Streamwise and Vertical Dispersal of Tracer Stones in an Equilibrium Bed

Modeling transport, erosion, and deposition of nonuniform sediment over temporal intervals that are short compared to those characterizing channel bed aggradation degradation remains an open problem due the complex quantification fluxes between material load alluvial deposit. Parker, Paola, Leclair in 2000 proposed a morphodynamic (PPL) framework overcome this problem. This is used here model dispersal patch gravel tracers three different settings, laboratory flume, mountain creek, braided river. To simplify problem, (a) slope, bedload transport rate, configuration assumed be constant space time (equilibrium), (b) entrainment modeled with step length formulation, (c) PPL implemented one-dimensional (laterally averaged) model. Model validation against experiments suggests that, as capacity flow increases, maximum elevation-specific density may migrate downward The comparison results field data shows equilibrium solution can reasonably capture tracer dispersal. also reproduce subdiffusion superdiffusion streamwise direction, depending on magnitude short-term level changes. Finally, average elevation cross-section decreases because particles buried deep deposit only rarely reentrained into transport.