Comparison of Different Carbonate Methods for Determining Calcic Chernozems

The accuracy and comparability of the results obtained from various methods for soil carbonate content measuring were verified. Volumetric (using a Scheibler calcimeter) and complexometric (using a complexing agent EDTA) methods, as well as the method of catalytic combustion (using a TOC-analyzer), were used. The object of study was the Calcic Chernozem, functioning both under grassy and forest vegetation, which provided a wide range of calcium carbonate content (0.18–19.9%). The results of the comparison have showed a high degree of correlation, provided that the data was grouped based on soil horizons that differed in terms of the dominant soil forming processes. Weak and average correlations were observed for humus-accumulative horizons, while high correlations were found in carbonate–illuvial horizons. Noticeable correlations were noted for horizons transitional to the parent rock. Volumetric and high-temperature catalytic methods were not sufficiently sensitive at low concentrations of CaCO₃.