Types of Farming Systems

Slash-and-Burn and Forest-Field Farming Systems

The slash-and-burn farming system is a method of developing lands by burning natural forest vegetation. The freed area, after primitive surface cultivation, was used for crops of cultivated plants, for example, cereals or flax. It was widespread in the northern part of Russia when developing lands overgrown with forest.

Humans arrived at this method of land development as a result of observations: in areas (burned plots) after forest fires, lush natural herbaceous vegetation developed. Thanks to fertilization with ash, the soil was enriched with nutrients and helped neutralize the acidic reaction. Nitrogen was formed during the decomposition of forest litter, remains of herbaceous vegetation, and the activity of nitrogen-fixing microorganisms. This approach made it possible in the first two years to obtain good yields of cereal crops and flax. However, then the soil quickly lost its fertility, its physicochemical properties deteriorated, and microbiological processes were inhibited.

To extend the period of use of developed plots, areas were sometimes left without sowing for one or two years, and manure was applied if weakly developed animal husbandry allowed it. But these measures did not prevent a decrease in the yield of cultivated crops. When the yield fell to a very low level, the farmer left the developed plot and moved to another, while the former one again became overgrown with vegetation.

With the emergence of private ownership of land and as arable areas increased, there arose a need to return to plots that had previously been used for crops but had been abandoned and overgrown with forest. Thus the forest-field farming system appeared, partially replacing the slash-and-burn one.

The shifting-fallow and forest-field systems are usually assigned to the period of the slave-owning system.

Fallow and Shifting-Fallow Farming Systems

Fallow farming system — a method of developing virgin lands with high natural fertility, occupied by herbaceous steppe vegetation, which were plowed and sown with cereal plants, less often with oil flax or melons. To ensure the mobilization of nutrients and accumulate moisture, the newly plowed virgin land was left for some time for fallowing. However, repeated cultivation of cereal crops led to a gradual decrease in yield. For this reason, it became more profitable to leave the plot after use as fallow and develop a new virgin steppe plot. The plot left as fallow became overgrown with weeds, and after 15–20 years, after vegetation characteristic of virgin land appeared on it, it was plowed again and used for crops. Thus, the original fallow system evolved into the shifting-fallow one.

The shifting-fallow system directly grew out of the method of settling the steppes, out of the nomadic character of the peoples inhabiting them, out of the excess of land space compared with population, out of the unparalleled productivity of the steppe chernozem.

A. V. Sovetov

The main difference between the fallow and shifting-fallow systems is that in the fallow system they do not return to abandoned plowed plots. Whereas in the shifting-fallow system the land mass was divided into several plots, part of which were used for sowing cereal crops, and the rest, which had lost fertility, were left as fallow for 10–30 years. After natural restoration of fertility, the fallow lands were again cultivated and sown with cultivated plants.

The restoration of soil fertility occurred naturally with the help of various herbaceous vegetation. Thanks to the higher natural fertility of soils in the steppe zone and the role of perennial and other herbaceous vegetation in the reproduction of fertility, the period of its restoration was significantly shorter compared with forest vegetation. Crops on one plot were grown for 6–8, sometimes 10 years.

The fallow and shifting-fallow farming systems are characteristic of steppe regions, therefore they were widespread in a number of countries with steppe lands. In Russia they were widely distributed in the Chernozem zone, the Trans-Volga region, and less often in the south of Russia.

With the development of natural sciences, in particular the theory of plant nutrition, the scientific substantiation of these farming systems also changed. Under the dominance of the humus theory of nutrition, the restoration of soil fertility was explained by the influence of natural herbaceous vegetation on the accumulation of humus. With the creation of the theory of mineral plant nutrition, the decrease in cereal yields over a number of years after plowing virgin land was explained by the depletion of soil in phosphorus and other nutrients.

P. A. Kostychev, studying samples of virgin chernozem soils and old-arable lands, established the absence of a noticeable difference in their chemical compositions. Old-arable chernozem soils also contained a sufficient amount of humus, while virgin lands possessed a better soil structure. However, P. A. Kostychev did not consider the loss of structure to be the only cause of the decrease in cereal crop yields after plowing virgin land. The land had to be left fallow not because it was depleted, but because the plots became infested with weeds, which could not be controlled by ordinary cultivation. Therefore, it was much more profitable to move to a new plot.

