The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Lajpat R Ahuja - One of the best experts on this subject based on the ideXlab platform.
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irrigation strategies to improve the water use efficiency of wheat maize Double Cropping systems in north china plain
Agricultural Water Management, 2010Co-Authors: Quanxiao Fang, Robert W Malone, Lajpat R Ahuja, Gerrit HoogenboomAbstract:Water is the most important limiting factor of wheat (Triticum aestivum L.) and maize (Zea mays L.) Double Cropping systems in the North China Plain (NCP). A two-year experiment with four irrigation levels based on crop growth stages was used to calibrate and validate RZWQM2, a hybrid model that combines the Root Zone Water Quality Model (RZWQM) and DSSAT4.0. The calibrated model was then used to investigate various irrigation strategies for high yield and water use efficiency (WUE) using weather data from 1961 to 1999. The model simulated soil moisture, crop yield, above-ground biomass and WUE in responses to irrigation schedules well, with root mean square errors (RMSEs) of 0.029 cm(3) cm(-3), 0.59 Mg ha(-1), 2.05 Mg ha(-1), and 0.19 kg m(-3), respectively, for wheat; and 0.027 cm(3) cm(-3), 0.71 Mg ha(-1), 1.51 Mg ha(-1) and 0.35 kg m(-3), respectively, for maize. WUE increased with the amount of irrigation applied during the dry growing season of 2001-2002, but was less sensitive to irrigation during the wet season of 2002-2003. Long-term simulation using weather data from 1961 to 1999 showed that initial soil water at planting was adequate (at 82% of crop available water) for wheat establishment due to the high rainfall during the previous maize season. Preseason irrigation for wheat commonly practiced by local farmers should be postponed to the most sensitive growth stage (stem extension) for higher yield and WUE in the area. Preseason irrigation for maize is needed in 40% of the years. With limited irrigation available (100, 150, 200, or 250 mm per year), 80% of the water allocated to the critical wheat growth stages and 20% applied at maize planting achieved the highest WUE and the least water drainage overall for the two crops. Published by Elsevier B.V.
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irrigation strategies to improve the water use efficiency of wheat maize Double Cropping systems in north china plain
Agricultural Water Management, 2010Co-Authors: Quanxiao Fang, Robert W Malone, Lajpat R Ahuja, Gerrit HoogenboomAbstract:Water is the most important limiting factor of wheat (Triticum aestivum L.) and maize (Zea mays L.) Double Cropping systems in the North China Plain (NCP). A two-year experiment with four irrigation levels based on crop growth stages was used to calibrate and validate RZWQM2, a hybrid model that combines the Root Zone Water Quality Model (RZWQM) and DSSAT4.0. The calibrated model was then used to investigate various irrigation strategies for high yield and water use efficiency (WUE) using weather data from 1961 to 1999. The model simulated soil moisture, crop yield, above-ground biomass and WUE in responses to irrigation schedules well, with root mean square errors (RMSEs) of 0.029cm3cm-3, 0.59Mgha-1, 2.05Mgha-1, and 0.19kgm-3, respectively, for wheat; and 0.027cm3cm-3, 0.71Mgha-1, 1.51Mgha-1 and 0.35kgm-3, respectively, for maize. WUE increased with the amount of irrigation applied during the dry growing season of 2001-2002, but was less sensitive to irrigation during the wet season of 2002-2003. Long-term simulation using weather data from 1961 to 1999 showed that initial soil water at planting was adequate (at 82% of crop available water) for wheat establishment due to the high rainfall during the previous maize season. Preseason irrigation for wheat commonly practiced by local farmers should be postponed to the most sensitive growth stage (stem extension) for higher yield and WUE in the area. Preseason irrigation for maize is needed in 40% of the years. With limited irrigation available (100, 150, 200, or 250mm per year), 80% of the water allocated to the critical wheat growth stages and 20% applied at maize planting achieved the highest WUE and the least water drainage overall for the two crops.
