Peat: chemical analysis and basics of complex processing: Textbook. The chemical composition of the ash part of peat

Many gardeners and gardeners have plots located on peat soils Oh. It is customary to consider these soils fertile, since peat is used as a fertilizer on mineral lands. However, this is far from being the case, since not every type of peat is characterized by high fertility, and sometimes it has sharply negative properties. Very often, gardeners and gardeners mechanically endure practical experience and cultivation knowledge different cultures from mineral soils to peat. This is the cause of numerous errors and punctures. After all, peat is a delicate matter, and "where it is thin, it breaks there."
On peat soils, plants die from spring and autumn frosts, which are much stronger than on mineral lands. Wind erosion can not only blow out the sown seeds from the garden, but also carry away part of the upper peat soil layer outside the site. By their physical and chemical properties peat differs sharply from mineral soils. This must be taken into account when determining the optimal doses and timing of the application of lime, mineral and microfertilizers, determining the composition and sequence of measures for tillage, the norms and timing of irrigation, the timing of harvesting, etc. And, finally, we must remember that under certain conditions, First of all, weather, peat can ignite spontaneously. There are cases when fire devoured a peat deposit and spread at a depth of up to several meters, and cars completely fell into such "traps".
PROPERTIES OF PEAT SOILS
A distinctive feature of modern agriculture on garden and garden plots- an increase in the role of the fertility of the soil used, which makes it possible to obtain a greater return from the soil. The fertile soil contributes to a more efficient use of fertilizers and other agrotechnical measures, and also better resists negative external influences - compaction, erosion, contamination with pesticide residues.
Soil fertility is its ability to produce crops. This complex property of the soil is characterized mainly by the level of metabolism and energy with cultivated plants, atmosphere, subsoil, ground and surface waters, animals and soil microorganisms.
basis soil fertility makes up organic matter. It is formed from the remains of plants, dead microorganisms, soil animals, as well as their metabolic products. In the soil, they undergo complex changes, including the processes of decomposition, humification, and mineralization of organic matter. Organic matter preserves the energy of the sun in a chemically bound form, which contributes to the development of the soil, the formation of its fertility.
The agrotechnical properties of the mineral soil are determined by its solid phase, represented by clay, sand and silt particles. Peat soils, unlike mineral soils, do not have a solid phase. The main part of peat is organic matter. In addition, it contains ash and water. Peat ash consists of "pure ash", formed due to ash substances included in the constitutional part of peat-forming plants.
Peat- a relatively young organic formation, the most ancient layers of which began their formation in the post-glacial period, about 10 thousand years ago. Peat arose as a result of the accumulation of semi-decomposed remains of marsh vegetation and mineralization under conditions of excessive stagnant moisture and lack of oxygen.
There are four types of peat deposits: low-lying, transitional, mixed, high-moor. Each type
deposits are characterized by a certain botanical composition of peat, the degree of decomposition, ash content, moisture capacity, bulk density, physical and chemical properties.
The botanical composition is determined by the percentage in its mass of the remains of individual botanical species of peat-forming plants that have preserved anatomical structure. Determination of the botanical composition in field conditions carried out visually. The botanical composition is one of the main indicators that determine the quality of peat, its agronomic characteristics, suitability for the needs Agriculture: sphagnum peat is suitable for bedding for livestock, for storing fruits; woody and woody-sedge are more suitable for fertilizer.
The degree of decomposition of peat is the percentage of the decomposed part of peat (that has lost its cellular structure) to the entire mass of peat. Under field conditions, the degree of decomposition of peat is determined by eye, approximately: less than 20% - slightly decomposed, 20-45% - moderately decomposed, more than 45% - strongly decomposed. Slightly decomposed peat has a yellow or light brown color, plant fibers are clearly visible in it, it does not stain hands, does not pass through fingers when squeezing a lump, the squeezed water has a light yellow color. Heavily decomposed peat has a dark brown or black color, only some plant remains, it stains hands, when squeezing a lump it passes through the fingers, the squeezed water has a dark brown color. High-moor peat (18-20%) has the lowest degree of decomposition, and low-lying forest and forest-bog peat has the highest. Slightly decomposed peat is used for chemical processing, storage of fruits, bedding for livestock; highly decomposed peatlands are used for fertilizer, and peatlands with well-decomposed peat, after draining, are used for growing crops.