Fallow System

Fallow system — a farming system that replaced the shifting-fallow and fallow systems, into which fallow fields were introduced.

The necessity of introducing fallow fields was justified by the struggle against weeds. Economic conditions forced a reduction in the fallow period and at the same time the duration of using plowed fallow for crops. For this reason, to suppress weeds and rationally use land, fallow soil cultivation began to be introduced between cereal crops. Thus, the shifting-fallow system turned into a transitional shifting-fallow form, and in a number of cases directly into the fallow one.

The emergence of the fallow farming system occurred during the period of feudalism. Population growth led to an increase in demand for agricultural products, which became the cause of expanding agricultural areas and reducing the periods of fallow use to 1–2 years.

The fallow system can be considered a more advanced farming system, since land use improved and grain production increased. The appearance of commercial grain in Russia is associated with the beginning of the use of the fallow system.

Soil cultivation in the fallow field in combination with the application of fertilizers, primarily manure, became human intervention in natural soil processes, which caused an increase in yield. Cereals in the fallow system account for up to 2/3 of the arable area, the remaining part is occupied by fallow fields.

The most common crop rotations of the fallow system were:

• two-field: 1 — fallow, 2 — cereals;
• three-field: 1 — fallow, 2, 3 — cereals;
• less often four-field: 1 — fallow, 2, 3, 4 — cereals.

A major disadvantage of the fallow system was the absence of fodder crops, which negatively affected animal husbandry. Plowing of fallow lands also led to a reduction in pastures. For grazing livestock in the spring-summer period, the fallow field was used, and in the summer-autumn period after harvesting cereals — the remaining fields. However, this approach did not provide animal husbandry with a sufficient amount of feed. The productivity of animal husbandry decreased just as the amount of manure did, which in turn negatively affected yield. Animal husbandry, having no solid basis, received the name manure-based.

Despite the progressiveness of the fallow system compared with the shifting-fallow and fallow systems, untimely cultivation of fallow and fields due to grazing livestock on them, poor soil cultivation, and constant cultivation of annual cereal plants led to weed infestation, decreased fertility, and deterioration of the physical properties of the soil. The low culture of farming led to the development of erosion in many regions, and yields remained rather low and unstable. For example, cereal yields were 0.5–0.7 t/ha; in dry years, even seeds were not harvested.

In the central regions of Russia, the fallow system appeared at the beginning of the 16th century, became widespread, and remained the main one until 1917. V. I. Lenin characterized the grain-fallow system of tsarist Russia as extremely conservative and subjected it to serious criticism, as it did not provide even the most elementary conditions for progress in agriculture.

Under the conditions of socialist agriculture, the grain-fallow farming system acquired a different significance. Thanks to good technical equipment, timely cultivation of fallow and other rotation fields, application of optimal amounts of fertilizers, and varietal sowings, the grain-fallow system showed its effectiveness. With three-field or four-field rotations under the application of soil-protective, forest-reclamation measures, and modern crop cultivation technologies, it is still used in a number of arid regions of Kazakhstan and Siberia, where, due to the special climatic, soil, and economic conditions, other farming systems are less effective.

In Western Europe, the fallow farming system has long not been used. It has been preserved only in grain farms of arid regions of the USA, Canada, and some other countries, where its use is economically justified.

Multi-Field Grass System

Multi-field grass, or pasture system — a farming system in which a limited part of the lands was allocated to cereals and other crops, and a larger part to perennial grasses. As the latter, natural grasses were first used, then sown for hay and livestock grazing for 4–6 years. It was widespread in some coastal and mountain regions of various countries. It became a result of the development of animal husbandry.

In connection with the dual character of the use of perennial grasses, A. S. Ermolov considered it correct to call this system not pasture but multi-field grass. Soil fertility in this system is maintained by natural factors, however, directed to a certain degree by humans through grass sowing and cultivation of fallow fields. An example of such a system is the Mecklenburg system, which originated in Germany in the middle of the 18th century as a development of the fallow system.

In regions with a more continental climate, the multi-field grass system showed lower effectiveness compared with the convertible and other systems with fodder crops.

