ounissi makhlouf
Position: Full professor, Senior Research Officier
Organization: University of Annaba, Faculty of Science, Department of Marine Science, Po Box 1
Description: The Mellah lagoon is microtidal littoral ecosystem with a mean depth of 3m and a volume of about 25 Millions m3 and its surface is about 9km�. It function as a dilution basin and will be renewed two times a year. It is exployted mainly for migratory species fishing (sea bass, European Eel, Mullets, Bream bass) and molluscs extracting & rearing. The Mellah lagoon is a integral part of the El-Kala National Parc which is classified as resreve of the biosphere. The mafrag estuary is a microtidal ecosystem rises in the North East of Algeria. The lenght of the estuary part is about 20km and has a volume of about 4millions m3 and its water surface is close to 1.50Km�; the flow of the estuary at the mouth varies from 0m3/s in severe dry years to 500m3/s in flooding periods. It is a temporary salt wadge estuary strogly stratified in spring & in summer. In winter it functions as river while it becomes a core lagoon in autumn. It is a very atypic estuary by its hydrological regime and by its diversity of habitats including marshland, rivers, estuary, littoral plain, large underground water inputs. The hydrological is however disturbed by water retension in dams but remains unpolluted and functions as wild and virgin wetland. Fishing is reduced to sea bass, European Eel & carps cutchs. Carps species invades however the site from the contigueous hydrosystems in particular the Oubeira Lake. The Seybouse River discharges fluctuate between 0.5 and 2.5 milliars of m3 a year. It has a watershed of about 6,500km� populated by over 1.5 Millions inhabitants. Annually mean loading of Nitrogen is about 3,000 to 6,000 tons and 600 to 1,500 tons for phosphate. The gulf of Annaba is submitted to large nutrient transport from the seybouse river and the Mafrag estuary in spite of urban & industrial loading which contribute of about 50% of nutrients transporting to the gulf of Annaba. I'm collecting data on nutrient concentrations and loadings from that land sources since 2002 and hope inlarge our research to other algerian rivers.