The main tasks of biological reclamation are the resumption of the process of soil formation, increasing the self-cleaning capacity of the soil and the reproduction of biocenoses. The biological stage ends with the formation of a cultural landscape on disturbed lands.

Organizational biological reclamation is carried out in two stages. On the first one, pioneer (preliminary, avant-garde) crops are grown, which are able to adapt to existing conditions and have a high regenerative capacity. On the second pass to the intended use. Lands contaminated with heavy metals, organic substances or industrial products are cleaned at the first stage using sorbents, plants or microorganisms (biodestructors), and then included in economic use under strict control by sanitary and epidemiological services.

Biological reclamation of lands contaminated with oil and oil products

During the period of intensive development of industry and transport, the production and use of petroleum products increased. Petroleum products are transported over long distances.

Oil products enter the soil, natural waters, polluting them. Currently, up to 1.5% of the volume of oil produced is lost. These losses end up in soils, rivers and other water bodies, leading to their pollution. Soil contamination with oil products often reaches 10 kg/m2 (with MPC = 0.1 mg/kg of soil), and in water bodies - up to 20 mg/l (with MPC = 0.05 mg/l). When the content of oil products in the soil is about 300 mg/kg, it becomes a substrate on which the biota is either oppressed or dies.

The spill of crude oil leads to the formation of bituminous solonchaks on the soil surface, to cementation of the soil surface, their tar formation, and takyrization.

Oil and oil products cause alkalization of soils, their alkalinization, and the death of soil mesofauna.

Soil pollution with crude oil and oil products occurs in the area of ​​oil fields, on the territories of oil storage facilities, at gas stations, as well as in the area manufacturing enterprises burning petroleum products. The latter emit a large amount of soot, sulfur compounds into the atmosphere, which eventually enter the soil and natural waters, polluting them.

The scope of work depends on the degree of contamination. With slight pollution, the activity of soil microorganisms in the destruction of hydrocarbons is activated. This includes loosening the soil, applying lime, gypsum, high doses of organic and mineral fertilizers, followed by plowing, creating a mulched surface from highly nutritious mixtures, sowing oil-tolerant plants with increased rates; possible options for the use of complex complexes: NPK + manure; NPK + lime; NPK + lime + manure. Resistant fodder plants are sown, the use of which must be strictly controlled, since they can accumulate carcinogens such as polycyclic aromatic hydrocarbons.

In case of severe pollution, engineering and environmental systems are constructed. The creation of such systems is due to the high mobility of oil products in the components of geosystems, especially with prolonged soil pollution, and the formation of large areas of free and bound oil products at the interface between the aeration zone and groundwater. Such anthropogenic deposits of oil products are formed near warehouses of fuel and lubricants, oil depots and oil refineries. They cause the danger of pollution not only of soils but also of underground and surface waters. Therefore, the tasks of the engineering-ecological system are the removal of mobile oil products, soil reclamation, protection of rivers and water intakes from oil pollution with simultaneous localization of pollution sources.

Loosening reduces oxygen deficiency and destroys the hydrophobic film of surface oil components, improves soil aeration. Liming or gypsum is used to neutralize soil acidity or alkalinity. With oil pollution, the amount of absorbed calcium and magnesium decreases, and the introduction of lime improves the agrochemical properties of soils and accelerates the decomposition of methane-naphthenic structures. On soils with a pH value of the salt extract less than 5.4, liming is carried out, and when the content of exchangeable sodium in the composition of the absorbing soil component is more than 10%, gypsum is required. The norms of lime and gypsum should be calculated according to the recommendations of agrochemical services.

To increase the activity of natural microflora, mineral and organic fertilizers are applied to the soil. For example, peat is the most accessible substrate, the reserves of which are quite large, and the extraction costs are relatively low. It is advisable to add nitrogen and phosphorus to peat in the form of fertilizers.

Liquid recultivants (whey, yeast mash) are also used, which are applied one month after the mechanical treatment of the territory. Watering the soil with whey is carried out at the rate of 5 l / m2. Then manure is applied using a spreader. Application rate 3-5kg/m2. After that, the manure is plowed with moldboard plows, loosened with a cultivator or harrowed. The treated soil is subjected to aging - 3 winter and 2 summer seasons - to give it its original state.

