Abstract:

In order to study the effects of plant in-situ intercept heavy metals in soil waste residue and configuration mode in lLead-zinc mining area, both various of plant cultivation and the water sample in runoff plots were studied. The results of 3-year old plants suggested that Boehmeria nivea, Cortex Meliae and Broussonetia could reduce the load output of Pb in runoff water in abandoned tailings dam 9.04%-9.64%; Koelreuteria bipinnata, Broussonetia, Phragmites hirsute, Cortex Meliae and Robinia pseudoacacia L. could reduce the load output of Cd 67.0%-75.86%; Broussonetia, Festuca arundinacea, Robinia pseudoacacia L. Koelreuteria bipinnata, Phragmites hirsute, Bermudagrass Cynodon dactylon (L.) Pers and Miscanthus floridulu (Labnll.) Warb could reduce the load output of Cu 52.64%-70.97%; Robinia pseudoacacia L. and Ligustrum lucidum could reduce the load output of Zn 74.99%-78.35%. In heavy-metal polluted woodland, Robinia pseudoacacia L. could reduce the load output of Pb in runoff water 40.96%; Cortex Meliae could reduce the load output of Cd in runoff water 60.42%. The contents of Pb, Cd, As and Zn reduced 31.87%, 41.28%, 29.48%, 38.45% by the enrichment of Broussonetia, respectively and reduced 27.31%, 39.52%, 33.47%, 27.59% by the enrichment of Ligustrum lucidum, respectively in the tailings of lead-zinc mine. There are 2 mechanisms of plant in-situ intercept and restoration heavy metals. On one hand, the plants accumulated heavy metal in soils, on the other hand, the chemical forms of soil heavy metals changed which needed further study.