A quarter of all greenhouse gas emissions come from agriculture. Factory farming and extreme use of fertilizers and pesticides pollute our air, pollute our water and destroy our soil. Every year, 24 billion tons of fertile soil are lost worldwide. In Spain, two-thirds of the country is affected by desertification. But there are also soils further north that are similarly desolate. In this episode of Roots, science journalist Pierre Girard meets Remedios Arres in Andalusia and Johanna Häger in Brandenburg, the sandbox of Europe.

In France, in the Massif Central, Sarah Singla practices conservation agriculture based on three principles: minimal soil disturbance, permanent land cover and crop rotation. In Périgord, Benoît Le Baube also protects his fields by no longer plowing them. He also uses organic waste to fertilize the soil.

In this episode, we discover with the journalist Pierre Girard how cows can make the activity of a farm more respectful of nature and how sheep can improve cereal harvests. These unusual methods could offer a solution to agriculture's carbon emissions problem.

Biodiversity is good for the environment but also for our taste buds. In Alsace, a winegrower practices "complantation", the mixing of several grape varieties on the same plot to avoid pesticides. In southern Italy, Mario relies on the coexistence of plants and livestock to enrich the biodiversity of his fields and produce a mozzarella with a unique taste.

The largest store of carbon besides the oceans is the soil. If only 0.4 percent more carbon could be put into the earth every year, the increase in greenhouse gas emissions would stop immediately. This is called carbon farming. But whether carbon goes into the soil or not is decided by agriculture. In this episode of Roots, science journalist Pierre Girard meets Félix Noblia in the Basque Country and Fabrice Desjours in Burgundy.Félix uses a special grazing system that actively stores carbon in the soil. Fabrice Desjours from Burgundy combines forgotten herbs, trees and plants to transform meadows into forest gardens where everything is edible.