Characteristics of Salt-affected Soils by Deep Tillage up to 600 mm: Disaggregation Experiments of Soil Clods

Abstract

A method is proposed for soil improvement of salt-affected soils. We envisaged that a layer of about 600 mm in depth could be tilled by a special plough, producing a coarse layer (soil clods) in the subsoil (B and C horizons) and cutting off the capillarity rise of groundwater. In this paper, indoor testing with soil bins was used to determine the proper size of the soil clods produced in the subsoil which will be used for design of a new plough configuration.The results showed that the porosity of the subsoil reached 0.49 where capillarity restarted, after 2000 mm of precipitation. The size of the soil clods of the B horizon should be about 10 cm to prevent collapse and loss of volume of the topsoil (A horizon). That of the C horizon should be about 14 cm to keep a longer capillarity interception.