Of the indirect methods for determining humus, the method of I.V. Tyurin, based on the oxidation of carbon of the organic matter of the soil with a sulfate solution of potassium dichromate, the excess of which is titrated with a solution of Mohr's salt, is most widely used. In fact, this method determines the oxidizability of humus. If we assume that the interaction of a solution of potassium dichromate with soil only oxidizes the carbon of humus and restores Cr 2 O 7 2- to Cr 3+, then the reaction can be schematically expressed by the following equation:
3С + 2K 2 Cr 2 O 7 + 8H 2 SO 4 → 3CO 2 + 2Cr 2 (SO 4) 3 + 2K 2 SO 4 + 8H 2 O
Since the potassium dichromate solution is poured into the sample of soil in excess, some part of it remains unused after the completion of the carbon oxidation reaction. The unreacted excess of Cr 2 O 7 2- is titrated with Mohr's salt solution (NH 4) 2 SO 4 ∙ FeSO 4 ∙ 6H 2 O:
K 2 Cr 2 O 7 + 6FeSO 4 + 7H 2 SO 4 → Cr 2 (SO 4) 3 + 3Fe 2 (SO 4) 3 + K 2 SO 4 + 7H 2 O
The volume of Mohr's salt solution used for titration is used to calculate the carbon content of the soil.
When interacting with humus, the Cr 2 O 7 2- ion reacts not only with carbon, but also with hydrogen, which is part of organic compounds:
12Н + 2K 2 Cr 2 O 7 + 8H 2 SO 4 → 2Cr 2 (SO 4) 3 + 2K 2 SO 4 + 14H 2 O
Since the product of hydrogen oxidation is water, it will not affect the results of carbon determination only if the ratio of hydrogen and oxygen atoms in the composition of soil humus is 2:1, as in H 2 O. If the ratio H:O >2 in humus, then more K 2 Cr 2 O 7 is consumed for its oxidation than is required for carbon oxidation, and the results are overestimated. With a ratio of H:O< 2 на окисление гумуса K 2 Cr 2 O 7 израсходуется меньше, чем необходимо для окисления углерода. В этом случае результаты будут заниженными.
Sulfuric acid solution of potassium dichromate reacts not only with humus, but also with some mineral components of the soil.
When analyzing soils containing free carbonates, sulfuric acid is partially neutralized, but this does not affect the results of determining humus carbon.
If the soils are saline and contain chloride ions, then the results of determining the total humus turn out to be overestimated, because along with the oxidation of carbon, Cr 2 O 7 2- is also consumed for the oxidation of chloride ions. The presence of reduced iron and manganese ions in hydromorphic soils also leads to overestimated results, since a part of Cr 2 O 7 2- goes to the oxidation of these ions. However, restrictions on the use of the Tyurin method for determining the humus content in hydromorphic soils apply only to freshly taken samples. It has been repeatedly noted in the literature that when analyzing samples of hydromorphic soils dried to an air-dry state, the results of determining humus obtained by the Tyurin method practically do not differ from the results obtained by the Knopp-Sabanin method. Therefore, the Tyurin method can also be used for the analysis of air-dry samples of hydromorphic soils.
The shortcomings of the Tyurin method include incomplete oxidation of organic matter, especially when analyzing samples from peaty horizons or enriched in decomposed plant remains. The humus content found by the Tyurin method is 85-95% of the amount determined by the dry combustion method according to Gustavson. For a more complete oxidation of carbon in organic compounds with a solution of potassium dichromate, I.V. Tyurin recommended using 0.1-0.2 g of Ag 2 SO 4 as a catalyst. In this case, 95–97% of the carbon of organic compounds is oxidized; however, in the practice of mass analyzes, a catalyst is usually not used.
Analysis progress. On an analytical (or torsion) balance, a sample of soil prepared for determining the total humus is taken, accurate to the third decimal place. It is recommended to adhere to the following weights (V.V. Ponomareva, T.A. Plotnikova, 1980):
Samples of soils are transferred into dry, clean 100 ml conical flasks and exactly 10 ml of a 0.4 N solution of a chromium mixture are added to them from a burette. It is a thick, viscous liquid, and if it is added quickly, some of the reagent will remain on the walls of the burette, which will lead to a large inaccuracy in the results of the analysis. The chromium mixture must be added slowly, at such a speed that falling drops can be seen. The nose of the burette should touch the neck of the flask to avoid splashing of the reagent when the drops fall freely.
