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Fire plays a pivotal role in driving ecological shifts between Mediterranean‐type vegetation and subtropical ecosystems in South Africa. This study investigates long‐term environmental dynamics and ecological regime changes at the Mediterranean‐type vegetation /subtropical boundary using a 6000‐year palaeoecological sequence from the Baviaanskloof – a region of South Africa characterized by high levels of biodiversity and climate dynamism. Combining fossil pollen and microcharcoal data from a rock hyrax Procavia capensis midden, we analyse vegetation responses to environmental changes. Our findings reveal that Mediterranean‐type vegetation resilience prevailed until ca 2800 cal year BP when a major fire event triggered a transition to a subtropical thicket‐dominated environment. This abrupt ecological turnover underscores the significance of fire as a major driver of vegetation change at the Mediterranean‐type vegetation /subtropical boundary. Our study emphasizes the vulnerability of Mediterranean‐type vegetation ecosystems to global environmental change, suggesting potential implications for similar biome boundaries worldwide. By integrating multi‐proxy palaeoecological evidence, we gain insights into the resilience and vulnerability of these ecosystems, aiding in understanding future responses to climate change scenarios. [ABSTRACT FROM AUTHOR]

Plantations, and associated invasions, of exotic Pinus trees occur extensively in the southern hemisphere, threatening the persistence of biodiverse Mediterranean‐climate vegetation. Large‐scale decommissioning of such plantations in the eastern Cape Floristic Region (South Africa) enabled a wide‐ranging study showing successful passive restoration of fynbos vegetation after afforestation. Using a paired study design, we compared the diversity, and floristic and growth‐form composition of post‐fire recovering fynbos in former plantations with that in recently burnt neighboring fynbos in a natural state within the Garden Route National Park. The fynbos of the study area showed good autogenic recovery after several decades of pine afforestation and a fire subsequent to the clearcutting of these trees. On average, native plant abundance and species richness (particularly of shrubs) were significantly lower, and non‐native plant species richness significantly higher, in former plantation areas than in natural fynbos, but these differences were small. Species diversity (Shannon–Wiener index) did not differ significantly between the two vegetation states. The former plantations harbored 91% of the number of native species that the natural fynbos had, while the similarity of the two floras was 65%. Non‐metric multidimensional scaling ordination and multivariate generalized linear models accordingly showed no clear distinction in community composition between the two vegetation states. We concluded that the restoration potential of the montane grassy fynbos in the study area is superior to that previously documented in montane proteoid fynbos, and that fire and invasive alien plant control after clearcutting of the plantations is essential to promote fynbos restoration. [ABSTRACT FROM AUTHOR]

Background: The subtropical dune thicket (hereafter "dune thicket") of the Cape Floristic Region experiences a wide range of fire exposure throughout the landscape, unlike other dry rainforest formations that rarely experience fire. We sought to determine how fire exposure influences species composition and the architectural composition of dune thicket. Methods: We used multivariate analysis and diversity indices based on cover abundance of species to describe the species composition, architectural guild composition and structure of dune thicket sites subject to different levels of fire exposure, namely low (fire return interval of >100 years), moderate (fire return interval of 50-100 years), and high (fire return interval of 10-50 years). Results: The diversity, cover abundance and architectural guild cover abundance of dune thicket canopy species were strongly influenced by the level of fire exposure such that each level was associated with a well-circumscribed vegetation unit. Dune thickets subject to low fire exposure comprises a floristically distinct, low forest characterized by shrubs with one-to-few upright stems (ca. 4-8 m tall) and a relatively small canopy spread (vertical growers). Of the 25 species in this unit, 40% were restricted to it. Dune thickets subject to moderate fire exposure had the highest abundance of lateral spreaders, which are multi-stemmed (ca. 3-6 m tall) species with a large canopy spread and lower stature than vertical growers. None of the 17 species found in this unit was restricted to it. Dune thickets subject to high fire exposure had the highest abundance of hedge-forming shrubs, these being low shrubs (ca. 0.6-1.4 m tall), with numerous shoots arising from an extensive system of below-ground stems. Of the 20 species in this unit, 40% were restricted to it. Multivariate analysis identified three floristic units corresponding to the three fire exposure regimes. Compositional structure, in terms of species and architectural guilds, was most distinctive for dune thickets subject to high and low fire exposure, while the dune thicket subject to moderate fire exposure showed greatest compositional overlap with the other units. Conclusion: Fire exposure profoundly influenced the composition and structure of dune thicket canopy species in the Cape Floristic Region. In the prolonged absence of fire, the thicket is invaded by vertical-growing species that overtop and outcompete the multi-stemmed, laterally-spreading shrubs that dominate this community. Regular exposure to fire selects for traits that enable thicket species to rapidly compete for canopy cover post-fire via the prolific production of resprouts from basal buds below- and above-ground. The trade-off is that plant height is constrained, as proportionately more resources are allocated to below-ground biomass. [ABSTRACT FROM AUTHOR]

