Colossal carbon! Disturbance and biomass dynamics in Alaska's national forests

Abstract

The Chugach and Tongass National Forests are changing, possibly in response to global warming. Forested areas within Alaska's temperate rain forests are creeping into areas that were previously too cold or too wet. These forests are also becoming denser. As biomass increases, the amount of carbon stored in the forest also increases. Tara Barrett, a research forester with the U.S. Forest Service, Pacific Northwest Research Station, recently measured these changes. She and her colleagues compared Forest Inventory and Analysis survey data collected from 1995 to 2003 with follow-up inventories taken from 2004 to 2010. The comparison showed that carbon mass increased 4.5 percent in live trees in the Chugach. Carbon storage remained about the same in the Tongass; however, tree species there changed slightly. These observed changes in the Chugach and Tongass National Forests may be related to warmer temperatures and higher levels of carbon dioxide in the atmosphere. This research is being used by the U.S. Forest Service and other government agencies to assess the vulnerability of Alaska's forests and to plan for their future. The Chugach National Forest, for example, used it to establish a baseline assessment of carbon stocks in accordance with 2012 forest planning rules.

Citation

Kirkland, John; Barrett, Tara. 2016. Colossal carbon! Disturbance and biomass dynamics in Alaska's national forests. Science Findings 182. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 5 p.