About Us | Help Videos | Contact Us | Subscriptions



This article in SSSAJ

  1. Vol. 44 No. 1, p. 173-175
    Received: May 21, 1979
    Accepted: Sept 18, 1979

Request Permissions


An Automated Method for the Determination of Orthophosphate in the Presence of Labile Polyphosphates1

  1. L. E. Asher2



An automated method for determining orthophosphate in the presence of labile polyphosphates is described for the range 0–10 ppm orthophosphate-P. Interference by pyrophosphate and tripolyphosphate at concentrations of 10 and 200 ppm is < 1% of their P content. The precision of the method was satisfactory (the calibration curve has a correlation coefficient > 0.999 and a standard deviation around the regression line of ± 0.06), baseline drift was small, and only small changes in absorbance for the same standards over the course of 6 hours were observed. Analytical results obtained via the automated method for soil extracts and prepared mixtures compare favorably with analyses performed via the original manual method. One of the adaptations described also improves the original manual method.

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

Copyright © . Soil Science Society of America