Multiyear Monitoring of an Experimental Watershed and Seismic Modeling of Bedload Transport in Gravel-Bed Alluvial Channel

We first present a comprehensive dataset of five-year monitoring of an experimental watershed at the Arroyo de los Pinos in the central New Mexico.We measured bedload flux directly by mechanical samplers, and seismic signals by seismometers located outside the channel.We then applied a physics-based model of Tsai et al. (2012) to estimate bedload flux to an ephemeral channel with gravel-bed alluvium active on the riverbed.Due to the discrepancy between model predictions and field observations, we further incorporated modifications to better estimate bedload flux in this environment.We altered the statistical distributions of bedload impact frequency, velocity, and angle to account for rolling and sliding and to account for inelastic bed impacts.The modified model decreased error relative to observations to less than one order of magnitude.Although we obtained a good agreement between model predictions and observations, further investigations are needed in other environmental contexts to demonstrate the robustness and broad applicability of the modified model.