A5069196157- Ecology and Vegetation Dynamics Studies
- Plant Diversity and Evolution
- Geology and Paleoclimatology Research
- Plant Taxonomy and Phylogenetics
- Pleistocene-Era Hominins and Archaeology
- Plant and animal studies
- Botany and Plant Ecology Studies
- Fire effects on ecosystems
- Species Distribution and Climate Change
- Genetic diversity and population structure
- African Botany and Ecology Studies
- Rangeland and Wildlife Management
- Evolution and Paleontology Studies
- Plant Water Relations and Carbon Dynamics
- Archaeology and ancient environmental studies
- Remote Sensing and LiDAR Applications
- Genetic Mapping and Diversity in Plants and Animals
- Archaeology and Rock Art Studies
- Coastal wetland ecosystem dynamics
- Genetic and phenotypic traits in livestock
- Soil Carbon and Nitrogen Dynamics
- Soil Geostatistics and Mapping
- Plant and Fungal Species Descriptions
- Horticultural and Viticultural Research
- Ziziphus Jujuba Studies and Applications
Nelson Mandela University
2015-2025
University of Cape Town
2009-2017
Swedish Museum of Natural History
2013
Summary The fields of phylogenetic tree and network inference have dramatically advanced in the past decade, but independently with few attempts to bridge them. Here we provide a framework, implemented phangorn library R, transfer information between trees networks. This includes: (i) identifying labelling equivalent branches edges, (ii) transferring branch support (iii) mapping bipartition from sample (e.g. bootstrapping or Bayesian inference) onto edges. ability readily combine should lead...
Abstract Aim Although all five of the major mediterranean‐climate ecosystems ( MCE s) world are recognized as loci high plant species diversity and endemism, they show considerable variation in regional‐scale richness. Here, we assess role stable Pleistocene climate Cenozoic topography explaining regional richness globe's s. We hypothesize that older, more climatically s would support species, because have had time for to accumulate than were historically subject greater topographic...
Abstract Oxalic acid is one of the most abundant organic acids produced by plants. Much global production oxalic deposited on soil surfaces in leaf litter to be oxidized microorganisms, resulting a pH increase and shifting carbonate equilibria. In what known as oxalate-carbonate pathway, calcium oxalate metabolism results CO2 being sequestered into soils insoluble calcite (CaCO3). There growing appreciation that scale this process sufficiently large an important contribution carbon turnover...
Abstract. The Coexistence Approach has been used to infer palaeoclimates for many Eurasian fossil plant assemblages. However, the theory that underpins method never examined in detail. Here we discuss acknowledged and implicit assumptions assess statistical nature pseudo-logic of method. We also compare with active field species distribution modelling. argue will inevitably be violated some degree lacks any substantive means identify or quantify these violations. absence a framework makes...
High-impact mega-fires in many temperate forests and shrublands of the world have called for pre-emptive approaches to mitigate fire risk. Comparative appraisals characteristics flammability plant fuels can inform risk predictions vegetation management efforts wildland-urban interface such fire-prone regions. Prompted by recent extreme fires Cape Floristic Region South Africa, we assessed fuel traits excised terminal branches 30 woody species (many which never been studied before) that...
Nuclear DNA is widely used to estimate phylogenetic and phylogeographic relationships. gene variants may be present in an individual's genome, these result Intra-Individual Site Polymorphisms (2ISP; pronounced "twisp") direct-PCR or individual-consensus sequences based on a sample of clones fragment from next generation sequencing (NGS). 2ISPs can occur fairly often, especially within, but not restricted to, high-copy-number regions such as the internal transcribed spacers nuclear ribosomal...
The causes and consequences of plant flammability are a contested issue. In fire-prone ecosystems, high is invoked as trait (in combination with fire-survival traits) that enhances reproductive success reduces competition in the post-fire environment. On other hand, may be consequence selective forces, for example, deterring herbivores. Here, we use standardised method estimating flammabilities 99 species distributed across five biomes small area southwestern Cape Floristic Region, South...
Landscapes of the eastern Cape Floristic Region are extremely rich in biomes. Analysis determinants boundaries between biomes can generate insights and predictions that useful for applied ecological sciences. Here we used a historical data set multivariate methods to explore Forest, Fynbos, Grassland, Renosterveld Thicket 1200 km2 area Kouga region. The comprised 203 (10 m × 10 m) sites with corresponding landscape-scale environmental variables, 100 site-bound edaphic (physical chemical)...
Abstract Aim The sub‐escarpment coastal plains of South Africa provide remarkable opportunities to study the determinants biome boundaries as numerous biomes are found closely juxtaposed, including Nama‐Karoo semi‐desert shrubland and Albany subtropical thicket. is centred on semi‐arid frosty high‐elevation interior plateau Africa, whereas thicket inhabits comparatively warmer plains. We examined role winter frosts in determining between these two plain. Location Kaboega, Eastern Cape,...
Numerous shrublands exist in areas where soil moisture should support tree growth. In South Africa, the dwarf of Nama-Karoo biome and tree-dominated vegetation Albany Subtropical Thicket share a boundary that is often abrupt. This not associated with edaphic or rainfall transitions. Field observations leaf-level experiments suggest vulnerability thicket species to frost damage responsible for this thicket–shrubland boundary. We tested hypothesis by establishing cuttings Portulacaria afra...
Abstract Despite the emergence of a general conceptual framework for woody tree response to drought, few studies link variation in functional traits coexisting species drought outcomes diverse plant communities. We use natural event test an ecological prediction from embolism avoidance hypothesis: that co-existing single growth form (woody trees) will converge upon avoid during all but most severe droughts. evaluated hydraulic and responses six common South Africa’s Albany Subtropical...
Aspalathus linearis (Fabaceae) is endemic to the Cape Floristic Region in Western and Northern Provinces of South Africa. The reddish leaves stems, primarily one cultivar, are used make a commercially important tea which marketed locally internationally as 'rooibos' or 'redbush' tea. In historical times rooibos was collected wild. twentieth century cultivation single cultivar increasingly replaced wild harvest meet growing demand. Recently, from forms species, vary significantly growth form...
Abstract Aim Southern Africa lacks the palaeo‐archives needed to infer regional vegetation history. The megadiverse subtropical thicket of South Africa, locally termed Albany ( AST ), is postulated have experienced severe reductions in range during Pleistocene glacial periods. Here we test this contraction hypothesis using spatial predictions from climate envelope models explore distributions subtypes at Last Glacial Maximum LGM ). Location Africa. Methods We used an ensemble approach assess...
Seedlings of woody canopy species in the xeric forms subtropical thicket are rare. Here we argue that low number seedlings is a consequence niche conservatism where have retained germination and seedling establishment requirements associated with their ancestral origins warm, wet forests early Cenozoic. We test this hypothesis by evaluating success 12 arid valley – representing range growth dispersal modes using factorial experiment sought to simulate permanently moist deeply-shaded...
The glacial–interglacial climate cycles of the Pleistocene played a significant role in dramatically altering species distributions across globe. However, Greater Cape Floristic Region is thought to have been decoupled from global fluctuations and current Mediterranean remained relatively buffered during this period. Here we explore roles stability topographic complexity region on range history an endemic Little Karoo plant, Berkheya cuneata, using ensemble distribution modelling multi-locus...
Many endemic Cape plant species are commercially valuable, but information required to manage the resources is often lacking. Here I consider potential genetic risk that transition cultivation may pose for plants and use honeybush – which based on members of genus Cyclopia as an example. The industry expanding, in part driven by from wild harvesting cultivation. This change offers substantial environmental economic benefits risks populations through contamination. discuss (1) importance...