The paper predicts the changing tendency of groundwater resource in Changma alluvial fan by numerical modeling, applying the method of finite difference and irregular polygon cells.
应用有限差分方法，采用不规则多边形剖分，对昌马冲洪积扇区地下水资源数量的变化趋势进行了模拟计算。
2
The Nitrate concentrations in groundwater in the alluvial - diluvial fan of Zhangjiakou area has increased year by year.
张家口冲-洪积扇区地下水中的硝酸盐含量逐年升高。
3
More than half of the total groundwater in the working area is poor in quality, and occurs mainly in the middle and lower Liaohe alluvial plain.