Suspended and Bedded Sediments
Aquatic Stressors
Impairments to aquatic systems can be induced by both suspended and bedded sediment. Sediments suspended in the water column of coastal wetlands, estuaries, and near-shore zones decrease light penetration and thereby cause undesirable shifts in communities of algae, invertebrates, and fish. Bedded sediments, those that have settled out and lie on the bottom of a water body of interest, physically alter the habitat of macroinvertebrates and algae leading to a shift in the fish community from generalist feeding and spawning fish to more bottom-oriented, silt- and turbidity-tolerant fish1. To address these issues, it is necessary to address the soil erosion and changes in land use that are causing increases in the amount of sediment delivered into our Nation's waters.
EPA's research to address the problems associated with suspended and bedded sediments begins with a through review of the scientific literature. The goal of this endeavor is to assess scientists' current level of understanding of the effects of this stressor on aquatic systems. EPA plans to focus special attention on developing a tool box of approaches that the States can use to derive suspended and bedded criteria for different water bodies. Specific models are now being developed to predict biological responses to the adverse effects of suspended and bedded sediments and to develop classification schemes that will facilitate the development criteria for this stressor.
View information about the Implementation Plan for Suspended and Bedded Sediment Research within the Aquatic Stressors PDF file. (PDF, 197 pp, 3.21 MB, About PDF).
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