where substrates for soil biota and fauna are more readily available. The variability of 76% in APA was explained by total nitrogen, which is closely related to soil organic matter, and by available P. Conversion of subtropical rainforests into agricultural lands reduced SOC content and acid phosphatase activity, thereby lowering soil quality. In this study, acid phosphatase activity proved to be a sensitive indicator to detect changes from pristine to cropped soils, but it failed to distinguish differences among crop systems.

  14. Effects of agricultural practices of three crops on the soil communities under Mediterranean conditions: field evaluation.

    NASA Astrophysics Data System (ADS)

    Leitão, Sara; José Cerejeira, Maria; Abreu, Manuela; Sousa, José Paulo

    2014-05-01

    Sustainable agricultural production relies on soil communities as the main actors in key soil processes necessary to maintain sustainable soil functioning. Soil biodiversity influences soil physical and chemical characteristics and thus the sustainability of crop and agro-ecosystems functioning. Agricultural practices (e.g.: soil tillage, pesticides and fertilizer applications, irrigation) may affects negatively or positively soil biodiversity and abundances by modifying the relationships between organisms in the soil ecosystem. The present study aimed to study the influence of agricultural practices of three crops (potato, onion and maize) under Mediterranean climate conditions on soil macro- and mesofauna during their entire crop cycles. Effects on soil communities were assessed at a higher tier of environmental risk assessment comprising field testing of indigenous edaphic communities in a selected study-site located in a major agriculture region of Central Portugal, Ribatejo e Oeste, neighbouring protected wetlands. A reference site near the agricultural field site was selected as a Control site to compare the terrestrial communities' composition and variation along the crop cycle. The field soil and Control site soil are sandy loam soils. Crops irrigation was performed by center-pivot (automated sprinkler that rotates in a half a circle area) and by sprinklers. Soil macro- and mesofauna were collected at both sites (field and Control) using two methodologies through pitfall trapping and soil sampling. The community of soil macro- and mesofauna of the three crops field varied versus control site along the crops cycles. Main differences were due to arachnids, coleopterans, ants and adult Diptera presence and abundance. The feeding activity of soil fauna between control site and crop areas varied only for potato and onion crops vs. control site but not among crops. Concentration of pesticides residues in soil did not cause apparent negative effects on the soil

  15. Chemical Features of Soil: Advanced Crop and Soil Science. A Course of Study.

    ERIC Educational Resources Information Center

    Miller, Larry E.

    The course of study represents the fifth of six modules in advanced crop and soil science and introduces the agriculture student to chemical features of the soil. Upon completing the four day lesson, the student will be able to: (1) list macro- and micro-nutrients, (2) define pH and its effect on plants, (3) outline Cation Exchange of the soil,…

  16. Annual Medicago: From a Model Crop Challenged by a Spectrum of Necrotrophic Pathogens to a Model Plant to Explore the Nature of Disease Resistance

    PubMed Central

    TIVOLI, B.; BARANGER, A.; SIVASITHAMPARAM, K.; BARBETTI, M. J.

    2006-01-01

    • Background Annual Medicago spp., including M. truncatula, play an important agronomic role in dryland farming regions of the world where they are often an integral component of cropping systems, particularly in regions with a Mediterranean or Mediterranean-type climate where they grow as winter annuals that provide both nitrogen and disease breaks for rotational crops. Necrotrophic foliar and soil-borne pathogens dominate these regions and challenge the productivity of annual Medicago and crop legume species. • Scope This review outlines some of the major and/or widespread diseases these necrotrophic pathogens cause on Medicago spp. It then explores the potential for using the spectrum of necrotrophic pathogen–host interactions, with annual Medicago as the host plant, to better understand and model pathosystems within the diseases caused by nectrotrophic pathogens across forage and grain legume crops. • Conclusions Host resistance clearly offers the best strategy for cost-effective, long-term control of necrotrophic foliar and soil-borne pathogens, particularly as useful resistance to a number of these diseases has been identified. Recently and initially, the annual M. truncatula has emerged as a more appropriate and agronomically relevant substitute to Arabidopsis thaliana as a model plant for legumes, and is proving an excellent model to understand the mechanisms of resistance both to individual pathogens and more generally to most forage and grain legume necrotrophic pathogens. PMID:16803846

  17. Annual crop type classification of the U.S. Great Plains for 2000 to 2011

    USGS Publications Warehouse

    Howard, Daniel M.; Wylie, Bruce K.

    2014-01-01

    The purpose of this study was to increase the spatial and temporal availability of crop classification data. In this study, nearly 16.2 million crop observation points were used in the training of the US Great Plains classification tree crop type model (CTM). Each observation point was further defined by weekly Normalized Difference Vegetation Index, annual climate, and a number of other biogeophysical environmental characteristics. This study accounted for the most prevalent crop types in the region, including, corn, soybeans, winter wheat, spring wheat, cotton, sorghum, and alfalfa. Annual CTM crop maps of the US Great Plains were created for 2000 to 2011 at a spatial resolution of 250 meters. The CTM achieved an 87 percent classification success rate on 1.8 million observation points that were withheld from model training. Product validation was performed on greater than 15,000 county records with a coefficient of determination of R2 = 0.76.

  18. Combining cropland data layers to identify alfalfa-annual crop rotation patterns and opportunities

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa (Medicago sativa L.) can provide many economic and environmental benefits to crop rotations. Our objectives were to quantify alfalfa stand lengths, identify the two crops following alfalfa, and determine the soil and temporal factors affecting them. The USDA-NASS cropland data layers for 200...

  19. Response of soil respiration to climate across biofuel crops and land use histories

    NASA Astrophysics Data System (ADS)

    Su, Y.; Chen, J.; Shao, C.; Shen, W.; Zenone, T.; John, R.; Deal, M.; Hamilton, S. K.; Robertson, G. P.

    2013-12-01

    treatment decreased 2.25% and 8.55%, respectively, in mid-summer between 2011 and 2012), SRRs were also comparatively low (average SRRt and SRRh decreased 5.57 and 3.12 umol CO2/m2s, respectively, in 2012). Besides, substrate supply importantly regulates SRRs; the patterns of SRR coincide that of crop growth through a growing season. SRRs of annual plan (corn) sites have very narrow peaks while SRRs of perennial crops (all of the rest crops in the experiment) have extended periods of highest SRRs. This may be a consequence of the difference between the phenology of annual and perennial crops. Generally, SRRh are lower than SRRt at all AG and reference sites (the difference between SRRh and SRRt are 5.23, 2.32, 3.87 and 6.03 at AG-Cr, AG-Sw, AG-Pr and reference site, respectively) in mid-summer in 2011, however, the difference between SRRh and SRRt are close at CRP sites (the difference are 1.42, 1.87 and -0.07 at CRP-Cr, CRP-Sw and CRP-Pr site). Large amount of carbon released into soil due to land use change at CRP sites would lead to high SRRh.

  20. Physical effects of soil drying on roots and crop growth.

    PubMed

    Whitmore, Andrew P; Whalley, W Richard

    2009-01-01

    The nature and effect of the stresses on root growth in crops subject to drying is reviewed. Drought is a complex stress, impacting on plant growth in a number of interacting ways. In response, there are a number of ways in which the growing plant is able to adapt to or alleviate these stresses. It is suggested that the most significant opportunity for progress in overcoming drought stress and increasing crop yields is to understand and exploit the conditions in soil by which plant roots are able to maximize their use of resources. This may not be straightforward, with multiple stresses, sometimes competing functions of roots, and conditions which impact upon roots very differently depending upon what soil, what depth or what stage of growth the root is at. Several processes and the interaction between these processes in soil have been neglected. It is our view that drought is not a single, simple stress and that agronomic practice which seeks to adapt to climate change must take account of the multiple facets of both the stress induced by insufficient water as well as other interacting stresses such as heat, disease, soil strength, low nutrient status, and even hypoxia. The potential for adaptation is probably large, however. The possible changes in stress as a result of the climate change expected under UK conditions are assessed and it appears possible that wet warm winters will impact on root growth as much if not more than dry warm summers.

  1. [Effects of transgenic Bt crops on non-target soil animals].

    PubMed

    Yuan, Yi-gang; Ge, Feng

    2010-05-01

    Transgenic Bt crops are widely planted around the world. With the quick development and extension of genetically modified crops, it is needed to make a deep study on the effects of Bt crops on soil ecosystem. This paper reviewed the research progress on the effects of transgenic Bt crops on the population dynamics and community structure of soil animals, e.g., earthworm, nematode, springtail, mite, and beetle, etc. The development history of Bt crops was introduced, the passway the Bt protein comes into soil as well as the residual and degradation of Bt protein in soil were analyzed, and the critical research fields about the ecological risk analysis of transgenic Bt crops on non-target soil animals in the future were approached, which would provide a reference for the research of the effects of transgenic Bt crops on non-target soil animals.

  2. The Relationship Between Carbon Input, Aggregation, and Soil Organic Carbon Stabilization in Sustainable Cropping Systems

    NASA Astrophysics Data System (ADS)

    Kong, A. Y.; Six, J.; Bryant, D. C.; Denison, R.; van Kessel, C.

    2003-12-01

    Approximately 10% of the earth's soil C is stored within agricultural soil ecosystems. Because farming systems hold promise for sequestering C, their sustainability, environmental impact, and potential role in mitigating rising atmospheric CO2 concentrations must be addressed. Our current challenges are to provide credible evidence that agricultural practices can sequester significant amounts of C and to quantify the mechanisms, capacity, and longevity of agricultural lands as C sinks. Agronomic practices that influence yield and, therefore, affect the proportion of crop residues returned to the soil (e.g. cover cropping, irrigation, fertilizer addition, and compost application) are likely to influence soil organic carbon (SOC). The objectives of this study were (1) to determine the influence of C input on C sequestration in SOC fractions and (2) to evaluate how aggregation (MWD) relates to SOC and cumulative C input, across 10 different cropping systems. Using SOM fractionation techniques, soil samples from 10 cropping systems at LTRAS (Long-term Research on Agricultural Systems, Davis, CA) were separated into four aggregate size classes (LM: >2000μ m, sM: 250-2000μ m, m: 53-250μ m, and silt&clay: <53μ m) and into three SOM fractions within LM and sM (cPOM:250-2000μ m, mM: 53-250μ m, and silt&clay: <53μ m). All fractions were analyzed for their C content. Empirically derived relationships between yield and aboveground biomass-C plus yield and belowground biomass-C were used to quantify C input from corn, wheat, and tomato residues as well as for legume cover crops and compost for the different cropping systems. We found a positive correlation between cumulative C input and SOC (R2=0.45, P<0.0001). After 9 years, MWD increased linearly with greater C input (R2=0.64, P<0.0001) and SOC (R2=0.61, P<0.0001), respectively. We observed that aggregate-C shifts from the microaggregate fraction (53-250μ m) in low C input systems to macroaggregate fractions (>2000

  3. Soil properties and crop productivity as influenced by flyash incorporation in soil.

    PubMed

    Kalra, Naveen; Jain, M C; Joshi, H C; Chaudhary, R; Kumar, Sushil; Pathak, H; Sharma, S K; Kumar, Vinod; Kumar, Ravindra; Harit, R C; Khan, S A; Hussain, M Z

    2003-09-01

    Field experiments were carried out during 1996-97 at Gulawathi, Muthiani and Salarpur Villages, IARI Farm, New Delhi and NCPP Campus, Dadri to evaluate changes in soil characteristics and growth of wheat (Triticum aestivum L.), mustard (Brassica juncea L.), lentil (Lence esculenta Moench.), rice (Oryza sativa L.) and maize (Zea mays L.) by varying amounts of flyash addition (up to 50t ha(-1)) in soils at sowing/transplanting time of crops. Flyash addition in areas adjoining NCPP Thermal Power Plant, Dadri, Ghaziabad, U.P. ranged from 5-12 t ha(-1)] yr(-1) in 1995-96. Shoot and root growth and yield of test crops at different locations after flyash incorporation resulted in beneficial effects of flyash addition in most cases. The silt dominant texture of flyash improved loamy sand to sandy loam textures of the surface soils at the farmers' fields. The increased growth in yield of crops with flyash incorporation was possibly due to modifications in soil moisture retention and transmission characteristics, bulk density, physico-chemical characters such as pH and EC and organic carbon content. The response of flyash addition in the soil on soil health and crop productivity needs to be evaluated on long-term sustainable aspects.

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

    PubMed Central

    Schuiteman, Matthew A.; Vos, Ronald J.

    2017-01-01

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

  5. Crop residues as soil amendments and feedstock for bioethanol production.

    PubMed

    Lal, R

    2008-01-01

    Traditional solid fuels account for more than 90% of the energy supply for 3 billion people in developing countries. However, liquid biofuels (e.g., ethanol) are perceived as an important alternative to fossil fuel. Global crop residue production is estimated at about 4 billion Mg for all crops and 3 billion Mg per annum for lignocellulosic residues of cereals. One Mg of corn stover can produce 280L of ethanol, compared with 400L from 1Mg of corn grains; 1Mg of biomass is also equivalent to 18.5GJ of energy. Thus, 3 billion Mg of residues are equivalent to 840 billion L of ethanol or 56x10(9)GJ of energy. However, removal of crop residues exacerbates soil degradation, increases net emission of CO2, and aggravates food insecurity. Increasing the SOC pool by 1 Mg C ha(-1)yr(-1) through residue retention on soil can increase world food grain production by 24-40 million Mg yr(-1), and root/tuber production by 6-11 million Mg yr(-1). Thus, identifying alternate sources of biofuel feedstock (e.g., biofuel plantations, animal waste, municipal sold waste) is a high priority. Establishing biofuel plantations on agriculturally marginal or degraded lands can off-set 3.5-4 Pg Cyr(-1).

  6. The influence of long-term fertilization on cadmium (Cd) accumulation in soil and its uptake by crops.

    PubMed

    Wang, Qingyun; Zhang, Jiabao; Zhao, Bingzi; Xin, Xiuli; Zhang, Congzhi; Zhang, Hailin

    2014-09-01

    Continuous application of organic and inorganic fertilizers can affect soil and food quality with respect to heavy metal concentrations. The risk of cadmium (Cd) contamination in a long-term (over 20 years) experimental field in North China with an annual crop rotation of winter wheat and summer maize was investigated. The long-term experiment had a complete randomized block design with seven fertilizer treatments and four replications. The seven fertilizer treatments were (1) organic compost (OM), (2) half organic compost plus half chemical fertilizer (OM + NPK), (3) NPK fertilizer (NPK), (4-6) chemical fertilizers without one of the major nutrients (NP, PK, and NK), and (7) an unamended control (CK). Soil samples from 0 to 20 cm were collected in 1989, 1999, and 2009 to characterize Cd and other soil properties. During the past 20 years, various extents of Cd accumulation were observed in the soil, and the accumulation was mainly affected by atmospheric dry and wet deposition and fertilization. In 2009, the average Cd concentration in the soil was 148 ± 15 μg kg(-1) and decreased in the order of NPK ≈ OM + NKP ≈ PK > NP ≈ NK > OM ≈ CK. Sequential extraction of Cd showed that the acid-soluble fraction (F1, 32 ± 7 %) and the residual fraction (F4, 31 ± 5 %) were the dominant fractions of Cd in the soil, followed by the reducible fraction (F2, 22 ± 5 %) and oxidizable fraction (F3, 15 ± 6 %). The acid-soluble Cd fraction in the soil and Cd accumulation in the crops increased with soil plant available K. Fraction F3 was increased by soil organic C (SOC) and crop yields, but SOC reduced the uptake of soil Cd by crops. The long-term P fertilization resulted in more Cd buildup in the soil than other treatments, but the uptake of Cd by crops was inhibited by the precipitation of Cd with phosphate in the soil. Although soil Cd was slightly increased over the 20 years of intensive crop production, both soil and grain/kernel Cd concentrations were still

  7. Annual Crop Type Classification of the U.S. Great Plains for 2000 - 2011: An Application of Classification Tree Modeling using Remote Sensing and Ancillary Environmental Data (Invited)

    NASA Astrophysics Data System (ADS)

    Howard, D. M.; Wylie, B. K.

    2013-12-01

    The purpose of this study was to increase spatial and temporal availability of crop classification data using reliable source data that have the potential of being applied on local, regional, national, and global levels. This study implemented classification tree modeling to map annual crop types throughout the U.S. Great Plains from 2000 - 2011. Classification tree modeling has been shown in numerous studies to be an effective tool for developing classification models. In this study, nearly 18 million crop observation points, derived from annual U.S. Department of Agriculture (USDA) National Agriculture Statistics Service (NASS) Cropland Data Layers (CDLs), were used in the training, development, and validation of a classification tree crop type model (CTM). Each observation point was further defined by weekly Normalized Differential Vegetation Index (NDVI) readings, annual climatic conditions, soil conditions, and a number of other biogeophysical environmental characteristics. The CTM accounted for the most prevalent crop types in the area, including, corn, soybeans, winter wheat, spring wheat, cotton, sorghum, and alfalfa. Other crops that did not fit into any of these classes were identified and grouped into a miscellaneous class. An 87% success rate was achieved on the classification of 1.8 million observation points (10% of total observation points) that were withheld from training. The CTM was applied to create annual crop maps of the U.S. Great Plains for 2000 - 2011 at a spatial resolution of 250 meters. Product validation was performed by comparing county acreage derived from the modeled crop maps and county acreage data from the USDA NASS Survey Program for each crop type and each year. Greater than 15,000 county records from 2001 - 2010 were compared with a Pearson's correlation coefficient of r = 0.87.

  8. Evaluation of antibiotic mobility in soil associated with swine-slurry soil amendment under cropping conditions.

    PubMed

    Domínguez, C; Flores, C; Caixach, J; Mita, L; Piña, B; Comas, J; Bayona, J M

    2014-11-01

    Interest in identifying pools of antibacterial-resistance genes has grown over the last decade, with veterinary antibiotics (VAs) receiving particular attention. In this paper, a mesoscale study aimed at evaluating the vertical transport of common VAs-namely, fluoroquinolones, tetracyclines, sulfonamides, and lincosamides in agricultural soil subjected to drip irrigation-was performed under greenhouse conditions. Accordingly, leachates of cropped and uncropped soil, amended with swine-slurry leading to 19-38 μg kg(-1) (dry mass) antibiotics in the soil, were analyzed over the course of the productive cycle of a lettuce (42 days) with three sampling campaigns (N = 24). High lincomycin (LCM) concentrations (30-39 μg L(-1)) were detected in the leachates collected from the swine-slurry-amended soil. The highest LCM mass recovered in the leachates (30.1 ± 1.63 %) was obtained from cropped experimental units. In addition, the LCM leaching constant and its leaching potential as obtained from the first-order model were higher in the leachates from the cropped experimental units. Lower concentrations of sulfadimethoxine were also detected in leachates and in soil. Enrofloxacin and oxytetracycline occurred only in soil, which is consistent with high soil interaction.

  9. Greenhouse Gas Emissions Increase Following the Termination of a Perennial Legume Phase of an Annual Crop Rotation within the Red River Valley, Manitoba

    NASA Astrophysics Data System (ADS)

    Hanis, K. L.; Tenuta, M.; Amiro, B. D.; Glenn, A. J.; Maas, S.; Gervais, M.

    2013-12-01

    Perennial legume forages may have the potential to increase soil carbon sequestration and decrease nitrous oxide (N2O) emissions to the atmosphere when introduced into annual cropping systems. However, little is known about what short-term effect the return to annual cropping following termination of perennial legume forage would have on carbon dioxide (CO2) and N2O emissions. Furthermore, there are few quantitative measurements about this impact on the Canadian Prairies. A long-term field experiment to continuously measure CO2 and N2O fluxes was established at the Trace Gas Manitoba (TGAS-MAN) Long Term Greenhouse Gas Monitoring Site at Glenlea, Manitoba using the flux gradient micrometeorlogical technique with a tunable diode laser analyzer. The soil is poorly drained clay in the Red River Valley. The field experiment consisted of four 4-hectare plots planted to corn in 2006 and faba bean in 2007. In 2008, grass-alfalfa forage was introduced to two plots (annual - perennial) and grown until 2011 whereas the other two plots (annual) were planted to annual crops: spring wheat, rapeseed, barley and spring wheat in 2008, 2009, 2010 and 2011, respectively. In late September of 2011 the grass-alfalfa forage was killed and in 2012 all four plots were planted with corn. Termination of the grass-alfalfa forage resulted in greater fall CO2 emissions in 2011, greater spring melt CO2 emissions and net annual N2O emissions in 2012 from the annual-perennial plots when compared to the annual plots. Over seven crop years (2006-2012), the annual - perennial system increased carbon uptake by 3.4 Mg C ha-1 and reduced N2O emissions by 3.0 Mg CO2-eq ha-1 compared to the annual system. However after accounting for harvest removals both the annual and annual-perennial systems were net carbon sources of 5.7 and 2.5 Mg C ha-1 and net GHG sources of 38 and 24 Mg CO2-eq ha-1 respectively. We are currently following the long-term impacts of inclusion of perennial forages in an annual

  10. Effects of irrigation on crops and soils with Raft River geothermal water

    SciTech Connect

    Stanley, N.E.; Schmitt, R.C.

    1980-01-01

    The Raft River Irrigation Experiment investigated the suitability of using energy-expended geothermal water for irrigation of selected field-grown crops. Crop and soil behavior on plots sprinkled or surface irrigated with geothermal water was compared to crop and soil behavior on plots receiving water from shallow irrigation wells and the Raft River. In addition, selected crops were produced, using both geothermal irrigation water and special management techniques. Crops irrigated with geothermal water exhibited growth rates, yields, and nutritional values similar to comparison crops. Cereal grains and surface-irrigated forage crops did not exhibit elevated fluoride levels or accumulations of heavy metals. However, forage crops sprinkled with geothermal water did accumulate fluorides, and leaching experiments indicate that new soils receiving geothermal water may experience increased salinity, exchangeable sodium, and decreased permeability. Soil productivity may be maintained by leaching irrigations.

  11. Biofuel cropping system impacts on soil C, microbial communities and N2O emissions

    NASA Astrophysics Data System (ADS)

    McGowan, Andrew R.

    Substitution of cellulosic biofuel in place of gasoline or diesel could reduce greenhouse gas (GHG) emissions from transportation. However, emissions of nitrous oxide (N2O) and changes in soil organic carbon (SOC) could have a large impact on the GHG balance of cellulosic biofuel, thus there is a need to quantify these responses in cellulosic biofuel crops. The objectives of this study were to: (i) measure changes in yield, SOC and microbial communities in potential cellulosic biofuel cropping systems (ii) measure and characterize the temporal variation in N2O emissions from these systems (iii) characterize the yield and N2O response of switchgrass to N fertilizer and to estimate the costs of production. Sweet sorghum, photoperiod-sensitive sorghum, and miscanthus yielded the highest aboveground biomass (20-32 Mg ha-1). The perennial grasses sequestered SOC over 4 yrs, while SOC stocks did not change in the annual crops. Root stocks were 4-8 times higher in the perennial crops, suggesting greater belowground C inputs. Arbuscular mycorrhizal fungi (AMF) abundance and aggregate mean weight diameter were higher in the perennials. No consistent significant differences were found in N2O emissions between crops, though miscanthus tended to have the lowest emissions. Most N2O was emitted during large events of short duration (1-3 days) that occurred after high rainfall events with high soil NO3-. There was a weak relationship between IPCC Tier 1 N2O estimates and measured emissions, and the IPCC method tended to underestimate emissions. The response of N2O to N rate was nonlinear in 2 of 3 years. Fertilizer induced emission factor (EF) increased from 0.7% at 50 kg N ha-1 to 2.6% at 150 kg N ha-1. Switchgrass yields increased with N inputs up to 100-150 kg N ha-1, but the critical N level for maximum yields decreased each year, suggesting N was being applied in excess at higher N rates. Yield-scaled costs of production were minimized at 100 kg N ha-1 ($70.91 Mg-1

  12. Soil-profile distribution of inorganic N during 6 years of integrated crop-livestock management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Excessive accumulation of soil nitrate-N can threaten water and air quality. How integrated crop-livestock systems might influence soil-profile nitrate-N accumulation has not been investigated. Therefore, we determined soil nitrate-N accumulation during 6 years of evaluation of diverse cropping sy...

  13. Dryland Crop Yields and Soil Organic Matter as Influenced by Long-Term Tillage and Cropping Sequence

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Novel management practices are needed to improve the declining dryland crop yields and soil organic matter using conventional farming practices in the northern Great Plains. We evaluated the 21-yr effect of tillage and cropping sequence on dryland grain and biomass (stems + leaves) yields of spring ...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  15. Long-term impacts of cropping systems and landscape positions on grain crop production on claypan soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sustainable grain crop production on vulnerable claypan soils requires improved knowledge of long-term impacts of conservation cropping systems (CS) with reduced inputs. Therefore, effects of CS and landscape positions (LP) on corn (Zea mays L.), soybean [Glycine max (L.) Merr.], and wheat (Triticum...

  16. Long-term impacts of cropping systems and landscape positions on claypan-soil grain crop production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sustainable grain crop production on vulnerable claypan soils requires improved knowledge of long-term impacts of conservation cropping systems (CS) with reduced inputs. Therefore, effects of CS and landscape positions (LP) on corn (Zea mays L.), soybean [Glycine max (L.) Merr.], and wheat (Triticum...

  17. Summer cover crops and soil amendments to improve growth and nutrient uptake of okra

    SciTech Connect

    Wang, Q.R.; Li, Y.C.; Klassen, W.

    2006-04-15

    A pot experiment with summer cover crops and soil amendments was conducted in two consecutive years to elucidate the effects of these cover crops and soil amendments on 'Clemson Spineless 80' okra (Abelmoschus esculentus) yields and biomass production, and the uptake and distribution of soil nutrients and trace elements. The cover crops were sunn hemp (Crotalaria juncea), cowpea (Vigna unguiculata), velvetbean (Mucuna deeringiana), and sorghum sudan-grass (Sorghum bicolor x S. bicolor var. sudanense) with fallow as the control. The organic soil amendments were biosolids (sediment from wastewater plants), N-Viro Soil (a mixture of biosolids and coal ash), coal ash (a combustion by-product from power plants), co-compost (a mixture of 3 biosolids: 7 yard waste), and yard waste compost (mainly from leaves and branches of trees and shrubs, and grass clippings) with a soil-incorporated cover crop as the control. As a subsequent vegetable crop, okra was grown after the cover crops, alone or together with the organic soil amendments, had been incorporated. All of the cover crops, except sorghum sudangrass in 2002-03, significantly improved okra fruit yields and the total biomass production. Both cover crops and soil amendments can substantially improve nutrient uptake and distribution. The results suggest that cover crops and appropriate amounts of soil amendments can be used to improve soil fertility and okra yield without adverse environmental effects or risk of contamination of the fruit. Further field studies will be required to confirm these findings.

  18. Can Impacts of Climate Change and Agricultural Adaptation Strategies Be Accurately Quantified if Crop Models Are Annually Re-Initialized?

    PubMed

    Basso, Bruno; Hyndman, David W; Kendall, Anthony D; Grace, Peter R; Robertson, G Philip

    2015-01-01

    Estimates of climate change impacts on global food production are generally based on statistical or process-based models. Process-based models can provide robust predictions of agricultural yield responses to changing climate and management. However, applications of these models often suffer from bias due to the common practice of re-initializing soil conditions to the same state for each year of the forecast period. If simulations neglect to include year-to-year changes in initial soil conditions and water content related to agronomic management, adaptation and mitigation strategies designed to maintain stable yields under climate change cannot be properly evaluated. We apply a process-based crop system model that avoids re-initialization bias to demonstrate the importance of simulating both year-to-year and cumulative changes in pre-season soil carbon, nutrient, and water availability. Results are contrasted with simulations using annual re-initialization, and differences are striking. We then demonstrate the potential for the most likely adaptation strategy to offset climate change impacts on yields using continuous simulations through the end of the 21st century. Simulations that annually re-initialize pre-season soil carbon and water contents introduce an inappropriate yield bias that obscures the potential for agricultural management to ameliorate the deleterious effects of rising temperatures and greater rainfall variability.

  19. Can Impacts of Climate Change and Agricultural Adaptation Strategies Be Accurately Quantified if Crop Models Are Annually Re-Initialized?

    PubMed Central

    Basso, Bruno; Hyndman, David W.; Kendall, Anthony D.; Grace, Peter R.; Robertson, G. Philip

    2015-01-01

    Estimates of climate change impacts on global food production are generally based on statistical or process-based models. Process-based models can provide robust predictions of agricultural yield responses to changing climate and management. However, applications of these models often suffer from bias due to the common practice of re-initializing soil conditions to the same state for each year of the forecast period. If simulations neglect to include year-to-year changes in initial soil conditions and water content related to agronomic management, adaptation and mitigation strategies designed to maintain stable yields under climate change cannot be properly evaluated. We apply a process-based crop system model that avoids re-initialization bias to demonstrate the importance of simulating both year-to-year and cumulative changes in pre-season soil carbon, nutrient, and water availability. Results are contrasted with simulations using annual re-initialization, and differences are striking. We then demonstrate the potential for the most likely adaptation strategy to offset climate change impacts on yields using continuous simulations through the end of the 21st century. Simulations that annually re-initialize pre-season soil carbon and water contents introduce an inappropriate yield bias that obscures the potential for agricultural management to ameliorate the deleterious effects of rising temperatures and greater rainfall variability. PMID:26043188

  20. Neural network simulation of soil NO3 dynamic under potato crop system

    NASA Astrophysics Data System (ADS)

    Goulet-Fortin, Jérôme; Morais, Anne; Anctil, François; Parent, Léon-Étienne; Bolinder, Martin

    2013-04-01

    Nitrate leaching is a major issue in sandy soils intensively cropped to potato. Modelling could test and improve management practices, particularly as regard to the optimal N application rates. Lack of input data is an important barrier for the application of classical process-based models to predict soil NO3 content (SNOC) and NO3 leaching (NOL). Alternatively, data driven models such as neural networks (NN) could better take into account indicators of spatial soil heterogeneity and plant growth pattern such as the leaf area index (LAI), hence reducing the amount of soil information required. The first objective of this study was to evaluate NN and hybrid models to simulate SNOC in the 0-40 cm soil layer considering inter-annual variations, spatial soil heterogeneity and differential N application rates. The second objective was to evaluate the same methodology to simulate seasonal NOL dynamic at 1 m deep. To this aim, multilayer perceptrons with different combinations of driving meteorological variables, functions of the LAI and state variables of external deterministic models have been trained and evaluated. The state variables from external models were: drainage estimated by the CLASS model and the soil temperature estimated by an ICBM subroutine. Results of SNOC simulations were compared to field data collected between 2004 and 2011 at several experimental plots under potato cropping systems in Québec, Eastern Canada. Results of NOL simulation were compared to data obtained in 2012 from 11 suction lysimeters installed in 2 experimental plots under potato cropping systems in the same region. The most performing model for SNOC simulation was obtained using a 4-input hybrid model composed of 1) cumulative LAI, 2) cumulative drainage, 3) soil temperature and 4) day of year. The most performing model for NOL simulation was obtained using a 5-input NN model composed of 1) N fertilization rate at spring, 2) LAI, 3) cumulative rainfall, 4) the day of year and 5) the

  1. Soil and water quality implications of production of herbaceous and woody energy crops

    SciTech Connect

    Tolbert, V.R.; Lindberg, J.E.; Green, T.H.

    1997-10-01

    Field-scale studies in three physiographic regions of the Tennessee Valley in the Southeastern US are being used to address the environmental effects of producing biomass energy crops on former agricultural lands. Comparison of erosion, surface water quality and quantity, and subsurface movement of water and nutrients from woody crops, switchgrass and agricultural crops began with crop establishment in 1994. Nutrient cycling, soil physical changes, and productivity of the different crops are also being monitored at the three sites.

  2. Soil Water Improvements with the Long Term Use of a Winter Rye Cover Crop

    NASA Astrophysics Data System (ADS)

    Basche, A.; Kaspar, T.; Archontoulis, S.; Jaynes, D. B.; Sauer, T. J.; Parkin, T.; Miguez, F.

    2015-12-01

    The Midwestern United States, a region that produces one-third of maize and one-quarter of soybeans globally, is projected to experience increasing rainfall variability with future climate change. One approach to mitigate climate impacts is to utilize crop and soil management practices that enhance soil water storage, reducing the risks of flooding and runoff as well as drought-induced crop water stress. While some research indicates that a winter cover crop in a maize-soybean rotation increases soil water, producers continue to be concerned that water use by cover crops will reduce water for a following cash crop. We analyzed continuous in-field soil moisture measurements over from 2008-2014 at a Central Iowa research site that has included a winter rye cover crop in a maize-soybean rotation for thirteen years. This period of study included years in the top third of wettest years on record (2008, 2010, 2014) as well as years in the bottom third of driest years (2012, 2013). We found the cover crop treatment to have significantly higher soil water storage from 2012-2014 when compared to the no cover crop treatment and in most years greater soil water content later in the growing season when a cover crop was present. We further found that the winter rye cover crop significantly increased the field capacity water content and plant available water compared to the no cover crop treatment. Finally, in 2012 and 2013, we measured maize and soybean biomass every 2-3 weeks and did not see treatment differences in crop growth, leaf area or nitrogen uptake. Final crop yields were not statistically different between the cover and no cover crop treatment in any of the years of this analysis. This research indicates that the long-term use of a winter rye cover crop can improve soil water dynamics without sacrificing cash crop growth.

  3. Separating soil evaporation and crop transpiration to improve crop water use efficiency

    NASA Astrophysics Data System (ADS)

    Heng, Lee; Nguyen, Long; Gong, Daozhi; Mei, Xurong; Amenzou, Noureddine

    2014-05-01

    A network of a FAO/IAEA Coordinated Research Project (CRP) on "Managing Irrigation Water to Enhance Crop Productivity under Water-Limiting Conditions: A Role for Isotopic Techniques", involving seven countries was implemented from 2007 to 2012, to identify approaches to improve crop water productivity (production per unit of water input) under water-limiting conditions using isotopic and related techniques. This paper presents findings from the two of the studied sites, one in China and another in Morocco, in using both isotopic and conventional techniques to separate soil evaporation (E) and crop transpiration (T) from total water losses in evapotranspiration (ET) for winter wheat grown under different climatic conditions and methods of irrigation management practices. In the North China Plain (NCP), the estimated E/ET of winter wheat by the isotopic method (Keeling plot using delta oxygen-18 (δ18O)) was in agreement with that obtained by conventional methods (eddy covariance and micro-lysimeter). The high correlation between these methods (R2=0.85, n=27) showed that the E from wheat-growing field contributes an average of 30% of water losses for the whole growing season (Nov-June), with higher E percentage (68%) can be expected before elongation stage due to incomplete canopy cover. The results also showed that through deficit irrigation and improved irrigation scheduling, soil E losses could be reduced by 10-30% of the total water loss compared with full irrigation. In Morocco, field Keeling plot isotopic E and T separation study was carried out for two days in spring of 2012 at Sidi Rahal. The percentage contribution of T to total ET was approximately 73%. The experimental results obtained from both China and Moroccan sites were used to validate FAO's AquaCrop model for E and T, and for improving irrigation scheduling and agronomic practices. Good correlation (R2=0.83) was obtained between measured (isotopic) and AquaCrop simulated ET from NCP. The measured

  4. Straw return reduces yield-scaled N2O plus NO emissions from annual winter wheat-based cropping systems in the North China Plain.

    PubMed

    Yao, Zhisheng; Yan, Guangxuan; Zheng, Xunhua; Wang, Rui; Liu, Chunyan; Butterbach-Bahl, Klaus

    2017-07-15

    Straw return in combination with synthetic N fertilizer is considered to be beneficial to soil fertility and crop yield. Such practice, however, can considerably modify soil microbial activity and relative C and N availability, both of which are known to regulate soil nitrous oxide (N2O) and nitric oxide (NO) emissions. Minimizing these emissions per unit of crop yield is a prerequisite to minimize the environmental footprint of agricultural production and thus, a policy objective. In our study, we quantified N2O and NO emissions and determined fertilizer-N use efficiencies (NUE) and crop yields of two double-cropping (summer maize/Welsh onion-winter wheat) systems with and without straw incorporation in the North China Plain. Relative to the fertilized treatment without straw amendments, straw incorporation showed a significant inhibitory effect on annual N2O emissions from the maize-wheat system (-31%), but no significant effect was observed for the Welsh onion-wheat system. However, straw return significantly reduced annual NO emissions by >30% for both systems. Meanwhile, straw return in both systems significantly increased the NUE and crop yields by 34-47% and 7-16%, respectively, as compared to the treatment without straw additions. Across the double-cropping systems, annual direct emission factors of N2O, NO and N2O+NO were 0.37-0.57%, 0.08-0.78% and 0.57-1.36%, respectively. Furthermore, a negative relationship between direct emission factors of N2O+NO and crop NUE was observed, highlighting the importance of optimizing NUE for reducing environmental risks of a cropping system. When expressing emissions on a yield basis, straw return significantly reduced annual yield-scaled N2O+NO emissions by 15-42% for both systems. Overall, our results show that the combined application of crop straw and synthetic N fertilizer is a promising N management strategy for maximizing crop yields while mitigating N-trace gas emissions.

  5. Sequence effects among crops on alluvial-derived soil compared with those on glacial till-derived soil in the northern Great Plains, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To implement the dynamic cropping systems concept, agriculturalists need information about how crop species affect following years’ crops. Little research exists about how soil type affects crop sequence dynamics. Sandy loam, alluvial soil in North Dakota was the site of a crop sequence experiment u...

  6. Agricultural management practices to sustain crop yields and improve soil and environmental qualities.

    PubMed

    Sainju, Upendra M; Whitehead, Wayne F; Singh, Bharat P

    2003-08-20

    In the past several decades, agricultural management practices consisting of intensive tillage and high rate of fertilization to improve crop yields have resulted in the degradation of soil and environmental qualities by increasing erosion and nutrient leaching in the groundwater and releasing greenhouses gases, such as carbon dioxide (CO2) and nitrous oxide (N2O), that cause global warming in the atmosphere by oxidation of soil organic matter. Consequently, management practices that sustain crop yields and improve soil and environmental qualities are needed. This paper reviews the findings of the effects of tillage practices, cover crops, and nitrogen (N) fertilization rates on crop yields, soil organic carbon (C) and N concentrations, and nitrate (NO3)-N leaching from the soil. Studies indicate that conservation tillage, such as no-till or reduced till, can increase soil organic C and N concentrations at 0- to 20-cm depth by as much as 7-17% in 8 years compared with conventional tillage without significantly altering crop yields. Similarly, cover cropping and 80-180 kg N ha(-1) year(-1) fertilization can increase soil organic C and N concentrations by as much as 4-12% compared with no cover cropping or N fertilization by increasing plant biomass and amount of C and N inputs to the soil. Reduced till, cover cropping, and decreased rate of N fertilization can reduce soil N leaching compared with conventional till, no cover cropping, and full rate of N fertilization. Management practices consisting of combinations of conservation tillage, mixture of legume and nonlegume cover crops, and reduced rate of N fertilization have the potentials for sustaining crop yields, increasing soil C and N storage, and reducing soil N leaching, thereby helping to improve soil and water qualities. Economical and social analyses of such practices are needed to find whether they are cost effective and acceptable to the farmers.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  8. Carbon dioxide exchange of a perennial bioenergy crop cultivation on a mineral soil

    NASA Astrophysics Data System (ADS)

    Lind, Saara E.; Shurpali, Narasinha J.; Peltola, Olli; Mammarella, Ivan; Hyvönen, Niina; Maljanen, Marja; Räty, Mari; Virkajärvi, Perttu; Martikainen, Pertti J.

    2016-03-01

    One of the strategies to reduce carbon dioxide (CO2) emissions from the energy sector is to increase the use of renewable energy sources such as bioenergy crops. Bioenergy is not necessarily carbon neutral because of greenhouse gas (GHG) emissions during biomass production, field management and transportation. The present study focuses on the cultivation of reed canary grass (RCG, Phalaris arundinacea L.), a perennial bioenergy crop, on a mineral soil. To quantify the CO2 exchange of this RCG cultivation system, and to understand the key factors controlling its CO2 exchange, the net ecosystem CO2 exchange (NEE) was measured from July 2009 until the end of 2011 using the eddy covariance (EC) method. The RCG cultivation thrived well producing yields of 6200 and 6700 kg DW ha-1 in 2010 and 2011, respectively. Gross photosynthesis (GPP) was controlled mainly by radiation from June to September. Vapour pressure deficit (VPD), air temperature or soil moisture did not limit photosynthesis during the growing season. Total ecosystem respiration (TER) increased with soil temperature, green area index and GPP. Annual NEE was -262 and -256 g C m-2 in 2010 and 2011, respectively. Throughout the study period from July 2009 until the end of 2011, cumulative NEE was -575 g C m-2. Carbon balance and its regulatory factors were compared to the published results of a comparison site on drained organic soil cultivated with RCG in the same climate. On this mineral soil site, the RCG had higher capacity to take up CO2 from the atmosphere than on the comparison site.

  9. Candidate perennial bioenergy grasses have a higher albedo than annual row crops

    NASA Astrophysics Data System (ADS)

    Miller, J. N.; VanLoocke, A.; Gomez-Casanovas, N.; Bernacchi, C.

    2015-12-01

    The production of perennial cellulosic feedstocks for bioenergy presents the potential to diversify regional economies and the national energy supply, while also serving as climate 'regulators' due to a number of biogeochemical and biogeophysical differences relative to row crops. Numerous observational and model based approaches have investigated biogeochemical tradeoffs, such as increased carbon sequestration and increased water use, associated with growing cellulosic feedstocks. A less understood aspect is the biogeophysical changes associated with the difference in albedo (α), which could alter the local energy balance and cause local to regional cooling several times larger than that associated with offsetting carbon. Here, we established paired fields of Miscanthus × giganteus (miscanthus) and Panicum virgatum (switchgrass), two of the leading perennial cellulosic feedstock candidates, and traditional annual row crops in the highly productive "Corn-belt". Our results show that miscanthus did and switchgrass did not have an overall higher α than current row crops but a strong seasonal pattern existed. Both perennials had consistently higher growing season α than row crops and winter α did not differ. The lack of observed differences in winter α, however, masked an interaction between snow cover and species differences, with the perennial species, compared with the row crops, having a higher α when snow was absent and a much lower α when snow was present. Overall, these changes resulted in an average net reduction in annual absorbed energy of about 5 W/m2 for switchgrass and about 8 W/m2 for miscanthus relative to annual crops. Therefore, the conversion from annual row to perennial crops alters the radiative balance of the surface via changes in α and could lead to regional cooling.

  10. Climate change and the flowering time of annual crops.

    PubMed

    Craufurd, P Q; Wheeler, T R

    2009-01-01

    Crop production is inherently sensitive to variability in climate. Temperature is a major determinant of the rate of plant development and, under climate change, warmer temperatures that shorten development stages of determinate crops will most probably reduce the yield of a given variety. Earlier crop flowering and maturity have been observed and documented in recent decades, and these are often associated with warmer (spring) temperatures. However, farm management practices have also changed and the attribution of observed changes in phenology to climate change per se is difficult. Increases in atmospheric [CO(2)] often advance the time of flowering by a few days, but measurements in FACE (free air CO(2) enrichment) field-based experiments suggest that elevated [CO(2)] has little or no effect on the rate of development other than small advances in development associated with a warmer canopy temperature. The rate of development (inverse of the duration from sowing to flowering) is largely determined by responses to temperature and photoperiod, and the effects of temperature and of photoperiod at optimum and suboptimum temperatures can be quantified and predicted. However, responses to temperature, and more particularly photoperiod, at supraoptimal temperature are not well understood. Analysis of a comprehensive data set of time to tassel initiation in maize (Zea mays) with a wide range of photoperiods above and below the optimum suggests that photoperiod modulates the negative effects of temperature above the optimum. A simulation analysis of the effects of prescribed increases in temperature (0-6 degrees C in +1 degree C steps) and temperature variability (0% and +50%) on days to tassel initiation showed that tassel initiation occurs later, and variability was increased, as the temperature exceeds the optimum in models both with and without photoperiod sensitivity. However, the inclusion of photoperiod sensitivity above the optimum temperature resulted in a

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

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

    Soil quality of shallow paddy soils may be improved by introducing upland crops and thus a more diverse crop cultivation pattern. Yet, the causal relationship between crop performance and enhanced soil traits in rice-upland crop rotations remains elusive. The objectives of this study were to (i) find correlations among soil properties under different rice-upland crop systems and link selected soil properties to rice growth and yield, (ii) present appropriate values of soil parameters for sustainable rice productivity in heavy clay soil, (iii) evaluate the effect of rotating rice with upland crops on rice yield and economic benefit in a long-term experiment. A rice-upland crop rotational field experiment in the Vietnamese Mekong delta was conducted for 10 years using a randomized complete block design with four treatments and four replications. Treatments were: (i) rice-rice-rice (control - conventional system as farmers' practice), (ii) rice-maize-rice, (iii) rice-mung bean-rice, and (iv) rice-mung bean-maize. Soil and plant sampling were performed after harvest of the rice crop at the end of the final winter-spring cropping season (i.e. year 10). Results show differences in rice growth and yield, and economic benefit as an effect of the crop rotation system. These differences were linked with changes in bulk density, soil porosity, soil aggregate stability index, soil penetration resistance, soil macro-porosity, soil organic carbon, acid hydrolysable soil C and soil nutrient elements, especially at soil depth of 20-30 cm. This is evidenced by the strong correlation (P < 0.01) between rice plant parameters, rice yield and soil properties such as bulk density, porosity, penetration resistance, soil organic carbon and Chydrolysable. It turned out that good rice root growth and rice yield corresponded to bulk density values lower than 1.3 Mg m-3, soil porosity higher than 50%, penetration resistance below 1.0 MPa, and soil organic carbon above 25 g kg-1. The optimal

  12. Interaction between soil mineralogy and the application of crop residues on aggregate stability and hydraulic conductivity of the soil

    NASA Astrophysics Data System (ADS)

    Lado, M.; Kiptoon, R.; Bar-Tal, A.; Wakindiki, I. I. C.; Ben-Hur, M.

