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The Spatial Distribution of Forest Biomass in the Brazilian Amazon: A Comparison of EstimatesThe amount of carbon released to the atmosphere as a result of deforestation is determined, in part, by the amount of carbon held in the biomass of the forests converted to other uses. Uncertainty in forest biomass is responsible for much of the uncertainty in current estimates of the flux of carbon from land-use change. We compared several estimates of forest biomass for the Brazilian Amazon, based on spatial interpolations of direct measurements, relationships to climatic variables, and remote sensing data. We asked three questions. First, do the methods yield similar estimates? Second, do they yield similar spatial patterns of distribution of biomass? And, third, what factors need most attention if we are to predict more accurately the distribution of forest biomass over large areas? Amazonian forests (including dead and below-ground biomass) vary by more than a factor of two, from a low of 39 PgC to a high of 93 PgC. Furthermore, the estimates disagree as to the regions of high and low biomass. The lack of agreement among estimates confirms the need for reliable determination of aboveground biomass over large areas. Potential methods include direct measurement of biomass through forest inventories with improved allometric regression equations, dynamic modeling of forest recovery following observed stand-replacing disturbances (the approach used in this research), and estimation of aboveground biomass from airborne or satellite-based instruments sensitive to the vertical structure plant canopies.
Document ID
20040161149
Document Type
Reprint (Version printed in journal)
Authors
Houghton, R. A. (Woods Hole Research Center MA, United States)
Lawrence, J. L.
Hackler, J. L.
Brown, S.
Date Acquired
August 22, 2013
Publication Date
January 1, 2001
Publication Information
Publication: Global Change Biology
Volume: 7
Subject Category
Environment Pollution
Funding Number(s)
CONTRACT_GRANT: NAG5-9880
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.