The development of approaches to assess the soil organic carbon pools in megapolises and small settlements

An approach to assess the soil organic carbon (SOC) pools in megapolises and in small settlements with due account for the natural, economic, and historical heterogeneity of urban territories; the degree of the soil sealing; and the specific features of their functional use is discussed. Cartographic information, satellite imagery, geoinformation systems, and field and literature data have been applied to adapt this approach for Moscow and for the town of Serebryanye Prudy in Moscow oblast. The pool of SOC has been calculated for the topsoil horizons (0-10 cm) and for the total thickness of the cultural layer (habitation deposits) in these urban areas. The total SOC pool comprises 13 833.0 × 10³ t (with an error of 30-40%) for Moscow and 2 996.6 × 10³ t (with an error of 50-70%) for Serebryanye Prudy. The specific carbon pools for these territories reach 128 and 810 t/ha, respectively. The cultural layer of Moscow concentrates about 75% of the total SOC pool; in Serebryanye Prudy, it contains about 95% of the total SOC pool. The SOC pools in the urban soils are comparable with or exceed the SOC pools in the corresponding natural zonal soils.