Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rapid environmental responses to climate-induced hydrographic changes in the Baltic Sea entrance
Stockholm University, Faculty of Science, Department of Geological Sciences.ORCID iD: 0000-0002-4768-9832
Show others and affiliations
Number of Authors: 62019 (English)In: Biogeosciences, ISSN 1726-4170, E-ISSN 1726-4189, Vol. 16, no 19, p. 3835-3852Article in journal (Refereed) Published
Abstract [en]

The Öresund (the Sound), which is a part of the Danish straits, is linking the marine North Sea and the brackish Baltic Sea. It is a transition zone where ecosystems are subjected to large gradients in terms of salinity, temperature, carbonate chemistry, and dissolved oxygen concentration. In addition to the highly variable environmental conditions, the area is responding to anthropogenic disturbances in, e.g., nutrient loading, temperature, and pH. We have reconstructed environmental changes in the Öresund during the last ca. 200 years, and especially dissolved oxygen concentration, salinity, organic matter content, and pollution levels, using benthic foraminifera and sediment geochemistry. Five zones with characteristic foraminiferal assemblages were identified, each reflecting the environmental conditions for the respective period. The largest changes occurred around 1950, when the foraminiferal assemblage shifted from a low diversity fauna dominated by the species Stainforthia fusiformis to higher diversity and abundance and dominance of the Elphidium species. Concurrently, the grainsize distribution shifted from clayey to sandier sediment. To explore the causes of the environmental changes, we used time series of reconstructed wind conditions coupled with large-scale climate variations as recorded by the North Atlantic Oscillation (NAO) index as well as the ECOSMO II model of currents in the Öresund area. The results indicate increased changes in the water circulation towards stronger currents in the area after the 1950s. The foraminiferal fauna responded quickly (<10 years) to the environmental changes. Notably, when the wind conditions, and thereby the current system, returned in the 1980s to the previous pattern, the foraminiferal assemblage did not rebound. Instead, the foraminiferal faunas displayed a new equilibrium state.

Place, publisher, year, edition, pages
2019. Vol. 16, no 19, p. 3835-3852
National Category
Earth and Related Environmental Sciences
Identifiers
URN: urn:nbn:se:su:diva-175816DOI: 10.5194/bg-16-3835-2019ISI: 000489054500002OAI: oai:DiVA.org:su-175816DiVA, id: diva2:1371699
Available from: 2019-11-20 Created: 2019-11-20 Last updated: 2019-11-20Bibliographically approved

Open Access in DiVA

No full text in DiVA

Other links

Publisher's full text

Search in DiVA

By author/editor
Schenk, FrederikFilipsson, Helena L.
By organisation
Department of Geological Sciences
In the same journal
Biogeosciences
Earth and Related Environmental Sciences

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf