ARCTIC LTER Predicting the Future Ecological Characteristics of the Toolik Lake Region

• Main Authors: John Hobbie, Knute Nadelhoffer, Bruce Peterson, Linda Deegan, Gus Shaver, Anne Giblin, Joe Vallino, Marine Biological Laboratory
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Arctic; Northern Foothills; Arctic grayling; Brooks Range; caribou; Dwarf birch; Moose; Tundra; Alaska
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.202.6102; http://ecosystems.mbl.edu/ARC/posters/Arctic_lter_all_science_poster.pdf

The site lies at 68 o N in the northern foothills of the Brooks Range, Alaska, in tundra vegetation of sedges and grasses mixed with dwarf birch and low willows. The tundra, streams, and lakes at the site have been undisturbed and unchanged for more than 5,000 years; caribou and moose move freely over this region pursued by wolves and grizzly bears. Populations of lake trout, char, and arctic grayling are in a pristine state, often dominated by very large and very old individuals. This allows the analysis of relationships in plants and animal communities in an ecosystem unaffected by an ecological legacy of human use. The climate of northern Alaska has changed remarkably over the past 30 years; the 0.7 o C per decade increase in temperature could result in much more than the 3-5 o total change predicted by GCM models for a doubling of CO 2 Based on several types of observations, there appears to be a biotic response to this regional warming. For example, the NDVI (a satellite-based indicator of plant biomass) has increased in northern Alaska, and vegetation communities at Toolik Lake show a reduction in moss cover and an increase in shrubs. The goal of this LTER project is to predict the future ecological characteristics of the site based upon our knowledge of the controls of ecosystem structure and function as exerted by physical setting and geologic factors, climatic factors