Microbial communities of Antarctic soil and lithic habitats
Global climate change is predicted to significantly alter extreme terrestrial environments. The disturbance of desert ecosystems is predicted to profoundly alter key biological processes that are thought to be mediated by micro-organisms in these delicate biomes. The Antarctic Dry Valleys are a seri...
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ftunivpretoria:oai:repository.up.ac.za:2263/45915 2023-05-15T13:48:21+02:00 Microbial communities of Antarctic soil and lithic habitats Van Goethem, Marc W. Cowan, Don A. Makhalanyane, Thulani P. 2015/04/22 http://hdl.handle.net/2263/45915 en eng University of Pretoria http://hdl.handle.net/2263/45915 Van Goethem, MW 2015, Microbial communities of Antarctic soil and lithic habitats, MSc Dissertation, University of Pretoria, Pretoria, viewed yymmdd <http://hdl.handle.net/2263/45915> A2015 © 2015 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. UCTD Dissertation 2015 ftunivpretoria 2022-05-31T13:32:47Z Global climate change is predicted to significantly alter extreme terrestrial environments. The disturbance of desert ecosystems is predicted to profoundly alter key biological processes that are thought to be mediated by micro-organisms in these delicate biomes. The Antarctic Dry Valleys are a series of hyperarid polar deserts which are highly oligotrophic, experience near-constant below-freezing temperatures, and are critically low in bioavailable moisture. However, increases in surface temperatures and ultra-violet irradiation are predicted to supply endemic microbial communities with previously unattainable levels of moisture and nutrients as ice melt intensifies. Understanding the responses of local microbial populations to changes in moisture content is the critical focus of this study. Here microbial fingerprinting and pyrosequencing in combination with multivariate statistical analyses were utilised to address this knowledge deficit. This study presents evidence supporting the concept of ecological niche partitioning between local desert habitats (Pointing et al., 2009). Multivariate analysis of bacterial 16S rRNA gene-defined communities generated using T-RFLP showed that edaphic niches; hypoliths, endoliths, soils and mat communities, were distinct in structure. However, local Cyanobacterial populations were not delineated by habitat. Pyrosequencing data revealed that soil communities were highly diverse and are predicted to ‘seed’ development of specialised communities, such as hypoliths and endoliths, which supports the concept of species recruitment from soils in desert systems (Makhalanyane et al., 2013b). The role of moisture content was less significant in determining local bacterial diversity patterns according to the fingerprinting techniques applied here. However, pyrosequencing data suggested that Cyanobacterial abundance and diversity was greater in communities exposed to higher levels of moisture content. These data suggest that increases in local moisture content may influence ... Doctoral or Postdoctoral Thesis Antarc* Antarctic University of Pretoria: UPSpace Antarctic The Antarctic |
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University of Pretoria: UPSpace |
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ftunivpretoria |
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English |
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UCTD |
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UCTD Van Goethem, Marc W. Microbial communities of Antarctic soil and lithic habitats |
topic_facet |
UCTD |
description |
Global climate change is predicted to significantly alter extreme terrestrial environments. The disturbance of desert ecosystems is predicted to profoundly alter key biological processes that are thought to be mediated by micro-organisms in these delicate biomes. The Antarctic Dry Valleys are a series of hyperarid polar deserts which are highly oligotrophic, experience near-constant below-freezing temperatures, and are critically low in bioavailable moisture. However, increases in surface temperatures and ultra-violet irradiation are predicted to supply endemic microbial communities with previously unattainable levels of moisture and nutrients as ice melt intensifies. Understanding the responses of local microbial populations to changes in moisture content is the critical focus of this study. Here microbial fingerprinting and pyrosequencing in combination with multivariate statistical analyses were utilised to address this knowledge deficit. This study presents evidence supporting the concept of ecological niche partitioning between local desert habitats (Pointing et al., 2009). Multivariate analysis of bacterial 16S rRNA gene-defined communities generated using T-RFLP showed that edaphic niches; hypoliths, endoliths, soils and mat communities, were distinct in structure. However, local Cyanobacterial populations were not delineated by habitat. Pyrosequencing data revealed that soil communities were highly diverse and are predicted to ‘seed’ development of specialised communities, such as hypoliths and endoliths, which supports the concept of species recruitment from soils in desert systems (Makhalanyane et al., 2013b). The role of moisture content was less significant in determining local bacterial diversity patterns according to the fingerprinting techniques applied here. However, pyrosequencing data suggested that Cyanobacterial abundance and diversity was greater in communities exposed to higher levels of moisture content. These data suggest that increases in local moisture content may influence ... |
author2 |
Cowan, Don A. Makhalanyane, Thulani P. |
format |
Doctoral or Postdoctoral Thesis |
author |
Van Goethem, Marc W. |
author_facet |
Van Goethem, Marc W. |
author_sort |
Van Goethem, Marc W. |
title |
Microbial communities of Antarctic soil and lithic habitats |
title_short |
Microbial communities of Antarctic soil and lithic habitats |
title_full |
Microbial communities of Antarctic soil and lithic habitats |
title_fullStr |
Microbial communities of Antarctic soil and lithic habitats |
title_full_unstemmed |
Microbial communities of Antarctic soil and lithic habitats |
title_sort |
microbial communities of antarctic soil and lithic habitats |
publisher |
University of Pretoria |
publishDate |
2015 |
url |
http://hdl.handle.net/2263/45915 |
geographic |
Antarctic The Antarctic |
geographic_facet |
Antarctic The Antarctic |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_relation |
http://hdl.handle.net/2263/45915 Van Goethem, MW 2015, Microbial communities of Antarctic soil and lithic habitats, MSc Dissertation, University of Pretoria, Pretoria, viewed yymmdd <http://hdl.handle.net/2263/45915> A2015 |
op_rights |
© 2015 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. |
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