Phosphorus Fractionations in Ganges Tidal Floodplain Soil of Bangladesh

Abstract

CORRECTION: Due to a number of formatting and layout issues, the PDF of this paper was replaced on 10th October 2016. The page numbers of this article have changed from 55-61 to 57-63.

The present investigation aimed to evaluate different fractions of P of Ganges tidal floodplain soils of Bangladesh in terms of plant availability in the selected soil. The samples were analyzed for solution P, labile pool, alkali-extracted inorganic pool, organic pool, acidic pool and residual P.The soil solution P in the tested soils ranged from 0.03 to 0.11 mg L¹. The concentration of 0.5M NaHCO₃ extracted P had a range of 8-34 mg kg¹. Dilute NaOH extracted inorganic P had a range of 25-59 mg kg¹. NaOH extracted organic P ranged from 334 to 542 mg kg¹ and acid extracted P represented from 140 to 443 mg kg¹, respectively. Residual P of the tested soils showed a concentration of 104-262 mg kg¹. On average of the 12 soils, the relative concentration of solution P was 0.01%, NaHCO₃ P was 3.2%, NaOH-Pi was 6.8%, NaOH-Po was 44.6%, acid pool was 27.3% and residual fraction was 18.1%. Different P pools showed strong correlation either with sand, silt, clay, electrical conductivity, pH(H₂O), pH (KCl), organic carbon or extractable Fe content. The tested Ganges tidal floodplain soils demonstrated wide variation in the relative proportion of different P pools.

Bangladesh Rice j. 2015, 19(2): 57-63