Lime Requirement of Alluvial Acid Soils in Relation to Buffer pH Acidity Measured by Different Methods

Thirtyone alluvial acid soils from West Bengal were analysed for various forms of soil acidity and for exchangeable aluminium. The lime requirement was calculated from the buffer pH acidity determined by different methods. Simple regression analysis showed that lime requirement (LR) was significantly correlated with exchange, residual, and total acidity and exchangeable At, the highest correlation being with the LR values obtained by the method of Shoemaker, McLean and Pratt (SMP). Multiple regression analysis of LR with exchange acidity, residual acidity and exchangeable Al also showed the best relationship with the SMP method. The results indicated the importance of exchangeable Al besides exchange and residual acidity in determining the lime requirement of the alluvial acid soil of West Bengal and suggested the SMP buffer pH procedure to be relatively more suitable for these soils.