9. Dependency between content of active calcium and a number of basic soil characteristics

Examples from cardinal soil areas in Bulgaria have been examined. Contents of CaCO₃, active Ca, pH(H₂0), humus and clay content have been defined. It is concluded that the method of determination of active Ca, has week sensitivity in non-calcaric and unsaturated soils. Within surface horizons results are influenced by composition of soil sorbtion capacity.