摘要：Highlights•Invasion byL. camaraat high cover condition significantly decreased native species diversity and composition.•The impacts ofL. camarainvasion on native species is cover dependent.•The presence ofL. camaraat different cover conditions is likely to transform the natural ecosystem, therefore management interventions (removal/clearing) to reduce invasion extent should be implemented.AbstractAlthough the effects of invasive alien plants on natural ecosystems are widely acknowledged, the effects of specific plant species can be context dependent. The study examined changes in native vegetation diversity and composition followingLantana camarainvasion at different cover conditions in the Vhembe Biosphere Reserve, Limpopo Province of South Africa. Using a comparative approach, native vegetation diversity, cover, and composition were compared inL. camarahigh and low cover and uninvaded conditions, on three replicated sites, each with five 10 × 10 m plots. Results show that vegetation diversity (species richness, Shannon-Wiener, and evenness index) were significantly higher in the uninvaded condition than in theL. camarahigh and low invasion conditions. Species relative cover was significantly higher in uninvaded condition than inL. camarahigh and low invasion conditions, though it decreased gradually along the invasion cover gradient for trees and shrubs as well as forbs. Analysis of similarities showed significant separations in vegetation composition among the three invasion conditions for all the growth forms, with most woody alien plants, e.g.Acacia mearnsii, Rubus rigidus, andCaesalpinia decapetalabeing associated withL. camarahigh and low invasion conditions. The study concludes that invasion byL. camarawas associated with changes in native vegetation diversity, cover, and composition, with observed changes being more visible underL. camarahigh as compared to low invasion condition. The presence ofL. camaraat high cover condition significantly decreased native species diversity and composition, an indication that impacts ofL. camarainvasion are cover dependent. From a management standpoint, the study suggests the removal ofL. camara, however such removal should consider protecting the co-occurring native species. This study offers a baseline for further research to determine mechanisms responsible for native vegetation change associated withL. camarainvasion.
关键词：KeywordsBiological invasionsCommunity level effectsDeclining species compositionManagementSpecies diversity
