Effect of Subsurface Drainage System on Some Physicochemical Properties and Wheat Yield in Waterlogged Saline Soil

In a waterlogged sandy loam saline field (Camborthid) subsurface drainage (1.75 m depth) after 8 years of operation has resulted in appreciable reduction in soluble salts due to monsoon leaching and continuous cropping. Leaching increased soil porosity, modulus of rupture, infiltration rate, organic carbon and available water and decreased the hydraulic conductivity and bulk density in three drain spacings (25, 50 and 75 m). In 75 m drain spacing, however, soii salinit) (EC_e) and water content remained higher than in 25 and 50 m drain spacings. Soil EC_e and water content were less near the drains but maximum in area midway between the drains due to uneven leaching and the effects were more pronounced in summer season. The grain and straw yields were higher near the drains and decreased as the distance from the drains increased.