The criterion for the environmental safety of a fertilizer application system and its impact on soil fertility is the balance of the most important nutrients - nitrogen, phosphorus and potassium. Nutrient balance is a quantitative expression of the content of nutrients in the soil on a specific soil or object of study, taking into account all items of their intake and consumption over a certain period of time [V.G. Mineev, 2012].
The balance of nitrogen, phosphorus and potassium has its own characteristics. Nitrogen in the soil-fertilizer-plant system is highly mobile. Another feature of nitrogen balance is its biological fixation by symbiotic and free-living microorganisms.
Phosphorus has no natural sources of replenishment in the soil. Losses occur mainly due to soil erosion. Phosphate disposal occurs mainly through agricultural crops.
Potassium balance is characterized by large soil resources. However, with long-term agricultural use, the content of exchangeable potassium available to plants has decreased to an average supply level, therefore potassium fertilizers are an essential component of the fertilizer system, and the potassium balance serves as an important indicator of its effectiveness in preserving and increasing soil fertility.
The balance of nutrients in crop rotation can be positive or negative and is calculated to determine the possible enrichment or depletion of the soil with certain nutrients.
As mentioned above, the main source of alienation of nutrients from the soil is the harvest of agricultural crops. To determine the amount of substance removed by crop rotation crops, we draw up a table indicating the planned yield and the total amount of nitrogen, phosphorus and potassium removed.
Crop rotation crops Yield, t/ha Removal with crop yields, kg/ha N P K Fallow - - - - Wheat 1.1 38.5 16.5 28.6 Wheat 1.1 38.5 16.5 28.6 Corn 27, 2 81.6 40.8 103.4 Barley 0.9 27.0 10.8 25.2 Rump 4.6, 71.8 17.94 92.0 Total 257.4 102.54 277.8
The data obtained should be taken into account in the expenditure part of the nutrient balance.
The balance of nutrients is based on crop rotation. For nitrogen, the following items of receipt (income) and expenditure (expense) are accepted:
Income, kg/ha.
- 1 Nitrogen in organic fertilizers: 220.0.
- 2 Nitrogen of mineral fertilizers: 45.0.
- 3 Nitrogen input from precipitation: 2.0.
- 4 Nitrogen fixation by free-living microorganisms: 30.0.
Total income, kg/ha: 279.0.
Consumption, kg/ha.
- 1 Removal with crop harvest: 257.4.
- 2 Gaseous losses of nitrogen from applied mineral fertilizers: 11.25.
- 3 Gaseous losses from organic fertilizers: 44.0.
- 4 Nitrogen losses due to infiltration and soil erosion: 9.9.
Total consumption, kg/ha: 322.6.
Balance: -25.6 kg/ha.
The balance of phosphorus and potassium is determined by the following indicators:
Income, kg/ha.
- 1 With mineral fertilizers: 79.0; 79.0.
- 2 With organic fertilizers: 88.0; 264.0.
Total income, kg/ha: 167.0; 343.0.
Consumption, kg/ha.
- 1 Removal with harvest: 102.54; 277.8.
- 2 Erosion losses: 4.2; 9.6.
Total consumption: 106.74; 287.4.
Balance: 60.3; -55.6.
As a result of the calculations, the nitrogen balance turned out to be negative, but not exceeding 40% of the consumption. A positive nitrogen balance or close to 0 negatively affects the quality of the resulting product. The soil is polluted with nitrates, a significant part of which ends up in products. The accumulation of nitrates in feed has a negative effect on animals and leads to poisoning of the body, disruption of general health and, as a consequence, to the loss of a significant amount of livestock products.
The phosphorus balance should be much less positive, close to zero. An excessive excess of phosphorus increases the risk of contamination of soil and products with unwanted (toxic) elements accompanying it in fertilizers (fluorine, chromium, nickel, lead, cadmium, etc.), and also reduces the availability of zinc to plants (Yu.P. Zhukov, 2004). In addition, phosphorus fertilizers are the most expensive and using large doses will increase costs and, as a consequence, the cost of production.
In order to reduce the phosphorus balance, it is necessary to reduce the amount of the element in the incoming part of the balance. By reducing the rate of applied fertilizers to 19 kg a.m./ha, we bring the phosphorus balance closer to zero.
The potassium balance can be zero or slightly negative, since ordinary chernozems contain enough large number element. Excess potassium increases the risk of contamination of products and contributes to more intensive leaching of calcium and magnesium from the arable soil layer.
Balance of nutrients in the soil
The balance of nutrients is a mathematical expression of the cycle of nutrients in agriculture. Determining the balance of nutrients is the scientific basis for planning and forecasting the use of mineral fertilizers, their distribution between regions and farms, allows you to purposefully regulate fertility, and protect the environment from pollution by fertilizers. The balance of basic nutrients reflects the degree of intensification of agricultural production.
