The primary goal of agriculture is to get good yields, the more the better. Farmers and agronomists utilize various methods to increase productivity, and crop rotation is one of the simplest yet effective ways.
So, the answer to the question “What is the purpose of crop rotation?” can be simply defined as ‘’to boost harvests”.
What Is Crop Rotation?
This concept means just what its name implies. The crop rotation definition can be put like changing different kinds of crops year by year in the same field. A cycle may include a different number of years, from 3 up to 7+ planting various crops in turns and/or leaving the land fallow to recover. In this case, areas may be either unused or used as green leys for livestock.
The last option is even better as it provides organic manure produced by cattle. Another system employs the changing species approach to make cover and green manure that not only gives food for livestock but protects lands from erosion and saturates soils with plant remnants.
Rotational cropping dates back to times immemorial. Benefits of crop rotation were noticed as early as in 6,000 BC by ancient Egyptians and were successfully used by the ancient Romans and Greeks as well. They noticed that planting crops in a certain sequence enhanced yields and improved soils, even though there were no chemical studies to explain this trick scientifically. One of the first evidence to teach how to implement the crop rotation system was the Bible. The Jews were instructed to leave their fields fallow every seventh year (the so-called Sabbath of the land).
The 3-cycle crop rotation was first introduced in Ancient Rome. The scheme could be represented by three key milestones: ‘food, feed, fallow’. ‘Food’ stood for cereals like wheat that was grown for human needs. ‘Feed’ implied forage for domestic poultry and cattle. ‘Fallow’ meant leaving the land uncultivated to give it ‘rest’. Besides, our ancestors understood that certain crops (like sunflower) heavily drain soils, so the fallow year was highly recommended.
This scheme has been successfully used till present days, even beyond any scientific knowledge.
Why Was Crop Rotation Beneficial To Farmers?
The development of botany and chemistry answered the question “Why is crop rotation important?”
The matter is that certain plants devastate the land of one type of nutrients while releasing the others. In their turn, the produced nutrients are required for the development of the other species.
There is no standard crop rotation chart though, even though certain regularities could be traced.
A common scheme entails planting root-leaf-legumes. What does crop rotation mean in this case?
Leaf plants release phosphoric acid required by root plants. Root plants produce potassium that is highly needed by legumes. Legumes release nitrogen that is crucial for plant growth.
The choice and sequence of rotated species depend on various factors:
- financial possibilities;
- available machinery;
- personal and trade needs;
- family farming traditions;
- peculiarities of agriculture in a certain region.
There is a system in South Africa that lasts 36 years. It entails growing woods and shrubs for 35 years and burning them after that to sow finger millet in the 36th year. Yet, the most frequent cycle consists of 3 years.
Various farmers found their ways to gather high harvests and share their experience. Examples of sequence may include:
- Corn-oats-alfalfa or clover-fallow or pasture
- Winter: wheat-wheat-rape-wheat-wheat-soya/sunflower for 2 years
- Summer: corn(maize)-soya-sunflower-cotton-corn-soya-wheat
7 Benefits You Can Enjoy Implementing The Crop Rotation Approach
- Saturation of nitrogen. It is the key chemical element required for healthy plant development. Nitrogen is used to create blocks of proteins and chlorophyll. Even though there is nitrogen in the air, it is not suitable for seedings. If soil lacks nitrogen it is provided by fertilizers.
- Optimization of expenses saving on chemicals. There is no need to buy nitrogen fertilizers (nitrates and nitrites) if this element is released by the previously planted crops (beans in particular).
- Nature protection. The chemical form of nitrogen pollutes soils and waters. Besides, plants absorb but a small part of nitrogen from fertilizers, the rest harms our ecology.
- Water retention. Alternative crops help keep water in deep soil layers. Plants will be able to use it in case of droughts.
- Reduced usage of pesticides. Certain species are attacked by certain pests, for example, potatoes are cut up by Colorado beetles. They are killed with target chemicals. When they are used for many years, excessive amounts pollute nature being harmful to all living beings.
However, if you plant, for example corn or wheat, they will leave the field, as they simply don’t eat that. At the same time, these insects are quite comfortable with tomatoes or aubergines – so this change won’t solve the problem.
- Protection from erosion. Different seedings have different root systems, either shallow or deep. They penetrate soils on alternative levels, thus improving soil porosity. Also, green leys cover lands and protect them from being exposed directly to winds and rains that destroy the land surface.Certain crops that grow underground (peanuts, potatoes, sugar beets) are known for low post-harvest residue unlike maize (corn) or sugarcane. The first group of plants needs frequent cultivation and thus causes much erosion while the other does not.
- Increased yields. Alternative release of needed nutrients boosts agricultural productivity.
What Is Monoculture Farming?
The meaning of monoculture farming can be defined as growing the same plant species in one area during several years in a row.
This approach can have certain advantages when there are different types of soils on the farm. This way, steep hills are covered with forage plants to reduce erosion while dry areas can be good for growing drought-resistant crops.
Besides, as certain species need a certain level of fertility, it is easier to optimize fields for the same crop.
This practice can be applied when the same land is used for forage cultures.
The disadvantage of a monoculture is the lack of nitrogen in soils if no legumes are seeded there. Another minus is the erosion issue because tilled (cultivated) crops are likely to cause it. In terms of diseases and pests, monoculture requires continuous usage of the same chemicals to tackle the issue.
Using The Satellite Monitoring For Crop Rotation Decisions
Since crops are location-based, GIS (Geographic Information System) introduces farm management software to help farmers make timely and well-informed decisions. Crop Monitoring, a digital agro-platform, in addition to a comprehensive assessment of the field, also provides farmers with weather forecasts, fertilizer maps, problematic areas analysis, among many other features, which significantly reduces costs.
How it works in Crop Monitoring
Each farm has its own main crops that it focuses on. The sustainability of the field for the specific crop cultivation or the decision to rotate crops is based on comprehensive monitoring and a full-fledged analysis of the history of vegetation state, as well as weather data.
“Crop Monitoring” is capable of implementing a full complex of monitoring tasks. It allows the user to track vegetation rate along with weather conditions such as daily precipitation, min/max air temperatures, and weather risks for the selected growing season. Moreover, vegetation can be tracked not only by the NDVI index but also by MSAVI, NDRE, NDMI, and ReCl, each of which is efficient at a certain stage of crop growth.
The user is able to add the crop growth data to the “Field history” tab.
For Ukraine, Romania, and Bulgaria there is a ready-made classification of crops and the system is able to display the crop rotation data, once you select the field.
Monoculture Farming vs Crop Rotation: How To Make The Right Decision?
Each method has its minuses and pluses. However, the first-hand practice provides evidence that the crop rotation system increases outputs and reduces inputs. Correspondingly, continuous mono farming brings poorer results year after year.
Monoculture farming repeatedly takes the same nutrients from soils thus draining them, pollutes nature with similar chemicals to battle pests, weeds and diseases, provokes erosion with similar root systems.
However, when a farmer sees that the same plant repeatedly brings profit on certain fields, then it does make sense to sow it year after year.
Each season is a challenge and involves a great degree of risk. Even with well-balanced and informed calculations, there are failures sometimes.
Experience shows though that rotative cropping is more productive than monocultural one.
A rotation plan developed by professionals addresses the main mono farming disadvantages: soil infertility, erosion, continuous invasion of pests.
Thus, farmers have greater chances to use their fields as efficiently as possible.