Record Details

Carbon stocks and changes on Pacific Northwest national forests and the role of disturbance, management, and growth

ScholarsArchive at Oregon State University

Field Value
Title Carbon stocks and changes on Pacific Northwest national forests and the role of disturbance, management, and growth
Names Gray, Andrew N. (creator)
Whittier, Thomas R. (creator)
Date Issued 2014-09-15 (iso8601)
Note To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/forest-ecology-and-management.
Abstract The National Forest System (NFS) of the United States plays an important role in the carbon cycle because
these lands make up a large proportion of the forested land in the country and commonly store more wood
per unit area than other forest ownerships. In addition to sustaining natural resources, these lands are
managed for multiple objectives that do not always align with maximizing carbon (C) sequestration.
The objectives of this study were to determine C stocks and flux in measured pools on Pacific Northwest
Region NFS lands and the major ecological drivers of C flux. We compiled tree, dead wood, and understory
vegetation data from 11,435 systematically-placed inventory plots and estimated growth, mortality,
decay, removals, and disturbance events based on two full measurements spanning 1993–2007. The area
of NFS-administered lands increased by 0.3% during this period and the area in formally-designated protected
status increased by 0.7%. There was 1293 Tg C (±11.2 Tg standard error) in non-soil C stocks at the
first measurement, which increased by 45 ± 2.2 Tg (3.4%), with 59% of the increase in the live tree pool and
the remainder in the dead tree pools. C stocks followed broad regional patterns in productivity while C flux
varied at local scales. Fires affected <1% of the forested area per year and were most prevalent in Wilderness
areas. Fires reduced C stocks on burned plots by only 9%, and had a negligible effect on the region as a
whole. Most tree harvest on NFS lands in the region consisted of partial harvest and had comparable
impacts to fire during this period. C sequestration rates were higher (1.2 ± 0.09 Mg/ha/yr) on the west side
of the Cascade Mountains, and primarily stayed in the live tree pool, compared to lower rates
(0.5 ± 0.04 Mg/ha/yr) east of the Cascades where most of the increase was seen in the down wood pool.
We discuss challenges to estimating forest ecosystem carbon stocks, which requires the application of a
large number of equations and parameters for measured and unmeasured components, some with scant
empirical support. Improved measurements and biomass models applied to networks of permanent plots
would enable improved ground-based estimates of the drivers and components of regional changes in C.
Genre Article
Topic Carbon sequestration
Identifier Gray, A. N., & Whittier, T. R. (2014). Carbon stocks and changes on Pacific Northwest national forests and the role of disturbance, management, and growth. Forest Ecology and Management, 328, 167-178. doi:10.1016/j.foreco.2014.05.015

© Western Waters Digital Library - GWLA member projects - Designed by the J. Willard Marriott Library - Hosted by Oregon State University Libraries and Press