The balance of nutrients in the “fertilizer-soil-plant” system is assessed by the difference between their total amount supplied to the soil and removed from it. Thus, the balance of nutrients in the soil consists of incoming and outgoing parts. IN credit side of the balance sheet admission included nutrients into the soilwith fertilizers, seeds, from atmosphere, including nitrogen, produced nodule bacteria legumes (symbiotic) and free-living bacteria - nitrogen fixers (non-symbiotic nitrogen). Expense part of the balance includes household takeout nutrients(with part of the harvest alienated from the field), loss of batteries from soil and fertilizers with surface water from leaching, erosion, evaporation and gaseous losses (nitrogen).
As a result of agricultural use, soils undergo significant changes, and the intensity of the processes of transformation and migration of nutrients, consumption and removal by plants changes. The amount of consumption and loss of nutrients depends on the granulometric composition and degree of cultivation of the soil, the nature of its agricultural use, the type, doses and timing of use of fertilizers, agricultural practices and other conditions. This makes it necessary to periodically clarify the incoming and outgoing items of the balance of batteries. To objectively characterize the degree of provision of planned crops with nutrients, it is advisable to have balance calculations for at least 5 years.
There are several types of nutrient balance: full(either biological or environmental), foreign economic, economic And effective.
Full balance gives a complete picture of the cycle of elements, since it takes into account all sources of nutrients entering the soil (with fertilizers, seeds, from the atmosphere, biological nitrogen) and all items of consumption of nutrients (removal with the main and by-products alienated from the field, content in root and post-harvest residues, surface runoff, leaching and gaseous losses).
At foreign economic balance the amount of nutrients alienated from the territory of the farm with commercial crop and livestock products is compared, and their supply with mineral fertilizers, mixed feed, organic fertilizers purchased by the farm (peat, sapropels, lignin, peat-manure composts, etc.). The foreign economic balance is influenced by the specialization of the economy. Thus, in farms specializing in the production of livestock products and using their own feed, 80–90% of potassium, 60–70% of phosphorus and 40–50% of nitrogen carried out with feed are returned to the soil with organic fertilizers. In grain farms, 60–80% of nitrogen, 70–85% of phosphorus and 15–35% of potassium removed by the harvest are removed from the farm territory.
To characterize the balance, the indicator is used intensity balance–the ratio of the supply of batteries to their consumption. The intensity of the balance is expressed as a percentage or coefficients. A balance intensity value of less than 100% characterizes a deficit balance, 100% – a deficit-free balance, and more than 100% – a positive balance. Intensity of the balance of nitrogen, phosphorus and potassium on arable land in Belarus for 2001–2005. was for nitrogen - 116, phosphorus - 123, potassium - 127%.
A deficient balance of nutrients (excess of consumption over supply) warns that soil depletion and a decrease in their fertility are occurring.
The alienation of nitrogen, phosphorus and potassium from agricultural production with commercial crop and livestock products must be fully compensated by the application of mineral fertilizers.
Economic balance nutrients is compiled to evaluate the fertilizer application system. Let's give methodology its calculation, developed by the Institute of Soil Science and Agrochemistry. Incoming balance sheet items: supply of nutrients with mineral fertilizers; with organic fertilizers; symbiotic nitrogen; with seeds; with precipitation; non-symbiotic nitrogen. Balance sheet expense items nutrients: removal by planned harvests; losses from leaching (leaching); losses from soil erosion; gaseous nitrogen losses.
Quantity nutrients supplied With mineral fertilizers, determined by doses for crops and found average value per 1 hectare of crop rotation area. Arrival from organic fertilizers are found according to saturation of crop rotation with organic fertilizers.
Example. The saturation of organic fertilizers in crop rotation is 12 t/ha. From 1 ton of cattle manure on a straw bedding, 5.0 kg of nitrogen enters the soil (Table 14.11), and from 12 tons - 60.0 kg, phosphorus - 30.0 kg (2.5 ∙ 12), potassium - 72.0 kg (6.0 ∙ 12).
To determine the quantity biological nitrogen use data on the amounts of nitrogen fixed from the atmosphere remaining in the soil after legumes. Thus, per 1 centner of green mass, symbiotic nitrogen remains in the soil in excess of that absorbed by plants: after perennial leguminous grasses (except alfalfa) - 0.35 kg, alfalfa - 0.40, after perennial legume-cereal mixtures - 0.20 kg , after annual legume grasses - 0.25 kg, annual legume-cereal grass mixtures - 0.20 kg. Legume-cereal grasses of hayfields and pastures leave 0.15 kg of nitrogen in the soil per 1 centner of green mass. For 1 quintal of lupine grain pure form fixes 5.0 kg, broad beans - 3.0, peas, pelyushka, vetch, soybean in pure form - 2.5, lupine mixed with grain crops - 4.5, peas, pelyushka and vetch mixed with grain crops - 2.0 kg nitrogen.
