The production of nitrogen fertilizers is one of the leading sectors of agriculture and chemical industry Russia. This is due not only to the demand for top dressing of this type, but also to the relative cheapness of the process. In addition, nitrogen is a priority macronutrient that ensures the normal growth and development of a plant organism, that is, the introduction of nitrogen fertilizers (as well as their production) can be considered a primary farming task.

The role of nitrogen in plant life

Nitrogen is considered one of the most important elements of the plant cell. As part of nucleic acids, nitrogen is partially responsible for the transmission of hereditary information, thereby performing a reproductive function. Also, nitrogen is a part of chlorophyll, taking a direct part in the metabolic process.

In the case of a nitrogen deficiency, the following symptoms can be observed:

• slowdown in growth - up to a complete stop;
• pallor of leaves;
• the appearance of light spots;
• yellowing of the leaves;
• small fruits and shedding of fruits.

Acute nitrogen starvation can lead to:

1. intolerance to low temperatures in winter and, as a result, lack of harvest in subsequent seasons;
2. suppression of the immune system of plants;
3. death of the most weakened shoots and culture as a whole. That is why you should not delay the introduction of top dressing in case of signs of insufficient nitrogen content in the soil.

Nitrogen fertilizers most commonly used in agriculture

- characterized by a high nitrogen content (up to 36%), can be used not only for the main application, but also as a one-time dressing, effective on slightly moist soils and practically useless on sandy soils, requires unconditional adherence to storage rules.

Ammonium sulfate - fertilizer with an average nitrogen content (up to 20%), ideal for the main application, since it is well fixed in the soil, storage conditions are not demanding.

Urea (urea) - nitrogen content reaches 48%, provides high-quality results in combination with organic fertilizers, suitable for foliar feeding.

- alkaline fertilizer, well suited for non-chernozem soil.

Organic nitrogen fertilizers (manure, bird droppings, peat, compost) are used very actively, however, a low percentage of nitrogen content and the need for a large amount of time for its mineralization significantly reduce the effectiveness of these fertilizers. The advantage is the low cost.

Nitrogen fertilizer production technology

The production of nitrogen fertilizers is based on the feedstock, which is ammonia. Until recently, ammonia was obtained from coke (coke oven gas), so many enterprises specializing in the manufacture of fertilizers were located in the immediate vicinity of metallurgical plants. Moreover, large metallurgical plants practice the production of nitrogen fertilizers as a by-product.

To date, the priorities have changed somewhat and the main raw material for fertilizers is more and more not coke oven gas, but natural gas. So modern fertilizer producers are deployed near gas pipelines. Also, the production of nitrogen fertilizers was successfully established on the basis of the use of oil refining waste.

The technology for the production of nitrogen fertilizers in the chemical industry is not considered difficult, however, its nuances are not always clear to the average person. If we simplify the details of the process as much as possible, then everything will look something like this: an air stream is passed through the generator with burning coke, the resulting nitrogen is mixed with hydrogen in a certain proportion (in this case, the values ​​of pressure and temperature are extremely important), which gives the output necessary in production fertilizers ammonia.

Further details of the process are tied to a specific type of fertilizer: the production of ammonium nitrate (ammonium nitrate) is based on the neutralization of nitric acid with ammonia, production involves the interaction of ammonia with carbon dioxide at a certain temperature and pressure, ammonium sulfate is formed by passing ammonia gas through a sulfuric acid solution.

Nitrogen fertilizers in liquid or dry form are used to feed plants. Nitrogen is contained in humus, which contains almost 5%. The growth of plants and the intensity of the harvest depend on the amount of humus in the soil. The amount of this element is not stable and decreases under the influence of various factors. First, nitrogen is carried out with the crop. Secondly, it is washed out by water and groundwater. Thirdly, the depletion of the soil by various garden and field crops. The climate and weather in the region play an important role, therefore, it is necessary to apply nitrogen fertilizers to the soil once a year, increasing the amount of substance in the humus.

The application rates in a particular region are different, since the level of substance content differs in chernozems, podzolic, sandy and sandy loam soils.

Nitrogen deficiency symptoms in plants spread to leaves and stems. Among the main features it is worth noting:

• Leaf color change from green to yellow, or from yellow to orange.
• Plants turn pale green as chlorophyll levels gradually decrease.
• The stems become brittle and short.
• Weak tillering.
• The leaves are small, fall off quickly even before the onset of autumn.
• The ovaries form, but fall off early.
• The seeds and fruits ripen quickly.
• Plants begin to dry out, which is why the lateral root system does not develop well.

Excess nitrogen

By the appearance of plants, you can also determine an excess of nitrogen fertilizers:

• The stems become very thick.
• The leaves become dark green in color.
• Plants begin to bloom and bear fruit late.
• Plants become succulent and soft.
• Increases susceptibility to disease and insect damage.
• Yields are falling.
• Fruits ripen small, with a lot of nitrates.
• After harvesting, fruits and seeds deteriorate quickly.
• Accelerated vegetation.

Routes of nitrogen supply to plants

Organic nitrogen is supplied to bushes, flowers and trees, and garden crops through the mineralization process. The applied nitrogen fertilizers must process microorganisms living in the soil.

Precipitation in the form of rain, hail, snow also brings nitrogen with it. This substance is contained in certain bacteria, microbes, fungi and algae, but the amount of the element coming from the air is not enough for the normal development of plants and crops. Determining the sufficient nitrogen level in them is simple:

• Plants grow very quickly.
• The leaves are deep dark green in color and large in size.
• The yield is normal.
• The shapes of fruits and seeds do not differ from the norm.

