Study On The Construction Of Ecological Security Pattern In Lichuan City Based On The Minimum Cumulative Resistance Model

Lichuan City is Located in the western part of Hubei Province and the hinterland of Wuling Mountainous Area,the city belongs to the important area of biodiversity conservation and water conservation in Wuling Mountainous Area.With the accelerating process of urbanization,the contradiction between ecological protection and development and utilization in Lichuan City has become increasingly prominent.A series of ecological and environmental problems such as environmental pollution,soil erosion and rocky desertification have emerged,which has made the ecological security of Lichuan City highly concerned by the local government and the public.This paper takes the whole region of Lichuan as the research object.Based on the evaluation of the importance of the ecosystem,combined with the distribution of nature reserves in Lichuan,the important ecological sources in the ecological security pattern of Lichuan are determined.On this basis,the ecological resistance surface of Lichuan City was constructed.At the same time,the factor of geological conditions is introduced to characterize the contribution of karst landform to ecological resistance.Finally,the Minimum cumulative resistance model(MCR model)and gravity model are used to identify important ecological corridors.Combined with the distribution of important water systems and main mountains in Lichuan City,the ecological security pattern of Lichuan City is constructed.The main conclusions are as follows :(1)The importance level of ecosystem function in Lichuan City is relatively high.Among them,the area of ecosystem function importance above the higher level is about 2234 square kilometers,accounting for 52 % of the land area,mainly distributed in the eastern and southern regions of Lichuan City.The area of ecosystem function importance below the lower level is about 953 square kilometers,accounting for 21 % of the land area,mainly distributed in the northwest region of Lichuan City.(2)The overall ecosystem sensitivity level of Lichuan City is low,and 70 % of the city is located in areas with low ecosystem sensitivity.(3)The importance level of ecosystem in Lichuan is high.61 % of the city ’s61 % of the area belongs to the area above the higher level of ecosystem importance.Among them,the total area of the high level of ecosystem importance is 1819 square kilometers,accounting for 39 %.(4)Through the evaluation of ecosystem importance and the distribution of ecological protection areas in Lichuan City,five important ecological sources in the ecological security pattern of Lichuan City were identified.On this basis,15 important ecological corridors were identified by MCR model and gravity model.Combined with the distribution of important water systems and mountains in Lichuan City,the ecological security pattern of Lichuan City with the distribution characteristics of ’ three screens-two belts-three districts-five cores ’ was constructed.