14.11. Supply of nutrients with organic fertilizers, kg/t
| Type of organic fertilizer | N | R 2 O 5 | K 2 O | SaO | MgO | SO 4 * |
| Cattle manure on straw bedding | 5,0 | 2,5 | 6,0 | 4,0 | 1,1 | 0,2 |
| Cattle manure on peat bedding | 6,0 | 2,0 | 5,0 | 4,5 | 1,0 | 0,5 |
| Peat manure compost: | ||||||
| 1:1 | 5,0 | 1,6 | 4,0 | 3,5 | 0,6 | 0,3 |
| 1:2 | 5,5 | 1,8 | 4,5 | 4,0 | 0,8 | 0,4 |
| Straw (cereals) | 4,0 | 1,5 | 10,0 | 2,0 | 1,0 | 1,5 |
| Liquid cattle manure | 2,0 | 1,0 | 2,5 | 0,5 | 0,4 | 0,1 |
| Liquid pig manure | 2,5 | 0,9 | 1,8 | 0,6 | 0,2 | 0,1 |
| Semi-liquid cattle manure | 3,5 | 1,5 | 4,0 | 1,3 | 0,9 | 0,3 |
| Bird droppings (litter) | 20,0 | 16,5 | 8,5 | 18,0 | 6,0 | 3,5 |
| Peat manure compost: | ||||||
| 1:1 | 10,0 | 8,0 | 3,0 | 9,0 | 3,0 | 1,5 |
| 1:2 | 12,5 | 10,0 | 4,0 | 10,0 | 4,0 | 2,0 |
*Values are determined by calculation.
Example. In a crop rotation of 900 hectares, lupine occupies 100 hectares, clover - 100 hectares. The yield of green mass of lupine is 200 c/ha, clover (green mass) is 200 c/ha. After lupine, 50 kg of nitrogen (200∙0.25) remains in the soil per 1 ha, and 5000 kg per 100 ha. After clover, 70 kg of nitrogen remains per 1 hectare, and 7000 kg per 100 kg. The amount of nitrogen remaining after lupine and clover is divided by the area of arable land in crop rotation and the average amount of symbiotic nitrogen per 1 ha is found: (5000 kg + 7000 kg): 900 = 13.3 kg.
WITH seeds, according to the Institute of Soil Science and Agrochemistry, on average 3 kg/ha of N, 1.3 – P 2 O 5, 1.5 – K 2 O, 0.3 – CaO, 0.1 – MgO, 0.2 kg/ ha S. C precipitation 9.4 kg/ha of N, 0.5 of P2O5, 10.3 of K2O, 25.3 of CaO, 5.0 of MgO and 36 kg/ha of S (SO4) are supplied. Admission nitrogen fixed by free-living bacteria when calculating the balance on arable and grassland lands, it is taken at the level of 15 kg/ha per year.
At calculation of expense items balance is first determined removal of nutrients by planned crops, using the data from table. 2.5, then the values of the removal of basic nutrients on average per 1 hectare of crop rotation area are determined. Losses of nutrients from leaching (leaching) and soil erosion are given in Table. 14.12.
Gaseous nitrogen losses on arable and grassland ranges from 10 to 50% of that applied with fertilizers. Molecular nitrogen, nitrous oxide, nitrogen oxide and dioxide, and ammonia are released into the atmosphere. According to the Institute of Soil Science and Agrochemistry, in Belarus, on average, 25% of the nitrogen introduced with mineral and organic fertilizers evaporates. For each element, a weighted average loss rate is calculated taking into account the amount of eroded soil on the farm.
Example. Of the 2850 hectares of arable land on the farm, 201 hectares are slightly eroded soils, 105 hectares are moderately eroded and 98 hectares are highly eroded soils. The weighted average of nitrogen losses from erosion per 1 hectare of arable land will be equal to (5∙201+ +10∙105 + 15∙98) : 2850 = 1.2 (kg/ha). In hayfields and pastures, the loss of nutrients from leaching and erosion is not taken into account. The sum by expense items shows the consumption of nutrients on average per 1 hectare of crop rotation area.
14.12. Losses of nutrients from leaching and erosion on arable soils, kg/ha
| Soils | N | R 2 O 5 | K 2 O | SaO | MgO | SO 4 |
| Washing losses | ||||||
| Sod-podzolic: | ||||||
| loamy | 0,2 | |||||
| sandy loam on moraine | 0,1 | |||||
| sandy loam on sand | 0,1 | |||||
| sandy | 0,1 | |||||
| Peat | 0,1 | |||||
| Losses from erosion | ||||||
| Degree of soil erosion: | ||||||
| weak | 0,05 | |||||
| average | 0,10 | |||||
| strong | 0,15 | |||||
| very strong | 0,20 |
By comparing income with expenses, they find total balance and him intensity. For example, the nitrogen income per 1 ha is 115 kg, and the consumption is 90 kg, i.e. the total balance will be + 25 kg/ha (115–90), and the intensity of the balance will be 127% [(115:90) ∙ 100].
The overall balance of the main nutrients (nitrogen, phosphorus, potassium) is considered to be satisfactory when its intensity is approximately equal: for nitrogen - 110-120%, for phosphorus - 130-150, for potassium - 120-150%. According to the Institute of Soil Science and Agrochemistry, such values of the balance intensity in production conditions ensure the productivity of arable land at the level of 50–60 c/ha.
