Flowering is one of the most important stages in determining the successful survival and
spread in plants. The duration of the flowering period is closely associated with successful
reproduction, making it essential to understand the importance and effects of the length of
flowering on various macroecological variables across plant species. The effects of the length
of flowering periods on the distribution range size of species have seldom been investigated.
This project aims to identify any macroecological relationship that may exist between the
length of flowering periods and the distribution ranges of plant species endemic to the eastern
part of South Africa, a region well known for its floral diversity. Range size and flowering
phenology data were collected for several genera that are centred in the region (Cussonia,
Gymnosporia, Searsia, Streptocarpus, Pavetta, Plectranthus, Crinum, Eulophia, Gladiolus,
Kniphofia, Satyrium, Watsonia and Zantedeschia). At genus level, the relationship varied
considerably. While significant correlations between the two variables were retrieved in four
genera, the meaning of these patterns differed. In some cases, these suggested that a larger
range was achieved through successful pollination due to extended flowering periods,
whereas in others, it is probably just an effect of different flowering seasons in different areas
where the range is large enough to comprise diverse climates. When incorporating variables
such as growth form (narrowly and broadly-defined) and genus identity in analyses of covariance
between flowering durations and various measures of distribution, the association of
genera was far greater than that of growth form. It can be concluded that both range size and
the length of the flowering season are the result of numerous factors acting jointly, which
differ across plant groups and are likely to be susceptible to changes in climate and biological
invasions. This means that the relationship between range size and flowering period is driven
by different factors in different genera, suggesting that the conservation of plant diversity in
the face of global change will have to consider the complexity of flowering patterns, and it is
likely that lineage-specific approaches for different plant groups will be necessary. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2012.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:ukzn/oai:http://researchspace.ukzn.ac.za:10413/10129 |
| Date | 29 November 2013 |
| Creators | Mahadeo, Nikara. |
| Contributors | Ramdhani, Syd., Proches, Serban. |
| Source Sets | South African National ETD Portal |
| Language | en_ZA |
| Detected Language | English |
| Type | Thesis |
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