Landscape history and contemporary environmental drivers of microbial community structure and function
Recent work in microbial ecology has focused on elucidating controls over biogeographic patterns and connecting microbial community composition to ecosystem function. My objective was to investigate the relative influences of landscape legacies and contemporary environmental factors on the distribut...
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ftvirginiatec:oai:vtechworks.lib.vt.edu:10919/31883 2024-05-19T07:30:05+00:00 Landscape history and contemporary environmental drivers of microbial community structure and function Altrichter, Adam E. Biology Barrett, John E. Webster, Jackson R. Wynne, Randolph H. Gooseff, Michael N. 2010-04-10 application/pdf http://hdl.handle.net/10919/31883 http://scholar.lib.vt.edu/theses/available/etd-04242012-143200/ unknown Virginia Tech Altrichter_AE_T_2012.pdf etd-04242012-143200 http://hdl.handle.net/10919/31883 http://scholar.lib.vt.edu/theses/available/etd-04242012-143200/ In Copyright http://rightsstatements.org/vocab/InC/1.0/ extracellular enzyme activity McMurdo Dry Valleys microbial biogeography T-RFLP community similarity soil geochemistry Thesis 2010 ftvirginiatec 2024-05-01T01:13:13Z Recent work in microbial ecology has focused on elucidating controls over biogeographic patterns and connecting microbial community composition to ecosystem function. My objective was to investigate the relative influences of landscape legacies and contemporary environmental factors on the distribution of soil microbial communities and their contribution to ecosystem processes across a glacial till sequence in Taylor Valley, Antarctica. Within each till unit, I sampled from dry areas and areas with visible evidence of recent surface water movement generated by seasonal melting of ephemeral snow packs and hillslope ground ice. Using T-RFLP 16S rRNA gene profiles of microbial communities, I analyzed the contribution of till and environmental factors to community similarity, and assessed the functional potential of the microbial community using extracellular enzyme activity assays. Microbial communities were influenced by geochemical differences among both tills and local environments, but especially organized by variables associated with water availability as the first axis of an NMDS ordination was strongly related to shifts in soil moisture content. CCA revealed that tills explained only 3.4% of the variability in community similarity among sites, while geochemical variables explained 18.5%. Extracellular enzyme activity was correlated with relevant geochemical variables reflecting the influence of nutrient limitation on microbial activity. In addition, enzyme activity was related to changes in community similarity, particularly in wet environments with a partial Mantel correlation of 0.32. These results demonstrate how landscape history and environmental conditions can shape the functional potential of a microbial community mediated through shifts in microbial community composition. Master of Science Thesis Antarc* Antarctica McMurdo Dry Valleys VTechWorks (VirginiaTech) |
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VTechWorks (VirginiaTech) |
op_collection_id |
ftvirginiatec |
language |
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topic |
extracellular enzyme activity McMurdo Dry Valleys microbial biogeography T-RFLP community similarity soil geochemistry |
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extracellular enzyme activity McMurdo Dry Valleys microbial biogeography T-RFLP community similarity soil geochemistry Altrichter, Adam E. Landscape history and contemporary environmental drivers of microbial community structure and function |
topic_facet |
extracellular enzyme activity McMurdo Dry Valleys microbial biogeography T-RFLP community similarity soil geochemistry |
description |
Recent work in microbial ecology has focused on elucidating controls over biogeographic patterns and connecting microbial community composition to ecosystem function. My objective was to investigate the relative influences of landscape legacies and contemporary environmental factors on the distribution of soil microbial communities and their contribution to ecosystem processes across a glacial till sequence in Taylor Valley, Antarctica. Within each till unit, I sampled from dry areas and areas with visible evidence of recent surface water movement generated by seasonal melting of ephemeral snow packs and hillslope ground ice. Using T-RFLP 16S rRNA gene profiles of microbial communities, I analyzed the contribution of till and environmental factors to community similarity, and assessed the functional potential of the microbial community using extracellular enzyme activity assays. Microbial communities were influenced by geochemical differences among both tills and local environments, but especially organized by variables associated with water availability as the first axis of an NMDS ordination was strongly related to shifts in soil moisture content. CCA revealed that tills explained only 3.4% of the variability in community similarity among sites, while geochemical variables explained 18.5%. Extracellular enzyme activity was correlated with relevant geochemical variables reflecting the influence of nutrient limitation on microbial activity. In addition, enzyme activity was related to changes in community similarity, particularly in wet environments with a partial Mantel correlation of 0.32. These results demonstrate how landscape history and environmental conditions can shape the functional potential of a microbial community mediated through shifts in microbial community composition. Master of Science |
author2 |
Biology Barrett, John E. Webster, Jackson R. Wynne, Randolph H. Gooseff, Michael N. |
format |
Thesis |
author |
Altrichter, Adam E. |
author_facet |
Altrichter, Adam E. |
author_sort |
Altrichter, Adam E. |
title |
Landscape history and contemporary environmental drivers of microbial community structure and function |
title_short |
Landscape history and contemporary environmental drivers of microbial community structure and function |
title_full |
Landscape history and contemporary environmental drivers of microbial community structure and function |
title_fullStr |
Landscape history and contemporary environmental drivers of microbial community structure and function |
title_full_unstemmed |
Landscape history and contemporary environmental drivers of microbial community structure and function |
title_sort |
landscape history and contemporary environmental drivers of microbial community structure and function |
publisher |
Virginia Tech |
publishDate |
2010 |
url |
http://hdl.handle.net/10919/31883 http://scholar.lib.vt.edu/theses/available/etd-04242012-143200/ |
genre |
Antarc* Antarctica McMurdo Dry Valleys |
genre_facet |
Antarc* Antarctica McMurdo Dry Valleys |
op_relation |
Altrichter_AE_T_2012.pdf etd-04242012-143200 http://hdl.handle.net/10919/31883 http://scholar.lib.vt.edu/theses/available/etd-04242012-143200/ |
op_rights |
In Copyright http://rightsstatements.org/vocab/InC/1.0/ |
_version_ |
1799483606701178880 |