Environmental quality characteristics and spatial division of Ningxia mines

Mines environment quality spatial distribution is important to government，which can provide the basis to repair and manage the mines environment of 22 counties in Ningxia province of China.Mines environment comprehensive evaluation index system was been built，include land use，geologic damage，environment pollution，water loss and soil erosion，and 16 indexs.The data was gotten by remote sensing data and mines environment statistics.Entropy weight fuzzy comprehensive method was used to evaluate the mines environmental quality，and then fuzzy clustering method by spss22.0 was used to divide the spatial partitions of mines environmental quality in Ningxia，and combined with field reconnaissance to determine result.The results show that the mines environmental quality in 22 counties is very differences.The northern part of Ningxia is generally better than the southern mountain area，but some of northern counties in Ningxia are worst.The mines environmental quality variation of 22 counties are relatively stable，and the main environmental problems are in the northern part of the old mining area of Huinong and Dawukou county，emerging mining area of Lingwu city and middle part of Ningxia i.e.Shapotou county.Then，Ningxia mines can be divided into four categories：“serious area，more serious area，general area，good area”.The distribution of mines environmental quality partitions is continuous from the province scale，but it concentrates from the counties scale.It should pay attention to the mining progress of the emerging mines，and continuously monitor on the mines environment，so as to early discovery and early management.The thresholds of categories by means of cluster analysis are discontinuity.It should increase the sample of cases，to find the threshold distribution of entropy weight fuzzy comprehensive evaluation value，so as to realize the continuous grading.