    2012-04-01

    One of the main goals of modern agriculture is to achieve sustainability by maintaining crop productivity while avoiding soil degradation. Intensive cultivation could lead to a reduction in soil organic matter that could affect the structure stability and hydraulic conductivity of the soil. Moreover, crops extract nutrients from the soil that are taken away from the field when harvested, and as a consequence, the addition of fertilizers to the soil is necessary to maintain crop productivity. One way to deal with these problems is to incorporate crop residues into the soil after harvest. Crop residues are a source of organic matter that could improve soil physical properties, such as aggregate stability and soil hydraulic conductivity. However, this effect could vary according to other soil properties, such as clay content, clay mineralogy, and the presence of other cementing materials in the soil (mainly carbonates and aluminum and iron oxides). In the present work, the interaction between the addition of chickpea crop residues to the soil and clay mineralogy on aggregate stability and saturated hydraulic conductivity were studied. Chickpea plant residues were added at a rate of 0.5% (w/w) to smectitic, kaolinitic, illitic and non-phyllosilicate soils from different regions. The soils without (control) and with chickpea residues were incubated for 0, 3, 7 and 30 days, and the saturated hydraulic conductivity of the soils was measured in columns after each incubation time. The response of hydraulic conductivity to the addition of residues and incubation time was different in the soils with various mineralogies, although in general, the addition of chickpea residues increased the saturated hydraulic conductivity as compared with the control soils. This positive effect of crop residues on hydraulic conductivity was mainly a result of improved aggregate stability and resistance to slaking during wetting.

  13. Perennial grassland establishment and production response following different annual cropping systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Developing efficient, economical methods of perennial mixture establishment in a semi-arid environment is needed for grazing and conservation purposes. We evaluated different perennial monocultures and mixtures planted into various annual crops (spring wheat, corn, soybean, dry pea, and canola) to ...

  14. Uptake of cesium-137 by crops from contaminated soils

    SciTech Connect

    Demirel, H.; Oezer, I.; Celenk, I.; Halitligil, M.B.; Oezmen, A.

    1994-11-01

    The Turkish tea crop was contaminated following the Chernobyl nuclear accident. Finding ways to dispose of the contaminated tea (Camellia sinensis L.) without damaging the environment was the goal of this research conducted at the Turkish Atomic Energy Authority (TAEA). In this study, an investigation was made of {sup 137}Cs activities of the plants and the ratios of transfer of {sup 137}Cs activity to plants when the contaminated tea was applied to the soil. Experiments were conducted in the field and in pots under greenhouse conditions. The activities of the tea applied in the field ranged from 12 500 to 72 800 Bq/m{sup 2}, whereas this activity was constant at 8000 Bq/pot in the greenhouse experiment. The transfer of {sup 137}Cs from soil to the plants was between 0.037 and 1.057% for wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), corn (Zea mays indentata Sturt), bean (Phaseolus vulgaris L.), lettuce (Lactuca sativa L.), and grass (Lolium perenne L.). The ratio of the transfer of {sup 137}Cs activity to plants increased as the activity {sup 137}Cs in tea applied to soil was increased. The activity in the plants increased due to increased uptake of {sup 137}Cs by plants. 12 refs., 2 figs., 2 tabs.

  15. Cover crops for enriching soil carbon and nitrogen under bioenergy sorghum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil carbon (C) and nitrogen (N) can be enriched with cover crops under agronomic crops, but little is known about their enrichment under bioenergy crops. Legume (hairy vetch [Vicia villosa Roth]), nonlegume (rye [Secaele cereale L.]), a mixture of legume and nonlegume (hairy vetch and rye) and a co...

  16. Regional estimation of soil C stocks and CO2 emissions as influenced by cropping systems and soil type

    NASA Astrophysics Data System (ADS)

    Farina, Roberta; Marchetti, Alessandro; Di Bene, Claudia

    2015-04-01

    Soil organic matter (SOM) is of crucial importance for agricultural soil quality and fertility. At global level soil contains about three times the carbon stored in the vegetation and about twice that present in the atmosphere. Soil could act as source and sink of carbon, influencing the balance of CO2 concentration and consequently the global climate. The sink/source ratio depends on many factors that encompass climate, soil characteristics and different land management practices. Thus, the relatively large gross exchange of GHGs between atmosphere and soils and the significant stocks of carbon in soils, may have significant impact on climate and on soil quality. To quantify the dynamics of C induced by land cover change and the spatial and temporal dynamics of C sources and sinks at regional and, potentially, at national and global scales, we propose a methodology, based on a bio-physical model combined with a spatial explicit database to estimate C stock changes and emissions/removals. The study has been conducted in a pilot region in Italy (Apulia, Foggia province), considering the typical cropping systems of the area, namely rainfed cereals, tomato, vineyard and olives. For this purpose, the model RothC10N (Farina et al., 2013), that simulates soil C dynamics, has been modified to work directly in batch using data of climate, soil (over 290 georeferenced soil profiles), annual agriculture land use (1200 observations) The C inputs from crops have been estimated using statistics and data from literature. The model was run to equilibrium for each point of soil, in order to make all the data homogeneous in terms of time. The obtained data were interpolate with geostatisical procedures, obtaining a set of 30x30 km grid with the initial soil C. The new layer produced, together with soil and land use layers, were used for a long-term run (12 years). Results showed that olive groves and vineyards were able to stock a considerable amount of C (from 0.4 to 1.5 t ha-1 y

  17. Reproductive Allocation of Biomass and Nitrogen in Annual and Perennial Lesquerella Crops

    PubMed Central

    PLOSCHUK, E. L.; SLAFER, G. A.; RAVETTA, D. A.

    2005-01-01

    • Background and Aims The use of perennial crops could contribute to increase agricultural sustainability. However, almost all of the major grain crops are herbaceous annuals and opportunities to replace them with more long-lived perennials have been poorly explored. This follows the presumption that the perennial life cycle is associated with a lower potential yield, due to a reduced allocation of biomass to grains. The hypothesis was tested that allocation to perpetuation organs in the perennial L. mendocina would not be directly related to a lower allocation to seeds. • Methods Two field experiments were carried on with the annual Lesquerella fendleri and the iteroparous perennial L. mendocina, two promising oil-seed crops for low-productivity environments, subjected to different water and nitrogen availability. • Key Results Seed biomass allocation was similar for both species, and unresponsive to water and nitrogen availability. Greater root and vegetative shoot allocation in the perennial was counterbalanced by a lower allocation to other reproductive structures compared with the annual Lesquerella. Allometric relationships revealed that allocation differences between the annual and the perennial increased linearly with plant size. The general allocation patterns for nitrogen did not differ from those of biomass. However, nitrogen concentrations were higher in the vegetative shoot and root of L. mendocina than of L. fendleri but remained stable in seeds of both species. • Conclusions It is concluded that vegetative organs are more hierarchically important sinks in L. mendocina than in the annual L. fendleri, but without disadvantages in seed hierarchy. PMID:15863469

  18. Soil quality parameters for row-crop and grazed pasture systems with agroforestry buffers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Incorporation of trees and establishment of buffers are practices that can improve soil quality. Soil enzyme activities and water stable aggregates are sensitive indices for assessing soil quality by detecting early changes in soil management. However, studies comparing grazed pasture and row crop...

  19. EPIC Simulations of Crop Yields and Soil Organic Carbon in Iowa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Depending on management, soil organic carbon is source or sink of atmospheric carbon dioxide. The Environmental Policy Integrated Climate (EPIC) model is a useful tool for predicting impacts of soil management on crop yields and soil organic carbon. We used EPIC-Century to simulate changes in soil o...

  20. Influence of cover crops and crop residue treatment on soil organic carbon stocks evaluated in Swedish long-term field experiments

    NASA Astrophysics Data System (ADS)

    Poeplau, Christopher; Bolinder, Martin A.; Börjesson, Gunnar; Kätterer, Thomas

    2015-04-01

    Soil organic carbon (SOC) stocks in agricultural soils are strongly controlled by management. In this study we quantified the effect of cover crops and crop residue management on SOC stocks in Swedish long-term experiments. Eight pairs of cover crop (undersown ryegrass) vs. no cover crop were investigated in Swedish long-term field experiments (16 to 24 years). Yields of the main crop were not affected by the cover crop. Cover crops significantly increased SOC stocks, with a mean carbon sequestration rate in all experiments (excluding one) of 0.32±0.29 Mg C ha-1 yr-1. Interestingly, this sequestration is similar to that estimated for a U.S.experiment, where ryegrass growth is much less temperature- and light-limited than under Swedish conditions. This sequestration rate is also the same as that recently reported for many other cover crops in a global meta-analysis but less than SOC changes in ley-dominated rotations which under Nordic conditions were shown to accumulate in average 0.5 Mg C ha-1 yr-1 more carbon compared to exclusively annual cropping systems. Thus, originally introduced in agricultural rotations to reduce nitrate leaching, cover crops are also an effective practice to increase SOC stocks, even at relatively high latitudes. The effect of crop residue treatment was studied in 16 pairs of straw incorporated (SI) vs. straw removed (SR) treatments in six Swedish long-term field experiments. Data series on SOC with 5-28 sampling dates during 27-53 years were analysed using ICBM, a dynamic SOC model. At five out of six sites, the humification coefficient for straw (hlitter; the fraction of straw C that is entering the slow C pool) was much smaller (0-0.09) than the ICBM default h-value for plant material estimated in previous studies (0.125). The derived hlitter-values and thus the stabilization of straw-derived carbon increased significantly with clay content. For an Italian site (with five pairs of SI vs. SR) that was used for model validation we found

  1. Ruminant Grazing of Cover Crops: Effects on Soil Properties and Agricultural Production

    ERIC Educational Resources Information Center

    Poffenbarger, Hanna

    2010-01-01

    Integrating livestock into a cropping system by allowing ruminant animals to graze cover crops may yield economic and environmental benefits. The effects of grazing on soil physical properties, soil organic matter, nitrogen cycling and agricultural production are presented in this literature review. The review found that grazing cover crops…

  2. Impacts of organic conservation tillage systems on crops, weeds, and soil quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organic farming has been identified as promoting soil quality even though tillage is used for weed suppression. Adopting conservation tillage practices can enhance soil quality in cropping systems where synthetic agrichemicals are used for crop nutrition and weed control. Attempts have been made t...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  4. Best management practices: Managing cropping systems for soil protection and bioenergy production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  5. Developing a Foundation for Constructing New Curricula in Soil, Crop, and Turfgrass Sciences

    ERIC Educational Resources Information Center

    Jarvis, Holly D.; Collett, Ryan; Wingenbach, Gary; Heilman, James L.; Fowler, Debra

    2012-01-01

    Some soil and crop science university programs undergo curricula revision to maintain relevancy with their profession and/or to attract the best students to such programs. The Department of Soil and Crop Sciences at Texas A&M University completed a thorough data gathering process as part of its revision of the undergraduate curriculum and…

  6. Soil water improvements with the long-term use of a winter rye cover crop

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Midwestern United States is projected to experience increasing rainfall variability. One approach to mitigate climate impacts is to utilize crop and soil management practices that enhance soil water storage, reducing the risks of flooding as well as drought-induced crop water stress. While some ...

  7. Can novel management practice improve soil and environmental quality and sustain crop yield simultaneously?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Little is known about management practices that can simultaneously improve soil and environmental quality and sustain crop yields. The effect of a combination of tillage, crop rotation, and N fertilization on soil C and N, global warming potential (GWP), greenhouse gas intensity (GHGI), and malt bar...

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

    PubMed

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

    2015-05-01

    Two consecutive years (4-crop) experiments were conducted to study the influence of different paddy rice-upland crop rotation in cold-waterlogged paddy field on the growth of crops and soil characteristics. The result showed that compared with the rice-winter fallow (CK) pattern, the two-year average yield of paddy rice under four rotation modes, including rape-rice (R-R), spring corn-rice (C-R), Chinese milk vetch-rice (M-R) and bean-rice (B-R), were increased by 5.3%-26.7%, with significant difference observed in C-R and R-R patterns. Except for M-R pattern, the annual average total economic benefits were improved by 79.0%-392.4% in all rotation pattern compared with the CK, and the ration of output/input was enhanced by 0.06-0.72 unit, with the most significant effect found in the C-R pattern. Likewise, compared with the CK, the contents of chlorophyll and carotenoid, and net photosynthetic rate (Pn) of rice plant were all increased during the full-tillering stage of rice in all rotation patterns. The rusty lines and rusty spots of soils were more obvious compared with the CK during the rice harvest, particularly in R-R, C-R and B-R patterns. The ratio of water-stable soil macro aggregates of plough layer of soil (> 2 mm) decreased at different levels in all rotation patterns while the ratios of middle aggregate (0.25-2 mm, expect for M-R) and micro aggregate of soil (< 0.25 mm) were opposite. There was a decreasing trend for soil active reducing agents in all rotation patterns, whereas the available nutrient increased. The amounts of soil bacteria in C-R and B-R patterns, fungi in B-R rotation pattern, cellulose bacteria in R-R, C-R and B-R patterns and N-fixing bacteria in B-R pattern were improved by 285.7%-403.0%, 221.7%, 64.6-92.2% and 162.2%, respectively. Moreover, the differences in all microorganisms were significant. Thus, based on the experimental results of cold-waterlogged paddy field, it was concluded that changing from single cropping rice system

  9. An integrated soil-crop system model for water and nitrogen management in North China

    PubMed Central

    Liang, Hao; Hu, Kelin; Batchelor, William D.; Qi, Zhiming; Li, Baoguo

    2016-01-01

    An integrated model WHCNS (soil Water Heat Carbon Nitrogen Simulator) was developed to assess water and nitrogen (N) management in North China. It included five main modules: soil water, soil temperature, soil carbon (C), soil N, and crop growth. The model integrated some features of several widely used crop and soil models, and some modifications were made in order to apply the WHCNS model under the complex conditions of intensive cropping systems in North China. The WHCNS model was evaluated using an open access dataset from the European International Conference on Modeling Soil Water and N Dynamics. WHCNS gave better estimations of soil water and N dynamics, dry matter accumulation and N uptake than 14 other models. The model was tested against data from four experimental sites in North China under various soil, crop, climate, and management practices. Simulated soil water content, soil nitrate concentrations, crop dry matter, leaf area index and grain yields all agreed well with measured values. This study indicates that the WHCNS model can be used to analyze and evaluate the effects of various field management practices on crop yield, fate of N, and water and N use efficiencies in North China. PMID:27181364

  10. An integrated soil-crop system model for water and nitrogen management in North China

    NASA Astrophysics Data System (ADS)

    Liang, Hao; Hu, Kelin; Batchelor, William D.; Qi, Zhiming; Li, Baoguo

    2016-05-01

    An integrated model WHCNS (soil Water Heat Carbon Nitrogen Simulator) was developed to assess water and nitrogen (N) management in North China. It included five main modules: soil water, soil temperature, soil carbon (C), soil N, and crop growth. The model integrated some features of several widely used crop and soil models, and some modifications were made in order to apply the WHCNS model under the complex conditions of intensive cropping systems in North China. The WHCNS model was evaluated using an open access dataset from the European International Conference on Modeling Soil Water and N Dynamics. WHCNS gave better estimations of soil water and N dynamics, dry matter accumulation and N uptake than 14 other models. The model was tested against data from four experimental sites in North China under various soil, crop, climate, and management practices. Simulated soil water content, soil nitrate concentrations, crop dry matter, leaf area index and grain yields all agreed well with measured values. This study indicates that the WHCNS model can be used to analyze and evaluate the effects of various field management practices on crop yield, fate of N, and water and N use efficiencies in North China.

  11. [Advances in effects of insecticidal crystal proteins released from transgenic Bt crops on soil ecology].

    PubMed

    Zhou, Xue-Yong; Liu, Ning; Zhao, Man; Li, He; Zhou, Lang; Tang, Zong-Wen; Cao, Fei; Li, Wei

    2011-05-01

    With the large scale cultivation of transgenic crops expressing Bacillus thuringiensis (Bt) insecticidal crystal proteins in the world, the problem of environmental safety caused by these Bt crops has received extensive attention. These insecticidal crystal proteins can be released into the soil continuously in the growing period of Bt plants. If their accumulation of the insecticidal crystal proteins exceeds consumption by insect larvae and degradation by the environmental factors, these insecticidal crystal proteins could constitute a hazard to non-target insects and soil microbiota. There are three main ways to release insecticidal crystal proteins into soil for Bt plants: root exudates, pollen falling, and crop reside returning. The Bt insecticidal crystal proteins released into soil can be adsorbed rapidly by active soil particles and the absorption equilibrium attained within 1-3 h. The adsorption protects Bt insecticidal crystal proteins against soil microbial degradation or enzyme degradation, which leads to remarkable prolong of the persistence of insecticidal activity. The change of soil microorganism species is an important index for evaluating the effect of Bt plants on soil ecology. The research showed that these insecticidal crystal proteins released by the Bt plant root exudates or Bt organism had no toxicity to the soil earthworms, nematodes, protozoa, bacteria and fungi; however, it could reduce the mycelium length of the arbuscular mycorrhizal fungi (AMF) and restrain AMF to form invasion unit. The influencing degree of Bt protein on soil enzyme activity varied with the releasing modes or growth period of Bt crops. Bt Cry1Ab protein can be taken up from soil by parts of following crops; however, different results were obtained with different commercial kits. To better understand the soil ecological evaluation about the insecticidal crystal proteins released from transgenic Bt crops, this review provides a comprehensive overview about the release

  12. Antibiotic uptake by vegetable crops from manure-applied soils.

    PubMed

    Kang, Dong Hee; Gupta, Satish; Rosen, Carl; Fritz, Vincent; Singh, Ashok; Chander, Yogesh; Murray, Helene; Rohwer, Charlie

    2013-10-23

    This study quantified the uptake of five antibiotics (chlortetracycline, monensin, sulfamethazine, tylosin, and virginiamycin) by 11 vegetable crops in two different soils that were fertilized with raw versus composted turkey and hog manures or inorganic fertilizer. Almost all vegetables showed some uptake of antibiotics from manure treatments. However, statistical testing showed that except for a few isolated treatments the concentrations of all antibiotics in vegetable tissues were generally less than the limits of quantification. Further testing of the significant treatments showed that antibiotic concentrations in vegetables from many of these treatments were not significantly different than the corresponding concentrations from the fertilizer treatment (matrix effect). All five antibiotic concentrations in the studied vegetables were <10 μg kg(-1). On the basis of the standards for maximum residue levels in animal tissues and suggested maximum daily intake based on body weight, this concentration would not pose any health risk unless one is allergic to that particular antibiotic.

  13. Imputing historical statistics, soils information, and other land-use data to crop area

    NASA Technical Reports Server (NTRS)

    Perry, C. R., Jr.; Willis, R. W.; Lautenschlager, L.

    1982-01-01

    In foreign crop condition monitoring, satellite acquired imagery is routinely used. To facilitate interpretation of this imagery, it is advantageous to have estimates of the crop types and their extent for small area units, i.e., grid cells on a map represent, at 60 deg latitude, an area nominally 25 by 25 nautical miles in size. The feasibility of imputing historical crop statistics, soils information, and other ancillary data to crop area for a province in Argentina is studied.

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

    PubMed

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

    2014-04-01

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

  15. Zonal Soil Type Determines Soil Microbial Responses to Maize Cropping and Fertilization

    PubMed Central

    Zhao, Mengxin; Wu, Linwei; Gao, Qun; Wang, Feng; Wen, Chongqing; Wang, Mengmeng; Liang, Yuting; Zhou, Jizhong

    2016-01-01

    ABSTRACT Soil types heavily influence ecological dynamics. It remains controversial to what extent soil types shape microbial responses to land management changes, largely due to lack of in-depth comparison across various soil types. Here, we collected samples from three major zonal soil types spanning from cold temperate to subtropical climate zones. We examined bacterial and fungal community structures, as well as microbial functional genes. Different soil types had distinct microbial biomass levels and community compositions. Five years of maize cropping (growing corn or maize) changed the bacterial community composition of the Ultisol soil type and the fungal composition of the Mollisol soil type but had little effect on the microbial composition of the Inceptisol soil type. Meanwhile, 5 years of fertilization resulted in soil acidification. Microbial compositions of the Mollisol and Ultisol, but not the Inceptisol, were changed and correlated (P < 0.05) with soil pH. These results demonstrated the critical role of soil type in determining microbial responses to land management changes. We also found that soil nitrification potentials correlated with the total abundance of nitrifiers and that soil heterotrophic respiration correlated with the total abundance of carbon degradation genes, suggesting that changes in microbial community structure had altered ecosystem processes. IMPORTANCE Microbial communities are essential drivers of soil functional processes such as nitrification and heterotrophic respiration. Although there is initial evidence revealing the importance of soil type in shaping microbial communities, there has been no in-depth, comprehensive survey to robustly establish it as a major determinant of microbial community composition, functional gene structure, or ecosystem functioning. We examined bacterial and fungal community structures using Illumina sequencing, microbial functional genes using GeoChip, microbial biomass using phospholipid fatty

  16. Zonal Soil Type Determines Soil Microbial Responses to Maize Cropping and Fertilization.

    PubMed

    Zhao, Mengxin; Sun, Bo; Wu, Linwei; Gao, Qun; Wang, Feng; Wen, Chongqing; Wang, Mengmeng; Liang, Yuting; Hale, Lauren; Zhou, Jizhong; Yang, Yunfeng

    2016-01-01

    Soil types heavily influence ecological dynamics. It remains controversial to what extent soil types shape microbial responses to land management changes, largely due to lack of in-depth comparison across various soil types. Here, we collected samples from three major zonal soil types spanning from cold temperate to subtropical climate zones. We examined bacterial and fungal community structures, as well as microbial functional genes. Different soil types had distinct microbial biomass levels and community compositions. Five years of maize cropping (growing corn or maize) changed the bacterial community composition of the Ultisol soil type and the fungal composition of the Mollisol soil type but had little effect on the microbial composition of the Inceptisol soil type. Meanwhile, 5 years of fertilization resulted in soil acidification. Microbial compositions of the Mollisol and Ultisol, but not the Inceptisol, were changed and correlated (P < 0.05) with soil pH. These results demonstrated the critical role of soil type in determining microbial responses to land management changes. We also found that soil nitrification potentials correlated with the total abundance of nitrifiers and that soil heterotrophic respiration correlated with the total abundance of carbon degradation genes, suggesting that changes in microbial community structure had altered ecosystem processes. IMPORTANCE Microbial communities are essential drivers of soil functional processes such as nitrification and heterotrophic respiration. Although there is initial evidence revealing the importance of soil type in shaping microbial communities, there has been no in-depth, comprehensive survey to robustly establish it as a major determinant of microbial community composition, functional gene structure, or ecosystem functioning. We examined bacterial and fungal community structures using Illumina sequencing, microbial functional genes using GeoChip, microbial biomass using phospholipid fatty acid

  17. Greenhouse gas fluxes and budget for an annual cropping system in the Red River Valley, Manitoba, Canada

    NASA Astrophysics Data System (ADS)

    Glenn, Aaron James

    Agriculture contributes significantly to national and global greenhouse gas (GHG) inventories but there is considerable control over management decisions and changes in production methods could lead to a significant reduction and possible mitigation of emissions from the sector. For example, conservation tillage practices have been suggested as a method of sequestering atmospheric carbon dioxide (CO2), however, many questions remain unanswered regarding the short-term efficacy of the production method and knowledge gaps exist regarding possible interactions with essential nutrient cycles, and the production of non-CO2 GHGs, such as nitrous oxide (N2O). Between autumn 2005 and 2009, a micrometeorological flux system was used to determine net CO2 and (N2O exchange from an annual cropping system situated on clay soil in the Red River Valley of southern Manitoba. Four plots (4-ha each) were independently evaluated and planted to corn in 2006 and faba bean in 2007; in 2008, two spring wheat plots were monitored. As well, during the non-growing season in 2006-2007 following corn harvest, a second micrometeorological flux system capable of simultaneously measuring stable C isotopologue (12CO2 and 13CO 2) fluxes was operated at the site. Tillage intensity and crop management practices were examined for their influence on GHG emissions. Significant inter-annual variability in CO2 and (N2O fluxes as a function of crop and related management activities was observed. Tillage intensity did not affect GHG emissions from the site. After accounting for harvest removals, the net ecosystem C budgets were 510 (source), 3140 (source) and -480 (sink) kg C/ha/year for the three respective crop years, summing to a three-year loss of 3170 kg C/ha. Stable C isotope flux measurements during the non-growing season following corn harvest indicated that approximately 70 % and 20 -- 30 % of the total respiration flux originated from crop residue C during the fall of 2006 and spring of 2007

  18. Developing High-resolution Soil Database for Regional Crop Modeling in East Africa

    NASA Astrophysics Data System (ADS)

    Han, E.; Ines, A. V. M.

    2014-12-01

    The most readily available soil data for regional crop modeling in Africa is the World Inventory of Soil Emission potentials (WISE) dataset, which has 1125 soil profiles for the world, but does not extensively cover countries Ethiopia, Kenya, Uganda and Tanzania in East Africa. Another dataset available is the HC27 (Harvest Choice by IFPRI) in a gridded format (10km) but composed of generic soil profiles based on only three criteria (texture, rooting depth, and organic carbon content). In this paper, we present a development and application of a high-resolution (1km), gridded soil database for regional crop modeling in East Africa. Basic soil information is extracted from Africa Soil Information Service (AfSIS), which provides essential soil properties (bulk density, soil organic carbon, soil PH and percentages of sand, silt and clay) for 6 different standardized soil layers (5, 15, 30, 60, 100 and 200 cm) in 1km resolution. Soil hydraulic properties (e.g., field capacity and wilting point) are derived from the AfSIS soil dataset using well-proven pedo-transfer functions and are customized for DSSAT-CSM soil data requirements. The crop model is used to evaluate crop yield forecasts using the new high resolution soil database and compared with WISE and HC27. In this paper we will present also the results of DSSAT loosely coupled with a hydrologic model (VIC) to assimilate root-zone soil moisture. Creating a grid-based soil database, which provides a consistent soil input for two different models (DSSAT and VIC) is a critical part of this work. The created soil database is expected to contribute to future applications of DSSAT crop simulation in East Africa where food security is highly vulnerable.

  19. Soil Organic Carbon Response to Cover Crop and Nitrogen Fertilization under Bioenergy Sorghum

    NASA Astrophysics Data System (ADS)

    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, cereal rye, hairy vetch, and hairy vetch/cereal rye mixture) and two N fertilization rates (0 and 90 kg N ha-1) on soil organic C (SOC) at 0-5, 5-15, and 15-30 cm depths under forage and sweet sorghums from 2010 to 2013 in Fort Valley, GA. Cover crop biomass yield and C content were greater with vetch/rye mixture than vetch or rye alone and the control, regardless of sorghum species. Soil organic C was greater with vetch/rye than rye at 0-5 and 15-30 cm in 2011 and 2013 and greater with vetch than rye at 5-15 cm in 2011 under forage sorghum. Under sweet sorghum, SOC was greater with cover crops than the control at 0-5 cm, but greater with vetch and the control than vetch/rye at 15-30 cm. The SOC increased at the rates of 0.30 Mg C ha-1 yr-1 at 0-5 cm for rye and the control to 1.44 Mg C ha-1 yr-1 at 15-30 cm for vetch/rye and the control from 2010 to 2013 under forage sorghum. Under sweet sorghum, SOC also increased linearly at all depths from 2010 to 2013, regardless of cover crops. Nitrogen fertilization had little effect on SOC. Cover crops increased soil C storage compared with no cover crop due to greater crop residue C returned to the soil under forage and sweet sorghum and hairy vetch/cereal rye mixture had greater C storage than other cover crops under forage sorghum.

  20. Soil quality index as affected by different cropping systems in northwestern Himalayas.

    PubMed

    Sofi, J A; Bhat, A G; Kirmai, N A; Wani, J A; Lone, Aabid H; Ganie, Mumtaz A; Dar, G I H

    2016-03-01

    Soil quality assessment provides a tool for evaluating the sustainability of soils under different crop cafeterias. Our objective was to develop the soil quality index for evaluating the soil quality indicators under different cropping systems in northwest Himalaya-India. Composite soil samples were taken from the study area from different cropping systems which include T1 (forest soil control), T2 (rice-oilseed, lower belts), T3 (rice-oilseed, higher belts), T4 (rice-oats), T5 (rice-fallow), T6 (maize-oats), T7 (maize-peas), T8 (apple), T9 (apple-beans), and T10 (apple-maize). Physical, chemical, and biological soil indicators were determined, and it was found that soil enzyme activities involved in nutrient cycling were significantly higher in forest soils, which were reflected in higher levels of available pool of nutrients. Carbon stocks were found significantly higher in forest soil which was translated in improved soil physical condition. Principal component analysis (PCA) was performed to reduce multidimensionality of data followed by scoring by homothetic transformation of the selected indicators. Pearson's interclass correlation was performed to avoid redundancy, and highly correlated variables were not retained. Inclusion of legumes in the apple orchard floor recorded highest soil quality rating across the treatments. Cereal-based cropping systems were found in lower soil quality rating; however, the incorporation of peas in the system improved soil health.

  1. Assessment of Crop Water Requirement Methods for Annual Agricultural Water Allocation Planning

    NASA Astrophysics Data System (ADS)

    Aghdasi, F.; Sharifi, M. A.; van der Tol, C.

    2010-05-01

    The potential use of remote sensing in water resource and in particular in irrigation management has been widely acknowledged. However, in reality, operational applications of remote sensing in irrigation management are few. In this study, the applicability of the main available remote sensing based techniques of irrigation management is evaluated in a pilot area in Iran. The evaluated techniques include so called Crop Water Requirement "CWR" methods for the planning of annual water allocation in irrigated agriculture. A total of 40 years of historical weather data were classified into wet, normal, and dry years using a Standardised Precipitation Index (SPI). For each of these three classes the average CWR was calculated. Next, by applying Markov Chain Process to the time series of precipitation, the expected CWR for the forthcoming planning year was estimated. Using proper interpolation techniques the expected CWR at each station was converted to CWR map of the area, which was then used for annual water allocation planning. To estimate the crop water requirement, methods developed for the DEMETER project (DEMonstration of Earth observation Technologies in Routine irrigation advisory services) and Surface Energy Balance System "SEBS" algorithm were used, and their results were compared with conventional methods, including FAO-56 and lysimeter data amongst others. Use was made of both ASTER and MODIS images to determine crop water requirement at local and regional scales. Four methods of estimating crop coefficients were used: DEMETER Kc-NDVI, DEMETER Kc-analytical, FAO-56 and SEBS algorithm. Results showed that DEMETER (analytical approach) and FAO methods with lowest RMSE are more suitable methods for determination of crop coefficient than SEBS, which gives actual rather than potential evapotranspiration. The use of ASTER and MODIS images did not result in significantly different crop coefficients in the pilot area for the DEMETER analytical approach (α=0

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

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

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

  3. Drainage and leaching dynamics in a cropped hummocky soil landscape with erosion-affected pedogenesis

    NASA Astrophysics Data System (ADS)

    Gerke, Horst H.; Rieckh, Helene; Sommer, Michael

    2016-04-01

    Hummocky soil landscapes are characterized by 3D spatial patterns of soil types that result from erosion-affected pedogenesis. Due to tillage and water erosion, truncated profiles have been formed at steep and mid slopes and colluvial soils at hollows. Pedogenetic variations in soil horizons at the different hillslope positions suggested feedback effects between erosion affected soil properties, the water balances, and the crop growth and leaching rates. Water balance simulations compared uniform with hillslope position-specific crop and root growths for soils at plateau, flat mid slope, steep slope, and hollow using the Hydrus-1D program. The boundary condition data were monitored at the CarboZALF-D experimental field site, which was cropped with perennial lucerne (Medicago sativa L.) in 2013 and 2014. Crop and root growth was assumed proportional to observed leaf area index (LAI). Fluxes of dissolved organic and inorganic carbon (DOC, DIC) were obtained from simulated water fluxes and measured DOC and DIC concentrations. For the colluvic soil, the predominately upward flow led to a net input in DIC and DOC. For the truncated soils at steep slopes, a reduced crop growth caused an relative increase in drainage, suggesting an accelerated leaching, which in the long term could accelerate the soil development and more soil variations along eroding hillslopes in arable soil landscapes.

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

    NASA Astrophysics Data System (ADS)

    McDaniel, Marshall D.; Grandy, A. Stuart

    2016-11-01

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

  5. Testing the validity of a Cd soil quality standard in representative Mediterranean agricultural soils under an accumulator crop.

    PubMed

    Recatalá, L; Sánchez, J; Arbelo, C; Sacristán, D

    2010-12-01

    The validity of a quality standard for cadmium (Cd) in representative agricultural Mediterranean soils under an accumulator crop (Lactuca sativa L.) is evaluated in this work considering both its effect on the crop growth (biomass production) and the metal accumulation in the edible part of the plant. Four soils with different properties relevant to regulate the behaviour of heavy metals were selected from the Valencian Region, a representative area of the European Mediterranean Region. For all soils, the effective concentration of added Cd causing 50% inhibition (EC(50)) on the biomass production was much higher than the minimum legal concentration used to declare soils as contaminated by cadmium, i.e. 100 times the baseline value for Cd, in Spain (Spanish Royal Decree 9/2005). As expected, Cd toxicity in the crop was higher in the soils having less carbonate content. On the other hand, for all soils, from the second dose on, which represents 10-times the baseline value for Cd, the metal content in crops exceeded the maximum level established for leaf crops by the European legislation (Regulation EC no. 466/2001). Soil salinity and coarse textures make the accumulation of Cd in the edible part of the plant easier. Therefore, the legal baseline soil cadmium content established by the Spanish legislation seems not valid neither from the point of view of the effect on the crop growth nor from the point of view of the metal accumulation in the edible part of the plant. In order to realistically declare contaminated soils by heavy metals, soil quality standards should be proposed taking into account the soil properties. Further research in other agricultural areas of the region would improve the basis for proposing adequate soil quality standards for heavy metals as highlighted by the European Thematic Strategy for Soil Protection.

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

    PubMed

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

    2015-06-01

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

  7. Crabgrass (Digitaria sanguinalis) allelochemicals that interfere with crop growth and the soil microbial community.

    PubMed

    Zhou, Bin; Kong, Chui-Hua; Li, Yong-Hua; Wang, Peng; Xu, Xiao-Hua

    2013-06-05

    Three chemicals, veratric acid, maltol, and (−)-loliolide, were isolated from crabgrass and their structures were identified by spectroscopic analysis. The chemicals were detected in crabgrass root exudates and rhizosphere soils, and their concentrations ranged from 0.16 to 8.10 μg/g. At an approximate concentration determined in crabgrass root exudates, all chemicals significantly inhibited the growth of wheat, maize, and soybean and reduced soil microbial biomass carbon. Phospholipid fatty acid profiling showed that veratric acid, maltol, and (−)-loliolide affected the signature lipid biomarkers of soil bacteria, actinobacteria, and fungi, resulting in changes in soil microbial community structures. There were significant relationships between crop growth and soil microbes under the chemicals' application. Chemical-specific changes in the soil microbial community generated negative feedback on crop growth. The results suggest that veratric acid, maltol, and (−)-loliolide released from crabgrass may act as allelochemicals interfering with crop growth and the soil microbial community.

  8. Biochar application to temperate soils - effects on soil fertility and crop yield

    NASA Astrophysics Data System (ADS)

    Kloss, S.; Zehetner, F.; Feichtmair, S.; Wimmer, B.; Zechmeister-Boltenstern, S.; Kitzler, B.; Watzinger, A.; Soja, G.

    2012-04-01

    Biochar (BC) application to soil as a potential soil amendment is currently intensively explored. Depending on feedstock and highest treatment temperature (HTT), BC application to soil may contribute to the soil nutrient status by directly adding nutrients to the soil as well as by increasing pH, cation exchange and water holding capacity. These parameters are known to play an important role in the soil nutrient status and nutrient availability. A positive effect on plant growth after BC application to tropical soils has been observed repeatedly; however, the effect of BC application to soils in temperate climate regions is much less explored. We investigated the effect of BC to temperate soils and crop yield using a randomized pot experiment in a greenhouse with three agricultural soils (Planosol, Cambisol, Chernozem) and four BC types (from straw, mixed woodchips and vineyard pruning, all pyrolyzed at 525°C). In order to analyze the effect of pyrolysis temperature, we additionally applied vineyard pruning BC pyrolyzed at 400°C. Selected treatments were planted with mustard (Sinapis alba L.), followed by barley (Hordeum vulgare). Soil sampling was carried out after barley harvest. Investigated soil parameters included pH, electrical conductivity (EC), C/N ratio, cation exchange capacity (CEC), CAL-extractable P and K, EDTA extractable Cu, Fe, Mn, Zn as well as nitrogen supplying potential (NSP). Biomass production of the two crops was determined as well as its elemental composition. Biochar application (3% wood-based BC) caused a considerable pH increase for the acidic Planosol. The effect of BC application on CEC was dependent on the original status of the soil, notably soil pH and texture. 3 % BC application (wood) decreased CEC by 3.5 % and 10 % for the Chernozem and Cambisol, respectively, but increased CEC by 35 % for the acidic, sandy Planosol, which may be due to the strong liming effect found for the Planosol. BC application significantly raised CAL

  9. Predicting greenhouse gas emissions and soil carbon from changing pasture to an energy crop.

    PubMed

    Duval, Benjamin D; Anderson-Teixeira, Kristina J; Davis, Sarah C; Keogh, Cindy; Long, Stephen P; Parton, William J; DeLucia, Evan H

    2013-01-01

    Bioenergy related land use change would likely alter biogeochemical cycles and global greenhouse gas budgets. Energy cane (Saccharum officinarum L.) is a sugarcane variety and an emerging biofuel feedstock for cellulosic bio-ethanol production. It has potential for high yields and can be grown on marginal land, which minimizes competition with grain and vegetable production. The DayCent biogeochemical model was parameterized to infer potential yields of energy cane and how changing land from grazed pasture to energy cane would affect greenhouse gas (CO2, CH4 and N2O) fluxes and soil C pools. The model was used to simulate energy cane production on two soil types in central Florida, nutrient poor Spodosols and organic Histosols. Energy cane was productive on both soil types (yielding 46-76 Mg dry mass · ha(-1)). Yields were maintained through three annual cropping cycles on Histosols but declined with each harvest on Spodosols. Overall, converting pasture to energy cane created a sink for GHGs on Spodosols and reduced the size of the GHG source on Histosols. This change was driven on both soil types by eliminating CH4 emissions from cattle and by the large increase in C uptake by greater biomass production in energy cane relative to pasture. However, the change from pasture to energy cane caused Histosols to lose 4493 g CO2 eq · m(-2) over 15 years of energy cane production. Cultivation of energy cane on former pasture on Spodosol soils in the southeast US has the potential for high biomass yield and the mitigation of GHG emissions.

  10. Predicting Greenhouse Gas Emissions and Soil Carbon from Changing Pasture to an Energy Crop

    PubMed Central

    Duval, Benjamin D.; Anderson-Teixeira, Kristina J.; Davis, Sarah C.; Keogh, Cindy; Long, Stephen P.; Parton, William J.; DeLucia, Evan H.

    2013-01-01

    Bioenergy related land use change would likely alter biogeochemical cycles and global greenhouse gas budgets. Energy cane (Saccharum officinarum L.) is a sugarcane variety and an emerging biofuel feedstock for cellulosic bio-ethanol production. It has potential for high yields and can be grown on marginal land, which minimizes competition with grain and vegetable production. The DayCent biogeochemical model was parameterized to infer potential yields of energy cane and how changing land from grazed pasture to energy cane would affect greenhouse gas (CO2, CH4 and N2O) fluxes and soil C pools. The model was used to simulate energy cane production on two soil types in central Florida, nutrient poor Spodosols and organic Histosols. Energy cane was productive on both soil types (yielding 46–76 Mg dry mass⋅ha−1). Yields were maintained through three annual cropping cycles on Histosols but declined with each harvest on Spodosols. Overall, converting pasture to energy cane created a sink for GHGs on Spodosols and reduced the size of the GHG source on Histosols. This change was driven on both soil types by eliminating CH4 emissions from cattle and by the large increase in C uptake by greater biomass production in energy cane relative to pasture. However, the change from pasture to energy cane caused Histosols to lose 4493 g CO2 eq⋅m−2 over 15 years of energy cane production. Cultivation of energy cane on former pasture on Spodosol soils in the southeast US has the potential for high biomass yield and the mitigation of GHG emissions. PMID:23991028

  11. Integrated soil-crop system management: reducing environmental risk while increasing crop productivity and improving nutrient use efficiency in China.

    PubMed

    Zhang, Fusuo; Cui, Zhenling; Fan, Mingsheng; Zhang, Weifeng; Chen, Xinping; Jiang, Rongfeng

    2011-01-01

    During the past 47 yr (1961-2007), Chinese cereal production has increased by 3.2-fold, successfully feeding 22% of the global human population with only 9% of the world's arable land, but at high environmental cost and resource consumption. Worse, crop production has been stagnant since 1996 while the population and demand for food continue to rise. New advances for sustainability of agriculture and ecosystem services will be needed during the coming 50 yr to reduce environmental risk while increasing crop productivity and improving nutrient use efficiency. Here, we advocate and develop integrated soil-crop system management (ISSM). In this approach, the key points are (i) to take all possible soil quality improvement measures into consideration, (ii) to integrate the utilization of various nutrient resources and match nutrient supply to crop requirements, and (iii) to integrate soil and nutrient management with high-yielding cultivation systems. Recent field experiments have shed light on how ISSM can lead to significant increases in crop yields while increasing nutrient use efficiency and reducing environmental risk.

  12. Soil quality indicators of a mature alley-cropping agroforestry system in temperate North America

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although agroforestry practices are believed to improve soil quality, reports on long-term effects of alley cropping on soils within agroforestry in the temperate zone are limited. The objective of this study was to examine effects of management, landscape, and soil depth of an established agrofores...

  13. Soil greenhouse gas emissions affected by sheep grazing under dryland cropping systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sheep grazing to control weeds during fallow may influence soil greenhouse gas (CO2, N2O, and CH4) emissions by consuming crop residue and returning feces and urine to the soil. An experiment was conducted to evaluate the effect of sheep grazing compared to herbicide application on soil temperature ...

  14. Plant adaptation to acid soils: the molecular basis for crop aluminum resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aluminum (Al) toxicity on acid soils is a significant limitation to crop production worldwide, as approximately 50% of the world’s potentially arable soils are acidic. Because acid soils are such an important constraint to agriculture, understanding the mechanisms and genes conferring resistance to ...

  15. Soil sustainability as measured by carbon sequestration using carbon isotopes from crop-livestock management systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil Organic Carbon (SOC) is an integral part of maintaining and measuring soil sustainability. This study was undertaken to document and better understand the relationships between two livestock-crop-forage systems and the sequestration of SOC with regards to soil sustainability and was conducted o...

  16. [Population development characteristics of rice crop cultivated on aerobic soil with mulching].

    PubMed

    Sheng, Haijun; Shen, Qirong; Feng, Ke

    2004-01-01

    Field experiments were carried out to study the population development characteristics of rice crop cultivated both on aerobic and waterlogged soil conditions. The results showed that the whole growth duration of rice growing on aerobic soil was one week longer than that on waterlogged soil. Shorter and narrower leaves and smaller LAI of rice population were found on aerobic soil than on waterlogged soil, which resulted in a decreased photosynthesis, smaller amount and lighter weight of rice grains on aerobic soil, compared with those on waterlogged soil. Among the aerobic treatments, more tillers, lower percentage of filled grains and shorter duration of grain forming were found on soils covered with plastic film than on soils covered with semi-decomposed straw or without mulching. The rice grain yield was decreased in the order of waterlogged soil > aerobic soil covered with plastic film > aerobic soil covered with semi-decomposed straw > aerobic soil without mulching.

  17. Distribution of antibiotics in wastewater-irrigated soils and their accumulation in vegetable crops in the Pearl River Delta, southern China.

    PubMed

    Pan, Min; Wong, Chris K C; Chu, L M

    2014-11-19

    Wastewater is increasingly being used to irrigate agricultural land in many countries around the world. However, limited research has examined the occurrence of antibiotics in soil irrigated with wastewater and their accumulation in plants. This study aimed to determine the distribution of various types of antibiotics in different environmental matrices in the Pearl River Delta (PRD) region and to evaluate their accumulation and translocation in edible crops. Samples were collected from six sites in the PRD where either domestic wastewater or fishpond water was used for irrigation. Results showed that fishpond water irrigated soils had higher concentrations of antibiotics than wastewater-irrigated soils. Different trends were observed in the accumulation of antibiotics in the different edible parts of various crops. Despite the low human annual exposure to antibiotics through the consumption of edible crops (1.10 to 7950 μg/y), the potential adverse effects of antibiotics along the food chain should not be neglected.

  18. Microbial Activity in Organic Soils as Affected by Soil Depth and Crop

    PubMed Central

    Tate, Robert L.

    1979-01-01

    The microbial activity of Pahokee muck, a lithic medisaprist, and the effect of various environmental factors, such as position in the profile and type of plant cover, were examined. Catabolic activity for [7-14C]salicylic acid, [1,4-14C]succinate, and [1,2-14C]acetate remained reasonably constant in surface (0 to 10 cm) soil samples from a fallow (bare) field from late in the wet season (May to September) through January. Late in January, the microbial activity toward all three compounds decreased approximately 50%. The microbial activity of the soil decreased with increasing depth of soil. Salicylate catabolism was the most sensitive to increasing moisture deep in the soil profile. At the end of the wet season, a 90% decrease in activity between the surface and the 60- to 70-cm depth occurred. Catabolism of acetate and succinate decreased approximately 75% in the same samples. Little effect of crop was observed. Variation in the microbial activity, as measured by the catabolism of labeled acetate, salicylate, or succinate, was not significant between a sugarcane (Saccharum officinarum L.) field and a fallow field. The activity with acetate was insignificantly different in a St. Augustine grass [Stenotaphrum secundatum (Walt) Kuntz] field, whereas the catabolism of the remaining substrates was elevated in the grass field. These results indicate that the total carbon evolved from the different levels of the soil profile by the microbial community oxidizing the soil organic matter decreased as the depth of the soil column increased. However, correction of the amount of carbon yielded at each level for the bulk density of that level reveals that the microbial contribution to the soil subsidence is approximately equivalent throughout the soil profile above the water table. PMID:16345393

  19. Gypsum effects on crop yield and chemistry of soil, crop tissue, and vadose zone water: A meta-analysis.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gypsum has various potential benefits as a soil amendment, but data are lacking on gypsum effects on crop yields and on environmental impacts across diverse field sites. Gypsum studies were conducted in six states using a common design with three rates each of mined and flue gas desulfurization (FGD...

