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Legumes in the Fynbos vegetation of the Western Cape of South Africa have emerged as candidates for domestication, particularly for their adaptation to acidic and infertile soils. However, South African rhizobia have been shown to be very diverse and unique, and a detailed understanding of them is essential to success in forage breeding programs that seek to exploit these "new" legumes. Symbionts of legumes in South Africa that belong to traditional rhizobial genera have been shown to have a unique origin for their symbiotic loci in comparison to members sampled from other regions of the world. Some of the legume tribes in the Fynbos have also been shown to associate predominantly with unique species in the Betaproteobacterial genus Paraburkholderia. The rhizobial members of this genus have two main centres of diversity, of which South Africa is one. In this centre, the legume hosts are principally from the Papilionoideae subfamily while hosts from the mimosoid clade (now in the Caesalpinioideae) are abundant in the South American centre. Not only do these rhizobia differ in terms of host, but their symbiotic loci also show separate origins. The dominance and uniqueness of the Paraburkholderia symbionts, in the context of indigenous South African legumes, makes understanding the history and factors that affect the distribution of this genus essential if successful adaptation and effective nodulation of these legumes in Agriculture are to be achieved globally. [ABSTRACT FROM AUTHOR]

Background: Concern has been expressed about the effectiveness of invasive alien plant (IAP) control operations carried out by Working for Water (WfW). South African legislation now also requires reporting on the effectiveness of IAP management interventions. Objectives: We assessed the effectiveness of IAP management practices in a large fynbos protected area, the Garden Route National Park, South Africa. Methods: We undertook field surveys of pre-clearing IAP composition and the quality of treatments applied by WfW during 2012-2015 in 103 management units, covering 4280 ha. We furthermore assessed WfW data for evidence of change in IAP cover after successive treatments, and adherence to industry norms. Results: Despite the development of detailed management plans, implementation was poorly aligned with plans. The quality of many treatments was inadequate, with work done to standard in only 23% of the assessed area. Problems encountered included (1) a complete absence of treatment application despite the payment of contractors (33% of assessed area); (2) treatments not being comprehensive in that select areas (38%), IAP species (11%) or age classes (8%) were untreated; (3) wrong choice of treatment method (9%); and (4) treatments not applied to standard (7%). Accordingly, successive follow-up treatments largely did not reduce the cover of IAPs. Inaccurate (or lack of) infield estimation of IAP cover prior to contract generation resulted in erroneous estimation of effort required and expenditure disparate with WfW norms. Conclusions: We advocate rigorous, compulsory, infield assessment of IAP cover prior to contract allocation and assessment of the quality of treatments applied prior to contractors' payment. This should improve the efficiency of control operations and enable tracking of both the state of invasions and effectiveness of management. [ABSTRACT FROM AUTHOR]

Many plant–animal interactions can be challenging to directly observe, due to species being small, cryptic and/or nocturnal. Previous research on seed predation and dispersal by rodents in the Fynbos Biome of South Africa has relied on indirect evidence, as methods for directly monitoring rodent–seed interactions were not available. The aims of the study were to determine which resident small mammals scatter-hoard nuts and the geographic, seasonal and taxonomic extent of scatter-hoarding in the Fynbos Biome. We used camera traps focused on seed stations at eight sites in the Fynbos Biome to determine the responses of small mammals to tagged nut-like fruits (nuts) of seven endemic plant species belonging to the Proteaceae (n= 3), Rosaceae (n= 2), Restionaceae (n= 1) and Cupressaceae (n= 1), as well as commercial sunflower seeds. We foundAcomys subspinosusandGerbilliscus paebascatter-hoarded nuts, which they typically carried and buried individually.Rhabdomys pumilioandMicaelamys namaquensisonly consumed nuts.Leucadendron pubescensandL. loranthifoliumare added to the list of known plant species that are scatter-hoarded by rodents. Nuts ofCliffortia cuneataandC. phillipsii, and the critically endangeredWiddringtonia cedarbergensis, were consumed but not dispersed by small mammals, whereas nuts ofCeratocaryum argenteumwere neither consumed nor scatter-hoarded by rodents (within its native range).Gerbilliscus paebaandA. subspinosusscatter-hoarded nuts aseasonally, outside of seed-fall periods. Scatter-hoarding was widespread throughout the Fynbos Biome, although it was highly localised across and within sampled sites. The absence of scatter-hoarding rodents at sites with rodent-dispersed plants remains an important aspect for future investigation. [ABSTRACT FROM AUTHOR]

Relationships between true population densities and reporting indices from atlas data are important for the calculation of population sizes, though these relationships are remarkably little-known and likely confounded by issues of detection. We examine issues of detection for a single-observer point-count survey across the Fynbos biome in South Africa. We created an index of relative abundance comparable to atlas reporting rate and calculated detection coefficients for each species. We explore various models that explain relative abundance as a function of detection covariates, e.g. mass, colour, group size, vocal behaviour and density. Density was consistently included across models and the best predictor when used alone in a validation exercise. We then calculated mean reporting rates for the citizen science South African Bird Atlas Project2 (SABAP2). A model of species’ reporting rates as determined by density for this set of birds suggested the correlation between atlas reporting rates and density estimates was weak, with species capable of using modified habitats exhibiting higher reporting rates than expected from the density estimates. There was a positive correlation between bird density and reporting rates corrected for by species mass. We used this relationship to calculate densities for the Fynbos bird species and compare results to published data. [ABSTRACT FROM AUTHOR]

The Greater Cape Floristic Region (GCFR) in South Africa has been extensively investigated for its phenomenal angiosperm diversity. A key emergent pattern is the occurrence of older plant lineages in the southern Fynbos biome and younger lineages in the northern Succulent Karoo biome. We know practically nothing, however, about the evolutionary history of the animals that pollinate this often highly-specialized flora. In this study, we explore the evolutionary history of an important GCFR fly pollinator, Megapalpus capensis , and ask whether it exhibits broadly congruent genetic structuring and timing of diversification to flowering plants within these biomes. We find that the oldest M. capensis lineages originated in Fynbos during the Miocene, while younger Succulent Karoo lineages diverged in the Pliocene and correspond to the proposed age of this recent biome. A strong signature of population expansion is also recovered for flies in this arid biome, consistent with recent colonization. Our first investigation into the evolutionary history of GCFR pollinators thus supports a recent origin of the SK biome, as inferred from angiosperm phylogenies, and suggests that plants and pollinators may have co-diverged within this remarkable area. [ABSTRACT FROM AUTHOR]

Although fire is a natural form of disturbance in many ecosystems, the frequency of fires is increasing due to human activities. Hence, understanding the impacts of fire on biodiversity and ecosystem functioning has become increasingly important. In this study we investigated the effects of a large-scale fire on an important soil-dwelling group, springtails (Collembola), one year before and for three consecutive years after a fire in the fire-prone fynbos ecosystem in South Africa. In particular, we investigate the resistance of the springtail assemblages (i.e. their ability to remain relatively unchanged in the face of a disturbance), and their resilience (i.e. ability to return to a pre-disturbance state). To do this we sampled two sites with contrasting vegetation ( Erica and Protea ) and used three different standardized litter types in litterbag traps. A total of 35 springtail species from 31 genera and 14 families was found. The springtail assemblages in this fynbos system showed slightly more resistance to fire than resilience after the fire event, though substantial variation was found among vegetation types. Mean species richness and abundance per litterbag varied among the Protea and Erica sites, with resistant species being dominant in the Erica site, while species that showed an increase after the fire were dominant in the Protea site. Differences were also found between life forms: atmobiotic (free-living in vegetation) and epiedaphic (surface dwelling) species showed a significant decline in mean species richness directly after the fire in the Erica site. Euedaphic (soil-dwelling) species richness remained unchanged post-fire in the Erica site, while actually slightly increasing after the fire in the Protea site. Although the fynbos springtail assemblages had not fully recovered to pre-fire abundance after three years, many species appear to be resistant to or recover rapidly after fires, at least as ascertained over the relatively short (four years) duration of the study. It is likely that this response is influenced by the presence of suitable refugia within sites and by species-specific traits. Given changing fire regimes and the increasing frequency of fires due to human disturbances, the system will likely become more dominated by resistant springtail species preferring nutrient rich circumstances and easily decomposed litters. [ABSTRACT FROM AUTHOR]

