基于乡镇尺度的耕地生态安全时空格局演变——以鹰潭市为例

Spatial-temporal pattern of cultivated land ecological security at a township scale in Yingtan city

耕地生态安全是保证耕地健康可持续利用的基础。本研究从乡镇尺度构建基于PSR模型的耕地生态安全评价指标体系,综合运用灰色关联模型和熵权组合法,动态评估鹰潭市1995-2015年耕地生态安全状况,并结合Markov链模型和热点分析对其时空格局演变进行分析。结果表明:(1)鹰潭市大部分乡镇耕地生态安全压力和状态呈恶化趋势,在响应措施的综合作用下,鹰潭市整体耕地生态安全呈现上升趋势。(2)临界安全级和比较安全级乡镇数量增多,“两极分化”日趋显著,临界安全级乡镇主要位于行政中心所在地及周边重要乡镇。(3)空间格局上,冷点聚类区向中西部扩大,热点聚类区集中于南北部且范围不断向中心城镇延伸。研究结果为提升耕地生态安全水平和协调区域耕地可持续利用提供借鉴。

The ecological security of cultivated land is the basis for ensuring the healthy and sustainable use of cultivated land.In this study,the evaluation index system of cultivated land ecological security was constructed on the township scale based on PSR model.The comprehensive assessment of cultivated land ecological security in Yingtan city from 1995 to 2015 was conducted by using the grey system theory and entropy weight-hierarchical analysis group method.The Markov chain model and hotspot analysis method was used to analyze the spatio-temporal pattern.The results showed that the cultivated land ecological security pressure and state of most towns and villages in Yingtan city were deteriorating,and the overall ecological security of the cultivated land in Yingtan city showed a rising trend under the comprehensive action of the response measures.The number of critical safety level and safer level towns was increasing,and the"polarization"phenomenon was becoming increasingly significant.The critical safety level towns were mainly located in the important towns of the administrative center and surrounding areas.In the spatial pattern,the cold point clustering zone was expanding to the central and western regions.However,the hotspot clustering area was concentrated in the north and south area and extended to the central town.These results can provide reference for the improvement of ecological security level and sustainable utilization of cultivated land.