Nutrients and water masses in the Gulf of Maine - Georges Bank region: Variability and importance to blooms of the toxic dinoflagellate Alexandrium fundyense
We report here the results of ten oceanographic survey cruises carried out in the Gulf of Maine - Georges Bank region of the Northwest Atlantic during the late spring to summer period in 2007, 2008 and 2010, for which we examine and characterize relationships among dissolved inorganic nutrient field...
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ftpubmed:oai:pubmedcentral.nih.gov:4448144 2023-05-15T17:45:47+02:00 Nutrients and water masses in the Gulf of Maine - Georges Bank region: Variability and importance to blooms of the toxic dinoflagellate Alexandrium fundyense Townsend, D.W. McGillicuddy, D.J. Thomas, M.A. Rebuck, N.R. 2014-05-01 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4448144/ https://doi.org/10.1016/j.dsr2.2013.08.003 en eng http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4448144/ http://dx.doi.org/10.1016/j.dsr2.2013.08.003 Article Text 2014 ftpubmed https://doi.org/10.1016/j.dsr2.2013.08.003 2015-05-31T00:10:34Z We report here the results of ten oceanographic survey cruises carried out in the Gulf of Maine - Georges Bank region of the Northwest Atlantic during the late spring to summer period in 2007, 2008 and 2010, for which we examine and characterize relationships among dissolved inorganic nutrient fields, water mass dynamics and cell densities of the toxic dinoflagellate Alexandrium fundyense. Nutrients are supplied to continental shelf waters of the Gulf of Maine - Georges Bank region by inflows of deep offshore water masses; once in the Gulf they are transported with the residual circulation and mix with surface waters, both in the Gulf and on the Bank. Those fluxes of offshore water masses and their nutrient loads are the major source of nutrients for phytoplankton production in the region, including annual blooms of A. fundyense in the Gulf and on Georges Bank. This much is already known. We suggest here that the locations and magnitude of A. fundyense blooms are controlled in part by variable nutrient fluxes to the interior Gulf of Maine from offshore, and, those interior Gulf of Maine waters are, in turn, the main nutrient source to Georges Bank, which are brought onto the Bank by tidal pumping on the Northern Flank. We present evidence that nitrate is the initial form of nitrogenous nutrient for A. fundyense blooms, but it is quickly depleted to limiting concentrations of less than 0.5 μM, at which time continued growth and maintenance of the population is likely fueled by recycled ammonium. We also show that phosphate may be the limiting nutrient over much of Georges Bank in summer, allowing recycled ammonium concentrations to increase. Our temperature-salinity analyses reveal spatial and temporal (seasonal and interannual) variability in the relative proportions of two deep source waters that enter the Gulf of Maine at depth through the Northeast Channel: Warm Slope Water (WSW) and Labrador Slope Water (LSW). Those two source waters are known to vary in their nutrient loads, with nitrate concentrations ... Text Northwest Atlantic PubMed Central (PMC) Deep Sea Research Part II: Topical Studies in Oceanography 103 238 263 |
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Article Townsend, D.W. McGillicuddy, D.J. Thomas, M.A. Rebuck, N.R. Nutrients and water masses in the Gulf of Maine - Georges Bank region: Variability and importance to blooms of the toxic dinoflagellate Alexandrium fundyense |
topic_facet |
Article |
description |
We report here the results of ten oceanographic survey cruises carried out in the Gulf of Maine - Georges Bank region of the Northwest Atlantic during the late spring to summer period in 2007, 2008 and 2010, for which we examine and characterize relationships among dissolved inorganic nutrient fields, water mass dynamics and cell densities of the toxic dinoflagellate Alexandrium fundyense. Nutrients are supplied to continental shelf waters of the Gulf of Maine - Georges Bank region by inflows of deep offshore water masses; once in the Gulf they are transported with the residual circulation and mix with surface waters, both in the Gulf and on the Bank. Those fluxes of offshore water masses and their nutrient loads are the major source of nutrients for phytoplankton production in the region, including annual blooms of A. fundyense in the Gulf and on Georges Bank. This much is already known. We suggest here that the locations and magnitude of A. fundyense blooms are controlled in part by variable nutrient fluxes to the interior Gulf of Maine from offshore, and, those interior Gulf of Maine waters are, in turn, the main nutrient source to Georges Bank, which are brought onto the Bank by tidal pumping on the Northern Flank. We present evidence that nitrate is the initial form of nitrogenous nutrient for A. fundyense blooms, but it is quickly depleted to limiting concentrations of less than 0.5 μM, at which time continued growth and maintenance of the population is likely fueled by recycled ammonium. We also show that phosphate may be the limiting nutrient over much of Georges Bank in summer, allowing recycled ammonium concentrations to increase. Our temperature-salinity analyses reveal spatial and temporal (seasonal and interannual) variability in the relative proportions of two deep source waters that enter the Gulf of Maine at depth through the Northeast Channel: Warm Slope Water (WSW) and Labrador Slope Water (LSW). Those two source waters are known to vary in their nutrient loads, with nitrate concentrations ... |
format |
Text |
author |
Townsend, D.W. McGillicuddy, D.J. Thomas, M.A. Rebuck, N.R. |
author_facet |
Townsend, D.W. McGillicuddy, D.J. Thomas, M.A. Rebuck, N.R. |
author_sort |
Townsend, D.W. |
title |
Nutrients and water masses in the Gulf of Maine - Georges Bank region: Variability and importance to blooms of the toxic dinoflagellate Alexandrium fundyense |
title_short |
Nutrients and water masses in the Gulf of Maine - Georges Bank region: Variability and importance to blooms of the toxic dinoflagellate Alexandrium fundyense |
title_full |
Nutrients and water masses in the Gulf of Maine - Georges Bank region: Variability and importance to blooms of the toxic dinoflagellate Alexandrium fundyense |
title_fullStr |
Nutrients and water masses in the Gulf of Maine - Georges Bank region: Variability and importance to blooms of the toxic dinoflagellate Alexandrium fundyense |
title_full_unstemmed |
Nutrients and water masses in the Gulf of Maine - Georges Bank region: Variability and importance to blooms of the toxic dinoflagellate Alexandrium fundyense |
title_sort |
nutrients and water masses in the gulf of maine - georges bank region: variability and importance to blooms of the toxic dinoflagellate alexandrium fundyense |
publishDate |
2014 |
url |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4448144/ https://doi.org/10.1016/j.dsr2.2013.08.003 |
genre |
Northwest Atlantic |
genre_facet |
Northwest Atlantic |
op_relation |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4448144/ http://dx.doi.org/10.1016/j.dsr2.2013.08.003 |
op_doi |
https://doi.org/10.1016/j.dsr2.2013.08.003 |
container_title |
Deep Sea Research Part II: Topical Studies in Oceanography |
container_volume |
103 |
container_start_page |
238 |
op_container_end_page |
263 |
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