Boron adsorption in lowland soils from southern of the state of Minas Gerais, Brazil

The objective of this study was to evaluate the B adsorption capacity in fo ur lowland soils from Lavras, MG, Brazil, through Langmuir and Freundlich i sotherm parameters. This study was conducted throughout October and Novembe r, 1998. Samples of Alluvial Soil, Low-Humic Gley Humic Gley and artificial ly drained Bog Soil were collected in 0-20 cm of profundity and sieved to 2 mm. Samples with or without liming application were incubated during 30 da ys. Duplicates of 4.0 g soil samples, conditioned in polyethylene tubes, re ceived eight doses of B (0, 2, 4, 8, 12, 16, 24 and 32 mug mL(-1)) prepared with 20 ml, CaCl2.2H(2)O 0.01 mot L-1 solution, using boric acid. The amou nt of B in the balance solution was measured through the Azomethine-H metho d. The high organic matter content in Humic Gley soil provided higher B ads orption capacity. The adsorption was highly correlated with organic matter, specific surface area, kaolinite, and exchangeable aluminum. Lime applicat ion provided decrease in B adsorption capacity for all soils.