Profile Distribution of Various Chemical Fractions of Phosphorus in Soils of Varied Landscape of Western U.P.

摘要

Depth wise distribution of different chemical fractions of P in ten established soil series of the Western UP comprising three zones (Bhabar, Tarai and alluvial plain) was studied. The contents of total-P, saloid-P, Al-P, Fe-P, Ca-P occluded-P, reductant-P and available-P were found to vary from 140.63-867.19, 1.56-25.74, 3.52-62.93,1.56-85-86,28.13-510.50, 3.81-29.80, 12.30-164.26 and 0.70-35.31 mg/kgr1, respectively. The region wise profile mean contents of total-P, saloid-P, Al-P, Fe-P, occluded-P, reductant-P and available-P were found as: Tarai>Bhabar>alluvial zone, while that of Ca-P was arranged as :Bhabar>Tarai>alluvial zone. The contents of total, available and Al-P form were higher in surface horizons as compared to subsurface ones whereas, Ca-P and occluded-P followed a reverse trend. Saloid-P and Fe-P failed to follow any definite distribution pattern. A highly significant correlation existed between organic carbon and exchangeable. Ca~(2+) content and the different P fractions except that of Fe-P and occluded-P. The correlation among the various forms of P were also highly significant. Stepwise multiple regression showed that total and available P were highly dependent on the exchangeable Ca~(2+) and organic carbon content of the soil respectively. Among different P forms, available P was mainly dependent on the Al-P of soil.