J Plant Ecol ›› 2019, Vol. 12 ›› Issue (6): 1025-1033 .DOI: 10.1093/jpe/rtz036

• Research Articles • Previous Articles     Next Articles

Impacts of nitrogen deposition on terrestrial plant diversity: a meta-analysis in China

Wen-Juan Han1, Jia-Yu Cao1, Jin-Liang Liu2,3, Jia Jiang1 and Jian Ni1,*   

  1. 1College of Chemistry and Life Sciences, Zhejiang Normal University, 321004 Jinhua, China
    2College of Life and Environmental Science, Wenzhou University, 325035 Wenzhou, China
    3College of Life Sciences, Zhejiang University, 310058 Hangzhou, China
    *Correspondence address. College of Chemistry and Life Sciences, Zhejiang Normal University, 688 Yinbin Avenue, Jinhua, 321004, China. Tel: +86 579 82287521; Fax: +86 579 82287521; E-mail: nijian@zjnu.edu.cn
  • Received:2019-04-01 Revised:2019-06-19 Accepted:2019-07-01 Published:2019-12-01

Abstract:

Aims

With the global atmospheric nitrogen (N) deposition increasing, the effect of N deposition on terrestrial plant diversity has been widely studied. Some studies have reviewed the effects of N deposition on plant species diversity; however, all studies addressed the effects of N deposition on plant community focused on species richness in specific ecosystem. There is a need for a systematic meta-analysis covering multiple dimensions of plant diversity in multiple climate zones and ecosystems types. Our goal was to quantify changes in species richness, evenness and uncertainty in plant communities in response to N addition across different environmental and experimental contexts.

Methods

We performed a meta-analysis of 623 experimental records published in English and Chinese journals to evaluate the response of terrestrial plant diversity to the experimental N addition in China. Three metrics were used to quantify the change in plant diversity: species richness (SR), evenness (Pielou index) uncertainty (Shannon index).

Important Findings

Results showed that (i) N addition negatively affected SR in temperate, Plateau zones and subtropical zone, but had no significant effect on Shannon index in subtropical zones; (ii) N addition decreased SR, Shannon index and Pielou index in grassland, and the negative effect of N addition on SR was stronger in forest than in grassland; (iii) N addition negatively affected plant diversity (SR, Shannon index and Pielou index) in the long term, whereas it did not affect plant diversity in the short term. Furthermore, the increase in N addition levels strengthened the negative effect of N deposition on plant diversity with long experiment duration; and (iv) the negative effect of ammonium nitrate (NH4NO3) addition on SR was stronger than that of urea (CO(NH2)2) addition, but the negative effect of NH4NO3 addition on Pielou index was weaker than that of CO(NH2)2 addition. Our results indicated that the effects of N addition on plant diversity varied depending on climate zones, ecosystem types, N addition levels, N type and experiment duration. This underlines the importance of integrating multiple dimensions of plant diversity and multiple factors into assessments of plant diversity to global environmental change.

Key words: species richness, Shannon index, Pielou index, nitrogen addition, meta-analysis