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Summary: Knowledge of ecological patterns and processes is key to effective conservation of biodiversity hotspots under threat. Renosterveld is one of the most critically endangered habitats in the biologically unique Cape Floristic Region, South Africa. For the first time, we map and synthesize the current state of knowledge on renosterveld ecology and conservation. We investigated 132 studies for the themes, locations and taxa of renosterveld research and the fragmentation, threats, recommendations and barriers to renosterveld conservation. More studies focused on plants than any other taxa (48% of articles) and are conducted mostly in larger, intact renosterveld fragments. The most commonly identified threat to renosterveld was agricultural intensification; conservation recommendations spanned improved farming practices, formal protection and local patch management. Conservation implementation has been piecemeal and has depended largely on the goodwill of landowners, which can be constrained by costs of conservation measures and a lack of suitable restoration means. Citizen science is a promising potential solution to some barriers. Fragmented knowledge in such a transformed and relatively densely populated region highlights the scale of knowledge gaps for other biodiversity hotspots and has implications for ongoing conservation work. [ABSTRACT FROM AUTHOR]

Commercial plantations and alien tree invasions often have substantial negative impacts on local biodiversity. The effect of plantations on faunal communities in the fire‐adapted fynbos vegetation of the Cape Floristic Region biodiversity hotspot is not yet well quantified. We studied small mammal community structure in alien Pinus radiata plantations and adjacent fynbos regenerating after clear‐felling of plantations on the Cape Peninsula, South Africa. Small mammal sampling over 1,800 trap‐nights resulted in 480 captures of 345 individuals (excluding recaptures) representing six species. Significantly more species, individuals (12 X) and biomasses (29 X) of small mammals occurred on recovering fynbos sites compared to plantations. This was commensurate with a higher diversity of plant growth forms, vegetation densities and live vegetation biomass. Only one small mammal species, the pygmy mouse (Mus minutoides), was consistently trapped within plantations. Fynbos sites were dominated by three small mammal species that are ecological generalists and early successional pioneer species, rendering the recovering fynbos slightly depauperate in terms of species richness and evenness relative to other studies done in pristine fynbos. We make three recommendations for forestry that would facilitate the restoration of more diverse natural plant communities and progressively more diverse and dynamic small mammal assemblages in a key biodiversity hotspot. [ABSTRACT FROM AUTHOR]

The South African Fynbos is the smallest floristic kingdom with high levels of endemism and where fire dominates the landscape. However, drivers of soil microbial distribution and diversity are still poorly understood. This study aims to highlight the biogeographical patterns of bacterial and fungal communities and elucidate the mechanisms that mediate their distribution. Soil samples were collected from four Fynbos vegetation types and microbial dynamics were examined using Illumina sequencing of the 16S rRNA bacterial gene and fungal ITS region. Bacterial alpha diversity significantly varied across all Fynbos vegetation types, whilst only the fungal community structure was significantly influenced by vegetation types and environmental variables. The relative abundance of major phyla was similar across all Fynbos types with the exception of Gemmatimonadetes, Cyanobacteria, Ascomycota and Zygomycota. Lastly, neutral models were the best predictor of the abundance and distribution of operational taxonomic units (OTUs) across all Fynbos vegetation types, suggesting that during the winter months dispersal limitations play a role in microbial community assembly. Overall, taken together with previous studies from the region, this study provides novel insight into the processes that modulate the biogeographical patterns of soil microbes and contributes to our knowledge of factors that mediate microbial ecology in diverse ecosystems. [ABSTRACT FROM AUTHOR]

The South African Cape fynbos heath Erica coccinea subsp. coccinea is polymorphic for post-fire regeneration mode (seeder/resprouter), flower colour (red/yellow), flowering time (summer-autumn/winter-spring), as well as anther size. These polymorphisms tend to occur between, rather than within, populations. Here, we aimed to understand flower colour divergence in this fynbos heath species and its association with post-fire regeneration. We tested for an association between these polymorphisms. We also examined whether yellow-flowered plants lacked anthocyanins and whether the lack of anthocyanins affected the concentration of other flavonoids, both in flowers and shoots. We found a strong association between flower colour, regeneration mode and flowering phenology. We also detected larger anthers and larger pollen in yellow- than in red-flowered plants, consistently for both resprouter and seeder regeneration strategies. Finally, we ascertained that being yellow-flowered is associated with loss in the capacity of synthesizing anthocyanins in both the flower and in the vegetative tissue. Considering that pollinator availability or preferences do probably not constitute a selection pressure, we propose that both enhanced reproductive success of anthocyaninless, yellow-flowered plants and the avoidance of likely negative pleiotropic effects (early senescence) in seeders would be key to understanding the flower colour divergence in E. coccinea subsp. coccinea. [ABSTRACT FROM AUTHOR]

De Fynne Nursery, a black-owned agribusiness, has cemented a unique position in South Africa’s indigenous plants industry against all odds. With an undying passion for the horticulture industry, Jacky Goliath and Elton Jefthas, De Fynne’s cofounders, continue to live the dream that began in their backyard. Today, they sit in their new 22-hectare farm and muse over strategic decisions as they navigate the challenges of doing business in an emerging economy. This case study focuses on opportunities and challenges for De Fynne as it pushes into its next growth phase by looking at the changing competitive landscape, the balance between marketing existing products and innovating new products, and ways to become operationally efficient and profitable in both its nursery and the farm.

The Acidobacteria is one of the most abundant phyla in most soil types. Fynbos plants are endemic to South Africa, and these soils provide the ideal habitat for Acidobacteria, because of its low pH and oligotrophic properties. However, little is known about their distribution in the fynbos biome and the impact of cultivation of plants on Acidobacterial diversity. Therefore, the aim of this study was to determine the effect of seasonal changes and cultivation on the relative abundance and diversity of Acidobacteria associated with Aspalathus linearis (rooibos) and Cyclopia spp. (honeybush). This study was based on rhizosphere soil. A total of 32 and 31 operational taxonomic units (OTUs) were identified for honeybush and rooibos, respectively. The majority of these were classified as representatives of subdivisions 1, 2, 3, and 10. Significant differences in community compositions were observed between seasons for both honeybush and rooibos, as well as between the cultivated and uncultivated honeybush. Acidobacteria had a significantly positive correlation with pH, C, Ca2+, and P. In this study, we have shown the effect of seasonal changes, in summer and winter, and cultivation farming on the relative abundance and diversity of Acidobacteria present in the soil of rooibos and honeybush.

