Research On The Impact Path Of Urbanization On Haze Pollution Based On HLM Model

The level of urbanization development is an effective indicator of the progress of a country or region.Although the urbanization rate of Chinese population has reached60% in 2019,there is a big gap between the 80% average level of developed countries and,even in countries with similar levels of urbanization to China,Chinese per capita economic level is still far behind.Therefore,in the future,Chinese urbanization and social economy still have a large room for development.Urbanization is still the main theme of China current social and economic development,and it is an important carrier for entering a new era to build a modernist country.However,the process of urbanization inevitably brings a series of environmental pollution problems,among which the problem of haze pollution is particularly serious.This paper takes Chinese 279 prefecture-level cities from 2006 to 2019 as the research object,constructs a city-provincial multi-scale linear model,and uses the mediating effect test method of the hierarchical nesting theory to analyze the mechanism of urbanization development on haze pollution,the impact path,and the regional heterogeneity of the impact path from the national and sub-regional levels respectively,so as to provide a theoretical reference for the selection of haze pollution control paths.Firstly,an urbanization indicator system was constructed from the four dimensions of population urbanization,economic urbanization,land urbanization,and social urbanization.Taking into account that there may be multiple collinearity among different indicators,the entropy method is used to measure the urbanization of different dimensions.The urbanization level was measured and analyzed,and the results showed that:(1)There are differences in the urbanization of various dimensions in different periods,and there are also obvious differences between the development levels of different dimensions in the same period.(2)The level of urbanization in different dimensions and the haze pollution is not a simple linear relationship,but a hierarchical nesting relationship.Secondly,the HLM model is used to analyze the multi-scale effects of urbanization development on haze pollution.The results show that:(1)From the overall level of China,the multi-scale effect of urbanization on haze pollution has been tested,and the provincial level has reached 61.12% of the impact of haze pollution,which indicates that the haze pollution is caused by the city and the province.Determined by the two levels of the world,haze pollution has hierarchical nesting,and according to the results of multi-scale effect testing,it can be concluded that as the process of urbanization accelerates and develops,it can gradually aggravate the overall pollution impact of haze pollution in China,especially the development of population urbanization and land urbanization can aggravate the pollution level of Chinese haze pollution,and the development of economic urbanization and social urbanization can curb haze pollution to a certain extent.(2)When studying the multi-scale effects of urbanization on haze pollution at the sub-regional level in China,we found that for the eastern,central and western regions,the degree of pollution that affects haze pollution also comes from the municipal and provincial levels.The results of the scale effect test show that the degree and relationship of the impact of haze pollution in the east,middle and west regions of China are generally different and cannot be confused,there is obvious regional heterogeneity.Finally,using the mediating effect test method based on the hierarchical nesting theory,a two-layer HLM model was constructed from the perspective of city-provincial multi-scale correlation to analyze the impact path of urbanization on haze pollution.The results show that:(1)At the overall level of China,Urban＿people→ Mediating variable → haze pollution,Urban＿economic → Mediating variable → haze pollution,Urban＿land → Mediating variable → haze pollution and Urban＿society → Mediating variable → haze pollution have significant impact path.(2)At the sub-regional level,the impact path of Urban＿people → Mediating variable → haze pollution in the three regions of east,middle and west of China is also markedly established,and there is obvious regional heterogeneity in the impact path in different regions.The paper has 15 pictures,17 tables,and 84 references.