Soil is much more than mere dirt. We refer to soil as the surface of the earth or the foundation for other activities, but it is so much more. It is where everything begins.
Soil plays an essential role in planetary balance. Plants and animals (including ourselves), agriculture, and even the climate depend on it because of its important job as a carbon sink.
The Delicate Layer That Sustains Us
Soil is the most delicate and superficial layer of planet earth. It is the result of thousands of years of interaction between the four terrestrial spheres (hydrosphere, lithosphere, atmosphere, and biosphere). It is 50% composed of solid materials, while the other half consists of the porous space, where air, water, and nutrients circulate and can be retained.
It is considered a non-renewable resource on a human scale, due to its formation time, limited thickness, and fragility. According to the FAO, it can take up to 1,000 years just to produce 2-3 cm of soil. Additionally, it boasts great biological richness. Although partially invisible, soil stores one quarter of our planet’s biodiversity. At a depth of only a few dozen centimetres lies a highly complex and diverse ecosystem that allows other larger ecosystems to develop.
Thanks to this biodiversity, organic matter is recycled in the soil and biogeochemical cycles are renewed . Through this process, well-managed soils store carbon and prevent the emission of greenhouse gases, thus helping to mitigate climate change and adapt to it.
The thing is that our survival and well-being depend on soil. Over 95% of the food we consume and a large part of the medications we use come from it. What is more, healthy soil guarantees drinkable water, since this is the first filter that water goes through. It also facilitates water’s arrival to the deep layers and recharges aquifers through its pores.
Endangered Soils
The formation of soil occurs at a speed that is inversely proportional to the rate of its degradation. According to the UNESCO, 75% of the planet’s soil is already degraded, affecting 3.2 billion people. If current trends remain, this percentage will reach 90% by 2050. This degradation, the first step in desertification, often begins with the elimination of natural plant cover as a result of deforestation, fires, or overgrazing. Once laid bare, the soil is more vulnerable to erosion from the wind and precipitation, especially with torrential rains, which makes these episodes much more dangerous.
In addition to their contribution to erosion, other activities such as agriculture, industry, and transport release pollutants that can accumulate in the ground and then travel to underground waters or crops. While not as well-known as ocean pollution, plastic and microplastic pollution in the soil is another one of the great environmental challenges we face today.
Protecting What Protects Us
Striving for living soil is clearly an investment in the future, even more so considering demographic and climate trends, which posit that agricultural production must increase by 60% to meet worldwide food demand in 2050. Having carbon sinks that work toward climate neutrality is a necessity.
Legislative measures to protect and restore them, following the model set forth by the Soil Strategy for 2030, promote sustainable use, avoid additional use of new lands, and improve fertility through practises associated, for example, with the circular economy. To control and monitor them, we are using technologies supported by satellites and drones.
At the same time, large-scale nature-based solutions, like the Great Green Wall, or local solutions such as phytoremediation (capturing or breaking down pollutants through crops) and municipal or domestic composting help to restore soils.
The scientific and agricultural research that is enabling innovation in soil use and care are worthy of mention. In dealing with intensive agriculture, which can reduce the availability of fertile soil, which is essential for continued production, regenerative agriculture is a must. This includes respectful practises, such as crop rotation and intercropping, flower strips, organic amendments, and green covers. These practises aim not only to preserve agricultural soil, but to improve it. All together, these measures could lead to an average increase in crop yield of 58%, according to the FAO.
Only adequate soil management will keep it healthy and productive, limiting its degradation and fostering its restoration to the benefit of all of us who live on this delicate layer that sustains us.
