Podzolic soils: characteristics and conditions of formation, fertility, climate

Podzolic soil types correspond exclusively to northern coniferous forests, also called boreal. For the appearance of such lands, cold areas of the terrain are required, which are characterized by an attractive leaching regime. The term "podzol" was coined by Dokuchaev V.V., who has been studying such soils since 1875. The main feature of these types of soil is the high content of silicic acid, which is 85%.

What is this?

The term "podzol" was introduced into science by Dokuchaev V.V. The scientist has been studying these soils since 1875. The word was borrowed from the vocabulary of the Smolensk province.It comes from a practice common to the peasants of that region, in which the first plowing of virgin soil reveals an ash-like layer of soil.

Podzolic soils are understood as the type of soil that has formed under coniferous and mixed forests of the temperate zone on carbonate-free rocks. This is due to the development of the podzolic process. The composition contains 1-4% humus. Such soils are considered infertile.

Podzolic soils are located in a cold and humid climate zone. The maximum number of such lands is found in Russia. Their geographical position falls on the plains and plateaus. This includes the European part of Russia, the Far East, Eastern Siberia.

Also, podzolic soils are found in Western Europe, Canada, and the USA. In addition, they are characterized by Asian and even African location.

Soil-forming rocks include:

• loam and clay soil types;
• sands and sandy loams;
• alluvial and deluvial rocks;
• moraine deposits.

The acidic reaction and the high content of ferrous oxide are considered important characteristics of such soils. Such territories have almost no economic value. For the use of soils, they need to introduce a lot of fertilizers. There are several types of soil associated with different climates.

The structure of such a land looks like this:

• organogenic mass;
• 100-150 millimeters of humus;
• 50-500 millimeters of gleyed horizon;
• 200-500 mm illuvium;
• soil-forming rock - with active moisture, it is subject to gleying.

Formation of podzolic soils

The soil formation conditions of podzolic lands include the following:

• depletion of plant litter in nitrogen and ash substances;
• low temperature;
• slow microbial activity;
• preservation of litter in the form of bedding.

The main area of distribution of such soils is the taiga. It is characterized by a strong decrease in temperatures in winter. In summer, this climate zone is also cool. As a result, little precipitation evaporates. Fallen needles also provide ground moisture retention.

A distinctive feature of the soil is low fertility. The content of humus in such soil is 1-3%. The thickness of the humus horizon reaches 5-15 centimeters.

Profile

Podzolic soils are characteristic of the taiga zone. The humus horizon of podzolic soils is characterized by a whitish or gray-whitish color. In terms of structure, its format might look like this:

• plated;
• scaly;
• leafy-scaly;
• flaky platy.

At the top there is a slightly spread bedding, the layer of which is 5-10 centimeters. Under the humus horizon there is a variegated transition layer. The illuvial level of the brown shade has the brightest color.

Illuvium has a high density and nutty structure. Below, a more prismatic structure is observed. Then soil-forming rocks are formed.

The eluvial layers that form in such soil are typically acidic or strongly acidic. The part of the bases is 20-50%.

Soil relief

Podzolic soil types are located in places with different topography. However, in most cases, the connection with the moraine plains dominates. Most often in such natural areas, ridges, ridges and flat places alternate.

But sometimes podzolic soils are found in the lowlands. At the same time, a key condition in the soil structure is full drainage. It is characterized by low volatility. Almost all lands of this type are not lower than 200 and not higher than 500 meters.

Classification

There are several types of podzolic lands. Each of them has certain features.

Proper podzolic

Such lands are found in areas that include rocks of different types.Most often, such soil is located under the middle taiga forests. Not only coniferous trees grow in these places, but also shrubs, mosses, lichens. The upper horizon is characterized by an acidic reaction. The amount of humus in the structure is 1-7%.

Gley-podzolic

The appearance of such lands is mainly associated with loamy soils or lighter soil types. On the surface of the gley-podzolic land, a typical northern taiga is observed, which includes coniferous and mixed forests. Mosses, lichens, shrubs also grow here. The thickness of the forest floor is no more than 10 centimeters. Below is a podzolic gleyed mass 3-15 centimeters in size.

Sod-podzolic

Such soils are more common in areas with coniferous-broad-leaved, coniferous-small-leaved and pine-larch forests.The main condition is the predominance of mosses and herbs in the lower plant layer. The thickness of the forest floor does not exceed 7 centimeters. Below it is a transit organomineral level.

Economic use

Podzolic soils are of limited use in agriculture. In order to grow the main cultivated plants in this zone, it is required to carry out liming and apply fertilizers - organic and mineral. Equally important is the regulation of the water regime and the creation of an arable layer of considerable thickness.

All these activities lead to significant changes in soil regimes and correction of morphological features. As a result of these processes, it is possible to obtain cultivated podzolic soils. It is important to bear in mind that low temperatures are typical for areas with podzolic lands. That is why it is so important to choose not too whimsical plants.

In its original form, these soils provide people with a lot of industrial wood. The taiga is also a source of berries, nuts, mushrooms and many medicinal plants. In terms of cultivated plants, the following can be grown in the southern regions of this zone:

• cereals;
• potato;
• linen;
• forage plants.

What grows on it?

The main feature of such soils is the location. They are in the taiga. In winter, severe frosts are observed here. Summer is also quite cool. At the same time, the lands are not distinguished by high fertility. However, quite a few boreal forests are considered nature reserves.

The main vegetation in this area is spruce. This tree is very unpretentious and goes well with other conifers or deciduous plants. The second most common is pine. The third position is occupied by fir. To the east of the Urals, Siberian cedars are often found. Podzolic taiga soils are also suitable for larch.

Birch is the most common of deciduous trees. In some places, it reaches the very Arctic Circle. Slightly less common are poplars and aspens. Also in this area you can see linden, mountain ash, juniper. Of course, in terms of fertility, these types of soils are significantly inferior to chernozems and gray forest soils.

Special mention should be made of coniferous-deciduous forests that grow on podzol.In them, the main share is occupied by heat-loving and deciduous coniferous plants. In the southern part of Primorsky Krai, there are many cedars and black firs. Japanese elms and Manchurian ash trees grow in the river valleys. Forest peonies and lilies look very attractive. Also, the area is decorated with many ferns.

Podzolic soils are located in the zone of taiga forests and are not very fertile. Therefore, they are rarely used for agricultural purposes. If it is necessary to grow cultivated plants in this area, it is important to take measures to increase the nutritional properties of the soil.

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