World’s Soil Resources

Boreal forest/taiga
These ecosystems cover extensive areas in northerly latitudes and with low annual temperatures. There are
large expanses in central and eastern Russia, with medium precipitation of 40-100 cm yr -1 , partly in the form
of snow. Predominant tree species are coniferous including Abies, Picea, Larix and Pinus as well as deciduous
such as Betula spp. And Populus spp. The ground cover is mainly dominated by mosses and lichens. These
biomes are known for slow regeneration of mature forests, due to the challenging climate and soil conditions.
Forests are sensitive to acid rain and other forms of pollutant. Agriculture in the taiga is restricted to relatively
small areas used for livestock and production of such crops as rye, flax, millet and vegetables. Some two
decades ago, soil acidification induced by industrial contamination of the atmosphere, so called ‘acid rain’,
was an important menace to soil quality in these areas. However, today the pressure of technogenic acid
precipitation is considerably reduced (Jones et al., 2011).
Broad-leaf and mixed forest zone
This zone stretches across the European region from the British Isles to Western Siberia, and most of
this territory is actually under cultivation. In the temperate climate, forests experience a wide variability in
temperature and precipitation. Species such as oak (Quercus spp.), beech (Fagus spp.), birch (Betula spp.)
and maple (Acer spp.) typify the composition of this biome. Structurally, these forests are characterized by
four layers: a canopy composed of mature full-sized dominant species; a slightly lower layer of mature trees; a
shrub layer; and an understory layer of grasses and other herbaceous plants. In contrast to tropical rain forests,
most biodiversity is concentrated much closer to the forest floor. The zone has a favorable humid climate and
soils with a relatively high natural productivity. Anthropogenic pressure is, however, strong due both to the
intensive practice of agriculture and to high population density. The main threats to soils in this zone are water
erosion favoured by intensive deforestation, and soil sealing and capping due to the high urbanization rate
and dense infrastructure. In addition, the high degree of industrialization in this biome results in extensive
contamination of the soils.
Temperate coniferous forest
This ecosystem is also known as ‘temperate evergreen forest’. It sustains the highest levels of biomass of
any terrestrial ecosystem after tropical rainforest. The area has warm summers and cool winters, resulting
in a high variation of the vegetation, e.g. needle leaf trees, broadleaf evergreen trees or a mix of both types.
Temperate evergreen forests are common in the coastal areas of regions with mild winters and heavy rainfall,
or inland in drier climates or hilly areas. Predominant tree species include pine, cedar, fir and redwood. This
biome is mostly located in mountainous regions and the use of these areas is not very intensive.
Temperate grassland zone
This zone possesses the soils with the highest natural productivity such as Chernozems and Kastanozems.
This high potential results in an intensive use of the land for agriculture which in places occupies up to 90-95
percent of the total land area. The main threats to soils in this zone are water and wind erosion. These processes
are the main reasons for the loss of organic carbon in soils; however, the loss of carbon by mineralization from
arable lands is also a common process. Since the population density and the development of industry are high
in this zone, soil sealing and capping and contamination are also threats. In places, especially in endorheic
valleys, soil salinization may be observed.
Status of the World’s Soil Resources | Main Report Regional Assessment of Soil Changes
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in Europe and Eurasia