Clause 16 of the Reforestation Rules states:

Promotion of natural reforestation through soil mineralization is carried out in areas where there are sources of seeds of valuable tree species of forest plantations (adjacent forest plantations, individual seed trees or their groups, clumps, strips, under the canopy of forest plantations entering felling with a density of no more than 0.6) .

Soil mineralization should be carried out in years of satisfactory and abundant harvest of forest seeds. The best time for mineralization of the soil surface is before the seeds of forest woody plants begin to fall.

Work is carried out by treating the soil with mechanical, chemical or fire means, depending on the mechanical composition and moisture of the soil, the density and height of the grass cover, the thickness of the forest floor, the degree of mineralization of the soil surface, the number of seed trees and other site conditions.

In clearings and plantings where soil mineralization is planned, permanent trial plots of 0.5-1.0 hectares are established to assess the effectiveness of these measures. Their number is established depending on the size of the plots, but not less: on areas up to 10 hectares - one; from 10 to 25 - two; over 25 hectares - three. The trial plots are divided into two parts: one is left for control, the other for carrying out such activities as throughout the entire site. On each part of the trial plot, undergrowth and self-seeding of all species are taken into account.

Counts of self-seeding and young trees aged two years and older are carried out on counting plots measuring 2x2 m, laid in rows at the same distance. The number of rows (passes) must be at least three in each trial plot. The total number of sites is at least 25.

Accounting data is entered into registration cards, which serve as the basis for filling out a list of areas designated to promote natural regeneration, and a notebook (book) for recording areas with measures taken to promote natural regeneration.

In addition to logging, natural regeneration can be promoted under the forest canopy. Soil mineralization to promote natural reforestation is carried out in forest stands with a crown density of no more than 0.6 and in places where there is no undergrowth. In spruce forests, soil mineralization occurs 7-10 years before felling, and in pine forests - 3-5 years. In pure coniferous forest stands, the soil is mineralized in late summer and autumn, in mixed forest stands with the participation of deciduous species in the composition of more than 0.1 - in late autumn after the leaves have fallen.

Tree stands in which soil mineralization has been carried out to promote regeneration are subject to felling in winter.

Soil mineralization is not carried out in clearings with relatively fertile or wet soils.

The size of the cultivated area under the forest canopy should be at least 15-20% of the area of ​​the site, in clearings - 30%.

Methods and technical means for removing ground cover are selected depending on the types of trees, their growing conditions, the degree of turf, the type of soil, its moisture and density, etc.

In clearings with dry and fresh sandy, sandy loam soils in groups of forest types: lichen, heather and lingonberry pine forests, soil mineralization to promote the natural regeneration of pine is carried out in strips 20-30 cm wide to a depth of 5-7 cm. In non-turfed 1-3-year-old clearings with In fresh and moist sandy loam and light loamy soils in groups of forest types: pine and spruce forests, complex and blueberry forests, soil mineralization is carried out in strips at least 1 m wide to a depth of 7-9 cm. In clearings with loamy and heavy loamy damp and wet soils in forest types: long-moss pine forests and blueberry-small-grass spruce forests and brook rivers, soil mineralization in clearings is carried out by plowing layers 10-20 cm thick. The distance between mineralized strips or layers should be 2-5 m.

To mineralize the soil in clearings and under the forest canopy, special cover strippers are used - seeders, cultivators and plows.

In fresh fellings in sorrel and similar forest types, shallow loosening is recommended with the removal of the soil layer and litter to the surface of the humus horizon, carried out using forest plows PKL-70, PLP-135, PL-1, etc. When processing with PKL-70 plows , forming a mineralized strip width of 1.4 m, furrows are laid every 2-4 m, and when processing with PLP-135 plows, creating a mineralized strip 2.7 m wide - after 5-6 m. On sites with wet and damp soils (with excessive moisture), soil mineralization is combined with drainage measures, laying a network of furrows through 10-30 m. For this purpose, they use PKLN-500 ditch plows, LKA-2M and LKN-600 ditch-diggers, and even TE-3M, E-304V, E-5015, etc. excavators. This equipment is recommended for use on long-lasting, sphagnum, meadowsweet, lancet-reed, etc. types of clearings with waterlogged soils.

In most cases, these plows are used for their main purpose - to prepare the soil in clearings and under the forest canopy, during artificial reforestation and reclamation work. They will be discussed in more detail below. More often, when mineralizing the soil in order to promote natural regeneration, various types of cover strippers, rippers, cultivators and cutters are used. These tools perform loosening with simultaneous mixing of the litter and the upper mineral horizon in strips 0.5-2.0 m wide to a depth of 5-10 cm. The distance between the loosened strips, depending on the success of natural regeneration, is 2-4 m in clearings, and under the canopy forests - 3‑6 m. Distance between loosened strips b can also be calculated using the formula:

Where B– working width of the unit;

k m– the mineralization coefficient adopted to ensure the receipt of a sufficient amount of undergrowth of main species (10-20 thousand pieces per 1 ha) equal to k m=0.25-0.30 area with unsatisfactory natural renewal;

k rho– coefficient that takes into account the degree of mineralization in the processed strip depending on the type of working parts of the implements and is taken equal to: 1.0 – for plow bodies; 0.5-0.6 – for machines with disk working bodies with a single pass and, respectively, 0.7-0.8 and 0.9-1.0 – with two- and three-track processing;

k doors– coefficient taking into account the nature of the movement of the implement, taken equal to 1.0 for strip processing, and 1.85 for cross processing.

The anchor peeler YAP-1 (Fig. 2.1) is intended for preparing the soil in ungrazed clearings and under the forest canopy by stripping the vegetation cover to the surface of the humus horizon. It consists of two dimensionless anchor-type sections connected by a chain. The first section is lighter and has the shape of an irregular hexagonal pyramid, to the base of which working bodies in the form of paws are welded. The second section is heavier and has an oblong shuttle-shaped shape, with ripping arms welded in the middle of the base. When the anchor peeler operates, the paws of the front section rip off the ground cover, and the paws of the rear section loosen the mineral soil to a depth of 4‑5 cm. The YAP-1 is mounted on tractors TDT-55, Onezhets-300, TLT-100, TDT-44 or LHT-55 , to which it is connected by a chain.

