Changes in the Phosporus Status of Paddy Soils after the Addition of Phosphate and Lime

Abstract

Changes in the phosphorus status of five paddy soils were studied after the application of phosphate fertillizer and lime, and incubation under submerged conditions at room temperature for three weeks; the soil groups represented were Acid Sulphate, Fresh WaterAlluvial, Loamy Low Humic Gley, Grumusol and Sandy Low Humic Gley. Although lime application alone increased the level of available phosphorus, the increase was more marked in all soils when phosphate fertilizer was also applied. Inorganic phosphorus was the only form of phosphorus that together, thelevels of AI-P and Ca-P increased, while that for Fe-P decreased; extractable phosphorus also showed a marked increase.