Study On Dynamic Change And Ecological Sensitivity Of Land Use In The Middle And Upper Reaches Of Fujiang River

Ecological land plays an important role in adjusting regional climate and maintaining the stability of urban ecological environment.However,due to the continuous development of urban economy and the increase of urban scale,the area of urban construction land is gradually rising.The gradual expansion of urban construction land leads to the gradual reduction of the area of ecological land,resulting in the damage of regional ecological environment.Ecological sensitivity reflects the disturbance degree of human activities to the ecological environment.Ecological sensitivity is an important index to measure the fragility of regional ecological environment and plays an important guiding role in regional planning and development.Therefore,to study the relationship between land use and ecological sensitivity and to formulate a reasonable ecological function zoning is an important measure for the healthy development of city and ecological environment.This paper takes the middle and upper reaches of Fujiang River as the research area and constructs the basic framework of the relationship between land use and ecological environment.With the help of ENVI and GIS platform,the land use degree,land use dynamic attitude and land use type transfer in the middle and upper reaches of Fujiang River in 2000,2010 and 2020 were analyzed rationally.Combined with land use transformation,qualitative and quantitative evaluation of ecological sensitivity of land resources in the middle and upper reaches of The Fujiang River was carried out,so as to carry out a reasonable ecological function regionalization of the region,and the following conclusions were drawn:(1)From 2000 to 2020,the dynamic change of land use in the middle and upper Reaches of Fujiang River is as follows: the area of cultivated land and grassland in the region decreases significantly,while the area of construction land,forest land and water land increases significantly,and the fluctuation range of unused land is not large.In the dynamic change of land use in the middle and upper reaches of Fujiang River,the single dynamic attitude of construction land has been increasing steadily from 2000 to 2020.The dynamic attitude of unutilized land in Fucheng District,Youxian District and Jiangyou City showed a negative growth trend,and the dynamic attitude of construction land area kept a positive growth from 2000 to 2020.The fluctuation range of cultivated land,forest land and grassland is not big.The dynamic attitude of comprehensive land use in the middle and upper reaches of Fujiang River is basically in a stable trend,and the dynamic attitude of comprehensive land use in the districts and counties under the jurisdiction of Fujiang River is stable.(2)Based on the analysis of land use transfer in the middle and upper reaches of The Fujiang River,the most obvious type of land transfer is from cultivated land to construction land,followed by forest land to cultivated land.Among the counties(districts and cities)under the jurisdiction of Youxian District,Fucheng District and Santai County,the largest transfer type is the conversion of cultivated land to construction land.In the process of land transfer in Jiangyou City and Pingwu County,the transfer type from forest land to cultivated land is the most frequent.In terms of the amount of land use transfer,the largest amount of land use transfer was forestland in the middle and upper reaches of Fujiang River,followed by Fucheng District,Youxian District and Santai County.In the process of land use transfer,the largest amount was cultivated land.However,jiangyou city and Pingwu County have the most frequent and extensive transfer of forestland.(3)Through the analysis of land use transfer and ecological sensitivity in the middle and upper reaches of The Fujiang River,it is found that the types of land use transfer gradually decrease with the increase of land ecological sensitivity.In non-sensitive and low-sensitive areas,the land use transfer mainly includes the transfer of cultivated land,grassland and forest land to construction land,water land and unused land.In moderately sensitive areas,the transfer of construction land,water land and unused land gradually decreases.In high and extreme erogenous zones,The land use type is mainly the mutual circulation between grassland and forestland.