Loss and Retention of Nitrogen in an Artic Landscape: Key Pathways and Process Regulation

Marine Biological Laboratory, Woods Hole MA

Investigators

Abstract

The broad aim of this research is to improve understanding of how nitrogen (N) loss and retention processes affect long-term N accumulation and "N limitation" in terrestrial ecosystems. The specific aim is to determine the major pathways of N loss from Alaskan tundra ecosystems, the controls over those losses, and the importance of the losses for N accumulation and for interactions with the carbon (C) cycle. The field research will be based at Toolik Field Station, Alaska, and the research design is built around three core questions: What are the major forms and rates of N loss from different tundra ecosystem types? What are the major environmental and biological controls over these N losses? What are the impacts of N loss on overall N and C budgets of tundra ecosystems? The research design includes both field and laboratory experiments, and also the monitoring of N movement through soils and surface waters of a small watershed, Imnavait Creek. Simulation models will be used to construct N budgets at various timescales and to predict changes in N and C cycling in response to climate change and other disturbances.