DOI: 10.5061/dryad.1ns1rn95g
title: Nutrient availability and invader density regulate the diversity–invasibility relationship mediated by soil microbes

description: This dataset accompanies a study examining how native plant diversity,
 nutrient availability, and invader density interact to influence the
 growth of the invasive plant Phytolacca americana via soil microbial
 mechanisms in a temperate forest ecosystem. The dataset includes (1)
 aboveground biomass data of P. americana grown in soils conditioned by
 varying native plant diversity levels (1, 3, or 6 species), under
 different nutrient conditions (fertilized vs. non-fertilized) and invader
 planting densities (1, 2, or 4 individuals); and (2) soil fungal community
 data derived from high-throughput sequencing, including taxonomic profiles
 (from phylum to genus) and functional classifications assigned using
 FUNGuild (e.g., saprotrophs, pathogens, symbionts). These data support
 analyses of how plant–soil feedbacks and soil microbial composition
 mediate invasion success, and are valuable for researchers in the fields
 of invasion ecology, soil microbiology, and plant–microbe interactions.
description: # Nutrient availability and invader density regulate the
 diversity–invasibility relationship mediated by soil microbes Dataset DOI:
 [10.5061/dryad.1ns1rn95g](10.5061/dryad.1ns1rn95g) ## Description of the
 data and file structure This dataset contains measurements of aboveground
 biomass of the invasive plant *Phytolacca americana* and fungal community
 composition from soil samples collected under varying diversity
 treatments. The experiment manipulated native plant diversity, nutrient
 availability, and invader density to examine their interactive effects on
 plant invasibility and soil microbial dynamics. #### Methodological
 information We collected plant samples manually, oven-dried them, and
 weighed the dry biomass using an electronic balance to obtain plant
 biomass data. We isolated the total genomic DNA from 250 mg of each
 homogenized soil sample using the EZNA® Soil DNA Kit (Omega Bio-tek,
 Norcross, GA, USA) and quantified DNA concentrations using a NanoDrop2000
 spectrophotometer (Thermo Fisher Scientific, Waltham, MA, USA). The
 primers ITS1/ITS2 were used to amplify the ITS1 region to obtain data on
 soil fungal communities. #### Files and variables **File**:
 Li_et_al.__plant_biomass.xlsx **Variables** * **Id**: Row number for each
 data entry. * **Diversity**: The level of native plant diversity in the
 treatment, with three levels: 1, 3, and 6 species. * **Identity**: The
 identity of the native species used in the diversity-1 treatment, and the
 specific species combinations used in the diversity-3 and diversity-6
 treatments. A total of 27 unique combinations were used. * **Density**:
 The number of *Phytolacca americana* individuals (invader density) planted
 per pot, with three levels: 1, 2, or 4 plants. * **Nutrient**: Nutrient
 availability treatment, where 1 indicates fertilised and 2 indicates
 non-fertilised conditions. * **Biomass**: The aboveground dry mass (in
 grams) of *Phytolacca americana* per pot, measured after oven-drying and
 weighing. **File:** Li_et_al.__Fungi.xlsx **Variables** * **OTU**:
 Operational Taxonomic Unit; a unique identifier for a cluster of similar
 fungal ITS sequences, typically approximating species-level resolution. *
 **sample1–sample27**: Columns representing individual experimental soil
 samples. Each cell indicates the number of ITS sequence reads (i.e.,
 abundance) assigned to a particular OTU in a given sample. * **Taxonomy**:
 Microbial taxonomic classification (e.g., phylum, class, order, family,
 genus) assigned to each OTU based on ITS sequence similarity. * **Taxon**:
 The scientific name of the fungal taxon assigned to each OTU, based on ITS
 classification. * **Taxon Level**: The taxonomic rank at which the OTU was
 assigned. * **Trophic Mode**: The primary ecological strategy of the
 fungus (e.g., saprotroph, symbiotroph, pathotroph), as defined by the
 FUNGuild database. * **Guild**: The predicted ecological role or function
 of the fungal taxon (e.g., saprotroph, pathogen, endophyte), assigned
 based on FUNGuild classification. * **Growth Morphology**: The general
 growth form of the fungus. * **Trait**: Functional or ecological traits
 associated with the fungal taxon, such as host specificity, substrate
 preference, or ecological niche. * **Confidence Ranking**: A qualitative
 indicator of confidence in the trophic/guild assignment (e.g., “Probable”,
 “Highly Probable”, or “Possible”), as provided by FUNGuild or other
 sources. * **Notes**: Additional notes or clarifications regarding
 specific OTUs or functional assignments. This may include manual
 annotations, classification uncertainties, or contextual ecological
 information. * **Citation/Source**: The literature or database used as the
 source for taxonomic or functional annotation. Note: For all columns
 (except *Notes*), cells containing “–” indicate missing or unavailable
 data. This may be due to low sequence similarity, ambiguous taxonomy, or
 lack of functional annotation in reference databases. **Data was derived
 from the following sources:** Data was derived from the following sources:
 plant biomass data were manually recorded during the experiment, while
 soil microbial community data were generated by Meiji BioTech Co., Ltd.
 through high-throughput sequencing and analysis.