UA70406U - Method for evaluation of physical quality of soil - Google Patents

Abstract

A method for evaluation of physical quality of soil includes determination of compactness of structure, content of water-stable aggregates. One additionally determines power of humus, or the first from the surface genetic horizon, humidity of stable plant fading, the least (field) moisture capacity of soil, content of macro-aggregations with agronomically useful dimensions, total specific surface of elementary (granulometric) particles of soil, with determination of integrated index of physical quality of soil by the sum of all the seven individual characteristics with comparison to the maximal parameter in the sample one determines quality of soil and its suitability for growing specific agricultural cultures.

Description

The useful model belongs to the field of agriculture and can be used in soil science, agrochemistry, ecology, economics, land use to assess the physical quality of soils as a component of their overall quality, to determine the degree of suitability of the physical characteristics of soils to agrotechnological and mechanical loads, and also as a basic a component of the overall assessment of the agronomic quality of soils.

The method can be used to evaluate soil cover in order to justify the scale of implementation of agricultural measures that affect the physical condition of the soil, optimization of the structure of sown areas, and implementation of innovative high-cost technologies for growing agricultural crops.

With the increasing degradation of agricultural lands, the need to restore soil resources by improving soil quality is increasing. Soil quality can be defined as the degree of suitability for specific functions that the soil performs in a certain geoecosystem.

The main function of soils is production capacity, i.e., ensuring the conditions for growing agricultural crops.

Soil quality consists of three parts, one of them is physical quality, which is directly or indirectly related to the other two - chemical and biological. High physical soil quality is the presence of an agronomically useful structure, resistance to erosion and compaction, and the ability to support root growth. High physical soil quality means the optimal ratio of solid, liquid and gaseous phases in the soil to ensure the optimal amount of air, water and dissolved nutrients for maximum yield and minimum environmental degradation.

There is a way to determine the potential resistance of soil to degradation and erosion I. Yu. Kapepii 0. E.

Zoi IKapep I. 0. v Bon 0. E. A yPateuogkKk og maYitsayop rpuvzisa!Y api spetisai! ipaisayogv oi voiiY atsaiiyu. Ip aeiiipipud zoiYi doainu tog a zyviaipariye epmigoptepi. ). MU. YuBogap, Yu. b. SoIetap, 0. E.

Vegaiisek, V. A. sieulati (adv5.). 5 o'clock wasps At. Brescia! ribiisayop po. 35, 1994.- P. 53-72), which includes determination of the following indicators: filtration, density and hardness, floating index, carbon content of total, free, mobile and microbial biomass, enzyme activity and total nitrogen content.

The priority of each of the indicators is determined using weighting factors. For

A number of equations are used to convert the real measured parameters of the indicators into relative values (on a scale from 0 to 1). According to the results of the measurements of the parameters of the indicators, depending on the tillage system (no tillage, chisel and plow), a parametric assessment of the quality of the soil in points is determined.

This method of integration is intended for evaluating the change in the properties of the arable layer of the soil under the influence of the types of its use and cultivation. The method cannot be used to compare soils of different genesis or even the same soil in different regions, due to the high climatic dependence of biochemical indicators and the absence of granulometric composition indicators in the set.

The closest to the proposed one in essence is the domestic method of physical characteristics of the soil - the index of physical condition |Medvedev V.V., Laktionova T.N. Bonytirovka soil according to agrophysical parameters // Scientific principles and practical methods! increase in soil fertility in the Urals and the Volga region/ Theses. acc. 11 n.-prod. conf. agricultural and agriculture Ural and

Volga Region, Ufa, 1988. - P. 55-57). The physical condition index was calculated on the basis of 7 main indicators - structure density, the content of the structural fraction of 10-0.25 mm, the content of water-resistant aggregates more than 0.25 mm in the layer of the preferred location of the root system of plants (0-50 cm), the lowest moisture capacity (H ), the porosity of the aeration at the LV and the range of active moisture (in the 0-100 cm layer) and water permeability (from the surface). A positive point is the calculation of the Index as a geometric mean value, which objectifies the calculations.

To calculate the physical condition index, those indicators were chosen that characterize changes in the soil condition in the root layer. These indicators are dynamic and can be used to solve certain monitoring tasks or another way of controlling changes in soil properties under the influence of anthropogenic factors. But precisely because of the dynamic nature and the lack of information about the granulometric composition, the indicators cannot be used to compare the physical quality of soils of different genesis in a certain area.

In contrast, the soil physical quality index includes stable indicators (such as the specific surface area of granulometric fractions and wilting moisture), which can be used to characterize not only the dynamics of the state, but also the genetic physical quality of the soil.

