Research On Land Ecological Security Pattern And Spatial Layout Optimization In Fuhe River Basin Based On Dominant Ecological Function

The rapid advancement of the urbanization process makes ecological environment and ecological security problems increasingly prominent,not only aggravating the contradiction between social ecology,natural ecology,and economic ecology but also having a great impact on the stability of regional ecosystems.Regional ecological security encounters unprecedented challenges.Fuhe River is one of the five tributaries of the Poyang Lake water system and is of great significance in providing multiple ecological functions and maintaining regional ecological security.However,with the rapid advancement of urbanization,the urban construction land in the river basin has been continued to expand,and many natural resources have been developed disorderly,resulting in a series of ecological and environmental problems.Taking the Fuhe River Basin as the study area,this study analyzed the water conservation,soil conservation,and biodiversity service capacity index in Fuhe River Basin from the perspective of dominant ecological functions,and based on the above results,this study analyzed the ecological security pattern of the land in the Fuhe River Basin according to the research framework of"determining the ecological source-constructing resistance surface-extracting corridors",and identified the key areas for ecological restoration,and finally determined the optimal spatial layout system of ecological security in the study area,which was of great significance for maintaining the ecological security in Fuhe River Basin and realizing ecological restoration of the national land space.The main conclusions of this study are as follows:(1)The total water connotation capacity in Fuhe River Basin was 4.49×10~8 mm,which showed a gradual increase from upstream to downstream spatially.The total soil conservation capacity in Fuhe River Basin was 3.20×10~9 t.It showed a spatial trend of increasing and then decreasing from upstream to downstream.The biodiversity maintenance index in Fuhe River Basin ranged from 0 to 0.2151,with a spatial trend of increasing and then decreasing from upstream to downstream.(2)There were 21 ecological source lands in Fuhe River Basin,with a total area of5282.28 km~2,accounting for 25.72%of the total area in Fuhe River Basin,mainly in the upstream area,and the land use type in the ecological source lands was mainly forest land;there were 45 ecological corridors in Fuhe River Basin,with a total length of 851.42 km,20corridors passing through rivers and lakes in Fuhe River Basin,and the ecological corridors were mainly distributed in the downstream area in Fuhe River Basin.From the distribution of corridors in each county,Linchuan District had the most ecological corridors and Zixi County had the least ecological corridors.(3)The key areas of ecological restoration in Fuhe River Basin were identified as follows:i.There were 34 ecological pinch points with a total length of 152.46 km,mainly in the downstream area in Fuhe River Basin.From the distribution of ecological pinch points in each county,Jinxian County had the most ecological pinch points and Qingshan Lake District had the least ecological pinch points.ii.The ecological barrier points were 154.25 km~2 in total and were mainly located in the downstream area in Fuhe River Basin.iii.There were 119 ecological fracture points,46 ecological corridors in the Fuhe River Basin intersect with highways,25 with national highways,34 with provincial highways and14 with railroads,and the ecological fracture points in the lower reaches in Fuhe River Basin were the most distributed.From the distribution of fracture points in each county and city,the fracture points were most distributed in Nancheng County,with 19 points,and least distributed in Lichuan County and Le’an County,with only 2 points.iv.The broken ecological space was 2120.07 km~2 in total,accounting for 10.32%of the total area in Fuhe River Basin,mainly in the middle reaches in Fuhe River Basin,and the area of the broken ecological space varies among different land use types,in descending order of woodland,grassland,water area.The key areas of typical restoration were extracted,and corresponding ecological protection and restoration measures were proposed for different key restoration areas.(4)The construction of the"three axes and six districts"ecological security spatial layout optimization system with the Fuhe River as the main axis.The"three axes"included Lishan-Luoshan-Xianguifeng-Cuiyunfeng ecological corridor,Dahua Mountain-Furong Mountain-Hongmen Lake-Qingliang Mountain Ecological Corridor,and the Yaohu-Baihuling-Fenggang River-Qinhu-Fuhe Source Ecological Corridor,which was mainly based on the Fuhe River.The"six zones"included the important ecological conservation area on the upstream west bank,the ecological conservation area on the upstream east bank,the key ecological control area on the midstream west bank,the ecological control and restoration area on the midstream east bank,the ecological restoration,the management area on the downstream west bank,and the ecological protection and restoration area on the downstream east bank.