The optimal values of nitrogen balance intensity depending on the productivity of arable land are given in Table. 14.13.
14.13.Optimal intensity of nitrogen balance depending on productivity
Based on the results of long-term stationary field experiments, the Institute of Agrochemistry and Soil Science recommends optimal parameters the intensity of the balance of phosphorus and potassium depending on their content in soils (Table 14.14). According to the Institute of Soil Science and Agrochemistry and others scientific institutions, phosphorus is practically not washed out of the soil and does not pollute groundwater. Therefore, when calculating the balance, phosphate losses are not taken into account.
14.14. Optimal balance intensity depending on soil availability
phosphorus and potassium
Along with the total, it is also calculated effective balance, which characterizes the relationship between the removal of nutrients by plants and their possible assimilation from those entering the soil. By applying the coefficients of use of nutrients from fertilizers, the values of their possible absorption are found. By comparing the values of possible absorption of nutrients with the removal of crops, we obtain a characteristic of the effective balance.
Example. For 1 hectare of crop rotation area, 56 kg of nitrogen with mineral fertilizers was applied, 9 kg were added with precipitation, a total of 65 kg, of which 60% will be absorbed, i.e. 39 kg. Organic fertilizers will supply 70 kg of nitrogen and another 20 kg of biological (5 kg of symbiotic and 15 kg of non-symbiotic), a total of 90 kg/ha of nitrogen. In the first year, 25% of organic and biological nitrogen will be absorbed, or 22.5 kg (90 ∙ 0.25), together with mineral forms - 61.5 kg (39 + 22.5). Plants use 101 kg of nitrogen to create a crop. The effective balance is characterized by a minus value: 61.5–101.0 = –39.5 (kg/ha). The intensity of the effective nitrogen balance will be equal to 60% (61.5:101 ∙ 100).
Effective balances for phosphorus and potassium are calculated similarly.
To evaluate the fertilizer application system based on its effective balance, the possible absorption of nitrogen, phosphorus and potassium from soil reserves is calculated. The fertilizer application system can be considered correctly developed if the deficiency of nutrients in an effective balance is compensated for by possible absorption from the soil.
Example. To determine the possible absorption of nutrients from soil reserves, the weighted average values of the content of humus, phosphorus and potassium in the soil according to crop rotation are preliminarily calculated. Let the soil contain 2% humus and 100 mg/kg of soil phosphorus and potassium. According to the Institute of Soil Science and Agrochemistry, plants can absorb 20–25 kg of nitrogen from soil reserves for each percentage of humus in the soil. In our example, this will be 40–50 kg/ha of nitrogen. Plants absorb phosphorus at a level of 6–8% of the reserves of mobile forms in the soil, potassium – 10–15%. Their reserves in the soil are determined by multiplying the weighted average values of their content by a factor of 3. In our example, the reserves of phosphorus and potassium will be equal to 300 kg/ha (100 ∙ 3) of each element. Thus, 18–24 kg/ha of phosphorus (300 ∙ 0.06...0.08) and 30–45 kg/ha of potassium (300 ∙ 0.1...0.15) will be absorbed. If we take the effective balance of the previous example as 39.5 kg of nitrogen, that is, 40–50 kg of nitrogen can be absorbed from the soil, then the planned yields will be provided with nutrients and the fertilizer system can be considered correctly developed.
When assessing the fertilizer application system based on the balance of nutrients, a change in the content of mobile forms of phosphorus and exchangeable potassium in the soil during crop rotation is predicted. The intake of phosphorus and potassium during crop rotation in excess of consumption is divided by the standard (Tables 14.15, 14.16) and the increase in their content in the soil is determined. The result is summed up with the original content and a forecast is obtained.
14.15. Cost standards for phosphorus fertilizers in excess of removal from the harvest to increase
| Granulometric composition | pH KCl | ||||
| Less than 60 | 61–100 | 101–150 | 151–250 | ||
| Loamy | 4,5–5,0 | ||||
| 5,1–5,5 | |||||
| 5,6–6,0 | |||||
| Sandy loam | 4,5–5,0 | ||||
| 5,1–5,5 | |||||
| 5,6–6,0 | |||||
| Sandy | 4,5–5,0 | ||||
| 5,1–5,5 | |||||
| Peat | On average |
14.16. Cost standards for potassium fertilizers in excess of removal from the harvest to increase
| Granulometric composition | Balance intensity, % | Initial content of P 2 O 5, mg/kg of soil | ||
| Less than 80 | 81–140 | 141–200 | ||
| Loamy | ||||
| Sandy loam | ||||
| Sandy | ||||
| Peat | On average |
Example. Let us assume that annually 65 kg/ha of P 2 O 5 remains in the soil in excess of what is removed by the crop, i.e. for nine-field crop rotation, 585 kg/ha of P 2 O 5 will be received. In the first 4 years, the content of P 2 O 5 in the soil increases to 147 mg/kg with an initial content on loamy soil of 100 mg/kg and a replacement standard of 51 kg/ha per 10 mg/kg of soil (Table 14.16). In the next 5 years, the compensation standard increases to 65 kg/ha and the content of P 2 O 5 in the soil increases by another 50 mg/kg, reaching 200 mg/kg of soil by the end of the crop rotation. Thus, after nine years the content of P 2 O 5 in the soil should be 197 mg/kg. The K2O content is predicted similarly.
