Protocols for Restoration Based on Recruitment Dynamics, Community Structure, and Ecosystem Function: Perspectives from South African Fynbos

Abstract

AbstractSouth African fynbos ecosystems are under threat from alien plant invasions and transformations to alternative land uses. If large‐scale habitat loss and species extinction are to be halted, restoration actions are urgently required. We postulate that by adopting an approach in which an understanding of community and ecosystem dynamics is applied to restoration practices, protocols can be developed which will lead to more efficient restoration. This understanding is based on a review of the relevant ecological literature, focusing on recruitment dynamics, community structure, and ecosystem function, which are particularly relevant to restoration. We develop a conceptual framework for restoration and apply our protocols to a case study area on the Cape Peninsula. Before ecological restoration can begin, the cause of transformation must first be removed or ameliorated. The next step is to ensure that the important ecological processes are functioning. We contend that a fully functioning community requires a good balance of the major growth‐form, regeneration, and nutrient acquisition guilds. Fire is the natural disturbance event initiating recruitment in fynbos. It is, therefore, essential to either burn a site or provide fire‐related germination cues in order to stimulate recruitment. Where guilds are under‐represented, corrective reintroductions will further improve the long‐term resilience of the restored community. Many taxa have persistent soil‐stored seed banks, so it is important to conserve topsoil and optimize use of this local species pool. Seed dispersal distances are generally very short, and in highly transformed sites it will be necessary to reintroduce seed of the major guilds in order to restore community structure and functioning. Post‐fire succession in fynbos begins with the full complement of species; species gradually die out from the vegetation according to their respective life spans. In order to stimulate germination and promote successful establishment, it is important to sow seed after fire or site clearing in late summer or autumn. Introducing seed or plants at a later stage in the succession is very likely to fail. Because of the localized distributions of many taxa, extreme care must be taken when selecting species for reintroduction if local gene pools are to be conserved.