Composition and diversity of arbuscular mycorrhizal fungal communities associated with planted Mediterranean hedgerows. AM fungi in hedgerows

Promoting sustainable agriculture is essential to address global challenges such as climate change and biodiversity loss. Planting hedgerows is proven to be an effective tool for promoting aboveground biodiversity and providing ecosystem services. However, little is known about their impact on belowground biodiversity. Arbuscular mycorrhizal (AM) fungi are one of the key components of belowground biodiversity. The present work compared the composition and diversity of AM fungal communities in planted Mediterranean hedgerows with adjacent habitats. From four sites in Central Spain, 120 samples were collected to quantify soil physical and chemical properties and analyse AM fungal metabarcoding data. Several biodiversity metrics were used to fit linear models and compared soil physical and chemical properties and AM fungal communities in hedgerows, olive groves, vineyards, barley field, and pastureland. We found that hedgerows increased AM fungal richness and diversity, particularly with respect to herbaceous agricultural habitat. Wooded habitats increased AM fungal abundance and were associated with higher proportions of soil carbon, pointing to their contribution to the ecosystem service of carbon sequestration. They were also related to a higher proportion of non-ruderal taxa, showing potential to restore lost belowground functional diversity. We suggest that European farmers should plant more hedgerows to restore belowground biodiversity and attain the goals of the EU Biodiversity Strategy for 2030.