Study On Identification Of Negative Factors Of Land Ecological Security

Studying the negative factors of land ecological security in Guangxi will help to improve the level of land ecological security and promote the construction of ecological civilization in Guangxi.In this study,using socio-economic data and land use data,the evaluation index system of land ecological security in Guangxi was constructed from four dimensions of quantity security,quality security,structural security and security.The comprehensive evaluation method and spatial autocorrelation model were used to evaluate the land ecological security of Guangxi in 2005,2010,2015 and 2018,and analyzes the spatial distribution characteristics of the county.Then,the impact factors of land ecological security are selected from the natural,economic and social aspects,and the Pearson correlation analysis method is used to screen the impact factors.The OLS model,GWR model and MGWR model are used to analyze the impact type and degree of the impact factors on the level of land ecological security in Guangxi,identify the negative impact factors of land ecological security in Guangxi,and analyze the impact mechanism of negative impact factors,so as to study the impact differences of different negative impact factors on different districts and counties in Guangxi,Finally,according to the difference of the negative impact factors of land ecological security on different districts and counties in Guangxi,some suggestions are put forward to improve the level of land ecological security in Guangxi.The results show that:(1)From 2005 to 2018,the level of land ecological security in Guangxi showed the characteristics of first decreasing,then increasing,and then decreasing,but the overall trend was increasing.The spatial difference of land ecological security level was large.The high-level agglomeration areas of land ecological security were mainly distributed in Hepu County and Yinhai District of Beihai City,Liunan District,Liubei District and Chengzhong District of Liuzhou City,Diecai District and Seven Star District of Guilin City.(2)The negative impact factors identified by OLS model,GWR model and MGWR model are mostly the same.The common negative impact factors identified are average slope,soil erosion rate,rocky desertification rate,cultivated land fragmentation,fertilizer application per unit cultivated land and industrial sulfur dioxide emission,It is found that the performance and fitting degree of MGWR model are better than the other two models,so MGWR model is more suitable for the identification of negative impact factors of land ecological security.(3)The impact of negative factors on land ecological security is quite different in Guangxi.The impact of negative factors on land ecological security is different in different districts and counties.(4)According to the impact mechanism of negative impact factors on land ecological security in Guangxi,the paper puts forward some countermeasures and suggestions,mainly including increasing the control of soil erosion,increasing the prevention and control of rocky desertification,reducing the amount of fertilizer per unit of cultivated land,promoting green economic development,adjusting and optimizing industrial structure,and promoting farmland consolidation project.