Rice. 2.1. Anchor skin peeler

On ungrown clearings with the number of stumps up to 800 pcs. for 1 hectare, littered with logging residues, dead wood, stones, as well as in wastelands and burnt areas, cover strippers-rippers are used (Fig. 2.2) RL-1.8 and PL-1.2, aggregated with tractors Onezhets-300, TLT-100, TDT-55, LHT-55, T-100M, etc. They are designed for stripping forest litter and moss cover while simultaneously loosening the soil in strips to promote natural regeneration. The RL-1.8 ripper consists of a frame with consoles and a trailer, a shaft with a double-sided bracket, working parts in the form of teeth, two wheels with stops, locking and locking mechanisms. At the rear of the frame there is an axle with brackets into which chisel-shaped teeth are inserted. At the ends of the axle there are wheels with stops and semicircular grooves. When transporting implements over long distances, plugs are inserted into the grooves, which give the wheels a normal round shape. When the unit moves, the teeth go deep into the soil and loosen it. When encountering an insurmountable obstacle or when the teeth are clogged with dead wood, the locking mechanism releases the wheels, and they begin to rotate the axle with teeth 180°, after which the second row of teeth takes the working position, and the locking mechanism locks the wheels again. Thus, the ripper teeth seem to “step over” obstacles. The forest cover peeler PL-1.2 has a similar device and operating principle.

Rice. 2.2. Forest cover peeler

Disc implements are widely used for soil mineralization in clearings: forest ripper RLD-2, disc cultivator DLKN-6/8, disc cover stripper PDN-1, furrow cultivator KLB-1.7 (the main purpose is to care for crops planted in the bottom of furrows ). The design and principle of the influence of the working bodies on the soil are largely similar. Disc guns use spherical solid or cut-edge (more often) discs mounted at an attack angle of up to 45°. The disks are assembled into batteries by placing them on a square axis and installing bearing coils between them, which ensure, in addition to a strictly maintained distance between the disks, rotation in the bearings (Fig. 2.3).

Rice. 2.3. Disc peeler

The RLD-2 ripper (Fig. 2.4) has a battery consisting of two disks. The batteries are placed along the tracks of the tractor tracks, which protects the disk batteries from impacts, because the tractor driver chooses a direction of movement that prevents the tracks from hitting stumps. In addition, the use of spring-loaded stands, which allow the discs to deflect when encountering stumps or roots, protects the batteries from damage. Safety springs are found on guns such as PDN-1 and KLB-1.7. The latest guns provide for adjustment of the angle of attack of the discs due to rotating devices consisting of movable and fixed plates, fixed with bolts in the adjustment holes. These guns also provide adjustment of the stroke depth up to 10-12 cm through the use of ballast boxes.

In the PDN-1 skin peeler, spherical disks are installed on balancers and arranged in a herringbone pattern, with the front and rear disks overlapping each other in the transverse plane. The balanced suspension allows the discs to follow the microrelief and ensures a high degree of soil mineralization. In the middle part of the implement frame, in front of the disks, a spring-loaded ripper arm is hinged, which deflects when it encounters an obstacle. Using a ballast box mounted on the rear of the frame, the working depth can be adjusted up to 12 cm.

Rice. 2.4. Forest disk ripper RLD-2:

1 – battery disk; 2 – stand; 3 – safety spring; 4 – frame; 5 – hitch; 6 – seed drum; 7 – shaft; 8 – friction drive; 9 – spring

In strip tillage, areas set aside to promote natural reforestation through soil mineralization are divided into paddocks. It is advisable to take the length of the rut at least 200 m, and the width - at least 100 m. With smaller plot sizes, a significant part of the time is spent on idle travel at the end of the rut.

In wild rosemary and sphagnum pine forests, bog cutters FBN-0.9 and FBN-1.5 are used for milling peat with simultaneous rolling for capillary rise of moisture. In fresh and underdeveloped felled areas with the number of stumps up to 600 stumps/ha, the FLU-0.8 forestry cutter is used to promote natural regeneration (Fig. 2.5). The design of these cutters is similar, while the FLU-0.8 cutter is unified with the FBN-1.5 cutter. The main components of the cutter are: a frame with an attachment, a cardan transmission, bevel and spur gearboxes, a milling drum, a rake grid, a mechanism for adjusting the processing depth and a protective casing.

Rice. 2.5. Diagram of the FLU-0.8 cutter:

1 – attachment; 2 – protective casing; 3, 4 – bevel and chain gearboxes; 5 – adjustment holes for the deepening mechanism; 6 – rake; 7 – milling drum; 8 – limit skid; 9 – hinge of the limit skid; 10 – frame; 11 – cardan transmission

The working part of the cutter is the milling drum. It contains driving and driven disks that interact with each other through friction pads. Eight L-shaped knives are attached to each driven disk: four right and four left. The driven discs with knives sit freely on the shaft, and the driving discs with friction linings are mounted on the shaft on splines. The driven and driving disks are pressed by their working surfaces against each other using springs. Transmitting rotation to the driven disks using friction clutches allows them to slip on the drum shaft when encountering insurmountable obstacles in the form of stumps, stones, large roots, logging residues, etc., and thereby protect the knives from breakage. The actuation moment of the clutches is adjusted by compressing the springs using two adjusting nuts located on the sides of the milling drum. The processing depth of the FBN-0.9 and FBN-1.5 cutters is up to 20 cm, and the FLU-0.8 cutter is up to 16 cm.

When the tractor moves with the power take-off shaft turned on, the milling drum rotates, and its L-shaped knives crush soil and roots with a diameter of up to 4 cm, throwing the crushed mass onto a rake grid, which additionally crushes large fractions of turf. Plant residues and large fractions are retained by the grate and remain in the lower part of the treated soil layer, and small fractions pass through the rake grate and fall asleep on top of the treated layer. In one hour of operation, the cutter can travel up to 3 km.

It should be noted that promoting natural regeneration can be successful when 15-25% of the cleared area is treated. Since soil mineralization is a labor-intensive process, it should be resorted to when there is a sufficient amount of seed deposits from the seed plants or the forest wall. If there are seeders with a yield not lower than average, the soil should be cultivated at a distance of no more than 100 m. In deciduous plantations, the soil is cultivated after the leaves have fallen. When prescribing soil tillage with implements to promote natural regeneration, one should take into account the percentage of mineralization obtained during timber harvesting (removal of litter by machines and moving trees and canes). After self-seeding appears on mineralized strips, it is necessary to systematically care for it. Given this, it may be that the cost of promoting natural regeneration may be close to the cost of establishing forest crops. In this case, it may be more expedient, in the absence of a shortage of labor resources, to switch to artificial reforestation.

