The recent history of treeline at the northwest limit of white spruce in Alaska
Rowland EL. 1997. The recent history of treeline at the northwest limit of white spruce in Alaska. University of Alaska Fairbanks
(Author's abstract) 'To understand how the northwestern-most treeline in Alaska has responded to chages in climate since the 19th century, I investigated the history and autecology of white spruce in two tributaries valleys of the Noatak River. A pollen record from Loon Lake extends back to ca. 6,000 years B. P. and indicates that spruce was growing around the mouth of the Kelly River (the middle Noatak Valley) by at least 1,900 years ago. Data collected from white spruce stands in the Kelly and Kugururok River valleys suggest that treeline in these areas became established within the last 600 years. Although the rate of recruitment in the spruce stands has been fairly steady throughout the last three centuries, recruitment did increase between A. D. 1920 and 1950 in response to the Northern Hemisphere temperature maximum. This response is evidence by increased density in white spruce stands in valley bottoms and by the upslope movement of the altitudinal limit of spruce. The data from the study areas in the Kelly and Kugururok River valleys indicate that white spruce treeline has not extended beyond its current limit during the last 300 years.'
- Type
- Academic
- Authors
- Rowland, E
- Date of Issue
- 1997
- Publisher
- University of Alaska Fairbanks
- Units
- CAKN , DENA , NOAT , YUCH , WRST
- Keywords
- Boreal Forest, Botany, Ecotones, Flora, Forests, Noatak National Preserve Alaska, Northwest Alaska, Plant Studies, Subarctic, Taiga, Thesis, Vascular Plants, Vegetation, White Spruce