为探究土壤-作物系统水热碳氮耦合模型(Soil Water Heat Carbon and Nitrogen Simulation,WHCNS)在华北平原的适用性,本研究基于2年的夏玉米田间试验数据对WHCNS模型进行率定和验证。结果显示,经率定后的WHCNS模型可用于土壤水力特性、...为探究土壤-作物系统水热碳氮耦合模型(Soil Water Heat Carbon and Nitrogen Simulation,WHCNS)在华北平原的适用性,本研究基于2年的夏玉米田间试验数据对WHCNS模型进行率定和验证。结果显示,经率定后的WHCNS模型可用于土壤水力特性、氮损失和作物生长发育的模拟。表明WHCNS模型具有精确模拟华北平原夏玉米生育期内土壤水力运动特性、氮损失和作物生长的能力。展开更多
Selecting an appropriate planting density is an effective way to improve crop water productivity(WPC).However, there is a lack of research on the balance between evapotranspiration(ET) partitioning, water consumption,...Selecting an appropriate planting density is an effective way to improve crop water productivity(WPC).However, there is a lack of research on the balance between evapotranspiration(ET) partitioning, water consumption, and grain production under different summer maize planting densities. To close this knowledge gap, a two-year field experiment was conducted in the North China Plain(NCP) to reveal the effects of different planting densities(HD: 100,000 plants ha^(-1);MD: 78,000 plants ha^(-1);LD:56,000 plants ha^(-1)) on ET partitioning, grain yield, and water productivity of summer maize. The water-heat-carbon-nitrogen simulator(WHCNS) model was employed to calculate ET partitioning and perform scenario simulation after calibration and validation. The results showed that compared to the LD treatment, ET of the summer maize and grain yield in the MD and HD treatments significantly increased. Model simulations showed that the ratio of evaporation to ET ranged from 25.6% to 30.7%and reduced as increasing planting densities. Increasing planting density enhanced total transpiration of summer maize more than 20 mm, comparing to LD treatment, and the most significant differences between various planting densities appeared at the mid-growth stage(August 1 to 31). Scenario simulations indicated that grain yield and WPCof summer maize were consistently higher in wet and normal years compared to drought years, exhibiting a trend of initially increasing and then decreasing with increasing planting density. The highest grain yield and WPCof summer maize were observed at a planting density of approximately 80,000 plants ha^(-1). The results provide theoretical support for selecting a summer maize planting density and effectively utilizing agricultural water in the NCP.展开更多
The eutrophication of rivers and lakes is becoming increasingly common,primarily because of pollution from agricultural non-point sources.We investigated the effects of optimized water and fertilizer treatments on agr...The eutrophication of rivers and lakes is becoming increasingly common,primarily because of pollution from agricultural non-point sources.We investigated the effects of optimized water and fertilizer treatments on agricultural non-point source pollution in the Nansi Lake basin.The water heat carbon nitrogen simulator model(WHCNS model)was used to analyze water and nitrogen transport in wheat fields in Nansi Lake basin.Four water and fertilizer treatments were set up:conventional fertilization and irrigation(CK),reduced controlled-release fertilizer and conventional irrigation(F2W1),an equal amount of controlled-release fertilizer and reduced irrigation(F1W2),and reduced controlled-release fertilizer and reduced irrigation(F2W2).The results indicated that the replacement of conventional fertilizers