  20. Spectral properties of agricultural crops and soils measured from space, aerial, field and laboratory sensors

    NASA Technical Reports Server (NTRS)

    Bauer, M. E.; Vanderbilt, V. C.; Robinson, B. F.; Daughtry, C. S. T.

    1980-01-01

    It is pointed out that in order to develop the full potential of multispectral measurements acquired from satellite or aircraft sensors to monitor, map, and inventory agricultural resources, increased knowledge and understanding of the spectral properties of crops and soils are needed. The present state of knowledge is reviewed, emphasizing current investigations of the multispectral reflectance characteristics of crops and soils as measured from laboratory, field, aerial, and satellite sensor systems. The relationships of important biological and physical characteristics to their spectral properties of crops and soils are discussed. Future research needs are also indicated.

  1. Noah-MP-CROP: an integrated atmosphere-crop-soil modeling system for regional agro-climatic assessments.

    NASA Astrophysics Data System (ADS)

    Liu, X.; Barlage, M. J.; Chen, F.; Niyogi, D. S.; Zhou, G.

    2014-12-01

    Cropland plays an important role in land-atmosphere interactions. Integrating advanced regional-scale crop-growth modeling capabilities into a land surface model (LSM) is not only crucial for assessing potential impacts of climate change and climate variability on crop yields, but also can help to improve the representation of crop-atmosphere interactions in the Weather Research and Forecasting (WRF) Model. Therefore, the objectives of developing Noah-MP-CROP are: 1) provide high-spatial and high-temporal resolution regional agro-climatic related products; 2) enhance the simulations of cropland surface-fluxes in the WRF model for numerical weather prediction and regional climate modeling. Noah-MP is a new-generation of LSM that uses multiple parameterizations for land hydrology and energy processes. In this study, we couple species-specific crop phenology and carbon allocation schemes with Noah-MP-based complex simulations of canopy photosynthesis and soil moisture. The Noah-MP-CROP can be executed at field-scales or grid-scales of different spatial resolution and it also can be applied at multiple temporal scales. The major agriculture-related outputs include: grain mass, leaf mass, leaf area index, crop yield, growth primary production, growing degree days, soil temperature, soil moisture, and evapotranspiration. The model also allows us to conduct different assessments by using either historical, real-time, short-term forecast or future projected weather input data. In this study, we focus on evaluating the Noah-MP-CROP for the regional agro-climatic assessments in the U.S. Corn Belt. Model simulations are conducted at both field-scale (Bondville, IL and Mead, NE) and grid-scale (4km-resolution). At both field sites, model outputs of crop yield (grain mass), leaf area index and surface fluxes show strong agreement with observations. Also incorporating crop-growth models in Noah-MP improves the simulated latent heat and sensible heat fluxes during the crop

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

    NASA Technical Reports Server (NTRS)

    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.

  3. Establishment of five cover crops and total soil nutrient extraction in a humid tropical soil in the Peruvian Amazon

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In order to evaluate the establishment of five cover crops and their potential to increase soil fertility through nutrient extraction, an experiment was installed in the Research Station of Choclino, San Martin, Peru. Five cover crops were planted: Arachis pintoi Krapov. & W.C. Greg, Calopogonium m...

  4. Effects of recurrent rolling/crimping operations on cover crop termination, soil moisture, and soil strength for conservation organic systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rolling/crimping technology has been utilized to mechanically terminate cover crops in conservation agriculture. In the southeastern United States, to eliminate competition for valuable soil moisture, three weeks are typically required after rolling to plant a cash crop into the desiccated cover cro...

  5. [Continuous remediation of heavy metal contaminated soil by co-cropping system enhanced with chelator].

    PubMed

    Wei, Ze-Bin; Guo, Xiao-Fang; Wu, Qi-Tang; Long, Xin-Xian

    2014-11-01

    In order to elucidate the continuous effectiveness of co-cropping system coupling with chelator enhancement in remediating heavy metal contaminated soils and its environmental risk towards underground water, soil lysimeter (0.9 m x 0.9 m x 0.9 m) experiments were conducted using a paddy soil affected by Pb and Zn mining in Lechang district of Guangdong Province, 7 successive crops were conducted for about 2.5 years. The treatments included mono-crop of Sedum alfredii Hance (Zn and Cd hyperaccumulator), mono-crop of corn (Zea mays, cv. Yunshi-5, a low-accumulating cultivar), co-crop of S. alfredii and corn, and co-crop + MC (Mixture of Chelators, comprised of citric acid, monosodium glutamate waste liquid, EDTA and KCI with molar ratio of 10: 1:2:3 at the concentration of 5 mmol x kg(-1) soil). The changes of heavy metal concentrations in plants, soil and underground water were monitored. Results showed that the co-cropping system was suitable only in spring-summer seasons and significantly increased Zn and Cd phytoextraction. In autumn-winter seasons, the growth of S. alfredii and its phytoextraction of Zn and Cd were reduced by co-cropping and MC application. In total, the mono-crops of S. alfredii recorded a highest phytoextraction of Zn and Cd. However, the greatest reduction of soil Zn, Cd and Pb was observed with the co-crop + MC treatment, the reduction rates were 28%, 50%, and 22%, respectively, relative to the initial soil metal content. The reduction of this treatment was mainly attributed to the downwards leaching of metals to the subsoil caused by MC application. The continuous monitoring of leachates during 2. 5 year's experiment also revealed that the addition of MC increased heavy metal concentrations in the leaching water, but they did not significantly exceed the III grade limits of the underground water standard of China.

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

    NASA Astrophysics Data System (ADS)

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

    2016-08-01

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

  7. Gap filling strategies and error in estimating annual soil respiration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil respiration (Rsoil) is one of the largest CO2 fluxes in the global carbon (C) cycle. Estimation of annual Rsoil requires extrapolation of survey measurements or gap-filling of automated records to produce a complete time series. While many gap-filling methodologies have been employed, there is ...

  8. Microbial metabolic profiles in Australian soils with varying crop management strategies

    NASA Astrophysics Data System (ADS)

    Aldorri, Sind; McMillan, Mary; Pereg, Lily

    2015-04-01

    Cotton production belt in Australia is covering vast areas from subtropical to temperate and grassland. Soil types are mostly different variations of clay with mainly black, grey and red clay soil containing variable proportions of sand in it. Growers often grow cotton in rotation with other crops, such as wheat, beans and corn, and soil fertilization vary with a number of growers using organic amendments as a main or supplementary source of nutrients. We have collected soil samples from farms in different regions and with different crop management strategies and studied the metabolic signature of microbial communities using the Biolog Ecoplate system. The metabolic patterns, supplemented with molecular analysis of the community will further the understanding of the influence of crop and soil management on soil functions carried out by microbes.

  9. Perfluoroalkyl acid distribution in various plant compartments of edible crops grown in biosolids-amended soils.

    PubMed

    Blaine, Andrea C; Rich, Courtney D; Sedlacko, Erin M; Hundal, Lakhwinder S; Kumar, Kuldip; Lau, Christopher; Mills, Marc A; Harris, Kimberly M; Higgins, Christopher P

    2014-07-15

    Crop uptake of perfluoroalkyl acids (PFAAs) from biosolids-amended soil has been identified as a potential pathway for PFAA entry into the terrestrial food chain. This study compared the uptake of PFAAs in greenhouse-grown radish (Raphanus sativus), celery (Apium graveolens var. dulce), tomato (Lycopersicon lycopersicum), and sugar snap pea (Pisum sativum var. macrocarpon) from an industrially impacted biosolids-amended soil, a municipal biosolids-amended soil, and a control soil. Individual concentrations of PFAAs, on a dry weight basis, in mature, edible portions of crops grown in soil amended with PFAA industrially impacted biosolids were highest for perfluorooctanoate (PFOA; 67 ng/g) in radish root, perfluorobutanoate (PFBA; 232 ng/g) in celery shoot, and PFBA (150 ng/g) in pea fruit. Comparatively, PFAA concentrations in edible compartments of crops grown in the municipal biosolids-amended soil and in the control soil were less than 25 ng/g. Bioaccumulation factors (BAFs) were calculated for the root, shoot, and fruit compartments (as applicable) of all crops grown in the industrially impacted soil. BAFs were highest for PFBA in the shoots of all crops, as well as in the fruit compartment of pea. Root-soil concentration factors (RCFs) for tomato and pea were independent of PFAA chain length, while radish and celery RCFs showed a slight decrease with increasing chain length. Shoot-soil concentration factors (SCFs) for all crops showed a decrease with increasing chain length (0.11 to 0.36 log decrease per CF2 group). The biggest decrease (0.54-0.58 log decrease per CF2 group) was seen in fruit-soil concentration factors (FCFs). Crop anatomy and PFAA properties were utilized to explain data trends. In general, fruit crops were found to accumulate fewer long-chain PFAAs than shoot or root crops presumably due to an increasing number of biological barriers as the contaminant is transported throughout the plant (roots to shoots to fruits). These data were

  10. Impact of cover crops and tillage on porosity of podzolic soil

    NASA Astrophysics Data System (ADS)

    Błażewicz-Woźniak, M.; Konopiñski, M.

    2013-09-01

    The aim of the study was to determine the influence of cover crops biomass, mixed with the soil on different dates and with the use of different tools in field conditions. The cover crop biomass had a beneficial influence on the total porosity of the 0-20 cm layer of the soil after winter. The highest porosity was achievedwith cover crops of buckwheat, phacelia and mustard, the lowest with rye. During the vegetation period the highest porosity of soil was observed in the ridges. Among the remaining non-ploughing cultivations, pre-winter use of stubble cultivator proved to have a beneficial influence on the soil porosity, providing results comparable to those achieved in conventional tillage. The differential porosity of the soil was modified not only by the catch crops and the cultivation methods applied, but also by the sample collection dates, and it did change during the vegetation period. The highest content of macropores after winter was observed for the phacelia cover crop, and the lowest in the case of cultivation without any cover crops. Pre-winter tillage with the use of a stubble cultivator increased the amount of macropores in soil in spring, and caused the biggest participation of mesopores as compared with other non-ploughing cultivation treatments of the soil. The smallest amount of mesopores was found in the ridges.

  11. Impact of climate change on water balance components in Mediterranean rainfed olive orchards under tillage or cover crop soil management

    NASA Astrophysics Data System (ADS)

    Rodríguez-Carretero, María Teresa; Lorite, Ignacio J.; Ruiz-Ramos, Margarita; Dosio, Alessandro; Gómez, José A.

    2013-04-01

    crop on the transpiration of the olive orchard, indicating that a correct water and soil management is crucial for these systems especially under climate change conditions. Thus, a significant reduction of transpiration was detected when the cover crops were implanted. When the climatic conditions were more limited (reductions of around 21% for the annual precipitation and increases around 13% for reference evapotranspiration), the impact on olive orchards were critical, affecting seriously the profitability of the olive orchards. In this context, cover crops can be considered as part of adaptation strategies. Further studies will be required for the determination of optimal species and varieties to be used as cover crops to reduce the impact of climate change on olive orchards under semi-arid conditions. References Abazi U, Lorite IJ, Cárceles B, Martínez-Raya A, Durán VH, Francia JR, Gómez JA (2013) WABOL: A conceptual water balance model for analyzing rainfall water use in olive orchards under different soil and cover crop Management strategies. Computers and Electronics in Agriculture 91:35-48 Dosio A, Paruolo P (2011) Bias correction of the ENSEMBLES high-resolution climate change projections for use by impact models: Evaluation on the present climate. Journal of Geophysical Research, V 116, D16106, doi:10.1029/2011JD015934 Dosio A, Paruolo P, Rojas R (2012) Bias correction of the ENSEMBLES high resolution climate change projections for use by impact models: Analysis of the climate change signal. Journal of Geophysical Research, V 117, D17, doi: 10.1029/2012JD017968

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

    PubMed

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

    2011-10-01

    In recent years, simulation models have been used as a complementary tool for research and for quantifying soil carbon sequestration under widely varying conditions. This has improved the understanding and prediction of soil organic carbon (SOC) dynamics and crop yield responses to soil and climate conditions and crop management scenarios. The goal of the present study was to estimate the changes in SOC for different cropping systems in West Africa using a simulation model. A crop rotation experiment conducted in Farakô-Ba, Burkina Faso was used to evaluate the performance of the cropping system model (CSM) of the Decision Support System for Agrotechnology Transfer (DSSAT) for simulating yield of different crops. Eight crop rotations that included cotton, sorghum, peanut, maize and fallow, and three different management scenarios, one without N (control), one with chemical fertilizer (N) and one with manure applications, were studied. The CSM was able to simulate the yield trends of various crops, with inconsistencies for a few years. The simulated SOC increased slightly across the years for the sorghum-fallow rotation with manure application. However, SOC decreased for all other rotations except for the continuous fallow (native grassland), in which the SOC remained stable. The model simulated SOC for the continuous fallow system with a high degree of accuracy normalized root mean square error (RMSE)=0·001, while for the other crop rotations the simulated SOC values were generally within the standard deviation (s.d.) range of the observed data. The crop rotations that included a supplemental N-fertilizer or manure application showed an increase in the average simulated aboveground biomass for all crops. The incorporation of this biomass into the soil after harvest reduced the loss of SOC. In the present study, the observed SOC data were used for characterization of production systems with different SOC dynamics. Following careful evaluation of the CSM with

  13. Towards a Process-based Representation of Annual Crops Within the Land Surface Model JULES

    NASA Astrophysics Data System (ADS)

    van den Hoof, C.; Vidale, P.

    2008-05-01

    The purpose of this work is to introduce a generic crop structure within the Joint UK Land surface Exchange Scheme JULES (Cox, 1998) that is able to evaluate the interaction between growing crops and the environment at large scales for a wide range of atmospheric conditions. JULES was designed to simulate land surface processes in natural ecosystems. The importance of representing agricultural land within global biosphere models has been pointed out in many studies (De Noblet-Ducoudre et al., 2004; Bondeau 2005 et al.). Prior to any model development, the sensitivity of JULES to morphological and physiological differences between natural vegetation and crops has been investigated by reparameterising a natural C3 grass into a C3 crop. For a case study of fallow versus wheat at Grignon (France), the model output shows important soil water savings after crop harvest at the beginning of the summer. Owing to the lack of a rooting system, the deeper soil moisture cannot contribute anymore to the moisture flux to the atmosphere. On a shorter timescale, the harvest, and by consequence the sudden appearance of bare soil, also disrupt the energy and momentum fluxes between surface and atmosphere. Having established the sensitivity of the JULES system to a crop-like forcing, some components from the crop model SUCROS (Goudriaan and van Laar, 1994) that are relevant to the global water, energy and carbon cycles, have been introduced in JULES. The new version of JULES, denoted by JULES-SUCROS, incorporates crops and natural vegetation within a single modelling framework, without discontinuity in the photosynthesis-assimilation scheme between both vegetation types. Simulations have been performed with JULES-SUCROS for wheat at the Grignon site in current and doubled CO2 atmospheric conditions. Changing atmospheric conditions in JULES-SUCROS affects the sowing date and the length of the growing season. The results show that the positive effect of the CO2 fertilisation partly

  14. Effects of crop management, soil type, and climate on N2O emissions from Austrian Soils

    NASA Astrophysics Data System (ADS)

    Zechmeister-Boltenstern, Sophie; Sigmund, Elisabeth; Kasper, Martina; Kitzler, Barbara; Haas, Edwin; Wandl, Michael; Strauss, Peter; Poetzelsberger, Elisabeth; Dersch, Georg; Winiwarter, Wilfried; Amon, Barbara

    2015-04-01

    Within the project FarmClim ("Farming for a better climate") we assessed recent N2O emissions from two selected regions in Austria. Our aim was to deepen the understanding of Austrian N2O fluxes regarding region specific properties. Currently, N2O emissions are estimated with the IPCC default emission factor which only considers the amount of N-input as an influencing factor for N2O emissions. We evaluated the IPCC default emission factor for its validity under spatially distinct environmental conditions. For this two regions for modeling with LandscapeDNDC have been identified in this project. The benefit of using LandscapeDNDC is the detailed illustration of microbial processes in the soil. Required input data to run the model included daily climate data, vegetation properties, soil characteristics and land management. The analysis of present agricultural practices was basis for assessing the hot spots and hot moments of nitrogen emissions on a regional scale. During our work with LandscapeDNDC we were able to adapt specific model algorithms to Austrian agricultural conditions. The model revealed a strong dependency of N2O emissions on soil type. We could estimate how strongly soil texture affects N2O emissions. Based on detailed soil maps with high spatial resolution we calculated region specific contribution to N2O emissions. Accordingly we differentiated regions with deviating gas fluxes compared to the predictions by the IPCC inventory methodology. Taking region specific management practices into account (tillage, irrigation, residuals) calculation of crop rotation (fallow, catch crop, winter wheat, barley, winter barley, sugar beet, corn, potato, onion and rapeseed) resulted in N2O emissions differing by a factor of 30 depending on preceding crop and climate. A maximum of 2% of N fertilizer input was emitted as N2O. Residual N in the soil was a major factor stimulating N2O emissions. Interannual variability was affected by varying N-deposition even in case

  15. Regional crop productivity and greenhouse gas emissions from Swiss soils under organic farming

    NASA Astrophysics Data System (ADS)

    Lee, Juhwan; Necpalova, Magdalena; Six, Johan

    2016-04-01

    There is worldwide concern about the increase in atmospheric greenhouse gases (GHG) and their impact on climate change and food security. As a sustainable alternative, organic cropping in various forms has been promoted to minimize the environmental impacts of conventional practices. However, relatively little is known about the potential to reduce GHG emissions while maintaining crop productivity through the large-scale adoption of organic practices. Therefore, we simulated and compared regional crop production, soil organic carbon status, and net soil GHG emissions under organic and conventional practices. Grid-level (2.2 km by 2.2 km) simulation was performed using previously validated DailyDayCent by considering typical crop rotations. Regional model estimates are presented and discussed specifically with the focus on Swiss organic and conventional cropping systems, which differ by type and intensity of manuring, tillage, and cover crop.

  16. Field scale spatio-temporal soil moisture variability for trafficability and crop water availability

    NASA Astrophysics Data System (ADS)

    Carranza, Coleen; van der Ploeg, Martine; Ritsema, Coen

    2016-04-01

    Spatio-temporal patterns of soil moisture have been studied mostly for inputs in land surface models for weather and climate predictions. Remote sensing techniques for estimation of soil moisture have been explored because of the good spatial coverage at different scales. Current available satellite data provide surface soil moisture as microwave systems only measure soil moisture content up to 5cm soil depth. The OWAS1S project will focus on estimation of soil moisture from freely available Sentinel-1 datasets for operational water management in agricultural areas. As part of the project, it is essential to develop spatio-temporal methods to estimate root zone soil moisture from surface soil moisture. This will be used for crop water availability and trafficability in selected agricultural fields in the Netherlands. A network of single capacitance sensors installed per field will provide continuous measurements of soil moisture in the study area. Ground penetrating radar will be used to measure soil moisture variability within a single field for different time periods. During wetter months, optimal conditions for traffic will be assessed using simultaneous soil strength and soil moisture measurements. Towards water deficit periods, focus is on the relation (or the lack thereof) between surface soil moisture and root zone soil moisture to determine the amount of water for crops. Spatio-temporal distribution will determine important physical controls for surface and root zone soil moisture and provide insights for root-zone soil moisture. Existing models for field scale soil-water balance and data assimilation methods (e.g. Kalman filter) will be combined to estimate root zone soil moisture. Furthermore, effects of root development on soil structure and soil hydraulic properties and subsequent effects on trafficability and crop water availability will be investigated. This research project has recently started, therefore we want to present methods and framework of

  17. Long-term Annual No-Till Cropping in Washington’s Winter Wheat – Summer Fallow Region

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The tillage-based winter wheat – summer fallow (WW-SF) cropping system has dominated dryland farming in the Pacific Northwest for 125 years. We conducted a large-scale multidisciplinary 8-year study of annual no-till cropping systems as an alternative to WW-SF. Soft white and hard white classes of w...

  18. Spatial and temporal heterogeneity of water soil erosion in a Mediterranean rain-fed crop

    NASA Astrophysics Data System (ADS)

    López-Vicente, M.; Quijano, L.; Gaspar, L.; Machín, J.; Navas, A.

    2012-04-01

    value of 72.23 Mg / ha yr, whereas the grass and forested areas have annual rates lower than 0.1 Mg / ha yr. The highest values of soil erosion appear in March, April, May, October and November showing a very good correlation with the depth of monthly rainfall (Pearson's r = 0.97) and a good correlation with the number of rainy days per month (Pearson's r = 0.76). However, no correlation was obtained with the values of monthly rainfall intensity. The availability of a detailed database of soil properties, weather values and a high resolution DEM allows mapping and calculating the spatial and temporal variations of the soil erosion processes within the cultivated area and the area surrounding the crop. Thus, the application of soil erosion models at high spatial and temporal resolution improves their predicting capability due to the complexity and large number of relevant interactions between the different sub-factors.

  19. Effect of long-term phosphorus fertilization on soil Se and transfer of soil Se to crops in northern Japan.

    PubMed

    Altansuvd, Javkhlantuya; Nakamaru, Yasuo M; Kasajima, Shinya; Ito, Hirotake; Yoshida, Hozumi

    2014-07-01

    Phosphorus (P) fertilizer can potentially serve as a source for Se accumulation in croplands. Furthermore, it has been reported that the addition of P fertilizer to soil may enhance Se availability. Japanese agricultural soils are typically enriched in P as a result of long-term, excessive P fertilization. Therefore, we conducted a three-year field experiment in order to evaluate the effect of P fertilization on the Se content of soils and crops. Potato, wheat and barley were cultivated with and without P fertilization at two field sites in Hokkaido (northern Japan) with different levels of historical P accumulation. The first field site consisted of an Andosol soil with low available P and the second site, a Cambisol soil with high available P. The three years of continuous P fertilization over the course of the experiment did not result in a significant increase in the Se content of soils or plants. The Se content of soils and plants, however, was higher in soil samples from the Cambisol field site than from the Andosol field site, and total soil Se was significantly correlated with available soil P. Soluble soil Se and the soil-plant transfer factor for Se were not affected by P fertilization. Thus, we concluded that the higher plant Se content at the Cambisol field site was primarily due to the higher levels of accumulated Se in the soil at the site and that historical excess P fertilization typical of agricultural soils in Japan contributes to increased Se uptake by crops.

  20. Soil and rainfall factors influencing yields of a dryland cropping system in Colorado

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The semi-arid Great Plains of the United States experience a large variation in crop yields due to variability in rainfall, soil, and other factors. We analyzed crop yields (24-year period) from a no-till rotation of wheat(Triticum aestivum)-corn (Zea mays L.) or sorghum[Sorghum bicolor (L.) Moench]...

  1. Projected irrigation requirements for upland crops using soil moisture model under climate change in South Korea

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An increase in abnormal climate change patterns and unsustainable irrigation in uplands cause drought and affect agricultural water security, crop productivity, and price fluctuations. In this study, we developed a soil moisture model to project irrigation requirements (IR) for upland crops under cl...

  2. Soil nitrate and forage yields of corn grown with clover or grass companion crops and manure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Few studies have compared the agronomic performance of cover crop and living mulch systems for no-till silage corn (Zea mays L.). In a four-year Wisconsin study, we compared soil nitrate levels, dry matter yields (DMY) and crude protein yields (CPY) from five such corn-companion crop systems amended...

  3. The impact of fall cover crops on soil nitrate and corn growth

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Incorporating cover crops into current production systems can have many beneficial impacts on the current cropping system including decreasing erosion, improving water infiltration, increasing soil organic matter and biological activity but in water limited areas caution should be utilized. A fiel...

  4. Cropping Intensity Impacts on Soil Aggregation and Carbon Sequestration in the Central Great Plains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The predominant cropping system in the Central Great Plains is conventional tillage (CT) winter wheat–summer fallow. We investigated the effect 15 yrs of variable cropping intensity, fallow frequency, and tillage (CT and no-till [NT]) had on soil organic C (SOC) sequestration, particulate organic ma...

  5. Cover Crop and Liquid Manure Effects on Soil Quality Indicators in a Corn Silage System.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Due to a lack of surface residue and organic matter inputs, continuous corn (Zea mays L.) silage production is one of the most demanding cropping systems imposed on our soil resources. In this study, our objective was to determine if using cover/companion crops and/or applying low-solids liquid dair...

  6. Soil profile organic carbon as affected by tillage and cropping systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Reports on the long-term effects of tillage and cropping systems on soil organic carbon (SOC) sequestration in the entire rooting profile are limited. A long-term experiment with three cropping systems [continuous corn (CC), continuous soybean (CSB), and soybean-corn (SB-C)] in six primary tillage s...

  7. Impact of climate, vegetation, soil and crop management variables on multi-year ISBA-A-gs simulations of evapotranspiration over a Mediterranean crop site

    NASA Astrophysics Data System (ADS)

    Garrigues, S.; Olioso, A.; Carrer, D.; Decharme, B.; Calvet, J.-C.; Martin, E.; Moulin, S.; Marloie, O.

    2015-10-01

    Generic land surface models are generally driven by large-scale data sets to describe the climate, the soil properties, the vegetation dynamic and the cropland management (irrigation). This paper investigates the uncertainties in these drivers and their impacts on the evapotranspiration (ET) simulated from the Interactions between Soil, Biosphere, and Atmosphere (ISBA-A-gs) land surface model over a 12-year Mediterranean crop succession. We evaluate the forcing data sets used in the standard implementation of ISBA over France where the model is driven by the SAFRAN (Système d'Analyse Fournissant des Renseignements Adaptés à la Nivologie) high spatial resolution atmospheric reanalysis, the leaf area index (LAI) time courses derived from the ECOCLIMAP-II land surface parameter database and the soil texture derived from the French soil database. For climate, we focus on the radiations and rainfall variables and we test additional data sets which include the ERA-Interim (ERA-I) low spatial resolution reanalysis, the Global Precipitation Climatology Centre data set (GPCC) and the MeteoSat Second Generation (MSG) satellite estimate of downwelling shortwave radiations. The evaluation of the drivers indicates very low bias in daily downwelling shortwave radiation for ERA-I (2.5 W m-2) compared to the negative biases found for SAFRAN (-10 W m-2) and the MSG satellite (-12 W m-2). Both SAFRAN and ERA-I underestimate downwelling longwave radiations by -12 and -16 W m-2, respectively. The SAFRAN and ERA-I/GPCC rainfall are slightly biased at daily and longer timescales (1 and 0.5 % of the mean rainfall measurement). The SAFRAN rainfall is more precise than the ERA-I/GPCC estimate which shows larger inter-annual variability in yearly rainfall error (up to 100 mm). The ECOCLIMAP-II LAI climatology does not properly resolve Mediterranean crop phenology and underestimates the bare soil period which leads to an overall overestimation of LAI over the crop succession. The

  8. Spatial variation of corn canopy temperature as dependent upon soil texture and crop rooting characteristics

    NASA Technical Reports Server (NTRS)

    Choudhury, B. J.

    1983-01-01

    A soil plant atmosphere model for corn (Zea mays L.) together with the scaling theory for soil hydraulic heterogeneity are used to study the sensitivity of spatial variation of canopy temperature to field averaged soil texture and crop rooting characteristics. The soil plant atmosphere model explicitly solves a continuity equation for water flux resulting from root water uptake, changes in plant water storage and transpirational flux. Dynamical equations for root zone soil water potential and the plant water storage models the progressive drying of soil, and day time dehydration and night time hydration of the crop. The statistic of scaling parameter which describes the spatial variation of soil hydraulic conductivity and matric potential is assumed to be independent of soil texture class. The field averaged soil hydraulic characteristics are chosen to be representative of loamy sand and clay loam soils. Two rooting characteristics are chosen, one shallow and the other deep rooted. The simulation shows that the range of canopy temperatures in the clayey soil is less than 1K, but for the sandy soil the range is about 2.5 and 5.0 K, respectively, for the shallow and deep rooted crops.

  9. C and N accumulations in soil aggregates determine nitrous oxide emissions from cover crop treated rice paddy soils during fallow season.

    PubMed

    Pramanik, Prabhat; Haque, Md Mozammel; Kim, Sang Yoon; Kim, Pil Joo

    2014-08-15

    Combination of leguminous and non-leguminous plant residues are preferably applied in rice paddy soils to increase the rate of organic matter mineralization and to improve plant growth. However, organic matter addition facilitates methane (CH4) emission from rice paddy soil. Mineralization of organic nitrogen (N) increases NO3-N concentrations in soil, which are precursors for the formation of nitrous oxide (N2O). However, N2O is a minor greenhouse gas emitted from submerged rice field and hence is not often considered during calculation of total global warming potential (GWP) during rice cultivation. The hypothesis of this study was that fluxes of N2O emissions might be changed after removal of flooded water from rice field and the effect of cover crops on N2O emissions in the fallow season might be interesting. However, the effects of N-rich plant residues on N2O emission rates in the fallow season and its effect on annual GWP were not studied before. In this experiment, combination of barley (non-leguminous) and hairy vetch (leguminous) biomasses were applied at 9 Mg ha(-1) and 27 Mg ha(-1) rates in rice paddy soil. Cover crop application significantly increased CH4 emission flux while decreased N2O emissions during rice cultivation. The lowest N2O emission was observed in 27 Mg ha(-1) cover crop treated plots. Cover crop applications increased N contents in soil aggregates especially in smaller aggregates (<250 μm), and that proportionately increased the N2O emission potentials of these soil aggregates. Fluxes of N2O emissions in the fallow season were influenced by the N2O emission potentials of soil aggregates and followed opposite trends as those observed during rice cultivation. Therefore, it could be concluded that the doses of cover crop applications for rice cultivation should not be optimized considering only CH4, but N2O should also be considered especially for fallow season to calculate total GWP.

  10. Machine-assisted analysis of Landsat data in the study of crop-soils relationships

    USGS Publications Warehouse

    Draeger, William C.

    1976-01-01

    To date, relatively few studies have dealt with crop-soil interactions as they affect the appearance of agricultural areas on Landsatimagery, and hence crop and soil classification or the analysis of agricultural land use.The Image 100, a computer-based data analysis system which allows an interpreter to interact directly and rapidly with Landsat computercompatible tape data, provided a tool to assist in the evaluation of the extent and significance of these interactions. Used with timely and accurate ground data, the system made possible a determination of the variability in crop spectral appearance, from soil type to soil type, as recorded on Landsat data. Information was provided in the form of spectral distribution histrograms for each crop-soil class on each Landsat band. Several crop categories in a test area in Brookings County, South Dakota, were classified using training fields that were selected to be representative of each major crop-soil class. Accuracies in each case, on a total acreage basis, were greater than 90 percent.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  12. Crop yield and soil organic carbon in conventional and no-till organic systems on a claypan soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organic crop production is dependent on tillage for weed control, but because tillage can lead to decreased levels of soil organic carbon (SOC), alternative management needs to be explored. This study was conducted in Boone County, MO in a Mexico silt loam soil (fine, smectitic, mesic Vertic Epiaqua...

  13. Changes in Soil Moisture, Microbial Biomass, Mineralization and Nitrification Explain Increases in N2O Emissions from a Spring Barley Crop Under Combined Reduced Tillage and Cover Crop Management

    NASA Astrophysics Data System (ADS)

    Rueangritsarakul, K.; Jones, M.; Roth, B.; Abdalla, M.; Williams, M.

    2012-04-01

    This study investigated the effect of conventional tillage (CT), combined reduced tillage-cover crop (RT-CC), and reduced N application on crop yield and N2O emissions from spring barley. Reduced tillage plots were established for seven years, the final four incorporating a mustard cover crop. Higher N2O fluxes were from fertilized, RT-CC plots due to higher WFPS, soil nitrate, and soil carbon. Fluxes during the non-growing season were variable and the main source of cumulative emissions. Emission factors were in the range of IPCC default values. Low N fertilization reduced cumulative emissions, however during the wetter growing season this reduction was smaller than the reduction in barley production particular in the conventional tillage plots. Adopting RT-CC management for cereal crops may be problematic in reducing GHG emissions due to high N2O fluxes. Reducing N fertilizer in order to reduce N2O emissions is not feasible due to high inter-annual variation in crop yield. N2O flux in all plots was positively correlated with microbial biomass carbon, net nitrification and mineralization determined in the field. Increased emissions of N2O in the RT-CC plots are accounted for by increases in organic carbon in the soil and increases in mineralization.

  14. Reduced tillage intensity and incidence of fallow combined with crop rotation improves soil quality in the Great Plains.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soils perform essential functions related to storing and filtering water, cycling nutrients, and serving as a substrate for crop growth. Management practices are known to effect soil function. A multi-location study was conducted to compare traditional cropping systems to alternative cropping system...

  15. [Fungal population structure and its biological effect in rhizosphere soil of continuously cropped potato].

    PubMed

    Meng, Pin-Pin; Liu, Xing; Qiu, Hui-Zhen; Zhang, Wen-Ming; Zhang, Chun-Hong; Wang, Di; Zhang, Jun-Lian; Shen, Qi-Rong

    2012-11-01

    Continuous cropping obstacle is one of the main restriction factors in potato industry. In order to explore the mechanisms of potato's continuous cropping obstacle and to reduce the impact on potato's tuber yield, a field experiment combined with PCR-DGGE molecular fingerprinting was conducted to investigate the fungal population structure and its biological effect in rhizosphere soil of continuously cropped potato. With the increasing year of potato' s continuous cropping, the numbers of visible bands in rhizosphere fungal DGGE profiles increased obviously. As compared with that of CK (rotation cropping), the operational taxonomic unit (OTU) in treatments of one to five years continuous cropping was increased by 38.5%, 38.5%, 30.8%, 46.2%, and 76.9% respectively, indicating that potato's continuous cropping caused an obvious increase in the individual numbers of dominant fungal populations in rhizosphere soil. Also with the increasing year of potato's continuous cropping, the similarity of the fungal population structure among the treatments had a gradual decrease. The sequencing of the fungal DGGE bands showed that with the increasing year of continuous cropping, the numbers of the potato's rhizosphere soil-borne pathogens Fusarium oxysporum and F. solani increased obviously, while the number of Chaetomium globosum, as a biocontrol species, had a marked decrease in the fifth year of continuous cropping. It was suggested that potato' s continuous cropping caused the pathogen fungal populations become the dominant microbial populations in rhizosphere soil, and the rhizosphere micro-ecological environment deteriorated, which in turn affected the root system, making the root vigor and its absorption area reduced, and ultimately, the tuber yield decreased markedly.

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

    PubMed

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

    2015-07-01

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

  17. [Effects of nutrition medium on cucumber growth and soil microenvironment in greenhouse under continuous cropping].

    PubMed

    Wu, Chun-Cheng; Li, Tian-Lai; Cao, Xia; Meng, Si-Da; Zhang, Yong-Yong; Yang, Li-Juan

    2014-05-01

    An experiment of continuous cropping of cucumber in nutrition medium (composted with straw, rural soil and puffed chicken manure) or soil was conducted in greenhouse in order to study the effects of medium type on the cucumber growth and soil microenvironment, respectively. The results showed that the two treatments both displayed different levels of obstacles resulted from continuous cropping. In the same cropping season, the nutrient content, soil invertase and urease activities and B/F (bacteria/fungi) ratio in the nutrition medium were obviously higher but fungi quantity was lower than in the soil medium, suggesting the use of nutrition medium changed the bacterial population structure as to improve the cucumber growth and yield. Under continuous cropping, correlation analysis showed that the bacterial quantity was significantly positively related with plant height and root dry mass, and markedly significantly positive correlation exited between the aboveground dry mass and yield of cucumber. The urease activity was also significantly positively related with the cucumber yield. Compared with the soil medium, the nutrition medium could greatly improve soil microenvironment and alleviate the continuous cropping obstacle.

  18. Managing soil nitrate with cover crops and buffer strips in Sicilian vineyards

    NASA Astrophysics Data System (ADS)

    Novara, A.; Gristina, L.; Guaitoli, F.; Santoro, A.; Cerdà, A.

    2013-08-01

    When soil nitrate levels are low, plants suffer nitrogen (N) deficiency but when the levels are excessive, soil nitrates can pollute surface and subsurface waters. Strategies to reduce the nitrate pollution are necessary to reach a sustainable use of resources such as soil, water and plant. Buffer strips and cover crops can contribute to the management of soil nitrates, but little is known of their effectiveness in semiarid vineyards plantations. The research was carried out in the south coast of Sicily (Italy) to evaluate nitrate trends in a vineyard managed both conventionally and using two different cover crops (Triticum durum and Vicia sativa cover crop). A 10 m-wide buffer strip was seeded with Lolium perenne at the bottom of the vineyard. Soil nitrate was measured monthly and nitrate movement was monitored by application of a 15N tracer to a narrow strip between the bottom of vineyard and the buffer and non-buffer strips. Lolium perenne biomass yield in the buffer strips and its isotopic nitrogen content were monitored. Vicia sativa cover crop management contributed with an excess of nitrogen, and the soil management determined the nitrogen content at the buffer areas. A 6 m buffer strip reduced the nitrate by 42% with and by 46% with a 9 m buffer strip. Thanks to catch crops, farmers can manage the N content and its distribution into the soil over the year, can reduced fertilizer wastage and reduce N pollution of surface and groundwater.

  19. Detecting crop yield reduction due to irrigation-induced soil salinization in South-West Russia

    NASA Astrophysics Data System (ADS)

    Argaman, E.; Beets, W.; Croes, J.; Keesstra, S.; Verzandvoort, S.; Zeiliguer, A.

    2012-04-01

    The South-European part of the Russian Federation has experienced serious land degradation in the form of soil salinization since the 1960s. This land degradation was caused by intensive, large-scale irrigation on reclaimed land in combination with the salt-rich nature of the substrate. Alkaline soil salinity is believed to be an important factor decreasing crop yield in this area. A large research effort has been directed to the effects of soil salinity on crops, there is a need for simple, easily determinable indicators of crop health and soil salinity in irrigated systems, that can help to detect crop water stress in an early stage. The objectives of this research were to study the effects of soil salinity and vegetation water stress on the performance of alfalfa crop yield and physiological crop properties, and to study the possibility to measure soil salinity and alkalinity and the crop water stress index at plot level using a thermal gun and a regular digital camera. The study area was located in Saratov District, in the South-West part of Russia. Variables on the surface energy balance, crop properties, soil properties and visible reflectance were measured on plots with alfalfa cultures in two fields with and without signs of alkaline soil salinity, and with and without irrigation in July 2009. The research showed no clear adverse effects of soil salinity and soil alkalinity on crop yield and physiological crop properties. Soil salinity, as reflected by the electric conductivity, positively affected the root biomass of alfalfa in the range of 0.15 to 1.52 dS/m . This was a result of EC levels being below the documented threshold to negatively affect Alfalfa, as would be the case in truly saline soils. The soil pH also showed a positive correlation with root biomass within the range of pH 6.2 and 8.5 . From the literature these pH values are generally believed to be too high to exhibit a positive relationship with root biomass. No relationship was found

  20. Anaerobic Soil Disinfestation For Florida Specialty Crop Production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anaerobic soil disinfestation (ASD) is a process in which organic amendments are applied to soil, covered with a polyethylene film, and saturated with water to create conditions conducive for soil bacteria to deplete oxygen levels and generate organic acids in soil. The generation of acids and re...

  1. Does grazing of cover crops impact biologically active soil C and N fractions under inversion and no tillage management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cover crops are a key component of conservation cropping systems. They can also be a key component of integrated crop-livestock systems by offering high-quality forage during short periods between cash crops. The impact of cattle grazing on biologically active soil C and N fractions has not receiv...

  2. Soil Functional Zone Management: A Vehicle for Enhancing Production and Soil Ecosystem Services in Row-Crop Agroecosystems

    PubMed Central

    Williams, Alwyn; Kane, Daniel A.; Ewing, Patrick M.; Atwood, Lesley W.; Jilling, Andrea; Li, Meng; Lou, Yi; Davis, Adam S.; Grandy, A. Stuart; Huerd, Sheri C.; Hunter, Mitchell C.; Koide, Roger T.; Mortensen, David A.; Smith, Richard G.; Snapp, Sieglinde S.; Spokas, Kurt A.; Yannarell, Anthony C.; Jordan, Nicholas R.

    2016-01-01

    There is increasing global demand for food, bioenergy feedstocks and a wide variety of bio-based products. In response, agriculture has advanced production, but is increasingly depleting soil regulating and supporting ecosystem services. New production systems have emerged, such as no-tillage, that can enhance soil services but may limit yields. Moving forward, agricultural systems must reduce trade-offs between production and soil services. Soil functional zone management (SFZM) is a novel strategy for developing sustainable production systems that attempts to integrate the benefits of conventional, intensive agriculture, and no-tillage. SFZM creates distinct functional zones within crop row and inter-row spaces. By incorporating decimeter-scale spatial and temporal heterogeneity, SFZM attempts to foster greater soil biodiversity and integrate complementary soil processes at the sub-field level. Such integration maximizes soil services by creating zones of ‘active turnover’, optimized for crop growth and yield (provisioning services); and adjacent zones of ‘soil building’, that promote soil structure development, carbon storage, and moisture regulation (regulating and supporting services). These zones allow SFZM to secure existing agricultural productivity while avoiding or minimizing trade-offs with soil ecosystem services. Moreover, the specific properties of SFZM may enable sustainable increases in provisioning services via temporal intensification (expanding the portion of the year during which harvestable crops are grown). We present a conceptual model of ‘virtuous cycles’, illustrating how increases in crop yields within SFZM systems could create self-reinforcing feedback processes with desirable effects, including mitigation of trade-offs between yield maximization and soil ecosystem services. Through the creation of functionally distinct but interacting zones, SFZM may provide a vehicle for optimizing the delivery of multiple goods and services

  3. Soil Functional Zone Management: A Vehicle for Enhancing Production and Soil Ecosystem Services in Row-Crop Agroecosystems.

    PubMed

    Williams, Alwyn; Kane, Daniel A; Ewing, Patrick M; Atwood, Lesley W; Jilling, Andrea; Li, Meng; Lou, Yi; Davis, Adam S; Grandy, A Stuart; Huerd, Sheri C; Hunter, Mitchell C; Koide, Roger T; Mortensen, David A; Smith, Richard G; Snapp, Sieglinde S; Spokas, Kurt A; Yannarell, Anthony C; Jordan, Nicholas R

    2016-01-01

    There is increasing global demand for food, bioenergy feedstocks and a wide variety of bio-based products. In response, agriculture has advanced production, but is increasingly depleting soil regulating and supporting ecosystem services. New production systems have emerged, such as no-tillage, that can enhance soil services but may limit yields. Moving forward, agricultural systems must reduce trade-offs between production and soil services. Soil functional zone management (SFZM) is a novel strategy for developing sustainable production systems that attempts to integrate the benefits of conventional, intensive agriculture, and no-tillage. SFZM creates distinct functional zones within crop row and inter-row spaces. By incorporating decimeter-scale spatial and temporal heterogeneity, SFZM attempts to foster greater soil biodiversity and integrate complementary soil processes at the sub-field level. Such integration maximizes soil services by creating zones of 'active turnover', optimized for crop growth and yield (provisioning services); and adjacent zones of 'soil building', that promote soil structure development, carbon storage, and moisture regulation (regulating and supporting services). These zones allow SFZM to secure existing agricultural productivity while avoiding or minimizing trade-offs with soil ecosystem services. Moreover, the specific properties of SFZM may enable sustainable increases in provisioning services via temporal intensification (expanding the portion of the year during which harvestable crops are grown). We present a conceptual model of 'virtuous cycles', illustrating how increases in crop yields within SFZM systems could create self-reinforcing feedback processes with desirable effects, including mitigation of trade-offs between yield maximization and soil ecosystem services. Through the creation of functionally distinct but interacting zones, SFZM may provide a vehicle for optimizing the delivery of multiple goods and services in

  4. Structure of bacterial communities in soil following cover crop and organic fertilizer incorporation.

    PubMed

    Fernandez, Adria L; Sheaffer, Craig C; Wyse, Donald L; Staley, Christopher; Gould, Trevor J; Sadowsky, Michael J

    2016-11-01

    Incorporation of organic material into soils is an important element of organic farming practices that can affect the composition of the soil bacterial communities that carry out nutrient cycling and other functions crucial to crop health and growth. We conducted a field experiment to determine the effects of cover crops and fertilizers on bacterial community structure in agricultural soils under long-term organic management. Illumina sequencing of 16S rDNA revealed diverse communities comprising 45 bacterial phyla in corn rhizosphere and bulk field soil. Community structure was most affected by location and by the rhizosphere effect, followed by sampling time and amendment treatment. These effects were associated with soil physicochemical properties, including pH, moisture, organic matter, and nutrient levels. Treatment differences were apparent in bulk and rhizosphere soils at the time of peak corn growth in the season following cover crop and fertilizer application. Cover crop and fertilizer treatments tended to lower alpha diversity in early season samples. However, winter rye, oilseed radish, and buckwheat cover crop treatments increased alpha diversity in some later season samples compared to a no-amendment control. Fertilizer treatments and some cover crops decreased relative abundance of members of the ammonia-oxidizing family Nitrosomonadaceae. Pelleted poultry manure and Sustane® (a commercial fertilizer) decreased the relative abundance of Rhizobiales. Our data point to a need for future research exploring how (1) cover crops influence bacterial community structure and functions, (2) these effects differ with biomass composition and quantity, and (3) existing soil conditions and microbial community composition influence how soil microbial populations respond to agricultural management practices.

  5. Impact of Location, Cropping History, Tillage, and Chlorpyrifos on Soil Arthropods in Peanut.

    PubMed

    Cardoza, Yasmin J; Drake, Wendy L; Jordan, David L; Schroeder-Moreno, Michelle S; Arellano, Consuelo; Brandenburg, Rick L

    2015-08-01

    Demand for agricultural production systems that are both economically viable and environmentally conscious continues to increase. In recent years, reduced tillage systems, and grass and pasture rotations have been investigated to help maintain or improve soil quality, increase crop yield, and decrease labor requirements for production. However, documentation of the effects of reduced tillage, fescue rotation systems as well as other management practices, including pesticides, on pest damage and soil arthropod activity in peanut production for the Mid-Atlantic US region is still limited. Therefore, this project was implemented to assess impacts of fescue-based rotation systems on pests and other soil organisms when compared with cash crop rotation systems over four locations in eastern North Carolina. In addition, the effects of tillage (strip vs. conventional) and soil chlorpyrifos application on pod damage and soil-dwelling organisms were also evaluated. Soil arthropod populations were assessed by deploying pitfall traps containing 50% ethanol in each of the sampled plots. Results from the present study provide evidence that location significantly impacts pest damage and soil arthropod diversity in peanut fields. Cropping history also influenced arthropod diversity, with higher diversity in fescue compared with cash crop fields. Corn rootworm damage to pods was higher at one of our locations (Rocky Mount) compared with all others. Cropping history (fescue vs. cash crop) did not have an effect on rootworm damage, but increased numbers of hymenopterans, acarina, heteropterans, and collembolans in fescue compared with cash crop fields. Interestingly, there was an overall tendency for higher number of soil arthropods in traps placed in chlorpyrifos-treated plots compared with nontreated controls.

