No abstract

Changes in the environment are first observed in changes in the vegetation. Vegetation survey, classification and mapping form the basis on which informed and scientifically defendable decisions on the environment can be taken. The classification and mapping of vegetation is one of the most widely used tools for interpreting complex ecosystems. By identifying different plant communities we are essentially identifying different ecosystems at a particular hierarchical level. Phytosociologists in Europe have been involved in such studies following, in particular, the Braun-Blanquet approach since the early 1900s. In South Africa, such studies were undertaken on a limited basis from the early 1970s and have since then steadily increased. The surveying of the enormous diversity of South African vegetation is one of the objectives of phytosociological studies. The demand for such data has steadily increased over the past few years to guide conservation policies, biodiversity studies and ecosystem management. In South Africa, numerous publications on the vegetation of conservation and other areas in the different biomes have been produced over the last few decades. However, vegetation scientists in South Africa experience unique problems. The purpose of this article is therefore to provide an overview of the history and the specific focus of phytosociological studies in South Africa and to recommend minimum requirements and methods to be followed when conducting such studies. It is believed that the incorporation of these requirements will result in scientifically justifiable research of high quality by phytosociologists in South Africa. Conservation implications: Effective conservation cannot be obtained without a thorough knowledge of the ecosystems present in an area. Consistent vegetation classifications and descriptions form the basis of conservation and monitoring exercises to maintain biodiversity. The incorporation of these guidelines and requirements will facilitate quality phytosociological research in South Africa

<strong>How to cite this article:</strong> Spear, D., McGeoch, M.A., Foxcroft, L.C. &amp; Bezuidenhout, H., 2011, ‘Alien species in South Africa’s national parks’, <em>Koedoe</em> 53(1), Art. #1032, 4 pages. doi:10.4102/koedoe.v53i1.103

As part of a vegetation survey programme for conservation areas in South Africa, the plant communities of the De Rust section of the Mountain Zebra National Park were investigated. From a TWINSPAN classification, refined by Braun-Blanquet procedures, 14 plant communities, which can be placed into six major groups, were identified. A clas- sification and description of these communities, as well as a vegetation map are presented. Associated gradients in habitat were identified by using an ordination algorithm (DECORANA). The diagnostic species as well as the prominent and less conspicuous species of the tree, shrub, herb and grass strata are outlined

No abstract

African savannas are characterised by temporal and spatial fluxes that are linked to fluxes in herbivore populations and vegetation structure and composition. We need to be concerned about these fluxes only when management actions cause the system to shift towards a less desired state. Large herbivores are a key attribute of African savannas and are important for tourism and biodiversity. Large protected areas such as the Kruger National Park (KNP) manage for high biodiversity as the desired state, whilst private protected areas, such as those adjacent to the KNP, generally manage for high income. Biodiversity, sustainability and economic indicators are thus required to flag thresholds of potential concern (TPCs) that may result in a particular set of objectives not being achieved. In large conservation areas such as the KNP, vegetation changes that result from herbivore impact, or lack thereof, affect biodiversity and TPCs are used to indicate unacceptable change leading to a possible loss of biodiversity; in private protected areas the loss of large herbivores is seen as an important indicator of economic loss. Therefore, the first-level indicators aim to evaluate the forage available to sustain grazers without deleteriously affecting the vegetation composition, structure and basal cover. Various approaches to monitoring for these indicators were considered and the importance of the selection of sites that are representative of the intensity of herbivore use is emphasised. The most crucial step in the adaptive management process is the feedback of information to inform management decisions and enable learning. Feedback loops tend to be more efficient where the organisation’s vision is focused on, for example, economic gain, than in larger protected areas, such as the KNP, where the vision to conserve biodiversity is broader and more complex.<p><strong>Conservation implications:</strong> In rangeland, optimising herbivore numbers to achieve the management objectives without causing unacceptable or irreversible change in the vegetation is challenging. This manuscript explores different avenues to evaluate herbivore impact and the outcomes of management approaches that may affect vegetation.</p><p><strong>How to cite this article:</strong> Grant, R.C.C., Peel, M.J.S. &amp; Bezuidenhout, H., 2011, ‘Evaluating herbivore management outcomes and associated vegetation impacts’, <em>Koedoe</em> 53(2), Art. #1008, 15 pages. doi:10.4102/koedoe.v53i2.1008</p>

Diverse political, cultural and biological needs epitomise the contrasting demands impacting on the mandate of the South African National Parks (SANParks) to maintain biological diversity. Systems-based approaches and strategic adaptive management (learn by doing) enable SANParks to accommodate these demands. However, such a management strategy creates new information needs, which require an appropriate analytical approach. We use conceptual links between objectives, indicators, mechanisms and modulators to identify key concerns in the context of and related to management objectives. Although our suggested monitoring designs are based mostly on defined or predicted underlying mechanisms of a concern, SANParks requires inventory monitoring to evaluate its key mandate. We therefore propose a predictive inventory approach based on species assemblages related to habitat preferences. Inventories alone may not always adequately serve unpacking of mechanisms: in some cases population size needs to be estimated to meet the information needs of management strategies, but actual population sizes may indirectly affect how the species impact on other values. In addition, ecosystem objectives require multivariate assessments of key communities, which can be used in trend analysis. SANParks therefore needs to know how to detect and define trends efficiently, which, in turn, requires precision of measures of variables. <p><strong>Conservation implications:</strong> Current research needs with regard to monitoring should focus on defining designs to yield optimal precision whilst taking methodology, survey trade-offs and analytical approaches into account. Use of these directives and research will guide monitoring during evaluation of SANParks objectives at various scales.</p><p><strong>How to cite this article:</strong> Ferreira, S., Deacon, A., Sithole, H., Bezuidenhout, H., Daemane, M. &amp; Herbst, M., 2011, ‘From numbers to ecosystems and biodiversity: A mechanistic approach to monitoring’, <em>Koedoe </em>53(2), Art. #998, 12 pages. doi:10.4102/koedoe.v53i2.998</p>

As part of a larger project to assess the vegetation dynamics and conservation potential of the enlarged Mountain Zebra National Park, a checklist was produced to determine the plant species richness for this area. Six hundred and eighty species, represented by 333 genera and 87 families were identified. One hundred and eighty species belong to the Monocotyledoneae and 479 species to the Dicotyledoneae. By far the largest families are the Asteraceae with 129 and the Poaceae with 82 species. Thirteen Red Data species were recorded. A number of fynbos elements were encountered, the most noteworthy being two families endemic to the Cape Floristic Region, the Penaeaceae and Grubbiaceae. A very high species to square kilometre ratio of 5.05 supports the area’s rich floristic composition