• The suitability of road verges as habitats for fynbos plants is poorly understood. • We investigate pollination of ornithophilous Erica glandulosa in road verges. • Fewer flowers were visited by birds closer to the road. • Fewer flowers were visited in road verges next to transformed land. • On average, 20–30% of flowers found within 10 m of the road were visited by birds. Road verges can provide important habitats for plants, especially in transformed landscapes. However, roads and their associated traffic have several adverse impacts on ecosystems that can disrupt vital ecological processes, including pollination. In transformed landscapes, the negative effects of roads on pollination might be complemented by impacts of large-scale habitat modification. In these landscapes, road verge populations of plants that rely on pollinators could thus be at risk of pollination failure. This study investigates the pollination of a reseeding, bird-pollinated shrub, Erica glandulosa , in road verges of a fragmented and transformed rural landscape in the southeastern Cape Floristic Region. We test for road impacts on pollination by comparing number of ruptured anther rings – a proxy for pollination – in fynbos vegetation fragments at different distances from the road (0–10, 20–30 and 40–50 m). We also test whether different land-cover types (intact fynbos, alien thickets and rangelands/pastures) next to road verges influence the number of ruptured anther rings. After controlling for robbing rate and plant density, fewer flowers were pollinated near the road (0–10 m) than farther away (beyond 20 m), and fewer flowers were pollinated where road verges occurred next to alien thickets or pastures/rangelands compared to intact fynbos. However, bird pollinators were not excluded in road verges: on average, ca. 20–30% of flowers occurring within 10 m of the road were still visited by birds. While we expect the reduced pollination rate to have a negative effect on the fecundity of road-verge plants, it remains to be tested whether the pollination rate observed in verges is sufficient to sustain populations of bird-pollinated, seed-dependent plants. [ABSTRACT FROM AUTHOR]

Aim: South Africa's subtropical dune thicket represents an interesting case for investigating plant architecture since, unlike most other dry rain forest formations, dune thicket is subject to regular fire. We asked the following questions: (a) what are the different architectural guilds amongst subtropical dune thicket species in mature, closed canopy stands; (b) what are the architectural guilds of the same species but in the early stages of resprouting post fire; (c) do pre‐fire guilds predict post‐fire guilds; (d) what is the significance of our findings for explaining temporal (post‐fire) and spatial patterns of subtropical dune thicket species? Location: Cape St Francis, southeastern Cape Floristic Region, South Africa. Methods: We used univariate and multivariate methods to identify architectural guilds amongst 11 commonly occurring dune thicket species in closed (light‐limited), long unburnt vegetation and in recently burnt stands where vegetative regrowth (sprouts) is exposed to light. Results: We found three distinct architectural guilds in unburnt subtropical dune thicket, namely hedge formers, lateral spreaders and vertical growers. In burnt thicket we also identified three resprouting architectures, namely weak resprouters, moderate resprouters and strong resprouters. There was no strong congruence between the unburnt and resprouting architectures. Conclusion: Based on the ecologies of each guild, certain expectations originated from the results of the study. We expect frequently burnt landscapes to be dominated by strongly resprouting hedge formers and lateral spreaders, infrequently burnt landscapes to be dominated by strongly resprouting lateral spreaders, and fire‐free landscapes to be dominated by weakly resprouting vertical growers. [ABSTRACT FROM AUTHOR]

