Abstract: With the rapid economic development of our country, the problem of industrial pollution is increasingly serious. After entering the 21st century, the limitations of the traditional pollution control model continue to appear, and the third-party governance model based on the “the polluter pays” principle has opened a new idea of environmental governance, and has been quickly paid attention to by government departments. In order to further improve the emission reduction level of enterprises, the Environmental Protection Tax Law was officially implemented in 2018, and its preferential policies are designed to encourage polluters to exceed the standard of pollution discharge, but the reality shows that the incentive effect of environmental protection tax preferential policies on enterprises still needs to be improved. Therefore, some scholars put forward the suggestion of adjusting the tax rate and designing multiple relief gradients to achieve the layer-by-layer induction of polluters. It is of great significance to study how the preferential mechanism of environmental protection tax affects the decisions and profits of polluters and environmental service providers, and how to improve the incentive level of the preferential policy of environmental protection tax.
Based on the third-party governance model of environmental pollution, considering the secondary environmental service supply chain composed of polluter and environmental service provider, the supply chain models under the two preferential mechanisms of tax reduction in grades and linear tax reduction are respectively constructed. Using Stackelberg game theory, the impact of the environmental protection tax reduction policy and the increase in preferential grades on the production and emission reduction decisions of enterprises is quantitatively studied. The results show that: under the graded preferential policy, with an increase in emission reduction ratio, the output and profit of the polluter increase, and the profit of the environmental service provider increases. However, there is a “difficult area for emission reduction” when the preferential interval is crossed, and the environmental service provider lacks the motivation for upgrading technology, which inhibits the incentive effect of environmental tax incentive policy to a certain extent. Compared with the graded preferential policy, the “difficult area for emission reduction” under the linear preferential policy disappears. When the emission reduction ratio is the same, the output and profit of the polluter increase, the social welfare effect is better, the profit of the environmental service provider is damaged, and the emission reduction cost level of the environmental service provider increases. Raising tax rates can ease the impact on environmental service providers.
Different from previous articles on preferential policies of environmental protection tax, based on the realistic policy background, this paper quantitatively analyzes the impact of two environmental tax reduction mechanisms on polluters, environmental service providers and social welfare through the establishment of mathematical models, and obtains some management implications. This will help the government continue to improve the tax system and collection and administration, guide enterprises to improve the level of emission reduction, and create a healthier third-party governance market environment.

Key words: third-party governance of environmental pollution, environmental tax preferential policy, Stackelberg game, social welfare

摘要： 基于环境污染第三方治理模式,考虑由排污企业和环境服务商构成的二级环境服务供应链,分别构建分档减税和线性减税两种优惠机制下的供应链模型,运用Stackelberg博弈理论,定量分析环保税分档减税政策以及增加优惠档次对企业生产及减排决策的影响。研究结果表明:分档优惠政策下,随着减排比例增加,排污企业的产量和利润增加,环境服务商利润整体趋势增加,但在跨优惠区间时存在“减排困难区”,缺乏技术升级动力,一定程度上抑制环保税优惠政策的激励效果;相对于分档优惠政策,线型优惠政策下“减排困难区”消失,实现同等减排比例时,排污企业产量及利润增加,社会福利效果更优,但环境服务商利润受损,且对其减排成本水平要求提高,提高税率可缓解对环境服务商的冲击。

关键词: 环境污染第三方治理, 环保税优惠, Stackelberg博弈, 社会福利