To obtain biological products, special bacteria, yeasts, and fungi are also used. Biomass of viable cells of hydrocarbon-oxidizing microorganisms with special physical and biochemical properties is obtained. Microorganisms utilize oil, create favorable conditions for the formation of humus-like organic compounds that affect soil fertility.

Oil-contaminated soils are treated with Acinetobacter sp., Alcalgenes sp., Pseudomonas sp., while solutions of phosphorus and ammonium salts are added. Oil products on the soil surface destroy the bacteria species Actinomycor elegans and Geotrichum marinum. Use of Actinebacter sp. gives an 80% deodorizing effect after 5 weeks. For the destruction of oil and oil products, strains of halotolerant and halophilic archaebacteria have been isolated. In conditions of high temperatures, bacteria of the species Bacillus albiaxialis can be used. A bacterium of the genus Desulfobacterium degrades salicylate under conditions of sulfate reduction. Streptomyces albiaxialis decomposes oil hydrocarbons with a salt content of up to 30%; efficiency at an optimum temperature of 28-30°C reaches 50%.

Figure 3 shows a block diagram of reclamation measures for oil-contaminated lands with the help of biological preparations.

Rice. 3 - Block diagram of reclamation activities

land reclamation landfill dump

The principle of organizing a system of biological soil treatment at the site of contamination (in situ) is shown in Fig.4.

Rice. 4 - Scheme of the process of cleaning the soil from oil products with the introduction of oil-oxidizing microorganisms

Table 2 shows the characteristics of some biological products used to clean up oil-contaminated lands.

Table 2 - Characteristics of some biopreparations of oil destructors

There are many more biological products designed to degrade oil. For example, the drug "Albit" is applied to the soil together with the sowing of grasses or after sowing at a concentration of 1.5-3.5 liters per hectare (working solution 100-300 l/ha). "Albit" for one growing season reduces soil pollution up to 10 times.

Firezyme non-toxic bioagent includes fermented enzymes and nutrients. Microorganisms multiply rapidly and decompose (eat) the oil slick and other contaminants to form carbon dioxide and water. Soil treatment is carried out with an aqueous solution by sprinkling (spraying) the soil surface. The amount of concentrate depends on the depth of oil impregnation of the soil. For example, to destroy an impregnation with a thickness of 5 cm, 50 g per 1 m2 is required, 200 cm - 200 g.

To clean up the contaminated site, the biopreparation "Mikromycet" of the company "Biolant" is used. Already a month after treatment with the drug, sporulation of fungi is noted, i.e. going on active work microorganisms. The advantage of the method is the absence of side effects from the impact on the environment.

The drug "Putidoil" consists of oil-oxidizing bacteria, mineral salts, nutrient medium residues. It is used for land reclamation and cleaning the surface of water bodies.

Biological products of the "Biodestructor" series, produced in Russia, are designed to eliminate pollution by oil and oil products, condensate and other organic compounds of soil (surface and lower layers), excavated soils, soil and Wastewater, as well as technological containers (surfaces of tanks, reservoirs). The biological product restores a single metabolic cycle by introducing massive amounts of microorganisms that decompose toxicants.

The drugs "Tornado", "Hera", "Valentis", "Leader", "MAG" are used, which decompose crude oil, gasoline, oils, animal fats, pesticides, dioxins.

To eliminate oil pollution of soils and surface waters, including watercourses, the bacterial preparations Devoroil (Institute of Microbiology of the Russian Academy of Sciences, Russia), Batsispecin (Novodex), Destroyle, Multis, Pete Sorb (England) are used. ) and etc.

For cleaning and reclamation of lands polluted with oil and oil products, CJSC "POLYINFORM" has developed and patented the complex biotechnology "SOILEX", which includes the consistent use of biological products for various purposes. The technology includes mechanical, chemical, sorption, microbiological and other methods for the removal and destruction of petroleum products.

Abroad, the "bio-remediation" technology, which is very effective, but expensive, is widely used for local treatment of heavily contaminated soils and other materials. The essence of this technology is that the contaminated material is loaded into a bioreactor equipped with steam extraction, pipelines for supplying oxygen (or air), nutrients, and pH and temperature control systems. Biological treatment can be combined with physical methods such as steam extraction or carbon adsorption to remove volatile compounds, or with chemical methods to remove toxic components or metals.

