A Coupling Method for Eco-Geological Environmental Safety Assessment in Mining Areas Using PCA and Catastrophe Theory

Most mineral resources in China are located in the areas with fragile geologic environment, where long-term irrational exploitation of mineral resources has caused serious eco-geological environment problems in mining areas as well as their surrounding areas. Hence, it is of great significance to carry out eco-geological environment security assessment for ecological environment protection of mining area. Nevertheless, up to now, effective methods were still quite rare in the field of eco-geological environment security assessment on mining areas. With a focus on the serious ecological environment and geological environment of the Panxi mining area in China, based on GIS and RS, an indicator system and a method with catastrophe theory and the principal component analysis were constructed for evaluating eco-geological environment security of the mining areas; then, validation was carried out for proving their efficiency. The results indicated that, considering natural and human factors, the method eliminated the correlation between various variables and was capable of evaluating the eco-geological environment security in mining areas quantitatively and objectively. Comparing to the existed methods, the proposed method overcame the shortages of the commonly used "index × weight" method, which causing the same contribution of the indicator in different periods for eco-geological environment security. Our method eliminated the "weight" influence on the result and was especially suitable for studying the long time series of the eco-geological environment security assessment and the analysis of driving factors. Besides, the status of the eco-geological environment security in the study area was mainly in safe or relatively safe. The distribution of mild and severe warning areas was limited. The distribution of unsafety areas was small but concentrated in the mining concentrated area within the study area.