Positive Feedbacks in the Fire Dynamic of Closed Canopy Tropical Forests
Abstract
The incidence and importance of fire in the Amazon have increased substantially during the past decade, but the effects of this disturbance force are still poorly understood. The forest fire dynamics in two regions of the eastern Amazon were studied. Accidental fires have affected nearly 50 percent of the remaining forests and have caused more deforestation than has intentional clearing in recent years. Forest fires create positive feedbacks in future fire susceptibility, fuel loading, and fire intensity. Unless current land use and fire use practices are changed, fire has the potential to transform large areas of tropical forest into scrub or savanna.
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We thank C. Uhl, A. Taylor, G. P. Patil, F. Williams, and four anonymous reviewers for comments on earlier versions of the manuscript. This research was funded by a grant from the PPG7 “Programa de Pesquisa Dirigida” (MMA/MCT/FINEP). Additional financial support was provided by NSF, NASA, and the U.S. Agency for International Development.
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Published In
Science
Volume 284 | Issue 5421
11 June 1999
11 June 1999
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Received: 16 February 1999
Accepted: 16 April 1999
Published in print: 11 June 1999
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- Mark A. Cochrane et al.
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