Sanchez L. S. H., Horbe A. M. C., Moquet J. S., Sondag Francis, Guyot Jean-Loup. (2015). Variaçao espaço-temporal do material inorgânico dissolvido na bacia Amazônica. Acta Amazonica, 45 (2), p. 175-185. ISSN 0044-5967.
Titre du document
Variaçao espaço-temporal do material inorgânico dissolvido na bacia Amazônica
Sanchez L. S. H., Horbe A. M. C., Moquet J. S., Sondag Francis, Guyot Jean-Loup
Source
Acta Amazonica, 2015,
45 (2), p. 175-185 ISSN 0044-5967
The Amazon River basin is important in the contribution of dissolved material to oceans (4% worldwide). The aim of this work was to study the spatial and the temporal variability of dissolved inorganic materials in the main rivers of the Amazon basin. Data from 2003 to 2011 from six gauging stations of the ORE-HYBAM localized in Solimoes, Purus, Madeira and Amazon rivers were used for this study. The concentrations of Ca2+, Na+, K+, Mg2+, Cl-, SO4-2, HCO3- and SiO2 were analyzed. At the stations of Solimoes and Amazon rivers, the concentrations of Ca2+, Mg2+, HCO3- and SO4-2 had heterogeneous distribution over the years and did not show seasonality. At the stations of Madeira river, the concentration of these ions had seasonality inversely proportional to water discharge (dilution-concentration effect). Similar behavior was observed for the concentrations of and Na+ at the stations of the Solimoes, Amazon and Madeira rivers, indicating almost constant release of Cl- and Na+ fluxes during the hydrological cycle. K+ and SiO2 showed almost constant concentrations throughout the years and all the stations, indicating that their flows depend on the river discharge variation. Therefore, the temporal variability of the dissolved inorganic material fluxes in the Solimoes and Amazon rivers depends on the hydro-climatic factor and on the heterogeneity of the sources. In the Madeira and Purus rivers there is less influence of these factors, indicating that dissolved load fluxes are mainly associated to silicates weathering. As the Solimoes basin contributes approximately 84% of the total flux of dissolved materials in the basin and is mainly under the influence of a hydro-climatic factor, we conclude that the temporal variability of this factor controls the temporal variability of the dissolved material fluxes of the Amazon basin.
Plan de classement
Hydrologie [062]
;
Géologie et formations superficielles [064]
