Plant-soil-microbe systems trades carbon (C) and nutrients and control the storage or release of these compounds. The intimate association of mycorrhizal fungi with plants facilitates plant nutrient provisioning, contributing to the decomposition and formation of soil organic matter (SOM). In temperate climates, dominating fungal guilds are arbuscular mycorrhizal fungi (AM), ectomycorrhizal fungi (ECM), and saprotrophic fungi (SAP). Although these fungi's distinct nutrient acquisition strategies influence nutrient cycling, SOM formation, and C and nutrient storage, the impacts of the diverse fungal guilds on these processes are still elusive. Hence, (i) the role of distinct fungal guilds on C and nutrient cycling and SOM formation and (ii) the nutrient acquisition of these fungi were investigated. For this, we applied the source and process information stable 13C and 15N isotopes possess, allowing to trace the origin and the fate of compounds. Collectively, this research supports the need to consider fungal guilds in predicting C and nutrient cycling and storage patterns in ecosystems.