Flooded rice soils of Northern Australia. II. Chemical profiles

Abstract

Changes in chemical and electrochemical properties of a flooded calcareous soil sown to rice were monitored during the season of flooding. Considerable variations in specific conductivity, individual cation concentrations, bicarbonate concentration, and carbon dioxide pressures were observed within the soil profile to depths of 30 cm. Redox potential and pH tended to be uniform within a profile except when CaSO4 or H2SO4 were added to the surface soil. Both field and pot experiments showed profile variations in soil properties and the significance of this is discussed in terms of the root distribution of rice.