ИСТИНА

This presentation summarizes the attempts of authors to find an appropriate place for most common variants of technogenic soils, by constructing a bridge between artificial and natural soils. Two assumptions were accepted: (i) humanly modified soils form a continuum from artificial, then – quasi-natural soils to non-soils (technogenic surface formations, technic materials); (ii) some approaches in diagnostics and terminology should be implemented from the new national soil classification system. The former assumption provides for intergrades that were rather neglected in the existing systems, while the advantages of latter one are: possibility to apply diagnostic horizons as main tools for identifying soils, transferring rules of nomenclature, and sustaining continuity in classification system, which essentially facilitates surveys. However, type of impact (soil-forming agent!) was preserved as criterion for the upper level; we believe that this is inevitable for humanly modified soils even in a substantive classification system. One more feature is specific: the hierarchical levels differ (in number and volume) from the traditional ones for natural soils. In this way, at least three high-level groups are proposed: urban, chemical and technical soils with two subgroups in each: strongly modified soils and intergrades. Strongly modified soils – Urbanozems, Chemozems and Technozems – have new horizons or new properties dictated by the type of impact (environment), namely urbic (UR), technogenic (TG), chemically transformed (CH), and parent material. The latter may be either natural or artificial (mine spoils, municipal wastes, filled substrates, etc.). In the intergrades, new horizons are associated with the remnants of the initial ones, mostly subsoils. Soil names combine the qualifier ‘techno-’, ‘urbo-‘, or ‘chemo’ with the name of original soil identified by the residual horizon, f.i., Urbo-podzol, Chemo-chernozem, Techno-cryozem. This approach was borrowed from the new Russian system, where various agro-soils are identified in accordance with their sets of diagnostic horizons (agro-chernozem, agro-grey soil), hence, at the type level. In terms of their taxonomic function, plow horizons are analogues of UR, TG, and CH horizons. Lower-level criteria are both ‘natural’ and ‘artificial’: gleyic, solonetzic and bituminous, ecranic, respectively. .