The transport and resuspension of sediments in a shallow lake

Abstract

The time‐dependent flow and dispersion of suspended sediments in the western basin of Lake Erie are being studied by means of numerical models utilizing data from remote‐sensing studies and flume experiments. Mechanisms of sediment dispersion included in the models are convection and turbulent diffusion, river loading, gravitational settling, and physical resuspension and deposition at the sediment‐water interface. The time‐dependent currents are computed by means of a free surface hydrodynamic model. A wave‐hindcasting model is used to compute the wave parameters needed for estimation of shear stress generated at the sediment‐water interface under given wind conditions. The rate of sediment resuspension as a function of bottom shear stress and sediment properties is based on data from flume experiments using lake sediments. A series of numerical calculations with the models were performed on a two‐dimensional lake with a variable bottom representing a transverse cross section of Lake Erie. It was found that wind direction and fetch length can significantly affect the sediment dispersion patterns. The two‐dimensional and the three‐dimensional models were both used to simulate realistic short‐term events in Lake Erie, and the model outputs compare favorably with the synoptic surface sediment dispersion patterns deduced from the multispectral scanner data.

Spatiotemporal Variation of Turbidity Based on Landsat 8 OLI in Cam Ranh Bay and Thuy Trieu Lagoon, Vietnam

“…In the present study, owning to the lack of data on wave field and bottom roughness in the study site, f is assumed to have a constant value of 0.004 [41]. The description of adopted model parameters and computational conditions is presented in Table 3.…”

Three‐dimensional hydrodynamic and sediment transport modeling to test the sediment focusing hypothesis in upland lakes

“…Second, efforts have been made to improve the dynamic basis of the sediment focusing model. These have mostly involved modeling of wave-driven redistribution of sediment from shallow to deeper water (e.g., Sheng and Lick 1979;Bengtsson and Hellstr€ om 1992;L€ ovstedt and Bengtsson 2008). Rowan et al (1992) quantified the mud deposition boundary depth and used this to determine the locate and optimize the number of cores needed to estimate mean sedimentation rates (Rowan et al 1995).…”

“…Values for the critical stresses for erosion (s crit ) and deposition (s critd ); the erosion rate constant (d E ) and porosity (P o ) were obtained from a synthesis of the literature (including Sheng and Lick 1979;Bengtsson and Hellstr€ om 1992;Chao et al 2008). Model output included hourly values of suspended sediment concentration (SSC) at every location within the computational mesh, and the net erosion or deposition at every location at the bed.…”

Multiple Modeling Approach for the Aquatic Effects Assessment of a Proposed Northern Diamond Mine Development

“…The first system predicted wave geometry for a single wind storm on the lake by applying classic forecasting equations for waves in shallow water, as presented in U.S. Army Corps of Engineers (1984). Second, the model used equations developed by Sheng and Lick (1979) to predict wave-induced resuspension of bed sediment. Finally, TSS concentrations estimated using these equations were input into the GEMSS hydrodynamic module of the nutrient and DO model to simulate dispersion and settling of TSS.…”