What is the soil in the forest? Type, features
Forest-steppe is a natural zone, located between the steppe and forests. She stretched across the East European Plain. Also, this species is found in the West Siberian Plain and the Southern Urals. Separate areas of forest-steppe are within the limits of the Central Danube Plain, on the territory of Mongolia, the Far East, and Northern Kazakhstan. The soil of the forest-steppe is often gray, forest, with a different composition.
The forest-steppe zone stretches in a discontinuous strip from west to east. Chisinau, Cheboksary, Voronezh, Saratov, Ufa are located in this zone. Further, the forest-steppe are interrupted and renewed again from Troitsk to Barnaul. Forest-steppe soil occupies more than sixty million hectares of the entire territory of the Russian Federation. About half of these lands are arable land. In the forest-steppe, gray forest and forest-steppe soils are located, located under the forests and on the borders of forests and steppes, and on the steppe areas - mainly podzolized soil types, but also black soil.
The climatic conditions of the forest-steppe zone have much in common, although when comparing individual areas of the territory are different. This zone is characterized by low precipitation, but evaporation is higher than in the forest zone. Most rains occur in the summer.
In the forest-steppe dry winds and droughts are observed. In the western part of the rain comes more than in the east. The same applies to temperature: in the west it is warmer than in the east, by about three degrees. The growing season is also different: in the west, plants develop about 250 days a year, and in the east - only six months. The rest of the time is for a period of rest.
Climatic conditions have a great influence on the soil composition of the forest-steppe, as well as on the composition of the flora and fauna. In the European part there are deciduous forests, and in Siberia - birch. They do not form large arrays, but grow in small pegs, which include birch and willow.
Features of the forest-steppe zone
After long-term studies, scientists were able to identify that the boundary of forests does not remain constant, not only because of man’s fault, but also because of climatic changes taking place on Earth.As a result, there is a change of woody type of vegetation on the steppe and vice versa. Timothy grass, oats, alfalfa, peas, feather grass and other grasses are common in open areas that are preserved in protected areas and along forest edges.
The forest-steppe zone has a special relief: there are irregularities, hills, ravines and beams. Characteristic for the area saucer-shaped slide. The peculiarity of soil formation in forest-steppe is their diversity. In these zones there are sands, sandy loams, loam, moraines. On the territory of Siberia, the soil is alkaline, and at a certain depth it is underlain by salt-bearing marine sediments.
Gray land of forest-steppe
Similarly, no one scientist can say when and how the soil of the forest-steppe was formed. V. Dokuchaev became the founder of soil science, which singled out this zone as a separate group of gray lands. It was he who proposed to distinguish gray forest soil types.
V. William considered the formation of gray soils as a result of the weakening of podzolization and the enhancement of the turf soil formation process. Scientists have managed to prove that it is in the forest-steppe that favorable conditions are forming for the formation of gray soil.
Russian scientists in most cases confirm the point of view of V. William.In the zone of forest-steppe there is a process of changing small-leaved, coniferous plants to deciduous. This area is characterized by maples, ash, hornbeam, oak and other types of trees. Under their crowns grow only those types of grassy plants that are very demanding on the composition of the soil.
If we compare the properties of the soils of forest-steppe with deciduous forests and conifers, then there is a huge amount of calcium, magnesium and silica just under ordinary deciduous trees. In areas with coniferous forests, these elements in the ground are 2-3 times smaller.
A huge amount of food is in the grassy plants that grow under the oaks and other types of trees. And taking into account that precipitation falls in the summer period and as much as it has evaporated, then unique conditions are created for the reproduction of beneficial microorganisms that mineralize the organic matter of the soil. A large amount of humic acids and fulvic acids is formed in the humus. Calcium and magnesium are fixed in the upper part of the earth in the form of humus.
Layers of forest-steppe soil
The type of soil in the forest-steppe is formed as a result of podzolization. The following layers are formed:
- A0.It is a layer of forest litter, about three centimeters thick, consisting of leaves and plant residues.
- A1. This layer is loose, friable, grainy, gray shade, its thickness is about fifteen centimeters.
- A2. It contains an admixture of humus with a large amount of silica powder. This layer is about thirty centimeters, light gray.
- IN 1. At a depth of more than thirty centimeters is brown soil with organic compounds.
Forest steppes soil subtypes
And what kind of soil prevails in the forest-steppe and which subtypes exist? All forest-steppe soils are divided into three groups according to the type of podzolization. Among them there are gray, light gray and dark gray lands.
In light gray soils, the podzolization process is very pronounced, and in dark gray soils it fades.
By chemical composition, gray lands have an acidic or slightly acidic reaction and medium saturation with organic and mineral microelements.
Dark gray soils in their composition have a richer composition: here there is more humus, humic acids, calcium and other useful elements. Scientists have identified an unusual pattern: from north to south and from west to east, the content of humus in gray soils increases.
Gray Forest Land Classification
Knowing what the soil in the forest-steppe, scientists were able to classify it. According to the conditions of soil formation, gray lands are divided into West Siberian, Southern European, Western, Eastern Siberian, Eastern European. In these areas, the composition of the soil is different, there are also different amounts of precipitation, different temperatures. The gray soils themselves are subdivided into gray, light and dark gray forest soils.
The light-gray soil types of the northern regions are similar to sod-podzolic. But there is no podzolic horizon in the gray lands, there is a lot of humus here. In the dark gray lands all layers are colored with humus.
According to their kind, gray forest lands are divided into usual, boiling, residual-carbonic, dark-colored earths at the bottom of the humus layer, contact-gleyish, lands with the second humus horizon.
Gray lands are considered to be the most developed, since about fifty percent of arable land is concentrated on them, five percent is occupied by hayfields, and less than a percent is allocated for pastures and pastures. On the gray lands they grow bread, beets, potatoes, flax and other crops. On light gray soils, plant cultivation is not practiced due to the high acidity of the earth.To increase the level of fertility, such lands lime up, and also make large portions of nitrogenous and phosphorus-potassium fertilizers.
Coniferous and small-leaved trees usually grow on light gray lands. Gray and dark gray lands are more productive, because of which broad-leaved trees and plants demanding on certain soil compositions grow on these soils.