Click on “Download PDF” for the PDF version or on the title for the HTML version.

If you are not an ASABE member or if your employer has not arranged for access to the full-text, Click here for options.

Feasibility of On-the-go Mapping of Soil Nitrate and Potassium Using Ion-Selective Electrodes

Published by the American Society of Agricultural and Biological Engineers, St. Joseph, Michigan

Citation:  Paper number  021183,  2002 ASAE Annual Meeting . (doi: 10.13031/2013.9159) @2002
Authors:   Viacheslav I. Adamchuk, Achim Dobermann, Mark T. Morgan, Sylvie M. Brouder
Keywords:   Site-specific management, soil sampling, ion-selective electrode, nitrate, potassium

A prototype of an automated soil sampling system for on-the-go measurement of soil pH has been developed and evaluated (Papers No. 98-3094, 99-1100 & 01-1045). It was shown that automated mapping of soil pH using ion-selective electrodes (ISE) on naturally moist soil is an effective alternative to conventional manual grid mapping. In this work the feasibility of applying a similar technique to map potassium and nitrate-nitrogen content was tested. It was found that polymer membrane K+ and NO3 - ion-selective electrodes can be used to predict other analytical measurement methods (atomic absorption spectroscopy and cadmium reduction) commonly used in soil laboratories. Significant correlations (R2 = 0.56 - 0.94) were observed while using both direct and soil solution measurements. Obtained results represent snapshots of real-time availability of K+ and NO3 - ions in soil solution, which could be used as indirect indicators for adjusting variable application rates of potassium or nitrogen fertilizers in combination with other layers of spatial data.

(Download PDF)    (Export to EndNotes)