Soil Chemical Characteristics And Risk Assessment For A Certain Area In Central South In China

Land is the basis for human survival,and the quality of land directly affects the ecological environment of the region.The growth of crops and the health of the population are closely related to the quality of the land.This paper took soil as the research object through the geochemical survey and made a map with MAPGIS software according to the type of element based on the "1:50000 land quality geochemical survey standards".The harmful elements,associated with the health of the human body and the beneficial elements of the environmental impact of the elements were analysised,and provided the important basis for the study of local disease and ecological environment coordinated development.The research mainly includes the following aspects:(1)The basic situation of the land and the distribution of soil elements in the study area were clear.The study area is located in the southern province,the region of the East Dongting Lake of the Yangtze River plain south bank,located at the eastern end of Xuefeng Mountain and its remaining vein belt.Soil surface samples(1-20cm)were collected.Multi element test and analysis were carried out.The results of comprehensive analysis showed that the soil was in the two level of quality,and the As and Cd elements appeared three individual quality points.Among them,the Cd element has super three quality points.(2)Ecological risk assessment in the study area were accomplished.In this paper,the single-factor pollution index method and Nemero index method were used to comprehensively evaluate the soil in the study area.The results showed that the soil in the study area was polluted by Pb,Cd,Hg and As,respectively,and the potential risk level of Cd was higher.The risk level is mild pollution.The conclusions drawn from the risk assessment can provide an important basis for the prevention of endemic diseases.Using USEPA(US Environmental Protection Agency Risk Assessment Guide)to digest intake of chemical substances in the soil,and calculate the ecological risk of the study area by measuring the skin contact intake of chemical substances in the soil.The calculations show that the risk of cancer in children in the study area is higher than that of adults in the study area.Additionally,the higher skin contact with Cd,the higher in the risk of endemic disease is.