Ecological renaturation of poor soils and valorization of embankments - Objectives and implementation

Climate change and the loss of biodiversity are major challenges facing our planet and the societies that inhabit it. Many experts now link the climate emergency to the collapse of biodiversity. This is because the goal is twofold: to save nature for its own sake and to preserve a living environment and resources that allow human populations to survive and thrive.

The good health of ecosystems and soils, and their sound conservation status, ensure an abundant supply of high-quality water, fertile land, and natural spaces. In temperate Europe, heavily vegetated ecosystems perform numerous functions, particularly climate regulation, and help combat climate disruption through evapotranspiration, the replenishment of aquifers, the buffering of surface water, and the recycling and storage of carbon in wood and soil. To a certain extent, it is vegetation that shapes the climate, not the climate that shapes vegetation.

The ecological functions of ecosystems, when humans derive benefits from them, become ecosystem services (services provided). These services fall into the categories of production (raw materials, drinking water, food, textiles, wood, biomass, energy), regulation (flood control, drought mitigation, pest control, etc.), or cultural enjoyment (places for walking and hiking, nature exploration, sports, art, well-being, culture, spirituality, religion, fishing, etc.). Preserving and restoring ecosystems appears to be an essential means of safeguarding our productive spaces and preventing territorial inequalities—and thus, in the long term, avoiding geopolitical tensions between countries, regions, or communities of stakeholders and residents within the same territory; and to prevent mass migration of populations to fertile areas when their original habitats have become “unproductive” spaces, deserts, or are submerged. We must be able to take action at all levels, regardless of our areas of expertise.

That is why, before addressing the issue of renaturation, it is important to reiterate the importance of preserving what already exists : avoid destruction before considering restoration, renaturation, or compensation. Interventions must follow the ERC-R or ERC-A sequence (avoid, reduce, and compensate—or even forgo or support) regardless of the type of actions or impacts. Conducting a naturalist survey over a minimum of one year (a four-season survey) is an essential prerequisite...