Aim Alpine ecosystems differ in area, macroenvironment and biogeographical history across the Earth, but the relationship between these factors and plant species richness is still unexplored. Here, we assess the global patterns of plant species richness in alpine ecosystems and their association with environmental, geographical and historical factors at regional and community scales. Location Global. Time period Data collected between 1923 and 2019. Major taxa studied Vascular plants. Methods We used a dataset representative of global alpine vegetation, consisting of 8,928 plots sampled within 26 ecoregions and six biogeographical realms, to estimate regional richness using sample‐based rarefaction and extrapolation. Then, we evaluated latitudinal patterns of regional and community richness with generalized additive models. Using environmental, geographical and historical predictors from global raster layers, we modelled regional and community richness in a mixed‐effect modelling framework. Results The latitudinal pattern of regional richness peaked around the equator and at mid‐latitudes, in response to current and past alpine area, isolation and the variation in soil pH among regions. At the community level, species richness peaked at mid‐latitudes of the Northern Hemisphere, despite a considerable within‐region variation. Community richness was related to macroclimate and historical predictors, with strong effects of other spatially structured factors. Main conclusions In contrast to the well‐known latitudinal diversity gradient, the alpine plant species richness of some temperate regions in Eurasia was comparable to that of hyperdiverse tropical ecosystems, such as the páramo. The species richness of these putative hotspot regions is explained mainly by the extent of alpine area and their glacial history, whereas community richness depends on local environmental factors. Our results highlight hotspots of species richness at mid‐latitudes, indicating that the diversity of alpine plants is linked to regional idiosyncrasies and to the historical prevalence of alpine ecosystems, rather than current macroclimatic gradients.

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Two known aporphine alkaloids, (S)-dicentrine (1) and (S)-neolitsine (2), have been isolated from the MeOH extract of the aerial parts of Cissampelos capensis (Menispermaceae). The structures of these compounds were elucidated by NMR and MS analysis and comparison to literature data. These compounds were isolated by bioassay-guided fractionation using the Haemonchus contortus larval development assay. Compounds 1 and 2 exhibited EC90 values (concentration at which 90% loss of larval motility is observed) of 6.3 and 6.4 microg/mL, respectively. In an IN VIVO assay, administration of 1 resulted in 67% reduction of worm counts in mice at 25 mg/kg when dosed orally.

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.<p><strong>Conservation implications:</strong> 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.</p><p><strong>How to cite this article:</strong> Brand, R.F., Brown, L.R., du Preez, P.J., 2010, &lsquo;A foristic analysis of the vegetation of Platberg, eastern Free State, South Africa&rsquo;, <em>Koedoe</em> 52(1), Art. #710, 11 pages, DOI: 10.4102/koedoe.v52i1.710</p>