Effects of pasture management and fertilizer regimes on botanical changes in species-rich mountain calcareous grassland in Central Europe

摘要

A 3-year experiment was conducted in Central Europe to examine the effects of three managements, viz. continuous cattle grazing from April to September, mowing once in July and abandonment of grazing, and two levels of fertilizer application, no fertilizer and 400 kg hap# of a NPK fertilizer, on changes in plant species composition and summer biomass of dry matter (DM) in a calcareous mountain grassland containing many plant functional types. Different managements led to changes in species composition due to species-specific responses. Low creeping and rosette species were associated with grazing, while grasses and tall forbs correlated with mowing and abandonment of grazing, probably because of their ability to outcompete rosette species. There was a negative relationship between the number of species and above-ground biomass and a positive relationship between number of species and below-ground biomass, suggesting that these species-rich communities allocate more to below-ground organs when not grazed. The application of fertilizer had no effect on species composition but it indirectly increased competitive asymmetry for light and increased the number of plant extinctions. It is concluded that continuation of cattle grazing is an acceptable form of grassland management at the study site and that species and functional group compositions can rapidly change with changing environmental conditions such as abandonment of grazing or application of fertilizer.