Submitted to: Soil Science Society of America Journal
Publication Type: Peer reviewed journal
Publication Acceptance Date: 11/13/2003
Publication Date: 5/20/2004
Citation: Goldberg, S.R., Suarez, D.L., Basta, N.T., Lesch, S.M. 2004. Predicting boron adsorption isotherms by midwestern soils using the constant capacitance model. Soil Science Society Of America Journal. v.68. p.795-801. Interpretive Summary: Boron is a specifically adsorbing anion that can be detrimental to plants at elevated levels. Detrimental levels can occur because of high levels of boron in the soil solution or from additions of boron via the irrigation water. Adsorption of boron by 22 soils was evaluated and predicted using a chemical model and easily measured soil chemical characteristics. Our results will benefit scientists who are developing models of boron movement in arid zone soils. The results can be used to improve predictions of boron behavior in soils and thus aid action and regulatory agencies in the management of soils and waters which contain elevated concentrations of boron.
Technical Abstract: Prediction of boron adsorption and transport has required detailed studies of B adsorption and subsequent determination of model parameters. In this study we tested a general regression model previously developed for predicting soil B surface complexation constants from easily measured soil chemical characteristics. The constant capacitance model, a chemical surface complexation model, was applied to B adsorption isotherms on 22 soils from the A and B horizons of 16 soil series from Oklahoma and Iowa. The measured chemical properties were surface area, organic carbon content, inorganic carbon content, and aluminum oxide content. The prediction equations were used to obtain values for B surface complexation constants thereby providing a completely independent evaluation of the ability of the constant capacitance model to describe B adsorption. The model was well able to predict B adsorption isotherms on the majority of the soils. The prediction equations developed from a set of soils primarily from California, were able to predict B adsorption on a set of soils from different parts of the country. This result suggests wide applicability of the previously developed model prediction equations for describing B adsorption both as a function of solution B concentration and solution pH.