The flasks are closed with small funnels or a stopper - a refrigerator and placed on a preheated tile. From the moment large bubbles of gas appear, the solution should boil moderately for exactly 5 minutes. It should not be taken as the beginning of boiling the intense release of small bubbles of air absorbed by the soil, which occurs even before boiling. The boil should always be more or less the same in intensity, neither too violent nor too weak, and the bubbles a little larger than a poppy seed. Boiling should not be accompanied by the release of steam from the funnel.
In the process of boiling, the solution of the chromium mixture changes its color from reddish-brown to brownish-brown, and sometimes green. The green color of the chromium mixture after boiling indicates that potassium dichromate was not enough to completely oxidize the soil humus. In this case, the analysis should be repeated with a smaller sample of soil.
After the boiling time, the flasks are removed from the stove and cooled. The funnel or stopper-refrigerator, as well as the walls of the flask, are washed from the rinse with distilled water, diluting the solution in the flask by 2-3 times. Add 5-6 drops of an indicator (0.2% solution of phenylanthranilic acid) and titrate the unreacted residue of the chromium mixture with 0.2 N. Mohr's salt solution until the brownish-brown color changes first to purple and then to green. The color of the chromium mixture, especially at the end of the titration, changes very sharply, so the titration must be done carefully and vigorously stir the contents of the flask all the time in a circular motion. The transition from purple to green comes from one drop of Mohr's salt. Reliable results are obtained when at least 10 ml of 0.2 N Mohr's salt solution is used to titrate the potassium dichromate residue.
Under strictly similar conditions, a blank determination is carried out in 2-fold repetition, adding about 0.1 g of calcined soil or pumice to the flask instead of the analyzed soil.
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where V 1 is the amount of Mohr's salt solution used for titration of 10 ml of chromium mixture in a blank experiment, ml; V 2 - the amount of Mohr's salt solution used for titration of the chromium mixture of the analyzed sample, ml; n is the normality of the Mohr salt; 0.003 – molar mass of carbon equivalent, g/mol; m is the sample of soil, g; Kn 2 o - conversion factor for absolutely dry soil; 100 is a multiplier for conversion to 100 g of soil.
Calculation example. The sample of soil taken to determine humus is 0.305 g. 25.8 ml of Mohr's salt solution was used for titration of a blank sample, 22.3 ml of Mohr's salt solution was used for titration of the analyzed sample. The normality of Mohr's salt solution is 0.204. The conversion factor for absolutely dry soil is 1.072. The organic carbon content is:
Humus \u003d 0.96 ∙ 1.724 \u003d 1.66%.
The following reagents are used for analysis:
1. 0.4 n. solution of K 2 Cr 2 O 7 in dilute (1:1) sulfuric acid. 40 g of K 2 Cr 2 O 7 are dissolved in 500-600 ml of distilled water and filtered through a paper filter into a 1-liter volumetric flask. The solution is brought to the mark with distilled water and poured into a heat-resistant container with a capacity of 2.5-5 liters. To a solution of K 2 Cr 2 O 7 in a fume hood, poured in small portions (approximately 100 ml each) with careful and repeated stirring, 1 liter of concentrated H 2 SO 4 (pl. 1.84). When the solution is mixed with sulfuric acid, a strong heating of the liquid occurs, so you need to perform operations very carefully and use only heat-resistant dishes.
The prepared solution is closed with a funnel or glass and left to stand for complete cooling until the next day, then poured into a bottle with a ground stopper and stored in a dark place.
2. 0.2 n. Mohr's salt solution. Take 80 g of salt (NH 4) 2 SO 4 ∙ FeSO 4 ∙ 6H 2 O ( only blue crystals are used, brown ones are discarded) is placed in a flask filled with 650-700 ml of 1 N H 2 SO 4 solution and the solution is shaken until the salt is completely dissolved. The solution was then filtered into a 1 L volumetric flask and made up to the mark with distilled water. Mohr's salt solution is stored in a bottle insulated from the air with a Tishchenko flask with an alkaline solution of pyrogallol or a tube with Mohr's salt crystals.
