Nitrate fate in a Mexican Andosol: Is it affected by preferential flow?
Por:
Prado, B, Duwig, C, Etchevers, J, Gaudet, JP, Vauclin, M
Publicada:
1 jul 2011
Resumen:
Andosols are the dominant soils in the Valle de Bravo basin, the origin of a significant amount of Mexico City's drinking water. The main land use is agriculture and most of the existing surface water bodies are eutrophic. Nitrogen fertilizer is used extensively. There have been very few studies on nitrate (NO(3)(-)) fate in this type of soil and region. Comprehensive laboratory studies were conducted to determine the fate of NO(3)(-) in an Andosol profile from Valle de Bravo, in order to assess the risk of water resources contamination. Nitrate retention was analysed statically (using batch experiments) and dynamically (using intact and packed soil columns) at different soil depths and its competition with Cl(-) was evaluated. Complementary laboratory experiments were conducted to study water transport through the columns and nitrogen transformations in the soil. In batch and columns, NO(3)(-) adsorption was linear in the range of concentrations studied and higher in the deepest soil
Filiaciones:
Prado, B:
Univ Nacl Autonoma Mexico, Inst Geol, Mexico City 04510, DF, Mexico
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