DETERMINATION OF SOIL TROPHICITY WITH ELECTROPHYSICAL METHOD. MESSAGE 2. ELECTRODE DESIGN AND THE METHOD OF GEOMETRIC COEFFICIENT CALCULATION

The purpose of this work is to determine the influence of the electrodes surface isolation, as well as the method of geometric coefficient calculation, on the results of determining specific electrical resistance of soils (ER or SER). Metrological characteristics for SER measurement, as well as the influence of the electrodes immersion depth into the substrate studied on this indicator, were determined. Nonlinear nature of SER dependence on the electrodes immersion depth was established. For non-insulated electrodes the dependence was well approximated by the power function regardless of the method of calculating geometric coefficient of installation. In case of partially isolated (point) electrodes the use of geometric coefficient for calculating geometric coefficient with an adjustment to the electrodes immersion depth into the substrate studied makes it possible practically to get rid of SER dependence on the electrodes immersion depth. The technique can be used to assess the soils trophicity in places where medicinal plants grow.