All this happens due to the fact that protein is concentrated in the tissues of crops, which contributes to the normal development of plants. Almost all field, garden and horticultural crops are fed with nitrogen. But this type of fertilizer is not applied for legumes.

Fertilizer dosage

Feeding rates differ for horticultural and horticultural crops - it depends on the method of nitrogen fertilization. The standard doses are:

• For vegetables, berry and fruit bushes, flowers, potatoes, 0.6-0.9 kg of fertilizer is used per 100 m2 plot (the main method of application).
• For ordinary, vegetables, potatoes, a lower rate is used - 0.15-0.2 kg / 100 m2, for fruit and berry plants - 0.2-0.3 kg / m2.
• The solution will require 0.015-0.03 kg of nitrogen, which dissolves in 10 liters of water.
• For foliar feeding, you will need to prepare nitrogen solutions of different concentrations - from 0.25% to 5%. 0.025-0.05 kg of fertilizer is applied to 10 liters of water, which is suitable for cultivating land plots from 100 to 200 m2.

The main types of nitrogen fertilizers

They are mineral and organic. The first group includes the following nitrogen substances:

• Ammonia, represented by ammonium chloride.
• Nitrate - sodium and calcium nitrate.
• Amide - urea, calcium cyanamide, methylene-urea, urea-formaldehyde, ammonia, made on the basis of urea.
• Ammonium-nitrate - ammonium and lime-ammonium nitrate, ammonia, which are made on the basis of ammonium and calcium nitrate.
• Ammonium sulfonitrates.

The second group includes organic nitrogen fertilizers, which include:

• Manure.
• Bird droppings.
• Chicken droppings.
• Pigeon droppings.

Such fertilizers can be obtained independently by making compost heaps, which are based on peat or household waste. It is also made with nitrogen from green mass, for example, clover, sweet clover, vetch, lupine, lake silt, green foliage.

Additional types of fertilizers are:

• Nitrogen-phosphorus-potassium substances.
• Liquid nitrogen substances.

The use of nitrogen along with potassium and phosphorus compounds allows for increased flowering and higher yields. Fertilizers must be applied correctly. For example, adding such additives during flowering can degrade and reduce the amount of future crops.

Liquid nitrogen mixtures are quickly absorbed by plants, have a prolonged effect on bushes and trees, and are evenly distributed during fertilization. The main disadvantages are:

• Difficult to store and transport.
• You can burn the leaves.
• Special tools are needed to properly distribute the liquid mixture.

A popular liquid fertilizer is ammonia, which should be embedded deeply into the soil - no less than 8 centimeters. This will prevent it from evaporating. It is also recommended to use liquid ammonia, which dissolves in water. In such a cocktail, the nitrogen concentration will be 20%.

Features of the introduction

Nitrogen fertilizers are applied to the soil at the end of winter or at the beginning of spring, when plants begin to actively grow and develop, receiving the maximum amount of nitrogen. To increase the efficiency from the use of such fertilizer, it is necessary to adhere to the following rules:

• Fertilizers must be stored correctly.
• Be sure to check the expiration date before use.
• The most favorable period for fertilization is the spring-autumn period, when sewage and groundwater will leach less nitrogen from the ground.
• It is necessary to apply to the soil in small doses, fractionally, which will increase the quality of feeding.
• For acidic soils, it is recommended to use nitrogen mixed with lime.
• It is necessary to carry out preventive measures from time to time.
• It is worth alternating urea, liquid nitrogen feeding.

Nitrogen fertilizers- nitrogen-containing substances, which are used to increase the nitrogen content in the soil. Depending on the form of nitrogen compound, one-component nitrogen fertilizers are divided into six groups. They are used in the main method as a pre-sowing fertilizer and as a quality. The production is based on the production of synthetic ammonia from molecular hydrogen and nitrogen.

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Nitrogen fertilizer groups

Depending on the nitrogen compound contained, one-component nitrogen fertilizers are divided into six groups:

• ( , );
• (, ammonium chloride);
• Amide ();
• (, (CAS);

Nitrate fertilizers

Nitrate fertilizers contain in nitrate form (NO 3 -). This group includes NaNO 3 and Ca (NO 3) 2.

Nitrate fertilizers are physiologically alkaline and shift the soil response from acidic to neutral. Due to this property, their use is very effective on acidic soddy-podzolic soils. Not recommended for use on saline soils.

Nitrogen fertilizers (by forms of nitrogen)

Ammonium fertilizers are substances containing NH 4 + in the form of an ammonium cation.

These include ammonium sulfate (NH 4) 2 SO 4, ammonium-sodium sulfate (NH 4) 2 SO + Na 2 SO 4 or Na (NH4) SO4 * 2H2O), ammonium chloride NH 4 Cl.

The production of ammonium fertilizers is simpler and cheaper than nitrate fertilizers, since the oxidation of ammonia to nitric acid is not required.

all over the world it is used in irrigated agriculture for rice and cotton, especially in areas of excessive moisture, in particular in the tropics. In Russia, ammonium sulfate has been produced since 1899. It was first obtained in Donbass, at the Shcherbinsky mine by capturing and neutralizing ammonia with sulfuric acid, which is formed during the coking of coal. A schematic diagram of this method is used now.

receive as a waste of caprolac production. Effective when applied under beets and other root crops due to the presence of sodium. Recommended for hayfields and pastures.

