The aim of this paper is to provide an overview of the semantic and syntactic characteristics of the discourse marker actually, and then to describe and explain how it is used by mothertongue (MT) Xhosa speakers who have learned English as an additional language. Such a description may provide a useful benchmark for comparison with MT norms. The source of data for the study is a corpus of approximately half a million words of transcribed spontaneous dialogue between Xhosa English speakers.

An estimated 27 million South Africans use indigenous medicines (Mander, 1997, Medicinal plant marketing and strategies for sustaining the plant supply in the Bushbuckridge area and Mpumalanga Province. Institute for Natural Resources, University of Natal, Pietermaritzburg, South Africa). Although herbal remedies are freely available in amayeza stores, or Xhosa chemists, for self-medication, little is known about the motivations of consumers. According to African belief systems, good health is holistic and extends to the person's social environment. The paper makes a distinction between traditional medicines which are used to enhance personal well-being generally and for cultural purposes, on the one hand, and medicines used to treat physical conditions only, on the other. Drawing on an eight-month study of Xhosa chemists in Eastern Cape Province, South Africa, in 1996, the paper identifies 90 medicines in stock which are used to enhance personal well-being. Just under one-third of all purchases were of medicines to enhance well-being. Remedies particularly popular included medicines believed to ward off evil spirits and bring good luck. The protection of infants with medicines which repel evil spirits is a common practice. Consumer behaviours indicate that the range of medicines available is increased by indigenisation of manufactured traditional medicines and cross-cultural borrowing. Case studies confirm that self- and infant medication with indigenous remedies augmented by indigenised medicines plays an important role in primary health care by allaying the fears and anxieties of everyday life within the Xhosa belief system, thereby promoting personal well-being.

This article considers the use of popular science articles in teaching scientific literacy. Comparing the discourse features of popular science with research article and textbook science – the last two being target forms for students – it argues that popular science articles cannot serve as models for scientific writing. It does, however, suggest that popular articles can make science more accessible to students, and so can play a useful role in the teaching of scientific writing as well as in the teaching of science. This is because popular science articles view scientific findings as provisional rather than as incontrovertible fact as they are presented in textbooks or as they appear to be presented in research articles. Another feature of popular articles is that they are peopled with large numbers of specific scientists, thus representing scientists as ordinary people rather than as a few exceptional people of iconic status as is the case in textbooks.

During the past decade the relationship between biodiversity and human diversity has received increased attention, resulting in the identification of what the Declaration of Belém calls an ‘inextricable link’ between biological and cultural diversity. Although the term biocultural diversity, introduced to denote this link, is being used increasingly, there has been little critical reflection on what it precisely refers to. I argue that it is used with particular reference to ‘indigenous traditional’ people, but that there is scope for extending its application within biocultural discourse. I therefore review the concept of culture and discuss what constitutes cultural values of the natural environment. I conclude that the concept of culture must be understood as involving a dynamic process of transcultural exchange and constant re-articulations of tradition resulting in the persistence of certain cultural practices. This approach ultimately reveals that the concept of biocultural diversity is also applicable to non-indigenous traditional communities.

The paper provides a sketch of the discourse of media and ‘cyber-democracy’ in and out of Africa. Firstly, it discusses the characteristic features of new media technology. Secondly, it attempts a ‘theorising’ of cyber-democracy, within the context of general democratic theory. Thirdly, it sets out a vision of cyber-democracy for Africa. In delineating this vision, it highlights six features characteristic of the democratic potential of new media technology and gives examples of how Africa has appropriated them. Finally, it outlines a ‘new media’ research agenda for Africa.

This background paper discusses some of the key issues associated with the phenomenon of public service broadcasting (PBS) in selected sub-Saharan African countries. These issues include (i) the conceptualisation of PSB (ii) the international politico-juridical context for PSB (iii) the regulatory-cum-policy models for PSB and (iv) the funding models for PSB.

In sharp contrast to the debates concerning land policy, land tenure and sustainable resource management in South Africa is any input concerning the geographical distribution of land productivity. This paper attempts to redress this imbalance by providing an empirical investigation of land potential in South Africa. In this way we intend to provide the crucial context for policy and academic studies of the land issue in South Africa. Furthermore, we will undertake our study in such a way that comparison can be made to Zimbabwe and Kenya where the land issue has been such a critical component of the post-colonial development process. Theoretically our work is contextualised within the debates surrounding the importance of geographical endowments, institutions and policies in the development process.

