Biogeochemical cycling of carbon, water, energy, trace gases, and aerosols in Amazonia: The LBA-EUSTACH experiments
Andreae, MO; Artaxo, P; Brandao, C; Carswell, FE; Ciccioli, P; da Costa, AL; Culf, AD; Esteves, JL; Gash, JHC; Grace, J; Kabat, P; Lelieveld, J; Malhi, Y; Manzi, AO; Meixner, FX; Nobre, AD; Nobre, C; Ruivo, MDLP; Silva-Dias, MA; Stefani, P; Valentini, R; von Jouanne, J; Waterloo, MJ
The biogeochemical cycling of carbon, water, energy, aerosols, and trace gases in the Amazon Basin was investigated in the project European Studies on Trace Gases and Atmospheric Chemistry as a Contribution to the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA-EUSTACH). We present an overview of the design of the project, the measurement sites and methods, and the meteorological conditions during the experiment. The main results from LBA-EUSTACH are: Eddy correlation studies in three regions of the Amazon Basin consistently show a large net carbon sink in the undisturbed rain forest. Nitrogen emitted by forest soils is subject to chemical cycling within the canopy space, which results in re-uptake of a large fraction of soil-derived NOx by the vegetation. The forest vegetation is both a sink and a source of volatile organic compounds, with net deposition being particularly important for partially oxidized organics. Concentrations of aerosol and cloud condensation nuclei (CCN) are highly seasonal, with a pronounced maximum in the dry (burning) season. High CCN concentrations from biomass burning have a pronounced impact on cloud microphysics, rainfall production mechanisms, and probably on large-scale climate dynamics.