Recent geomorphological changes of the middle and lower Calore River (Campania,Southern Italy)

The geomorphological changes experienced by the middle and lower Calore River (Southern Italy) between1957 and 1998 were investigated. Data derived from field surveys and interpretation of topographic maps and aerialphotos were introduced into a geographic information system (GIS) and processed. The results showed that the CaloreRiver underwent a mean narrowing of 66 %, with a peak of 86 %. The channel length increased by approximately 75 mand the sinuosity from1.311 to 1.314. The extension of fluvial bars reduced by more than 83 %, while their numberincreased from 151 to 381. Field evidence of riverbed lowering, such as river terraces formed in the considered timespan and exhumation of foundations of bridges and floodwalls, were also constantly detected. Due to these channeladjustments, the Calore River morphology changed from transitional to single-thread. These results were coherent withthose reported in the pre-existing literature about channel adjustments experienced by many rivers during the twentiethcentury. They all were explainable with a reduction of the bedload transport; this latter, in turn, is completely in accordance with the environmental changes that affected the Calore River system in the considered period (i.e., damming and/or channelization of the main tributaries, reduction of liquid discharge due to water withdrawals and sediment mining from the riverbed).