Ecosystem trend and evolution in fluvial morphology: an example in Calabria

The basin management is steered towards a global approach where engineering and naturalistic techniques complement each other, supporting the natural trend of continental waterways until a stable equilibrium longtime. In this sense, the river, regarded as "hydro-system", extends from riverbed to bordering areas, known as peri-fluvial strips. This approach is particularly important in the morphological study of fluvial systems, located in anthropic areas. The fluvial morphology or, in other words, the whole of different shapes showed by rivers, develops on time under the action of different factors, human actions included, and it occurs as a "continuum" of structures without any boundaries between them. Mollard suggested in 1973 a morphological classification based on photo-interpretation that compares the linear forms with some factors as the solid transport at the bottom of rivers, the relationship between this kind of transport and the whole solid transport, the grain size and some physical/territorial factors, as the slope and the winding of riverbed. This study aims to analyze the evolutional trend of Crati river in a stretch of about 15 Km. between Luzzi and Bisignano towns through a comparative methodology that collates the fluvial morphology at different ages with a particular care to riverbed variations, owing to natural or anthropic events. Besides, together with the morphological analysis of riverbed, it has been applied in the catchment of Crati river an environmental and synthetic method, named Fluvial Functionality Index (IFF), to value the whole ecological status of the basin.