Clonal mobility and its implications for spatio-temporal patterns of plant communities: what do we need to know next?

Abstract

Patterns of clonal growth and their controls on the level of individuals have been studied thoroughly, but little is known about the actual clonal mobility of plant individuals in vegetation and about its role in generating vegetation patterns and influencing species coexistence. Current evidence shows that communities are composed of spatially nonmobile ‘matrix-forming species’ and mobile ‘inter-matrix’ species, while local between-species variation in clonal mobility has been shown to be positively correlated to small-scale richness. We identify two major gaps in the knowledge. (1) Clonal mobility has a strong species-specific component, but the existing information is mainly qualitative and describes the potential mobility of species the best. Also, species may respond by their clonal growth in a plastic way to some environmental stimuli, such as neighbors or abiotic environment, but this data comes almost exclusively from artificial conditions. We know very little of the actual spatial mobility of clonal plant individuals in the field and of the factors that determine it. (2) Theoretical research indicates that localized dispersal plays prime role in determination of community structure. While clonal mobility shares many important features with the seed dispersal, it also shows important differences to it, such as in dispersal kernel (non-monotonic in clonal dispersal), role of microsite limitation, and role of plasticity. We have little information how systematic are these differences, and whether these differences in dispersal can play any role in shaping community dynamics. We conclude that clonal mobility has an important role in structuring plant communities in a small scale and propose further studies to address specific mechanisms, as well as community context of evolution of clonality.