Notes on coastal lagoon typology in the light of the EU Water Framework Directive: Italy as a case study

1. The European Water Framework Directive (WFD) requires that Member States differentiate the transitional water bodies into types. 2. WFD assigns coastal lagoons to two different water categories, transitional waters and coastal waters on the basis of freshwater influence. 3. The main physical factors that contribute to the genesis and characterization of coastal lagoons are coastal typology, tidal range and climate. 4. Italian lagoons are presented as an example of how these physical factors can be used in coastal lagoon characterization and typology. On this basis, a clear distinction of Italian lagoons into two main groups is possible: Northern Adriatic and Mediterranean. 5. Large lagoons can be profitably subdivided into a hierarchical system of sub-basins facilitating both the comparison of parts of the same lagoon and the comparison between different lagoons. 6. The basins are consistent water bodies that can be used as managerial units for environmental conservation, species protection and wise use of resources.