土壤中溶质运移的过程、规律和机理是土壤溶质运移研究的主要内容。本文的目的是对模拟非饱和介质中水分和溶质迁移的二维数值模型SWMS–2D 进行研究和验证。以硝酸盐形式存在的溶解氮是地下水中最常见的污染物,将硝态氮视为土壤溶质,考虑其根系吸收、生物固持、吸附、解吸、硝化和反硝化等作用,土壤表面即上边界条件用大气边界条件描述,下边界条件定为第一类边界条件,在田间条件下对模型作了检验。
The purpose of this thesis is to verify a kind of solute transport model：SWMS–2D computer program.Nitrate is counted as the main solute because it is one of the most popular contaminant in groundwater.The program numerically solves the Richards'equation for saturated–unsaturated water flow and the convection–dispersion equation for solute transport.The flow equation incorporates a sink term to account for water uptake by plant roots.The solute transport equation includes provisions for linear equilibrium adsorptionzero–order productionand first–order degradation.Soil is divided into3layers.Experiments were completed in field soiLand get some results.
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