Role of self-cleaning factors in river water environmental capacity assessment: A case of Sai Gon basin, Vietnam

Abstract

River water environmental capacity (RWEC) is an essential indicator of sustainable development. However, there are several studies on the dependence of RWEC on hydrological and hydraulic factors, especially self-cleaning ability. This study aims to clarify the role of self-cleaning factors in RWEC formation in a specific river basin. The method used in this study employed a set of models, including hydrological and eco-hydrodynamic models, with an added set of water quality parameters. The proposed research framework was applied to a specific river basin for four selected pollutants: NH4+, NO3-, PO43-, and BOD. The results revealed that the self-cleaning factors contributed significantly to the increase in RWEC. Specifically, RWECNH4+ improved by 22.6 % in the wet season and 22.7 % in the dry season; RWECNO3- improved by 10.22 % and 13.08 % in the wet and dry seasons, respectively; RWECPO43- exhibited the most significant improvement (143 % and 73 %, respectively), RWECBOD in the dry season decreased slightly by about 9%, the wet season increased by 88.34%. Our results demonstrate the critical role of self-cleaning factors in improving the carrying capacity, leading to developing medium- and long-term plans to preserve ecosystems in river systems in different basins.

Keywords

• RWEC
• Water quality
• Hydrodynamic
• Hydrological
• Ecological models