Evaluation And Influencing Factors Of Land Ecological Security In Ecologically Fragile Area Of Northwest Shanxi Province

Land is an important carrier of economic and social development.With the development of economy and society,the economic density of land has been greatly increased,and the GDP has been promoted year after year.The over-intensity development has weakened the carrying capacity of land resources,and land ecological security is the basis to ensure the continuous improvement of regional ecological environment,and an important content to continue to promote the all-round,regional and whole-process ecological civilization construction.The northwest of Shanxi Province is located in the northwest edge of Shanxi Plateau,which is an important part of the northern farming-animal husbandry ecstatic zone and an important ecological barrier to windbreak and sand consolidation in Beijing and Tianjin.However,due to the influence of natural climate factors and human activities,the phenomenon of soil desertification and soil erosion is serious.In this regard,governments at all levels have implemented a number of ecological control projects and achieved remarkable results.However,the ecological problems have not been fundamentally solved yet.In this paper,9 counties and districts in northwest Shanxi were selected as the research area.Based on PSR model,the evaluation index system was constructed from six aspects: land bearing pressure,socio-economic pressure,land use structure,socio-economic status,ecological response and socio-economic response,which accurately represented the land ecological status in northwest Shanxi.Taking 2010,2015 and 2020 as the study period,the entropy method was used to assign weight,and the land ecological security of each county was deeply analyzed from the spatio-temporal scale.The obstacle factor model was used to explore the main factors affecting the land ecological security in the ecologically fragile area of northwest Shanxi Province,and the corresponding suggestions were put forward in order to provide scientific basis for the land management and the sustainability of ecological security in the sandstorm area of northwest Shanxi Province.The results are as follows:(1)The land ecological security level of counties and districts in northwest Shanxi is gradually improving,and the comprehensive index of land ecological security changes from 0.22-0.45(2010)to 0.29-0.56(2015),and then rises to 0.35-0.58(2020).At present,the comprehensive index of land ecological security in Pianguan County and Baode County is low,fluctuating around 0.36,and still in the "relatively unsafe" level.(2)The spatial distribution of land ecological security in northwest Shanxi is characterized by "low outside and high inside",and the difference between inside and outside is obvious.At the end of the study period,the comprehensive index of land ecological security in Baode County,Hequ County,Pianguan County,Pinglu District,Youyu County and Zuoyun County in the northwestern edge of Shanxi was 0.35-0.46,which was in the grade of "critical security" or below.The land ecological security in Wuzhai County,Shenchi County and Shuocheng District is relatively good,and the comprehensive index in 2020 is 0.51-0.58,which is in the "relatively safe" level.(3)The main factors affecting the land ecological security of northwest Shanxi counties were the per capita disposable income of rural residents(14.15%),per capita grain output(12.35%),per capita GDP(11.77%),land economic density(11.10%),agricultural output value(7.34%).The results indicated that the regional economic development still exerted great pressure on the land ecosystem,and the forest and grass land area(8.81%)was related to the rationality of land structure,and also directly affected the land ecological security in the study area.The results show that the land ecological security level in northwest Shanxi is low under the comprehensive action of human disturbance and ecological space atrophy.In order to improve the land ecological security,some suggestions are put forward:developing characteristic industries and optimizing industrial structure;Control the expansion of construction land to ensure the ecological space;Strengthen the quantity protection of cultivated land,improve the quality of cultivated land;We will comprehensively promote high-quality and high-yield organic dry farming.To improve the ecological condition of land in northwest Shanxi to the greatest extent and ensure the sustainable development of land resources.