长江流域河长制治污效果及异质性分析

Analysis of the Effect and Heterogeneity of River Chief System on Pollution Control in the Yangtze River Basin

河长制的执行效果需要严谨的实证评估,而长江作为中华民族的母亲河,其水质的重要性不言而喻。利用有序probit模型,通过2014—2019年长江流域重点水域断面的月度水质数据,评估了河长制的政策效果。研究发现,相对于没有实施河长制改革的流域,河长制的执行显著提高了长江流域水体的质量。河长制的实施减少了当地污染排放行为的发生,同时通过污水治理改善了流域水质。通过选择性偏误及安慰剂检验,调整样本、改变窗口期等稳健型检验,进一步验证了基本结论的稳健性。最后,通过对长江流域监测断面是否处于国控点的检验分析发现,相对于其他水域,国控点水域在河长制实施后其水质显著提高,这意味着河长制的执行在地方执行时具有异质性。

The implementation effect of the river chief system needs rigorous empirical evaluation.As the mother river of the Chinese nation,the importance of the water quality of the Yangtze River is self-evident.Based on the monthly water quality data of key sections of the Yangtze River Basin from 2014 to 2019,this paper evaluates the policy effect of the river chief system by using the ordered Probit model.It is found that the implementation of the river chief system has significantly improved the water quality in the Yangtze River Basin compared with the basins without the reform.The implementation of the river chief system has reduced the occurrence of local pollution discharge and improved the water quality of the river basin through sewage treatment.This paper further verifies the robustness of the basic conclusions by using robust tests such as selective bias and placebo test,adjusting the sample and changing the window period.Finally,through the analysis of whether the monitoring section in the Yangtze River Basin is in the state controlled point,the paper finds that the water quality in the state controlled point waters is significantly improved compared with other waters after the implementation of the river chief system,which means that the implementation of the river chief system is heterogeneous at the local level.