In the conditions of the city, when there are numerous small local oil spills, the direct use of biological products on the spot is irrational. In these cases, the most rational way is to collect contaminated soil or rock by cutting with their subsequent biological treatment at special sites.

Unfortunately, in Kazakhstan, until now, insufficient attention has been paid to such cleaning methods. And those few foreign biological products that are used are not effective enough, since they are developed for areas that differ sharply from the oil-producing regions of Kazakhstan in terms of climatic and environmental conditions.

The Institute of Microbiology and Virology set out to create domestic technologies that would be adapted specifically to our conditions. Which is not only natural, but more beneficial both economically and environmentally. Therefore, in recent years, we have been conducting scientific research on the creation and use of such biological products.

Researchers at the institute have already isolated and studied active strains of microorganisms capable of efficient utilization of oil and oil products. A unique collection of strains of such microorganisms adapted to soil and climatic conditions has been created oil fields Kazakhstan. Based on these studies, a series of biological preparations "Bakoil-KZ" was developed and introduced into production. The technology of their application has also been developed. RoK patents have already been obtained for strains, for production methods, for trademark. Certificates of origin of products and conformity of products were issued. The effectiveness of this domestic biological product has been proven at various fields in the Mangistau and Atyrau regions. In particular, it has been confirmed that they are capable of destroying up to 98% of the oil contained in the soil within one and a half to two months.

The Institute has already concluded contracts for the supply of a biological product with a number of companies to clean up more than 70 hectares of oil-contaminated soil in Western Kazakhstan. Domestic preparations, which has been proven by practice, can be used for post-treatment of soils in cases where other methods fail. Their use complies with all known world standards and promotes health improvement. environment.

There are also other biological products produced in Kazakhstan. One of these is Oil Destructor-KazBio, which has been produced in our country since 2011. This is a new highly effective biological preparation based on Rhodococcus erytropolis strain KD, designed to clean soils, soils, sludges, water surfaces from oil pollution. "Oil Destructor-KazBio" is a concentrate of live bacteria, ready for use without preliminary revitalization or activation, and has a high activity of oxidizing hydrocarbons of various classes.

"Neftedestruktor-KazBio" is actively working in the temperature range +5 - +400C. At negative temperatures, the microorganisms that make up the preparation do not die, and restore their activity when positive temperatures occur. In the case of treatment of an oil-contaminated area with a biological product before winter, in early spring, after the snow melts, the destruction of hydrocarbons immediately begins, which is visually fixed - the surface of the treated area becomes brown, and the surface of the area where the preparation was not used remains black.

The rate of application of the drug depends on the initial level of contamination, as well as on the conditions of the growing season. At an air temperature of +20°C and a humidification of 60-70% FPV, the decomposition of hydrocarbons to CO2 and H2O proceeds much more intensively, while the dose of the drug can be reduced. Under less favorable conditions (temperature fluctuations from +5 to +40 ° C, irregular moistening - drought, rains), the following norms are recommended, indicated in table 3.

Thus, by comparing several methods of reclamation of lands contaminated with oil and oil products, a number of advantages of biotechnology over other options can be identified:

environmentally friendly technology, as natural biological processes of vital activity of microorganisms are used;

it is more economical to use biopreparations, since their introduction into the soil does not require a large number which reduces the cost of their purchase;

takes a relatively small amount of time to restore the soil;

The Republic of Kazakhstan, having large oil reserves and, accordingly, no less problems from the consequences of oil production, develops various biological preparations of the aboriginal composition of microorganisms, thereby saving on the purchase of foreign preparations, since the cost of domestic ones is 4-5 times less. Our scientists are conducting intensive scientific research to search for oil-degrading strains and create biotechnologies based on their ability to use oil constituents as food sources.

