Research Progressing of Present Contamination of Cd in Soil and Restoration Method
WANG Weizhong1, XU Weihong1†,ZHOU Kun1, XIONG Zhiting21. College of Resources and Environment, Southwest University, Chongqing 400716, China;2. School of Resource and Environmental Sciences, Wuhan University, Wuhan 430079, Hubei, China
Cadmium is one of the important contaminative heavy metals. Due to continuous increase of discharge of Cadmium in industrial and agriculture production, cadmium contamination of soil is more and more serious day by day, which seriously threatens ecological environment and human health. Treatment of cadmium becomes an urgent issue and research hot point. At present, remedy for cadmium pollution upon soil mainly are physical restoration, chemical restoration and biological restoration, also there are measurements by means of adding external source matter and selecting low-Cd-accumulation varieties so as to reduce cadmium harm upon agricultural products. This article introduces in detail the resource of cadmium in soil and the present condition of cadmium pollution in farmland and processing of domestic cadmium pollution research, processing stage of domestic and foreign research of restoration of cadmium polluted soil as well as various peculiarities of repair methods. Finally, the expectation of research is discussed.
Key words:cadmium pollution in soil; engineering method; chemical restoration; biological restoration; agricultural technique measurements
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