Grazing promotes bryophyte species richness in semi-natural grasslands

We studied the effects of cattle grazing on bryophyte species richness in Finnish semi-natural grasslands and examined if there are differences among bryophyte life-strategies in relation to grazing pressure. We recorded species richness and cover of bryophytes in 420 sample plots located in 21 grasslands. Percentage of bare ground, height of vascular plant vegetation and cover of vascular plant litter were used as proxies for grazing intensity. We also explored the microhabitat preferences of individual species. Species richness of all bryophytes, perennial residents and colonists increased with grazing pressure. As compared with perennials, many species among the colonists had strong affinity to sites with high proportion of bare ground. We conclude that both perennial and colonist bryophytes benefit from grazing in semi-natural grasslands, although the effects of grazing are differently realized in the different bryophyte groups.