天津地区表土PAHs的多元空间估计及精度分析

Multivariate spatial estimation and accuracy analysis of topsoil PAHs in Tianjin area.

在天津地区表层土壤多环芳烃(PAHs)采样数据基础上,应用协同克立格方法(CK)对PAHs进行多元空间估计,并探讨了普通克立格方法(OK)与CK在空间估计方面的精度问题.结果表明,PAHs各组分在空间分布上存在着很大的差异,绝大多数组分在市区都有高值区,其次分布在塘沽和汉沽区以及西青区.而低值区域主要分布在北部山区,以及南部的大港区、静海县.通过估计误差的比较发现,CK方法的估计误差平均为4.22%,而OK方法的估计误差平均为8.56%.协同克立格法能够很好地对PAHs进行多元空间估计,相对于普通克立格法来说,估计精度有了较大的提高.

Based on the sample data of topsoil PAHs in Tianjin areas, applying co-kriging techniques to carry out multiple statistic spatial estimation on PAHs, and further the accuracy problem of ordinary kriging and co-kriging in spatial estimation was studied. Each group of PAHs existed very great variation on spatial distribution. Most groups had high value area in city area, next distributed in Tanggu and Hangu areas and Xiqing area. While low value area distributed mainly in northen mountain area, and south part Dagang and Jinghai districts. The accuracy of interpolation was compared between ordinary kriging and co-kriging. The average estimated error of co-kriging was 4.22% while the average estimated error of ordinary kriging was 8.56%. Compared with ordinary kriging, the interpolation accuracy of co-kriging was improved.