坡地氮磷流失过程模拟  

Simulation of nitrogen and phosphorus loss in sloping field

作　　者：王建中[1] 刘凌[1] 宋兰兰[1] 

机构地区：[1]河海大学水文水资源与水利工程科学国家重点实验室,江苏南京210098

出　　处：《水科学进展》2009年第4期531-536,共6页Advances in Water Science

基　　金：国家自然科学基金重点资助项目(50239030)~~

摘　　要：根据农田坡面氮、磷流失的主要过程,建立了基于次降雨事件的坡面氮、磷迁移模型。模型采用改进的Green-Ampt方程和运动波方程计算下渗与坡面流,土壤侵蚀采用修改的欧洲土壤侵蚀模型计算,用考虑了侵蚀影响与扩散作用的迁移模型计算坡面氮、磷迁移过程,采用一维对流扩散方程计算氮、磷在土壤中的迁移过程。利用室内人工降雨资料对模型进行了率定及验证。结果表明,模型可以较好地模拟地表径流中氮、磷浓度,率定期与验证期模型效率系数均在0.89以上。根据坡地氮、磷流失机理,分析了降雨强度与地表坡度对坡面径流中氮、磷浓度的影响。An event-oriented, nitrogen （N） and phosphorus （P） transport model is developed to simulate the N and P transfer processes in farmland slope during the rainfall period. The Green-Ampt infiltration equation modified and the kinematic wave equation are used to estimate the infiltration volume and the overland flow. The soil erosion is computed with the revised Euro pean soil erosion model. N and P transfer from soil to overland flow is simulated with the model including erosion driven processes and diffusion process. N and P transport within the soil profile is described by the 1D advection-diffusion equation. The model calibration and validation are performed with the measured data derived from the indoor artificial precipitation experiment, and the results show that the model can be used to simulate the N and P concentration in overland flow effectively, and the efficiency coefficients during calibration period and validation period are both above 0.89. The relationship between rainfall intensity, slope and N, P concentration in overland flow are analyzed.

关 键 词：坡面流 质量传递 水污染 氮 磷 数学模型 

分 类 号：X143[环境科学与工程—环境科学]