Lagrangian analysis of bed-load sediment motion: database contribution

The purpose of the present note is to contribute to analysis of bed-load transport processes within a Lagrangian framework. Experiments were performed tracking individual particles under different bed conditions (mobile and fixed beds) at transitional hydrodynamic regimes. A new image processing procedure was designed to obtain the coordinates of each moving sediment within the intermediate range of scales (corresponding to a particle trajectory between rests periods). Thorough attention has been paid to provide consistent definitions for particle motion and trajectory, as well as to devise a rigorous method for analysis. A data set with properties of more than 4000 intermediate trajectories was obtained. Collected data were used to estimate stream-wise and transversal length and duration of intermediate trajectories and corresponding mean sediment velocities. Statistical significance of the values obtained for measured properties was ascertained by appropriate analysis. The full data set is provided with the manuscript as supplementary material.