International audienceSuperficial and cored sediment samples from theMoulay Bousselhamlagoon and sub-watershedwere analyzedfor Al, Fe, Cu, Zn, Pb, Mn, Ni, Cr, As, Hg, and Cd. Thetemporal and spatial distributions of the main contaminationsources of heavy metals were identified and described usingchemometric and geographic information system (GIS) methods.Sediments from coastal lagoons near urban and agriculturalareas are commonly contaminated with heavy metals,and the concentrations found in surface sediments are significantlyhigher than those from 50–100 years ago. The concentrationsof these elements decrease sharply with depth in thesediment column, and the elements are preferentially enrichedin the <2-μm-sized fraction of the sediment. T...