Contribution à l'étude bio écologique de l'ichtyofaune de Sebkhet El-Maleh (Ghardaïa)

Abstract

Our study is devoted to the bioecological characterization of both biotic and abiotic elements in the El- Goléa Lake or Sebkhet El-Maleh aquatic environment of the Ghardaia region located in the northern Algerian Sahara. We determined in both lake and study drain sites the physicochemical quality of the water. The results obtained indicate that the waters of the two sampling sites (lake and drain) are characterized by a temperature is related to the temperature of the air, slightly alkaline pH with a high electrical conductivity. They are also brackish water rich in dissolved oxygen. The ichthyological inventory allowed the identification of 3 species of fish belonging to 2 families: Tilapia zillii, Tilapia sp (Cichlids), Gambusia affinis (Poeciliidae). The meristic characteristics of the four fish studied vary little according to sex. The allometric type determination for ichthyofauna growth studies was carried out by demonstrating the evolution of the various metric variables with total length (LT). The results obtained show that 66 % of these traits follow isometric growth in G. affinis. The sex ratio is in favor of males for both of females. On the other hand, size at first sexual maturity is reached in males before females; the breeding period is fractionated over time. It is very intense during the warm period.