Authors : Z. Branes , M. Ounissi , D. Sargos and C. Amblard
Abstract: The Oubeira Lake constitutes a vast extent of fresh water (5436 acre) of a maximal depth of 5m. Exploited for the irrigation, the drinking water and the extensive raising of 9 fish of which the silvery eel and the microphage species of Carps. This lake is considered as one of the biggest RAMSAR sites of Algeria (36�50`N, 8�23`E). The composition and the biomass of the phytoplankton have been analyzed monthly in three stations of the Oubeira Lake during a yearly cycle (October 2000-September 2001) in addition to the environmental parameters. The water temperature varied all along the months between 9 and 30 �C, the pH between 6.1 and 7.9, whereas the conductivity remained in the order of 1 mS. Unusually, the year 2001 was very little rainy with only 575 mm. The phytoplankton is formed mainly by the Cyanobacteria, Chlorophycea, Diatoms and in a least measures Euglenophycea. This basic population develops active densities up to 4�105 ind.L 1. The monthly middle biomass is 203 �g CL 1. This stock is made largely of the Cyanobacteria (32.5%) Chlorophyceae (27.1%) Diatoms (24.6%) and the Euglenophyceae (15.6%). The biomass reflects an important fertility and represents a wealth of the Oubeira
Z. Branes , M. Ounissi , D. Sargos and C. Amblard , 2007. Density and Biomass of Phytoplankton in the Oubeira Lake (North-East Algeria). Journal of Fisheries International, 2: 200-206.