DETERMINATION OF NITRATE IN SOILS BY DIGITAL COLORIMETRY

A method for determining nitrate in soil by digital colorimetry is proposed. The developed approach is based on appropriate photometric techniques of nitrate determination after potassium chloride extraction from soil samples. The original method of determining nitrate in the form of an azo dye formed by the azo coupling reaction between 1-naphtylamine and sulfanilamide has been modifi ed to achieve a higher sensitivity and accuracy of colorimetric determination. This approach ensures metrological characteristics of the digital colorimetric technique, close to spectrophotometric. The adequacy of the proposed method was confi rmed by analyzing standard samples and soil samples collected in districts of the Moscow region.