A First Quantitative Assessment of Soil Health at European Scale Considering Soil Genesis

Background: Soil health degradation is a major threat to European food security, biodiversity, and climate stability. While scientists have debated how to define soil health during recent decades, a quantifiable framework for monitoring, management, and policy remains lacking. Aim: We introduce SHERPA (Soil Health Evaluation, Rating Protocol, and Assessment) as a framework for discussion and present a first quantitative soil health assessment across Europe. Methods: All major soil degradation processes (with the exception of organic contamination) were scored, averaged, and subtracted from the intrinsic soil health resulting in quantitative final scores. Results: As reported before, cropland soils throughout Europe are highly degraded. Surprisingly, soil health of grasslands is also very negatively impacted. Soil erosion, nutrient surplus, and pesticide risk are largely driving poor soil health aligning with reported high biodiversity loss in agricultural land. Forest soils are also surprisingly low in health, mainly because of nitrogen surplus, reflecting documented widespread forest decline from nutrient imbalances. Interactive maps highlight specific threats to soil health across Europe, offering valuable insights for targeted action. Conclusions: SHERPA is able to quantify soil health across Europe. However, at the current state of data availability, soil health is likely to be overestimated. Monitoring data of soil structure, compaction, pesticide spread and, in forest ecosystems, disturbance of humus layer are urgently needed for final assessment of soil health.