The Cape Floristic Region (CFR) is globally known for its plant biodiversity, and its flora is commonly referred to as fynbos. At the same time, this area is under severe pressure from urbanization, agricultural expansion and the threat of invasive alien plants. Acacia, Eucalyptus and Pinus are the common invasive alien plants found across the biome and considerable time, effort and resources are put into the removal of invasive alien plants and the rehabilitation of native vegetation. Several studies have shown that invasion not only affects the composition of plant species, but also has a profound effect on the soil chemistry and microbial populations. Over the last few years, a number of studies have shown that the microbial populations of the CFR are unique to the area, and harbour many endemic species. The extent of the role they play in the invasion process is, however, still unclear. This review aims to provide an insight into the current knowledge on the different microbial populations from this system, and speculate what their role might be during invasion. More importantly, it places a spotlight on the lack of information about this process.

The legume Acacia mearnsii invades South Africa's fynbos riparian zones and may alter the nitrogen (N) dynamics and supply in these areas that typically support few native N fixers. Nitrogen uptake by A. mearnsii may also be influenced by water availability, potentially affecting riparian-specific performance and impact estimations. We expected to find functional differences between the invasive legume and the two co-occurring but non-leguminous native species Brabejum stellatifolium and Metrosideros angustifolia. We also wanted to examine whether in-situ water availability affected N source or uptake in the invasive species. We found A. mearnsii was indeed functioning differently from non-N-fixing native species, and had considerably higher foliar %N. Interestingly, 15N abundance and uptake were associated with site hydrology, meaning water availability should be scrutinised when assuming N-fixing in A. mearnsii using δ15N. Nonetheless, higher water availability to A. mearnsii in fynbos riparian ecosystems did increase foliar N uptake. This has implications for prioritizing clearing of sites with increased nutrient deposition, such as dense stands in relatively moist riparian zones. [ABSTRACT FROM AUTHOR]

Abstract: The canopies of many tree species sustain a large diversity of folivorous arthropods and phytopathogenic fungi. These organisms are thought to influence overall tree and stand productivity. Leaf diseases caused by Phyllosticta owaniana and Periconiella velutina, phytopathogenic fungi commonly found on the native riparian tree Brabejum stellatifolium (wild almond), like any other leaf disease, can potentially reduce a plant's photosynthetic efficiency. In addition to these two phytopathogens, the weevils Setapion provinciale and Setapion quantillum are abundant in wild almond canopies. Despite their pervasive occurrence, the impacts of these phytopathogens and arthropods on host tree leaf physiology have not been examined. The gas exchange response of wild almond leaves to phytopathogens and folivore damage was assessed. Leaf nitrogen, phosphorus and water content were also determined. Declines in photosynthetic rates and other physiological parameters were associated with increasing damage severity by weevils and phytopathogens in leaves of B. stellatifolium. Nitrogen and phosphorus contents were negatively associated with disease severity. Water and phosphorus contents were also negatively correlated with increased weevil damage, while nitrogen content was positively correlated with it. The observed responses of B. stellatifolium metabolic functioning to fungal pathogen and folivory indicate a possibility of suppressed wild populations of wild almond. [ABSTRACT FROM AUTHOR]

Abstract: How do many species coexist within a trophic level? Resource niches are the classical answer, but in plants which share a small set of abiotic resources, the possibilities for resource partitioning are limited. One possible explanation is that plant species have different pollination niches, with each species specialized to a subset of the available animal species. If this pollinator partitioning results in negative frequency dependence such that each plant species’ reproduction is reduced when it becomes abundant, pollination niches could maintain plant diversity, provided that the strength of negative frequency dependence is sufficient to overcome fitness inequalities between species. We tested this idea by quantifying the effect of species relative abundance on pollinator visitation rate in a 7,000 m2 plot of South African Fynbos vegetation. In addition, we quantified the effect of intraspecific abundance variation at a smaller spatial scale (9 m2 plots), documented species’ pollination niches, and tested the importance of pollinators for seed set in a subset of the plant species. We found that visitation rate indeed declined sharply across the 33 plant species with increasing abundance, but visitation rate was also somewhat depressed in very rare species such that the resulting relationship between visitation rate and relative abundance was hump‐shaped. Pollinator niche partitioning among plant species was evident, but less pronounced than in many other studies. Visitation rate was slightly higher in more generalized species, suggesting that they have access to a larger pollination resource. At the intraspecific level and smaller spatial scale, results were less clear and varied among species. Pollinators enhanced seed set in most species. Synthesis. The results imply that, above an abundance threshold, intraspecific competition for pollination could limit the reproduction of common species, thus promoting plant species coexistence. However, the rarest plant species could become extinct due to pollen limitation, that is, an Allee effect. In addition, interactions with pollinators may introduce frequency‐independent fitness differences between plant species, thereby increasing the strength of negative frequency dependence required for stable coexistence. These findings shed new light on the role of the pollination niche in plant coexistence. [ABSTRACT FROM AUTHOR]

Non-native vegetation in the riparian zone impacts on water temperatures, flow patterns, degree of shading, channel modification, and changes to natural sediment loads. Freshwater ecosystems in the Garden Route Initiative planning domain are of particular conservation value, because of the rich Gondwanaland relict aquatic macroinvertebrate fauna found in the rivers there, which are vulnerable to thermal changes. Data were collected during 2013 and 2014 at 19 sites on seven river systems between George and Knysna in the southern Cape, South Africa. These included 12 months of hourly water temperatures at all sites, and quantitative sampling of aquatic macroinvertebrates at ten sites. Each site was characterised in terms of water quality (pH, conductivity and turbidity) and general characteristics, including impacts such as density of non-native riparian trees. At the family level, aquatic macroinvertebrate communities showed variation between sites and seasons. Differences were more pronounced on the basis of natural land cover type (fynbos versus indigenous forest) than densities of non-native invasive riparian vegetation. Conservation of these river systems will depend on maintaining a mosaic of natural vegetation types. [ABSTRACT FROM AUTHOR]