In the Non-Chernozem zone, multi-field grass rotations received some application in combination with grain-fallow ones. Thus, on the farm of A. N. Engelhardt in Smolensk Oblast, a 15-field rotation was used:

• 1–6 — perennial grasses, 7 — flax, 8 — fallow, 9 — rye, 10 — spring crops, 11 — fallow, 12 — rye, 13 — spring crops, 14 — fallow, 15 — rye.

From 1871 to 1897, at the farm of the Petrovsky Academy (now the Moscow Agricultural Academy named after K. A. Timiryazev), the 12-field Markovsky rotation was used, in which six fields were allocated to perennial grasses.

The multi-field grass system also has disadvantages. For example, in rotations there are no intensive row and industrial crops, the use of fertilizers and ameliorants is limited, which affects the relatively low output per unit area at high costs.

Large areas occupied by crops of self-seeding leguminous grasses (alfalfa and clover) make it possible to abandon the application of nitrogen fertilizers. However, the productivity of arable land does not change significantly because of this.

This system is still used in sparsely populated countries with large land resources, for example, in Australia, where the average population density is one person per 1 km².

In Russia, the multi-field grass farming system in its pure form did not become widespread, although some of its elements, for example, soil-protective multi-field grass fodder rotations in combination with rotations of other systems, are successfully used. For example, in some regions of the former USSR republics: the Baltic states, Western Ukraine, and Belarus.

Improved Grain System

The improvement of the grain-fallow farming system occurred thanks to the introduction of one or two fields of perennial grasses into the rotation. Examples include:

• the four-field rotation of I. I. Samarin, which arose in Yaroslavl Governorate at the beginning of the 19th century: 1 — fallow, 2 — winter crops with undersowing of clover, 3 — clover, 4 — spring cereals;
• the Volokolamsk eight-field rotation in Moscow Governorate: 1 — fallow, 2 — winter crops with undersowing of clover with timothy, 3–4 — clover with timothy, 5 — spring cereals, 6 — fallow, 7 — winter crops, 8 — spring cereals.

Later, occupied fallows began to appear in rotations of the Non-Chernozem region, partially reducing the areas of clean fallow, grain legumes, and row crops.

In the chernozem regions, row-crop fields occupied by sugar beet, maize, or sunflower were introduced into grain (fallow) rotations: 1 — fallow, 2 — winter wheat, 3 — sugar beet or maize, 4 — spring wheat or barley.

The multi-field grass farming system also gradually improved to the improved grain one by reducing the area under perennial grasses and increasing the share of cereal crops.

The improved grain system became widespread in the Non-Chernozem zone. In grain-grass rotations, cereals accounted for half to 2/3 of the arable land, 15–25% under clean fallow, and 20–30% under perennial grasses. Row crops and grain legumes, as a rule, were not grown. Soil fertility was maintained through perennial grasses, fallow cultivation, fertilizers, primarily manure.

The introduction of perennial grasses and row crops into rotations significantly improved the fodder base of animal husbandry. The inclusion of row crops made it possible to improve soil cultivation techniques and fertilizer application and increased the general culture of farming.

In Western Europe, the improved grain system was widespread in Germany, Austria, and some regions of France.

The improved grain system was improved: areas of clean fallow were reduced, replacing them with occupied fallow, row crops were introduced into rotations, and a gradual transition to the convertible system took place. A. S. Ermolov called such transitional forms the improved grain system with a more or less developed convertible element.

At present, this farming system is used in the grain regions of the south and southeast of the European part, and less in Siberia. Under these conditions it has shown good effectiveness and has come to be called the fallow-row-crop system. In fallow-row-crop rotations, cereal crops account for 50 to 70% of arable land, row crops, grain legumes, and groat crops — 15–20%, and clean fallow — 15–20%. Reproduction of soil fertility is carried out with the help of intensive cultivation of fallow and row-crop fields, which are also a means of weed control, application of fertilizers, and measures for moisture accumulation. An example of a fallow-row-crop rotation can be the four-field rotation recommended by I. A. Stebut for farms with a potato specialization: 1 — fallow, 2 — oats, 3 — potato, 4 — spring crops. In beet-growing regions, a similar four-field rotation was used with sowing sugar beet after winter cereals.

At the beginning of the 20th century, the fallow-row-crop five-field rotation became widespread, in which two cereal crops were sown after fallow: in Siberia — two spring crops, in the southeast — winter and spring crops, followed by row crops and spring cereals.