Ammonium Chloride (Ammonium Chloride)

contains a significant amount of chlorine - 67%, 24-26%. Use under chlorine-sensitive crops (potatoes, tobacco, grapes, onions, cabbage, flax, hemp) as fertilizer or not recommended. It is possible to introduce ammonium chloride under chlorophobic crops only in the fall and in areas of sufficient moisture. In this case, chlorine ions will be washed out of the root layer by atmospheric precipitation.

Ammonium chloride - fine crystalline powder of yellowish or white... At 20 ° C, 37.2 g of the substance is dissolved in 100 m 3 of water. Has good physical properties, does not cake during storage, is low hygroscopic.

Ammonium chloride is produced as a by-product in the production of soda.

Ammonium-nitrate fertilizers contain nitrogen in the ammonium (NH 4 +) and nitrate form (NO 3 -). This group includes ammonium nitrate (NH 4 NO 3), ammonium sulphonitrate ((NH 4) 2 SO 4 * 2NH 4 NO 3 + (NH 4) SO 4), calcium ammonium nitrate (NH 4 NO 3 * CaCO 3).

contains nitrate and ammonium nitrogen in a ratio of 1: 1. It is more correct to call this fertilizer ammonium nitrate, but ammonium nitrate is a more common name. It is the most effective one-component nitrogen fertilizer. Ammonium nitrate is a ballastless fertilizer. The cost of its transportation and application to the soil is much lower than that of other nitrogen fertilizers (with the exception of urea and liquid ammonia). The combination of mobile nitrate nitrogen with less mobile ammonium nitrogen makes it possible to vary the methods, doses and timing of the application of ammonium nitrate, depending on the regional soil and climatic conditions and the characteristics of agricultural cultivation.

(ammonium sulfate nitrate, montane nitrate, lane nitrate) is a grayish fine crystalline or granular grayish substance.

Physicochemical properties fertilizers allow it to be successfully used in various soil and climatic conditions. Potentially acidic.

Calcium ammonium nitrate

- granular fertilizer. The ratio of nitrate to lime varies depending on the brand of fertilizer. It is widely used in Western Europe.

Amide fertilizers

Amide fertilizers contain in amide form (NH 2 -). This group includes urea CO (NH 2) 2. The nitrogen in urea is present in organic form as carbamic acid amide. It is the most common solid nitrogen fertilizer. It is used in all methods of introduction, but it is most effective for.

Liquid ammonia fertilizers are liquid forms of nitrogen fertilizers. This group includes liquid (anhydrous ammonia) NH 3, ammonia water (aqueous ammonia), ammonia. The production of liquid ammonia fertilizers is much cheaper than solid salts.

contains 82.3%. It is the most concentrated ballastless fertilizer. Outwardly, a colorless liquid. The physicochemical properties of the fertilizer vary with temperature the environment... It is stored only in sealed vessels, where it is separated into liquid and gaseous phases under pressure.

During transportation, containers are not completely filled. The substance is neutral to cast iron, iron and steel, but strongly corrodes zinc, copper and their alloys.

- ammonia solution in water, low vapor pressure, does not destroy ferrous metals. Nitrogen is contained in the form of ammonia NH 3 and ammonium NH 4 OH. There is much more free ammonia than ammonium. This promotes nitrogen losses through volatilization. It is easier and safer to work with ammonia water than with anhydrous ammonia, but due to the low nitrogen content, its use is profitable only in farms located near the factories that produce it.

Ammonia

contain from 30 to 50% nitrogen. Outwardly, it is a light yellow or yellow liquid. Ammoniates are obtained by dissolving ammonium nitrate, ammonium and calcium nitrate, urea or ammonium nitrate and urea in aqueous ammonia.

Ammoniases differ in the concentration of total nitrogen, in the ratio of its forms and are varied in physical and chemical properties.

Ammoniases are corrosive to copper alloys. Ammoniases with ammonium nitrate also oxidize ferrous metals. Storage and transportation of ammonia is possible in containers made of aluminum, its alloys, of stainless steel or in conventional steel tanks with anti-corrosion epoxy resin coating. It is possible to use containers made of polymeric materials.

(CAS)

- a mixture of aqueous solutions of urea and ammonium nitrate. UAN have a neutral or slightly alkaline reaction. Outwardly - transparent or yellowish liquids. By changing the ratio of the starting components, various grades of CAS are obtained.

Behavior in soil

All one-component nitrogen fertilizers are highly soluble in water.

Nitrate forms

they move along with the soil solution and are bound in the soil only by the biological type of absorption. Biological absorption is active only during the warm season. From late autumn to early spring, nitrates easily move in the soil and can be washed out under the conditions of a leaching water regime, which is especially typical for light soils.

In the warm season, ascending moisture flows prevail in the soils. Plants and microorganisms actively absorb nitrate nitrogen.

Ammonia and ammonia

forms in the soil are absorbed by the soil complex (PPC) and pass into an exchange-absorbed state. In this form, the mobility of nitrogen is lost, and it is not washed out. The exception is light soils with low absorption capacity.

Further nitrification processes promote the transformation of nitrogen into nitrate forms and its biological absorption by plants and soil microorganisms.

With urea

after its transformation under the influence of urobacteria into ammonium forms of nitrogen, the same thing happens.

