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Biomes and Regions of Northern Eurasia
Steppe and Forest-steppe
<<< Anthropogenic Transformation of Steppe
and Forest-steppe | Biomes & Regions Index | The Future of the Steppe >>>
Issues and Problems of Development
Overexpansion of Arable Agriculture
Although the modern structure of land use is a result of the long history of
development, the greatest influence has been exerted by certain socioeconomic factors of
the Soviet period of which state landownership, establishment of large-scale state farms,
housing policies, and the development of irrigation are the most important. Perhaps the
most drastic transformation of the steppe landscape occurred between 1954 and 1960 when in
the course of the Virgin Land project 418000 km2 of virgin steppe was brought
into agricultural production in the Transvolga region, Southern Siberia, and northern
Kazakhstan and 3 million people migrated into the area to provide labour. In order to meet
the nation's food need quickly, large-scale fields were ploughed and planted using heavy
machinery. Massive overexploitation of land occurred as not only the best soils but also
soils ill-suited for cultivation (sandy, stony, and saline soils) were developed. In the
following years, national yields of wheat increased and in this sense the project achieved
success, albeit more limited than was expected. The effects on the steppe environment,
however, were adverse. The frequency of wind erosion and dust storms increased
dramatically, the runoff in small rivers declined by 40-50 per cent and productivity of
pastures and hayfields in the adjacent areas of the Transvolga region decreased by a
factor of 2.5-3 (Chibilyov, 1992).
Large-scale production undoubtedly proved damaging and the optimization of structure of
arable land is required. Measures aimed at this should involve: introduction of the
optimal sizes of arable and irrigated fields; usage of lands best suited for the given
agricultural practice; diversification and finding the optimal combination of various
types of agricultural activities; and development of agricultural ecosystems which can
easily adjust to the natural bioclimatic conditions without exhausting the agricultural
potential of the landscape. The single most important measure should be the reduction in
arable land and particularly the withdrawal of marginal lands from cultivation. In the
past, cultivation of stony, gravely, and saline soils and already eroded slopes led to
widespread aridization (desertification).
Aridization is particularly an issue in the southern steppe and semi-deserts. It is
manifested in the intensive development of erosion, decline in the contents of organic
matter, reduction of the above ground phytomass, and the changing radiation budgets of
soils. A distinct indicator of aridization is the northward advance of the distribution
areas of semi-desert and southern steppe insects (e.g., the locust), birds (e.g., the
Demoiselle crane), and plants such as Festuca and Stipa kssingiana.
The Grazing Capacity of Pastures
Unanimously researchers agree that steppe ecosystems have formed under the influence of
grazing livestock. Grazing has always had both beneficial and detrimental effects on
pastures. In intensively grazed pastures, degrading effects of overgrazing occur which,
notwithstanding what original types of vegetation association dominated, include a
reduction in number of species, mechanical disturbance of soils, and invasion of
unproductive species such as ephemerals, emphemeroids, and plants adapted to high
concentrations of nitrogen (particularly perennial weeds).
The effects of overgrazing on ecosystems have been a focus of research in Russia since
the beginning of the 20th century (Vysotsky, 1915; Pachosky, 1917; Alekhin, 1934; Evseev,
1954; Ivanov, 1958; Gorchakovsky and Ryabinina, 1984; Chibilyov, 1992). However, it is
difficult to correlate these results and assess the issue for the whole of Northern
Eurasia because of the vastness of the area and the different timing of research. Thus in
the 1950s, Ivanov (1958) distinguished five stages of pasture degradation in western
Kazakhstan, showing that the productivity of pastures declined from 1.35 kg m-2
(undisturbed pastures) to 0.12 kg m-2 (permanent damage). Similar data were
obtained later by Gorchakovsky and Ryabinina (1984) for the southern Urals. They
distinguished four stages of pasture degradation and reported declines in productivity
from 1.4 kg m-2 to 0.3-0.2 kg m2. The detrimental effects of
overgrazing are notoriously persistent and it takes a considerable length of time for
pastures to recover.
