http://hdl.handle.net/10500/2786 2013-05-19T05:30:51Z 2013-05-19T05:30:51Z Pasternak, Graham Brown, Leslie R. Kienzle, Stefan Fuller, Andrea Barrett, Louise Henzi, S. Peter http://hdl.handle.net/10500/8791 2013-03-16T22:00:32Z 2013-02-20T00:00:00Z

Population ecology of vervet monkeys in a high latitude, semi-arid riparian woodland Pasternak, Graham; Brown, Leslie R.; Kienzle, Stefan; Fuller, Andrea; Barrett, Louise; Henzi, S. Peter Narrow riparian woodlands along non-perennial streams have made it possible for vervet monkeys to penetrate the semi-arid karoo ecosystem of South Africa, whilst artificial water points have more recently allowed these populations to colonize much more marginal habitat away from natural water sources. In order to better understand the sequelae of life in these narrow, linear woodlands for historically 'natural' populations and to test the prediction that they are ecologically stressed, we determined the size of troops in relation to their reliance on natural and artificial water sources and collected detailed data from two river-centred troops on activity, diet and ranging behaviour over an annual cycle. In comparison to other populations, our data indicate that river-centred troops in the karoo were distinctive primarily both for their large group sizes and, consequently, their large adult cohorts, and in the extent of home range overlap in what is regarded as a territorial species. Whilst large group size carried the corollary of increased day journey length and longer estimated interbirth intervals, there was little other indication of the effects of ecological stress on factors such as body weight and foraging effort. We argue that this was a consequence of the high density of Acacia karroo, which accounted for a third of annual foraging effort in what was a relatively depauperate foristic habitat. We ascribed the large group size and home range overlap to constraints on group fission. Conservation implications: The distribution of group sizes, sampled appropriately across habitats within a conservation area, will be of more relevance to management than average values, which may be nothing more than a statistical artefact, especially when troop sizes are bimodally distributed. ABEERU

2013-02-20T00:00:00Z Myer, M.S. Harding, N. Fouchè, G. Faleschini, M.T. http://hdl.handle.net/10500/8790 2013-03-15T13:11:17Z 2013-02-01T00:00:00Z

Chemical profiling with cytokine stimulating investigations of Sutherlandia frutescens L. R. (Br.) (Fabaceae) Myer, M.S.; Harding, N.; Fouchè, G.; Faleschini, M.T. Sutherlandia frutescens, one of the medicinal plants of southern Africa, has been widely used to boost the immune system by various ethnic groups. This study aims to provide initial scientific evidence for in vitro immune modulating activities of extracts of S. frutescens on cytokines, including interleukins 4, 6, 8, 10, 12p70 and TNF produced by the HL60 cell lines, as well as to identify possible compounds present therein. This will assist in guiding further studies to an active compound. The chemical profile of extracts, fractions and compounds were determined using high performance liquid chromatography coupled to mass spectrometry. Results from the initial in vitro experiments conducted indicated that extracts from S. frutescens possessed immune modulating as well as anti-inflammatory activities. This in vitro study showed that an ethanolic extract appeared to recruit the various inflammatory cytokines to the site of infection upon stimulation with phorbol 12-myristate 13-acetate, where essentially the non-polar compounds present in the ethanol extract contributed to most of the activity observed for this extract. Unisa, CSIR

2013-02-01T00:00:00Z Robert F. Brand, Leslie R. Brown, Pieter J. du Preez http://hdl.handle.net/10500/5395 2012-06-14T17:20:48Z 2011-01-01T00:00:00Z

The Grassland vegetation of Platberg, eastern Free State, South Africa Robert F. Brand, Leslie R. Brown, Pieter J. du Preez Platberg is an inselberg that presents a refuge for indigenous plants and animals. Uncontrolled human access to this area threatens this sensitive ecosystem. The vegetation of Platberg was investigated to obtain an inventory of the different plant species and communities present in this area. A hierarchical classification, a description and an ecological interpretation of the grassland communities of Platberg are presented. A total of 169 sample plots were placed on a stratified random basis within the study area. From a TWINSPAN classification a total of 27 different plant communities, which can be grouped into two major community types, nine communities, 18 sub-communities and six variants, were identified. A significant difference in species richness was found between the two major communities, with the higher-altitude communities having a higher species richness than the communities on the lower-lying slopes. A total of 26 endemic or near endemic Drakensberg Alpine Centre species were recorded. Conservation implications: Anthropogenic influences are felt globally on ecosystems. Highaltitude habitats and organisms will be affected first. Inselbergs have high levels of endemic organisms and are reservoirs and refugia for unique genetic material. This grassland plant community survey of Platberg provides valuable information on inselberg ecology for conservation planning.

2011-01-01T00:00:00Z Robert F. Brand, Leslie R. Brown Pieter J. du Preez http://hdl.handle.net/10500/3843 2010-11-19T01:15:25Z 2010-01-01T00:00:00Z

A floristic analysis of the vegetation of Platberg, eastern Free State, South Africa Robert F. Brand, Leslie R. Brown; Pieter J. du Preez A checklist of vascular plants of Platberg was compiled to determine species richness, rarity and endemism. The floristic analysis is part of the Department of Economic, Tourism and Environmental Affairs Free State biodiversity assessment programme and conservation management plan for Platberg. The analysis identified a total of 669 species belonging to 304 genera and 95 families, with 214 species belonging to the Monocotyledoneae and 438 species to the Dicotyledoneae. The largest family is Asteraceae with 126 species, followed by Poaceae with 73 species, Cyperaceae with 39 species, Fabaceae with 33 species, and Scrophulariaceae with 27 species. Various fynbos species were found, as well as 26 endemic/near-endemic species belonging to the Drakensberg Alpine Centre or Eastern Mountain Region. The results of this study revealed that Platberg shares inselberg floral richness and endemism that can be tracked via the Afromontane archipelago-like string of inselbergs and mountains, which stretch north through the Chimanimani Mountains, into Malawi, the Eastern Arc Mountains via Tanzania and north through Ethiopia, into Eurasia. Conservation implications: Platberg, as an inselberg, is a site of significant biological diversity, with high species richness, vegetation selection and ecosystem complexity. It shares floral richness and endemism via inselbergs and mountains throughout Africa. The high species richness, Red Data species and ecosystems make this area an important conservation site that should be legislated and protected. ABEERU, Unisa

2010-01-01T00:00:00Z