Biological reclamation

(from lat. re - a prefix meaning repetition, and late lat. cultivo - I process, cultivate * a. biological reclamation; n. biologische Rekultivierung; f. remise en culture biology; and. recultivo biologico, reproduccion biologica) - land reclamation and agrotechnical measures to restore fertility and households. land values, carried out after technical reclamation. includes liming, plastering, washing, sanding, claying, and other techniques aimed at improving the chemical. and physical reclamation properties. layer. Agrotechnical methods provide for a system for processing and fertilizing the bulk layer or the layer of the urban settlement (recultivation layer), special. crop rotations, planting trees and shrubs, etc. Biol. the activity of the recultivated layer is increased with the help of microorganisms introduced from organic matter. fertilizers. Usually biol. the reclamation stage lasts from 4-6 to 10 years.
The composition and scope of work on B. p. is determined depending on the direction of reclamation (creation of agricultural land, forest plantations, decorative and landscaping complex), as well as on the properties of urban settlements that make up the surface of recultivated lands. In the USSR, B. r. is carried out on the basis of the reclamation project being developed (in conjunction with the mining project) design organizations min-in and departments operating deposits of p. and., with the involvement (on contractual terms) of the design organizations of the Ministry of Agriculture of the USSR, State. to-ta forest x-va of the USSR and the Ministry of Fisheries of the USSR. Projects for the creation of garden and park plantings in the disturbed area are included in the master plans for the development of settlements and suburban areas.
B. r. on lands intended for use in agriculture and forestry, it is carried out by land users (state farms, collective farms, forestry enterprises, etc.) at the expense of mining resources. enterprises working on these lands. On B. r. accounts for up to 25% (0.2-1.5 thousand rubles per 1 ha) of the total costs of mining. enterprises for the reclamation of disturbed lands. Costs for B. r. lands are attributed to the cost of produced p. and. (during the development of deposits), the cost of enterprises, buildings, structures (during the construction of these objects) or work (during geological exploration and other works). Literature: Motorina L. V., Ovchinnikov V. A., Industry and Lands, M., 1975; GOST 17.5.1.01-78. Protection of Nature. lands. Terms and Definitions. V. P. Kostovetsky.

Mountain Encyclopedia. - M.: Soviet Encyclopedia. Edited by E. A. Kozlovsky. 1984-1991 .

See what "Biological reclamation" is in other dictionaries:

biological reclamation- biologinis atkūrimas statusas T sritis ekologija ir aplinkotyra apibrėžtis Geotechninių ir fitomelioracinių priemonių visuma pažeistų žemių derlingumui atkurti, dirvožemiui apsaugoti nuo erozijos ir defliacijos. atitikmenys: engl. biological… … Ekologijos terminų aiskinamasis žodynas

Biological land reclamation- 16. Biological stage of land reclamation (biological land reclamation) stage of land reclamation, including measures to restore their fertility, carried out after technical reclamation ... Source: Order of the Ministry of Natural Resources of the Russian Federation N ... Official terminology

Biological stage of reclamation or biological reclamation- 7. Biological stage of reclamation or biological reclamation According to GOST 17.5.1.01 78 Source ...

biological stage of land reclamation (biological reclamation)- 3.5 biological stage of land reclamation (biological reclamation): The stage of land reclamation, which includes a set of agrotechnical and phytomeliorative measures to restore the fertility of disturbed lands. Source … Dictionary-reference book of terms of normative and technical documentation

Lands (from lat. re prefix, meaning renewal, and cp. century. lat. cultivo I process, cultivate * a. land reclamation; n. Bodenrekultivierung, Bodenwiederurbarmachen; f. remise en etat des sols, rehabilitation des sols; i. ... ... Geological Encyclopedia

Organizational, technical and biological measures aimed at restoring the suitability of land for use for its intended purpose. Technical reclamation differs (leveling the surface or performing other land ... ... Glossary of business terms- a set of measures aimed at restoring the economic, biomedical and aesthetic value of disturbed landscapes. There are 2 stages in landscape reclamation: technical (technical reclamation) land preparation for ... ... Ecological dictionary

biological reclamation- Land reclamation, aimed at intensive increase in the fertility of disturbed lands, productivity of agricultural and forest crops through the application of a system of agrotechnical and hydro-reclamation measures. Note To the main events for ... ... Technical Translator's Handbook

Mining and technical stage of land reclamation

Reclamation of disturbed lands

Reclamation- a set of works on the ecological and economic restoration of lands and water bodies, the fertility of which as a result of human activity decreased significantly. The purpose of reclamation is to improve environmental conditions, restore the productivity of disturbed lands and water bodies.

Causes of disturbed lands and water bodies

Types of human activities, as a result of which there may be a need for reclamation of lands and water bodies:

§ economic activity;

§ mining, especially open pit mining;

§ deforestation;

§ occurrence of landfills;

§ construction of cities;

§ creation of hydraulic structures and similar facilities;

§ carrying out military tests, including tests of nuclear weapons.

