Abstract
Atmospheric nitrogen (N) deposition reduces plant diversity. However, it often remains unclear how dominant species and litter accumulation feedbacks mediate N-induced plant diversity declines. We tested mechanisms of N-induced diversity change through dominant grasses and litter in a 7-year field experiment. Nitrogen addition reduced species richness, Shannon–Wiener diversity (H′) and evenness from the second to the fourth year, however, surprisingly, increased them in the sixth and seventh year. The reversal in the response of diversity to N addition was explained by changes in grass dominance and standing litter accumulation. The diversity recovery during later years in fertilized plots was attributed to a decrease in the dominant grass and an increase in standing litter: standing litter reduced bud numbers of the dominant grass by decreasing light availability. The decreased light availability by standing litter reduced completion from the dominant species, which resulted in diversity increase. The negative feedback between dominant grasses and standing litter led to transient N-induced diversity loss in the short-term, but recovery of plant diversity in the long-term. Grassland management that affects litter accumulation, such as firing, grazing and mowing, can therefore, have substantial effects on the long-term response of plant diversity to N deposition.
Original language | English (US) |
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Pages (from-to) | 921-929 |
Number of pages | 9 |
Journal | Oecologia |
Volume | 188 |
Issue number | 3 |
DOIs | |
State | Published - Nov 1 2018 |
Bibliographical note
Funding Information:cal suggestions by Dr. Eric G. Lamb. This project was supported by the National Key Research and Development Program of China (2016YFC0500602), the National Natural Science Foundation of China (31770520, 31230012, 31302012), the Program for Introducing Talents to Universities (B16011) and the Program for Innovative Research Team in University (IRT-16R11).
Publisher Copyright:
© 2018, Springer-Verlag GmbH Germany, part of Springer Nature.
Keywords
- Competition exclusion
- Diversity loss
- Eutrophication
- Nitrogen deposition
- Species interactions