The numbers of the water emergency and the thermal collapse of soils
Desertification must not be confused with the natural and geographical expansion of existing deserts. From a scientific and agronomic perspective, the term describes the progressive degradation of soils in arid, semi-arid, and dry sub-humid zones, caused primarily by global climate variations and unsustainable anthropogenic activities. This silent, creeping phenomenon is transforming once-fertile and biologically active territories into unproductive wastelands, incapable of sustaining plant life, retaining rainwater, or hosting the complex microbial trophic networks that form the foundation of terrestrial ecosystems. The severity of this transformation has reached critical proportions, prompting the scientific community to issue categorical warnings regarding the planet’s future food sustenance capabilities.
Today, the Mediterranean Sea basin represents one of the primary global climate hotspots, a region where warming is proceeding at a rate 20% faster than the planetary average. Analyses conducted by major institutions and reported by ASviS (Italian Alliance for Sustainable Development) outline an unambiguous picture: Italy recorded 2024 as the hottest year ever documented since historical measurements began. These consecutive thermal records do not merely raise seasonal averages; they profoundly alter soil thermodynamics and the hydrological balance. Rising temperatures dramatically accelerate evapotranspiration, the combined process through which moisture physically evaporates from the Earth’s surface and is biologically transpired by plant leaves. When the evapotranspiration rate chronically exceeds rainfall inputs, profound agronomic and hydrological drought is triggered.
Under this thermal stress scenario, precipitation undergoes extreme polarization. Long months of summer and autumn drought are interrupted by rainfall of unprecedented intensity—so-called cloudbursts or water bombs. However, degraded and parched soil develops a physical condition known as hydrophobicity, or water repellency. The surface, hardened and devoid of porosity, acts like an asphalt slab: instead of slowly absorbing and filtering rainwater to recharge underground aquifers, the terrain rejects it, generating rapid and destructive surface runoff. This mechanism strips away the superficial arable layer (topsoil), rich in minerals and nutrients, dragging it into rivers and the sea, and triggering devastating landslides, mudslides, and floods in downstream areas.
Soil physics: from organic matter loss to hydrogeological instability
To understand the root causes of desertification in Europe and worldwide, it is necessary to analyze the agricultural and land-management models adopted over the last century. Intensive industrial agriculture has based its productivity on three practices deeply harmful to the physics and biology of the earth: deep mechanical tillage (such as plowing), monoculture, and the abuse of synthetic chemical inputs (fertilizers, herbicides, and pesticides). Continuous plowing and exposing bare soil to weathering and solar radiation mechanically destroy soil aggregates and accelerate the oxidation of trapped organic carbon. This carbon is released into the atmosphere as carbon dioxide (CO2), further aggravating the greenhouse effect.
A healthy soil consists of approximately 50% empty spaces (pores) filled with air and water, and the remaining 50% mineral particles (sand, silt, clay) and organic matter. Although organic matter represents only a fraction between 1% and 5% in optimal agricultural soils, it is the true engine of hydrological resilience. It acts like a microscopic sponge capable of retaining an amount of water equal to twenty times its own weight. Intensive agriculture has systematically depleted this carbonaceous fraction, bringing European soils to organic matter levels below 1%, the clinical threshold for pre-desertification.
Furthermore, bare soils possess a low albedo effect: they absorb massive amounts of solar radiation, raising the microclimatic temperature at ground level to over 50 degrees Celsius during the summer months. At these temperatures, the microbial life (bacteria, mycorrhizal fungi, nematodes) that guarantees nutrient availability to roots is literally sterilized. The collapse of soil microbiology interrupts the biogeochemical cycles of nitrogen and phosphorus, making crops chronically dependent on the artificial supply of chemical fertilizers, which, in turn, increase soil salinization, closing a vicious circle of progressive territorial sterilization.
Nature-Based Solutions (NBS) and Ecological Engineering
Reversing this catastrophic desertification process requires a radical paradigm shift in territorial and rural planning. The United Nations and environmental protection agencies urgently promote the adoption of Nature-Based Solutions (NBS)—ecological engineering interventions that leverage natural mechanisms to restore original ecosystem functions. Instead of fighting water or drought with massive reinforced concrete infrastructure (dams, artificial drainage canals), NBS aim to redesign the landscape to maximize water retention distributed across the territory.
