Chernozem

Chernozem
Chernozemic soil
Mollisol (USDA-NRCS)
Used inWRB, other
WRB codeCH
ProfileAhBC
Parent materialLoess
ClimateHumid continental

Chernozem (/ˈtʃɜːrnəzɛm/ CHUR-nə-zem), also called black soil, black earth, dark earth, regur soil or black cotton soil, is a black-colored soil containing a high percentage of humus (4% to 16%) and high percentages of phosphorus and ammonia compounds. Chernozem is very fertile and can produce high agricultural yields with its high moisture-storage capacity. However, prolonged agricultural use of chernozems still require replenishment with fertilizers because they easily can get depleted of nutrients through continuous decrease in humus content. Chernozems are a Reference Soil Group of the World Reference Base for Soil Resources (WRB). Chernozem is commonly found throughout the steppes of Russia and Ukraine, the American and Canadian Great Plains, and the South American Pampas according to most recent studies.

Etymology

The name comes from the Russian terms for black (чёрный čjornyj) and soil, earth or land (земля zemlja).

Distribution

Distribution of chernozem soils according to the World Reference Base for Soil Resources classification:
  Dominant (more than 50% of soil cover)
  Codominant (25–50%)
  Associated (5–25%)

Studies of the steppe soils of the Poltava region in the Russian Empire in 1883, conducted by geologist Vasily Dokuchaev, showed that the peasants called all soils by color, so the scientist began to use such names. Chernozem was black in color due to its large amount of soil organic matter. Dokuchaev was the first to describe the chernozem of the European part of the Russian Empire, and discovered its fertility. Although distinctly classified due to its high content of iron and aluminium oxides chernozem shares many chemical and physical properties with the terra preta of the Amazon rainforest, also called Amazonian dark earths.

Chernozem covers about 230 million hectares of land. There are two "chernozem belts" in the world. One is the Eurasian Steppe that includes the Peri-Carpathian Steppe, East European Forest Steppe, Pontic-Caspian Steppe, Kazakh Steppe and Mongolian-Manchurian Steppe. The other stretches from the Canadian Prairies in Manitoba through the Great Plains of the United States as far south as Kansas.

Chernozem layer thickness may vary widely, from several centimetres up to 1.5 metres (60 inches) in Ukraine, as well as the Red River Valley region in the northern United States and Canada (location of the prehistoric Lake Agassiz).

The terrain can also be found in small quantities elsewhere (for example, in 1% of Poland and Texas). It also exists in Northeast China, near Harbin. The only true chernozem in Australia is located around Nimmitabel, some of the richest soils on the continent.

Previously, there was a black market for the soil in Ukraine. The sale of agricultural land was illegal in Ukraine from 1992 to 2020, but the soil, transported by truck, could be traded legally. According to the Kharkiv-based Green Front NGO, the black market for illegally acquired chernozem in Ukraine was projected to reach approximately US$900 million per year in 2011.

Canadian and United States soil classification

Chernozemic soils are a soil type in the Canadian system of soil classification and the World Reference Base for Soil Resources (WRB).

Chernozemic soil type "equivalents", in the Canadian system, WRB, and U.S. Department of Agriculture soil taxonomy:

Canadian WRB United States
Chernozemic Kastanozem, Chernozem, Phaeozem Mollisol
Brown Chernozem Kastanozem (Aridic) Aridic Mollisol subgroups (Xerolls and Ustolls)
Dark Brown Chernozem Haplic Kastanozem Typic Mollisol subgroups
Black Chernozem Chernozem Udic Mollisol subgroups
Dark Grey Chernozem Greyzemic Phaeozem Boralfic Mollisol subgroups, Albolls
Source: Canadian system of soil classification (third edition)

Theories of chernozem origin

As seen in the list above, the 19th and 20th-century discussions on the pedogenesis of chernozem originally stemmed from climatic conditions from the early Holocene to roughly 5500 BC. However, no single paleoclimate reconstruction could accurately explain geochemical variations found in chernozems throughout central Europe. Evidence of anthropic origins of stable pyrogenic carbon in chernozem led to improved formation theories. Vegetation burning could explain chernozem's high magnetic susceptibility, the highest of the major soil types. Soil magnetism increases when soil minerals goethite and ferrihydrite convert to maghemite on exposure to heat. Temperatures sufficient to elevate maghemite on a landscape scale indicate the influence of fire. Given the rarity of such natural phenomena in the modern day, magnetic susceptibility in chernozem likely relates to control of fire by early humans.