Ash content- ash content, expressed as a percentage of dry matter. Raised peat soils are characterized by low ash content (1.2-5%). The composition of the ash is dominated by silica, followed by calcium and aluminum. In peat of lowland soils, the content of ash elements ranges from 5-8% in depleted (transitional) soils, to 12-14% in normally ash soils, and up to 30-50% in high-ash ones. The composition of the ash is dominated by calcium, followed by iron. Normally ash (12-14%) soils are depleted in silica, high-ash soils contain a lot of it. The most important components of ash are phosphorus and potassium. Despite the relatively low accumulation of phosphorus (0.06-0.5%), its reserves in soils can reach 2.5-3.0 kg per 1 m² in a meter thickness. In all peat soils (with the exception of floodplain silty soils), the potassium content is very low (0.02-0.2% by weight of dry peat). In accordance with this content of potassium, its reserves are extremely low.
The content of calcium in the peat of raised soils is very low, and in the peat of lowland soils it is on average 2-4%, reaching 30% and more in their carbonate species.
Peat of bog soils is rich in nitrogen. In high-moor peat soils, the nitrogen content ranges from 0.5-2%, while in lowland peat soils it often exceeds 2%. Nitrogen reserves in the meter thickness are high. The smallest amount of nitrogen - 4.2 t/ha - is accumulated in high peat soil, and the maximum - up to 30 t/ha in lowland soils. The bulk of nitrogenous substances in high-moor peat soils is represented by protein compounds. In lowland peat soils, the bulk of nitrogen compounds is concentrated in complex humus compounds.
Organic matter, which makes up the main part of peat, in upland soils is represented mainly by cellulose, hemicelluloses, lignin, and wax resins. The peat of these soils is poorly humified, humic substances make up 10–15% of the total carbon, and fulvic acids predominate in their composition. The peat of lowland soils is well humified and contains up to 40-50% of humic substances, the predominant part of which is represented by humic acids. The reaction of peat in upland bog soils is acidic and strongly acidic, and in lowland soils, from weakly acidic to neutral.
Peat moisture- moisture content as a percentage of the total mass of peat. natural humidity undrained deposit depends on the type of peat and the degree of its decomposition. As the latter increases, the humidity decreases. High-moor slightly decomposed peat has the highest humidity, and low-lying strongly decomposed peat has the lowest.
moisture capacity- the ability of peat to absorb and retain moisture. It depends on the type, type and degree of decomposition of peat. The upland type of peat has a moisture capacity from 600 to 1200-1800% (this means that one part of peat holds up to 18 parts of water), transitional - 350-950%, lowland - 460-870%. The lower the degree of decomposition of peat, the higher its moisture capacity. For bedding, peat is needed, characterized by high moisture capacity, capable of absorbing a large number of moisture.
Peat soils are characterized by high heat capacity and low thermal conductivity. In summer, the temperature in them at a depth of 10-20 cm is on average 7-8 ° C lower than in zonal mineral soils light mechanical composition. The timing of freezing and thawing of peat soils is shifted compared to mineral soils: in winter they freeze later than mineral soils, and thaw later in spring. The daily amplitude of temperature fluctuations on the soil surface, the threat and force of frosts on peat soils is manifested significantly
higher than on mineral soils. This is not only due to the high heat capacity and low thermal conductivity of peat. Low-lying peat soils (suitable for growing crops) are located at lower elevations of the surface, where cold air flows down from dry lands and where its cold masses stagnate. Drainage of peat soils leads to deterioration of their thermal regime. This is due to the removal of excess water, an increase in the air phase of the soil. Since the thermal conductivity of air is 20 times less than that of water, the thermal conductivity of drained soil becomes lower. However, this does not mean at all that drainage should be neglected. The water content in peat in its natural state reaches 95% of its volume, i.e., almost all pores are occupied by water. BUT optimal humidity soil for vegetables and fruit crops is 55-70%, in which the share of air accounts for 30-45%. When the air content in the soil is less; 15-20% gas exchange occurs slowly, and in conditions of lack of oxygen, instead of decomposition and mineralization of organic matter, its fermentation occurs, and the acidity of the soil increases. Therefore, the most important task of drainage is the removal excess water and decrease in the level ground water. If this is not done, then any measures for the development, cultivation of peat soils and the cultivation of agricultural plants on them turn out to be useless. Drainage should provide not only optimal water, air, food and thermal conditions of the soil, but also create favorable conditions for the implementation of the whole range of measures for the development of peat soils. This complex includes cultures engineering works to bring the surface into an arable state (removal of trees and shrubs, elimination of tussocks, turf, primary tillage, etc.), creation of an arable layer, cultivation of the soil. In the natural state, peat soils are characterized by poor water-physical properties, organic matter and nutrients in them are in a conserved state. The potential fertility of such soils is the result of the bog soil-forming process in vivo. As a result of drainage, cultivation and agricultural use, effective fertility is created. It is characterized by a certain energy and biological level, i.e., the ability to produce agricultural crops, and above all vegetables, berries, and fruits.
If work in the garden plots, skill and practice are skillfully combined with knowledge of the characteristics of peat soils, then the abundance and quality of the crops obtained can undoubtedly be guaranteed.
K. Konstantinov, Ph.D. agricultural sciences

