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08:44
Microplot Design and Plant and Soil Sample Preparation for 15Nitrogen Analysis
Published on: May 10, 2020
Nitrogen enrichment and plant communities.
Elsa E Cleland1, W Stanley Harpole
1Ecology, Behavior and Evolution Section, University of California San Diego, La Jolla California, USA. ecleland@ucsd.edu
Annals of the New York Academy of Sciences
|June 12, 2010
Summary
Global nitrogen (N) enrichment reduces plant species richness and alters community composition. Ecosystem N inputs can worsen limitations by other resources like phosphorus (P), and biotic factors like consumers also influence plant communities.
Area of Science:
- Ecology
- Environmental Science
- Plant Community Dynamics
Background:
- Anthropogenic nitrogen (N) enrichment is a global phenomenon impacting terrestrial ecosystems.
- Nitrogen is traditionally viewed as the primary limiting nutrient for plant growth.
- Recent research indicates widespread colimitation by other resources and biotic factors.
Purpose of the Study:
- To synthesize current understanding of plant community responses to nitrogen enrichment.
- To highlight the roles of colimitation by other resources (e.g., phosphorus) and biotic interactions (e.g., consumers, pathogens).
- To emphasize the importance of environmental and biotic contexts in N enrichment effects.
Main Methods:
- Review of observational and experimental studies on nitrogen enrichment.
- Synthesis of theoretical predictions and recent synthetic research.
- Analysis of factors influencing plant community structure.
Main Results:
- Nitrogen enrichment frequently leads to declines in species richness and increased primary production.
- Species composition is reordered, with shifts in species gains/losses, dominance, and functional groups.
- Disproportionate N input exacerbates limitations by other resources like phosphorus (P).
- Consumers and pathogens play significant roles in determining plant community structure.
Conclusions:
- Plant community responses to nitrogen enrichment are complex and context-dependent.
- Colimitation by multiple resources and biotic interactions are critical factors.
- Understanding these broader contexts is essential for predicting ecosystem responses to N enrichment.
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