Institute of Central China Development, Wuhan University, Wuhan 430072, China.
Institute of Regional and Urban-Rural Development, Wuhan University, Wuhan 430072, China.
Int J Environ Res Public Health. 2021 Jan 6;18(2):382. doi: 10.3390/ijerph18020382.
Innovation agglomeration plays a decisive role in improving the input-output scale and marginal output efficiency of factors. This paper takes carbon emissions as the unexpected output and energy consumption as the input factor into the traditional output density model. The dynamic spatial panel Durbin model is used to analyze the mechanism for innovation agglomeration and energy intensity to affect carbon emissions from 2004 to 2017 in thirty Chinese provinces. Then, we test the possible mediating effect of energy intensity between innovation agglomeration and carbon emissions. The major findings are as follows. (1) The carbon emission intensity has time-dependence and positive spatial spillover effect. That is, there is a close correlation between current and early carbon emissions, and there is also a high-degree correlation between regional and surrounding areas' carbon emissions. (2) Carbon emissions keep a classical inverted U-shaped relation with innovation agglomeration, as well as with energy intensity. However, the impact of innovation agglomeration on carbon emissions in inland regions of China does not appear on the right side of the inverted U-shaped curve, while carbon emissions are subject to a positive nonlinear promoting effect from energy intensity. (3) When the logarithm of innovation agglomeration is more than 3.0309, it first shows the inhibition effect on energy intensity. With the logarithm of innovation agglomeration exceeding 5.0100, it will show the dual effect of emission reduction and energy conservation. (4) Energy intensity could work as the intermediary variable of innovation agglomeration's influence on carbon emissions. Through its various positive externalities, innovation agglomeration can produce a direct impact on carbon emissions, and through energy intensity, it can also affect carbon emissions indirectly.
创新集聚在提高要素投入产出规模和边际产出效率方面起着决定性作用。本文将碳排放作为意外产出，将能源消耗作为投入要素纳入传统的投入密度模型中。利用动态空间面板 Durbin 模型，分析了 2004 年至 2017 年间中国 30 个省份的创新集聚和能源强度对碳排放的影响机制。然后，我们检验了能源强度在创新集聚和碳排放之间可能的中介效应。主要发现如下：（1）碳排放强度具有时间依赖性和正的空间溢出效应。也就是说，当前和早期的碳排放之间存在密切的相关性，而且区域和周边地区的碳排放之间也存在高度的相关性。（2）碳排放与创新集聚以及能源强度之间存在经典的倒 U 型关系。然而，在中国内陆地区，创新集聚对碳排放的影响并没有出现在倒 U 型曲线的右侧，而能源强度对碳排放则呈现出正向的非线性促进效应。（3）当创新集聚的对数大于 3.0309 时，它首先对能源强度表现出抑制作用。当创新集聚的对数超过 5.0100 时，它将表现出减排和节能的双重效应。（4）能源强度可以作为创新集聚对碳排放影响的中介变量。通过其各种正外部性，创新集聚可以直接对碳排放产生影响，也可以通过能源强度间接影响碳排放。
