Vegetation structure and invasibility of arctic tundra

Plant productivity and the cover of shrubs, grasses and dead plant material in arctic tundra are predicted to increase and the cover of bryophytes to decrease in response to higher air temperatures. Eckstein et al. examine effects of manipulation of bryophytes and the litter layer on seedling recruitment of Anthoxanthum alpinum and Betula nana in subarctic Sweden. Whilst bryophyte and litter removal increases seedling emeregence in both species, Betula shows higher subsequent mortality where bryophytes have been removed, thus indicating that strong species-specific responses are likely to affect vegetation structure.