Source: https://www.esoil.ru/publications/bulletin/862016ns/862016ns14.html
Timestamp: 2019-04-22 04:05:24+00:00

Document:
This paper discuss the changes in understanding of the central image of Vertisols and leading processes of their formation. The early concept described Vertisols as black or dark clayey soils with homogenous undifferentiated profile resulted basically of pedoturbation. The further studies discovered vertical differentiation of Vertisol attributes. The application of trench method discovered spatial heterogeneity of Vertisols with alternation of bowl and diapiric structures. Such spatial complex subsurface pattern seems to be rather common and can be found even in the absence of gilgai microrelief. A new central image of a mature Vertisol is a combination of two structural types, one being homogenous and monotonous, generally corresponding to the initial central image, and the other – heterogeneous profile with fragmented horizons. A leading process forming the new central image of Vertisols was defined as lateral shearing or plastic deformations, i.e., plastic movements and gradual upward pushing of moist material (analogy of defluction process). Pedoturbation or more exactly the vertical falling of surface material into the cracks results in the vertical mixing rather than in deformations. Micromorphological features typical of Vertisols and associated with shrink-swell phenomena, cracking, mixing and lateral shearing that are reflected in the central image of Vertisols are summarized in the paper and illustrated by microphotographs.
Key words: Vertisols, vertic (compact) soils, central image, morphology, microstructure, age, evolution.
1. W. A. Blokhuis, L. P. Wilding and M. J. Kooistra, “Classification of vertic intergrades: macromorphological and micromorphological aspects”, In: J.M. Kimble (Ed.), Characterization, classification and utilization of cold Aridisols and Vertisols. Proc. Sixth Int. Soil Correlation Meeting (ISCOM), (USDA Soil Conservation Service, National Soil Survey Center, Lincoln, 1991), 1–7 (1990).
2. Classification and Diagnostic System of Russian Soils (Oikumena, Smolensk, 2004) [in Russian].
3. R. Dudal, “Dark clay soils of tropical and subtropical regions”, In: FAO Agricultural Development. Paper No. 83 (FAO, Rome, 1965).
4. R. Dudal and H. Eswaran, “Distribution, properties and classification of Vertisols”, In: Vertisols: Their Distribution, Properties, Classification and Management,L.P. Wilding and R. Puentes (Eds.), Thech. Mono. No 18 (Texas A&M Printing Center, College Station, TX, 1988), 1–22.
5. V. M. Fridland, Soil Cover Structures of the World (Mysl, Moscow, 1984) [in Russian].
7. I. V. Kovda, E. G. Morgun and T. V. Alekseeva, “Development of gilgai soil cover in Central Ciscaucasia”, Eurasian Soil Science, 24(6), 28–45 (1992).
8. I. V. Kovda, E.G. Morgun, D. Williams and W. Lynn, “Soil cover of gilgai complexes: peculiarities of the development in subtropical and temperate climates”,Eurasian Soil Science, 36(11), 1168–1182 (2003).
9. I. V. Kovda, E. G. Morgun and E. A. Yarilova, “Micromorphological evidence of the gilgai soils polygenesis”, In: Soil Genesis, Geography and Evolution(Dokuchaev Soil Institute, Moscow, 1992) [in Russian].
10. I. V. Kovda and L. P. Wilding, “Vertisols: problems of classification, evolution and spatial self-organization”, Eurasian Soil Science, 37(12), 1341–1351 (2004).
11. N. B. Khitrov, T. V. Korolyuk, T. V. Tursina, N. P. Chizhikova, G. A. Shershukova, I. A. Beleneva and D. R. Morozov, “Compact soils of territories with gilgai microtopography”, Eurasian Soil Science, 27 (5), 1–18 (1995).
12. W. Lynn and D. Williams, “The making of a Vertisol”, Soul Survey Horizons, 33(2), 45–52 (1992).
13. A. R. Mermut, G. S. Dasog and G. N. Dowuona, “Soil morphology”, In: Vertisols and Technologies for their Management. Developments in soil science 24, N. Ahmad and A. Mermut (Eds.) (Elsevier, Amsterdam, 1996), 89–114.
15. Soil Survey Staff, Keys to Soil Taxonomy (Cornell University, Ithaca, NY, 1985).
16. C. H. Thompson and G. G. Beckmann, “Gilgai in the Australian black earth and some of its effects on plants”, Trop. Agric. Trinidad, 59, 149–156 (1982).
17. L. P. Wilding and D. Tessier, “Genesis of Vertisols: shrink-swell phenomena”, In: Vertisols: Their Distribution, Properties, Classification and Management, L.P. Wilding and R. Puentes (Eds.) Thech. Mono. No 18 (Texas A&M Printing Center, College Station, TX, 1988), 55–81.
18. L. P. Wilding, D. Williams, W. Miller, T. Cook and H. Eswaran, “Close interval spatial variability of Vertisols: A case study in Texas”, In: Characterization, Classification, and Utilization of Cold Aridisols and Vertisols, J.M. Kimble (ed.), Proc. Sixth Int. Soil Correlation Meeting, (USDA-SCS, National Soil Survey Center, Lincoln, NE. 1990), 232–247.
19. D. Williams and B.A. Touchet, “Microstructure and the bowl concept in Vertisols”, In: Classification, Management and Use Potential of Shrink-Swell Soils (New Delhi, India. 1988), 41–44.

References: V. 
 V. 
 V. 
 V. 
 V. 
 V. 
 V. 
 V.