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Updated: May 18, 2026
08:05
Measurement of the Potential Rates of Dissimilatory Nitrate Reduction to Ammonium Based on 14NH4+/15NH4+ Analyses via Sequential Conversion to N2O
Published on: October 7, 2020
Nitrogen addition regulates soil nematode community composition through ammonium suppression.
Cunzheng Wei1, Huifen Zheng, Qi Li
1State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China. weicunzheng@ibcas.ac.cn
Plos One
|September 7, 2012
Summary
Nitrogen enrichment reduces soil nematode abundance and diversity in grasslands. Ammonium toxicity impacts nematode richness and trophic groups, affecting the soil food web.
Area of Science:
- Soil ecology
- Ecosystem functioning
- Environmental science
Background:
- Anthropogenic nitrogen (N) enrichment alters soil communities.
- Nematodes are key soil organisms and indicators of ecosystem health.
- Understanding nematode responses to N enrichment is crucial for grassland management.
Purpose of the Study:
- To investigate the temporal dynamics of soil nematode communities under N enrichment.
- To explore the mechanisms regulating nematode responses to N enrichment using structural equation modeling.
- To assess the impact of N enrichment on nematode trophic groups and their interactions.
Main Methods:
- A multi-level N addition experiment was conducted in an Inner Mongolia grassland.
- Soil nematode communities were monitored over three years.
- Structural equation modeling (SEM) was used to analyze nematode responses and environmental factors.
Main Results:
- N enrichment significantly reduced total nematode abundance, diversity, and key trophic groups (root herbivores, fungivores, omnivores-predators).
- Ammonium concentration negatively correlated with nematode richness and trophic group composition, explaining substantial variation.
- Bacterivores exhibited a hump-shaped response to N addition, while fungivore abundance positively correlated with fungal biomarkers.
Conclusions:
- Nitrogen enrichment profoundly impacts soil nematode communities in semiarid grasslands.
- Ammonium toxicity is a significant factor regulating nematode richness and structure.
- Findings highlight cascading effects on the detrital soil food web and the importance of nematodes as ecological indicators.
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