The normality of Mohr's salt solution is established and checked by 0.1 N. KMnO 4 solution. Due to the fact that the normality of Mohr's salt changes rapidly, it should be checked after 1-2 days. To do this, 1 ml of H 2 SO 4 (density 1.84) is poured into a 250 ml conical flask with a measuring cylinder, 10 ml of Mohr's salt solution is measured with a burette, 50 ml of distilled water is added and titrated with 0.1 N. KMnO 4 solution (prepared from fixonal) to a slightly pink color that does not disappear within 1 min. The titration is repeated and the average value is taken. The normality of a solution of Mohr's salt is found by the formula:
V 1 ∙ N 1 = V 2 ∙ N 2
where V 1 and N 1 are the volume and normality of the Mohr salt solution, V 2 and N 2 are the volume and normality of the KMnO 4 solution.
3. 0.2% solution of phenylanthranilic acid C 13 H 11 O 2 N. Phenylatranilic acid is insoluble in water, so the indicator is prepared in a soda solution, for which 0.2 g of phenylanthranilic acid is dissolved in 100 ml of a 0.2% solution of anhydrous soda ( Na 2 CO 3). For better dissolution, a portion of phenylanthranilic acid is preliminarily moistened in a porcelain cup with a 0.2% soda solution to a creamy state and, in this form, is thoroughly mixed with a glass rod. After that, the rest of the soda solution is poured.
4. 1 n. H 2 SO 4 solution. In a 1 L volumetric flask filled with ~ 500 ml of distilled water, add 28 ml of concentrated H 2 SO 4 measured with a cylinder and mix. Allow the flask to cool to room temperature, dilute to the mark with distilled water and mix thoroughly.
Humus comes from lat. humus"earth, soil" - the main organic matter of the soil, containing the nutrients necessary for higher plants. Humus makes up 85-90% of soil organic matter and is an important criterion in assessing soil fertility. In the weight composition of the upper soil layer, the humus content varies from a fraction of a percent for steppe soils to 10-15% for chernozems. Humus consists of individual (including specific) organic compounds, products of their interaction, as well as organic compounds in the form of organo-mineral formations.
Humus is formed in the soil as a result of the transformation of plant and animal organic residues - humification.
To determine the content of organic matter in the soil, in soil analysis laboratories determine separately the amount of plant residues and humus. Plant residues are isolated from the soil in a dry or wet way, after which their amount is determined. To determine the amount of humus at soil chemical analysis it is necessary to determine the carbon content of decomposed organic matter in the soil - organic carbon. To determine organic carbon in soil analysis laboratories using the oxidometric method of analysis. Samples for soil chemical analysis for humus content are selected in accordance with GOST 17.4.3.01-83 “Nature protection. Soils. General requirements for sampling" .
The essence of the oxidometric method for determining humus in the soil lies in the fact that organic matter is oxidized with potassium dichromate in a strongly acidic medium until carbon dioxide is formed, then the excess of potassium dichromate is titrated with a solution of Mohr's salt and the content of organic carbon in the soil is determined by the difference in the volumes of Mohr's salt used for titration of dichromate potassium in the experiment without soil and in the experiment with soil. The soil weight is taken depending on the approximate humus content: 0.05-1 gram for chernozems, about 1 gram for light gray soils.
Basic terms and definitions according to GOST: 27593-88 Soils. Terms and Definitions.
Humic acids- a class of high-molecular organic nitrogen-containing hydroxy acids with a benzoic nucleus, which are part of humus and are formed in the process of humification.
Humic acids(HA) - a group of dark-colored humic acids, soluble in alkalis and insoluble in acids.
Hymatomelanic acids(HMC) is a group of humic acids soluble in ethanol. Fulvic acids(FC)- a group of humic acids, soluble in water, alkalis and acids.
Gumin- organic matter that is part of the soil, insoluble in acids, alkalis, organic solvents.
Degree of humification of organic matter is the ratio of the amount of carbon in humic acids to the total amount of soil organic carbon, expressed in mass fractions.
Method I.V. Tyurin is based on the oxidation of soil organic matter with chromic acid to the formation of carbon dioxide. The amount of oxygen consumed for the oxidation of organic carbon is determined by the difference between the amount of chromic acid taken for oxidation and the amount of it remaining unused after oxidation. As an oxidizing agent, 0.4 N. solution of K2Cr2O7 in sulfuric acid, previously diluted with water in a ratio of 1:1.
