Competition mode and soil nutrient status shape the role of soil microbes in the diversity–invasibility relationship

Understanding the relationship between plant diversity and invasibility is essential in invasion ecology. Species-rich communities are hypothesized to be more resistant to invasions than species-poor communities. However, while soil microorganisms play a crucial role in regulating this diversity–invasibility relationship, the effects of plant competition mode and soil nutrient status on their role remain unclear. To address this, we conducted a two-stage greenhouse experiment. Soils were first conditioned by growing nine native species separately in them for 1 year, then mixed in various configurations with soils conditioned using one, three, or six species, respectively. Next, we inoculated the mixed soil into sterilized substrate soil and planted the alien species Rhus typhina and native species Ailanthus altissima as test plants. We set up two competition modes (intraspecific and interspecific) and two nutrient levels (fertilization using slow-release fertilizer and non-fertilization..., At 8 weeks after the start of the test phase, all aboveground and belowground parts of the test plants were harvested and rinsed with water. Owing to the death of some seedlings during the growth period, 502 R. typhina individuals (interspecific: 239, intraspecific: 263) and 259 A. altissima individuals were harvested. The collected plant tissue was placed in a 70 °C oven to dry for a week and was weighed. The biomass of two R. typhina plants was measured together under intraspecific competition, and the biomass of R. typhina and A. altissima was measured separately under interspecific competition.
Soil sampling, DNA extraction, amplicon sequencing, and bioinformatics analysis
The 27 mixed fresh soil samples, collected from various diversity treatments and subsequently stored in a refrigerator at −80 °C, were analyzed for soil fungal community composition. The total microbial community DNA was extracted according to the instructions of the E.Z.N.A. Soil DNA Kit (Omega Bio-tek, Norcross,..., , # Competition mode and soil nutrient status shape the role of soil microbes in the diversity–invasibility relationship

[https://doi.org/10.5061/dryad.wh70rxww6](https://doi.org/10.5061/dryad.wh70rxww6)

## Description of the data and file structure

Data usage bootstrap:

See plant biomass data at: Li et al.\_ plant biomass

See soil fungi community data at: Li et al.\_ Fungi

See soil FUNGuild function prediction at: Li et al.\_ FUN Guid

### DATA-SPECIFIC INFORMATION FOR: Li et al.\_ plant biomass

1\. Number of variables: 6

2\. Number of cases/rows: 763

3\. Variable List:

\"species\" refers to the classification of plants as either alien or native.

\"diversity\" refers to the level of plant diversity.

\"soil mixture types\" refers to the types of soil mixtures.

\"interspecific competition\" and \"intraspecific competition\" refer to the modes of competition.

\"fertilization\" and \"non-fertilization\" refer to the nutrient levels.

\"total biomass\" refers to the total plant biomass (g) unde...