Aims In Mediterranean-type ecosystem, the Cape Fynbos, legumes may be able to switch between soil N and atmospheric N2 sources during growth to adjust the carbon costs of N acquisition. This study investigated the utilization of different inorganic N sources by Virgilia divaricata, a native legume from the Mediterranean-type ecosystem of the Cape Floristic Region. Methods Plants were cultivated in sterile quartz sand, supplied with 25% strength Long Ashton nutrient solution, modified to contain 500 μM Phosphate. At the phosphate level (500 μM), plants were treated with 500 μM NH4NO3 (treatment named N), or grown in N-free nutrient solution and inoculated with effective Burkholderia sp. (Bact.) or treated with combined N sources (500 μM NH4NO3) and inoculated with effective Burkholderia sp. (N+Bact.). Important Findings The application of NH4NO3 to the legumes resulted in a greater increase in plant dry matter. Carbon construction costs were higher in plants that were supplied with mineral and symbiotic N sources. Maximum photosynthetic rates per leaf area was maintained, irrespective of the N sources. Although the plant roots were nodulated, the plant dependence on N2 fixation decreased with addition of N. Roots and nodules of the plants solely reliant on N2 fixation showed an increase in glutamine content. These results show that V. divaricata is highly adapted for growth at the forest margin. Fynbos and possibly anthropic soils by utilizing both atmospheric and soil N sources. [ABSTRACT FROM AUTHOR]

There has been recent debate about the extent to which human disturbance of the landscape affects wetland invertebrates given that the organisms are already adapted to high levels of natural disturbance. Using repeated sampling of a set of 12 temporary wetlands occurring in a differentially transformed Sand fynbos landscape in Cape Town (South Africa), we investigated patterns of macroinvertebrate and microcrustacean assemblage composition, richness and diversity in relation to a physico-chemical gradient resulting from variable habitat loss in the adjacent landscape. Both macroinvertebrates and microcrustaceans showed clear gradational changes in assemblage composition in relation to the surrounding cover of indigenous vegetation (as a proxy for habitat loss). Although the composition of assemblages appeared to be affected by this gradient of habitat transformation, no relationships were detected using various measures of taxon richness and diversity. At the small spatial scale for which patterns are analysed, the influence of natural variation on invertebrate assemblages appears to have been overridden by that resulting from habitat transformation in the adjacent landscape. Depression wetlands embedded in Sand fynbos habitat appear to be unique in terms of their physico-chemistry (acidic and rich in humic substances) and the invertebrate assemblages they support. [ABSTRACT FROM AUTHOR]

Climate change constitutes a potential threat to montane biodiversity, particularly in low-altitude, tropical mountains; however, few data exist for the Afromontane taxa. In South Africa, the temperate grassland and fynbos biomes are mostly associated with the Great Escarpment and the high-lying central plateau. Varying contractions of the grassland and fynbos biomes are predicted under different climate scenarios by 2050. Animal taxa adapted to these biomes should suffer similar range declines and can be used to independently test the vegetation models. We constructed MaxEnt models from 271 unique locality records for three species of montane and submontane vlei rats that are closely associated with grassland (Otomys auratus, Wroughton 1906), mesic savanna (Otomys angoniensis, Wroughton 1906), and fynbos (Otomys irroratus, Brants 1827) biomes in South Africa. Projected range shifts under the A2 emission scenario of the Intergovernmental Panel on Climate Change showed increases (O. angoniensis) and decreases (O. auratus) that closely mirrored those expected for the savanna and grassland biomes, respectively. Comparison of historical (from 90 years ago) and current occurrence data from a zone of sympatry in the tropical Soutpansberg Mountains (at 1250 m asl) showed complete replacement of the grassland-adapted rodent species (O. auratus) by the savanna-adapted species (O. angoniensis) due to historically documented changes from a grassland-dominated to thicket-dominated landscape. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore the effects of anthropogenic climate change on the dwarf succulent genus Conophytum (Aizoaceae) within areas recognised for their floral biodiversity, namely the Succulent Karoo, Fynbos, Desert and Nama Karoo biomes of South Africa and Namibia. Niche-based modelling was used to identify the key climatic and geological variables influencing the distribution of members of the genus Conophytum . The distribution of the genus is primarily controlled by a small number of environmental variables, notably winter and summer rainfall levels, together with geology. Assuming a zero-dispersal model, the predicted effect of both the A1B and A2 climatic emission scenarios was a severe contraction in the area satisfying the bioclimatic envelope for the genus coupled with significant range dislocation. Reductions of >90% in suitable habitat for 10 of the 16 taxonomic Sections that comprise the genus and represent >80% of taxa under the A2 scenario are predicted. Under A1B the projected effects are ameliorated, but reductions of >50% of habitat can be seen in a majority of Sections. Significant projected reductions in the habitable bioclimatic envelope are very likely to increase risk of extinction of ∼80% of taxa even under a partly mitigated emissions scenario. [ABSTRACT FROM AUTHOR]

This paper presents the first continuous pollen record from the southern Namib Desert spanning the last 50,000 years. Obtained from rock hyrax middens found near the town of Pella, South Africa, these data are used to reconstruct vegetation change and quantitative estimates of temperature and aridity. Results indicate that the last glacial period was characterised by increased water availability at the site relative to the Holocene. Changes in temperature and potential evapotranspiration appear to have played a significant role in determining the hydrologic balance. The record can be considered in two sections: 1) the last glacial period, when low temperatures favoured the development of more mesic Nama-Karoo vegetation at the site, with periods of increased humidity concurrent with increased coastal upwelling, both responding to lower global/regional temperatures; and 2) the Holocene, during which time high temperatures and potential evapotranspiration resulted in increased aridity and an expansion of the Desert Biome. During this latter period, increases in upwelling intensity created drier conditions at the site. Considered in the context of discussions of forcing mechanisms of regional climate change and environmental dynamics, the results from Pella stand in clear contrast with many inferences of terrestrial environmental change derived from regional marine records. Observations of a strong precessional signal and interpretations of increased humidity during phases of high local summer insolation in the marine records are not consistent with the data from Pella. Similarly, while high percentages of Restionaceae pollen has been observed in marine sediments during the last glacial period, they do not exceed 1% of the assemblage from Pella, indicating that no significant expansion of the Fynbos Biome has occurred during the last 50,000 years. These findings pose interesting questions regarding the nature of environmental change in southwestern Africa, and the significance of the diverse records that have been obtained from the region. [ABSTRACT FROM AUTHOR]

Erica dominate the fynbos ecosystem, which is characterized by acidic soils that are rich in organic matter. The ericaceae associate with ericoid mycorrhizal (ERM) fungi for survival. In this study fungal biomass accumulation in vitro was used to determine nutrient utilisation of various inorganic and organic substrates. This is an initial step towards establishment of the ecological roles of typical ERM fungi and other root fungi associated with Erica plants, with regard to host nutrition. Meliniomyces sp., Acremonium implicatum , Leohumicola sp., Cryptosporiopsis erica , Oidiodendron maius and an unidentified Helotiales fungus were selected from fungi previously isolated and identified from Erica roots. Sole nitrogen sources ammonium, nitrate, arginine and Bovine Serum Albumin (BSA) were tested. Meliniomyces and Leohumicola species were able to utilise BSA effectively. Phosphorus nutrition was tested using orthophosphate, sodium inositol hexaphosphate and DNA. Most isolates preferred orthophosphate. Meliniomyces sp. and A. implicatum were able to accumulate significant biomass using DNA. Carbon utilisation was tested using glucose, cellobiose, carboxymethylcellulose, pectin and tannic acid substrates. All fungal isolates produced high biomass on glucose and cellobiose. The ability to utilize organic nutrient sources in culture, illustrates their potential role of these fungi in host nutrition in the fynbos ecosystem. [ABSTRACT FROM AUTHOR]

