Spatial Complexity Measured at a Multi-Scale in Three Aquatic Plant Species

ABSTRACT

We investigated the hypothesis that available habitat heterogeneity within an aquatic plant bed is scale dependent. A multi-scale approach was used to quantify spatial-complexity at five different scales of resolution in three different aquatic plants species (Cabomba furcata, Najas microcarpa, and Utricularia foliosa) collected from lagoons in the Upper Paraná River floodplain basin, Brazil. The effect of scale upon spatial-complexity was highly significant and interactions between species and scale were also significant, suggesting that habitat heterogeneity was scale dependent and plants contained a species-specific threshold where complexity was highest. Our data represent scale dependent heterogeneity potentially important at mediating biological interactions in aquatic plants and provide a starting point for investigating multi-scale based hypotheses explaining physical and biological interactions among aquatic organisms and vegetated habitat.