An extraordinary abundance and diversity of microorganisms inhabit soil and contribute to many ecosystem services that soil provides to humans, such as those related to agricultural production and environmental quality. Both theoretical analysis and empirical data generally support the view that the microbial diversity of soil is critical to sustain plant health and ecosystem productivity (Bell et al., 2009; Saleem et al., 2019; Wagg et al., 2021). The positive relationship between the microbial diversity of soil and ecosystem functioning has been documented by most studies using controlled experiments, although such a clear relationship cannot be easily revealed by direct examination of natural ecosystems (Bell et al., 2009).