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国家COVID-19控制措施对中国水质的影响,使用改进的双重差异差异方法

Jian Zhao¹, Qingqing Liu¹, Jing Bai¹

¹State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, No.8 Anwain Dayangfang Road, Beijing 100012, China.

The Science of the total environment

|August 5, 2023

概括

通过减少总 (TN) 和化学氧气需求 (COD_Mn),COVID-19封锁改善了水质. 然而,非封锁措施的效果不一,凸显了需要多样化污染控制策略的需要.

科学领域:

环境科学环境科学
水质管理水质管理
环境政策环境政策

背景情况:

随着COVID-19的流行,全球环境发生了变化,水生生态系统成为一个关键的关注领域.
关于COVID-19对中国水生环境的影响的国家级研究仍然有限.
了解不同控制措施对水质的影响对于有效的环境政策至关重要.

研究的目的:

分析COVID-19及其相关控制措施对中国各地水质的影响.
为了比较正式封锁政策与非正式控制措施对水生污染物的影响.
研究这些影响的时空变化和异质性.

主要方法:

使用了一种改进的双空间时间差异差异 (DDiD) 方法.
分析了有或没有正式封锁政策的城市的水质数据.
采用异质性分析来识别污染源的变化.

主要成果:

正式封锁显著降低了总 (TN) 和化学氧需求 (COD_Mn) 度.
非正式的测量结果显示了不同的效果,增加TN,同时降低COD_Mn.
时空分析显示TN立即减少,但对COD_Mn有滞后的影响.
污染源的异质性影响了控制措施的有效性,工业城市显示出更大的TN减少.

结论:

由于各种污染源,COVID-19对水质的整体影响不如大气环境的影响显著.
中国表现出有效的点源控制,但进一步的减少,特别是来自工业来源的减少是有限的.
改善水生环境需要提高生态系统能力,减少来自所有污染源的排放,特别是非点源的排放.

关键词:

COVID-19 的影响影响.差异中的差异模型的差异.锁定封锁锁定封闭河流结构河流结构水的质量水的质量

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