Soil health and diversity are central to Drôme Valley’s agroecological strategies facing climate and sustainability challenges.

Authors: Mathilde Chomel & Christian Icard (with the support of the Solvi’Terra team)

The Drôme Valley has a rich and unique history, shaped by a long-standing tradition of welcoming newcomers. Over the centuries, people from diverse backgrounds, often seeking a fresh start, have settled here. Their presence has helped keep villages vibrant, boosting both the local economy and the cultural and social life of the region.

Yet, the valley’s true strength lies in the exceptional quality of its natural environment and the deep commitment of its people to protect it. As early as the 1980s, local institutions began mapping and analysing agricultural soils to better understand how to manage them sustainably. The Agricultural Atlas of the Drôme (1982), based on the 1979–80 general agricultural census, provided a detailed picture of land use, laying the groundwork for future efforts to protect and enhance these vital resources.

Building on this foundation, the Communauté de Communes du Val de Drôme (CCVD) initiated a comprehensive agro-pedological mapping project, involving around 400 soil analyses across the region. This effort aimed to identify and classify the diverse soil types present, setting the stage for decades of collaborative work. Local authorities, residents, and farmers have joined forces to revitalise the land and waterways, including significant efforts to restore the Drôme River, which is now clean, swimmable, and one of Europe’s last wild rivers. 

The Chambre d’agriculture de la Drôme (CA26) further supports these efforts through initiatives like the TYPTERRE project, or animations of groups on soil conservation agriculture, which helps farmers optimize soil management and land use planning.  

Agriculture in the valley has embraced principles of regeneration and resilience, becoming part of the Biovallée initiative. For over 30 years, this bioregion has united local stakeholders in their efforts to drive ecological transition. Soil health and biodiversity lie at the heart of farming practices, supported by public programs like agro-environmental and climate action plans, as well as territorial pastoral initiatives. These efforts have led to impressive results, with 30% of farms now certified organic. The region has become a model for agroecology. 

This context fostered the installation of local actors like AgriBioDrôme, les Alvéoles, Permalab, FiBL France, GRAB and ADAF, who promote soil health through organic farming, agroforestry, and permaculture, experimenting with low-input techniques, compost systems, and tree integration to enhance soil fertility and resilience. These organizations also provide advisory support, training programs on soil health, and collaborate with local stakeholders to implement innovative agricultural techniques. Their collective efforts make soil a central pillar of the region’s agroecological transition.

However, challenges remain. A projected increase in evapotranspiration, combined with reduced rainfall and rising droughts, threatens the future sustainability of agriculture in the area. For several years, farmers have faced drought conditions and strict water access restrictions. Meanwhile, the loss of organic matter and soil degradation continues, exacerbating the impact of these climatic events and reducing the long-term viability of the agricultural system.

The activities in the Val de Drôme are closely aligned with the European Soil Mission, one of the EU’s five Horizon Europe missions aiming to deliver tangible benefits by 2030. The Soil Mission’s core objective is to ensure that 75% of soils in the EU are healthy and able to provide essential ecosystem services by the end of the decade. It emphasizes restoring soil health as a foundation for food security, climate regulation, biodiversity conservation, and human well-being. The main goal of the Mission ‘A Soil Deal for Europe’ is to establish 100 living labs and lighthouses to lead the transition towards healthy soils by 2030.

In this context, the GOV4ALL project, funded under the Soil Mission framework, contributes to this ambition by supporting multi-actor governance models that empower local stakeholders to co-design soil monitoring and management strategies. These efforts not only serve regional needs but also feed into a Europe-wide data and knowledge base, strengthening collective capacity to address soil degradation and climate resilience at the European level.

The Solvi’Terra Living Lab, created within the GOV4ALL project, brings fresh momentum to promote changes in farming practices aimed at improving soil health and increasing the resilience and sustainability of farms in the Val de Drôme.

One of the actions involves conducting 120 soil analyses on LUCAS grid points across the CCVD territory, with 95 points on agricultural lands / moors and 25 in forests. FiBL France, Chambre d’agriculture de la Drôme and GRAB are joining efforts to sample and analyse those samples. This initiative will help the EU to monitor soil health at the European level, and at the local level will allow researchers to compare the current data with previous analyses from 1986, offering insights into soil evolution in the last 40 years.

This task has been more challenging than expected, first to get the contact details of landowners or farmers, and second due to tight windows of optimum sampling conditions (i.e. without recent fertilisation/amendment or tillage). For now, about 40 points have been sampled, and the sampling will spread over 2025 in the objectives to have a complete dataset in early 2026. 

The Val de Drôme is distinguished by its diversity of soils, shaped by the varied geography of the region, stretching from the plains of the Rhône Valley to the foothills of the Vercors. This diversity can be summarised in four main types of cultivated soil (Figure 3): 

• Alluvial soils: Found along the Drôme and Rhône rivers, these fertile soils, rich in river-deposited sediments, are ideal for crops like cereals, oilseeds, and legumes. However, they are highly sensitive to compaction. 

• Sandy-clay loam soils: Common on old terraces along the Rhône Valley, these soils, often containing a high proportion of stones, strike a good balance between drainage and water retention, making them well-suited for fruit tree cultivation. 

• Calcareous sandy soils: Found in certain hilly areas of the Drôme, these soils are prone to erosion, have low organic matter, and do not retain water well, posing challenges for crop production. 

• Limestone and clayey soils: Predominantly found in the hilly and mountainous regions of the Vercors, these calcium-rich soils, often rocky, are ideal for viticulture and Mediterranean crops. However, their high calcareous content can bind nutrients like phosphorus, boron, and iron, making them inaccessible to plants. In areas without rocks, these heavy, poorly drained soils require specific farming techniques, such as improved drainage and moisture management. 

LUCAS soil sampling by Christian Icard, FiBL France (Photo: M. Chomel,/iBL France)