Abstract The lack of examples of hybridisation within South African Cape Fynbos lineages gives the impression that interspecific hybridisation events may be rare in this system. If this is the case, then long-distance translocations of plant species across the Cape are unlikely to have any impact on the genetic component of biodiversity. Here we demonstrate that local populations of Protea eximia have hybridised with the non-local and introduced Protea susannae at Van Stadens Wildflower Reserve using morphological and genetic data; DNA sequence data were obtained from the internal transcribed spacer from the nuclear ribosomal cistron and a noncoding region of the chloroplast. Of the 24 plants from the reserve that were analysed, 11 were identified as hybrids, and comparing nuclear and chloroplast signals indicated bidirectional gene-flow between these species. This is the first study demonstrating the potential threat of long-distance dispersal in a Cape lineage to the genetic integrity of local populations. Highlights • Hybridisation is considered to be rare within Cape lineages. • We detected hybrids between local Protea eximia and introduced P. susannae. • Hybrids were common and widespread in the Van Stadens Wildflower Reserve. • Translocations may result in unexpected hybridisation. • This may represent a risk to the genetic integrity of local populations and species. [ABSTRACT FROM AUTHOR]

Ecotone transitions between vegetation types are of interest for understanding regional diversity, ecological processes and biogeographical patterns. Ecotones are seldom represented on vector, line-based vegetation maps, which imply an instantaneous change from one vegetation type to another. We use supervised, probabilistic classification of remotely sensed (RS) imagery to investigate the location, width and character of ecotones between acid Sandstone and alkaline Limestone fynbos on the Agulhas plain at the southern tip of Africa, known for rapid speciation of plants and exceptional plant biodiversity at the global scale. The resultant probability map, together with the probability graphs developed for a few transects across the transition, are able to map and describe (1) sharp, narrow ecotones (under five meters); (2) moderate ecotones that have a distinct band of transition (over a few hundred meters); and (3) complex ecotones that include slow transitions, interdigitated boundaries and outliers. The latter class of transitions include portions where vegetation types change sharply over a few meters, but due to the interdigitated boundaries they are mapped over hundreds of meters to a kilometre at a landscape scale. In this study area, our findings suggest that the character of the Agulhas limestone-acid ecotone is probably more complex than often noted. Moderate transitions and broad mosaics are difficult to indicate in a vector vegetation map, whereas RS probabilistic classifications can output images indicating core areas, important for key species and biodiversity pattern, and transitional zones, important for ecosystem processes and perhaps plant evolution, which distinction is important for conservation planning. [ABSTRACT FROM AUTHOR]

Nineteen Phaeoacremonium species are currently known in South Africa. These have been reported from grapevines, fruit trees, fynbos twig litter and arthropods. In other countries some of these Phaeoacremonium species are also known from hosts such as European olive, quince and willow that commonly occur in the Western Cape Province of South Africa, where most South African records of Phaeoacremonium have been made. The aim of this study was to investigate the species diversity and host-range of Phaeoacremonium in the Western Cape Province of South Africa by characterising 156 isolates collected from 29 woody hosts. Phylogenetic analyses of combined actin and beta-tubulin datasets allowed for the identification of 31 species among the 156 isolates, including 13 new species and 3 known species that had not been recorded in South Africa previously. The new Phaeoacremonium species include P. album, P. aureum, P. bibendum, P. gamsii, P. geminum, P. junior, P. longicollarum, P. meliae, P. oleae, P. paululum, P. proliferatum, P. rosicola and P. spadicum. All previous records of P. alvesii in South Africa were re-identified as P. italicum, but both species were recovered during this survey. A total of 35 described Phaeoacremonium species are now known from South Africa, more than double the number reported from any other country. This high diversity reflects the high diversity of indigenous flora of the Cape Floral Region, a biodiversity hotspot mainly situated in the Western Cape Province. Paraphyly and incongruence between individual phylogenies of the actin and beta-tubulin regions complicated species delimitation in some cases indicating that additional phylogenetic markers should be investigated for use in Phaeoacremonium phylogenies to prevent misidentifications and the introduction of vague species boundaries. [ABSTRACT FROM AUTHOR]

Biological communities are increasingly faced with novel urban habitats and their response may depend on a combination of biological and habitat traits. The response of pollinator species to urban habitats are of particular importance because all species involved in the pollination mutualism may be affected. Nectarivorous bird communities worldwide show varying tolerances to urban areas, but studies from Africa are lacking. We investigated nectarivorous bird communities in a medium‐sized South African city and asked which biological and garden traits best predict the community assembly of specialist and opportunistic nectarivorous birds. Information was collected on garden traits and the frequency of nine nectarivorous bird species for 193 gardens by means of a questionnaire. Information on biological traits of birds was obtained from published literature. Habitat generalism and tree nesting were identified as the most important biological traits influencing bird occurrence in gardens. A greater diversity of indigenous bird‐pollinated plants and the presence of sugar water feeders increased the numbers of nectar specialist birds and species richness of nectarivorous birds. While bird baths increased the species richness of nectar specialist birds, opportunistic birds’ urban adjustment was further facilitated by large vegetated areas in gardens and limited by the distance to the nearest natural habitat. In conclusion, though some biological traits and dispersal barriers seem to limit urban adjustment, a combination of natural and artificial nectar resource provisioning could facilitate this adjustment. [ABSTRACT FROM AUTHOR]

Invasive alien plants (IAPs) are a major threat to biodiversity in South Africa's Cape Floristic Region (CFR). Activities like agricultural development, the establishment of forestry plantations and urbanization change environments and provide opportunities for IAPs to spread. We examine the factors that have contributed to plant invasions on a privately-owned farm in the CFR. The objectives of the study were: (1) to determine what land-use changes took place that could have influenced the spread of IAPs; and (2) to document the patterns of spread of IAPs. Aerial photographs from 1938, 1966, 1977, 1989 and 2004 were used to determine the types and rates of land-use change over time. Key land-use changes involved agriculture, commercial plantations, urban development and the spread of IAPs. The spatial analysis identified the main drivers of change. Agricultural development was the main land-use change driver and affected 40% of the study area by 1977. Areas occupied by IAPs increased with landuse change from 8% cover in 1938 to 40% in 2004, and then declined to 15% in 2013 following the initiation of control operations in 2004. The study illustrated a clear link between human activities, changes in land-use and the spread and proliferation of IAPs. [ABSTRACT FROM AUTHOR]

