Résumé:
The marine coastal ecosystems of Mostaganem, like those of the entire Mediterranean coast, are
fragile, vulnerable, limited and coveted. These are environments increasingly affected by human
activities, by the increase in urban density at the coast, which discharges its discharges into coastal
marine waters, and which cause intense ecological pressure on these environments. To this end,
several bioindicators derived from benthic macrofauna are widely used in the evaluation and
monitoring of the quality of the marine environment in order to counter this degradation of the
environment.
It is in this context that this study falls. It is based on the evaluation and identification of the
benthic macrofauna of the rocky substrates of the Mediolittoral stage of the coastal zone of the
Wilaya of Mostaganem. Thus, three sites were chosen to know: Stidia, Kharouba and Hadjadj. The
assessment of the ecological quality of these different sites was carried out using biological indices
such as: statistical descriptors (Specific Wealth (S), Abundance (A), Dominance) and diversity indices
[Shannon Wiener Index ( H ') and equilibrium index of Piélou (J')]. So we chose to test the
environmental quality of these different sites, using the larval development test of the sea urchin
Paracentrotus lividus, a species widely used for this type of analysis.
The analysis of the composition of benthic settlements as well as the tests of the quality of the
larval development of the sea urchin Paracentrotus lividus revealed and confirmed a satisfactory
general state of the three sites studied. However, the site of Kharouba, seems to present a stand
much more characterized by an organization in equilibrium compared to the sites of Stidia and
Hadjadj.