Humification can darken soils (melanization) even in the absence of a pyrogenic carbon component. However, charcoal, also called black carbon when in the form of fine carbon particles, has been shown to be a prominent component of grassland soils in the Russian Steppe, the U.S. Great Plains, the Argentinian Pampa, the Manchurian Plains in China, and the Chernozem region in central Germany. Given the symphony of pedogenic processes that contribute to the formation of dark earths, chernozem summarizes different types of black soils with the same appearance but different formation histories.

See also

Notes

  1. ↑ Russian: Чернозём, romanized: Chernozyom, IPA: [tɕɪrnɐˈzʲɵm]; Ukrainian: Чорнозем, romanized: Chornozem; lit. 'black ground'.

References

  1. 1 2 "Origin and history of chernozem". www.etymonline.com. Retrieved 28 November 2025.
  2. 1 2 "Chernozem". Merriam-Webster online dictionary. 2008. Retrieved 28 November 2025.
  3. ↑ McAleese, John (28 July 2021). "How chemical pre-treatments in particle size analysis impact wind erosion modeling". AZoM.com. Retrieved 28 November 2025.
  4. ↑ Dzanagov, Sozyrko Khasanbekovich; Lazarov, Taimuraz Konstantinovich; Basiev, Aslan Eseevich; Kanukov, Zaurbek Tamerlanovich; Khadikov, Arthur Yurievich (June 2014). "Influence of sustained fertilization on the amount of humus and effective fertility of leached chernozem" (PDF). American-Eurasian Journal of Sustainable Agriculture. 8 (9): 35–40. Retrieved 28 November 2025.
  5. ↑ Lal, Rattan (21 June 2021). "Managing chernozem for reducing global warming". In Dent, David; Boincean, Boris (eds.). Regenerative agriculture. What’s missing? What do we still need to know?. Cham, Switzerland: Springer Nature. pp. 81–93. doi:10.1007/978-3-030-72224-1_7. ISBN 978-3-030-72224-1. Retrieved 3 March 2026.
  6. ↑ Deckers, Jozef; Gerasimova, Maria; Kabala, Cezary; Kravchenko, Yuriy; Nachtergaele, Freddy (2024). "Chernozem lecture notes" (PDF). WRB Documentation Centre, KU Leuven. Leuven, Belgium. Retrieved 4 March 2026.
  7. ↑ Allaby, Michael (21 March 2019). "chernozem (black earth)". A dictionary of plant sciences. Oxford, United Kingdom: Oxford University Press. ISBN 978-0-19-883333-8. Retrieved 1 December 2025. A freely draining soil profile whose name is the Russian word for 'black earth'
  8. ↑ Speake, Jennifer; LaFlaur, Mark (1999). "chernozem (also chernosem)". The Oxford essential dictionary of foreign terms in English. Oxford, United Kingdom: Oxford University Press. Retrieved 1 December 2025.
  9. ↑ Бережняк М.Ф. Ґрунтознавство: Навч. посіб. /М.Ф. Бережняк, Б.Є. Якубенко, А.М. Чурілов, Р.В. Сендзюк. // За заг. ред. Якубенка Б.Є. – К.: Видавництво Ліра-К, 2017. – 612 с. ISBN 978-617-7507-96-2
  10. 1 2 Dokuchaev, Vasily Vasilyevich (1967). Russian chernozem (1883). Selected works of V.V. Dokuchaev, translated in English by the Israel Program for Scientific Translations. Jerusalem, Israel: Israel Program for Scientific Translations. Retrieved 28 November 2025.
  11. ↑ Asare, Michael O. (September–October 2022). "Anthropogenic dark earth: evolution, distribution, physical, and chemical properties". European Journal of Soil Science. 73 (5) e13308. Bibcode:2022EuJSS..73E3308A. doi:10.1111/ejss.13308. Retrieved 28 November 2025.
  12. ↑ Hartemink, Alfred E. (2025). "Chernozems, carbon, climate". In Hartemink, Alfred E. (ed.). Pedology in the USA: life and Works of C. C. Nikiforoff (1886–1979) (1st ed.). Cham, Switzerland: Springer Nature. pp. 185–208. doi:10.1017/9781108937795. ISBN 978-3-032-00332-4. Retrieved 8 November 2025.
  13. ↑ Khitrov, Nikolay; Smirnova, Maria; Lozbenev, Nikolai; Levchenko, Ekaterina; Gribov, Vasiliy; Kozlov, Daniil; Rukhovich, Dimitriy; Kalinina, Natalia; Koroleva, Polina (September 2019). "Soil cover patterns in the forest-steppe and steppe zones of the East European Plain". Soil Science Annual. 70 (3): 198–210. Bibcode:2019SSAnn..70..198K. doi:10.2478/ssa-2019-0018. ISSN 2300-4975.
