Response Mechanism Of Ecosystem Services To Urban Land Expansion

Ecological security has become an important cornerstone of the national security system,an important research area in security science and engineering,and ecosystem services have an important impact on ecological security.At present,the expansion of urban land use in China is intensifying,and urban land takes up a lot of ecological land,resulting in the continuous decline in the level of ecosystem services,which seriously threatens regional ecological security.Therefore,the study of exploring the response mechanism of ecosystem services to urban land expansion,can reduce the damage of urban land expansion to ecosystem services and provide a theoretical basis for territorial space planning.This paper takes Wuhan City as the research object,and uses the equivalent factor method to calculate the ecosystem service value of Wuhan City.It analyzes the spatialtemporal change of urban land and the ecosystem service value.Further exploratory spatial data analysis and linear regression analysis were used to qualitatively and quantitatively analyze the spatiotemporal characteristics of Wuhan urban land expansion on ecosystem service value.Finally,used the FLUS model to simulate the expansion of urban land in Wuhan,and built the best expansion plan.The study founded:(1)During the period of 1990-2015 in Wuhan,the value of various ecosystem services continued to decline.In terms of space,the value of ecosystem services in the central region where urban land is concentrated has dropped sharply.(2)The urban land expansion area has the highest impact on ecosystem services;the expansion elevation has a moderate impact;the expansion distance has a lower impact;and the expansion slope has the lowest impact.(3)The total value of ecosystem services weighing the urban development inertia and the ecological security expansion plan is higher than the simulation plan based on the urban development inertia,of which only the food supply and soil retention values are slightly lower than the simulation plan based on the urban development inertia.The main conclusions are obtained through analysis:(1)The expansion of urban land in Wuhan is the main reason for the decline in regional ecological security.The expansion of urban land has caused serious damage to food supply and hydrological regulation.(2)Wuhan urban land expansion can protect food supply and soil retention by reducing the gradient of urban land expansion;increase urban land expansion elevation to protect hydrological regulation,waste treatment,maintain biodiversity and aesthetic landscape;increase urban land expansion distance to protect Gases regulate and maintain biodiversity.(3)Weighing the urban development inertia and the ecological security expansion plan in exchange for the loss of trace food supply capacity and soil retention capacity in exchange for the protection of the remaining ecosystem service functions.The urban land expansion plan has the lowest impact on regional ecological security on the basis of meeting urban development.