Abstract Mortality of epiphytic bromeliads could increase due to dense independent factors, reducing their diversity and contribution to ecosystem functioning. For seven months, we assessed the effect of precipitation and a mechanical factor on the fall of bromeliads, including their richness, abundance, population size, and traits. Our study was conducted in a protected area of Colombia’s Andean tropical forest, where we collected individual-fallen and branch-fallen bromeliads. We then established their taxonomical identity, developmental stage, phytosanitary status, and morphological traits. We examined the relationship between the canopy bromeliad community and fallen bromeliads, and the effect of precipitation and a mechanical factor (the diameter of branches with bromeliads) on fallen bromeliads. The richness and abundance of fallen bromeliads increased with the precipitation, branch diameter, and abundance of canopy bromeliads. Precipitation is the main factor influencing bromeliad fall, affecting juvenile bromeliads more proportionally. Precipitation increases the likelihood of detachment of the bromeliad through an increase in the bromeliad weight, less resistance to heavy raindrops by the root system, and water accumulation in the tree’s bark, and desorption by roots. Although a bromeliad is typically considered dead when it falls, our findings indicate that fallen bromeliads are predominantly juvenile individuals in good phytosanitary condition. This suggests that bromeliad conservation strategies should prioritize the recovery of fallen bromeliads, especially in areas with high risks of local extinction.

Abstract Chronosequences provide space-for-time substitutions to study ecological succession and guide restoration efforts. We evaluated seed rain dynamics across a tropical forest chronosequence in the lowland mountain landscape of Caquetá, Colombia, using monthly seed trap data collected from September 2017 to August 2018 in 18 plots (50 × 50 m) classified into early-secondary, intermediate-secondary, and old-growth forest. Seed morphospecies richness and mean seed mass increased with stand age, while total seed abundance declined, suggesting a transition from small-seeded pioneer species to larger-seeded, late-successional species. Despite differences in richness and abundance, species composition did not differ among stand age groups, likely due to the limitations of morphospecies identification. Seed rain positively correlated with precipitation with a lag time of 3 months, suggesting that heavy rainfall is a prerequisite for fruit production. Seed rain peaks were dominated by Eugenia sp. and Piptocoma discolor , the latter contributing most seeds in early- and intermediate-secondary forests. Correlations between morphospecies richness and seed abundance with basal area (m 2 /ha), species richness, and species diversity are likely explained by resources associated with structural variables (e.g., fruit abundance, canopy cover, and microhabitat diversity) that influence seed disperser behavior. Additionally, successional stage may play a role, as older or more structurally complex forests tend to support more plant species that may contribute to higher seed rain diversity and abundance. Early-secondary forests in this landscape are unlikely to be dispersal-limited, indicating potential for unassisted restoration, though isolated patches may require connectivity interventions such as plantings or living fences to overcome seed input constraints. Further studies are required to evaluate disperser movements across the fragmented landscape as well as plant recruitment, prior to making recommendations on ecological intervention strategies.

The Cerrado biome encompasses different vegetation types, ranging from savanna-like vegetation to forest-like vegetation, represented by a vegetational continuum from Cerrado Típico, Cerrado Denso and Cerradão, respectively. Nevertheless, there are still uncertainties on whether these different vegetation types do not only differ in their vegetation structure, but also in their species compositions. Based on vegetation surveys from 167 plots in the central Brazilian Cerrado, we addressed two questions: (i) How variable is the vegetation structure and species between different Cerrado vegetation types? Second, (ii) how strongly are vegetation structure and species composition linked? To answer these questions, we performed hierarchical clustering for species composition and vegetation structure. Our results showed that for species composition only 18% of the variance was explained by hierarchical clustering, while for vegetation structure 82% of variance was explained. Additionally, there was a significant difference in the structure metrics between clusters, showing that it is possible to clearly identify different Cerrado vegetation types based on vegetation structures, but not by species composition. Finally, we suggest that trait plasticity in Cerrado trees should drive structural differences among vegetation types, which could be the focus of future studies.