Peat - organic soil formed as a result of natural death and incomplete decomposition of marsh plants under conditions high humidity with a lack of oxygen and containing 50% (by mass) or more organic substances. He is the first constituent element genetic series solid fuels(plant, peat, brown coal, coal, anthracite, graphite), formed under the influence of pressure and temperature (Fig. 2.23). Peat formed in reservoirs is underlain by a layer of lacustrine sediments of various thicknesses; peat, formed as a result of swamping due to excessive moisture, lies on a mineral base of various lithological composition. When the process of peat accumulation is interrupted, peat deposits can be covered by other deposits - in these cases, peat is called buried.

Rice. 2.23. Genetic series of solid fuels

Analysis of the organic part of plants revealed the following chemical composition:

48.. .50% carbon, 38...42% oxygen, 6.. .6.5% hydrogen and 0.5...2.3% nitrogen, and in peat-forming plants it is more or less constant. In the process of photosynthesis, complex compounds are formed that are spent on building the body of the plant and nutrition. All these substances are found in plant tissues in different proportions,

A.A. Nitsenko gives the following data: fiber 15 ... 35%, hemicellulose 18 ... 30%, lignin 10 ... 40%, wax, resins, fats up to 10%, insoluble proteins about 5%, minerals (ash) 1 ,5...20% .

Cell membranes of peat-forming plants consist of cellulose, or cellulose-carbohydrate, and hemicellulose close to it. With age, the cell wall becomes impregnated with lignin, which causes the process of lignification. In the cytoplasm of cells there are various inclusions: starch grains, droplets essential oils and resins dissolved in them. The cytoplasm is alkaline. The contents of the vacuoles contain organic acids, which determines its acidic reaction, as well as tannins. In addition, plants contain waxes (stems and leaves of podbel, reed, cranberries), as well as pentosans (nitrogen-containing non-protein substances).

The influence of these substances on the mechanical properties of peat is ambiguous. Cellulose(a polymer consisting of a chain of glucose molecules) provides sufficient tensile strength, bond energyHemicellulose differs in smaller weight and the best solubility in alkaline solutions, rather short macromolecular chains. When plants decompose and in the presence of moisture, hemicellulose molecules form associates on the surfaces of cellulose microfibrils and contribute to the strengthening of bonds between cellulose chains. Lignin - a polymer with branched macromolecules linked by hydrogen bonds holds together cellulose fibrils and, together with hemicellulose, determines the strength of plant trunks and stems. This nitrogen-free substance belongs to compounds of the aromatic series; richer in carbon and poorer in oxygen than fiber.

