Multi-temporal analysis of sediment source areas and sediment connectivity in the Rio Cordon catchment (Dolomites)

Marco Cavalli (a), Paolo Tarolli (b), Giancarlo Dalla Fontana (b) & Lorenzo Marchi (a)
(a) Research Institute for Geo-Hydrological Protection, National Research Council, Corso Stati Uniti 4, 35127, Padova, Italy. E-mail: marco.cavalli@irpi.cnr.it (b) Department of Land, Environment, Agriculture and Forestry, University of Padova, Via dell'Università 16, 35020, Legnaro, Italy.

In this study, two sediment source inventories produced in 1994 and 2006 have been compared and an analysis of sediment connectivity has been carried out in a 5 km2 headwater catchment (Rio Cordon catchment, Eastern Italian Alps). The 2006 sediment sources inventory was produced through an integrated approach encompassing field survey and interpretation of geomorphometric parameters (i.e., openness, surface roughness and wetness index) computed on a LiDAR-derived 1-m resolution DTM. The 2006 inventory aimed at updating a sediment source dataset dating back to 1994, which had been implemented by means of traditional techniques, i.e., field survey and interpretation of aerial photographs. Moreover, a topography-based index of connectivity (Cavalli et al., 2013) has been applied in order to evaluate the potential connection of 2006 sediment source areas with regard to the channel network. The analysis indicates that using a geomorphometric approach based on high-resolution LiDAR DTM in combination with field survey helps obtaining reliable and detailed sediment sources inventory and improving sediment delivery assessment.

sediment source areas, sediment connectivity, LiDAR, DTM, multitemporal analysis.