Biological cycling of Koelreuteria paniculata plantation microelements in Xiangtan Manganese Mine wasteland Assessment of heavy metal pollutions in soils and bioaccumulation of heavy metals by plants in Rongxi Manganese mineland of Chongqing Evaluation on soil pollution in Pingle Manganese Mine of Guangxi using Vicia faba root-tip cells micronucleus testing Soil physical and chemical properties of the wasteland in Xiangtan manganese mine