Achievement of a good performance in a Direct Numerical Simulation (DNS) of a particulate flow has been restricted to a low particle Reynolds number below a few hundreds due to the limitation of computational load by using a fine grid (Harada and Gotoh, 2008). Hence, in this study, to perform numerical simulations in higher particle Reynolds numbers, a Large Eddy Simulation (LES) by Smagorinsky...

Channel bifurcations can be found in river network systems from high gradient gravel-bed rivers to fine-grained low deltas. In these systems, often evolve asymmetrically such that one downstream channel silts up and the other deepens and, most cases, they eventually avulse. Past analytical numerical studies showed symmetric are unstable Shields stress conditions resulting asymmetric avulsion, w...

The need for accurate modeling of rainfall-runoff-sediment processes has grown rapidly in the past decades. This study investigates the efficiency of black-box models including Artificial Neural Network (ANN) and Autoregressive Integrated Moving Average with eXogenous input (ARIMAX) models for forecasting the rainfall-runoff-sediment process. According to the complex behavior of the rainfall-ru...

We investigate the use of the short-lived fallout radionuclide beryllium-7 ( Be; t1/2 = 53·4 days) as a tracer of medium and coarse sand (0·25–2 mm), which transitions between transport in suspension and as bed load, and evaluate the effects of impoundment on seasonal and spatial variations in bed sedimentation. We measure Be activities in approximately monthly samples from point bar and stream...

Coastal systems are increasingly threatened by multiple local anthropogenic and global climatic stressors. With the difficulties in remediating global stressors, management requires alternative approaches that focus on local scales. We used manipulative experiments to test whether reducing local stressors (sediment load and nutrient concentrations) can improve the resilience of foundation speci...

An innovative approach was developed to reveal phosphorus (P) transport and redistribution in large and complex river networks in the Lake Taihu basin by establishing the relations between sediment P spatial distribution and P sorption behavior on particles with different grain size, sorted by hydrodynamics. The sediment P fractionation composition changed greatly across the basin, where 69% co...

This paper presents results of a 3 year pilot study of surface erosion on forest roads in the Jackson Demonstration State Forest in California’s coastal redwood region. Ten road segments representing a range of surface, grade, and ditch conditions were selected for the study. At each segment, settling basins with tipping buckets were installed to measure coarse sediment and total runoff. Labora...

background: this study aimed to evaluate the pollution levels of surface water with heavy metals including pb, cd and cr in gheshlagh river, western iran. methods: water and sediment were sampled in five monitoring stations with three replicates in time along the river. the concentration of cr, pb and cd in both water and sediment samples were measured with graphite furnace atomic absorption sp...