博尔塔拉蒙古自治州近20年土地生态安全评价与趋势分析

土地生态系统是陆地生态系统的重要组成部分,但在快速城市化的背景下,区域、国家和全球尺度上的土地生态系统发生退化现象,因此为保障土地生态系统的可持续发展,有必要对当前土地生态安全进行评价。选用压力-状态-响应-自然-社会-经济(PSR-NSE)评价指标体系,利用熵权法对指标重要性进行排序,建立了博州土地生态安全突变评价模型。结果表明:1)博州的土地生态安全等级自1994年的0.83(Ⅴ)持续改善至2012年的0.98(Ⅱ);2)博州是西北干旱生态脆弱区,仅通过人为调节并不能保证区域土地生态安全,应着手区域的均衡发展和区域生态保障措施的实施;3)基于突变级数法构建突变模型,分析了系统潜在的突变特性和土地生态安全的发展趋势,表明博州近20年土地生态安全水平虽呈逐年上升趋势,但整体水平不高,土地生态系统整体状态仍待改善。

Evaluation and trend analysis for the land ecological security of the Bortala Mongolia Autonomous Prefecture,Xinjiang, for the recent 20 years

This paper is inclined to present its study on the land ecological security of the region of the Bortala Mongolia Autonomous Prefecture (ab.Bortala prefecture),Xinjiang.For the said research purpose,we would like to take Bortala prefecture as our case study sample.With the fast step going on with the regional urbanization,our study becomes urgent on the analysis of the potential catastrophic characteristics of the arid regions.And,with the application of PSR-NSE (pressure-state-response and nature-social-economy) framework and catastrophe progression method,this paper has developed a catastrophe model for the assessment of land eco-security,and assessed the ecological security status of the prefecture from 1994 to 2013.In accordance with the catastrophe model,we have first of all constructed the index system with the twenty-three indexes reflecting the regional pressure,state,response,and use entropy weight method to determine the index weights.The obtained data were from the Bortala prefecture statistic yearbook.The results of our investigation and analysis indicate that,although Bortala prefecture land ecological security continues to improve from 0.83 (Ⅴ) of 1994 to 0.98 (Ⅱ) of 2012,all the year round Bortala prefecture was in marginally secure/insecure state.At the same time,the three subsystems are presenting security trends.Bortala prefecture is drought and ecology vulnerable in the Northwest region,only through artificial factors for regulation cannot guarantee regional land ecological security long-term in security state,we should start balanced development and ecological guarantees measures on Bortala prefecture.Using the catastrophe progression method building catastrophe model of land ecological security,our research results help to reveal the catastrophic effects of large development projects on ecosystems when a single index was at extreme.Therefore,the evaluation results and the main environment problems we have found in the region for the time being may all help to find the main inadequacies in the region's land ecological security construction.Thus,our work can be taken as a reference to the promotion of establishing a scientific strategy for further development of the region's land ecological security.