Variation in ages and growth rates of trees in Amazonian tropical forests: consequences for carbon and forest management
Simone
Aparecida
Vieira, CENA/USP, savieira@cena.usp.br
(Presenting)
Plínio
Barbosa de
Camargo, CENA/USP, pcamargo@cena.usp.br
Diogo
Selhorst, SETEM/UFAC, dselhorst@pop.com.br
Niro
Higuchi, INPA, niro@inpa.gov.br
Luiz
Antonio
Martinelli, CENA/USP, martinelli@cena.usp.br
Susan
E.
Trumbore, University of California - Irvine, setrumbo@uci.edu
Tropical forests are important global carbon stocks and clearing of these forests is a major contributor to the accumulation of CO2 in the atmosphere, while logging is a major source of wood for world markets. A basic understanding of the dynamics of tropical forests is required both for predicting their future role as carbon sources or sinks, and for local design of sustainable extractive management practices.
Key to understanding the dynamics of tropical forests is the determination of the ages and growth rates of trees. As many upland tropical forest trees do not have annual growth rings, the estimates of tree age largely come from extrapolation of growth rates derived from permanent plot surveys or from dendrometer data. Uncertainties associated with these estimates are large because of assumptions of how growth rates change with tree age.
Growth rates for tropical forest trees estimated from radiocarbon ages and dendrometer measurements are in good agreement but show differences in forest age structure among three sites located in the eastern, central and western Amazon basin. The slowest growing trees are found in the Central Amazon, though individuals with ages >400 years are common across all sites. Biomass recovery in tropical forests can be rapid after slow-growing individuals are replaced with fast-growing pioneer species. However, biodiversity will only recover in centuries or longer if logging removes long-lived, slow growing species.
Submetido por Simone Vieira em 11-MAR-2004
Tema Científico do LBA: CD (Armazenamento e Trocas de Carbono)