Thus, nitrogen fertilizers initially or in the process of nitrification accumulate in the soil in a nitrate form, which subsequently undergoes denitrification. These processes occur in almost all types of soils, and it is with them that the main nitrogen losses are associated.

From an agronomic point of view, denitrification is a negative process. But on the environmental side, it plays a positive role, since it frees the soil from nitrates not used by plants and reduces their entry into wastewater and water bodies.

Application on various types of soils

The efficiency of nitrogen fertilization depends on the soil and climatic conditions of the region. The highest efficiency of nitrogen fertilizers is observed in areas of sufficient moisture.

Humus-poor sod-podzolic soils, gray forest soils, podzolized, leached chernozems

... The effect of nitrogen fertilizers is consistently positive. Moreover, with an increase in the degree of leaching of chernozems, the efficiency of nitrogen fertilizers also increases.

Sandy loam, sandy soils

the non-chernozem zones experience an acute shortage of nitrogen, therefore, there is a high efficiency of the action of nitrogen fertilizers. However, under the conditions of the soil leaching regime, significant nitrogen losses are noted, and its application is carried out mainly in the spring.

Drained peat bog soils

... The effect of nitrogen fertilizers is reduced, since phosphorus and potash fertilizers are at a minimum. However, in the first years of the development of peatlands in the central and northwestern regions of the non-chernozem zone, the efficiency of nitrogen fertilizers also increases.

Podzolized and leached chernozems

of the right-bank forest-steppe of Ukraine show greater efficiency in the use of nitrogen fertilizers than the left-bank one.

Leached chernozems of the European part of Russia

... There is a lower efficiency of nitrogen fertilizers in the Volga region. In the Central Black Earth Zone and in the North Caucasus, it is slightly higher.

In the steppe zone

with an increase in climate aridity, the effect of nitrogen fertilizers decreases or becomes very unstable. But under irrigation conditions, the effectiveness of the action of nitrogen fertilizers increases and is even higher than that of phosphorus and potassium fertilizers.

Typical black soil

Moldova is distinguished by large yield increases.

Ordinary and carbonate chernozems

Moldova is characterized by a lower efficiency of single-component nitrogen fertilizers.

Ordinary chernozems

steppe regions of Ukraine... Nitrogen fertilizers show significant effectiveness, but the effect is also significantly weakened from west to east.

Ordinary and carbonate chernozems of the Kuban, foothills of the North Caucasus, northern Azov chernozems

are distinguished by a significant positive effect of nitrogen fertilizers.

Carbonate chernozems of the Rostov region, ordinary chernozems of the Volga region

... Fertilizer efficiency decreases.

Chestnut soils

... At better conditions moisturizing, a good effect of fertilizers is noted. In dry conditions, the effect of nitrogen fertilizers is weak.

Impact on crops

Nitrogen fertilizers play a leading role in increasing the productivity of various agricultural crops. This is due to the role of nitrogen as an important biological element that plays an exceptional role in plant life.

Adequate nitrogen supply enhances the synthesis of organic nitrogenous substances. Plants develop powerful leaves and stems, the intensity of the green color increases. Plants grow and bush well, the formation and development of fruiting organs is improved. These processes contribute to higher yields and protein content.

However, it must be borne in mind that a one-sided excess of nitrogen can delay the maturation of plants, contributing to the development of vegetative mass while reducing the development of grains, roots or tubers. In flax, cereals and some other crops, excess nitrogen causes lodging (Photo) and deterioration in the quality of crop production.

Thus, the starch content in potato tubers may decrease. In sugar beet roots, sugar content decreases and the content of non-protein nitrogen increases.

With an excess of nitrogen fertilizers in feed and vegetables, nitrates, potentially hazardous to human and animal health, accumulate.

Obtaining nitrogen fertilizers

The production of nitrogen fertilizers is based on the production of synthetic ammonia from molecular nitrogen and hydrogen.

Nitrogen is formed when air passes through a generator with burning coke.

Sources of hydrogen - natural gas, petroleum or coke oven gases.

Ammonia is formed from a mixture of nitrogen and hydrogen (ratio 1: 3) at high temperature and pressure and in the presence of a catalyst:

N 2 + 3H 2 → 2NH 2

Synthetic ammonia is used for the production of ammonium nitrogen fertilizers and nitric acid, which is used to obtain ammonium-nitrate and nitrate fertilizers.

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Yagodin B.A., Zhukov Yu.P., Kobzarenko V.I. Agrochemistry / Edited by B.A. Yagodina .- M .: Kolos, 2002 .- 584 p .: silt (Textbooks and tutorials For university students).

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Nitrogen fertilizers are inorganic and organic substances that contain nitrogen and are applied to improve yields. Nitrogen is the main element of plant life, it affects the growth and metabolism of crops, saturates them with useful and nutritious components.

This is a very powerful substance that can both stabilize the phytosanitary state of the soil, and have the opposite effect - in case of its overabundance and improper use. Nitrogen ones differ in the amount of nitrogen they contain and are classified into five groups. The classification of nitrogen fertilizers implies that nitrogen can take different chemical forms in different fertilizers.

The role of nitrogen in plant development

The main reserves of nitrogen are contained in the soil () and amount to about 5%, depending on specific conditions and climatic zones. The more humus in the soil, the richer and more nutritious it is. Light sandy and sandy loam soils are considered the poorest in terms of nitrogen content.