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

    NASA Astrophysics Data System (ADS)

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

    2015-04-01

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

  7. Effect of crop residue incorporation on soil organic carbon (SOC) and greenhouse gas (GHG) emissions in European agricultural soils

    NASA Astrophysics Data System (ADS)

    Lehtinen, Taru; Schlatter, Norman; Baumgarten, Andreas; Bechini, Luca; Krüger, Janine; Grignani, Carlo; Zavattaro, Laura; Costamagna, Chiara; Spiegel, Heide

    2014-05-01

    Soil organic matter (SOM) improves soil physical (e.g. increased aggregate stability), chemical (e.g. cation exchange capacity) and biological (e.g. biodiversity, earthworms) properties. The sequestration of soil organic carbon (SOC) may mitigate climate change. However, as much as 25-75% of the initial SOC in world agricultural soils may have been lost due to intensive agriculture (Lal, 2013). The European Commission has described the decline of organic matter (OM) as one of the major threats to soils (COM(2006) 231). Incorporation of crop residues may be a sustainable and cost-efficient management practice to maintain the SOC levels and to increase soil fertility in European agricultural soils. Especially Mediterranean soils that have low initial SOC concentrations, and areas where stockless croplands predominate may be suitable for crop residue incorporation. In this study, we aim to quantify the effects of crop residue incorporation on SOC and GHG emissions (CO2 and N2O) in different environmental zones (ENZs, Metzger et al., 2005) in Europe. Response ratios for SOC and GHG emissions were calculated from pairwise comparisons between crop residue incorporation and removal. Specifically, we investigated whether ENZs, clay content and experiment duration influence the response ratios. In addition, we studied how response ratios of SOM and crop yields were correlated. A total of 718 response ratios (RR) were derived from a total of 39 publications, representing 50 experiments (46 field and 4 laboratory) and 15 countries. The SOC concentrations and stocks increased by approximately 10% following crop residue incorporation. In contrast, CO2 emissions were approximately six times and N2O emissions 12 times higher following crop residue incorporation. The effect of ENZ on the response ratios was not significant. For SOC concentration, the >35% clay content had significantly approximately 8% higher response ratios compared to 18-35% clay content. As the duration of the

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2016-11-01

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

  10. Erosion control in orchards and vineyards by a new soil and cover crop management method

    NASA Astrophysics Data System (ADS)

    Hartl, Wilfried; Guettler, Hans; Auer, Karl; Erhart, Eva

    2016-04-01

    Cover crops are the basis for an erosion-free soil management in orchards and vineyards. The soil cover provided by the foliage and the intensive root formation counteract erosion. Cover crops provide the soil microfauna with fresh organic matter which improves soil structure and porosity. The water demand of cover crops, however, may pose problems for the water supply of the trees and vines in dry seasons. Therefore it is necessary to adjust the growth of the cover crops to the actual water conditions. In years with ample precipitation cover crops may be allowed lush vegetative growth till flowering and formation of seeds. In dry years, the growth of the cover crop must be restricted to stop the competition for water, sometimes even by cutting off the cover crop roots. The course of the weather is incalculable and rainfall may be very variable during the year, so it is sometimes necessary to adust the cover crop management several times a year. A new special equipment, which can perform all the tasks necessary for the flexible cover crop management has been developed together with the agricultural machinery manufacturers Bodenwerkstatt Ertl-Auer GmbH and Güttler GmbH. The GreenManager® device consists of three modules, namely a specific type of cultivator, a harrow and a prismatic roller with seeding equipment, which can be used separately or in combination. The GreenManager® can reduce cover crops by flattening the plants in the whole row middle, by bringing down the cover crops with the harrow, or by horizontally cutting the cover crop roots a few centimetres beneath the soil surface in the central part of the row middle or in the whole row middle. These measures reduce the water competition by cover crops without generating further losses of soil moisture through intensive soil cultivation. At the same time the risk of soil erosion is kept to a minimum, because the soil remains covered by dead plant biomass. In one passage the GreenManager® can direct

  11. Salt and N leaching and soil accumulation due to cover cropping practices

    NASA Astrophysics Data System (ADS)

    Gabriel, J. L.; Quemada, M.

    2012-04-01

    Nitrate leaching beyond the root zone can increase water contamination hazards and decrease crop available N. Cover crops used in spite of fallow are an alternative to reduce nitrate contamination in the vadose zone, because reducing drainage and soil mineral N accumulation. Cover crops can improve important characteristics in irrigated land as water retention capacity or soil aggregate stability. However, increasing evapotranspiration and consequent drainage below the root system reduction, could lead to soil salt accumulation. Salinity affects more than 80 million ha of arable land in many areas of the world, and one of the principal causes for yield reduction and even land degradation in the Mediterranean region. Few studies dealt with both problems at the same time. Therefore, it is necessary a long-term evaluation of the potential effect on soil salinity and nitrate leaching, in order to ensure that potential disadvantages that could originate from soil salt accumulation are compensated with all advantages of cover cropping. A study of the soil salinity and nitrate leaching was conducted during 4 years in a semiarid irrigated agricultural area of Central Spain. Three treatments were studied during the intercropping period of maize (Zea mays L.): barley (Hordeum vulgare L.), vetch (Vicia villosa L.) and fallow. Cover crops were killed in March allowing seeding of maize of the entire trial in April, and all treatments were irrigated and fertilised following the same procedure. Before sowing, and after harvesting maize and cover crops, soil salt and nitrate accumulation was determined along the soil profile. Soil analysis was conducted at six depths every 0.20 m in each plot in samples from four 0 to 1.2-m depth holes dug. The electrical conductivity of the saturated paste extract and soil mineral nitrogen was measured in each soil sample. A numerical model based on the Richards water balance equation was applied in order to calculate drainage at 1.2 m depth

  12. Energy Crops and their Implications on Soil Carbon Sequestration, Surface Energy and Water Balance

    NASA Astrophysics Data System (ADS)

    Song, Y.; Barman, R.; Jain, A. K.

    2011-12-01

    The quest to meet growing energy demand with low greenhouse gas emissions has increased attention on the potential of existing and advanced biomass energy crops. Potential energy crops include row crops such as corn, and perennial grasses such as switchgrass. However, a massive expansion of bioenergy crops raises many questions such as: how and where to grow energy crops; and what will be the impacts of growing large scale biofuel crops on the terrestrial hydrological cycle, the surface energy budget, soil carbon sequestration and the concurrent effects on the climate system. An integrated modeling system is being developed with in the framework of a land surface model, the Integrated Science Assessment Model (ISAM), and being applied to address these questions.This framework accounts for the biophysical, physiological and biogeochemical systems governing important processes that regulate crop growth including water, energy and nutrient cycles within the soil-plant-atmosphere system. One row crop (Corn) and two energy crops (Switchgrass and Miscanthus) are studied in current framework. Dynamic phenology processes and parameters for simulating each crop have been developed using observed data from a north to south gradient of field trial sites. This study will specifically focus on the agricultural regions in the US and in Europe. The potential productivity of these three crops will be assessed in terms of carbon sequestration, surface energy and water balance and their spatial variability. This study will help to quantify the importance of various environmental aspects towards modeling bioenergy crops and to better understand the spatial and temporal dynamics of bioenergy crop yields.

  13. Water-saving ground cover rice production system reduces net greenhouse gas fluxes in an annual rice-based cropping system

    NASA Astrophysics Data System (ADS)

    Yao, Z.; Du, Y.; Tao, Y.; Zheng, X.; Liu, C.; Lin, S.; Butterbach-Bahl, K.

    2014-11-01

    To safeguard food security and preserve precious water resources, the technology of water-saving ground cover rice production system (GCRPS) is being increasingly adopted for rice cultivation. However, changes in soil water status and temperature under GCRPS may affect soil biogeochemical processes that control the biosphere-atmosphere exchanges of methane (CH4), nitrous oxide (N2O) and carbon dioxide (CO2). The overall goal of this study is to better understand how net ecosystem greenhouse gas exchanges (NEGE) and grain yields are affected by GCRPS in an annual rice-based cropping system. Our evaluation was based on measurements of the CH4 and N2O fluxes and soil heterotrophic respiration (CO2 emissions) over a complete year, and the estimated soil carbon sequestration intensity for six different fertilizer treatments for conventional paddy and GCRPS. The fertilizer treatments included urea application and no N fertilization for both conventional paddy (CUN and CNN) and GCRPS (GUN and GNN), and solely chicken manure (GCM) and combined urea and chicken manure applications (GUM) for GCRPS. Averaging across all the fertilizer treatments, GCRPS increased annual N2O emission and grain yield by 40 and 9%, respectively, and decreased annual CH4 emission by 69%, while GCRPS did not affect soil CO2 emissions relative to the conventional paddy. The annual direct emission factors of N2O were 4.01, 0.09 and 0.50% for GUN, GCM and GUM, respectively, and 1.52% for the conventional paddy (CUN). The annual soil carbon sequestration intensity under GCRPS was estimated to be an average of -1.33 Mg C ha-1 yr-1, which is approximately 44% higher than the conventional paddy. The annual NEGE were 10.80-11.02 Mg CO2-eq ha-1 yr-1 for the conventional paddy and 3.05-9.37 Mg CO2-eq ha-1 yr-1 for the GCRPS, suggesting the potential feasibility of GCRPS in reducing net greenhouse effects from rice cultivation. Using organic fertilizers for GCRPS considerably reduced annual emissions of CH4

  14. Water-saving ground cover rice production system reduces net greenhouse gas fluxes in an annual rice-based cropping system

    NASA Astrophysics Data System (ADS)

    Yao, Z.; Du, Y.; Tao, Y.; Zheng, X.; Liu, C.; Lin, S.; Butterbach-Bahl, K.

    2014-06-01

    To safeguard food security and preserve precious water resources, the technology of water-saving ground cover rice production system (GCRPS) is being increasingly adopted for the rice cultivation. However, changes in soil water status and temperature under GCRPS may affect soil biogeochemical processes that control the biosphere-atmosphere exchanges of methane (CH4), nitrous oxide (N2O) and carbon dioxide (CO2). The overall goal of this study is to better understand how net ecosystem greenhouse gas exchanges (NEGE) and grain yields are affected by GCRPS in an annual rice-based cropping system. Our evaluation was based on measurements of the CH4 and N2O fluxes and soil heterotrophic respiration (CO2 emission) over a complete year, as well as the estimated soil carbon sequestration intensity for six different fertilizer treatments for conventional paddy and GCRPS. The fertilizer treatments included urea application and no N fertilization for both conventional paddy (CUN and CNN) and GCRPS (GUN and GNN), solely chicken manure (GCM) and combined urea and chicken manure applications (GUM) for GCRPS. Averaging across all the fertilizer treatments, GCRPS increased annual N2O emission and grain yield by 40% and 9%, respectively, and decreased annual CH4 emission by 69%, while GCRPS did not affect soil CO2 emissions relative to the conventional paddy. The annual direct emission factors of N2O were 4.01, 0.087 and 0.50% for GUN, GCM and GUM, respectively, and 1.52% for the conventional paddy (CUN). The annual soil carbon sequestration intensity under GCRPS was estimated to be an average of -1.33 Mg C ha-1 yr-1, which is approximately 44% higher than the conventional paddy. The annual NEGE were 10.80-11.02 Mg CO2-eq ha-1 yr-1 for the conventional paddy and 3.05-9.37 Mg CO2-eq ha-1 yr-1 for the GCRPS, suggesting the potential feasibility of GCRPS in reducing net greenhouse effect from rice cultivation. Using organic fertilizers for GCRPS considerably reduced annual emissions

  15. Hyperspectral remote sensing estimation of crop residue cover: Soil mineralogy, surface conditions, and their effects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Conservation tillage practices can enhance soil organic carbon content (SOC), improve soil structure, and reduce erosion. However, direct assessment of tillage practice for monitoring SOC change over large regions is difficult. Remote sensing of crop residue cover (CRC) can help assess tillage pra...

  16. Multiple microbial activity-based measures reflect effects of cover cropping and tillage on soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural producers, conservation professionals, and policy makers are eager to learn of soil analytical techniques and data that document improvement in soil health by agricultural practices such as no-till and incorporation of cover crops. However, there is considerable uncertainty within the r...

  17. Enhancing Potato System Sustainability: Crop Rotation Impacts on Soil Phosphatase Activity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Potato is a species with a low efficiency of acquiring soil P. Rotation crops may potentially influence P uptake by potato by increasing soil organic acids, phosphatase activity, and microbial biomass. However, this kind of information is very limited. We measured the activities of acid phosphatase,...

  18. Mobile proximal soil sensing for crop productivity assessment and water management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil sensing shows promise for efficient crop water management. Most soil sensors used in irrigation management are in-situ devices that provide temporally dense data. However, they are generally deployed at only a few locations and therefore do not adequately characterize spatial variability in soi...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  20. Impacts of an integrated crop-livestock system on soil properties to enhance precipitation capture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cropping/Livestock systems alter soil properties that are important in enhancing capture of precipitation by developing and maintaining water infiltration and storage. In this paper we will relate soil hydraulic conductivity and other physical properties on managed Old World Bluestem grassland, whea...

  1. Soil heat flux calculation for sunlit and shaded surfaces under row crops: 2. Model Test

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A method to calculate surface soil heat flux (G0) as a function of net radiation to the soil (RN,S) was developed that accounts for positional variability across a row crop interrow. The method divides the interrow into separate sections, which may be shaded, partially sunlit, or fully sunlit, and c...

  2. Soil health, crop productivity, microbial transport, and mine spoil response to biochars

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biochar is being evaluated by scientists from the United States Department of Agriculture (USDA) Agricultural Research Service (ARS) for its potential to sequester soil C, to improve soil health, and to increase crop yields. ARS scientists from multiple locations such as Florence, SC, Kimberly, ID,...

  3. Ameliorating soil acidity of tropical Oxisols by liming for sustainable crop production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The greatest potential for expanding the world’s agricultural frontier lies in the savanna regions of the tropics, which are dominated by Oxisols. Soil acidity and low native fertility, however, are major constraints for crop production on tropical Oxisols. Soil acidification is an ongoing natural p...

  4. Remediation of Stratified Soil Acidity Through Surface Application of Lime in No-Till Cropping Systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yield reduction and reduced crop vigor, resulting from soil acidification, are of increasing concern in eastern Washington and northern Idaho. In this region, soil pH has been decreasing at an accelerated rate, primarily due to the long-term use of ammonium based fertilizers. In no-till systems, the...

  5. Effects of cover cropping on soil and rhizosphere microbial community structure in tomato production systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Black polyethylene film is frequently used in vegetable farming systems to promote rapid warming of the soil in spring, conserve soil moisture, and suppress weeds. Alternative systems have been developed using cover cropping with legumes to provide a weed-suppressive mulch while also fixing nitrogen...

  6. Dynamic succession of soil bacterial community during continuous cropping of peanut (Arachis hypogaea L.).

    PubMed

    Chen, Mingna; Li, Xiao; Yang, Qingli; Chi, Xiaoyuan; Pan, Lijuan; Chen, Na; Yang, Zhen; Wang, Tong; Wang, Mian; Yu, Shanlin

    2014-01-01

    Plant health and soil fertility are affected by plant-microbial interactions in soils. Peanut is an important oil crop worldwide and shows considerable adaptability, but growth and yield are negatively affected by continuous cropping. In this study, 16S rRNA gene clone library analyses were used to study the succession of soil bacterial communities under continuous peanut cultivation. Six libraries were constructed for peanut over three continuous cropping cycles and during its seedling and pod-maturing growth stages. Cluster analyses indicated that soil bacterial assemblages obtained from the same peanut cropping cycle were similar, regardless of growth period. The diversity of bacterial sequences identified in each growth stage library of the three peanut cropping cycles was high and these sequences were affiliated with 21 bacterial groups. Eight phyla: Acidobacteria, Actinobacteria, Bacteroidetes, Chloroflexi, Gemmatimonadetes, Planctomycetes, Proteobacteria and Verrucomicrobia were dominant. The related bacterial phylotypes dynamic changed during continuous cropping progress of peanut. This study demonstrated that the bacterial populations especially the beneficial populations were positively selected. The simplification of the beneficial microbial communities such as the phylotypes of Alteromonadales, Burkholderiales, Flavobacteriales, Pseudomonadales, Rhizobiales and Rhodospirillales could be important factors contributing to the decline in peanut yield under continuous cropping. The microbial phylotypes that did not successively changed with continuous cropping, such as populations related to Rhizobiales and Rhodospirillales, could potentially resist stress due to continuous cropping and deserve attention. In addition, some phylotypes, such as Acidobacteriales, Chromatiales and Gemmatimonadales, showed a contrary tendency, their abundance or diversity increased with continuous peanut cropping progress. Some bacterial phylotypes including Acidobacteriales

  7. The impact of roots on soil organic carbon dynamics in annual and perennial agricultural systems

    NASA Astrophysics Data System (ADS)

    Beniston, J.; Dupont, T.; Glover, J.; Lal, R.

    2012-12-01

    Identifying and developing agricultural systems capable of transferring large quantities of carbon (C) to the soil and sustaining ecosystem processes and services is a priority for ecological researchers and land managers. Temperate grasslands have extensive root systems and transfer large quantities of C to the soil organic C (SOC) pool, which has lead to widespread interest in utilizing perennial grasses as both bioenergy crops and as a model for perennial grains. This study examined five sites in north central Kansas (U.S.A.) that contain the unique land use pairing of tall grass prairie meadows (PM) that have been harvested annually for hay for the past 75 years and annual grain (wheat) production fields (AG) that have been cultivated for a similar length of time, all on deep alluvial soils. Specific research objectives included: 1) To quantify below-ground biomass pools and root C contributions in the two systems; 2) To analyze and compare SOC pools and SOC concentration in primary particle size fractions in the two systems; 3) To utilize natural abundance δ13C signatures to determine the source and turnover of SOC in the soils of the AG sites; and 4) To elucidate the relationship of roots to both SOC pools and nematode food webs. Soil core samples were collected to a depth of 1 m in May and June 2008. Soil samples were analyzed for SOC, microbial biomass C (MBC), nematodes, and a particle size fractionation of SOC in coarse (>250 μm), particulate organic matter (POM) (53-250 μm), silt (2-53 μm), and clay (<2 μm) sized fractions. Root biomass, root length and root C were also analyzed to a depth of 1 m. Natural abundance δ13C values were obtained for all C parameters. Soils under PM had 4 times as much root C as AG soils to 1 m depth in mid May (PM 2.8 Mg ha-1 and AG 0.7 Mg ha-1) and 7 times as much root C to 1 m depth in late June (PM 3.5 Mg ha-1 and AG 0.5 Mg ha-1). The MBC pools were significantly larger in grassland soils to a depth of 60 cm in May

  8. Effect of soil acidity factors on yields and foliar composition of tropical root crops

    SciTech Connect

    Abruna-Rodriguez, F.; Vicente-Chandler, J.I. Rivera, E.; Rodriguez, J.

    1982-09-01

    Tropical root crops, a major source of food for subsistence farmers, varied in their sensitivity to soil acidity factors. Tolerance to soil acidity is an important characteristic of crops for the humid tropics where soils are often very acid and lime-scarce and expensive. Experiments on two Ultisols and an Oxisol showed that three tropical root crops differed markedly in sensitivity to soil acicity factors. Yams (Dioscorea alata L.) were very sensitive to soil acidity with yields on a Ultisol decreasing from 70% of maximum when Al saturation of the effective cation exchange capacity of the soil was 10 to 25% of maximum when Al saturation was 40%. On the other hand, cassava (Manihot esculenta Crantz) was very tolerant to high levels of soil acidity, yielding about 85% of maximum with 60% Al saturation. Taniers (Xanthosoma sp.) were intermediate between yams and cassava in their tolerance to soil acidity yielding about 60% of maximum with 50% Al saturation of the soil. Foliar composition of cassava was not affected by soil acidity levels and that of yams and taniers was also unaffected except for Ca content which decreased with decreasing soil pH and increasing Al saturation.Response of these tropical root crops to soil acidity components was far more striking on Ultisols than on the Oxisol. For yams, soils should be limed to about pH 5.5 with essentially no exhangeable Al/sup 3 +/ present whereas high yields of taniers can be obtained at about pH 4.8 with 20% exchangeable Al/sup 3 +/ and of cassava at pH as low as 4.5 with 60% exchangeable Al/sup 3 +/.

  9. Soil quality, crop productivity and soil organic matter (SOM) priming in biochar and wood ash amended soils

    NASA Astrophysics Data System (ADS)

    Reed, Eleanor Swain; Chadwick, David; Hill, Paul; Jones, Davey

    2016-04-01

    The application of energy production by-products as soil amendments to agricultural land is rapidly growing in popularity, however the increasing body of literature on primarily biochar but also wood ash have yielded contrary evidence of the range of these soil amendments function sensitivity in soil. This study aims to assess the efficacy of two by-products; biochar and wood ash to provide nutrients to grassland as well as the potential to improve overall soil quality. The study of soil amendments at field scale are scarce, and the agronomic benefits of biochar and wood ash in temperate soils remain unclear. We used replicated field plots with three soil treatments (biochar, wood ash and control) to measure the soil and crop properties over twelve months, including PLFA analysis to quantify the total soil microbial biomass and community structure. After a soil residency of one year, there were no significant differences in soil EC, total N, dissolved organic N (DON), dissolved organic C (DOC), NO3-N and NH4-N concentrations, between biochar amended, wood ash amended and un-amended soil. In contrast, the application of biochar had a significant effect on soil moisture, pH, PO4-P concentrations, soil organic carbon (SOC) and total organic carbon (TOC), whilst the wood ash amendment resulted in an increase in soil pH only. There were no significant treatment effects on the growth performance or nutrient uptake of the grass. In a parallel laboratory incubation study, the effects of biochar and wood ash on soil C priming was explored, in which soil with 14C-labelled native SOC was amended with either biochar or wood ash at the same rate as the field trial. The rates of 14CO2 (primed C) production was measured with a liquid scintillation counter over a 50 day period. The 14CO2 that evolved during decomposition likely originated from conversions in the (microbial) biomass. The results indicated that biochar application did not prime for the loss of native SOC (i.e. there

  10. Microbial mediation of biogeochemical cycles revealed by simulation of global changes with soil transplant and cropping.

    PubMed

    Zhao, Mengxin; Xue, Kai; Wang, Feng; Liu, Shanshan; Bai, Shijie; Sun, Bo; Zhou, Jizhong; Yang, Yunfeng

    2014-10-01

    Despite microbes' key roles in driving biogeochemical cycles, the mechanism of microbe-mediated feedbacks to global changes remains elusive. Recently, soil transplant has been successfully established as a proxy to simulate climate changes, as the current trend of global warming coherently causes range shifts toward higher latitudes. Four years after southward soil transplant over large transects in China, we found that microbial functional diversity was increased, in addition to concurrent changes in microbial biomass, soil nutrient content and functional processes involved in the nitrogen cycle. However, soil transplant effects could be overridden by maize cropping, which was attributed to a negative interaction. Strikingly, abundances of nitrogen and carbon cycle genes were increased by these field experiments simulating global change, coinciding with higher soil nitrification potential and carbon dioxide (CO2) efflux. Further investigation revealed strong correlations between carbon cycle genes and CO2 efflux in bare soil but not cropped soil, and between nitrogen cycle genes and nitrification. These findings suggest that changes of soil carbon and nitrogen cycles by soil transplant and cropping were predictable by measuring microbial functional potentials, contributing to a better mechanistic understanding of these soil functional processes and suggesting a potential to incorporate microbial communities in greenhouse gas emission modeling.

  11. Microbial mediation of biogeochemical cycles revealed by simulation of global changes with soil transplant and cropping

    PubMed Central

    Zhao, Mengxin; Xue, Kai; Wang, Feng; Liu, Shanshan; Bai, Shijie; Sun, Bo; Zhou, Jizhong; Yang, Yunfeng

    2014-01-01

    Despite microbes' key roles in driving biogeochemical cycles, the mechanism of microbe-mediated feedbacks to global changes remains elusive. Recently, soil transplant has been successfully established as a proxy to simulate climate changes, as the current trend of global warming coherently causes range shifts toward higher latitudes. Four years after southward soil transplant over large transects in China, we found that microbial functional diversity was increased, in addition to concurrent changes in microbial biomass, soil nutrient content and functional processes involved in the nitrogen cycle. However, soil transplant effects could be overridden by maize cropping, which was attributed to a negative interaction. Strikingly, abundances of nitrogen and carbon cycle genes were increased by these field experiments simulating global change, coinciding with higher soil nitrification potential and carbon dioxide (CO2) efflux. Further investigation revealed strong correlations between carbon cycle genes and CO2 efflux in bare soil but not cropped soil, and between nitrogen cycle genes and nitrification. These findings suggest that changes of soil carbon and nitrogen cycles by soil transplant and cropping were predictable by measuring microbial functional potentials, contributing to a better mechanistic understanding of these soil functional processes and suggesting a potential to incorporate microbial communities in greenhouse gas emission modeling. PMID:24694714

  12. Identification of "ever-cropped" land (1984-2010) using Landsat annual maximum NDVI image composites: Southwestern Kansas case study.

    PubMed

    Maxwell, Susan K; Sylvester, Kenneth M

    2012-06-01

    A time series of 230 intra- and inter-annual Landsat Thematic Mapper images was used to identify land that was ever cropped during the years 1984 through 2010 for a five county region in southwestern Kansas. Annual maximum Normalized Difference Vegetation Index (NDVI) image composites (NDVI(ann-max)) were used to evaluate the inter-annual dynamics of cropped and non-cropped land. Three feature images were derived from the 27-year NDVI(ann-max) image time series and used in the classification: 1) maximum NDVI value that occurred over the entire 27 year time span (NDVI(max)), 2) standard deviation of the annual maximum NDVI values for all years (NDVI(sd)), and 3) standard deviation of the annual maximum NDVI values for years 1984-1986 (NDVI(sd84-86)) to improve Conservation Reserve Program land discrimination.Results of the classification were compared to three reference data sets: County-level USDA Census records (1982-2007) and two digital land cover maps (Kansas 2005 and USGS Trends Program maps (1986-2000)). Area of ever-cropped land for the five counties was on average 11.8 % higher than the area estimated from Census records. Overall agreement between the ever-cropped land map and the 2005 Kansas map was 91.9% and 97.2% for the Trends maps. Converting the intra-annual Landsat data set to a single annual maximum NDVI image composite considerably reduced the data set size, eliminated clouds and cloud-shadow affects, yet maintained information important for discriminating cropped land. Our results suggest that Landsat annual maximum NDVI image composites will be useful for characterizing land use and land cover change for many applications.

  13. Dynamics of plant nutrients, utilization and uptake, and soil microbial community in crops under ambient and elevated carbon dioxide

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In natural settings such as under field conditions, the plant available soil nutrients in conjunction with other environmental factors such as, solar radiation, temperature, precipitation, and atmospheric carbon dioxide (CO2) concentration determine crop adaptation and productivity. Therefore, crop...

  14. Organic farming and cover crops as an alternative to mineral fertilizers to improve soil physical properties

    NASA Astrophysics Data System (ADS)

    Sánchez de Cima, Diego; Luik, Anne; Reintam, Endla

    2015-10-01

    For testing how cover crops and different fertilization managements affect the soil physical properties in a plough based tillage system, a five-year crop rotation experiment (field pea, white potato, common barley undersown with red clover, red clover, and winter wheat) was set. The rotation was managed under four different farming systems: two conventional: with and without mineral fertilizers and two organic, both with winter cover crops (later ploughed and used as green manure) and one where cattle manure was added yearly. The measurements conducted were penetration resistance, soil water content, porosity, water permeability, and organic carbon. Yearly variations were linked to the number of tillage operations, and a cumulative effect of soil organic carbon in the soil as a result of the different fertilization amendments, organic or mineral. All the systems showed similar tendencies along the three years of study and differences were only found between the control and the other systems. Mineral fertilizers enhanced the overall physical soil conditions due to the higher yield in the system. In the organic systems, cover crops and cattle manure did not have a significant effect on soil physical properties in comparison with the conventional ones, which were kept bare during the winter period. The extra organic matter boosted the positive effect of crop rotation, but the higher number of tillage operations in both organic systems counteracted this effect to a greater or lesser extent.

  15. How do crop plants tolerate acid soils? Mechanisms of aluminum tolerance and phosphorous efficiency.

    PubMed

    Kochian, Leon V; Hoekenga, Owen A; Pineros, Miguel A

    2004-01-01

    Acid soils significantly limit crop production worldwide because approximately 50% of the world's potentially arable soils are acidic. Because acid soils are such an important constraint to agriculture, understanding the mechanisms and genes conferring tolerance to acid soil stress has been a focus of intense research interest over the past decade. The primary limitations on acid soils are toxic levels of aluminum (Al) and manganese (Mn), as well as suboptimal levels of phosphorous (P). This review examines our current understanding of the physiological, genetic, and molecular basis for crop Al tolerance, as well as reviews the emerging area of P efficiency, which involves the genetically based ability of some crop genotypes to tolerate P deficiency stress on acid soils. These are interesting times for this field because researchers are on the verge of identifying some of the genes that confer Al tolerance in crop plants; these discoveries will open up new avenues of molecular/physiological inquiry that should greatly advance our understanding of these tolerance mechanisms. Additionally, these breakthroughs will provide new molecular resources for improving crop Al tolerance via both molecular-assisted breeding and biotechnology.

  16. Farmers' Perception of Integrated Soil Fertility and Nutrient Management for Sustainable Crop Production: A Study of Rural Areas in Bangladesh

    ERIC Educational Resources Information Center

    Farouque, Md. Golam; Takeya, Hiroyuki

    2007-01-01

    This study aimed to determine farmers' perception of integrated soil fertility and nutrient management for sustainable crop production. Integrated soil fertility (ISF) and nutrient management (NM) is an advanced approach to maintain soil fertility and to enhance crop productivity. A total number of 120 farmers from eight villages in four districts…

  17. Impact of vetch cover crop on runoff, soil loss, soil chemical properties and yield of chickpea in North Gondar, Ethiopia

    NASA Astrophysics Data System (ADS)

    Demelash, Nigus; Klik, Andreas; Holzmann, Hubert; Ziadat, Feras; Strohmeier, Stefan; Bayu, Wondimu; Zucca, Claudio; Abera, Atikilt

    2016-04-01

    Cover crops improve the sustainability and quality of both natural system and agro ecosystem. In Gumara-Maksegnit watershed which is located in Lake Tana basin, farmers usually use fallow during the rainy season for the preceding chickpea production system. The fallowing period can lead to soil erosion and nutrient losses. A field experiment was conducted during growing seasons 2014 and 2015 to evaluate the effect of cover crops on runoff, soil loss, soil chemical properties and yield of chickpea in North Gondar, Ethiopia. The plot experiment contained four treatments arranged in Randomized Complete Block Design with three replications: 1) Control plot (Farmers' practice: fallowing- without cover crop), 2) Chickpea planted with Di-ammonium phosphate (DAP) fertilizer with 46 k ha-1 P2O5 and 23 k ha-1 nitrogen after harvesting vetch cover crop, 3) Chick pea planted with vetch cover crop incorporated with the soil as green manure without fertilizer, 4) Chick pea planted with vetch cover crop and incorporated with the soil as green manure and with 23 k ha-1 P2O5 and 12.5 k ha-1 nitrogen. Each plot with an area of 36 m² was equipped with a runoff monitoring system. Vetch (Vicia sativa L.) was planted as cover crop at the onset of the rain in June and used as green manure. The results of the experiment showed statistically significant (P < 0.05) differences on the number of pods per plant, above ground biomass and grain yield of chick pea. However, there was no statistically significant difference (P > 0.05) on average plant height, average number of branches and hundred seed weight. Similarly, the results indicated that cover crop has a clear impact on runoff volume and sediment loss. Plots with vetch cover crop reduce the average runoff by 65% and the average soil loss decreased from 15.7 in the bare land plot to 8.6 t ha-1 with plots covered by vetch. In general, this result reveales that the cover crops, especially vetch, can be used to improve chickpea grain yield

  18. [Effects of straw returning on the integrated soil fertility and crop yield in southern China].

    PubMed

    Yang, Fan; Dong, Yan; Xu, Ming-Gang; Bao, Yao-Xian

    2012-11-01

    Based on the data from 94 experiments of straw returning in Anhui, Jiangxi, Hunan, Hubei, Guangxi, Sichuan, and Chongqing, and by using mathematic modeling approach, this paper evaluated the effects of straw returning on the soil fertility and crop yield in southern China. Obvious regional differences were observed in the soil fertility index (SFI) and crop yield response. In study area, the croplands with the SFI of Grade III and Grade IV were predominant, occupying 69.1% and 21.3% of the total, respectively. Averagely, straw returning increased the SFI and crop yield by 6.8% and 4.4%, respectively, as compared with the control (no straw returning). The SFI was significantly linearly correlated with rice yield, and could well reflect the integrated soil fertility in study area. At present, straw returning with decomposing agent added is one of the most important measures to improve the integrated soil fertility in southern China, which should be widely popularized.

  19. Relationship between soil copper content and copper content of selected crop plants in central Chile.

    PubMed

    Badilla-Ohlbaum, R; Ginocchio, R; Rodríguez, P H; Céspedes, A; González, S; Allen, H E; Lagos, G E

    2001-12-01

    A survey of copper levels in agricultural soils of central Chile revealed two soil clusters-one with a mean copper level of 162 mg/kg and one with a mean copper level of 751 mg/kg of soil. Samples of soils from both soil clusters were characterized on the basis of physicochemical characteristics, and copper extractability was compared by saturation and CaCl2 extraction as well as an acid-leaching procedure (TCLP). We also measured the copper content of various tissues of tomato (Lycopersicon esculentum) and onion (Allium cepa) crops growing on these soils. Other than copper levels, soils from the two clusters were quite similar, with slightly greater levels of molybdenum and cadmium in the high-copper soils. Within each cluster, extracted copper levels and total soil copper levels were not correlated. However, the three extraction procedures solubilized significantly more copper from the high-Cu soils. Mineralogical characterization of the soil particles and depth profiles of soil metal levels in a subsample of sites suggested that highly insoluble copper ore and mining wastes might account for the high copper levels. Neither total nor extractable copper levels allowed statistical prediction of the levels of copper in plant tissue. The edible tissues of both crops had the same mean copper content, regardless of the copper soil level. However, copper contents of stems and leaves were significantly higher for plants growing on the high-Cu soils. These results show that in these soils, high copper levels are associated with very insoluble copper species and thus low bioavailability of copper to crop plants.

  20. Soil properties and not inputs control carbon, nitrogen, phosphorus ratios in cropped soils in the long-term

    NASA Astrophysics Data System (ADS)

    Frossard, E.; Buchmann, N.; Bünemann, E. K.; Kiba, D. I.; Lompo, F.; Oberson, A.; Tamburini, F.; Traoré, O. Y. A.

    2015-09-01

    Stoichiometric approaches have been applied to understand the relationship between soil organic matter dynamics and biological nutrient transformations. However, very few studies explicitly considered the effects of agricultural management practices on soil C : N : P ratio. The aim of this study was to assess how different input types and rates would affect the C : N : P molar ratios of bulk soil, organic matter and microbial biomass in cropped soils in the long-term. Thus, we analysed the C, N and P inputs and budgets as well as soil properties in three long-term experiments established on different soil types: the Saria soil fertility trial (Burkina Faso), the Wagga Wagga rotation/stubble management/soil preparation trial (Australia), and the DOK cropping system trial (Switzerland). In each of these trials, there was a large range of C, N and P inputs which had a strong impact on element concentrations in soils. However, although C : N : P ratios of the inputs were highly variable, they had only weak effects on soil C : N : P ratios. At Saria, a positive correlation was found between the N : P ratio of inputs and microbial biomass, while no relation was observed between the nutrient ratios of inputs and soil organic matter. At Wagga Wagga, the C : P ratio of inputs was significantly correlated to total soil C : P, N : P and C : N ratios, but had no impact on the elemental composition of microbial biomass. In the DOK trial, a positive correlation was found between the C budget and the C to organic P ratio in soils, while the nutrient ratios of inputs were not related to those in the microbial biomass. We argue that these responses are due to differences in soil properties among sites. At Saria, the soil is dominated by quartz and some kaolinite, has a coarse texture, a fragile structure and a low nutrient content. Thus, microorganisms feed on inputs (plant residues, manure). In contrast, the soil at Wagga Wagga contains illite and haematite, is richer in clay and

  1. Environmental impacts of different crop rotations in terms of soil compaction.

    PubMed

    Götze, Philipp; Rücknagel, Jan; Jacobs, Anna; Märländer, Bernward; Koch, Heinz-Josef; Christen, Olaf

    2016-10-01

    Avoiding soil compaction caused by agricultural management is a key aim of sustainable land management, and the soil compaction risk should be considered when assessing the environmental impacts of land use systems. Therefore this project compares different crop rotations in terms of soil structure and the soil compaction risk. It is based on a field trial in Germany, in which the crop rotations (i) silage maize (SM) monoculture, (ii) catch crop mustard (Mu)_sugar beet (SB)-winter wheat (WW)-WW, (iii) Mu_SM-WW-WW and (iv) SB-WW-Mu_SM are established since 2010. Based on the cultivation dates, the operation specific soil compaction risks and the soil compaction risk of the entire crop rotations are modelled at two soil depths (20 and 35 cm). To this end, based on assumptions of the equipment currently used in practice by a model farm, two scenarios are modelled (100 and 50% hopper load for SB and WW harvest). In addition, after one complete rotation, in 2013 and in 2014, the physical soil parameters saturated hydraulic conductivity (kS) and air capacity (AC) were determined at soil depths 2-8, 12-18, 22-28 and 32-38 cm in order to quantify the soil structure. At both soil depths, the modelled soil compaction risks for the crop rotations including SB (Mu_SB-WW-WW, SB-WW-Mu_SM) are higher (20 cm: medium to very high risks; 35 cm: no to medium risks) than for those without SB (SM monoculture, Mu_SM-WW-WW; 20 cm: medium risks; 35 cm: no to low risks). This increased soil compaction risk is largely influenced by the SB harvest in years where soil water content is high. Halving the hopper load and adjusting the tyre inflation pressure reduces the soil compaction risk for the crop rotation as a whole. Under these conditions, there are no to low soil compaction risks for all variants in the subsoil (soil depth 35 cm). Soil structure is mainly influenced in the topsoil (2-8 cm) related to the cultivation of Mu as a catch crop and WW as a preceding crop. Concerning k

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

    NASA Astrophysics Data System (ADS)

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

    2012-04-01

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

  3. The Importance of Soil Protein Fate to PIP Crop Registration

    EPA Science Inventory

    Plant Incorporated Protectant (PIP) crops are registered under the authority of the Federal Insecticide Fungicide and Rodenticide Act (FIFRA) and as part of this registration certain environmental fate information is required to properly judge the environmental compatibility of n...

  4. Soil health benefits using cover crops across the Southeast

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soils in the southeastern U.S. are very low in organic matter, which can be attributed to high temperatures, humidity, and rainfall that oxidizes organic residues very quickly. Conventional tillage exacerbates this condition and generally contributes to poor soil health. As a result, soils in the r...

  5. Capacity of biochar application to maintain energy crop productivity: soil chemistry, sorghum growth, and runoff water quality effects.

    PubMed

    Schnell, Ronnie W; Vietor, Donald M; Provin, Tony L; Munster, Clyde L; Capareda, Sergio

    2012-01-01

    Pyrolysis of crop biomass generates a by-product, biochar, which can be recycled to sustain nutrient and organic C concentrations in biomass production fields. We evaluated effects of biochar rate and application method on soil properties, nutrient balance, biomass production, and water quality. Three replications of eight sorghum [ (L.) Moench] treatments were installed in box lysimeters under greenhouse conditions. Treatments comprised increasing rates (0, 1.5, and 3.0 Mg ha) of topdressed or incorporated biochar supplemented with N fertilizer or N, P, and K fertilizer. Simulated rain was applied at 21 and 34 d after planting, and mass runoff loss of N, P, and K was measured. A mass balance of total N, P, and K was performed after 45 d. Returning 3.0 Mg ha of biochar did not affect sorghum biomass, soil total, or Mehlich-3-extractable nutrients compared to control soil. Yet, biochar contributed to increased concentration of dissolved reactive phosphorus (DRP) and mass loss of total phosphorus (TP) in simulated runoff, especially if topdressed. It was estimated that up to 20% of TP in topdressed biochar was lost in surface runoff after two rain events. Poor recovery of nutrients during pyrolysis and excessive runoff loss of nutrients for topdressed biochar, especially K, resulted in negative nutrient balances. Efforts to conserve nutrients during pyrolysis and incorporation of biochar at rates derived from annual biomass yields will be necessary for biochar use in sustainable energy crop production.

  6. Effect of Tillage Practices on Soil Properties and Crop Productivity in Wheat-Mungbean-Rice Cropping System under Subtropical Climatic Conditions

    PubMed Central

    Islam, Md. Monirul; Hasanuzzaman, Mirza

    2014-01-01

    This study was conducted to know cropping cycles required to improve OM status in soil and to investigate the effects of medium-term tillage practices on soil properties and crop yields in Grey Terrace soil of Bangladesh under wheat-mungbean-T. aman cropping system. Four different tillage practices, namely, zero tillage (ZT), minimum tillage (MT), conventional tillage (CT), and deep tillage (DT), were studied in a randomized complete block (RCB) design with four replications. Tillage practices showed positive effects on soil properties and crop yields. After four cropping cycles, the highest OM accumulation, the maximum root mass density (0–15 cm soil depth), and the improved physical and chemical properties were recorded in the conservational tillage practices. Bulk and particle densities were decreased due to tillage practices, having the highest reduction of these properties and the highest increase of porosity and field capacity in zero tillage. The highest total N, P, K, and S in their available forms were recorded in zero tillage. All tillage practices showed similar yield after four years of cropping cycles. Therefore, we conclude that zero tillage with 20% residue retention was found to be suitable for soil health and achieving optimum yield under the cropping system in Grey Terrace soil (Aeric Albaquept). PMID:25197702

  7. Copper and lead levels in crops and soils of the Holland Marsh Area-Ontario

    SciTech Connect

    Czuba, M.; Hutchinson, T.C.

    1980-01-01

    A study was made of the occurrence, distribution, and concentrations of the heavy metals copper (Cu) and lead (Pb) in the soils and crops of the important horticultural area north of Toronto known as the Holland Marsh. The soils are deep organic mucks (> 85% organic matter), derived by the drainage of black marshland soils, which has been carried out over the past 40 years. A comparison is made between the Pb and Cu concentrations in undrained, uncultivated areas of the marsh and in the intensively used horticultural area. Analyses show a marked accumulation of Cu in surface layers of cultivated soils, with a mean surface concentration of 130 ppM, declining to 20 ppM at a 32-cm depth. Undrained (virgin) soils of the same marshes had < 20 ppM at all depths. Lead concentrations also declined through the profile, from concentrations of 22 to 10 ppM. In comparison, undrained areas had elevated Pb levels. Cultivation appeared to have increased Cu, but lowered Pb in the marsh. Copper and lead levels found in the crops were generally higher in the young spring vegetables than in the mature fall ones. Leafy crops, especially lettuce (Lactuca L.) and celery (Apium graveolens), accumulated higher Pb levels in their foliage compared with levels in root crops. Cultivation procedures, including past pesticide applications and fertilizer additions, appeared to be principal sources of Cu. Mobility from the soil and into the plant for these elements in the marsh muck soils is discussed.

  8. Effects of long-term continuous cropping on soil nematode community and soil condition associated with replant problem in strawberry habitat

    PubMed Central

    Li, Xingyue; Lewis, Edwin E.; Liu, Qizhi; Li, Heqin; Bai, Chunqi; Wang, Yuzhu

    2016-01-01

    Continuous cropping changes soil physiochemical parameters, enzymes and microorganism communities, causing “replant problem” in strawberry cultivation. We hypothesized that soil nematode community would reflect the changes in soil conditions caused by long-term continuous cropping, in ways that are consistent and predictable. To test this hypothesis, we studied the soil nematode communities and several soil parameters, including the concentration of soil phenolic acids, organic matter and nitrogen levels, in strawberry greenhouse under continuous-cropping for five different durations. Soil pH significantly decreased, and four phenolic acids, i.e., p-hydroxybenzoic acid, ferulic acid, cinnamic acid and p-coumaric acid, accumulated with time under continuous cropping. The four phenolic acids were highly toxic to Acrobeloides spp., the eudominant genus in non-continuous cropping, causing it to reduce to a resident genus after seven-years of continuous cropping. Decreased nematode diversity indicated loss of ecosystem stability and sustainability because of continuous-cropping practice. Moreover, the dominant decomposition pathway was altered from bacterial to fungal under continuous cropping. Our results suggest that along with the continuous-cropping time in strawberry habitat, the soil food web is disturbed, and the available plant nutrition as well as the general health of the soil deteriorates; these changes can be indicated by soil nematode community. PMID:27506379

  9. Effects of long-term continuous cropping on soil nematode community and soil condition associated with replant problem in strawberry habitat

    NASA Astrophysics Data System (ADS)

    Li, Xingyue; Lewis, Edwin E.; Liu, Qizhi; Li, Heqin; Bai, Chunqi; Wang, Yuzhu

    2016-08-01

    Continuous cropping changes soil physiochemical parameters, enzymes and microorganism communities, causing “replant problem” in strawberry cultivation. We hypothesized that soil nematode community would reflect the changes in soil conditions caused by long-term continuous cropping, in ways that are consistent and predictable. To test this hypothesis, we studied the soil nematode communities and several soil parameters, including the concentration of soil phenolic acids, organic matter and nitrogen levels, in strawberry greenhouse under continuous-cropping for five different durations. Soil pH significantly decreased, and four phenolic acids, i.e., p-hydroxybenzoic acid, ferulic acid, cinnamic acid and p-coumaric acid, accumulated with time under continuous cropping. The four phenolic acids were highly toxic to Acrobeloides spp., the eudominant genus in non-continuous cropping, causing it to reduce to a resident genus after seven-years of continuous cropping. Decreased nematode diversity indicated loss of ecosystem stability and sustainability because of continuous-cropping practice. Moreover, the dominant decomposition pathway was altered from bacterial to fungal under continuous cropping. Our results suggest that along with the continuous-cropping time in strawberry habitat, the soil food web is disturbed, and the available plant nutrition as well as the general health of the soil deteriorates; these changes can be indicated by soil nematode community.

