Earthworm ecology in northern European forests

Forests cover roughly 35% of Europe’s land area and are mostly managed, with around 75% of the total forested area available for wood supply, and 24% in protected areas (Forest Europe 2020). Forest composition varies greatly across the continent, including conifer-dominated boreal forests in Northern countries, mixed forests in Central-Western Europe and greater dominance of broadleaved trees in South-Western countries. Earthworms play an important ecological and biogeochemical role in European forest ecosystems, driving litter decomposition and acting as key bioturbators, but also steering soil properties. In this chapter, we bring a new perspective to earthworm ecology in forest ecosystems, with a focus on European temperate and boreal forests. We explore large-scale (including non-native earthworms) and small-scale (microhabitat) heterogeneities, discuss how global threats (e.g. climate and land-use change) can reshape our forests and their earthworm communities and include important considerations for future research into earthworm ecology in forest systems.