Plate 11.3 Steppes as pastures (photo: A. Chibilyov).
The timing of grazing is particularly important for steppe ecosystems. Especially
damaging is grazing in spring, when soils are still wet after snow melt. Mechanical
pressure of hooves on soil disturbs it, causes compaction and damages plants. Soil
crusting, rapid loss of moisture from soil and loss of valuable fodder species follow.
Early grazing is widely practised in the southern steppes of the Volga region and southern
Urals because of the shortage of forage in winter.
A number of measures have been proposed to use pastures in a more sustainable way and
to restore those that are damaged. These include: evaluation of pasture capacities and
compliance with the established norms of grazing; improving winter forage supply and
prohibition of early spring grazing; introduction of recovery periods for pastures instead
of using them by different livestock; and improving productivity of pastures through
mulching, application of fertilizers, and artificial sowing of sedges and leguminous
plants. The introduction of pasture management began in the Transvolga region, Southern
Siberia and northern Kazakhstan in the 1980s when livestock numbers peaked. After 1992, a
decline in stock occurred. In some regions of Kazakhstan stock numbers decreased by a
factor of 2.5-3 and in the Transvolga and southern Urals by a factor of 1.5-1.8. The area
of arable land was also reduced, encouraging the formation of fallow soils which are often
used for grazing. However adverse the economic effects of agricultural decline were,
pastures received a much needed recovery period and the problem of overgrazing has become
less pressing.
Irrigation
Although the most intensive development of irrigation occurred in the desert and
semi-desert zones, and particularly in Central Asia, steppe also accommodates a number of
large projects. The most unfortunate aspect of irrigation development is that little
distinction was made between irrigating desert and steppe soils. Norms of water supply,
originally proposed for the arid regions, were introduced ignoring the fact that climate
and weather in steppes are different and, unlike in deserts, dry and wet years and spells
alternate and so does the moisture contents of soils. Similar to the infamous irrigation
projects of Central Asia, irrigation practices used in the steppe are rudimentary with
canals unlined, pipes leaking, and return flows not collected properly. The attempt to
supply water to chernozems has had a very damaging effect because natural to these soils
are a seasonal moisture deficit and a succession of wet and dry years. Instead of
improving the quality of chernozems, irrigation has caused a substantial loss of organic
matter, a rapid rise of the ground water table, waterlogging, salinization, and the
development of erosion. In almost every chernozem region where irrigation was practised,
there are examples of abandoned fields that originally had a high quality but then became
degraded because of irrigation. By 1987, in Russia's steppes alone, 606000 hectares of
arable chernozems had been withdrawn from agricultural use (Egorov, 1989). Particularly
damaged were soils in the Rostov and Saratov regions. The 10-15 year history of irrigation
of chernozems in the Northern Caucasus has led to a twofold increase of salts in the
uppermost metre of the soil (Shipunov, 1988).
Researchers, concerned with the effects of irrigation on chernozems, suggest that
irrigation practices in the steppe regions should change and in future be based on the
following principles: irrigation should be limited to periods of droughts and norms of
water supply should be adjusted to weather conditions; water losses to soil should be
reduced by lining canals and furrows; and the ground water table should be maintained at a
depth of 5-6 m (Rozanov, 1983). However, the best solution may be to keep the irrigation
of chernozems to a minimum while introducing alternative methods to improve agricultural
productivity (Chibilyov, 1992).