  10. Estimated annual agricultural pesticide use by crop group for states of the conterminous United States, 1992-2014

    USGS Publications Warehouse

    Baker, Nancy T.

    2017-01-01

    This dataset provides estimates of annual agricultural use of pesticide compounds by crop group at the state level for states in the conterminous United States, for the time period 1992-2014, compiled from data used to make county-level estimates by means of methods described in Thelin and Stone (2013) and Baker and Stone (2015). The source of this data is the same as the published county-level pesticide use estimates for 1992-2009 (Stone, 2013), estimates for 2008-2012 (Baker and Stone, 2015), and preliminary estimates for 2013 and 2014 respectively, Baker (2015), and Baker (2016). County level by-crop estimates are not published because of the increased uncertainty in estimating the geographic distribution of compounds applied to specific crops. County level estimates were aggregated to state level for high acreage crops such as corn and soybeans, and crop groups for lower acreage crops.

  11. Crop response to localized organic amendment in soils with limiting physical properties

    NASA Astrophysics Data System (ADS)

    Lordan, Joan; Pascual, Miquel; Fonseca, Francisco; Villar, Josep Maria; Montilla, Victor; Papió, Josep; Rufat, Josep

    2013-04-01

    This 2-year study evaluated the use of rice husk as a localized organic amendment in a soil with limiting physical properties. The research was conducted in a commercial peach orchard planted in 2011 using a ridge planting system. Six soil and water management treatments were evaluated in 18 experimental units, which were set up in the field using a randomized complete block design. The treatments were compared both in terms of soil physical properties and crop response. Soil amendment with rice husk was the most effective technique. It improved soil conditions (soil infiltration and soil porosity), providing a better soil environment for root activity and thereby resulted in better crop performance. Concerning growth parameters, the amended treatment presented the highest overall values without negatively affecting crop water status. These techniques were suitable for mitigating the effects of soils with limiting physical conditions. Localized applications of amendments, as proposed in this work, imply an important reduction in application rates. It is important to consider an efficient use of by-products since there is a growing interest in industrial and agronomical exploitations.

  12. Aggregating available soil water holding capacity data for crop yield models

    NASA Technical Reports Server (NTRS)

    Seubert, C. E.; Daughtry, C. S. T.; Holt, D. A.; Baumgardner, M. F.

    1984-01-01

    The total amount of water available to plants that is held against gravity in a soil is usually estimated as the amount present at -0.03 MPa average water potential minus the amount present at -1.5 MPa water potential. This value, designated available water-holding capacity (AWHC), is a very important soil characteristic that is strongly and positively correlated to the inherent productivity of soils. In various applications, including assessing soil moisture status over large areas, it is necessary to group soil types or series as to their productivity. Current methods to classify AWHC of soils consider only total capacity of soil profiles and thus may group together soils which differ greatly in AWHC as a function of depth in the profile. A general approach for evaluating quantitatively the multidimensional nature of AWHC in soils is described. Data for 902 soil profiles, representing 184 soil series, in Indiana were obtained from the Soil Characterization Laboratory at Purdue University. The AWHC for each of ten 150-mm layers in each soil was established, based on soil texture and parent material. A multivariate clustering procedure was used to classify each soil profile into one of 4, 8, or 12 classes based upon ten-dimensional AWHC values. The optimum number of classes depends on the range of AWHC in the population of oil profiles analyzed and on the sensitivity of a crop to differences in distribution of water within the soil profile.

  13. Effect of plastic mulching on mycotoxin occurrence and mycobiome abundance in soil samples from asparagus crops.

    PubMed

    Muñoz, K; Schmidt-Heydt, M; Stoll, D; Diehl, D; Ziegler, J; Geisen, R; Schaumann, G E

    2015-11-01

    Plastic mulching (PM) is widely used in modern agriculture because of its advantageous effects on soil temperature and water conservation, factors which strongly influence the microbiology of the soil. The aim of this study was to assess the effect of PM on mycotoxin occurrence in relation with mycobiome abundance/diversity and soil physicochemical properties. Soil samples were collected from green (GA) and white asparagus (WA) crops, the last under PM. Both crops were cultivated in a ridge-furrow-ridge system without irrigation. Samples were analyzed for mycotoxin occurrence via liquid chromatography coupled to high-resolution mass spectrometry (LC-HRMS). Total colony-forming unit was indicative of mycobiome abundance, and analysis of mycobiome diversity was performed by internal transcribed spacer (ITS) sequencing. PM avoided the drop of soil temperature in winter and allowed higher soil temperature in early spring compared to non-covered soil. Moreover, the use of PM provided controlled conditions for water content in soil. This was enough to generate a dissimilar mycotoxin occurrence and mycobiome diversity/abundance in covered and non-covered soil. Mycotoxin soil contamination was confirmed for deoxynivalenol (DON), range LOD to 32.1 ng/g (LOD = 1.1 ng/g). The DON values were higher under PM (average 16.9 ± 10.1 ng/g) than in non-covered soil (9.1 ± 7.9 ng/g); however, this difference was not statically significant (p = 0.09). Mycobiome analysis showed a fungal compartment up to fivefold higher in soil under PM compared to GA. The diversity of the mycobiome varied between crops and also along the soil column, with an important dominance of Fusarium species at the root zone in covered soils.

  14. Accelerated soil mineralization, nitrification, and revegetation of abandoned fields due to the removal of crop-soil phytotoxicity.

    PubMed

    Lodhi, M A

    1981-07-01

    In an abandoned corn field, clear-cutting of crop vegetation increased the productivity, species richness, and nonannuals in the following years after abandonment, as compared to the control plots from which crop vegetation was not removed. The increase in plant growth was apparently due to the elimination of allelopathic chemicals from the soil, which normally are released from the standing crop. Removal of vegetation also increased the soil mineralization of Ca(2+), Mg(2+), K(+), NH4 (+) and NO3 (-)-N. This situation encouraged species having higher mineral requirements to rapidly invade the fields in the successive years. Clear-cutting also increased the nitrification process by removing the inhibitors of nitrification. The number ofNitrosomonas was always significantly higher in the harvested plots as compared to unharvested plots. Phenolic phytotoxins were isolated from the crop residue and soil. Further, these phytotoxins were significantly higher in the unharvested crops as compared to clear-cut plots, in most samples. Whatever the direct or indirect additional explanation for increased biomass, nonannuals and richness in successive years, it is clear that the removal of standing crop has a definite influence.

  15. The effect of native and introduced biofuel crops on the composition of soil biota communities

    NASA Astrophysics Data System (ADS)

    Heděnec, Petr; Ustak, Sergej; Novotný, David; Frouz, Jan

    2015-04-01

    Biofuel crops are an accepted alternative to fossil fuels, but little is known about the ecological impact of their production. The aim of this contribution is to study the effect of native (Salix viminalis and Phalaris arundinacea) and introduced (Helianthus tuberosus, Reynoutria sachalinensis and Silphium perfoliatum) biofuel crop plantations on the soil biota in comparison with cultural meadow vegetation used as control. The study was performed as part of a split plot field experiment of the Crop Research Institute in the city of Chomutov (Czech Republic). The composition of the soil meso- and macrofauna community, composition of the cultivable fraction of the soil fungal community, cellulose decomposition (using litter bags), microbial biomass, basal soil respiration and PLFA composition (incl. F/B ratio) were studied in each site. The C:N ratio and content of polyphenols differed among plant species, but these results could not be considered significant between introduced and native plant species. Abundance of the soil meso- and macrofauna was higher in field sites planted with S. viminalis and P. arundinacea than those planted with S. perfoliatum, H. tuberosus and R. sachalinensis. RDA and Monte Carlo Permutation Test showed that the composition of the faunal community differed significantly between various native and introduced plants. Significantly different basal soil respiration was found in sites planted with various energy crops; however, this difference was not significant between native and introduced species. Microbial biomass carbon and cellulose decomposition did not exhibit any statistical differences among the biofuel crops. The largest statistically significant difference we found was in the content of actinobacterial and bacterial (bacteria, G+ bacteria and G- bacteria) PLFA in sites overgrown by P. arundinacea compared to introduced as well as native biofuel crops. In conclusion, certain parameters significantly differ between various native

  16. The effect of native and introduced biofuel crops on the composition of soil biota communities

    NASA Astrophysics Data System (ADS)

    Frouz, Jan; Hedenec, Petr

    2016-04-01

    Biofuel crops are an accepted alternative to fossil fuels, but little is known about the ecological impact of their production. The aim of this contribution is to study the effect of native (Salix viminalis and Phalaris arundinacea) and introduced (Helianthus tuberosus, Reynoutria sachalinensis and Silphium perfoliatum) biofuel crop plantations on the soil biota in comparison with cultural meadow vegetation used as control. The study was performed as part of a split plot field experiment of the Crop Research Institute in the city of Chomutov (Czech Republic). The composition of the soil meso- and macrofauna community, composition of the cultivable fraction of the soil fungal community, cellulose decomposition (using litter bags), microbial biomass, basal soil respiration and PLFA composition (incl. F/B ratio) were studied in each site. The C:N ratio and content of polyphenols differed among plant species, but these results could not be considered significant between introduced and native plant species. Abundance of the soil meso- and macrofauna was higher in field sites planted with S. viminalis and P. arundinacea than those planted with S. perfoliatum, H. tuberosus and R. sachalinensis. RDA and Monte Carlo Permutation Test showed that the composition of the faunal community differed significantly between various native and introduced plants. Significantly different basal soil respiration was found in sites planted with various energy crops; however, this difference was not significant between native and introduced species. Microbial biomass carbon and cellulose decomposition did not exhibit any statistical differences among the biofuel crops. The largest statistically significant difference we found was in the content of actinobacterial and bacterial (bacteria, G+ bacteria and G- bacteria) PLFA in sites overgrown by P. arundinacea compared to introduced as well as native biofuel crops. In conclusion, certain parameters significantly differ between various native

  17. Illinois biomass resources: annual crops and residues; canning and food-processing wastes. Preliminary assessment

    SciTech Connect

    Antonopoulos, A A

    1980-06-01

    Illinois, a major agricultural and food-processing state, produces vast amounts of renewable plant material having potential for energy production. This biomass, in the form of annual crops, crop residues, and food-processing wastes, can be converted to alternative fuels (such as ethanol) and industrial chemicals (such as furfural, ethylene, and xylene). The present study provides a preliminary assessment of these Illinois biomass resources, including (a) an appraisal of the effects of their use on both agriculture and industry; (b) an analysis of biomass conversion systems; and (c) an environmental and economic evaluation of products that could be generated from biomass. It is estimated that, of the 39 x 10/sup 6/ tons of residues generated in 1978 in Illinois from seven main crops, about 85% was collectible. The thermal energy equivalent of this material is 658 x 10/sup 6/ Btu, or 0.66 quad. And by fermenting 10% of the corn grain grown in Illinois, some 323 million gallons of ethanol could have been produced in 1978. Another 3 million gallons of ethanol could have been produced in the same year from wastes generated by the state's food-processing establishments. Clearly, Illinois can strengthen its economy substantially by the development of industries that produce biomass-derived fuels and chemicals. In addition, a thorough evaluation should be made of the potential for using the state's less-exploitable land for the growing of additional biomass.

  18. Uav Multispectral Survey to Map Soil and Crop for Precision Farming Applications

    NASA Astrophysics Data System (ADS)

    Sonaa, Giovanna; Passoni, Daniele; Pinto, Livio; Pagliari, Diana; Masseroni, Daniele; Ortuani, Bianca; Facchi, Arianna

    2016-06-01

    New sensors mounted on UAV and optimal procedures for survey, data acquisition and analysis are continuously developed and tested for applications in precision farming. Procedures to integrate multispectral aerial data about soil and crop and ground-based proximal geophysical data are a recent research topic aimed to delineate homogeneous zones for the management of agricultural inputs (i.e., water, nutrients). Multispectral and multitemporal orthomosaics were produced over a test field (a 100 m x 200 m plot within a maize field), to map vegetation and soil indices, as well as crop heights, with suitable ground resolution. UAV flights were performed in two moments during the crop season, before sowing on bare soil, and just before flowering when maize was nearly at the maximum height. Two cameras, for color (RGB) and false color (NIR-RG) images, were used. The images were processed in Agisoft Photoscan to produce Digital Surface Model (DSM) of bare soil and crop, and multispectral orthophotos. To overcome some difficulties in the automatic searching of matching points for the block adjustment of the crop image, also the scientific software developed by Politecnico of Milan was used to enhance images orientation. Surveys and image processing are described, as well as results about classification of multispectral-multitemporal orthophotos and soil indices.

  19. Opposing effects of different soil organic matter fractions on crop yields.

    PubMed

    Wood, Stephen A; Sokol, Noah; Bell, Colin W; Bradford, Mark A; Naeem, Shahid; Wallenstein, Matthew D; Palm, Cheryl A

    2016-10-01

    Soil organic matter is critical to sustainable agriculture because it provides nutrients to crops as it decomposes and increases nutrient- and water-holding capacity when built up. Fast- and slow-cycling fractions of soil organic matter can have different impacts on crop production because fast-cycling fractions rapidly release nutrients for short-term plant growth and slow-cycling fractions bind nutrients that mineralize slowly and build up water-holding capacity. We explored the controls on these fractions in a tropical agroecosystem and their relationship to crop yields. We performed physical fractionation of soil organic matter from 48 farms and plots in western Kenya. We found that fast-cycling, particulate organic matter was positively related to crop yields, but did not have a strong effect, while slower-cycling, mineral-associated organic matter was negatively related to yields. Our finding that slower-cycling organic matter was negatively related to yield points to a need to revise the view that stabilization of organic matter positively impacts food security. Our results support a new paradigm that different soil organic matter fractions are controlled by different mechanisms, potentially leading to different relationships with management outcomes, like crop yield. Effectively managing soils for sustainable agriculture requires quantifying the effects of specific organic matter fractions on these outcomes.

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

    PubMed

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

    2013-01-01

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

  1. Soil carbon stabilization and turnover at alley-cropping systems, Eastern Germany

    NASA Astrophysics Data System (ADS)

    Medinski, T.; Freese, D.

    2012-04-01

    Alley-cropping system is seen as a viable land-use practice for mitigation of greenhouse gas CO2, energy-wood production and soil carbon sequestration. The extent to which carbon is stored in soil varies between ecosystems, and depends on tree species, soil types and on the extent of physical protection of carbon within soil aggregates. This study investigates soil carbon sequestration at alley-cropping systems presented by alleys of fast growing tree species (black locust and poplar) and maize, in Brandenburg, Eastern Germany. Carbon accumulation and turnover are assessed by measuring carbon fractions differing in decomposition rates. For this purpose soil samples were fractionated into labile and recalcitrant soil-size fractions by wet-sieving: macro (>250 µm), micro (53-250 µm) and clay + silt (<53 µm), followed by determination of organic carbon and nitrogen by gas-chromatography. Soil samples were also analysed for the total C&N content, cold-water extractable OC, and microbial C. Litter decomposition was evaluated by litter bags experiment. Soil CO2 flux was measured by LiCor automated device LI-8100A. No differences for the total and stable (clay+silt, <53 µm) carbon fraction were observed between treatment. While cold water-extractable carbon was significantly higher at maize alley compared to black locust alley. This may indicate faster turnover of organic matter at maize alley due to tillage, which influenced greater incorporation of plant residues into the soil, greater soil respiration and microbial activity.

  2. Intercropping Enhances Productivity and Maintains the Most Soil Fertility Properties Relative to Sole Cropping

    PubMed Central

    Wang, Zhi-Gang; Jin, Xin; Bao, Xing-Guo; Li, Xiao-Fei; Zhao, Jian-Hua; Sun, Jian-Hao; Christie, Peter; Li, Long

    2014-01-01

    Yield and nutrient acquisition advantages are frequently found in intercropping systems. However, there are few published reports on soil fertility in intercropping relative to monocultures. A field experiment was therefore established in 2009 in Gansu province, northwest China. The treatments comprised maize/faba bean, maize/soybean, maize/chickpea and maize/turnip intercropping, and their correspoding monocropping. In 2011 (the 3rd year) and 2012 (the 4th year) the yields and some soil chemical properties and enzyme activities were examined after all crop species were harvested or at later growth stages. Both grain yields and nutrient acquisition were significantly greater in all four intercropping systems than corresponding monocropping over two years. Generally, soil organic matter (OM) did not differ significantly from monocropping but did increase in maize/chickpea in 2012 and maize/turnip in both years. Soil total N (TN) did not differ between intercropping and monocropping in either year with the sole exception of maize/faba bean intercropping receiving 80 kg P ha−1 in 2011. Intercropping significantly reduced soil Olsen-P only in 2012, soil exchangeable K in both years, soil cation exchangeable capacity (CEC) in 2012, and soil pH in 2012. In the majority of cases soil enzyme activities did not differ across all the cropping systems at different P application rates compared to monocrops, with the exception of soil acid phosphatase activity which was higher in maize/legume intercropping than in the corresponding monocrops at 40 kg ha−1 P in 2011. P fertilization can alleviate the decline in soil Olsen-P and in soil CEC to some extent. In summary, intercropping enhanced productivity and maintained the majority of soil fertility properties for at least three to four years, especially at suitable P application rates. The results indicate that maize-based intercropping may be an efficient cropping system for sustainable agriculture with carefully managed

  3. Intercropping enhances productivity and maintains the most soil fertility properties relative to sole cropping.

    PubMed

    Wang, Zhi-Gang; Jin, Xin; Bao, Xing-Guo; Li, Xiao-Fei; Zhao, Jian-Hua; Sun, Jian-Hao; Christie, Peter; Li, Long

    2014-01-01

    Yield and nutrient acquisition advantages are frequently found in intercropping systems. However, there are few published reports on soil fertility in intercropping relative to monocultures. A field experiment was therefore established in 2009 in Gansu province, northwest China. The treatments comprised maize/faba bean, maize/soybean, maize/chickpea and maize/turnip intercropping, and their correspoding monocropping. In 2011 (the 3rd year) and 2012 (the 4th year) the yields and some soil chemical properties and enzyme activities were examined after all crop species were harvested or at later growth stages. Both grain yields and nutrient acquisition were significantly greater in all four intercropping systems than corresponding monocropping over two years. Generally, soil organic matter (OM) did not differ significantly from monocropping but did increase in maize/chickpea in 2012 and maize/turnip in both years. Soil total N (TN) did not differ between intercropping and monocropping in either year with the sole exception of maize/faba bean intercropping receiving 80 kg P ha-1 in 2011. Intercropping significantly reduced soil Olsen-P only in 2012, soil exchangeable K in both years, soil cation exchangeable capacity (CEC) in 2012, and soil pH in 2012. In the majority of cases soil enzyme activities did not differ across all the cropping systems at different P application rates compared to monocrops, with the exception of soil acid phosphatase activity which was higher in maize/legume intercropping than in the corresponding monocrops at 40 kg ha-1 P in 2011. P fertilization can alleviate the decline in soil Olsen-P and in soil CEC to some extent. In summary, intercropping enhanced productivity and maintained the majority of soil fertility properties for at least three to four years, especially at suitable P application rates. The results indicate that maize-based intercropping may be an efficient cropping system for sustainable agriculture with carefully managed

  4. [Effects of fertilization on aquic brown soil potassium budget and crop potassium allocation].

    PubMed

    Jiang, Zishao; Yu, Wantai; Zhang, Lu

    2006-12-01

    Through a consecutive 15 years field trial on the aquic brown soil in Shenyang suburb of Northeast China, this paper studied the soil potassium budget and crop potassium allocation under effects of different fertilization systems. The results indicated that applying nitrogen or nitrogen plus phosphorous without potassium application accelerated the deficit of soil potassium. The potassium concentration in soybean grain and stalk was higher under potassium application than with no potassium supply, while that in maize grain had no significant difference in different fertilization treatments. The reutilization of recycled nutrients in farming system could mitigate the deficit of soil potassium budget, and such reutilization assorted with appropriate amount of potassium fertilization could not only produce high crop yield, but also balance soil potassium budget.

  5. Emissions of N2O from peat soils under different cropping systems

    NASA Astrophysics Data System (ADS)

    Norberg, Lisbet; Berglund, Örjan; Berglund, Kerstin

    2016-04-01

    Drainage of peatlands for agriculture use leads to an increase in nitrogen turnover rate causing emissions of N2O to the atmosphere. Agriculture contributes to a substantial part of the anthropogenic emissions of N2O therefore mitigation options for the farmers are important. Here we present a field study with the aim to investigate if the choice of cropping system can mitigate the emission of N2O from cultivated organic soils. The sites used in the study represent fen peat soils with a range of different soil properties located in different parts of southern Sweden. All sites are on active farms with good drainage. N2O emissions from the soil under two different crops grown on the same field, with the same soil type, drainage intensity and weather conditions, are compared by gas sampling. The crops included are oat, barley, carrot, potato and grassland. Three or four sampling occasions during the growing season in 2010 were carried out with static chambers. The N2O emission is calculated from the linear increase of gas concentration in the chamber headspace during the incubation time of 40 minutes. Parallel to the gas sampling soil temperature and soil moisture are measured and some soil properties determined. The result from the gas sampling and measurements show no significant difference in seasonal average N2O emission between the compared crops at any site. There are significant differences in N2O emissions between the compared crops at some of the single sampling occasions but the result vary and no crop can be pointed out as a mitigation option. The seasonal average N2O emissions varies from 16±17 to 1319±1971 μg N2O/m2/h with peaks up to 3317 μg N2O/m2/h. The N2O emission rate from peat soils are determined by other factors than the type of crops grown on the field. The emission rates vary during the season and especially between sites. Although all sites are fen peat soil the soil properties are different, e.g. carbon content varies between 27-43% and

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

    PubMed

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

    2016-04-01

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

  7. Effects of residual disinfectant on soil and lettuce crop irrigated with chlorinated water.

    PubMed

    Lonigro, A; Montemurro, N; Laera, G

    2017-04-15

    The accidental or continuous release of residual chlorine in water reclaimed for irrigational purposes could compromise the crop yield and increase the load of toxic organo-halogenated compounds, posing additional risks for environment and human health. This study was aimed at assessing the consequences of using chlorinated water for irrigating lettuce crops grown in pots with two different types of soil. The results show that the accumulation of extractable organo-halogenated compounds (EOX) in soil, roots and leaves is directly related to the chlorine concentration in the irrigation water. The accumulation of EOX in sandy soils is not significant, while it reached up to 300% of the control in the silty-clay soil, demonstrating that the phenomenon is linked to the organic matter content in the soil. The accumulation of EOX in the soil appears to play a significant role in subsequent bioaccumulation in cultures irrigated with tap water (long term memory effect). Chloramines also demonstrated to have similar impacts as the free chlorine from hypochlorite. The consistent bioaccumulation of 400-700μgClkg(-1) of EOX in the leaves of crops irrigated with just 0.2mgClL(-1) of residual chlorine, as compared to levels below the detection limit of 75μgClkg(-1) in the control crops, evidences the potential impact on food chain and human health.

  8. Managing soil nitrate with cover crops and buffer strips in Sicilian vineyards

    NASA Astrophysics Data System (ADS)

    Novara, A.; Gristina, L.; Guaitoli, F.; Santoro, A.; Cerdà, A.

    2013-04-01

    When soil nitrate levels are inadequate, plants suffer nitrogen deficiency but when the levels are excessive, nitrates (NO3-N) can pollute surface and subsurface waters. Strategies to reduce the nitrate pollution are necessary to reach a sustainable use of resources such as soil, water and plant. Buffer strips and cover crops can contribute to the management of soil nitrates, but little is known of their effectiveness in semiarid vineyards plantations. The experimental site, a 10 m wide and 80 m long area at the bottom of a vineyard was selected in Sicily. The soil between vine rows and upslope of the buffer strip (seeded with Lolium perenne) and non-buffer strips (control) was managed conventionally and with one of two cover crops (Triticum durum and Vicia sativa cover crop). Soil nitrate was measured monthly and nitrate movement was monitored by application of a 15N tracer to a narrow strip between the bottom of vineyard and the buffer and non-buffer strips. L. perenne biomass yield in the buffer strips and its isotopic nitrogen content were monitored. V. sativa cover crop management contribute with an excess of nitrogen, and the soil management determined the nitrogen content at the buffer areas. A 6 m buffer strip reduce the nitrate by 42% with and by 46% with a 9 m buffer strip.

  9. Effects of three species of Chihuahuan Desert ants on annual plants and soil properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We tested the hypothesis that ant species, which occupy the same nest for a decade or longer, would modify nest soils by increasing soil nutrients and microorganisms resulting in increased biomass, density, cover and species richness of annual plants. We measured soil properties and annual plants on...

  10. Distribution of natural and artificial radioactivity in soils, water and tuber crops.

    PubMed

    Darko, Godfred; Faanu, Augustine; Akoto, Osei; Acheampong, Akwasi; Goode, Eric Jude; Gyamfi, Opoku

    2015-06-01

    Activity concentrations of radionuclides in water, soil and tuber crops of a major food-producing area in Ghana were investigated. The average gross alpha and beta activities were 0.021 and 0.094 Bq/L, respectively, and are below the guidelines for drinking water and therefore not expected to pose any significant health risk. The average annual effective dose due to ingestion of radionuclide in water ranged from 20.08 to 53.45 μSv/year. The average activity concentration of (238)U, (232)Th, (40)K and (137)Cs in the soil from different farmlands in the study area was 23.19, 31.10, 143.78 and 2.88 Bq/kg, respectively, which is lower than world averages. The determined absorbed dose rate for the farmlands ranged from 23.63 to 50.51 nGy/year, which is within worldwide range of 18 to 93 nGy/year. The activity concentration of (238)U, (232)Th, (40)K and (137)Cs in cassava ranges from 0.38 to 6.73, 1.82 to 10.32, 17.65 to 41.01 and 0.38 to 1.02 Bq/kg, respectively. Additionally, the activity concentration of (238)U, (232)Th, (40)K and (137)Cs in yam also ranges from 0.47 to 4.89, 0.93 to 5.03, 14.19 to 35.07 and 0.34 to 0.89 Bq/kg, respectively. The average concentration ratio for (238)U, (232)Th and (40)K in yam was 0.12, 0.11 and 0.17, respectively, and in cassava was 0.11, 0.12 and 0.2, respectively. None of the radioactivity is expected to cause significant health problems to human beings.

  11. [Crop-soil nitrogen cycling and soil organic carbon balance in black soil zone of Jilin Province based on DSSAT model].

    PubMed

    Yang, Jing-min; Dou, Sen; Yang, Jing-yi; Hoogenboom, Gerrit; Jiang, Xu; Zhang, Zhong-qing; Jiang, Hong-wei; Jia, Li-hui

    2011-08-01

    By using the CERES-Maize crop model and Century soil model in Decision Support System of Agrotechnology Transfer (DSSAT) model, this paper studied the effects of crop management parameters, fertilizer N application rate, soil initial N supply, and crop residue application on the maize growth, crop-soil N cycling, and soil organic C and N ecological balance in black soil (Mollisol) zone of Jilin Province, Northeast China. Taking 12,000-15,000 kg x hm(-2) as the target yield of maize, the optimum N application rate was 200-240 kg N x hm(-2). Under this fertilization, the aboveground part N uptake was 250-290 kg N x hm(-2), among which, 120-140 kg N x hm(-2) came from soil, and 130-150 kg N x hm(-2) came from fertilizer. Increasing the N application rate (250-420 kg N x hm(-2)) induced an obvious increase of soil residual N (63-183 kg x hm(-2)); delaying the N topdressing date also induced the increase of the residual N. When the crop residue application exceeded 6000 kg x hm(-2), the soil active organic C and N could maintain the supply/demand balance during maize growth season. To achieve the target maize yield and maintain the ecological balance of soil organic C and N in black soil zone of Jilin Province, the chemical N application rate would be controlled in the range of 200-240 kg N x hm(-2), topdressing N should be at proper date, and the application amount of crop residue would be up to 6000 kg x hm(-2).

  12. Root standing crop and chemistry after six years of soil warming in a temperate forest.

    PubMed

    Zhou, Yumei; Tang, Jianwu; Melillo, Jerry M; Butler, Sarah; Mohan, Jacqueline E

    2011-07-01

    Examining the responses of root standing crop (biomass and necromass) and chemistry to soil warming is crucial for understanding root dynamics and functioning in the face of global climate change. We assessed the standing crop, total nitrogen (N) and carbon (C) compounds in tree roots and soil net N mineralization over the growing season after 6 years of experimental soil warming in a temperate deciduous forest in 2008. Roots were sorted into four different categories: live and dead fine roots (≤1mm in diameter) and live and dead coarse roots (1-4 mm in diameter). Total root standing crop (live plus dead) in the top 10 cm of soil in the warmed area was 42.5% (378.4 vs. 658.5 g m(-2)) lower than in the control area, while live root standing crop in the warmed area was 62% lower than in the control area. Soil net N mineralization over the growing season increased by 79.4% in the warmed relative to the control area. Soil warming did not significantly change the concentrations of C and C compounds (sugar, starch, hemicellulose, cellulose and lignin) in the four root categories. However, total N concentration in the live fine roots in the warmed area was 10.5% (13.7 vs. 12.4 mg g(-1)) higher and C:N ratio was 8.6% (38.5 vs. 42.1) lower than in the control area. The increase in N concentration in the live fine roots could be attributed to the increase in soil N availability due to soil warming. Net N mineralization was negatively correlated with both live and dead fine roots in the mineral soil that is home to the majority of roots, suggesting that soil warming increases N mineralization, decreases fine root biomass and thus decreases C allocation belowground.

  13. Spatial distribution and temporal trends of farmland soil PBDEs: processes and crop rotation effects.

    PubMed

    Jiao, Xingchun; Tang, Qifeng; Chen, Shu; Deng, Yajia; Cao, Hongying; Wang, Guang; Yang, Yongliang

    2016-07-01

    The concentration and temporal trend of PBDEs in farmland soil during a circle of crop rotation period within an e-waste dismantling area of South China were investigated. The averaged current concentration of total PBDEs in the farmland soil was averaged 19.1 ± 20.7 ng/g dry weight, which was much lower than the PBDE level in roadside soil and in topsoil near e-waste dismantling sites. Spatial distribution of total PBDEs concentration in the study area showed higher level at the field near e-waste workshops and lower at the distanced farmland area. Soil organic carbon content was significantly correlated with concentration of BDE209 (r = 0.704, p < 0.01), but not related with the sum concentration of other PBDE compounds (r = 0.097, p > 0.1). During the whole crop rotation circle, the temporal concentration of PBDEs in the farmland soil was highest (25.3 ± 11.4 ng/g dry wt.) in April when early paddy had been transplanted for 1 or 2 weeks. When the crop rotated to autumn peanut in August and the land is turning dry, the PBDEs concentration in farmland soil reached the lowest level which was 8.1 ± 1.2 ng/g dry wt. The temporal trend of PBDEs in farmland soil was not consistent with that of atmospheric PBDEs and soil total organic carbon (TOC) content during the rotation cycle. It was concluded that the dynamics of PBDEs in the farmland soil is influenced by multiple, interacting factors, and not clearly related to neither the atmospheric deposition nor the organic carbon content of the soil, but possibly related to the micro-environmental conditions changed by crop rotation process.

  14. Strip-tilled Cover Cropping for Managing Nematodes, Soil Mesoarthropods, and Weeds in a Bitter Melon Agroecosystem

    PubMed Central

    Wang, Koon-Hui; Sipes, Brent S.; Hooks, Cerruti R.R.

    2010-01-01

    A field trial was conducted to examine whether strip-tilled cover cropping followed by living mulch practice could suppress root-knot nematode (Meloidogyne incognita) and enhance beneficial nematodes and other soil mesofauna, while suppressing weeds throughout two vegetable cropping seasons. Sunn hemp (SH), Crotalaria juncea, and French marigold (MG), Tagetes patula, were grown for three months, strip-tilled, and bitter melon (Momordica charantia) seedlings were transplanted into the tilled strips; the experiment was conducted twice (Season I and II). Strip-tilled cover cropping with SH prolonged M. incognita suppression in Season I but not in Season II where suppression was counteracted with enhanced crop growth. Sunn hemp also consistently enhanced bacterivorous and fungivorous nematode population densities prior to cash crop planting, prolonged enhancement of the Enrichment Index towards the end of both cash crop cycles, and increased numbers of soil mesoarthropods. Strip-tilled cover cropping of SH followed by clipping of the living mulch as surface mulch also reduced broadleaf weed populations up to 3 to 4 weeks after cash crop planting. However, SH failed to reduce soil disturbance as indicated by the Structure Index. Marigold suppressed M. incognita efficiently when planted immediately following a M. incognita-susceptible crop, but did not enhance beneficial soil mesofauna including free-living nematodes and soil mesoarthropods. Strip-tilled cover cropping of MG reduced broadleaf weed populations prior to cash crop planting in Season II, but this weed suppression did not last beyond the initial cash crop cycle. PMID:22736847

  15. Managing Cover Crops, Crop Rotation, and Poultry Manure to Increase Soil Health

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Public interest has been stimulated by increasing awareness that soil is a critically important component of the earth’s biosphere, functioning not only in the production of food and fiber but also in the maintenance of local, regional, and global environmental quality. A healthy soil is also the ba...

  16. Management of Lignite Fly Ash for Improving Soil Fertility and Crop Productivity

    NASA Astrophysics Data System (ADS)

    Ram, Lal C.; Srivastava, Nishant K.; Jha, Sangeet K.; Sinha, Awadhesh K.; Masto, Reginald E.; Selvi, Vetrivel A.

    2007-09-01

    Lignite fly ash (LFA), being alkaline and endowed with excellent pozzolanic properties, a silt loam texture, and plant nutrients, has the potential to improve soil quality and productivity. Long-term field trials with groundnut, maize, and sun hemp were carried out to study the effect of LFA on growth and yield. Before crop I was sown, LFA was applied at various doses with and without press mud (an organic waste from the sugar industry, used as an amendment and source of nutrients). LFA with and without press mud was also applied before crops III and V were cultivated. Chemical fertilizer, along with gypsum, humic acid, and biofertilizer, was applied in all treatments, including the control. With one-time and repeat applications of LFA (with and without press mud), yield increased significantly (7.0-89.0%) in relation to the control crop. The press mud enhanced the yield (3.0-15.0%) with different LFA applications. The highest yield LFA dose was 200 t/ha for one-time and repeat applications, the maximum yield being with crop III (combination treatment). One-time and repeat application of LFA (alone and in combination with press mud) improved soil quality and the nutrient content of the produce. The highest dose of LFA (200 t/ha) with and without press mud showed the best residual effects (eco-friendly increases in the yield of succeeding crops). Some increase in trace- and heavy-metal contents and in the level of γ-emitters in soil and crop produce, but well within permissible limits, was observed. Thus, LFA can be used on a large scale to boost soil fertility and productivity with no adverse effects on the soil or crops, which may solve the problem of bulk disposal of fly ash in an eco-friendly manner.

  17. Soil coverage evolution and wind erosion risk on summer crops under contrasting tillage systems

    NASA Astrophysics Data System (ADS)

    Mendez, Mariano J.; Buschiazzo, Daniel E.

    2015-03-01

    The effectiveness of wind erosion control by soil surface conditions and crop and weed canopy has been well studied in wind tunnel experiments. The aim of this study is to assess the combined effects of these variables under field conditions. Soil surface conditions, crop and weed coverage, plant residue, and non-erodible aggregates (NEA) were measured in the field between the fallow start and the growth period of sunflower (Helianthus annuus) and corn (Zea mays). Both crops were planted on a sandy-loam Entic Haplustoll with conventional-(CT), vertical-(VT) and no-till (NT) tillage systems. Wind erosion was estimated by means of the spreadsheet version the Revised Wind Erosion Equation and the soil coverage was measured each 15 days. Results indicated that wind erosion was mostly negligible in NT, exceeding the tolerable levels (estimated between 300 and 1400 kg ha-1 year-1 by Verheijen et al. (2009)) only in an year with high climatic erosivity. Wind erosion exceeded the tolerable levels in most cases in CT and VT, reaching values of 17,400 kg ha-1. Wind erosion was 2-10 times higher after planting of both crops than during fallows. During the fallows, the soil was mostly well covered with plant residues and NEA in CT and VT and with residues and weeds in NT. High wind erosion amounts occurring 30 days after planting in all tillage systems were produced by the destruction of coarse aggregates and the burying of plant residues during planting operations and rains. Differences in soil protection after planting were given by residues of previous crops and growing weeds. The growth of weeds 2-4 weeks after crop planting contributed to reduce wind erosion without impacting in crops yields. An accurate weeds management in semiarid lands can contribute significantly to control wind erosion. More field studies are needed in order to develop management strategies to reduce wind erosion.

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

    SciTech Connect

    Basta, N.T.; Tabatabai, M.A. )

    1992-02-01

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

  19. Simulation of crop yield variability by improved root-soil-interaction modelling

    NASA Astrophysics Data System (ADS)

    Duan, X.; Gayler, S.; Priesack, E.

    2009-04-01

    Understanding the processes and factors that govern the within-field variability in crop yield has attached great importance due to applications in precision agriculture. Crop response to environment at field scale is a complex dynamic process involving the interactions of soil characteristics, weather conditions and crop management. The numerous static factors combined with temporal variations make it very difficult to identify and manage the variability pattern. Therefore, crop simulation models are considered to be useful tools in analyzing separately the effects of change in soil or weather conditions on the spatial variability, in order to identify the cause of yield variability and to quantify the spatial and temporal variation. However, tests showed that usual crop models such as CERES-Wheat and CERES-Maize were not able to quantify the observed within-field yield variability, while their performance on crop growth simulation under more homogeneous and mainly non-limiting conditions was sufficent to simulate average yields at the field-scale. On a study site in South Germany, within-field variability in crop growth has been documented since years. After detailed analysis and classification of the soil patterns, two site specific factors, the plant-available-water and the O2 deficiency, were considered as the main causes of the crop growth variability in this field. Based on our measurement of root distribution in the soil profile, we hypothesize that in our case the insufficiency of the applied crop models to simulate the yield variability can be due to the oversimplification of the involved root models which fail to be sensitive to different soil conditions. In this study, the root growth model described by Jones et al. (1991) was adapted by using data of root distributions in the field and linking the adapted root model to the CERES crop model. The ability of the new root model to increase the sensitivity of the CERES crop models to different enviromental

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

    NASA Astrophysics Data System (ADS)

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

    2013-02-01

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

  1. Soil organic matter composition affected by potato cropping managements

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organic matter is a small but important soil component. As a heterogeneous mixture of geomolecules and biomolecules, soil organic matter (SOM) can be fractionated into distinct pools with different solubility and lability. Water extractable organic matter (WEOM) fraction is the most labile and mobil...

  2. Soil Modification by Native Shrubs Boosts Crop Productivity in Sudano-Sahelian Agroforestry System

    NASA Astrophysics Data System (ADS)

    Bogie, N. A.; Bayala, R.; Diedhiou, I.; Ghezzehei, T. A.; Dick, R.

    2014-12-01

    A changing climate along with human and animal population pressure can have a devastating effect on crop yields and food security in the Sudano-Sahel. Agricultural solutions to address soil degradation and crop water stress are needed to combat this increasingly difficult situation. Significant differences in crop success have been observed in peanut and millet grown in association with two native evergreen shrubs Piliostigma reticulatum, and Guiera senegalensis at the sites of Nioro du Rip and Keur Matar, respectively.We investigate how farmers can increase crop productivity by capitalizing on the evolutionary adaptation of native shrubs to the harsh Sudano-Sahelian environment as well as the physical mechanisms at work in the system that can lead to more robust yields. Soil moisture and water potential data were collected during a dry season millet irrigation experiment where stress was imposed in the intercropped system. Despite lower soil moisture content, crops grown in association with shrubs have increased biomass production and a faster development cycle. Hydraulic redistribution is thought to exist in this system and we found diurnal fluctuations in water potential within the intercropped system that increased in magnitude of to 0.4 Mpa per day as the soil dried below 1.0 Mpa during the stress treatment. An isotopic tracer study investigating hydraulic redistribution was carried out by injecting labeled water into shrub roots and sampling shrubs and nearby crops for isotopic analysis of plant water. These findings build on work that was completed in 2004 at the site, but point to lower overall magnitude of diurnal soil water potential fluctuations in dry soils. Using even the limited resources that farmers possess, this agroforestry technique can be expanded over wide swaths of the Sahel.

  3. Tillage erosion and its effect on soil properties and crop yield in Denmark.

    PubMed

    Heckrath, G; Djurhuus, J; Quine, T A; Van Oost, K; Govers, G; Zhang, Y

    2005-01-01

    Tillage erosion had been identified as a major process of soil redistribution on sloping arable land. The objectives of our study were to investigate the extent of tillage erosion and its effect on soil quality and productivity under Danish conditions. Soil samples were collected to a 0.45-m depth on a regular grid from a 1.9-ha site and analyzed for 137Cs inventories, as a measure of soil redistribution, soil texture, soil organic carbon (SOC) contents, and phosphorus (P) contents. Grain yield was determined at the same sampling points. Substantial soil redistribution had occurred during the past decades, mainly due to tillage. Average tillage erosion rates of 2.7 kg m(-2) yr(-1) occurred on the shoulderslopes, while deposition amounted to 1.2 kg m(-2) yr(-1) on foot- and toeslopes. The pattern of soil redistribution could not be explained by water erosion. Soil organic carbon and P contents in soil profiles increased from the shoulder- toward the toeslopes. Tillage translocation rates were strongly correlated with SOC contents, A-horizon depth, and P contents. Thus, tillage erosion had led to truncated soils on shoulderslopes and deep, colluvial soils on the foot- and toeslopes, substantially affecting within-field variability of soil properties. We concluded that tillage erosion has important implications for SOC dynamics on hummocky land and increases the risk for nutrient losses by overland flow and leaching. Despite the occurrence of deep soils across the study area, evidence suggested that crop productivity was affected by tillage-induced soil redistribution. However, tillage erosion effects on crop yield were confounded by topography-yield relationships.

  4. VARIABLE RATE APPLICATION OF SOIL HERBICIDES IN ARABLE CROPS: FROM THEORY TO PRACTICE.

    PubMed

    Heijting, S; Kempenaar, C

    2014-01-01

    Soil herbicides are applied around crop emergence and kill germinating weeds in the surface layer of the soil. These herbicides play an important role in the chemical management of weeds in major arable crops. From an environmental point of view there is a clear need for smarter application of these chemicals. This paper presents research done in The Netherlands on Variable Rate Application (VRA) of soil herbicides by taking into account spatial variation of the soil. Herbicides adsorbed to soil parameters such as clay or organic matter are not available for herbicidal activity. Decision Support Rules (DSR) describe the relation between the soil parameter and herbicide dosage needed for effectively controlling weeds. Research methods such as greenhouse trials, models and on farm research to develop DSR are discussed and results are presented. Another important ingredient for VRA of soil herbicides is an accurate soil map of the field. Sampling and subsequent interpolation is costly. Soil scans measuring a proxy that is subsequently translated into soil properties such as clay fraction and soil organic matter content offer a quicker way to achieve such maps but validation is needed. DSR is applied to the soil map to get the variable dosage map. The farmer combines this map with the routing, spray volume and spray boom width in the Farm Management Information System (FMIS), resulting in a task file. This task file can subsequently be read by the board computer resulting in a VRA spray map. Reduction in soil herbicide depends on the DSR, the spatial variation and pattern of the soil, the spatial configuration of the routing and the technical advances of the spray equipment. Recently, within the framework the Programma Precisie Landbouw, first steps were made to test and implement this in practice. Currently, theory and practice of VRA of soil herbicides is developed within the research program IJKakker in close cooperation with pioneering farmers in The Netherlands.

  5. Potential soil quality impact of harvesting crop residues for biofuels

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Humankind is in the midst of one of the greatest technological, environmental and social transitions since the industrial revolution, as we strive to replace fossil energy with renewable biomass resources. This presentation will (1) briefly review increased public interest in harvesting crop residue...

  6. Recognition of crops and soils by spot density measurements of imagery

    NASA Technical Reports Server (NTRS)

    Nelson, G. D.

    1970-01-01

    Computerized techniques and methods were used to conduct preliminary soil and crop identification experiments. The soil identification experiment was conducted by making densitometer measurements on Ektachrome infrared film exposed at 14,000 feet. The density measurements were analyzed by plotting sample probability density functions, two-dimensional scatter plots, and the use of K-class I to determine the complete set of classification results for one, two, three and four features. Due to the presence of nineteen classes, crop identification experiments were more difficult to formulate. Classes of corn, fallow, harvested wheat, roadways, trees and water were classified 75 percent correct.

  7. Effects of crop residue on soil and plant water evaporation in a dryland cotton system

    NASA Astrophysics Data System (ADS)

    Lascano, R. J.; Baumhardt, R. L.

    1996-03-01

    Dryland agricultural cropping systems emphasize sustaining crop yields with limited use of fertilizer while conserving both rain water and the soil. Conservation of these resources may be achieved with management systems that retain residues at the soil surface simultaneously modifying both its energy and water balance. A conservation practice used with cotton grown on erodible soils of the Texas High Plains is to plant cotton into chemically terminated wheat residues. In this study, the partitioning of daily and seasonal evapotranspiration ( E t) into soil and plant water evaporation was compared for a conventional and a terminated-wheat cotton crop using the numerical model ENWATBAL. The model was configured to account for the effects of residue on the radiative fluxes and by introducing an additional resistance to latent and sensible heat fluxes derived from measurements of wind speed and vapor conductance from a soil covered with wheat-stubble. Our results showed that seasonal E t was similar in both systems and that cumulative soil water evaporation was 50% of E t in conventional cotton and 31% of E t in the wheat-stubble cotton. Calculated values of E t were in agreement with measured values. The main benefit of the wheat residues was to suppress soil water evaporation by intercepting irradiance early in the growing season when the crop leaf area index (LAI) was low. In semiarid regions LAI of dryland cotton seldom exceeds 2 and residues can improve water conservation. Measured soil temperatures showed that early in the season residues reduced temperature at 0.1 m depth by as much as 5°C and that differences between systems diminished with depth and over time. Residues increased lint yield per unit of E t while not modifying seasonal E t and reducing cumulative soil water evaporation.