The outcomes of ecosystem restoration projects should be periodically monitored to inform subsequent adaptive management decisions. In 2012, a project was begun to remove both invasive alien plants and fish from the Rondegat River in South Africa. Although the initial post-intervention dynamics of aquatic fauna have been documented, the results of the simultaneous clearing of dense riparian stands of alien trees and shrubs have not been reported. We examined native riparian vegetation recovery over 3 years after alien plant clearing. We documented increased cover of native riparian shrubs, but a simultaneous increase of alien and native weedy grass cover. Secondary invasions, especially by grasses, can have strong effects on ecosystem dynamics and achieving the goals of restoration may therefore require additional active management. Our findings provide an initial baseline reference for future monitoring and adaptive management decisions. [ABSTRACT FROM AUTHOR]

The mega-diverse, Mediterranean-type fynbos biome may be vulnerable to future changes in climate and associated fire regimes, in particular to increasing summer-drought intensity and associated potential expansion of adjacent semi-arid vegetation types. Studying Holocene vegetation dynamics at the fynbos–succulent karoo boundary may provide insights into the resilience or sensitivity of fynbos to climate change. In this study, fossil pollen, non-pollen palynomorphs and charcoal data spanning ~5500 to −50 cal. yr BP were generated from an accelerator mass spectrometer (AMS) radiocarbon-dated sediment core extracted directly at the present-day fynbos–succulent karoo biome boundary at Groenkloof, a site in the Kamiesberg Mountains of Namaqualand, South Africa. Contrary to expectations, during the Mid-Holocene Altithermal from 5480 to 4025 cal. yr BP, fynbos and fire thrived through summer moisture subsidies associated with enhanced sub-tropical easterly flow. Subsequent cooling from 4025 to 2005 cal. yr BP resulted in enhanced summer drought and overall fynbos biome contraction, though woody fynbos shrubs persisted through physiological adaptations to drought. Desert succulents typical of the succulent karoo, such as those of Aizoaceae and Crassulaceae, failed to colonise the emergent niche space, resulting in dominance of an ambiguous grassy, asteraceous fynbos. More recent wetting associated with the ‘Little Ice Age’ Holocene temperature minima from 695 to 100 cal. yr BP prompted a resurgence in fynbos abundance, but frequent fire driven by pastoralists appears to have reduced the fynbos community’s functional diversity. Palaeoecological data from the Kamiesberg suggest that both climatic buffering of mountain refugia and high physiological resistance among certain fynbos taxa have contributed to the biome’s long-term resilience. Summer rainfall associated with the sub-tropical easterlies has been key in maintaining eastern fynbos refugia in past interglacial temperature maxima. The data also suggest that pre-historic land use and resulting fire-regime manipulations have resulted in the development of a taxonomically and functionally simplified alternative fynbos ecosystem state. [ABSTRACT FROM AUTHOR]

The Hottentot ButtonquailTurnix hottentotusis an endangered terrestrial turnicid and is endemic to the Fynbos biome, South Africa. Due to its secretive nature and apparent rarity almost nothing is known about the species, but its range has been subject to anthropogenic modification, invasion by alien plant species and is vulnerable to climate change. To model covariates associated with the presence of Hottentot Buttonquail we undertook flush surveys across the Fynbos biome, covering 275 km. Habitat variables at encounter sites were recorded in vegetation plots, as well as locations without encounters. There was a critical number of observers needed during a flush survey in order to account for buttonquail presence, with no encounters with less than five participants. After accounting for this, we found probability of encounters decreased with increasing time-since-fire. Probability of encounters were also negatively associated with increasing percentage grass and other vegetation cover. We also found no association between percentage cover of Restionaceae plants and encounter probability, considered previously to be the best indicator of Hottentot Buttonquail presence. This information will be of use to those interested in managing habitat for this species and should inform future conservation efforts. [ABSTRACT FROM PUBLISHER]

Organisms have evolved a diversity of life-history strategies to cope with variation in their environment. Persistence as adults and/or seeds across recruitment events allows species to dampen the effects of environmental fluctuations. The evolution of life cycles with overlapping generations should thus permit the colonization of environments with uncertain recruitment. We tested this hypothesis in Leucadendron (Proteaceae), a genus with high functional diversity native to fire-prone habitats in the South African fynbos. We analyzed the joint evolution of life-history traits (adult survival and seed-bank strategies) and ecological niches (climate and fire regime), using comparative methods and accounting for various sources of uncertainty. In the fynbos, species with canopy seed banks that are unable to survive fire as adults display nonoverlapping generations. In contrast, resprouters with an underground seed bank may be less threatened by extreme climatic events and fire intervals, given their iteroparity and long-lasting seed bank. Life cycles with nonoverlapping generations indeed jointly evolved with niches with less exposure to frost but not with those with less exposure to drought. Canopy seed banks jointly evolved with niches with more predictable fire return, compared to underground seed banks. The evolution of extraordinary functional diversity among fynbos plants thus reflects, at least in part, the diversity of both climates and fire regimes in this region. [ABSTRACT FROM AUTHOR]

Campos rupestres (on quartzite substrates) are an enigmatic habitat mosaic characterised by nutrient-poor (mainly phosphorus-deprived) soils and supporting grassland and scrub. They occur at high elevations of some mountain ranges of several eastern and central Brazilian states. Campos rupestres are known for high species diversity and remarkable plant endemism. This paper places the Brazilian campos rupestres into a global perspective and discusses questions if campos rupestres are a grassland or savanna, if they are zonal (to which zonobiome they should be classified) and if there are some habitat complexes (and vegetation) ecologically analogous to the campos rupestres found on other continents than South America. I suggest that the vegetation of campos rupestres is of azonal nature and a member of the global peinobiome (a type of pedobiome controlled by very low nutrient status). South African sourvelds and grassland scrub-grassy mosaics and similar habitats on sandstone plateaus of the Australian Top End were identified as the direct ecological analogues of the vegetation supported by the Brazilian quartzitic campos rupestres. [ABSTRACT FROM AUTHOR]