Rose's mountain toad Capensibufo rosei survives in a few isolated montane populations in the south-western Cape of South Africa. It comprises several cryptic species but it is uncertain whether the lineage on the Cape Peninsula is distinct. We tested the hypothesis that toads from the Peninsula form a single genetic lineage but that different breeding sites are divergent at a population level as a result of limited dispersal abilities. Directed surveys were carried out to locate breeding sites and samples obtained were analysed in a phylogenetic and population genetic framework, using two mitochondrial markers. We found toads breeding at only one of five known historical breeding sites, although one new breeding site was also recorded. No toads were observed at 15 other non-breeding localities where they were historically observed. Toads from the two active breeding sites formed a single lineage that was sufficiently distinct to be given species status. However, these were discrete at a population level, with no shared haplotypes, suggesting no gene flow between sites. One site was particularly low in genetic diversity, implying increased vulnerability to stochastic events and elevated risk of extinction. These results, coupled with the failure to locate historically known sites on the Cape Peninsula, make this newly recognized Peninsula endemic a conservation priority. Efforts should focus on the protection and expansion of the two known surviving populations and the patches of habitat upon which they rely. [ABSTRACT FROM PUBLISHER]

We investigated ecological separation through dietary partitioning of small mammals in the nutrient-poor Fynbos biome using a stable isotope approach. Hair samples from eight species of co-occurring small mammals in two separate locations were analysed for stable carbon (13C/12C) and nitrogen (15 N/14N) isotope ratios. In addition, we investigated the seasonal variation in diet again by using variation in isotopic composition of one of the most common small mammal species, the Cape spiny mouse. We also analysed seeds and leaves from the most common plant species at each study site. Results showed that some dietary separation exists among these coexisting small mammals. Geographic differences exist in isotope signatures within the Cape spiny mouse, possibly resulting from area-related variations in isotope values of plants, as well as differences in the animals' diets. A. subspinosus hair shows little to no seasonal fluctuation of isotopic signals, except in summer, which possibly indicates a stable diet over much of the year . We conclude that the isotopic approach to determine trophic levels is limited by significant geographic variation in plant isotopes and enrichment in seeds compared to leaves. [ABSTRACT FROM AUTHOR]

The protea seedeater, is one of Crithagra leucopterus, six passerine birds endemic to the Fynbos Biome, South Africa. It is the least known of these, and there is very little information on breeding and habitat use. Through nest observations and a bird ringing scheme in the eastern sections of the Fynbos, we provide updated information on habitat use, breeding and population biometrics. We document changes in capture rates for a suite of birds in relation to a fire event and use of burnt and unburnt sites within Blue Hill Nature Reserve, South Africa. Protea seedeaters were recorded nesting in mature Fynbos, but feeding in recently burnt Fynbos on freshly released protea seeds, suggesting the species benefits from small-scale burns that create a landscape of mixed veld ages. Protea seedeaters weighed less and had shorter wings compared to those of the western Fynbos. Further habitat-use and life-history information on protea seedeaters is needed to help guide conservation management plans, especially in the light of changing fire regimes in the Fynbos. [ABSTRACT FROM AUTHOR]

Aims: Bark thickness-stem diameter relationships are non-linear above a stem diameter threshold inmany woody species, whichmakes relative bark thickness measures dependent on the range of stem diameters that are sampled. This influences the appropriateness of differentmethods for comparing fire responses of woody plants across studies. Here we develop a framework for bark thickness comparisons by evaluating relative bark thickness estimates and bark thickness predictions obtained from linear and curved models fitted to raw and log-transformed bark-stem data. We use this framework to contrast bark thickness among fynbos and savanna plant functional groups. Location: Fynbos (17 species) and savanna (21 species) systems in South Africa. Methods: The linear subset of bark-stem data was identified using a three-step procedure. Linear regressions (with and without an intercept) and curved models (allometric and modified exponential models) were fitted to the linear subset and complete raw bark-stem data set, respectively. In addition, linear regression models were fitted to the log-transformed complete bark-stem data set. Regression slopes and bark thickness predictions obtained from these different approaches were compared, to determine which method provides the most robust metric for comparing bark thickness. Bark thickness was compared among fynbos resprouter guilds and acacias fromlow- and high-fire savannas. Results: The slope of the regression model fitted to the linear subset of raw bark-stem data provides a reliable metric for general comparisons of relative bark thickness. Bark thickness predictions from the curved and log models were comparable at 20-cm stem diameter, but the log model underestimated bark thickness at 5 cm for certain species. Relative bark thickness was significantly higher in: (1) fynbos fire resisters and epicormic resprouters than in non-resprouters; and (2) acacias fromhigh- vs low-fire savannas. Conclusions: The slope of the regressionmodel fitted to the linear subset of raw bark-stem data is a useful metric for bark thickness comparisons across studies, and compares favourably with bark thickness predictions derived from models fitted to the complete bark-stem data set. Fynbos and savanna trends support the proposition that relative bark thickness reflects differences in woody plant responses to fire and indicate themodal fire regime of ecosystems. [ABSTRACT FROM AUTHOR]

Aspalathus linearis (rooibos) is a medicinally and economically useful shrub which is endemic to the Mediterranean west coast region of South Africa. Species distribution modelling indicates potentially severe consequences in range shift for rooibos tea under the changing climate conditions. However, they are based on several assumptions and simplifications which may compromise future predictions. In an effort to improve the accuracy of the species distribution model, results obtained from the modelling were used to further investigate the species' climatic limits through experimental manipulation of drought. Water limitation was associated with significant decreases in net photosynthesis, stomatal conductance, and transpiration in A. linearis . The inhibitory effects of drought on photosynthetic parameters had a concomitant effect on biomass accumulation and nutrient allocation. Hence, the projected increase in aridity for the rooibos production region is expected to reduce productivity of commercially cultivated tea. However, rooibos demonstrated certain adaptation mechanisms to adverse conditions by increasing water use efficiency, developing a higher level of sclerophylly and altering the allocation of plant reserves by increasing the flow of assimilates to the roots. The ability of the species to partially offset the negative effects of water deficit stress may enable seedlings to survive and persist, albeit with reduced biomass. [ABSTRACT FROM AUTHOR]

Abstract: The effect of germination incubation regimes, which were chosen on the basis of temperature patterns found within the fynbos (Mediterranean fire-prone shrubland-type) habitat in the Cape Floristic Region during the autumn germinative period, was tested on seeds of 6 Leucospermum species over 5 taxonomic sections (L. cordifolium, L. cuneiforme, L. erubescens, L. glabrum, L. reflexum, L. vestitum ). Seeds of each species were scarified, soaked in water and incubated at 15 combinations of diurnal low (16h) and high (8h) temperatures. The results indicated that Leucospermum seeds generally require alternating temperatures for germination. Regression analysis of germination percentage responses were used to estimate provisional optimum low [T O(LOW)] and optimum high [T O(HIGH)] temperature requirements for individual species. These requirements differed markedly among species, and across species they averaged 9.9 and 21.2°C, respectively. Individual requirements correlated positively with mean late autumn air temperatures obtained from weather stations near the natural habitats of species. We conclude that a diurnal alternating temperature requirement is a character syndrome in Leucospermum in which the T O(LOW) and T O(HIGH) components are narrowly adaptive, independent and genetically stable characters relating to the known ecophysiological roles of low and high temperature requirements (Brits, Cutting, Brown and Van Staden, 1995). Ecological and adaptive roles of these requirements are compared with those in some persistent small-seeded soil-stored seed banks. [Copyright &y& Elsevier]