Already in the process of cultivating the soil in a forestry area, mechanical damage to the upper soil layers occurs, as a result of which plants and their remains are removed from the surface and the mineral part of the soil and even the soil is exposed. This kind of qualitatively changed surface of a forested area, even in the case of partial soil cultivation, can become a significant obstacle to the advancement of fire during ground fires.

In conditions of dry pine forests, increased planting density of pine crops and increased standing density are a necessary biological property of pine forests. However, in this case there is a concentration of dead organic matter (needles, twigs, bark flakes, i.e. litter), which provides food for fire in a ground fire. Therefore, a preventive measure against fires inside dry forest stands is loosening of interradial spaces, in as a result of which undecomposed dry litter and litter, mixing with mineral particles of the soil, lose their flammable properties and decompose faster. It is advisable to carry out such loosening after 2–3 years. If, in the period between loosening, a quick fire occurs, then its action and consequences are less dangerous (Schmidt, 1948).

Carrying out soil mineralization by loosening row spacing, plowing young pine trees, as well as by laying mineralized strips and fire ditches, they are actually working to create simple fire barriers. Their functioning should be considered as an effective method of preventing forest fires.

Mineralized stripes– these are linear sections of the territory cleared from forest combustible materials to the mineral layer of soil or treated with tillage tools or in another way . The main purpose is to delay the spread of ground fire or serve as a support line during annealing and starting a counter fire. Mineralized strips are sections of territories , With which have removed almost all groups of above-ground forest combustible materials. They are the main preventive measure aimed at preventing the penetration of fire into forested areas. Mineralized strips can be an independent fire barrier or be part of a more complex fire barrier as an element.

Mineralized strips can be created with general and special-purpose soil-cultivating implements - PKL-70, PLP-135 plows, agricultural plows, forestry cutters, bulldozers, special tractor strip blowers PF-1, tractor and manual soil throwers. The type of weapon is determined in each specific case. Mineralized strips are also formed when wood is skidded along skidding trails laid in plantations during thinning, which must be taken into account and used when developing a plan for laying mineralized strips. The current rules for protecting forests from fires establish only the minimum width of the protective mineralized strip - 1.4 m. It is created in one pass of the PKL-70 double moldboard plow.

The mineralized strip can “work,” i.e., delay the advance of ground fire only until a new layer of combustible materials accumulates on its surface. Therefore, it is necessary to provide for systematic care of mineralized strips, their renewal and restoration. Typically, if a mineralized strip is created in the spring, it is cared for in the fall, and the following year - in the spring and fall.

The amount of care depends on local forest conditions and the method of creating strips; One maintenance per fire season may be sufficient. When leaving, the same tools are used to make strips. For example, the stripes created by the PKL-70 plow can be maintained using forest disk cultivators. When developing master plans for forest fire protection, the general need for mineralized strips is determined for forest districts and enterprises in general.

Fire ditches are arranged to protect valuable forests from possible underground (peat) fires. Fire ditches are laid along the boundaries of peat bogs, on their territory and in plantings with peat soils; the depth of the ditches is to the mineral layer of the soil or to the groundwater level. Drainage channels also serve as fire ditches, provided they are filled with water. The network of fire ditches should, as a rule, be closed so that there is no room for fire to pass through the peat layer.

Peat processing enterprises located on the territory of the forest fund are required to separate the operational area of ​​the peat deposit from the surrounding forests with a fire-prevention gap 75–100 m wide. A drainage channel is laid along the inner edge of the gap (from the peat enterprise), the dimensions of which are (width at the bottom, at the top and depth) determined by a special project.

Fire ditches are laid by ditch diggers (if the thickness of the peat layer is small), by excavators - on thicker peat bogs, using an explosive method. Blasting operations are permitted only subject to full compliance with the “Unified Safety Rules for Blasting Operations” and are carried out, as a rule, by specialized organizations. The depth of ditches or channels laid in one pass by plow ditchers is 0.6–1.2 m (depending on the brand of ditch digger); bottom width – 0.2–0.4 m; width at the top – 1.5–2.8 m.

^ 9.2 Soil surface mineralization

Mineralization of the soil surface is carried out in the presence of fertilizers in order to create favorable conditions for seed germination and survival of seedlings under the canopy of plantings entering the felling with a density of no more than 0.6, in clearings and clearings by treating the soil with mechanical, chemical or fire means, depending on the mechanical composition and soil moisture, density and height of ground cover, thickness of litter, degree of mineralization of the soil surface during logging operations, number of seeders and other site conditions. The proportion of the mineralized surface should be at least 30% of the area of ​​the entire site. Plowing and milling strips should be located no closer than 5 m from seed crops or 2-3 m from groups of surviving undergrowth and undergrowth.

Optimal timing for mineralization of the soil surface

In the year of fruiting in late summer or autumn, and in some cases - in early spring of the next year, with simultaneous planting of seeds that fell in the autumn-winter period.

Soil mineralization must be carried out in the seed year with a seed harvest of at least the third point.

Tree stands, under the canopy of which, after mineralization of the soil surface, self-seeding of the main species has appeared, are subject to felling during the period when its greatest preservation is ensured.

^ 9.3 Fencing of clearings

If there is a risk of damage to young trees by domestic and

wild animals, areas with natural reforestation should be

fence on all sides or in places where livestock is driven.

^ 9.4 Leaving seeders

Leaving seed trees (trees and clumps) is a mandatory silvicultural measure during the allocation and development of cutting areas as the most important condition for ensuring regeneration, but is not included in the plan for promoting natural regeneration of the forest as an independent type of measure. The placement and quantity of pollutants left are determined by regional guidelines (manuals), rules of logging in the forests of Kazakhstan (2005).

The number of seeds (indicated in the logging ticket) left at the cutting site, their location and configuration depend on the biological characteristics of tree species, growing conditions, skidding methods, width of cutting areas, presence of undergrowth, etc. Seed plants must be wind-resistant, abundantly fruiting, with a good trunk shape , without hereditary defects.

In large clearings, where the spread of seeds from adjacent forests is excluded and when it is economically beneficial, it is advisable to leave seeds: seed seeds of free-standing wind-resistant trees of pine, larch, cedar, 15-30 pcs/ha; seed groups of 5-10 pieces/ha (in a group there are 3-6 pines, larches, cedars and sometimes spruces); seed clumps - forest areas with an area of ​​0.1-0.5 hectares of square, rectangular or other shape (in cutting areas wider than 200 m); seed strips - forest areas in the form of elongated strips 20-25 m wide. It is recommended to set aside spruce clumps measuring 40 X 50 m in the absence of excessive moisture and 60 X 60 m on damp soils (at a distance of 100-150 m from one another).

