Evaluation of Soil Tests for Phosphorus in Lowland Ecosystem

Available P status as estimated by different extractants and its relationship with dif ferent inorganic P forms as influenced by various organic manures and P fertilizers under wetland ecosystem is reported. The P extracting power of different extractants was in the order: Mehlich I > Bray I > Truog > Olsen > Morgan. Olsen and B ray No.1 ext ractants were c onsistent in e xtracting P from specific P fractions than the other three extractants. Among the inorganic P f orms, Fe-P an d sal oid-P ar e the major contributors to available P as estimated by different extractants. The contribution of Fe-P fraction to available P was maximum.