Ecosystems

, Volume 16, Issue 6, pp 1013–1024

Vegetation and Soil 15N Natural Abundance in Alpine Grasslands on the Tibetan Plateau: Patterns and Implications

  • Yuanhe Yang
  • Chengjun Ji
  • David Robinson
  • Biao Zhu
  • Huajun Fang
  • Haihua Shen
  • Jingyun Fang
Article

DOI: 10.1007/s10021-013-9664-1

Cite this article as:
Yang, Y., Ji, C., Robinson, D. et al. Ecosystems (2013) 16: 1013. doi:10.1007/s10021-013-9664-1

Abstract

The natural abundance of nitrogen (N) stable isotopes (δ15N) has the potential to enhance our understanding of the ecosystem N cycle at large spatial scales. However, vegetation and soil δ15N patterns along climatic and edaphic gradients have not yet been fully understood, particularly for high-altitude ecosystems. Here we determined vegetation and soil δ15N in alpine grasslands on the Tibetan Plateau by conducting four consecutive regional surveys during 2001–2004, and then examined their relationships with both climatic and edaphic variables. Our results showed that both vegetation and soil N in Tibetan alpine grasslands were more 15N-enriched than global averages. Vegetation δ15N did not exhibit any significant trend along the temperature gradient, but decreased significantly with an increase in precipitation amount. In contrast, soil δ15N did not vary with either mean annual temperature or precipitation. Our results also indicated that soil δ15N exhibited a slight increase with clay content, but decreased with soil carbon:nitrogen ratio. A general linear model analysis revealed that variations in vegetation δ15N were dominantly determined by climatic variables, whereas soil δ15N was related to edaphic variables. These results provide clues for potential climatic and edaphic regulations on ecosystem N cycle in these high-altitude regions.

Keywords

carbon:nitrogen ratio climate isotope nitrogen cycle soil δ15soil texture vegetation δ15

Supplementary material

10021_2013_9664_MOESM1_ESM.docx (453 kb)
Supplementary material 1 (DOCX 454 kb)

Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  • Yuanhe Yang
    • 1
    • 2
  • Chengjun Ji
    • 2
  • David Robinson
    • 3
  • Biao Zhu
    • 4
  • Huajun Fang
    • 5
  • Haihua Shen
    • 1
  • Jingyun Fang
    • 1
    • 2
  1. 1.State Key Laboratory of Vegetation and Environmental Change, Institute of BotanyChinese Academy of SciencesBeijingChina
  2. 2.Department of Ecology, and Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijingChina
  3. 3.Institute of Biological and Environmental Science, School of Biological SciencesUniversity of AberdeenAberdeenUK
  4. 4.Department of HorticultureCornell UniversityIthacaUSA
  5. 5.Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina