依据2006—2009年间采集的区内1092件浅层地下水无机分析和现场测试数据,采用地统计学分析方法,分析了黄河下游冲积平原地下水中砷的空间变异特征及在人类活动影响下的污染现状。全区26.65%的样品砷含量超过饮用水标准,超标区域面积占全区总面积的17.3%。浅层地下水中砷的统计特征表明砷的离散程度和变异系数均较高;空间变异特征显示砷在空间上的分布各向异性,砷含量分布差异与地下水流向关系不密切,不同浓度的分布主要受原生条件和污染源的影响;区内约7%的浅层地下水样品砷的浓度由人类活动影响形成,其中12%的砷污染样品源于养殖场砷污染,养殖场内浅层地下水砷检出率、超标率均为全区的2倍;砷污染源包括农村分散养殖场牲畜废弃物排放、含砷农药的施用、工业污水的不达标排放等。
Based on the inorganic analysis of 1092 groundwater samples collected from 2006 to 2009 in Yellow River Plain and using the method of geo-statistics,this paper discussed the spatial variation and pollution of arsenic in shallow groundwater under the influence of human activities in this region.26.65% of the samples exceeded the Drinking Water Standard in arsenic concentration,and the area surpassing the set standard accounted for 17.3% of the total area.The degree of dispersion of shallow groundwater was high and the coefficient of variation was over 100%.The spatial distribution of arsenic was anisotropic.The relationship between arsenic distribution and groundwater flow was not close,and the native condition and impact of pollution sources seem to be the main reasons.7% of shallow groundwater samples suffered from arsenic pollution from human activity,and 18% of the arsenic polluted samples were caused by livestock breeding farms.The detection rate and exceeding rate of samples from livestock breeding farms was 2 times that of the whole study area.The arsenic pollution source included the animal waste from the scattered livestock breeding farms,the application of arsenic-bearing pesticides,and the discharge of industrial wastewater.