摘要
Abstract
It is of great significance to study the status and sources of heavy metal contamination in soils sur-rounding aquaculture zones for soil pollution control.In this study,farmland soils surrounding aquaculture zones in the southwestern Nanyang Basin were selected as research object.The contents of Cd,Hg,As,Pb,Cr,Cu,Ni and Zn in soils were determined.The single factor pollution index(Pi)method and Nemerow comprehensive pollution index(PN)method were used to evaluate the heavy metal pollution status.Geosta-tistical analysis and multivariate statistical analysis were combined to explore the spatial distribution patterns and sources of soil heavy metals.The results showed that except for Cd,Cu and Zn,the contents of other heavy metals in farmland soil in the study area did not exceed the screening value of soil pollution risk of agri-cultural land specified in Soil environmental quality risk control standard for soil contamination of agricul-tural land(GB 15618-2018).The average contents of Cd,Hg,Pb,Cr,Cu,Ni and Zn were all higher than the background values of soil environment in Henan Province,and there was a certain enrichment trend.The re-sults of single factor pollution index showed that the soils in the study area were slightly polluted by Cu,Zn and Cd,and some of the sampling points were moderately polluted by Cd.The results of Nemero comprehen-sive pollution index showed that the soil in the study area was in a clean to slightly polluted state.The spatial distribution map of soil heavy metals showed that the peak areas of Cd,Hg,Zn,Cu and Ni had a high degree of coincidence,and there were many cross areas in the peak areas of Cr,Pb and As.The principal component analysis showed that the pollution of Hg,Cu,Zn,Cd and Ni in the soil of the study area was mainly due to the composting of animal manure and agricultural fertilization activities,which constitute the"agricultural pollu-tion source",while the pollution of As and Pb was mainly due to human activities,which constitute the"in-dustrial source".关键词
土壤重金属/污染特征/风险评价/来源分析Key words
soil heavy metals/pollution characteristics/risk assessment/source analysis分类
资源环境
