Environmental filtering of bacteria in low productivity habitats
Microbes fulfill important ecosystem functions by contributing as drivers of global nutrient cycles. Their distribution patterns are mainly controlled by environmental heterogeneities. So far, little is known about the mode of action of particular environmental drivers on the microbiota, particularl...
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Uppsala universitet, Limnologi
2014
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ftuppsalauniv:oai:DiVA.org:uu-229144 2023-05-15T18:25:11+02:00 Environmental filtering of bacteria in low productivity habitats Richert, Inga 2014 application/pdf http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-229144 eng eng Uppsala universitet, Limnologi Department of Environmental Microbiology, Helmholtz Centre for Environmental Research – UFZ, Microbial Ecosystem Services Group, Leipzig, Germany Uppsala Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, 1651-6214 1157 http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-229144 urn:isbn:978-91-554-8986-1 info:eu-repo/semantics/openAccess bacteria environmental filtering diversity ecosystem service hydrocarbon utilization Southern Ocean sediment Doctoral thesis, comprehensive summary info:eu-repo/semantics/doctoralThesis text 2014 ftuppsalauniv 2023-02-23T21:40:12Z Microbes fulfill important ecosystem functions by contributing as drivers of global nutrient cycles. Their distribution patterns are mainly controlled by environmental heterogeneities. So far, little is known about the mode of action of particular environmental drivers on the microbiota, particularly in low productivity habitats. The aim of this thesis was to investigate the relationships between local environmental drivers and the microbial responses at the level of communities, individuals and realized function, using three structurally different model habitats sharing the feature of overall low productivity. Using a hypothesis-based approach and extensive 16S rRNA amplicon mapping of bacterioplankton colonizing the polar Southern Ocean, I identified how the seasonal formation of open-water polynyas and coupled phytoplankton production affected the diversity of surface bacterial communities and resulted in a cascading effect influencing the underlying dark polar water masses. Additional laboratory experiments, with cultures exposed to light, resulted in reduction in alpha diversity and promoted opportunistic populations with most bacterial populations thriving in the cultures typically reflected the dominants in situ. Furthermore it was experimentally tested how induced cyclic water table fluctuations shaping environmental heterogeneity in a constructed wetland on temporal scale, by directly affecting redox conditions. Twelve months of water table fluctuations resulted in enhanced microbial biomass, however a shift in community composition did not lead to a significant increase in pollutant removal efficiency when compared to a static control wetland. I detected phyla that have previously been proposed as key players in anaerobic benzene break-down using a protocol that was developed for single cell activity screening using isotope-substrate uptake and microautoradiography combined with taxonomic identification based on fluorescent in situ hybridization targeting the 16S rRNA. Eventually, I provide an example ... Doctoral or Postdoctoral Thesis Southern Ocean Uppsala University: Publications (DiVA) Southern Ocean |
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Uppsala University: Publications (DiVA) |
op_collection_id |
ftuppsalauniv |
language |
English |
topic |
bacteria environmental filtering diversity ecosystem service hydrocarbon utilization Southern Ocean sediment |
spellingShingle |
bacteria environmental filtering diversity ecosystem service hydrocarbon utilization Southern Ocean sediment Richert, Inga Environmental filtering of bacteria in low productivity habitats |
topic_facet |
bacteria environmental filtering diversity ecosystem service hydrocarbon utilization Southern Ocean sediment |
description |
Microbes fulfill important ecosystem functions by contributing as drivers of global nutrient cycles. Their distribution patterns are mainly controlled by environmental heterogeneities. So far, little is known about the mode of action of particular environmental drivers on the microbiota, particularly in low productivity habitats. The aim of this thesis was to investigate the relationships between local environmental drivers and the microbial responses at the level of communities, individuals and realized function, using three structurally different model habitats sharing the feature of overall low productivity. Using a hypothesis-based approach and extensive 16S rRNA amplicon mapping of bacterioplankton colonizing the polar Southern Ocean, I identified how the seasonal formation of open-water polynyas and coupled phytoplankton production affected the diversity of surface bacterial communities and resulted in a cascading effect influencing the underlying dark polar water masses. Additional laboratory experiments, with cultures exposed to light, resulted in reduction in alpha diversity and promoted opportunistic populations with most bacterial populations thriving in the cultures typically reflected the dominants in situ. Furthermore it was experimentally tested how induced cyclic water table fluctuations shaping environmental heterogeneity in a constructed wetland on temporal scale, by directly affecting redox conditions. Twelve months of water table fluctuations resulted in enhanced microbial biomass, however a shift in community composition did not lead to a significant increase in pollutant removal efficiency when compared to a static control wetland. I detected phyla that have previously been proposed as key players in anaerobic benzene break-down using a protocol that was developed for single cell activity screening using isotope-substrate uptake and microautoradiography combined with taxonomic identification based on fluorescent in situ hybridization targeting the 16S rRNA. Eventually, I provide an example ... |
format |
Doctoral or Postdoctoral Thesis |
author |
Richert, Inga |
author_facet |
Richert, Inga |
author_sort |
Richert, Inga |
title |
Environmental filtering of bacteria in low productivity habitats |
title_short |
Environmental filtering of bacteria in low productivity habitats |
title_full |
Environmental filtering of bacteria in low productivity habitats |
title_fullStr |
Environmental filtering of bacteria in low productivity habitats |
title_full_unstemmed |
Environmental filtering of bacteria in low productivity habitats |
title_sort |
environmental filtering of bacteria in low productivity habitats |
publisher |
Uppsala universitet, Limnologi |
publishDate |
2014 |
url |
http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-229144 |
geographic |
Southern Ocean |
geographic_facet |
Southern Ocean |
genre |
Southern Ocean |
genre_facet |
Southern Ocean |
op_relation |
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, 1651-6214 1157 http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-229144 urn:isbn:978-91-554-8986-1 |
op_rights |
info:eu-repo/semantics/openAccess |
_version_ |
1766206450075435008 |