^ 9.5 Addition of fellings

In clearings where the amount of self-seeding, retained undergrowth and undergrowth is insufficient for successful natural regeneration of the forest, additional planting of seedlings and saplings is possible. In this case, the number of seats should not exceed 25% of the accepted norm.

for continuous forest crops under these conditions.

The results of the measures taken to promote natural forest regeneration are assessed in accordance with the current technical documentation approved by the authorized body. A tally sheet of the measures taken to promote natural regeneration of the forest is compiled, which is an appendix to the “Act of technical acceptance of areas with measures taken to promote natural regeneration of the forest.” The document is introduced after the work and takes into account the measures taken to promote the natural regeneration of the forest. The act of technical acceptance of measures taken to promote ES is introduced when accepting areas with measures taken to promote natural regeneration of forests. It reflects the implementation of planned activities in general and according to individual criteria.

10 Protective afforestation

^ 10.1 Adverse natural phenomena, their brief description

The climate on the territory of Kazakhstan is characterized by two important features: a small amount of precipitation and an abundance of heat and light during the growing season of agricultural plants. The discrepancy between the amount of heat and moisture increases from north to south of the republic.

The location of the southern regions of lowland Kazakhstan at fairly low latitudes gives the climate an arid character, as a result of which desert landscapes are developed here. To the north, aridity softens and desert landscapes give way to semi-desert, then steppe, and in the very north – forest-steppe.

Along with the continental climate on the territory of the republic, the frequency and strength of such unfavorable climatic phenomena for agriculture as drought, hot winds, dust storms, cold and blizzard winds is increasing.

^ Under the Drought one should understand an unfavorable combination of hydrometeorological conditions, leading to dry air and soil, in which the water balance in the plant body is disrupted, causing a sharp decrease or complete loss of the crop. Drought can be soil, atmospheric or general.

^ Soil drought is the depletion of water reserves in the soil. The causes of soil drought are the lack of autumn precipitation, snow blowing from fields, large surface runoff of melt and storm water, lack of precipitation in the spring and summer, violation of agricultural practices for growing crops, excess salts in the soil, causing physical dryness of the soil.

^ Atmospheric drought lies in the lack of moisture in the atmosphere. Most often it occurs at high temperatures and low relative humidity. Atmospheric drought includes periods with temperatures above 25°C and relative humidity less than 20%. At the same time, plants' moisture consumption for transpiration sharply increases, the productivity of moisture use decreases, and the root system does not have time to provide water supply from the soil. Atmospheric drought is an inevitable consequence of continental climate.

The combination of soil and atmospheric drought is called total drought. The most destructive is drought accompanied by hot winds.

Sukhovei is a complex of meteorological conditions that cause high evaporation. There are weak and strong dry winds. Weak dry winds occur when the wind speed is 5 m/s, the relative air humidity is below 20% and the air temperature is more than 25°C. Strong dry winds are observed when wind speeds are above 8 m/s, relative humidity is below 20% and air temperature is more than 30°C. Dry winds can last for several days in a row.

The occurrence of dry winds was previously explained by the arrival of dry air masses from deserts and semi-deserts. Currently, their occurrence is explained by intense air movement along the periphery of a stable anticyclone, in the center of which hot weather is usually observed.

Dust or black storms is the process of destruction and transfer of the upper horizons of soil by strong winds. They occur at different wind speeds: on light sandy loam soils at a wind speed of 10-12 m/s, and on cohesive soils at 12-15 m/s. Soils containing more than 50% of aggregates less than 1 mm in size are considered erosion-hazardous.

Black storms are observed more often in May-June, when the soil in the fields is still poorly covered with vegetation. They occur during the daytime and last from one to three hours. The number of days with dust storms, especially in Northern Kazakhstan, can reach 60 or more per year. The most destructive black storms, sometimes covering large areas of the steppe zone, recur every 5-10 years.

Blizzard and cold winds are also negative natural phenomena.

Blizzard winds blow snow from elevated places, wind-impacted slopes, and sometimes from flat fields into ravines and ravines. Often, soil particles are blown from the fields along with the snow.

When snow is blown from fields, the likelihood of winter crops and grasses freezing increases, the flow of moisture into the soil decreases, and preconditions are created for the occurrence of soil drought.

Cold winds in winter sometimes cause freezing of agricultural crops, as well as freezing of trees and shrubs in gardens and forests. In spring, cold winds cause damage to plants, delay their growing season, and contribute to the formation of local frosts.

To reduce the negative impact of the above-mentioned adverse natural phenomena, of all the means currently available to agriculture, the most effective and economically accessible is the use of various types of protective forest plantations.

^ 10.2 Types of protective forest plantations

Forest reclamation plantings, especially in combination with other measures, protect the soil well from erosion, increase the humidity of fields, and weaken the harmful effects of droughts, hot winds and dust storms. The yield of agricultural crops and the gross harvest of grain and other products in fields protected by forest belts is higher than in open ones, not only in years of drought, but also in favorable years. In addition, forest reclamation plantings reliably protect agricultural areas from destruction by washout and erosion.

It is very important to grow forest plantations along the banks of rivers, lakes, reservoirs, around gullies and ravines, along railways and highways to protect them from drifts of snow and sand, as well as the creation of forest plantations for the consolidation and economic development of sandy massifs.

Forest reclamation measures to protect soil from wind and water erosion and improve the microclimate provide for the creation of highly effective systems of contour-reclamation plantings of drainage areas, expediently located throughout the land use area, taking into account the terrain and the condition of the soil cover. This system includes the following types of protective forest plantations:

A) forest shelterbelts 9-12 m wide; they are placed on arable land in plain conditions and on watersheds to protect fields from the harmful effects of hot winds, blizzards and wind erosion;

B) water-regulating forest strips up to 15 m wide; they are placed on arable slopes to regulate surface runoff, reduce water erosion of soil, and improve the microclimate of fields;

C) ravine and ravine forest strips 15-21 m wide along ravines and ravines and gully-gully forest plantations inside ravines and ravines to regulate surface water flow, stop water erosion, economic use of unproductive lands, and improve the microclimate in adjacent fields.

