Exploration of climate mediated decline in a critically endangered southern hemisphere conifer over the last 40 years / Annabelle J. Rogers

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dc.contributor.advisorFebruary, Edmund Cen_ZA
dc.contributor.advisorVerboom, Tonyen_ZA
dc.contributor.authorRogers, Annabelle Jen_ZA
dc.date.accessioned2015-09-15T10:33:08Z
dc.date.available2015-09-15T10:33:08Z
dc.date.issued2013en_ZA
dc.description.abstractWiddringtonia cedarbergensis is a critically endangered conifer restricted entirely to the Cederberg Mountain range in the Western Cape of South Africa. This study aimed to assess whether contemporary climate change could be a driver in the recently documented tenfold decline of W. cedarbergensis in the last 40 years. By building distribution models using Maxent bioclimatic modelling for pre- and post- 1970’s point occurrence data, the distribution of the species pre- and post-1970’s were compared and assessed for significant change. Models predicted a clear range contraction in W. cedarbergensis from pre- to post- 1970. The present model predictions of suitability occur in a tight altitudinal band on the mid to upper slopes of the middle Cederberg (minimum of 1048m to a maximum of 1530m). However, the climatic predictions associate the present model distribution with relatively warmer and drier areas compared to that of the pre- 1970 model, suggesting a shift down slope rather than upslope. This is possibly due to the exaggeration of the upper limit of distribution for the pre-1970’s model that predicts W. cedarbergensis to occur as high as 1850m. This is unlikely due to the high prevalence of frost at this elevation. Though any climatic signal was complicated due to historical data error, high confidence in the present model prediction adds a valuable contribution to a body of literature that documents the decline of W. cedarbergensis and has important implications for conservation management of the species.en_ZA
dc.identifier.apacitationRogers, A. J. (2013). <i>Exploration of climate mediated decline in a critically endangered southern hemisphere conifer over the last 40 years / Annabelle J. Rogers</i>. (Thesis). University of Cape Town ,Faculty of Science ,Department of Biological Sciences. Retrieved from http://hdl.handle.net/11427/14023en_ZA
dc.identifier.chicagocitationRogers, Annabelle J. <i>"Exploration of climate mediated decline in a critically endangered southern hemisphere conifer over the last 40 years / Annabelle J. Rogers."</i> Thesis., University of Cape Town ,Faculty of Science ,Department of Biological Sciences, 2013. http://hdl.handle.net/11427/14023en_ZA
dc.identifier.citationRogers, A. 2013. Exploration of climate mediated decline in a critically endangered southern hemisphere conifer over the last 40 years / Annabelle J. Rogers. University of Cape Town.en_ZA
dc.identifier.ris TY - Thesis / Dissertation AU - Rogers, Annabelle J AB - Widdringtonia cedarbergensis is a critically endangered conifer restricted entirely to the Cederberg Mountain range in the Western Cape of South Africa. This study aimed to assess whether contemporary climate change could be a driver in the recently documented tenfold decline of W. cedarbergensis in the last 40 years. By building distribution models using Maxent bioclimatic modelling for pre- and post- 1970’s point occurrence data, the distribution of the species pre- and post-1970’s were compared and assessed for significant change. Models predicted a clear range contraction in W. cedarbergensis from pre- to post- 1970. The present model predictions of suitability occur in a tight altitudinal band on the mid to upper slopes of the middle Cederberg (minimum of 1048m to a maximum of 1530m). However, the climatic predictions associate the present model distribution with relatively warmer and drier areas compared to that of the pre- 1970 model, suggesting a shift down slope rather than upslope. This is possibly due to the exaggeration of the upper limit of distribution for the pre-1970’s model that predicts W. cedarbergensis to occur as high as 1850m. This is unlikely due to the high prevalence of frost at this elevation. Though any climatic signal was complicated due to historical data error, high confidence in the present model prediction adds a valuable contribution to a body of literature that documents the decline of W. cedarbergensis and has important implications for conservation management of the species. DA - 2013 DB - OpenUCT DP - University of Cape Town LK - https://open.uct.ac.za PB - University of Cape Town PY - 2013 T1 - Exploration of climate mediated decline in a critically endangered southern hemisphere conifer over the last 40 years / Annabelle J. Rogers TI - Exploration of climate mediated decline in a critically endangered southern hemisphere conifer over the last 40 years / Annabelle J. Rogers UR - http://hdl.handle.net/11427/14023 ER - en_ZA
dc.identifier.urihttp://hdl.handle.net/11427/14023
dc.identifier.vancouvercitationRogers AJ. Exploration of climate mediated decline in a critically endangered southern hemisphere conifer over the last 40 years / Annabelle J. Rogers. [Thesis]. University of Cape Town ,Faculty of Science ,Department of Biological Sciences, 2013 [cited yyyy month dd]. Available from: http://hdl.handle.net/11427/14023en_ZA
dc.language.isoengen_ZA
dc.publisher.departmentDepartment of Biological Sciencesen_ZA
dc.publisher.facultyFaculty of Scienceen_ZA
dc.publisher.institutionUniversity of Cape Town
dc.subject.otherBiological Sciencesen_ZA
dc.titleExploration of climate mediated decline in a critically endangered southern hemisphere conifer over the last 40 years / Annabelle J. Rogersen_ZA
dc.typeBachelor Thesis
dc.type.qualificationlevelHonours
dc.type.qualificationnameBSc (Hons)en_ZA
uct.type.filetypeText
uct.type.filetypeImage
uct.type.publicationResearchen_ZA
uct.type.resourceThesisen_ZA
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