2. Materials and mmethods
2.1 The studied system
The system under study consists of an inland farm specialized in intensive rearing of sea bream with a global production,capacity of 2500 tonnes per year. the major part of the production,about 70%,is exported to Europe and North America. The farm is located in the east cost of Tunisian in a region of Halk EI menjel to the north and a seaside resort to the south