Spatiotemporal patterns of soil myxomycetes in subtropical managed forests and their potential interactions with bacteria.

Soil myxomycetes are crucial soil protists with important ecological functions. Yet, our understanding of their diversity patterns in managed forests and the interactions with their food is far behind other taxa. This study investigates the spatiotemporal patterns of soil myxomycetes in four northern subtropical managed forest types across seasons and aims to identify assembly processes, main predictors of myxomycete communities, and the potential interactions between myxomycetes and bacteria. Results showed that no significant difference in α diversity of myxomycete communities among forest types was observed, but a significant difference was observed in community structures. Significant differences were observed in α diversity and community structures of myxomycetes among seasons. Deterministic processes in each forest type and season dominated myxomycete community assemblies. Soil physicochemical properties and bacterial communities have a significant direct impact on the myxomycete community, while forest types, seasons, and enzyme activities have an indirect effect. There is a significant synergistic covariation between the soil myxomycete community and bacterial community. The genera of the phyla Acidobacteriota, Actinobacteriota, and Bacteroidota have a strong correlation with the richness of myxomycete genera. Overall, this study provides new insight into the diversity of soil myxomycetes and their influence by bacteria, crucial for myxomycetes ecology.IMPORTANCESoil myxomycetes are an important component of soil protists. Our study revealed for the first time the community structure of soil myxomycetes in managed forests of the northern subtropical regions and systematically investigated the seasonal variation patterns of soil myxomycetes. Meanwhile, we further investigated the potential interactions between soil myxomycetes and bacteria. This study will greatly enhance our understanding of the ecology of soil myxomycetes and their biological roles.