In the modern version of the improved grain system — the grain-row-crop system — improvement of the structure of sown areas, introduction of rational rotations adapted to natural conditions, and the use of more advanced soil cultivation systems in combination with a scientifically substantiated fertilizer system and sowing of varieties of cereal and row crops have made it possible to use it quite successfully. In the grain-fallow-row-crop farming system, most of the arable land is occupied by cereals and row crops in combination with clean fallow. Soil fertility is reproduced by cultivation and the application of fertilizers.

The grain-fallow-row-crop farming system is more advanced; the output per unit area is significantly higher compared with the improved grain system. It is widespread in the steppe regions of the Volga region, Ukraine, the North Caucasus, the Central Chernozem zone, and in recent years in the steppe regions of Siberia, the Trans-Urals, and Kazakhstan.

The green-manure system can also be assigned to the improved grain system, in which the entire green mass grown on a fallow field is plowed in as green manure. The origin of this system dates back to ancient times: it was known in Ancient Greece, the Roman Empire, and the countries of the East. However, only at the end of the 19th century did Schultz-Lupitz in Germany formulate the foundations of a farming system using green and mineral fertilizers. It became widespread in regions with a sufficiently humid climate and poor sandy and sandy loam soils. Most often, bitter annual lupine was used as a green-manure plant, less often perennial lupine. After the development of non-alkaloid fodder lupine, it became most widespread. Later, plants for green manure began to be sown after harvest, after harvesting the main crop, and the green-manure system lost its independence, since stubble crops can be cultivated under any farming system.

In modern conditions, the green-manure system has been preserved in some regions of the Non-Chernozem zone, where perennial lupine is used, but green manure is not the only way to maintain fertility under these conditions.

Grass-Field System

The development of field grass sowing and the emergence of a number of farming systems with the sowing of perennial grasses led to the decision to unite these systems into grass-field husbandry. V. G. Bazhaev (1900) considered that the term “grass-field husbandry” was close to the German one, by which in Germany was meant a system of field cultivation in which a field is used for several years for annual crops, and then for several more years for growing grasses. As V. G. Bazhaev noted, these systems unite the shifting-fallow and pasture systems. Over time, grass-field husbandry expanded, including other systems with the cultivation of fodder grasses, including the improved grain system with grass sowing.

A. N. Shishkin (1894) also assigned grass-field husbandry to a system of field cultivation.

Only with the establishment of grass sowing in the fields do simple grain systems pass into grass-field systems — improved grain, pasture, and convertible.

A. N. Shishkin

L. I. Skvortsov (1890) subdivided the grain system of husbandry into: fallow-grain, grass-field, and convertible farming systems. By grass-field he meant the multi-field grass and steppe shifting-fallow systems. Thus, at the end of the 19th century, by grass-field husbandry, or system, several systems were understood, differing in intensity and basic features.

V. R. Williams developed the grass-field farming system, uniting the improved grain and multi-field grass rotations into one system with two rotations: field and meadow, which was effective under the conditions of organizing large collective and state farms with significant areas of agricultural land. The organization of a rotation with the sowing of perennial grasses and annual plants on meadows contributed to increasing the productivity of natural fodder lands several times, and the development of animal husbandry on this basis led to an increase in the amount of manure and an increase in the yield of grain rotations.

According to V. R. Williams, the grass-field system includes the following links:

• system of field and fodder rotations;
• system of main and pre-sowing soil cultivation;
• fertilizer system in the rotation;
• system of field-protective forest plantings;
• construction of ponds and reservoirs in steppe and forest-steppe regions;
• sowing with high-yielding varietal seeds.

The theoretical basis of the grass-field farming system was provided by ideas about the natural process of soil formation under the cover of vegetation. P. A. Kostychev and V. V. Dokuchaev in the 1880s, observing the results of plowing steppe chernozems after leaving a plot as fallow, came to the conclusion that soil fertility is restored under the action of natural, successively changing herbaceous vegetation. Steppe vegetation allowed the soil to accumulate humus and form a strong granular structure. According to P. A. Kostychev, structural soil can be formed only on virgin land and fallow. Improvement of structure was supposed to contribute to optimizing the water regime of the soil.

