HR: 11:35h
AN: OS12A-06    [Abstracts]
TI: Contrasting inherent optical properties and carbon metabolism between five northeastern (USA) estuary-plume systems.
AU: * Vandemark, D
EM: douglas.vandemark@nasa.gov
AF: NASA/GSFC, Bldg. N-159, Wallops Island, VA 23337 United States
AU: Salisbury, J
AF: Univ. of New Hampshire, Morse Hall, Room 142, Durham, NH 03824 United States
AU: Hunt, C
AF: Univ. of New Hampshire, Morse Hall, Room 142, Durham, NH 03824 United States
AU: McGillis, W R
AF: Columbia University, LDEO, New York, NY 10027 United States
AB: We have recently developed the ability to rapidly assess surface inherent optical properties (IOP), oxygen concentration and pCO2 in estuarine-plume systems using flow-through instrumentation. During the summer of 2004, several estuarine-plume systems were surveyed which include the Pleasant (ME), Penobscot (ME), Kennebec-Androscoggin (ME), Merrimack (NH-MA) and Hudson (NY). Continuous measurements of surface chlorophyll and colored dissolved organic carbon (CDOM) fluorescence, beam attenuation, temperature, salinity, oxygen and pCO2 were taken at each system along a salinity gradient from fresh water to near oceanic endmembers. CTD and IOP profiles were also taken at predetermined surface salinity intervals. These were accompanied by discrete determinations of chlorophyll (HPLC and fluorometric), total suspended solids (TSS), dissolved organic carbon (DOC) and alkalinity. IOP data were calibrated using chlorophyll, DOC and TSS data to enable the retrieval of these constituents from IOP data. Considerable differences in the data sets were observed between systems. These ranged from the DOC-enriched, strongly heterotrophic Pleasant River System to the high-chlorophyll autotrophic Merrimack River System. Using pCO2 and oxygen saturation measurements as proxies for water column metabolism, distinct relationships were found between trophic status and inherent optical properties. The nature of these relationships varies between systems and is likely a function of watershed and estuarine attributes including carbon and nutrient loading, in-situ production and related autochthonous inputs of DOC and alkalinity. Our results suggest that IOP data may contain significant information about the trophic status of estuarine and plume systems.
DE: 4815 Ecosystems, structure and dynamics
DE: 4847 Optics
DE: 1615 Biogeochemical processes (4805)
DE: 1640 Remote sensing
DE: 0312 Air/sea constituent fluxes (3339, 4504)
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting