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OAS accession Detail for 0117507, meta_version: 2. Current meta_version is: 8
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Title: Biological, physical, and chemical data collected from inshore and shelf surface waters in Alabama from Jul 2009 - Dec 2011 (NODC Accession 0117507)
Abstract: Abstract: Quantifying the linkages between primary production and higher trophic levels is necessary to understand why particular regions can support high fisheries production. Modified dilution experiments were employed to characterize microbial communities in surface waters at four sites from within a bay to the shelf in the northern Gulf of Mexico (nGOM). Inshore surface waters were more variable than shelf surface waters due to the strong influence of river discharge. Phytoplankton (Chl a) and prokaryote biomass were both significantly higher inshore than on the shelf, with phytoplankton significantly higher than prokaryotes inshore. Virus and heterotrophic nanoflagellate abundances, however, did not differ between inshore and shelf waters. Samples were amended with nutrients (N + P) to examine the impact of nutrient limitation. Prokaryotes were nutrient limited in 14 (28%) of the experiments, while phytoplankton were nutrient limitated in 26 (52%) of the experiments. When phytoplankton were nutrient limited, prokaryote growth rates were significantly altered. A similar impact on phytoplankton growth rates occurred when prokaryotes were nutrient limited, suggesting that the two groups are in competition for resources. Grazing was detected in the majority of experiments, while viral lysis was only detected in 24% of phytoplankton and 12% of prokaryote experiments. Growth and grazing rates for both phytoplankton and prokaryotes were tightly coupled inshore and on the shelf, with significantly more phytoplankton and prokaryotes grazed inshore (average = 106% and 75%, respectively) than on the shelf (average = 55% and 57%). These findings indicate that surface waters across the estuary are highly productive, with microzooplankton grazing transferring the majority of the microbial production to higher trophic levels.

Purpose: These experiments were designed to determine the relative roles of grazing and viral lysis on the microbial communities in Mobile Bay, AL.
Date received: 20140415
Start date: 20090701
End date: 20111201
Seanames: Coastal Waters of Alabama, Coastal Waters of Gulf of Mexico, Gulf of Mexico, North Atlantic Ocean
West boundary: -88.2116
East boundary: -88.0113
North boundary: 30.4374
South boundary: 29.79887
Observation types: biological, chemical, laboratory analyses, manual sample collection, physical, phytoplankton abundance, site samples, surface measurements
Instrument types: bottle, CTD, Flow Cytometer, fluorescence microscope, fluorometer, laboratory analysis, nutrient autoanalyzer
Datatypes: BIOMASS, BIOMASS - PLANKTON, CHLOROPHYLL A, Dissolved Organic Nitrogen, DISSOLVED OXYGEN, graze rate (or grazing rate), growth rate, MICROBIOLOGY, MICROPLANKTON, NANOPLANKTON, NITROGEN, NUTRIENTS, PHYTOPLANKTON, PHYTOPLANKTON BIOMASS, SALINITY, Silicon, WATER TEMPERATURE, ZOOPLANKTON BIOMASS
Submitter: Tzeng, Mimi
Submitting institution: Dauphin Island Sea Lab
Collecting institutions: Dauphin Island Sea Lab
Contributing projects: DWH
Platforms:
Number of observations:
Supplementary information: PI: Dr. Alice Ortmann
Availability date:
Metadata version: 2
Keydate: 2014-04-15 20:32:49+00
Editdate: 2014-04-16 17:00:39+00