基于灰色预测模型的长江经济带城市土地生态安全预警

Early-warning of URBAN LAND ECOLOGICAL SECURITY in Yangtze River Economic Belt based on Gray Forecasting Model

基于2005—2015年反映长江经济带各城市土地生态安全的相关数据,从压力、状态、响应三个层面构建土地生态安全评价指标体系,运用GM(1,1)模型对2016—2020年长江经济带各城市土地生态安全演变趋势进行预测,并结合预警指数和警度标准对2005—2020年长江经济带土地生态安全警情状况进行分析,旨在为长江经济带土地生态环境保护提供决策参考。研究结论如下:(1)2005—2015年长江经济带土地生态安全整体状况改善,土地生态安全级别由"较不安全"提高至"临界安全",但形势依然不容乐观;(2)2016—2020年长江经济带各城市土地生态安全警情出现向高、低警度两端聚集的趋势,"轻警"和"重警"城市增多,城市间土地生态安全水平差距将继续变大,且Ⅱ类大城市土地生态安全改善幅度最大;(3)长江经济带各城市土地生态安全状态呈现"东中部和西南部优,西北部劣"的格局,西北部的攀枝花市、凉山彝族自治州、甘孜藏族自治州、阿坝藏族羌族自治州等是土地生态安全敏感区;(4)经济密度、单位土地废水负荷和人均公园绿地面积是影响长江经济带土地生态安全的敏感因子,是今后调控的重点。

Based on the related data of land ecological security of the Yangtze River Economic Belt from 2005 to 2015,this paper constructed a land ecological security early-warning index system for the Economic Belt from three aspects which were pressure,state and response.And then it used the GM(1,1)model to make a prediction for the land ecological security development trend of the Economic Belt in 2016-2020,and at last made a warning analysis of the land ecological security of the Economic Belt from 2005 to 2020 according to the early-warning index and warning degree standards.There is certain reference value for protecting the land ecological environment.The conclusions are shown as follows.(1)The land ecological security state showed an upward trend in 2005-2015,and the degree of land ecological security was improved from"less safe"to"critical security",but the situation was still not optimistic.(2)The warning degree of land ecological security showed gathered on high or low,and the number of city would be increased in light alarm and heavy alarm,then the gap between cities would be increasing.The greatest improvement city was big city of classⅡ.(3)The ecological security status of urban land in the Economic Belt had shown a pattern of“excellent in the east and southwest”and“bad in the northwest”.The northwest cities had become sensitive area of land ecological security,such as Panzhihua City,Liangshan Yi Autonomous Prefecture,Ganzi Tibetan Autonomous Prefecture,Aba Tibetan and Qiang Autonomous Prefecture.(4)Economic density,unit land sewage load and per capita park green area were sensitive factors affecting the land ecological security in the Economic Belt.These are the focus of land ecological security regulation in the future.