| Under the dual pressure of economic growth and energy conservation and emission reduction,how to balance economic development and carbon emissions has become an important issue affecting China’s sustainable development.With the acceleration of urbanization,urban areas become the main body of carbon emissions.The continuous improvement of urbanization level has expanded people’s demand for energy consumption in production,life and other aspects,thus further increasing carbon dioxide emissions.Therefore,urbanization must be considered in the research of carbon emission reduction in China.In this paper,panel data of 30 Chinese provinces(except Xizang province)from 2000 to 2018 were selected,and the carbon dioxide emissions of China’s provincial regions were calculated by energy consumption,energy standard coal coefficient and carbon dioxide emission coefficient published by IPCC.Then,based on STIRPAT’s model,a panel regression model of the factors affecting China’s carbon emissions is constructed by taking the size of urban population,per capita GDP,energy structure,energy intensity,industrial structure and urbanization rate as environmental factors to calculate the impact of each factor on carbon emissions.According to the urbanization level,the provinces and cities in China are divided into three categories,from high to low.Finally,taking the urbanization rate as the threshold variable,the threshold effect of China’s carbon emission reduction was studied,and threshold regression was carried out for three regions from the perspective of urbanization.The results show that the urban population size,urban per capita GDP,energy structure,industrial structure and urbanization rate play a significant role in promoting China’s carbon emissions,while energy intensity has a significant inhibitory effect on China’s carbon emissions.Among these factors,the industrial structure is the leading factor affecting China’s carbon emissions.From the perspective of urbanization,different factors have different impacts on carbon emissions in different regions,and their robustness also shows some differences.In regions with the highest level of urbanization,population size is the dominant factor affecting carbon emissions.The energy structure is the leading factor affecting carbon emissions in the middle and lowest level of urbanization.Then,the urbanization rate is used as the threshold variable to study the threshold effect of China’s carbon emissions,and a double threshold can be obtained,with the threshold values of 0.4762 and 0.6931.When the second threshold is crossed,the impact of urbanization rate on carbon emissions increases.Then,from the perspective of urbanization,the leading factors affecting the carbon emissions of the three regions were taken as threshold variables to conduct a sub-regional regression.According to the analysis,in the regions with the highest level of urbanization,population size has no threshold effect on carbon emissions.In regions with medium and lowest urbanization levels,the energy structure has a single threshold effect,with thresholds of 0.6278 and0.6783,respectively.Among them,regions with medium level of urbanization are still within the threshold,while regions with the lowest level of urbanization have crossed the threshold,strengthening their role in promoting carbon emissions. |
