This award is for a postdoctoral fellowship. The investigator will study the surface energy budget to improve our understanding of the controls on tree growth at the treeline in northern Alaska. Treeline positions have important implications for the surface ecology, the atmospheric circulation, and trace gas exchange in high-latitude landscapes. To test the hypothesis that soil water and nitrogen availability exert direct and indirect controls on tree growth along the hydrologic continuum in treeline environments, the soil moisture and nitrogen budgets will be manipulated to examine their interaction and their implications for growth at the treeline. The results that can be expected from this study would improve our ability to predict treeline shifts in a changing climate.
