Peaty marshy soils story to school. Peat soils, their improvement. Characteristics of peat-bog soils

swamp soils most common in the tundra and taiga-forest zones. They are also found in the forest-steppe and other zones. The total area of marsh soils in the taiga-forest and tundra zones is about 100 million hectares.

Bog soils are formed as a result of swamping of land or peat in water bodies. The bog soil formation process is characterized by peat formation and gleying of the mineral part of the soil profile. It develops only under the condition of excessive moisture.

Peat formation occurs with the accumulation of undecomposed or semi-decomposed plant residues as a result of poorly expressed processes of humification and mineralization of vegetation. The consequence of peat formation is the conservation of ash nutrition elements. It lies in the fact that the nutrients absorbed by plants, due to the weak mineralization of plant residues, do not pass into forms accessible to other generations of plants.

Gleying is a biochemical process of converting oxide iron into ferrous iron and occurs under the action of anaerobic microorganisms, which split off part of the oxygen from the oxide forms of the compounds.

There are three types of mineral nutrition of swamps- atmospheric, atmospheric-soil and alluvial-deluvial. Depending on the type of nutrition and the conditions of formation, upland, lowland and transitional bogs are formed, which differ both in the composition of vegetation and soils.

Raised bogs are formed from transitional swamps or from direct swamping of land by atmospheric or soft groundwater. Raised bogs are usually located on flat, poorly drained relief elements with poor soils. The content of raised bogs dissolved in water nutrients very little, therefore, under such conditions, vegetation that is extremely undemanding to nutrients develops.

lowland swamps are formed in low relief elements, when the land is swamped by hard groundwater or when water bodies are peaty. There is a sufficient amount of nutrients in such waters, therefore cereals, sedges, green mosses develop well in lowland bogs, black alder, birch, willow, etc. and others.

In the process of development, lowland marshes turn into other types of marshes. This happens because the upper part of peat, when growing, gradually breaks away from hard groundwater and plant nutrition begins to be carried out due to soft atmospheric precipitation. In this regard, the composition of vegetation changes and the lowland swamp turns into a transitional one.

transitional swamps are formed from lowlands or are formed directly during the swamping of land, when moistening is carried out alternately by hard and soft waters. According to the composition of vegetation, transitional bogs occupy an intermediate position between upland and lowland ones, approaching more to upland ones. Transitional swamps, in turn, with further development, break away from groundwater even more and turn into raised ones.

The transformation of water bodies into swamps occurs in stages. At the beginning of swamping, silt is deposited at the bottom of the reservoir, which is brought from the surrounding hills by melted snow water and atmospheric precipitation. This silt is mixed with silt that enters the water when the banks are washed away. As a result of these long-term deposits, the reservoir gradually becomes shallower.

At the second stage, the reservoir is populated by planktonic (suspended in water) organisms, mainly algae and crustaceans. After dying, they mix with silt at the bottom of water bodies, increase the total mass of sediments and further contribute to their shallowing.

Simultaneously with the second, the third stage also occurs - the shores and coastal belts of reservoirs are overgrown with vegetation that attaches to coastal and bottom sediments. After dying, the plants sink to the bottom, decompose under anaerobic conditions and form peat.

In connection with the deposition of peat, a gradual shallowing of the reservoir occurs, the vegetation moves farther and farther from the coast to the middle, which eventually leads to its complete overgrowth and peat formation. Finally, the last, fourth, stage comes, when the reservoir turns into a grassy or sedge swamp.

Peating occurs the faster, the shallower the reservoir and the calmer the water in it.. The process of formation of swamps is widespread in the zone of glacial deposits, where there are many small lakes, streams and rivers with slowly flowing water.

Soils of lowland swamps have a neutral or slightly acidic reaction, contain a large amount of nitrogen, high-ash, with low moisture capacity. The soils of raised bogs, on the contrary, are acidic, contain much less nitrogen, low-ash, but very moisture-intensive. Soils of transitional swamps have intermediate properties.

Lowland peat has the best physical and chemical properties: it has a high degree of decomposition, its ash content reaches 25% or more, the nitrogen content is 3-4%, the reaction is slightly acidic. The content of phosphorus is relatively low and varies widely - from 0.15 to 0.45%. All peat soils are poor in potassium.