The oxidation reaction proceeds according to the following equations:
- 1) 2K 2 Cr 2 O 7 + 8H 2 SO 4 \u003d 2K 2 SO 4 + 2Cr 2 (SO4) 3 + 8H 2 O + 3O 2
- 2) 3C + 3O 2 \u003d 3CO 2
The rest of the chromic acid not consumed for oxidation is titrated with 0.1 N. Mohr's salt solution with indicator diphenylamine. Titration with Mohr's salt, which is a double salt of ammonium sulphate and ferrous sulphate - (NH4) 2SO4. FeSO4.GH2O, follows the following equation:
K 2 Cr 2 O 7 + 7H 2 SO 4 + 6FeSO 4 \u003d 7H 2 O + K 2 SO 4 + Cr 2 (SO4) 3 + 3Fe 2 (SO4) 3
The use of silver sulfate as a catalyst increases the completeness of oxidation to 95% (Komarov).
To get reliable results, you need to pay attention to:
- 1) careful preparation of the soil for analysis;
- 2) exact observance of the duration of boiling during the oxidation of organic matter; the boiling of the oxidizing mixture itself should proceed calmly.
Soil preparation for analysis. When preparing the soil for analysis for humus content, special attention should be paid to the removal of roots and various organic residues of plant and animal origin from the soil.
From a soil sample taken in the field and brought to an air-dry state, an average sample of 50 g is taken, the roots and organic residues visible to the eye (insect shells, seeds, coals, etc.) are carefully selected with tweezers, soil clods are crushed with a wooden pestle with a rubber with a tip and again carefully select the roots, using a magnifying glass.
Then the soil is ground in a porcelain mortar and passed through a sieve with a hole diameter of 1 mm, after which an average sample weighing 5 g is again taken from it and the selection of roots is repeated using the following method. A dry glass rod is vigorously rubbed with a dry cloth or woolen cloth and quickly passed at a height of about 10 cm above the soil, distributed in a thin layer over the surface of wax or parchment paper.
Thin small roots and semi-decomposed plant residues, which could not be selected before due to their small size, stick to the surface of the electrified stick and are thus removed from the soil. They are removed from the stick when it is rubbed again. It should not be held too low with a stick above the soil surface in order to avoid the removal of not only organic residues from the soil, but also fine earth.
In the process of selecting roots, it is necessary to repeatedly mix the soil and again distribute it in a thin layer. The operation should be carried out until only single roots are found on the stick. The purity of the selection of roots is controlled, in addition, by viewing the soil in a magnifying glass.
At the end of the selection of roots, the soil is again ground in a porcelain, jasper or agate mortar and passed through a sieve with a hole diameter of 0.25 mm. The entire 5g sample should be prepared in the manner described above. It is impossible to discard a part of the sample that is difficult to grind.
The soil prepared in the above way for analysis should be stored in parchment paper or wax bags or in test tubes with stoppers.
GOST 27593-88
UDC 001.4:502.3:631.6.02:004.354
Group C00
INTERSTATE STANDARD
Terms and Definitions
soils. Terms and definitions
ISS 01.040.13
Date of introduction 01.07.88
INFORMATION DATA
1. DEVELOPED AND INTRODUCED by the State Agro-Industrial Committee of the USSR
2. APPROVED AND INTRODUCED BY Decree of the USSR State Committee for Standards dated February 23, 1988 No. 326
3. The standard fully complies with ST SEV 5298-85
4. REPLACE GOST 17.4.1.03-84
5. REFERENCE REGULATIONS AND TECHNICAL DOCUMENTS
6. REPUBLICATION. November 2005
This International Standard establishes terms and definitions of concepts in the field of soil science.
The terms established by this standard are mandatory for use in all types of documentation and literature that are within the scope of standardization or use the results of this activity.
This standard should be used in conjunction with GOST 20432.
1. Standardized terms with definitions are given in Table. 1.
2. One standardized term is established for each concept.
The use of terms - synonyms of the standardized term is not allowed. Synonyms that are unacceptable for use are given in Table. 1 as reference and marked with "Ndp".
2.1. For individual standardized terms in Table. 1 are given as reference short forms that are allowed to be used in cases that exclude the possibility of their different interpretation.
2.2. The above definitions can be changed, if necessary, by introducing derivative features into them, revealing the meaning of the terms used in them, indicating the objects included in the scope of the concept being defined. Changes should not violate the scope and content of the concepts defined in this standard.
