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Question: Which species are successful colonisers of disturbed sites; species adapted to seed dispersal, resistance to abiotic stress, or competition ability? Are successful adaptations for colonisation shared by phylogenetically related species? Location: Czech Republic, Central Europe. Methods: We used two indices of plant species' colonisation ability (developed from an extensive dataset of dated successional series for 1,531 plant species of the Czech Republic): index of colonisation potential (ICP), which is corrected for mass effect (species' frequency in the landscape acquired from Czech National Phytosociological Database, accounting for more common colonisation events of frequent species), and index of colonisation success (ICS), which is solely based on actual species frequencies in disturbed habitats. We also used preferences for successional age (median of age of sites that species had colonised). We correlated these indices with plant functional traits for three functional groups (woody species, non‐woody perennial polycarpic, and non‐woody monocarpic species) either considering the phylogenetic history of a species or not. Results: Woody species were the best colonisers and had the highest preferences for late‐successional stages. Non‐woody monocarpic species had a higher ICP than polycarpic species while their ICS were comparable. The best predictor of colonisation ability of both monocarpic and polycarpic non‐woody species was canopy height, indicating importance of competition. Other successful colonisers were species with seed traits promoting dispersal (low seed mass or low seed terminal velocity). We did not find traits suitable for adverse biotic conditions (high specific leaf area, SLA), low canopy height) to be important. Successional age preference of species was indicated mainly by seed traits (seed mass, seed longevity), which highly corresponded with species' phylogenetic history. Conclusions: Colonisation of disturbed sites is limited by seed dispersal and competitive interactions rather than an adverse abiotic environment. [ABSTRACT FROM AUTHOR]

Questions: Dispersal is important for the formation of biodiversity patterns. However, studying dispersal is difficult, particularly in established communities. We examined local dispersal processes in the forest herbaceous layer by looking at the abundance of plants in the neighbourhood of the surveyed plots and using dispersal traits and fecundity‐related attributes. Location: Thermophilous oakwood in south Moravia, Czech Republic. Methods: We collected plant community and environmental data from 2 m × 2 m plots nested in a 5 m × 5 m square grid, covering 0.36 hectares of temperate forest. We created binomial generalised linear models of species occurrence in the 2 m × 2 m plots, using species frequencies in four adjacent 5 m × 5 m plots (plot neighbourhood) and environmental data, to account for dependence caused by habitat factors. We analysed the relationships between neighbourhood effects and species attributes using linear regression. Results: Approximately one third of species had a stronger association to neighbourhood alone than to local environment factors. For the remaining species, there was a large joint effect of neighbourhood and environment. However, the link between dispersal traits and the neighbourhood effect was weak. The trait analyses showed that plumed appendages were negatively correlated to neighbourhood effects, whereas possession of elongated appendages, high terminal velocity, clonal spread and absence of seed appendages exhibited insignificant positive relationships to the neighbourhood. Conclusions: At the scale of metres, the distributional patterns of forest herbs cannot be solely associated with dispersal. The reasons could be methodological: our data contain a limited set of species with mostly database‐derived attributes. However, there may also be ecological mechanisms involved. The spatial distribution of plants could be modified by limited seed production and further reshaped by extinctions during earlier ontogenetic stages. [ABSTRACT FROM AUTHOR]

Understanding similarities and differences in population dynamics of closely related species is a key prerequisite in attempts to apply knowledge obtained in one species to another species, e.g., for the purpose of predicting future fate of populations of various rare species. It can be expected that species will have similar population dynamics if they are closely related and share similar habitats. Contrasting population sizes and distribution patterns may, however, indicate that the population dynamics will be different. To understand similarities and differences in population dynamics of closely related species, I studied demography of two congeneric endangered species, Linum flavum and L. tenuifolium co-occurring in dry grasslands. Linum flavum occurs with a lower number of large populations, while L. tenuifolium occurs as a large number of small populations. The results showed that L. flavum had higher population growth rates, relied more on survival and growth and its populations were more persistent. In contrast, populations of L. tenuifolium were more prone to extinction and frequent recolonisation was necessary for their survival in the landscape. This was in accordance with observed population sizes of the two species and their frequency in the landscape. The results indicate that despite being closely related and occurring in the same habitat types, the two Linum species have different growth strategies. The strong differences in population dynamics between the two species suggest that similarity in population sizes and frequency of the species in the landscape may be more important when attempting to transfer knowledge between species than is taxonomic relatedness., (© 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.)