RS and GIS-based Assessment for Eco-environmental Sensitivity of the Three Gorges Reservoir Area of Chongqing

Four factors (soil erosion, rocky desertification, bio-inhabitation and acid deposition) are selected to establish the evaluation model of eco-environmental sensitivity by using the integrated approach of GIS and RS in the present study. This paper conducts an integrated research on the eco-environmental sensitivity and reveals its spatial features in a quantitative way. The results are shown as follows. (1) The strong, moderate and extreme sensitivities are the main types of soil erosion sensitivity. The northeastern part of the study area is the most sensitive area of soil erosion sensitivity. The proposed soil erosion sensitivities were found to be consistent with real soil erosion. (2) The proportion of insensitivity area dominates karst rocky desertification, followed by strong and moderate sensitivity. The northeastern and southern parts of the study area are the most sensitive area and the western-central part is not sensitive. The real karst rocky desertification accorded with karst rocky desertification sensitivity. (3) The insensitivity and strong sensitivity are the main types of the sensitivity of bio-inhabitation. The northeastern and southern parts of the study area are the most sensitive area. The bio-inhabitation sensitivities in the central and western parts of the study area are relatively low. (4) The area of strong sensitivity of acid deposition is the biggest, followed by moderate and slight sensitivities. The extremely sensitive areas spread fragmentarily. The moderate and strong sensitive areas are concentrated and present a massive distribution. The slight sensitive and insensitive areas of acid deposition are distributed along the rivers and streams in a belt-shaped pattern. (5) The slight sensitivity of integrated eco-environment sensitivity is the main type in the study area, the insensitivity and moderate sensitivity take a second place. The integrated eco-environment sensitivity in the northeastern and southern parts of the study area is high. The integrated eco-environment sensitivity in the central and western parts of the study area is low.