Calibration preliminary results of a portable kit for soil chemical analysis
A study to test and calibrate a portable kit for soil chemical analysis (La Motte). The methodology used was colorimetric comparison between values obtained in laboratory using an initial set of soils and their corresponding colors according to color Kit tables (color charts) which presented colors and were not established and without significant correlations. New comparisons were made with their replication and this meant that the original color charts were adjusted with a series of local soils (soil patterns) and their comparisons showed highly significant correlations. The parameters evaluated were: phosphorus (P), potassium (K), iron (Fe), magnesium (Mg), manganese (Mn) and pH. Evaluated soil samples were taken in different municipalities, The sites were selected according to the needs of the elements suggested by the calibration to be performed and the agricultural managements as coffee (Coffea arabica), corn (Zea mays), bean (Phaseolus vulgaris L.), sugarcane (Saccharum officinarum), potato (Solanum tuberosum), pea (Pisum sativum) among others and provided necessary patterns soils. Pearson correlation tests showed highly signiicant correlations for the parameters pH, P, K, Al, Fe, Mg, Mn, when used color charts adjusted to standard samples. The parameters Ca, Cu and M.O. showed no significant correlations because the adjusted pre-calibration requires a wider range of chemical analysis of the soil samples to adjust methodologies.