Table 1
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Definition |
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GENERAL CONCEPTS |
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1. Soil |
An independent natural-historical organo-mineral natural body that arose on the surface of the earth as a result of prolonged exposure to biotic, abiotic and anthropogenic factors, consisting of solid mineral and organic particles, water and air and having specific genetic and morphological features, properties that create appropriate conditions for the growth and development of plants |
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2. Soil classification |
The system of separation of soils by origin and (or) properties |
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3. Soil profile |
The set of genetically conjugated and regularly changing soil horizons into which the soil is divided in the process of soil formation |
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4. Soil horizon |
A specific layer of the soil profile formed as a result of the impact of soil-forming processes |
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5. Type of soil |
The main classification unit, characterized by a commonality of properties determined by the regimes and processes of soil formation, and a single system of main genetic horizons |
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6. Soil subtype |
Classification unit within a type, characterized by qualitative differences in the system of genetic horizons and in the manifestation of overlapping processes that characterize the transition to another type |
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7. Type of soil |
Classification unit within the subtype, determined by the characteristics of the composition of the soil-absorbing complex, the nature of the salt profile, the main forms of neoplasms |
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8. Type of soil |
Classification unit within a genus, quantitatively differing in the degree of expression of soil-forming processes that determine the type, subtype, and genus of soils |
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9. Variety of soil |
Classification unit that takes into account the division of soils according to the granulometric composition of the entire soil profile |
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10. Soil Discharge |
Classification unit grouping soils according to the nature of soil-forming and underlying rocks |
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11. Ground cover |
The totality of soils that cover the earth's surface |
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12. Structure of the soil cover |
Spatial arrangement of elementary soil areas that are genetically related to each other to varying degrees and create a certain spatial pattern |
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13. Soil-forming factors |
Elements of the natural environment: soil-forming rocks, climate, living and dead organisms, age and terrain, as well as anthropogenic activities that have a significant impact on soil formation |
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14. Elementary soil range |
Primary component of soil cover, which is the area covered by soil in one of the lowest ranking units |
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15. Soil mapping Ndp. Mapping |
Drawing up soil maps or maps of their individual properties |
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16. Soil fertility |
The ability of the soil to meet the needs of plants in nutrients, moisture and air, as well as to provide conditions for their normal life |
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17. Soil passport |
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18. Soil evaluation |
Comparative assessment in points of soil quality by natural properties |
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PHYSICAL PROPERTIES OF SOILS |
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19. Mechanical element of soil |
Isolated primary particles of rocks and minerals, as well as amorphous compounds in soil |
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20. Soil aggregate |
Structural unit of soil, consisting of soil mechanical elements connected to each other |
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21. Mechanical fraction of soil |
A set of mechanical elements, the size of which is within certain limits |
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22. Soil Skeleton |
The set of mechanical elements of the soil with a size of more than 1 mm |
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23. Fine earth |
The totality of mechanical soil elements less than 1 mm in size |
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24. Silty soil fraction |
The set of mechanical elements of the soil in size from 0.001 to 1.0 mm |
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25. Soil colloids |
The set of mechanical elements of the soil in size from 0.0001 to 0.001 mm |
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26. Granulometric composition of the soil |
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27. Solid part of the soil |
The totality of all types of particles that are in the soil in a solid state at a natural level of moisture |
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28. Soil structure |
The physical structure of the solid part and the pore space of the soil, due to the size, shape, quantitative ratio, the nature of the relationship and the location of both mechanical elements and aggregates consisting of them |
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29. Pore space in soil |
Gaps of various sizes and shapes between mechanical elements and soil aggregates occupied by air or water |
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30. Soil moisture |
Water in the soil and released by drying the soil at a temperature of 105 ° C to constant mass |
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31. Soil moisture capacity |
The value that quantitatively characterizes the water-holding capacity of the soil |
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32. Soil swelling |
Increase in the volume of the soil as a whole or individual structural elements when moistened |
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33. Soil consistency |
The degree of mobility of the particles that make up the soil under the influence of external mechanical influences at different soil moisture, due to the ratio of cohesive and adhesive forces |
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34. Soil density |
The ratio of the mass of dry soil taken without disturbing the natural composition to its volume |
