Microorganisms and their importance in the soil: The secret of a sustainable agriculture
When we think in agriculture, we often focus on the development of the plant, but we rarely consider the importance of proper management of the soil in which crops are grown. Soil is a vital resource that sustains our lives and provides the food that is indispensable for humanity, and its health is essential for sustainable agriculture and food security.
At first glance, soil may appear lifeless, but in reality, it is teeming with microscopic life. Healthy soils harbour a wide variety of microorganisms, including bacteria, fungi, protozoa, nematodes, etc. These organisms, which often go unnoticed, play an essential role in the functioning of terrestrial ecosystems.
Among the soil-dwelling microorganisms, many are beneficial to plant health soil quality in general. These microorganisms perform a number of vital functions:
1. Decomposition of organic matter: microorganisms break down organic matter in the soil, such as fallen leaves and plant debris. This action releases essential nutrients that can be absorbed by plants to support their growth.
2. Nitrogen fixation: nitrogen is one of the most important nutrients for plant growth. Some bacteria have the ability to fix atmospheric nitrogen in a form that plants can metabolise.
3. Protection against pests and diseases: some microorganisms act as biological control agents, helping to prevent plant diseases by competing with pathogens or producing antimicrobial compounds.
4. Improvement of soil structure: other microorganisms, such as bacteria or fungi, generate soil aggregates that improve soil structure, porosity and water holding capacity.
5. Nutrient cycling: they participate in the decomposition and release of essential nutrients, such as phosphorus, potassium and various micronutrients (zinc, iron, copper, calcium), which are essential for plant growth.
Unfortunately, modern agriculture has engaged in practices that often damage the diversity and population of beneficial microorganisms in the soil. Excessive use of chemical fertilisers and pesticides, intensive tillage and lack of crop rotation are practices that can damage or unbalance the microbial ecosystem present in the soil.
For example, chemical fertilisers may provide nutrients to plants, but they can also lead to soil acidifcation and negatively affect beneficial microorganisms. Similarly, pesticides intended to kill pests can negatively affect other microorganisms in the soil, which can trigger a cycle of dependence on agricultural chemicals.
Fortunately, there are agricultural practices that can promote soil health and the abundance of micro-organisms that play a positive role in plant development:
Organic farming
Organic farming avoids excessive use of chemical pesticides and fertilisers, which preserves the microbial ecology of the soil.
Crop rotation
Changing crops season after season encourages microbial diversity and avoids the build-up of specific pathogens.
Use of cover crops
Maintaining a vegetative cover on the soil throughout the year helps to maintain microbial activity and prevent erosion.
Composting
Adding organic compost to the soil enriches the microbial population and provides nutrients in a balanced way.
Reduced tillage
Minimising soil tillage reduces the disruption of microorganisms in their natural environment.
Use of green manures
Planting green manure crops such as legumes can increase nitrogen fixation and enrich the soil in nutrients.
Soil health is fundamental to agricultural sustainability and global food supply. Beneficial microorganisms, working in symbiosis with plants, play an essential role in preserving that health. As a society, we must recognise the importance of
these tiny creatures and adopt practices that promote their thirving in our soils.
At CARTIF, we have the experience gained through the implementation of several projects related to the proper management of microbiology applied to agriculture and especially to soils, either in the form of biofertiliser (SUSTRATEC proejct) or in the form of biopesticide (SUPERA project).
Maintaining soil health is not only essential to ensure abundant and nutritous harvests, but also to preserve biodiversity and mitigate climate change. By protecting and nurturing life in the soil, we are investing in a healthier and more sustainable future for our planet and future generations. Let us care for the land that cares for us.