Abstract:An investigation which includes microclimate,gangue physical and chemical properties,terrain,gangue moisture,and organism was carried out in 280 coal waste piles in Yangquan City,Shanxi Province.Microclimate of coal waste piles was hot and dry,and ground temperature was abnormal by spontaneous combustion of gangues.Temperature of sloping surfaces where partly had been burning was exceeded the normal temperature range for plant growth.Coal waste piles easily generated slope erosion due to their large slopes and lax accumulations.After surface gangues had been eroded,no soil adhered to plant roots and plant growth vigor gradually became weak.Compared with loess,gangues had poor water holding capacity and low available water capacity.Surface gangues lacked water supplements from lower layers,which affected plant growth directly.The pH value of ignited gangues declined,nutrient status of surface gangues was bad,and species and quantity of gangue microbe were small.Plant growth condition in the coal waste piles indicated that ground temperature,erosion condition,acid,and moisture were factors affecting vegetation restoration.Plants could not grow if ground temperature exceeded 50 ℃ or pH value was low than 5.Compared with the regions of 20% water moisture,vegetation coverage in the region of 15% water moisture declined by about 10%~20%.In the eroded areas,vegetation coverage declined by about 30%.