Extração e determinação do íon amônio do solo

Abstract

This paper reports the ammonium determination in soils, by the colorimetric method of Nessler. Several aspects were studied, like the absorption spectra of the color compound and the Nessler's reactive, the action of the time of standing and the temperature on the development of the color and the interference of some ions which are normaly in the soils extracts. The ammonium determination wasmade in soil extracts obtained with KC1 1 N solution and distilled, in order to prevent the interference of manganous ion, which gives a precipitated with the Nessler's reactive. The results were compared with the those obtained by the tritrimetric method.