In terms of 5-year pot experiment in acidic soddy-podzolic sandy soil the dissolution rate of the conversion of chalk (KM), introduced in evidence and deliberately exaggerated doses was studied. It was shown that the complete dissolution of the chalk depending on the dose of application was completed for 3-4 years after liming. Tracked changes in the content of humic acids related to calcium in the composition of humus during liming of the soil the increasing doses of ameliorant and in the process of its dissolution. It was established that the increased content of humic acids related to calcium, in the experiment with increasing doses of ameliorant continued until the variant with a dose of application of chalk corresponding to 1.6 Hg. The increase in HA-2 in the composition of humus in the process of dissolution of the ameliorant made in a deliberately exaggerated dose (2.5 Hg), observed up to 3-year aftereffect of ameliorant. On the basis of two experiments revealed that the maximum level of accumulation GK-2 in the composition of humus does not exceed 16% of the collective. Developed mathematical models describing the process of accumulation HA-2 in the composition of humus under the action of liming. It was revealed that depending on the experience in compounds with humic acids in limed soils were quite significant quantities of calcium from 570 to 1480 kg/ha in terms of CaCO3.