Temporary depression wetlands form a characteristic feature of the wet-season landscape in the south-western Cape region of South Africa, yet they remain largely unstudied. We hypothesized that the loss of sclerophyllous Sand fynbos habitat around these temporary wetlands causes in-wetland physico-chemical changes. We expected to observe a decrease in the concentration of humic substances in wetlands and a corresponding rise in surface water pH as fynbos cover decreases around wetlands, in this case owing to alien vegetation invasion. A set of 12 differentially invaded temporary depression wetlands within a Sand fynbos ecosystem in Cape Town were repeatedly sampled during the 2009 wet season. Multivariate gradient analysis techniques revealed associations between fynbos cover bordering wetlands and various physico-chemical and biotope constituents within wetlands. Univariate linear regression models reported strong and temporally consistent negative relationships between terrestrial fynbos vegetation cover and wetland pH and positive relationships with humic content. Results indicate that replacement of Sand fynbos with alien vegetation causes a reduction of humic input to wetlands, which in turn has knock-on effects on other wetland environmental constituents such as pH. These findings are expected to be applicable to any wetland where surrounding humic-rich sclerophyllous vegetation is replaced by a non-sclerophyllous agent. [ABSTRACT FROM AUTHOR]

Abstract: Global changes are influencing fire regimes in many parts of the world. In the Fynbos plant diversity hotspot (Cape Floristic Region, South Africa), fire frequency has increased in protected areas where the mean fire interval went from 12–19 to 6–9 years between 1970 and 2000. Fire is one of the main drivers of plant diversity in the Cape Floristic Region. Too frequent fires threaten the persistence of slow-maturing plant species, and such insights have led to the adoption of fire management principles based on plant responses. The effects of fire on Fynbos fauna are much more poorly understood, and have not generally been considered in depth in Fynbos conservation policies, planning or management. We assessed the response of bird communities to long-term fire-induced vegetation changes using space-for-time substitution. We studied bird communities, vegetation structure and plant functional composition in 84 Fynbos plots burnt between two and 18 years before. Ten of the 14 bird species analysed showed a significant change in their abundance with time since fire. We observed a significant species turnover along the post-fire succession due to changes both in vegetation structure and plant functional composition, with a characteristic shift from non-Fynbos specialists and granivorous species to Fynbos specialists and nectarivorous species. If current trends of increasing fire frequency continue, Fynbos endemic birds such as nectarivores may become vulnerable. Conservation management should thus aim more carefully to maintain mosaics of Fynbos patches of different ages. Future research needs to estimate the proportion of vegetation of different ages and patch sizes needed to support dependent fauna, particularly endemics. [Copyright &y& Elsevier]

Background and aims Species in plant communities segregate along fine-scale hydrological gradients. Although this phenomenon is not unique to fynbos, this community regenerates after fire and therefore provides an opportunity to study the ecological genesis of hydrological niche segregation. Methods Following wildfires at two field sites where we had previously mapped the vegetation and monitored the hydrology, seeds were moved experimentally in >2500 intact soil cores up and down soil-moisture gradients to test the hypothesis that hydrological niche segregation is established during the seedling phase of the life cycle. Seedling numbers and growth were then monitored and they were identified using DNA bar-coding, the first use of this technology for an experiment of this kind. Key Results At the site where niche segregation among Restionaceae had previously been found, the size of seedlings was significantly greater, the wetter the location into which they were moved, regardless of the soil moisture status of their location of origin, or of the species. Seedling weight was also significantly greater in a competition treatment where the roots of other species were excluded. No such effects were detected at the control site where niche segregation among Restionaceae was previously found to be absent. Conclusions The finding that seedling growth on hydrological gradients in the field is affected by soil moisture status and by root competition shows that hydrological niche segregation could potentially originate in the seedling stage. The methodology, applied at a larger scale and followed-through for a longer period, could be used to determine whether species are differently affected by soil moisture. [ABSTRACT FROM PUBLISHER]

Serotiny, the retention of mature seeds in closed fruits within the canopy for over a year, is a common trait in fire-prone environments. When competition with adult plants prevents seedling establishment between fire events and in the absence of post-release soil seed dormancy, strong serotiny, i.e. the retention of all seeds until the next fire, appears as the best strategy. Despite the low levels of inter-fire seed recruitment for several species in both Australian and South African fire-prone environments, considerable variation in the duration of fruit retention is nevertheless observed among species., Our aim is to predict optimal age-specific reproductive schedules in a perennial, serotinous species, when cone maintenance is costly. We focus on species where adults are killed by fire, without a soil seed-bank. We explicitly consider a trade-off between growth (which determines plant survival), seed production and seed maintenance. In our model recruitment relies upon fire events. We use dynamic programming to determine, for given fire regimes, the optimal pattern of resource allocation. We further study the effect of changes in fire regime on the viability of populations adapted to some historical fire regime., We find that, whenever maximal plant survival probability is low, the optimal strategy consists in reducing resource allocation to seed maintenance while increasing resource allocation to annual seed production. This illustrates a trade-off between current and future reproduction., A low rather than a strong level of serotiny should evolve whenever the variance of fire intervals is large and the mean fire interval is low. Low levels of serotiny could constitute a bet-hedging strategy with decreasing predictability of the arrival of fire., Once adapted to some historical fire regime, serotinous populations are highly sensitive to a change in mean fire frequency and to an increase in the variance of fire intervals. Populations adapted to a historically high level of variance in fire return are more robust to changes in fire regime., Synthesis: Life-history trade-offs and low predictability of fire intervals may favour low rather than strong levels of serotiny even when recruitment essentially occurs just after fire events. [ABSTRACT FROM AUTHOR]

The article focuses on proteaceae, a flowering plant belonging to the Fynbos biome. It states that proteaceae plays an important role in the proper functioning, conservation and economic use of fynbos. It further focuses on a research conducted by the South Africa's Council for Scientific and Industrial Research in 1977. It also informs about the proteaceae demography, a technique used for understanding the dynamics of species and communities.

Abstract: The addition of carbon (C) to the soil as sucrose has been suggested as a countermeasure to reduce plant available nitrogen (N) and increase the competitive advantage of slower growing native perennial species over faster growing annual species. To make this approach a successful restoration tool, C addition must induce the resident soil bacteria and fungi to immobilize plant available soil nutrients. In this study, both the efficacy of sucrose applications as a restoration aid and their dependence on soil microbial activity were examined in field and greenhouse trials. Carbon as sucrose (200gm−2) was added to normal and sterilized soils containing various combinations of native perennial and annual species. Their effects on soil N levels, as well as on the photosynthetic efficiency, growth and N uptake of the introduced native species, were measured. Diminished foliar chlorophyll contents, effective quantum yields (ΔF/Fm′) of Photosystem II (PSII) and dry mass accumulation in response to sucrose applications were observed in both the annual and perennial introduced species, but were not reflected in corresponding reductions in soil N levels. These sucrose-induced inhibitory effects, as well as diminished plant N uptake, were more pronounced in normal than sterilized soils. This implied a bacterial component immobilizing soil N essential for plant photosynthesis and growth. However, this premise was partly contradicted by the unaltered total bacterial numbers following sucrose application in the normal soils, although coliform numbers did increase with sucrose application in these soils. These findings point to a likely abiotic mechanism of sucrose-induced inhibition of photosynthesis and growth in introduced native plants, which renders sucrose application ineffectual as a restoration aid in transformed lowland fynbos ecosystems. [Copyright &y& Elsevier]

