Crop Rotation System

Preparation for Design

For developing the on-farm land management project, the design organization is provided with the following information:

• basis for design;
• long-term specialization indicators;
• inter-farm relations;
• organizational and management structure of production;
• list of settlements;
• location of livestock facilities;
• areas of agricultural land, distinguishing arable land and perennial plantings;
• areas being converted to arable land and other types of agricultural land;
• areas intended for irrigation and drainage, as well as for radical improvement;
• structure of sown areas by crop;
• average yields of crops and natural forage lands over several years;
• livestock numbers for each animal species and average productivity;
• volume of gross livestock and crop production, including marketable and for on-farm use;
• measures for soil erosion protection and control of pollution of water bodies and air.

To prepare the project, preparatory work is carried out:

• planning-cartographic, land-accounting, survey, land-evaluation and design materials, information on the current state and long-term development plans of the enterprise are studied and systematized;
• the lands of the agricultural enterprise are surveyed, and proposals for their further use are collected and developed, for example, lands subject to reclamation, radical or surface improvement and suitable for conversion to arable and other lands are identified; plots suitable for establishing orchards, vineyards and berry fields are identified; plots of soils at risk of erosion are determined;
• the dynamics of erosion processes and the degree of soil erosion are determined;
• hydraulic soil-protection structures and protective forest plantings, if present, are surveyed;
• the on-farm road network, production points of the farm, field camps, summer livestock camps are surveyed, and the feasibility of their functioning is determined;
• water supply sources for irrigation and on-farm needs and their condition are identified;
• crop placement schemes for the last two years are compiled.

Based on the survey results, the land inventory is refined. Survey data are entered in field books, reports and drawings.

When developing a crop rotation system, special attention is paid to a detailed study of arable lands. For these purposes, soil maps, agrochemical and erosion cartograms, information on the history of land plots, their location, relief and distance from production facilities, roads, and crop yields over the last 3–5 years are used.

Drafting the Project

The crop rotation system project consists of graphic and textual parts.

Graphic part of the project — the land use map of the enterprise, including soil, agrochemical, erosion maps and other graphic materials.

Textual part of the project — an explanatory note with a current analysis of the state of production and lands, justification of the project, including agro-economic and other calculations.

Crop rotations are placed on the main land masses — arable land, which is the most valuable and productive part of the agricultural enterprise’s land use and is closely connected with other elements of the agrolandscape.

The project includes measures to improve land use and a production development plan, for example, construction or location of production facilities, roads, organization of crop rotations and forage lands, measures to protect water bodies, land and air from pollution, and a project implementation plan. The project determines annual work volumes, needs for seed material, fertilizers and agrochemicals, and needs for agro-reclamation works and machinery.

The structure of sown areas is determined on the basis of the tasks of the long-term production development plan or business plan and the satisfaction of on-farm needs for feed, seed material, etc. Designing the structure of sown areas is based on comparing quantitative indicators expressed in monetary terms, feed or protein units, etc., produced per 1 ha of arable land. Labor and monetary costs of production should be minimized.

In accordance with the principle of adaptability in constructing crop rotations, all crops included in the structure of sown areas must be zoned according to local soil-climatic conditions and accepted agricultural practices. On the basis of the developed structure of sown areas, the number of crop rotations, their area, composition, ratio and schemes of crop alternation are determined, taking into account the results of studying the soils of arable lands.

To determine the optimal number, type and kind of crop rotations, different variants of systems are compared, assessing them by:

• volume of crop production per 1 ha of arable land;
• volume of feed production as a whole and separately by type;
• productivity of agricultural machinery;
• volume of on-farm transport;
• availability of labor resources and degree of mechanization of production;
• distance from settlements and production facilities.

When designing crop rotations, their efficiency is assessed first at the level of individual crops, and then at the level of various variants of the sown area structure in order to determine the most economically and agronomically optimal combination of cultivated crops.

Economically, it is more expedient to place crops in large blocks, which allow more efficient use of agricultural machinery, and to narrow production specialization. Fields of crop rotations should be a single homogeneous mass with a regular configuration, preferably rectangular.

