Aquatic Sciences Meeting, Albuquerque 2001

SS35 Biological and Ecological Responses to Low Oxygen in Constant and Fluctuating Environments (Spatial and Temporal Connections)

Date: Thursday, February 15, 2001, Time: 3:00:00 PM

Location: La Cienega

Shiller, A, M, University of Southern Mississippi, Stennis Space Center, USA, alan.shiller@usm.edu

USING TRACE ELEMENT DISTRIBUTIONS TO ESTIMATE BOTTOM RECYCLED NUTRIENT FLUXES ON THE LOUISIANA SHELF

Oxygen depletion is seasonally observed in the bottom waters of the Louisiana Shelf. This oxygen depletion probably results from a stimulation of primary production by anthropogenic nutrients from the Mississippi and Atchafalaya Rivers as well as from stratification due to the input of the river water to the shelf. Some shelf productivity is undoubtedly supported by nutrients remineralized in bottom waters. This includes recycling of particulate organic materials settling from the surface waters and particulate nutrients from the rivers. Estimating this flux of nutrients from the bottom back into the surface waters is an important unknown quantity in the shelf biogeochemical cycle. The distributions of dissolved V and Mn may be useful in understanding bottom nutrient recycling processes because the bottom sediments are a sink for V and a source for Mn. A box model interpretation of shelf trace element data indicates a flux of nutrients from bottom waters into shelf surface waters that is of a similar magnitude to the fluvial nutrient flux and a substantial off-shelf transport of nutrients with the shelf bottom waters.

This Session Listing

Aquatic Sciences Meeting, Albuquerque 2001

Quicklinks