We examined whether extensive dry season dieback and mortality in a South African fynbos community were due to drought or pathogen attack. Plant dieback and mortality have been reported elsewhere in similar plant communities suggesting potential for a widespread climatic or biotic threat to this community. We collected tissue samples from Brunia noduliflora, the dominant plant in the community, and cultured them for potential plant pathogens. We also measured dry season predawn and midday water potentials of healthy and stressed plants and constructed pressure-volume curves to assess turgor loss point. Plant stress and mortality were monitored over a 2-year study period. Both healthy plants and plants that displayed moderate signs of stress had dry season predawn water potentials well above their turgor loss point suggesting plants were not water stressed. However, plants displaying >60% crown dieback had much lower water potentials (as low as −12 MPa). A previously undescribed fungus ( Pythium sp.) was isolated from the root vascular tissue of all stressed plants and was not present in healthy plants. The proximate cause of plant stress was likely pathogen-induced, while the ultimate cause of plant death appears to be extreme water stress. The present study suggests that Brunia (Bruniceae), Leucadendron (Proteaceae) and Erica (Ericaceae), all emblematic and dominant genera within the diverse fynbos community, may be susceptible to Pythium infection. This may pose a serious threat to communities already threatened by climate change. [ABSTRACT FROM AUTHOR]

Abstract: The Western Cape of South Africa is characterized by the hyperdiverse vegetation of the Fynbos biome. Typical fynbos vegetation is a fire-adapted sclerophyllous Mediterranean-type ecosystem on poor, sandy or stony soils. It is characterized by plants with low nutrient content producing slowly decomposing litter. Fire is recognized as a major factor for carbon and nutrient cycling in this vegetation type. However, knowledge of biological decomposition processes in this biome is limited. We used litter-bags to measure mass loss and changes in chemical composition in litter from three species representing characteristic taxa in fynbos, a Protea exima hybrid, Erica multumbellifera, and Restio multiflorus, during approximately 180 days. In addition, we used a standard litter of a species with high nutrient content, Galenia africana, and a mixture of Protea and Erica. We compare our results with a previous study from renosterveld including the geophyte Watsonia borbonica, which occurs in both vegetation types and occurs commonly in the study area. We found that decomposition rate among the true fynbos plant species P. exima, E. multumbellifera, R. multiflorus and W. borbonica varied almost eight-fold. Litter decomposition was strongly correlated to litter stoichiometry, i.e. C/N and C/P-ratios. Most litters accumulated one or several nutrients during the study period. The mixture of litters decomposed faster than expected from the results of each litter separately. Our study indicates that biological decomposition may be more important for carbon and nutrient cycling in fynbos than previously thought. These results are in accordance with recent studies showing large variation in plant litter quality within vegetation types and biomes. Such large variation in litter quality and decomposition rate suggests that some generalisations about ecosystem processes in the fynbos may need reevaluation. [Copyright &y& Elsevier]

The Table Mountain National Park is a 265-km² conservation area embedded within a city of 3.5 million people. The highly diverse and unique vegetation of the park is both fire prone and fire adapted, and the use of fire forms an integral part of the ecological management of the park. Because fires are both necessary and dangerous, fire management is characterized by uncertainty and conflict. The response of vegetation to fire is reasonably well understood, but the use of fire for conservation purposes remains controversial because of key gaps in understanding. These gaps include whether or not the vegetation is resilient to increases in fire frequency, how to deal with fire-sensitive forests embedded in fire-prone shrublands, and how to integrate fire and invasive alien plant control. National legislation emphasizes the need to protect communities from dangerous wildfires, and this compels fire managers to adopt a cautious approach to the application of fire. Ecological outcomes are optimized under a fire regime of relatively high-intensity, dry-season fires. Obtaining permission to burn under such conditions is not possible, and so the practice of prescribed burning is constrained, and this results in a fire regime dominated by wildfires. Ecological uncertainties, and the divergent requirements for maintaining healthy ecosystems on the one hand, and ensuring human safety on the other, result in a complex fire management environment. These complexities could be, and in some cases are being, alleviated by raising awareness, increasing fire management capacity, improving ecological monitoring of the effects of fire, and prioritizing areas for integrated fire and invasive alien plant management. [ABSTRACT FROM AUTHOR]

Post-fire recovery trajectories of five fynbos vegetation stands in the Western Cape Region of South Africa were characterized using moderate-resolution imaging spectroradiometer (MODIS) normalized difference vegetation index (NDVI) 250 m data. Indices of NDVI recovery relative to pre-fire values or values from unburnt control plots indicated full recovery within 7 years and particularly rapid recovery in the first two post-fire years. Intra-stand variability of pixel NDVIs generally increased after fires and also exhibited a rapid recovery to pre-fire conditions. While stand age was the dominant determinant of NDVI recovery, drought interrupted the recovery pathways and this effect was amplified on drier, equator-facing slopes. Post-fire recovery characteristics of fynbos NDVI were found to be similar to those documented for chaparral vegetation in California despite contrasting rainfall and soil nutrient conditions in the two regions. [ABSTRACT FROM AUTHOR]

Pollen analysis of a core in Princess Vlei in the Fynbos Biome near Cape Town gives a 4150 year record of vegetation and climate changes followed by disturbance by colonial settlers since c. 300 years ago. Their impact replaced climate as a major factor in changing the vegetation. The chronology is based on eight radiocarbon dates. Pollen types such as Restionaceae, Ericaceae, and Proteaceae reflect changes in fynbos. Pollen indicators at the bottom of the core suggest drier conditions followed by an increase in Morella, Cyperaceae and Carpacoce pollen, which might indicate moist conditions c. 3400–2600 cal. yr BP. Drier conditions prevail c. 2600–1900 cal. yr BP. Apparent light disturbance after c. 2000 cal. yr BP might be attributed to Khoi herders. Deeper water and damp surroundings are indicated c. 1900–1000 cal. yr BP. The top of the core shows an increase of Poaceae while Restionaceae decrease with anthropogenic disturbance, including the introduction of neophytes such as Pinus (c. 300 years ago) and Zea mays. Charcoal percentages point to intense fires after the arrival of the Europeans. Water between 105 and 75 cm indicates the development of a floating mat resulting from changes in the hydrological system possibly connected to disturbances by settlers. [ABSTRACT FROM PUBLISHER]

Invasive species alter the functioning of natural ecosystems, creating 'novel ecosystems' comprising species occurring in combinations with no analogs within a given biome. This poses major challenges for managers who cannot rely exclusively on previous experiences. Multiple factors that drive invasion and which interact in complex ways demand innovative management approaches. We show the utility of scenario planning in considering options for management in a region with substantial problems with invasive alien plants: South Africa's Cape Floristic Region. The approach allows us to identify the driving forces that shape the status and trajectories of major woody invasive plants and to identify sensible strategies by considering a set of scenarios based on the main uncertainties that encapsulate the linkages between the various components of the management of biological invasions. Attitudes of landowners and management capacity are shown to be the crucial uncertainties influencing the spread of major invasive species; axes based on these factors define our scenarios. Mapping current management projects onto scenario axes highlighted key differences among areas. These insights can assist in directing particular management units toward more desirable futures. Our study highlights the need to link social, political and legal constraints with ecological processes to assure the effectiveness of management operations in controlling biological invasions. [ABSTRACT FROM AUTHOR]

Outside their natural range, honeybees ( Apis mellifera) are known to have detrimental effects on indigenous pollinators through exploitative or interference competition, but little is known about the effect of honeybee farming in areas where honeybees occur naturally. In the Cape Floristic Region of South Africa, where honeybees are indigenous, managed hives potentially elevate the abundance of honeybees far above natural levels, but impacts on other floral resource-dependent species have not been studied. Here we use experimental manipulation of honeybee density to test whether honeybee farming affects nectar-feeding birds. We selected the common sugarbush ( Protea repens), utilized by both birds and bees, and analysed the time (before/after) by treatment (control/experiment) interaction to explore changes in bee abundance, nectar availability and bird abundance at three sites. Hive addition increased honeybee abundance in inflorescences of P. repens above expected levels. Despite experimental increase in honeybee numbers, there is no reduction in nectar sugar availability relative to the control areas. Where honeybee density was highest, sugarbird ( Promerops cafer) numbers declined relative to expected, but sunbirds (Nectarinidae) were not affected at any of the sites. We conclude that stocking rates of more than one honey bee per P. repens inflorescence have detrimental effects on bird abundance due to interference, rather than resource competition. [ABSTRACT FROM AUTHOR]