In addition to these main types of reclamation plantings for agricultural fields, there are others that take into account the specifics of the protected territory:

A) forest strips on irrigated lands along irrigation and drainage canals to reduce water evaporation, lower groundwater levels, protect fields from dry winds and dust storms;

B) forest strips and plantings on pasture lands to increase the productivity of pastures and protect animals from wind and heat;

C) canopy and massive forest plantations on broken sandy soils not used in agriculture to consolidate sands and transform them into productive lands;

D) forest strips along roads to protect against snow and sand;

E) protective and decorative plantings in and around rural settlements to improve the environment;

E) forest plantations on mine dumps for their reclamation.

A properly created system of contour-reclamation plantings in an adult state is a unique device that, under constantly changing weather conditions, automatically regulates them, preserving the soil from wind and water erosion, improving the microclimate of the fields and the entire agricultural landscape in general. All this makes forest reclamation important in solving the problem of nature conservation and improving the natural conditions of agricultural production.

^ 10.3 Structures of forest strips

Protective forest plantings in most cases are a system of forest strips, the influence of which on the microclimate, soil, hydrological processes and agricultural yields depends on their design.

The design of forest strips refers to the degree and nature of their wind permeability. The design is determined by the ratio in the profile of the strip of gaps and dense (not blown) areas.

To successfully fulfill their main purpose in various soil and climatic conditions, forest strips are given an appropriate design - dense (windproof), moderately openwork, openwork, openwork and blown (Table 10.1)

Forest strips of dense construction consist of trees of all tiers and shrubs, with a high density of their placement and without gaps along the entire vertical profile. The wind flow usually does not pass through such a strip, but flows around it from above.

Stripes of moderately openwork, openwork and openwork-blown structures are also created from trees of different tiers and shrubs, but less dense, with small gaps along the vertical profile.

Table 10.1- Structures of forest strips

Constructions	Wind permeability in summer, %
	between the trunks	in the crown
Dense	0-10	0-10
Moderately openwork	15-20	15-20
Openwork	25-35	25-35
Openwork-blown	60-70	15-30
Ventilated	60-70	0

The strips of a ventilated structure are usually distinguished by one layer of trees and the absence of shrub undergrowth, as a result of which such strips are easily permeable to air flows in the lower ground layer. In the lower part, there are 1.5-2 m gaps between the soil surface and the tree crowns.

^ 10.4 Forest shelterbelts

Placement of shelterbelts. The requirement for the placement of shelterbelt forest belts is to ensure maximum protection of soil and crops from wind erosion, hot winds and strong winds with minimal occupancy of arable land for plantings.

The forest shelterbelt system consists of main and auxiliary strips of blown or openwork structures.

The main (longitudinal) stripes perform the main protective role and are placed perpendicular to the prevailing most harmful winds in the area.

In fields of complex configuration, it is allowed to deviate longitudinal forest strips from this direction, but not more than 30°.

Auxiliary or transverse forest strips are created perpendicular to the longitudinal ones in order to weaken the influence of harmful winds that have the same direction as the main strips.

The distances between the main forest belts are set depending on soil conditions and should not exceed:

On meadow-chernozem and leached chernozem - 500 m;

On ordinary and southern chernozems – 450 m;

On dark chestnut soils - 300 m;

On typical chestnut soils - 250 m;

On light chestnut soils – 200 m;

On gray soils – 300 m;

On steppe sandy loam soils - 300 m.

As for the distance between auxiliary (transverse) stripes, taking into account the productive use of agricultural machinery, it is set within 1500-2000 m.

With this placement of forest strips, the arable area will be divided into rectangular cells bordered by green ribbons.

For the passage of tractors with trailed implements and vehicles, gaps 20-30 m wide are left at the intersections of main and transverse forest shelter belts. In addition, for the same purposes, gaps up to 10 m wide are made in longitudinal forest belts every 500-700 m.

In the steppe regions of Northern and Western Kazakhstan, 2- and 3-row main shelterbelts with a row spacing of 3-4 m have the highest reclamation and protective properties. With the deterioration of forest conditions, tree species need to increase the feeding area. This requirement is met in practice by reducing the number of rows, increasing the row spacing and the distance between plants in the rows (Table 10.2).

Table 10.2 - Placement of plants in shelterbelts (row spacing, row distance, m) according to KazNIILKhA data

Preparing the soil for forest strips. The main goal of soil preparation in any soil-climatic zone is to create a good water and food regime, to provide the best conditions for the successful growth and development of the root system of tree and shrub species. With good soil preparation, woody plants take root better and grow faster, reducing the cost of supplementing plantings and agrotechnical care.

The soil for forest belts is prepared using the black or early fallow system. The black fallow system includes the sequential implementation of the following soil cultivation methods: stubble peeling with disk ploughers or flat cutters 10-12 days before the main plowing; autumn plowing with plows with moldboards to a depth of 25-27 cm with simultaneous rolling with ring rollers; in winter, 2-3 times snow retention; during the spring-summer period, 3-4 times continuous tillage of the soil with cultivators or flat cutters; autumn plowing with plows without moldboards or subsoilers to a depth of 35-40 cm.

The early fallow system includes: the main plowing of the soil in May with plows with moldboards to a depth of 25-27 cm with simultaneous rolling with ring rollers; 3-fold summer tillage of the soil with cultivators or flat cutters; autumn plowing of the soil with plows without moldboards or subsoilers to a depth of 35-40 cm.

The Kazakh Research Institute of Forestry and Agroforestry recommends preparing the soil for protective forest plantations using the black or early fallow system, but replacing the usual autumn fallow plowing with deep plantation plowing to a depth of 50-60 cm (the so-called “plantation fallow”). Such soil preparation promotes greater accumulation of moisture (15-30%) than conventional fallow, reduces soil salinity and, most importantly, destroys the compacted carbonate horizon, which creates favorable conditions for the active growth of root systems of woody plants.

Planting forest strips. The best time to plant forest strips is spring. If the autumn is wet and warm, good survival rate of plantings is also observed in the autumn: before the onset of frost, the plants manage to restore part of the active root system and can withstand the drying effects of wind and frost. In areas with harsh winters, fall planting should be avoided.

In any case, it is better to plant coniferous trees in the spring.

Spring planting is carried out as early as possible in the period before sowing grain crops for 5-7 days and must be completed before the buds open.

The establishment of forest belts is carried out by planting seedlings or saplings and, in some cases, cuttings (poplars, willows).