Two main stages of reclamation

Reclamation works usually have two main stages - technical and biological. At the technical stage, the landscape is being adjusted (filling ditches, trenches, pits, depressions, soil failures, leveling and terracing industrial waste heaps), hydraulic and reclamation structures are being created, toxic waste is being buried, and a fertile soil layer is being applied. At the biological stage, agrotechnical work is carried out, the purpose of which is to improve the properties of the soil.

Areas of land reclamation

Depending on the goals that are set during land reclamation, the following areas of land reclamation are distinguished:

§ environmental direction;

§ recreational direction;

§ agricultural direction;

§ crop production;

§ hay and pasture direction;

§ forestry direction;

§ water management direction.

The mining and technical stage begins with the removal and rolling of the fertile layer (if it is not disturbed). The thickness of such a layer is determined by the soil map, and in its absence - by soil scientists by conducting special studies. The soil layer, as a rule, is removed by a bulldozer or grader and placed in heaps (cavaliers), which are stored until the completion of construction work on the site. So that the soil in the piles is not washed away by water or blown up by the wind during storage, it is recommended to sow the piles with herbs, either clover or alfalfa. If the removed land is used on the site, then after the completion of construction it is spent on the planning of the territory in accordance with the project. In some cases, the removed soil is used to level low places, backfill pits, pits. Then, a soil layer rich in organic matter is applied to the leveled surface. If the territory is used for mining building materials, for example, limestone, stone, granite, then after removing and storing the soil layer, they begin to produce overburden rocks, from which dumps are also formed. At the same time, toxic rocks are stored separately from good land. The order of work is determined by the reclamation project.

The biological stage consists in restoring the fertility of disturbed lands, creating and increasing the humus layer of soils by sowing grasses, shrubs and trees; cultivation of agricultural crops is allowed. In the latter case, it is necessary to follow a certain sequence: first, cultivate low-demanding crops with a large plant mass, and after restoring soil fertility, move on to other crops based on the accepted agricultural technology for their cultivation. At the first stages of reclamation works of the biological stage, as a rule, afforestation prevails, and tree species are selected in accordance with acid-base properties, mechanical composition and other features of soils and soil-forming rocks. Restoration of territories is carried out according to various directions intended use:

For the needs of agricultural production (agriculture, gardening, etc.);

For afforestation, including industrial forestry;

In order to create reservoirs for various purposes (fish farming, water supply, recreational areas, etc.);

For housing and industrial construction, etc.

Many factors influence the success of recultivation:

Petrographic and chemical composition of rocks stored in dumps, acid-base characteristics of surface, ground and underground waters filtered through them;

The presence of admixtures of chemical elements in the form of independent minerals or other forms capable of transforming into water-soluble compounds (salts) with subsequent accumulation in soils and vegetation and often representing toxic substances (mercury, cadmium, selenium, arsenic and many other elements);

Forms of dumps, steepness of slopes, etc.

In simple terms, reclamation is a set of measures to restore the natural properties of the land and its fertility. How is it carried out?

The flow of the process and its stages

This procedure is a whole combination of activities and operations that are closely interconnected and the effectiveness of the previous one directly affects the effectiveness of the next one.

Experts distinguish two main phases of this process - technical and biological land reclamation:

• technical - consists in the implementation of a set of procedures aimed at updating the earth's landscape. At this step, all waste is buried;
• biological - consists of several interrelated agrotechnical works, the main task of which is to increase the fertility rate, as well as all benign and structural indicators of the land cover. Quite good results at this stage can be achieved using the method of sowing legumes or black poplar, which enrich it with nitrogen. The planting of young loess plantations on the site of cut forests is also relevant.

The purpose of the reclamation

All of the above types and many others eventually inevitably lead to the fact that the structure of the soil and its structure are significantly disturbed, the hydrological regime of the relief of a given area changes, leads to the formation of man-made landforms and other changes and disturbances. In order to return the original structure and quality environment to the lands and carry out land reclamation.

The project of reclamation of agricultural land aims to make it possible to further use the reclaimed soils for the performance of effective agricultural work, the creation of the most suitable conditions for life and productive human activity, the return of the original structure to the exploited turf and chemical composition, a complete renewal of the ecological system.

What varieties exist?

