Construction And Optimization Of Ecological Security Pattern In Hancheng City From The Perspective Of Ecosystem Service Supply And Demand

Ecosystem service refers to the environmental conditions and effects that human beings depend on,which are composed of natural ecosystems.It has a crucial impact on ensuring human welfare,protecting ecological security and realizing sustainable development.With the rapid development of our social economy,human activities’intervention in natural ecosystem is more and more strong,which leads to the decline of regional ecosystem services gradually,but the demand for ecosystem services is increasing constantly,which leads to the problem of unbalanced supply and demand and mismatch becoming more and more prominent.Therefore,it is of great significance to establish a regional ecological security pattern based on the matching characteristics of ecosystem service supply and demand to ensure regional ecological security and improve human welfare.It is of great theoretical and practical value to study the supply-demand relationship of urban ecosystem services scientifically and to find the way to optimize the pattern of regional ecological security.In this paper,Hancheng City of Shaanxi Province was selected as the study area.In order to establish a regional ecological security pattern,ecological sources were identified from three aspects,including habitat quality,the importance of ecosystem services and landscape connectivity.At the same time,it is also necessary to identify areas with high demand for ecosystem services by combining land use degree,population density and per capita GDP.Next,the minimum cumulative resistance model can be used to extract the ecological corridors between the ecological sources and between the ecological sources and the areas with high ecological demand,so as to effectively identify and construct the regional ecological security pattern.On this basis,the ecological security optimization pattern of"two zones and six regions"is identified and optimization measures are proposed.The study says:(1)The areas with high habitat quality are mainly located in the central and western mountains and hills of Han City and the west bank of the Yellow River in the east.In the eastern part of the central region,the urban and industrial construction areas,the agricultural planting core areas and the traffic roads were affected by human activities,which led to the lower habitat quality.The overall importance of ecosystem services is"high in the west and low in the east".Landscape connectivity presents a spatial pattern of"high and low scattered",in which the areas with high connectivity are mainly distributed in the mountainous and hilly areas in the west of Han City,and the Yellow River and coastal areas in the east.The overall connectivity among patches is high,which is conducive to the habitat and migration of organisms.The central loess hilly area is lower.The spatial pattern of landscape connectivity is high in the east and low in the middle.The areas of high connectivity are mainly located in the mountainous and hilly areas in the west of Han City,and the Yellow River and coastal areas in the east.The overall connectivity among patches is high,which is conducive to the habitat and migration of organisms.The central loess hilly area is lower.(2)In the spatial pattern of ecological supply,the high ecological supply area is mainly located in the southwest and southwest corner of Hancheng City;The higher supply area is mainly located around the high supply area,including Sangshuping Town,Xizhuang Town,Banqiao Town and the middle of Zhiyang Town.The spatial distribution pattern of ecosystem service demand presents the characteristics of"high and low value clustering".There are two large areas of high value clustering.One is the high demand area of Xincheng Street and Jincheng Street in the west bank of the Yellow River,and the other is part of Longmen Town and Xizhuang Town in the northeast region.The demand for ecosystem services is relatively high.However,in the central and western parts of Xizhuang Town,Sangshuping Town,Banqiao Town,Zhiyang Town and other areas,due to relatively sparse population distribution,low land use degree,economic development is dominated by farming industry,and there is a lack of heavy industry enterprises that consume large resources,so the demand for ecosystem services presents a pattern of low value aggregation distribution.(3)The total ecological source area of Han City is 434.83km~2,accounting for 27.62%of the total area of Han City,which is concentrated in the northwest and southwest of Han City.There are 16 intersource ecological corridors in Han city,with a total length of254.24km.They are widely distributed and connected with various ecological sources,and are the main way for the exchange of ecological services between different sources and regions.Between the source area and the ecological demand area,there are six demand corridors with a total length of 126.81 km,which are distributed in the form of short branches and mainly connect to Xincheng Street,Jincheng Street,and the eastern part of Longmen Town,Xizhuang Town,Zhiyang Town and Zhichuan Town.Based on the spatial layout and ecological needs of various ecosystem services,ecological sources and ecological corridors in different regions,combined with landform features and from the perspective of ecological protection and urban construction,The ecological protection core area,key ecological construction area,key mine restoration area,central urban development area,soil conservation and improvement area,southern ecological agriculture area and ecological construction zone along the Yellow River.The Yellow River tributary water conservation protection belt"two belts".