Copepod assemblages as a bioindicator of environmental quality in three coastal areas under contrasted anthropogenic inputs (Gulf of Gabes, Tunisia)

The study of copepod assemblages indicated the presence of 22 species and 12 families in the southern coast of Sfax, 20 species and 13 families in the northern coast and 14 species and 8 families in the Ghannouch area, with a dominance of Oithonidae (79, 51 and 43% in the southern, northern and Ghannouch coasts, respectively). The relative abundance and the richness diversity of Oithonidae were found to be the most relevant indicators of anthropogenic pollution. Oithona nana, Euterpina acutifrons and Acartia clausi differed significantly in abundance between these three areas under differing degrees of pollution. The study of the structure, composition and density of the copepod fauna showed that the southern coast was a pollution-resistant ecosystem (H′ = 1.49 ± 0.33 bits ind−1; 22 species; density = 51.375 ± 4.340 × 103 ind m−3) followed by Ghannouch area (H′ = 1.74 ± 0.28 bits ind−1; 15 species; density = 11.979 ± 5.651 × 103 ind m−3) and the northern coast, considered as a restored area (H′ = 1.95 ± 0.26 bits ind−1; 21 species; density = 6.516 ± 4.304 × 103 ind m−3). The three ecosystems can thus be classified according to their degree of resistance to the anthropogenic inputs based on the results of the physico-chemical parameters and the species diversity as follows: southern coast > Ghannouch area > northern coast.

Diversity and Copepods’composition off Moroccan Atlantic Coast (Northwest Africa): A Review

This overview sums up the results of main investigations and knowledge about zooplankton off Moroccan Atlantic coast. Copepods diversity, spatial distribution, seasonal variability and hydrology off Moroccan Atlantic coast are given. A compilation of taxonomic list of copepods’ species found therein was established from published studies, they accounted for 210. Diversity and richness varied strongly between seasons, an onshore offshore gradient was observed as well. Species composition differed from northern to southern Moroccan Atlantic coast although most dominant species off Morocco’s coasts were Calanus helgolandicus, Paracalanus parvus, Acartia clausi and Corycaeus typicus. In addition, the largest number of species was found in upwelling regions. A synthesis study was established in order to spatial distribution of copepods along Moroccan Atlantic coast. The Factorial Correspondence Analysis of copepod species characterizing the most important sectors has shown different patterns of copepods distribution across Moroccan Atlantic coast; three main areas were clearly segregated according to their taxonomic composition (Northern, Central and Southern Atlantic).