Modern pollen rain and vegetation of the St. Elias Mountains, Yukon Territory

Abstract

The vegetation of the area east of the Klutlan Glacier in the St. Elias Mountains is described with the methods of European phytosociology. Four major vegetation types are recognized: Picea glauca forests, Populus balsamifera forests, Betula glandulosa shrub–tundra, and Dryas integrifolia tundra.The modern pollen assemblages deposited in these vegetation types are determined by pollen analysis of surface moss polsters, lake muds, and moss samples from sedge swamps. Numerical analyses of the surface spectra indicate that spectra from the Dryas tundra and from the Populus forests are distinctive in their pollen composition. The variation in the percentage pollen content of samples from the Picea forests and the shrub–tundra is so great, even when spectra from a single sample type are considered, that no reliable distinctions can be made in modern pollen spectra from these two community types.