区域浅层地下水埋深和水质的空间变异性特性

对华北冲积平原曲周县的139个观测点取样分析,测定了其浅层地下水埋深、地下水含盐量以及硝酸盐含量。应用地质统计学的方法对所取的数据进行了分析,结果表明,地下水埋深服从正态分布,地下水含盐量服从对数正态分布,硝酸盐含量既不服从正态分布也不服从对数正态分布。并且按一定的精度和置信水平确定了这三项的合理取样数目。通过半方差函数分析,发现这三者在一定范围内存在空间相关性。采用Kriging方法对未测点进行了估值,绘制了等值线图,这对于合理利用浅层地下水资源、防治土壤的次生盐渍化及地下水的硝酸盐污染有着直接的现实意义。

Spatial Varibility of the Regional Shallow Groundwater Depth and Water Quality

139 observing points were sampled in Quzhou County in Huabei plain. The depth of groundwater, salt and nitrate content of groundwater were measured. The geostatistics theory was applied to analyze the data. The results indicated that the depth of groundwater showed a normal distribution, the salt content showed a lognormal distribution and the nitrate content showed neither a normalnor a lognormal distribution. The rational sampling number was determined within a given precision at a known confidence level. By the semivariance analysis those observ items were correlated in a given spatial range. The Kriging method was applied to estimate the unobserved points and generate the contour map. These results show some merit in rational using the groundwater resource and preventing soil secondary salinization and the nitrate pollution.