There are two anniversaries a year related to soil conservation, one is today. Is this resource so important?
Actually, International Soil Conservation Day, which is celebrated on July 7, began to be commemorated in 1963 thanks to Hugh Hammond Bennett, a pioneer in the defense of soil health, who insisted on the importance of this resource to prevent degradation and increase agricultural productivity. Many years have passed and yet it barely had an impact until relatively recently. Until the early 2000s there was no real concern about the importance of land. The soil is directly related to our health: more than 95% of the food we consume is produced in it. If we want quality food, we need healthy soil. In addition, it is home to more than 25% of the planet’s biodiversity. If we want to conserve this biodiversity, and for this we have a European directive, we have to protect the soil. It also acts as a carbon reservoir; If we protect it, we will also contribute to improving air quality.
What has changed from the year 2000 until now?
In 2000, an attempt was made to approve a directive, but in the end it did not go ahead and in 2014 it was withdrawn. Fortunately, in 2021 the European Union presented the Strategy for Soil Protection until 2030. But note that we are talking about 2021. And it was not until 2025 when the Directive on Soil Monitoring and Resilience was approved, which for the first time provides Europe with a legal framework to protect soils. As you can see, it has taken a long time to take action.
How are our soils?
Unfortunately, very degraded. The FAO indicates that 33% of the planet’s soils are already degraded and warns that, if we do not act, in 2050 that figure could reach 90%. In the European Union, data indicate that between 60 and 70% of soils present some type of degradation. In the case of agricultural soils, the percentage is close to 80%. We have to try to reverse this process and stop it, because the soil is losing its functions and there may come a time when it stops being productive as it is so degraded that it can no longer continue to provide food.
What is the solution?
The directive that I have mentioned establishes that we must know the state of our soils, properly manage those that are contaminated and promote sustainable agricultural practices, because agriculture is one of the main causes of degradation. Good management is essential. Many current practices, such as fertilization, can become a source of pollution and emissions. Farmers needed to increase production and, to do so, the fertilizer industry emerged. However, a large part of the fertilizers applied are not used by plants: they are lost, contaminate the soil and generate emissions into the atmosphere.
All the legislative development in recent years seeks precisely to manage the soil in a sustainable way, reduce the use of fertilizers and apply only the amount that the crops really need to avoid subsequent contamination. But, in addition to the chemical degradation caused by excess fertilizers, physical-chemical degradation can also occur if we do not incorporate organic matter into the soil, even if we do not use mineral fertilizers. The soil can lose its ability to retain water and increase erosion problems caused by wind or rain. If we protect the soil against these processes we will prevent its degradation. To do this, we must apply sustainable practices, such as increasing the contribution of organic matter and combining mineral fertilization, only when necessary, with organic fertilization. What we need is to increase the resilience of the soil.
So it still has a fix?
Yes, of course it does. Obviously, we could have started earlier, but fortunately today we have many more means and knowledge to know how to act.
Could the fertilizer price crisis be a good opportunity to get to work?
Now we have an opportunity thanks to the circular economy strategy. There is a lot of organic matter that, if applied appropriately and rationally, can help reduce dependence on mineral fertilizers. Spain depends heavily on fertilizers from Morocco, Algeria and other Eastern European countries. With the war, prices have skyrocketed. Furthermore, as I said, we must try to reduce the quantities we apply, at least between 20 and 30%.
I think we are at the right time to do it. We have legislation, and that is very important. The directive approved in 2025 now gives all Member States three years to begin monitoring their soils, knowing their condition, detecting whether they are contaminated, improving their management and, in the case of agricultural soils, promoting more sustainable practices through the use of organic matter, reducing mineral fertilization and promoting quality crops that guarantee food security.
What difficulties can farmers have?
Now, for example, they have to record everything they apply to the soil. They must keep a field notebook in which they write down what fertilizers they use and in what doses, in addition to having technical advice. A lot of advice is needed for farmers to use these products correctly. If we want to promote sustainable practices, we must also provide the means necessary to carry them out.
How long can it take for degraded soil to recover and become fertile again? Are they very long processes?
Yes, they are long processes. It depends on each case, but if we want to recover soil in a sustainable way we can be talking about months or even years.
What are we facing if we do not act?
To lose the capacity to produce food, to accelerate desertification processes and to suffer more floods. When soil degrades, it loses resilience and is much more vulnerable to extreme events.
What are they doing at IMIDRA?
In the Contaminated Soils Area we study and evaluate different decontamination techniques that are sustainable and that we can apply without impairing the functionality of the soil. There are many techniques to decontaminate, but many are very aggressive. We can eliminate pollution and, at the same time, leave soil incapable of developing its functions. At IMIDRA we try to identify effective techniques that respect these functions. They are less aggressive methods, based on the use of microorganisms, plants or nanoparticles. Each technique has its particularities and limitations; Not all of them are suitable for any type of soil, so it is necessary to study each case individually. On the other hand, from an agricultural point of view, we investigate what sources of organic matter can be incorporated into the soil to reduce the use of mineral fertilizers. We are also evaluating nanofertilizers that are already used in countries such as the United States and India.