Calculation of calcium, magnesium and sulfur balance. IN credit side of the balance sheet the supply of these elements from lime, organic And mineral fertilizers, and also with precipitation And seeds, consumables– removal by harvest And losses from filtration and erosion. The intake of calcium and magnesium with lime fertilizers is calculated by the amount of lime fertilizers per 1 ha. For example, on average, 1.1 tons of dolomite flour, or 0.935 tons of CaCO 3 (CaCO 3 content - 85%) will be applied annually per 1 hectare of crop rotation area. From the table 14.17 we find the amount of CaO and MgO per 1 ha, applied with lime fertilizers. With 935 kg of CaCO 3 comes 280.5 kg of CaO (30 ∙ 9.35) and 187 kg of MgO (20 ∙ 9.35).
per 100 kg a.i. (N, P 2 O 5, K 2 O, CaCO 3), kg
| Fertilizers | SaO | MgO | S, % |
| Simple superphosphate | – | ||
| Double superphosphate | – | – | |
| Ammonium sulfate | – | – | 24,2 |
| Potassium sulfate | – | – | |
| Ground limestone | – | – | |
| Ground dolomite | – | ||
| Ground dolomitized limestone | 5,0 | – | |
| Chalk | – | – | |
| Slaked lime | – | – | |
| Dolomite flour | – | ||
| defect | – | – | |
| Cement dust | 1,0 | 1,0 | |
| Oil shale ash | – | ||
| Phosphogypsum (40% humidity, per 100 kg of physical mass) | – | 17,7–20,6 | |
| Potassium sulfate | 18,0 | ||
| Magnesium sulfate | 18,6 | ||
| Sodium sulfate | 22,6 |
According to the amount of mineral fertilizers per 1 hectare in d.v. determine the intake of CaO, MgO and S into the soil. For example, it is planned to apply 65 kg of P 2 O 5 in the form of double superphosphate per 1 hectare. With this amount of P 2 O 5 comes 20 kg of CaO (65 × 31/100). In the case of using ammonium sulfate and potassium sulfate, determine the amount of active substance supplied with these types of fertilizers per 1 ha, and calculate the sulfur intake using the data in table. 14.11.
Intake of calcium, magnesium and sulfur with organic fertilizers is calculated taking into account the saturation of the soil with the latter and the supply of these elements with fertilizers (see Table 14.11). For example, with a saturation of organic fertilizers in a crop rotation of 12 t/ha, the soil will receive 48 kg/ha CaO (4 × 12), 13.2 kg/ha MgO (1.1 × 12) and about 2.4 kg/ha SO 4 (0.2×12). With precipitation, 25.3 kg/ha of CaO, 3.6 of MgO, and 3.6 kg/ha of S enter the soil; with seeds, 0.3, respectively; 0.1 and 0.2 kg/ha. Summing up the results for the items of the income part of the balance, we obtain the supply of calcium, magnesium and sulfur per 1 hectare of crop rotation area.
Removal of calcium, magnesium and sulfur by the harvest are calculated in the same way as is done for nitrogen, phosphorus and calcium. Using the data given in table. 2.5, calculate the removal rates for each crop and calculate the average values per 1 ha. Losses from leaching and erosion are found from table. 14.12.
When liming, calcium loss due to leaching increases, especially on light soils. According to the Institute of Soil Science and Agrochemistry, on soils with a pH (KC1) of more than 6, calcium loss increases by an average of 40% compared to the average data on soils without liming. On acidic soils (pH less than 5), calcium leaching is approximately 20% lower. Therefore, when calculating the calcium balance, the average standard loss indicator (Table 14.12) on soils with a pH of more than 6 should be multiplied by 1.4, and on soils with a pH of less than 5 by 0.8.
The effect of liming on the leaching of magnesium is ambiguous, since in some cases calcium cations accelerate its leaching from the soil, which is due to the displacement of magnesium from the absorbing complex, and in others they can reduce the leaching of magnesium by neutralizing the acidity of the soil, which contributes to the loss of magnesium due to leaching. In this regard, when calculating the magnesium balance, the standards for losses from leaching given in table are used. 14.12. Determine the consumption per 1 ha.
By comparing the income and expense indicators, the balance values and its intensity are found.
QUESTIONS FOR SELF-CONTROL
1. What is meant by the balance of nutrients in the soil?
2. What is the importance of the balance of nutrients in the soil for regulating soil fertility and crop yields?
3. How to evaluate the system of using fertilizers in crop rotation based on the balance of nutrients?
4. What are the different types of battery balance?
5. How can we predict changes in soil fertility based on the balance of nutrients in it?
12/05/2016 APK News 791
December 5 is World Soil Day. Today, leading experts in the field of medicine and agriculture pay attention to the relationship between soil cultivation systems and the nutritional value of products. A negative balance of substances in the soil leads to a decrease in the most important essential substances in products (vitamins, minerals, micronucleiants, etc.). The cost of the imbalance, according to the World Health Organization, can amount to millions of lost years of life.