Agroforestry reclamation measures are planned taking into account the existing system of protective forest plantations; for this purpose, the creation of new or reconstruction of existing plantations for various purposes is provided — field-protective, water-regulating, windbreak forest belts around production facilities, field camps or water sources. If necessary, afforestation of ravines, steep eroded slopes, and sand fixation are planned. The project provides agro-reclamation measures for runoff regulation and stabilization of growing ravines with hydraulic structures.

At the design stage, lands subject to protection are identified, with measures to prevent pollution. In large livestock complexes, treatment facilities and irrigation fields are provided.

The final stage of designing a crop rotation system is the development of a project implementation plan, which determines the deadlines and sequence of measures, volumes and cost of work, criteria for assessing quality of execution, and the degree of participation of contractor organizations and the enterprise itself.

Plan for Transition to Crop Rotation

In the case of a transition within development to a new crop rotation, a plan is drawn up in the form of a transition table, which includes the crop alternation scheme by development years, while preserving the structure of sown areas. During the transition period, the planned yield level of crops and the gross harvest provided by the structure of sown areas must be maintained.

To prepare the transition plan, a predecessor map is used, which indicates the placement of crops by fields over the previous two years. The condition of each field, the degree of its weed infestation, fertilizers applied, methods of tillage and other agricultural practices are also determined.

The transition plan to crop rotation establishes the order of crop alternation in each field until the end of the crop rotation development period; for each crop, a system of agronomic measures is developed that takes into account preceding crops, weed infestation of fields, the need for reclamation works, etc.

If in the transition year a new crop must be placed after a poor predecessor, organic and mineral fertilizers are additionally applied under it. In the first years of crop rotation development, one should strive for one field to have one crop or several crops similar in cultivation practices.

When planning the development of a new crop rotation, one strives to complete the transition as quickly as possible.

For developing transition tables, the following order is followed:

1. The plan and sequence of development of new land areas included in the crop rotation are determined; for plowing up, lands of lower economic value are chosen first.

2. Crops sown last year are specified, that is, winter crops and perennial grasses.

3. The most valuable introduced crops are placed after the best predecessors.

4. Less demanding crops, taking into account their market value, are placed after the remaining predecessors. Spring crops are placed in descending order of their value.

5. Clean and occupied fallows are assigned to the most weed-infested fields with the worst predecessors.

6. Fields divided by several predecessors should preferably be combined.

7. In crop rotations with perennial grasses, a place for their undersowing is determined. In the southern regions of the country, perennial grasses are undersown under spring cereals; in the Non-Chernozem zone on lighter soils — more often under winter crops, on heavier soils — under barley, oats, spring wheat and annual grasses.

8. If there are combined fields, crops most similar in biology and cultivation technology are placed in them, for example, early spring crops with early spring crops, winter cereals with winter crops, row crops with row crops, etc.

9. The transition plan to the new crop rotation is drawn up so that each crop in the first transition year is placed after good predecessors.

Deviations in the transition plan are permissible if they do not lead to a significant change in the structure of sown areas. For example, in arid regions after non-fallow predecessors under conditions of a dry autumn, winter crops will not produce normal seedlings, so the field can be left for sowing spring wheat, barley and, conversely, in favorable years winter crops can be expanded at the expense of spring crops. As a result, grain yield from the crop rotation area will be higher, and objective changes in the crop rotation cannot be attributed to a violation.

Transition plans are drawn up for each introduced crop rotation, accompanied by explanations of those deviations from the main alternation scheme that may occur in the transition period. Twice a year — in spring after sowing spring crops and in autumn before sowing winter crops — the correctness of crop placement is verified on the basis of the established plan and transition table.

Example. A 3-year plan for developing a crop rotation with the scheme: 1 — clover fallow, 2 — winter cereals, 3 — spring wheat, 4 — annual grasses (vetch + oats), 5 — winter crops, 6 — barley with clover undersowing.

To confirm the correctness of the transition plan, a table of sown areas under crops by years is drawn up.

Transition plans to near-farm crop rotations are similar to plans for field crop rotations. Plans for transition to hay-pasture and soil-protective crop rotations require a longer period.

Assessment of Efficiency of Individual Crops

To assess individual crops of a crop rotation, the following indicators are used:

• yield of main and by-products (t/ha);
• product quality, its food, feed or technical value;
• amount of plant residues (t/ha) and content of nutrients in them (kg/ha);
• economic and energy output per hectare in rubles and energy units;
• labor costs per hectare and unit of production in person-hours, material and monetary costs in rubles and energy in Joules per 1 hectare and 100 kg of production;
• net income per hectare and per ruble of costs in rubles;
• profitability, %.

