Biogeochemistry and hydrology of three alpine proglacial environments resulting from glacier retreat
Proglacial environments, formed by glacier retreat, exhibit distinct characteristics in discharge, water temperature, water residence time, and dissolved ion, carbon, and suspended sediment concentrations. The unnamed alpine glacier at the headwaters of the Wheaton River, Yukon, Canada, provides an...
Main Author: | |
---|---|
Other Authors: | |
Format: | Thesis |
Language: | English |
Published: |
Montana State University - Bozeman, College of Letters & Science
2008
|
Subjects: | |
Online Access: | https://scholarworks.montana.edu/xmlui/handle/1/994 |
id |
ftmontanastateu:oai:scholarworks.montana.edu:1/994 |
---|---|
record_format |
openpolar |
spelling |
ftmontanastateu:oai:scholarworks.montana.edu:1/994 2023-05-15T16:22:30+02:00 Biogeochemistry and hydrology of three alpine proglacial environments resulting from glacier retreat Bruckner, Monica Zanzola Chairperson, Graduate Committee: Mark L. Skidmore North America 2008 application/pdf https://scholarworks.montana.edu/xmlui/handle/1/994 en eng Montana State University - Bozeman, College of Letters & Science https://scholarworks.montana.edu/xmlui/handle/1/994 Copyright 2008 by Monica Zanzola Bruckner Hydrology Mountain plants Mountain ecology Carbon cycle (Biogeochemistry) Glacial epoch Thesis 2008 ftmontanastateu 2022-06-06T07:28:36Z Proglacial environments, formed by glacier retreat, exhibit distinct characteristics in discharge, water temperature, water residence time, and dissolved ion, carbon, and suspended sediment concentrations. The unnamed alpine glacier at the headwaters of the Wheaton River, Yukon, Canada, provides an ideal setting to compare deglaciation processes that result in three different proglacial environments. The glacier has evolved from occupying one large catchment (~4 km²) to two smaller catchments (each ~2 km²) via glacier thinning and net mass loss, forming two lobes separated by a medial moraine. Field observations revealed neither crevasses nor evidence of subglacial drainage outlets and suggested this glacier had a non-temperate thermal regime with meltwater predominantly flowing from supraglacial and ice marginal sources. Climate and bedrock geology were similar for the subcatchments, providing a natural laboratory to compare deglaciation processes. This study compared the hydrology and biogeochemistry of three outlet streams from this glacier: one stream drained a proglacial lake which is fed by meltwater from the lower west lobe, a second stream drained the upper west lobe, and a third stream was the major drainage outlet for the east lobe. Hydrologic monitoring over the 2006 melt season (June-August) and analyses of water samples for dissolved ion content and carbon indicated that the meltwaters are dominated by Ca²+ and HCO 3-, which are derived from biogeochemical weathering of crustal materials. The study demonstrated that the presence of the proglacial lake, which acted as a meltwater reservoir, measurably modified meltwater residence time, water temperature, water chemistry, and bacterial biomass relative to the proglacial streams. Rock:water interaction between meltwater and medial morainal sediment and fine-grained, reactive glacial flour suspended in the streams and the lake water column also enhanced biogeochemical weathering within the catchment. Thus, this study provided a small-scale example for ... Thesis glacier* Yukon Montana State University (MSU): ScholarWorks Canada Wheaton River ENVELOPE(-134.886,-134.886,60.109,60.109) Yukon |
institution |
Open Polar |
collection |
Montana State University (MSU): ScholarWorks |
op_collection_id |
ftmontanastateu |
language |
English |
topic |
Hydrology Mountain plants Mountain ecology Carbon cycle (Biogeochemistry) Glacial epoch |
spellingShingle |
Hydrology Mountain plants Mountain ecology Carbon cycle (Biogeochemistry) Glacial epoch Bruckner, Monica Zanzola Biogeochemistry and hydrology of three alpine proglacial environments resulting from glacier retreat |
topic_facet |
Hydrology Mountain plants Mountain ecology Carbon cycle (Biogeochemistry) Glacial epoch |
description |
Proglacial environments, formed by glacier retreat, exhibit distinct characteristics in discharge, water temperature, water residence time, and dissolved ion, carbon, and suspended sediment concentrations. The unnamed alpine glacier at the headwaters of the Wheaton River, Yukon, Canada, provides an ideal setting to compare deglaciation processes that result in three different proglacial environments. The glacier has evolved from occupying one large catchment (~4 km²) to two smaller catchments (each ~2 km²) via glacier thinning and net mass loss, forming two lobes separated by a medial moraine. Field observations revealed neither crevasses nor evidence of subglacial drainage outlets and suggested this glacier had a non-temperate thermal regime with meltwater predominantly flowing from supraglacial and ice marginal sources. Climate and bedrock geology were similar for the subcatchments, providing a natural laboratory to compare deglaciation processes. This study compared the hydrology and biogeochemistry of three outlet streams from this glacier: one stream drained a proglacial lake which is fed by meltwater from the lower west lobe, a second stream drained the upper west lobe, and a third stream was the major drainage outlet for the east lobe. Hydrologic monitoring over the 2006 melt season (June-August) and analyses of water samples for dissolved ion content and carbon indicated that the meltwaters are dominated by Ca²+ and HCO 3-, which are derived from biogeochemical weathering of crustal materials. The study demonstrated that the presence of the proglacial lake, which acted as a meltwater reservoir, measurably modified meltwater residence time, water temperature, water chemistry, and bacterial biomass relative to the proglacial streams. Rock:water interaction between meltwater and medial morainal sediment and fine-grained, reactive glacial flour suspended in the streams and the lake water column also enhanced biogeochemical weathering within the catchment. Thus, this study provided a small-scale example for ... |
author2 |
Chairperson, Graduate Committee: Mark L. Skidmore |
format |
Thesis |
author |
Bruckner, Monica Zanzola |
author_facet |
Bruckner, Monica Zanzola |
author_sort |
Bruckner, Monica Zanzola |
title |
Biogeochemistry and hydrology of three alpine proglacial environments resulting from glacier retreat |
title_short |
Biogeochemistry and hydrology of three alpine proglacial environments resulting from glacier retreat |
title_full |
Biogeochemistry and hydrology of three alpine proglacial environments resulting from glacier retreat |
title_fullStr |
Biogeochemistry and hydrology of three alpine proglacial environments resulting from glacier retreat |
title_full_unstemmed |
Biogeochemistry and hydrology of three alpine proglacial environments resulting from glacier retreat |
title_sort |
biogeochemistry and hydrology of three alpine proglacial environments resulting from glacier retreat |
publisher |
Montana State University - Bozeman, College of Letters & Science |
publishDate |
2008 |
url |
https://scholarworks.montana.edu/xmlui/handle/1/994 |
op_coverage |
North America |
long_lat |
ENVELOPE(-134.886,-134.886,60.109,60.109) |
geographic |
Canada Wheaton River Yukon |
geographic_facet |
Canada Wheaton River Yukon |
genre |
glacier* Yukon |
genre_facet |
glacier* Yukon |
op_relation |
https://scholarworks.montana.edu/xmlui/handle/1/994 |
op_rights |
Copyright 2008 by Monica Zanzola Bruckner |
_version_ |
1766010479664168960 |