Analysis of Grassland Desertification Due to Coal Mining Based on Remote Sensing——An Example from Huolinhe Open-cast Coalmine

Impacts of coal exploitation on grassland are grassland destruction and desertification.In this paper,the desertified grassland in Huolinhe open-cast coalmine was extracted from remote sensing imagey by using decision tree and back-propagation(BP) neural network,and the desertification during the past 16 years in the study area was analyzed.The results indicate that ① from 1987 to 2003,there is a strong to weak,then weak to strong evolution process for the total grassland desertification,which can be attributed to climate change and human activities,especially to the influence of climate change;② there is a evolution similar rocess from strong to weak,then from weak to strong for the area of medium desertification and slight desertification,which can be mainly ascribed to the climate changes,then to the over-grazing,uprooting of the medicinal materials,and over-reclamation;③ due to the coal exploitation,the severe desertification is always in shape of ▲ around the mining land,and developed to the east quickly with the help of monsoon;④ the area of severe grassland desertification is on the increase during the past 16 years,and there is much correlation between the mining land and severe grassland desertification area,so the mining land area can be served as an important indicator for coalfield eco-environment assessment and prediction.