Carbon and water fluxes from ponderosa pine forests disturbed by wildfire and thinning

Dore, S. and Kolb, T. E. and Montes-Helu, M. and Eckert, S. E. and Sullivan, B. W. and Hungate, B. A. and Kaye, J. P. and Hart, S. C. and Koch, G. W. and Finkral, A. (2010) Carbon and water fluxes from ponderosa pine forests disturbed by wildfire and thinning. Ecological Applications, 20 (3). pp. 663-683. ISSN 1051-0761

Preview

Text Dore_S_etal_2010_Carbon_and_Water_Fluxes_from_Ponderosa_Pine_Forests(1).pdf - Published Version Download (822kB) | Preview

Abstract

Disturbances alter ecosystem carbon dynamics, often by reducing carbon uptake and stocks. We compared the impact of two types of disturbances that represent the most likely future conditions of currently dense ponderosa pine forests of the southwestern United States: (1) high-intensity fire and (2) thinning, designed to reduce fire intensity. High- severity fire had a larger impact on ecosystem carbon uptake and storage than thinning. Total ecosystem carbon was 42% lower at the intensely burned site, 10 years after burning, than at the undisturbed site. Eddy covariance measurements over two years showed that the burned site was a net annual source of carbon to the atmosphere whereas the undisturbed site was a sink. Net primary production (NPP), evapotranspiration (ET), and water use efficiency were lower at the burned site than at the undisturbed site. In contrast, thinning decreased total ecosystem carbon by 18%, and changed the site from a carbon sink to a source in the first post- treatment year. Thinning also decreased ET, reduced the limitation of drought on carbon uptake during summer, and did not change water use efficiency. Both disturbances reduced ecosystem carbon uptake by decreasing gross primary production (55% by burning, 30% by thinning) more than total ecosystem respiration (TER; 33–47% by burning, 18% by thinning), and increased the contribution of soil carbon dioxide efflux to TER. The relationship between TER and temperature was not affected by either disturbance. Efforts to accurately estimate regional carbon budgets should consider impacts on carbon dynamics of both large disturbances, such as high-intensity fire, and the partial disturbance of thinning that is often used to prevent intense burning. Our results show that thinned forests of ponderosa pine in the southwestern United States are a desirable alternative to intensively burned forests to maintain carbon stocks and primary production.

Item Type:	Article
Additional Information:	Copyright by the Ecological Society of America
ID number or DOI:	10.1890/09-0934.1
Keywords:	carbon sequestration; disturbance; ecosystem respiration; evapotranspiration; fire; forest management; GPP; NEP; Pinus ponderosa; soil respiration; thinning
Subjects:	Q Science > QH Natural history > QH301 Biology
NAU Depositing Author Academic Status:	Faculty/Staff
Department/Unit:	College of Engineering, Forestry, and Natural Science > Biological Sciences Research Centers > Merriam-Powell Center for Environmental Research College of Engineering, Forestry, and Natural Science > School of Forestry
Date Deposited:	20 Apr 2017 16:52
URI:	http://openknowledge.nau.edu/id/eprint/2909

Actions (login required)

IR Staff Record View

Downloads