Our primary interest lies in understanding the biology of invasions by animals and plants, mainly the interactions between native and invasive communities and their ecosystems. Our secondary interest lies in understanding the trophic interaction in shallow lakes and its effect on the ecosystem state shifts. To address these questions we work mostly with aquatic macrophytes, but have also worked with invertebrates and fish. We like to work at the interface between community ecology and ecosystems ecology and use a variety of methods to ask questions about the forces that shape community interactions, and the effects of these interactions on biodiversity, including field and experimental approaches. Most of our field studies are developed in the large floodplain of the Paraná River and in a large Neotropical reservoir (Itaipú). Our experimental studies include micro and mesocosms as well as in situ experiments.