Institute of Organic Agriculture provides excerpts from the report WHO “Nutrition and health in Europe: a new framework for action” (2011):
"Despite the apparent diversity food products In supermarkets, the nutritional diet can be monotonous: “a variety of brands of food products does not mean their chemical diversity.
...Research on nutrition and health shows that a more varied diet is associated with reduced mortality from all causes and from cancer and cardiovascular disease. DALYs include an estimate of the number of years of life lost due to various diseases and the number of years lived with disability. 136 million years were lost in 2000 healthy life; the most important dietary risk factors caused the loss of more than 56 million, A another 52 million lost other factors related to food. Cardiovascular diseases (CVDs) and cancer account for approximately two thirds of the total burden of disease in Europe. According to conservative estimates, about one third of CVDs are associated with poor diet, although the need for more research is widely recognized. Cancer kills around one million adults every year in the WHO European Region. As in the case of CVD, approximately one third of all cancer deaths worldwide are caused by poor diet».
Poor diet is only one of the nutritional factors influencing mortality. Unfortunately, its assessment has been little studied, as noted in
Further, the WHO report talks about the relationship between the nutritional balance of the soil and the nutritional value of the diet: “It has long been known that great value in crop production has soil fertility. In an effort to maximize the use of land for growing crops, many farmers have abandoned the practice of leaving fields fallow for one season to allow the fields to naturally regain some of their fertility. Arable land can often be used to produce two harvests per year. Crop rotations that promote maximum fertility (for example, rotating a nitrogen-fixing crop with a crop that depletes soil nitrogen) have given way to replacing soil nitrogen through the application of nitrogen-rich fertilizers.
In addition, the desire to increase meat and dairy productivity has led to an increase in the use of fertilizers that promote the growth of specially bred fast-growing grasses in pastures, rather than maintaining traditional multi-grass meadows.
Systematic studies of how the lack of replenishment of microelements in the soil affects the nutrient content of crop yields have not been carried out. It can be argued that, at least in some areas, sufficient amounts of microelements remain in the soil to provide them high content in plants, and therefore in human food.
However, shortages can be found in some areas and appropriate measures are being taken. For example, adding iodine to irrigation water in one season resulted in a fivefold increase in iodine levels in local crops, vegetables and meat over the next three years, and this resulted in a reduction in infant mortality and stillbirths.”
According to Ministry of Agriculture of the Russian Federation, developed in Russia negative balance of nutrients in the soil. Over the past 10 years it has amounted to 86.9 million tons of active ingredients.
WHO nutritional data: “There is evidence that in the UK there has been a significant decline in the amount of essential minerals in common crops over the past 50 years. When comparing the mineral composition of 20 types of fruits and vegetables analyzed in the 1930s and in the 1980s, it was found that the levels of calcium, magnesium, sodium and copper in vegetables and potassium, iron, magnesium and copper in fruits were significantly reduced.
There is growing evidence that various chemical compounds in plants, such as phenols and flavonoids, may play a role in nutrition and act as protective factors against degenerative diseases. The influence of agricultural systems on these plant chemicals has been poorly studied.
Scientists at the University of Copenhagen have suggested that plants produce some of these compounds as a defense against pests and that using fertilizers in large quantities weakens these defense mechanisms, which in turn necessitates even greater use of pesticides to protect crops.
The research results also have implications for the trends observed in agriculture towards growing early maturing crops. The flavonoid and anthocyanin contents are reported to be several hundred percent higher in red onions harvested in July than in onions harvested in April.”
WHO data corresponds with the opinion of the Russian Institute of Organic Agriculture, repeatedly stating that modern system land use needs to be modernized, including the biologization of agriculture. “A simplified fertilization system based on compensation of only 3, albeit basic, nutrients (N, P, K) by applying only mineral fertilizers does not allow realizing the genetic potential of cultivated varieties and hybrids of agricultural crops,” they note. Institute of Organic Agriculture.
k.s-kh. n, h Head of the Department of Transfer of Innovative Technologies in the Agro-Industrial Complex of the Federal State Budgetary Educational Institution “Federal Center for Agricultural Consulting”, Chairman of the Scientific Council of the Institute of Organic Agriculture Amiran Zanilov:
“Soil fertility resources can ensure stable implementation of plant productivity, provided that a deficient balance of nutrients is maintained. When conducting agrochemical soil analysis, assessment general content macro and microelements are not carried out, which makes it impossible to include in the recommendations additional techniques for mobilizing difficultly soluble compounds. Research in this area should be intensified, and the existing system for calculating the need for batteries should be modernized. Today, unfortunately, 58 million hectares of Russian arable land are characterized by low humus content, and unsustainable land use continues .