Abstract: The Mountain Renosterveld vegetation of the Roggeveld is an escarpment type renosterveld showing strong karroid affinities. Fire plays an important role as a landscape scale disturbance that shapes plant communities in this vegetation type, however, post-fire succession has never before been documented for renosterveld vegetation. A study was therefore conducted in the northern Roggeveld to improve our understanding of the recovery of the vegetation following fire. The natural vegetation recovery was analysed using line transect data accumulated at five different sites over a ten year period. This paper reports on the post-fire vegetation trends with respect to changes in species composition, species richness, life form composition and life form richness. Vegetation cover began to re-establish within the first nine months following the fire, and remained at a high level from years 3 to 10. At the first survey the species richness varied from 13 to 17 species, with the highest species richness (14 to 31 species) generally encountered at each transect after three years. The highest Shannon index values were generally found within the first three years and the lowest Shannon index values were found in years 9 and 10. In all cases the Principal Co-ordinate Analysis ordinations of the species composition data indicated a clear separation in the species composition between the first two years (years 1 and 2) following the fire and the remaining years (year 3 to 10). This study also supports the ‘initial floristic composition’ model of Egler (1954) in that all or the majority of species encountered during the succession were already present at the beginning of the recovery phase and there was a rapid re-establishment of the initial plant community. [ABSTRACT FROM AUTHOR]

Abstract: The City of Cape Town (City) covers 2460km2 in the southwestern corner of the Cape Floristic Region biodiversity hotspot. Established in 1654, by 1700 there were no animals larger than 50kg within 200km of the City. However, apart from an appreciation that timber and firewood were becoming scarce, it was only in the 1930s that the first farm near Cape Point was set aside for conservation. Table Mountain was declared a National Monument in 1958, while it was largely covered by pine and gum plantations. Conservation of the montane areas thereafter expanded, whereas the lowlands were largely ignored, except for a few bird sanctuaries. Only in 1982 was the plight of the lowlands highlighted. Although ad hoc conservation planning was undertaken subsequently, 1997 saw the first priority categorization and conservation plan. The current situation is perilous: a huge effort will be required to meet basic conservation targets for the lowland vegetation types and threatened species. Local and international partners and funders will be key to achieving this. In eight of the City''s 19 national vegetation types the minimum conservation targets are not achievable. Of the 3250 plant species estimated to occur in the City, 13 are extinct and 319 are threatened according to the IUCN Red List: this is 18% of the threatened Red List species in South Africa. Now for the first time, implementation is being attempted holistically across the metropole with discussion between internal City and external stakeholders to implement the conservation plan. However, the interim plans towards achieving this — that 60% of the unproclaimed target is secured by 2014, requires that over 40km2 be conserved per annum. This leaves 340km2 that should be secured by 2020 when projections from City spatial growth indicate that the last critical remnants will be urbanized. [Copyright &y& Elsevier]

Abstract: The Western Cape region of South Africa is home to a unique type of mediterranean vegetation called fynbos, as well as some of the earliest sites of modern human occupation in southern Africa. Reconstructing the paleohabitats during occupations of these early anatomically modern Homo sapiens is important for understanding the availability of resources to the humans during the development of behaviors that are often considered advanced. These reconstructions are critical to understanding the nature of the changes in the environment and resources over time. Here we analyze the craniodental fossils of the larger mammals recovered from two Pleistocene assemblages in the Pinnacle Point complex, Mossel Bay, Western Cape Region, South Africa. We reconstruct the paleohabitats as revealed by multivariate analyses of the mammalian community structures. Pinnacle Point 30 is a carnivore assemblage and Pinnacle Point 13B includes early evidence of a suite of modern human behavior; together they present an opportunity to identify environmental change over time at a localized geographic scale. Further, this is the first such study to include dated Western Cape localities from Marine Isotope Stage 6, a time of environmental pressure that may have marginalized human populations. Results indicate that environmental change in the Western Cape was more complex than generalized C4 grassland expansions replacing fynbos habitats during glacial lowered sea levels, and thus, resources available to early modern humans in the region may not have been entirely predictable. [ABSTRACT FROM AUTHOR]

1. Fire is an important process in Mediterranean-ecosystem shrublands, and prescribed burning is often used to manage these ecosystems. Analyses of past fire regimes are required to interpret biotic responses to fire, as well as to assess the degree to which management interventions have been able to influence the fire regime. 2. We used a spatial data base of fires within 10 protected areas covering >720 000 ha to examine the frequency, seasonality, size and cause of fires over four decades. Our study covered five fire climate zones and a range of mountain fynbos shrubland types. We examined whether regular prescribed burning would be necessary to rejuvenate the vegetation, and also to reduce the incidence and extent of wildfires. 3. Cumulative fire frequency distributions indicated that the probability of fire was not strongly affected by post-fire age, with 50% of the area experiencing a successive fire within 10–13 years after the previous fire in most areas. This suggests that the accumulation of fuel did not limit the occurrence of wildfires, and that regular prescribed burning would not necessarily reduce the risk of wildfires. 4. Inland zones experienced more severe fire weather than coastal zones (∼35% vs. 11–19% of days with high to very high fire danger, respectively). Despite these differences, fire return periods were similar (10–13 years), suggesting that the availability of ignitions, and not fuel or weather, limited the occurrence of wildfires. 5. Despite a policy that promoted prescribed burning, a relatively small area (between 4·6% and 32·4% of the area of all fires) burned in prescribed burns. Seasonal restrictions for safety and ecological reasons, the imperative to integrate planned fires with invasive alien plant treatments and unplanned wildfires have all contributed to the relatively small area that burnt in prescribed burns. 6. Synthesis and applications. Recurrent wildfires,... [ABSTRACT FROM AUTHOR]

Abstract: There are many variables within an urban landscape that can be expected to influence faunal diversity. We used a mechanistic approach to observe the relative importance of each of these variables in describing the diversity of avian communities in urban and peri-urban areas of Cape Town, South Africa situated within Cape Floristic Region, a global plant biodiversity hotspot. We expected to find a strong influence of habitat amount and arrangement across a fragmented urban–rural gradient. Birds were sampled in patches of fragmented Cape Flats Sand Fynbos at 39 locations during the middle of summer (November–January 2008/2009). Environmental data included on-site observations, existing GIS layers, and remotely sensed data. Bird community composition was related to habitat amount, arrangement, and quality. Correlations, partial correlations and structural equation analysis showed that habitat amount and arrangement had insignificant effects on species richness across the urban gradient. Changes in urban density and the presence or absence of the invasive alien tree species Acacia saligna (blue wattle) appeared to be the main drivers of avian species richness. Increasing urban density, decreasing A. saligna density and decreasing canopy height correlated with higher avian species richness, with confounding variables corrected for. For the management of urban biodiversity, our results suggest that the most urgent focus should be on retaining the quality remaining areas of native vegetation (and particularly, containing the spread of A. salgina) rather than extending current networks with poor quality habitat. More generally, habitat quality appears to be more important than habitat amount or arrangement in this system. We suggest that this observation be encorporated into further research to more effectively predict avian responses to landscape change and that more must be done to adequately capture the critical and complex role of the matrix in terrestrial systems. [Copyright &y& Elsevier]

Abstract: We investigate here invertebrate response to alien pine plantations, their removal in comparison with natural vegetation, recovering indigenous forests and a botanical garden around Cape Town, South Africa, within a biodiversity hotspot. Pines had low invertebrate species richness and abundance. The botanical garden had the highest species richness and abundance. Natural fynbos vegetation was more similar to pines than to recovering fynbos, while recovering forest was more similar to pines than to any other site. The botanical garden is a major refugium for invertebrate species. Surprisingly, invertebrate assemblages in natural fynbos were more similar to those in pines than in recovering fynbos after the removal of pines. This suggests that some invertebrate species colonize the fynbos soon after rehabilitation disturbance, a response similar to the influence of fire. However, it takes longer for other natural climax invertebrate species to establish, some of which find refuge in pines and the botanical garden. Invertebrate assemblages of indigenous natural forests are more difficult to restore than those of fynbos, thus the protection of the remaining natural forests is a conservation priority. Invasive alien Argentine ant (Linepithema humile) was far more abundant in recovering fynbos than in natural fynbos or in the botanical garden and pines. It benefits from initial restoration disturbance, although is likely to decline as the natural fynbos mature. This study strongly supports removal of alien pines in an urban context, and also emphasizes that an urban botanical garden of indigenous plants has major invertebrate conservation value. [Copyright &y& Elsevier]

