Chemical forms of heavy metals in the soils and plants of copper tailings yard Dynamics of nitrogen and phosphorus concentrations and nitrate reductase and acidic phosphatase activities in Imperata cylindrica on copper mine tailings Heavy metals accumulation in different parts of Paeonia ostii and soils at copper tailings yard Patterns of Vegetation Succession in the Process of Ecological Restoration on the Deserted Land of Shizishan Copper Tailings in Tongling City Characters of soil seed bank in copper tailings and its adjacent habitat Effect of chicken manure-amended copper mine tailings on growth of three leguminous species, soil microbial biomass and enzyme activities