Visar resultat 1 - 5 av 20 avhandlingar innehållade ordet foraminifera.
1. Arctic Ocean benthic foraminifera preservation and Mg/Ca ratios : Implications for bottom water palaeothermometry
Sammanfattning : Reconstructions of Arctic Ocean palaeotemperatures are needed to disentangle natural variability from anthropogenic changes and understand the role of ocean heat transport in forcing or providing feedbacks on Arctic climate change. Despite known complications with calcareous microfossil preservation in Arctic Ocean sediments, calcareous benthic foraminifera can be common in interglacial sequences. LÄS MER
Sammanfattning : Ocean acidification, mainly attributed to the increasing anthropogenic CO2 in the atmosphere, is characterised by a lowering pH together with a shift in the sea water carbonate chemistry toward lower concentration of carbonate ions. On the coasts, where the environmental variability is high due to natural and human impacts, ocean acidification mainly affects the frequency, magnitude, and duration of lower pH and lower calcium carbonate saturation events. LÄS MER
Sammanfattning : The central Arctic Ocean is one of the least explored deep sea regions and long biostratigraphic sediment records are sparse. The main focus of this thesis is the Arctic Ocean foraminiferal record and its application to reconstruct paleoceanographic variations and summer sea ice cover changes between late Quaternary interglacial periods. LÄS MER
Sammanfattning : Deoxygenation, i.e. loss of oxygen from the oceans, often considerably influences the aquatic organisms and the wholeecosystem and changes biogeochemical cycles. It results in increasing bottom areas of hypoxia (. LÄS MER
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