Impact of bioclimate and substrate-driven variations on trophic groups of soil nematodes in Moroccan olive orchards

Olive trees are known for their wide adaptability and consistent production trends in Mediterranean countries. As a result, they host a diverse range of soil nematodes that shape the overall microbiome, and grow in a variety of different soil types (substrates) and bioclimatic conditions. This study examined the interactions between soil nematode communities and various soil types in Moroccan olive orchards, which are characterized by distinct Mediterranean bioclimates ranging from Saharan to subhumid. The research was conducted across five major olive-growing regions, with three representative orchards selected from each bioclimatic zone and substrate type to ensure variability in soil type, elevation, and management practices. Advanced modeling techniques were employed to analyze the relationships between nematode parameters and climatic/edaphic factors, revealing significant positive and negative associations. Additionally, the results indicated that nematode diversity and trophic structure were influenced by soil type, mineral content, organic matter, and climatic variables such as mean annual precipitation and temperature. The findings highlighted the importance of understanding these interactions for sustainable olive orchard management and emphasized their active linkage to soil health attributes operated by nematode communities, thus providing a foundation for future studies aimed at enhancing soil ecosystem services in the context of climate change.