长江经济带城市污染排放分布动态及趋势

Distributional dynamic and trend prediction of urban pollution emission in Yangtze River Economic Belt

基于长江经济带108个城市的数据,利用熵值法构建了污染排放的综合指标,采用核密度估计法分析了城市污染排放的分布动态,并通过传统及空间马尔科夫链方法考察了城市污染排放的长期转移趋势和空间依赖性。结果显示:长江经济带中游、下游与总体污染排放强度均有所提升,且城市间差距均有所拉大,多极化趋势不明显;高污染和低污染水平城市污染排放的内部流动性较低,存在俱乐部趋同特征,且就转移概率而言,向相邻类型转移的概率较大,跳跃式转移的概率较小;城市污染排放的空间依赖性较强,若"邻居"为高污染水平,则本地区污染水平"向上转移"的可能性就较大,若"邻居"为低污染水平,本地区污染水平就有更多的"向下转移"的可能性。

Based on 108 urban data of The Yangtze River Economic Belt,and using the Entropy Method to construct comprehensive indicator of urban pollution emission,this essay analyzes the distributional dynamics of urban pollution emission in Yangtze River Economic Belt by Kernel Density Estimation and observes the long - term transfer trend and spatial dependence of urban pollution emission in Yangtze River Economic Belt by the methods of Markov Chain.The results show that :Firstly, the features of distributional dynamics in middle reaches and lower reaches of Yangtze River are basically consistent with collectivity,the intensity of pollution emission gone up;Secondly, the gap of intensity of urban pollution emission becomes greater and there is no multipolarization trend of urban pollution emission.As for the internal mobility of urban pollution emission, high and low level cities are lower and there is partly club convergence;Thirdly,as for the transition probability,the probability of transferring to neighboring types is greater and the probability of skip metastasis is less;Fourthly.the intensity of pollution emission has strong spatial dependence,that is,if adjacent areas have higher pollution emission levels,the region will have greater possibilities to move up,while if adjacent areas have lower pollution emission levels,the region will have greater possibilities to move down.