Author(s): Mohamad Nasr; Adele Johannot; Thomas Geay; Sebastien Zanker; Alain Recking

Linked Author(s): Thomas Geay, Alain Recking

Keywords: Bedload transport; Passive acoustics; Hydrophone

Abstract: Bedload transport drives river morphology evolution and influences its ecological value and the stability of hydraulic structures. The spatiotemporal variability of bedload transport in addition to high forces associated with major flood events make direct sampling of bedload transport very challenging. Recently, surrogate technologies have been developed to monitor bedload transport. In this research, we deal with passive acoustic monitoring of bedload self-generated noise (SGN) using a hydrophone deployed in the water. Several previous studies have correlated bedload flux to the bedload SGN. We will particularly consider the calibration curve obtained by Geay et al. (2020), relating the specific bedload flux to cross-section-averaged acoustic power. This calibration curve was fitted on a field dataset comprising 25 experiments of direct bedload sampling and acoustic measurements obtained in 14 different river reaches. We followed the same protocol and produced 14 additional experiments. The newly measured specific bedload fluxes range from 1 g/s/m up to 2000 g/s/m covering a new range of values not present in the calibration data set. The new data have confirmed the calibration curve.

DOI: https://doi.org/10.3850/IAHR-39WC252171192022778

Year: 2022