Effects of land uses and associated disturbance regimes on soil microbial networks in Mediterranean Mountain area
Soil is an important reservoir of biodiversity, and its microbial communities play a key role in sustaining ecological functions essential for soil fertility and ecosystem stability; however, land use and management practices, such as grazing and mowing, can significantly influence the structure and functioning of these communities. The aim of this study was to assess the effects of the main land uses in the Matese mountain area (Mediterranean region) - pasture, meadow, and forest - with particular emphasis on the impacts of the associated management practices, namely grazing in pasture and mowing in meadow, on soil microbial activity, diversity, and community interactions. Soil physico-chemical parameters, microbial biomass, enzymatic activities involved in major biogeochemical cycles, and microbial diversity were analyzed. In addition, microbial co-occurrence networks analysis was performed to investigate network complexity and patterns of microbial interactions. Forest soil exhibited higher microbial biomass, enzymatic activity, and more complex microbial co-occurrence networks, reflecting a more stable ecosystem. In contrast, pasture and meadow soils showed reduced microbial networks complexity, suggesting that management-related disturbances influence microbial interactions. Despite this, meadow soil maintained high microbial diversity; this pattern is consistent with the intermediate disturbance hypothesis, which predicts that moderate levels of disturbance can favour species coexistence by reducing competition. Overall, these results highlight that the adopted management practices and disturbance regimes contribute to maintaining microbial biodiversity and ecosystem functional stability.