Establishment limitation may be more important than species dispersal: insights from dry grasslands and old-fields
Abstract
QuestionsOld-fields and their succession often played crucial role in dynamics of species-rich semi-natural grasslands. Our objective was to assess whether colonization of old-fields by grassland species is limited by the availability of seeds, dispersal abilities, habitat requirements of the species or biotic interactions.
In particular, we asked following questions: (1) What are the main constrains limiting frequency of grassland species in old-fields? (2) Is frequency in source habitat (grasslands) and target habitat (old-fields) limited by the same factors/processes? And (3) how the results and their interpretation change after considering species phylogeny? LocationOld-fields and grasslands in northern Bohemia, Czech Republic, Europe. MethodsFrequency in old-fields and grasslands of 29 plant species was related to a set of species characteristics representing source, dispersal, abiotic and biotic limitation using phylogenetic regression.
ResultsSpecies frequency in old-fields was significantly correlated with frequency in grasslands. In general, habitat (biotic and abiotic) limitation was more important for frequency in both habitat types without phylogenetic correction.
Specifically, frequency in both habitat types was mostly limited by soil preference and in grasslands also by niche width. Old-fields were relatively more colonized by species with better competitiveness.
Phylogenetic signal was not detected during phylogenetic regression. ConclusionsTo preserve high diversity in grasslands, the effort should be directed towards maintenance of soil quality (minimize the use of fertilizers, pesticides and heavy machinery).
Colonization of old-fields could be enhanced by reduction of competitive species by introduction of traditional management (e.g., mowing or grazing).