| Popis: |
The clonal sedge, Carex bigelowwi Torr. ex Schwein., is common in the subarctic range lands of the Icelandic Highlands, which are grazed during summer, mainly by sheep. The effects of grazing on tiller and the population dynamics were studied by comparing grazed and ungrazed sites at two altitudes. On a tiller basis, C. bigelowii responded to grazing by decreased tiller size and reduced probability of flowering while on a unit area basis, both density and biomass increased. The moss Racomitrium lanuginosum (Hedw.) Brid., also abundant at the study sites, is not grazed but sensitive to trampling. The moss dry weight was four times greater at an ungrazed site than at a comparable grazed site |
