EVALUACION DE LA CALIDAD AGRICOLA DE CUATRO ENMIENDAS CALCAREAS EN UN SUELO ACIDO DERIVADO DE CENIZAS VOLCANICAS

Abstract

The study described here involved an analysis of the agricultural quality of four types of limes applied to an acidic volcanic ash-derived soil. Soil samples were incubated in triplicate with 0, 1, 2, 3 and 6 g per kg^-1 soil of each of the four limes. The soil samples corresponded to Valdivia soil series (Typic Hapludand). Following 20 days of incubation at 23 ºC, the effect of the type of lime on soil pH (0,1M CaCl₂), exchangeable Ca (exCa), exchangeable bases (ExB), exchangeable Al (exAl) and aluminum saturation percentage (AlS %) was determined. To examine the effect of the type of lime on soil pH, exCa and exB, linear regressions were fitted to the data, and exponential equations were fitted to the data for exAl and Al %S. The t Student test was applied to the determined values of the slope (b) and curvature coefficient (k) to compare the behavior of different limes. The most sensitive acidity variable to differentiate between types of lime was the k value from exAl followed by k values from AlS % and b values from exCa and ExB. The least sensitive variable was found to be the b value from soil pH. These results are in agreement with the ENV values of the lime and predict agricultural quality behavior of each level type. This is most likely because of the characteristics of the incubation method, in terms of low temperature, which would have only allowed the small particle size of the limematerials to react completely as opposed to all of the lime material. This incubation method is different to other methods using high temperatures where bigger and smaller particles completely react giving results close to ECC values.