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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]

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]

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]