Lichens and bryophytes of the alpine and subalpine zones onKatandin, Maine, II: Lichens

摘要

A total of 293 different lichens (and lichenicolous fungi) were found above anelevation of 884 m on Katandin during fieldwork from 2000 to 2004 and from study ofpreviously collected herbarium specimens. Thirteen of these are new to North America, 39additional lichens are new to northeastern United States and 26 additional ones are new toMaine; three additional taxa are almost certainly new to science but are not formally described in this study. We identified eight distinct lichen habitats on Katandin: (1) Al,exposed alpine tundra and fellfields; (2) A2, high elevation alpine sites protected fromnorthwest winds; (3) A3, east-facing alpine late-snow areas; (4) A4, alpine krummholz; (5)A5, cirque headwalls facing east and north; (6) A6, cirque headwall facing southeast; (7)B 1 , exposed low-altitude tundra, talus and krummholz; and (8) B2, subalpine forests. Eachhabitat except A4 had numerous lichens (10-56 taxa) found in none of the others, andeach differed statistically from two to six other habitats by a quantitative measure of theArctic-boreal-temperate (ABT) distribution of its lichens. Habitat A3 had, on average, themost Arctic lichens, followed by Al, A2, A5, B1, A6 and A4, with B2 having the fewestArctic lichens and the most with a temperate distribution. Lichen ABT values for the eighthabitats are well predicted (R2 = 96.9%) by a multiple regression equation incorporatingthree independent variables: average elevation above sea level of the lichens collected in ahabitat class; an estimate of solar gain for each of the eight habitats; and the presence orabsence of trees (including krummholz). We compared our results with those for Mt.Albert, Gaspe, Quebec, the only other comprehensive study of alpine lichens innortheastern North America, for such parameters as species presence/absence, substrataand ABT value. We suggest that future studies looking into effects of global warming orincreases or decreases in air pollution will be facilitated by the study of certain habitatsrather than the entire alpine and subalpine Katandin region.