THE EDAPHIC CRITERIES OF SOIL-GEOGRAPHIC ZONATION OF FOREST-STEPPE LANDSCAPES OF VOLYNO-PODILLIA REGION

Abstract

Problem Statement and Purpose The existing scheme of soil-geographic zonation of Ukraine does not reflect the natural-historical structure of the landscapes of the Western Ukraine. The main criterias of soil-geographical zonation of forest-steppe landscapes of Volyno-Podillia are edaphic conditions, the role of chernozems in the zonal-provincial structure of soil cover, the peculiarities of adjacencies in soil combinations. The main taxonomic units of zonation are soil-geographical zone, kray (region), soil okrug (province) and rayon (district). The aim of the study was to create a scheme of soil-geographical zoning of forest-steppe landscapes of Volyno-Podilliaregion, which is based on the principles of structural approach to the spatial organization of soil cover. Data & Methods The literary sources, medium- and large-scale  soil maps, maps of relief plastics, Quaternary sediments were analysed. The main research methods were soilgeographical and qualitative-genetic. Also, the GIS‑technologies based on the software product ArcGIS10.3 were used, which allowed to draw the boundaries of taxonomic units of soil-geographical zoning and to form an attributive database. Results The forest-steppe zone stretches east from Opillia to the Podilsky forest massif on the Dnister-Pivdennyi Bug interfluve. We distinguished two soil-geographical krai: West-Podilskyi and North-Podilskyi and 9 soil okrugs as part of the forest-steppe zone of Volyno-Podillia. In the western part of the zone there is a synchronous spatial alternation of height-ordered erosion simple soil variations (lessivation-gleying) of gray and dark-gray forest soils with clay-illuvial chernozems, meadow and meadow-swamp soils of undulating beam interfluves of the Dnister left tributaries and complex soils variations-spotting (leaching-gleiing) of clayey-illuvial chernozems with typical chernozems deep and medium-deep deeply gleyed, meadow-chernozem of wide flat interfluves and ancient Pliocene valleys. In the east of the Podilskyi Forest-Steppe, complex variations-spotting of leaching-humus of dark-gray forest soils with clay-illuvial chernozems, typical deep chernozems and meadow-chernozem soils are dominated.