Vicariance and dispersal are two important processes shaping biodiversity patterns. The South African Cape Floristic Region (CFR) is known for its high biotic diversity and endemism. However, studies on the phylogeography of endemic invertebrates in this biodiversity hotspot are still scarce. Here, we present a phylogenetic study of the flightless grasshopper genus Betiscoides , which is endemic to the CFR and strongly associated with restio plants (Restionaceae). We hypothesized that the genus originated in the southwestern part of the CFR, that differentiation within the genus is mainly an effect of vicariance and that the three known species only represent a minor fraction of the real genetic diversity of the genus. We inferred the phylogeny based on sequences of three mitochondrial and two nuclear genes from 99 Betiscoides specimens collected across the CFR. Furthermore, we conducted a SDIVA analysis to detect distributions of ancestral nodes and the possible spatial origin of these lineages. Strong differentiation among genetic lineages was shown. The ancestor of this genus was most likely distributed in the southwestern CFR. Five major lineages were detected, three of which were ancestrally distributed in the southwestern CFR. The ancestors of the two other lineages were distributed in the northern and eastern margins of the CFR. A total of 24 divergent evolutionary lineages were found, reflecting the geographical isolation of restio-dominated fynbos habitats. Dispersal played a more prominent role than expected in differentiation of Betiscoides . While the five main lineages were separated during a first phase via dispersal, differentiation occurred later and on smaller spatial scale, predominantly driven by isolation in montane refugia (i.e. vicariance). Our study also suggests that flightless insect taxa likely show high levels of differentiation in biodiversity hotspots with their taxonomy often being incomplete. [ABSTRACT FROM AUTHOR]

Water affects distribution of many species, but climate change is set to change rainfall patterns and hence water availability. In South Africa, various global climate-change models suggest a drier future for the winter rainfall regions with implications for survival of plant and animal species of the fynbos region. Most birds offload heat by evaporative water loss, and this increases exponentially from 25°C. Birds need to replenish their water loss to cope particularly at high temperatures, especially species that have little preformed water in the diet. We documented bird species drinking at five natural water sources at a semi-arid fynbos site through time-lapse cameras to explore which birds are drinking when. We modelled the total numbers of birds observed drinking as a function of diet, mass and relative abundance and found that species classified as granivores were predicted to drink most frequently, with the more common species most frequently recorded. A phylogenetically controlled trait-based logistic regression indicated abundance as the best predictor of observation at the water sources. Daily drinking rates at the species level for the ten most frequently observed species were generally best explained by daily temperature, with higher drinking rates on hotter days. However, daily drinking patterns were poorly explained by diurnal temperature trends at the hourly level, and we were unable to document sufficient predators to comment on the influence of predator avoidance or other heat mitigation strategies. Finally, we discuss the implications of our observations for the set of fynbos endemic passerines. [ABSTRACT FROM AUTHOR]

Alien plant invasions are a major threat to biodiversity and ecosystem functioning in South Africa’s Cape Floristic Region (CFR). Large-scale government-funded management initiatives are underway to reduce the extent of invasions in this region. Among the many challenges are the huge spatial extent of the invasions and difficulties in coordinating management efforts across large areas of invaded land in private ownership. Very little information is available on the success of privately-funded alien plant control initiatives. This study investigated the effectiveness of one large project in reducing alien plant cover, the challenges faced and the costs associated with long-term clearing operations on privately-owned land in the CFR. Results for the study area (Vergelegen) show that the cover of dense invasive plant stands declined by 70% over 10 years since management operations began, but that operations cost 3.6 times more than was originally estimated (ZAR 43.6 vs 12.19 million, respectively). The challenges associated with managing invasive alien plants (IAPs) on private land are very similar to those faced on state-owned land, with the efficiency of management being constrained by multiple interacting environmental and socio-economic factors. However some success in managing IAPs can be achieved by adhering to basic principles, including careful planning with clear achievable goals in mind, a commitment to stable long-term funding and regular monitoring. Most private land owners cannot afford the substantial investment of resources that would be required to clear large stands of IAPs and to ensure that cleared areas are maintained to prevent re-invasion, and finding ways to fund this remains a challenge. [ABSTRACT FROM AUTHOR]

Pine plantations and pine invasions have numerous impacts on native ecosystems in the Fynbos biome of South Africa. The severity of these impacts greatly determines the extent of potential ecosystem recovery after the pines are felled. The recovery potential of fynbos after felling of pine plantations of varying longevity and the subsequent application of ecological burns was investigated in the Helderberg Nature Reserve, Western Cape Province, South Africa. Above-ground vegetation, soil seed bank and abiotic variables were sampled across three treatments (reference fynbos and sites that had been under pines for 30 and 50 years respectively) using 1 m 2 quadrats placed along 50 m line transects. The soil seed bank samples were smoke treated and then monitored in a greenhouse to determine the soil seed bank species and growth form composition. Areas previously under 30 year old pine plantations had high native species and growth form density (number of species/growth forms per unit area) and similar plant density (number of individuals per unit area) to the reference fynbos areas. Conversely, areas previously under 50 year old pine plantations had significantly lower native species and growth form density and plant density than the reference fynbos and were dominated by alien species. In addition, areas previously under 50 year old pine plantations had lower species diversity than the reference fynbos areas and areas previously under 30 year old pine plantations which were found to be similar to one another. Felled pine plantations were shown to minimally impact on soil abiotic variables, with only soil temperature and pH showing significant differences. Therefore, areas previously under 30 year old pine plantations have higher recovery potential following pine removal than 50 year old plantations, owing to the depleted native soil seed bank in the latter. Consequently, active restoration may be needed to re-introduce the missing long-lived growth forms and to prevent soil erosion. Pine plantation and invasion management in the Fynbos biome should aim to fell pines before the native seed bank is depleted to maintain the recovery potential of fynbos and prevent the need for active restoration. [ABSTRACT FROM AUTHOR]

