EFFECTS OF CALCIUM CARBONATE, MANGANESE DIOXIDE, FERRIC HYDROXIDE, AND PROLONGED FLOODING ON CHEMICAL AND ELECTROCHEMICAL CHANGES AND GROWTH OF RICE IN A FLOODED ACID SULFATE SOIL

Abstract

Proposed provisional reclamation measures are: leach the soil with fresh water to lower the concentration of salts, chiefly sulfates; lime to an aerobic soil pH of 4.7 to prevent Al toxicity and to decrease iron toxicity; apply MnO2 to counteract Fe toxicity; add Fe2O3 (red earth) to counteract H2S toxicity in soils low in active Fe; and maintain a continuous flood after these combined treatments.