Plant seedlings in a species-rich meadow: effect of management, vegetation type and functional traits
(1) How do various mowing regimes used for the preservation of diverse meadow biota affect the occurrence of plant seedlings? (2) Does the effect of mowing regime on seedlings differ among vegetation types? (3) Are the seedlings occurring under a particular management type characterized by distinct functional traits? (4) Do the traits of seedlings differ from those of resident adult plant species?
White Carpathians (Bílé Karpaty) Mountains, Czech Republic.
In a species-rich meadow, seedlings (non-graminoids only) were identified to species and counted in an experiment that included management cessation and five mowing regimes in three types of vegetation for 2 yr. The abundance-weighted averages of functional traits were compared between seedling and adult plant communities.
Seedling occurrence was suppressed by management cessation (abandonment) but differences among the five mowing treatments were small for all vegetation types. Seedling density and species richness were highest in vegetation dominated by Bromus erectus, intermediate in vegetation dominated by Molinia arundinacea, and lowest in vegetation dominated by Calamagrostis epigejos. Comparison of functional trait composition of seedlings with that of adult plants revealed that seedlings were largely produced by species with no or limited clonal growth and with low stature, and therefore with lower competitive ability.
The results indicate that short-term alteration of the mowing regime does not change conditions conducive to seedling occurrence, but even short-term abandonment hinders the establishment of small, non-clonal species. Rapid changes in species composition after abandonment in temperate meadows are therefore due not only to competitive exclusion of subordinate plant species, but also to their inability to establish from seeds.