The chemical composition of the organic part of peat is not the same for different groups. When moving from the moss group to the grassy and further to the woody group (Table 2.17), the cellulose content increases, which has a significant effect on the strength and deformation properties of peat soils. in sphagnum moss contains a small amount of bitumen, a lot of easily hydrolyzable and water-soluble compounds of the carbohydrate complex. Mosses have chemical immunity, which allows them to persist for thousands of years. The chemical composition of different types of mosses is very different from each other. Herbal peat formers, compared to mosses and shrubs, contain more cellulose. This causes their lability during humification and leads to the formation of peats with a higher degree of decomposition. Woody peat-forming plants differ from mosses and grasses by a high content of cellulose (more than 50%) and true lignin (non-hydrolyzed residue). The content of bitumen in the wood of conifers and some shrubs reaches 15%, and in hardwoods it is ten times less.

Unlike plants, peat contains a very important group of humic substances, consisting mainly of humic and fulvic acids. Humic acids - infusible dark-colored substances that are part of the organic mass of peat (up to 60%), brown coal (20 ... 40%), soil (up to 10%); their structure has not been definitively established. Ion-exchange, water, thermophysical and strength properties depend on HA. HAs are soluble in alkaline solutions and are widely used as plant growth stimulators, components of drilling compositions, organo-mineral fertilizers, etc. Fulvic acids humic substances soluble in water, acids and alkalis, characterized by a reduced carbon content (up to 40% by weight) and, accordingly, a higher oxygen content. They are more oxidized than other humic substances and impart a brown color to peat waters.

Table 2.17

The chemical composition of the substances of peat-forming plants

Peat-forming plants	Chemical composition of peat (in % of organic mass)
	Cellulose	Hemicellulose
sphagnum mosses
sheikh cerium
Cane
heather shrubs
Deciduous wood and on
Softwood

The density of solid particles of peat varies from 1.20 to 1.89 g/cm 3 , for normal ash - up to 1.84 g/cm , for peaty soils - up to 2.08 g/cm 3 , the natural density of watered peat differs little and is 1 , 0 ... 1.2 g / cm 3, the density of the peat skeleton is 0.04 G..0.230 g / cm 3. The values ​​\u200b\u200bof the porosity coefficient of peat vary from 6.6 to 37.5 units and more.

When conducting engineering-geological surveys for the classification of peat by variety, it is necessary to establish degree of decomposition of organic matter /),*/, content 1, and ash content D as(Table 2.18). In addition to the mandatory characteristics, the botanical composition should also be determined.

Table 2.18

Classification of organic soils

/. Classification of peat according to the degree of decomposition (34]
Variety of peat			Degradation degree % (or d.u.)
slightly decomposed
medium decomposed			20 < Да., <45
badly decomposed
2. Classification of peat according to the degree of ash content
Variety of peat			Ash level Dai, units (or %)
normal ash
high ash
3. Classification of peat by botanical composition, type of nutrition and watering of the peat mass
				Variety
Horse		woody		It is distinguished by the type of residues of the main peat formers
	Forest marsh
Lowland		woody
	Forest marsh	woody-moss, woody-herbal
		Herbal, moss, grass-moss
Transition		woody
	Forest marsh	woody-moss, woody-herbal
		Herbal, moss, grass-moss

Peat ash content Das, units, - a characteristic expressed by the ratio of the mass of the mineral part of the soil remaining after calcination to the mass of dry peat. In table. 2.19 shows the values ​​​​of the constitutional ash content (not introduced from the outside) of peat-forming plants. Plant ash consists of the following main elements: silicon, calcium, iron, phosphorus, potassium, magnesium, trace elements (manganese, copper, nickel, etc.) are fixed in the ash in very small quantities. In the plant organs of lowland bogs, the proportion of the mineral part is significantly higher than in the plant organs of raised bogs, with the exception of birch (Table 2.19). The ratios of the organic and mineral parts of marsh plants are different not only for species or groups, but also for different organs of the same plant - the share of the mineral part in the leaves is greater than in the roots and stems.

Determination of the ash content of peat . For determining D as a sample (1...2 g of dry peat) is burned in a muffle furnace, and the residue is calcined at a temperature of 800 ± 25 ° C to a constant weight (with an allowable difference, followed by a weight of up to 0.006 g). When determining the ash content, the difference between two parallel determinations should not be more than 2%.

