Erosion Of Fine-grained Sediments Research Articles

Effects of salinity and particle concentration on sediment hydrodynamics and critical bed-shear-stress for erosion of fine grained sediments used in wetland restoration projects

Abstract. Sea-level rise, the increasing number and intensity of storms, oil and groundwater extraction, and coastal land subsidence are putting people and property at risk along Louisiana’s coast, with major implications for human safety and economic health of coastal areas. A major goal towards re-establishing a healthy and sustainable coastal ecosystem has been to rebuild Louisiana’s disappearing wetlands with fine grained sediments that are dredged or diverted from nearby rivers, channels and lakes to build land in open water areas. A thorough geo-hydrodynamic characterization of the deposited sediments is important in the correct design and a more realistic outcome assessment of the long-term performance measures for ongoing coastal restoration projects. This paper evaluates the effects of salinity and solid particle concentration on the re-suspension characteristics of fine-grained dredged sediments obtained from multiple geographic locations along the Gulf coast. The critical bed-shear-stress for erosion has been evaluated as a function of sedimentation time. The sediment hydrodynamic properties obtained from the laboratory testing were used in a numerical coastal sediment distribution model to aid in evaluating sediment diversions from the Mississippi River into Breton Sound and Barataria Bay.

石狩湾沿岸域における細粒土砂の移動特性について

A three-dimensional hydrodynamic Princeton Ocean Model was used to compute the suspended particulate matter (SPM) transport in Ishikari Bay from February to March 2002. The sources of SPM were the input of the Ishikari River and the erosionof fine-grained sediment by stress of wave-driven and wind-driven currents in this model. The model can represent the turbidity in the coastal station of the depth 25m in Ishikari Bay. The model results show that fine-grained sediment suspended by bottom stress caused by a strong wind and high wave are moving to the southern area and the coastal area of Otaru with the characteristic costal currents in winter.