Abstract: Ecological sensitivity assessment, an important method to study the potential problems of regional ecology, plays an important role in regional ecological planning and management. In this study, we selected seven sensitive factors from the aspects of natural ecology, city expansion and ecological services, and established level index system of sensitive factors. We assessed ecological sensitivity of single factors and comprehensive factors using the analytic hierarchy process (AHP) under GIS platform. The results showed that: (1) From 1997 to 2007, the proportion of zones with nonsensitivity or low sensitivity increased by 3.91%, the proportion of moderate sensitive zone decreased by 0.57%, and the proportion of extreme sensitivity zone and high sensitivity zone decreased by 3.31%, indicating an overall reduction in ecological sensitivity. (2) From 2007 to 2017, the proportion of zones with nonsensitivity or low sensitivity increased by 2.38%, the proportion of moderate sensitivity area decreased by 3.71%, and the proportion of extreme sensitivity zone and high sensitivity zone increased by 1.32%, indicating an overall declining trend of ecological sensitivity. (3) High sensitivity areas were mainly distributed in woodlands and nature reserves in Zhaoqing, Huizhou, and Jiangmen. Ecosystems in these areas were vulnerable to disturbance, so protection should be strengthened. Low sensitivity areas were mainly distributed in Guangzhou, Shenzhen, Foshan and other central cities where ecosystems had good stability. These ecosystems can be reasonably exploited and utilized when their safety is guaranteed. Our results provide scientific basis for green sustainable development and environmental management in the Guangdong Hong KongMacao Greater Bay Area.

Key words: Stipa breviflora, fractal dimension., desert steppe, semi-variance function