Abstract: In an attempt to reconcile wildflower cultivation with plant diversity conservation, we investigate the effect that different augmentation techniques (including ploughing and burning) have on the plant diversity of the Fynbos Biome. We evaluated the effects of two ploughing intensities followed by augmentation at one site, and augmentation without ploughing at another on the plant diversity in Overberg Sandstone fynbos on the Agulhas Plain, South Africa. Results showed that plant diversity was the highest in areas which were either shallow-ploughed and augmented or augmented only; thus these treatments appear not to have a significant negative effect on plant diversity at least in the short-term. Deep ploughing, however, was detrimental to plant diversity. Results could be explained by the intermediate disturbance hypothesis i.e. intermediate levels of disturbance prevent the competitive exclusion of subdominant species. The conclusion drawn from this study is that low-intensity cultivation of commercial fynbos species can be diversity-friendly, but high-intensity disturbance practices should be avoided. [Copyright &y& Elsevier]

Abstract: Invasive alien trees and shrubs pose significant threats to biodiversity and ecosystem services in South African fynbos ecosystems. An ambitious initiative, the Working for Water program, commenced in 1995 to reduce the extent and impact of plant invasions. Despite substantial progress, the problem remains immense, and innovative ways of improving the efficiency of control operations are urgently needed. This study sought to develop a robust conceptual framework for effective management of the most important invasive alien plant (IAP) species. Two methods were applied in exploring the complexity of problems, thereby identifying appropriate response strategies. The DPSIR (Driving forces-Pressure-State-Impacts-Responses) framework and the Analytic Hierarchy Process (AHP) tool were used to design a strategy for prioritizing management actions. This strategy considers explicitly the most influential factors that determine the distribution, abundance, spread and impacts of IAPs. Efficient management of IAPs is constrained by multiple interacting environmental and socio-economic factors. Factors related to the fire-prone nature of the ecosystem and the characteristics of the invasive stands emerged as pivotal features for setting spatially-explicit priorities for management. Results of the analyses provide an objective and quantifiable perspective for improving the management efficiency. We conclude that considerable progress in controlling the spread of IAPs in fynbos ecosystems could be achieved by better coordination of management practices and by improving the quality of species distribution data. [Copyright &y& Elsevier]

Gene flow between related plant species, and between transgenic and non-transgenic crop varieties, may be considered a form of biological invasion. Brassica napus (oilseed rape or canola) and its relatives are well known for intra- and inter-specific gene flow, hybridisation and weediness. Gene flow associated with B. napus poses a potential ecological risk in the Fynbos Biome of South Africa, because of the existence of both naturalised (alien, weedy) and native relatives in this region. This risk is particularly pertinent given the proposed use of B. napus for biofuel and the potential future introduction of herbicide-tolerant transgenic B. napus. Here we quantify the presence and co-occurrence of B. napus and its wild and weedy relatives in the Fynbos Biome, as a first step in the ecological risk assessment for this crop. Several alien and at least one native relative of B. napus were found to be prevalent in the region, and to be spatially congruent with B. napus fields. The first requirement for potential gene flow to occur has thus been met. In addition, a number of these species have elsewhere been found to be reproductively compatible with B. napus. Further assessment of the potential ecological risks associated with B. napus in South Africa is constrained by uncertainties in the phylogeny of the Brassicaceae, difficulties with morphology-based identification, and poor knowledge of the biology of several of the species involved, particularly under South African conditions. [ABSTRACT FROM AUTHOR]

Mountain fynbos catchments in the Western Cape region of South Africa are prone to substantial changes in land cover due to invasion by exotic tree species (and their clearing), fires, and vegetation response to inter-annual variations in rainfall. While small catchment experiments and modelling studies have pointed to reductions in river flow as catchment biomass increases, there is little empirical evidence of land cover change affecting river flow in large catchments that are important sources of water for the region. Monitoring changes in above-ground green biomass in multiple large catchments is challenging, but may be accomplished using a remotely sensed spectral vegetation index. It was hypothesised in this study that annual river yield (river flow as a fraction of rainfall) in the Molenaars catchment near Paarl, South Africa co-varies with an index of green vegetation cover derived from satellite data (the normalised difference vegetation index, NDVI). The catchment was partitioned into 'upland' and 'lowland' zones and the relationship between annual river yield and summer NDVI was determined for each zone over an 18-year period. There was a statistically significant negative linear relationship between annual river yield and the NDVI of the lowland zone when three outliers were excluded from the analysis. These outliers corresponded to periods with prolonged drought conditions when river yield appeared to be decoupled from vegetation water use in the lowland zone. There was no relationship between river yield and changes in the NDVI in the upland zone where plants were unlikely to have sustained access to adequate soil water for transpiration. The importance of considering the location of land cover changes in a catchment, and inadequacies in high-elevation measurements of rainfall in this mountainous region, were highlighted in the study. [ABSTRACT FROM AUTHOR]

Abstract: In 1998, a restoration field trial was initiated in a catchment near Wellington (Western Cape, South Africa) to determine whether fynbos riparian scrub vegetation cleared of woody invasive alien trees require post-clearance restoration actions to accelerate indigenous vegetation recovery. The aim was to assess the relative effectiveness of three sowing treatments for restoring indigenous vegetation cover after the widely used “Fell & Burn” method of clearing invasive alien trees. Sowing treatments included non-invasive alien grasses to determine whether they have a negative effect on recovering native vegetation. A summer fire, eight years after trial initiation, provided an opportunity to determine how resilient restoration treatments are to alien re-invasion and fire. Restoring the site after alien clearing by sowing indigenous seeds increased both diversity, by improving species presence and abundance. However, a census done 8 years later (in 2006) revealed that seedlings of woody invasive alien plants dominated all plots, and had also survived the burn by resprouting, indicating the importance of follow-up control to justify initial clearing and restoration costs. Indigenous grass density was significantly reduced in plots where alien grasses were sown, while in the control and fynbos sowing treatment, indigenous grass density increased. By 2006, alien grass density was negligible in all treatments, indicating that the two grass species sown are not persistent or invasive. Active restoration of riparian areas after alien plant clearing has potential to facilitate vegetation recovery, but must be coupled with a long-term plan for adequate follow-up removal of post-clearance and post-fire alien recruits. [Copyright &y& Elsevier]

Abstract: The Working for Water programme is tasked with the important role of controlling invasive alien plants with an assumption that indigenous vegetation will recover naturally. This study assessed vegetation composition and structure following alien clearance in closed-stand invasion of riparian areas and a minimum of two years'' passive recovery. Three initial clearing treatments — Fell Only, Fell & Remove and Fell & Burn — were compared to uninvaded Reference conditions. The aim was to ascertain the nature of vegetation recovery, as well as to determine which clearing treatment was most successful in promoting recovery. A Detrended Correspondence Analysis revealed that the Fell & Remove treatment most closely approached the Reference condition while Fell Only and Fell & Burn plots had altered composition and structure. All clearing treatments had significantly lower vegetation cover than the Reference and species composition was altered by invasion and clearance. Important growth forms, such as small (3–10 m) trees were suppressed by felled slash and burning. Although burning was the best method to reduce woody alien species, secondary invasion by alien herbaceous species occurred where natural riparian vegetation did not re-establish. The Fell & Remove treatment is recommended as the best to use in promoting indigenous vegetation recovery, and together with continued alien follow-up control, is able to minimize alien re-invasion of riparian ecosystems. Managers are advised to consider active restoration measures in areas where recovery is likely to be protracted. [Copyright &y& Elsevier]

