Evaluation of the Impact of Anthropic Activities on the Physico-Chemical and Microbiological Parameters of the Water of the Wadi Inaouene and Its Tributaries

Abstract

Water is a basic human requirement that is required in many processes, particularly those performed in households. However, in most circumstances, this critical product does not fulfill commonly recognized safety criteria. Various anthropogenic activities cause various forms of pollution; as a result, their physicochemical and biological components can pose major hazards to the environment and human health. The objective of this research was to evaluate the microbiological parameters along the Inaouene wadi and its tributaries, as well as their correlation with the physicochemical characteristics. In spring 2020, the following physicochemical and microbiological studies were conducted: ICP-AES was used to assess metals. The most polluted stations are located upstream (S1, S3, S4, S5, and S6). The highest concentrations of sulfate, orthophosphate, BOD5, and nitrogen compounds are found at these stations. Illegal solid and liquid discharges from the tributaries S1 and S5, as well as urban settlements built on the banks of the Inaouen River, are to blame for this pollution, which has a direct and significant impact on water quality throughout the wadi. Furthermore, heavy metals (Zn, Fe, Co, Cr, Ag, and Cu) are abundant upstream of Inaouen and pass downstream. The monitoring of the evolution of microbiological pollution of wastewater has revealed a significant contamination of these waters upstream of the Wadi by the 3 groups of germs indicative of a fecal contamination and the presence of Listeria monocytogenes and salmonella in the upstream stations and especially S1, S3 and S5. The PCA revealed that the indicator bacteria of fecal contamination present negative correlations with dissolved oxygen, thus the lack of dissolved oxygen leads to a proliferation of germs in the water.