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35. Soil air capacity |
Volume of pore space containing air at soil moisture corresponding to field capacity |
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36. Soil biological activity |
The totality of biological processes occurring in the soil |
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37. Biological accumulation in soil |
Accumulation in the soil of organic, organo-mineral and mineral substances as a result of the vital activity of plants, soil microflora and fauna |
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SOIL CHEMICAL COMPOSITION AND PROPERTIES |
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38. Chemical characteristics of the soil |
Qualitative and quantitative description of the chemical properties of the soil and the chemical processes occurring in it |
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39. Soil organic matter |
The totality of all organic substances in the form of humus and the remains of animals and plants |
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40. Humus |
Part of soil organic matter, represented by a combination of specific and non-specific organic substances of the soil, with the exception of compounds that are part of living organisms and their residues |
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41. Group composition of humus |
List and quantitative content of groups of organic substances that make up humus |
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42. Fractional composition of humus |
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43. Specific humic substances |
Dark-colored organic compounds that are part of humus and are formed in the process of humification of plant and animal residues in the soil |
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44. Humic acids |
A class of high-molecular organic nitrogen-containing hydroxy acids with a benzoic nucleus, which are part of humus and are formed in the process of humification |
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45. Humic acids |
A group of dark-colored humic acids, soluble in alkalis and insoluble in acids |
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46. Hymatomelanic acids |
Group of humic acids soluble in the standard |
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47. Fulvic acids |
A group of humic acids soluble in water, alkalis and acids |
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48. Gumin |
Organic matter that is part of the soil, insoluble in acids, alkalis, organic solvents |
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49. Organo-mineral compounds of the soil |
Complex, heteropolar, adsorption and other products of the interaction of organic and mineral substances of the soil |
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50. Degree of humification of organic matter |
The ratio of the amount of carbon in humic acids to the total amount of soil organic carbon, expressed in mass fractions |
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51. Mineralization of the soil solution |
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52. Easily soluble soil salts |
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53. Sparingly soluble soil salts |
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54. Mobility of chemical compounds in soil |
The ability of compounds of chemical elements to pass from the solid phases of the soil into the soil solution |
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55. Soil acidity |
The ability of the soil to exhibit the properties of acids |
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56. Soil alkalinity |
The ability of the soil to exhibit the properties of the bases |
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57. Soil buffering |
The ability of the soil to resist changes in its properties under the influence of various factors |
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58. Acid-base buffering of the soil |
The ability of the soil to withstand changes in the pH of the soil solution when the soil interacts with acids and bases |
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ION EXCHANGE PROPERTIES OF SOILS |
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59. Soil absorption complex |
The set of mineral, organic and organo-mineral particles of the solid phase of the soil, which have absorptive capacity |
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60. Ion exchange in soil |
Reversible reaction of stoichiometric exchange of ions between the solid and liquid phases of the soil |
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61. Selectivity of metabolism in soil |
The ability of the soil to preferential absorption of certain types of ions |
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62. Soil cation exchange capacity |
The maximum amount of cations that can be retained by the soil in the exchange state under given conditions |
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63. Soil anion exchange capacity |
The maximum amount of anions that can be retained by the soil in the exchange state under given conditions |
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64. The amount of exchangeable cations in the soil |
The total amount of exchangeable cations in the soil. |
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Note. Exchangeable cations include: potassium, sodium, calcium, magnesium, etc. |
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65. Exchange bases of soil |
Exchangeable cations that are part of the soil absorbing complex |
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66. Sum of exchangeable bases in soil |
The total number of exchangeable bases in the soil |
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67. The degree of saturation of the soil with bases |
The ratio of the sum of exchangeable bases to the sum of hydrolytic acidity and the sum of exchangeable bases |
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SOIL ANALYSIS |
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68. Soil analysis |
A set of operations performed to determine the composition, physical-mechanical, physical-chemical, chemical, agrochemical and biological properties of the soil |
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69. Soil test site |
Representative part of the study area, intended for sampling and detailed study of the soil |
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70. Single soil sample |
A sample of a certain volume, taken once from a soil horizon, layer |
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71. Pooled soil sample Ndp. Mixed soil sample |
Soil sample consisting of a given number of single samples |
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72. Absolutely dry soil sample |