Technical and biological reclamation, according to the methods of their implementation, as well as the further operation of reclaimed sites, includes the following areas:

• forestry - consists in the formation of forest reserves, planting plantations to protect fields and forests, etc.;
• agricultural - aimed at creating perennial pastures and arable lands, hayfields and garden areas;
• water management - such a course involves the formation of various reservoirs;
• recreational - the main goal is the design of recreation areas and recreation centers, recreational reservoirs and sports facilities;
• construction - construction of civil and industrial facilities.

To date, the condition of the sites is such that the implementation of the renewal is impossible in any one direction. It is necessary to use several options that will be closely interconnected with each other. Only coordinated and clear work can lead to positive results.

Factors that are taken into account when choosing a technical reclamation method

The choice of one or more methods, the following points are of decisive importance:

• features of natural conditions;
• geographical location of the territory;
• technical specifications for land reclamation;
• prospective operation of the renovated area;
• deadlines;
• chemical, benign and structural composition of disturbed virgin soil, etc.

Feature and variations of the technical type

If we talk about this step, I would like to dwell in more detail on its varieties:

• design - structural - the essence lies in the development of projects for the formation of new landscapes and surfaces. To do this, they practice such means as profiling, terracing, planning in the vertical direction, planting new woody and herbaceous plants, etc.
• chemical - here they use a variety of chemical substances (lime, gypsum, clay, sorbents, mineral fertilizers, etc.), which, acting on the soil surface, contribute to the restoration of its properties and parameters;
• hydrotechnical - technical stage of reclamation of disturbed lands, which is carried out with resort to hydraulic engineering, differs in that the soil is rid of excess moisture and water by irrigation or reclamation. In addition, the change in the frequency of soil flooding by surface waters is also of no small importance;
• thermotechnical - they use technologies such as heating and warming the surface, by mulching or grading it.

The technical stage of reclamation is practiced using any one or a set of measures that give a positive outcome. This is influenced by certain geographical and geological reasons inherent in a particular area.

Characteristics of the biological type

Biological land reclamation represents one of the stages of restoration of damaged territories. If we talk about damaged, then they include those on which there is a violation, destruction or complete destruction of natural components (plants and wildlife, soils, hydrological objects, relief).

She sets herself the following goals:

• full or partial renewal of soil-forming processes;
• increasing the self-cleaning capacity of the earth;
• normalization of the natural biosphere.

What affects the cost?

The biological reclamation project contains detailed calculations of the price of such a procedure. The cost of biological reclamation depends on such factors:

• location and technical condition of aquifers;
• the possibility of the beginning of swamping of the area;
• the presence, quantity and quality of toxicological substances;
• location of the site in relation to settlements or other plots;
• zoning factor.

The budget documentation includes:

• information on the cost part;
• local estimates;
• estimated cost of services;
• price calculation necessary materials as well as transport costs.

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The main tasks of biological reclamation are the resumption of the process of soil formation, increasing the self-cleaning capacity of the soil and the reproduction of biocenoses. The biological stage ends with the formation of a cultural landscape on disturbed lands.

Organizational biological reclamation is carried out in two stages. At the first one, pioneer (preliminary, avant-garde) crops are grown, which are able to adapt to existing conditions and have a high regenerative capacity. On the second - go to the intended use. Lands contaminated with heavy metals, organic substances or products of industrial processing are cleaned at the first stage using sorbents, plants or microorganisms (biodestructors), and then included in economic use under strict control by sanitary and epidemiological services.

To develop effective methods of biological reclamation, it is of great importance to study the processes of evolution of vegetation cover in various natural zones and technogenic conditions.

The formation of vegetation cover on overburden dumps is very slow due to the complex time-varying topography of the dump surface, the poverty of rocks in nutrients, and the instability of water and thermal regimes. The duration of the natural formation of vegetation cover in the forest and forest-steppe zone is characterized by three periods:

In the first 5–6 years from the beginning of the formation of disturbed lands, a mosaic open vegetation cover appears, consisting of plants with a wide range of tolerance;

In the next 5…6 years, a multi-species plant community (30…40 species) is formed, in which zonal features are noticeably manifested and a multi-tiered structure of biocenoses is formed;

After 10–12 years, differentiation of the species composition begins to prevail, dominance passes to perennials, a stable vegetation cover with a pronounced layering is created, and seasonal dynamics is well traced.

