Host–parasite distributions under changing climate: Tsuga heterophylla and Arceuthobium tsugense in Alaska
Dwarf mistletoes (Arceuthobium species) influence many processes within forested ecosystems, but few studies have examined their distribution in relation to climate. An analysis of 1549 forested
plots within a 14.5 million ha region of southeast Alaska provided strong indications that climate currently limits hemlock dwarf mistletoe (Arceuthobium tsugense (Rosendahl) G.N. Jones) to a subset
of the range of its primary tree host, western hemlock (Tsuga heterophylla (Raf.) Sarg.), with infection varying from a high of 20% of trees at sea level to only 5% by 200 m elevation. Three types
of modeling approaches (logistic, most similar neighbors, and random forests) were tested for the ability to simultaneously predict abundance and distribution of host and pathogen as a function of climate variables. Current distribution was explained well by logistic models using growing degree-days,
indirect and direct solar radiation, rainfall, snowfall, slope, and minimum temperatures, although accuracy for predicting A. tsugense presence at a particular location was only 38%. For future climate scenarios (A1B, A2, and B1), projected increases for A. tsugense habitat over
a century ranged from a low of 374% to a high of 757%, with differences between modeling approaches contributing more to uncertainty than differences between climate scenarios.
Document Type: Research Article
USDA Forest Service, Pacific Northwest Research Station, 3301 C Street Suite 200, Anchorage, AK 99503, USA.
Department of Forest Engineering, Resources and Management, 280 Peavy Hall, Oregon State University, Corvallis, OR 97331, USA.
USDA Forest Service, Pacific Northwest Research Station, 11305 Glacier Highway, Juneau, AK, 99801, USA.
Publication date: April 14, 2012
More about this publication?
Published since 1971, this monthly journal features articles, reviews, notes and commentaries on all aspects of forest science, including biometrics and mensuration, conservation, disturbance, ecology, economics, entomology, fire, genetics, management, operations, pathology, physiology, policy, remote sensing, social science, soil, silviculture, wildlife and wood science, contributed by internationally respected scientists. It also publishes special issues dedicated to a topic of current interest.
- Information for Authors
- Submit a Paper
- Subscribe to this Title
- Terms & Conditions
- Sample Issue
- Reprints & Permissions
- ingentaconnect is not responsible for the content or availability of external websites