Research On The Construction Of Ecological Security Pattern Based On Ecosystem Service Assessment

With the unprecedented rate of urbanization,human activities frequently interfere with the natural ecosystem,which has a significant impact on ecosystem services and threatens the sustainability of the ecosystem.Identifying and protecting ecosystem services is an important prerequisite for future sustainable development.Ecological security pattern focuses on the relationship between ecological processes and functions;moreover identifying and optimizing ecological security pattern is an effective measure to maintain ecosystem functions and ensure the sustainable development of region.Exibei region is one of the biodiversity hotspots in China,and it is also an important water source area for the Central Line Project of South-to-North Water Diversion.Therefore,the ecological security in Exibei region is of great significance to China.In this paper,Exibei region was taken as an example to evaluate the ecosystem services from 1990 to 2015 and construct the regional ecological security pattern using the results of the year 2015 based on multi-dimensional remote sensing data and socio-economic data.Firstly,ecosystem service value(ESV)was quantified based on land use data,and on this basis,the impact of supply and demand was considered to evaluate ecosystem service scarcity value(ESSV).Then,based on the evaluation results of ESV and ESSV,the key ecosystem services in Exibei region were selected,and the spatial panel model was employed to further quantify the spatial effect relationships between urbanization and ecosystem services.Finally,the minimum cumulative resistance model(MCR)was utilized to construct the ecological security pattern in the northwest of Hubei Province and the corresponding optimization strategies were proposed.The main research conclusions of the paper are as follows:(1)From 1990 to 2015,the Grain for Green Program(GGP)had a significant impact on land use in Exibei region.During the 25 years,the land use change was mainly the increase of water body and construction land,while the other land use types decreased.The land use changes directly led to the obvious change of ESV.During the study period,the ESV showed an upward trend on the whole.The ESV was mainly composed of regulating services,and the proportion of cultural service was the lowest.The ESV of regulating service,supporting service and cultural service increased from 1990 to 2015.In terms of space,the value of unit ESV was the highest in the area along the Han River.When considering the impact of scarcity of ecosystem services caused by supply and demand changes,the total ESV increased by 468.04%,among which,the ESSV of hydrological regulation,gas regulation and climate regulation was the highest.The ESSV of public goods ecosystem services has increased significantly.(2)The results indicated that excluding the food production mainly concentrated in the high HD area,the other three types of ecosystem services(i.e.,carbon sequestration and oxygen production,water retention and soil conservation)and total ecosystem services(TES)were mainly concentrated in the low HD area in the southwest.The global Moran's I index showed that TES,HD,GDP density and population density all had obvious positive spatial autocorrelation.According to LM test,Wald test,LR test and Hausman test,SDM model with spatial and temporal fixed effects was selected as the optimal model.The model results showed that there was a significant spatial spillover effect of TES.For every 1%increase of TES in surrounding towns,the local town TES will increase by 0.8460%.At the 1%significance level,HD has a significant negative correlation with TES,indicating that the increase of human disturbance leads to the degradation of ecosystem services.In contrast,the coefficients of other indicators of urbanization,namely GDP density and population density,were not as significant as HD,indicating that land urbanization was the dominant factor affecting ecosystem services.(3)The main land use types of ecological source were forestland,farmland and grassland,and forestland and farmland land were dominant,mainly concentrated in the northeast and southwest of the study area.Based on the minimum cumulative resistance model(MCR),the minimum cumulative resistance surface of the area was obtained,and the high resistance area was mainly around the construction land for human production and living.The area of low level ecological security area was mainly dominated,which decreased in the past 25 years.In all levels of ecological security,forestland accounted for the highest proportion.The number of 29 ecological corridors and 30 ecological nodes were identified to construct the ecological security pattern Exibei region.From the perspective of space,the study area was composed of one horizontal and three vertical ecological corridors connecting the scattered ecological sources through the ecological nodes.We suggested:in the formulation of sustainable development policies,more attention should be paid to land use types with higher potential ecosystem services.Ecological restoration projects should be continued to carry out,meanwhile,levels of management should be implemented in the source areas to improve the quality of ecosystem services from the source.Coordinating regional management measures for different levels of security and strengthening regional cooperation across administrative boundaries are essential for ecosystem management.The results can provide a scientific basis for decisions-makers formulate feasible policies for regional sustainable development.