Combining AHP with GIS for Evaluating Environmental Carrying Capacity in Shaanxi 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 environmental carrying capacity (ECC) evaluation. Aiming at the regional features of ecosystem of Shaanxi Province, the synthetic evaluation index system is set up including eco-elastic force, resource carrying capacity and environment carrying capacity factors. Supported by GIS, taking the city as the evaluation unit, the information system database of ECC of Shaanxi Province is established. Based on the database and evaluation system, AHP, ECC evaluation index method and spatial analysis are integrated into the ECC evaluation in the study area. The results showed that only 23% of the total land area in Shaanxi Province maintains a good or better grade of the ECC. However, 50% of the total area is of a bad or worse grade of ECC. From the spatial distribution, the ECC gradually decreased from the south to the north with exception in a few areas, which presented the obvious characteristics of terrain. It is concluded that the current status of the integral ECC of Shaanxi Province is in the bad level, and highly intense human activities speeded up the degradation of regional ecosystem in recent years.