Study On The Temporal And Spatial Evolution Of Urban Ecological Vulnerability Based On Community Scale

The coastal areas are densely populated with rapid economic development.As China's new urbanization process speeds up,the challenges faced by the ecological environment are increasing.As a typical coastal city,Dalian is characterized by undulating topography and mostly hills.During the process of high-speed urbanization,the type of land use in the city has undergone great changes.The area of construction land has increased dramatically.Green land such as forest land and grassland has been used.The area has gradually decreased,and the urban ecological environment is not optimistic.Jinzhou District is located in the northeast of Dalian City,bordering the Yellow Sea and West Bohai Sea to the east and the hinterland of Northeast China to the north.It is located in the Bohai Sea and the Northeast Asian Economic Circle.It enjoys a unique geographical location and “has the first development zone in China” – Dalian Economic and Technological Development.The district is known for its rapid economic development and rapid urbanization.It is a typical coastal open town.It is also the gateway to the northeastern hinterland of Dalian.It is the transition zone between Dalian and the Northeast economy and has a high research value.In the context of its rapid socio-economic development,the ecological problems it brings are on the increase.Correct understanding and evaluation of the ecological environmental vulnerability in Jinzhou District and the quantitative study of changes in human activities and the environment can provide a more in-depth understanding of changes in the regional ecological environment.And provide theoretical basis for the ecological protection of the study area.This paper takes RS and GIS as research methods,takes community as the research unit,comprehensively analyzes the basic characteristics of the ecological environment in Jinzhou District,and evaluates the ecologically fragile spatial and temporal dissimilarity in Jinzhou,and draws the following conclusions:(1)Based on the distribution characteristics of ecological vulnerability,the ecological vulnerability shows the trend of infiltration from coastal areas to inland areas.The vulnerability index shows that the central region is low,with the coastal waters in the east,the coastal and western parts of the northeast,and the coastal areas in the southwest.The trend of high ecological vulnerability index was very stable in the adjacent areas.(2)Analysing the ecological vulnerability of Jinzhou District on the basis of communities,it was concluded that the ecological vulnerability of communities in Jinzhou District is significantly different.The ecological vulnerability of communities near the coast has changed significantly,and the ecological environment has deteriorated seriously.The ecological vulnerability of communities far away from the sea has not changed significantly,and the ecological vulnerability index is relatively low.A relatively small part of the community showed negative growth in the value of EVI,and the ecological environment showed a trend of recovery.The number of micro-vulnerable communities decreased by 43 in 1998-2015,the number of vulnerable communities increased by 12,the number of moderately vulnerable communities increased by 32,the number of severely vulnerable communities decreased by 32,and the number of extremely vulnerable communities increased by 47 One.It can thus be seen that light vulnerabilities have dominated the period from 1998 to 2015,while the number of micro-fragile communities has decreased while the number of extremely vulnerable communities has increased significantly.(3)From the overall trend of ecological vulnerability of urban fringe areas,the average index of ecological vulnerability from 1998 to 2015 increased from 0.42 to 0.51,and the overall ecological vulnerability changed from slight to mild vulnerability to micro-The degree of vulnerability and extreme fragility coexist.The larger cv value in the central region of the study area indicates that the impact of seawater erosion on the central coastal area has a relatively large change in the vulnerability index,and the significance of ecological fragility gradually develops from coastal areas to inland areas.