Abstract

ARANGO PULGARIN, Gloria  and  PEREZ NARANJO, Juan Carlos. NITRATE AND AMMONIUM DETERMINATION IN SOILS USING ION SELECTIVE ELECTRODES. Rev. Fac. Nac. Agron. Medellín [online]. 2005, vol.58, n.1, pp.2733-2740. ISSN 0304-2847.

In order to evaluate an alternative method for quantifying different forms of nitrogen, the concentrations of nitrates (NO₃^-) and ammonium (NH₄) were determined by two methods: Colorimetry and Ion Selective Electrode (ISE), in soil samples from soils cultivated with flowers or banana in the department of Antioquia,Colombia. Regression and correlation analyses on the concentrations obtained from the two methods showed highly significant relationships among them. The determination of NO₃^- by means of colored complexes with brucine acid or by means of the use of an electrode selective for nitrates exhibited a highly significant coefficient of determination (R² = 99.2). In a similar way, determination of NH₄ based on the formation of blue colored complexes of indophenol or employing the electrode for ammoniac yielded a value of R² = 98.4. The use of electrodes has advantages over the colorimetric techniques, that require much more time and more costly equipment.

Keywords : Nitrogen; soil analyses; nitrates; ammonium.

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )