Contemporary Pollen Deposition and the Distribution of Betula Glandulosa at the Limit of Low Arctic Tundra in Southern Baffin Island, N.W.T., Canada

Abstract

Present-day pollen deposition in the 5000-km² coastal lowlands surrounding Frobisher Bay, Baffin Island, has been assessed using 105 polster samples representing 41 sites. Pollen percentages are presented for 33 taxa, with the emphasis on indicators of low arctic tundra, which is mapped for this area. Significant differences in the percentages of Betula pollen were found between sites classified as low arctic tundra by the presence of Betula glandulosa shrubs and those without, which are considered transitional middle/high arctic tundra. This result supports the paleobotanical interpretation of the Holocene pollen stratigraphy from the region. A time-lag in postglacial recolonization is suggested by the fact that the present Betula limit at the head of Frobisher Bay coincides with the position of the innermost (ca. 7000 BP) late Foxe recessional moraine.