METAL EXCHANGES IN THE FAUNA-SEDIMENT SYSTEM - THE CASE OF NEREIS-DIVERSICOLOR AND SCROBICULARIA-PLANA IN THE BOU REGREG ESTUARY (MOROCCO)

This study identifies the types and quantities of metals retained by Nereis diversicolor and Scrobicularia plana in a predominantly arid estuary environment. Certain abiotic parameters and a number of physiological processes linked to metabolic and reproductive functions play a decisive role in the seasonal influence of metal levels on the tissues of these organisms. Given the deposivoric diet of the organisms, the sedimentary bed would appear to be the principal source of metal accumulation. The following classification illustrates the bioaccumulation of metals: [GRAPHICS] The possibility that these metals may be carried into the estuary by sewage water from the cities of Rabat and Sale should certainly not be ignored.