Desertification, soil and climate change
Desertification is an environmental process, greatly accelerated by human activities and the resulting climate change, which leads to soil degradation, the loss of the biosphere (animal and plant) and the transformation of the environment into a desert.
According to a 2018 study by the European Commission, more than 75% of the world's soil is already degraded to some degree. This percentage, already extremely high, could reach 90% by 2050. Every year, 4.18 million square kilometres - around half the surface area of the European Union - are degraded.
Parallel to desertification is the loss of soil organic matter (MOS), which compromises the functionality and fertility of agricultural soils. MOS consists of substances of plant or animal origin that decompose in the soil through the action of microorganisms. It is a fundamental component for fertility, biodiversity and the functioning of terrestrial ecosystems. MOS performs multiple functions, including improving soil structure and stability, increasing water retention capacity and resistance to climatic stresses, providing nutrients to plants, enhancing soil biodiversity, improving ecological functions essential for maintaining the planet's natural balance, participating in regulating the carbon cycle and mitigating climate change through carbon sequestration.
In agriculture, MOS is threatened by several degradation factors, including intensive and unsustainable agricultural practices. These practices can cause a loss of MOS through various mechanisms, including: intensification of soil tillage, reduction in inputs of stabilised organic matter, such as inadequately matured slurry from livestock farms and biodigesters, excessive or inappropriate use of synthetic fertilisers and pesticides, such as insecticides and herbicides.
The experiment: Regenerating the soil at Villa Fortuna
The experimentation was set up to validate innovative and classic methods to regenerate the land of Villa Fortuna, owned by the Capellino Foundation in San Salvatore Monferrato (AL), where the soil has been impoverished by years of intensive cultivation. During the first few years of the project, an Agroforestry system was set up, a mixed cultivation system that intersperses fruit trees with forest trees and shrubs, which, in addition to bringing back biodiversity, had the primary task of giving stability to the soil and starting to reverse the highly degraded state of the land, protecting it from complete exposure to the weather, which further accelerated its erosion, making it impossible to set up structured regenerative practices. Intensive soil tillage, such as deep ploughing, was discontinued and replaced by minimal tillage and continuous soil cover by mulching (covering the soil with organic material to protect it from the weather) and sowing herbaceous plants in all inter-row areas for continuous plant cover.
Once we reach the third year of vegetation growth, we will be able to set up a scientific study to validate, by means of the right local and laboratory analyses, which stabilised soil conditioner is the best to accelerate soil regeneration through the adequate supply of organic matter in the soil. In the spring, different types of soil conditioners will be distributed in the soil, including compost, bokashi (a type of organic fermented product), and compost mixed with naturally occurring molecules, such as pectin, which will be responsible for enhancing different soil characteristics, including the ability to stimulate natural plant defence against disease, water retention, and the proliferation of microorganisms beneficial to crops and soil quality. In parallel, various cover crops will also be tested, which together with the soil improver will provide vitality and additional stability to the soil.
The same types of soil conditioners tested in the field will also be produced in a controlled environment and analysed chemically to provide a complete characterisation of these compounds and their properties.
The extensive monitoring, characterisation and aggregation of scientific data, which will extend over at least two years, implemented on both chemical parameters and the presence and evolution of soil microorganisms, will allow the main problems and advantages of the adopted practices to be highlighted and the formulation of a standard that clarifies which is the best agricultural practice for accelerated soil restoration.