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modeling nitrogen and water management effects in a wheat maize Double Cropping system
Journal of Environmental Quality, 2008Co-Authors: Quanxiao Fang, Robert W Malone, S A Saseendran, Lajpat R AhujaAbstract:Excessive N and water use in agriculture causes environmental degradation and can potentially jeopardize the sustainability of the system. A field study was conducted from 2000 to 2002 to study the effects of four N treatments (0, 100, 200, and 300 kg N ha(-1) per crop) on a wheat (Triticum aestivum L.) and maize (Z a mays L.) Double Cropping system under 70 +/- 15% field capacity in the North China Plain (NCP). The root zone water quality model (RZWQM), with the crop estimation through resource and environment synthesis (CERES) plant growth modules incorporated, was evaluated for its simulation of crop production, Soil water, and N leaching in the Double Cropping system. Soil water content, biomass, and grain yield were better simulated with normalized root mean square errors (NRMSE, RMSE divided by mean observed value) from 0.11 to 0.15 than soil NO3-N and plant N uptake that had NRMSE from 0.19 to 0.43 across these treatments. The long-term simulation with historical weather data showed that, at 200 kg N ha(-1) per crop application rate, auto-irrigation triggered at 50% of the field capacity and recharged to 60% field capacity in the 0- to 50-cm soil profile were adequate for obtaining acceptable yield levels in this intensified Double Cropping system. Results also showed potential savings of more than 30% of the current N application rates per crop from 300 to 200 kg N ha(-1), which could reduce about 60% of the N leaching without compromising crop yields.
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modeling a wheat maize Double Cropping system in china using two plant growth modules in rzwqm
Agricultural Systems, 2006Co-Authors: S A Saseendran, Timothy R Green, G N Flerchinger, Lajpat R AhujaAbstract:Agricultural system models are potential tools for evaluating soil-water-nutrient management in intensive Cropping systems. In this study, we calibrated and validated the Root Zone Water Quality Model (RZWQM) with both a generic plant growth module (RZWQM-G) and the CERES plant growth module (RZWQM-C) for simulating winter wheat (Tritictim aestivum L.) and maize (Zea mays L.) Double Cropping systems in the Northern China Plain (NCP), China. Data were obtained from an experiment conducted at Yucheng Integrated Agricultural Experimental Station (36 degrees 57'N, 11 degrees 36'E, 28 m asl) in the North China Plain (NCP) from 1997 to 2001 (eight crop seasons) with field measurements of evapotranspiration, soil water, soil temperature, leaf area index (LAI), biomass and grain yield. Using the same soil water and nutrient modules, both plant modules were calibrated using the data from one crop sequence during 1998-1999 when detailed measurements of LAI and biomass growth were available. The calibrated models were then used to simulate maize and wheat production in other years. Overall simulation runs from 1997 to 2001 showed that the RZWQM-C model simulated grain yields with a RMSE of 0.94 Mg ha(-1) in contrast to a RMSE of 1.23 Mg ha(-1) with RZWQM-G. The RMSE for biomass simulation was 2.07 Mg ha(-1) with RZWQM-G and 2.26 Mg ha(-1) with RZWQM-C model. The RMSE values of simulated evapotranspiration, soil water, soil temperature and LAI were 1.4 mm, 0.046 m(3) m(-3), 1.75 degrees C and 1.0 for RZWQM-G and 1.4 mm, 0.047 m(3) m(-3), 1.84 degrees C and 1.1 for RZWQM-C, respectively. The study revealed that both plant models were able to simulate the intensive Cropping systems once they were calibrated for the local weather and soil conditions. Sensitivity analysis also showed that a reduction of 25% of current water and N applications reduced N leaching by 24-77% with crop yield reduction of 1-9% only. (c) 2005 Elsevier Ltd. All rights reserved.
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evaluating nitrogen and water management in a Double Cropping system using rzwqm
Vadose Zone Journal, 2006Co-Authors: S A Saseendran, Timothy R Green, Lajpat R AhujaAbstract:Simulation of water and nutrient processes can enhance intensive agriculture to help feed the world9s population in a sustainable manner. Due to excessive N application, environmental protection and agricultural sustainability have become major issues in agriculture. In this study, we calibrated and tested the RZWQM model to assess N management in a Double-Cropping system comprised of winter wheat ( Triticum aestivum L.) and corn ( Zea mays L.) at Luancheng, in the North China Plain. Data, including biomass, grain yield, soil water, and soil and crop N, were used from 2001–2003 field trials applying 200 to 800 kg N ha −1 yr −1 for five Cropping seasons. In general, soil water, biomass, and grain yields were predicted better than plant N uptake or soil residual N. Once it had been tested and used to improve the understanding of N processes in this Cropping system, the model was further used to evaluate the effects of alternative water and N management scenarios on N leaching. Typical application rates of both water and N could be reduced by about half based on these results, which would have high economic, social, and environmental impacts in China. The results also demonstrate the potential of RZWQM for evaluating N and water management practices in other regions and climates of the world with intensive agriculture.