Premise of research. Road verges are important refugia for plants, particularly rare or threatened species, in transformed landscapes. However, traffic disturbance could disrupt plant-pollinator interactions and so undermine the conservation value of road verges. Here we investigate the indirect road impact on the pollination and fecundity of a highly threatened shrub, Cyclopia pubescens , through changes in insect pollinator behavior. Methodology. We compared pollinator activity (visitor frequency and number of flowers visited per pollinator) and plant reproductive output (fruit set and seed set) at three distances from a highway while considering the effects of C. pubescens plant density and floral display size (number of synflorescences per plant and number of flowers per synflorescence) on pollinator activity. Pivotal results. The pollinator, Xylocopa flavorufa , and other floral visitors (Xylocopa caffra and Apis mellifera) were most abundant next to the road, while individual pollinators visited more flowers next to the road compared with farther away. Pollinator activity was highest near the road in response to larger C. pubescens floral displays in this zone compared with farther away, yet pollinator visitation rate, fruit set, and seed set were comparable at all distances from the road. Conclusions. While we found no evidence of a road effect on the reproductive output of C. pubescens , the larger floral displays of plants occurring near the road appear to be attractive enough to pollinators to counteract traffic disturbance—this bodes well for the viability of road verges as habitats for entomophilous plants. [ABSTRACT FROM AUTHOR]

In Mediterranean-Climate Ecosystems (MCEs), Holocene coastal dunes comprise small, fragmented and dynamic features which have nutritionally imbalanced and excessively drained, droughty, sandy soils. These characteristics, along with summer drought and salt-laden winds, pose many challenges for plant colonization and persistence. Consequently, MCE dune floras are likely to be distinctive with a high proportion of habitat specialists and strong convergence in growth form mixes. Very little research has compared the species traits of dune floras within and across MCEs. This paper contributes to filling that gap. Here, we analyze the taxonomic, biological and geographical traits for all 402 species in a flora from a dune landscape (Cape St Francis) in the southeastern Cape Floristic Region (CFR) and compare patterns with the trait profiles of other dune floras at a regional (CFR) and global (MCE) scale. Within the CFR, the southeastern (all-year-rainfall) flora at Cape St Francis had a similar trait profile to western (winter-rainfall) dune floras, except for having a lower representation of species belonging to CFR-endemic clades, and higher number of species associated with tropical lineages. The St Francis flora, in common with other CFR and MCE floras, was dominated by members of the Asteraceae, Fabaceae and Poaceae. Some 40% of the St Francis flora was endemic to the CFR, typical of the high rate of MCE-level endemism elsewhere in the CFR, and in other MCEs. About 30% of the flora was confined to calcareous sand, a value typical for many other MCE sites. The St Francis flora, as well as other CFR dune floras, differs from those of other MCEs by having many species associated with shrubby lineages, and by the relatively high incidence of species associated with tropical lineages. The growth form profile of the St Francis and other CFR floras shows strongest similarity with that of Australian MCE dunes in that in both regions, evergreen hemicryptophytes and shrubs share dominance, and annuals are floristically and ecologically subordinate. The least similar of MCEs to the St Francis trait profile is the Mediterranean Basin where annuals are the most frequent growth form while shrubs are subordinate. California and Chile dune floras appear to occupy an intermediate position, in terms of growth form mix, between the Cape and Australia on the one hand, where dune floras have retained features typical of nutrient-poor soils, and the Mediterranean Basin, where dwarf, deciduous shrubs and annuals dominate the life form spectrum. All MCE dunes are threatened by alien plants, infrastructure development, tourism demands and rising sea levels. The high incidence of species of conservation concern in CFR dune floras underestimates the exponentially increasing threats to their habitats, which are already historically at a much-reduced extent. All remaining coastal dune habitat in the CFR, and probably in other MCEs, should be conserved in their entirety. [ABSTRACT FROM AUTHOR]