ASSESSMENT OF THE PHYSICO CHEMICAL AND BIOLOGICAL QUALITY OF THE OURIKA CATCHMENTYASSINE SCHAHRAKANE, HANANE IDALI, NAAIMA BENJELOUN, ABDELATIFE KHATABI, WAHBI ABDERRAZIK AND OUADIA TAZIAbstract The present work has for object the study of the physico-chemical parameters including some heavy metals (Lead, Cadmium and Zinc) as well as the benthic component, at the level of the Ourika River, to determine the state of pollution of the area and its impact on public health. Sampling was carried out in seven areas of the basin for the biological and heavy metals study and at eleven zones for the physico-chemical study. The choice of these areas is mainly related to accessibility and socio-economic activities near each zone. The physicochemical study showed, values exceeding the norms with a maximum of 619.8 ìS.cm-1 for conductivity, 1.108 mg.L-1 for orthophosphate, 1.985 mg.L-1 for ammoniacal nitrogen , 0.99 mg.kg-1 for cadmium, 104.75 mg.kg-1 for Zinc (substrate samples) and 0.08 mg.kg-1 for Lead (water samples). The biological study, meanwhile, revealed an average water quality for the indexes Global Normalized Biological and the Ephemeroptere Plecoptere trichoptere index and a low quality (polluted) for the riparian band quality index. Following these results, good monitoring and management of these resources is necessary to preserve its biodiversity and the health of its local population. |