Raised bog peat characterized by a lower degree of decomposition, its ash content does not exceed 5%, it is poor in nutrients, the reaction is strongly acidic.

Peat of all types of bogs has a high absorption capacity, but the degree of saturation with bases in lowland peats reaches 70-100%, and in high-moor peats it does not exceed 15-20%. Peat is characterized by a very high moisture capacity, but it is especially high in riding peat - 600-1200%. With increasing decomposition, the moisture capacity of peat decreases.

Bog soils are classified according to two criteria.: by belonging to a particular type of swamp, and within the same type - by the thickness of the peat horizon. According to the first feature, bog upland and bog lowland soils are distinguished, and according to the second, peat-gley and peat soils are distinguished. In addition, in the type of raised bog soils, a genus of transitional bog soils is distinguished, which are similar in properties to raised and lowland bog soils.

Peat and bog soils are widely used in agriculture: peat - as a source of organic fertilizers, and swamp soils after cultivation - as agricultural land. IN pure form low-lying peat, well decomposed, is used as a direct fertilizer. Moss peat from raised bogs is used for bedding in cattle yards. Subsequent composting with lime, phosphate rock and other mineral fertilizers improves its quality as a fertilizer.

The most valuable for the development of the soil of lowland swamps. After drainage and carrying out cultural and technical and agrotechnical measures, they become highly productive agricultural lands, which are used for arable land, hayfields, and pastures.

Peat soils, their improvement

There is an opinion among the people that such soils seem unsuitable for growing vegetables and berry bushes, but after two or three years of their development, most horticultural crops can already be grown on them.

But the approach to the development of each type of peat bog should be individual.- depending on what type of swamp there used to be in this place.

Peaty soils are very diverse in their physical properties. They have a loose permeable structure that does not require special improvement. But they all contain little phosphorus, magnesium and especially potassium, they lack many trace elements, primarily copper.

Depending on their origin and the thickness of the peat layer that forms them, peaty soils are divided into lowland, transitional, and upland.

Most suitable for growing horticultural and garden plants low-lying peatlands, often located in wide hollows with a slight slope. These soils have good vegetation cover. Peat on such peatlands is well decomposed, so it is almost black or dark brown, lumpy. The acidity of the peat layer in such areas is weak or even close to neutral.

Lowland peatlands have a fairly high supply of nutrients compared to transitional and especially upland peatlands. They contain a lot of nitrogen and humus, since the plant remains are well decomposed, the acidity of the soil is weaker, they have enough water that must be diverted into ditches.

But, unfortunately, this nitrogen is found in low-lying peatlands in a form that is almost inaccessible to plants, and only after ventilation can it become available to plants. Only 2-3% of the total amount of nitrogen is in the form of nitrate and ammonia compounds available to plants.

It is possible to accelerate the transition of nitrogen to a state available to plants by draining peat soil and enhancing the activity of microorganisms that contribute to the decomposition of organic matter by introducing a small amount of manure, ripe compost or humus into the soil.

Raised peatlands are usually excessively moistened, since they have a rather limited runoff of rain and melt water. They are highly fibrous, since they do not have conditions for a more significant decomposition of plant residues. This leads to a strong acidification of peat, which explains its very high acidity. Such peatlands have a light brown color.

Nutrients in high-moor peat, which are scarce in any peat soil, are in a state inaccessible to plants. And soil microorganisms that help maintain soil fertility are often simply absent in them.

When laying gardens and orchards on such soils, their cultivation requires high costs. In order for such soils to become suitable for growing horticultural plants, lime, river sand, clay, rotted manure, and mineral fertilizers must be added to them.

Lime will reduce acidity, sand will improve the structure, clay will increase viscosity and add nutrients, and mineral fertilizers will enrich the soil. additional elements nutrition. As a result, the decomposition of plant residues of peat will accelerate and conditions will be created for growing cultivated plants.

And in its pure form, high-moor peat can practically only be used as bedding for livestock, since it absorbs slurry well.

For all types peaty soils characterized by low thermal conductivity, so they slowly thaw and warm up in the spring, much more often exposed to return frosts, which delays the start of spring work.

