O quanto podemos aprender sobre adaptação de plantas a partir das Asteraceae Bercht. & J.Presl? um estudo nas montanhas do Parque Nacional do Itatiaia, Brasil

Abstract

Altitudinal gradients provide natural models for understanding how environmental variation influences plant communities and offer valuable insights into potential responses to climate change. This study investigated whether leaf anatomical traits of Asteraceae vary along the altitudinal gradient of Itatiaia National Park and whether these variations are associated with distinct ecological strategies. Nine species were sampled across five elevations (1700–2500 m a.s.l.) in the high-altitude grasslands, and quantitative and qualitative leaf anatomical traits were analyzed together with community structure, environmental variables, niche breadth, and phenotypic plasticity using multivariate approaches. Leaf anatomy varied markedly among species, revealing distinct anatomical syndromes and a clear trade-off between stomatal density and stomatal size. Along the gradient, community composition changed progressively, while climatic and edaphic conditions became increasingly differentiated. Temperature and atmospheric moisture emerged as the principal environmental filters, but species did not converge toward a single anatomical solution. Instead, different combinations of anatomical traits, together with differences in niche breadth and phenotypic plasticity, allowed multiple functional strategies to persist under similar environmental conditions. These findings indicate that community assembly results from the interaction between environmental filtering and species-specific functional responses, providing a functional framework for understanding and predicting how tropical high-elevation plant communities may reorganize under future climate change.