Forest-steppe soils: types and their properties, formation conditions and characteristics

The forest-steppe zone mainly has a flat relief, which is distinguished by small elevation changes and a slight slope of the terrain. It is also characterized by the presence of ravines. There are many varieties of forest-steppe soils, each of which has certain characteristics. The main types of soil include gray forest, meadow chernozem, leached and podzolized chernozem.

General soil characteristics of the forest-steppe

The main property of the forest-steppe zone is considered to be an intermediate character between forests and steppes. In such an area there are wooded fragments and characteristic steppe elements.Toward the north, such a zone is more reminiscent of a forest. In these regions, favorable conditions are being created for the formation of black earth soils.

The climate of the forest-steppe has significant differences from the forest zone. This is due to the more southerly location. The growing season takes longer, while the amount of precipitation, on the contrary, decreases. In the west it is 500 millimeters, in the east - 300. The air temperature in the forest-steppe is higher. Evaporation and dryness of the air also increase. All of these features are considered key factors in soil formation.

Forest-steppes of Eurasia are common from the Carpathians to Altai. There is this zone in North America. It is present in the northern United States and southern Canada. It is characterized by a flat relief. At the same time, strong slopes are quite rare.

The soils of the forest-steppe are diverse. In this natural area, the following types of soils are almost always found:

grey forest soils with manifestations of podzolic processes;
podzolized chernozems;
leached chernozems;
meadow chernozems;
chernozem-like prairie soils.

In general, the soils of the forest-steppe are characterized by the following features:

significant thickness of the humus horizon;
weak mineralization of plant residues;
presence of alkaline and solonetzic zones in regions with a pronounced continental climate;
strength of internal structure;
high degree of fertility;
possibility of intensive processing;
no need to comply with strict restrictions during agricultural work.

Difference from steppe soils

In the steppe zone, the amount of precipitation is significantly reduced, and the volume of evaporation, on the contrary, increases significantly compared to the forest-steppe. This has a direct impact on the average humidity parameters, vegetation characteristics, the nature of accumulation and modification of plant remains.

The forest-steppe is characterized by gray forest soils, which are mainly formed in areas occupied by broad-leaved forests. In such regions, crop plants often face severe moisture shortages.

In the steppes, the soil is considered to be drier. However, in these natural areas there is much more high-quality black soil.

Common types

Forest-steppe is characterized by different types of soil, each of which has certain characteristics.

Greys

The distinctive features of these types of soil are associated with the climate of a particular area. In the west of the forest-steppe, relatively high humidity is observed. However, as you move east, the continentality of the climate becomes more pronounced.

Products of weathering to which the upper layers are exposed, due to the natural movement of substances, penetrate into the lower structures. They can also get into the original parent rock. The roots of plants that are in the gray forest-steppe soil absorb many valuable elements.

Substances that are formed as a result of the vital activity of plants are mainly deposited in the upper horizons. Therefore, the formation of turf is considered more active than the folding of podzol.

Gray zonal soils are subject to pronounced claying. Silty fragments mainly accumulate at the level of the illuvium. The development of the humus horizon is characterized by high thickness. In this case, there are no special problems.

Light gray

As a rule, this type of soil corresponds to the highest areas of the terrain. It is not always possible to distinguish it from soddy-podzolic soil. However, a deeper study reveals a developed illuvial horizon. The transfer of silty fragments between it and the soil surface is 15-25%. Light gray forest-steppe zones often include light loams and sandy loams.

Other important features include:

variation of arable mass density - 1.2-1.4 grams per 1 cubic centimeter;
density of the washout layer - 1.5-1.7 grams per 1 cubic centimeter;
moisture accumulation - maximum 150-180 millimeters per 1 meter;
almost no structure;
tendency to form thick crusts.

Dark gray

This type of soil is very rare in the forest-steppe. As a rule, its appearance is associated with the boundaries of the high right banks of rivers - most often on depressions. Soil saturation with podzol is relatively low. However, the accumulation of humus is quite active.

Internal migration of colloids in the soil structure is limited. The structure of the soil is clearly expressed. However, when moisture enters, it is quickly lost. The humus content in the arable layer is not less than 2% and not more than 4.9% of the total mass.

The coefficient of hydrolytic acidity can reach 1-3.7 equivalent milligrams per 0.1 kilogram of soil. The volume of bases is 80-95% - the specific amount depends on the conditions.

Gray types of soil are more common in the northern regions of the forest-steppe. In the south of this zone, chernozems with a high content of podzol, leached soils and typical chernozems are predominantly found.

Vegetation

The natural vegetation of this zone includes small forests that alternate with areas of steppe meadows. In the European part of the forest-steppe, oaks and lindens are most often found. In the west, the main species are ash and hornbeam. Pine, birch, and larch mainly grow in Siberia.

In the northeast region of China, the main part of the vegetation is oaks and other broad-leaved species. The forest-steppe of North America is characterized by birches, oaks, aspens. Hazel also grows there.

Natural grasses are left only in national parks. They include turf grasses and weeds. There are 70-80 species of terrestrial plants per 1 square meter. Meadow grasses, feather grass, fescue, reed grass predominate in North America.

Agricultural use

Forest-steppe soils are often used for agricultural purposes. At the same time, it is important to carry out a number of activities aimed at increasing their productivity.

Events

Forest-steppe zones are often accompanied by droughts and winds that lead to severe erosion. That is why it is so important to carry out the following activities:

eliminate drought and the effects it causes;
eliminate wind erosion risks;
improving the quality of alkaline soils;
weed control.

When planting spring plants, it is important to strictly observe the deadlines. They are determined depending on the biological characteristics of the varieties. In this case, different types of crop rotation are important. They are grain-fallow, grain-rowed, grain-fallow-herbal.

Productivity increase

Choose reclamation techniques is required very strictly. In doing so, it is important to prevent a flushing form of water circulation. It is forbidden to allow the rise of groundwater. Of no small importance is the minimization of fluid filtration losses. If necessary, it is permissible to equip a special drainage.

Quality irrigation can only be carried out with the help of modern systems. Reducing surface runoff is achieved by autumn plowing. Planting alfalfa and other perennials is recommended to protect annuals.

Forest-steppe soils are also subject to negative agrogenic impact. Big risks are associated with growing crops and grazing livestock.

The use of mineral and organic supplements has now decreased by several dozen times. However, this led to a significant difficulty in restoring the quality of the soil. Aggressive plowing provokes rapid depletion of plant crops and disrupts flow patterns.

The following crops are mainly grown in the forest-steppe zone of Russia:

vika;
peas;
winter and spring wheat;
vegetable crops;
winter rye;
buckwheat;
millet;
rapeseed;
sunflower;
corn;
hemp.

Humus content

Forest-steppe soils contain a lot of humus. To the north and south of this strip, the parameters decrease. At the same time, fertility indicators depend on the specific type of soil. These values are presented in the table: tons per 1 ha

Dark gray forest 296 452 549 Typical thick black soil709 Common black soil426

	Podzolized black soil
	Leached black soil

Soil characteristics change not only from north to south, but also from west to east. An increase in the continentality of the climate towards the eastern part leads to an increase in the content of humus in the soil. At the same time, the thickness of humus horizons decreases.

Forest-steppe soils are diverse and have many features. They must be taken into account in the case of the use of soils for agricultural purposes. Of great importance is the holding of special events aimed at improving the quality of the soil.