Effect of liming on the changes of different forms of potassium in an acid soil treated with N and K fertilizers

摘要

A laboratory experiment was conducted to study the effect of liming on the transformation of different forms of potassium in a strongly acidic silty loam soil (pH 4.56) treated with nitrogenous and potassic fertilizers: Irrespective of treatments, liming initially decreased the water soluble and exchangeable K but increased the non-exchangeahle K in soil. Water soluble K was significantly increased in limed soil throughout its incubation period, whereas it showed a decreasing trend in unlimed acid soil. Highest amount of exchangeable K was observed in acid soil after 90 days of incubation, whereas water soluble and non-exchangeable K were found to be highest in half and full limed soil respectively. Combined application of nitrogen and potassium fertilizer significantly increased the water soluble K. However exchangeable K was increased in sole potassium fertilizer treated system. Application of N along with K fertilizer influenced soil K fixation and release of K because of its antagonistic interaction between NH4~+ and K~+ for the same fixing sites.