When using a sample of dry soil, the moisture content is determined in parallel with the burning of peat and then the mass of the wet sample is recalculated for dry. According to the degree of ash content, peat is divided according to Table. 2.18.

Table 2.19

plant type
		organic matter. %
	Alder (Alnus glulinosa)
	Birch (Beiula pubescens)
	Cane (Phragmites communis)
lowland peat	Sedge rough fruit (Carex iasiocarpa)
	Sedge peculiar (C. appropinquate)
	Cotton grass multi-spike (Eriophorum polystachyon)
	Watch (Menyanthes irifoliata)
	horsetail (Eq nisei um heleocharis)
	Drepanocladus vernicosus
	Sphagnum ohtusum
	Pine (Pinus silvestris)
horse peat	Podbel (Andromeda polifolia)
	marsh myrtle (Chamaedaphe calyculata)
	wild rosemary (ledum palustre)
	Cotton grass vaginal (Eriophorum vaginatum)
	sheikh cerium (Scheuchzeria palustris)
	Sphagnum mageHanicum (Sph. medium)
	Sph.fuscum
	sp. angustifoimm

The content of the mineral component is calculated based on the assumption that the organic mass is completely burnt out during ignition and that the mass is lost only due to the burning of organic matter. Loss on ignition generally refers to the organic matter content of soil containing little or no clay and carbonates. For soils with higher percentages of clay and/or carbonates, most of the loss on ignition may be due to factors unrelated to the organic matter content.

The firing temperature specified in is 800 ± 25 °C, but temperatures up to 440 are recommended in other standards. ± 25 °C. Care must be taken when setting the firing temperature., taking into account the following:

• some clay minerals may begin to decompose at temperatures around 550°C;
• chemically bound water may disappear at lower test temperatures; for example, in some clay minerals, this process can begin at 200 °C, and gypsum decomposes at temperatures from about 65 °C;
• sulfides can be oxidized, and carbonates can decompose at temperatures from 650 °C to 900 °C.

For most applications, an ignition temperature of 500°C or 520°C should be used. Drying and calcination times must be sufficient to ensure equilibrium. If the calcination period is less than 3 hours, the report should indicate that the constancy of mass has been confirmed by repeated weighings.

The degree of decomposition of peat Djp, units, - a characteristic expressed by the ratio of the mass of the structureless (completely decomposed) part, including humic acids and small particles of non-humic plant residues, to the total mass of peat. According to the degree of decomposition DDP peat is subdivided according to the table. 2.18.

Determination of the degree of decomposition of peat . The following physical methods are used in field and laboratory conditions: microscopic, weight, eye-macroscopic and centrifugation, as well as determining the degree of decomposition of peat by its botanical composition (calculation method).

Microscopic method . 50 ... 100 cm * of peat are taken from the sample for analysis, mixed, leveled on a plastic or polyethylene sheet with a layer of 3 ... 5 mm. From the prepared layer with a sampler or a spoon, a portion of peat with a volume of 0.5 cm 3 is collected at 10-12 points, evenly spaced over the area, and placed on a glass slide. In the presence of carbonates in peat, for their destruction, a hydrochloric acid solution with a mass fraction of 10% is dropped onto the selected portion with a pipette. If the peat boils, then process the entire portion placed on a glass slide.

When preparing a peat sample with a moisture content of less than 65% (moisture is the ratio of the mass of water in the soil to the total mass of the soil), a part of the sample is placed in a porcelain bowl (the amount of peat is taken on the basis that, after swelling, the peat will fill the cup by 2 / 3 / d of it volume) and pour a solution of sodium or potassium hydroxide with a mass fraction of 5%. After 24 hours, the peat is thoroughly mixed, the lumps are kneaded, and if it remains lumpy, more of the indicated solution is added and mixed until a homogeneous mushy mass is obtained. With drier peat and to speed up sample preparation, it is crushed in a mortar. About 5 cm * of peat is placed in a porcelain bowl and poured with a solution of sodium or potassium hydroxide with a mass fraction of 5%. The bowl with peat is placed on an electric stove and heated in a fume hood, stirring with a glass rod until hard lumps soften and a homogeneous mushy mass is obtained, then the bowl with peat is cooled to room temperature.

