About Us | Help Videos | Contact Us | Subscriptions
 

Abstract

 

This article in SSSAJ

  1. Vol. 51 No. 3, p. 599-604
     
    Received: Dec 2, 1985
    Published: May, 1987


 View
 Download
 Alerts
 Permissions
 Share

doi:10.2136/sssaj1987.03615995005100030009x

A New Technique for Assessment of Reversibly Adsorbed Phosphate1

  1. S. E. A. T. M. van der Zee,
  2. L. G. J. Fokkink and
  3. W. H. van Riemsdijk2

Abstract

Abstract

A new desorption technique for soil phosphate is described, in which Fe oxide coated filter paper is used as an “infinite” sink for P. This technique is applied to study desorption kinetics for nine sandy soils. The desorption can be explained with a simple Lang-muir kinetics model. The mean value of the desorption rate constants found is kd = 0.2 ± 0.08 h−1. The estimated errors that are due to re-equilibration during the experiments are less than experimental error. The amounts of P desorbed with the new technique, Pi, are compared to the amounts that desorb if a conventional dilution technique, Pw, is used. The new technique desorbs more P than the conventional method (Pi > Pw). By comparing Pi with oxalate-extractable P (Pox) it is evident that reversibly adsorbed P rarely exceeds one-third of Pox. Differences between the soils can be explained in terms of the oxalate-extractable amounts of Fe and Al.

  Please view the pdf by using the Full Text (PDF) link under 'View' to the left.

Copyright © . Soil Science Society of America