Analysis of planimetric channel changes along the Cecina River (central Italy)

摘要

A Geographical Information System has been developed, and historical maps and aerial photographs of different scales and dates have been used to identify, measure and analyze planimetric channel changes. Channel width and sinuosity index have been measured.All the measurements have been used to analyze in detail the spatial and temporal trends in planimetric adjustments and ultimately to derive a conceptual evolution model illustrating the spatial and temporal trends of adjustments.Fluvial planimetric form undergoes continuous changes as a consequence of channel adjustments. These adjustments are the river response to variations in the balance between sediment supply and transport capacity.Channel changes may be caused by geomorphic response to natural changes, for example climate, or human impacts, including land use change as afforestation, dam construction, channelization work and sediment mining.