Abstract: When considering revegetation strategies for particular restoration projects, data on community composition and structure should, whenever possible, be obtained from reference sites. Revegetation is an important restoration strategy especially since riverbanks that have been cleared of alien vegetation are extremely susceptible to erosion. The presence of lateral zonation in riparian vegetation is well documented: flooding events shape the vegetation on riverbanks and the zones that are inundated annually have different vegetation than those that are inundated interannually. This can be referred to as the demerse ecotope, or Wet Bank, and the emerse ecotope, or Dry Bank, and these zones can also be further subdivided. There is a need for species descriptions from undisturbed riparian zones to guide post-project appraisal and revegetation strategies, especially in areas with high species turnover like the fynbos biome. Braun–Blanquet vegetation belt transects were sampled on five undisturbed rivers that originate in the Hottentots Holland mountain range. Relevés were sampled from as many Wet Bank and Dry Bank subzones as were present in each case. Twenty-six riparian communities were recognized, which were clustered into ten community Groups based on physical bank attributes. The most dominant species for each of these community types have been listed in a synoptic table that can be used for revegetation purposes. It is recommended that revegetation plans make use of a mixture of the listed species, whilst maintaining separation of Wet and Dry Bank species. Prior to species selection, it is necessary to assess the range of riparian habitats available in the project reach. Though revegetation is more expensive than allowing for natural recruitment, recent evidence has shown that recovery of the natural vegetation without intervention may be limited, and not without risks. Revegetation may be a cheaper strategy in the long term, avoiding the maintenance costs that are required to stabilize banks and to remove re-invading alien species. [Copyright &y& Elsevier]

The loss of biodiversity and associated ecosystem services are major threats posed by the spread of alien invasive species. Invasive ants are frequently associated with declines in the diversity of ground-dwelling arthropods but also may affect plants through their attraction to floral nectar and tending of hemipterans. Protea nitida is a tree native to the South African fynbos that hosts a native membracid, Beaufortiana sp., which is tended by ants. Here I compare Argentine ants (Linepithema humile) to native ants in their attraction to P. nitida inflorescences in the presence and absence of the membracid, and their effects on other floral arthropod visitors, seed set, and ovule predation. Argentine ant discovery of inflorescences increased at least 13-fold when membracids were present on the branch, whereas native ant discovery of inflorescences was only doubled by membracid presence at one site in one study year and was unaffected in the other three site-years. Excluding Argentine ants from inflorescences resulted in an increase in several arthropod taxa and potential pollinators; native ant exclusion had no positive effects. Thus the mutualism between Argentine ants and the membracid is facilitating pollinator deterrence by the ants. Though Argentine ants were not associated with a decline in P. nitida seed set or ovule predation, declines in generalist insect pollinators may have ramifications for the 83% of fynbos plants that are insect pollinated. Pitfall traps showed that Argentine ants were not more abundant than native ants in non-invaded sites. Focusing only on abundance on the ground and displacement of ground-dwelling arthropod fauna may lead to an underestimate of the effects of invasive ants on their adopted communities. [ABSTRACT FROM AUTHOR]

Aim It has often been suggested that South Africa's Cape fynbos shrublands, although extremely rich in plant species, are poor in insects, thus representing a notable exception from the broad plant–insect diversity relationship. The aims of this study were to compare the diversity patterns of plant-inhabiting insects in fynbos and the vegetation of three neighbouring biomes (grassland, subtropical thicket, and Nama-karoo), and to test for a general relationship between plant diversity and insect diversity across these biomes. Location South-western to south-eastern South Africa. Methods We conducted seasonal plant surveys and sweep insect sampling in 10 × 10 m plots in the Baviaanskloof Conservation Area (Eastern Cape), where all four biomes occur. We also conducted once-only collections in the core area of each biome. Results Fynbos plots had insect diversity values similar to those of grassland and subtropical thicket (a dense, evergreen and spinescent shrubland with a high abundance of succulents and climbers), and significantly higher than Nama-karoo (an open, semiarid shrubland). A remarkably strong positive relationship was found between plant and insect species richness. Main conclusions Previous generalizations were based on a few insect groups (e.g. butterflies, under-represented in fynbos), but ignored published results on other groups (e.g. galling insects, which are in fact over-represented in this vegetation). We show that, overall, insect diversity in fynbos is comparable to that of neighbouring biomes. Fynbos vegetation does not represent a significant exception from the broad positive relationship between plant diversity and insect diversity. [ABSTRACT FROM AUTHOR]

Of the thirteen ports where HMS Beagle called on its homeward voyage from South America to England, it stayed longer at Simon's Bay (31 May - 18 June 1836) than anywhere else except for the Galapagos Is lands. Yet Charles Robert Darwin, the 27-year-old naturalist on board, practically ignored the Cape in his subsequent publications and many Darwin scholars hardly mention the visit. This silence raises two questions: why did Darwin have so little to say about the Cape, and did the visit in any way contribute to his intellectual development? There are two possible answers. After four and a half years of voyaging, Darwin was stale and found the Cape environment well-studied but uninspiring. At the Cape, secondly, Darwin met Sir John Herschel, the leading British scientist of the day, then cataloguing southern hemisphere stars. Herschel probably directed him to granite outcrops in the Cape Town hinterland, about which Darwin made notes but published little. More importantly, Herschel, through an earlier book and in discussion, made Darwin aware of his ideal of scientific explanation: to look for one comprehensive 'true cause' which could be transferred from one set of phenomena to another. Herschel also showed Darwin his garden of Cape fynbos bulbs, which led the former to speculate on 'the origination of fresh species' as a natural process. For Darwin the Cape must have been an important place of encounter with ideas, some already half formed in his mind and others new, which he developed fully in the years to come. [ABSTRACT FROM AUTHOR]

Afromontane forests in the southern Cape are typically surrounded by fire prone fynbos. Although the impact of fire on fynbos has been extensively studied, little is known about the impact of fire on adjacent forest. Fire swept through a mountain forest in the southern Cape in 1996. Our study indicated that this fire was one of at least two fires that influenced the recent history of this forest; the other fire was probably the great fire of 1869. We consider the latter fire typical of fires that burn mountain forest and suggest a return period for these fires of between a 100 and 200 years. In contrast to the 1869 fire, evidence from our study suggests that the 1996 fire was unprecedented in the recent history of the forest. This fire changed a large proportion of Ocotea bullata in the margin from single stemmed to multistemmed trees and reduced the number of Cyathea capensis in the margin by 68%. Using these species as indicators, we argue that similar fires will reduce the structure and diversity of mountain forests as a whole. The 1996 fire was fuelled by abnormally high fuel loads associated with surrounding pine plantations and mountain fynbos invaded by woody aliens. Given that large areas of mountain fynbos are invaded by woody aliens, that large areas of the southern Cape are afforested and that global climate change is likely to lead to an increase in the conditions favouring intense fires, we consider effective management of Afromontane mountain forests essential. [ABSTRACT FROM AUTHOR]

Leaf anatomy and morphology were studied in 11 tree species growing in an undisturbed forest and the adjoining fynbos for over 50 years. Functional anatomical results suggest that the forest and the fynbos are ecologically distinct. Moreover, leaf anatomy suggests that the foliage is primarily adapted for photosynthesis rather than for control of transpirational water loss. Forest precursor tree species and scrub species exhibit xeromorphy in the fynbos whereas they exhibit mesomorphic features inside the forest. The wide‐ranging species, such as Olea capensis subsp. capensis, simulated the response of the forest precursors, with the cuticle being phenotypically plastic between the forest and the fynbos but not between the stream and non‐stream habitats. Finally, the forest precursors, the scrub species, and the wide‐ranging taxa seem to have anatomical characters which can be modified in the fynbos and therefore allow its colonization by a variety of different species. [ABSTRACT FROM PUBLISHER]