Under difficult conditions, the terms of formation of the vegetation cover increase significantly, for example: on the dumps of the Moscow brown coal basin with a large proportion of sulfide-containing rocks, by the age of 20, the vegetation cover is still at the beginning of the second period.

On sand quarries in the steppe zone, vegetation appears after 5 ... 7 years, by 10 ... 12 years it can include 5 ...

On gravel pits, individual plants are visible for 3-4 years. The first of them to settle coltsfoot, wormwood. By the age of 5…6, there are already 8…10 types of herbs: sheep’s fescue, hairy hawkweed, cat’s foot, etc. By the age of 15, there are about 30 species: sleep-grass, common yarrow, field clover, team hedgehog, meadow bluegrass; from trees and shrubs: Scotch pine, willow.

In developed peat quarries, with sufficient moisture and nutrients, vegetation appears already in the first year. At first, rare plants appear: coltsfoot, fescue, green moss, nettle, sedge. After 2 ... 3 years, a continuous grass cover is formed: fescue, nettle, sedge, succession, reed, horsetail, rush, goose foot, oxalis. After 5 ... 6 years, trees and shrubs settle: black alder, willow, viburnum, vine, gray alder, maple, birch, aspen, poplar.

Overgrowing of disturbed lands creates a reserve in young soils organic matter, which, as a result of biochemical processes, improves the nutrient regime of these soils and contributes to the formation of a stable vegetation cover.

The rate of soil formation and the formation of soil horizons depend on the properties of soil-forming rocks, their water and thermal regimes, relief, natural and climatic conditions of a given area, on the species composition of vegetation and the duration of natural land restoration.

Dumps and mounds of overburden rocks grow faster on the northern and northwestern sides, since stable water and thermal regimes are observed here. The southern slopes, which experience the greatest temperature fluctuations and significant erosion, are covered with vegetation only in the lower parts of the slope, where washed-out fine earth accumulates.

On 25-year-old loamy dumps of the Moscow region coal basin under forest cover, the rate of soil formation is 2.4 ... 3.6 mm/year, under grasses - 4 mm/year. In the same place, on young 9-year-old dumps under grasses - 6.7 mm/year. On sand dumps overgrown with grass, the rate of soil formation is close to the rate in the forest - 3.5 mm/year.

Intensive accumulation of humus on disturbed lands is observed in the period from 5 to 20 years, then the rate of soil formation decreases, which is due to the stability of biogeochemical processes under certain plant communities (Fig. 2). As a result of these processes, in specific climatic zones, young soils are formed that are close in genesis to zonal soils, but differ from modern soils for a number of reasons:

The process of soil formation is a very long process;

Disturbed lands have other soil-forming rocks in their genesis;

Soil formation factors have changed.

Therefore, on disturbed lands, especially in those places where the intended use is difficult due to organizational, technological, social and climatic conditions, it is necessary to strive, first of all, to stimulate the vegetation cover. For this purpose, you can use the timing certain types plants to certain types and properties of soils, soils and rocks. Such plants are identified in the course of botanical and species analysis of plant samples taken on disturbed lands, and can be recommended as pioneer (preliminary, avant-garde) crops.

The confinement of plants to overburden rocks of the Kursk magnetic anomaly (forest-steppe zone) is presented in Table 4.

On the 24-year-old dump of the Tishinsky deposit of polymetallic ores, backfilled with sericite-chlorite-quartz rocks, siltstones, porphyrites, there are white and yellow sweet clover, common bruise, Ivan-tea, mouse pea, highlander bird, wormwood ordinary and bitter, cocksfoot, rump awnless, fescue, ground reed grass, coltsfoot, etc., from tree-shrub species - warty birch, aspen, poplar, maple, wild rose, elderberry, etc.

To create a vegetation cover on lands contaminated with heavy metals, it is necessary to take into account the recommendations of Table 5, and if arsenic is present in the soil, it is advisable to cultivate wild rose.

Table 4. Species composition of plants associated with overburden dumps

Table 5. Species composition of plants confined to lands containing heavy metal salts in excess

With the help of plants, it is possible to determine the predominant content of individual metals in the soil. This property of plants for mining purposes began to be specially studied as early as the 17th century. In 1763 M.V. Lomonosov noted: “On the mountains in which ore and other minerals are born, growing trees are usually unhealthy, that is, their leaves are pale, and they themselves are low, crooked and dry up to their perfect old age, and the grass growing under the veins is usually smaller and paler."