  14. ↑ Yerofeyev, Ivan Alekseyevich (30 November 2025). "Ukraine". Britannica. Retrieved 1 December 2025.
  15. ↑ Michalyna, W.; Rust, R. H. (November 1984). "Influence of drainage regime on the chemistry and morphology of some Manitoba soils: clayey chernozemic and gleysolic soils of the Red River Plain". Canadian Journal of Soil Science. 64 (4): 605–20. Bibcode:1984CaJSS..64..605M. doi:10.4141/cjss84-061. ISSN 1918-1841.
  16. ↑ Ba, Zhidan; Wang, Jingfa; Song, Chunwei; Du, Huishi (July–August 2022). "Spatial heterogeneity of soil nutrients in black soil areas of Northeast China". Agronomy Journal. 114 (4): 2021–6. Bibcode:2022AgrJ..114.2021B. doi:10.1002/agj2.20985. ISSN 1435-0645. Retrieved 1 December 2025.
  17. ↑ McQueen, K. G. (October 1994). The Tertiary geology and geomorphology of the Monaro: the perspective in 1994 (PDF). Canberra, Australia: Centre for Australian Regolith Studies. ISBN 9780858894365. Retrieved 1 December 2025.
  18. ↑ "Ukraine lifts ban on sale of farmland in bid to receive international funds". Euronews. 31 March 2020. Retrieved 1 December 2025.
  19. ↑ Kraznozhon, Leo (9 November 2011). "Black market for rich black earth". Kyiv Post. Retrieved 1 December 2025.
  20. ↑ "Correlation of Canadian Soil Taxonomy with other systems". Agriculture and Agri-Food Canada. 17 July 2013. Retrieved 1 December 2025.
  21. ↑ Lomonosov, Mikhail Vasil’evich (1 July 2012). On the strata of the Earth (1763). A translation of О Слояхъ Земныхъ by Stephen M. Rowland and Slava Korolev. Boulder, Colorado: Geological Society of America. p. 24. doi:10.1130/SPE485. ISBN 978-0-8137-2485-0. Retrieved 2 December 2025. And so, there is no doubt that black soil is not primordial matter, but that it has been produced by the decomposition of animal and plant bodies over time
  22. ↑ Geikie, Archibald (1875). Life of Sir Roderick I. Murchison, based on his journals and letters (PDF). Vol. 1. London, United Kingdom: John Murray. Retrieved 3 December 2025. I end, therefore, in believing that this black earth is the last covering of mud and slime which was left by the retirement of the Liassic sea, and was to a great extent derived from the wearing away of the shales of the Jurassic strata
  23. ↑ Fedotova, Anastasia A. (August 2010). "The origins of the Russian chernozem soil (black earth): Franz Joseph Ruprecht's 'Geo-Botanical Researches into the Chernozem' of 1866" (PDF). Environment and History. 16 (3): 271–293. Bibcode:2010EnHis..16..271F. doi:10.3197/096734010x519762. JSTOR 20723789. Retrieved 3 December 2025. The geologist Karl Eduard von. Eichwald, who worked at Dorpat University in Russian Livonia, connected the origins of chernozem with lake sediments
  24. ↑ Krasilnikov, Pavel; Sorokin, Aleksey. "Classification of black soils, chernozems and chernozem-like soils" (PDF). International scientific conference "Eastern European chernozems 140 years after V. Dokuchaev", 2–3 October 2019, Chisinau, Moldova. Retrieved 3 December 2025. Before this publication black soils of South-Eastern Europe were regarded either as marine sediments (e.g. the theories of R. Murchinson and A. Petzgold) or dried peat lands (e.g. E.I. Eichwald, F.F. Wangenheim and some others)
  25. ↑ Fedotova, Anastasia A. (August 2010). "The origins of the Russian chernozem soil (black earth): Franz Joseph Ruprecht's 'Geo-Botanical Researches into the Chernozem' of 1866" (PDF). Environment and History. 16 (3): 271–293. Bibcode:2010EnHis..16..271F. doi:10.3197/096734010x519762. JSTOR 20723789. Retrieved 3 December 2025. Thus, the chernozem was of steppe origins, not forest or peat as had been assumed by most scientists prior to his researches
