Study On The Environmental Effect Of Heavy Metals In Dexing Copper Mine Area, Jiangxi Province

The exploitation and utilization of mineral resource is becoming an important means to economic growth and development.It made enormous contribution to development of society and prosperity of economy through exploiting and smelting.But in recent years,people need more and more resources with the rapid economic development and a lot of environmental problems accumulate from long-term exploitation of some old mines.These all cause that research and treatment of environment in mine area becomes an important problem.This paper chose Dexing Copper Mine to be the research object of environmental problem in mine.According to the two pollution source of Dexing Copper Mine(Zhujia village rock drain-dump and tailing dam),we collected water samples,soil sample,plant samples and tailing samples to study the distribution of heavy metals.And also we analysed elements speciations of soil and tailing samples.The result was that because of the Zhujia village rock drain-dump pollution the content of Cu,Pb,Zn was large and the source region of Dawu River was seriously polluted by Cu,Pb,Zn.The content of Cu increased while Ph decreased in soil samples.Water samples in upstream of Dawu River was polluted by Cu and Zn whose content seriously exceeded national water standard of levelâ…¢.Content of Cu and Zn in water decreased in middle reach and downstream of Dawu River.Heavy metals more distributed in soil samples which more closed to Dawu River.The content of Cu,Pb,Cd,As,Mo was bigger in cabbage and paddy in Dawu River area than in the background area.The content of Pb was twice than national standard of grain.The result of speciation analysis showed organic fraction of Pb had been the biggest part which may caused the content of Pb in paddy.The carbonate fraction of Cd was about 30%,which could pollute environment.The organic fraction,hydrotrope,absorbate and carbonate fraction of Cd also have a large percent,which would pollute the soil easily.The content of Cr,Cu,Mo in surface layer is higher than in deeper layer and the content decease with the depth in 4~# Tailing.While the content of Cu,Mo in surface layer is lower than in deeper layer in 1~# Tailing.These difference may be caused by emission time.In the two tailings most of the heavy metals exists in the form of sulfide fraction which was stable in reducing environment.Content of Cu,Mo,Pb,Zn,Cd in soil in 4~# Tailing area decreased while the distance to 4~# Tailing dam increased.Content of Cd and Pb in paddy in 4~# Tailing area was above the national grain standard,which also decreased with the increased distance to 4~# Tailing dam.The content of Pb was quadruple than the national vegetable stamdard in cabbage which growed in 1~# Tailing village after reclamation.The absorbate and carbonate fraction of Cd was about 20%which may caused the content of Cd in cabbage.