Abstract: The specific features in the formation of a system of biologically active surface horizons (organoprofile) in the Subantarctic lithozems (Leptosols) are analyzed using mathematical modeling. Simulation experiments involve the ROMUL mathematical model. The working scenarios are compiled taking into account the specific features of the effects of climate, fauna, and vegetation of the coasts of King George Island, archipelago of the South Shetland Islands, West Antarctica. The periodicity of temperature recording (using daily or monthly average values) has little effect on the simulation results. As is shown, different localizations of the litterfall under green mosses and Antarctic hair grass (Deschampsia antarctica) lead to development of the organoprofiles differing in their structure and quality. The enrichment with nitrogen due to the vital activity of penguins increases the litterfall transformation intensity and enhances humification. Note that the results of a medium-term (50-year-long) simulation of the dynamics of organic matter pools in the lithozems with different ornithogenic impacts significantly differ in the case of a change in vegetation type and an increase in the nitrogen concentration in litterfall. Long-term (at constant climate and litterfall) computational experiments have shown that the litter and humus pools under the Subantarctic conditions reach a stable state in 200 and 500 years, respectively. Soil CO₂ emission in the simulated ranges of soil forming factors can be regarded as consistent with the results of field measurements if a large part of the gross СО₂ flux results from the respiration of vegetation. The compilation of scenarios for simulation experiments has shown that the field information on the pools of surface organic horizon (litter) and their quality for drained Antarctic soils is insufficient. Litter is an important indicator of the actual response of Antarctic soils to the change in soil forming factors and must be taken into account. We invite the international community of the scientists studying the soils of Antarctic to agree on the unification of descriptions of the key sites and calculations of the results of field studies.