太原污灌区土壤重金属和盐分含量的空间变异特征

在面积为2.7万hm^2的太原污灌区布设土壤取样点49个,测定了耕层土壤中重金属Hg、Cd、Pb、盐分、氯离子含量及pH，应用地统计学的方法分析了数据的统计特征值和结构特征，结果表明：铅和盐分服从正态分布，氯离子服从对数正态分布，其它无分布类型，拟合得到Hg、Pb、盐分的半方差函数模型为指数型，镉和氯离子为球型，pH为高斯型，这些测定项目有在一定范围内存在空间相关性性。用Kriging内插法对未测点重金属及盐分进行最优估计，并绘制了等值线图，可更直观地反映出污灌区土壤重金属及盐分的空间变异特征。

Spatial variabilities of heavy metals and salt contents in soils of Taiyuan sewage irrigation region

Forty nine soil samplers were collected from 27000 hm 2 of Taiyuan sewage irrigation region. Hg, Cd, Pb, salt content , Cl - and pH were measured. A geostatistics method was used to analyze the statistical feature of these data. Soil heavy metal Pb and salt distributed normally and Cl - distributed lognormally, but others showed neither normal nor lognormal distribution. The semivariogram models of Hg, Pb and salt were exponential, the model of Cd and Cl - were spherical, the model of pH was gaussian. These observed items were correlated in a given spatial range. The Kriging method was applied to estimate the unobserved points and their contour maps were obtained. The spatial variabilities of the heavy metals and salt in the sewage irrigation region could be reflected clearly in the maps.