Study On Ecological Security Evaluation And Obstacle Factors Of Cultivated L And In Enshi Prefecture

As an important material guarantee for agricultural production and the survival and development of human society,cultivated land resources are the material basis for ensuring agricultural production and implementing the national strategy of "storing grain in the land and storing grain in technology".The safety evaluation of cultivated land ecosystem is an important part of the field of ecological security research.It plays an important role in the in-depth study and solution of the safety problems of cultivated land ecosystem and in promoting the construction of ecological civilization of human society.The pressure of population per unit cultivated land area in China is great,under the background of continuous economic and social development,the expansion of urban scale and the gradual promotion of industrialization,the frequent occurrence of cultivated land occupation,destruction and unreasonable use,the sharp decrease of cultivated land quantity,the soil pollution of cultivated land and the deterioration of the structure and function of cultivated land ecosystem,and a series of problems seriously threaten the ecological security and sustainable development of cultivated land resources.Enshi Prefecture,Hubei Province,was selected as the research area,and the factors affecting the ecological security of cultivated land were comprehensively considered,combined with the social,economic and ecological environment characteristics of Enshi Prefecture,using the "driving force pressure state impact response(DPSIR)" evaluation index model,18 representative index factors were selected to construct the evaluation index system of cultivated land ecological security in Enshi Prefecture,and the index factor weight was given by entropy weight method and the comprehensive index method was used to evaluate and analyze the ecological security level of cultivated land in Enshi Prefecture.Based on the comprehensive evaluation results,this paper analyzes the time series changes of cultivated land ecological security in Enshi Prefecture from 2008 to 2017,and takes 2011,2014 and 2017 as research samples to analyze the spatial differences of cultivated land ecological security in Enshi Prefecture.At the same time,according to the evaluation model of obstacle degree,it diagnoses and identifies the obstacle factors affecting cultivated land ecological security in Enshi Prefecture,so as to protect it And improve the ecological security level of cultivated land in Enshi Prefecture as the goal,combined with the actual situation of Enshi Prefecture put forward targeted countermeasures and suggestions.Through the research,the specific conclusions are as follows:(1)The ecological security level of cultivated land in Enshi Prefecture has become a positive development trend as a whole.The ecological security level of cultivated land in Enshi Prefecture can be roughly divided into three stages from 2008 to 2017:rapid rise,fluctuating decline and fluctuating rise:in the first stage,the ecological security level of cultivated land in Enshi Prefecture increased rapidly from 2008 to 2009,and the ecological security level of cultivated land increased from the risk level to the comparative security level;the second stage is that from 2009 to 2012,the ecological security level of cultivated land in Enshi Prefecture is generally fluctuating and declining,and the ecological security level of cultivated land is relatively stable and remains at a relatively safe level:the third stage is that the ecological security level of cultivated land in Enshi Prefecture in 2012-2017 shows an overall upward trend of fluctuation,and the ecological security level of cultivated land rises from the comparative security level to the security level,during which the overall situation of the ecological security level of cultivated land in Enshi Prefecture develops well.(2)The ecological security level of cultivated land in Enshi Prefecture has a good development trend,but there are obvious differences between counties and cities,as follows:in 2011,the ecological security status of cultivated land in counties and cities of Enshi Prefecture is not optimistic,and the spatial difference is large.Among them,the ecological security level of cultivated land in Hefeng County,Xianfeng County and Xuanen county is critical,that of Jianshi County,Badong County,Laifeng County and Lichuan City is sensitive,that of Enshi City is the lowest,and that of risk;compared with 2011,the comprehensive index of cultivated land ecological security in some counties and cities of Enshi Prefecture has been improved,and the status of cultivated land ecosystem has been greatly improved.As a whole,the level of cultivated land ecological security in Enshi Prefecture is developing well.Among them,the safety level of Hefeng County is relatively safe,that of Xianfeng County,Xuanen County,Jianshi County and Lichuan City is critical,and that of Laifeng County,Badong County and Enshi City is sensitive.It can be seen that the critical safety level of Hefeng County increased from 2011 to comparative safety level,and the sensitive level of Jianshi County and Lichuan City increased from 2011 to critical safety level;compared with 2014,the comprehensive index of cultivated land ecological security in Enshi Prefecture has been greatly improved in 2017,and the ecological security level of cultivated land in most counties and cities has changed greatly,among which,the ecological security level of cultivated land in Hefeng County,Xianfeng County and Xuanen county is relatively safe.The ecological security level of cultivated land in Jianshi County,Lichuan City,Enshi City,Badong County and Laifeng County is critical.It can be seen that Xianfeng County and Xuanen county increased from critical safety level to comparative safety level in 2014;and Enshi City,Badong County and Laifeng County increased from sensitive level to critical safety level in 2014.(3)The results of identifying the factors that affect the ecological security of cultivated land in Enshi Prefecture by the model of obstacle evaluation are as follows:① on the whole,in the ten years from 2008 to 2017,the obstacles of the driving factor criterion layer showed an upward trend,the obstacles of the pressure factor criterion layer showed a trend of first rising,then falling and then rising,and the changes of the obstacles of the state factor criterion layer were relatively stable,within a certain range There is a fluctuation in the index level of influencing factors,the barrier level of influencing factors shows a significant downward trend,while the barrier level of responding factors shows a downward trend first and then upward trend.② The main factors that affect the cultivated land ecosystem in Enshi Prefecture include population density,per capita net income of farmers,the proportion of primary industry in GDP,forest coverage and yield of drought and flood protection;the main factors that affect the cultivated land ecosystem are effective irrigation area ratio,rural electricity consumption,per capita GDP and regional GDP growth rate.(4)In order to protect and improve the security level of cultivated land ecosystem and promote the construction of ecological civilization in Enshi Prefecture,Enshi Prefecture should vigorously implement the following measures in the future:making and improving policies and regulations,changing the way of cultivated land utilization,strengthening the construction of agricultural infrastructure,actively preventing and controlling the ecological problems of cultivated land and establishing the monitoring and early warning mechanism of cultivated land ecosystem,so as to ensure the overall security of cultivated land ecosystem in Enshi Prefecture And improve the ability to resist risks.