土壤-作物-大气系统水热碳氮过程耦合模型构建  

Coupled simulation of soil water-heat-carbon-nitrogen process and crop growth at soil-plant-atmosphere continuum system

作　　者：梁浩[1] 胡克林[1] 李保国[1] 刘海涛[1] 

机构地区：[1]中国农业大学资源与环境学院,农业部华北耕地保育重点实验室,北京100193

出　　处：《农业工程学报》2014年第24期54-66,共13页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金项目(41171184;51139006);农业科研杰出人才及其创新团队项目(2012022)

摘　　要：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。The quantitative description of soil water flow, carbon（C） and nitrogen（N） cycles, and crop growth processes at soil-plant-atmosphere continuum system is important for improving water and N use efficiencies and decision-making of crop production and environmental protection in the North China Plain（NCP）. The objective of this study was to develop a water and N management model for intensive cropping systems and agricultural management practices in NCP. Based on the previous research findings, a coupled model（Soil Water Heat Carbon and Nitrogen Simulation, WHCNS） model was established. The model included 5 main modules： soil water, soil heat, soil C, soil N, and crop growth. The Penman-Montheith method from the Food and Agriculture Organization of the United Nation was used to calculate the reference crop evapotranspiration. The method for simulating soil water movement and heat transfer was directly introduced from the HYDRUS1 D and RZWQM models. The PS123 model from the Netherlands was used to simulate crop growth. The simulation of C and N cycles was done by the Daisy model from Denmark. The model ran on a daily time step and was driven by the meteorological and crop biological variables, and agricultural management practices. The soil water infiltration and redistribution processes were described by Green-Ampt and Richard＇s equations, respectively. Soil N transport simulation was based on the modified convection-dispersion equation. The source-sink term of N transformation and transport included mineralization of soil organic N, immobilization in biomass, urea hydrolysis, ammonia volatilization, nitrification, denitrification, and crop uptake. The compensatory absorption mechanism was introduced in crop water and N uptake. The organic matter pools were divided into 3 active and 3 stabile C pools. The improved version of the PS123 model was applied to simulate crop development stage, dry matter production and allocation, and crop yield. The crop yield under water and N stress was calculated

关 键 词：作物 生长 土壤 SPAC系统 水分运动 碳氮循环 WHCNS模型 

分 类 号：S152[农业科学—土壤学]