Soil sample dried to constant weight at 105°C |
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73. Air dry soil test |
Soil sample dried to constant weight at laboratory temperature and humidity |
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74. Soil extract |
An extract obtained after soil treatment with a solution of a given composition, which acted on the soil for a certain time at a certain soil-solution ratio |
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SOIL PROTECTION AND MANAGEMENT |
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75. Soil protection |
A system of measures aimed at preventing the decline in soil fertility, their irrational use and pollution |
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76. Soil management |
Economically, ecologically and socially justified use of soils in the national economy |
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77. Soil degradation |
Deterioration of soil properties and fertility as a result of natural or anthropogenic factors |
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78. Soil erosion |
Destruction and demolition of the upper most fertile soil horizons as a result of the action of water and wind |
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79. Depletion of the soil |
Depletion of nutrients and a decrease in the biological activity of the soil as a result of its irrational use |
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80. Soil fatigue |
The phenomenon observed in the monoculture of plants and is expressed in a decrease in yield with the introduction of full fertilizer and the preservation of favorable physical and mechanical properties of the soil |
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81. Soil leaching |
Washing out of the soil of various substances by filtering solutions |
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82. Soil salinization |
Accumulation of easily soluble salts in the soil |
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83. Migration of chemical compounds |
Movement of chemical compounds within a soil horizon, profile, or landscape |
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84. Hummification |
According to GOST 20432 |
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85. Soil acidification Ndp. soil acidification |
Changes in the acid-base properties of the soil caused by the natural soil-forming process, the entry of pollutants, the introduction of physiologically acidic fertilizers and other types of anthropogenic impact |
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86. Soil alkalization Ndp. Soil alkalization |
Changes in the acid-base properties of the soil caused by the natural soil-forming process, the entry of pollutants, the introduction of physiologically alkaline ameliorants and other types of anthropogenic impact |
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87. Soil pollution |
Accumulation of substances and organisms in the soil as a result of anthropogenic activity in such quantities that reduce the technological, nutritional and hygienic and sanitary value of cultivated crops and the quality of other natural objects |
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88. Global soil pollution |
Soil pollution resulting from the long-range transport of a pollutant in the atmosphere over distances exceeding 1000 km from any source of pollution |
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89. Regional soil pollution |
Soil pollution resulting from the transfer of a pollutant into the atmosphere at distances of more than 40 km from technogenic and more than 10 km from agricultural sources of pollution |
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90. Local soil pollution |
Soil pollution near one or a combination of several sources of pollution |
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91. Background content of a substance in soil |
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92. Industrial source of soil pollution |
Source of soil pollution caused by the activities of industrial and energy enterprises |
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93. Transport source of soil pollution |
Source of soil pollution due to the operation of vehicles |
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94. Agricultural source of soil pollution |
Source of soil pollution due to agricultural production |
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95. Household source of soil pollution |
Source of soil pollution caused by human household activities |
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|
96. Soil pollution control |
Checking the conformity of soil pollution in accordance with established norms and requirements |
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|
97. Soil pollution monitoring |
System of regulatory observations, including observations of actual levels, determination of predictive levels of pollution, identification of sources of soil pollution |
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|
98. Soil pollutant |
A substance that accumulates in the soil as a result of anthropogenic activities in such quantities that adversely affect the properties and fertility of the soil, the quality of agricultural products |
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|
99. Pesticide residue in soil |
Amount of pesticide after a specified waiting period from the moment of its application |
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|
100. Soil self-purification |
The ability of soil to reduce the concentration of a pollutant as a result of migration processes occurring in the soil |
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|
101. Soil self-purification time |
The time interval during which the mass fraction of a soil pollutant decreases by 96% of the initial value or its background content |
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|
102. Maximum allowable concentration of a soil pollutant |
The maximum concentration of a soil pollutant that does not cause a negative direct or indirect impact on the natural environment and human health |
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103. Persistence of a soil pollutant |
The duration of the persistence of the activity of a soil pollutant, characterizing the degree of its resistance to the processes of decomposition and transformation |
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|
104. Detoxify Soil Pollutant |
Converting a soil pollutant into compounds that are non-toxic to organisms |
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105. Sanitary condition of the soil |
The totality of physico-chemical, chemical and biological properties of the soil, which determine its direct impact on human and animal health |
