A BASELINE STUDY OF ALPINE SNOWBED AND RILL COMMUNITIES ON MOUNT WASHINGTON, NH

摘要

Quantitative data on the abundance and frequency of vascular plants, bryophytes and lichens are lacking for alpine snowbed and rill communities in northeastern North America. Such data are needed to establish whether the communities are changing in response to climate warming, nitrogen deposition or shifts in the timing of precipitation and snowmelt. We surveyed nine sites (five snowbeds and four rills) on Mount Washington (White Mountain National Forest, New Hampshire), recording 54 vascular plant species, 42 bryophytes and 13 lichens. Although vascular plants were most abundant, bryophytes and lichens, which had not been completely surveyed in these communities previously, were important in terms of species richness (as many as eight bryophytes and four lichens in 1 m(2) quadrats) and were occasionally abundant, particularly bryophytes in rills. We found that snowbeds and rills are separate communities. Some species are shared, but far higher numbers of vascular plants, bryophytes and lichens were found in one community but not the other. The most frequent vascular plants had been reported as common in snowbeds and rills previously. However, several species that are common in these communities elsewhere occurred less often in our sites because of variation occurring both across the region and within the White Mountains. Our research provides baseline information on snowbeds and rill plant communities so that future studies can determine how they respond to changes in environmental conditions.