However, even if the soil is very fertile, only 1% of the total nitrogen contained in it will be available for plant nutrition, since the decay of humus with the release of mineral salts is very slow. Therefore, nitrogen fertilizers play an important role in crop production, their importance cannot be underestimated, because it will be extremely problematic to grow a large and high-quality crop without their use.

Nitrogen is an important component of protein, which, in turn, participates in the formation of the cytoplasm and nucleus of plant cells, chlorophyll, most vitamins and enzymes that play an important role in the processes of growth and development. Thus, a balanced nitrogen nutrition increases the percentage of protein and the content of valuable nutrients in plants, increasing the yield and improving its quality. Nitrogen as fertilizer used for:

• accelerating plant growth;
• saturation of the plant with amino acids;
• an increase in the volumetric parameters of plant cells, a decrease in the cuticle and shell;
• accelerating the process of mineralization of nutrients introduced into the soil;
• activation of the state of soil microflora;
• extraction of harmful organisms;
• increasing yields

How to determine the lack of nitrogen in plants

The amount of nitrogen fertilizers applied directly depends on the composition of the soil on which the plants are cultivated. Insufficient nitrogen content in the soil directly affects the viability of the crops grown. Lack of nitrogen in plants can be determined by their appearance: the leaves become smaller, lose color or turn yellow, die off quickly, growth and development slows down, and young shoots stop growing.

Ammonium sulfate

Ammonium sulfate contains up to 20.5% nitrogen, which is readily available to plants and is fixed in the soil due to the cationic nitrogen content. This allows you to apply fertilizer in the fall, without fear of possible significant losses of minerals due to leaching into groundwater. Ammonium sulphate is also suitable as a base and top dressing application.

It has an acidifying effect on the soil, therefore, as in the case of nitrate, 1.15 kg of a neutralizing substance (chalk, lime, dolomite, etc.) must be added to 1 kg of ammonium sulfate. According to research results, fertilizer has an excellent effect when used for feeding. Ammonium sulfate is not picky about storage conditions, since it is not humidified as much as ammonium nitrate.

Important! Do not mix ammonium sulfate with alkaline fertilizers: ash, slag, slaked lime. This leads to nitrogen losses.

Potassium nitrate

Or potassium nitrate is a mineral fertilizer in the form of white powder or crystals, which is applied as an additional nutrition for crops that are not tolerant of chlorine. It contains two main components: potassium (44%) and nitrogen (13%). This ratio with the prevalence of potassium can be used even after flowering and ovary formation.

This composition works very well: thanks to nitrogen, the growth of crops is accelerated, while potassium increases the strength of the roots so that they more actively absorb nutrients from the soil. Due to biochemical reactions, in which potassium nitrate acts as a catalyst, the respiration of plant cells is improved. This activates plant immunity, reducing the risk of many diseases.

This effect has a beneficial effect on increasing yields. Potassium nitrate is highly hygroscopic, that is, it easily dissolves in water for the preparation of plant nutrition solutions. The fertilizer is suitable for both root and foliar dressing, in dry and liquid form. The solution acts much faster, so it is more often used for feeding.

In agriculture, potassium nitrate is mainly fed, tobacco, etc. But, for example, he loves phosphorus, so this fertilizer will be ineffective for him. It makes no sense to add potassium nitrate under the greens, and since such use of fertilizer will be irrational.

The effect of nitrogen fertilizers in the form of potassium nitrate on plants is to improve the quality and increase the amount of the crop. After fertilization, the pulp of the fruit is fully saturated with fruit sugars, and the size of the fruit itself increases. If you feed at the stage of setting the ovaries, then the fruits will subsequently increase the shelf life of the fruits, they will retain their original appearance, useful and taste qualities for a longer time.

Calcium nitrate, calcium nitrate or calcium nitrate is a fertilizer that comes in the form of granules or crystalline salt and dissolves well in water. Despite the fact that this is a nitrate fertilizer, subject to dosages and recommendations for use, it does not harm human health and brings great benefits to agricultural and horticultural crops.

In the composition - 19% calcium and 13% nitrogen. The good thing about calcium nitrate is that it does not increase the acidity of the soil, unlike most other types of fertilizers that contain nitrogen. This feature allows the use of calcium nitrate on different types of soil. The fertilizer works especially effectively on sod-podzolic soils.

It is calcium that contributes to the full assimilation of nitrogen, which ensures good growth and development of crops. With a lack of calcium, the root system of the plant suffers, first of all, which lacks nutrition. The roots stop receiving moisture and rot. Of the two existing aggregate forms of calcium nitrate, it is better to choose granular, it is more convenient to handle, does not spray during use and does not absorb moisture from the air.

The main advantages of calcium nitrate:

• high-quality formation of green mass of plants by strengthening the cells;
• acceleration of germination of seeds and tubers;
• recovery and strengthening of the root system;
• increased resistance to disease, bacteria and fungi;
• increasing the winter hardiness of plants;
• improving the taste and quantity of the yield.

Did you know? Nitrogen helps well in the fight against insect pests of fruit trees, for which urea is often used as. Before the buds bloom, the crown must be sprayed with a urea solution (50-70 g per 1 liter of water). This will save the plants from overwintering in the bark or in the soil near the trunk circle. Do not exceed the dosage of urea, otherwise it will lead to leaf burns.

Sodium nitrate, sodium nitrate or sodium nitrate is used not only in plant growing and agriculture, but also in industry. These are solid white crystals, often with a yellowish or grayish tint, readily soluble in water. The nitrogen content in the nitrate form is about 16%.

