冬小麦生长条件下土壤氮素运移动态的数值模拟

将土壤溶质运移理论和土壤微生物化学、植物生理学有机地结合起来,建立了农田土壤氮素运移、转化与吸收的综合数学模型。运用该模型对中德合作项目试验田1999～2000年冬小麦优化施肥与传统灌溉和优化施肥与优化灌溉两小区的土壤水分和氮素运移动态及干物质产量进行了模拟。模拟结果与实测数据吻合较好。两小区土壤剖面埋深165cm处硝态氮淋失量的计算结果表明：与传统灌溉方式相比,优化灌溉方式的土壤硝态氮的淋失量明显减少。用验证后的数学模型在计算机上进行了几种不同灌溉方案下土壤水氮运移动态及干物质产量变化的数值试验,结果表明：在喷灌条件下,冬小麦以每l0d灌溉一次,每次20mm水量的灌溉方式较优。

Numerical simulation of nitrogen transport during the growth of winter wheat

The object of this study is to improve the existing model for predicting the behavior of nitrogen in soil, uptake by plants and migration towards ground water. A comprehensive mathematical model for describing the transport, transformation of nitrogen in soil was established based on the theories of soil physical,chemical,biological and microbiological process. The model is applied to simulate the water movement, nitrogen transport and crop yield in two experimental fields. The simulation result is in good agreement with observation data.It is found that under the condition of sprinkler irrigation, the best sheme for winter wheat is to carry out irrigation every 10d with water depth 20mm each time. Following this irrigation scheme the dry matter production can be improved and the amount of nitrate-nitrogen leaching will be reduced.