Phytotelm functional groups response to different habitats and years

ALVAREZ ARNESI E.; TESSORE A.; MONTERO G.A.; ASMUS J.; BARBERIS, I. M.; FREIRE, RODRIGO; KLEKAILO G; BARISÓN C.

Workshop; The Bromeliad Working Group 2020 Virtual Conference; 2020

The Bromeliad Working Group

The Gran Chaco Phytogeographic region is located in South America and there, bromeliads form dense colonies in the understory of xerophytic forests. The Chaco xerophytic forests are the austral limit of the distribution of tank bromeliads, and Aechmea distichantha is the only tank bromeliad species there. In these forests, there are open sunny habitats and closed shaded habitats (e.g. different canopy openness), and Aechmea distichantha plants present phenotypic plasticity associated with this heterogeneity. There are large differences in rainfall between years. We performed 4-year invertebrate censuses including three different habitats and a plant size gradient. Each year we sampled 10 plants at each habitat. Years differed in the total amount of rainfall. The most important group of predators (Piercers) of our assemblages was more abundant in humid years in bigger plants independently of the habitat. We also found that our most important group of detritivores (Scrapers-mainly one species) was more abundant in bigger plants and found no clear effects of habitats and years. Finally, we found that the abundance of filter feeders, diminished in dry years; individuals being associated with open areas where plants have bigger tanks and effectively held more water.