Evaluation Of Urban Ecological Environment Vulnerability

In recent years,with the development of China’s social and economic level,various environmental problems have occurred frequently,such as severe soil erosion,land desertification,grassland degradation in many areas,and water pollution and biodiversity loss in many places;these environments Problems have always plagued people.The problem of ecological and environmental protection has become one of the primary considerations of people while vigorously promoting development.Therefore,the issue of ecological environmental vulnerability has become one of the hot topics that many scholars have studied.This paper describes the research status and progress of ecological vulnerability at home and abroad,and discusses the current research status of ecological environmental vulnerability assessment model,and the research ideas and research methods of this paper,combined with Nanchong City is located in the northeastern Sichuan hilly area The actual situation is based on the principle component analysis method to establish the evaluation index system of ecological environment vulnerability in Nanchong City.With the support of GIS,the evaluation model of ecological environmental vulnerability in Nanchong City was established,and the assessment of ecological environment vulnerability was conducted in Nanchong City.The temporal and spatial changes in the ecological vulnerability of Nanchong City from 2005 to 2015 were discussed.Through the research and analysis of this paper,the main results are as follows:(1)The indicator evaluation system in this paper fully considers the characteristics of the ecological environment of the Nanchong City in the study area,that is,the high degree of land use,the obvious change of the winter and summer monsoon,the large urban population,and the fact that the city is located in the hilly region of northeast Sichuan.The evaluation index system selected elevation,slope,vegetation cover,air temperature,precipitation,GDP,population density,land use as evaluation index influence factors,and used principal component analysis to assign weights to each index factor,and to establish an evaluation model.Ecological vulnerability assessment in the study area(2)From the final result to the ranking of ecological environmental vulnerability of Nanchong City,the proportion of mild and vulnerable areas was the largest in the study area in 2015,followed by potentially vulnerable and moderately fragile.Once again,it was severely fragile and the proportion of extreme fragility was minimal,but it still exists..In 2015,Nanchong City accounted for 4.35% of the area with severely vulnerable areas,while the extremely fragile proportion accounted for only 2.7%,the area with the most vulnerable areas was 49.95%,the moderately vulnerable area was 27.07%,and the potential vulnerability area was also 16.46%.The total potential of vulnerable and minor vulnerable areas in the study area reached 66.41%.From this it can be concluded that the overall ecological environment of Nanchong City in 2015 is still at a medium level.According to the index factor weight coefficients obtained from the principal component analysis,it is known that the evaluation index of land use has the largest ecological environmental vulnerability assessment in Nanchong City,followed by the vegetation coverage impact on the research area,and the per capita GDP and population density also have great influences.Therefore,the main factors affecting the ecological environment of Nanchong City are still human activities and socio-economic factors.(3)According to the socio-economic statistics of Nanchong City in 2005 and 2015,the dynamic analysis of the vulnerability of the ecological environment in Nanchong using the assessment model established by Arcgis comprehensively shows that during the ten years,the ecological environment vulnerability of Nanchong City is basically stable at a medium level.However,the moderately-vulnerable area has increased more than in 2005.The typical area is Xichong County,which was transformed from most of the original mildly vulnerable to moderately fragile.The relevant departments in these areas can be given a certain amount of attention,while focusing on economic development,Sexual protection of the ecological environment,such as vigorous planting of vegetation in Xichong County wasteland in order to maintain water and soil.Moreover,the environment in the entire study area has deteriorated or deteriorated in a very small number of regions.