It is believed that the temperature of such soils is on average 2-3 degrees lower during the growing season compared to the temperature of mineral soils. On peat soils, frosts end later in spring and begin earlier in autumn. create a more favorable temperature regime on such soils there is only one way- by draining excess water and creating loose structural soil.

Peat soils in their natural state are almost unsuitable for growing horticultural and horticultural plants. But due to the presence of a large amount of organic matter in them, they have a significant "hidden" fertility potential, all four "keys" of which are in your hands.

These keys are lowering the groundwater level, liming the soil, applying mineral additives and using organic fertilizers. And now let's try to get acquainted with these "keys" in a little more detail.

GROUNDWATER LEVEL DECLINE

To remove excess moisture in the area and improve the air regime, peat soils often have to be drained, especially in new areas. Of course, it is easier to do this all at once in the entire garden, but much more often you have to do this only on your site, trying to create your own local simplest drainage system.

The safest way to arrange simple drainage it is possible, laying in the grooves with a width and depth of two bayonets of a shovel drainage pipes, pour sand over them, and then soil.

Much more often, instead of pipes, branches, cut stalks of raspberries, sunflowers, etc. are placed in drainage ditches. They are covered first with rubble, then sand, and then earth. Some craftsmen for this purpose use plastic bottles. To do this, they cut off the bottom, screw the cork, make holes on the side with a hot nail, insert them into each other and lay them instead of the drainage pipe.

And if you are very unlucky and you have a site where the groundwater level is very high and it is rather difficult to lower it, then there will be even more worries.

In order to prevent further contact of tree roots with these same groundwater, you will have to solve not one, but two “strategic” tasks at once- reduce the level of groundwater on the site as a whole and at the same time raise the level of the soil at the site of planting trees by creating artificial mounds from imported soil. As the trees grow, the diameter of these mounds will need to be increased annually.

SOIL DEOXIDATION

Peat soils come in different acidity- from weakly acidic and even close to neutral (in peat bog lowland soils) to strongly acidic (in peat bog highland soils).

Under deoxidation acidic soil understand the introduction of lime or other alkaline materials into it to reduce its acidity. In doing so, the most common chemical reaction neutralization. Most often, lime is used for these purposes.

But, in addition to this, liming peat soils also enhances the activity of various microorganisms that assimilate nitrogen or decompose plant residues contained in peat. In this case, brown fibrous peat turns into an almost black earthy mass.

At the same time, hard-to-reach forms of nutrients contained in peat turn into compounds that are easily digestible by plants. And phosphorus and potash fertilizers introduced into the soil are fixed in upper layers soil, are not washed out of it by groundwater, remaining long time available to plants.

Knowing the acidity of the soil in your area, alkaline materials are introduced in the fall. The dose of their application depends on the level of soil acidity and for acidic peat soils, on average, about 60 kg of ground limestone per 100 square meters. meters of area, for medium acid peat soils- on average about 30 kg, on slightly acidic- about 10 kg. On peat soils, in acidity close to neutral, limestone can not be applied at all.

But all these average doses of lime application vary greatly depending on the value of acidity, especially on acidic peatlands. Therefore, before adding lime, its specific amount must be clarified once again depending on the exact value of the acidity of the peat bog.

A wide variety of alkaline materials are used for liming peat soils: ground limestone, slaked lime, dolomite flour, chalk, marl, cement dust, wood and peat ash, etc.

INTRODUCTION OF MINERAL ADDITIVES

An important element in improving the physical properties of peaty soils is their enrichment with minerals.- sand and clay- which increase the thermal conductivity of the soil, accelerate its thawing and increase warming. At the same time, if they have an acidic reaction, you will have to add an additional dose of lime to neutralize their acidity.

At the same time, clay must be applied only in dry powder form, so that it mixes better with peat soil. The introduction of clay into peat soil in the form of large lumps gives an insignificant result.

The lower the degree of decomposition of peat, the greater the need for mineral additives. On heavily decomposed peatlands, 2-3 buckets of sand and 1.5 buckets of dry powdered clay per 1 sq. meter, and on weakly decomposed peat bogs, these doses should be increased by a quarter.

It is clear that such an amount of sand cannot be introduced in one or two years. Therefore, sanding is carried out gradually, from year to year (in autumn or spring), until they improve physical properties soil. You will notice this yourself in the plants grown. The sand scattered over the surface is dug up with a shovel to a depth of 12-18 cm.

