Choix du site de culture de l'algue rouge Gracilaria verrucosa (Hudson) papenfuss dans la lagune de Bizerte : Caracteristiques physico-chimiques de l'eau.

Abstract

Water physico-chemical characteristics : Environmental characterization of different depths and site representing the biogeochemical differences of the Bizerte lagoon, north of Tunisia, was done in order to select a site and depth for the culture of the red algae Gracilaria verrucosa. The concentration and distribution of nutrient (ammonium, phosphate) in water, as well as the salinity, temperature and dissolved oxygen was studied along three sampling stations at different depths (1, 2, 3 and 4 m), during a spring 2009 in order to know their spatial and temporal variations. Standardized analytical methods were applied in order to reach these objectives. The use of soils for farming and continental runoff of the adjacent terrestrial systems close to the coastal lagoon seemed to be a significant nutrient source for this water body. During this period, we noticed the absence of all stratification horizontal and vertical concerning the various studied parameters.