Using cokriging method for improving estimates of spatial distribution of soil heavy metal in suburban of Beijing
Accurate delineation of spatial distribution of heavy metal concentrations in soil is essential for its pollution assessment and remediation. A total of 322 topsoils were sampled in the Daxing County of Beijing. Soil organic matter (SOM) was determined for each soil sample. Seventy soil samples were selected and their heavy metal concentrations of Cu, Pb, Ni and Hg were determined. The ordinary kriging (OK) and cokriging (COK) were used to estimate the unobserved points for these heavy metals and compared with each other in terms of their accuracy. The results indicated that soil heavy metal concentrations had a close relationship with SOM. The estimates obtained from the COK method by taking SOM (322 samples) as auxiliary variable resulted in more accurate than these from the OK method. The predicted mean standardized error could be decreased from 0.54％ to 39.9％ comparing with the OK method and the predicted root-mean-square standardized error could be decreased from 2.0％ to 75.0％. The correlation coefficient between the measured and predicted values, increased from 26.8％, 62.1％, 22.1％, 66.1％ to 46.6％, 63.3％, 51.1％, 72.0％ for soil Cu, Hg, Ni and Pb concentration, respectively.
Soil heavy metals soil organic matter ordinary kriging cokriging spatial distribution
K. L. Hu B. G. Li H. Li F. R. Zhang
College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100094, P. College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100094, P.
国际会议
第九届痕量元素生物地球化学国际会议(9th International Conference on the Biogeochemistry of Trace Elements)
北京
英文
67-68
2007-07-15（万方平台首次上网日期，不代表论文的发表时间）