Seedlings of tree and shrub species, usually 1-2 years old, with a well-developed fibrous root system at least 25-27 cm long, are dug out from the nursery in the fall and spring, coniferous species - pine and larch - preferably in the spring. Seedlings plowed up with a digging bracket are selected from the soil, sorted, tied into bunches of 100 pieces, temporarily buried or transported to the planting site. When transporting, the roots of the seedlings are layered with wet straw or sawdust, and then covered with straw or a tarpaulin on top.

Forest strips should be created by planting cuttings in exceptional cases - under irrigated conditions, in depressions or in well-moistened soil. To do this, cuttings are cut 25-27 cm long with an upper cut diameter of 0.5-1.0 cm with well-developed buds.

In some cases, protective forest plantations are created by planting seedlings, i.e. large-sized planting material 3-5 years old, 1.5-3.0 m high. Poplar, birch, elm, ash, maple, linden seedlings are usually used.

Maintenance of forest strips. An important condition for successful afforestation in steppe areas is loosening the soil and destroying weeds in young plantings. If careful care is not taken care of, the soil becomes compacted, weeds grow quickly, suck out soil moisture, and young plants can quickly die. It is especially important to combat weeds in the first years of plant life, when the planted seedlings and saplings are separated, are in a unique microclimate and are not able to compete with weeds.

Agrotechnical care of forest belts includes mechanized cultivation of row spacing, weeding in rows and plowing of edges. Cultivators and flat cutters are used to cultivate row spacing. The edges are plowed with plows.

The timing and number of treatments are determined depending on the condition of the soil and the intensity of weed growth. In the first year, row spacing is treated 4-5 times, in the second year – 3-4 times, in the third and fourth years – 2-3 times. In subsequent years, throughout the life of the plantings, the row spacing is treated at least 1-2 times annually. The depth of tillage is 8-10 cm. The edges of the strips are plowed twice a year - in summer and autumn. Plowing depth is 18-22 cm.

With timely and good care, woody plants grow quickly and close their crowns. A forest plantation is formed. Closed forest belts are excluded from the arable land area and transferred to forest land.

In order to maintain shelterbelt forest belts in a ventilated and open-ventilated condition, special care measures are carried out in them - removal of lower branches, thinning of plantings, removal of underdeveloped, shriveled, diseased and damaged trees, as well as overgrowth.

Pruning of the lower branches begins 3-4 years after planting and is repeated after 2-3 years. First, they are pruned to a height of up to 1 meter, and then the crown is raised to 2 meters. The branches are removed with sharp pruners and a hacksaw. It is better to do pruning in the summer in dry weather and remove the removed branches from the field immediately.

Thinning of plantings begins at the age of 5-6 years, and subsequently is carried out as necessary. It is better to carry out this work in the fall. Depending on the density of the plantings, from 25 to 50% of the trees are removed for the first time. In all cases, trees are removed evenly over the entire area. Underdeveloped, withered, diseased and damaged woody plants are removed annually in spring and autumn.

Inventory and addition of forest strips. After forest planting work, usually not all planted plants take root. Some of them die off in the first year after planting. The reasons for the death of planted plants can be poor soil preparation, poor-quality planting material, untimely agrotechnical care, etc.

An inventory or recording of the area of ​​created strips and the survival rate of plantings is carried out annually at the end of the growing season, and of closed plantings - periodically.

Taking into account the survival rate begins with a general inspection of the plantings in nature. In the case of great heterogeneity in the survival rate of plants in the area of ​​forest belts, relatively characteristic areas are identified by eye, the boundaries of which are plotted on a schematic map of forest belts. Within each plot, trial plots are laid out to accurately record the survival rate of plants. In areas of forest belts up to 3 hectares, the size of the trial plot should be 5%, in areas of 4-5 hectares - 4%, from 6 to 10 hectares - 3% and over 10 hectares - 2%. A complete count of surviving and dead plants is carried out on the trial plot. Moreover, a trial plot is laid out across the entire width of the forest belt.

For each forest strip, an inventory list is compiled and the average percentage of plant survival for each homogeneous area is calculated. Depending on this, they plan and carry out additional plantings, i.e. planting plants in waste areas. Survival rate is considered high when 85-90% of plantings contain living plants. In this case, no additional plantings are made. If the mortality is over 50% of the number of plantings, then such forest belts are not supplemented; they are considered dead, plowed up and replanted. Planting is usually supplemented by hand using a shovel with high-quality planting material.

Cultural indicators	Optimal values
Overmoistening of the arable layer during the growing season, days.	Absent or for perennial grasses - no more than 20, grains - no more than 3
Topsoil thickness
Surface evenness	Closed microdepressions and microhighs on a segment of 5m - no more than 5cm.
Density of topsoil layer, g/cm 3	For spring grains – 1.1–1.3; annual grasses – 1.0–1.3; beets and potatoes – 1.0–1.2; perennial grasses –1.1–1.25
Soil moisture in the 0–50 cm layer, % of PV	50–70 – for grains, 55–75 – for perennial grasses, 55–70 – for root crops and industrial crops
Structurality coefficient
Nitrogen (NO 3 + NH 4) mg/kg soil.
Mobile phosphorus according to Kirsanov, mg/kg soil
Exchangeable potassium, mg/kg soil
Exchangeable base, mEq/kg soil	At least 150–200, no mobile aluminum

These indicators are dynamic in nature, which is associated with weather conditions, the degree of moisture and soil cover, and the way the land is used.

Thickness of the topsoil layer. The main task when creating a deep, uniform arable layer is to improve its physical properties and increase the effective fertility of the soil.

Research by scientific institutions and the experience of farms in creating and cultivating mineral soils of various granulometric compositions confirm that the deeper the arable layer, the higher and more stable the yields. An arable layer of 30–40 cm can absorb and retain 30–50% of melt water and completely rainfall – 50–60 mm without waterlogging. With an increase in the thickness of the arable layer by only one centimeter, the mass increases by 120–130 t/ha with an increase in organic matter up to three tons. During deep processing, moisture penetrates faster and more into the underlying layers, the temperature of the loosened layer increases, and gas exchange occurs better. On heavy soddy-podzolic gleyic soils with deep cultivation, the optimal air content in the spring was established 20–22 days earlier compared to conventional plowing, which is especially important for winter crops. Loosening the subsoil layer promotes greater release of carbon dioxide. With an increase in the thickness of the arable layer by one centimeter, the volume of total porosity increases by 50–55 m 3 /ha.