Ke Wang - One of the best experts on this subject based on the ideXlab platform.
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functional diversity of rhizosphere soil microbial communities in response to different tillage and crop residue retention in a Double Cropping rice field
PLOS ONE, 2020Co-Authors: Hai Ming Tang, Xiao Ping Xiao, Wen-guang Tang, Xiaochen Pan, Kaikai Cheng, Lihong Shi, Li Wen, Ke WangAbstract:Microbial community functional diversity is a sensitive indicator of soil quality, soil management such as tillage and crop residue which can affect the microbial community functional diversity of paddy field. However, there is still limited information about the influence of different tillage and crop residue management on rhizosphere soil microbial community functional diversity in a Double-Cropping rice (Oryza sativa L.) field. Therefore, four tillage treatments were set up in paddy field, tillage treatments were included: conventional tillage with residue incorporation (CT), rotary tillage with residue incorporation (RT), no-tillage with residue retention (NT), and rotary tillage with residue removed as control (RTO). And the effects of CT, RT, NT, and RTO treatments on the average well color development (AWCD), genetic diversity indices and carbon source utilization of rhizosphere soil were studied in the present paper. The results showed that the values of AWCD with CT, RT and NT treatments were higher than that of RTO treatment. It was implied that application of crop residue management resulted in the variation of the carbon utilization efficiency of rhizosphere soil microbial communities. At maturity stages of early and late rice, the Richness indices, Shannon indices and McIntosh indices with CT treatment were significantly higher than that of RTO treatment, and with the order as CT>RT>NT>RTO. Principal component analysis (PCA) results indicated that there were significant differences in carbon substrate utilization patterns among different tillage treatments. Carbohydrates and amino acids were the main carbon resources utilized by rhizosphere soil microbes. Therefore, the combined application of tillage with crop residue management could significantly increase the rhizosphere soil microbial community functional diversity in the Double-Cropping paddy field of southern China.
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effects of winter cover crops straws incorporation on ch4 and n2o emission from Double Cropping paddy fields in southern china
PLOS ONE, 2014Co-Authors: Hai Ming Tang, Xiao Ping Xiao, Weiyan Li, Wen-guang Tang, Ke Wang, Guang-li YangAbstract:Residue management in Cropping systems is believed to improve soil quality. However, the effects of residue management on methane (CH4) and nitrous oxide (N2O) emissions from paddy field in Southern China have not been well researched. The emissions of CH4 and N2O were investigated in Double Cropping rice (Oryza sativa L.) systems with straw returning of different winter cover crops by using the static chamber-gas chromatography technique. A randomized block experiment with three replications was established in 2004 in Hunan Province, China, including rice–rice–ryegrass (Lolium multiflorum L.) (Ry-R-R), rice–rice–Chinese milk vetch (Astragalus sinicus L.) (Mv-R-R) and rice–rice with winter fallow (Fa-R-R). The results showed that straw returning of winter crops significantly increased the CH4 emission during both rice growing seasons when compared with Fa-R-R. Ry-R-R plots had the largest CH4 emissions during the early rice growing season with 14.235 and 15.906 g m−2 in 2012 and 2013, respectively, when Ry-R-R plots had the largest CH4 emission during the later rice growing season with 35.673 and 38.606 g m−2 in 2012 and 2013, respectively. The Ry-R-R and Mv-R-R also had larger N2O emissions than Fa-R-R in both rice seasons. When compared to Fa-R-R, total N2O emissions in the early rice growing season were increased by 0.05 g m−2 in Ry-R-R and 0.063 g m−2 in Mv-R-R in 2012, and by 0.058 g m−2 in Ry-R-R and 0.068 g m−2 in Mv-R-R in 2013, respectively. Similar result were obtained in the late rice growing season, and the total N2O emissions were increased by 0.104 g m−2 in Ry-R-R and 0.073 g m−2 in Mv-R-R in 2012, and by 0.108 g m−2 in Ry-R-R and 0.076 g m−2 in Mv-R-R in 2013, respectively. The global warming potentials (GWPs) from paddy fields were ranked as Ry-R-R>Mv-R-R>Fa-R-R. As a result, straw returning of winter cover crops has significant effects on increase of CH4 and N2O emission from paddy field in Double Cropping rice system.
Hai Ming Tang - One of the best experts on this subject based on the ideXlab platform.