Stress, as a temporary defense mechanism against specific stimuli, can place a bird in a state in which growth rates and resistance to diseases are diminished. The Cape Sugarbird Promerops cafer is an endemic specialist of the Cape Floristic Region (CFR) of South Africa that may be threatened by urbanization and climate change. Ecological stress due to urbanization and climate may result in disease and morphological abnormalities. We investigated the correlation between urbanization and climate and four ecological stress indicators (tarsal disease, fluctuating asymmetry, body condition and feather fault bars) in 1375 Cape Sugarbirds from 14 sites across the CFR. Sugarbirds at sites with warmer climates had a higher incidence of tarsal disease and fault bars. Birds closer to urban settlements had higher levels of fluctuating asymmetry and fault bars in feathers. There were no clear correlations among stress indicators. Cape Sugarbirds are subject to multiple stressors, and adequate monitoring of population health will require assessment of multiple rather than single stress responses. [ABSTRACT FROM AUTHOR]

A survey of vascular plant species occurring in various wetland habitats in South Africa has been generated by supplementing the species list from a vegetation survey with a herbarium checklist and this list of wetland species is compared with the overall flora of South Africa. About 18.8% of all the South African species occur in wetlands and about 4.5% of all species are obligate wetland species, in the sense that they will not be found outside of the wetland environment. These fractions are compared with the fractions calculated per family and this indicates which families are over- or underrepresented in the South Africa wetland flora. Most of the families that are well represented in wetlands are in the monocots and particularly in the Poales, but wetlands in the Fynbos Biome are much more phylogenetically diverse. There are four main wetland assemblages that can be defined by their family composition and that are characteristic of specific wetland environments. These can generally be described as the environments that are permanently submerged, the environments that are permanently to intermittently inundated, the environments of inland saline pans and environments on extremely nutrient-poor substrates consisting of coastal sands, quartzites or peat. [ABSTRACT FROM AUTHOR]

Ambiguous species delimitations and nomenclature are a major impediment for users of biodiversity information. This is more pronounced in plant lineages that have experienced recent and rapid diversification or where there is a tendency to lump many species under a general name. The papilionoid genus Psoralea L. is a young lineage (Pliocene, ca. 75 species) which has diversified rapidly within the South African fynbos biome and adjacent habitats. All species bearing 5–19 foliolate leaves were previously often lumped within the polymorphic species Psoralea pinnata , resulting in an unwieldy complex of at least 28 taxa, of which only eleven species are formally named. In this study we analyzed live specimens and populations in the field and herbarium collections, capturing their morphological and geographic diversity, for species delimitation. The results support the recognition of 25 distinct species, of which 14 are described here as new: P. azuroides ; P. brilliantissima ; P. elegans ; P. floccosa ; P. imminens ; P. intonsa ; P. ivumba ; P. kougaensis ; P. montana ; P. muirii ; P. rhizotoma ; P. semota ; P. sordida ; and P. suaveolens . The taxon P. pinnata var. latifolia Harv. is raised to species rank, as P. latifolia comb. nov. The name P. pinnata sensu stricto is restricted here to a taxon with 5–9-leaflets extending from the Cape Peninsula to the Kogelberg mountains. We provide a key for the identification of all 25 species along with full descriptions, distribution maps and notes on their conservation status. [ABSTRACT FROM AUTHOR]

Seed mortality represents a substantial cost for plants and can have a large effect on plant reproductive fitness. Here we report evidence for pre-dispersal seed mortality by a novel mechanism: culm felling in female nut-seeded restios by rodents. We noted strong female-specific culm felling in the nut-fruited Cannomois congesta Mast. (Restionaceae) from the South Western Cape, South Africa. Camera-trap analysis showed that this culm felling is carried out by the striped mouse, Rhabdomys pumilio Spar. (Muridae) and is primarily aimed at obtaining ripe seeds held at the tips of female culms rather than eating the culm. All seeds acquired by R. pumilio were found to be consumed. We recorded a mean loss of 81% culms/seeds in affected female C. congesta plants in contrast to very few culm losses from males. This highly selective rodent behaviour is presumably due to detectable differences in the nutritional reward associated with terminal male/female inflorescences (large nut-like seeds vs. pollen). Pre-dispersal seed predation through culm felling could significantly reduce the fecundity of ant-dispersed restios such as C. congesta because fewer seeds manage to fall to ground where mutualistic ground foraging ants compete with rodents for seeds. Culm losses through felling could also have physiological and nutritional implications. Future research should explore the generality of this phenomenon amongst the Restionaceae, and quantify the associated physiological and reproductive costs. [ABSTRACT FROM AUTHOR]

Conservation biologists and ecologists often make use of models to identify important biotic and abiotic factors that constrain species distributions for conservation decisions to be taken. In line with such practices, we developed species distribution models for four localized, Cape Floristic Region (CFR) endemic, flightless, congeneric Euloryma grasshopper species. We chose this group as use of these models has been little explored for narrow range endemics with specific traits. Euloryma larsenorum and E. lapollai are associated with fynbos only, while E. umoja and E. ottei are both associated with fynbos and vineyards. We used the Maximum Entropy algorithm, which showed that vegetation type and soil characteristics were the most important environmental factors affecting local distribution of Euloryma species in the CFR. The models also showed that Euloryma species have a very narrow habitat suitability range in the CFR. We also showed that there are no significant differences in the distribution of species associated with fynbos only as well as those associated with both fynbos and vineyards. E. larsenorum and E lapollai are likely to be the most affected species in the event of further habitat transformation from fynbos to agricultural production. This is not likely to be the case for E. umoja and E. ottei which can tolerate agriculture environment, although they might survive both sets of environments in accordance with their life history traits. [ABSTRACT FROM AUTHOR]