Recognizing the disadvantage of the shifting-fallow system in the long duration of restoration of fertility and soil structure, P. A. Kostychev and V. R. Williams established that the first phase of the sod process of soil formation — the phase of weedy fallow, in which a coarse structure is created — can be accelerated by soil cultivation. The second main phase — the formation of a finely cloddy structure under the influence of the root systems of loose-bush cereals — can be shortened by sowing these cereals in the fields. V. R. Williams wrote about the third phase:

The significance of the third phase reduces to imparting strength to the structural elements and to enriching the soil of the fallow with elements of the ash food of plants and nitrogen by deeply rooted legumes. The same effect and to the same degree can be achieved in cultivation by the simultaneous and joint sowing of loose-bush cereals and perennial legumes. Such are the three main propositions on which the grass-field farming system is based.

V. R. Williams

In field grass-field rotations, two fields were allocated to crops of a mixture of perennial legumes and cereals, and in fodder rotations, most of the arable land was allocated to perennial grasses with a long period of use. Spring crops were placed after the sod of perennial grasses. It was not allowed to sow winter and row crops after the sod, since it was assumed that the soil structure would then be destroyed more quickly.

The organization of the territory provided for the placement of forest massifs on watersheds, field rotations on slopes and plateaus, and fodder and vegetable rotations in valleys.

The grass-field farming system began to replace the fallow farming system on collective and state farms. The positive properties of the grass-field farming system include:

• cultural soil cultivation with the help of plows with skimmers;
• introduction of multi-field field and fodder rotations;
• organization of the territory;
• creation of field-protective forest plantings and reservoirs in arid regions.

In a number of cases, the introduction of the grass-field system contributed to increased productivity and the development of animal husbandry.

V. R. Williams contrasted perennial grasses with annual crops in their effect on soil fertility. He assigned to crops that accumulate organic matter and improve soil structure perennial grasses consisting of legumes and cereals. Despite the fact that his predecessors P. A. Kostychev and A. A. Izmailsky proved the ability of annual crops to improve soil structure, he held the opinion that these crops worsen soil structure. V. R. Williams proposed using only grass-field rotations in all regions of the country, regardless of the yield of perennial grasses for hay. In his theory it was asserted that manure cannot serve as a means of improving soil structure; because of fears of destroying the structure, the use of harrows and rollers in the cultivation system was excluded.

V. R. Williams overestimated the role of a strong structure and the importance of perennial grasses in recreating it. He considered the sowing of a mixture of perennial cereal and leguminous grasses obligatory, since, in his opinion, legumes alone could not solve this task. D. N. Pryanishnikov, N. M. Tulaykov, A. G. Doyarenko, S. P. Kulzhinsky, and N. S. Sokolov criticized the erroneous positions of V. R. Williams. Through long-term experiments, D. N. Pryanishnikov proved that a good soil structure is recreated not only under grass mixtures but also under pure crops of alfalfa or clover. D. N. Pryanishnikov determined the conditions for using grass-field rotations and gave rotations without perennial grasses.

Subsequent experiments also did not confirm the conclusions about a strongly cloddy structure as the main condition of fertility, or about a mixture of loose-bush cereals and legumes as the only means of improving soil structure. Research and farming practice also did not confirm the assertion about the inadmissibility of sowing winter and row crops after the sod of perennial grasses. Thus, in the North Caucasus, the Non-Chernozem and Central Chernozem zones, and some other regions, winter wheat and rye give much higher yields after the sod of perennial grasses than spring wheat.

Along with rotations, in the grass-field system great importance is assigned to soil cultivation. The system of autumn cultivation, including stubble peeling and plowing, became widespread. The quality of cultivation improved thanks to the use of a plow with a skimmer and deepening of the arable layer, especially of sod-podzolic soils. Fears about the destruction of soil structure under the action of disk implements, harrows, and rollers, which were recommended to be used only in crop care, were also unfounded.

The fertilizer system received some development, providing for a combination of organic and mineral fertilizers. However, V. R. Williams’s opinion about the uselessness of applying mineral fertilizers on structureless soils and applying manure in the form of raw humus was erroneous. Despite criticism of the grass-field system, some scientists promoted it in the 1930s–1940s and everywhere recommended it as the only correct and progressive one. However, later it was abandoned everywhere.