INTRODUCTION OF ORGANIC AND MINERAL FERTILIZERS

Manure, peat-dung or peat-fecal composts, bird droppings, humus and other biologically active organic fertilizers are applied in an amount of up to 0.5-1 bucket per 1 sq. meter for shallow digging to quickly activate microbiological processes in peat soil, contributing to the decomposition of organic matter in it.

To create conditions favorable for plant growth, mineral fertilizers must also be applied to peat soils: for the main tillage - 1 tbsp. spoon of double granular superphosphate and 2.5 tbsp. spoons of potash fertilizers per 1 sq. square meter, and in the spring additionally- 1 teaspoon of urea.

Most peat soils have a low content of copper, and it is in a form that is difficult for plants to access. Therefore, the introduction of fertilizers containing copper into peat soil, especially on acidic peat soils, has a significant effect. Most often used for this purpose blue vitriol at the rate of 2-2.5 g / m2, previously dissolving it in water and watering the soil from a watering can.

Good results are obtained by the introduction of boron microfertilizers. Most often, 2-3 g are taken for foliar feeding of seedlings or adult plants. boric acid per 10 liters of water (1 liter of this solution is sprayed on plants in an area of 10 sq. M).

Then the peat soil, together with the mineral soil, manure, organic and mineral fertilizers and lime poured on top, must be carefully dug up to a depth of no more than 12-15 cm, and then slightly compacted. This is best done in late summer or early autumn when the soil has dried out significantly.

If it is not possible to cultivate your entire site at once, then master it in parts, but applying all the above amount of mineral additives and organic fertilizers to them at once, or first filling them with loose, fertile soil planting pits, and already in subsequent years, carrying out work on the cultivation of the soil in the aisles. But this is the worst option, because it is better to do all this at once.

On already developed peat soils, there is a gradual decrease in the thickness of the peat layer by about 2 cm per year due to its compaction and mineralization of organic matter. This happens especially quickly in areas where the same vegetables are grown for a long time without observing crop rotation, requiring frequent loosening of the soil.

To prevent this from happening, cultivated peat soil in gardens, and especially in garden plots, needs annual additional application of organic fertilizers.

If this is not done, then every year a gradual irreversible destruction of peat (its mineralization) will occur on your site, and in 15-20 years the soil level on your site may be 20-25 cm lower than it was before the development of the site, and the soil will become waterlogged.

At the same time, the soil on your site will no longer be fertile peat, but infertile sod-podzolic, and its physical properties will greatly change for the worse.

To prevent this from happening, among other things, as mentioned above, a well-thought-out crop rotation system, saturated with perennial herbs, must constantly operate on your site.

In the future, it will be necessary to annually import and apply either a sufficient amount of organic fertilizers (10-15 buckets per 100 square meters), or other soil.

And if there is no manure or compost, then it can help out green manure. Sow and bury lupins, peas, beans, vetch, sweet clover, clover.

V. G. Shafransky

Bog soils are formed in various swamps. They are divided into types: bog high peat and bog lowland peat.

Bog upland peat soils. These soils are formed on raised bogs in the northern and middle taiga in the north of Western Siberia, in Kamchatka, Sakhalin. Indicator plants for such soils are sphagnum mosses, from woody soils - strongly oppressed pine or spruce, dwarf birch, and from semi-shrubs - wild rosemary, Cassandra, cloudberries, blueberries, cranberries, sheikhzeria, cotton grass.

There are subtypes: marsh raised peat-gley (peat thickness less than 50 cm) and marsh raised peat (peat thickness more than 50 cm) soils.

Bog raised peat-gley soils are found in shallow drainless depressions of plain watersheds and along the edges of raised bogs. In their profile, the following horizons are distinguished: A 0 0 - sphagnum tow 10 ... 20 cm thick from undecayed stalks of sphagnum mosses with an admixture of rhizomes of semishrubs, tree roots and grasses; T - peat horizon with a thickness of 20 ... 50 cm, subdivided into subhorizons T (slightly decomposed) and T 2 (with an increased degree of decomposition); color from light brown to dark brown depending on decomposition; the transition is abrupt; G - mineral gley horizon, the upper part of which is bluish-dark gray due to flowing humus, and the lower part looks like a bluish-gray gley on loamy-argillaceous deposits or a rusty-brown ferruginous horizon on sands and sandy loams.

