Division of Soil Science and Microbiology, Central Rice Research Institute, Cuttack, Orissa, 753006
The transformation of added water soluble sulphate was studied in relation to the changes in Eh, pH, extractable iron and manganese in eight different rice growing soils under flooded condition. It was observed that the transformation was mainly governed by changes in Eh, and partly by pH, iron and manganese. The extractable sulphate decreased moderately up to 10 days and rapidly thereafter. The reduction of sulphate was hastened at a redox potential below −160 mV and/or in the pH range of 6.4 to 7.7.
Sulphate transformation, redox potential, extractable iron and manganese, rice soils