||
3. An alphabetical index of the terms contained in the standard in Russian is given in Table. 2.
4. Terms and definitions of concepts established in ST SEV 5298-85, but not used in the USSR, are given in the Appendix.
5. Standardized terms are in bold, their short form is in light, and invalid synonyms are in italics.
table 2
ALPHABETIC INDEX OF TERMS IN RUSSIAN LANGUAGE
|
Term number |
|
|
Soil unit |
|
|
Biological accumulation in soil |
|
|
Soil biological activity |
|
|
Soil analysis |
|
|
Areal soil elementary |
|
|
Soil appraisal |
|
|
Soil buffering |
|
|
Soil buffering acid-base |
|
|
Specific humus substances |
|
|
soil pollutant |
|
|
Soil organic matter |
|
|
Soil type |
|
|
soil moisture |
|
|
soil moisture capacity |
|
|
Soil air capacity |
|
|
Soil self-cleaning time |
|
|
Soil extractor |
|
|
soil leaching |
|
|
soil horizon |
|
|
Gumin |
|
|
humification |
|
|
Humus |
|
|
soil degradation |
|
|
Soil pollutant detoxification |
|
|
soil anion exchange capacity |
|
|
Soil cation exchange capacity |
|
|
Soil pollution |
|
|
soil pollution global |
|
|
Soil pollution local |
|
|
Soil pollution regional |
|
|
soil acidification |
|
|
Soil salinization |
|
|
Soil alkalization |
|
|
Soil use rational |
|
|
Source of soil pollution industrial |
|
|
Source of soil pollution agricultural |
|
|
The source of soil pollution is transport |
|
|
Source of household soil pollution |
|
|
soil depletion |
|
|
Mapping |
|
|
soil mapping |
|
|
Soil acidity |
|
|
Hymatomelanic acids |
|
|
Humic acids |
|
|
Humic acids |
|
|
Soil classification |
|
|
The amount of pesticides in the soil is residual |
|
|
Soil colloids |
|
|
Soil absorption complex |
|
|
soil consistency |
|
|
Soil pollution control |
|
|
The maximum permissible concentration of a soil pollutant |
|
|
fine earth |
|
|
Migration of chemical compounds |
|
|
Mineralization of the soil solution |
|
|
Soil pollution monitoring |
|
|
soil swelling |
|
|
Soil ion exchange |
|
|
Soil bases are exchangeable |
|
|
Soil protection |
|
|
Soil passport |
|
|
Soil pollutant persistence |
|
|
soil fertility |
|
|
soil density |
|
|
Soil trial site |
|
|
Mobility of chemical compounds in soil |
|
|
Soil acidification |
|
|
Soil subtype |
|
|
Soil alkalization |
|
|
Soil cover |
|
|
The soil |
|
|
soil fatigue |
|
|
Soil sample absolutely dry |
|
|
Soil sample air-dry |
|
|
Single soil sample |
|
|
Soil sample combined |
|
|
Soil sample mixed |
|
|
Pore space in the soil |
|
|
soil profile |
|
|
soil type |
|
|
soil discharge |
|
|
Soil type |
|
|
Soil self-purification |
|
|
Selectivity of ion exchange in soil |
|
|
soil skeleton |
|
|
Soil organic-mineral compounds |
|
|
Easily soluble soil salts |
|
|
Soil salts, sparingly soluble |
|
|
Composition of humus group |
|
|
Fractional composition of humus |
|
|
Soil composition granulometric |
|
|
Soil condition sanitary |
|
|
Degree of humification of organic matter |
|
|
The degree of saturation of the soil with bases |
|
|
Soil cover structure |
|
|
Soil structure |
|
|
The amount of exchangeable cations in the soil |
|
|
The amount of exchangeable bases in the soil |
|
|
soil type |
|
|
Soil-forming factors |
|
|
Soil fraction silty |
|
|
Soil fraction mechanical |
|
|
Fulvic acids |
|
|
Soil chemical characteristics |
|
|
Part of the soil is hard |
|
|
Soil alkalinity |
|
|
soil mechanical element |
|
|
soil erosion |
APPLICATION
Reference
|
Definition |
|
|
1. Soil-forming substrate |
The weathered part of the earth's crust from which soil formed and develops |
|
2. Type of soil-forming substrate |
Classification unit of a soil-forming substrate that has similar characteristics in terms of texture and formation |
|
3. Pedotop |
Homogeneous soil spatial unit, the features of which vary within a certain interval |
|
4. Podochore |
A heterogeneous soil spatial unit consisting of several pedotopes that have a certain pattern of distribution |
|
5. Soil shape |
Classification unit of soils, defined by a combination of soil type or subtype and soil-forming substrate |
|
6. Soil quality |
Characteristics of the properties and composition of the soil, which determines its fertility |
|
7. Heterogeneity of the soil cover |
Spatial differentiation of soil cover characterized by differences in the properties and location of soils or pedotopes |
|
8. Homogeneous (heterogeneous) soil cover |
Ground cover containing at least 75% of the area with similar soil properties |
|
9. Mechanical composition of the soil |
|
|
10. Soil organisms |
The totality of plant and animal organisms whose life takes place entirely or mainly in the soil |
|
11. Soil reaction |
The amount of free protons contained in the soil solution |
|
12. Optimum soil chemical content |
|
|
13. Soil absorption capacity |
A quantity that quantitatively expresses the ability of the liquid and solid phases of the soil to withstand a change in the reaction of the environment when a strong acid or alkali is added |
