Full Text Available
Note: Clicking the button above will open the full text document at the original institutional repository in a new window.
Abundance and occupancy : use of a mesocosm to test pattern and process
Thesis (PhD (Entomology))--University of Pretoria, 2007.
Saved in:
| Other Authors: | |
|---|---|
| Format: | Thesis |
| Published: |
University of Pretoria
2013
|
| Subjects: | |
| Tags: |
No Tags, Be the first to tag this record!
|
| _version_ | 1867613565358178304 |
|---|---|
| access_status_str | Open Access |
| author2 | Nicolson, Sue W. |
| author_browse | Nicolson, Sue W. |
| author_facet | Nicolson, Sue W. |
| collection | Thesis |
| dc_rights_str_mv | © 2005 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. |
| description | Thesis (PhD (Entomology))--University of Pretoria, 2007. |
| format | Thesis |
| id | oai:repository.up.ac.za:2263/27789 |
| institution | University of Pretoria (South Africa) |
| last_indexed | 2026-06-10T12:38:09.710Z |
| license_str | Other — see source repository |
| provenance_str_mv | Harvested via OAI-PMH from UPSpace — University of Pretoria Institutional Repository |
| publishDate | 2013 |
| publishDateRange | 2013 |
| publishDateSort | 2013 |
| publisher | University of Pretoria |
| publisherStr | University of Pretoria |
| record_format | dspace |
| source_str | UPSpace — University of Pretoria Institutional Repository |
| spelling | oai:repository.up.ac.za:2263/27789 Abundance and occupancy : use of a mesocosm to test pattern and process Nicolson, Sue W. McGeogh, M.A. upetd@up.ac.za Chown, Steven Loudon Warren, Marie Mesocosm Drosophila simulans UCTD Thesis (PhD (Entomology))--University of Pretoria, 2007. Field-based mesocosm studies may be used as conceptual experiments to examine theoretical questions using the generated empirical data. A field-based Drosophilidae-nectarine mesocosm, comprising sun and shaded microclimate treatments arranged in a checkerboard design, was used in this thesis to examine four theoretical objectives. First, the efficacy of spatial analysis for detecting empirical pattern was examined. Natural variation weakened spatial structuring. However, hypothesis generation was shown not to be affected by this inclusion. Second, enhancing the hypothesis generating capacity of spatial methods was assessed, and confirmed to be possible, through the use of a sensitivity analysis method developed here. The method ( distinguished between mechanism categories (intrinsic, extrinsic and natural variation) and assessed the relative strength of each category. Next, an empirical test of the He and Gaston (2000a) parameterisation method and model to predict abundance from occupancy was conducted. Abundance estimates derived using the parameterisation method were underestimated because individuals were highly aggregated within fruit. This model and method require further exploration at fine scales for highly aggregated species. The incorporation of spatially explicit information may improve abundance predictions. Finally, the influence of spatial variation in temperature on adult body size in Drosophila simulans Sturtevant was investigated. The simple developmental effects of temperature differences, or the simple effects of stressful temperatures on thorax length, were overridden by interactive effects between temperature and larval density. As a result, flies attained the same final sizes in the shade and sun. Under natural conditions both mortality and non-lethal effects of temperature and/or crowding are likely to playa role in the evolution of body size. The results of this thesis provide i) an improved understanding of the influence of natural variation on spatial pattern, ii) an additional tool for spatial hypothesis generation, iii) an empirical test of an abundance-prediction model and iv) an understanding of interactive and non-lethal effects on body size under field conditions. The thesis therefore provides empirical support for the usefulness of field-based mesocosms to examine theoretical objectives. Zoology and Entomology unrestricted 2013-09-07T12:18:45Z 2006-09-19 2013-09-07T12:18:45Z 2006-05-02 2007-09-19 2006-09-06 Thesis Warren, M 2005, Abundance and occupancy : use of a mesocosm to test pattern and process, PhD thesis, University of Pretoria, Pretoria, viewed yymmdd < http://hdl.handle.net/2263/27789 > H842/ag http://hdl.handle.net/2263/27789 http://upetd.up.ac.za/thesis/available/etd-09062006-150712/ © 2005 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. application/pdf University of Pretoria |
| spellingShingle | Mesocosm Drosophila simulans UCTD Abundance and occupancy : use of a mesocosm to test pattern and process |
| title | Abundance and occupancy : use of a mesocosm to test pattern and process |
| title_full | Abundance and occupancy : use of a mesocosm to test pattern and process |
| title_fullStr | Abundance and occupancy : use of a mesocosm to test pattern and process |
| title_full_unstemmed | Abundance and occupancy : use of a mesocosm to test pattern and process |
| title_short | Abundance and occupancy : use of a mesocosm to test pattern and process |
| title_sort | abundance and occupancy use of a mesocosm to test pattern and process |
| topic | Mesocosm Drosophila simulans UCTD |
| url | http://hdl.handle.net/2263/27789 http://upetd.up.ac.za/thesis/available/etd-09062006-150712/ |