“Soil is not a renewable resource, but a heritage asset” — Jean Guiony, President of the Institut de la Transition Foncière

Jean Guiony : The idea for the ITF emerged in 2022 from the observation that there was no industry bringing stakeholders together around soil-related issues, nor any standard technical and economic model on the subject, unlike other sectors such as energy or water. This gap was particularly evident during discussions around ZAN (Net Zero Land Take).

We sensed a clear willingness among stakeholders from different backgrounds to move forward on land-use efficiency. The first step was therefore to produce a manifesto, published in 2023. “Transition Foncière” was built around a shared voice, bringing together people who had previously had only conflictual relationships.

Building on this momentum, we were able to remind people that soils are volumes, not surfaces; that they are living rather than fossil matter; that they must be observed in cross-section rather than on a map; that they are not a renewable resource, but a heritage asset…

The ITF, which now has 27 members and three funding partners (the OFB [French Biodiversity Office], Ademe and Banque des Territoires), was thus created to support a change in perspective on these issues. They are far from self-evident for all those—developers, real estate developers, urban planners and others—who nevertheless work with soils every day and are increasingly affected by the ecological risks disrupting the development of cities and regions. Examples include the 8,000 of France’s 36,000 municipalities that, in 2022, declared a natural disaster related to clay shrink-swell, or certain towns in the Var department that refused all building permits in 2023, including valid ones, because of soil drought and water shortages… Ecological risk therefore directly affects real estate stakeholders, who are being driven to change their practices, in addition to the regulatory changes and land scarcity that also constrain them. They must adopt a new paradigm, shifting from the concept of land as a real estate asset to that of living soil.

Jean Guiony : To move from the concept of land as a real estate asset to living soil, the first step is to recognize that what we handle is a volume with vertical and ecosystem integrity, extending from bedrock to the air. If this continuity is broken, it is no longer living soil. It is also worth recalling that soils have seven ecological functions. The Climate and Resilience Act lists four, which can be divided into further functions and potentials : a climate function for carbon storage, a water function for regulating the water cycle, a biodiversity-support function, and an agronomic function for biomass potential (the remaining three concern the functions of filtering, buffering and degrading pollutants; interaction with the chemical composition of the atmosphere; and retaining and supplying nutrients, editor’s note) . The aim is to move from an economic and legal approach to an ecosystem-based approach—that is, to consider soil as a multifunctional, natural and non-renewable element.

Jean Guiony : Our first role is research and knowledge transfer, through a chair whose partners include Gustave Eiffel University, Caisse des Dépôts et Consignation, the ENSA Paris-Est school of architecture, and EIVP (the City of Paris engineering school). The aim of this chair is to give professionals access to scientific knowledge and build bridges between two scientific worlds: that of agronomists and soil scientists, and that of legal experts, land specialists, economists and planners. In this context, we organize two scientific conferences a year, which result in scientific publications, and support doctoral students within real estate companies.

We also serve as an incubator for practical tools and studies, with the participation of our five stakeholder groups (companies; the State and its major agencies; local authorities; research and academia; civil society and environmental advocacy associations). Workshops are set up under the supervision of researchers. The ITF provides deliverables at different stages in the design of tools, and we develop use cases among our members. For example, we are seeking to create a reference framework for soil restoration techniques.

Our third role is advocacy with official bodies, informed by our other two roles.

Jean Guiony : It is interesting to examine the relationship between construction and soil through the lens of logistics projects, as they represent one of the greatest challenges in this area. Traditionally, this sector builds on a single level, at low density, and has experienced fairly strong economic growth in recent decades. It is a sector with a dual nature. On the one hand, relative to its density, it is a major contributor to soil sealing; on the other, it is the sector that covers the greatest number of miles. The potential gains from greater efficiency are therefore very significant. We can see all the efforts being made to build upward, develop alternative energy sources, use land that has already been developed, and so on. It still needs to address soil restoration, by unsealing soils on existing sites, using permeable materials that are more respectful of soils, and lifting regulatory constraints that prevent project sponsors from adopting construction methods that are more respectful of soils. For example, the requirement to provide a certain number of parking spaces forces project sponsors to develop more land than the project would otherwise require… In 2025, we will be working specifically on construction methods with a smaller land footprint, focusing in particular on building foundations.

Jean Guiony : Training is essential. Simply talking about what soil is, how it works and so on already generates tremendous interest and questions among these stakeholders. In addition, everyone who is trained becomes an ambassador for the cause. In my view, training should even be a form of moral obligation for anyone who has an impact on soil.

To support them, it is also essential to experiment and demonstrate what can be done. We can adjust the economic model to make land-use efficiency less costly, or even less costly than land development.

Compared with issues such as water or carbon, we are truly only at the beginning, and examples of possible alternatives are still lacking.