Dynamic behavior evaluation of the fluvial dissolved and particulate loads in a small catchment reforested with eucalyptus

  • Diego Vendramini Universidade de São Paulo (CENA/USP)
  • Helder de Oliveira Universidade de São Paulo (CENA/USP)
  • Jefferson Mortatti Universidade de São Paulo (CENA/USP)
Keywords: hydrogeochemistry, fluvial loads, small catchments

Abstract

The main aspects of dissolved and particulate loads dynamic behavior in a small catchment of reforested eucalyptus were evaluated for two rainfall events of 28 and 25 mm before and after clear cutting. For the dissolved load, cations and anions varied inversely with the discharge, showing mechanisms of dilution, but with significant inputs before high discharges. The comparison between distribution concentrations curves with their theoretical dilution models revealed predominance of diffuse inputs, but with significant contribution of fertilization treatments, cases of K+, Cl- and SO42-, mainly after clear cutting. The fluvial particulate load, represented by suspended particulate matter (SPM), showed a positive relationship with discharges, with greater concentrations in higher flow rates for both periods. The relationship between MPS concentrations and discharges showed differences in the dynamics of remobilization and sedimentation processes influenced by precipitation, saturated soils conditions and hydrological regimes. Specific flows of MPS were approximately 2330.1 and 2121.1 g km-2 h-1, before and after clear cutting, respectively, indicating a major effect of the eucalyptus planted area on mechanical erosion.

Author Biographies

Diego Vendramini, Universidade de São Paulo (CENA/USP)
Laboratório de Isótopos Estáveis (LIE) do Centro de Energia Nuclear na Agricultura (CENA), Universidade de São Paulo (USP). Avenida Centenário, 303. CEP 13416-000. Piracicaba, SP.
Helder de Oliveira, Universidade de São Paulo (CENA/USP)
Laboratório de Isótopos Estáveis (LIE) do Centro de Energia Nuclear na Agricultura (CENA), Universidade de São Paulo (USP). Avenida Centenário, 303. CEP 13416-000. Piracicaba, SP.
Jefferson Mortatti, Universidade de São Paulo (CENA/USP)
Laboratório de Isótopos Estáveis (LIE) do Centro de Energia Nuclear na Agricultura (CENA), Universidade de São Paulo (USP). Avenida Centenário, 303. CEP 13416-000. Piracicaba, SP.
Published
29/08/2014
Section
Papers