  8. Modelling soil borne fungal pathogens of arable crops under climate change

    NASA Astrophysics Data System (ADS)

    Manici, L. M.; Bregaglio, S.; Fumagalli, D.; Donatelli, M.

    2014-12-01

    Soil-borne fungal plant pathogens, agents of crown and root rot, are seldom considered in studies on climate change and agriculture due both to the complexity of the soil system and to the incomplete knowledge of their response to environmental drivers. A controlled chamber set of experiments was carried out to quantify the response of six soil-borne fungi to temperature, and a species-generic model to simulate their response was developed. The model was linked to a soil temperature model inclusive of components able to simulate soil water content also as resulting from crop water uptake. Pathogen relative growth was simulated over Europe using the IPCC A1B emission scenario derived from the Hadley-CM3 global climate model. Climate scenarios of soil temperature in 2020 and 2030 were compared to the baseline centred in the year 2000. The general trend of the response of soil-borne pathogens shows increasing growth in the coldest areas of Europe; however, a larger rate of increase is shown from 2020 to 2030 compared to that of 2000 to 2020. Projections of pathogens of winter cereals indicate a marked increase of growth rate in the soils of northern European and Baltic states. Fungal pathogens of spring sowing crops show unchanged conditions for their growth in soils of the Mediterranean countries, whereas an increase of suitable conditions was estimated for the areals of central Europe which represent the coldest limit areas where the host crops are currently grown. Differences across fungal species are shown, indicating that crop-specific analyses should be ran.

  9. Soil-Water Storage Predictions for Cultivated Crops on the Záhorská Lowlands

    NASA Astrophysics Data System (ADS)

    Jarabicová, Miroslava; Minarič, Peter

    2016-06-01

    The main objective of this paper is to evaluate the impact of climate change on the soil-water regime of the Záhorská lowlands. The consequences of climate change on soil-water storage were analyzed for two crops: spring barley and maize. We analyzed the consequences of climate change on soil-water storage for two crops: spring barley and maize. The soil-water storage was simulated with the GLOBAL mathematical model. The data entered into the model as upper boundary conditions were established by the SRES A2 and SRES B1 climate scenarios and the KNMI regional climate model for the years from 2071 to 2100 (in the text called the time horizon 2085 which is in the middle this period). For the reference period the data from the years 1961-1990 was used. The results of this paper predict soil-water storage until the end of this century for the crops evaluated, as well as a comparison of the soil-water storage predictions with the course of the soil-water storage during the reference period.

  10. Determination of potential management zones from soil electrical conductivity, yield and crop data.

    PubMed

    Li, Yan; Shi, Zhou; Wu, Ci-fang; Li, Hong-yi; Li, Feng

    2008-01-01

    One approach to apply precision agriculture to optimize crop production and environmental quality is identifying management zones. In this paper, the variables of soil electrical conductivity (EC) data, cotton yield data and normalized difference vegetation index (NDVI) data in an about 15 ha field in a coastal saline land were selected as data resources, and their spatial variabilities were firstly analyzed and spatial distribution maps constructed with geostatistics technique. Then fuzzy c-means clustering algorithm was used to define management zones, fuzzy performance index (FPI) and normalized classification entropy (NCE) were used to determine the optimal cluster numbers. Finally one-way variance analysis was performed on 224 georeferenced soil and yield sampling points to assess how well the defined management zones reflected the soil properties and productivity level. The results reveal that the optimal number of management zones for the present study area was 3 and the defined management zones provided a better description of soil properties and yield variation. Statistical analyses indicate significant differences between the chemical properties of soil samples and crop yield in each management zone, and management zone 3 presented the highest nutrient level and potential crop productivity, whereas management zone 1 the lowest. Based on these findings, we conclude that fuzzy c-means clustering approach can be used to delineate management zones by using the given three variables in the coastal saline soils, and the defined management zones form an objective basis for targeting soil samples for nutrient analysis and development of site-specific application strategies.

  11. Keeping soil in the field - runoff and erosion management in asparagus crops

    NASA Astrophysics Data System (ADS)

    Niziolomski, Joanna; Simmons, Robert; Rickson, Jane; Hann, Mike

    2016-04-01

    Row crop production (including potatoes, onions, carrots, asparagus, bulbs and lettuce) is regarded as one of the most erosive agricultural cropping systems. This is a result of the many practices involved that increase erosion risk including: fine seedbed preparation, a typically short growing season where adequate ground cover protects the soil, permanent bare soil areas between crops, and often intensive harvesting methods that can damage soil structure and result in soil compaction. Sustained exposure of bare soil coupled with onsite compaction on slightly sloping land results in soil and water issues in asparagus production. Asparagus production is a growing British industry covering > 2000 ha and is worth approximately £30 million yr-1. However, no tried and tested erosion control measurements currently exist to manage associated problems. Research has recently been undertaken investigating the effectiveness of erosion control measures suitable for asparagus production systems. These consisted of surface applied wheat straw mulch and shallow soil disturbance (< 350 mm) using several tine configurations: a currently adopted winged tine, a narrow with two shallow leading tines, and a modified para-plough. These treatments were tested individually and in combination (straw mulch with each shallow soil disturbance tine configuration) using triplicated field plots situated on a working asparagus farm in Herefordshire, UK. Testing was conducted between May and November 2013. Rainfall-event based runoff and erosion measurements were taken including; runoff volume, runoff rate and total soil loss. Runoff and soil erosion was observed from all treatments. However, the surface application of straw mulch alone out performed each shallow soil disturbance practice. This suggests that runoff and erosion from asparagus production can be reduced using the simple surface application of straw.

  12. The conductance of a maize crop and the underlying soil to ozone under various environmental conditions

    NASA Astrophysics Data System (ADS)

    van Pul, W. A. J.; Jacobs, A. F. G.

    1994-04-01

    Flux measurements of ozone and water vapour employing the eddy correlation technique were used to determine the surface conductance and canopy conductance to ozone. In the surface conductance to ozone, all surfaces at which ozone is destroyed and the transport process to these surfaces are included. The canopy conductance to ozone represents the ozone uptake of transpiring plant parts. The surface conductance to ozone of the maize crop and the underlying soil was generally larger than the canopy conductance to ozone. This means that beside the uptake by stomata, there was another important ozone sink. Under wet soil surface conditions, the surface conductance and the canopy conductance to ozone coincided. This indicates that the resistance of wet soil and the remaining plant parts (cuticle) to ozone was much larger than the stomatal or soil resistance. On the other hand, under dry soil conditions the conductances differ, largely caused by a variation in the transport process to the soil. The transport of ozone to soil increased with increasing friction velocity ( u *) and decreased with increasing atmospheric stability, leaf area index (LAI) or crop height (h). These effects for midday (unstable) conditions were parameterized with an “in-crop” aerodynamic resistance, r inc in a very straightforward way; r inc=13.9 LAI h/u *+67 (cc.=0.77). If the ozone flux in air pollution models is described with a simple resistance model (Big Leaf model), the extra destruction at the soil should be modelled using an “in-crop” aerodynamic resistance. For these measurements the ozone flux to the soil was 0 65% of the total ozone flux measured above the crop. Under wet soil conditions, this was less than 20%; under dry soil conditions, this was 30 65%.

  13. Using a basin-scale hydrological model to estimate crop transpiration and soil evaporation

    NASA Astrophysics Data System (ADS)

    Kite, G.

    2000-03-01

    Increasing populations and expectations, declining crop yields and the resulting increased competition for water necesitate improvements in irrigation management and productivity. A key factor in defining agricultural productivity is to be able to simulate soil evaporation and crop transpiration. In agribusiness terms, crop transpiration is a useful process while soil and open-water evaporations are wasteful processes. In this study a distributed hydrological model was used to compute daily evaporation and transpiration for a variety of crops and other land covers within the 17,200 km 2 Gediz Basin in western Turkey. The model, SLURP, describes the complete hydrological cycle for each land cover within a series of sub-basins including all dams, reservoirs, regulators and irrigation schemes in the basin. The sub-basins and land covers are defined by analysing a digital elevation model and NOAA AVHRR satellite data. In this study, the model uses the FAO implementation of the Penman-Monteith equation to simulate soil evaporation and crop transpiration. The results of the model runs provide time series of data on streamflow at many points along the river system, abstractions and return flows from crops within the irrigation schemes and areally distributed soil evaporation and crop transpiration across the entire basin on each day of an 11 year period. The results show that evaporation and transpiration vary widely across the basin on any one day and over the irrigation season and can be used to evaluate the effectiveness of the various irrigation strategies used in the basin. The advantages of using such a model as compared to deriving evapotranspiration from satellite data are that the model obtains results for each day of an indefinitely long period, as opposed to occasional snapshots, and can also be used to simulate alternate scenarios.

  14. Variation of Bacterial Community Diversity in Rhizosphere Soil of Sole-Cropped versus Intercropped Wheat Field after Harvest

    PubMed Central

    Yang, Zhenping; Yang, Wenping; Li, Shengcai; Hao, Jiaomin; Su, Zhifeng; Sun, Min; Gao, Zhiqiang; Zhang, Chunlai

    2016-01-01

    As the major crops in north China, spring crops are usually planted from April through May every spring and harvested in fall. Wheat is also a very common crop traditionally planted in fall or spring and harvested in summer year by year. This continuous cropping system exhibited the disadvantages of reducing the fertility of soil through decreasing microbial diversity. Thus, management of microbial diversity in the rhizosphere plays a vital role in sustainable crop production. In this study, ten common spring crops in north China were chosen sole-cropped and four were chosen intercropped with peanut in wheat fields after harvest. Denaturing gradient gel electrophoresis (DGGE) and DNA sequencing of one 16S rDNA fragment were used to analyze the bacterial diversity and species identification. DGGE profiles showed the bacterial community diversity in rhizosphere soil samples varied among various crops under different cropping systems, more diverse under intercropping system than under sole-cropping. Some intercropping-specific bands in DGGE profiles suggested that several bacterial species were stimulated by intercropping systems specifically. Furthermore, the identification of these dominant and functional bacteria by DNA sequencing indicated that intercropping systems are more beneficial to improve soil fertility. Compared to intercropping systems, we also observed changes in microbial community of rhizosphere soil under sole-crops. The rhizosphere bacterial community structure in spring crops showed a strong crop species-specific pattern. More importantly, Empedobacter brevis, a typical plant pathogen, was only found in the carrot rhizosphere, suggesting carrot should be sown prudently. In conclusion, our study demonstrated that crop species and cropping systems had significant effects on bacterial community diversity in the rhizosphere soils. We strongly suggest sorghum, glutinous millet and buckwheat could be taken into account as intercropping crops with peanut

  15. [Effects of soil type and crop genotype on cadmium accumulation in peanut (Arachis hypogaea) kernels].

    PubMed

    Wang, Shan-Shan; Zhang, Hong; Wang, Yan-Hong; Wang, Shi-Cheng; Cui, Jie-Hua; Li, Bo; Yang, Jing-Jing

    2012-08-01

    Taking burozem and fluvo-aquic soil in the main peanut (Arachis hypogaea) production areas of China as test soil types and selecting three widely cultivated peanut genotypes Baisha 1016, Huayu 22, and Zhanyou 27 as test crops, a pot experiment with no Cd addition (control) and added with 1.5 mg x kg(-1) of Cd was conducted to elucidate the effects of soil type and crop genotype on the cadmimum (Cd) accumulation in peanut kernels. In the control, the Cd concentrations in the kernels of the three peanut genotypes growing on the two soil types were lower than the national food safety standard. In treatment Cd addition, the opposite was observed. For the same soil types, the Cd concentrations in the kernels of the three peanut genotypes were significantly higher in treatment Cd addition than in the control. The Cd accumulation in the kernels of the three peanut genotypes was in the order of Zhanyou 27 > Baisha 1016 > Huayu 22, and the Cd concentrations in the kernels of the peanut genotypes growing on the two soil types were higher on burozem than on fluvo-aquic soil. The values of the Cd bioaccumulation factor for the kernels of the three peanut genotypes were all higher than 1.0 in the control but lower than 1.0 in treatment Cd addition, suggesting that the peanut kernels had a stronger ability in accumulating the Cd from soil, and, when the soil Cd concentration increased, this ability decreased.

  16. Mapping Surface Soil Organic Carbon for Crop Fields with Remote Sensing

    NASA Technical Reports Server (NTRS)

    Chen, Feng; Kissel, David E.; West, Larry T.; Rickman, Doug; Luvall, J. C.; Adkins, Wayne

    2004-01-01

    The organic C concentration of surface soil can be used in agricultural fields to vary crop production inputs. Organic C is often highly spatially variable, so that maps of soil organic C can be used to vary crop production inputs using precision farming technology. The objective of this research was to demonstrate the feasibility of mapping soil organic C on three fields, using remotely sensed images of the fields with a bare surface. Enough soil samples covering the range in soil organic C must be taken from each field to develop a satisfactory relationship between soil organic C content and image reflectance values. The number of soil samples analyzed in the three fields varied from 22 to 26. The regression equations differed between fields, but gave highly significant relationships with R2 values of 0.93, 0.95, and 0.89 for the three fields. A comparison of predicted and measured values of soil organic C for an independent set of 2 soil samples taken on one of the fields gave highly satisfactory results, with a comparison equation of % organic C measured + 1.02% organic C predicted, with r2 = 0.87.

  17. Changes of multispectral soil patterns with increasing crop canopy

    NASA Technical Reports Server (NTRS)

    Kristof, S. J.; Baumgardner, M. F.

    1972-01-01

    Multispectral data and automatic data processing were used to map surface soil patterns and to follow the changes in multispectral radiation from a field of maize (Zea mays L.) during a period from seeding to maturity. Panchromatic aerial photography was obtained in early May 1970 and multispectral scanner missions were flown on May 6, June 30, August 11 and September 5, 1970 to obtain energy measurements in 13 wavelength bands. The orange portion of the visible spectrum was used in analyzing the May and June data to cluster relative radiance of the soils into eight different radiance levels. The reflective infrared spectral band was used in analyzing the August and September data to cluster maize into different spectral categories. The computer-produced soil patterns had a striking similarity to the soil pattern of the aerial photograph. These patterns became less distinct as the maize canopy increased.

  18. [Variation of microflora and enzyme activity in continuous cropping cucumber soil in solar greenhouse].

    PubMed

    Ma, Yunhua; Wei, Min; Wang, Xiufeng

    2004-06-01

    Variation of microflora and enzyme activity in solar greenhouse soil continuous cropping for 1, 3, 5, 7, 9 years was studied, in addition to the relationship between soil properities and microflora and enzyme activity. The results showed that number of bacteria, actinomyce as well as total microflora showed a trend with a saddle-shaped curve, while the number of fungi appeared an liner increase. Continuous cropping soil microflora shifted from bacteria type to fungi type significantly, of which Ammoniation bacterium and Fusarium oxysporum were main physiology groups. Path analysis results showed that microelements (Mn, Cu, Fe), organic matter, available N and bulk density are main restricted factors of soil microflora and enzyme activity in solar greenhouse.

  19. Ecosystem-service tradeoffs associated with switching from annual to perennial energy crops in riparian zones of the US Midwest.

    PubMed

    Meehan, Timothy D; Gratton, Claudio; Diehl, Erica; Hunt, Natalie D; Mooney, Daniel F; Ventura, Stephen J; Barham, Bradford L; Jackson, Randall D

    2013-01-01

    Integration of energy crops into agricultural landscapes could promote sustainability if they are placed in ways that foster multiple ecosystem services and mitigate ecosystem disservices from existing crops. We conducted a modeling study to investigate how replacing annual energy crops with perennial energy crops along Wisconsin waterways could affect a variety of provisioning and regulating ecosystem services. We found that a switch from continuous corn production to perennial-grass production decreased annual income provisioning by 75%, although it increased annual energy provisioning by 33%, decreased annual phosphorous loading to surface water by 29%, increased below-ground carbon sequestration by 30%, decreased annual nitrous oxide emissions by 84%, increased an index of pollinator abundance by an average of 11%, and increased an index of biocontrol potential by an average of 6%. We expressed the tradeoffs between income provisioning and other ecosystem services as benefit-cost ratios. Benefit-cost ratios averaged 12.06 GJ of additional net energy, 0.84 kg of avoided phosphorus pollution, 18.97 Mg of sequestered carbon, and 1.99 kg of avoided nitrous oxide emissions for every $1,000 reduction in income. These ratios varied spatially, from 2- to 70-fold depending on the ecosystem service. Benefit-cost ratios for different ecosystem services were generally correlated within watersheds, suggesting the presence of hotspots--watersheds where increases in multiple ecosystem services would come at lower-than-average opportunity costs. When assessing the monetary value of ecosystem services relative to existing conservation programs and environmental markets, the overall value of enhanced services associated with adoption of perennial energy crops was far lower than the opportunity cost. However, when we monitized services using estimates for the social costs of pollution, the value of enhanced services far exceeded the opportunity cost. This disparity between

  20. Ecosystem-Service Tradeoffs Associated with Switching from Annual to Perennial Energy Crops in Riparian Zones of the US Midwest

    PubMed Central

    Meehan, Timothy D.; Gratton, Claudio; Diehl, Erica; Hunt, Natalie D.; Mooney, Daniel F.; Ventura, Stephen J.; Barham, Bradford L.; Jackson, Randall D.

    2013-01-01

    Integration of energy crops into agricultural landscapes could promote sustainability if they are placed in ways that foster multiple ecosystem services and mitigate ecosystem disservices from existing crops. We conducted a modeling study to investigate how replacing annual energy crops with perennial energy crops along Wisconsin waterways could affect a variety of provisioning and regulating ecosystem services. We found that a switch from continuous corn production to perennial-grass production decreased annual income provisioning by 75%, although it increased annual energy provisioning by 33%, decreased annual phosphorous loading to surface water by 29%, increased below-ground carbon sequestration by 30%, decreased annual nitrous oxide emissions by 84%, increased an index of pollinator abundance by an average of 11%, and increased an index of biocontrol potential by an average of 6%. We expressed the tradeoffs between income provisioning and other ecosystem services as benefit-cost ratios. Benefit-cost ratios averaged 12.06 GJ of additional net energy, 0.84 kg of avoided phosphorus pollution, 18.97 Mg of sequestered carbon, and 1.99 kg of avoided nitrous oxide emissions for every $1,000 reduction in income. These ratios varied spatially, from 2- to 70-fold depending on the ecosystem service. Benefit-cost ratios for different ecosystem services were generally correlated within watersheds, suggesting the presence of hotspots – watersheds where increases in multiple ecosystem services would come at lower-than-average opportunity costs. When assessing the monetary value of ecosystem services relative to existing conservation programs and environmental markets, the overall value of enhanced services associated with adoption of perennial energy crops was far lower than the opportunity cost. However, when we monitized services using estimates for the social costs of pollution, the value of enhanced services far exceeded the opportunity cost. This disparity between

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

    NASA Astrophysics Data System (ADS)

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

    2015-04-01

    At the interface between atmosphere and deep sub-soil, the root zone plays a major role in regulating the flow of water between major compartments: groundwater / surface / atmosphere (drainage, runoff, evapotranspiration). This role of soil as regulator/control of water fluxes, but also as a supporting medium to plant growth, is strongly dependent on the hydric properties of the soil. In turn, the plant roots growing in the soil can change its structure; both in the plow layer and in the deeper horizons and, therefore, could change the soil properties, particularly hydric properties. Such root-related alteration of soil properties can be linked to direct effect of roots such as soil perforation during growth, aggregation of soil particles or indirect effects such as the release of exudates by roots that could modify the properties of water or of soil particles. On an another hand, the rhizosphere, the zone around roots influenced by the activity of root and associated microorganisms, could have a high influence on hydric properties, particularly the water retention. To test if crops and plant roots rhizosphere may have a significant effect on water retention, we conducted various experiment from laboratory to field scales. In the lab, we tested different soil and species for rhizospheric effect on soil water retention. Variation in available water content (AWC) between bulk and rhizospheric soil varied from non-significant to a significant increase (to about 16% increase) depending on plant species and soil type. In the field, the alteration of water retention by root systems was tested in different pedological settings for a Maize crop inoculated or not with the bacteria Azospirillum spp., known to alter root structure, growth and morphology. Again, a range of variation in AWC was evidenced, with significant increase (~30%) in some soil types, but more linked to innoculated/non-innoculated plants rather than to a difference between rhizospheric and bulk soil

  2. Plant/soil concentration ratios for paired field and garden crops, with emphasis on iodine and the role of soil adhesion.

    PubMed

    Sheppard, S C; Long, J M; Sanipelli, B

    2010-12-01

    In the effort to predict the risks associated with contaminated soils, considerable reliance is placed on plant/soil concentration ratio (CR) values measured at sites other than the contaminated site. This inevitably results in the need to extrapolate among the many soil and plant types. There are few studies that compare CR among plant types that encompass both field and garden crops. Here, CRs for 40 elements were measured for 25 crops from farm and garden sites chosen so the grain crops were in close proximity to the gardens. Special emphasis was placed on iodine (I) because data for this element are sparse. For many elements, there were consistent trends among CRs for the various crop types, with leafy crops > root crops ≥ fruit crops ≈ seed crops. Exceptions included CR values for As, K, Se and Zn which were highest in the seed crops. The correlation of CRs from one plant type to another was evident only when there was a wide range in soil concentrations. In comparing CRs between crop types, it became apparent that the relationships differed for the rare earth elements (REE), which also had very low CR values. The CRs for root and leafy crops of REE converged to a minimum value. This was attributed to soil adhesion, despite the samples being washed, and the average soil adhesion for root crops was 500 mg soil kg⁻¹ dry plant and for leafy crops was 5 g kg⁻¹. Across elements, the log CR was negatively correlated with log Kd (the soil solid/liquid partition coefficient), as expected. Although, this correlation is expected, measures of correlation coefficients suitable for stochastic risk assessment are not frequently reported. The results suggest that r ≈ -0.7 would be appropriate for risk assessment.

  3. Impact of climate, vegetation, soil and crop management variables on multi-year ISBA-A-gs simulations of evapotranspiration over a Mediterranean crop site

    NASA Astrophysics Data System (ADS)

    Garrigues, S.; Olioso, A.; Carrer, D.; Decharme, B.; Martin, E.; Calvet, J.-C.; Moulin, S.; Marloie, O.

    2015-02-01

    Generic land surface models are generally driven by large-scale forcing datasets to describe the climate, the surface characteristics (soil texture, vegetation dynamic) and the cropland management (irrigation). This paper investigates the errors in these forcing variables and their impacts on the evapotranspiration (ET) simulated from the Interactions between Soil, Biosphere, and Atmosphere (ISBA-A-gs) land surface model over a 12 year Mediterranean crop succession. We evaluate the forcing datasets used in the standard implementation of ISBA over France where the model is driven by the SAFRAN high spatial resolution atmospheric reanalysis, the Leaf Area Index (LAI) cycles derived from the Ecoclimap-II land surface parameter database and the soil texture derived from the French soil database. For climate, we focus on the radiations and rainfall variables and we test additional datasets which includes the ERA-Interim low spatial resolution reanalysis, the Global Precipitation Climatology Centre dataset (GPCC) and the MeteoSat Second Generation (MSG) satellite estimate of downwelling shortwave radiations. The methodology consists in comparing the simulation achieved using large-scale forcing datasets with the simulation achieved using local observations for each forcing variable. The relative impacts of the forcing variables on simulated ET are compared with each other and with the model uncertainties triggered by errors in soil parameters. LAI and the lack of irrigation in the simulation generate the largest mean deviations in ET between the large-scale and the local-scale simulations (equivalent to 24 and 19 months of ET over 12 yr). The climate induces smaller mean deviations equivalent to 7-8 months of ET over 12 yr. The soil texture has the lowest impact (equivalent to 3 months of ET). However, the impact of errors in the forcing variables is smaller than the impact triggered by errors in the soil parameters (equivalent to 27 months of ET). The absence of

  4. Management of lignite fly ash for improving soil fertility and crop productivity

    SciTech Connect

    Ram, L.C.; Srivastava, N.K.; Jha, S.K.; Sinha, A.K.; Masto, R.E.; Selvi, V.A.

    2007-09-15

    Lignite fly ash (LFA), being alkaline and endowed with excellent pozzolanic properties, a silt loam texture, and plant nutrients, has the potential to improve soil quality and productivity. Long-term field trials with groundnut, maize, and sun hemp were carried out to study the effect of LFA on growth and yield. Before crop I was sown, LFA was applied at various doses with and without press mud (an organic waste from the sugar industry, used as an amendment and source of nutrients). LFA with and without press mud was also applied before crops III and V were cultivated. Chemical fertilizer, along with gypsum, humic acid, and bioferfertilizer, was applied in all treatments, including the control. With one-time and repeat applications of LFA (with and without press mud), yield increased significantly (7.0-89.0%) in relation to the control crop. The press mud enhanced the yield (3.0-15.0%) with different LFA applications. One-time and repeat application of LFA (alone and in combination with press mud) improved soil quality and the nutrient content of the produce. The highest dose of LFA (200 t/ha) with and without press mud showed the best residual effects (eco-friendly increases in the yield of succeeding crops). Some increase in trace- and heavy metal contents and in the level of gamma-emitters in soil and crop produce, but well within permissible limits, was observed. Thus, LFA can be used on a large scale to boost soil fertility and productivity with no adverse effects on the soil or crops, which may solve the problem of bulk disposal of fly ash in an eco-friendly manner.

  5. Capability of selected crop plants for shoot mercury accumulation from polluted soils: phytoremediation perspectives.

    PubMed

    Rodriguez, Luis; Rincón, Jesusa; Asencio, Isaac; Rodríguez-Castellanos, Laura

    2007-01-01

    High-biomass crops can be considered as an alternative to hyperaccumulator plants to phytoremediate soils contaminated by heavy metals. In order to assess their practical capability for the absorption and accumulation of Hg in shoots, barley, white lupine, lentil, and chickpea were tested in pot experiments using several growth substrates. In the first experimental series, plants were grown in a mixture of vermiculite and perlite spiked with 8.35 microg g(-1) d.w. of soluble Hg. The mercury concentration of the plants' aerial tissues ranged from 1.51 to 5.13 microg g(-1) d.w. with lentil and lupine showing the highest values. In a second experiment carried out using a Hg-polluted soil (32.16 microg g(-1) d.w.) collected from a historical mining area (Almadén, Spain), the crop plants tested only reached shoot Hg concentration up to 1.13 microg g(-1) d.w. In the third experimental series, the Almadén soil was spiked with 1 microg g(-1) d.w. of soluble Hg; as a result, mercury concentrations in the plant shoots increased approximately 6 times for lupine, 5 times for chickpea, and 3.5 times for barley and lentil, with respect to those obtained with the original soil without Hg added. This marked difference was attributed to the low availability of Hg in the original Almadin soil and its subsequent increase in the Hg-spiked soil. The low mercury accumulation yields obtained for all plants do not make a successful decontamination of the Almadén soils possible byphytoremediation using crop plants. However, since the crops tested can effectively decrease the plant-available Hg level in this soil, their use could, to some extent, reduce the environmental risk of Hg pollution in the area.

  6. Long term tillage, cover crop and fertilization effects on microbial community structure and activity: Implications on soil quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Reduced tillage, cover crops and fertilization are associated with greater microbial biomass and activity that are linked to improvements in soil quality, but their impacts vary widely with climate, soils and cropping systems. This study aimed to characterize the impact of long term (31 years) tilla...

  7. Crop and Soil Science. A Curriculum Guide for Idaho Vocational Agriculture Instructors. Volume 1 and Volume 2.

    ERIC Educational Resources Information Center

    Ledington, Richard L.

    The 24 units that comprise this crop and soil science curriculum guide are not geared to a particular age level and must be adapted to the students for whom they are used. Units 1 through 6 are general units covering topics common to soil science. Units 7 through 24 are units covering topics common to crop production. Each unit includes objectives…

  8. Interactions between allelochemicals and the microbial community affect weed suppression following cover crop residue incorporation into soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study is to understand how soil microorganisms interact with cover crop-derived allelochemicals to suppress weed germination and growth following cover crop residue incorporation. We conducted a time series experiment by crossing sterilized and non-sterilized soil with four dif...

  9. Persistence of Mycobacterium avium subsp. paratuberculosis in soil, crops, and ensiled feed following manure spreading on infected dairy farms

    PubMed Central

    Fecteau, Marie-Eve; Hovingh, Ernest; Whitlock, Robert H.; Sweeney, Raymond W.

    2013-01-01

    The goal of this study was to determine the persistence of Mycobacterium avium subsp. paratuberculosis (MAP) in soil, crops, and ensiled feeds following manure spreading. This bacterium was often found in soil samples, but less frequently in harvested feeds and silage. Spreading of manure on fields used for crop harvest is preferred to spreading on grazing pastures. PMID:24179246

  10. The impact of long-term nitrogen fertilizer applications on soil organic carbon in a dryland cereal cropping system of the Loess Plateau

    NASA Astrophysics Data System (ADS)

    Guo, S.

    2011-12-01

    Concerns over food security and global climate change require an improved understanding of how to achieve optimal crop yields whilst minimizing net greenhouse gas emissions from agriculture. In the semi-arid Loess Plateau region of China, as elsewhere, fertilizer nitrogen (N) inputs are necessary to increase yields and improve local food security. In a dryland annual cropping system, we evaluated the effects of N fertilizers on crop yield, its long term impact on soil organic carbon (SOC) concentrations and stock sizes, and the distribution of carbon (C) within various aggregate-size fractions. A current version (RothC) of the Rothamsted model for the turnover of organic C in soil was used to simulate SOC measurements. Five N application rates [0 (N0), 45 (N45), 90 (N90), 135 (N135), and 180 (N180) kg N ha-1] were applied to plots for 25 years (1984-2009) on a loam soil (Cumulic Haplustoll) at the Changwu State Key Agro-Ecological Experimental Station, Shaanxi, China. Crop yield varied with year, but increased over time in the fertilized plots. Average annual grain yields were 1.15, 2.46, 3.11, 3.49, and 3.55 Mg ha-1 with the increasing N application rates, respectively. Long-term N fertilizer application significantly (P<0.05) increased SOC concentrations and stocks in the 0-20 cm horizon. Using RothC, the calculated annual inputs of plant C (in roots, stubble, root exudates, etc.) to the soil were 0.61, 0.74, 0.78, 0.86, and 0.97 t C ha-1 year-1 in N0, N45, N90, N135 and N180 treatments, respectively. The modeled turnover time of SOC (excluding inert organic C) in the continuous wheat cropping system was 26 years. The SOC accumulation rate was estimated to be 40.0, 48.0, 68.0, and 100.0 kg C ha-1 year-1 for the N45, N90, N135 and N180 treatments over 25 years, respectively. As aboveground biomass was removed, the increases in SOC stocks with higher N application are attributed to increased inputs of root biomass and root exudates. Increasing N application rates

  11. How do soil physical conditions for crop growth vary over time under established contrasting tillage regimes?

    NASA Astrophysics Data System (ADS)

    Hallett, Paul; Stobart, Ron; Valentine, Tracy; George, Timothy; Morris, Nathan; Newton, Adrian; McKenzie, Blair

    2014-05-01

    When plant breeders develop modern cereal varieties for the sustainable intensification of agriculture, insufficient thought is given to the impact of tillage on soil physical conditions for crop production. In earlier work, we demonstrated that barley varieties that perform best in ploughed soil (the approach traditionally used for breeding trials) were not the same as those performing best under shallow non-inversion or zero-tillage. We also found that the Quantitative Trait Loci (QTL) associated with improved phosphorus uptake, and hence useful for marker assisted breeding, were not robust between different tillage regimes. The impact of the soil environment had greater impact than the genetics in GxE interactions. It is obvious that soil tillage should be considered when breeding the next generation of crops. Tillage may also have important impacts on carbon storage, but we found that despite greater soil carbon at shallow depths under non-inversion tillage, the carbon stored throughout the soil profile was not affected by tillage. Studies on soil tillage impacts to crop productivity and soil quality are often performed in one season, on single sites that have had insufficient time to develop. Our current research explores multiple sites, on different soils, with temporal measurements of soil physical conditions under contrasting tillage regimes. We use the oldest established contemporary tillage experiments in the United Kingdom, with all sites sharing ploughed and shallow (7cm) non-inversion tillage treatments. In eastern Scotland (Mid Pilmore), the site also has zero tillage and deep ploughing (40 cm) treatments, and was established 11 years ago. In east England there are two sites, both also having a deep non-inversion tillage treatment, and they were established 6 (New Farm Systems) and 8 (STAR) years ago. We measure a range of crop and soil properties at sowing, one month after sowing and post-harvest, including rapid lab based assays that allow high

  12. Enzyme dynamics in paddy soils of the rice district (NE Italy) under different cropping patterns

    NASA Astrophysics Data System (ADS)

    Bini, Claudio; Nadimi-Goki, Mandana; Kato, Yoichi; Fornasier, Flavio; Wahsha, Mohammad; Spiandorello, Massimo

    2014-05-01

    The recent widespread interest on soil enzymes is due to the need to develop sensitive indicators of soil quality that reflect the effects of land management on soil and assist land managers in promoting long-term sustainability of terrestrial ecosystems. The activities of six important enzymes involved in C, N, P, and S cycling were investigated in a paddy soil from the Veneto region, Italy, in four different rotation systems (rice-rice-rice: R-R-R; soya-rice-rice: S-R-R; fallow-rice: F-R; pea-soya-rice: P-S-R) with three replications in April (after field preparation, field moist condition), June (after seedling, waterlogged soil condition), August (after tillering stage of rice, waterlogged soil condition) and October (after rice harvesting, drained soil condition) over the 2012 growing season. Our results demonstrated that enzyme activities varied with rotation systems and growth stages in paddy soil. Compared with field moist soil, drained soil condition resulted in a significant increase (P < 0.05) of β-glucosidase, arylsulfatase, alkaline and acid phosphatases, leucine aminopeptidase (except of fallow-rice), and chitinase activities in all rotations, while compared with drained soil, early waterlogging (in month of June) significantly decreased (P moist soil> late waterlogged>early waterlogged. There was an inhibitory effect of waterlogging (except P-S-R rotation) for both alkaline and acid phosphatases due to high pH and redox conditions. However, the response of enzymes to waterlogging differed with the chemical species and the cropping pattern. The best rotation system for chitinase, leucine aminopeptidase and β-glucosidase activity (C and N cycles) proved R-R-R, while for arylsulfatase, alkaline and acid phosphatases (P and S cycles) it was the S-R-R. Key Words: enzyme activity, paddy soil, Crop Rotation System, Italy __ Corresponding Author: Mandana Nadimi-Goki, Tel.: +39 3891356251 E-mail address: mandy.nadimi@gmail.com

  13. Legacy Phosphorus Effect and Need to Re-calibrate Soil Test P Methods for Organic Crop Production.

    NASA Astrophysics Data System (ADS)

    Dao, Thanh H.; Schomberg, Harry H.; Cavigelli, Michel A.

    2015-04-01

    Phosphorus (P) is a required nutrient for the normal development and growth of plants and supplemental P is needed in most cultivated soils. Large inputs of cover crop residues and nutrient-rich animal manure are added to supply needed nutrients to promote the optimal production of organic grain crops and forages. The effects of crop rotations and tillage management of the near-surface zone on labile phosphorus (P) forms were studied in soil under conventional and organic crop management systems in the mid-Atlantic region of the U.S. after 18 years due to the increased interest in these alternative systems. Soil nutrient surpluses likely caused by low grain yields resulted in large pools of exchangeable phosphate-P and equally large pools of enzyme-labile organic P (Po) in soils under organic management. In addition, the difference in the P loading rates between the conventional and organic treatments as guided by routine soil test recommendations suggested that overestimating plant P requirements contributed to soil P surpluses because routine soil testing procedures did not account for the presence and size of the soil enzyme-labile Po pool. The effect of large P additions is long-lasting as they continued to contribute to elevated soil total bioactive P concentrations 12 or more years later. Consequently, accurate estimates of crop P requirements, P turnover in soil, and real-time plant and soil sensing systems are critical considerations to optimally manage manure-derived nutrients in organic crop production.

  14. Macronutrients and trace metals in soil and food crops of Isfahan Province, Iran.

    PubMed

    Keshavarzi, Behnam; Moore, Farid; Ansari, Maryam; Rastegari Mehr, Meisam; Kaabi, Helena; Kermani, Maryam

    2015-01-01

    The distribution of 10 macronutrients and trace metals in the arable soils of Isfahan Province, their phytoavailability, and associated health risks were investigated; 134 plant and 114 soil samples (from 114 crop fields) were collected and analyzed at harvesting time. Calculation of the soil pollution index (SPI) revealed that arable soil polluted by metals was more severe in the north and southwest of the study area. The results of cluster analysis indicated that Pb, Zn, and Cu share a similar origin from industries and traffic. The concentrations of macronutrients and trace metals in the sampled crops were found in the order of K > Ca > S > Mg > P and Fe > Mn > Zn > Cu > Pb, respectively, whereas calculation of the bioconcentration factor (BCF) indicated that the accumulation of the investigated elements in crops was generally in the order of S ≈ K > P > Mg > Ca and Zn > Cu > Mn > Pb > Fe, respectively. Thus, various parameters including crop species and the physical, chemical, and biological properties of soil also affected the bioavailability of the elements besides the total element contents in soil. Daily intake (DI) values of elements were lower than the recommended daily intake (RDI) levels in rice grains except for Fe and Mn, but for wheat grains, all elements displayed DI values higher than the RDI. Moreover, based on the hazard index (HI) values, inhabitants are experiencing a significant potential health risk solely due to the consumption of wheat and rice grains (particularly wheat grains). Mn health quotient (HQ) also indicated a high risk of Mn absorption for crop consumer inhabitants.

  15. Phytoextraction of Pb and Cd from a superfund soil: effects of amendments and croppings.

    PubMed

    Bricker, T J; Pichtel, J; Brown, H J; Simmons, M

    2001-01-01

    In a growth chamber, maize (Zea mays) and Indian mustard (Brassica juncea) were grown over two croppings in soil from a Superfund site (PbTotal = 65,200 mg/kg and CdTotal = 52mg/kg). Soil treatments consisted of ethylenediaminetetraacetic acid, sodium citrate and composted sewage sludge, each at two rates (EDTA .05%, EDTA .2%, citrate .05%, citrate .2%, CSS 5% and CSS 10%, respectively). In most cases, the EDTA and citrate treatments were superior in terms of solubilizing soil Pb for root uptake and translocation into above-ground biomass. In the first maize crop, the EDTA .2% treatment resulted in 2,435 and 9,389mg/kg Pb in shoot and root tissues, respectively. The CSS treatments typically resulted in lowest Pb and Cd removal efficiencies. Lead remaining in the soil after two croppings was mainly associated with the carbonate, organic, and residual fractions, which represent the less bioavailable forms. Soil Cd was generally more mobile for plant uptake than soil Pb. The EDTA .2% and citrate treatments were most successful in promoting Cd uptake by both maize and mustard. Although Pb concentrations (mg/kg tissue) were lower for maize than mustard, the former removed more total Pb (0.2 mg per pot, mean over all treatments), compared to mustard (0.03 mg), by virtue of its higher biomass production.

  16. Soil Carbon Changes in Transitional Grain Crop Production Systems in South Dakota

    NASA Astrophysics Data System (ADS)

    Woodard, H. J.

    2004-12-01

    Corn-C (Zea Mays L.), soybean-S (Glycine max L.) and spring wheat-W (Triticum aestivum L.) crops were seeded as a component of either a C-S, S-W, or C-S-W crop rotation on silt-loam textured soils ranging from 3.0-5.0% organic matter. Conservation tillage(chisel plow-field cultivator) was applied to half of the plots. The other plots were direct seeded as a no-till (zero-tillage) treatment. Grain yield and surface crop residues were weighed from each treatment plot. Crop residue (stover and straw) was removed from half of the plots. After four years, soil samples were removed at various increments of depth and soil organic carbon (C) and nitrogen (N) was measured. The ranking of crop residue weights occurred by the order corn>>soybean>wheat. Surface residue accumulation was also greatest with residue treatments that were returned to the plots, those rotations in which maize was a component, and those without tillage. Mean soil organic carbon levels in the 0-7.5cm depth decreased from 3.41% to 3.19% (- 0.22%) with conventional tillage (chisel plow/field cultivator) as compared to a decrease from 3.19% to 3.05% (-0.14%) in plots without tillage over a four year period. Organic carbon in the 0-7.5cm depth decreased from 3.21% to 3.01% (- 0.20%) after residue removed as compared to a decrease from 3.39% to 3.23% (-0.17%) in plots without tillage applied after four years. The soil C:N ratio (0-7.5cm) decreased from 10.63 to 10.37 (-0.26 (unitless)) in the tilled plots over a four-year period. Soil C:N ratio at the 0-7.5cm depth decreased from 10.72 to 10.04 (-0.68) in the no-till plots over a four year period. Differences in the soil C:N ratio comparing residue removed and residue returned were similar (-0.51 vs. -0.43 respectively). These soils are highly buffered for organic carbon changes. Many cropping cycles are required to determine how soil carbon storage is significantly impacted by production systems.

  17. Impact of paper mill wastewater on soil properties and crop yield through lysimeter studies.

    PubMed

    Singh, P K; Ladwani, K; Ladwani, K; Deshbhratar, P B; Ramteke, D S

    2013-01-01

    Paper and pulp industries produce large quantities of wastewater which can have adverse effects on the receiving water systems. In the present study lysimeters were used and filled with different soils replicating natural soil horizons and provided with a leachate collection system. The physico-chemical characteristics of the soil in each lysimeter and the quality of wastewater before leaching were assessed. Treated wastewater was evaluated for crop irrigation, and was categorized according to the irrigation water class 'Increasing Problem to Severe Problem' with respect to salinity and specific ion toxicity. Sandy loam soils showed 96% chemical oxygen demand (COD) removal while clay loam soils removed 99% of COD, and the colour removal in both the cases was found to be 100%. Application of wastewater resulted in an increase of pH value, ranging from 6.2-7.6; the electrical conductivity (ECe) of saturated extracts was found to be 0.6-1.7 dS m(-1), and exchangeable sodium percentage (ESP) ranged from 7.8-11.1% in soils. Similarly, an increase in the organic carbon, available nitrogen, phosphorus and potash content of soils was observed when irrigated with wastewater. Wastewater irrigation showed increased grain and straw yield of jowar, wheat and moong. These results permit successful utilization of pulp and paper mill wastewater for crop production without damaging the soils.

  18. Impact of topography and soil factors on crop suitability in two Mediterranean areas (Egypt and Spain)

    NASA Astrophysics Data System (ADS)

    Abd-Elmabod, S. K.; Jordán, A.; Anaya-Romero, M.; Ali, R. R.; Muñoz-Rojas, M.; Zavala, L. M.; de la Rosa, D.

    2012-04-01

    The aim of this research is to study the influence of topography and soil factors on crop suitability two Mediterranean areas: Sevilla (southern Spain) and El-Fayoum (northern Egypt). The Shuttle Radar Topography Mission (SRTM) images were processed using ENVI 4.7 software to extract elevation data, slope gradient and slope direction. North-south toposequences from both areas were extracted and studied using Arc-GIS 9.3 software. Soil characteristics along these toposequences were extracted from regional soil maps, as well as land surveying and laboratory analyses. The Almagra model (included in the agro-ecological system MicroLEIS DSS) was used to evaluate agricultural soil suitability using soil factors of useful depth, texture, drainage, carbonate content, salinity, sodium saturation, and degree of development of the profile. Changes of soil characteristics through the toposequences are discussed. The results of Almagra model indicate that the crop suitability main limiting factors are soil texture, drainage, soil salinity and sodium saturation percent and topography factors elevation, slope gradient, slope direction.

  19. Cover crops alter phosphorus soil fractions and organic matter accumulation in a Peruvian cacao agroforestry system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In many tropical soils, excessive weathering of primary minerals confounded by intense agricultural production has resulted in the depletion of organic matter and plant available forms of phosphorus (P). Long-term growth of cover crops in tropical agroforestry systems have been shown to influence nu...

  20. Cover crop, soil amendments, and variety effects on organic rice production in Texas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The major challenges in organic rice production include optimization of nutrient utilization, weed management, and variety selection. In this study, we tested the effects of two soil amendment products, two fertilizer rates, and three cover cropping systems (clover, ryegrass, and fallow) on organic ...

  1. Assimilation of active and passive microwave observations for improved estimates of soil moisture and crop growth

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An Ensemble Kalman Filter-based data assimilation framework that links a crop growth model with active and passive (AP) microwave models was developed to improve estimates of soil moisture (SM) and vegetation biomass over a growing season of soybean. Complementarities in AP observations were incorpo...

  2. Long-term effects of compost and cover crops on soil phosphorus in two California agroecosystems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Inefficient P use in agriculture results in soil P accumulation and losses to surrounding ecosystems, highlighting the need to reduce external inputs and use them more efficiently. Composts reduce the need for mineral fertilizers by recycling P from wastes at the regional scale, whereas cover crops ...

  3. Perfluoroalkyl acid distribution in various plant compartments of edible crops grown in biosolids-amended soils

    EPA Science Inventory

    Crop uptake of perfluoroalkyl acids (PFAAs) from biosolids-amended soil has been identified as a potential pathway for PFAA entry into the terrestrial food chain. This study compared the uptake of PFAAs in greenhouse-grown radish (Raphanus sativus), celery (Apium graveolens var.d...

