ИСТИНА

Paleosols of Trubchevsk district of the Bryansk region (Russia) lie in landscape with its own characteristic microrelief, called Trubchevsk Opole are well studied by paleopedologiests and paleogeographers. However, studies of the isotopic composition of the carbon is not carried out earlier for this territory. The radiocarbon data was obtained for two interstadial soils: 16,500 ± 230 Ki-17 414, 12 930 ± 170 Ki-17 413 years BP. According to the isotope ratios for organic carbon, vegetation growing on these soils refers to the C-3 type photosynthesis. The studied soils differ in chemical composition, magnetic susceptibility, and show two different stages in the development of soil cover. The ratio δ13Corg for underlying sandy pedosediments varies in range -26,5-27,2 ‰ characterizes relatively humid climate. The most lightweight carbon isotope composition (δ13C = -28,4-29,5 ‰) measured for the Holocene second humus horizon, opened in microdepressions of Trubchevsk opolye and dated 2180 ± 60 Ki-17 415 years BP. It is characterized by a high content of phosphorus, including its strong accumulation of organic compounds (635,8 mg/kg P2O5)