Aquatic Sciences Meeting, Albuquerque 2001

SS08 Processes at the Benthic Interface (Environmental Connections)

Date: Tuesday, February 13, 2001, Time: 9:45:00 AM

Location: Ruidoso/Pecos

Sanford, L, P, Univ. of Md. Ctr. for Environ. Sci., Horn Point Laboratory, Cambridge, MD, USA, lsanford@hpl.umces.edu

Chang, M, L, Md. Dept. of the Environ., Baltimore, MD, USA, mchang@mde.state.md.us

Porter, E, T, Univ. of Md. Ctr. for Environ. Sci., Chesapeake Biol. Lab., Solomons, MD, USA, porter@cbl.umces.edu

INFLUENCES OF RESUSPENSION-DEPOSITION CYCLING AND BOUNDARY LAYER DIFFUSION ON BENTHIC-PELAGIC COUPLING IN MUDDY ENVIRONMENTS

Sediment resuspension and boundary layer diffusion frequently are invoked as important physical controls on benthic-pelagic coupling in aquatic ecosystems. However, few studies have considered how the influences of these physical processes vary, and how they interact with biogeochemical processes in the surface sediments. In this presentation, we bring together results from recent theoretical, numerical, and mesocosm investigations to consider these questions, limiting ourselves to environments with fine, impermeable sediments. We show how the influences of resuspension and diffusion are enhanced for biogeochemical reactions concentrated at the interface and diminished for more diffuse reactions. We illustrate the influences of resuspension and subsequent deposition on recycling of newly sedimented material under both regular forcing and episodic forcing, considering coupling between resuspension and boundary layer diffusion and interactions with surface layer biogeochemistry. Finally, we consider interactions between resuspension, light limitation, microphytobenthos, and diffusion in an ecosystem context. Sediment porosity, biogeochemical reactivity, microphytobenthos biomass, and external sedimentation rate are revealed as important factors that interact with resuspension and diffusion to determine their influences on benthic-pelagic coupling.

This Session Listing

Aquatic Sciences Meeting, Albuquerque 2001

Quicklinks