环境规制对碳排放的门槛效应及其区域差异

为了深入探究我国环境规制的政策效应及其区域差异，采用我国30个省区2004—2014年的面板数据（不含港澳台及西藏自治区数据，下同），分别以能源强度、产业结构和FDI（外商直接投资）作为门槛变量，以环境规制为核心解释变量，利用面板门槛模型分析我国环境规制对碳排放的门槛效应及其在东部、中部和西部存在的区域差异.结果表明:由于能源强度、产业结构、FDI这3个门槛变量的作用，环境规制对碳排放的影响体现出非线性特征，且环境规制的政策效应在东部、中部和西部3个区域内存在较为明显的差异.东部地区的环境规制在3个门槛变量的中低门槛区间均不能促进碳减排，处于高门槛区间时，能源强度会促进碳排放，而产业结构和FDI这两个门槛变量则对碳排放有抑制作用，其中能源强度跨过第2个门槛值（1.111 8）后仍表现出对碳排放的促进作用，产业结构（0.566 1）和FDI（1 159.40×108元）分别跨过第2个门槛值后，对碳排放表现出抑制作用；中部地区在能源强度的影响下，环境规制对碳排放一直为抑制作用，在产业结构和FDI的影响下则一直是促进作用；西部地区的能源强度与碳排放呈倒“U”型关系，两个门槛值分别为1.200 8与2.153 3，以产业结构和FDI为门槛变量时，环境规制均未能发挥碳减排作用，一直体现为促进作用.因此，政府在实施环境规制政策时不能采取一刀切的措施，要根据东部、中部和西部的不同情况针对性地实施相应的环境规制政策. 

Threshold Effect and Regional Differences of Environmental Regulation on Carbon Emission

Using the panel data of 30 provinces in China from 2004 to 2014(the data do not include Hong Kong, Macao, Taiwan and Tibet Autonomous Region), taking energy intensity, industrial structure and foreign direct investment (FDI) as threshold variables respectively, taking environmental regulation as core explanatory variable, this paper analyzed the threshold effect and regional differences of environmental regulation in China on carbon emission by the panel threshold model. The results show that because of the threshold effect of three variables, the influence of environmental regulation on carbon emissions reflect the nonlinear characteristics, and the effects of the policy of environmental regulation in the eastern, central and western areas are different obviously. The environmental regulation in the eastern region cannot promote the carbon emission reduction in the low threshold range of the three threshold variables, and the energy intensity within the high threshold interval would promote the carbon emission, however, the two threshold variables of industrial structure and FDI have inhibitory effect on carbon emission. The energy intensity over the second threshold value of 1.1118 still shows the promoting effect of carbon emissions, industrial structure and FDI across a second threshold value of 0.5661 and 115.94 billion RMB respectively, showed inhibitory effect on carbon emissions. Under the influence of energy intensity in the central region, environmental regulation has a restraining effect on carbon emission, while has a positive effect by the influence of industrial structure and FDI. The energy intensity and carbon emission in the western region are inverted u-shaped and the thresholds are 1.2008 and 2.1533 respectively. The environmental regulation fails to play the carbon emission reduction role, when the industrial structure and FDI are the threshold variables. Therefore, the corresponding environmental regulation policies should be implemented in accordance with the different situations in the eastern, central and western regions. The research content of this article is limited, and there are many space for us to expand in many ways, such as what impact will the goal of carbon emission reduction have on China''s economic development and how to design in different parts of the carbon reduction policy, etc.