Seasonal Variation in Nutrients and Microalgal Community Composition in Mobile Bay, Alabama, and the Northern Gulf of Mexico (2007-2009)

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A transect was sampled from Mobile Bay, Alabama to 40 km offshore at monthly to bi-monthly intervals from March, 2007. Horizontal salinity gradients ranged from 8 to 18 PSU in surface waters. Temperature ranged from 16 to 32 C. Maxima in chlorophyll concentrations and total microalgae numbers were associated with maxima in nutrient concentration. Nutrient concentrations were in turn inversely correlated with salinity, indicating the importance of Mobile Bay as a source. The highest chlorophyll concentrations were found in July-August. The highest cell counts were found during a bloom of the dinoflagellate Prorocentrum minimum in March inside Mobile Bay. The community composition showed a seasonal succession from dinoflagellate- to diatom-dominance in spring, followed by mixed assemblages of chlorophytes, prasinophytes and cryptophytes in summer. There were also horizontal gradients, with dinoflagellate-dominance occurring only in Mobile Bay during the Prorocentrum. There were higher proportions of prasinophytes in Mobile Bay and higher proportions of chlorophytes offshore in the mixed-flagellate assemblage in summer.

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Author data@disl.org
Maintainer data@disl.org
Last Updated July 23, 2022, 03:04 (UTC)
Created July 23, 2022, 03:03 (UTC)
Access_Constraints Permission to access these data must be given by DISL Data Management.
ISO 19115 Topic Categories environment, oceans, biota
Place Keywords Alabama, Mobile Bay, Gulf of Mexico, Dauphin Island Sea Lab, DISL
Theme Keywords salinity, temperature, chlorophyll concentration, microalgae, nutrients, Bio-optics, absorption, scattering, attenuation, cell counts, cyanobacteria, prasinophytes, chlorophyte, cryptophyte, euglenophytes, chrysophytes, diatoms, dictyophytes, raphidophytes, algal bloom, community composition, abundance, dinoflagellate, assemblage, photosynthesis, phytoplankton, water quality, Chla, nitrogen, phosphorus, water column, diversity, density
Use_Constraints Acknowledgment of the DISL: Marine Microalgal Lab is required in products developed from these data, and such acknowledgment as is standard for citation and legal practices for data source is expected by users of these data. Users should be aware that comparison with other data sets for the same area from other time periods may be inaccurate due to inconsistencies resulting from changes in mapping conventions, data collection, and computer processes over time. The distributor shall not be liable for improper or incorrect use of these data, based on the description of appropriate/inappropriate uses described in the metadata document. These data are not legal documents and are not to be used as such.
dc.contributor Hugh MacIntyre and Lucie Novoveská-Brunden
dc.coverage.placeName Alabama Mobile Bay Gulf of Mexico Dauphin Island Sea Lab DISL
dc.coverage.t.max 20090716T
dc.coverage.t.min 20070306T
dc.coverage.x.max -88.0109
dc.coverage.x.min -88.2117
dc.coverage.y.max 30.4374
dc.coverage.y.min 29.7972
dc.creator DISL: Marine Microalgal Lab
dc.date Unpublished material
dc.description A transect was sampled from Mobile Bay, Alabama to 40 km offshore at monthly to bi-monthly intervals from March, 2007. Horizontal salinity gradients ranged from 8 to 18 PSU in surface waters. Temperature ranged from 16 to 32 C. Maxima in chlorophyll concentrations and total microalgae numbers were associated with maxima in nutrient concentration. Nutrient concentrations were in turn inversely correlated with salinity, indicating the importance of Mobile Bay as a source. The highest chlorophyll concentrations were found in July-August. The highest cell counts were found during a bloom of the dinoflagellate Prorocentrum minimum in March inside Mobile Bay. The community composition showed a seasonal succession from dinoflagellate- to diatom-dominance in spring, followed by mixed assemblages of chlorophytes, prasinophytes and cryptophytes in summer. There were also horizontal gradients, with dinoflagellate-dominance occurring only in Mobile Bay during the Prorocentrum. There were higher proportions of prasinophytes in Mobile Bay and higher proportions of chlorophytes offshore in the mixed-flagellate assemblage in summer.
dc.language en
dc.source FOCAL nutrient and microalgal data
dc.subject salinity temperature chlorophyll concentration microalgae nutrients Bio-optics absorption scattering attenuation cell counts cyanobacteria prasinophytes chlorophyte cryptophyte euglenophytes chrysophytes diatoms dictyophytes raphidophytes algal bloom community composition abundance dinoflagellate assemblage photosynthesis phytoplankton water quality Chla nitrogen phosphorus water column diversity density
dc.title Seasonal Variation in Nutrients and Microalgal Community Composition in Mobile Bay, Alabama, and the Northern Gulf of Mexico (2007-2009)
dc.type spreadsheet
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