Effect of grazing on the vegetation of shore meadows along the Bothnian Sea, Finland

The objective of this study was to evaluate the effects of grazing on shoreline meadows. To accomplish this, five ungrazed and four grazed meadow transects (a total of 411 1 m2 plots) were studied on the west coast of Finland (61° 30′–61° 33′ N/21° 28′–21° 41′ E). The summed cover of all species was decreased by grazing. The abundances of annuals+biennials, perennials, dicots and pteridophytes were decreased while the cover of monocots was increased by grazing. This trend was similar in all elevation classes and mainly both in the seashore and the delta. In the seashore grazing decreased the cover of chamaephytes and therophytes and in delta it seemed to increase the cover of geophytes and hemicryptophytes, but these results were influenced by differences in elevation. The height of vegetation and the dry biomass were smaller in the grazed than in the ungrazed plots. Agrostis stolonifera, Carex nigra, Festuca rubra, Juncus gerardii, Leontodon autumnalis, Poa subcaerulea and Potentilla anserina were more abundant in grazed, while the abundances of Filipendula ulmaria, Galium palustre, Lathyrus palustris and Phragmites australis were greater in ungrazed plots. Shores are multi-stress environments in which the water level fluctuation narrows the species pool. Grazing cattle is a disturbance, which has varied effects on different vegetation zones and on different kinds of species. Overall, it appears that stress-tolerant perennial monocots and halophytes are favored by grazing in those shoreline communities.