Evaluation of Eco-Environmental Vulnerability Using RS and GIS: Case of Ma Keng Iron Mining Area in Fu Jian Province, China

摘要

Mining activities are always associated with disturbances and negative eco-environmental changes to the natural ecosystems due to vegetation clearing, soil and water quality degradation and air pollution. Makeng mining is the biggest iron mine in Eastern China. The area has undergone severe eco-environmental changes due increasing anthropogenic activities aiming at exploring the iron ore and other minerals. Mining activities are accompanied by other human activities which include roads and industries construction, clearing of vegetation, construction of workers houses, sedimentation ponds and tailing dams. Soil-water erosion is acute because of the vegetation cover removal and is worsened by the mountainous nature of the area. The aim of this research was to evaluate the eco-environmental vulnerability of Ma Keng mining area for the past 15 years using a numerical environmental evaluation model. Application of GIS and RS technology, assisted by statistical software (SPSS) enabled the extraction and preparation of eco-vulnerability factors and development of the environmental numeric model. This was eventually used to evaluate eco-environmental vulnerability of Ma Keng mining area. Nine eco-environmental vulnerability variables were included in the model namely slope, elevation, soil types, land use, vegetation types, industrial dust pollution, industrial sulfur dioxide gas (SO2) emission and soil erosion. An Eco-environmental Vulnerability Index (EVI) of the study area for the years 1992, 1998, 2001, 2004 and 2007 were calculated using the environmental numeric model and the results were classified using the cluster principle. The research results showed that the eco-environmental vulnerability integrated index (EVSI) was increasing with time from 1992-2007. The results further revealed that the eco-vulnerability degree is vertically distributed, whereby the low elevation regions are worse than those in higher elevations. To reverse the intensification of eco-vulnerability, improvement in implementation of voluntary and legal environmental protection measures and ecosystem approaches are required.