Combining limnology and paleolimnology : a refined understanding of environmental sediment signal formation in a varved lake
Paleoclimatic archives, such as lake sediments, extend our understanding of terrestrial and aquatic ecosystem dynamics in relation to climate variability beyond the period covered by instrumental data. In this context, annually laminated (i.e. varved) lake sediments are particularly valuable, as the...
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Umeå universitet, Institutionen för ekologi, miljö och geovetenskap
2017
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ftumeauniv:oai:DiVA.org:umu-135231 2023-10-09T21:54:36+02:00 Combining limnology and paleolimnology : a refined understanding of environmental sediment signal formation in a varved lake Maier, Dominique Béatrice 2017 application/pdf http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-135231 eng eng Umeå universitet, Institutionen för ekologi, miljö och geovetenskap Umeå : Umeå University http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-135231 urn:isbn:978-91-7601-603-9 info:eu-repo/semantics/openAccess varved lake sediments diatom sediment signal formation sequential sediment trap seasonal process timing ice thinning varve compaction climate impact catchment properties Earth and Related Environmental Sciences Geovetenskap och miljövetenskap Doctoral thesis, comprehensive summary info:eu-repo/semantics/doctoralThesis text 2017 ftumeauniv 2023-09-22T13:49:55Z Paleoclimatic archives, such as lake sediments, extend our understanding of terrestrial and aquatic ecosystem dynamics in relation to climate variability beyond the period covered by instrumental data. In this context, annually laminated (i.e. varved) lake sediments are particularly valuable, as they offer high temporal resolution and undisturbed sediment. However, in order to extract reliable climate information from lake sediments, a careful calibration with the processes controlling the sediment formation is essential. This thesis combines limnological and paleolimnological data from a varved, boreal lake in northern Sweden (Nylandssjön, Nordingrå) collected over different time scales. The main aim of the thesis is to gain a more refined insight into which processes are reflected in the sedimentary diatom assemblage. More specifically, sequential sediment trap records were coupled with physical, chemical and biological lake monitoring and environmental data for comparison and validation with the varved sediment record. The main result of the thesis is that timing, succession and inter-annual variability of key limnological and environmental processes (e.g. ice-cover duration, lake over-turn or catchment run-off) are of major importance for the sedimentary diatom assemblage formation. Continuous monitoring of physico-chemical parameters over three consecutive years identified varying winter air temperature as a major factor influencing in-lake processes and hence the diatom record. Timing of lake over-turn and catchment run-off seemed to be the driver for monospecific diatom blooms, which are reflected in the annual sediment signal. The integrated annual diatom signal in the sediment was dominated by spring or autumn blooms, resulting either from a Cyclotella glomerata dominated spring bloom after relatively warm winter conditions, or a Asterionella formosa dominated autumn bloom after relatively cold winter conditions. The analysis of the diatom stratigraphy in the varved sediment over several decades ... Doctoral or Postdoctoral Thesis Northern Sweden Umeå University: Publications (DiVA) Boreal Lake ENVELOPE(-127.670,-127.670,58.802,58.802) |
institution |
Open Polar |
collection |
Umeå University: Publications (DiVA) |
op_collection_id |
ftumeauniv |
language |
English |
topic |
varved lake sediments diatom sediment signal formation sequential sediment trap seasonal process timing ice thinning varve compaction climate impact catchment properties Earth and Related Environmental Sciences Geovetenskap och miljövetenskap |
spellingShingle |
varved lake sediments diatom sediment signal formation sequential sediment trap seasonal process timing ice thinning varve compaction climate impact catchment properties Earth and Related Environmental Sciences Geovetenskap och miljövetenskap Maier, Dominique Béatrice Combining limnology and paleolimnology : a refined understanding of environmental sediment signal formation in a varved lake |
topic_facet |
varved lake sediments diatom sediment signal formation sequential sediment trap seasonal process timing ice thinning varve compaction climate impact catchment properties Earth and Related Environmental Sciences Geovetenskap och miljövetenskap |
description |
Paleoclimatic archives, such as lake sediments, extend our understanding of terrestrial and aquatic ecosystem dynamics in relation to climate variability beyond the period covered by instrumental data. In this context, annually laminated (i.e. varved) lake sediments are particularly valuable, as they offer high temporal resolution and undisturbed sediment. However, in order to extract reliable climate information from lake sediments, a careful calibration with the processes controlling the sediment formation is essential. This thesis combines limnological and paleolimnological data from a varved, boreal lake in northern Sweden (Nylandssjön, Nordingrå) collected over different time scales. The main aim of the thesis is to gain a more refined insight into which processes are reflected in the sedimentary diatom assemblage. More specifically, sequential sediment trap records were coupled with physical, chemical and biological lake monitoring and environmental data for comparison and validation with the varved sediment record. The main result of the thesis is that timing, succession and inter-annual variability of key limnological and environmental processes (e.g. ice-cover duration, lake over-turn or catchment run-off) are of major importance for the sedimentary diatom assemblage formation. Continuous monitoring of physico-chemical parameters over three consecutive years identified varying winter air temperature as a major factor influencing in-lake processes and hence the diatom record. Timing of lake over-turn and catchment run-off seemed to be the driver for monospecific diatom blooms, which are reflected in the annual sediment signal. The integrated annual diatom signal in the sediment was dominated by spring or autumn blooms, resulting either from a Cyclotella glomerata dominated spring bloom after relatively warm winter conditions, or a Asterionella formosa dominated autumn bloom after relatively cold winter conditions. The analysis of the diatom stratigraphy in the varved sediment over several decades ... |
format |
Doctoral or Postdoctoral Thesis |
author |
Maier, Dominique Béatrice |
author_facet |
Maier, Dominique Béatrice |
author_sort |
Maier, Dominique Béatrice |
title |
Combining limnology and paleolimnology : a refined understanding of environmental sediment signal formation in a varved lake |
title_short |
Combining limnology and paleolimnology : a refined understanding of environmental sediment signal formation in a varved lake |
title_full |
Combining limnology and paleolimnology : a refined understanding of environmental sediment signal formation in a varved lake |
title_fullStr |
Combining limnology and paleolimnology : a refined understanding of environmental sediment signal formation in a varved lake |
title_full_unstemmed |
Combining limnology and paleolimnology : a refined understanding of environmental sediment signal formation in a varved lake |
title_sort |
combining limnology and paleolimnology : a refined understanding of environmental sediment signal formation in a varved lake |
publisher |
Umeå universitet, Institutionen för ekologi, miljö och geovetenskap |
publishDate |
2017 |
url |
http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-135231 |
long_lat |
ENVELOPE(-127.670,-127.670,58.802,58.802) |
geographic |
Boreal Lake |
geographic_facet |
Boreal Lake |
genre |
Northern Sweden |
genre_facet |
Northern Sweden |
op_relation |
http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-135231 urn:isbn:978-91-7601-603-9 |
op_rights |
info:eu-repo/semantics/openAccess |
_version_ |
1779318254094778368 |