Understanding Phosphorus Accumulation and Movement in Vertisol and Inceptisol of North India

Abstract

Globally, there has been a greater concern over the application of fertilizer phosphorus (P) in excess to crop requirement which results in greater accumulation and loss to the surface water bodies. In a soil column study, two soils (Vertisol and Inceptisol) saturated with varying levels of their P sorption capacity were leached to study redistribution of P and leaching losses. Result of the soil column study indicated that P appeared in the leachates at 50 % P smax treatment in the Inceptisol. In the Vertisol, however, P in the leachate appeared at 150 and 200 % P smax only indicating that P movement in the soils was related to the clay content in the soils beside other factors. The water soluble P in the leachate of Vertisol and Inceptisol ranged from 0 to 0.54 µg ml−1 and 0 to 2.69 µg ml−1, respectively. Thus it appears that enhanced P movement in Inceptisol poses a greater threat to ground water pollution than in Vertisol.