Sodium nitrate is obtained from natural deposits using the crystallization process or from synthetic ammonia, which contains nitrogen. Sodium nitrate is actively used on all types of soils, especially under, and, vegetable crops, fruit and berry and flower crops with early spring application.

It works most effectively on acidic soils, since it is an alkaline fertilizer, it alkalizes the soil a little. Sodium nitrate has proven itself as a top dressing and use for sowing. Fertilizer is not recommended to be applied in autumn, as there is a risk of nitrogen leaching into groundwater.

Important! It is forbidden to mix sodium nitrate and superphosphate. It is also impossible to use it on salt licks, since they are already oversaturated with sodium.

- crystalline granules with a high nitrogen content (up to 46%). The plus is that the nitrogen contained in urea, easily soluble in water, wherein useful material do not go into the lower soil layer. It is recommended to use urea as a foliar dressing, since it has a gentle effect and does not burn the leaves, if the dosage is observed.

Thus, urea can be applied during the growing season of plants, it is suitable for all types and times of application. Fertilizer is used before sowing, as the main top dressing, by deepening the crystals into the soil so that ammonia does not evaporate in the open air. During sowing, it is recommended to apply urea together with potash fertilizers, this helps to eliminate the negative effect that urea can have due to the presence of the harmful substance biuret in its composition.

Foliar dressing is carried out using a spray bottle in the morning or evening. A solution of carbamide (5%) does not burn the leaves, unlike ammonium nitrate. The fertilizer is used on all types of soils for feeding flowering crops, fruit and berry plants, vegetables and root crops. Urea is introduced into the soil two weeks before sowing so that the biuret has time to dissolve, otherwise the plants may die.

Important! Do not allow liquid nitrogen-containing fertilizers to get on plant leaves. This causes them to burn.

Liquid nitrogen fertilizers

They gained wide popularity due to their affordable price: at the output, the product is 30 - 40% cheaper than its solid counterparts. Consider the main issues liquid nitrogen fertilizers:

• Liquid ammonia is the most concentrated nitrogen fertilizer, containing up to 82% nitrogen. It is a colorless mobile (volatile) liquid with a specific pungent smell of ammonia. To carry out top dressing with liquid ammonia, special closed machines are used, placing the fertilizer at a depth of at least 15-18 cm so that it does not evaporate. Store in special thick-walled tanks.
• Ammonia water, or aqueous ammonia - produced in two types with different percentages of nitrogen 20% and 16%. Just like liquid ammonia, ammonia water is brought in by special machines and stored in closed high-pressure tanks. In terms of efficiency, these two fertilizers are equal to solid crystalline nitrogen-containing fertilizers.
• Ammonia - obtained by dissolving combinations of nitrogen fertilizers in aqueous ammonia: ammonium and calcium nitrate, ammonium nitrate, urea, etc. As a result, a yellow liquid fertilizer is obtained, which contains from 30 to 50% nitrogen. In terms of action on crops, ammoniacalates are equated to solid nitrogen fertilizers, but they are not so widespread due to inconvenience in use. Ammoniates are transported and stored in sealed aluminum tanks designed for low pressure.
• Urea-ammonium mixture (UAN) is a very effective liquid nitrogen fertilizer, which is actively used in crop production. UAN solutions have undeniable advantages over other nitrogen-containing fertilizers. The main advantage is the low content of free ammonia, which almost eliminates the loss of nitrogen due to the volatility of ammonia during transportation and introduction of nitrogen into the soil, which is observed when using liquid ammonia and ammonia. Thus, there is no need to create complex pressurized storage and transportation tanks.

All liquid fertilizers have their own advantages over solid fertilizers - better digestibility by plants, a longer period of action and the ability to evenly distribute the fertilizing.

Organic nitrogen fertilizers

Nitrogen is found in small quantities in almost all types of organic fertilizers. Manure contains about 0.5-1% nitrogen; 1-1.25% - (its highest content is in chicken, duck and pigeon droppings, but they are also more toxic).

Organic nitrogen fertilizers can be prepared independently: based heaps contain up to 1.5% nitrogen; in the compost from household waste about 1.5% nitrogen. Green mass (clover, lupine, sweet clover) contains about 0.4-0.7% nitrogen; green foliage - 1-1.2% nitrogen; lake silt - from 1.7 to 2.5%.

It is worth remembering that using organics alone as a nitrogen source is ineffective. This can deteriorate the quality of the soil, acidify it and not provide the necessary nitrogen nutrition for crops. It is best to give preference to the use of a complex of mineral and organic nitrogen fertilizers to achieve the maximum effect for plants.

Precautionary measures

When working with nitrogen fertilizers, be sure to follow the instructions for use, follow the recommendations and not violate the dosage. Second important point- This is the presence of closed, tight clothing so that drugs do not get on the skin and mucous membranes.

Liquid nitrogen fertilizers are especially toxic: ammonia and ammonia water. Strict adherence to safety rules when working with them is imperative. The ammonia water storage tank should be no more than 93% full to avoid heat spill. Only persons in special protective clothing who have passed a medical examination, training and instruction are allowed to work with liquid ammonia. Thank you for your opinion!

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helped

The use of nitrogen fertilizers is a prerequisite for growing healthy and robust plants. The main element of such substances is nitrogen, which is essential for their proper development. It is one of the most important substances that plants use.