At present, the grass-field farming system is understood as a system in which more than half of the arable area is occupied by perennial grasses, and soil fertility is reproduced by growing perennial grasses and applying fertilizers. The grass-field farming system, with a justified combination of individual links, can be used taking into account local conditions in the zone of sufficient moisture, in particular, in some regions of the Non-Chernozem and forest-steppe zones, where high yields of perennial grasses are obtained.

Field grass sowing should not be identified with the grass-field farming system. It is a component of different systems, for example, multi-field grass, convertible, improved grain, which differ sharply in intensity.

Convertible System

Convertible farming system — a system in which the key importance is the alternation in crop rotation of soil-depleting crops, for example, cereals, with soil-enriching ones, for example, grain legumes or perennial grasses.

The distinctive features of the convertible system are:

• plowing of natural fodder lands and turning them into arable land, with the exception of part of highly productive meadows;
• cultivation of fodder, most productive crops;
• abandonment of clean fallow and its replacement with leguminous grasses;
• alternation of crops that deplete and enrich the soil — convertible alternation.

In Western European countries, the abandonment of the fallow and fallow-grain farming systems occurred more rapidly than in Russia. Therefore, the convertible system became more widespread in Europe and much earlier. The beginning of this system was laid in Flanders and Flandria — part of the lands of present-day Belgium and Holland — in the 16th–17th centuries. It quickly occupied a dominant position in England, then in France (18th century), and Germany (19th century).

Plants according to their need for nutrients can be divided into three groups:

• crops that deplete the soil, primarily cereals, consuming a significant amount of nitrogen and phosphorus;
• crops possessing the property of assimilating nitrogen from the air and enriching the soil with it; these include legumes and grain legumes;
• root crops and tuber crops, consuming much potassium, and less phosphorus and nitrogen.

In the convertible system, winter crops were placed after legumes and grain legumes, and row crops after winter crops. Row crops were followed by spring cereal crops. Repeated sowings of cereals were not allowed. Alternation in the rotation provided for an annual change in the fields. To maintain and increase fertility in the structure of sown areas, half of the arable land was allocated to cereals, and the second half to legumes and row crops. Clean fallow was replaced by occupied clover fallow. The transition to the convertible system meant that purely grain farming gave way to farming with developed animal husbandry and the cultivation of industrial and row crops. The development of animal husbandry led to an expansion of crops of leguminous grasses and fodder root crops.

In England, the Norfolk rotation, typical for many of its regions, developed, being a classic example of convertible alternation: 1 — winter wheat, 2 — fodder root crops, 3 — barley with undersowing of clover, 4 — clover. In this rotation, the ratio of crops typical for this system is expressed: cereals — 50%, row crops — 25%, and legumes — 25%.

The climatic conditions of Western Europe contributed to the abandonment of clean fallow: a sufficient amount of atmospheric precipitation and a long growing season, allowing the soil to be well prepared for sowing winter crops after harvesting clover, which replaced the fallow field. Failures sometimes also contributed to the introduction of convertible rotations. Thus, in France, on permanent plots of sugar beet, the infestation of roots by nematodes constantly increased; for this reason, beet began to be introduced into rotation as a row crop.

A. V. Sovetov, trying to optimize convertible alternation to the conditions of Russia, noted that the convertible system possesses great flexibility. Most often, one field of a convertible rotation is occupied by clover or other leguminous grasses; however, there are rotations in which, instead of perennial grasses, annual legumes are used for green fodder, hay, or grain.

The inclusion of row crops in the rotation required deep soil cultivation, in particular, deep plowing and plowing with subsoilers, as well as the application of organic fertilizers, primarily manure, whose effect extends to subsequent crops.

The transition from fallow-grain three-field rotation to the convertible system, including intensive application of fertilizers and deep soil cultivation, contributed to an increase in the average wheat yield in Western Europe from 0.7–0.8 t/ha (18th century) to 1.6–1.7 t/ha (1840–1880), and against the background of mineral fertilizer application — to 2.5–3.0 t/ha (1900–1930). In recent decades, the modern convertible farming system makes it possible to obtain more than 4.0 t/ha.

