ИСТИНА

Fires are very common climatically driven or man-induced factor having a strong impact both on natural and anthropogenic landscapes and soils. Fire-affected soils are most widely spread in forested areas or areas neighbouring forests. Anthropogenically induced fire events within settling areas are recorded in soils and habitation deposits at any environmental background. Long-term effects of severe fires on soils are recorded in their morphology as: 1. In situ accumulation of macromorphologically visible charcoals followed by their redistribution within soil profiles due to turbations; 2. Accumulation on a soil surface laterally transferred products of after-fire erosion (charcoal-rich colluvium); 3. Colour changes caused by fire: the blackness due to the accumulation of dispersed char and the redness produced by the transformation of iron oxides into hematite and maghemite. All these pyrogenic (fire-related) features are very resistant in time and have to be reflected in soil classification as diagnostic ones for fire effects. A wide geographic diversity of fire-affected soils and soil-sedimentary sequences will be presented to discuss fire-related morphological features and opportunities to imprint them in soil classification: 1. soil-sedimentary pyrogenic archives comprised series of Podzols and Arenosols including those in burial state in Keiva ice-marginal landforms of the Kola Peninsula, and in the karst landscapes of the Arkhangelsk Region (taiga landscapes of the Russian European North); 2. Cryosols under alpine meadows neighbouring mountain taiga developed on Holocene moraine in Aktru Valley, S-E Altai; soil-sedimentary series with surface and buried Chernozems under steppephytocenoses at a footslope neighbouring taiga slopes, Tyva mountains; soil-sedimentary series with surface and buried of Phaeozems in mountain taiga of Forth-Baikalia (South Siberia, Russia); 3. Urbic Technosols of an early medieval archaeological site in a desert of the Aral region, ancient delta-alluvial plain of the Syrdar'ya River (Kazakstan).