Fire frequency effects in bud bank size and belowground organs in a South African savanna

Abstract

Savannas are biomes covering around 20% of the global area, mostly tropical, where one-fifth of the world population live and get their resources from and are characterized by high herbaceous species richness and endemism, and unique species composition, where several species, in order to survive to fires and grazing, have developed specialized underground structures that enable them to resprout repeatedly. This resprout ability is the most important regeneration strategy, ensuring the persistence of the population under regular disturbances, and is associated with the development, protection, and resourcing of a viable bud bank, which comprises all buds present in a plant that can be potentially used for vegetative regeneration. In order to understand savanna resistance and resiliency and the different strategies of regeneration of plants in flammable ecosystems, we intend to perform a global comparison among the tropical savannas, to understand how disturbances history impacts the bud bank and belowground structures. We aim to assess the bud bank size and belowground organs diversity in a South African savanna, with the purpose of raising functional traits and relating them to vegetation responses after fire events. The study will be conducted in the South African Lowveld Savanna Bioregion, the physiognomy that is equivalent to the Brazilian savanna, across different treatments of fire. With this work, we hope to provide important information about the resilience of these formations, since the characterization of the regeneration potential will allow a better understanding of the community in tropical savannas.