Spatio-temporal pattern of bed sediments storage upstream from a large dam reservoir. The case of the gravel-bed Dunajec River and the Czorsztyn Reservoir, Polish Carpathian
In this study the impact of the base-level rising upstream from the Czorsztyn Reservoir (CR) constructed in 1997 on the gravel-bed Dunajec River (Polish Carpathian) on the pattern of bed sediments storage was reconstructed from the aerial photos and LiDAR data. The bed sediments area in CR backwater showed the above three-fold higher increasing than observed in the control section (not affected by backwater reservoir), in the first period after dam construction with large flood. The spatial pattern of the in-channel sediment storage was not related to the distance from reservoir but is explained by bank erosion and valley floor configuration. This study showed that reservoir-induced base-level rising promoted the bed sediments storage but spatio-temporal trajectory of this phenomena is related to the local valley characteristics and floods.