“…The nature of bed load transport is highly stochastic and complex, even under steady state conditions, involving a wide range of spatiotemporal scales, from grain-scale kinematics to bed form-scale migration [Sekine and Parker, 1992;Papanicolaou et al, 1999;Ancey et al, 2006;Ancey, 2010;Hill et al, 2010;Singh et al, 2009Singh et al, , 2011Singh et al, , 2012Ramesh et al, 2011;Furbish et al, 2012a;McElroy and Mohrig, 2012;Julien and Bounvilay 2013;Guala et al, 2014;Keylock et al, 2014;Cristo et al, 2015]. This inherent stochasticity is mostly a result of the particle-fluid interactions and particle-particle interactions, leading to diffusion (also referred to as dispersion) of particles during their movement [Martin et al, 2012].…”