Phytoplankton Biodiversity and Its Relationship with Aquatic Environmental Factors in Lake Sidi Mhamed Benali of the Wilaya of Sidi Bel Abbes (North-West of Algeria)

Abstract

Our work consists in characterizing the phytoplanktonic biodiversity of lake Sidi Mhamed Benali, also, biotic parameters were employed to assess lake trophic conditions, by Multivariate Analysis and by the ecological indices, during the period which extends from March to May 2021.The results of the phytoplankton analysis allowed us to list 89 species divided into 6 classes (Diatoms, Chlorophyceae, Euglenophyceae, Cyanophyceae, Cryptophyceae and Dinophyceae).The general composition of the phytoplankton of the lake is dominated by Diatoms with 34 taxa, or 36.62% of the phytoplankton community, represented mainly by the following genera: Cyclotella, Nitzschia and Fragilaria, followed respectively by Chlorophyceae with 25 taxa, or 31.81% of the total population, they are represented mainly by Oocystis, Tetraspora and Closterium, Eugenophyceae with 13 taxa, a proportion of 12. 82%, the Cryptophyceae: groups 5 taxa, with a proportion of 10.44%, the Cyanophyceae: counts 9 taxa, with a proportion of 6.88%, the Dinophyceae which groups 3 taxa, with a proportion of 1.42%. Moreover, the waters of the lake are classified as waters of average quality and are in as hypereutrophic state.