The influence of Calamagrostis villosa on the species diversity of deforested sites in the Krušné hory Mts.

The effect of Calamagrostis villosa on the performance of the other species present in the community was studied in the Krušné hory Mts. Higher species richness was found in the moist meadow invaded by C. villosa than in the deforested site completely dominated by this species. Log-series distribution of species abundances was the best fit, especially in the deforested site. The diversity indices used (α, H') were able to discriminate significantly (P < 0.001) between sites. In the moist meadow, the relationships were studied on the within-community level. Number and total biomass of the other species decrease with the biomass of C. villosa, both being more closely related to its litter (P < 0.01) than to its living biomass (P < 0.05). Linear increase of evenness J' of the other species with C. villosa total biomass was recorded. The species diversity H' showed no significant relation to the C. villosa productivity. Performances of all but two species are significantly negatively correlated with C. villosa biomass. Differentiated relationships of the other species to C. villosa litter and live biomass may be interpreted with respect to their growth forms and life strategies.