One of the most effective techniques within NBS is Keyline Design, a topographical approach involving soil cultivation and planting along precise contour lines of the land. This conformation intercepts, slows down, and allows rainwater to infiltrate via capillary action into the subsoil, preventing surface runoff and distributing moisture evenly even in the driest zones of a hillside. Retention trenches (swales) act as temporary accumulation basins, creating humid microclimates where trees and shrubs are planted to stabilize the slopes.
Concurrently, strategic reforestation and agroforestry combine the cultivation of agricultural species with the growth of timber or fruit trees within the same plot. Trees act as windbreaks, reducing evaporation caused by dry air currents, and provide vital shade that drastically lowers soil temperature. Their deep roots act as biological hydraulic pumps, bringing moisture and minerals from deep soil layers to the surface (hydraulic lift), making them available for adjacent herbaceous crops as well. This complex vegetative layer recreates a diverse habitat that attracts pollinators, birdlife, and natural predators of agricultural pests, reducing the need for chemical pesticides.
Regenerative agriculture as a shield against desertification
At the core of the revolution against aridity and land degradation is regenerative agriculture—a holistic set of agronomic practices that surpass the mere concept of “sustainability” (maintaining the status quo) to aim for the active, measurable rehabilitation of degraded ecosystems. The principles of regenerative agriculture are clear, scientifically grounded, and readily applicable: eliminating or drastically reducing mechanical tillage (no-till farming), maintaining constant vegetative cover (cover crops), diversifying crop rotations, and holistically integrating animal grazing.
The no-till technique leaves the complex subterranean architecture created by earthworms and mycorrhizal fungal networks intact, ensuring optimal water infiltration and preventing carbon oxidation. The uninterrupted use of cover crops (such as legumes and grasses planted between commercial cash crops) ensures the soil is never bare: leaves protect the earth from the kinetic impact of raindrops and direct insolation, while living roots continually pump sugars and exudates into the soil, feeding the microfauna.
An additional innovative element for restoring marginal soils is the use of biochar (vegetal charcoal). Produced through the pyrolysis of agricultural and forestry waste, biochar is a highly porous and chemically inert material. Incorporated into the soil, it acts like an underground coral reef: its microscopic cavities retain water, host beneficial microorganisms, and prevent nutrient leaching, ensuring prolonged fertility and sequestering solid carbon in the ground for centuries. This significantly contributes to the fight against climate change.
June 17th and the global governance of resources
The complex and urgent challenges related to soil and water management converge emblematically on June 17th, the date on which the World Day to Combat Desertification and Drought is celebrated. Established by the United Nations General Assembly in 1994, this day aims to raise global public awareness and alert policymakers to the urgency of implementing Goal 15 of the 2030 Agenda (Protect, restore, and promote the sustainable use of terrestrial ecosystems, sustainably manage forests, combat desertification, and halt and reverse land degradation).
This anniversary is not a mere commemorative exercise but a political call for collective action. Countering the advance of desertification requires courageous governance at all institutional levels: from economic support for farmers transitioning to regenerative practices to the adoption of rigorous National Climate Change Adaptation Plans. Europe has taken significant steps with the Nature Restoration Law directives, but implementation across individual territories requires overcoming resistance from major agrochemical lobbies.
In conclusion, drought and desertification are not inescapable punishments from nature, but the physical, tangible symptoms of an obsolete territorial exploitation model incompatible with the Earth’s biophysical limits. As citizens, our capacity to mitigate this emergency passes through precise choices: from supporting local, regenerative agricultural supply chains to fighting food waste and mindfully consuming water. Soil is not simply an inert substrate upon which to build our cities, but the living, fragile, and indispensable epidermis of our planet. Healing the earth, returning organic matter to it, and protecting it from mechanical and chemical devastation is the only true vaccine at our disposal to ensure global climate stability and guarantee a prosperous, fertile, and safe future for generations to come.
