Zaneveld, J. V. Oregon State University, zaneveld@oce.orst.edu
Barnard, A. V. Oregon State University, abarnard@oce.orst.edu
Washburn, J. L. Oregon State University, washburj@ucs.orst.edu
Moore, C. WET Labs, Inc, casey@wetlabs.com

 
SMALL SCALE SPATIAL VARIATIONS IN BENTHIC INHERENT OPTICAL PROPERTIES: PRELIMINARY RESULTS FROM A DIVER OPERATED AC-9.
 
A diver-operated ac-9 was developed that allows the measurement of spectral absorption and attenuation coefficients in benthic environments. Water is sucked through a diver held tube into the ac-9, which is mounted on the diving pack of the diver. The pack also contains a battery pack, pump, and data recorder. Data was taken during the Coastal Benthic Optical Properties experiment at Lee Stocking Island in the Bahamas during May 1998. Data is presented that examines the effect of substrate, height above bottom, and the general environment on the absorption and attenuation spectra. Results showed that variations in absorption and attenuation coefficients of about a factor of two occur on scales of about 10 cm, but only near the bottom. These variations are not obviously related to substrate, which consisted of coral patches and sand bottom. They are more likely the result of small resuspension events. One meter above the bottom absorption and attenuation coefficients were less variable and approximately 20% lower. Absorption spectra showed little evidence of chlorophyll. Spectra looked like they were due to detritus (resuspended calcareous sand) and/or yellow matter. Spectra were steeper in eelgrass beds than over sand or coral bottoms, presumably because of the increased presence of yellow matter.
 
Day: Thursday, Feb. 4
Time: Poster
Location: Sweeney Center
 
Code: CS61TH0922S