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Masubelele M.L.,Cape Research Center | Hoffman M.T.,University of Cape Town | Bond W.J.,South African Environmental Observation Network
Journal of Vegetation Science | Year: 2015

Questions: How has the vegetation of the major biomes (Grassland, Nama-karoo, Albany Thicket, Azonal) of southeastern South Africa changed over the course of the 20th century? How do changes in climate and land-use drivers relate to long-term changes in vegetation? What are the implications of these findings for land degradation hypotheses and future climate change projections for the region? Location: The biogeographically complex semi-arid, Karoo Midlands region of the southeastern part of South Africa. Methods: We re-photographed 65 historical landscape photographs, the majority of which dated from 1950 to 1970, to measure long-term changes in the cover of grasses, dwarf shrubs, tall shrubs and alien plants. The cover of each growth form as well as total vegetation cover was estimated from matched photograph pairs with the aid of detailed cover estimates recorded in the field. The change in cover was relativized between sites by dividing the difference in cover between the two time steps by the number of years between photographs, expressed as the percentage change in cover per decade. Significant changes in mean annual rainfall and the standardized precipitation index (SPI) from 27 climate stations were assessed using a Mann-Kendall test for trend. This non-parametric test was also used to assess the significance of long-term trends in the number of cattle, sheep and goats in each of the biomes over the period 1911-1996. Results: Grass cover and total vegetation cover had increased by between 1.0% to 4.5% per decade and 2.0% to 4.5% per decade, respectively, in all biomes investigated. In contrast, the cover of dwarf shrubs had decreased significantly by between 0.25% and 3.0% per decade, although not significantly so in the Nama-karoo biome. The change in tall shrub cover varied between different biomes but had generally increased in the study area. Alien plants were absent in the historical photographs and had increased significantly but only in Azonal habitats, where increases of 1.5% per decade were recorded. For the majority of climate stations no significant trend in mean annual rainfall and SPI values was recorded, while stocking rate had declined significantly in all biomes by between 36% and 48% from 1911 to 1996. Conclusions: The findings support the hypothesis that vegetation cover and condition has improved in the semi-arid regions of South Africa. These findings are discussed in light of future projections for the region. © 2015 International Association for Vegetation Science. Source


Swemmer L.,Scientific Services South African National Parks | Grant R.,Scientific Services South African National Parks | Annecke W.,Cape Research Center | Freitag-Ronaldson S.,Scientific Services South African National Parks
Society and Natural Resources | Year: 2015

More examples of positive and negative outcomes of community-based conservation initiatives aimed at benefit sharing are surfacing globally, and there is increasing interest in who wins and who loses at multiple scales. However, the term “benefit sharing” is not well defined in the context of protected areas, hindering the effective implementation thereof. We define benefit sharing as the process of making informed and fair trade-offs between social, economic, and ecological costs and benefits within and between stakeholder groups, and between stakeholders and the natural environment. We explore identifying appropriate benefits in certain contexts and monitoring benefit sharing initiatives using relevant qualitative and quantitative indicators. Finally, we use an illustrative case study of mopane worm harvesting from the Kruger National Park in South Africa to explore how benefit sharing as defined in the article can be implemented using a strategic adaptive management approach during the planning, assessment, and reporting phases. © 2015, Taylor & Francis Group, LLC. Source


Rebelo T.G.,South African National Biodiversity Institute | Freitag S.,Kruger National Park | Cheney C.,Table Mountain National Park | McGeoch M.A.,Cape Research Center
Koedoe | Year: 2011

Conservation requires that species are monitored to ensure the persistence of species and ecosystem processes. In areas with large numbers of threatened species, this can be a major challenge. Here we explore prioritising species of special concern on the Cape Peninsula, South Africa, conserved primarily in the Table Mountain National Park. With 307 terrestrial plant and animal species listed as threatened on the IUCN Red List (plus 208 as non-least concern) and 332 endemic to the Peninsula, it is impossible to monitor and manage all species with current resources. At a workshop of conservation managers and ecosystem and taxonomical specialists, 14 variables were incorporated into a simple scoring scheme to develop a priority listing of these species. Despite care to ensure that variables were independent, there was strong autocorrelation amongst biotic versus management variables. There was concern that biotic variables would be masked by management criteria, but this was not the case. We propose that monitoring should focus on as many top-scoring species as resources allow (including volunteers) and that setting a cut-off value for delimiting sensitive species should be eschewed. A major challenge is that many species are typical of lowland ecosystems, which are poorly represented in the national park. Although priority species for monitoring have been identified, this will need to be tempered with the monitoring costs and logistics of implementing the programme. Conservation implications: Owing to the large number of threatened and endemic species in the Cape Peninsula, it is impossible to monitor all species with current resources. Management must focus on ecosystem maintenance as species-focused management will inevitably result in conflict with other threatened species. Monitoring should focus on as many top-scoring species as resources allow. The costs and logistics of a monitoring programme still need to be worked out. © 2011. Source


Born C.,Stellenbosch University | Le Roux P.C.,Stellenbosch University | Le Roux P.C.,University of Helsinki | Spohr C.,Stellenbosch University | And 4 more authors.
Molecular Ecology | Year: 2012

Climatic conditions and landscape features often strongly affect species' local distribution patterns, dispersal, reproduction and survival and may therefore have considerable impacts on species' fine-scale spatial genetic structure (SGS). In this study, we demonstrate the efficacy of combining fine-scale SGS analyses with isotropic and anisotropic spatial autocorrelation techniques to infer the impact of wind patterns on plant dispersal processes. We genotyped 1304 Azorella selago (Apiaceae) specimens, a wind-pollinated and wind-dispersed plant, from four populations distributed across sub-Antarctic Marion Island. SGS was variable with Sp values ranging from 0.001 to 0.014, suggesting notable variability in dispersal distance and wind velocities between sites. Nonetheless, the data supported previous hypotheses of a strong NW-SE gradient in wind strength across the island. Anisotropic autocorrelation analyses further suggested that dispersal is strongly directional, but varying between sites depending on the local prevailing winds. Despite the high frequency of gale-force winds on Marion Island, gene dispersal distance estimates (σ) were surprisingly low (<10 m), most probably because of a low pollen dispersal efficiency. An SGS approach in association with isotropic and anisotropic analyses provides a powerful means to assess the relative influence of abiotic factors on dispersal and allow inferences that would not be possible without this combined approach. © 2011 Blackwell Publishing Ltd. Source


Foxcroft L.C.,South African National Parks | Foxcroft L.C.,Stellenbosch University | Mcgeoch M.,Stellenbosch University | Mcgeoch M.,Cape Research Center
Koedoe | Year: 2011

Adaptive management theory has attracted substantial interest in recent years, in natural resource management in general and also for invasive alien species management. However, whilst many theoretical and conceptual advances have been made, documented cases of practical applications are rare. Coupling invasive species management components with adaptive feedback processes is not without challenges, requiring a substantial change in the thinking and practice of all those involved. Drawing on a decade of experience in South African National Parks, we suggest an approach to implementing adaptive management for controlling invasive alien species. Whilst efforts have been made to advance components of the overall management strategy, the absence of a framework for decision making and feedback mechanisms, inflexibility in the system and shortcomings in the governance structure are all identified as barriers to learning and knowledge integration for the purposes of effective invasive alien species management. The framework provided here, encompassing documents, committees and processes, is aimed at addressing these shortcomings. © 2011. Source

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