Modeling sediment entrainment and transport processes limited by bed armoring

A sediment-transport model including a bed-armoring algorithm is used to ascertain the potential importance of bed-armoring processes. The parameters that control the bed-armoring effects on the suspension of granular sediments in the marine environment are examined using the numerical model and data from the Eel shelf. Results for the shelf indicate that bed armoring controls the total suspended-sediment load and affects the across-shelf gradients of suspended material. The armoring effects are too significant to be neglected in most analyses of shelf and nearshore sediment transport, and this is especially relevant for models that are developed to represent large-scale and long-term sedimentary regimes. A principal controlling parameter is the thickness of the active layer, and the dynamics of this layer are not well known. (C) 1999 Elsevier Science B.V. All rights reserved.