A portion of peat for analysis is taken with a spoon. From each sample, a preparation is prepared on three glass slides. A portion of peat placed on a glass slide is diluted with water to a state of fluidity, thoroughly mixed with needles and distributed over the glass with a thin layer even in thickness. The drug should be so transparent that the whiteness of the paper placed under it at a distance of 50 ... 100 mm shows through it. The dry zone separating the working area of ​​the preparation from the edge of the glass should be about 10 mm wide. The glass slide with the prepared preparation is placed on the microscope stage. The drug is examined at a magnification of 56-140 ", making sure that the particles do not move along the glass. On each slide, ten fields of view are examined by moving it and the area occupied by the structureless part is determined as a percentage relative to the entire area occupied by the drug. Based on the obtained on each glass slide, the values ​​of the degree of decomposition are determined by the arithmetic mean of thirty readings, rounding the result to 5%.The absolute allowable discrepancy between the results of determinations carried out by different performers for one sample should not exceed 10%.

weight method . A portion of 50 g is divided into two equal parts, one of which is dried! in a thermostat at a temperature of 105 ° C and weighed to the second decimal place, and the second is elutriated with a stream of water on a sieve with a hole diameter of 0.25 mm. Elutriation is continued until clear water flows out of the sieve. Remaining on

sieve, the washed plant particles are dried in a thermostat to dryness at 105 °C and weighed. The degree of decomposition is determined by the formula

where a- mass of dry fiber from elutriated sample; b- the same, from an unwashed sample. The conversion of the degree of decomposition determined by the weight method to the degree of decomposition by the microscopic method should be carried out using the graph (Fig. 2.24) in order to classify the soil by variety (Table 2.18.)

Rice. 2.24. Graph for converting the degree of decomposition determined by the gravimetric method to the degree of decomposition by the microscopic method

Eye-macroscopic method. Using table. 2.20, the structural and mechanical properties of peat are evaluated by eye when it is squeezed in the hand and by the color of the water squeezed out of it. The complex of signs of visual determination is supplemented with another indicator - a smear of peat. To do this, an average sample of 0.5 ... 1.0 cm 3 in volume is taken from several places of a peat sample taken from a deposit and placed on a piece of thick paper or on a field diary page. By pressing the index finger on the sample, a horizontal smear of 5 ... 10 cm is made to assess the degree of decomposition.

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ASH CONTENT- mass of solid inorg. residue (ash) formed after the complete combustion of a fuel sample in wa (coal, peat, etc.) under certain conditions. It is usually expressed in% of the mass of the analyzed sample and is designated A. 3. allows you to judge qualitatively ... ... Chemical Encyclopedia

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• Peat deposits of the Republic of Belarus, suitable for integrated development in the near and long term, Absent. Data on the use of peat resources of the Republic of Belarus over the past years are given and new tasks are set, caused by modern realities. Analyzed the criteria and methodology ...

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Physical and chemical characteristics

Peat - organic fertilizer, is a plant mass decomposed in conditions of excessive moisture and lack of air. The composition of peat includes non-humified plant residues, humus, and mineral compounds.

Peat classification

According to the conditions of formation, peat is divided into three types:

Agrochemical assessment of peat is carried out according to the following properties:

Botanical composition

determines acidity, ash content, degree of humification, supply of nutrients.

The degree of decomposition of peat

. There are weakly decomposed (5-25% humified substances) and moderately decomposed peat (25-40%).

Ash content of peat

can be normal (up to 12% ash by dry weight) and high (more than 12%). High-ash, as a rule, are low-lying peats with an ash content of 20-30% or more. Increased ash content due to the content of calcium in the form of lime and phosphorus (vivianite) increases the value of peat. decreases during the transition from low-lying peat to high-moor peat.