  4. Stagnating crop yields: An overlooked risk for the carbon balance of agricultural soils?

    PubMed

    Wiesmeier, Martin; Hübner, Rico; Kögel-Knabner, Ingrid

    2015-12-01

    The carbon (C) balance of agricultural soils may be largely affected by climate change. Increasing temperatures are discussed to cause a loss of soil organic carbon (SOC) due to enhanced decomposition of soil organic matter, which has a high intrinsic temperature sensitivity. On the other hand, several modeling studies assumed that potential SOC losses would be compensated or even outperformed by an increased C input by crop residues into agricultural soils. This assumption was based on a predicted general increase of net primary productivity (NPP) as a result of the CO2 fertilization effect and prolonged growing seasons. However, it is questionable if the crop C input into agricultural soils can be derived from NPP predictions of vegetation models. The C input in European croplands is largely controlled by the agricultural management and was strongly related to the development of crop yields in the last decades. Thus, a glance at past yield development will probably be more instructive for future estimations of the C input than previous modeling approaches based on NPP predictions. An analysis of European yield statistics indicated that yields of wheat, barley and maize are stagnating in Central and Northern Europe since the 1990s. The stagnation of crop yields can probably be related to a fundamental change of the agricultural management and to climate change effects. It is assumed that the soil C input is concurrently stagnating which would necessarily lead to a decrease of agricultural SOC stocks in the long-term given a constant temperature increase. Remarkably, for almost all European countries that are faced with yield stagnation indications for agricultural SOC decreases were already found. Potentially adverse effects of yield stagnation on the C balance of croplands call for an interdisciplinary investigation of its causes and a comprehensive monitoring of SOC stocks in agricultural soils of Europe.

  5. The influence of cover crops and tillage on actual and potential soil erosion in an olive grove

    NASA Astrophysics Data System (ADS)

    Sastre, Blanca; Bienes, Ramón; García-Díaz, Andrés; Panagopoulos, Thomas; José Marqués, Maria

    2014-05-01

    The study was carried out in an olive grove in central Spain (South of Madrid; Tagus River Basin). In this semi-arid zone, the annual mean temperature is 13.8 ºC and the annual precipitation is 395 mm. Olive groves are planted in an erosion prone area due to steep slopes up to 15%. Soil is classified as Typic Haploxerept with clay loam texture. The land studied was formerly a vineyard, but it was replaced by the studied olive grove in 2004. It covers approximately 3 ha and olive trees are planted every 6 x 7 metres. They were usually managed by tillage to decrease weed competition. This conventional practice results in a wide surface of bare soil prone to erosion processes. In the long term soil degradation may lead to increase the desertification risk in the area. Storms have important consequences in this shallow and vulnerable soil, as more than 90 Mg ha-1 have been measured after one day with 40 mm of rainfall. In order to avoid this situation, cover crops between the olive trees were planted three years ago: sainfoin (Onobrychis viciifolia), barley (Hordeum vulgare), and purple false brome (Brachypodium distachyon), and they were compared with annual spontaneous vegetation after a minimum tillage treatment (ASV). The results regarding erosion control were positive. We observed (Oct. 2012/Sept. 2013) annual soil loss up to 11 Mg ha-1 in ASV, but this figure was reduced in the sown covers, being 8 Mg ha-1 in sainfoin treatment, 3,7 Mg ha-1 in barley treatment, and only 1,5 Mg ha-1 in false brome treatment. Those results are used to predict the risk of erosion in long term. Moreover, soil organic carbon (SOC) increased with treatments, this is significant as it reduces soil erodibility. The increases were found both in topsoil (up to 5 cm) and more in depth, in the root zone (from 5 to 10 cm depth). From higher to lower SOC values we found the false brome (1.05%), barley (0.92%), ASV (0.79%) and sainfoin (0.71%) regarding topsoil. In the root zone (5-10 cm depth

  6. Changes in N-transforming archaea and bacteria in soil during the establishment of bioenergy crops.

    PubMed

    Mao, Yuejian; Yannarell, Anthony C; Mackie, Roderick I

    2011-01-01

    Widespread adaptation of biomass production for bioenergy may influence important biogeochemical functions in the landscape, which are mainly carried out by soil microbes. Here we explore the impact of four potential bioenergy feedstock crops (maize, switchgrass, Miscanthus X giganteus, and mixed tallgrass prairie) on nitrogen cycling microorganisms in the soil by monitoring the changes in the quantity (real-time PCR) and diversity (barcoded pyrosequencing) of key functional genes (nifH, bacterial/archaeal amoA and nosZ) and 16S rRNA genes over two years after bioenergy crop establishment. The quantities of these N-cycling genes were relatively stable in all four crops, except maize (the only fertilized crop), in which the population size of AOB doubled in less than 3 months. The nitrification rate was significantly correlated with the quantity of ammonia-oxidizing archaea (AOA) not bacteria (AOB), indicating that archaea were the major ammonia oxidizers. Deep sequencing revealed high diversity of nifH, archaeal amoA, bacterial amoA, nosZ and 16S rRNA genes, with 229, 309, 330, 331 and 8989 OTUs observed, respectively. Rarefaction analysis revealed the diversity of archaeal amoA in maize markedly decreased in the second year. Ordination analysis of T-RFLP and pyrosequencing results showed that the N-transforming microbial community structures in the soil under these crops gradually differentiated. Thus far, our two-year study has shown that specific N-transforming microbial communities develop in the soil in response to planting different bioenergy crops, and each functional group responded in a different way. Our results also suggest that cultivation of maize with N-fertilization increases the abundance of AOB and denitrifiers, reduces the diversity of AOA, and results in significant changes in the structure of denitrification community.

  7. Soil arsenic availability and the transfer of soil arsenic to crops in suburban areas in Fujian Province, southeast China.

    PubMed

    Huang, Rui-Qing; Gao, Shu-Fang; Wang, Wei-Ling; Staunton, S; Wang, Guo

    2006-09-15

    The bioavailability, soil-to-plant transfer and associated health risks of arsenic in soils collected from paddy rice fields and vegetable fields in suburban areas of some major cities of Fujian Province were investigated. The total soil concentrations of arsenic ranged from 1.29 to 25.28 mg kg(-)(1) with a mean of 6.09 mg kg(-)(1). Available (NaH(2)PO(4)-extractable) arsenic content accounted for 0.7-38.2% of total soil arsenic and was significantly correlated with total soil arsenic content. For the vegetable soils, the available fraction (ratio of available As to total As) of arsenic decreased with decreasing silt (particle size 0.02-0.002 mm) and free iron (DCB extractable) contents and with increasing soil pH and organic matter content. The available fraction of arsenic in the paddy rice soils increased with increasing free iron and organic matter contents and decreasing soil pH and silt content. The correlation of NaH(2)PO(4)-extractable arsenic with the arsenic concentration of the vegetables was much better than that of total As. The transfer factor based on the soil available arsenic (TF(avail)) was chosen to compare the accumulation ability of the various crops. The TF(avail) values of rice grains (air-dried weight basis) ranged between 0.068 and 0.44 and were higher than those of the vegetables, ranging from 0.001 to 0.12. The accumulation ability of the crops decreased in the order of rice>radish>water spinach>celery>onion>taro>leaf mustard>fragrant-flowered garlic>pakchoi>Chinese cabbage>lettuce>garlic>cowpea>cauliflower>bottle gourd>towel gourd>eggplant. Daily consumption of rice and other As-rich vegetables could result in an excessive intake of arsenic, based on the provisional tolerable intake for adults for arsenic recommended by WHO.

  8. An integrated crop- and soil-based strategy for variable-rate nitrogen management in corn

    NASA Astrophysics Data System (ADS)

    Roberts, Darrin F.

    Nitrogen (N) management in cereal crops has been the subject of considerable research and debate for several decades. Historic N management practices have contributed to low nitrogen use efficiency (NUE). Low NUE can be caused by such things as poor synchronization between soil N supply and crop demand, uniform application rates of fertilizer N to spatially variable landscapes, and failure to account for temporally variable influences on soil N supply and crop N need. Active canopy reflectance sensors and management zones (MZ) have been studied separately as possible plant- and soil-based N management tools to increase NUE. Recently, some have suggested that the integration of these two approaches would provide a more robust N management strategy that could more effectively account for soil and plant effects on crop N need. For this reason, the goal of this research was to develop an N application strategy that would account for spatial variability in soil properties and use active canopy reflectance sensors to determine in-season, on-the-go N fertilizer rates, thereby increasing NUE and economic return for producers over current N management practices. To address this overall goal, a series of studies were conducted to better understand active canopy sensor use and explore the possibility of integrating spatial soil data with active canopy sensors. Sensor placement to assess crop N status was first examined. It was found that the greatest reduction in error over sensing each individual row for a hypothetical 24-row applicator was obtained with 2-3 sensors estimating an average chlorophyll index for the entire boom width. Next, use of active sensor-based soil organic matter (OM) estimation was compared to more conventional aerial image-based soil OM estimation. By adjusting regression intercept values for each field, OM could be predicted using either a single sensor or image data layer. The final study consisted of validation of the active sensor algorithm

  9. [Changes of crop yield and soil fertility under long-term application of fertilizer and recycled nutrients in manure on a black soil III. Soil nutrient budget].

    PubMed

    Liu, Hongxiang; Wang, Delu; Wang, Shouyu; Meng, Kai; Han, Xiaozeng; Zhang, Lu; Shen, Shanmin

    2002-11-01

    The nutrient budget of fertilization models under different treatments was calculated using data from a field experiment over the period of 1985-1999. The results indicated that application of nitrogen fertilizer accelerated a large deficit of soil phosphorus, and the use of nitrogen and phosphorus accelerated the deficit of potassium. The experimental data demonstrated the appearance of a large area of soil deficit of phosphorus from 1970s and of potassium from 1980s in China. Nutrient recycled in farming system improved soil nutrient budget, but could not meet the nutrient requirements from high-yield crops. The use of recycled nutrients with an appropriate use of fertilizers according to the soil fertility could produce higher crop yields, balance soil nutrient budget, and not cause surplus nutrients to emit into environment.

  10. Mycotrophy of crops in rotation and soil amendment with peat influence the abundance and effectiveness of indigenous arbuscular mycorrhizal fungi in field soil.

    PubMed

    Vestberg, M; Saari, K; Kukkonen, S; Hurme, T

    2005-09-01

    Mycotrophy of previous crops has been shown to have an impact on arbuscular mycorrhizal fungi (AMF), and the growth and productivity of succeeding crops. We studied the impact of 3 years of cultivation of eight crops with different degrees of mycotrophy, including mycorrhizal (strawberry, rye, timothy, onion, caraway) and non-mycorrhizal (turnip rape, buckwheat, fiddleneck) hosts, as well as the impact of peat amendment, on the effectiveness, amount and diversity of indigenous AMF. A field experiment having a split-plot design with peat amendment as the main plot, crop cultivation as a sub-plot and three replications, was carried out on silt clay mineral soil in 1999-2001. A well-humified dark peat was applied immediately before establishment of the field experiment. Each year, the relative mycorrhizal effectiveness of soil collected in September, in terms of shoot dry weight (RME(DW)), was determined in a bioassay. In the 3rd year of the experiment, AMF spores were also extracted and identified from the field soil. Expressed as the mean of 3 years of cropping in unamended soil, the mycorrhizal crops strawberry and caraway maintained RME(DW) most effectively, while the values were lower in the non-host crops buckwheat, turnip rape and fiddleneck. In addition, the numbers of AM spores detected in soil were considerably greater during 3 years of strawberry cultivation. In soil under caraway, there were high numbers of AM spores compared to the other crops. In soil amended with peat, the situation was in some cases opposite of that of unamended soil; RME(DW) was highest in rye and onion and lowest in strawberry and caraway. The reasons behind the negative impact of peat on mycorrhizal effectiveness in strawberry soil may be due to the microbiological properties of peat. The importance of including mycotrophic species in crop rotations for maintaining high soil quality and for increasing yields of subsequent crops is discussed.

  11. Root traits and soil properties in harvested perennial grassland, annual wheat, and never-tilled annual wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background and aims: Root functional traits are determinants of soil carbon storage; plant productivity; and ecosystemproperties. However, few studies look at both annual and perennial roots, soil properties, and productivity in the context of field scale agricultural systems. Methods: In Long Term...

  12. Modeling the annual soil erosion rate in the mouth of river Pineios' sub-basin in Thessaly County, Greece.

    NASA Astrophysics Data System (ADS)

    Ilia, Ioanna; Loupasakis, Constantinos; Tsangaratos, Paraskevas

    2015-04-01

    Erosion is a natural - geomorphological phenomenon, active through geological time that is considered as one of the main agents that forms the earth surface. Soil erosion models estimate the rates of soil erosion and provide useful information and guidance for the development of appropriate intervention and soil conservation practices and strategies. A significant number of soil erosion models can be found in literature; however, the most extensively applied model is the Revised Universal Soil Loss Equation (RUSLE) established in 1997 by Renard KG, Foster GR, Weesies GA, McCool DK and Yoder DC. RUSLE is an empirically based model that enables the estimation of the average annual rate of soil erosion for an area of interest providing several alternative scenarios involving cropping systems, management methods and erosion control strategies. According to RUSLE model's specifications five major factors (rainfall pattern, soil type, topography, crop system, and management practices) are utilized for estimating the average annual erosion through the following equation: A=RxKxLxSxCxP, PIC where A is the computed spatial average soil loss and temporal average soil loss per unit area (tons ha-1 year-1), R the rainfall-runoff erosivity factor (MJ mm ha-1h-1 year-1), K the soil erodibility factor (tons h MJ-1 mm-1), L the slope - length factor, S the slope steepness factor, C the cover management factor and P the conservation support practice factor. L, S, C and P factors are all dimensionless. The present study aims to utilize a GIS-based RUSLE model in order to estimate the average annual soil loss rate in the sub-basin extending at the mouth of Pineios river in Thessaly County, Greece. The area covers approximate 775.9 km2 with a mean slope angle of 7.8o. The rainfall data of 39 gauge station from 1980 to 2000 where used in order to predict the rainfall-runoff erosivity factor (R). The K-factor was estimated using soil maps available from the European Soil Portal with a

  13. Soil Microbial Substrate Properties and Microbial Community Responses under Irrigated Organic and Reduced-Tillage Crop and Forage Production Systems

    PubMed Central

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

    2014-01-01

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

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

    PubMed

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

    2014-01-01

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

  15. Intercropping of aromatic crop Pelargonium graveolens with Solanum tuberosum for better productivity and soil health.

    PubMed

    Vermal, Rajesh Kumar; Yadav, Ajai; Verma, Ram Swaroop; Khan, Khushboo

    2014-11-01

    Farmers in hilly regions experience low production potential and resource use efficiency due to low valued crops and poorsoil health. Geranium (Pelargonium graveolens L.) is a vegetatively propagated initially slow growing, high value aromatic crop. Potato (Solanum tuberosum L.) is also vegetatively propagated high demand cash crop. A field experiment was carried out in temperate climate to investigate the influence of geranium intercropping at different row strips (1:1 and 1:2) and plant density (60 x 45, 75 x 45 and 90 x 45 cm) with potato intercrop on biomass, oil yield, monetary advantage and soil quality parameters. The row spacing 60x45cm and row strip 1:1 was found to be superior and produced 92 t ha(-1) and 14 kg ha(-1) biomass and oil yield, respectively. The row strip 1:2 intercrop earned a maximum $2107, followed by $1862 with row strip 1:1 at 60 x 45 cm plant density. Significant variations were noticed in soil organic carbon (Corg), total N (Nt), available nutrients, soil microbial biomass (Cmic) and nitrogen (Nmic) content. Maximum improvement of Corg (41.0%) and Nt (27.5%)with row strip 1:1 at 75 x 45 cm plant density. While higher soil respiration rate, Cmic, Nmic, and qCO2 was found with 1:2 row strip at 60 x 45 plant density. The buildup of Corg and Cmic potato intercrop can promote long term sustainability on productivity and soil health.

  16. Soil physical and hydrological properties under three biofuel crops in Ohio

    SciTech Connect

    Bonin, Catherine; Lal, Dr. Rattan; Schmitz, Matthias

    2012-01-01

    While biofuel crops are widely studied and compared for their energy and carbon footprints, less is known about their effects on other soil properties, particularly hydrologic characteristics. Soils under three biofuel crops, corn (Zea mays), switchgrass (Panicum virgatum), and willow (Salix spp.), were analyzed seven years after establishment to assess the effects on soil bulk density ({rho}{sub b}), penetration resistance (PR), water-holding capacity, and infiltration characteristics. The PR was the highest under corn, along with the lowest associated water content, while PR was 50-60% lower under switchgrass. In accordance with PR data, surface (0-10 cm) bulk density also tended to be lower under switchgrass. Both water infiltration rates and cumulative infiltration amounts varied widely among and within the three crops. Because the Philip model did not fit the data, results were analyzed using the Kostiakov model instead. Switchgrass plots had an average cumulative infiltration of 69 cm over 3 hours with a constant infiltration rate of 0.28 cm min{sup -1}, compared with 37 cm and 0.11 cm min{sup -1} for corn, and 26 cm and 0.06 cm min{sup -1} for willow, respectively. Results suggest that significant changes in soil physical and hydrologic properties may require more time to develop. Soils under switchgrass may have lower surface bulk density, higher field water capacity, and a more rapid water infiltration rate than those under corn or willow.

  17. Impact of different bioenergy crops on N-cycling bacterial and archaeal communities in soil.

    PubMed

    Mao, Yuejian; Yannarell, Anthony C; Davis, Sarah C; Mackie, Roderick I

    2013-03-01

    Biomass production for bioenergy may change soil microbes and influence ecosystem properties. To explore the impact of different bioenergy cropping systems on soil microorganisms, the compositions and quantities of soil microbial communities (16S rRNA gene) and N-cycling functional groups (nifH, bacterial amoA, archaeal amoA and nosZ genes) were assessed under maize, switchgrass and Miscanthus x giganteus at seven sites representing a climate gradient (precipitation and temperature) in Illinois, USA. Overall, the site-to-site variation in community composition surpassed the variation due to plant type, and microbial communities under each crop did not converge on a 'typical' species assemblage. Fewer than 5% of archaeal amoA, bacterial amoA, nifH and nosZ OTUs were significantly different among these crops, but the largest differences observed at each site were found between maize and the two perennial grasses. Quantitative PCR revealed that the abundance of the nifH gene was significantly higher in the perennial grasses than in maize, and we also found significantly higher total N in the perennial grass soils than in maize. Thus, we conclude that cultivation of these perennial grasses, instead of maize, as bioenergy feedstocks can improve soil ecosystem nitrogen sustainability by increasing the population size of N-fixing bacteria.

  18. AgRISTARS: Soil moisture/early warning and crop condition assessment. Interface control document

    NASA Technical Reports Server (NTRS)

    1980-01-01

    The interactions and support functions required between the early warning/crop condition assessment (EW/CCA) project and soil moisture (SM) project are defined. The EW Project aims to develop, test and evaluate techniques and procedures for adapting remote sensing technology to provide early warning of events and the timely assessment of those factors which affect the quality and quantity of production of economically important crops. Those techniques to augment and reinforce the current assessment activities are to be developed to improve the definition of the relationship between the plant(s) and its environment. This assessment and evaluation will certainly include the need for soil moisture measurement and estimation. The SM Project aims to develop, test, and evaluate techniques and procedures to measure or predict soil moisture in the root zone using both contact and remote sensors.

  19. Influence of soil reaction on diversity and antifungal activity of fluorescent pseudomonads in crop rhizospheres.

    PubMed

    Verma, Rajni; Naosekpam, Ajit Singh; Kumar, Sanjay; Prasad, Ramdeen; Shanmugam, V

    2007-05-01

    The diversity and antifungal activity of fluorescent pseudomonads isolated from rhizospheres of tea, gladiolus, carnation and black gram grown in acidic soils with similar texture and climatic conditions were studied. Biochemical characterisation including antibiotic resistance assay, RAPD and PCR-RFLP studies revealed a largely homogenous population. At soil pH (5.2), the isolates exhibited growth with varying levels of siderophore production, irrespective of crop rhizospheres. Two isolates with maximum chitinase production showed antagonism. The bacterial populations in general lacked the ability to produce deleterious traits such as cellulase, pectinase and hydrogen cyanide. However, increased pH levels beyond 5.2 caused reduction in metabolite production with reduced antifungal activity. The homogeneity of the bacterial population irrespective of crop rhizospheres together with decreased secondary metabolite production at higher pH levels reinstated the importance of soil over host plant in influencing rhizosphere populations. The studies also yielded acid tolerant chitinase producing antagonistic fluorescent pseudomonads.

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

    SciTech Connect

    Gregg, Jay S.; Izaurralde, Roberto C.

    2010-08-26

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

  1. Removal of arsenic from Janghang smelter site and energy crops-grown soil with soil washing using magnetic iron oxide

    NASA Astrophysics Data System (ADS)

    Han, Jaemaro; Zhao, Xin; Lee, Jong Keun; Kim, Jae Young

    2014-05-01

    Arsenic compounds are considered carcinogen and easily enter drinking water supplies with their natural abundance. US Environmental Protection Agency is finalizing a regulation to reduce the public health risks from arsenic in drinking water by revising the current drinking water standard for arsenic from 50 ppb to 10 ppb in 2001 (USEPA, 2001). Therefore, soil remediation is also growing field to prevent contamination of groundwater as well as crop cultivation. Soil washing is adjusted as ex-situ soil remediation technique which reduces volume of the contaminated soil. The technique is composed of physical separation and chemical extraction to extract target metal contamination in the soil. Chemical extraction methods have been developed solubilizing contaminants containing reagents such as acids or chelating agents. And acid extraction is proven as the most commonly used technology to treat heavy metals in soil, sediment, and sludge (FRTR, 2007). Due to the unique physical and chemical properties, magnetic iron oxide have been used in diverse areas including information technology and biomedicine. Magnetic iron oxides also can be used as adsorbent to heavy metal enhancing removal efficiency of arsenic concentration. In this study, magnetite is used as the washing agent with acid extraction condition so that the injected oxide can be separated by magnetic field. Soil samples were collected from three separate areas in the Janghang smelter site and energy crops-grown soil to have synergy effect with phytoremediation. Each sample was air-dried and sieved (2mm). Soil washing condition was adjusted on pH in the range of 0-12 with hydrogen chloride and sodium hydroxide. After performing soil washing procedure, arsenic-extracted samples were analyzed for arsenic concentration by inductively coupled plasma optical emission spectrometer (ICP-OES). All the soils have exceeded worrisome level of soil contamination for region 1 (25mg/kg) so the soil remediation techniques are

  2. Implementation of Sustainable Soil Management Practices to Improve Crop Production in the Different Ethiopian Agro Systems

    NASA Astrophysics Data System (ADS)

    García Moreno, R.; Gameda, S.; Diaz Alvarez, M. C.; Selasie, Y. G.

    2012-04-01

    Agriculture in Ethiopia is one of first priority since close to 10 In this context, the Ethiopian crop production faces to the following soil management challenges: lack of updated soil data, macro and micro nutrient depletion, acidity, salinity and soil surface erosion and crusting. One of the biggest issues is the loss of arable land, above 137 T/yr, reaching during some particularly dried periods until 300 T/yr. In this context, the authors constituted a working group of experts from Spanish and Ethiopian universities, local producers and international and governmental organisms to analyse the problems related to the different agro ecological zones found in Ethiopia and the management practices of different local producers. The study produced the trends to implement in the different areas to improve soil management practices in order to contribute to increase the crop production mainly to achieve food security problems. The analyse produced different working fields for the next years for addressing soil degradation, improving land resources management practices, increasing agricultural productivity, updating the available soil data, developing an international program of education, transferring of knowledge from similar study cases and implementing economical tools to help producers to assure income after severe edapho-climatic events. The practical work and the projects developed for the next period is addressed to smallholder farms belonging to the different 34 agro ecological zones identified in Ethiopia, each of them with very specific environmental, cultural and soil management practices.

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

    PubMed

    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.

  4. Soil properties and not inputs control carbon : nitrogen : phosphorus ratios in cropped soils in the long term

    NASA Astrophysics Data System (ADS)

    Frossard, Emmanuel; Buchmann, Nina; Bünemann, Else K.; Kiba, Delwende I.; Lompo, François; Oberson, Astrid; Tamburini, Federica; Traoré, Ouakoltio Y. A.

    2016-02-01

    Stoichiometric approaches have been applied to understand the relationship between soil organic matter dynamics and biological nutrient transformations. However, very few studies have explicitly considered the effects of agricultural management practices on the soil C : N : P ratio. The aim of this study was to assess how different input types and rates would affect the C : N : P molar ratios of bulk soil, organic matter and microbial biomass in cropped soils in the long term. Thus, we analysed the C, N, and P inputs and budgets as well as soil properties in three long-term experiments established on different soil types: the Saria soil fertility trial (Burkina Faso), the Wagga Wagga rotation/stubble management/soil preparation trial (Australia), and the DOK (bio-Dynamic, bio-Organic, and "Konventionell") cropping system trial (Switzerland). In each of these trials, there was a large range of C, N, and P inputs which had a strong impact on element concentrations in soils. However, although C : N : P ratios of the inputs were highly variable, they had only weak effects on soil C : N : P ratios. At Saria, a positive correlation was found between the N : P ratio of inputs and microbial biomass, while no relation was observed between the nutrient ratios of inputs and soil organic matter. At Wagga Wagga, the C : P ratio of inputs was significantly correlated to total soil C : P, N : P, and C : N ratios, but had no impact on the elemental composition of microbial biomass. In the DOK trial, a positive correlation was found between the C budget and the C to organic P ratio in soils, while the nutrient ratios of inputs were not related to those in the microbial biomass. We argue that these responses are due to differences in soil properties among sites. At Saria, the soil is dominated by quartz and some kaolinite, has a coarse texture, a fragile structure, and a low nutrient content. Thus, microorganisms feed on inputs (plant residues, manure). In contrast, the soil at

  5. Maximum temperature accounts for annual soil CO2 efflux in temperate forests of Northern China.

    PubMed

    Zhou, Zhiyong; Xu, Meili; Kang, Fengfeng; Jianxin Sun, Osbert

    2015-07-16

    It will help understand the representation legality of soil temperature to explore the correlations of soil respiration with variant properties of soil temperature. Soil temperature at 10 cm depth was hourly logged through twelve months. Basing on the measured soil temperature, soil respiration at different temporal scales were calculated using empirical functions for temperate forests. On monthly scale, soil respiration significantly correlated with maximum, minimum, mean and accumulated effective soil temperatures. Annual soil respiration varied from 409 g C m(-2) in coniferous forest to 570 g C m(-2) in mixed forest and to 692 g C m(-2) in broadleaved forest, and was markedly explained by mean soil temperatures of the warmest day, July and summer, separately. These three soil temperatures reflected the maximum values on diurnal, monthly and annual scales. In accordance with their higher temperatures, summer soil respiration accounted for 51% of annual soil respiration across forest types, and broadleaved forest also had higher soil organic carbon content (SOC) and soil microbial biomass carbon content (SMBC), but a lower contribution of SMBC to SOC. This added proof to the findings that maximum soil temperature may accelerate the transformation of SOC to CO2-C via stimulating activities of soil microorganisms.

  6. Soil Moisture Anomaly as Predictor of Crop Yield Deviation in Germany

    NASA Astrophysics Data System (ADS)

    Peichl, Michael; Thober, Stephan; Schwarze, Reimund; Meyer, Volker; Samaniego, Luis

    2016-04-01

    Natural hazards, such as droughts, have the potential to drastically diminish crop yield in rain-fed agriculture. For example, the drought in 2003 caused direct losses of 1.5 billion EUR only in Germany (COPA-COGECA 2003). Predicting crop yields allows to economize the mitigation of risks of weather extremes. Economic approaches for quantifying agricultural impacts of natural hazards mainly rely on temperature and related concepts. For instance extreme heat over the growing season is considered as best predictor of corn yield (Auffhammer and Schlenker 2014). However, those measures are only able to provide a proxy for the available water content in the root zone that ultimately determines plant growth and eventually crop yield. The aim of this paper is to analyse whether soil moisture has a causal effect on crop yield that can be exploited in improving adaptation measures. For this purpose, reduced form fixed effect panel models are developed with yield as dependent variable for both winter wheat and silo maize crops. The explanatory variables used are soil moisture anomalies, precipitation and temperature. The latter two are included to estimate the current state of the water balance. On the contrary, soil moisture provides an integrated signal over several months. It is also the primary source of water supply for plant growth. For each crop a single model is estimated for every month within the growing period to study the variation of the effects over time. Yield data is available for Germany as a whole on the level of administrative districts from 1990 to 2010. Station data by the German Weather Service are obtained for precipitation and temperature and are aggregated to the same spatial units. Simulated soil moisture computed by the mesoscale Hydrologic Model (mHM, www.ufz.de/mhm) is transformed into Soil Moisture Index (SMI), which represents the monthly soil water quantile and hence accounts directly for the water content available to plants. The results

  7. Food crop accumulation and bioavailability assessment for antimony (Sb) compared with arsenic (As) in contaminated soils.

    PubMed

    Wilson, Susan C; Tighe, Matthew; Paterson, Ewan; Ashley, Paul M

    2014-10-01

    Field samples and a 9-week glasshouse growth trial were used to investigate the accumulation of mining derived arsenic (As) and antimony (Sb) in vegetable crops growing on the Macleay River Floodplain in Northern New South Wales, Australia. The soils were also extracted using EDTA to assess the potential for this extractant to be used as a predictor of As and Sb uptake in vegetables, and a simplified bioaccessibility extraction test (SBET) to understand potential for uptake in the human gut with soil ingestion. Metalloids were not detected in any field vegetables sampled. Antimony was not detected in the growth trial vegetable crops over the 9-week greenhouse trial. Arsenic accumulation in edible vegetable parts was <10 % total soil-borne As with concentrations less than the current Australian maximum residue concentration for cereals. The results indicate that risk of exposure through short-term vegetable crops is low. The data also demonstrate that uptake pathways for Sb and As in the vegetables were different with uptake strongly impacted by soil properties. A fraction of soil-borne metalloid was soluble in the different soils resulting in Sb soil solution concentration (10.75 ± 0.52 μg L(-1)) that could present concern for contamination of water resources. EDTA proved a poor predictor of As and Sb phytoavailability. Oral bioaccessibility, as measured by SBET, was <7 % for total As and <3 % total Sb which is important to consider when estimating the real risk from soil borne As and Sb in the floodplain environment.

  8. Effects of herbicide and insecticide interaction on soil entomofauna under maize crop.

    PubMed

    Pereira, Jardel Lopes; da Silva, Antonio Alberto; Picanço, Marcelo Coutinho; de Barros, Emerson Cristi; Jakelaitis, Adriano

    2005-01-01

    The aim of this study was to evaluate the impact of the herbicide mixture nicosulfuron + atrazine, with or without the insecticide chlorpyrifos, onto soil entomofauna under maize crop. The treatments, applied 25 days after maize emergence, were represented by a weeded control without insecticide and herbicide, a weeded control with chlorpyrifos, and mixtures of nicosulfuron + atrazine, with or without chlorpyrifos. Arthropods populations, on the soil surface, as well as inside the soil under maize, were principally represented by mites (Arachnida: Acari), decomposer collembolans (Hexapoda:Parainsecta:Collembola) and predator ants (Hymenoptera:Formicidae). The nicosulfuron + atrazine mixture with chlorpyrifos and the isolated chlorpyrifos reduced the population dynamics of all insect groups on the soil surface compared to the weeded control. In the soil, mite and ant populations were reduced after application of the herbicide mixture with chlorpyrifos and of the isolated chlorpyrifos.

  9. Soil, Water, and Greenhouse-gas Impacts of Alternative Biomass Cropping Systems

    NASA Astrophysics Data System (ADS)

    Schulte Moore, L. A.; Bach, E.; Cambardella, C.; Hargreaves, S.; Helmers, M.; Hofmockel, K.; Isenhart, T.; Kolka, R. K.; Ontl, T.; Welsh, W.; Williams, R.; Landscape Biomass Team

    2010-12-01

    Through the 2008 Energy Independence and Security Act and other state and federal mandates, the U.S. is embarking on an aggressive agenda to reduce dependency on fossil fuels. While grain-derived ethanol will be used to largely meet initial renewable fuels targets, advanced biofuels derived from lignocellulosic materials are expected to comprise a growing proportion of the renewable energy portfolio and provide a more sustainable solution. As part of our interdisciplinary research, we are assessing the environmental impacts of four lignocellulosic biomass cropping systems and comparing them to a conventional corn cropping system. This comparison is conducted using a randomized, replicated experiment initiated in fall 2008, which compares the five cropping systems across a toposequence (i.e., floodplain, toeslope, backslope, shoulder, summit). In addition to assessing herbaceous and woody biomass yields, we are evaluating the environmental performance of these systems through changes in water quality, greenhouse-gas emissions, and carbon pools. Initial results document baseline soil parameters, including the capacity of the soils to sequester carbon across the toposequence, and the impacts of landscape heterogeneity and cropping system on soil moisture and nitrate-nitrogen levels in the vadose zone. Additional results on greenhouse-gas emissions and carbon dynamics are forthcoming from this year’s field research. The fuller understanding of the environmental performance of these systems will help inform federal and state policies seeking to incentivize the development of a sustainable bioenergy industry.

  10. Biogas digestates affect crop P uptake and soil microbial community composition.

    PubMed

    Hupfauf, Sebastian; Bachmann, Silvia; Fernández-Delgado Juárez, Marina; Insam, Heribert; Eichler-Löbermann, Bettina

    2016-01-15

    Fermentation residues from biogas production are known as valuable organic fertilisers. This study deals with the effect of cattle slurry, co-digested cattle slurry, co-digested energy crops and mineral fertilisers on the activity and composition of soil microbiota. Furthermore, the effect of solid-liquid separation as a common pre-treatment of digestate was tested. The fertilising effects were analysed in an 8-week pot experiment on loamy sand using two crops, Amaranthus cruentus and Sorghum bicolor. Amaranth, as a crop with significantly higher P uptake, triggered stress for occurring soil microbes and thereby caused a reduction of microbial biomass C in the soil. Irrespective of the crop, microbial basal respiration and metabolic quotient were higher with the digestates than with the untreated slurry or the mineral treatments. Community level physiological profiles with MicroResp showed considerable differences among the treatments, with particularly strong effects of solid-liquid separation. Similar results were also found on a structural level (PCR-DGGE). Alkaline phosphatase gene analyses revealed high sensitivity to different fertilisation regimes.

  11. Effects of soil moisture depletion on vegetable crop uptake of pharmaceuticals and personal care products (PPCPs).

    PubMed

    Santiago, Sergio; Roll, Deborah M; Ray, Chittaranjan; Williams, Clinton; Moravcik, Philip; Knopf, Allan

    2016-10-01

    Agricultural crops have a long history of being irrigated with recycled wastewater (RW). However, its use on vegetable crops has been of concern due to the potential prevalence of microcontaminants, such as pharmaceuticals and personal care products (PPCPs) in the latter, which represents a possible health hazard to consumers. We investigated the uptake of three PPCPs (atenolol, diclofenac, and ofloxacin), at three different concentrations in irrigation water (0.5, 5, and 25 μg L(-1)) in relation to three varying volumetric soil moisture depletion levels of 14 % (-4.26 kPa), 10 % (-8.66 kPa), and 7 % (-18.37 kPa) by various vegetable crop species. Experiments were conducted in a split-split block completely randomized design. PPCPs were extracted using a developed method of accelerated solvent extraction and solid phase extraction and analyzed via liquid chromatography mass spectrometry (LCMS). Results indicate that all treated crops were capable of PPCP uptake at nanogram per gram concentrations independent of the applied soil moisture depletion levels and PPCP concentrations. Ofloxacin was the chemical with the highest uptake amounts, followed by atenolol and then diclofenac. Although the results were not statistically significant, higher concentrations of PPCPs were detected in plants maintained under higher soil moisture levels of 14 % (-4.26 kPa).

  12. Crop residue management and fertilization effects on soil organic matter and associated biological properties.

    PubMed

    Zhao, Bingzi; Zhang, Jiabao; Yu, Yueyue; Karlen, Douglas L; Hao, Xiying

    2016-09-01

    Returning crop residue may result in nutrient reduction in soil in the first few years. A two-year field experiment was conducted to assess whether this negative effect is alleviated by improved crop residue management (CRM). Nine treatments (3 CRM and 3 N fertilizer rates) were used. The CRM treatments were (1) R0: 100 % of the N using mineral fertilizer with no crop residues return; (2) R: crop residue plus mineral fertilizer as for the R0; and (3) Rc: crop residue plus 83 % of the N using mineral and 17 % manure fertilizer. Each CRM received N fertilizer rates at 270, 360, and 450 kg N ha(-1) year(-1). At the end of the experiment, soil NO3-N was reduced by 33 % from the R relative to the R0 treatment, while the Rc treatment resulted in a 21 to 44 % increase in occluded particulate organic C and N, and 80 °C extracted dissolved organic N, 19 to 32 % increase in microbial biomass C and protease activity, and higher monounsaturated phospholipid fatty acid (PLFA):saturated PLFA ratio from stimulating growth of indigenous bacteria when compared with the R treatment. Principal component analysis showed that the Biolog and PLFA profiles in the three CRM treatments were different from each other. Overall, these properties were not influenced by the used N fertilizer rates. Our results indicated that application of 17 % of the total N using manure in a field with crop residues return was effective for improving potential plant N availability and labile soil organic matter, primarily due to a shift in the dominant microorganisms.

  13. Molybdenum uptake by forage crops grown on sewage sludge -- Amended soils in the field and greenhouse

    SciTech Connect

    McBride, M.B.; Richards, B.K.; Steenhuis, T.; Spiers, G.

    2000-06-01

    Molybdenum (Mo) is a plant-available element in soils that can adversely affect the health of farm animals. There is a need for more information on its uptake into forage crops from waste materials, such as sewage sludge, applied to agricultural land. Field and greenhouse experiments with several crops grown on long-term sewage sludge-amended soils as well as soils recently amended with dewatered (DW) and alkaline-stabilized (ALK) sludges indicated that Mo supplied from sludge is readily taken up by legumes in particular. Excessive uptake into red clover (Trifolium pratense L.) was seen in a soil that had been heavily amended with sewage sludge 20 yr earlier, where the soil contained about 3 mg Mo/kg soil, three times the background soil concentration. The greenhouse and field studies indicated that Mo can have a long residual availability in sludge-amended soils. The effect of sludge application was to decrease Cu to Mo ratios in legume forages, canola (Brassica napus var. napus) and soybeans [Glycine max (L.) Merr.] below the recommended limit of 2:1 for ruminant diets, a consequence of high bioavailability of Mo and low uptake of Cu added in sludge. Molybdenum uptake coefficients (UCs) for ALK sludge were higher than for DW sludge, presumably due to the greater solubility of Mo measured in the more alkaline sludges and soils. Based on these UCs, it is tentatively recommended that cumulative Mo loadings on forages grown on nonacid soils should not exceed 1.0 kg/ha from ALK sludge or 4.0 kg/ha from DW sludge.

  14. Effects of long-term irrigation with untreated municipal wastewater on soil properties and crop quality.

    PubMed

    Aydin, Mehmet Emin; Aydin, Senar; Beduk, Fatma; Tor, Ali; Tekinay, Arzu; Kolb, Marit; Bahadir, Müfit

    2015-12-01

    Irrigating crops with untreated wastewater leads to elevated concentrations of heavy metals both in soil and cultivated crops. The current study was designed to determine heavy metal (i.e., Pb, Cd, Cr, Cu, Ni, Zn, Hg) accumulation in Konya soils in selected nine sites irrigated with wastewater for over 40 years. Non-irrigated soil samples and soil samples irrigated with well water were taken as control samples. Transport of these pollutants to the wheat samples cultivated in the investigated site was also examined. The obtained results reveal that high alkaline properties and clay structure of Konya soil reduce the mobility of contaminants and cause accumulation in the top layer of soil. Intense effect of wastewater irrigation on soil EC was determined. The highest concentrations of Pb, Cr, Cu, Cd, Zn, Ni, and Hg in wastewater irrigated soil were 5.32, 37.1, 31.5, 11.4, 91.5, 134, and 0.34 mg kg(-1), respectively. Wastewater irrigated soils were strongly polluted by means of Cd (8.23-11.6 mg kg(-1)) and moderately to strongly polluted by means of Ni (47.7-134 mg kg(-1)), exceeding Maximum Admissible Concentrations for Trace Elements in Agricultural Soils and Sewage Sludge Regulation limit values of Turkey. Maximum concentrations found for Pb, Cr, Cu, Cd, Zn, and Ni in wastewater irrigated wheat grain were 8.44, 1.30, 9.10, n.d, 29.31, and 0.94 mg kg(-1), respectively. Besides, Hg was not detected in any samples of wheat grain. Based on the regulation of Turkish Food Codex, Pb contamination in wheat samples grown in the sampling site was evidenced.

  15. The potential of agricultural practices to increase C storage in cropped soils: an assessment for France

    NASA Astrophysics Data System (ADS)

    Chenu, Claire; Angers, Denis; Métay, Aurélie; Colnenne, Caroline; Klumpp, Katja; Bamière, Laure; Pardon, Lenaic; Pellerin, Sylvain

    2014-05-01

    Though large progress has been achieved in the last decades, net GHG emissions from the agricultural sector are still more poorly quantified than in other sectors. In this study, we examined i) technical mitigation options likely to store carbon in agricultural soils, ii) their potential of additional C storage per unit surface area and iii) applicable areas in mainland France. We considered only agricultural practices being technically feasible by farmers and involving no major change in either production systems or production levels. Moreover, only currently available techniques with validated efficiencies and presenting no major negative environmental impacts were taken into account. Four measures were expected to store additional C in agricultural soils: - Reducing tillage: either a switch to continuous direct seeding, direct seeding with occasional tillage once every five years, or continuous superficial (<15 cm) tillage. - Introducing cover crops in cropping systems: sown between two cash crops on arable farms, in orchards and vineyards (permanent or temporary cover cropping) . - Expanding agroforestry systems; planting of tree lines in cultivated fields and grasslands, and hedges around the field edges. - Increasing the life time of temporary sown grasslands: increase of life time to 5 years. The recent literature was reviewed in order to determine long term (>20yrs) C storage rates (MgC ha-1 y-1,) of cropping systems with and without the proposed practice. Then we analysed the conditions for potential application, in terms of feasibility, acceptance, limitation of yield losses and of other GHG emissions. According to the literature, additional C storage rates were 0.15 (0-0.3) MgC ha-1 y-1 for continuous direct seeding, 0.10 (0-0.2) MgC ha-1 y-1for occasional tillage one year in five, and 0.0 MgC ha-1 y-1 for superficial tillage. Cover crops were estimated to store 0.24 (0.13-0.37) MgC ha-1 y-1 between cash crops and 0.49 (0.23-0.72) MgC ha-1 y-1 when

  16. The Effect of Long-Term Continuous Cropping of Black Pepper on Soil Bacterial Communities as Determined by 454 Pyrosequencing.

    PubMed

    Xiong, Wu; Li, Zhigang; Liu, Hongjun; Xue, Chao; Zhang, Ruifu; Wu, Huasong; Li, Rong; Shen, Qirong

    2015-01-01

    In the present study, 3 replanted black pepper orchards with continuously cropping histories for 10, 21, and 55 years in tropical China, were selected for investigating the effect of monoculture on soil physiochemical properties, enzyme activities, bacterial abundance, and bacterial community structures. Results showed long-term continuous cropping led to a significant decline in soil pH, organic matter contents, enzymatic activities, and resulted in a decrease in soil bacterial abundance. 454 pyrosequencing analysis of 16S rRNA genes revealed that the Acidobacteria and Proteobacteria were the main phyla in the replanted black pepper orchard soils, comprising up to 73.82% of the total sequences; the relative abundances of Bacteroidetes and Firmicutes phyla decreased with long-term continuous cropping; and at genus level, the Pseudomonas abundance significantly depleted after 21 years continuous cropping. In addition, bacterial diversity significantly decreased after 55 years black pepper continuous cropping; obvious variations for community structures across the 3 time-scale replanted black pepper orchards were observed, suggesting monoculture duration was the major determinant for bacterial community structure. Overall, continuous cropping during black pepper cultivation led to a significant decline in soil pH, organic matter contents, enzymatic activities, resulted a decrease in soil bacterial abundance, and altered soil microbial community membership and structure, which in turn resulted in black pepper poor growth in the continuous cropping system.

  17. The Effect of Long-Term Continuous Cropping of Black Pepper on Soil Bacterial Communities as Determined by 454 Pyrosequencing

    PubMed Central

    Xiong, Wu; Li, Zhigang; Liu, Hongjun; Xue, Chao; Zhang, Ruifu; Wu, Huasong; Li, Rong; Shen, Qirong

    2015-01-01

    In the present study, 3 replanted black pepper orchards with continuously cropping histories for 10, 21, and 55 years in tropical China, were selected for investigating the effect of monoculture on soil physiochemical properties, enzyme activities, bacterial abundance, and bacterial community structures. Results showed long-term continuous cropping led to a significant decline in soil pH, organic matter contents, enzymatic activities, and resulted in a decrease in soil bacterial abundance. 454 pyrosequencing analysis of 16S rRNA genes revealed that the Acidobacteria and Proteobacteria were the main phyla in the replanted black pepper orchard soils, comprising up to 73.82% of the total sequences; the relative abundances of Bacteroidetes and Firmicutes phyla decreased with long-term continuous cropping; and at genus level, the Pseudomonas abundance significantly depleted after 21 years continuous cropping. In addition, bacterial diversity significantly decreased after 55 years black pepper continuous cropping; obvious variations for community structures across the 3 time-scale replanted black pepper orchards were observed, suggesting monoculture duration was the major determinant for bacterial community structure. Overall, continuous cropping during black pepper cultivation led to a significant decline in soil pH, organic matter contents, enzymatic activities, resulted a decrease in soil bacterial abundance, and altered soil microbial community membership and structure, which in turn resulted in black pepper poor growth in the continuous cropping system. PMID:26317364

  18. Effects of changes in land use on soil physical properties and soil organic carbon content in a wheat-corn-sunflower crop sequence, in a loam soil of Argentina.

    NASA Astrophysics Data System (ADS)

    Aparicio, V.; Costa, J. L.

