Impact of anthropogenic activities on the physicochemical and bacteriological quality of water along Oued Fez River (Morocco)

The current study focuses, on Oued Fez, the tributary of Sebou River, the principal hydraulic artery of Fez city, to establish a spatiotemporal diagnosis from upstream to downstream. Samples were taken in 9 stations, distributed to areas with different activities (agricultural, urban and industrial), during three seasons, to evaluate the physicochemical parameters; temperature, pH, electrical conductivity (EC), dissolved oxygen (DO), turbidity, total dissolved substances (TDS), orthophosphate (PO 4 3 -), chemical oxygen demand (COD), biological oxygen demand (BOD 5 ), nitrates (NO 3 -), ammonium (NH 4 + ), nitrites (NO 2 -) and sulfate (SO 4 2 -). Bacteriological characterization of total aerobic microbial bacteria (TAMB), Staphylococcus aureus , Total coliforms (TC), and fecal coliforms (FC) of different samples, were carried out by standard methods. The results showed that the values of all parameters varied significantly ( p < 0.05), from upstream to downstream except for; PO 4 3 -, NO 3 -, NO 2 -, and SO 4 2 -. In addition, they exceeded Moroccan water standards of surface and those of the WHO, reflecting a deterioration in the water quality along the segment studied. The high values of the physicochemical indicators and the intense microbial load resulted from the anthropic activities associated with the industrial impacts generated by the agglomerations of Fez city and those who dwell along the river, leading to the affectation of the water quality. The results of this study can offer a crucial information to municipal water operators, local authorities, and decision-makers in finding an adequate environmental approach to limit the constraints on the site and protect the integrity of its ecosystem.(c) 2023 The Author(s). Published by Elsevier B.V. on behalf of African Institute of ( http://creativecommons.org/licenses/by-nc-nd/4.0/ )