重金属在土壤-地下水中的迁移模型研究——以山西、陕西黄土高原塬区为例

Research on Migration Model of Heavy Metals in Soil-Groundwater——Take Loess Plateau Area in Shanxi and Shaanxi as an Example

随着工业的发展,我国地下水重金属污染问题逐渐突出.以山西、陕西黄土高原塬区为研究对象,通过分析影响重金属污染物在黄土迁移中的各个因素,构建黄土高原塬区重金属迁移的概念模型.通过降雨入渗Kostiakov三参数入渗经验模型、重金属在土壤非饱和带迁移的一维对流-弥散方程以及重金属进入地下潜水的稀释模型的耦合,重点考虑黄土高原地区降雨条件下,重金属随降雨入渗水分的下渗迁移.将该模型与前人研究的饱和-非饱和带迁移模型进行对比分析,利用MATLAB软件进行编程对该模型模拟验证.结果表明,该模型具有普适性,可以利用该模型预测土壤风险值,为常规评估与高层次风险预测提供一定的理论支撑.

With the development of industry,the problem of heavy metal pollution in groundwater in our country becomes increasingly prominent.Taking the loess plateau of Shanxi and Shaanxi as the research object,through analyzing various factors that affect the migration of heavy metal pollutants in the loess,a conceptual model of heavy metal migration in the loess plateau is constructed.Through the coupling of the rainfall infiltration Kostiakov three-parameter infiltration empirical model,the one-dimensional convection-dispersion equation for the migration of heavy metals in the soil unsaturated zone,and the dilution model of the heavy metals entering the underground water.The emphasis is on the infiltration and migration of heavy metals with rainfall infiltration under rainfall conditions in the Loess Plateau.The model was compared and analyzed with the saturated-unsaturated band studied by previous researchers,and the model was simulated and verified by programming using MATLAB software.The model is universal and can be used to predict soil risk values.The model can provide certain theoretical support for routine assessment and high-level risk prediction.