Background: In many countries around the world, the most damaging invasive plant species are grasses. However, the status of grass invasions in South Africa has not been documented recently. Objectives: To update Sue Milton's 2004 review of grasses as invasive alien plants in South Africa, provide the first detailed species level inventory of alien grasses in South Africa and assess the invasion dynamics and management of the group. Method: We compiled the most comprehensive inventory of alien grasses in South Africa to date using recorded occurrences of alien grasses in the country from various literature and database sources. Using historical literature, we reviewed past efforts to introduce alien grasses into South Africa. We sourced information on the origins, uses, distributions and minimum residence times to investigate pathways and patterns of spatial extent. We identified alien grasses in South Africa that are having environmental and economic impacts and determined whether management options have been identified, and legislation created, for these species. Results: There are at least 256 alien grass species in the country, 37 of which have become invasive. Alien grass species richness increased most dramatically from the late 1800s to about 1940. Alien grass species that are not naturalised or invasive have much shorter residence times than those that have naturalised or become invasive. Most grasses were probably introduced for forage purposes, and a large number of alien grass species were trialled at pasture research stations. A large number of alien grass species in South Africa are of Eurasian origin, although more recent introductions include species from elsewhere in Africa and from Australasia. Alien grasses are most prevalent in the south-west of the country, and the Fynbos Biome has the most alien grasses and the most widespread species. We identified 11 species that have recorded environmental and economic impacts in the country. Few alien grasses have prescribed or researched management techniques. Moreover, current legislation neither adequately covers invasive species nor reflects the impacts and geographical extent of these species. Conclusion: South Africa has few invasive grass species, but there is much uncertainty regarding the identity, numbers of species, distributions, abundances and impacts of alien grasses. Although introductions of alien grasses have declined in recent decades, South Africa has a potentially large invasion debt. This highlights the need for continued monitoring and much greater investment in alien grass management, research and legislation. [ABSTRACT FROM AUTHOR]

Prolonged periods of extreme heat or drought in the first year after fire affect the resilience and diversity of fire-dependent ecosystems by inhibiting seed germination or increasing mortality of seedlings and resprouting individuals. This interaction between weather and fire is of growing concern as climate changes, particularly in systems subject to stand-replacing crown fires, such as most Mediterranean-type ecosystems. We examined the longest running set of permanent vegetation plots in the Fynbos of South Africa (44 y), finding a significant decline in the diversity of plots driven by increasingly severe postfire summer weather events (number of consecutive days with high temperatures and no rain) and legacy effects of historical woody alien plant densities 30 y after clearing. Species that resprout after fire and/or have graminoid or herb growth forms were particularly affected by postfire weather, whereas all species were sensitive to invasive plants. Observed differences in the response of functional types to extreme postfire weather could drive major shifts in ecosystem structure and function such as altered fire behavior, hydrology, and carbon storage. An estimated 0.5 °C increase in maximum temperature tolerance of the species sets unique to each survey further suggests selection for species adapted to hotter conditions. Taken together, our results show climate change impacts on biodiversity in the hyperdiverse Cape Floristic Region and demonstrate an important interaction between extreme weather and disturbance by fire that may make flammable ecosystems particularly sensitive to climate change. [ABSTRACT FROM AUTHOR]

To aid prescribed burn decision making in Table Mountain National Park, in South Africa a priority ranking system was tested. Historically a wildfire suppression strategy was adopted due to wildfires threatening urban areas close to the park, with few prescribed burns conducted. A large percentage of vegetation across the park exceeded the ecological threshold of 15 years. We held a multidisciplinary workshop, to prioritize areas for prescribed burning. Fire Management Blocks were mapped and assessed using the following seven categories: (1) ecological, (2) management, (3) tourism, (4) infrastructure, (5) invasive alien vegetation, (6) wildland-urban interface and (7) heritage. A priority ranking system was used to score each block. The oldest or most threatened vegetation types were not necessarily the top priority blocks. Selected blocks were burnt and burning fewer large blocks proved more effective economically, ecologically and practically due to the limited burning days permitted. The prioritization process was efficient as it could be updated annually following prescribed burns and wildfire incidents. Integration of prescribed burn planning and wildfire suppression strategies resulted in a reduction in operational costs. We recommend protected areas make use of a priority ranking system developed with expert knowledge and stakeholder engagement to determine objective prescribed burn plans. [ABSTRACT FROM AUTHOR]

Protea -associated fungi are dispersed between flower heads by mites, beetles and possibly birds. For the ophiostomatoid fungus, Knoxdaviesia proteae , these vectors offer regular dispersal between distant floral hosts. Unlike K. proteae , Knoxdaviesia capensis occupies multiple Protea host species. In this study, we aimed to determine whether the generalist K. capensis shares the long-distance dispersal pattern with specialist K. proteae and whether it moves freely between different host species. We evaluated the genetic structure of K. capensis from five populations of a wide-spread host and between sympatric hosts. Twelve K. capensis -specific microsatellite markers were developed and applied to 90 individuals. K. capensis showed high genetic diversity and almost maximal genotypic diversity. All populations were poorly differentiated, indicating the presence of long-distance dispersal. No differentiation could be detected between sympatric host populations, suggesting free dispersal between different hosts. This implies that the beetle and bird vectors that pollinate Protea species show the same non-specific movement. [ABSTRACT FROM AUTHOR]

Studying the diet of wild animals is central for understanding their flexibility in food requirements. The Black HarrierCircus maurusis an endangered raptor in South Africa and Namibia. To date, information about the diet of the species is insufficient for a comprehensive understanding of its ecology. We studied the diet composition of breeding Black Harriers using c. 1 000 pellets (>1 700 identified prey) collected at nest sites in two geographical regions (coastal vs inland) over 10 breeding seasons (2006–2015). We show the importance of small mammals in Black Harrier diet (64.4% and 78.2% of prey and consumed biomass, respectively), with the four-striped mouseRhabdomys pumiliobeing a main trophic resource. We also reveal the importance of birds and reptiles as alternative prey, particularly in inland regions, and show inter-annual variations in diet in both regions. Our study confirms that this species can be considered a small mammal specialist. Specialist predators are more vulnerable than generalist ones and diet specialisation has been linked with a poorer conservation status in other species. Our results thus have implications for the conservation of this species in southern Africa. These are highlighted for the long-term sustainability of this threatened endemic species. [ABSTRACT FROM AUTHOR]

