Research On The Ecological Vulnerability Of Qianxinan Prefecture Based On The PSR Model

Strengthening the comprehensive improvement of karst areas in Southwest China is an important part of my country’s ecological civilization construction.Southwest Guizhou Autonomous Prefecture is located in a karst area in southwest China,with broken landforms,large undulations,thin and barren soils,and heavy rocky desertification in Guizhou,with serious soil erosion and relatively backward economic development.Carrying out ecological vulnerability research can provide a basis for ecological environment management in Southwest Guizhou Autonomous Prefecture,and has certain reference significance for the construction of ecological civilization and the promotion of rural revitalization.At present,there are few researches on the ecological vulnerability of Southwest Guizhou Autonomous Prefecture,so based on the integration of existing research at home and abroad,research on the ecological vulnerability of Southwest Guizhou Autonomous Prefecture is carried out.The aim is to explore the vulnerability state of the ecological environment in Southwest Guizhou Autonomous Prefecture,so as to provide a scientific basis for ecological environment management and regional sustainable development,as well as to provide assistance to promote the construction of ecological civilization and achieve the goal of rural revitalization.The research uses remote sensing and geographic information system technology,based on the PSR evaluation model to select 14 indicators from human activities,meteorology and hydrology,geology and landforms,land cover,environment and economic development,etc.,to construct an ecological vulnerability evaluation system.The study uses the ecological vulnerability index（EVI）model to study the status of ecological vulnerability from 2000 to 2018,and analyze the characteristics of temporal and spatial distribution pattern and change characteristics of ecological vulnerability in Southwest Guizhou Autonomous Prefecture.And through principal component analysis to discuss the driving force of the temporal and spatial changes of ecological vulnerability in Southwest Guizhou Autonomous Prefecture.Finally,put forward countermeasures for ecological environment management based on the evaluation results.The main research conclusions are as follows:（1）In terms of spatial distribution,the EVI of Southwest Guizhou Autonomous Prefecture is higher in the eastern part than in other regions,lower in the central part as a whole,and higher in the urban construction land and cultivated land in the southwest;the overall geographic center of ecological vulnerability is concentrated in the southern region,and the offset distance of the geographic center of gravity is small,indicating that the spatial distribution of the EVI has not changed much.In terms of the offset distance of the geographic center of gravity in different regions,the north is larger than other regions,followed by the south,and the east is the smallest.In terms of time changes,the EVI has a clear downward trend,showing a rapid decline in the early period（2000-2009）and gradually stable in the later period（2009-2018）.At the same time,the ecological vulnerability synthetic index dropped from 3.66 in 2000 to 0.12 in 2018,indicating that the ecological environment has been greatly improved and the ecological environment’s anti-disturbance ability has been enhanced.（2）According to the analysis of changes in ecological vulnerability grades,the ecological vulnerability of Southwest Guizhou Autonomous Prefecture has declined significantly.In 2000,Southwest Guizhou Autonomous Prefecture was generally moderately vulnerable and severely vulnerable.In 2009 and 2018,there was no severe vulnerability or above,and the overall vulnerability was mildly vulnerable.In addition,according to the analysis of the transfer of ecological vulnerability grades in different time periods,it is found that from 2000 to 2009,a large area of moderate and above vulnerability grades turned into mild vulnerability;while from 2009 to 2018,the ecological environment deteriorated slightly,and some were mild vulnerability turns into moderate vulnerability,and potential vulnerability turns to mild vulnerability.（3）Through principal component analysis in SPSS,it is concluded that there are four main driving forces that lead to the ecological vulnerability of Southwest Guizhou Autonomous Prefecture,which are land use status,socio-economic status,topography and landform status,and climate status.However,the driving forces in different years are different.In 2000,the driving forces of ecological vulnerability in Southwest Guizhou Autonomous Prefecture were land use status,socio-economic status,topography and landform status,and the contribution rates were 31.14%,30.42%and 23.967%in turn;in 2009,the driving forces of ecological vulnerability of Southwest Guizhou Autonomous Prefecture were socio-economic status,land use status,climate status,and topography and landform status,with the contribution rates being 30.47%,22.25%,19.84%and 16.99%in turn;in 2018,the driving forces of ecological vulnerability in Southwest Guizhou Autonomous Prefecture were land use status,socio-economic status,topography and landform status,and climate status.The contribution rates were 32.58%,28.57%,15.74%and 13.81%in order.In addition,according to the analysis of the correlation between the evaluation indicators and the driving forces,it is found that the ecological vulnerability of Southwest Guizhou Autonomous Prefecture is greatly affected by the changes in the area of green land and bare land.（4）According to the distribution characteristics of the ecological vulnerability of the counties and cities in 2018,the 8 counties and cities are divided into mildly vulnerable areas and moderately vulnerable areas.The mildly vulnerability areas have strong ecological environment stability and significant ecological governance effects,where involved counties and cities were Ceheng County,Xingyi City,Anlong County,and Xingren County,Qinglong County,and Pu’an County.The ecological environment in the moderately vulnerability area has weak resistance to external disturbance,serious soil erosion,and relatively backward economic development,where involved counties were Wangmo County and Zhenfeng County.（5）Combining the driving forces of ecological vulnerability and the results of zoning,the following ecological environmental governance countermeasures are proposed:the combination of ecological environmental governance and top-level design of regional rural revitalization;scientific planning and regional governance;optimizing industrial development structure and transforming economic development mode;improving population quality and promoting ecological civilization construction;raise funds for ecological governance through multiple channels,strengthen infrastructure construction;establish a long-term governance mechanism,and implement dynamic monitoring of the regional ecological environment..