Based On The Study Of Geological Disaster Zoning And Ecological Sensitivity In The Eastern Mountainous Areas Of Landsat-8 Jilin Province

Geological disasters are more developed in the eastern mountainous area of Jilin Province,and the ecological environment is more complex.The frequent sliding current disasters and the sensitive and fragile ecological environment have seriously affected the suitability of the local environment and the prosperity and development of the economy and society.In this study,according to the characteristics of land disaster development in the eastern mountainous areas,indexes were selected for the analysis of land disaster zone.On the basis of land disaster assessment,15 indexes including geological disaster system,habitat system,social development system and soil system were selected from the perspective of harmonious development between man and nature to carry out ecological sensitivity assessment.Compared with traditional ecological studies,the ecological sensitivity evaluation in this study takes more consideration to establish ecological corridors and security patterns by identifying areas with high sensitivity,so as to provide beneficial references for ecological development and ecological economic prosperity in the eastern mountainous areas of Jilin Province.Specific achievements are as follows:(1)Based on landsat-8 remote sensing satellite image data,the water area in the study area was extracted and made into a buffer.The NDVI index and SWCI index were calculated and the pixel dichotomy principle was used to estimate the vegetation coverage and surface water content.NDBI index was calculated to reflect the exposure degree,building density and land use damage.Inversion of surface temperature is carried out to obtain the surface temperature distribution in the study area.(2)Comprehensively analyze the general situation of the study area and the general characteristics of geological disasters according to the existing geological disaster data.(3)analyze the relationship between geological disasters and five influencing factors,such as landform,rock type,annual average rainfall,vegetation coverage rate and human engineering activities,and carry out correlation analysis.(4)Regionalization analysis of geological disasters in eastern mountainous areas of Jilin ProvinceEight factor indexes(elevation,slope,topographic elevation difference,stratigraphic lithology,vegetation coverage rate,average annual rainfall,road buffer zone and human density)from three aspects of geological topography,natural environment and human activities were selected by Delphi expert consultation method to construct an evaluation system of geological disaster susceptibility in mountainous areas of eastern Jilin Province.The overall susceptibility of human density is non-susceptibility;The overall susceptibility of elevation,slope,topographic elevation difference,stratigraphic lithology and vegetation coverage rate is low.The overall susceptibility of average annual rainfall is highly prone.The overall susceptibility of road network distance is extremely prone.The vulnerability of comprehensive geological disasters can be divided into five levels: extreme vulnerability,high vulnerability,moderate vulnerability,low vulnerability and no vulnerability.The overall vulnerability of comprehensive geological disasters belongs to medium and high vulnerability.According to the susceptibility of geological disasters,key control areas,sub-key control areas and general control areas are established,and the results of geological disaster zoning obtained by previous studies are compared.(5)Ecological sensitivity analysis of mountainous areas in eastern Jilin ProvinceThe Delphi expert consultation method was used to select 15 factor indexes(ground disaster evaluation results,disaster history,water area,EI,slope direction,surface moisture content,surface temperature,land use,NDBI,population density,GDP,road traffic,soil type,soil erosion and soil PH)from four aspects: geological hazard system,habitat system,social development system and soil system)to construct an ecological sensitivity evaluation system for mountainous areas in eastern Jilin Province in 2000,2010 and 2020 respectively.The overall ecological sensitivity of disaster history,road traffic and soil erosion is not sensitive.The overall ecological sensitivity of land surface temperature,soil ph and soil type were all low sensitivity.The overall ecological sensitivity of slope aspect and comprehensive disaster assessment are highly sensitive.The overall ecological sensitivity of water buffer,ecological environment status index(EI),surface water content,land use,building land index(NDBI),population density and gross regional product(GDP)are extremely sensitive.Comprehensive ecological sensitivity can be divided into five levels: extremely sensitive,highly sensitive,moderate sensitive,low sensitive and insensitive.The overall integrated ecological sensitivity in 2000,2010 and 2020 belonged to low sensitivity,medium sensitivity and high sensitivity respectively.Based on the comprehensive evaluation results of ecological sensitivity in 2020,ecological source areas are extracted,ecological resistance surfaces are constructed,ecological corridors are identified,and an ecological security pattern of "one corridor and three circles" is finally formed.