Evaluation of the impact of anthropogenic actions on the Nador lagoon (Morocco) by the index of the sediment pollution load

Résumé

In order to assess the degree of chemical contamination of the Nador Lagoon (NE Morocco), superficial sediment samples (0-10 cm) were collected at 28 points of the lagoon and the total heavy metal contents (Cu, Cd, Cr, Ni, Pb and Zn) were determined.

The spatial distribution of the pollutant load index (PLI) in the lagoon shows that the Merchica lagoon has a moderate degree of contamination (contaminated to moderately contaminated) except in areas close to Selouane, El Mrader, and El Bachir rivers, and the town of Beni Ensar where there is a severe contamination. This can be explained on the one hand by urban liquid discharges and the liquid discharges conveyed by these rivers and on the other hand by hydrocarbon discharges and the activities of the boats in the Beni Ensar area.