Keywords:
Hochschulschrift
Description / Table of Contents:
Benthic foraminifera, stable isotopic composition, NAO, Skagerrak, deep-water renewal, microhabitat effect, vital effect, d13C, d18O. - Two Holocene sediment cores from the southern flank of the Skagerrak are investigated for the stable oxygen and carbon isotopic composition of benthic foraminiferal tests and faunal assemblages. Core 225514 was recovered from 420 m and Core 225510 from 285 m water depth. The stable oxygen isotopic composition of Bulimina marginata tests in Core 225514 is demonstrated to indicate Skagerrak deep-water renewal during the last 1200 years. Since deep-water renewal is characterized by sudden drops in temperature and salinity, and since δ18O values reflect both temperature and salinity changes, the influences of the two parameters have to be evaluated separately. By comparing the measured δ18O variability with a salinity-δ18O mixing line valid for marine to brackish Scandinavian waters, it was shown that salinity changes are responsible for maximal 9 % of the total δ18O variability. Correlation of temperature monitoring data with the North Atlantic Oscillation (NAO) index reveals that Skagerrak deep-water renewal is triggered by the negative phase of the NAO. During highly negative index phases very cold and calm conditions prevail over the North Sea. Central North Sea water masses are cooled down strongly and hence reach densities, which are higher than those of the deep Skagerrak water masses. Occasionally, these dense water masses start to cascade into the Skagerrak. The stable carbon isotopic composition of benthic foraminiferal tests is used to investigate the organic matter flux to the seafloor and the oxygen availability ...
Type of Medium:
Online Resource
Pages:
Online-Ressource
Edition:
2008 Online-Ausg.:
Series Statement:
Berichte zur Polar- und Meeresforschung 572
URL:
http://hdl.handle.net/10013/epic.28879
URL:
http://nbn-resolving.de/urn:nbn:de:gbv:46-diss000109893
URL:
http://elib.suub.uni-bremen.de/diss/docs/00010989.pdf
URL:
http://d-nb.info/997391057/34
URL:
http://nbn-resolving.de/urn:nbn:de:gbv:46-diss000109893
URL:
http://nbn-resolving.de/urn:nbn:de:101:1-201102182849
URL:
http://d-nb.info/1010115057/34
URL:
http://hdl.handle.net/10013/epic.28879.d001
URN:
urn:nbn:de:gbv:46-diss000109893
URN:
urn:nbn:de:101:1-201102182849
DDC:
550
Language:
English
Note:
Parallel als Buch-Ausg. erschienen
,
Zugl.: Bremen, Univ., Diss., 2007
,
Online-Ausg.:
Permalink