The soils are strongly acidic (pH KCl 2.6...3.8). The degree of saturation with bases is low (10 ... 50%), the ash content is low (2.4 ... 6.5%), the density is low (0.03 ... 0.10 g / cm 3), the moisture capacity is high (700 ...1500%).

Bog raised peat soils (Fig., a) are common in the central parts of raised peat bogs. Profile differentiation into horizons is weakly expressed. From above, sphagnum tow is usually distinguished; under it lies heavily saturated with moisture brown or yellow-brown peat. The boundary between peat soil and peat-organogenic rock is difficult to distinguish. The soil differs from this rock in its high filtration coefficient and high water permeability when the groundwater level drops. The soils are low-ash, strongly acidic (pH K p 2.5...3.6), soil saturation with bases is low (10...30%), absorption capacity is 80...90 mg-eq/100 g. The content of gross forms calcium, potassium, phosphorus is low (0.1 ... 0.7%, 0.03 ... 0.08, 0.03 ... 0.20%, respectively).

The main genera of raised bog soils are: ordinary (organogenic horizon of sphagnum or shrub-cotton peat), transitional (sphagnum wood-moss and infested grass-moss), humus-ferruginous (on sands).

Upland bog soils are divided into species according to the thickness of the organogenic horizon and the degree of decomposition of peat. According to the thickness of the organogenic horizon, the following types are distinguished: peaty-gley thin soils with a peat thickness of 20 ... 30 cm; peat-gley (30...50 cm); peat on small peat (50...100 cm); peaty on medium peat (100...200 cm); peaty on deep peats (> 200 cm). According to the degree of decomposition of peat in the upper stratum (30 ... 50 cm), peat (< 25 %) и перегнойно-торфяные (25...45 %) почвы.

Bog lowland peat soils. These soils (Fig. 6) develop in deep relief depressions in watershed areas, depressions in river terraces, and on slopes in the taiga-forest and forest-steppe zones with excessive moisture from mineralized groundwater.

Rice. Bog soils: a - marsh high peat; b- marsh lowland peat

Subtypes of peat bog lowland soils: bog lowland depleted peat-gley, bog lowland (typical) peat-gley, bog lowland depleted peat, bog lowland (typical) peat.

Bog lowland peat-gley soils are common under nutrient-demanding (eutrophic) herbaceous hygrophyte tree-shrub vegetation and hypnum mosses in depressions on watersheds and river terraces, along the outskirts of lowland bogs. The following horizons are distinguished in the profile: peat-humus (T p) with a thickness of 30 ... 80 cm, dark brown in color, intertwined with plant roots; humus (A 1) - black, bluish-dark gray in color, saturated with water; gley (G) - gray, olive-gray color. Rusty spots, iron hydroxide smears and black manganese formations are observed along the roots of plants. Degree of saturation with bases 20...30%

Bog lowland peat soils are found in the central part of lowland bogs. Their profile develops within peat layers with a thickness of 30...60 cm (in heavily watered bogs) to 60...70 cm (in slightly watered bogs). The peat horizon T is subdivided into subhorizons (T 1 , T 2 , etc.) according to the degree of peat decomposition. Soils differ from peat-organogenic rock in color and degree of decomposition. The rock is usually light yellow, yellow-brown, from well-preserved plant remains. Ash content ranges from 10 to 30...50%.

Main genera: common, carbonate (contain from 5...10 to 20...30% calcium carbonates), solonchak (0.3...2.0% soluble salts), mineralized (5...25% Fe 2 0 3 and more), silty (the upper part is enriched with silty-silty particles).

Soil subgenera: moss, woody, herbaceous. The types of these soils are similar to those of raised bog soils.

Bog lowland peat soils have a slightly acidic or neutral reaction (pH KCl 5.0 ... 6.5). The absorption capacity is 130...150 mg equiv/100 g of soil, the degree of saturation with bases is 90...97%. Soils contain 1.5 ... 5% calcium, 1.6 ... 3.8% nitrogen, are poor in potassium (0.08 ... 0.20%) and phosphorus (0.45 ... 0.60 %).