    2012-04-01

    The Argentinean Humid Pampas extend over about 60 million hectares, 90% of which are agricultural lands. The Southeast of the Buenos Aires Province is part of the Humid Pampas, it covers over 1,206,162 hectares, the mean annual temperature is 13.3 °C and the climate is sub-humid. At the present only 6% of the lands are used for pasture. The main activities are agriculture and cattle production. The main crops are wheat, sunflower, corn and soybean. The tillage systems used in the area are: moldboard plow (MP), chisel plow (CP) and no-till (NT). Excessive soil cultivation under MP generates decreases in the levels of soil organic carbon (SOC). The magnitude of such decrease depends on the intensity of the tillage system, the tillage timeliness and the amount and quality of the residues. Adopting NT may reduce the effects of intensive agriculture, through the maintenance and accumulation of SOC. However, there are evidences that, under NT, the bulk density (ρb) in the superficial layers of the soil increases. The soil compaction causes degradation of the soil structure, reduces the soil water availability and reduces the soil hydraulic conductivity. With this scenario and the tendency to increase the surface under NT in the Southeast Humid Pampas, we evaluated the evolution of some soil physical properties and the SOC in a 10-year experiment with a wheat-corn-sunflower rotation. The experiment was carried out in four localities at farmerś fields under three different tillage systems: MP, CP and NT in a randomized complete block design, considering each locality as a block. Each plot had 50 m in width by 100 m length and the treatments were: NT, MP and CP. The results of this experiment have allowed us to verify that: i) the wheat-corn-sunflower crop sequence showed a tendency to reduce the values of bulk density (ρb) but NT increased ρb in the superficial soil layers; ii) the more intensive the tillage system, the higher the change in the mean weight diameter

  19. Evaluating energy sorghum harvest thresholds and tillage cropping systems to offset negative environmental impacts and harvesting equipment-induced soil compaction

    NASA Astrophysics Data System (ADS)

    Meki, M. N.; Snider, J. L.; Kiniry, J. R.; Raper, R. L.; Rocateli, A. C.

    2011-12-01

    Energy sorghum (Sorghum bicolor L. Moench) could be the ideal feedstock for the cellulosic ethanol industry because of its robust establishment, broader adaptability and drought tolerance, water and nutrient use efficiency, and the relatively high annual biomass yields. Of concern, however, is the limited research data on harvest thresholds, subsequent environmental impacts and the potential cumulative effects of harvesting equipment-induced soil compaction. Indiscriminate harvests of the high volume wet energy sorghum biomass, coupled with repeated field passes, could cause irreparable damage to the soil due to compaction. Furthermore, biomass harvests result in lower soil organic matter returns to the soil, making the soil even more susceptible to soil compaction. Compacted soils result in poor root zone aeration and drainage, more losses of nitrogen from denitrification, and restricted root growth, which reduces yields. Given the many positive attributes of conservation tillage and crop residue retention, our research and extension expectations are that sustainable energy sorghum cropping systems ought to include some form of conservation tillage. The challenge is to select cropping and harvesting systems that optimize feedstock production while ensuring adequate residue biomass to sustainably maintain soil structure and productivity. Producers may have to periodically subsoil-till or plow-back their lands to alleviate problems of soil compaction and drainage, weeds, insects and disease infestations. Little, however, is known about the potential impact of these tillage changes on soil productivity, environmental integrity, and sustainability of bioenergy agro-ecosystems. Furthermore, 'safe' energy sorghum feedstock removal thresholds have yet to be established. We will apply the ALMANAC biophysical model to evaluate permissible energy sorghum feedstock harvest thresholds and the effects of subsoil tillage and periodically plowing no-tilled (NT) energy sorghum

  20. Distribution patterns of phthalic acid esters in soil particle-size fractions determine biouptake in soil-cereal crop systems

    PubMed Central

    Tan, Wenbing; Zhang, Yuan; He, Xiaosong; Xi, Beidou; Gao, Rutai; Mao, Xuhui; Huang, Caihong; Zhang, Hui; Li, Dan; Liang, Qiong; Cui, Dongyu; Alshawabkeh, Akram N.

    2016-01-01

    The use of wastewater irrigation for food crops can lead to presence of bioavailable phthalic acid esters (PAEs) in soils, which increase the potential for human exposure and adverse carcinogenic and non-cancer health effects. This study presents the first investigation of the occurrence and distribution of PAEs in a maize-wheat double-cropping system in a wastewater-irrigated area in the North China Plain. PAE levels in maize and wheat were found to be mainly attributed to PAE stores in soil coarse (250–2000 μm) and fine sand (53–250 μm) fractions. Soil particle-size fractions with higher bioavailability (i.e., coarse and fine sands) showed greater influence on PAE congener bioconcentration factors compared to PAE molecular structures for both maize and wheat tissues. More PAEs were allocated to maize and wheat grains with increased soil PAE storages from wastewater irrigation. Additional findings showed that levels of both non-cancer and carcinogenic risk for PAE congeners in wheat were higher than those in maize, suggesting that wheat food security should be prioritized. In conclusion, increased soil PAE concentrations specifically in maize and wheat grains indicate that wastewater irrigation can pose a contamination threat to food resources. PMID:27555553

  1. Distribution patterns of phthalic acid esters in soil particle-size fractions determine biouptake in soil-cereal crop systems

    NASA Astrophysics Data System (ADS)

    Tan, Wenbing; Zhang, Yuan; He, Xiaosong; Xi, Beidou; Gao, Rutai; Mao, Xuhui; Huang, Caihong; Zhang, Hui; Li, Dan; Liang, Qiong; Cui, Dongyu; Alshawabkeh, Akram N.

    2016-08-01

    The use of wastewater irrigation for food crops can lead to presence of bioavailable phthalic acid esters (PAEs) in soils, which increase the potential for human exposure and adverse carcinogenic and non-cancer health effects. This study presents the first investigation of the occurrence and distribution of PAEs in a maize-wheat double-cropping system in a wastewater-irrigated area in the North China Plain. PAE levels in maize and wheat were found to be mainly attributed to PAE stores in soil coarse (250–2000 μm) and fine sand (53–250 μm) fractions. Soil particle-size fractions with higher bioavailability (i.e., coarse and fine sands) showed greater influence on PAE congener bioconcentration factors compared to PAE molecular structures for both maize and wheat tissues. More PAEs were allocated to maize and wheat grains with increased soil PAE storages from wastewater irrigation. Additional findings showed that levels of both non-cancer and carcinogenic risk for PAE congeners in wheat were higher than those in maize, suggesting that wheat food security should be prioritized. In conclusion, increased soil PAE concentrations specifically in maize and wheat grains indicate that wastewater irrigation can pose a contamination threat to food resources.

  2. Contrasted nitrogen utilization in annual C 3 grass and legume crops: Physiological explorations and ecological considerations

    NASA Astrophysics Data System (ADS)

    Del Pozo, Alejandro; Garnier, Eric; Aronson, James

    2000-01-01

    Although it is well known that legumes have unusually high levels of nitrogen in both reproductive and vegetative organs, the physiological implications of this pattern have been poorly assessed. We conducted a literature survey and used data from two (unpublished) experiments on annual legumes and C 3 grasses in order to test whether these high nitrogen concentrations in legumes are correlated to high rates of carbon gain. Three different temporal/spatial scales were considered: full growing season/stand, days to month/whole plant and seconds/leaf. At the stand level, and for plants grown under both extratropical and tropical settings, biomass per unit organic-nitrogen was lower in legume than in grass crops. At a shorter time scale, the relative growth rate per unit plant nitrogen (`nitrogen productivity') was lower in faba bean ( Vicia faba var. minor cv. Tina) than in wheat ( Triticum aestivum cv. Alexandria), and this was confirmed in a comparison of two wild, circum-Mediterranean annuals - Medicago minima, a legume, and Bromus madritensis, a grass. Finally, at the leaf level, a synthesis of published data comparing soybean ( Glycine max) and rice ( Oryza sativa) on the one hand, and our own data on faba bean and wheat on the other hand, demonstrates that the photosynthetic rate per unit leaf nitrogen (the photosynthetic nitrogen use efficiency) is consistently lower in legumes than in grasses. These results demonstrate that, regardless of the scale considered and although the organic-nitrogen concentration in vegetative organs of legumes is higher than in grasses, this does not lead to higher rates of carbon gain in the former. Various physiological factors affecting the efficiency of nitrogen utilization at the three time scales considered are discussed. The suggestion is made that the ecological significance of the high nitrogen concentration in legumes may be related to a high nitrogen demand for high quality seed production at a time when nitrogen

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

    SciTech Connect

    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

  4. Irrigation with treated wastewater: effects on soil, lettuce (Lactuca sativa L.) crop and dynamics of microorganisms.

    PubMed

    Mañas, Pilar; Castro, Elena; de Las Heras, Jorge

    2009-10-01

    The aim of this study was to evaluate the applicability of treated wastewater for horticultural crops, assess the effects of continuous use of treated water on soil and crops, and analyse the physical, chemical and biological effects of irrigation with recycled water. Two lettuce plots watered with drinking water and treated wastewater were monitored over a three year period. Nutrients, heavy metal and the dynamics of pathogen and indicator microorganism content in soil and foliar tissues were analysed. Wastewater irrigation had a high influence on soil parameters: organic matter, N, P, Ca, Al, Fe, Pb and Zn. Indicator and pathogenic microorganisms were detected in soil and plants grown in the wastewater-irrigated plot, and persisted in the soil for 27 days during the study under humid conditions. N, P, Pb and Al content were significantly higher in plant tissues of wastewater-irrigated plots than in the control after 3 years of irrigation. Harvest was significantly higher in the wastewater-irrigated plot. Wastewater can be a resource for agricultural irrigation. In any case, the possible heavy metal accumulation in soils and presence of pathogenic organisms require careful management of this alternative resource: use of a drip irrigation system, previous wastewater disinfection and a limited irrigation period are recommended.

  5. Impact Assessment of Salinization Affected Soil on Greenhouse Crops using SALTMED

    NASA Astrophysics Data System (ADS)

    Pappa, Polyxeni; Daliakopoulos, Ioannis; Tsanis, Ioannis; Varouchakis, Emmanouil

    2015-04-01

    Here we assess the effects of soil salinization on greenhouse crops and the potential benefits of rainwater harvesting as a soil amelioration technology. The study deals with the following scenarios: (a) variation of irrigation water salinity from 3,000 μS/cm to 500 μS/cm through mixing with rainwater, (b) crop substitution for increased tolerance and (c) climatic variability to account for the impact of climate change. In order to draw meaningful conclusions, a model that takes into account vegetation interaction, soil, irrigation water and climate variables is required. The SALTMED model is a reliable and tested physical process model that simulates evapotranspiration, plant water uptake, water and solute transport to estimate crop yield and biomass production under all irrigation systems. SALTMED is tested with the above scenarios in the RECARE FP7 Project Case Study of Timpaki, in the Island of Crete, Greece. Simulations are conducted for typical cultivations of Solanum lycopersicum, Capsicum anuumm and Solanum melongena. Preliminary results indicate the optimal combination from a set of solutions concerning the soil and water parameters can be beneficial against the salinization threat. Future research includes the validation of the results with field experiments. Keywords: salinization, greenhouse, tomato, SALTMED, rainwater, RECARE

  6. [Distribution characteristics of soil profile nitrous oxide concentration in paddy fields with different rice-upland crop rotation systems].

    PubMed

    Liu, Ping-li; Zhang, Xiao-lin; Xiong, Zheng-qin; Huang, Tai-qing; Ding, Min; Wang, Jin-yang

    2011-09-01

    To investigate the dynamic distribution patterns of nitrous oxide (N2O) in the soil profiles in paddy fields with different rice-upland crop rotation systems, a special soil gas collection device was adopted to monitor the dynamics of N2O at the soil depths 7, 15, 30, and 50 cm in the paddy fields under both flooding and drainage conditions. Two rotation systems were installed, i.e., wheat-single rice and oilseed rape-double rice, each with or without nitrogen (N) application. Comparing with the control, N application promoted the N2O production in the soil profiles significantly (P < 0.01), and there existed significant correlations in the N2O concentration among the four soil depths during the whole observation period (P < 0.01). In the growth seasons of winter wheat and oilseed rape under drainage condition and with or without N application, the N2O concentrations at the soil depths 30 cm and 50 cm were significantly higher than those at the soil depths 7 cm and 15 cm; whereas in the early rice growth season under flooding condition and without N application, the N2O concentrations at the soil depth 7 cm and 15 cm were significantly higher than those at the soil depths 30 cm and 50 cm (P < 0.05). No significant differences were observed in the N2O concentrations at the test soil depths among the other rice cropping treatments. The soil N2O concentrations in the treatments without N application peaked in the transitional period from the upland crops cropping to rice planting, while those in the treatments with N application peaked right after the second topdressing N of upland crops. Relatively high soil N2O concentrations were observed at the transitional period from the upland crops cropping to rice planting.

  7. Effects of coal-fired thermal power plant discharges on agricultural soil and crop plants.

    PubMed

    Ajmal, M; Khan, M A

    1986-04-01

    The physicochemical properties of the upstream and downstream waters from the Upper Ganga canal, discharged cooling tower water, machine washings, and scrubber and bottom ash effluents of a 530 MW Kasimpur coal-fired thermal power plant have been determined, and their effects directly on fertile soil and indirectly on pea (Pisum sativam) and wheat (Triticum aestivum) crops have also been studied. The effluents were found to be alkaline in nature. The scrubber and bottom ash effluent was found to contain large amounts of solids and had high biochemical and chemical oxygen demands. All the effluents were found to be responsible for altering the chemical composition of the soil. The soils irrigated with the different effluents exhibited an increase in pH, organic matter, calcium carbonate, water-soluble salts, cation exchange capacity, electrical conductivity, and nitrogen and phosphorus contents while potassium content decreased, probably due to being leached to the lower layers of the soil. The effects of 100, 50, and 0% (tap water control) dilutions of cooling tower, machine washings, and scrubber and bottom ash effluents on the germination and growth of pea and wheat crops were also monitored. Using the undiluted effluents, there was 100% germination for both the crops when the irrigation was done with cooling tower effluent. The germination was restricted to 90% for the two crops when irrigated with machine washings effluent, and to 80 and 70% for pea and wheat, respectively, when irrigated with scrubber and bottom ash effluent. The samples of upstream and downstream canal water were also used for irrigating soils with and without crop plants in order to ascertain the impact of the effluents on the canal water and its subsequent effect on the crops. The soils irrigated with downstream canal water were found to contain slightly more calcium carbonate, phosphorus, and ammonia-nitrogen than those receiving upstream canal water. Though 100% germination was obtained

  8. Effect of different mulch materials on the soil dehydrogenase activity (DHA) in an organic pepper crop

    NASA Astrophysics Data System (ADS)

    Moreno, Marta M.; Peco, Jesús; Campos, Juan; Villena, Jaime; González, Sara; Moreno, Carmen

    2016-04-01

    The use biodegradable materials (biopolymers of different composition and papers) as an alternative to conventional mulches has increased considerably during the last years mainly for environmental reason. In order to assess the effect of these materials on the soil microbial activity during the season of a pepper crop organically grown in Central Spain, the soil dehydrogenase activity (DHA) was measured in laboratory. The mulch materials tested were: 1) black polyethylene (PE, 15 μm); black biopolymers (15 μm): 2) Mater-Bi® (corn starch based), 3) Sphere 4® (potato starch based), 4) Sphere 6® (potato starch based), 5) Bioflex® (polylactic acid based), 6) Ecovio® (polylactic acid based), 7) Mimgreen® (black paper, 85 g/m2). A randomized complete block design with four replications was adopted. The crop was drip irrigated following the water demand of each treatment. Soil samples (5-10 cm depth) under the different mulches were taken at different dates (at the beginning of the crop cycle and at different dates throughout the crop season). Additionally, samples of bare soil in a manual weeding and in an untreated control were taken. The results obtained show the negative effect of black PE on the DHA activity, mainly as result of the higher temperature reached under the mulch and the reduction in the gas interchange between the soil and the atmosphere. The values corresponding to the biodegradable materials were variable, although highlighting the low DHA activity observed under Bioflex®. In general, the uncovered treatments showed higher values than those reached under mulches, especially in the untreated control. Keywords: mulch, biodegradable, biopolymer, paper, dehydrogenase activity (DHA). Acknowledgements: the research was funded by Project RTA2011-00104-C04-03 from the INIA (Spanish Ministry of Economy and Competitiveness).

  9. Cumulative and residual effects of different potato cropping system management strategies on soilborne diseases and soil microbial communities over time

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Four different potato cropping systems (CS), designed to address specific management goals of soil conservation (SC), soil improvement (SI), disease suppression (DS), and a status quo standard rotation control (SQ), were evaluated for their effects on soilborne diseases of potato and soil microbial ...

  10. Soil heat flux calculation for sunlit and shaded surfaces under row crops: 1 - Model Development and sensitivity analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil heat flux at the surface (G0) is strongly influenced by whether the soil is shaded or sunlit, and therefore can have large spatial variability for incomplete vegetation cover, such as across the interrows of row crops. Most practical soil-plant-atmosphere energy balance models calculate G0 as a...

  11. Understanding the potential impact of climate change on long term soil carbon dynamics in tropical cropping systems - evidence from West Africa

    NASA Astrophysics Data System (ADS)

    Cretenet, Michel; Tittonell, Pablo; Guibert, Herve

    2010-05-01

    Long term experiments offer a unique opportunity to assess sustainability and temporal dynamics of biogeochemical cycles in agriculture, as well as the gradual impact on these of relatively slow processes such as climate change. Two long term experiments on annual cropping systems representing locally common crop rotations and cultural practices were established on two contrasting agroecological zones in Ivory Coast (in 1971) and in Mali (in 1965). These experiments were designed to assess the long-term productivity of these systems under different organic matter and nutrient management regimes, applying organic and mineral soil amendments alone or in combination. Organic soil amendments - such as animal manure, compost or plant material collected from the surroundings - were included in the experiments with the double purpose of adding nutrients for immediate crop production and adding organic matter inputs to the soil to restore (or maintain) its organic C content. Here, we provide an overview of the major trends in crop productivity and soil organic C observed in these experiments that illustrates the potential impact of climate change on the effectiveness of different measures to sustain agricultural productivity. Materials and methods Both experiments compared crop productivity on control plots without any soil amendment versus plots receiving organic matter, mineral fertilisers or both combined. The experiment at Gagnoa (southern Ivory Coast) was conducted during 23 years in a zone characterised by a bimodal rainfall regime (c. 1300 mm year-1) that allows two cropping seasons per year (Alfisols 15% clay). Every year maize was planted during the first rainy season. Organic matter was added as compost at a rate of 10 t ha-1 year-1, with or without application of 160 kg N ha-1 year-1 in mineral fertiliser (Chabalier, 1986). The experiment at N'Tarla (southern Mali) was conducted during 24 years in a zone of mono-modal rainfall (c. 900 mm year-1); Alfisols 5

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

    PubMed

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

    2016-02-01

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

  13. Anaerobic Soil Disinfestation (ASD) Combined with Soil Solarization for Root-Knot Nematode Control in Vegetable and Ornamental Crops in Florida

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anaerobic soil disinfestation (ASD) combined with soil solarization continues to be evaluated for management of plant-parasitic nematodes in vegetable and ornamental crops in Florida. ASD combines organic amendments and soil saturation to stimulate microbial activity and create anaerobic conditions...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  15. The drought of 2012: Effects on photosynthesis and soil respiration in bioenergy cropping systems of the Midwest USA

    NASA Astrophysics Data System (ADS)

    Cruse, M.; Kucharik, C. J.

    2012-12-01

    Climate change is predicted to increase the frequency and severity of drought conditions across the central US. This heightened risk on producers and economies alike also supports the need to improve our understanding of how extreme environmental conditions impact other ecosystem services such as carbon sequestration, which is directly linked to net ecosystem exchange (NEE). In doing so, the scientific community aims to improve the realism of ecosystem models that are relied upon to project changes in large scale and long-term land surface-atmosphere carbon exchange as they are affected by continued land management change and climate change. One such large-scale land management change of the next several decades in the Midwest US could be the expansion of bioenergy cropping systems across the landscape. A wide range of bioenergy cropping systems (e.g., miscanthus, switchgrass, diverse prairie, hybrid poplar) are now targeted to support a feedstock supply chain for production of cellulosic biofuels. Many of these agroecosystems have only recently begun to appear as functional types in dynamic ecosystem models, and a general lack of observational data across a wide range of soils and climate has hampered model development and validation. In response to this shortcoming, from 2009 through 2012, component measurements of ecosystem carbon exchange (total soil respiration and leaf level photosynthetic rates) have been made along with measurements of other soil and meteorological variables in three model bioenergy cropping systems (continuous corn, hybrid poplar and switchgrass) at the Great Lakes Bioenergy Research Center (GLBRC) field trial at Arlington, Wisconsin. The three cropping systems encompass a wide range of growth (e.g. C3 vs. C4, annual vs. perennial) and management (e.g., tillage, harvesting) strategies that are predicted to impart different controls on NEE given likely varying biological responses to extreme weather events. Throughout the study period, the

  16. Estimation of available water capacity components of two-layered soils using crop model inversion: Effect of crop type and water regime

    NASA Astrophysics Data System (ADS)

    Sreelash, K.; Buis, Samuel; Sekhar, M.; Ruiz, Laurent; Kumar Tomer, Sat; Guérif, Martine

    2017-03-01

    Characterization of the soil water reservoir is critical for understanding the interactions between crops and their environment and the impacts of land use and environmental changes on the hydrology of agricultural catchments especially in tropical context. Recent studies have shown that inversion of crop models is a powerful tool for retrieving information on root zone properties. Increasing availability of remotely sensed soil and vegetation observations makes it well suited for large scale applications. The potential of this methodology has however never been properly evaluated on extensive experimental datasets and previous studies suggested that the quality of estimation of soil hydraulic properties may vary depending on agro-environmental situations. The objective of this study was to evaluate this approach on an extensive field experiment. The dataset covered four crops (sunflower, sorghum, turmeric, maize) grown on different soils and several years in South India. The components of AWC (available water capacity) namely soil water content at field capacity and wilting point, and soil depth of two-layered soils were estimated by inversion of the crop model STICS with the GLUE (generalized likelihood uncertainty estimation) approach using observations of surface soil moisture (SSM; typically from 0 to 10 cm deep) and leaf area index (LAI), which are attainable from radar remote sensing in tropical regions with frequent cloudy conditions. The results showed that the quality of parameter estimation largely depends on the hydric regime and its interaction with crop type. A mean relative absolute error of 5% for field capacity of surface layer, 10% for field capacity of root zone, 15% for wilting point of surface layer and root zone, and 20% for soil depth can be obtained in favorable conditions. A few observations of SSM (during wet and dry soil moisture periods) and LAI (within water stress periods) were sufficient to significantly improve the estimation of AWC

  17. Anaerobic digestate from biogas production as a resource for improving soil fertility: effects on crop yield and soil properties

    NASA Astrophysics Data System (ADS)

    Pastorelli, Roberta; Lagomarsino, Alessandra; Vignozzi, Nadia; Valboa, Giuseppe; Papini, Rossella; Fabiani, Arturo; Simoncini, Stefania; Mocali, Stefano; Piccolo, Raimondo

    2013-04-01

    Soil fertility is fundamental in determining crops productivity in all farming systems. Production of biogas through anaerobic digestion of energy crops generates residues that can represent a valuable resource to sustain and improve soil fertility and to increase soil organic matter content. Residues from anaerobic digestion contain organic fractions and available nutrients, that can thus be returned to the cultivation soil as fertilizer and soil conditioner. However, some unknown aspects of digested residues utilization remain to explore: i) the nutrient supply and the real potential for mineral fertilization substitution, ii) the impact on the structure and functioning of soil microbial communities, iii) the direct and indirect effects on soil structure, organic matter and C mineralization. The aim of the present research was to gain a better understanding of these aspects, evaluating the effects of anaerobic digestate application on soil properties and maize yield. With the main focus of comparing mineral fertilization (250 Kg N ha-1) with digested residues addition (at the dose of 25 % and 50 % of mineral fertilizer), a triplicate sets of plots were designed in a field experiment on a silty-clay loam soil in the southern Po Valley (Italy). The amount of applied residues was calculated according to its N content in order to fertilizer each plots with the same amount of total nitrogen. Residues from digestion showed a N content of 0.4 % (60 % as N-NH4) and a C/N ratio of 3. Changes in soil quality after residues application were studied with a holistic approach, involving microbiological, physical and chemical aspects of soil fertility. In particular, we determined: the abundance and diversity of bacterial and fungal soil communities; the soil organic matter content, its distribution within soil aggregates and the C mineralization potential; cation exchange capacity; the main macro and micro nutrients; bulk density; aggregate stability. No significant

  18. Managing soil microbial communities in grain production systems through cropping practices

    NASA Astrophysics Data System (ADS)

    Gupta, Vadakattu

    2013-04-01

    Cropping practices can significantly influence the composition and activity of soil microbial communities with consequences to plant growth and production. Plant type can affect functional capacity of different groups of biota in the soil surrounding their roots, rhizosphere, influencing plant nutrition, beneficial symbioses, pests and diseases and overall plant health and crop production. The interaction between different players in the rhizosphere is due to the plethora of carbon and nutritional compounds, root-specific chemical signals and growth regulators that originate from the plant and are modulated by the physico-chemical properties of soils. A number of plant and environmental factors and management practices can influence the quantity and quality of rhizodeposition and in turn affect the composition of rhizosphere biota communities, microbe-fauna interactions and biological processes. Some of the examples of rhizosphere interactions that are currently considered important are: proliferation of plant and variety specific genera or groups of microbiota, induction of genes involved in symbiosis and virulence, promoter activity in biocontrol agents and genes correlated with root adhesion and border cell quality and quantity. The observation of variety-based differences in rhizodeposition and associated changes in rhizosphere microbial diversity and function suggests the possibility for the development of varieties with specific root-microbe interactions targeted for soil type and environment i.e. designer rhizospheres. Spatial location of microorganisms in the heterogeneous field soil matrix can have significant impacts on biological processes. Therefore, for rhizosphere research to be effective in variable seasonal climate and soil conditions, it must be evaluated in the field and within a farming systems context. With the current focus on security of food to feed the growing global populations through sustainable agricultural production systems there is a

  19. Cadmium and lead uptake by edible crops grown in a silt loam soil

    SciTech Connect

    Nwosu, J.U.; Linder, G.; Harding, A.K.

    1995-04-01

    There is increasing public concern about health effects resulting from ingestion of food containing toxic metals such as Cd and Pb. For example, a wide range of metabolic disorders and neuropsychological deficits in children have been noted, and chronic exposure to Cd has been linked to kidney failure and bone disease. The potential harm posed by the uptake of heavy metals such as Cd and Pb by plants is dependent on their abundance, mobility and bioaccumulation. Plant uptake of heavy metals was also influenced by soil pH. There is a linear relationship between soil concentrations of heavy metal and concentrations in vegetation around a zinc-lead tailing pond. The ability of the soil to retain metals depends on several factors; pH, cation exchange capacity (CEC), organic matter content, and their specific geochemical properties. Overall, the metal burden of a crop depends on: (a) uptake via the root system; (b) direct foliar uptake and translocation within the plant; and (c) surface deposition of particulate matter. Numerous studies have been conducted with agronomic crops regarding heavy metals in soils and plant uptake from sewage sludge, but only a few studies have dealt with the uptake of heavy metal mixtures in vegetables. This paper reports on germination/emergence, biomass and uptake of Cd and Pb in lettuce and radish grown in a loam soil spiked with known mixtures of CdCl{sub 2} and Pb(NO{sub 3}){sub 2}. Lettuce and radish have been used in this study because they are among the two groups of vegetable crops (leafy and root) consumed by humans. Also, earlier studies have reported that lettuce and radish bioaccumulate Cd and Pb from heavy metal polluted soils. 38 refs., 7 tabs.

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

    PubMed

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

    2015-08-01

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

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

    PubMed

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

    2015-01-01

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

  2. The effects of manure and nitrogen fertilizer applications on soil organic carbon and nitrogen in a high-input cropping system.

    PubMed

    Ren, Tao; Wang, Jingguo; Chen, Qing; Zhang, Fusuo; Lu, Shuchang

    2014-01-01

    With the goal of improving N fertilizer management to maximize soil organic carbon (SOC) storage and minimize N losses in high-intensity cropping system, a 6-years greenhouse vegetable experiment was conducted from 2004 to 2010 in Shouguang, northern China. Treatment tested the effects of organic manure and N fertilizer on SOC, total N (TN) pool and annual apparent N losses. The results demonstrated that SOC and TN concentrations in the 0-10cm soil layer decreased significantly without organic manure and mineral N applications, primarily because of the decomposition of stable C. Increasing C inputs through wheat straw and chicken manure incorporation couldn't increase SOC pools over the 4 year duration of the experiment. In contrast to the organic manure treatment, the SOC and TN pools were not increased with the combination of organic manure and N fertilizer. However, the soil labile carbon fractions increased significantly when both chicken manure and N fertilizer were applied together. Additionally, lower optimized N fertilizer inputs did not decrease SOC and TN accumulation compared with conventional N applications. Despite the annual apparent N losses for the optimized N treatment were significantly lower than that for the conventional N treatment, the unchanged SOC over the past 6 years might limit N storage in the soil and more surplus N were lost to the environment. Consequently, optimized N fertilizer inputs according to root-zone N management did not influence the accumulation of SOC and TN in soil; but beneficial in reducing apparent N losses. N fertilizer management in a greenhouse cropping system should not only identify how to reduce N fertilizer input but should also be more attentive to improving soil fertility with better management of organic manure.

  3. Mapping soils, crops, and rangelands by machine analysis of multitemporal ERTS-1 data. [Kansas and Texas

    NASA Technical Reports Server (NTRS)

    Baumgardner, M. F.; Henderson, J. A., Jr.

    1974-01-01

    ERTS-1 data, obtained during the period 25 August 1972 to 5 September 1973 over a range of test sites in the Central United States, have been used for identifying and mapping differences in soil patterns, species and conditions of cultivated crops, and conditions of rangelands. Multispectral scanner data from multiple ERTS passes over certain test sites have provided the opportunity to study temporal changes in the scene. Multispectral classifications delineating soils boundaries in different test sites compared well with existing soil association maps prepared by conventional means. Spectral analysis of ERTS data was used to identify, maps, and make areal measurements of wheat in western Kansas. Multispectral analysis of ERTS-1 data provided patterns in rangelands which can be related to soils differences, range management practices, and the extent of infestation of grasslands by mesquite (prosopis fuliflora) and juniper (juniperus spp.).

  4. Effects of glyphosate-resistant crop cultivation on soil and water quality.

    PubMed

    Cerdeira, Antonio L; Duke, Stephen O

    2010-01-01

    Transgenic glyphosate-resistant crops (GRCs) have been commercialized and grown extensively in the Western Hemisphere and, to a lesser extent, elsewhere. GRCs have generally become dominant in those countries where they have been approved for growing. Potential effects of glyphosate on soil and water are minimal, compared the effects of the herbicides that are replaced when GRCs are adopted. Perhaps the most important indirect effect is that GRCs crops promote the adoption of reduced- or no-tillage agriculture, resulting in a significant reduction in soil erosion and water contamination. Glyphosate and its degradation product, aminomethylphosphonate (AMPA), residues are not usually detected in high levels in ground or surface water in areas where glyphosate is used extensively.  Furthermore, both glyphosate and AMPA are considered to be much more toxicologically and environmentally benign than most of the herbicides replaced by glyphosate.

  5. Heavy metals in agricultural soils and crops and their health risks in Swat District, northern Pakistan.

    PubMed

    Khan, Kifayatullah; Lu, Yonglong; Khan, Hizbullah; Ishtiaq, Muhammad; Khan, Sardar; Waqas, Muhammad; Wei, Luo; Wang, Tieyu

    2013-08-01

    This study assessed the concentrations of heavy metals such as cadmium (Cd), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni) and zinc (Zn) in agricultural soils and crops (fruits, grains and vegetable) and their possible human health risk in Swat District, northern Pakistan. Cd concentration was found higher than the limit (0.05 mg/kg) set by world health organization in 95% fruit and 100% vegetable samples. Moreover, the concentrations of Cr, Cu, Mn, Ni and Zn in the soils were shown significant correlations with those in the crops. The metal transfer factor (MTF) was found highest for Cd followed by Cr>Ni>Zn>Cu>Mn, while the health risk assessment revealed that there was no health risk for most of the heavy metals except Cd, which showed a high level of health risk index (HRI⩾10E-1) that would pose a potential health risk to the consumers.

  6. Procedures for the description of agricultural crops and soils in optical and microwave remote sensing studies

    NASA Technical Reports Server (NTRS)

    Cihlar, J.; Dobson, M. C.; Schmugge, T.; Hoogeboom, P.; Janse, A. R. P.

    1987-01-01

    This paper describes procedures for characterizing agricultural crops and soils in remote sensing studies. The procedures are based on the accumulated experience of a number of researchers active in this field. Therefore, they represent a compromise between the theoretically desirable and the practically feasible, and should thus be an effective aid in further studies of this type. Although the guidelines were prepared specifically for microwave studies, adjustments were made to render the procedures applicable to optical studies as well. Given the increasing number of research teams involved in remote sensing applied to agriculture, there is an opportunity to acquire a broad data base on soils and crops in various geographic regions. To allow intercomparisons of such data, they must be obtained in a consistent manner. By following the proposed procedures and reporting results using the parameters described here, such intercomparisons should be possible on a continental or a global scale.

  7. Greenhouse gases emission from soils under major crops in Northwest India.

    PubMed

    Jain, N; Arora, P; Tomer, R; Mishra, Shashi Vind; Bhatia, A; Pathak, H; Chakraborty, D; Kumar, Vinod; Dubey, D S; Harit, R C; Singh, J P

    2016-01-15

    Quantification of greenhouse gases (GHGs) emissions from agriculture is necessary to prepare the national inventories and to develop the mitigation strategies. Field experiments were conducted during 2008-2010 at the experimental farm of the Indian Agricultural Research Institute, New Delhi, India to quantify nitrous oxide (N2O), methane (CH4), and carbon dioxide (CO2) emissions from soils under cereals, pulses, millets, and oilseed crops. Total cumulative N2O emissions were significantly different (P>0.05) among the crop types. Emission of N2O as percentage of applied N was the highest in pulses (0.67%) followed by oilseeds (0.55%), millets (0.43%) and cereals (0.40%). The emission increased with increasing rate of N application (r(2)=0.74, P<0.05). The cumulative flux of CH4 from the rice crop was 28.64±4.40 kg ha(-1), while the mean seasonal integrated flux of CO2 from soils ranged from 3058±236 to 3616±157 kg CO2 ha(-1) under different crops. The global warming potential (GWP) of crops varied between 3053 kg CO2 eq. ha(-1) (pigeon pea) and 3968 kg CO2 eq. ha(-1) (wheat). The carbon equivalent emission (CEE) was least in pigeon pea (833 kg C ha(-1)) and largest in wheat (1042 kg C ha(-1)). The GWP per unit of economic yield was the highest in pulses and the lowest in cereal crops. The uncertainties in emission values varied from 4.6 to 22.0%. These emission values will be useful in updating the GHGs emission inventory of Indian agriculture.

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

    PubMed

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

    2015-09-01

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

  9. Modeling the impact of conservation agriculture on crop production and soil properties in Mediterranean climate

    NASA Astrophysics Data System (ADS)

    Moussadek, Rachid; Mrabet, Rachid; Dahan, Rachid; Laghrour, Malika; Lembiad, Ibtissam; ElMourid, Mohamed

    2015-04-01

    In Morocco, rainfed agriculture is practiced in the majority of agricultural land. However, the intensive land use coupled to the irregular rainfall constitutes a serious threat that affect country's food security. Conservation agriculture (CA) represents a promising alternative to produce more and sustainably. In fact, the direct seeding showed high yield in arid regions of Morocco but its extending to other more humid agro-ecological zones (rainfall > 350mm) remains scarce. In order to promote CA in Morocco, differents trials have been installed in central plateau of Morocco, to compare CA to conventional tillage (CT). The yields of the main practiced crops (wheat, lentil and checkpea) under CA and CT were analyzed and compared in the 3 soils types (Vertisol, Cambisol and Calcisol). Also, we studied the effect of CA on soil organic matter (SOM) and soil losses (SL) in the 3 different sites. The APSIM model was used to model the long term impact of CA compared to CT. The results obtained in this research have shown favorable effects of CA on crop production, SOM and soil erosion. Key words: Conservation agriculture, yield, soil properties, modeling, APSIM, Morocco.

  10. Soil respiration, labile carbon pools, and enzyme activities as affected by tillage practices in a tropical rice-maize-cowpea cropping system.

    PubMed

    Neogi, S; Bhattacharyya, P; Roy, K S; Panda, B B; Nayak, A K; Rao, K S; Manna, M C

    2014-07-01

    In order to identify the viable option of tillage practices in rice-maize-cowpea cropping system that could cut down soil carbon dioxide (CO2) emission, sustain grain yield, and maintain better soil quality in tropical low land rice ecology soil respiration in terms of CO2 emission, labile carbon (C) pools, water-stable aggregate C fractions, and enzymatic activities were investigated in a sandy clay loam soil. Soil respiration is the major pathway of gaseous C efflux from terrestrial systems and acts as an important index of ecosystem functioning. The CO2-C emissions were quantified in between plants and rows throughout the year in rice-maize-cowpea cropping sequence both under conventional tillage (CT) and minimum tillage (MT) practices along with soil moisture and temperature. The CO2-C emissions, as a whole, were 24 % higher in between plants than in rows, and were in the range of 23.4-78.1, 37.1-128.1, and 28.6-101.2 mg m(-2) h(-1) under CT and 10.7-60.3, 17.3-99.1, and 17.2-79.1 mg m(-2) h(-1) under MT in rice, maize, and cowpea, respectively. The CO2-C emission was found highest under maize (44 %) followed by rice (33 %) and cowpea (23 %) irrespective of CT and MT practices. In CT system, the CO2-C emission increased significantly by 37.1 % with respect to MT on cumulative annual basis including fallow. The CO2-C emission per unit yield was at par in rice and cowpea signifying the beneficial effect of MT in maintaining soil quality and reduction of CO2 emission. The microbial biomass C (MBC), readily mineralizable C (RMC), water-soluble C (WSC), and permanganate-oxidizable C (PMOC) were 19.4, 20.4, 39.5, and 15.1 % higher under MT than CT. The C contents in soil aggregate fraction were significantly higher in MT than CT. Soil enzymatic activities like, dehydrogenase, fluorescein diacetate, and β-glucosidase were significantly higher by 13.8, 15.4, and 27.4 % under MT compared to CT. The soil labile C pools, enzymatic activities, and

  11. Assimilation of Remotely Sensed Soil Moisture and Vegetation with a Crop Simulation Model

    NASA Astrophysics Data System (ADS)

    Ines, A. V. M.; Das, N. N.

    2015-12-01

    When a crop model is used to predict crop yields early in the growing season, two sources of uncertainties prevail those coming from climate and model uncertainties. Climate uncertainty is greatest early in the growing season and tends to decrease as weather data become available in the growing season. Model uncertainty due to errors in model structure, modeling assumptions and other ancillary data, generally remains constant through the growing season. Skillful climate forecasts can reduce climate uncertainty especially at the earlier stages of the growing season, while assimilating remote sensing (RS) data within the growing season can reduced model uncertainty. In this talk, we focus on the development, application and verification of a crop modeling-data assimilation framework capable of ingesting RS soil moisture and vegetation parameters, in this case, leaf area index for predicting aggregated crop yields. We discuss the lessons learned from our case studies in Iowa, with more homogenous rainfed agricultural system, and Georgia, more heterogeneous mixed rainfed/irrigated agricultural system. One of our goals is to show the utility of better soil moisture products, e.g. from SMAP, for improving the prediction of agricultural/hydrological variables with actionable lead-times.

  12. Bacterial Indicator of Agricultural Management for Soil under No-Till Crop Production

    PubMed Central

    Rosa, Silvina M.; Simonetti, Leandro; Duval, Matías E.; Galantini, Juan A.; Bedano, José C.; Wall, Luis G.; Erijman, Leonardo

    2012-01-01

    The rise in the world demand for food poses a challenge to our ability to sustain soil fertility and sustainability. The increasing use of no-till agriculture, adopted in many areas of the world as an alternative to conventional farming, may contribute to reduce the erosion of soils and the increase in the soil carbon pool. However, the advantages of no-till agriculture are jeopardized when its use is linked to the expansion of crop monoculture. The aim of this study was to survey bacterial communities to find indicators of soil quality related to contrasting agriculture management in soils under no-till farming. Four sites in production agriculture, with different soil properties, situated across a west-east transect in the most productive region in the Argentinean pampas, were taken as the basis for replication. Working definitions of Good no-till Agricultural Practices (GAP) and Poor no-till Agricultural Practices (PAP) were adopted for two distinct scenarios in terms of crop rotation, fertilization, agrochemicals use and pest control. Non-cultivated soils nearby the agricultural sites were taken as additional control treatments. Tag-encoded pyrosequencing was used to deeply sample the 16S rRNA gene from bacteria residing in soils corresponding to the three treatments at the four locations. Although bacterial communities as a whole appeared to be structured chiefly by a marked biogeographic provincialism, the distribution of a few taxa was shaped as well by environmental conditions related to agricultural management practices. A statistically supported approach was used to define candidates for management-indicator organisms, subsequently validated using quantitative PCR. We suggest that the ratio between the normalized abundance of a selected group of bacteria within the GP1 group of the phylum Acidobacteria and the genus Rubellimicrobium of the Alphaproteobacteria may serve as a potential management-indicator to discriminate between sustainable vs. non

  13. Bacterial indicator of agricultural management for soil under no-till crop production.

    PubMed

    Figuerola, Eva L M; Guerrero, Leandro D; Rosa, Silvina M; Simonetti, Leandro; Duval, Matías E; Galantini, Juan A; Bedano, José C; Wall, Luis G; Erijman, Leonardo

    2012-01-01

    The rise in the world demand for food poses a challenge to our ability to sustain soil fertility and sustainability. The increasing use of no-till agriculture, adopted in many areas of the world as an alternative to conventional farming, may contribute to reduce the erosion of soils and the increase in the soil carbon pool. However, the advantages of no-till agriculture are jeopardized when its use is linked to the expansion of crop monoculture. The aim of this study was to survey bacterial communities to find indicators of soil quality related to contrasting agriculture management in soils under no-till farming. Four sites in production agriculture, with different soil properties, situated across a west-east transect in the most productive region in the Argentinean pampas, were taken as the basis for replication. Working definitions of Good no-till Agricultural Practices (GAP) and Poor no-till Agricultural Practices (PAP) were adopted for two distinct scenarios in terms of crop rotation, fertilization, agrochemicals use and pest control. Non-cultivated soils nearby the agricultural sites were taken as additional control treatments. Tag-encoded pyrosequencing was used to deeply sample the 16S rRNA gene from bacteria residing in soils corresponding to the three treatments at the four locations. Although bacterial communities as a whole appeared to be structured chiefly by a marked biogeographic provincialism, the distribution of a few taxa was shaped as well by environmental conditions related to agricultural management practices. A statistically supported approach was used to define candidates for management-indicator organisms, subsequently validated using quantitative PCR. We suggest that the ratio between the normalized abundance of a selected group of bacteria within the GP1 group of the phylum Acidobacteria and the genus Rubellimicrobium of the Alphaproteobacteria may serve as a potential management-indicator to discriminate between sustainable vs. non

  14. How effective are soil and water conservation techniques in reducing annual plot runoff and soil loss? A pan-European and Mediterranean review and analysis.

    NASA Astrophysics Data System (ADS)

    Maetens, W.; Poesen, J.; Vanmaercke, M.

    2012-04-01

    While a substantial number of experimental studies on the effectiveness of soil and water conservation techniques (SWCTs) in reducing annual runoff (Ra) and annual soil loss (SLa) at plot scales in Europe and the Mediterranean exists, a comprehensive overview and analysis of plot Ra and SLa data is lacking. Therefore, the objective of this study is to analyse the effectiveness of SWCT in reducing Ra and SLa in Europe and the Mediterranean, as well as to explore the factors that determine SWCT effectiveness. In the framework of the FP6 project DESIRE (http://www.desire-project.eu), a comprehensive plot database was compiled based on an extensive literature review covering 101 reports and publications. The database contains Ra and SLa data measured on runoff plots, where various SWCTs were tested in the Euro-Mediterranean region. The total database contains 353 plots, corresponding to 2 093 plot-years from 103 plot measuring stations throughout Europe and the Mediterranean. For 224 of these plots (corresponding to 1 567 plot-years), Ra and/or SLa from a paired plot with the same dimensions, land use and measuring period, but without the application SWCT was available, allowing to assess the effectiveness of the applied SWCTs. Documented SWCTs include cover crops, mulching, grass buffer strips, strip cropping, exclosure, no-tillage, reduced tillage, contour tillage, deep tillage, drainage, soil amendment, terraces, contour bunds and geotextiles. Analyses of the database shows that there are clear differences in effectiveness in reducing Ra and SLa between different SWCTs. Techniques related to crop and vegetation management like mulching (median reduction of Ra to 32% and SLa to 23% of the corresponding values measured on the plot without SWCT) and cover crops (36% for Ra and 14% for SLa) are more effective than soil management techniques like no-tillage (85% for Ra and 57% for SLa) or reduced tillage (90% for Ra and 68% for SLa). While these techniques are commonly

  15. Using NASA UAVSAR Datasets to Link Soil Moisture to Crop Conditions

    NASA Astrophysics Data System (ADS)

    Davitt, A. W. D.; McDonald, K. C.; Azarderakhsh, M.; Winter, J.

    2015-12-01

    California and The Central Valley are experiencing one of that region's worst, persistent droughts, which represents the continuation of a prolonged drought that started in the early 2000's. Due to the continued drought, many agricultural regions in The Central Valley have been experiencing water shortages, negatively impacting agricultural production and the socio-economics of the region. Due to these impacts, there has been an increased incentive to find new ways to conserve water for use in irrigation. Recent advances in remote sensing techniques provide the ability for end users to better understand field conditions so they may make more informed decisions on irrigation timing and amounts. However, a good understanding of soil moisture and its role in crop health and yield is lacking to support informed water management decisions. Though known to be important, a robust understanding of the role of the spatio-temporal patterns in soil moisture linked to crop health is lacking. Remote sensing platforms such as NASA's Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) provide the capacity to obtain within-field measurements to estimate within-field and field-to-field variability in soil moisture. UAVSAR radar images acquired from 2010 to 2014 for Yolo County, California are being examined to determine the suitability of high resolution (field scale) multi-temporal L-band radar backscatter imagery for soil moisture assessment and crop conditions through the growing season. By using such data and linking to in-situ meteorology measurements, modeling (MIMICS), and other remote sensing derived datasets (Sentinel, Landsat, MODIS, and TOPS-SIMS), an integrated monitoring system can potentially support the assessment of agricultural field conditions. This allows growers to optimize the use of limited water supplies through informed water management practices, potentially improving cro