The shift from crop rotation to monoculture is one of the main causes of soil erosion. A corn-wheat-grass rotation has an erosion rate of 6.7 Tn/ha/year compared to 50 Tn/ha/year for a continuous corn crop. Because of these erosion rates, the loss of soil fertility is evident, increasing the dependence on inputs to cover this decline in fertility. Normally, these inputs are not composted organic matter but chemical fertilizers that can also destructure the soil, in addition to other collateral effects.
Crop rotation is the repeated establishment of an orderly succession of crop species on the same plot. It is the opposite of monoculture, or growing the same crop on the same plot over time.
If rotation is the orderly succession of crops that are repeated over a number of years, the alternative is the simultaneous cultivation of the species involved in the rotation. In this case, the farm is divided into different plots, each of which is devoted to a different crop each year, until the rotation is complete. These plots are called “alternative leaves” or “amelgas”.
The polyculture allows to fight against pests and diseases, let’s see how and which associations to favor.
Defense mechanisms of polycultures against pests
Lower pest damage in polycultures may be due to the fact that they are less attractive to pests :
The pest does not find the crop it usually feeds on
Organic agriculture uses a set of techniques to achieve its goals of producing high quality food, free of contaminants, while preserving the natural environment. These techniques are aimed at controlling the factors on which crop growth and agricultural productivity depend, such as: water harvesting and conservation, plant nutrition, pest and disease control, and the management of weeds that may at times limit crop growth. Another important factor is the use of crop varieties adapted to local conditions.
Spatial and temporal diversification, as well as soil protection and the addition of organic matter, are the basic strategies of ecological techniques.
In nature, there is a set of processes that allow natural ecosystems such as forests, estuaries and others to function with great efficiency. In many agricultural systems, these functions have been removed or severely diminished by management, so that constant intervention is necessary to repair the broken balances. Unfortunately, we do this with substances and methods that often affect the development of many organisms, deteriorate the productive base (the soil), the environment in general and can even affect humans, including the toxic substances we apply to kill insects, bacteria, fungi and plants.
This is why it is essential to know which functions of nature can be used in the development of organic agriculture in order to engage in organic farming.
The main functions present in natural systems that need to be enhanced in organic production systems are:
▪ Efficient use of resources.
▪ Biotic regulation and stability.
▪ Soil protection.
▪ Nutrient recycling.
▪ The water cycle.
▪ Environmental stability.
Efficient use of resources
Organic agriculture is defined as a set of production systems committed to producing food free of synthetic chemical pollutants, with high nutritional and organoleptic value, contributing to the protection of the environment, reducing production costs and allowing farmers to obtain a decent income.
For this reason, organic production systems do not use pesticides to control pests, diseases and weeds, and do not use methods that lead to deterioration of the soil and the environment in general. In animal husbandry, no antibiotics, hormones or other drugs are used in feed or preventive treatments, and husbandry is based on systems that allow for maximum animal welfare.
Organic farming is emerging
Organic agriculture is governed by a set of basic principles that can be described as follows:
The soil is a living and dynamic environment
It is not only our genes that influence our health, but also the food we eat on a daily basis. That’s why the way food is produced is important to us, not only for our health, but also to preserve the environment. In this article we explain what organic food is, what characterizes it, how it is produced and why it is better than conventional food.
What is organic food?