For their vital functions, plants use carbon dioxide, water, a variety of organic compounds and mineral salts. Except traditional elements nitrogen, phosphorus and potassium, plants consume large amounts of other substances - calcium, magnesium, sulfur, silicon, iron. In smaller amounts, plants use molybdenum, boron, cobalt, copper, boron, zinc, etc. Each of the elements ensures the activity of biochemical processes that are characteristic only in the presence of a certain chemical element. Accordingly, it is unacceptable to ignore the importance of the essential elements accompanying nitrogen, phosphorus and potassium, as this will inevitably lead to disruption of plant growth and development.
A deficiency of one or another chemical element can cause a significant disruption in the formation of plants and the realization of its genetic potential. In accordance with the law of the minimum of the German chemist Justus von Liebig, in agriculture, an excess of one element does not replace the deficiency of others. A substance found in a minimum determines the state of the body. With a negative balance, the nutrient content in the soil will gradually decrease and plant yields will decrease.
The search for new means and methods for increasing the efficiency of the mineral fertilizers used, including new types of fertilizers based on organic and microbiological components, alternative sources of plant nutrition, and agricultural techniques can modernize the conservative system that has been practiced for many decades. At rational use mineral and organic fertilizers have a positive effect on the agrochemical parameters of the soil, increasing fertility indicators and, accordingly, increasing the nutritional value of agricultural products.
The combined use of organic and mineral fertilizers is recommended. Their combination makes it possible to avoid increased concentrations of soil solution when applying even higher doses of mineral fertilizers, which makes it possible to uninterruptedly supply plants with nutrients throughout the growing season and form a high yield. It is also necessary to use scientifically based crop rotations, use green manure crops, enrich the soil with beneficial bacteria, use perennial grasses and other biologization techniques and technologies. All this will allow us to obtain complete, environmentally friendly, healthy food products.”
Anna Lyubovedskaya
Director of External Relations
Institute of Organic Agriculture
Balance indicators reflect the paths of transformation and consumption of nutrients from mineral and organic fertilizers, the proportion of nutrients productively used and alienated by plants from the soil and reproduced through organic and mineral fertilizers. The balance of nutrients in the soil-plant-fertilizer system is part of the overall process of interaction of nutrients and belongs to the small biological cycle. The balance is calculated by comparing the amount of nutrients entering the soil with their consumption for creating a crop and unproductive losses.
Taking into account the results of the balance allows you to plan the production of agricultural products with the lowest costs and higher payback on organic and mineral fertilizers, predict the need for fertilizers and changes in the supply of soil nutrients, regulate soil fertility, protection environment. Calculations of the nutrient balance for individual farms and crop rotations make it possible to establish more reasonable crop fertilizer systems and reduce nutrient losses.
To assess the efficiency of agricultural production in large regions, regions, districts, farms, various types balance of nutrients in agriculture: biological, economic, differentiated and effective.
Biological balance gives the most complete picture of the cycle of substances. Incoming items of the biological balance include the supply of nutrients with organic and mineral fertilizers, sediments, seeds, symbiotic and non-symbiotic nitrogen fixation, while expenditure items include the content of nutrients in the main and by-products alienated from the field, in root and post-harvest residues.
The economic balance is determined by the gross receipt and alienation of batteries. When calculating the economic balance, all income and expense items are taken into account, including unproductive losses. The economic balance characterizes not only the share of participation of fertilizers in the small biological cycle, the provision of crops with nutrients, but also the nature of changes in their content in the soil, which makes it possible to quantitatively predict trends in changes in soil fertility. At the same time, the economic balance does not give a complete picture of the nutritional conditions of individual crops or crop rotation as a whole, since plants use only part of the nutrients from the applied fertilizers.
Differentiated balance. When calculating this type of balance, the amount of mineral fertilizers does not apply to the entire area of land, but only to the area of their primary application, i.e. on soils insufficiently supplied with nutrients.
The effective balance is determined taking into account the possible utilization rates of nutrients from fertilizers in the year of their application or during crop rotation.
The balance of nutrients is assessed by indicators of nutrient deficiency or excess, intensity, structure, capacity, and reutilization of nutrients.
A deficiency or excess of nutrients represents the difference between all sources of their supply and consumption and is expressed in absolute (kg, tons) or relative (%) values for the entire area or unit area.
Balance intensity is the ratio of the supply of nutrients to their removal by the crop. Expressed as percentages or ratios. A balance intensity value of less than 100% characterizes a deficit balance, and more than 100% characterizes a positive balance.
Balance capacity is the sum of removal from the soil and all items of replacement of nutrients. It characterizes the power of the circulation of substances. The greater the balance capacity, the more intensive the farming in the region, region, or farm under study.
Balance sheet structure – characterizes the share of individual items of income and consumption of batteries. Analysis of the balance sheet structure allows you to evaluate the sources of income and the costs of producing a unit of product.
Nutrient recycling is defined as the ratio of nutrients entering the soil with manure to their removal by crops, i.e. reutilization characterizes the reuse of nutrients received with mineral fertilizers through crop products (straw, animal feed) that have passed through livestock farms and returned to the field in the form of manure.
