Department of Soil Science, G.B. Pant University of Agriculture and Technology, Pantnagar, Uttar Pradesh
Laboratory equilibration studies showed that transformation of rock phosphate in soil was mainly related to soil acidity and phosphate potential as these two soil-parameters accounted for 94 per cent of variation in the degree of transformation of rock phosphate in 10 different soils. Lime potential or exchange acidity proved as good as pH for expressing soil acidity. Organic matter did not appear as a significant factor in influencing the transformation of rock phosphate.
Rock phosphate samples from different geographical sources differed in their reactivity as evident from the degree of their transformation in an acid soil. The samples from Mussoorie, Jhabua and Kasipatnam were more reactive than those from Udaipur and Jordan. This difference among the deposits was related to the citrate solubility of phosphate.
Rock phosphate, transformation in soil, soil characters
