La dinamica dell'alveo del Torrente Torre (Pianura Friulana) nel corso degli ultimi 200 anni

The study aims to reconstruct the channel changes of the Torre Torrent (Friulian Plain) in the last 200 years and to identify the causes of such changes. The research, focusing on a reach of 44 km in length (the whole reach in the alluvial plain up to the confluence with the Isonzo River), was carried out using historical maps, aerial photographs, cross-sections, and through field survey. The Torre Torrent has undergone dramatic channel adjustments, specifically narrowing (channel width reduction of 77 % in the braided reach) and incision (locally up to 8 m). The main causes of such adjustments have been gravel mining (very intense during the 1960s and 1970s) and channelization works (levees and groynes). The morphological evolution of the Torre Torrent is very similar to that of others Italian rivers, except for the most recent times. In fact, narrowing has been the dominant process along the Torre in the last 15-20 years, whereas channel widening has been very common in many other rivers in such time period.