Why do aquatic carnivorous plants prefer growing in dystrophic waters?

Abstract

The majority of aquatic carnivorous plants (ACPS; Aldrovanda, Utricularia) usually grow in shallow dystrophic waters. In these habitats, rootless ACPs usually grow together with rooted aquatic non-carnivorous plants (N-ACPs). Yet species diversity of rooted N-ACPs in dystrophic lakes is relatively poorer than that of abundant ACPs. If generally true, why do rootless ACPs prefer growing in shallow dystrophic waters and why is the occurrence of rooted N-ACPs in these waters limited? These questions are elucidated on the basis of different specific adaptive traits of both functional groups and a different treatment of external habitat factors on both plant groups.