耕地生态安全动态评价及障碍因子诊断——以黄河下游沿黄县区为例

Dynamic Evaluation and Obstacle Factor Diagnosis of Cultivated Land Ecological Security--A Case Study at Counties Along Lower Yellow River

[目的]对黄河流域下游耕地生态安全进行动态评价,并诊断其人为障碍因子,旨在发现人类不合理行为对下游耕地生态安全造成的危害,为黄河下游生态保护和高质量发展提供现实科学依据。[方法]以黄河下游沿黄49县区为研究对象,基于PSR模型构建耕地生态安全评价指标体系,运用物元可拓、马尔科夫链模型等方法开展研究。[结果]①2000—2018年黄河下游沿黄县区耕地生态安全等级整体呈上升趋势,由Ⅳ级提升到Ⅰ级,其中2010年后变化尤为明显;②2000—2018年各县区耕地生态安全等级由不稳定向稳定过渡,在空间上呈现由东北部高,中西部低向东北—西南部高,中部低转变的特征,且空间差异持续缩小;③人均耕地面积、人口密度、单位耕地面积化肥使用量是影响黄河下游沿黄县区耕地生态安全等级的主要人为障碍因子。[结论]研究期内黄河下游沿黄县区耕地生态安全等级总体呈上升趋势,各县区耕地生态安全等级空间差异持续缩小,受人类活动因素影响较大。未来应从壮大新型农业经营主体、实施归雁工程、构建智慧耕地平台三方面促进黄河流域耕地生态安全等级的提高。

[Objective]The ecological security of cultivated land in the lower reaches of the Yellow River was dynamically evaluated to diagnose the factors of man-made obstacles,in order to discover the harm caused by unreasonable human behaviors to the ecological security of cultivated land and provide realistic scientific basis for ecological protection and high-quality development of the lower reaches of the Yellow River.[Methods]The cultivated land ecological security evaluation index system was established based on PSR model in 49 counties along the lower reaches of the Yellow River,and matter-element extension and Markov chain model were used in the analysis.[Results]①From 2000 to 2018,the ecological security level of cultivated land in counties along the lower reaches of the Yellow River showed an overall upward trend,from levelⅣto levelⅠ,especially after 2010.②From 2000 to 2018,the cultivated land ecological security level of each county and district had a transition from unstable to stable,showing a spatial transition from higher in the northeast and lower in the central and western regions to higher in the northeast-southwest and lower in the central region,and the spatial differences continued to shrink.③Per capita arable land area,population density,and the amount of chemical fertilizer used per arable land area were the main human obstacles affecting the ecological security of cultivated land in the lower reaches of the Yellow River.[Conclusion]During the study period,the ecological security level of cultivated land along the lower reaches of the Yellow River showed an upward trend,and the spatial difference of cultivated land ecological security level in each county continued to narrow,which was greatly affected by human activities.In the future,we should promote the improvement of cultivated land ecological security level in the Yellow River basin from three aspects:expanding new agricultural management subjects,implementing geese returning project and constructing intelligent cultivated land platform.