Assessing the potential of the chrysophyte cyst Archaeomonas spp. as a sea ice proxy in the North Atlantic during the Holocene
Climate change and temperature rise in the Arctic is resulting in a decrease in sea ice extent and changes in sea ice variability. The impact of climate change on sea ice variability can be better understood when studying past events of climate change and sea ice extent change. Past environmental ch...
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Helsingin yliopisto
2023
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ftunivhelsihelda:oai:helda.helsinki.fi:10138/358752 2023-08-20T04:04:31+02:00 Assessing the potential of the chrysophyte cyst Archaeomonas spp. as a sea ice proxy in the North Atlantic during the Holocene Anna, Leppänen Helsingin yliopisto, Bio- ja ympäristötieteellinen tiedekunta University of Helsinki, Faculty of Biological and Environmental Sciences Helsingfors universitet, Bio- och miljövetenskapliga fakulteten 2023 application/pdf http://hdl.handle.net/10138/358752 eng eng Helsingin yliopisto University of Helsinki Helsingfors universitet URN:NBN:fi:hulib-202306132588 http://hdl.handle.net/10138/358752 sea ice diatom chrysophyte cyst Holocene North Atlantic Archaeomonas spp Ympäristömuutoksen ja globaalin kestävyyden maisteriohjelma (ECGS) Master's Programme in Environmental Change and Global Sustainability Magisterprogrammet i miljöförändringar och global hållbarhet Ympäristömuutos Environmental Change Miljöförändring pro gradu -tutkielmat master's thesis pro gradu-avhandlingar 2023 ftunivhelsihelda 2023-07-28T06:09:29Z Climate change and temperature rise in the Arctic is resulting in a decrease in sea ice extent and changes in sea ice variability. The impact of climate change on sea ice variability can be better understood when studying past events of climate change and sea ice extent change. Past environmental change can be reconstructed using bioindicators such as chrysophyte cysts, siliceous resting stages of chrysophyte algae. Archaeomonas spp., a genus of chrysophyte cyst, is often found preserved in Marginal Ice Zone sediments in the Arctic and its relationship with sea ice extent is explored here, to further understand its potential as a sea ice proxy. Diatom slides from three cores in the North Atlantic (Melville Bay, the North Water Polynya and Placentia Bay) were used to evaluate relationships between Archaeomonas spp. and known sea ice diatom species like Fragilariopsis reginae-jahniae. The Melville Bay core spans the last 8000 years, the North Water Polynya core spans the last 4000 years, and the Placentia Bay core spans the last 5800 years, providing a broad account of Archaeomonas spp. and diatom species abundances over the Holocene. It was concluded that Archaeomonas spp. was not directly correlated with known sea ice diatom species like F. reginae-jahniae at any of the three study sites. Archaeomonas spp. did display some similar relationships with cold water species like Thalassiosira hyalina, Thalassiothrix longissima, Thalassiosira nordenskioeldii and Fragilariopsis oceanica, and pack ice species like Actinocyclus curvatulus and Melosira arctica. Archaeomonas spp. can form in a range of conditions but prefers colder conditions where sea ice may form or drift to, as opposed to warmer, open water conditions. However, it is not directly linked to sea ice. Further research should focus on understanding whether Archaeomonas spp. forms in sea ice or not. There were some suggestions made to identifying Archaeomonas spp. at species level, but further research should be conducted on Archaeomonas spp.’s morphology to ... Master Thesis Arctic Climate change North Atlantic Sea ice Helsingfors Universitet: HELDA – Helsingin yliopiston digitaalinen arkisto Arctic |
institution |
Open Polar |
collection |
Helsingfors Universitet: HELDA – Helsingin yliopiston digitaalinen arkisto |
op_collection_id |
ftunivhelsihelda |
language |
English |
topic |
sea ice diatom chrysophyte cyst Holocene North Atlantic Archaeomonas spp Ympäristömuutoksen ja globaalin kestävyyden maisteriohjelma (ECGS) Master's Programme in Environmental Change and Global Sustainability Magisterprogrammet i miljöförändringar och global hållbarhet Ympäristömuutos Environmental Change Miljöförändring |
spellingShingle |
