Research On Spatial Distribution Of Park Green Space In Chengdu City Center Based On GIS And FRAGSTATS

With the continuous development of the society,the urbanization process of Chengdu has been accelerated in recent years.The central urban area has changed from 50 percent to11 areas,and the relationship between the city and the environment has become increasingly tense.Therefore,as an important role in urban development,urban park green space plays a crucial role in balancing the relationship between city and environment.At present,Chengdu pays more and more attention to the construction of urban park green space.General secretary Xi Jinping came to Chengdu for inspection and put forward the concept of building a park city.So it is necessary to study the space layout of park green space in Chengdu,which is the birthplace of the concept“park city”.This thesis regards the park green space(area)in the center of Chengdu city as the main research object,through field investigation and relevant data collection and qualitative analysis,and based on GIS and FRAGSTSATS software technology of quantitative analysis,and from the structure,spatial distribution,shape characteristics,distribution and degree of spatial connection pattern,and the residential land space relation,the five aspects to the center of Chengdu city park green space layout characteristics are studied,the main results were as follows:First,according to the classification of park green space patches,the park green areas in downtown Chengdu are mainly medium-sized small plaques and large plaques,accounting for 30.71%and 23%respectively.According to the type of park green space,it is mainly dominated by special parks and comprehensive parks,accounting for 46.19%and21.08%respectively.According to the administrative area of the park green space,it is mainly concentrated in the five old towns of Qingyang,Jinniu,Jinjiang,Wuhou and Chenghua,accounting for 12.11%,12.11%,14.80%,12.11%,12.11%and 13%respectively.Second,the park green space in the Third Ring Road is more concentrated,and the park green space outside the Third Ring Road is more scattered.The larger park green space is mainly concentrated in the third to fourth ring and the outer ring of the fourth ring,accounting for 56.07%,while the smaller park green space is mainly concentrated in the third ring,accounting for 43.93%,the closer to the city center,the road network layer park The smaller the area of the green space,the larger the area of the park green space in the road network layer that deviates from the city center.Third,the fractal dimension of the park green space plaque is low,and the difference is not between 1.01-1.34.However,the closer to the center of the city,the greater the impact of human factors,the greater the degree of fragmentation,and the fractal dimension index is between 1.21-1.34,so the shape complexity is relatively larger.Fourth,the nearest neighbor ratio is 0.630209,the nearest neighbor index is less than1,and the probability of belonging to the random distribution pattern is less than 1%.The layout pattern of the park green space in downtown Chengdu is clustering,but the degree of clustering distribution Not obvious.The park green space is mainly concentrated in the central area of the city.The closer to the center of the city,the greater the density of the park green space.The farther away from the city center,the lower the density of the park green space.Fifth,the parks in most residential areas have good accessibility,with good accessibility and good accounting for 39.73%and 30.62%,and only 29.65%of residential land accessibility is poor.The area of residential land that is not within the park green space service is 7948.91hm~2,accounting for 31.71%of the total area,while the park green space accessibility and good area account for 48.04%.Although the park green area service area already covers most of the residential areas,31.71%of the area in the central urban area is still a blind spot outside the park green space service area.Through the analysis of the above research results,the author draws a conclusion of the various factors that influence Chengdu city center park green space layout,and find the existing problems of the center of Chengdu city park green space distribution,according to the corresponding corresponding optimization strategy is proposed,in the adjustment of the Chengdu city park green space system planning for the future and prepare to provide some feasible ideas.