1 Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment, Nanjing 210042, China.
2 Engineering Research Center of Ministry of Education for Mine Ecological Restoration, China University of Mining and Technology, Xuzhou 221116, China.
3 Nanjing University of Information Science & Technology, Nanjing 210044, China.
4 School of Metallurgy and Environment, Central South University, Changsha 410083, China.