Measurement of organic ions in the Amazonian precipitation
Luciene
Lorandi
Lara, CENA – Lab. de Ecologia Isotópia, CENA/USP, Av. Centenário, 303 13400-970, Piracicaba, SP, Brasil., luciene@cena.usp.br
(Presenting)
Teotônio
Pauliquevis, Instituto de Física, Universidade de São Paulo, Rua do Matão, Travessa R, 187, São Paulo, S.P., Brasil., theo@if.usp.br
Mariana
Lino
Gouveia, Instituto de Física, Universidade de São Paulo, Rua do Matão, Travessa R, 187, São Paulo, S.P., Brasil., mariana@if.usp.br
Paulo
Artaxo, Instituto de Física, Universidade de São Paulo, Rua do Matão, Travessa R, 187, São Paulo, S.P., Brasil., artaxo@if.usp.br
As part of the LBA Millennium Institute, rainwater chemistry was measured in 3 long term wet deposition monitoring stations located in Balbina, Amazonas, Santarem, Pará, and Ouro Preto do Oeste, Rondonia. Organic ions were measured using ion chromatography, and trace elements were determined with ICP-MS for 3 years of measurements in each site. Concentrations of formic and acetic acids, sulfate, nitrate, phosphate, chlorine, sodium, potassium, magnesium, calcium, DOC (dissolved organic carbon), DIC (dissolved inorganic carbon) and others were measured. Ionic balance was achieved for the 3 sites, with the organic components being responsible for most of the ionic strength. Formic and acetic acids dominate the pH variability for all the sites. For Balbina, the average pH was 5.0. Significant deposition was observed for potassium, nitrogen compounds and organic acids for all 3 sites.