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Updated: Aug 15, 2026
10:16
Design and Operation of a Continuous 13C and 15N Labeling Chamber for Uniform or Differential, Metabolic and Structural, Plant Isotope Labeling
Published on: January 16, 2014
Forest structure and carbon dynamics in Amazonian tropical rain forests
Simone Vieira1, Plinio Barbosa de Camargo, Diogo Selhorst
1Laboratório de Ecologia Isotópica, CENA/USP, Av. Centenário, 303, PO-Box 96, Piracicaba, CEP 13400-970, SP, Brazil. savieira@cena.usp.br
Oecologia
|June 29, 2004
Summary
Tropical forest carbon dynamics vary significantly across the Amazon. Forests with longer dry seasons store less carbon and have younger trees, while those with consistent rainfall show near steady-state carbon balance.
Area of Science:
- Ecology
- Forest Science
- Climate Science
Background:
- Living trees are significant carbon reservoirs in tropical forests.
- Understanding tropical forest dynamics is crucial for predicting carbon storage and recovery from disturbances.
- Amazonian forests exhibit regional variations in topography, climate, and geology.
Purpose of the Study:
- To investigate variations in forest structure, biomass, and tree growth rates across different Amazonian sites.
- To analyze the impact of dry season length on carbon stocks and tree demographics.
- To estimate carbon balance in living wood and predict forest age.
Main Methods:
- Established permanent plots in eastern, central, and southwestern Amazonia.
- Measured forest structure, aboveground carbon stocks, and tree growth rates using dendrometer bands.
- Analyzed data considering factors like dry season length, stem frequency, biodiversity, and tree diameter distribution.
Main Results:
- Sites with longer dry seasons (Rio Branco, Santarém) showed lower stem frequencies, less biodiversity, and smaller aboveground carbon stocks compared to Manaus.
- Longer dry season forests stored a greater proportion of biomass in larger trees (>50 cm diameter).
- Annual carbon addition to living trees varied, with highest growth proportion in the 10-30 cm diameter class at all sites. Manaus forest estimated mean age is ~240 years, while Rio Branco and Santarém are ~140 years.
Conclusions:
- Forests in the Amazon exhibit distinct structural and dynamic differences influenced by climate, particularly dry season length.
- Manaus forest, with less seasonal rainfall variation, appears to be in a near steady-state carbon balance.
- Santarém and Rio Branco sites show accumulating live wood biomass, potentially linked to past disturbances, and harbor younger forests.
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