On lands where technical reclamation is difficult, or their reuse is possible (for example: reuse of dumps containing rocks with a low concentration of rare metals), a vegetation cover is created by scattering pelleted seeds of grass mixtures and shrubs. Seeds of plants, taking into account their confinement to rocks, are scattered by plane in early spring, along with small doses of mineral fertilizers.

The ability of the plant to take root is used in the reclamation of dumps of non-toxic overburden without preliminary application of the soil layer. For this, a special technology of plant cultivation is being developed, for example:

Cultivation of legumes for 3…4 years with plowing to a depth of 25…30 cm;

Cultivation of a cereal-legume grass mixture with the introduction of a small dose of mineral fertilizers for 3 ... 4 years, followed by plowing of herbs to a depth of 20 ... 25 cm;

Sowing grasses (vetch-oat mixture, sweet clover) followed by plowing.

The use of this technology on the dumps of the Kursk magnetic anomaly made it possible to create a humus reserve of 1.5% in a layer of 0–20 cm and obtain a yield of rye and barley of about 20 c/ha. If disturbed lands are intended for agricultural use, then the general scope of biological reclamation work should be as follows:

Leveling the surface of the earth and applying a soil layer on it, especially on substrates containing unsuitable rocks (final works of technical reclamation);

Cultivation of pioneer crops (annual or perennial) to enhance the processes of soil formation;

The introduction of special crop rotations for the restoration and formation of the soil layer;

Application of conservation agriculture practices to improve soil fertility and resistance to erosion and deflation;

Soil monitoring by environmental and sanitary-epidemiological services.

To organize agricultural land on dumps containing marly clays, according to the recommendations of the Dnepropetrovsk Agricultural Institute, it is advisable to grow fodder peas as a pioneer crop, and then proceed to sowing spring crops, for example: barley.
In Germany, crop rotations containing about 70% of legumes are used on dumps of lignite dumps.

According to the research of the Department of Land Reclamation and Reclamation of Moscow State Unitary Enterprise, the cultivation of vetch-oat mixture on floodplain meadow soils contaminated with oil products accelerates the process of decomposition of hydrocarbons. As experience shows, the best pioneer crops for agricultural reclamation are legume and legume-cereal grass mixtures, which have a high phyto-cultivating ability compared to other plants.

In the formation of young soils during reclamation for forestry purposes, legumes, legume-grass grasses, shrubs and some tree species are used as pioneers. Of the tree and shrub vegetation, the most common as pioneers are: white acacia, narrow-leaved sucker, sea buckthorn, yellow acacia, golden currant, warty birch, willow, alder, poplar, bird cherry.

Reclamation of forestry purposes is carried out to create forest plantations on disturbed lands for industrial, protective, water-regulating, water-protective and recreational purposes. It begins with the selection of woody and shrubby plants in accordance with the suitability of disturbed lands for biological reclamation and based on natural and climatic conditions. For example, in the steppe zone, for the reclamation of dumps, embankments, quarry excavations, and the creation of protective forest belts, the following tree and shrub species are recommended: elm, ash-leaved maple, white locust, black poplar, red oak, pedunculate oak, yellow locust, golden currant, tamarix branchy , goof narrow-leaved.

The most effective method of biological reclamation on disturbed lands is the creation of a multi-species vegetation cover with the participation of perennial grasses and resistant species of shrubs and trees. With such a multi-tiered structure, disturbed lands are well protected from erosion and deflation, and thanks to leaf litter and root systems, they receive a large increase in organic matter.

On lands contaminated with man-made products, main task biological reclamation is to increase the self-cleaning capacity of the soil. The solution to this problem is possible with the help of the joint functioning of technical and biological systems operating with a wide range of measures, including the use of specially grown microorganisms.

Reclamation (cleaning) of soils from technogenic products with the help of microorganisms is based on the destruction (decomposition) of these products within a regulated time. In practice, this method is used to clean up soils contaminated with oil, oil products and pesticides. The technology of biodestruction includes the creation of favorable water-air, thermal and nutritional conditions for microorganisms and regular control of the population used. Therefore, the effectiveness of this type of reclamation depends on the controllability of regulatory factors and the quality of strains.