Climate change is threatening mountain grasslands and their cultural ecosystem services

Mountain grasslands are widespread ecosystems worldwide that provide economic and cultural ecosystem services. They serve as a source of food, carbon sequestration, clean water, and habitat, also hosting traditional practices such as transhumance. However, they are facing growing threats due to climate change, including extreme weather events like intensified rainfall causing soil erosion and prolonged droughts alongside high temperatures, impacting vegetation health and water resource management. Despite their strategic importance, there remains a gap in the comprehensive global mapping of these ecosystems and an exhaustive exploration of the critical challenges posed by climate change. In this context, we present an unprecedented satellite-based global mapping of mountain grasslands and conduct an analysis focusing on key climate change-related concerns. This includes an assessment of (1) soil erosion by water under diverse climate scenarios (RUSLE; 2015 vs. 2070-RCP8.5) and (2) the dynamics of extreme drought and high-temperature events (utilizing the Vegetation Health Index; VHI), with a specific focus on European mountain grasslands during the summer of 2022. Our findings indicate a potential future global aggravation of soil erosion in mountain grasslands (+2.3%), particularly in South America (+19.4%) and Africa (+10.0%), as well as localized hotspots. Furthermore, our analysis of the 2022 situation in Europe demonstrates the extensive impact of similar extreme events across a significant portion of grassland areas at a continental scale, with notable hotspots observed in southern Europe. Finally, we explore strategies to enhance mountain grassland management, specifically focusing on nature-based solutions (NbS) aimed at preserving their invaluable cultural ecosystem services in the face of climate change.