Supporters of the convertible system as early as the 18th–19th centuries among Russian scientists were A. T. Bolotov, I. M. Komov, M. G. Pavlov, P. A. Kostychev, I. A. Stebut, A. N. Engelhardt, and others, who made many proposals for improving this system and adapting it to the conditions of Russia.

Before the Revolution, the convertible farming system was successfully used only on individual landlord farms, mainly in beet-growing ones. For the conditions of one-sided grain or grain-livestock farming, it was inconvenient. Peasant farms were economically unprepared for the transition to the convertible system. The communal method of land use also hindered this. At the beginning of the 20th century, supporters of the convertible system were D. N. Pryanishnikov and S. P. Kulzhinsky, who attached especially important significance to correct alternation and the introduction of leguminous crops into rotation.

The transition from the grain-fallow system to the convertible one was a progressive step in the development of agriculture. According to modern ideas, convertible rotation successfully solves the issues of increasing soil fertility through the application of fertilizers, sowing leguminous crops, deep soil cultivation, and weed control.

In modern domestic farming, the convertible system, along with other intensive farming systems, is widespread in the Central Chernozem zone and the North Caucasus. However, the requirements imposed on agriculture at present do not allow it to be called optimal.

Industrial-Factory (Row-Crop) System

The development of commercial farming in Russia in the middle of the 19th century led to the appearance of the row-crop, industrial-factory, or market-garden farming system, primarily in regions specializing in the production of sugar beet, sunflower, potato, and vegetables. The cultivation of these crops determined the connection of agriculture with the processing industry. For this reason, A. V. Sovetov, A. S. Ermolov, and other scientists called this system industrial.

The industrial-factory system is based on the intensification of labor, sufficient application of fertilizers, and depends almost not at all on soil and climatic conditions. A. V. Sovetov noted that in Russia in the second half of the 19th century, in some places the fallow system had long been forgotten and replaced by new ones. For example, he assigned Yaroslavl Governorate to such regions, where in Rostov market gardening, potato was cultivated for the starch and distilling industry, and sunflower and sugar beet were grown. In 1890, A. I. Skvortsov noted that on farms the technical convertible system has a pronounced character:

… here they not only do not allow the successive cultivation of two cereals, but more often, on the contrary, allow the cultivation of two root crops, even of the same species.

A. I. Skvortsov

However, in pre-revolutionary Russia this system was even less widespread than the convertible one.

In the industrial-factory system, arable-suitable lands are used mainly for crops of valuable cereals, grain legumes, industrial, and highly productive fodder crops. The remaining part of the meadows is converted into highly productive hayfields and pastures. The structure of sown areas is determined proceeding from the specialization of the farm and natural-economic conditions.

Clean fallow is introduced periodically; perennial, primarily leguminous, grasses in the main rotations occupy a small share of arable land or are entirely absent. On soils subject to erosion, the share of grasses increases.

Zonal Farming Systems

The large number of zones in Russia with different soil-climatic and economic conditions causes a diversity of applied forms of farming systems taking into account the achievements of agronomic science.

Zonal farming systems must:

• be soil-protective;
• be based on scientific achievements, technology, and best practice;
• be based on intensive technologies;
• represent an agricultural complex;
• ensure sustainable farming;
• create the maximum amount of high-quality crop production with minimal expenditures of labor and means.

Reproduction of fertility is the most important indicator of zonal farming systems, based on a normative-technological basis using calculation-balance methods of programming fertility and yields. High and stable yields of cereals up to 4–5 t/ha, silage crops up to 40–60 t/ha, and other crops are obtained by enterprises with the most fully mastered farming system. Farming cannot be developed according to some one universal scheme. At each enterprise, the farming system must be improved annually taking into account new tasks and opportunities in the directions of increasing intensification, ecological, economic, soil-protective, and social efficiency.

The effectiveness of a farming system is assessed by individual agrotechnical, reclamation, organizational, and other measures included in its composition, from which the effectiveness of the system as a whole is determined. The main indicators of the economic effectiveness of a farming system are:

• level of productivity (amount of production in conventional units per 1 ha of arable land);
• level of costs;
• profitability of production;
• labor productivity.

Alternative Farming Systems

Modern intensive farming systems, providing for the active use of chemicalization and mechanization means in the cultivation of agricultural crops, have received the name traditional. In the middle of the 20th century, a new period began in the development of intensive systems, characterized by a complete or partial abandonment of the use of mineral fertilizers and chemical plant protection agents and an increase in the importance of biological sources of plant nutrition and biological and mechanical methods of protection. These systems came to be called alternative.