Purpose of nitrogen fertilizers

Nitrogen fertilizers are used to enrich any soil with mineral compounds, regardless of its composition and pH indicators. The only difference is that it is necessary to take into account the amount of fertilizer applied for different soil compositions. So, for the poorer sandy ones you will need large quantity and the frequency of application, and on chernozems, its consumption will be much less.

The first signals for their application are appearance plants. With a lack of nitrogen, the leaves on them lose their brightness, turn yellow and fall for no reason, weak development and the formation of new shoots are observed.

Of course, these signs are a signal for the strongest depletion of the soil, and it is necessary to apply mineral fertilizing before they appear. There are three types of nitrogen fertilizers, these are:

• Ammonia.
• Nitrate.
• Amide.

Features and types of nitrogen fertilizers

The most widely used fertilizers are ammonium nitrate and ammonium sulfate.

Nitrate compounds are used less often, but at the same time they have undeniable advantages - they do not acidify the soil, which is sometimes extremely important for some plant species. This group includes potassium and sodium nitrate.

Amide - this is the most famous type of nitrogen fertilizers in a wide circle of gardeners and farmers. A prominent representative of this group is urea.

Application

Nitrogen fertilizers are applied to the soil when planting plants and further fertilizing. They can also be applied to enrich the soil with minerals during plowing periods.

Nitrogen fertilizers are used both for growing fruit and vegetable crops and for indoor plants. First of all, nitrogen contributes to the development and growth of green mass, and an excessive amount can lead to a delay in the flowering of plants. It is important to take into account that plants with woody, bulbous or branched root systems are more in need of nitrogen, which they begin to apply from a very young age, and root crops are not fertilized in the initial period, starting these processes only after the appearance of stronger foliage.

It should also be remembered that, having an artificial origin, such formulations can harm plants if they are not properly dosed and used haphazardly.

Despite the fact that nitrogen fertilizers are of three types, there are several more subspecies of their compounds.

Ammonium and ammonia fertilizers

Ammonium sulfate is a fertilizer that contains 21% nitrogen, is easily soluble in water, practically does not cake. It is also a valuable supplier of sulfur, which is contained in this compound in an amount of 24 percent. In composition, it is a neutral salt, however, when absorbed by plants, it is an acidifying substance. Therefore, the use on acidic soils must be well calculated in terms of dosage, or it must be replaced by other means. They should be used with caution on the following soils: brown, gray forest, red soils, sod-podzolic, yellow soils. In these lands, ammonium sulfate is used only in combination with alkaline phosphorus fertilizers such as phosphate rock, lime or slag.

On chernozemic and semi-desert soils, you should not be afraid of soil acidification when using ammonium sulfate, since they contain a lot of free carbonates that neutralize its effect.

Ammonium chloride is a crystalline substance containing about 25% nitrogen. Let's well dissolve in water, slightly hygroscopic. Like ammonium sulfate, it gives the soil acidity, therefore it has the same number of contraindications for use and must be combined with the use of alkaline fertilizers to neutralize.

It is necessary to be very careful, only within the framework of the manufacturer's recommendation, to use ammonium chloride, since the chlorine contained in it is difficult to tolerate by some plants, which may die from its effects. These sensitive crops include: potatoes, grapes, buckwheat, citrus fruits, flax, tobacco, vegetables and fruits and vegetables. Cereals and winter crops equally respond to fertilizers.

Nitrate fertilizers

This group of fertilizers includes sodium and calcium nitrate. These are alkaline compounds that work well on acidic soils, and they can also be used in conjunction with other substances that have an acidic reaction.

Sodium nitrate contains about 16% nitrogen. Organoleptic characteristics: white crystalline powder, hygroscopic, easily soluble in water. Most often, this fertilizer is used for growing root crops, for which it is applied to the soil in a dry form even during planting, and then the plants are watered directly with a solution of weak concentration.

Potassium nitrate contains 15% nitrogen. Easily soluble in water and has an increased level of hygroscopicity, which is an indication for storage in tightly packed cellophane bags. It is one of the most suitable fertilizers for acidic soils or neutralizing other acidifying compounds.

Ammonium nitrate fertilizers

This group includes ammonium and lime-ammonium nitrate.

The total nitrogen content in this substance is 35%. Ammonium nitrate is highly hygroscopic and should therefore be stored in tightly sealed, waterproof bags. When applied to the soil, it is necessary to mix it with freshly slaked lime, where the content will reach the proportions of 7: 3. This method is most often used for machine fertilization of fields. The production of nitrogen fertilizers is carried out with the addition of a substance that is a baking powder and absorber of excess moisture, these include: chalk, ground limestone, phosphate rock.

Ammonium nitrate is easily soluble in water, and therefore during watering it is not diluted with water in advance, it is introduced dry into the soil when planting plants. Independent application on acidic soils is undesirable, as it further aggravates their PH-reaction.

Ammonium nitrate can be used both during planting and in secondary fertilization of plants. Most often they are used for growing potatoes, beets, cereals, winter crops and row crops.

Calcium ammonium nitrate contains about 20% nitrogen in its composition, and due to the content of calcium carbonate it is a more favorable fertilizer for plants than ammonium nitrate.

Amide fertilizers

Amide fertilizers include urea, which ranks second in terms of nitrogen content. Its amount is 46%. Release form - granules, covered with a film, which contains fats that do not allow the substance to cake. When using urea, the superficial spread of the fertilizer is not allowed. This is due to the fact that, by reacting with soil bacteria, it is converted into ammonium carbonate. This is the simplest and most readily available form for absorption by plants. However, do not forget that, interacting with atmospheric oxygen, it decomposes, including into gaseous ammonia, and the efficiency of fertilization decreases with its evaporation.