Invertebrates are essential for ecosystem functioning and have received much attention in biodiversity, conservation and ecological studies. Numerous collection techniques for assessing arthropod diversity exist, but there is little understanding of the consequences of choice of any particular method. This information is essential for project planning and for the interpretation of results. Here we assess sweep netting and suction sampling, two widely used methods for sampling foliage arthropods, and compare them in terms of their efficacy and effort in surveying arthropod biodiversity. Arthropods were collected in paired transects in shrubby fynbos vegetation in the Cape Floristic Region, a biodiversity hotspot. Overall, the vacuum sampling collected significantly more species and individuals than sweep netting, although this was taxon specific. Use of the vacuum sampler significantly increased the time spent in the field per transect and it also collected significantly more dead plant biomass than the sweep net, thus requires a longer period to sort samples afterwards. Sweep netting caused significantly more damage to plants, an important consideration when working in sensitive ecosystems. Assemblage composition of arthropods collected by the two methods were significantly different with only about half of all arthropod species collected shared between the two methods. Our results show that overall, the vacuum sampler outperformed the sweep net in terms of arthropod species richness and abundance and minimising damage to vegetation, but that it takes considerably longer to collect the relevant data. When more representative biodiversity surveying is needed, the use of both techniques is encouraged. [ABSTRACT FROM AUTHOR]

To date, the biological soil crusts (BSCs) of southern Africa are thought to be dominated mainly by cyanobacteria, with the exception of the lichen fields of the Namib Desert. Because soil microorganisms can physically modify, maintain or create habitat for other organisms – including soil biota and plants – they have been considered ecosystem engineers. Therefore, the presence of BSCs may be a good indicator of ecosystem resilience. Although BSCs are found throughout the world, recent work has suggested that the absence of BSCs in the fynbos of South Africa may be as a result of the inherent acidity of soils. We surveyed one area within the fynbos biome for the presence of BSCs and determined the relative cover of vegetation and different crust types. We found a widespread presence (up to 80% of surface soil) of BSC communities in fynbos soils. We conclude that soil acidity may not be a constraining factor in the development of BSCs in fynbos soils and that previous reports on the absence of BSCs in fynbos soils may have been based on insufficient field observations. We encourage future studies in this region in order to determine the currently unexplored spatial distribution of soil microbial communities and the taxonomic composition of microorganisms in fynbos soils.

Pollen grains of Rhigiophyllum squarrosum Hochst., Siphocodon spartioides Turcz. and S. debilis Schltr., are flattened and triangular with pores at the angles. This morphology is radically different from known pollen of the Campanulaceae s.sfr:: the Campanulaceae are treated here as a family separate from the Lobeliaceae, Cyphiaceae, Nemacladaceae, Pentaphragmataceae and Sphenocleaceae (Lammers 1992). As traditionally conceived, the Campanulaceae is very heterogeneous and, in many classifications, these families were treated as subfamilies of a much-enlarged Campanulaceae. The consistently different floral morphology, biochemistry and pollen structure of the Lobeliaceae favours the recognition of this predominantly tropical group as a separate family. The pollen grains of these species are described in comparison with other members of the Campanulaceae. Based on surface characteristics of their pollen grains, we conclude that they represent an early offshoot o f the wahlenbergioid line­age in southern Africa. We suggest that this unique pollen may also be the result of a highly selective regime in the fynbos, associated with specialized pollinators, and base-poor soils, in addition to possible adaptations for ant dispersal and fire. Rhigiophyllum Hochst. and Siphocodon Turcz. are also unique in having free carpel-like structures within the ovary. These shrink to form seed pockets around the seeds and disperse as units when the capsule matures. Data from molecular studies support the contention that these taxa form a sister group to all other wahlenbergioids and that this should be formally recognized in a classification system. We treat Rhigiophyllum and Siphocodon within the Campanulaceae: Wahlenbergioideae, as a separate tribe, the Rhigiophylleae tribus nov., the species of which are distinguishable from other wahlenbergioids by unique angulaperturatc pollen, epipetalous stamens, free carpel-like structures and seed pockets.

The private Grootbos Nature Reserve is located at the Western edge of the Agulhas Plain in the Cape Floristic Region of South Africa, an area characterized by high habitat and floristic diversity. The Reserve is covered in near-natural fynbos shrublands with a few patches of forest and wetland. The main objective of this study was to classify the vegetation into discrete units and relate them to the prevailing environmental conditions. The vegetation was analysed by numerical means (TWINSPAN, DC A, CCA) and mapped on GIS. At the vegetation type level. Forest & Thicket and Fynbos formed distinctive clusters, whereas the wetland releves were intermixed, but without relationships to one of these units. Fire incidence served as the major determinant of the forest-fynbos boundary. The Forest & Thicket grouping was separated into Thicket (as transitional to fynbos), Afromontane Forest and Milkwood Scrub Forest. Two broad complexes were distinguished within the Fynbos grouping, the Alkaline Sand Fynbos Complex corresponding to Coastal Fynbos. and the Acid Sand Fynbos Complex corresponding to Mountain Fynbos. They discriminated along gradients of pH. soil depth and rock cover. The complexes were further subdivided into formations by using one or a few subjectively chosen dominant species as indicators. The transitions between these formations were rather continuous than discrete. The vegetation type and complex levels correspond well to existing fynbos-wide classifications. Comparing the formations to the results of other vegetation studies is problematic even on the scale of the Agulhas Plain, due to the high regional plant diversity in the Fynbos Biome.

This paper provides an assessment of fire regimes in the Table Mountain National Park over the past four decades. We compiled a GIS database of all fires between 1970 and 2007 and analysed the fire regime in terms of the frequency, season and size of fires and the relationship between fire occurrence and fire weather. Most fires (90.5% of area burnt) occurred in summer and autumn, the ecologically acceptable season for fires. However, mean fire return intervals declined by 18.1 years, from 31.6 to 13.5 years, between the first and last decades of the record respectively. The area subjected to short (≤ six years) intervals between fires covered > 16% of the park in the last two decades of the record, compared to ~ 4% in the first two decades. A relatively small number of large fires dominated in terms of area burnt. Of the 373 fires recorded, 40 fires > 300 ha burnt 75% of the area, while 216 fires < 25 ha burnt 3.4% of the area. Fires occurred under a wide range of weather conditions, but large fires were restricted to periods of high fire danger. Prescribed burning was a relatively unimportant cause of fires, and most (> 85%) of the area burnt in wildfires. Areas subjected to short fire return intervals should be considered for management interventions. These could include the re-establishment of extirpated fire-sensitive species, the clearing of invasive alien plants and increased precautions for the prevention or rapid suppression of future accidental fires.