The main reason for the development of this direction is connected with the sharply negative impact of intensive farming systems on soil, the environment, and product quality due to the widespread use of mineral fertilizers and chemical plant protection agents. In addition, the emergence of this direction was facilitated by the limited nature of non-renewable resources consumed in farming in increasing quantities, the instability of product markets, and rising prices for machinery, fertilizers, pesticides, and fuel.

Alternative farming systems are called differently in different countries, but have insignificant differences. In the USA and Canada, for example, an organic farming system is used, in which the production, processing, and storage of crop production occur without the use of synthetic fertilizers, pesticides, and growth regulators. Only materials consisting of substances of animal, plant, and mineral origin are permitted. Great importance is assigned to crop rotation, green-manure crops, primarily legumes, the use of plant residues and organic wastes of non-agricultural origin. Soil cultivation, depending on conditions, is reduced to a minimum and focuses attention on protecting the soil from erosion; non-moldboard chisel and disk implements predominate.

In France, a biological farming system is used, in which the use of chemical fertilizers, and primarily easily soluble ones, is not permitted. It is based on: the application of organic fertilizers, which are often pre-composted; practices that increase the biological activity of the soil and neutralize excessive acidity. Great attention is paid to a justified crop rotation with gentle saturation with individual crops and to the use of green-manure crops. To control pests, pathogens, and weeds, preventive measures, mechanical, biological, and fire methods are used.

In Sweden, Switzerland, and some other countries, an organic-biological farming system is used, based on creating a “living and healthy soil” by maintaining and activating the activity of soil microflora. Fields are occupied by vegetation as long as possible, crop residues are incorporated into the topsoil, the rotation is saturated with leguminous and leguminous-cereal crops, and only organic and some slowly soluble mineral fertilizers are applied. Plant protection is similar to the biological farming system.

In Germany, Sweden, and Denmark, the biodynamic system is widespread. In the basis of this system, along with the principles common to all alternative systems, there are some differences: farming is conducted taking into account not only earthly (natural) but also cosmic rhythms; the influence of cosmic forces on agricultural production is used; special biodynamic preparations are applied, for example, “humus,” “silica,” “compost,” extracts, decoctions, and fermentation products from plants. All agrotechnical practices are recommended to be carried out during favorable periods consistent with the phases of the Moon and the zodiacal cycle.

In a number of countries, an ecological system is used. It is based on limiting the use of pesticides and flexible use of mineral fertilizers. The use of water-soluble forms is permitted taking into account the mechanical soil texture.

All alternative farming systems are characterized by a common principle — reduction or complete abandonment of the use of mineral fertilizers and pesticides, transition to nutrients of plant origin, and obtaining ecologically safe crop production.

The first studies of alternative farming systems in the world revealed their advantages and disadvantages. The advantages of these systems include high ecological friendliness, reduced energy consumption and consumption of exhaustible resources, and improved product quality. The main disadvantage is a decrease in crop yields. The use of alternative systems does not imply a return to low-productivity farming systems, but a search for and improvement of technologies on the basis of scientific knowledge, laws of nature, and their optimal use.

Biologicalization, that is, the intensification of biological factors to reduce the negative impact of the anthropogenic factor of farming and, while increasing its effectiveness, for the maximum realization of the potential productivity of crops and reproduction of soil fertility in accordance with the ecological principles of nature management, is the most important task of developing alternative farming systems.

The main factors of biologicalization of farming:

• knowledge and rational use of the laws of nature;
• reproduction of soil fertility, improvement of agronomic and biological properties, mainly through crop rotation;
• use of high-yielding varieties and hybrids adapted to specific soil-climatic conditions;
• development of scientifically substantiated crop rotations;
• maximum effective use of biological nitrogen in agrocenoses;
• application of all types of organic fertilizers, expansion of the share of green manuring, limited use of mineral fertilizers taking into account optimization of plant nutrition;
• ecological plant protection system, use of biological practices and means;
• differentiated soil tillage system taking into account the requirements of crops and soil-climatic conditions.

Alternative farming systems are built by solving a complex task from the imposed ecological and economic conditions.