Macrophyte functional groups elucidate the relative role of environmental and spatial factors on species richness and assemblage structure
Abstract
We evaluated the relative importance of environmental and spatial factors on species richness and assemblage structure of macrophytes in 29 coastal wetlands in southern Brazil. We used variation partitioning on total assemblage and three functional groups (emergent, floating, and submerged) and predicted that the relative importance of environment would be greater than that of space for all groups. Further, we predicted that both environment and space would show greater relative importance for floating and submerged than for emergent species, since the first ones depend more on local characteristics and on hydrocoric and zoocoric dispersal, while emergent species are less dependent on local characteristics and disperse mostly by wind. Variation in species richness was partly explained only for floating macrophytes by the environmental fraction. Regarding assemblage structure, environmental variables were more important for floating species and spatial variables for submerged species than for emergent ones and total assemblage. Further, while floating species were structured only by local environmental variables, emergent species were influenced by climatic environmental variables. These results revealed different patterns among macrophyte functional groups in wetlands, highlighting the importance of accounting for ecological differences to further advance the understanding of the relative role of predictors to metacommunity structure.
Claudio R. T. Trindade
PhD student