Urea is universal in its application and significantly increases the productivity of various crops. It is especially preferable to use it on soils subject to stable moisture, since it tends to be washed out with water less than other substances.

Calcium cyanamide. Nitrogen content 20%, absolutely insoluble in water, dark gray powder, is an alkaline fertilizer. It is in connection with the high content of calcium in the composition of the fertilizer that it is recommended to use it on acidic soils, which are well neutralized by this composition. However, it is worth limiting its use or using it in combination with acidic fertilizers on alkaline soils. It is extremely important to apply this fertilizer in advance, before sowing, since when interacting with the soil and its bacteria, cyanamide is formed, which can weaken the plants or even lead to their death. But over time, this substance is processed into urea. This will take at least 10 days, so fertilizers are applied well in advance, even before sowing. Fertilizers are also used as an additional top dressing, which is applied in early spring or autumn directly to the soil.

Liquid fertilizers

Anhydrous ammonia ranks first in terms of nitrogen content - 82.3%. The process of its production is rather complicated, the substance is obtained by liquefying ammonia gas. Anhydrous ammonia cannot be stored in open containers, as it tends to evaporate, and also leads to corrosion of metals such as zinc and copper, but does not affect steel, iron and cast iron, and therefore fertilizer is stored in thick-walled tanks from these metals.

Ammonia water - this fertilizer is a solution of ammonia in water, where nitrogen is contained in an amount of 15-20%. Storage does not involve special costs. Ammonia water does not react with ferrous metals and can be stored in conventional carbon steel containers.

These nitrogen fertilizers are applied directly to the soil to a depth of about ten centimeters, which is carried out using special machines and is carried out both in the spring before the start of sowing and in the fall, after the harvest and the start of plowing. Most often they are used for feeding tilled crops.

Ammonia. In industrial conditions, they are obtained by dissolving solid forms, such as all types of saltpeter and urea. The nitrogen content in such solutions reaches 50%. For storage, you will need special sealed tanks made of aluminum, or containers made of polymers.

Ammoniases act in the same way as solid nitrogen fertilizers, the names and properties of which are mentioned in this article.

Urea-formaldehyde fertilizers

This group of delayed-action nitrogen fertilizers is characterized by a low ability to dissolve in water, due to which a long-acting effect is achieved and most of the nitrogen is retained. It is especially advantageous to use them on large areas, since a concentrated application to the soil is possible, which will not threaten oversaturation due to their low dissolution capacity. In this regard, the costs of attracting the necessary labor and financial resources to fertilize the soil are reduced.

This group also includes encapsulated nitrogen fertilizers. They are made using the technology of conventional, water-soluble nitrogen fertilizers, which are coated with special compounds that slow down the distribution of minerals in the earth. As such protective layers are used: emulsion of polyethylene, acrylic resin or sulfur, which also helps to reduce the cost of fertilization and long-term effects on plants.

Nitrogen and phosphorus fertilizers, when applied to the soil, tend to nitrify. This leads to environmental pollution and leaching of such compounds during irrigation or precipitation. This process also decomposes the nitrogen they contain. This inevitably leads to a loss of concentration and means a decrease in the level of consumption of it by plants. In order to neutralize this process and to combat its consequences, nitrification inhibitors are used. They can be added both in solid and in liquid form, in a dosage of 0.5-3% of the total amount of nitrogen contained in this type of fertilizer.

With such a mutually beneficial application, the nitrification process will last up to two months, reaching its peak during the period when the plant root system is sufficiently strong and has managed to sufficiently absorb the nitrogen contained in the fertilizer. This method of using nitrogen fertilizers in combination with nitrification inhibitors significantly increases the yield of crops grown. There is also a high increase in product quality and a decrease in the percentage of nitrates in it. Nitrogen fertilizers, the names or composition of which bears an indication of the content of nitrification inhibitors, are the safest and most effective to use. This also leads to significant savings in the processing of large areas and a decrease in the doses of fertilizers used, which directly affects the quality and cost of production.

Nitrogen fertilizers and their application

Fertilizers of nitrogen origin dissolve quite easily in water and are therefore quickly delivered to the root system of plants. Therefore, the most effective and acceptable method of using them is to apply them to the soil or directly under the roots of the plant in the spring, when the lack of this substance is most pronounced during the development of young plants. The decision about which nitrogen fertilizers should be applied in each specific case must be well reasoned and weighed.

It is not recommended to bring them in in the fall, this restriction applies to perennial trees and shrubs, as this can reduce their frost resistance and in the event of severe cold weather, the plants may die. Nitrogen fertilizers will only be beneficial in the spring. They are especially carefully used for fruit trees, since an overabundance can lead to an extension of the flowering and ripening period of fruits, and foliage can also remain on the branches for a long time, up to frost, which will inevitably lead to damage to the shoots and weakness of the buds being laid.

When applying nitrogen fertilizers to shrubs and trees, the prescribed dose is reduced by half.

Just like animals and humans, plants constantly need to feed. The best way to provide them with all the necessary trace elements will be fertilizing with nitrogen fertilizers in combination with the use of organic fertilizers. This approach will provide the gardener with healthy plants and high yields from every square meter of land.