Call summary :

Scope and expected outcomes

Activities under this topic will help to progress towards the objectives of the Mission ‘A Soil Deal for Europe’. Activities will also contribute to the EU Biodiversity Strategy for 2030 and the Nature Restoration Law, to the EU Soil Strategy for 2030 and the proposed Soil Monitoring and Resilience Directive, EU Water Framework Directive, as well as the EU Action Plan on the Development of Organic Production.

Project results are expected to significantly contribute to all the following outcomes:
- Enhance stakeholders’ (including decision-makers’ and land managers’) understanding of the importance that soil-water interactions play in mitigating risks associated with extreme events such as droughts, wildfires and floods and their virulence.
- Raise stakeholders’ awareness of the relevance of soil biodiversity232 to soil characteristics (e.g. water retention capacity, permeability, saturation, etc.) which are relevant for the soil-water nexus.
- Substantially contribute to increasing environmental resilience to extreme events like floods, droughts, or wildfires, as well as to other undesired soil health processes, through restoration, conservation and integrated management of the soil-water nexus.

Scope: The world is facing an increasing trend in the frequency and virulence of extreme events like droughts, wildfires, and floods, with soil, and more precisely soil-water interactions, playing a key role in their occurrence and impact. A holistic response is necessary to face these events and better manage the risks and impacts they create onto the environment, food security, the economy and human security.

For example, recent studies have shown the significance of soil moisture in wildfire probability and virulence233, the importance of soil-water retention capacity and availability for vegetation and crop possibilities to endure droughts, and the potential for improved retention and infiltration to reduce flood peak flow and its destructive effects234. Soils, sediments, and water are intimately connected, as soils filter, absorb and buffer water, but can also get eroded and contaminated through water. Healthy soils can help mitigate not only the occurrence, virulence and scope of extreme events, but also other undesired processes like erosion or contamination. But when soils are unhealthy, compacted or sealed, they lose capacity to absorb and store water, which reduces their capability to mitigate the risks and impacts of extreme events.

While soil biodiversity plays an important role with respect to soil properties such as porosity, aggregation or organic matter content, its influence on water dynamics is often complex and indirect, and thus still poorly studied. Therefore, it is necessary to enhance the understanding of the functional role of soil biodiversity for soil-water dynamics, and to develop and validate new models for mainstreaming and integrating soil biodiversity together with other risk assessment parameters.

Proposed activities should:
- Develop and validate one or more indicators for the soil water holding capacity descriptor included in the proposed Soil Monitoring Law, considering the different pedoclimatic areas and land uses in the EU and Associated Countries.
- Identify the soil properties and associated indicators (e.g., structure, bulk density, porosity, depth, organic matter, buffering etc.) and factors (e.g., slope, frost, cover, drainage network, etc.) that determine soil-water dynamics and are relevant for the probability and virulence of extreme events. The use of remote sensing techniques is encouraged for soil factors identification.
- Assess the role of soil biodiversity for the previously identified water-relevant soil properties and the impact of the different soil factors on soil biodiversity, considering different pedoclimatic areas and land uses in the EU and Associated Countries. Where relevant, involve soil biodiversity taxonomists to validate methods and expand knowledge.
- Develop and validate new models (or substantially improve existing ones) at watershed/landscape level that mainstream and integrate the functional role of soil biodiversity in soil-water interactions and specially in risk assessment of extreme events.
- Assess and validate strategies and best practices proposed in the context of other relevant EU-funded projects and initiatives (e.g. Living Labs funded under the EU Mission “A Soil Deal for Europe”235 or the Horizon Europe projects SpongeBoost and SpongeScapes) to increase environmental resilience by improving the soil-water nexus through restoration, conservation and management of soil and its biodiversity, considering the different pedoclimatic areas and land uses in the EU and Associated Countries.
...