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Submergence caused a small initial decline followed by a gradual increase in pH values of soil solution. At field capacity too, the pH showed similar trends but the changes were much less pronounced. The redox potential of soil solution decreased sharply and assumed negative value after five weeks of submergence. At field capacity, however, more or less similar values were maintained throughout the growing period of rice plants. Submergence caused an increase in concentration of both water-soluble iron and manganese. The concentration of water-soluble phosphorus increased upon submergence, reached maximum and then decreased. The changes in phosphorus concentration at field capacity were irregular. The concentration of nitrate decreased under submerged condition but the case was reverse at field capacity. Submergence resulted in an accumulation of ammoniacal nitrogen. At field …