  26. ↑ Dokuchaev, Vasily Vasilyevich (1879). Tchernozéme (terre noire) de la Russie d'Europe (in French). Saint Petersburg, Russia: Société Impériale Libre Économique. Retrieved 4 December 2025.
  27. 1 2 Eckmeier, Eileen; Gerlach, Renate; Gehrt, Ernst; Schmidt, Michael W.I. (15 May 2007). "Pedogenesis of chernozems in Central Europe: a review". Geoderma. 139 (3–4): 288–99. Bibcode:2007Geode.139..288E. doi:10.1016/j.geoderma.2007.01.009. Archived (PDF) from the original on 8 March 2016. Retrieved 4 December 2025.
  28. ↑ Schmidt, Michael W. I.; Skjemstad, Jan O.; Jäger, Cornelia (December 2002). "Carbon isotope geochemistry and nanomorphology of soil black carbon: black chernozemic soils in central Europe originate from ancient biomass burning". Global Biogeochemical Cycles. 16 (4): 70-1 – 70-8. Bibcode:2002GBioC..16.1123S. doi:10.1029/2002GB001939. S2CID 56045817. These data challenge the common paradigm that chernozems are zonal soils with climate, parent material and bioturbation dominating soil formation, and introduce fire as a novel, important factor in the formation of these soils
  29. ↑ Eckmeier, Eileen (2007). Detecting prehistoric fire-based farming using biogeochemical markers (Thesis). Zurich, Switzerland: University of Zurich, Faculty of Science. doi:10.5167/uzh-3752. It is now an open question as to whether Neolithic settlers did indeed prefer to grow crops where chernozems occurred or if Neolithic burning formed the chernozemic soils
  30. ↑ Eckmeier, Eileen; Gerlach, Renate; Gehrt, Ernst; Schmidt, Michael W.I. (15 May 2007). "Pedogenesis of chernozems in Central Europe: a review". Geoderma. 139 (3–4): 288–99. Bibcode:2007Geode.139..288E. doi:10.1016/j.geoderma.2007.01.009. Archived (PDF) from the original on 8 March 2016. Retrieved 4 December 2025. magnetic susceptibility of soil material may reflect past fires
  31. 1 2 Jordanova, Neli, ed. (2017). "The discriminating power of soil magnetism for the characterization of different soil types". Soil magnetism: applications in pedology, environmental science and agriculture. Amsterdam, The Netherlands: Academic Press. pp. 349–65. doi:10.1016/B978-0-12-809239-2.00008-5. ISBN 978-0-12-809239-2. Retrieved 4 December 2025. Chernozem soils exhibit similar features worldwide and are generally characterized by significant magnetic enhancement in the upper soil horizons
  32. ↑ Nørnberg, Per; Schwertmann, Udo; Stanjek, Helge; Andersen, Tom; Gunnlaugsson, Haraldur Páll (March 2004). "Mineralogy of a burned soil compared with four anomalously red Quaternary deposits in Denmark". Clay Minerals. 39 (1): 85–98. Bibcode:2004ClMin..39...85N. doi:10.1180/0009855043910122 (inactive 4 January 2026). S2CID 129974901. Retrieved 4 December 2025.{{cite journal}}: CS1 maint: DOI inactive as of January 2026 (link)
  33. ↑ Schaetzel, Randall J. (September 1991). "Factors affecting the formation of dark, thick epipedons beneath forest vegetation, Michigan, USA". European Journal of Soil Science. 42 (3): 501–12. Bibcode:1991EuJSS..42..501S. doi:10.1111/j.1365-2389.1991.tb00426.x. Retrieved 4 December 2025.
  34. ↑ Rodionov, Andrej; Amelung, Wulf; Peinemann, Norman; Haumaier, Ludwig; Zhang, Xudong; Kleber, Markus; Glaser, Bruno; Urusevskaya, Inga; Zech, Wolfgang (September 2010). "Black carbon in grassland ecosystems of the world". Global Biogeochemical Cycles. 24 (3) GB3013. Bibcode:2010GBioC..24.3013R. doi:10.1029/2009GB003669. ISSN 0886-6236.
  35. ↑ Vysloužilová, Barbora; Ertlen, Damien; Schwartz, Dominique; Šefrna, Luděk (22 June 2016). "Chernozem. From concept to classification: a review". AUC Geographica. 51 (1): 85–95. doi:10.14712/23361980.2016.8. ISSN 0300-5402.

Further reading