Improved method of analysing difficult soil extracts by flame atomic absorption spectrometry - Applicable to measurement of copper in ammonium oxalate extracts

Abstract

The advantages of a simple procedure, using very small volumes of solution (200 µl), in overcoming the difficulties associated with the aspiration of soil extracts containing either high salt concentrations or salts of low solubility, is illustrated by its application to the measurement of copper in ammonium oxalate extracts. Details of the simple precautions necessary to obtain optimum performance with the method are given. Relative standard deviations ranging from 12 to 3 % were obtained for soils containing 0.31-1.94 µg copper/g. Good agreement with the results obtained by a more time-consuming method, as well as satisfactory recoveries and the absence of the effect of dilution of the extract on the result, indicate the good accuracy of the proposed procedure.