Main aim of the course is studying the inter¬relationships between physical and biological factors in streams, rivers, lakes and estuaries ecosistems. Syllabus Study of physical factors of importance to the biota. Physical and hydrological processes of the habitats and relative functions. Interation by the organisms that inhabit aquatic ecosistems, their adaptation, distribution and diversity. Basic principles of nutrient cycling, transport and trasformation. Food sources and energy flow. Role of uman activities in freshwater ecosistems and their effects. Monitoring methods of bioindication and Water Framework Directive.