with controlled-release fertilizers,combined with reduced irrigation,led to reduced nitrogen loss.Compared with those of the CK,the cumulative nitrogen leaching and ammonia volatilization of F2W1 were reduced by 8.90 and 41.67%,respectively;under F1W2,the same parameters were reduced by 12.50 and 15.99%,respectively.Compared with the other treatments,F2W2 significantly reduced nitrogen loss while producing a stable yield.Compared with those of the CK,ammonia volatilization and nitrogen loss due to leaching were reduced by 29.17 and 27.13%,respectively,water and nitrogen use efficiencies increased by 11.38 and 17.80%,respectively.F2W2 showed the best performance among the treatments,considering water and fertilizer management.Our findings highlight the effectiveness of optimizing water and fertilizer application in improving the water and nitrogen use efficiency of wheat,which is of great significance for mitigating nitrogen loss from farmland in the Nansi Lake basin.展开更多
定量描述农田生态系统中土壤水分动态、碳氮循环过程和作物生长发育规律,对水氮资源高效利用、作物生产决策和环境保护具有十分重要的意义。该文在总结前人研究成果的基础上,引用了联合国粮食及农业组织的气象模块、荷兰的PS123作物模...定量描述农田生态系统中土壤水分动态、碳氮循环过程和作物生长发育规律,对水氮资源高效利用、作物生产决策和环境保护具有十分重要的意义。该文在总结前人研究成果的基础上,引用了联合国粮食及农业组织的气象模块、荷兰的PS123作物模型和丹麦的Daisy模型的碳氮循环模块;借鉴了RZWQM和Hydrus-1D的水分溶质运移模块的相关理论,并在其基础上进行了修改与完善,构建了土壤-作物-大气系统水热碳氮耦合模拟模型WHCNS（soil water heat carbon and nitrogen simulation）。该模型以天为步长,考虑了气象条件、作物生物学特性和田间管理驱动。土壤水分入渗和再分布过程分别采用Green-Ampt模型和Richards方程来描述。土壤氮素运移使用对流-弥散方程来描述,源汇项中考虑碳氮循环的各个过程（有机质矿化、生物固持、尿素水解、氨挥发、硝化、反硝化和作物吸收等）,在根系吸水吸氮源汇项中引入了补偿性吸收机制。有机质模块完全来自Daisy模型,将有机质库划分为3个快库和3个慢库。利用改进的荷兰PS123模型实现了作物生长发育进程、干物质生产、干物质分配及作物产量的模拟,通过水氮胁迫校准因子来实现水氮限制下作物产量的模拟。最后应用华北地区（山东泰安）冬小麦-夏玉米轮作体系2 a的田间观测数据对该模型进行了校验。结果表明,剖面土壤水分和硝态氮浓度、叶面积指数、作物产量与实测值均吻合良好,模拟误差均在合理范围之内,特别是对产量的模拟较好,均方根误差为206-319 kg/hm^2,相关系数为0.90,模型效率值均大于0.75,一致性指数值均大于0.9。WHCNS模型能够较好地模拟土壤水分动态、氮素运移及去向、作物生长发育等过程,表明该模型适用于中国华北地区高度集约化的农田生产系统。展开更多
优化农田水氮管理措施可为实现粮食高产、资源高效及环境友好的目标提供科学依据。该研究以华北平原泰安地区为例,利用农田生态系统水热碳氮过程耦合模型(soil water heat carbon and nitrogen simulator,WHCNS)分别对冬小麦季设置的16...优化农田水氮管理措施可为实现粮食高产、资源高效及环境友好的目标提供科学依据。该研究以华北平原泰安地区为例,利用农田生态系统水热碳氮过程耦合模型(soil water heat carbon and nitrogen simulator,WHCNS)分别对冬小麦季设置的165个水肥组合和夏玉米季设置的55个水肥组合进行了情景模拟分析,在综合考虑农学、环境和经济效益的基础上,采用密切值法优化了农田水肥管理方案。结果表明:受到华北地区年内降雨分配不均的影响,冬小麦产量随着灌水量的增加呈先增加后稳定的趋势;而夏玉米产量与灌水量没有明显的关系。冬小麦和夏玉米产量均随着施肥量的增加而增加,后保持稳定。水分渗漏和氮素淋洗量均随着灌水量或施肥量的增加而显著增加。在研究区作物秸秆全部还田及高累积氮的条件下,冬小麦季灌水240 mm和施肥60 kg/hm^2(以N计,下同),夏玉米季不灌溉和施肥90 kg/hm^2分别为研究区当年冬小麦季和夏玉米季最佳的水肥管理方案。在所有水肥组合情景中,优化的水肥管理方案不仅能保证冬小麦-夏玉米最大周年产量的97%、具有较高的水氮利用效率和最佳的产投比,而且氮素淋洗和气体损失分别比最大值降低了77%和71%。因此,该方法可以用来优化华北平原农田的水肥管理措施。展开更多
文摘为探究土壤-作物系统水热碳氮耦合模型(Soil Water Heat Carbon and Nitrogen Simulation,WHCNS)在华北平原的适用性,本研究基于2年的夏玉米田间试验数据对WHCNS模型进行率定和验证。结果显示,经率定后的WHCNS模型可用于土壤水力特性、氮损失和作物生长发育的模拟。表明WHCNS模型具有精确模拟华北平原夏玉米生育期内土壤水力运动特性、氮损失和作物生长的能力。
基金supported in part by the Key R&D Program of Shandong Province,China (2023CXGC010703)the National Key Research and Development Program of China (2022YFD2300905-01)the Natural Science Foundation of Shandong Province,China (ZR2021MC123)。
