| Summary: | The objective was to determine the major photosynthetic pigments in dry specimens of extant lichens as well as in Late Holocene subfossils that had been buried beneath ice in North Greenland. Dry specimens collected live contained up to 15 pigments, while subfossils of Umbilicaria cylindrica, U. krascheninnikovii, and U. hyperborea subfossils contained fewer, including chlorophyll a, in some cases chlorophyll b, and up to seven carotenoids. Concentrations were lower in subfossils, but pigments were shown to survive glaciation for up to 1,350 yr plus dry storage under herbarium conditions for up to 4 yr. High performance liquid chromatography revealed a preponderance of rapidly-eluted peaks in subfossils that were relatively inconspicuous in extracts of extant material, and these may have represented degradation products. Specimens of U. hyperborea were older than those of other species and yielded the lowest chlorophyll a/b ratios as well as the lowest Fv/Fm's values, reflecting limited shelf life of pigments. In all species chlorophyll a/chlorophyll b ratios and Fv/Fm readings were lower in subfossils than in comparable extant lichens. There was no evidence of major changes in pigments during the last millenium.
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