【摘要】 本文以江西省贵溪市江西铜冶炼厂周围的土壤重金属污染区(面积7.7km2)为例,研究了基于GIS的地统计学方法在丘陵红壤区土壤重金属复合污染空间变异分析上的应用,提出了一个空间变异分析步骤:(1)利用DGPS定位,以50~200m的随机网格采集土壤样品;(2)分析土壤重金属含量数据的分布类型和空间分布趋势,通过数据转换去除数据趋势;(3)计算半方差函数并选择最佳的拟合模型和参数;(4)通过交叉验证选择合适的克立格方法;(5)通过空间插值,绘制重金属污染空间分布图,分析空间变异规律和影响因素。空间分析结果表明,Cu和Cd的复合污染是铜冶炼厂污染区的主要污染特征,基于ArcGIS的地统计学分析模块可以较准确地分析丘陵区土壤重金属复合污染的空间变异特征。更多还原

【Abstract】 A GIS-based geostatistical method was put forward for analyzing spatial variation of combined heavy metal pollution in soils. As a case study, an area, about 7.7 km2, around the Jiangxi Copper Smeltery in a red soil hill region in Guixi County, Jiangxi Province was selected. The sequence of the analysis method goes as follows: a) collect soil, plant or water samples by random grid from 50m to 200m with DGPS, and analyze the samples for heavy metal contents and other properties; b) explore distribution pattern and spatial variation of the data, then transform the data to get rid of the trend; c) calculate semivariogram, and select the best model and appropriate parameters; d) select the best kriging method based on cross validation; e) interpolate soil heavy metal contents and draw a heavy metal pollution map, then analyze spatial distribution characteristics and their controlling factors. The results show that there is combined Copper and Cadmium pollution in the study area, and the above method based on the geostatistical module in ArcGIS can exactly predict the spatial distribution pattern of combined heavy metal pollution in the hill region.更多还原