| An extensive ecological survey and sampling of soils and dominant plants were conducted in three typical copper minelands(Lala,Liwu and Yangziling) in Sichuan. The soil chemical properties and hevry metal concentrations were determined.Then the utilization of the single pollution index and Nemerow index assessment was made to evaluate the contamination of heavy metal in the wastelands soil. It was to investigate the heavy metal accumulation by the dominant plants and find out the suitable plants to accumulate the heavy metals and to provide some scientific basis and materials for the ecological restoration of the copper wasteland in Sichuan. The results were as follows:(1) The soil of mining wastelands is acidity(pH averagely among 4.99-6.91), and the organic matter content of the difference(0.3-23.71g.kg-1), but the total phosphorus,the total nitrogen is-poor(<0.8 g.kg-1).The maximum organic averagely content appeared in the lala copper mine(12.21 g.kg-1); The TN and TP in the Yangziling mine was slightly higher than the others(0.94 g.kg-1 and 1.04 g.kg-1). The Zn and Cd content in three mining areas, Cu content in Lala mineing area and Yangziling mining area had exceeded the third-level of the soil environment quality, which became the main disadvantage factor influencing plant growth.(2)By the the general trend of heavy metal pollution of the three copper mines was similar, but also with differences. The three mining areas were contaminated by Cu and Cd, with light Pb pollution, and Zn pollution existed in Yangziling mineing area. From comprehensive heavy metal pollution index, Lala and Yangziling mining areas were severe pollution while moderate pollution in the Liwu mining area.(3)Owing to the natural selection in the three typical Western Sichuan copper mining areas, the natural colonized plants species are quite rich, the coverage of which was about 50%. But the natural colonized plants species in the Lala minging area is richer than Liwu and Yangziling mining areas, and the plant species in Liwu mining area is single, this is possibly because this mining area belongs to the the alpine gorge areas, which are steep slopes and large mountains, rock breakage and poor plant growth conditions.37 plant species from 16 families (mainly angiosperm) were investigated in this research.(4) The contents of heavy metal in the dominant plant of mining areas decleared that, the corresponding soil heavy metal content in mining areas is basically the same order:the centent of each element were:Cu>Zn>Pb>Cd. There was obvious positive correlation between contents of Cu and Zn (r=0.994**, P<0.01), Zn and Cd(r=0.539**, P<0.010) in plants shoot. There was obvious positive correlation between contents of Cu and Zn(r=0.590**, P<0.01), Pb and Zn(r=0.549**,P<0.01), Pb and Cd (r=0.582**, P<0.01), Cd and Zn(r=0.731**, P<0.01) in plants root.(5) Owing to the different ecotypes of plants from different mining areas, the accumulation, enrichment and migration coefficient of the Cu, Pb, Zn and Cd by plants were quite different. All the plant screened in this study did not reach the standards of hyperaccumulators, the standards, but Commelina communis, Polygonum capitatum Buc, Rumex hastatus, Pouzolzia sanguinea (Bl.) Merr thrived in mining areas and they could accommodate themselves to the high Cu, Pb, Zn and Cd contents, poor,drought environment, so they could be planted in the wasted lands for phytoremediation. And the Rumex hastatus had branched roots, high biomass, drought tolerance, and typical tolerance countermeasures. But the Commelina communis, Polygonum capitatum Buc, Pouzolzia sanguinea (Bl.) Merr and Memorialis hirta (Blume)Wedd were strongly glutinous and they could strongly accumulate the Cu, Pb and Zn, so they could be the suitable plants to restore the pollution in the slagheap and tailing dam.
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