Physical Geography
  Tectonics and Geology
  Climatic Change
  Climate at Present and in the Past
  Rivers, Lakes, Seas and Wetlands

Biomes & Regions
  Arctic Environments
  Boreal Forests
  Mixed and Deciduous Forests
  Steppe and Forest-steppe
  Arid Environments
  The Mountains of Northern Russia
  The Mountains of Southern Siberia
  The Caucasus
  The Mountains of Central Asia
  Lake Baikal
  The Far East

Environmental Problems
  Radioactive Contamination
  Oil and Gas Development
  Air Pollution
  The Aral Sea Problems
  Deforestation and Degradation of Forests
  Nature Protection and Conservation

Images of Russian Nature
  Geographic Index
  Systematic Index
  Alphabetical Index

Nature Reserves
  Northern Russia
  Central Russia
  Povolzhye (Volga river basin)
  Southern Russia
  Ural Mountains
  Western Siberia
  Eastern Siberia
  Far East

‘отографии природы –оссии
  √еографический каталог
  —истематический каталог
  јлфавитный каталог

Nature Landscapes of the World
  North America
  South America

Field Ecology Education
  Instructive Videos
  Instructive Manuals

—качать наши приложени€ из магазина RuStore
—качать наши приложени€ из магазина RuMarket —качать приложени€ Ёкосистемы из магазина NashStore
—качать приложени€ Ёкосистемы из магазина GetApps Xiaomi
—качать приложени€ Ёкосистемы Ёко√ид из магазина Google Play / Play Market
—качать приложени€ Ёкосистемы Ёко√ид из AppStore / iTunes

Bird Decoys for European Birds: Songs, Calls, Sounds, Bird voices - application for Android download from Google Play / Play Market for free

Share this page with your friends:

( ) : : = = + +

Russian Nature

Home | Physical Geography | Biomes & Regions | Environmental Problems | Images of Russian Nature | Nature Reserves

Our Field Ecology Center published more than 180 methodical materials for nature studies. Some of them are in English:
Mobile educational application: Ecological Field Studies Techniques on Play.Google Mobile field guide Birds of North America: Songs and Calls Decoys on Play.Google WILD FLOWERS OF RUSSIA Field Identification Guide on Play.Google Mobile field guide Birds of Russia on Play.Google Mobile field guide Birds of Russia Songs, Calls and Voices on Play.Google Mobile field guide Birds of Europe Songs, Calls and Voices on Play.Google Mobile field guide Birds of Europe Songs, Calls and Voices on Play.Google
Mobile Educational Apps and Field Identification Guides for Russian, European and American Birds
Applications for Android and iOS are available at GooglePlay and AppStore

Please put an active hyperlink to our site (www.rusnature.info) when you copy the materials from this page

Physical Geography of Northern Eurasia

Soils of Northern Eurasia

<<< Autonomous and Heteronomous Humid Soils | Physical Geography Index | Autonomous and Heteronomous Arid Soils >>>

Autonomous and Heteronomous Semi-humid and Semi-arid Soils

This group includes soils of the deciduous forest, forest-steppe, and northern steppe biomes. The autonomous soils of this group are grey forest soils and luvic chernozems. Heteronomous soils are usually solods (also known as planosols).

Grey soils or serozems develop under deciduous forests (Figure 4.3) on about 60 million hectares or 2.8 per cent of the total area of the FSU (Rozov, 1968; Simakova et al., 1996).

Distribution of cambisols and grey forest soils

Fig. 4.3 Distribution of cambisols and grey forest soils

This is one of the main agricultural areas of the region and diverse crops are cultivated on grey soils. Grey soils are mostly associated with well-drained hilly plains composed by loess-like carbonate loams. The grey soil's profile has a clear differentiation of clay and total chemical composition by eluvial-illuvial type (Akhryrtzev, 1979). Humic and eluvial horizons are impoverished in iron and aluminium oxides and accumulate carbonates. The accumulation of iron and aluminium oxides and the reduction of silica acid contents are typical of the illuvial ¬ horizon. The reaction of the soil solution changes from weakly acid in the upper part of the profile to neutral and basic in the lower part. Only the upper part is unsaturated by bases. The gley variety of grey soils develops in depressions and weakly drained watersheds on clay deposits (i.e., in conditions of excessive moisture supply).

Luvic chernozems (Figure 4.1) develop mainly on loamy carbonate rocks in well-drained areas of the Russian northern forest-steppe, in Western and Central Siberia, in the foothills of the western Cis-Caucasus and in the forest-steppes of Moldova (Prasolov, 1939; Krupenikov, 1967; Chernozemy SSSR, 1974; Lebedeva, 1996). Luvic chernozems are distinguished by the intensive accumulation of humus and weak eluvial-illuvial differentiation of the profile by clay fraction, physical clay, and total contents of sesquioxides. Morphologically, the eluvial-illuvial differentiation is expressed through the presence of a light flour-like powder in the lower part of the A horizon and the upper part of the ¬ horizon. Soils have a weak acid reaction in the upper part of the profile and have extremely good physical properties due to the excellent water-resistant aggregate structure of their humic horizon.

Types of soils and corresponding vegetation zones in Northern Eurasia

Fig. 4.1 Types of soils and corresponding vegetation zones in Northern Eurasia

Planosols (or solods) occur mainly in the forest-steppe and steppe zones between stretches of grey soils and chernozems, and also locally in the southern steppe and semi-desert zones. They are most typical of the West Siberian forest-steppes. Planosols have a patchy distribution on the plains of northern Kazakhstan and the southern Far East under hydrophilous plant communities. Planosols with differing degrees of salinization occupy about 0.5 per cent of the total FSU territory (Rozov, 1968). They develop on flat poorly drained lands and in isolated depressions covered by vegetation represented by ash, birch, willow, and hydrophilous herbaceous species. Planosols are soils with clearly expressed differentiated profiles. They are distinguished by the presence of carbonates and readily soluble salts in the lower horizons and by distinct signs of gleying across the profile. The upper eluvial part is improverished in compounds of iron, aluminium, magnesium, calcium, sodium, but is relatively enriched by silica. The illuvial horizon has a neutral or alkali reaction and exchangeable sodium (occasionally in large quantities up 10 per cent or more of CEC). These properties are only typical of planosols and distinguish these soils from other clay-differentiated soils such as, for example, podzoluvisols.

<<< Autonomous and Heteronomous Humid Soils | Physical Geography Index | Autonomous and Heteronomous Arid Soils >>>




Recommend this page to your friends:

* *