关键词: 三峡库区, ISODATA模糊聚类分析, 生态区划

Abstract:

As a significant symbol of regional ecological environment health, ecological security is an important component of social stability and national security. In this paper, a new index system was established for ecological security construction in the Three Gorges Reservoir area according to the local natural and economic conditions, and the principles, indices and methods for ecological security regionalization were discussed based on ecological theory. The whole Three Gorges Reservoir area was then divided into 4 regions with different degrees of ecological security, using fuzzy cluster analysis of ISODATA and the tools for analytic hierarchy process of SPSS. The characteristics of the 4 regions were analyzed, and the distribution map of them was drawn using ArcGIS. It is showed that there were about 2 852 thousand people, accounting for 17% of the total population of the area, living in regions with better situation of ecological security, occupying 15% of the total reservoir area; whereas, 57 percent of the total population living in regions of type III and IV with fragile environment, accounting for 55% of the total area. Soil erosion rates in these regions exceeded 4 600 t/km2〖DK1〗·a.Therefore, the situation of ecological security in the Three Gorges Reservoir area was serious. The results can be of reference significance for ecological security evaluation and the construction of ecological security in the reservoir area. It was also proposed that comprehensive management of hilly areas, controlling soil erosion and decreasing pollution are key points to improve the ecological situation of the Three Gorges Reservoir area.

Key words: hree Gorges Reservoir area, fuzzy cluster analysis of ISODATA, ecological regionalization