A thick cultivated arable layer has great irrigation and drainage value. With an increase in the filtration coefficient and moisture capacity of the soil, the volume of runoff is reduced and thereby increases the effect of drainage systems and reduces the removal of nutrients. Increasing the thickness of the arable layer from 15–20 to 25–30 cm, the filtration coefficient on loamy soils increases from 1.0–1.5 to 2.0–3.0, and on clay soils – from 0.5 to 2–3 meters per day. In a thick arable layer, more favorable conditions are created for the development of microorganisms and the root system of field crops. Weed seeds planted at great depths germinate slowly, and a significant part of them die. When the roots of weeds are deeply pruned, they die off faster. Deep incorporation of crop residues with good formation coverage eliminates the possibility of pests and diseases appearing on the subsequent crop.

Plants react differently to the depth of the arable layer and the depth of the main cultivation. Beets, corn, potatoes, alfalfa and clover, vetch, broad beans, and vegetable crops respond well to deep basic tillage. Winter grains, peas, barley, oats, buckwheat are crops that are moderately responsive to deep processing. Those that respond poorly or do not respond at all to non-deep processing include flax, spring wheat, and lupine.

In connection with the special importance of deep cultivation of the arable layer, methods for deepening and cultivating the arable layer have been developed. Reclamation plowing with intensive cultivation of podzolic soils can create a homogeneous arable layer with a depth of about 30 cm. At the same time, this technique, and especially plantation plowing, requires a lot of time and expense. The illuvial horizon raised to the surface is water-resistant only when wet. After repeated drying and wetting by precipitation, its structure is destroyed, structureless floating clay is formed and, when dried, becomes covered with a crust, which worsens soil conditions.

The use of two- or three-tier plowing, as a method of radically altering the profile, makes it impossible to create an arable layer of uniform fertility. Due to the high costs of longline plowing, it is unlikely that this technique can be applied on a large scale.

The deepening of the arable horizon by gradually plowing the lower layer towards the arable layer is noticeably manifested against the background of the application of sufficiently high doses of fertilizers and lime. It is better to deepen the topsoil during autumn plowing for crops that are responsive to deepening. The plowed podzolized part of the horizon should be mixed with the arable one in the spring, plowing up to 16 cm with the addition of organic matter.

Improvement of the soil profile of shallow peatlands is carried out using standard plowing combined with the formation of loosened strips under the plowed horizon. This ensures decompaction of the plow sole, the water-retaining layer and creates temporary cracks and wormholes.

The technology for creating a powerful arable layer of heavy soils that is uniform in terms of fertility consists of a system of layer-by-layer plowing with the elimination of the podzolic horizon. It involves the use of plant residues that serve bioreclamation a layer to regulate the water regime, using reclamation and conventional plowing, loosening, disking, and surface leveling.

Each of the above methods has both positive and negative sides. When designing intake systems to create a thick topsoil, it depends entirely on the type of soil.

General physical properties of soil.Soil solid density(specific gravity) – the ratio of the mass of its solid phase to the mass of water in the same volume at +4 0 C. The value is constant. Its value varies depending on the amount of humus and the composition of the mineral part of the soil. For soddy-podzolic soils of the republic, this indicator ranges from 2.40 to 2.65 g/cm 3 for peat-bog soils - from 0.5 to 1.4 g/cm 3 .

Density soil (volumetric mass) - the mass of a unit volume of absolutely dry soil taken in its natural composition, expressed in g/cm 3 . Density affects soil regimes and is a variable value, both in the process of soil cultivation and over the seasonal period. After loosening, the density of the soil decreases, then under the influence of precipitation and its weight it increases and reaches an equilibrium density. The best conditions for crops in terms of density occur when the values ​​of the optimal and equilibrium densities coincide.

Increased density negatively affects the water regime, gas exchange and biological activity of the soil. Excessive density reduces the field germination of seeds, reduces the depth of root penetration and their shape. The growth of the root system at a soil density of 1.4–1.55 g/cm 3 is difficult; more than 1.60 g/cm 3 is impossible. A very loose build is also unfavorable.

The topsoil layer is considered loose at a density of 1.15, dense at 1.15–1.35, and very dense at a density above 1.35 g/cm3. Field crops respond differently to soil compaction. Potatoes, fodder root crops, sugar and table beets grow well and produce high yields only on loose soils. The ratio of perennial grasses to soil density depends on the age of the plants. Young plants of legumes and cereal grasses, especially red clover, do not tolerate compaction of the topsoil very well. In the second and subsequent years of life, they can grow on relatively compacted soil. The density of the subsoil horizon also affects plant growth.

The optimal values ​​of volumetric mass on light loamy soils for crop rotation crops are 1.15–1.25 for barley, 1.20–1.30 for winter rye, 1.15–1.25 for oats, 1.02–1.30 for broad beans , potatoes 1.00–1.20, corn 1.10–1.40 g/cm 3 .

Soil porosity (porosity). The spaces between the soil lumps that make up the solid phase of the soil are called pores. The total pore volume as a percentage of the total soil volume is called porosity or duty cycle soil. Distinguish non-capillary and capillary porosity. Due to non-capillary pores, water permeability and air exchange occur. Capillary pores determine the supply of moisture available to plants. If the non-capillary porosity is less than 50%, then air exchange sharply decreases; if it is above 65%, the water-holding capacity of the soil decreases.

The ratio of volumes occupied by the soil solid phase and different types of pores is called structure of the arable layer soil. The optimal ratio of the volume of the solid phase of the soil and the total porosity for soils with a heavy granulometric composition is 40–35 and 60–65%, and for soils with a light granulometric composition, the solid phase of the soil is 50–55% and 45–50% of the total porosity.

The structure of the soil is regulated by improving the structure and tillage. Treatment methods increase overall porosity, increasing the volume of non-capillary pores, which improves the water-air regime of the soil. However, excessive soil looseness leads to loss of moisture and rapid mineralization of organic matter. It becomes difficult to plant small-seeded crops that require shallow planting of seeds - flax, clover, vegetables, millet, perennial grasses, so I compact the soil with rollers.

Soil structure. The main factor determining the composition of soils of medium and heavy granulometric composition and its stability over time is a mechanically strong and water-resistant structure.

The ability of soil to break down into aggregates is called structure. A set of aggregates of various sizes, shapes and qualitative composition is called soil structure. Depending on the diameter of the particles, a blocky structure is distinguished - lumps more than 10 mm, macrostructure - from 0.25 to 10 mm, microstructure - less than 0.25 mm. The most common forms of aggregates are granular, lumpy, blocky, and dusty structures. In agronomic terms, the most valuable for arable land is granular and lumpy with an aggregate diameter of 0.25 to 10 mm.

