The model system

The microbial-faunal food web inhabiting water-filled bromeliads is especially amenable to studies of aquatic-terrestrial interactions, food web structure, and ecosystem function, because it is small in size, can be exhaustively sampled, and because it is naturally replicated in neotropical forests.

Rainwater-filled leaf axils of the tank-bromeliad Aechmea aquilega. Credit: Bruno Corbara.

In Neotropical forests, a substantial fraction of the freshwater available is impounded within the rosettes of tank-bromeliads (Bromeliaceae). Bromeliads are flowering plants represented by some 3140 species. The rosettes of bromeliads form wells that collect rainwater and leaf litter, and provide a habitat for aquatic organisms ranging from prokaryotes to invertebrates. The detritus constitutes a source of nutrients for the aquatic food web, as well as for the plant itself. Incoming litter is reduced by invertebrate chewers, then small particles of organic matter and faeces are washed into the plant pools, where particulate organic matter is further processed in the gut of invertebrate collectors and filterers, and utilized by bacteria and other microorganisms. This miniature ecosystem has been studied throughout its range, and is viewed by ecologists as a model system for testing ecological theory. 

A selection of bromeliad inhabitants

This project is part of the activities of the Bromeliad Working Group