The Impact of Environmental Factors on the Diaphanosoma sp Distribution in Ghrib Lake (Northern Algeria)

On the basis of zooplanktonic materials collected during the sampling period at Ghrib Lake (June 2014–May 2015), two species belonging to the genus Diaphanosoma were identified; D. brachyurum Liévin and D. orghidani Negrea. This later (D. orghidani) was harvested for the first time in Algeria. Some physicochemical parameters such as the temperature of surface water, pH, dissolved oxygen, salinity, conductivity, and nutrients were also evaluated. The distribution of the abundance of both species in the lake is not even and varies from season to season, it depends mainly on the environmental factors, and the originality of its composition depends on water quality. The abundance of D. orghidani presented higher values mainly in the summer (71% in the cladoceran community) and lower in late autumn. On the contrary, the abundance of D. orghidani increased in autumn.