文摘Selecting an appropriate planting density is an effective way to improve crop water productivity(WPC).However, there is a lack of research on the balance between evapotranspiration(ET) partitioning, water consumption, and grain production under different summer maize planting densities. To close this knowledge gap, a two-year field experiment was conducted in the North China Plain(NCP) to reveal the effects of different planting densities(HD: 100,000 plants ha^(-1);MD: 78,000 plants ha^(-1);LD:56,000 plants ha^(-1)) on ET partitioning, grain yield, and water productivity of summer maize. The water-heat-carbon-nitrogen simulator(WHCNS) model was employed to calculate ET partitioning and perform scenario simulation after calibration and validation. The results showed that compared to the LD treatment, ET of the summer maize and grain yield in the MD and HD treatments significantly increased. Model simulations showed that the ratio of evaporation to ET ranged from 25.6% to 30.7%and reduced as increasing planting densities. Increasing planting density enhanced total transpiration of summer maize more than 20 mm, comparing to LD treatment, and the most significant differences between various planting densities appeared at the mid-growth stage(August 1 to 31). Scenario simulations indicated that grain yield and WPCof summer maize were consistently higher in wet and normal years compared to drought years, exhibiting a trend of initially increasing and then decreasing with increasing planting density. The highest grain yield and WPCof summer maize were observed at a planting density of approximately 80,000 plants ha^(-1). The results provide theoretical support for selecting a summer maize planting density and effectively utilizing agricultural water in the NCP.
基金supported by the National Key Research and Development Program of China(2018YFD0800303)the Major Science and Technology Innovation Projects in Shandong Province,China(2021CXGC010804).
文摘The eutrophication of rivers and lakes is becoming increasingly common,primarily because of pollution from agricultural non-point sources.We investigated the effects of optimized water and fertilizer treatments on agricultural non-point source pollution in the Nansi Lake basin.The water heat carbon nitrogen simulator model(WHCNS model)was used to analyze water and nitrogen transport in wheat fields in Nansi Lake basin.Four water and fertilizer treatments were set up:conventional fertilization and irrigation(CK),reduced controlled-release fertilizer and conventional irrigation(F2W1),an equal amount of controlled-release fertilizer and reduced irrigation(F1W2),and reduced controlled-release fertilizer and reduced irrigation(F2W2).The results indicated that the replacement of conventional fertilizers with controlled-release fertilizers,combined with reduced irrigation,led to reduced nitrogen loss.Compared with those of the CK,the cumulative nitrogen leaching and ammonia volatilization of F2W1 were reduced by 8.90 and 41.67%,respectively;under F1W2,the same parameters were reduced by 12.50 and 15.99%,respectively.Compared with the other treatments,F2W2 significantly reduced nitrogen loss while producing a stable yield.Compared with those of the CK,ammonia volatilization and nitrogen loss due to leaching were reduced by 29.17 and 27.13%,respectively,water and nitrogen use efficiencies increased by 11.38 and 17.80%,respectively.F2W2 showed the best performance among the treatments,considering water and fertilizer management.Our findings highlight the effectiveness of optimizing water and fertilizer application in improving the water and nitrogen use efficiency of wheat,which is of great significance for mitigating nitrogen loss from farmland in the Nansi Lake basin.
