Marion Island bryophytes: evidence for functional types based on traits related to photosynthesis and desiccation tolerance

Thesis (MSc)--Stellenbosch University, 2016. ENGLISH ABSTRACT: There is currently a worldwide interest in grouping species on the basis of their functional characteristics into plant functional types (PFTs). This reduces the complexity of models that predict the effects of global change on vegetatio...

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Main Author: Tonkie, Jacqueline Nicole
Other Authors: Smith, Valdon R., Stellenbosch University. Faculty of Science. Dept. of Botany and Zoology.
Format: Thesis
Language:English
Published: Stellenbosch : Stellenbosch University 2016
Subjects:
Online Access:http://hdl.handle.net/10019.1/98851
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spelling ftunstellenbosch:oai:scholar.sun.ac.za:10019.1/98851 2023-11-12T04:20:50+01:00 Marion Island bryophytes: evidence for functional types based on traits related to photosynthesis and desiccation tolerance Tonkie, Jacqueline Nicole Smith, Valdon R. Stellenbosch University. Faculty of Science. Dept. of Botany and Zoology. 2016-03 174 pages : illustrations application/pdf http://hdl.handle.net/10019.1/98851 en_ZA eng Stellenbosch : Stellenbosch University http://hdl.handle.net/10019.1/98851 Stellenbosch University Marion Island -- Plant functional types Marion Island vegetation Marion Island bryophyte species UCTD Thesis 2016 ftunstellenbosch 2023-10-22T07:17:45Z Thesis (MSc)--Stellenbosch University, 2016. ENGLISH ABSTRACT: There is currently a worldwide interest in grouping species on the basis of their functional characteristics into plant functional types (PFTs). This reduces the complexity of models that predict the effects of global change on vegetation and ecosystem processes. Marion Island has vegetation dominated by bryophytes and is experiencing intense climate change. However, there is no accepted scheme and no consensus on the most useful traits for a bryophyte PFT classification. This study aimed at grouping 38 of the island bryophyte species into functional groups. A suite of 14 photosynthetic traits related to light or desiccation response were obtained from chlorophyll fluorescence quenching analysis and water relations. The characteristics were subjected to analysis of variance, box plot rankings, principal component and clustering analyses to group the species into functional types. Seven light response groups and nine desiccation response groups were recognized. Six groups were recognized in the combined analysis of light and desiccation traits. The species with the highest photosynthetic capacity and lowest photoinhibition had low or moderate saturated moisture content, dried out slowly, low or moderate photoprotection capability in high light and when desiccated and moderate recovery of photochemistry upon rehydration. The species with the lowest photosynthetic capacity and highest photoinhibition had the highest saturated moisture content, dried out very fast, had low photoprotective capability in high light and when desiccated and showed very low to moderate recovery. The group of species with low photosynthetic capacity was distinguished from the group with the lowest photosynthetic capacity by having a higher quantum yield of electron transport at the optimal photosynthetically active radiation (PAR). The two groups consisting of moderate or high photosynthetic capacity species were distinguished by the fraction of open reaction centres in high ... Thesis Marion Island Stellenbosch University: SUNScholar Research Repository
institution Open Polar
collection Stellenbosch University: SUNScholar Research Repository
op_collection_id ftunstellenbosch
language English
topic Marion Island -- Plant functional types
Marion Island vegetation
Marion Island bryophyte species
UCTD
spellingShingle Marion Island -- Plant functional types
Marion Island vegetation
Marion Island bryophyte species
UCTD
Tonkie, Jacqueline Nicole
Marion Island bryophytes: evidence for functional types based on traits related to photosynthesis and desiccation tolerance
topic_facet Marion Island -- Plant functional types
Marion Island vegetation
Marion Island bryophyte species
UCTD
description Thesis (MSc)--Stellenbosch University, 2016. ENGLISH ABSTRACT: There is currently a worldwide interest in grouping species on the basis of their functional characteristics into plant functional types (PFTs). This reduces the complexity of models that predict the effects of global change on vegetation and ecosystem processes. Marion Island has vegetation dominated by bryophytes and is experiencing intense climate change. However, there is no accepted scheme and no consensus on the most useful traits for a bryophyte PFT classification. This study aimed at grouping 38 of the island bryophyte species into functional groups. A suite of 14 photosynthetic traits related to light or desiccation response were obtained from chlorophyll fluorescence quenching analysis and water relations. The characteristics were subjected to analysis of variance, box plot rankings, principal component and clustering analyses to group the species into functional types. Seven light response groups and nine desiccation response groups were recognized. Six groups were recognized in the combined analysis of light and desiccation traits. The species with the highest photosynthetic capacity and lowest photoinhibition had low or moderate saturated moisture content, dried out slowly, low or moderate photoprotection capability in high light and when desiccated and moderate recovery of photochemistry upon rehydration. The species with the lowest photosynthetic capacity and highest photoinhibition had the highest saturated moisture content, dried out very fast, had low photoprotective capability in high light and when desiccated and showed very low to moderate recovery. The group of species with low photosynthetic capacity was distinguished from the group with the lowest photosynthetic capacity by having a higher quantum yield of electron transport at the optimal photosynthetically active radiation (PAR). The two groups consisting of moderate or high photosynthetic capacity species were distinguished by the fraction of open reaction centres in high ...
author2 Smith, Valdon R.
Stellenbosch University. Faculty of Science. Dept. of Botany and Zoology.
format Thesis
author Tonkie, Jacqueline Nicole
author_facet Tonkie, Jacqueline Nicole
author_sort Tonkie, Jacqueline Nicole
title Marion Island bryophytes: evidence for functional types based on traits related to photosynthesis and desiccation tolerance
title_short Marion Island bryophytes: evidence for functional types based on traits related to photosynthesis and desiccation tolerance
title_full Marion Island bryophytes: evidence for functional types based on traits related to photosynthesis and desiccation tolerance
title_fullStr Marion Island bryophytes: evidence for functional types based on traits related to photosynthesis and desiccation tolerance
title_full_unstemmed Marion Island bryophytes: evidence for functional types based on traits related to photosynthesis and desiccation tolerance
title_sort marion island bryophytes: evidence for functional types based on traits related to photosynthesis and desiccation tolerance
publisher Stellenbosch : Stellenbosch University
publishDate 2016
url http://hdl.handle.net/10019.1/98851
genre Marion Island
genre_facet Marion Island
op_relation http://hdl.handle.net/10019.1/98851
op_rights Stellenbosch University
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