The ecotone between trees and the tundra in northern latitudes and with altitude in all areas of the world is a place where average temperature increases have been detected already. This increase in temperature is said to be caused by increased CO..2 in the global atmosphere. Whatever its cause, the effect will be to alter plant growth and distribution at the tree line ecotone. This study will investigate possible causes for limited tree growth at the tree line and thus provide fundamental data against which we may assess shifts in vegetation and the tree line as global CO.2 increases. Climatic change may best be detected at this cold dominated sensitive ecotone. The investigator, Dr. B. Sveinbjornsson, is an expert in northern latitude ecology, and his institution, University of Alaska, Anchorage, is well situated and equipped to support the work.
