生态环境学报2018，Vol.27Issue(5)：933-941,9.DOI:10.16258/j.cnki.1674-5906.2018.05.019
北京城区绿地土壤重金属污染评价与空间分析
Pollution Assessment and Spatial Structure Analysis of Heavy Metals of Greenbelt Soil in Beijing Urban Area
摘要
Abstract
In order to reveal the pollution degrees, influence factors and spatial structure characteristics of greenbelt soils heavy metals in Beijing urban area, as well as provide a theoretical basis for Beijing to protect the environment and prevent greenbelt soil polluted by heavy metals. The concentrations of Pb, Cd, Ni, Hg and As in 151 greenbelt surface (0~20 cm) soil samples, which were collected from Park green area, Street green area, Residential green area and Affiliate green area, were detected. Then the influence factors and degrees of pollution and spatial structure characteristics of heavy metals in the soils were analyzed by applying the Nemerow integrated pollution index and Geo-statistics. The results showed that average values of total Pb, Cd, Ni, Hg and As were 29.89, 0.33, 23.89, 1.42 and 7.54 mg·kg-1, respectively. The greenbelt soil was polluted slightly, and the Nemerow integrated pollution index of the four heavy metals was 1.19. Single-factor pollution index of Hg was 1.54, which indicated low pollution level, while all of other four heavy metals posed no pollution and the single-factor pollution index of was all less than 0.7. Park green area was polluted slightly, and the Nemerow integrated pollution index of the four heavy metals was 1.81. Single-factor pollution index of Hg was 1.37, which indicated low pollution level, while none of other three green area had been polluted by heavy metals. According to the semivariogram fitting, the spatial autocorrelation of these four heavy metals was moderate. Pb and Cd fit the spherical model and the ratios of nugget and still were 65.03% and 43.12%, respectively. Hg fit to Gaussian model and the ratios of nugget and still was 41.3%. Ni and As fit the exponential model and the ratios of nugget and still were about 44.35% and 49.96%, Pb, Cd and As were isotropy, Hg and Ni were anisotropy. High-value areas of Ni and As were in the north region, high-value areas of Pb Hg was in the central region, and showed a trend of decreasing in the area, and distribution of Cd was fragmented and looked irregular. The pollution and spatial structure of these five heavy metals were both influenced by structural and random factors, and the degrees of being influenced by random factors were in the order of Pb>As>Ni>Cd>Hg.关键词
北京/绿地土壤/重金属/空间结构/地统计学Key words
Beijing/greenbelt soil/heavy metals/spatial structure/geo-statistics分类
资源环境引用本文复制引用
杨少斌,于鑫,孙向阳,张骏达,傅振,李婧..北京城区绿地土壤重金属污染评价与空间分析[J].生态环境学报,2018,27(5):933-941,9.基金项目
北京市科技计划课题(Z161100001116061) （Z161100001116061）
中国工程院咨询研究项目(2014-XZ-11-02) （2014-XZ-11-02）