A reverse-flow micellar electrokinetic chromatographic (RF-MEKC) method was developed for the simultaneous qualitative determination of 10 components consisting of the flavonol glycosides, rutin and quercitrin, the flavonol aglycones, isorhamnetin, kaempferol and quercetin, the terpene trilactones, ginkgolides A, B, C and J and the sesquiterpene, bilobalide. This method was used to fingerprint Ginkgo biloba solid oral dosage forms and validated for the quantitation of the marker compounds, rutin and quercetin in some commercial products. In addition to the usual variables, the influence of some essential background electrolyte (BGE) components such as sodium dodecyl sulphate (SDS) and <beta>-cyclodextrin concentrations were investigated. A polyimide fused-silica square capillary column (75 μm I.D. × 360 μm O.D.) with a total length of 60.0 cm and effective length of 45.0 cm was used for the separation. The final BGE consisted of 20 mM phosphoric acid, 40 mM SDS and 12 mM <beta>-cyclodextrin (pH 2.2) using reverse polarity with a voltage of −17.5 kV. Samples were injected electrokinetically at −5 kV for 3 s for the qualitative analysis and hydrodynamically at 20 mbar for 0.6 s for the quantitative assay. The total run time was 22 min and the limits of detection were 3.13 μg/ml and 1.88 μg/ml for rutin and quercetin, respectively. Fingerprint profiles of the solid oral dosage forms and the results of the quantitative analysis indicated that there were major discrepancies in the marker content between products and illustrates the value of this method for use as a procedure to assess product quality of commercially available Ginkgo biloba products.

The mussel Mytilus galloprovincialis is invasive worldwide, has displaced indigenous species on the west coast of South Africa and now threatens Perna perna on the south coast. We tested the hypothesis that Mytilus will replace Perna by examining changes in their distribution on shores where they co-exist. Total cover, adult density, recruit density, recruit/adult correlations and mean maximum lengths of both species were measured in 2001 at two contrasting sites (Plettenberg Bay and Tsitsikamma) 70 km apart, each including two locations 100 m apart. Cover and density were measured again in 2004. Total mussel abundance was significantly lower in Tsitsikamma, and recruit density was only 17% that of Plettenberg Bay. Abundance and cover increased upshore for Mytilus, but decreased for Perna, giving Mytilus higher adult and recruit density and total cover than Perna in the upper zones. Low shore densities of recruits and adults were similar between species but cover was lower for Mytilus, reflecting its smaller size, and presumably slower growth or higher mortality there. Thus, mechanisms excluding species differed among zones. Recruitment limitation delays invasion at Tsitsikamma and excludes Perna from the high shore, while Mytilus is excluded from the low shore by post-recruitment effects. Recruitment limitation also shapes population structure. Recruit/adult correlations were significant only where adult densities were low, and this effect was species-specific. Thus, at low densities, larvae settle or survive better near adult conspecifics. After 3 years, these patterns remained strongly evident, suggesting Mytilus will not eliminate Perna and that co-existence is possible through partial habitat segregation driven by recruitment limitation of Perna on the high shore and post-settlement effects on Mytilus on the low shore.

Channel instability has occurred in the Bell River in the form of meander cutoffs, a number of which have occurred since 1952. Increased sediment loading from widespread gully erosion in the catchment has been proposed as the trigger for this instability. Willow species of the Salix family, in particular S. caprea, have been planted along the banks in an effort to prevent further channel shifting. This study reports the results of an investigation into the effect of vegetation on channel form and stability over a 17 km stretch of channel. Results indicate that riparian vegetation has significant effects on channel form which have implications for channel stability. Riparian vegetation increases bank stability and reduces channel cross-sectional area, thereby inducing stability at flows less than bankfull. Evidence indicates that narrow stable stretches are associated with relatively high levels of riparian vegetation. Wider, unstable channels are associated with relatively less riparian vegetation. The effectiveness of riparian vegetation relative to bank sediments was investigated. A dense growth of willows was found to have an equivalent effect to banks with a silt-clay ratio of about 70 per cent. The channel narrowing induced by vegetation may contribute to channel shifting at high flows. The reduced channel capacity is thought to result in more frequent overbank flooding which may ultimately lead to channel avulsion. Thus where increased sediment loading is pushing the channel towards instability, vegetation may be effective in imparting local stability, but it is unable to prevent long-term channel shifts, and may rather help to push the system towards more frequent avulsions.