Improvement of Salt-affected Soils by Deep Ploughing

—Part 2: Plot Field Tests in a Sodic Soil (Solonetz) Region—

Abstract

A method was investigated for improvement of salt-affected soils in regions where a sufficient amount of rainfall to percolate into subsoil occurs in summer. A coarse layer is provided in the subsoil by deep tillage, making soil clods to cut off the capillary rise from groundwater. This paper deals with plot test fields constructed by hand in a local spot of a sodic soil (solonetz) region. The results showed that deep tillage up to the subsoil (C horizon) was beneficial for improvement of the solonetz soil. Application of the gypsum also reclaimed the solonetz soil, and should be mixed into the A horizon. The pH values decreased from about 10 to 9. The EC values decreased from about 8 dSm ⁻¹ to 2 dSm^-1.