Scientific Indicators and Stakeholders' Perceptions on Soil Threats in France: How Do They Compare?

Abstract

Soils are under multiple threats, with varying levels of intensity and nature across different areas. It is therefore important to assess the soil threat level. To do so, scientific indicators have been developed, but their implementation at the country level can be challenging. As stakeholders have good knowledge of soil conditions, stakeholders' perceptions on soil threats could be used as a complementary indicator. The objective of this paper is to explore this possibility focusing on the five soil threats considered by stakeholders as the most important at the European level: erosion, artificialisation, compaction, soil organic carbon (SOC) loss and contamination. A participatory stakeholder consultation conducted in France in 2021 yielded 1444 responses. We elaborated stakeholders' perception maps at the departmental scale, which we compared with scientific indicator maps per soil threat. Our findings indicate that stakeholders consider artificialisation the most important soil threat in France. The spatial distribution of soil threats based on stakeholders' perceptions and scientific indicators matches in 43% of the departments for SOC loss, and in over half of the departments for erosion (50%), compaction (51%), artificialisation (63%) and contamination (74%). The differences can be attributed to higher stakeholders' perception compared to scientific indicators for erosion, SOC loss and contamination. Conversely, for artificialisation and compaction, these differences can be attributed to lower stakeholders' perception than the scientific indicators. Moreover, certain scientific indicators assess the threat only partially, whereas stakeholders may perceive the threat differently or as a whole. When biases in the scientific assessment, stakeholders' perception or comparison are taken into consideration, stakeholders' perceptions can be used as a tool to complement existing scientific indicators.