Spectrophotometric determination of aluminium in soil extracts with xylenol orange

Abstract

A spectrophotometric method for determining aluminium in soil extracts with xylenol orange at pH 3·8 is described. Various extraction reagents can be used. Interference of iron(III) and iron(II) is eliminated with EDTA. Rectilinear calibration covers a range of 0 to 60 µg of aluminium. Typical results are shown for an iron-humus podzol. Recovery of added aluminium and levels of interference of anions and cations relevant to soil analysis are shown. The practicability of the method in contrast with “lake” methods is emphasised.