Geographic patterns of tree dispersal modes in Amazonia and their ecological correlates

Aim To investigate the geographic patterns and ecological correlates in distribution of most common tree dispersal modes Amazonia (endozoochory, synzoochory, anemochory hydrochory). We examined if proportional abundance these could be explained by availability agents (disperser-availability hypothesis) and/or resources for constructing zoochorous fruits (resource-availability hypothesis). Time period Tree-inventory plots established between 1934 2019. Major taxa studied Trees with a diameter at breast height (DBH) ≥ 9.55 cm. Location Amazonia, here defined as lowland rain forests Amazon River basin Guiana Shield. Methods assigned to total 5433 species morphospecies within 1877 tree-inventory across terra-firme, seasonally flooded, permanently flooded forests. investigated modes. performed an abundance-weighted mean pairwise distance (MPD) test fit generalized linear models (GLMs) explain Results Anemochory was significantly, positively associated annual wind speed, hydrochory significantly higher Dispersal did not consistently show significant associations fruits. A lower dissimilarity modes, resulting from dominance endozoochory, occurred terra-firme (excluding podzols) compared Main conclusions The disperser-availability hypothesis well supported abiotic (anemochory seems unlikely explanation Amazonia. association frugivores zoochory requires further research, recruitment only depends on vectors but also conditions that favour or limit seedling forest types.