排水农田氮素运移,转化及流失规律的研究

在总结文献和室内外试验基础上，对排水条件下氮素运移，转化及流失规律进行了分析研究；建立了一维、二维土壤水和地下水中氮素运移转化数学模型；探索了有限元数值计算法耦合求解水流和氮素运移模型，并提出了改进流线追踪法，克服已有简易计算方法中采用经验数据，精确方法计算繁复，且耗机时多的缺点，可用于排水农田氮素运移长期预报。

The Study of the Transport, Transformation and Losses of Nitrogen in Drained Agricultural Lands

On the basis of literature review and laboratory and field experiments, the patterns of transport,transformation and losses of nitrogen under the conditions of land drainage are analyzed, one and two dimensional mathematical models for transport and transformation of nitrogen in soils and groundwater are established, the methods for the simultaneous solution of flow and nitrogen transport equations are investigated, a modified travel-time method for estimating nitrogen concentration in drainage effluent, which can be used for long-time prediction of nitrogen in drained agricultural lands is also proposed.