In addition, the process of calculating the integrated index of physical condition includes comparison with optimal parameters without taking into account the type and granulometric composition of the soil, while the newly created index of physical quality is calculated relative to the maximum values in a separate sample of soils of a certain type and grain size class.

The basis of a useful model is the task of improving the method by expanding the set of indicators of agrophysical quality, taking into account the type and granulometric composition of the soil and increasing the objectivity of the obtained results for assessing the functional suitability of arable soils and the justification of agrarian policy in expressivity.

The problem is solved by the fact that in the well-known method of assessing the physical quality of the soil, which includes the determination of the density of the structure, the content of water-resistant aggregates, according to a useful model, the power of the humus, or the first genetic horizon from the surface, the humidity of persistent wilting of plants, the smallest ( field) moisture content of the soil, the content of macroaggregates of agronomically useful size, the total specific surface of elementary (granulometric) soil particles and determine the integrated index of the physical quality of the soil by the sum of all seven individual indices, comparing which with the maximum parameter in the sample determines the quality of the soil and its suitability for cultivation certain agricultural crops.

An integrated assessment of the physical quality of the soil is determined by a minimum set of indicators that characterize: soil habitus (the strength of the humus, or the first genetic horizon from the surface), the ability of the soil to retain moisture and provide it to plants (the lowest moisture capacity and moisture withering), the structure of the root layer (structure density and structure), soil resistance to water (content of water-resistant aggregates) and the specific surface of granulometric fractions, which is a geometric characteristic of the soil for an objective assessment of its dispersion and reactivity. Thus, the soil physical quality index is a complex 7-component relative assessment of the agrophysical quality of the first soil genetic horizon from the surface.

Numerous studies have made it possible to establish that the main indicators of the physical quality of the soil are the following indicators: 1) the thickness of the humus, or the first genetic horizon from the surface (cm); 2) the equilibrium density of the structure (volumetric mass) of the soil (g/cm3, investigated by the method of incised rings of N. A. Kachynskyi); 3) humidity of permanent wilting of plants (95, investigated by the method of plant miniatures and calculation due to maximum hygroscopicity

From the ground); 4) the lowest (field) moisture capacity of the soil (965, investigated by the method of flooding sites in the field); 5) the content of macroaggregates of agronomically useful size - 0.25-10.0 mm, (according to the method of N. Savvinov); b) the content of water-resistant aggregates larger than 1 mm (95, according to the method of sieving in water by N. Savvinov) and 7) the total specific surface of elementary (granulometric) soil particles (m/g, calculated according to the geometric method).

The method consists in determining the soil physical quality index for selected objects using experimental soil data in the following order: 1. Data samples are created according to the following limiting criteria:

A) to compare the quality of one and the same soil in different places of its occurrence - soil type, subtype, species, variety (gross composition according to the content of physical clay), genetic horizon;

B) to compare the quality of different soils within a certain territory, for example, an administrative region or a natural-agricultural district - signs of belonging to a given territory and a genetic horizon. 2. The maximum values of each indicator are determined in the data sample (1);

C. To ensure the possibility of comparing different indicators, real parameters (x) are converted into relative parameters (y) according to the formulas we obtained, which are given in the table. 1: - for indicators for which the highest parameters (1,2,4,6, 7) are the best:1 - x/1 LI. - for indicators for which the lowest parameters (3, 5) are the best: and - 1-(х/1.13.

That is, individual indexes are determined for each row in the data sample. 4. An integrated index of the physical quality of the soil is determined by the sum of all seven individual parameters for each line in the sample, and then, according to the task, for certain types of soil or for specific territories, or the degree of optimality of the criterion is determined, as 9o the average value of the index in the sample from as much as possible.

Table 1 shows indicators of the physical quality of the soil and formulas for converting absolute parameters into relative ones.

Table 1 of the day in parameter set 6 |Content of water-resistant aggregates» 1.0 mm, 96 0 Tsivekh/Lv 77777771 1) - ии...и7 - converted (relative) parameter - individual index; x...x7 - measured sample parameter, y....7 - maximum measured parameter of each indicator in the sample, 1.1 - coefficient for increasing the maximum parameter (1.11 - limit parameter).

An example of the method of assessing the physical quality of the soil.

The index of physical quality was determined for the main arable soils of the Kharkiv region according to the nomenclature list to the map scale 1:750000 according to the type B sample. An example of the calculation of the integrated index from individual indices based on separate indicators for two soils is presented in Table 2.

