Influence of environmental and morphological parameters on the microfauna community present in phytotelmata of a bromeliad in a fragment of Atlantic Forest, southern Brazil

Bromeliads are important epiphytes due to their abundance in the Neotropical region and morphological complexity. Their compact and imbricated leaf bases form water storage cisterns that promote important resources for colonization by several prokaryotic and eukaryotic microorganisms. Due to the lack of knowledge about these environments, the objective of the study was to investigate which physical-chemical and ecological parameters exert effects on the biological richness present in the cisterns of Vriesea platynema. The study was carried out in the Center for Research and Nature Conservation (CPCN – Pró-Mata), in the Serra Geral plateau, northeastern Rio Grande do Sul, Brazil. Active searches were performed for 10 trees with bromeliads fixed at two heights (< 1.5 m and > 2.5 m). For each bromeliad individual, the height in relation to the ground, the diameter and depth of the central cistern, water temperature, number of lateral cisterns and number of adjacent bromeliads, were measured. A total of 23 taxa were identified in the phytotelmata of V. platynema, with Philodina, Lambornella, Paramecium, Tetrahymena and Diptera larvae being the most representative groups. The richness of organisms in the phytotelmata presented a positive correlation with water temperature (p = 0.01), and the number of adjacent bromeliads (p = 0.05), indicating that physicochemical and ecological factors could influence the richness of bromeliad biota