Floods reduce the prevalence of exotic plant species within the riparian zone: Evidence from natural floods

Abstract

Questions: Does flooding reduce the prevalence of exotic plant species and promote native riparian plant species? Location: Field study, two regulated lowland rivers, SE Australia. Methods: We used a large flood in spring to test predictions of vegetation response to flooding. We predicted that the species richness of exotic taxa (mostly terrestrial annual/biennial grasses and forbs in the study systems) would be reduced by flooding, while the richness of native riparian species adapted to fluvial disturbance would increase. We surveyed the riparian vegetation at three sites on each of two regulated rivers in the summers before and after a large flood in early spring that inundated all of th..