The basic indicator for assessing agricultural crops and crop rotations is yield. For correct comparison, it is advisable to determine net yield, that is, barn yield minus the seeding rate.

To assess the economic efficiency of fallow fields, costs and output of main and by-products in different links of crop rotations are compared.

The efficiency of feed production is determined by the output of feed units, protein and feed-protein units per 1 ha. The assessment is made both for groups of forage crops — grain forage, silage, succulent, rough — and for species of forage plants within a group, choosing the most profitable. Preference is given to crops that most favorably combine feed qualities and cost. Some crops, for example, fiber flax, tobacco, sunflower, cannot be assessed in feed units, so they are assessed by the market value of production per unit area of arable land.

When assessing individual crops, their effect on the physical properties of soil is taken into account, primarily structure and water regime, soil-protective and phytosanitary capacity. The amount of plant residues left is determined by the output of main products using coefficients and nutrient content according to reference data.

Assessment of Crop Rotation Efficiency

The indicator for assessing the efficiency of crop rotations is output per 1 ha of arable land, expressed in comparable values, for example, in grain, feed and feed-protein, energy units or rubles, taking into account quality indicators.

For a comprehensive assessment of crop rotation efficiency, the following indicators are used:

• output of main products per 1 ha in feed, feed-protein or grain units;
• average cost of gross output in rubles, labor costs in person-hours and means per unit of main product and per unit of sown area, net income in rubles per 1 ha, profitability (%);
• stability of main product production by the coefficient of variation;
• soil-improving role of the crop rotation, which is assessed by the dynamics of changes in the balance of organic matter, physical and chemical properties of soil, by the amount of plant residues and the content of nutrients in them;
• soil-protective efficiency of the crop rotation, assessed by an increase in erosion resistance and a decrease in the intensity of erosion processes;
• phytosanitary efficiency, which is assessed by changes in the degree of weed infestation of crops, disease incidence and pest damage.

To determine the gross productivity of a crop rotation, the main and by-products of all crops, expressed in comparable values, are summed. The resulting sum is divided by the area of all fields of the crop rotation, and the output per 1 ha is determined.

Comparing crop rotations with different structures of sown areas, those that provide maximum productivity with minimum labor and monetary costs are chosen. At the same time, it can be considered that in a given crop rotation the soil-climatic resource and biological potential of crops, as well as material and labor resources, are used most fully and rationally.

The net income of a crop rotation per 1 ha and per 1 ruble of annual costs characterizes overall economic efficiency, and the ratio of net profit to costs characterizes the profitability of the crop rotation.

Assessment of Efficiency by Ecological, Energy and Soil-Protective Indicators

Under market economy conditions and changes in prices for materials and services, an objective integral assessment of a crop rotation can be its energy efficiency.

Energy efficiency of a crop rotation — total energy costs for growing all crops of the crop rotation and the total energy content of harvests in order to determine the degree of recovery of energy costs by the energy content of products. Net energy income is calculated as the difference between the energy content in harvests and the total energy costs for growing all crops.

Energy efficiency coefficient — the ratio of net income to energy costs.

Bioenergy coefficient (efficiency) — the ratio of energy obtained with harvests to energy costs.

Energy cost of production — calculated per unit of harvest or protein. The energy assessment of crop rotation efficiency can be converted into monetary units if the cost of one kilojoule is known and thus translated into an economic assessment of crop rotation efficiency.

The soil-protective assessment of crop rotation efficiency is determined taking into account the degree of development of erosion processes and the presence in the crop rotation of crops and agricultural practices that can stop these processes and protect the soil from destruction.

The ecological efficiency of a crop rotation is assessed by phytosanitary potential, which reflects a reduction or complete abandonment of chemical plant protection products. Depending on the degree of use of legumes, manure, straw for fertilizer, green manures, sowing of perennial grasses and catch crops, an ecologically effective structure of sown areas can be determined. These practices allow reducing the use of mineral fertilizers and pesticides, protecting the environment and agricultural products from pollution.