Integrating Morphological and Molecular Approaches for Assessing Soil Biodiversity in Agroecosystems

The One Health paradigm, emphasizing the interdependence of human, animal, and environmental health, demands a comprehensive approach for ecosystem monitoring. This study underscores the vulnerability of Mediterranean ecosystems to desertification and climate change, emphasizing the critical role of soil biodiversity in agroecosystems. Interdisciplinary collaboration is imperative to mitigate these challenges and foster a resilient balance between human, animal, and environmental well-being in the region. In this context, monitoring soil biodiversity, an essential component in ecosystem functioning, remains relatively understudied compared to above-ground organisms, posing conservation and management challenges. Depending on the land management practices, agroecosystems can pose a significant impact on various aspects of the environment, including soil biodiversity, food security, and the provision of essential ecosystem services. Molecular methods (e.g. barcoding, metabarcoding) offer promising results in assessing soil biodiversity more efficiently. This study addresses the problem of thoroughly evaluating soil macrofauna diversity in agroecosystems with differing management intensities; morphotaxonomy and metabarcoding methods were used to explore their validation and integration. In this study, we morphologically identified 9418 individuals, representing 13 taxonomic groups; metabarcoding identified more than 800 OTUs (Operational taxonomic Units) , belonging to seven different classes. Significantly higher levels of biodiversity were recorded in the traditional agroecosystems, while improved pastures had the lowest. Moreover, metabarcoding results showed that all sites differ significantly from each other regarding OTU communities, with a separation into two clusters: one encompassing extensively managed agroforests and another with intensive, hyperintense, and improved pastures agroecosystems. This study underscores the importance of an integrative approach that combines morphotaxonomy and molecular methods to improve species identification accuracy, shedding light on the potential of molecular techniques such as metabarcoding to provide fast and precise species identification. However, further refinement of molecular methods is still required, and collaboration between researchers and taxonomists is essential. The data gathered here might help define efficient management practices according to the different land-use types, to promote a sustainable balance between biodiversity and productivity. By adopting an integrative and interdisciplinary approach, we can better understand and conserve soil biodiversity in agroecosystems, ultimately contributing to a more sustainable and secure world.