Abstract: Taking Xinghua city, Jiangsu province as an example, this study explores the impact of the reforestation project on regional ecological sensitivity. Based on the analytic hierarchy process (AHP), the weight of each evaluation factor is determined by Delphi method, and the ecological sensitivity of Xinghua city is analyzed by single factor and multiple factor superposition. The results showes as follows: ①The mean values of regional comprehensive ecological sensitivity are 2.37 and 2.43, and the standard deviations are 1.18 and 1.28, respectively. The ecological sensitivity is increased, and the spatial distribution of each sensitivity level is more discrete. ②The receding lake has a greater impact on the sensitivity of buffer area, land use and vegetation coverage, but a lesser impact on the sensitivity of elevation, slope and aspect of slope,which is related to the characteristics of the plain water network in the Lixia River area. ③The weights of influencing factors for the comprehensive ecological sensitivity of Xinghua city are as follows: The spatial distribution of land type, vegetation index, water area buffer, elevation, slope and slope direction were similar to the first three indexes, showing that northwest is higher than southeast and suburban was higher than urban. This study can provide scientific guidance for the planning and ecological evaluation of returning polder to lake.

Key words: returning polder to lake, ecological sensivitity, AHP, transition matrix