Fungal community structure and network connectivity as indicators of soil health under long-term land use

Agriculture practices induce profound changes in soil biological properties and soil functioning. However, we still lack an understanding of how soil fungal biodiversity responds to various practices. Metagenomic tools were used to investigate soil fungal communities and inferred ecological functions based on functional guild classification in response to the effect of climate region and land management. This study assessed how seasonal timing and long-term land management affect soil fungal communities, with the aim of exploring their potential as candidate indicators of soil biological status. We collected soil samples across two regions of Israel (Mediterranean north and semi-arid south), three land-use types—orchard (OR), field crops (FC), and non-cultivated control (CO)—and two seasons—autumn and spring. Abiotic parameters varied significantly by season, region, and depth, underscoring the importance of considering sampling time in soil assessment. Fungal community composition showed marked differences between land uses, suggesting sensitivity to long-term management. CO and OR soils consistently exhibited higher fungal diversity and network connectivity, while FC soils had lower richness and unique taxa. A stable core community of 10 genera was found across treatments. Functional guilds were dominated by saprotrophs, though specific taxa and guild contributions varied by management type and season. Overall, our results emphasize the importance of sampling timing and land-use history in shaping fungal communities and support the potential of fungal-based indicators for assessing soil status across agricultural systems.