Kutralam-Muniasamy Gurusamy, Pérez-Guevara Fermín, Roy Priyadarsi D, Elizalde-Martínez Ignacio, Chari Shruti Venkata
Department of Biotechnology and Bioengineering, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Ciudad de Mexico, México.
Nanoscience and Nanotechnology Program, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Ciudad de Mexico, México.
Environ Earth Sci. 2022;81(11):316. doi: 10.1007/s12665-022-10430-9. Epub 2022 May 29.
The Santiago River (Jalisco) is a major waterway in western Mexico and has received considerable attention due to its severe pollution. Understanding the impact of reduced human activity on water quality in the Santiago River during the COVID-19 lockdown (April-May 2020) is critical for river management and restoration. However, there has been no published study in this context, presenting a significant knowledge gap. Hence, this study focuses on determining if the nationwide COVID-19 lockdown influenced or improved surface water quality in a 262-km stretch of the Santiago River upstream. Data for 15 water quality parameters collected during the lockdown were compared to levels obtained in 2019 (pre-lockdown), 2021 (unlock), and the previous eleven years (2009-2019). The values of turbidity, BOD, COD, TSS, f. coli, t. coli, nitrate, sulfate, and Pb decreased by 4-36%, while pH, EC, total nitrogen, and As increased by 0.3-21% during the lockdown compared to the pre-lockdown period, indicating a reduction in organic load in the river due to the temporary closure of industrial and commercial activities. An eleven-year comparison estimated a 0-38% decline in pH, TSS, COD, total nitrogen, sulfates, nitrates, and Pb. The unlock-period comparison showed a significant rise of 3-37% in all parameters except As, highlighting the potential repercussions of restoring activity along the Santiago River. Estimated water quality indices demonstrated short-term improvements in river water quality during the lockdown when compared to other time periods investigated. According to factor analysis, the main pollution sources influencing river water quality were untreated household sewage, industrial wastewater, and agricultural effluents. Overall, our analysis showed that the COVID-19-imposed lockdown improved the water quality of the Santiago River, laying the groundwork for local officials to identify pollution sources and better support environmental policies and water quality improvement plans.
The online version contains supplementary material available at 10.1007/s12665-022-10430-9.
圣地亚哥河（哈利斯科州）是墨西哥西部的一条主要水道，因其严重污染而备受关注。了解2020年4月至5月新冠疫情封锁期间人类活动减少对圣地亚哥河水质量的影响，对河流管理和恢复至关重要。然而，目前尚无这方面的已发表研究，存在重大知识空白。因此，本研究着重确定全国范围的新冠疫情封锁是否影响或改善了圣地亚哥河上游262公里河段的地表水质量。将封锁期间收集的15个水质参数数据与2019年（封锁前）、2021年（解封后）以及此前11年（2009 - 2019年）获得的水平进行比较。与封锁前相比，封锁期间浊度、生化需氧量、化学需氧量、总悬浮固体、粪大肠菌群、耐热大肠菌群、硝酸盐、硫酸盐和铅的值下降了4 - 36%，而pH值、电导率、总氮和砷增加了0.3 - 21%，这表明由于工商业活动的暂时关闭，河流中的有机负荷有所减少。11年的比较估计pH值、总悬浮固体、化学需氧量、总氮、硫酸盐、硝酸盐和铅下降了0 - 38%。解封期的比较显示，除砷外，所有参数均显著上升了3 - 37%，突出了圣地亚哥河沿线恢复活动的潜在影响。与其他调查时间段相比，估计的水质指数表明封锁期间河水质量有短期改善。根据因子分析，影响河流水质的主要污染源是未经处理的生活污水、工业废水和农业废水。总体而言，我们的分析表明，新冠疫情封锁改善了圣地亚哥河的水质，为地方官员识别污染源以及更好地支持环境政策和水质改善计划奠定了基础。
在线版本包含可在10.1007/s12665-022-10430-9获取的补充材料。
