Influence of aluminum on pH and recovery of exchangeable aluminum from peat

Abstract

Incubation experiment was conducted to obtain infomiation on tlie extent of acidity developed due to added AlCI, (0, 25, 50 and 100 tig g ') at different pH levels and changes in exchangeable A1 in peat. Results showed that A1 at high pH is hydrolysed causing an increased acidity by releasing H* from hydroxy aluminium compounds. Concentration of exchangeable A! is tremendously reduced with increasing pH possibly due to formation of mono-aluminium compounds or polynuclcar complexes of hydroxy aluminium. Extractable Al in IM KCI was very low Ix-cause of the presence of organic binding sites in peat. Thus, the recovery of exchangeable Al from Fisoii peat (I) containing more humified material was extremely low (1.0-2.1%) in comparison to Re^i Mo,‘?s peat (47.6-52.8%).