Conclusions
We detected a humped-back relationship between green biomass and species
richness in the studied sand pastures, but the plots characterised by
different grazing intensities were not separated along the biomass
gradient from each other. This clearly indicated that i) grazing
intensity levels assessed by the stocking rate on the pasture level is
too robust to assess effects of grazing intensity on the vegetation, and
ii) even sheep grazing created a highly patchy vegetation at the scale
of the biomass sampling both for species richness and biomass. These
results also suggests that in case we would like to reveal the
intensity-dependent distribution of biomass samples we need to use
multiple scales for sampling, and a fine-scale assessment of grazing
intensity. With this paper, we might take a step in revealing that the
stocking rate and the grazing frequency can jointly drive the
vegetation. In terms of grazing frequency, we formulated assumptions
based on the impact of proximity but to find clearer effects, a broader
knowledge about each pasture is needed e.g., with studying rotational
grazing or elaborating other ideas.