Succession law and model of reclaimed soil quality of opencast coal mine dump in grassland

Soil quality change is to measure soil productivity level and soil environmental quality. The dynamic succession law of Inner Mongolia mining waste dump reclaimed soil quality (Soil bulk density, Organic matter, Available P, Available K, Total N, Alkali Hydrolysable N, pH value, Electrical Conductivity) were summarized through the typical residential survey in this paper, and soil succession model of the study area were constructed by using indexes sum method. Results showed that the Organic matter, Available P, Available K, Total N, Alkali Hydrolysable N content in study area soil increased and all the soil quality gradually closed to its content in original landform. Soil succession model using indexes sum method showed study area already improved soil quality status, and gradually closed to the original landform soil quality. This study provides the theoretical basis for land reclamation and ecological restoration in ecological fragile mining area of opencast dump.