Study On Ecological Protection Red Line Demarcation In Gannan Tibetan Autonomous Prefecture

With the rapid development of urbanization in China,the contradiction between ecological environmental protection and social and economic development has become increasingly prominent.Gannan Tibetan Autonomous Prefecture is located on the Gannan plateau,and its ecological environment is fragile and sensitive.The evaluation and analysis of ecological sensitive areas based on natural factors and human interference factors are important for maintaining the regional ecological environment and ecological sustainable development.Considering the results of sensitivity evaluation,the GIS spatial analysis method and the principles of territorial spatial planning are applied to delineate the ecological protection red line in Gannan Tibetan Autonomous Prefecture,with a view to providing scientific reference for maintaining the ecological environment of the study area and delineating the main ecological function areas.By referring to the research results of many experts and scholars at home and abroad,combined with the environmental status of Gannan Tibetan Autonomous Prefecture,this paper analyzed the ecological sensitivity of the study area from five aspects:land desertification,soil erosion,climate environment,human disturbance and biodiversity by using the data of soil,precipitation,accumulated temperature,population,land cover and livestock carrying capacity.Using grid coding and spatial autocorrelation analysis,the spatial and temporal variation characteristics and regional differences of ecological sensitivity in Gannan Prefecture were discussed.Using NPP,annual precipitation,average annual temperature,slope and soil data,we evaluated the service functions of soil and water conservation,water conservation and biodiversity in the study area,and analyzed their temporal and spatial distribution characteristics.By using overlay analysis and combining the evaluation results of ecological sensitivity and ecosystem service function,the ecological protection red line of the study area was delimited.The final findings show that:(1)In Gannan Tibetan Autonomous Prefecture,mild sensitivity was dominant,and the average area of youth sensitivity accounted for the largest proportion of the total area from 2000 to 2020,with the proportion of 33.37%.In the past 20 years,the mild and moderate ecological sensitivity of the study area showed a decreasing trend,while the areas of the insensitive and extremely sensitive areas showed an increasing trend.From the perspective of spatial distribution,the ecological sensitivity of the study area showed a decreasing trend from north to south and west to east,and the spatial agglomeration effect was significant.The areas with high sensitivity are mainly distributed in Xiahe County and Lintan County in the north of Gannan Tibetan Autonomous Prefecture.The less sensitive areas are mainly distributed in Maqu County and Zhouqu County in the south.(2)The red line of ecological sensitivity is dominated by the red line of climate and environment sensitivity.The total area of sensitive ecological protection red line in the study area is 8,004.30 km~2,accounting for 21.76%of the total area of Gannan Tibetan Autonomous Prefecture.The area of climate and environment sensitivity red line is6427.80 km~2,accounting for 57.66%of the total area of sensitivity red line.The area of human interference sensitive red line is 1475.12 km~2,accounting for 13.23%of the total area of sensitive red line.The area of the red line of soil erosion sensitivity is 321.43km~2,which only accounts for 2.88%of the area of the sensitivities-red line.The sensitive red line area of land desertification is 2894.62 km~2,accounting for 25.96%of the total sensitive red line area.The area of the red line of biodiversity sensitivity was 29.51 km~2,and its area proportion was 0.26%.(3)The red line of ecosystem service function is mainly red line of soil and water conservation service function.The total area of service function ecological protection red line is 8715.90 km~2,accounting for 23.70%of the total area of Gannan Tibetan Autonomous Prefecture.The red line area of soil and water conservation service function is 7250.48 km~2,accounting for 62.50%of the total area of the red line area of service function.The area of water conservation service function red line is 2848.25km~2,accounting for 24.55%of the total area of service function red line.The red line area of biodiversity service function is 1502.82 km~2,which only accounts for 12.95%of the red line area of service function.(4)The red line area of ecological protection in Gannan Tibetan Autonomous Prefecture is 23350.30 km~2,which is mainly located in Maqu County in the southwest of the study area,Xiahe County,Hehe City and Lintan County in the north,central Zhuoni County and Zhouqu County and Dibe County in the southeast of the study area.