Trakya University, Laboratory Technology Department, İpsala, Edirne, Turkey.
Malatya Turgut Özal University, Doğanşehir Vahap Küçük Vocational School, Department of Aquaculture, Malatya, Turkey.
Environ Res. 2021 Jun;197:111051. doi: 10.1016/j.envres.2021.111051. Epub 2021 Mar 19.
The surface water resources in the Meriç-Ergene River Basin, especially Ergene River and Çorlu Stream are among the most polluted rivers in Turkey. Despite the action plans for prevention and control of surface water pollution in the basin, the desired results have not been achieved. However, the implementation of a nationwide lockdown due to the COVID-19 might probably lead to an improvement in the surface water quality. We evaluated the impact of the lockdown on water quality by measuring the levels of physico-chemical variables and metal(loid)s in water samples taken from 25 sampling stations in the basin. BOD, COD, EC, turbidity, TSS and Mn levels did not show significant differences between the pre-lockdown and lockdown periods due to the ongoing domestic wastewater discharges and agricultural activities in the basin during the lockdown period. However, Cr, Ni, Zn, Cu, As, Pb and Cd concentrations decreased considerably during the lockdown. Similarly, heavy metal pollution index and heavy metal evaluation index values showed a significant improvement in water quality of almost all stations during the lockdown period. Also, total hazard index values for children and adults reduced by 67% and 69%, respectively during the lockdown period, while total carcinogenic risk values for As and Cr reduced by 60% and 94%, respectively. The limited operational status of most industrial facilities in the basin during the lockdown reduced the amount of industrial effluents, leading to significant improvement in surface water quality for metal(loid)s. The lockdown has shown that the solution for preservation and sustainability of natural water resources lies in our hands, and the efficient management of pollution sources can prevent surface water pollution at a very rapid pace. Finally, we suggest that water management policy needs to be improved and implemented.
梅里克里杰恩河流域的地表水资源，特别是杰恩河和乔鲁河，是土耳其污染最严重的河流之一。尽管流域地表水环境污染防治行动计划已经实施，但并未取得预期效果。然而，由于 COVID-19 的全国性封锁，地表水水质可能会得到改善。我们通过测量取自该流域 25 个采样点的水样中的理化变量和金属（类）含量，评估了封锁对水质的影响。由于封锁期间流域内仍有生活污水排放和农业活动，BOD、COD、EC、浊度、TSS 和 Mn 水平在封锁前后没有显著差异。然而，Cr、Ni、Zn、Cu、As、Pb 和 Cd 浓度在封锁期间大幅下降。同样，重金属污染指数和重金属评价指数在封锁期间几乎所有站点的水质都有显著改善。此外，封锁期间儿童和成人的总危害指数分别降低了 67%和 69%，而 As 和 Cr 的总致癌风险值分别降低了 60%和 94%。由于封锁期间流域内大多数工业设施的运营有限，工业废水排放量减少，导致金属（类）地表水水质显著改善。封锁表明，保护和可持续利用自然资源的解决方案掌握在我们手中，有效管理污染源可以非常迅速地防止地表水受到污染。最后，我们建议改进和实施水资源管理政策。
