Effect of clonal growth form on the relative performance of species in experimental communities over time

Abstract

Due to competition for resources, the performance of plant species in communities is modified by traits affecting their efficiency in resource uptake and use. Clonal growth by stolons or rhizomes enables plants to spread laterally and to share resources among interconnected ramets; therefore, clonal growth represents an important trait that likely affects the competitive ability of species. We tested the effect of different clonal growth forms on the relative performance of plant species in communities of the Jena Biodiversity Experiment over a ten-year period. Clonal growth form did not have a significant effect on relative performance in early stages of the communities. Surprisingly, none of the clonal growth forms gained dominance over time, but the species with long rhizomes generally performed slightly better than the other species, particularly in communities of low diversity. The stoloniferous species performed better in communities with a higher proportion of nonclonals, suggesting complementarity of the light exploitation strategies of stoloniferous and nonclonal species. Our results show the importance of clonal growth traits for the competitive abilities of plants in the context of community development, species diversity and community composition, as well as the necessity of distinguishing among different clonal growth forms.