DIFFERENTIAL RESPONSE OF SOIL TEXTURE FOR LEACHING OF SALTS RECEIVING DIFFERENT PORE VOLUMES OF WATER IN SALINE-SODIC SOIL COLUMN

This study examined the leaching requirement of three saline-sodic soils in polyvinyl chloride (pvc) columns of 50 cm long and 11 cm internal diameter. air-dried soils were packed in pvc lysimeters receiving different pore volume (pv) of water (ec 0.89 ds m^-1, sar 1.55, rsc 1.02 mmolc l^-1). leaching with 2.5 pv of water removed 94 % of soluble salts and decreased ece from 33.9 to 5.9 ds m^-1 in 0-25 cm layer of sandy clay loam soil. for lowering ece to < 4 ds m^-1 in loamy sand up to 0-25 cm soil layer, 2.0 pv water removed 67 % soluble salts. in silty clay loam soil, 2.5 pv water lowered ece to < 4 ds m^-1 only up to 0-10 cm depth with 83 % removal of salts. relationships between ec/ec0 and dw/ds established were for the soils as ec/ec0 = 0.329 (dw/ds)^-2.12 with r= 0.87 for loamy sand; ec/ec0 = 0.167 (dw/ds)-0.60 with r=0.89 for silty clay loam and ec/ec0 = 0.06 (dw/ds)0.78 with r=0.98 for sandy clay loam soil. these relationships leads to conclude that reduction in salinity of loamy sand, silty clay loam and sandy clay loam soil was 67, 83 and 94 % when leached with 1.88, 2.72 and 2.67 cm of water, respectively.