Agroforestry
The naturally low woody cover of steppes and the deforestation by humans in the past
influenced scientists and agronomists to consider reforestation and agroforestry as
measures to improve the climate and water balance in the steppe and forest-steppe. This
work was pioneered at the end of the 19th century by Vasily Dokuchaev. In 1892, working
for the State Forestry Department, he established three experimental plots each covering
50 km2 in the Voronezh, Kharkov, and Yekaterinoslav (now Dnipropetrovsk)
provinces with the purpose of developing agromelioration and agroforestry (Dokuchaev,
1895). The major idea was that belts of trees (termed shelter-belts) planted around arable
fields improve moisture retention by soils and protect fields from dry winds which are one
of the major climatic hazards in the region. Later, in the 1920s, following severe
droughts in the southern East European plain, the Russian government adopted a series of
measures aimed at combating the adverse effects of droughts, emphasizing once again the
importance of reforestation and agroforestry. By 1941, about 5000 km2 of
shelter belts and protective woodlands had been established across the FSU and by 1953
another 23000 km2 had been planted. Today, these woodlands have the same
ecological, cultural, and recreational functions as natural woodlands. They have also
proved helpful in the improvement of microclimate, productivity of agricultural ecosystems
(through a more favourable climate and by harbouring birds who feed on pests and weed
seeds), and regeneration of damaged landscapes. By providing habitats for animals and
birds, they improve biological diversity of the steppe and forest-steppe.
Although agroforestry proved extremely successful in the steppe and forest-steppe
regions, the completed agroforestry systems are still lacking in the steppes of Russia and
even more so in the steppes of Kazakhstan. Even in the Kamennaya Steppe in the Voronezh
region, where one of the Dokuchaev's experimental plots is located, shelterbelts and
protective forests around fields occupy less than 1 per cent of all arable land, although
the area required is 2.2-2.5 per cent. Only 11 per cent of the shelterbelts needed to
prevent gullies from expansion has been established (Shipunov, 1988). Essential to the
agroforestry practice is its complete implementation so that it can function as a
landscape system in which a balance between various types of woody cover and arable land
is achieved (Chibilyov, 1992).
Restoration of Fauna
Before the advent of arable agriculture, steppe and forest-steppe biomes had a rich
fauna. According to Mordkovich (1982), the stock number of large (such as marmot) and
larger mammals exceeded one billion. There were also a few hundred million large birds.
The potential of steppe vertebrates to adapt to the transformation of habitats, caused by
humans, varies. Crops provide some species (e.g., ground squirrel, common hamster, rook)
with additional food supplies and their populations have increased in marginal lands and
pastures. Shelterbelts and protective woodlands provide habitats for other species (elk,
roe deer, hawk, woodpecker) who migrate to the steppe from the north. However,
agricultural development has had a detrimental effect on most species. Due to the
widespread loss of habitat, the distribution areas of many species have diminished,
population has been depleted and locally some species (great bustard, tawny eagle) have
become extinct.
There are, however, signs that that there is still a potential for the restoration, at
least partial, of fauna in the forest-steppe and steppe. Research, conducted in northern
Kazakhstan and the southern Urals in the 1970s — l980s has shown that across large areas
marmots have begun to adapt to the transformed habitats (Dezhkin, 1987 a, b; Bibikov,
1989). In the Karaganda region of Kazakhstan, the average population density of marmots
within the 300 m of an arable field varies between 17 and 21 animals per km2
compared to 25 in the pristine steppe (Kapitonov, 1987) while in the Orenburg region its
population in close proximity to fields reaches 28-35 (Chibilyov, 1992). Since the early
1980s, the population of the little bustard has been increasing in the steppes of
Transvolga and the Urals while an increase in the population of the great bustard has
occurred in the Transvolga areas of the Saratov region (Khrustov et. al., 1997).
Forestation and reforestation, construction of reservoirs, and diversification of land use
in comparison with the previous decades reduce pressure on the steppe inhabitants and
provide at least some opportunity for the restoration of the steppe and forest-steppe
fauna.
Nature reserves and research institutions are also concerned with the restoration of
biological diversity. There has been much success in the restoration of the stock of
saiga. The population of the Asiatic wild ass (Kulan), the restoration of which began in
1941 in the Badkhyzsky nature reserve in southern Turkmenistan, has now reached 2000
individuals (Chibilyov, 1990). Attempts are now being made to restore the population of
auroch and the wild horse.
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