Research On The Character Of Spatial Correlation Of Haze Pollution And Its Cause In Large Scale Of China

At present,there exists some common misunderstanding about the regional characteristics of haze pollution over China,which leads to the misplaced foundation of collaborative governance mechanism for haze pollution,and eventually leads to the failure of the treatment for haze pollution.Based on the nonparametric approach to detect Granger causality,the paper identifies the spatial dependence relationship of haze pollution across279 cities in China.Diversified network analysis method and rolling window technology are used to reveal the global characteristic and microstructure of haze pollution spatial correlation.Finally,the paper utilizes exponential random graph model?ERGM?to investigate the determining factors in the formation of the spatial correlation.The conclusions are as follows:?1?There exists spatial dependence relation ship of haze pollution across sample cities,and the intensity of spatial correlation is gradually rising.Frequent burst of haze pollution in recent years of China may be due to the increasingly strengthened regional characteristics of haze pollution.?2?Regional haze pollution is not simply the sum of haze pollution in each city across the region,spatial correlation of haze pollution can not reduce to the attribute of each city.Correspondingly,the collaborative governance mechanism for haze pollution should reconstruct the mode of collaboration among participating cities from the overall perspective.?3?Estimated results of ERGM show that in addition to network self-organizing effects and nature factors,human-related factors also play important roles in the formation of spatial correlation of haze pollution.Based on the nonparametric econometric method and network analysis,the paper investigates the regional characteristic from the aspect of global characteristic,microstructure,influencing factors,and refutes the misperceptions about haze pollution and its regional transport.The conclusions of the paper can help to establish people's subjective initiative in haze controlling.Long-lasting expansion of haze pollution has already presented a stern challenge to regional joint prevention and control.In order to effectively deal with severe pollution weather,there is an urgent need to enlarge and reconstruct the coverage of joint prevention and control of air pollution in key area.Air quality models can identify and quantify the regional contribution of haze pollution and its key components,but it is difficult to be applied to larger spatial scale due to the complexity of model parameters and the constraint of sampling cost.The time series analysis can recognize the existence of spatial interaction of haze pollution between cities,but it has not yet been used to further identify the spatial influence of haze pollution and its contribution in large scale.Using econometric framework of time series analysis,this paper calculates the contribution from spatial interaction for each sample city in China,with the help of the monitoring data of PM_2.5.The results are as follows:?1?The change in the haze level of the sample cities is affected by other regions.?2?The interaction between haze pollution in different cities has dynamic structural changes.The contribution of external sources is increasing from the general trend.To enlarge and reconstruct the coverage of joint prevention and control in current China should take source apportionment into full consideration and follow the principle of"geographical distance---administrative subordination---spatial interaction".