Table 2

Index. . . Petoma and . The most Content Content physical

Type of soil, Power- | Gap-| Volo- smaller macro-water surface granulometric | ness of H- | ness | a guest and granulo-: the composition of the hill- | will be | withered- volo- | aggregates) of stable metric qualities of the umbrella taken out M- (0.25-10 | aggregates of them runnability MM) (21 mm) -- | (IFYAG) factions

Dark gray gilded 0.56 0.34 | 0.50 0.46 0.70 0.02 0.47 3.05 heavy loam

Typical low-humus chernozem 0.78 0.34 | 0.40 0.53 0.78 0.27 0.58 3.68 light clay

According to a similar scheme, the results of the assessment of the physical quality of all soils were obtained

Kharkiv region, and the obtained data were summarized in Table 3.

According to the obtained data, the physical quality of arable soils of the Kharkiv region is determined by the index, the parameters of which do not exceed 2.75-3.73 and are the highest in soils of the chernozem type of heavy granulometric composition. The degree of optimality of the physical quality of each soil (relative to its best possible physical state) shows a more noticeable difference between types and subtypes of soils. The greatest potential is realized in meadow and chernozem-meadow soils of heavy loam granulometric composition, where the average value of the index in the sample in the region differs from the maximum value by only 21 95. And the physical quality of dark gray podzolized medium loam soils (as a whole for the sample) differs from the maximum possible by 42 95. This allows us to assume that the first soil is more resistant to anthropogenic loads, and in the process of use will require less economic costs, that is, it is more suitable for growing main crops and more attractive for agricultural investment.

Thus, the index of physical quality of the soil (IFYAG) can be used for various types of assessments. For example, the following: - to assess the functional suitability of arable soils, i.e. the suitability of soils on the territory of the region for the cultivation of various agricultural crops with certain requirements for soil conditions;

- for zoning the territory according to suitability for various methods and depths of soil cultivation and, including, to minimize cultivation; - to find areas where innovative agricultural technologies, technical means and agrochemicals can be applied with maximum efficiency; - to substantiate the agrarian policy in the region regarding the support of commodity producers taking into account the quality of the soil on which they work.

Other assessments are also possible, when the integrated index of physical soil quality will provide objectivity in determining changes in soil quality under the influence of long-term use of certain technologies, monoculture, irrigation, etc. IFYAG also has prospects of application to evaluate the results of the research network in the region (where and how the same agricultural measures are studied).

Table C

Index of physical quality. Granulometric maximum degree

Sampling - soil of the wound P average In the composition of the value in the optimal value NI h og) selectivity, 90

Dark-gray podzolized soils | medium loamy

Deep, low-humus chernozems medium loamy

Dark gray podsolized soils | heavy loamy

Black soils are common. r and medium loam 3.07 5.34 57 medium humus

Chernozems are heavy loamy podzolized

Deep, low-humus chernozems heavy loamy

Black soils are common. ry. heavy loam 3.27 4.90 67 medium humus deep

Black soils are common. medium loam 3.28 4.87 67 medium humus deep

Luchno-chernozem deep-. . heavy loam 1 4.7 saline soils U 3.3 Z

Black soils are common. r and heavy loam 3.35 4.73 71 medium humus

Gray podsolized heavy loamy soils 8539 | 512 | 66

Deep medium-humus chernozems and chernozems. red humus re light clay 3.39 5.21 65 deep medium humus carbonate

Black soils are common. ry. light clay 3.52 5.18 medium humus deep

Deep medium-humus chernozems and chernozems. red humus pH heavy loam 3.56 5.11 70 deep medium humus carbonate

Deep, low-humus chernozems light clay

Meadows and chernozemno-meadows.

In the mouth of heavy loamy 3.73 4.73 79 deep saline soils 1!) to calculate the maximum value of the physical quality index, the best parameters of the indicators in the samples were used 2) the degree of optimality - the share of the average value of the index in the sample from the maximum possible, 905.

Claims (1)

USEFUL MODEL FORMULA The method of assessing the physical quality of the soil, which includes the determination of the density of the structure, the content of water-resistant aggregates, which is distinguished by the fact that the capacity of the humus or the first genetic horizon from the surface, the humidity of persistent wilting of plants, the smallest (field) moisture capacity of the soil, the content of macroaggregates are agronomically determined useful size the total specific surface of elementary (granulometric) soil particles and determine the integrated index of physical soil quality by the sum of all seven individual indicators, comparing which with the maximum parameter in the sample, determine the quality of the soil and its suitability for growing certain agricultural crops.