文摘定量描述农田生态系统中土壤水分动态、碳氮循环过程和作物生长发育规律,对水氮资源高效利用、作物生产决策和环境保护具有十分重要的意义。该文在总结前人研究成果的基础上,引用了联合国粮食及农业组织的气象模块、荷兰的PS123作物模型和丹麦的Daisy模型的碳氮循环模块;借鉴了RZWQM和Hydrus-1D的水分溶质运移模块的相关理论,并在其基础上进行了修改与完善,构建了土壤-作物-大气系统水热碳氮耦合模拟模型WHCNS（soil water heat carbon and nitrogen simulation）。该模型以天为步长,考虑了气象条件、作物生物学特性和田间管理驱动。土壤水分入渗和再分布过程分别采用Green-Ampt模型和Richards方程来描述。土壤氮素运移使用对流-弥散方程来描述,源汇项中考虑碳氮循环的各个过程（有机质矿化、生物固持、尿素水解、氨挥发、硝化、反硝化和作物吸收等）,在根系吸水吸氮源汇项中引入了补偿性吸收机制。有机质模块完全来自Daisy模型,将有机质库划分为3个快库和3个慢库。利用改进的荷兰PS123模型实现了作物生长发育进程、干物质生产、干物质分配及作物产量的模拟,通过水氮胁迫校准因子来实现水氮限制下作物产量的模拟。最后应用华北地区（山东泰安）冬小麦-夏玉米轮作体系2 a的田间观测数据对该模型进行了校验。结果表明,剖面土壤水分和硝态氮浓度、叶面积指数、作物产量与实测值均吻合良好,模拟误差均在合理范围之内,特别是对产量的模拟较好,均方根误差为206-319 kg/hm^2,相关系数为0.90,模型效率值均大于0.75,一致性指数值均大于0.9。WHCNS模型能够较好地模拟土壤水分动态、氮素运移及去向、作物生长发育等过程,表明该模型适用于中国华北地区高度集约化的农田生产系统。
文摘农业生产管理系统模型输入参数多,参数率定过程十分耗时费力,大大限制了其推广应用。该研究以华北平原2 a的冬小麦-夏玉米田间试验观测数据为基础,使用PEST(parameter estimation)参数自动优化工具对土壤-作物-大气系统水热碳氮过程藕合模型(soil water heat carbon and nitrogen simulator,WHCNS)的土壤水力学参数、氮素转化参数和作物遗传参数进行自动寻优,同时计算分析模型参数的相对综合敏感度,并将优化结果与土壤实测水力学参数和试错法的模拟结果进行比较。参数敏感度分析结果表明,18个模型参数的相对综合敏感度较高,其中土壤水力学参数普遍具有较高的敏感度,以饱和含水率敏感度最高;作物参数中,作物生长发育总积温和最大比叶面积具有较高的综合敏感度;而氮素转化参数的敏感度远低于土壤水力学参数和作物参数。评价模型模拟效果的统计性指标(均方根误差、模型效率系数和一致性指数)表明,PEST法比实测水力学参数的模拟精度有所提高,其中土壤含水率、土壤硝态氮含量、作物产量和叶面积指数的均方根误差分别降低了61.8%、23.5%、73.6%和23.3%。同时PEST法比试错法对土壤水分和作物产量的模拟精度也有较大提高,但对土壤氮素和叶面积指数的模拟精度提高不明显。由于该方法大大节约了模型校准时间,在较短的时间内获得了明显高于试错法的模拟精度,因此PEST软件在WHCNS模型参数自动优化中是一个值得推广的工具。
文摘优化农田水氮管理措施可为实现粮食高产、资源高效及环境友好的目标提供科学依据。该研究以华北平原泰安地区为例,利用农田生态系统水热碳氮过程耦合模型(soil water heat carbon and nitrogen simulator,WHCNS)分别对冬小麦季设置的165个水肥组合和夏玉米季设置的55个水肥组合进行了情景模拟分析,在综合考虑农学、环境和经济效益的基础上,采用密切值法优化了农田水肥管理方案。结果表明:受到华北地区年内降雨分配不均的影响,冬小麦产量随着灌水量的增加呈先增加后稳定的趋势;而夏玉米产量与灌水量没有明显的关系。冬小麦和夏玉米产量均随着施肥量的增加而增加,后保持稳定。水分渗漏和氮素淋洗量均随着灌水量或施肥量的增加而显著增加。在研究区作物秸秆全部还田及高累积氮的条件下,冬小麦季灌水240 mm和施肥60 kg/hm^2(以N计,下同),夏玉米季不灌溉和施肥90 kg/hm^2分别为研究区当年冬小麦季和夏玉米季最佳的水肥管理方案。在所有水肥组合情景中,优化的水肥管理方案不仅能保证冬小麦-夏玉米最大周年产量的97%、具有较高的水氮利用效率和最佳的产投比,而且氮素淋洗和气体损失分别比最大值降低了77%和71%。因此,该方法可以用来优化华北平原农田的水肥管理措施。
