Sediment transport connectivity and its response in the fluvial ecosystem detected with high-resolution data

The sediment transport is crucial for maintaining a good ecological condition of the aquatic ecosystem. Moreover, the study of sediment transport requires multitemporal and multiscale approaches using more sophisticated tools, such as precise imaging and generation of novel 3D technology, calculation elevation model, tracer particles analyses, ground-penetrating radar recording, grain size analyses etc. Consequently, transitioning from local to catchment scale, using high-resolution topography datasets, is the main challenge for system linkage identification using numerical methods and an exhaustive inventory of processes involved in the sediment cascade. The sediment bedload transport monitoring and analyses of spatio-temporal variability of this process were studied in the natural, braided-wandering river system of the Belá River with a multi-channel planform. High-resolution data collection from UAV (Unmanned Aerial Vehicle) and TLS (Terrestrial Laser Scanning) will be used for detailed topographic model and point cloud generation. Channel bathymetry was calculated from drone imagery and field inventory depth data. Historical aerial photographs were used for long-term channel adjustment and represent the horizontal extent of sedimentation with the impact of vegetation cover. Historical analyses have shown that pattern dynamics activate channel-floodplain movement and initiate a sediment cascade. Sediment supply to the channels correlates with the magnitude of flood events (maximum discharge, cumulative discharge, cumulative discharge higher than RI_1.5, and duration of discharges higher than RI_1.5) and lateral migration is the main factor controlling system. During the one specific reach survey from March 2016 to November 2018, were transported 10,103 m³ (25,964 tonnes) of fine-grained sediment into the river channel and intensive bed incisions accelerated into the channel bedrock.