P. E. Carrara
Jane L. Smith
V. Anne
J. Johnson
T. A. Ager
2010
<p><span>An AMS radiocarbon-dated pollen record from a peat deposit on Mitkof Island, southeastern Alaska provides a vegetation history spanning ∼12,900 cal yr BP to the present. Late Wisconsin glaciers covered the entire island; deglaciation occurred > 15,400 cal yr BP. The earliest known vegetation to develop on the island (∼12,900 cal yr BP) was pine woodland (</span><span class="italic">Pinus contorta</span><span>) with alder (</span><span class="italic">Alnus</span><span>), sedges (Cyperaceae) and ferns (Polypodiaceae type). By ∼12,240 cal yr BP, Sitka spruce (</span><span class="italic">Picea sitchensis</span><span>) began to colonize the island while pine woodland declined. By ∼11,200 cal yr BP, mountain hemlock (</span><span class="italic">Tsuga mertensiana</span><span>) began to spread across the island. Sitka spruce-mountain hemlock forests dominated the lowland landscapes of the island until ∼10,180 cal yr BP, when western hemlock (</span><span class="italic">Tsuga heterophylla</span><span>) began to colonize, and soon became the dominant tree species. Rising percentages of pine, sedge, and sphagnum after ∼7100 cal yr BP may reflect an expansion of peat bog habitats as regional climate began to shift to cooler, wetter conditions. A decline in alders at that time suggests that coastal forests had spread into the island's uplands, replacing large areas of alder thickets. Cedars (</span><span class="italic">Chamaecyparis nootkatensis</span><span>,<span> </span></span><span class="italic">Thuja plicata</span><span>) appeared on Mitkof Island during the late Holocene.</span></p>
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10.1016/j.yqres.2009.12.005
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Cambridge University Press
Postglacial vegetation history of Mitkof Island, Alexander Archipelago, southeastern Alaska
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