The fourth MONTCLIMA transnational transfer seminar took place at the Bilbao conference centre.

During a little more than 4 hours, the 12 speakers of the day discussed some key aspects of soil protection strategies at European and regional level, two pilot tests on the subject that are being developed within the scope of MONTCLIMA and inspiring presentations on the potential of soils as carbon sinks and their role in mitigating climate change.

Block 1, on MONTCLIMA case studies for soil protection, featured a very inspiring introduction by Carlos Garbisu, scientific director of NEIKER. Carlos spoke about the inescapable link between the good state of soils and the health of the planet. The scientist argued that when we talk about soil health, we are referring to its functions and specifically to the ecosystem services it provides to humans. However, this concept has its limitations and there is also a lot of confusion between terms (functions, processes and services). "Vigour, organisation and resilience are more appropriate concepts to measure the health of any ecosystem," Carlos concluded.

The concept of rewilding emerges as a key alternative to mitigate the impacts of climate change and generally offset the effects of global change. It can be a viable strategy to ensure the functional integrity of ecosystems, so that they can develop their ecological processes and functions, on which the health of the planet depends.

Olatz Unamunzaga, NEIKER technician and head of the MONTCLIMA pilot case on erosion in vineyards, stated that in Europe, 60% of soils suffer some kind of degradation process. Some agronomic practices exacerbate water erosion problems, as is the case in the Rioja Alavesa, the geographical area where this MONTCLIMA pilot case is located. The aim of the trial presented by Olatz is to demonstrate the importance of plant cover to limit soil erosion, and its positive effects on the properties and production of vineyards. The scientist concluded, thanks to preliminary results from 2 seasons, that the use of spontaneous plant cover significantly reduces erosion compared to conventional tillage (8 times less soil loss). In conclusion, she insisted on the importance of field measurements to contrast and validate the results of the models.

Etienne Ebrard, from the ONF, presented the functioning of the experimental device deployed thanks to the MONTCLIMA project, aimed at estimating the behaviour of erosion risk and sediment dynamics after a major forest fire.

In this pilot case located in an eastern valley of the French Pyrenees, several 100m2 plots were selected to measure the erosion rate at different selected sites in an area affected by a major fire (municipality of Cerbère). After the first tests, preliminary results show that the plots affected by the fire show a more intense hydrological response. Erosion rates in the fire-affected areas are also generally 10 times higher than in the other areas.

Jordi Deu, from Andorra, presented the MONTCLIMA pilot case aimed at mitigating the effects of torrential lava flows upstream of a drinking water plant (Torrente de Claror). In this innovative case study, nature-based measures have been deployed by means of degradable dykes in the main gullies generated by water erosion. In addition, revegetation has also been carried out by sowing Festuca eskiaa species through natural fertilisation of the affected area previously prepared with the passage of livestock (a process called "ovinoremediation", according to the engineer). This combination of nature- based measures has proved effective in reducing the risk of erosion in this protected mountain area.

"Soil occupies less than 0.000002%, yet all of humanity depends on it".

Block 2, which focused on the presentation of key strategies for soil protection in the Southwest European area, demonstrated the growing importance of soil as a key issue within the European Commission.

Mirco Barbero, Coordinator of the Soil Protection and Sustainable Land Use Team, pointed out that around 60% of European soils are not healthy. He also reminded the audience of the latest developments on soil policy in Europe. In November 2022 the Commission adopted a new Soil Strategy. Furthermore, soil appears as a key and cross-cutting element in the European Green Deal. In this context, the European Soil Observatory is emerging as a key tool in the defence of soil health at European level. “The main objective of this strategy is to ensure that soil ecosystems are in good health by 2050, and to achieve this we must implement concrete actions that respond to the strategic objectives," said the European officer. This refers to cross- cutting actions on soils that address the issue of improving resilience, enhancing carbon neutrality and safeguarding biodiversity. He also confirmed to those present that the Commission is preparing the new soil law, but the lack of concrete definitions, indicators and threshold values is posing a challenge for this.

Loli Lorenzo, head of the soil area of Ihobe, explained the contents of the soil protection strategy of the Basque Country. Recently approved, this law bases its philosophy on the concept of soil health. "Soil preservation is a complex subject, very interdisciplinary and cross-cutting in terms of regulations and management strategies," confirmed the representative. Moreover, there is a confluence of overlapping interests, implying the need for a high degree of consensus, coordination and teamwork", the technician affirmed. On the other hand, it is undeniable that there is a certain complexity in transposing the general principles of the European commission's Soil Strategy into measurable and objective actions. Law 5/2015 of the Basque Country focuses on the correction of soil pollution, although the need to develop a comprehensive soil protection strategy has already been mentioned. The Basque Country strategy has 7 areas of action and 69 specific actions.