File Download

There are no files associated with this item.

  Links for fulltext
     (May Require Subscription)
Supplementary

Article: Recent eutrophication and consequent hypoxia in the bottom waters of the Lower St. Lawrence Estuary: Micropaleontological and geochemical evidence

TitleRecent eutrophication and consequent hypoxia in the bottom waters of the Lower St. Lawrence Estuary: Micropaleontological and geochemical evidence
Authors
Keywordseutrophication
hypoxia
Lower St. Lawrence Estuary
dinoflagellate cysts
benthic foraminifera
geochemistry
Issue Date2006
Citation
Marine Geology, 2006, v. 231, n. 1-4, p. 37-50 How to Cite?
AbstractMicropaleontological and geochemical analyses were carried out on two sediment box cores (AH00-2220 and CR02-23) recovered in the Lower St. Lawrence Estuary (LSLE) in order to document recent temporal variations of primary productivity and carbon fluxes to the bottom waters. These reveal a ten-fold increase in the accumulation rate of dinoflagellate cysts and benthic foraminifera in the sediment over the last four decades which can be interpreted as a recent increase in pelagic and benthic production. Furthermore, the appearance of the benthic foraminiferal species Brizalina subaenariensis and Bulimina exilis, which are tolerant of low oxygen concentrations and high organic fluxes, in the upper 20 cm of the cores, may reflect significant changes in bottom water conditions over the last 40 yrs. Variations in the microfossil abundances in core AH00-2220 are strongly correlated with an increase in organic carbon (OC) content (from 1.1 to 1.6%) and to a shift in the isotopic signature of the latter (δ13CORG from - 24.8 to - 24.0‰). Similarly, a concomitant decrease in the CORG:N ratio (from 15 to 12), an increase in organic carbon content (from 1.3 to 1.9%) and an increase in δ13CORG (from - 24.5 to - 23.5‰) were observed in core CR02-23, all of which suggest an enhanced accumulation of marine over terrestrial OC in the LSLE. Our results imply that a significant increase in marine productivity in the LSLE occurred since the 1960's. © 2006 Elsevier B.V. All rights reserved.
Persistent Identifierhttp://hdl.handle.net/10722/210588
ISSN
2015 Impact Factor: 2.503
2015 SCImago Journal Rankings: 1.489

 

DC FieldValueLanguage
dc.contributor.authorThibodeau, Benoît-
dc.contributor.authorde Vernal, Anne-
dc.contributor.authorMucci, Alfonso-
dc.date.accessioned2015-06-19T01:49:28Z-
dc.date.available2015-06-19T01:49:28Z-
dc.date.issued2006-
dc.identifier.citationMarine Geology, 2006, v. 231, n. 1-4, p. 37-50-
dc.identifier.issn0025-3227-
dc.identifier.urihttp://hdl.handle.net/10722/210588-
dc.description.abstractMicropaleontological and geochemical analyses were carried out on two sediment box cores (AH00-2220 and CR02-23) recovered in the Lower St. Lawrence Estuary (LSLE) in order to document recent temporal variations of primary productivity and carbon fluxes to the bottom waters. These reveal a ten-fold increase in the accumulation rate of dinoflagellate cysts and benthic foraminifera in the sediment over the last four decades which can be interpreted as a recent increase in pelagic and benthic production. Furthermore, the appearance of the benthic foraminiferal species Brizalina subaenariensis and Bulimina exilis, which are tolerant of low oxygen concentrations and high organic fluxes, in the upper 20 cm of the cores, may reflect significant changes in bottom water conditions over the last 40 yrs. Variations in the microfossil abundances in core AH00-2220 are strongly correlated with an increase in organic carbon (OC) content (from 1.1 to 1.6%) and to a shift in the isotopic signature of the latter (δ13CORG from - 24.8 to - 24.0‰). Similarly, a concomitant decrease in the CORG:N ratio (from 15 to 12), an increase in organic carbon content (from 1.3 to 1.9%) and an increase in δ13CORG (from - 24.5 to - 23.5‰) were observed in core CR02-23, all of which suggest an enhanced accumulation of marine over terrestrial OC in the LSLE. Our results imply that a significant increase in marine productivity in the LSLE occurred since the 1960's. © 2006 Elsevier B.V. All rights reserved.-
dc.languageeng-
dc.relation.ispartofMarine Geology-
dc.subjecteutrophication-
dc.subjecthypoxia-
dc.subjectLower St. Lawrence Estuary-
dc.subjectdinoflagellate cysts-
dc.subjectbenthic foraminifera-
dc.subjectgeochemistry-
dc.titleRecent eutrophication and consequent hypoxia in the bottom waters of the Lower St. Lawrence Estuary: Micropaleontological and geochemical evidence-
dc.typeArticle-
dc.description.natureLink_to_subscribed_fulltext-
dc.identifier.doi10.1016/j.margeo.2006.05.010-
dc.identifier.scopuseid_2-s2.0-33748325780-
dc.identifier.volume231-
dc.identifier.issue1-4-
dc.identifier.spage37-
dc.identifier.epage50-

Export via OAI-PMH Interface in XML Formats


OR


Export to Other Non-XML Formats