Authors:
H. Bergayou
1
;
E. Anajjar
1
;
L. Lefrère
1
;
A. Moukrim
1
;
E. Gorman
2
and
P. Gillet
2
Affiliations:
1
Laboratory Aquatic Systems: Marine and Continental Environment (AQUAMAR), Team Biology, Ecology and Development of Marine Resources , Faculty of Sciences, Ibn Zohr University, B.P. 8106, 80000, Agadir, Morocco
;
2
Center for Studies and Research on Aquatic Ecosystems, Institute of Applied Ecology, UCO, BP 808, 44, rue Rabelais, 49008 Angers 01, France
Keyword(s):
Biomass, Estuary, Macrobenthos, Macrofaunal assemblage, Specific richness, Wastewater.
Abstract:
The communities of benthic macroinvertebrates, living in the estuary of Oued Souss (Agadir Bay, Morocco), were studied in parallel with the changes that this ecosystem had underwent after the stopping of pollution caused by untreated wastewater discharges. The specific richness was greater in the year following the end of discharges (22 species in 2003 instead of 11 found during the pollution period (2001-2002). A similar finding was noted for the dominance of the species. Indeed, if the dominating species was Hydrobia ulvae during the pollution period, followed by Hediste diversicolor and Scrobicularia plana in decreasing order, the sequence: H. diversicolor > H. ulvae >Cerastoderma edule > S. plana, was noted in 2003. The longitudinal distribution of species living in this site in 2001 and 2002 had wider in 2003 and average biomass, determined by the study of the ash-free dry weight, had become clearly greater.