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functional diversity of rhizosphere soil microbial communities in response to different tillage and crop residue retention in a Double Cropping rice field
PLOS ONE, 2020Co-Authors: Hai Ming Tang, Xiao Ping Xiao, Wen-guang Tang, Xiaochen Pan, Kaikai Cheng, Lihong Shi, Li Wen, Ke WangAbstract:Microbial community functional diversity is a sensitive indicator of soil quality, soil management such as tillage and crop residue which can affect the microbial community functional diversity of paddy field. However, there is still limited information about the influence of different tillage and crop residue management on rhizosphere soil microbial community functional diversity in a Double-Cropping rice (Oryza sativa L.) field. Therefore, four tillage treatments were set up in paddy field, tillage treatments were included: conventional tillage with residue incorporation (CT), rotary tillage with residue incorporation (RT), no-tillage with residue retention (NT), and rotary tillage with residue removed as control (RTO). And the effects of CT, RT, NT, and RTO treatments on the average well color development (AWCD), genetic diversity indices and carbon source utilization of rhizosphere soil were studied in the present paper. The results showed that the values of AWCD with CT, RT and NT treatments were higher than that of RTO treatment. It was implied that application of crop residue management resulted in the variation of the carbon utilization efficiency of rhizosphere soil microbial communities. At maturity stages of early and late rice, the Richness indices, Shannon indices and McIntosh indices with CT treatment were significantly higher than that of RTO treatment, and with the order as CT>RT>NT>RTO. Principal component analysis (PCA) results indicated that there were significant differences in carbon substrate utilization patterns among different tillage treatments. Carbohydrates and amino acids were the main carbon resources utilized by rhizosphere soil microbes. Therefore, the combined application of tillage with crop residue management could significantly increase the rhizosphere soil microbial community functional diversity in the Double-Cropping paddy field of southern China.
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effects of winter cover crops straws incorporation on ch4 and n2o emission from Double Cropping paddy fields in southern china
PLOS ONE, 2014Co-Authors: Hai Ming Tang, Xiao Ping Xiao, Weiyan Li, Wen-guang Tang, Ke Wang, Guang-li YangAbstract:Residue management in Cropping systems is believed to improve soil quality. However, the effects of residue management on methane (CH4) and nitrous oxide (N2O) emissions from paddy field in Southern China have not been well researched. The emissions of CH4 and N2O were investigated in Double Cropping rice (Oryza sativa L.) systems with straw returning of different winter cover crops by using the static chamber-gas chromatography technique. A randomized block experiment with three replications was established in 2004 in Hunan Province, China, including rice–rice–ryegrass (Lolium multiflorum L.) (Ry-R-R), rice–rice–Chinese milk vetch (Astragalus sinicus L.) (Mv-R-R) and rice–rice with winter fallow (Fa-R-R). The results showed that straw returning of winter crops significantly increased the CH4 emission during both rice growing seasons when compared with Fa-R-R. Ry-R-R plots had the largest CH4 emissions during the early rice growing season with 14.235 and 15.906 g m−2 in 2012 and 2013, respectively, when Ry-R-R plots had the largest CH4 emission during the later rice growing season with 35.673 and 38.606 g m−2 in 2012 and 2013, respectively. The Ry-R-R and Mv-R-R also had larger N2O emissions than Fa-R-R in both rice seasons. When compared to Fa-R-R, total N2O emissions in the early rice growing season were increased by 0.05 g m−2 in Ry-R-R and 0.063 g m−2 in Mv-R-R in 2012, and by 0.058 g m−2 in Ry-R-R and 0.068 g m−2 in Mv-R-R in 2013, respectively. Similar result were obtained in the late rice growing season, and the total N2O emissions were increased by 0.104 g m−2 in Ry-R-R and 0.073 g m−2 in Mv-R-R in 2012, and by 0.108 g m−2 in Ry-R-R and 0.076 g m−2 in Mv-R-R in 2013, respectively. The global warming potentials (GWPs) from paddy fields were ranked as Ry-R-R>Mv-R-R>Fa-R-R. As a result, straw returning of winter cover crops has significant effects on increase of CH4 and N2O emission from paddy field in Double Cropping rice system.
Yuming Zhang - One of the best experts on this subject based on the ideXlab platform.
