Post-fire regeneration in a sand plain lowland fynbos community

The density and species richness of plants with different regenerative strategies and life forms were measured in a sand plain lowland fynbos community during the first year after a late spring fire. Seedling dynamics, distributions and germination depths were assessed. The dominance of seed regenerating species (93.2% of individuals, 58.0% of species) differs from that reported for other fynbos communities. Species richness was similar to that in unburnt vegetation. However, only about 41 % of species were common to pre- and post-fire stands. Post-fire plant distributions were contagious and independent of seed size or dispersal mode. In the vicinity of burnt remnants of invasive alien acacias, the density and species richness of indigenous seeding perennials and ephemerals were reduced. Seedling production and mortalities in seeders and sprouters were similar. Both alien and indigenous seeding perennials exhibited an approximate 40% seedling mortality during the first post-fire year. Seed size was an important factor affecting seedling establishment levels in the post-fire environment. Seeding perennials with large, mainly myrmecochorous seeds emerged sooner after fire and from greater depths than those with small seeds. Their average seedling production was twice that of perennials with small seeds. Die bevolkingsdigtheid en spesierykheid van plante met verskillende regeneratiewe strategieë en lewensvorme is gedurende die eerste jaar van die na-brandse herstel van die plantegroei in ’n sandvlakte-laagland-fynbos-gemeenskap gemeet. Saailing-aanwerwingspatrone, -verspreiding, en -ontkiemingdieptes is vasgestel. Die oorheersing van plante wat deur middel van saad-voortplant (93.2% van indiwidue, 58.0% van spesies) verskil van dit wat vir ander fynbos-gemeenskappe gerapporteer is. Spesierykheid was soortgelyk aan dié van ongebrande plantegroei. Dog is slegs ongeveer 41 % van die spesies gevind in beide die voor- en na-brand-gemeenskappe. Verspreiding van saailinge en herspruitende plante na die brand was klompsgewys en onafhanklik van saadgrootte of verspreidingsmeganismes. Daar was ’n vermindering in beide die bevolkingsdigthede en spesierykheid van inheemse efemere en meerjariges, wat deur middel van saad voortplant, wat in die nabyheid van gebrande uitheemse akasias geleë is. Saailingproduksie en sterftes in plante wat van saad voortplant en dié wat uitloop is soortgelyk. Ongeveer 40% van saailinge van beide uitheemse en inheemse meerjariges wat deur middel van saad voortplant, het gedurende die eerste jaar na die brand gesterf. Saadgrootte was ’n belangrike faktor wat ’n invloed gehad het op die vestiging van saailinge na die brand. Saadvormende meerjariges met groot sade wat hoofsaaklik deur miere versprei word, het vroeg na die brand, en van groter dieptes, opgekom, met ’n gemiddelde van twee maal soveel saailinge as dié van meerjariges met klein sade.