Nelson, J. R.. Skidaway Institute of Oceanography, nelson@skio.peachnet.edu
Robertson, C. R.. Skidaway Institute of Oceanography, charles@skio.peachnet.edu

 
BIO-OPTICAL VARIABILITY AND THE POTENTIAL FOR BENTHIC PRIMARY PRODUCTION ON THE CONTINENTAL SHELF OF THE SOUTH ATLANTIC BIGHT
 
Across much of the continental shelf of the South Atlantic Bight (SAB), the euphotic zone often extends to the sediment surface. The potential for benthic primary production at mid-shelf depths will be strongly influenced by optical filtering in the overlying water column (affecting the intensity and spectral quality of irradiance reaching the sediments), the biomass of benthic microalgae in surface sediments, and their photosynthetic capacity. This study investigates seasonal patterns of hydrographic and bio-optical variability in the mid-shelf water column and how this affects irradiance at the sediment surface and benthic primary production. A combination of ship sampling, SeaWiFS imagery, and laboratory studies of the photosynthesis-irradiance (P-E) response of benthic microalgae is employed. Application of the k490 product of SeaWiFS to estimate PAR flux to the shelf sea floor on a regional scale is considered, in particular with regard to seasonal changes in hydrographic structure and sources of bio-optical variability on the shelf. In addition to demonstrating the adjustment of P-E responses of benthic microalgae in surface sediments to ambient irradiance, laboratory studies indicate a rapid recovery of photosynthetic capability for subsurface (buried) cells upon exposure to simulated in situ light.
 
Day: Friday, Feb. 5
Time: 10:30 - 10:45am
Location: Eldorado Hotel
 
Code: SS46FR1030E