The degree of recycling of nutrients is determined mainly by the specialization of the farm and the concentration of livestock. High reuse of nutrients occurs on livestock farms, where the marketability of crop products is lower. If peat manure composts, rather than manure, are used as organic fertilizers, then when determining the degree of reutilization, it is necessary to subtract their presence in the peat used to prepare composts from the total amount of nutrients added to the soil with organic fertilizers.
The balance of nitrogen, phosphorus and potassium in agriculture of the Republic of Belarus, calculated for the period from 1966 to 1998, fairly objectively reflects the nature of the use of mineral and organic fertilizers (Tables 8.36 - 8.38).
In 1986-1990 the application of nitrogen fertilizers on the republic's arable land was 88 kg/ha a.i., which, together with nitrogen in organic fertilizers, ensured a positive nitrogen balance of 23.8 kg/ha, and an intensity of 118%. The minimum use of nitrogen fertilizers, as well as phosphorus and potassium fertilizers, was noted in 1995. The nitrogen balance that year was 9.2 kg/ha, which indicates its insufficiency for shaping the yield of cultivated crops. Subsequently, the intensity of the nitrogen balance was maintained at 100%, but its supply with mineral fertilizers was 51-55 kg/ha a.i. was below the required requirement.
The phosphorus balance on arable land for the period after 1986 decreased from 58-59 kg/ha a.i. up to 12-17 kg/ha a.i. in 1997-1998 Almost since 1994, the supply of phosphorus with mineral fertilizers has not compensated for its removal from the harvest. Application of phosphorus fertilizers at the level of 20-23 kg/ha a.i. is not enough to obtain high and stable crop yields and maintain the achieved P2O5 content in soils.
The use of potash fertilizers over the past 15 years has been more stable, but in 1993-1996. it provided only a weakly positive balance (6.0-24.5 kg/ha) and was insufficient to maintain soil fertility.
To ensure effective use fertilizers, it is recommended to maintain the intensity of the balance of nitrogen at the level of 100 - 110, phosphorus - 130-150, potassium - 140-160% with the content of P2O5 and K2O in soils within the range of 140-200 mg/ha.
Nutrient balance is an essential part of the fertilization system. Its calculation is carried out to determine the possible enrichment or depletion of the soil with certain nutrients.
Incoming balance items are: their application with organic and mineral fertilizers, the supply of nutrients due to biological accumulation caused by the absorption of nutrients from deep horizons, the supply of nitrogen due to the fixation of nitrogen from the air and with precipitation.
The consumption of nutrients from the soil is determined by the following items: removal with the crop, the transition of nutrient compounds into a sparingly soluble state, gaseous losses of nitrogen and leaching of soluble compounds of nitrogen and potassium from the root layer, losses as a result of soil erosion.
Table 12. Removal of basic nutrients by harvest
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Culture |
Planned yield, c/ha |
Removal per 1 c of main products, taking into account by-products, kg |
Removal by planned harvest, kg/ha |
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Pure steam |
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Winter wheat |
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Potato |
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Vika/oats |
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Spring wheat |
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On average from 1 ha |
Winter wheat removes the most nitrogen from the harvest. Winter wheat takes out the most phosphorus with the planned harvest, this is explained by the high yield of winter wheat, and potassium from potatoes, since it is a potassium-loving crop. On average, the offset is small because The planned yield of most crops is not high.
Table 13. Approximate balance of nutrients in crop rotation
- 1. We take the removal of nutrients from table 12.
- 2. Supply of nutrients to the soil, total:
N=110.3 kg/ha; P 2 O 5 =183.5 kg/ha; K 2 O = 76.7 kg/ha;
a) the supply of organic fertilizers is calculated as follows:
N = 100/6 = 16.6 kg/ha; P 2 O 5 = 50/6 = 8.3 kg/ha; K 2 O = 120/6 = 20 kg/ha.
b) we take receipts from mineral fertilizers from table 8
N = 91.1 kg/ha; P 2 O 5 = 100.5 kg/ha; K 2 O = 56.7 kg/ha.
- c) The arrival of N2 in the soil due to nitrogen fixation (we keep records on vetch/oats):
- 64/4 = 16 kg/ha;
- 16/6 = 2.6 kg/ha.
- 3. Nutrient balance:
N= 110.3 -103.75 = 6.6 kg/ha;
P 2 O 5 = 183.5 - 38.8 = 144.7 kg/ha;
K 2 O = 76.7 - 105.8 = - 29.1 kg/ha.
4.% to takeaway:
N = 6.6*100/103.75 = 6.4%;
P 2 O 5 = 144*100/38.8 = 373%;
K 2 O = -29.1*100/105.8 = - 27.5%.
The crop rotation soil is close to class 5 in terms of potassium supply, class 3 in terms of phosphorus supply and class 4 in nitrogen supply. The nutrient balance for nitrogen and potassium is negative. This means that it is necessary to apply an increased dose of nitrogen and potassium fertilizers so that the nutrient balance becomes positive and maintained.