Biogeografia funcional de Kielmeyera Mart. & Zucc (Calophyllaceae) em biomas da América do Sul

Abstract

The use of functional traits is frequently employed to understand species distribution in response to different environmental variables, revealing the functional diversity of plants. Here, we evaluated the variation in functional traits of the genus Kielmeyera, whose species tend to occur in areas with shallow soils, low nutrient availability, and some degree of water limitation. The genus is widely distributed in South America, with its highest predominance in Brazil, within the Cerrado and Atlantic Forest domains. Leaf functional trait data were collected with the aim of building a database for Kielmeyera. Most of the traits were leaf-related, including two morphological traits, seven anatomical traits, and three related to venation; we also recorded the presence of xylopodia in Kielmeyera species. The variation in functional traits among species was analyzed using PCA, in which the set of 27 traits was evaluated considering their life forms and functional diversity metrics. The relationship between traits and environmental variables was assessed through RLQ analysis using a dataset of 20 species of the genus. The species exhibited distinct functional strategies, revealing a functional gradient ranging from dry to moist vegetation types, in which functional traits of Cerrado/Campo rupestre environments contrasted with those of Restinga, while seasonal forest vegetation presented intermediate values. We found low functional richness and high functional divergence, indicating that the genus displays broad functional strategies, especially in subshrub and small-tree life forms, reflecting their wider distribution within Kielmeyera. The presence of xylopodia was associated with traits related to drought and water-use efficiency, reinforcing the importance of specialized adaptive strategies in the genus.