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yield scaled n2o emissions in a winter wheat summer corn Double Cropping system
Atmospheric Environment, 2012Co-Authors: Shuping Qin, O Oenema, Yuying Wang, Yuming Zhang, Wenxu DongAbstract:Abstract Emissions of nitrous oxide (N2O) from agricultural soils contribute to global warming and stratospheric ozone depletion. Applications of fertilizer nitrogen (N) increase N2O emission, but also increase agricultural production. Here, we report on the responses of crop yield, N2O emission and yield-scaled N2O emission (N2O emission per unit N uptake by grain and aboveground biomass) to different N fertilizer rates in a winter wheat–summer corn Double-Cropping system in the North China Plain. Soil N2O emission measurements were carried out for two years in a long-term field experiment, under semi-arid conditions with four flood irrigations events per year. Our results indicated that N2O emissions were linear functions and yield-scaled N2O emissions were cubic functions of N fertilizer application rate. Yield-scaled N2O emissions were lowest at application rates of 136 kg N ha−1 yr−1. Using a quadratic-plateau model, it was found that maximal crop yields were achieved at an application rate of 317 kg N ha−1 yr−1, which is 20% less than current practice. This level is suggested to be a compromise between achieving food security and mitigation N2O emissions.
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tillage and residue management effects on soil carbon and co2 emission in a wheat corn Double Cropping system
Nutrient Cycling in Agroecosystems, 2009Co-Authors: Wenxu Dong, Suying Che, Yuming ZhangAbstract:The mitigation of CO2 emission into the atmosphere is important and any information on how to implement adjustments to agricultural practices and improve soil organic matter (SOM) stock would be helpful. We studied the effect of tillage and residue management on soil carbon sequestration and CO2 emissions in loam soil cropped in a winter wheat–corn rotation in northern China. There were five treatments: mouldboard ploughing, rotary tillage and no-tillage with chopped residues (MC, RC and NC), additional no-tillage with whole residue (NW) and mouldboard ploughing without residue (CK). After 5 years of each tillage system, MC and RC had higher annual CO2 efflux from soil. The CO2 effluxes were correlated with the ratio of dissolved organic carbon to soil microbial biomass (DOC/MBC) among treatments. This effect may be due to less immobilization of soil carbon by microorganisms under long-time intensive tillage. Although both MBC and DOC showed seasonal variability, when averaged across the sampling period only MBC discriminated between treatments. After 5 years of tillage, all treatments except CK increased SOM (0.16–0.99 Mg C ha−1 year−1) at 0–30 cm depth and NC was the greatest, resulting from historical SOM depletion and large C return from recent residues. Despite the lowest CO2 flux being from the NW treatment, lower input residue from decreased biomass may have lowered C sequestration. To improve soil C sequestration in rotations, the input of residue and the CO2 emission should be balanced by adopting appropriate tillage and residue management.
Yang Guangli - One of the best experts on this subject based on the ideXlab platform.
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effects of winter cover crops residue returning on soil enzyme activities and soil microbial community in Double Cropping rice fields
PLOS ONE, 2014Co-Authors: Tang Haiming, Xiao Xiaoping, Tang Wenguang, Lin Yechun, Wang Ke, Yang GuangliAbstract:Residue management in Cropping systems is useful to improve soil quality. However, the studies on the effects of residue management on the enzyme activities and microbial community of soils in South China are few. Therefore, the effects of incorporating winter cover crop residue with a Double-Cropping rice (Oryza sativa L.) system on soil enzyme activities and microbial community in Southern China fields were studied. The experiment has conducted at the experimental station of the Institute of Soil and Fertilizer Research, Hunan Academy of Agricultural Science, China since winter 2004. Four winter Cropping systems were used: rice–rice–ryegrass (Lolium multiflorum L.) (R-R-Ry), rice–rice–Chinese milk vetch (Astragalus sinicus L.) (R-R-Mv), rice–rice–rape (Brassica napus L.) (R-R-Ra) and rice–rice with winter fallow (R-R-Fa). The result indicated that the enzyme activities in the R-R-Ry, R-R-Mv and R-R-Ra systems were significantly higher (P<0.05) than in the R-R-Fa system during the early and late rice season. The β-glucosidase activities reached peak values at the tillering stage after residue application, and alkaline phosphatase activities reached peak values at the booting stage after residue application, respectively, the activities of β-glucosidase and alkaline phosphatase gradually decreased after this. Arylsulfatase activities reached peak values at the maturity stage. Arylamidase activities reached peak values at the maturity stage. The numbers of aerobic bacteria, actinomycete and fungus of residue treatments were significantly higher (P<0.05) than that the R-R-Ra system. However, the number of anaerobic bacteria under the R-R-Ry and R-R-Mv systems was significantly lower (P<0.05) than that under the R-R-Fa system during early rice and late rice growth stage. Thus, incorporation of winter cover crops into rotations may increase enzyme activities and microbial community in soil and therefore improve soil quality.