Speaker
Description
Nematodes are abundant and diverse in soil, influencing microbial community composition, plant performance, and nutrient cycling, and serving as vital bioindicators of soil ecology and health. While metabarcoding techniques have become highly standardized in the identification of microbial (i.e., bacterial and fungal) communities, similar techniques are still under development for soil animals. As metabarcoding techniques become increasingly popular for characterizing soil animals, establishing protocols that are adapted to larger-bodied organisms is necessary. To optimize nematode metabarcoding workflows, we assessed how different identification techniques and soil sample sizes influence estimates of nematode diversity, composition, and resulting nematode community indices. We compared three identification techniques: traditional morphological identification, and two molecular methods using either nematode-extracted DNA or total soil DNA, and tested each across a size gradient (0.25 g – 32 g soil). Sample mass and identification technique shaped community level soil nematode assessments. Increasing soil mass significantly increased taxonomic richness (q = 0) across all methods, while abundance-weighted diversity (q = 1, 2) remained largely unaffected. Morphological identification consistently recovered fewer genera than molecular approaches. Community variability was lowest in soil DNA datasets, and increasing soil mass further reduced variance, particularly for soil DNA and morphological approaches. Methodological differences strongly influenced ecological interpretation. For example, a higher Enrichment Index but a lower Channel Index were observed with the morphological approach than with others, while the Maturity and Structure Indices did not change. Our findings show that methodological choice primarily shapes community structure, while sample size refines detection and improves consistency. Both factors should be considered for reliable and comparable nematode assessments.
| Status Group | Doctoral Researcher |
|---|---|
| FOR TALKS: Poster Presentation Option | Yes, I’m willing to present as a poster. |