Monitoring air quality in class I wilderness areas of the northeastern United States using lichens and bryophytes
Gen. Tech. Rep. NRS-165. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern Research Station. 44 p.
To address a need for air quality and lichen monitoring information for the Northeast, we compared bulk chemistry data from 2011-2013 to baseline surveys from 1988 and 1993 in three Class I Wilderness areas of New Hampshire and Vermont. Plots were within the White Mountain National Forest (Presidential Range—Dry River Wilderness and Great Gulf Wilderness, New Hampshire) and the Green Mountain National Forest (Lye Brook Wilderness, Vermont). We sampled epiphyte communities and found 58 macrolichen species and 55 bryophyte species. We also analyzed bulk samples for total N, total S, and 27 additional elements. We detected a decrease in Pb at the level of the National Forest and in a subset of plots. Low lichen richness and poor thallus condition at Lye Brook corresponded to higher N and S levels at these sites. Lichen thallus condition was best where lichen species richness was also high. Highest Hg content, from a limited subset, was on the east slope of Mt. Washington near the head of Great Gulf. Most dominant lichens in good condition were associated with conifer boles or acidic substrates. The status regarding N and S tolerance for many lichens in the northeastern United States is not clear, so the influence of N pollution on community data cannot be fully assessed. Continued monitoring of lichens and bryophytes, especially if integrated with IMPROVE aerosol data, may reveal changes in air quality, climatic conditions, and other potential stressors or stimuli. Lichen health was impacted by low air quality at some of our sites.
Keywordslichens bryophytes air quality monitoring lead mercury nitrogen thallus condition IMPROVE National Forest Wilderness Area
Dibble, Alison C.; Hinds, James W.; Perron, Ralph; Cleavitt, Natalie; Poirot, Richard L.; Pardo, Linda H. 2016. Monitoring air quality in class I wilderness areas of the northeastern United States using lichens and bryophytes. Gen. Tech. Rep. NRS-165. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern Research Station. 44 p. https://doi.org/10.2737/NRS-GTR-165.