Quantifying Long-Term Geomorphology of Antarctic Streams
In 1994, 16 stream transects were established in the McMurdo Dry Valleys of Antarctica beginning a long term data set characterizing microbial communities and channel geometry. The transects were established to record microbial mat dynamics and stream geomorphology. To accomplish this, the transects...
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ftunicolboulder:oai:scholar.colorado.edu:cven_gradetds-1188 2023-05-15T13:49:40+02:00 Quantifying Long-Term Geomorphology of Antarctic Streams Crisp, Steven William 2015-01-01T08:00:00Z application/pdf https://scholar.colorado.edu/cven_gradetds/182 https://scholar.colorado.edu/cgi/viewcontent.cgi?article=1188&context=cven_gradetds unknown CU Scholar https://scholar.colorado.edu/cven_gradetds/182 https://scholar.colorado.edu/cgi/viewcontent.cgi?article=1188&context=cven_gradetds Civil Engineering Graduate Theses & Dissertations algae geomorphology lidar McMurdo streams survey Civil Engineering Environmental Microbiology and Microbial Ecology text 2015 ftunicolboulder 2018-10-07T09:08:02Z In 1994, 16 stream transects were established in the McMurdo Dry Valleys of Antarctica beginning a long term data set characterizing microbial communities and channel geometry. The transects were established to record microbial mat dynamics and stream geomorphology. To accomplish this, the transects were surveyed for points of interest outside and inside the stream channel. Beginning in 2010 the microbial surveys received ground based LiDAR support. This allowed for greater resolution in mapping and analyzing stream morphology than traditional surveying methods. The purpose of this study was to overlap the traditional methods of surveying individual points of interest with a data cloud representing the entire stream transect to be able to continue the microbial study into the future unabated. Using surveyed microbial mats as an indicator of a location in time, a history of channel elevations was created for 7 transects. In general, the streams have not changed significantly in the 20 year record, with exceptions being the steep channel of Bohner Stream, and Huey Creek, which receives large sediment loads from the sharply incised upstream channel, both of which saw large variations in maximum bed change exceeding 75cm and 150 cm respectively. In addition to creating an elevation history, relative bed change was plotted against the ash free dry mass of the microbial mats sampled to determine the resilience of the mats. It was found that microbial mats are more abundant in areas of near zero change. The four microbial mats studied however, which include green, black, orange, and red mats, differed greatly in adaptability with regards to bed change. Green microbial mats, which are typically hidden under large immobile rocks, were not often found in areas with any significant bed change. Conversely, orange mats were found in the most dynamic parts of the stream bed with outliers seen in areas with change exceeding 50 cm with. Finally black microbial mats had the largest values of ash free dry mass indicating the largest resilience to the scouring effects of high flow. Text Antarc* Antarctic Antarctica McMurdo Dry Valleys University of Colorado, Boulder: CU Scholar Antarctic McMurdo Dry Valleys Huey Creek ENVELOPE(163.100,163.100,-77.600,-77.600) Bohner Stream ENVELOPE(162.533,162.533,-77.700,-77.700) |
institution |
Open Polar |
collection |
University of Colorado, Boulder: CU Scholar |
op_collection_id |
ftunicolboulder |
language |
unknown |
topic |
algae geomorphology lidar McMurdo streams survey Civil Engineering Environmental Microbiology and Microbial Ecology |
spellingShingle |
algae geomorphology lidar McMurdo streams survey Civil Engineering Environmental Microbiology and Microbial Ecology Crisp, Steven William Quantifying Long-Term Geomorphology of Antarctic Streams |
topic_facet |
algae geomorphology lidar McMurdo streams survey Civil Engineering Environmental Microbiology and Microbial Ecology |
description |
In 1994, 16 stream transects were established in the McMurdo Dry Valleys of Antarctica beginning a long term data set characterizing microbial communities and channel geometry. The transects were established to record microbial mat dynamics and stream geomorphology. To accomplish this, the transects were surveyed for points of interest outside and inside the stream channel. Beginning in 2010 the microbial surveys received ground based LiDAR support. This allowed for greater resolution in mapping and analyzing stream morphology than traditional surveying methods. The purpose of this study was to overlap the traditional methods of surveying individual points of interest with a data cloud representing the entire stream transect to be able to continue the microbial study into the future unabated. Using surveyed microbial mats as an indicator of a location in time, a history of channel elevations was created for 7 transects. In general, the streams have not changed significantly in the 20 year record, with exceptions being the steep channel of Bohner Stream, and Huey Creek, which receives large sediment loads from the sharply incised upstream channel, both of which saw large variations in maximum bed change exceeding 75cm and 150 cm respectively. In addition to creating an elevation history, relative bed change was plotted against the ash free dry mass of the microbial mats sampled to determine the resilience of the mats. It was found that microbial mats are more abundant in areas of near zero change. The four microbial mats studied however, which include green, black, orange, and red mats, differed greatly in adaptability with regards to bed change. Green microbial mats, which are typically hidden under large immobile rocks, were not often found in areas with any significant bed change. Conversely, orange mats were found in the most dynamic parts of the stream bed with outliers seen in areas with change exceeding 50 cm with. Finally black microbial mats had the largest values of ash free dry mass indicating the largest resilience to the scouring effects of high flow. |
format |
Text |
author |
Crisp, Steven William |
author_facet |
Crisp, Steven William |
author_sort |
Crisp, Steven William |
title |
Quantifying Long-Term Geomorphology of Antarctic Streams |
title_short |
Quantifying Long-Term Geomorphology of Antarctic Streams |
title_full |
Quantifying Long-Term Geomorphology of Antarctic Streams |
title_fullStr |
Quantifying Long-Term Geomorphology of Antarctic Streams |
title_full_unstemmed |
Quantifying Long-Term Geomorphology of Antarctic Streams |
title_sort |
quantifying long-term geomorphology of antarctic streams |
publisher |
CU Scholar |
publishDate |
2015 |
url |
https://scholar.colorado.edu/cven_gradetds/182 https://scholar.colorado.edu/cgi/viewcontent.cgi?article=1188&context=cven_gradetds |
long_lat |
ENVELOPE(163.100,163.100,-77.600,-77.600) ENVELOPE(162.533,162.533,-77.700,-77.700) |
geographic |
Antarctic McMurdo Dry Valleys Huey Creek Bohner Stream |
geographic_facet |
Antarctic McMurdo Dry Valleys Huey Creek Bohner Stream |
genre |
Antarc* Antarctic Antarctica McMurdo Dry Valleys |
genre_facet |
Antarc* Antarctic Antarctica McMurdo Dry Valleys |
op_source |
Civil Engineering Graduate Theses & Dissertations |
op_relation |
https://scholar.colorado.edu/cven_gradetds/182 https://scholar.colorado.edu/cgi/viewcontent.cgi?article=1188&context=cven_gradetds |
_version_ |
1766251938346696704 |