Study On Optimization Strategy Of Green Space System In Central Changsha Based On Landscape Pattern Analysis

Under the background of rapid urbanization,construction land is constantly eroding urban ecological space.Different development intensities in changsha city lead to obvious differences in green space pattern among regions.A series of urban ecological environment problems have arised,and the relationship between green space,human settlements and sustainable coordinated development of cities has gradually attracted attention.Under the background of territorial space planning,higher standards and requirements are put forward for urban green space system planning,system optimization,function play and quality space construction.Our paper is based on the visual interpretation of sentry 2 Remote Sensing Image in 2020 to obtain the greenbelt database.Based on Arc GIS platform and landscape pattern theory,the urban green space system pattern of Changsha city center in 2020 was studied.The research contents are as follows:(1)Overall characteristics of green space landscape in the study areaAccording to patch fragmentation degree,the central urban green space system as a whole presents a pattern dominated by small patches.Attached green space and road green space accounted for the largest proportion in number,with relatively few large patches,scattered green space,less transition between green space and insufficient connectivity.The transition between green space and grey infrastructure is stiff and fragmented.The overall shape of green space is more regular.The boundary diversity and species richness of greenbelt are also relatively low.From the distribution of green space types: Firstly,the central part of the central city is mainly affiliated green space and road green space.Infrastructure,residential facilities and production facilities along the route shall be set up.There are few transition and continuity zones between patches,and the segmentation is obvious.Secondly,both sides of the Xiangjiang river belt green,hard pavement accounted for a large proportion.It has not formed a continuous,open ribbon parks,green corridors,greenway or protective green spaces.Finally,the southeast,southwest and northeast of the central city are mainly protected green Spaces,with a large area.Other types of green space are few and unevenly distributed.There are a large number of green parks in southwest China,but there are some problems such as single form,regular boundary shape and lack of regional characteristics.The northeast has less green land,mainly road green land;There are a small amount of protective green space,the least attached green spaces,park green spaces.The distribution of production green land in the central urban area is small,and most of them are independent patches.(2)Comparative analysis of green space landscape pattern in different districts and counties in the research areaFurong District is mainly the old city,the highest degree of fragmentation.Secondly,Tianxin and Yuhua District developed earlier,and were dominated by road green space and affiliated green space,with small patch area and large patch quantity.Due to the large degree of development,there is less green space for development in the region,such as less large park green space,limited development space of green space,low degree of patch aggregation and high degree of fragmentation in the region.The ecological benefits in these three regions are insufficient and the ecological stability is poor.The diversity index of green land in different districts and counties is low.Wangcheng District due to the late development,the degree of diversity is the lowest.Different districts and counties all have the problems of single green space type,regular shape and low diversity,and the distribution of green space is extremely uneven.From the point of view of aggregation degree,the aggregation degree of lotus,Tianxin and Yuhua Districts in six different districts and counties is low,while the aggregation degree of Wangcheng,Yuelu and Kaifu Districts is high.The areas with low aggregation degree are mainly the areas developed earlier in Changsha,which are quite different from the areas developed later.(3)Optimization strategy of green space system landscape pattern in the study areaBased on the principles of integrating green network system,enhancing the richness of green patches,conserving characteristic green patches,and improving the efficiency of green patch management,the optimization strategy of urban green space landscape pattern was proposed,including integrating park system,constructing distributed green space system,and creating linear open space system.Create a variety of corridor combination modes to strengthen the link between patches.Then,a regional,collaborative,networked and ecological regional green space network system is constructed,which is integrated and common with urban construction.