EDAFOLOGÍA

Publicada por la Sociedad Española de la Ciencia del Suelo

 

Volumen 6. Diciembre 1999. pág 1-16.

 

 

RETENCIÓN DE SULFATOS EN SUELOS DE GALICIA: I. AJUSTE DE LAS ISOTERMAS DE ADSORCIÓN DE SULFATOS A LAS ECUACIONES DE LANGMUIR Y FREUNDLICH

 

M. Camps Arbestain, M.E. Barreal y F. Macías

Departamento de Edafoloxía e Química Agrícola, Facultade de Bioloxía, Universidade de Santiago de Compostela, 15706 Santiago de Compostela.

 

Abstract: Sulfate sorption isotherms (0.0-1.6 mM SO42-, initial pH 3.0) were generated for 24 acid forest soils from the surroundings of two-lignite-fueled power-generating plants in NW Spain (As Pontes and Meirama, A Coruña). Soils derived from biotitic schist and amphibolite showed generally high SO42- sorption capacities in accordance with the high levels of extractable Fe and Al that they contain. Soils developed from granite and phyllite exhibited lower SO42- sorption potentials that can be related to the lower content of reactive surfaces, sorption being particularly low in surface horizons rich in organic acids. A good fit to both Langmuir and Freundlich equations was obtained for the data, by means of non linear regressions. Stepwise multiple regression analysis was used to identify which combination of soil properties produced the best prediction of the Langmuir and Freundlich parameters (b, K, a, b). The predictions obtained were generally adequate, although further studies using soils not included in the data base are required to fully validate the equations.

Key words: Sulfate sorption, isotherms, Langmuir, Freundlich, acid deposition.

 

 

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