Combining AHP with GIS in synthetic evaluation of eco-environment quality—A case study of Hunan Province, China

The analytic hierarchy process (AHP) has the special advantage in multi-indexes evaluation, and geographical information system (GIS) is good at spatial analysis. Combining AHP with GIS provides an effective means for studies of regional eco-environmental evaluation. Aiming at the regional features of eco-environment and main environmental problems of Hunan Province, the synthetic evaluation index system was set up including natural environment, disaster, environment pollution and social economy factors. Supported by GIS, taking the county as the evaluation unit, the regional eco-environmental information system database and evaluated the eco-environmental quality of Hunan Province were established. Based on the database and evaluation system, AHP, eco-environmental evaluation index method and spatial analysis were integrated into the eco-environmental quality evaluation in the study area. The results showed that 35.2% of the total land area in Hunan Province (approximately 68 462.45 km2) maintains a good or better grade of the eco-environmental equality. However, 22.8% of the total area (approximately 44 345.00 km2) was of a bad or worse grade of eco-environment quality. From the spatial distribution, the eco-environmental quality gradually decreased from the east to the west with exception in a few areas, which presented the obvious speciality of terrain. It was concluded that the current status of the integral eco-environment quality of Hunan Province was in the middle level, and highly intense human activities speeded up the degradation of regional eco-environments in recent years.