Based On The CRITIC Weighted Gray Target Model Evaluation Of Ecological Security In Liquan County

Land ecological security means that the land ecosystem is in a balanced and healthy state in terms of internal structure,function and external performance,so as to maintain the sustainable development of nature,society and economy.In recent years,with the rapid development of social economy and the strong promotion of China’s urbanization and industrialization,the regional land ecological pressure is increasing,which seriously endangers the land ecological security.Therefore,it is necessary to carry out land ecological security evaluation.Based on the analysis of land use status in Liquan County,Shaanxi Province,this paper selects 18 indicators to build land ecological security evaluation index system with the help of "pressure state response" concept(PSR)model,uses critical weighting method to determine the index weight,and uses the improved grey target model to evaluate and analyze land ecological security status in Liquan county from 2010 to 2018 Finally,based on the ESDA model,the spatial differentiation characteristics of land ecological security in Liquan county are discussed.Finally,according to the research results,some suggestions are put forward,which are of great significance to improve the level of land ecological security in Liquan county.The results are as follows1.From the perspective of land use structure and landscape pattern,the spatial and temporal changes of land use pattern in Liquan county from 2010 to 2018 were analyzed.The land type of Liquan county is mainly agricultural land,and cultivated land,garden land and grassland occupy an absolute proportion.Garden land is the most important land type in Liquan County,with an area of about 52% of the total land area.With the opening and operation of Xiping railway,the growth rate of land for transportation in Liquan county is the largest in recent years,which belongs to the rapid growth type.From the analysis of landscape pattern,it can be seen that land use types change frequently in Liquan County,the degree of separation between land types is gradually increasing,land use types are staggered,the connection between types is less,and the distribution of land use types presents a trend of fragmentation.2.Based on relevant literature research,this paper selects 18 indicators from three aspects of land ecological security pressure,land ecological security status and land ecological security response to evaluate and analyze land ecological security of Liquan county from 2010 to 2018.The pressure of land ecological change mainly includes cultivated land per capita,population density,natural population growth rate and other indicators;the state of land ecological security mainly includes landscape fragmentation,green coverage and other indicators;the response of land ecological regulation mainly includes sewage treatment rate,the proportion of the tertiary industry and other indicators.3.Using critical weighting method to determine the variability and conflict of the indicators,through the calculation of the amount of information to determine the objective weight of 18 evaluation indicators.According to the objective weight,population density and construction land development intensity are the main factors affecting land ecological security in Liquan county.4.The improved grey target model is used to evaluate the land ecological security of Liquan county.The calculation shows that the ecological security target degree of Liquan county is 0.8059 in 2010,0.7331 in 2014 and 0.8137 in 2018.The results show that the land ecology of xizhangpu town and Qiandong town are in an unsafe state in the three research periods,and the development trend of land ecological security of other towns is good.5.The results show that the overall land ecological security is good,but the spatial distribution is not balanced.The areas with high land ecological security are concentrated in Chengguan Town,the central urban area of Liquan County,Chigan Town,an important town of ecological protection,and some areas of Fenghuo town and Jianling Town,which mainly focus on cultural relics protection.The areas with low degree of land ecological security are mainly concentrated in xizhangbao town and Qiandong town in the southeast of Liquan County,which are supported by industrial and mining industries.6.By analyzing the existing problems of land ecological security in Liquan County,combined with the actual situation of Liquan county and the future land use development arrangement,this paper puts forward corresponding suggestions and countermeasures,so as to promote the sustainable development of economy and society in Liquan county.