Boron desorption in soils treated with organic and mineral fertilization

Boron (B) desorption in soils of the Latium Region (Italy) treated with a mineral fertilizer (ammonium nitrate), compost derived by wine-producing residues, integrated fertilization (resulting from addition of previously treatments), and organic mineral fertilizer, during the cropping session of lettuce (Lactuca sativa L. ev Bacio), were investigated. Boron desorption data could be expressed by the Freundlich isotherms for all the soils, that were able to continuously release boron. All fertilization treatments showed values of desorbed B higher than that of the unfertilized control, and therefore there was a positive effect of fertilizers regard to B release, particularly for organic mineral and integrated fertilizations. Correlations relating constants desorption and soil properties indicated that mostly the soil composition (clay, silt, and sand), and the iron and aluminum oxides would act on boron release.