• . Most of all, peat contains this element. Its main part is in organic form and becomes available to plants only after mineralization.
• . The content in peat is low. At the same time, two-thirds of it is soluble in weak acids and available to plants.
• . The content is very low, only less than half of it is in a state available to plants.
• . Of all the trace elements, peat contains the smallest amount.

Acidity of peat (

pH) is a very important indicator. The method of using peat depends on the level of acidity. With a pH of 5.5 or less, peat (even lowland) is not allowed to be used without prior composting with lime, phosphate rock, ash, manure, etc. Taking into account hydrolytic acidity, all types of peat are capable of being composted into digestible forms for plants.

Absorption capacity, absorption capacity (CEC)

- an indicator that is significant when using peat as bedding material in animal husbandry as a material that absorbs moisture (moisture capacity) and gases, usually ammonia.

Maximum moisture capacity is a hallmark of high-moor peats. The indicator gradually decreases with the transition to lowland types, but remains quite high.

Agrochemical indicators, % on absolutely dry mass of various types of peat, according to:
Peat type	ash	pH values		organic matter
									mg eq/100g dry weight
lowland
transition
riding

Application

Agriculture

Peat is widely used in agriculture. In animal husbandry, various types of peat are used for animal bedding. In crop production, peat is used as a component of various composts, in the preparation of peat pots and cubes, as a substrate for greenhouses, as a mulching material, as an independent fertilizer.

Fertilizer brands registered and approved for use in Russia, in the production of which peat is used, are placed in the table on the right.

Application methods

Peat as a fertilizer is applied on light soils in or.

As a mulching material, surface-ventilated lowland and transitional peat mosses are used.

The drained peatlands are used for crop cultivation. For these purposes, peat extraction is suitable after removing the upper layer of the peat bog with a thickness of the remaining peat layer of at least 50 cm. In this case, liming, the use of various and.

Industry

Peat is a combustible mineral, the predecessor of a number of coals, used as a fuel. (a photo)

Deep chemical processing of peat raw materials makes it possible to obtain humic acids, bitumen, methyl and ethyl alcohol, acetic and oxalic acids, furfural, dry ice, fodder yeast, peat coke, semi-coke, and so on.

Behavior in soil

The introduction of pure peat into the soil is recognized as ineffective. Raw peat contains 80-90% water, and with one ton of it only 100-200 kg of dry matter is added.

Dry peat has a high absorption capacity, and its application leads to the absorption of moisture from the soil. Peat, even at a moisture content of 35-40%, causes the soil to dry out, which, in turn, leads to a slowdown in the decomposition of peat itself, since it does not decompose well in a dry arable layer.

Application on various types of soil

To increase the availability of nitrogen and other nutrients, peat is composted with biologically active components (slurry, feces). For composting, peat is used with a degree of decomposition of more than 20%; lime and ash are added to improve the nutritional qualities of the compost. (a photo)

Peat is used for the preparation of peat-ammonia fertilizers (TMAU) and various peat substrates for greenhouse vegetable growing.

Light soils

. It is allowed to use low-lying peat rich in lime (peat tuffs) or phosphorus (vivianite peat) as a fertilizer. Peat must meet the following agrochemical characteristics: pH - more than 5.5, ash content - more than 10% (including CaO content more than 4%), degree of decomposition - more than 40-50%. The efficiency of peat application increases with the simultaneous application of small doses of other organic fertilizers (slurry, semi-liquid manure, feces, bird droppings).

Impact on crops

Peat fertilizers and composts have a positive effect on all crops, increasing the quantitative and qualitative characteristics of productivity.

Receipt

Peat from natural deposits is obtained in various ways. The most modern - milling. The peat deposit is drained using a system of diversion channels, then it is cleared of tree and shrub vegetation and leveled. All peat extraction operations are performed by one specialized combine, the design of which provides for the strengthening of the suction nozzle on the front, and steel cutters on the back.

The cutters destroy the layers of peat, through the nozzles the loosened peat is sucked into the combine and transported to the body with the air flow. Along the way, the peat crumb dries up. From the body on the belt conveyor, it is stored along the edge of the field and subsequently delivered to peat processing plants. (a photo)