sea ice diatom chrysophyte cyst Holocene North Atlantic Archaeomonas spp Ympäristömuutoksen ja globaalin kestävyyden maisteriohjelma (ECGS) Master's Programme in Environmental Change and Global Sustainability Magisterprogrammet i miljöförändringar och global hållbarhet Ympäristömuutos Environmental Change Miljöförändring Anna, Leppänen Assessing the potential of the chrysophyte cyst Archaeomonas spp. as a sea ice proxy in the North Atlantic during the Holocene |
topic_facet |
sea ice diatom chrysophyte cyst Holocene North Atlantic Archaeomonas spp Ympäristömuutoksen ja globaalin kestävyyden maisteriohjelma (ECGS) Master's Programme in Environmental Change and Global Sustainability Magisterprogrammet i miljöförändringar och global hållbarhet Ympäristömuutos Environmental Change Miljöförändring |
description |
Climate change and temperature rise in the Arctic is resulting in a decrease in sea ice extent and changes in sea ice variability. The impact of climate change on sea ice variability can be better understood when studying past events of climate change and sea ice extent change. Past environmental change can be reconstructed using bioindicators such as chrysophyte cysts, siliceous resting stages of chrysophyte algae. Archaeomonas spp., a genus of chrysophyte cyst, is often found preserved in Marginal Ice Zone sediments in the Arctic and its relationship with sea ice extent is explored here, to further understand its potential as a sea ice proxy. Diatom slides from three cores in the North Atlantic (Melville Bay, the North Water Polynya and Placentia Bay) were used to evaluate relationships between Archaeomonas spp. and known sea ice diatom species like Fragilariopsis reginae-jahniae. The Melville Bay core spans the last 8000 years, the North Water Polynya core spans the last 4000 years, and the Placentia Bay core spans the last 5800 years, providing a broad account of Archaeomonas spp. and diatom species abundances over the Holocene. It was concluded that Archaeomonas spp. was not directly correlated with known sea ice diatom species like F. reginae-jahniae at any of the three study sites. Archaeomonas spp. did display some similar relationships with cold water species like Thalassiosira hyalina, Thalassiothrix longissima, Thalassiosira nordenskioeldii and Fragilariopsis oceanica, and pack ice species like Actinocyclus curvatulus and Melosira arctica. Archaeomonas spp. can form in a range of conditions but prefers colder conditions where sea ice may form or drift to, as opposed to warmer, open water conditions. However, it is not directly linked to sea ice. Further research should focus on understanding whether Archaeomonas spp. forms in sea ice or not. There were some suggestions made to identifying Archaeomonas spp. at species level, but further research should be conducted on Archaeomonas spp.’s morphology to ... |
author2 |
Helsingin yliopisto, Bio- ja ympäristötieteellinen tiedekunta University of Helsinki, Faculty of Biological and Environmental Sciences Helsingfors universitet, Bio- och miljövetenskapliga fakulteten |
format |
Master Thesis |
author |
Anna, Leppänen |
author_facet |
Anna, Leppänen |
author_sort |
Anna, Leppänen |
title |
Assessing the potential of the chrysophyte cyst Archaeomonas spp. as a sea ice proxy in the North Atlantic during the Holocene |
title_short |
Assessing the potential of the chrysophyte cyst Archaeomonas spp. as a sea ice proxy in the North Atlantic during the Holocene |
title_full |
Assessing the potential of the chrysophyte cyst Archaeomonas spp. as a sea ice proxy in the North Atlantic during the Holocene |
title_fullStr |
Assessing the potential of the chrysophyte cyst Archaeomonas spp. as a sea ice proxy in the North Atlantic during the Holocene |
title_full_unstemmed |
Assessing the potential of the chrysophyte cyst Archaeomonas spp. as a sea ice proxy in the North Atlantic during the Holocene |
title_sort |
assessing the potential of the chrysophyte cyst archaeomonas spp. as a sea ice proxy in the north atlantic during the holocene |
publisher |
Helsingin yliopisto |
publishDate |
2023 |
url |
http://hdl.handle.net/10138/358752 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Climate change North Atlantic Sea ice |
genre_facet |
Arctic Climate change North Atlantic Sea ice |
op_relation |
URN:NBN:fi:hulib-202306132588 http://hdl.handle.net/10138/358752 |
_version_ |
1774714901205352448 |