Full Text Available

Note: Clicking the button above will open the full text document at the original institutional repository in a new window.

Determinants of pattern in fynbos vegetation: physical site factors, disturbance regime, species attributes and temporal change

This study set out to explore the patterns and determinants of contemporary species distribution in a fynbos landscape based on information on 1) physical habitat characteristics, 2) past disturbance regime, 3) intrinsic properties of individual species and 4) temporal change in communities. The bod...

Full description

Saved in:
Bibliographic Details
Main Author: Privett, Sean David John
Other Authors: Cowling, Richard M
Format: Thesis
Language:English
Published: Department of Biological Sciences 2016
Subjects:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1867613330737201152
access_status_str Open Access
author Privett, Sean David John
author2 Cowling, Richard M
author_browse Cowling, Richard M
Privett, Sean David John
author_facet Cowling, Richard M
Privett, Sean David John
author_sort Privett, Sean David John
collection Thesis
description This study set out to explore the patterns and determinants of contemporary species distribution in a fynbos landscape based on information on 1) physical habitat characteristics, 2) past disturbance regime, 3) intrinsic properties of individual species and 4) temporal change in communities. The body of the thesis is divided into four parts covering each of these aspects individually. Each chapter has been written up as an individual paper and thus includes some repetition as well as cross-referencing. Each chapter includes a detailed rationale for the study in the introduction, as well as methods, results and a discussion of the findings. Chapter 2 describes the patterns of vegetation units in the Cape of Good Hope Nature Reserve and provides a quantitative assessment of the importance of physical site features as determinants of these units. These results are compared with the vegetation classifications of the area derived in earlier studies by Taylor (1984b) and Cowling et al. (1996a). Chapter 3 is the first study in fynbos to partition the variance in vegetation pattern into that explained by physical site factors and that explained by the recent disturbance regime. The study explores the role of 30 years of fire and alien plant infestations in influencing species distribution at the community and landscape scale. While a number of studies have explored spatial determinants of diversity and pattern in fynbos, temporal change within communities has been neglected. High levels of species turnover through time, as a result of colonisation and extinction, could be an important component of diversity at the landscape scale. Hence Chapters 4 and 5 both explore aspects of temporal dynamics in fynbos. The objectives of Chapter 4 are to determine the stability of populations at the landscape scale over a 30-year period and to establish the determinants of local extinction of species. Information on the stability of species over time and the attributes which enable species to persist or go extinct are important for understanding potential impacts of management practices as well as the importance of temporal dynamics in influencing spatial patterns. This is especially appropriate in the context of the results of Chapter 3, which suggest that a high proportion of the variance in species composition is unexplained despite the inclusion of physical factors, and past disturbance regime. The fifth chapter provides a descriptive account of the change in vegetation composition over a 30-year period. It is recommended that those readers not familiar with the fynbos system read it as it provides an overview of a variety of aspects of fynbos dynamics. Its objective is to show how the various components of the disturbance regime, as well as fluctuations in abundance of overstorey Proteaceae and their resultant competitive effects can influence community composition. The final chapter is a general discussion that summarises the major findings of the study.
format Thesis
id oai:open.uct.ac.za:11427/17365
institution University of Cape Town (South Africa)
language eng
last_indexed 2026-06-10T12:34:25.395Z
license_str Not specified — see source repository
provenance_str_mv Harvested via OAI-PMH from UCTD — University of Cape Town Open Access Repository
publishDate 2016
publishDateRange 2016
publishDateSort 2016
publisher Department of Biological Sciences
publisherStr Department of Biological Sciences
record_format dspace
source_str UCTD — University of Cape Town Open Access Repository
spelling oai:open.uct.ac.za:11427/17365 Determinants of pattern in fynbos vegetation: physical site factors, disturbance regime, species attributes and temporal change Privett, Sean David John Cowling, Richard M Botany Plant Ecology This study set out to explore the patterns and determinants of contemporary species distribution in a fynbos landscape based on information on 1) physical habitat characteristics, 2) past disturbance regime, 3) intrinsic properties of individual species and 4) temporal change in communities. The body of the thesis is divided into four parts covering each of these aspects individually. Each chapter has been written up as an individual paper and thus includes some repetition as well as cross-referencing. Each chapter includes a detailed rationale for the study in the introduction, as well as methods, results and a discussion of the findings. Chapter 2 describes the patterns of vegetation units in the Cape of Good Hope Nature Reserve and provides a quantitative assessment of the importance of physical site features as determinants of these units. These results are compared with the vegetation classifications of the area derived in earlier studies by Taylor (1984b) and Cowling et al. (1996a). Chapter 3 is the first study in fynbos to partition the variance in vegetation pattern into that explained by physical site factors and that explained by the recent disturbance regime. The study explores the role of 30 years of fire and alien plant infestations in influencing species distribution at the community and landscape scale. While a number of studies have explored spatial determinants of diversity and pattern in fynbos, temporal change within communities has been neglected. High levels of species turnover through time, as a result of colonisation and extinction, could be an important component of diversity at the landscape scale. Hence Chapters 4 and 5 both explore aspects of temporal dynamics in fynbos. The objectives of Chapter 4 are to determine the stability of populations at the landscape scale over a 30-year period and to establish the determinants of local extinction of species. Information on the stability of species over time and the attributes which enable species to persist or go extinct are important for understanding potential impacts of management practices as well as the importance of temporal dynamics in influencing spatial patterns. This is especially appropriate in the context of the results of Chapter 3, which suggest that a high proportion of the variance in species composition is unexplained despite the inclusion of physical factors, and past disturbance regime. The fifth chapter provides a descriptive account of the change in vegetation composition over a 30-year period. It is recommended that those readers not familiar with the fynbos system read it as it provides an overview of a variety of aspects of fynbos dynamics. Its objective is to show how the various components of the disturbance regime, as well as fluctuations in abundance of overstorey Proteaceae and their resultant competitive effects can influence community composition. The final chapter is a general discussion that summarises the major findings of the study. 2016-02-29T12:06:10Z 2016-02-29T12:06:10Z 1998 Master Thesis Masters MSc http://hdl.handle.net/11427/17365 eng application/pdf Department of Biological Sciences Faculty of Science University of Cape Town
spellingShingle Botany
Plant Ecology
Privett, Sean David John
Determinants of pattern in fynbos vegetation: physical site factors, disturbance regime, species attributes and temporal change
thesis_degree_str Master's
title Determinants of pattern in fynbos vegetation: physical site factors, disturbance regime, species attributes and temporal change
title_full Determinants of pattern in fynbos vegetation: physical site factors, disturbance regime, species attributes and temporal change
title_fullStr Determinants of pattern in fynbos vegetation: physical site factors, disturbance regime, species attributes and temporal change
title_full_unstemmed Determinants of pattern in fynbos vegetation: physical site factors, disturbance regime, species attributes and temporal change
title_short Determinants of pattern in fynbos vegetation: physical site factors, disturbance regime, species attributes and temporal change
title_sort determinants of pattern in fynbos vegetation physical site factors disturbance regime species attributes and temporal change
topic Botany
Plant Ecology
url http://hdl.handle.net/11427/17365
work_keys_str_mv AT privettseandavidjohn determinantsofpatterninfynbosvegetationphysicalsitefactorsdisturbanceregimespeciesattributesandtemporalchange