Grasslands of the World.pdf - Disasters and Conflicts - UNEP

The Russian Steppe 385
winters, precluding arable cropping at the eastern extreme. High latitudes and
absence of moderating maritime influences determine the harsh continental
climate prevalent in Russia . Huge mountain ranges along the southern borders
and Central Asia preclude penetration of maritime tropical air masses. The
Arctic Ocean acts as a snow-covered, frozen mass rather than a relatively warm
ocean influence. As the territory lies in a westerly wind belt, warm influences
from the Pacific Oceans do not reach far inland. In winter a large cold highpressure
cell, centred in Mongolia , spreads over much of Siberia.
In the low-pressure system of summer , warm and moist air pushes from the
Atlantic Ocean well into Siberia. In many areas, however, the summer rainfall
distribution is not always advantageous for agriculture. June and July are often
dry , while rain may interfere with cereal harvest in August. Annual precipitation
decreases from over 800 mm in western Russia to below 400 mm along the
Caspian Sea.
Climate and vegetation fuse in zones that extend across the country in
eastern-western belts. The tundra of the Arctic coast, with its permafrost and
vegetation of mosses, lichens and low shrubs, is too cold for trees. The next (sub-
Arctic) zone is the boreal (coniferous) forest , the taiga , occupying two-fifths of
European Russia and most of Siberia. Much of this region also has permafrost.
Large areas are devoid of trees, primarily because of poor local drainage, and the
vegetation is marshy. The soils of the taiga are podsolic and infertile.
Further south stretches a belt of mixed forest from Saint Petersburg in
the north to the border with Ukraine in the south. The mixed-forest grades
through a narrow zone of forest-steppe before passing into the true steppe.
True steppe, as distinct from the forest -steppe further north, is predominantly
a grass vegetation with a few stunted trees only in sheltered valleys. The
true steppe belt begins along the Black Sea coast, encompasses the western half
of the northern Caucasian plain, and extends northeast across the lower Volga,
the southern Urals and the southern parts of western Siberia.
Together with the forest -steppe, the steppes form the chernozem belt, the
agricultural heartland of Russia . The forest-steppe is black chernozem soil,
high in organic matter (OM) and minerals, and better watered than the steppe.
Steppe soils are somewhat lower in OM, but high in minerals, and many are
also classified as brown-steppe (chestnut).
ECOLOGICAL CLASSIFICATION
In the Russian Federation with its vast uninterrupted plains, zones delineating
the major vegetation types agree conveniently with climatic zones and, in a
way, also with major soil types. Typically, these zones tend to run in semi -
parallel belts in a slightly northwesterly to southeasterly direction.
Topography, watercourses and variation in soil conditions become relevant
at the rayon [a small territorial administrative division] or rather at the (former)
Kolkhoz or Sovkhoz level. It was at this unit level that grassland description