Does Local Resuspension Maintain the Benthic Nepheloid Layer in Southeastern Lake Michigan?

Abstract

Time-series observations of water temperature, water transparency, and current velocity at four stations in southeastern Lake Michigan show that the benthic nepheloid layer is probably not maintained by the local resuspension of bottom sediment. Local resuspension may occasionally occur in the deep parts of the lake, but it seems likely that vertical mixing and offshore advection of sediment-laden water maintain the benthic nepheloid layer during most of the year. Although sediment trap data have been interpreted as indicating that local resuspension does occur, it is more likely that the increased sediment fluxes observed near the bottom are due to vertical redistribution of material already in suspension.