Trait Variability in Bromeliaceae Species from High-Elevation Habitats of the Atlantic Forest: Morphoanatomical and Biochemical Responses to Environmental Factors

The interaction between abiotic factors and plant traits is central to ecological strategies and species distribution, especially in environments with climate variability. It is reflected in morphoanatomical and biochemical traits that influence growth and survival. Widely distributed, species-rich families are models for understanding how environmental filters shape plant traits and foster innovation. Bromeliaceae, a diverse Neotropical family, exemplifies this dynamic, bringing together species with multiple habits (epiphytic, rupicolous, saxicolous, and terrestrial) and remarkable morphological diversity. Given Bromeliaceae significance in the Brazilian Atlantic Forest, particularly in high-elevation regions, we investigated environmental parameters potentially influencing trait variation in three widely distributed species: Aechmea vanhoutteana, Pitcairnia carinata, and Quesnelia kautskyi, occurring in distinct areas within Parque Nacional do Caparaó (MG/ES), Brazil. PCA analyses confirmed that temperature, humidity, and light intensity were the primary filters shaping functional trait space, possibly influencing niche differentiation and species coexistence. Aechmea vanhoutteana exhibits a generalist ecological strategy, thriving across all three life habits with minimal morphoanatomical and biochemical content adjustments. Pitcairnia carinata, confined to rocky outcrops, exhibited notable anatomical specializations likely balancing thermal tolerance and water conservation. Quesnelia kautskyi demonstrated the greatest trait variation, particularly between terrestrial and epiphytic individuals, with humidity emerging as the main driver of anatomical and biochemical differences. While morphological traits were relatively stable across conditions and functioned as “effect traits”, anatomical and biochemical traits acted as “response traits”, adjusting dynamically to environmental stimuli. Altogether, the results highlight that morphoanatomical and biochemical plasticity is critical for ecological performance and persistence in heterogeneous montane landscapes. Furthermore, approaches incorporating multiple traits can offer key insights into how environmental pressures potentially drive plant adaptation, specialization, and evolution in Neotropical ecosystems.