Rates of Energy Storage and Stem Heat Fluxes in a Terra Firme Forest in Central Amazonia
Alessandro
Augusto
Michiles, Instituto Nacional de Pesquisas Espaciais, alemichiles@bol.com.br
(Presenting)
Ralf
Gielow, Instituto Nacional de Pesquisas Espaciais, ralf@cptec.inpe.br
To obtain the rate of energy storage (RES) in a “Terra Firme” forest during the dry season, an experiment was effected in Central Amazonia. Thus, the temperatures in three heigths and several radial depths of 4 stems of dominant species among the 670 trees of an 1 hectare site selected at the Estação ZF-2 (02°36’45” S, 60°12’40” W), plus the air temperatures and moistures, were measured. To compute the RES, all components which store energy during the day were considered: litter, minor components (palm trees and lianas), stem, branches, twigs, leaves and air. To obtain the RES of the stems, three methods were used. The first one uses all stem temperature measurements. The other ones, which are based on an analytical solution of the heat conduction equation, depend only on the temperature measurements in one radial depth of a tree with the average characteristics of the complete set. The RES of the other components was determined with the air and the average tree stem surface temperature measurements, plus the air moisture. One third of the RES of the forest is due to the stems, while other third is due to the air; finally, the last one is divided among the other parts. During the night and the transition periods, the RES of the forest (S) may constitute a sizable fraction of the net radiation (Rn), or even exceed it. On a daily basis, the values of S were observed between 1 and 10% of Rn, depending on the weather conditions.
Submetido por Alessandro Augusto dos Santos Michiles em 18-MAR-2004
Tema Científico do LBA: CD (Armazenamento e Trocas de Carbono)