Bedload rates and bedload/suspended sediment relation in a stepped mountain channel under gulling process
Landscape position, high bedload flux, landscape degradation, equilibrium geometry channel.
Bedload transport data are scarce, need time and hard work to be sampled, and have different behaviors on landscape position, as in stepped mountain channels under the gulling process. Here, the bedload flux from a stepped mountain channel was perceived as a mass wave determined by the mass addition in the quantity relationship between bedload and suspended sediment originating from the gulling process in pulses. The bedload and suspended sediment flux were determined from a mountain channel in a small watershed under a current gulling process. The expressive gulling process is associated with the high sediment concentration and high bedload contribution to the total load between 41.4 to 77% under low discharges. Thus, the obtained bedload transport flux on the Liberdade channel did not follow hydraulic transport parameters but is described as a mass wave model. The Liberdade channel stability and geometry equilibrium were reached downstream with the streamflow in low Froude numbers.