Biomass density and the relationship between submerged macrophyte biomass and plant growth form

The utility of biomass density (biomass per unit volume) as a quantitative descriptor of the growth form of submerged macrophytes is evaluated and confirmed. Biomass density (BD) is a species specific characteristic which does not appear to be influenced by plant development. Secondly, BD reflects the growth form of the dominant species in the stand, because stands of species with a similar growth form also have similar BD's. Lastly, the BD of submerged macrophyte stands is closely related to the flowering pattern of the dominant species, and has important implications for light capture and light competition with neighbouring plants. Thus, BD should be a useful tool in the quantitative analysis of submerged macrophyte community structure.