Structural soils have developed capillary pores that absorb moisture, and the spaces between them are filled with air. This enhances the development of plant roots and the work of microorganisms to decompose organic matter into nitrogen and ash nutrition. Structural soils do not float, have low surface runoff, and do not require much effort to cultivate. Evaporation from structural soil occurs slowly due to the wide spaces between the lumps, and hence the water reserve.

In structureless soil, moisture is absorbed slowly, and a significant part of it is lost due to surface runoff. The surface of structureless soil floats when moistened, and when it dries, it becomes compacted, forming a crust; gas exchange between the soil and atmospheric air is disrupted.

An agronomically valuable structure is characterized by such indicators as particle size, water resistance and aggregate quality.

Water resistance structure is called its ability to resist the erosive action of water. Soils with a high water stability of the structure for a long time retain the favorable composition achieved by the first treatment. Experiments have shown that the arable layer has a stable composition if it contains at least 40–45% of water-resistant aggregates larger than 0.25 mm. With a lower content of water-resistant aggregates, the soil quickly becomes compacted under the influence of precipitation. Structural soil has a loose composition, lower density and high porosity, more than 45%, the size of aggregates is 0.25–10 mm, capillary spaces predominate inside the lumps, and large non-capillary spaces between the lumps. Even with abundant moisture in structural soil, air is retained in the pores between the units; plant roots and aerobic microorganisms do not feel its lack.

The soil structure is destroyed mainly under the influence of mechanical, physico-chemical and biological factors. Mechanical destruction of the structure occurs in the uppermost layers and is caused mainly by tillage machines; physical and chemical destruction can be caused by monovalent cations entering the soil with precipitation and fertilizers; biological reasons for the destruction of the structure are associated with microbiological processes in which humus decomposes in aggregates and their destruction.

To create an agronomically valuable structure and maintain it in a water-resistant state, various agrotechnical techniques are used - sowing many summer grasses, applying organic fertilizers and liming, draining waterlogged soils, and methods of soil cultivation.

Cultivated crops also have a certain effect on the structure of the soil; for example, in the third year of barley monoculture, the coefficient of structure of the arable layer was 1.57, timothy – 1.54 and fodder beet – 1.10. The higher the total mass of roots per unit volume, the more strongly it influences the division of a continuous soil into macrostructural units, the actions of which can be compared to the function of wedges. Thus, perennial grasses significantly affect the soil only when the hay yield is 40–50 c/ha and higher, since the mass of the roots left is proportional to (or equal to) the mass of the above-ground part. The nature of the accumulation of root mass is greatly influenced by the depth of application of fertilizers and methods of soil cultivation. Humic substances, especially freshly formed ones, having a gluing ability, have a great influence on the formation of an agronomically valuable cohesive, water-resistant and porous soil structure.

Physico-mechanical properties of soil.Plastic– the ability of soil to maintain its shape under the influence of external forces. It appears when there is heavy moisture, especially on clay soils.

Connectivity– the ability of the soil to withstand forces directed at it. Sandy and structural soils have low cohesion. Humus in heavy loamy and clayey soils reduces their cohesion, while in light sandy soils it slightly increases it.

Swelling– an increase in soil volume when moistened, and shrinkage– reduction in soil volume upon drying. Sandy soils do not swell, clayey and loamy soils to a large extent. When these volumes change, the soil surface cracks, moisture is lost, and the root system of plants may rupture.

Ripeness. The condition of the soil is suitable for cultivation, i.e. when the cohesion is low and the soil does not stick to the implements, it crumbles well.

Hardness- this is the resistance of the soil to the penetration of a solid body into it to a certain depth. High hardness is a sign of poor physical, chemical and agrophysical properties.

Resistivity– this is the effort spent on cutting the layer, rotation and friction on the working surface of the tool, kg/cm 2. Based on the soil resistivity, they are divided into:

– light with a resistivity of 0.2–0.35 kg/cm 2 these are sandy, sandy loam and some peat;

– loamy with a resistivity of 0.35–0.55 kg/cm2;

– heavy soils (clayey) have a resistivity of 0.55–0.80 kg/cm2.

Table 2.2. Influence of soil mechanical composition on resistivity

The mineralization process is a complex of physicochemical and biochemical redox microprocesses leading to the complete decomposition of organic residues and humic substances themselves to the final oxidation products - oxides and salts. This process is obligatory and necessary in the carbon biocycle cycle, since it determines the release and transition into an accessible form of the main elements of plant mineral nutrition.
It is necessary to distinguish between: 1) direct and relatively rapid mineralization of plant residues without noticeable humification; 2) mineralization of already formed humic substances.
In reality, both processes occur simultaneously in any soil, but their ratio varies depending on specific conditions. Thus, in peat and peaty soils, the mineralization of plant residues is weakly expressed, and the mineralization of humic substances is practically absent. In the steppes, litter arriving on the soil surface is mineralized quickly, while humus substances, being fixed in the soil profile, are mineralized extremely slowly. Automorphic soils of the tropics are characterized by high rates of mineralization not only of incoming litter, but also of newly formed humus.
Mineralization processes do not form signs in the solid phase of the soil, so the speed of their occurrence can be judged by soil respiration, which is the total result of mineralization of both plant residues and humus. The highest intensity of CO2 emission from the soil surface is characteristic of tropical rainforests, which is due to the large mass of litter and its rapid mineralization. The lowest rates of soil respiration (less than 0.1 g CO2/m2 per hour) are characteristic of swamp and desert ecosystems. In plant communities of mid-latitudes, significant fluctuations in soil respiration rates were noted - from 0.1 to 9.5 g CO2/m2 per hour, associated with different soil activities in different ecosystems.
Another method for studying mineralization is to observe the kinetics of processes using labeled atoms. It allows you to directly study not only the intensity of the processes of mineralization of plant residues and humus, but also individual groups of compounds. Based on radiocarbon dating data, we calculated the mineralization coefficients of humus and humic acids in chernozem.

As can be seen from the data in table. 3, humic acids are the most resistant to mineralization. Moreover, the rate of their mineralization is different in different parts of the profile and naturally decreases with depth, as the activity of microorganisms weakens. The values ​​of mineralization coefficients are minimal in chernozem soils; in forest soils of the boreal zone they can reach 2.2%/year, and in tropical forest soils they can be even higher.