基于Cokriging的土壤重金属空间变异研究——以昆山市为例

土壤重金属来源及空间分布是土壤学及环境学研究的热点问题。地统计学是土壤元素空间变异研究的有效方法以昆山市土壤重金属分布为例,先利用多元回归分析方法,提取与重金属含量显著相关的因子,再利用协同克里格方法研究了土壤理化性质和土壤重金属含量的相互关系,最后比较协同克里格与普通克里空间预测的精度。研究表明Hg、As、Cu、Pb的精度分别提高了2.75%、2.13%、0.17%和0.43%,cr、Zn和Cd 3种元素空间预测精度没有显著提高。

Study on Spatial Variation of Heavy Metals in Soil Based on Cokriging Method——Taking Kunshan City as Example

Heavy metal sources and distributions in soil is a key issue in soil and environmental sciences. Geostatistics is a useful tool to analyze spatial variation of elements in soil. In this paper, we used cokriging to study the soil heavy metal distribution in Kunsan city. First, standard regression was used to extract factors, which were significantly correlated with heavy metal contents. Second, auxiliary variables were combined with cokriging to study the physicochemical characteristics of soil and heavy metal contents. Finally, accuracies of ordinary kriging and cokriging were compared. The results showed that accuracies of Hg、As、Cu、Pb elevated by 2.75%、2.13%、0.17% and 0.43%, but there were no significant increase of Cr、Zn and Cd.