Life strategy systems of xerothermic grasslands – mechanisms of reproduction and colonization within Stipetum capillatae s.l. and Adonido – Brachypodietum pinnati

Abstract

AbstractLife strategy systems of two xerothermic grassland types (Stipetum capillatae s.l., Adonido‐Brachypodietum pinnati) were studied. Five different life strategies are established. A detailed weighted analysis based on the Mean group quantity fraction shows that mainly the community‐specific soil water conditions effect a different significance of predominant colonization and reproduction mechanisms.Within both communities, Perennial stayers of hemicryptophytic life form are best adapted to this habitat. The most important life strategy within the summer‐dry Stipetum capillatae s.l. is that of Perennial stayers with long‐ and short‐range dispersal, with sexual reproduction (PTEs). Site colonization and maintenance takes place through generative, long‐ and short‐range dispersed diaspores, with clonal reproduction having a lower significance.By contrast, within Adonido‐Brachypodietum pinnati characterized by more moderate water conditions, Perennial stayers with long‐ and short‐range dispersal, with clonal reproduction (PTEcl) clearly dominate. Habitat is maintained by vegetative dispersal, and generative diaspores are produced infrequently.Within the grassland communities, there is a strong tendency towards short‐range dispersal. Yet, within Stipetum capillatae, polychorous species characterized by additional adaptations of epizoochorous long‐range dispersal, are biologically significant as well. From the results of the present analysis, different measures of habitat conservation can be derived.