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Biogeochemistry

, Volume 120, Issue 1–3, pp 1–21 | Cite as

Reconstructing terrestrial nutrient cycling using stable nitrogen isotopes in wood

  • Laci M. Gerhart
  • Kendra K. McLauchlan
Synthesis and Emerging Ideas

Abstract

Although recent anthropogenic effects on the global nitrogen (N) cycle have been significant, the consequences of increased anthropogenic N on terrestrial ecosystems are unclear. Studies of the impact of increased reactive N on forest ecosystems—impacts on hydrologic and gaseous loss pathways, retention capacity, and even net primary productivity—have been particularly limited by a lack of long-term baseline biogeochemical data. Stable nitrogen isotope analysis (ratio of 15N to 14N, termed δ15N) of wood chronologies offers the potential to address changes in ecosystem N cycling on millennial timescales and across broad geographic regions. Currently, nearly 50 studies have been published utilizing wood δ15N records; however, there are significant differences in study design and data interpretation. Here, we identify four categories of wood δ15N studies, summarize the common themes and primary findings of each category, identify gaps in the spatial and temporal scope of current wood δ15N chronologies, and synthesize methodological frameworks for future research by presenting eight suggestions for common methodological approaches and enhanced integration across studies. Wood δ15N records have the potential to provide valuable information for interpreting modern biogeochemical cycling. This review serves to advance the utility of this technique for long-term biogeochemical reconstructions.

Keywords

Nitrogen availability Dendrochronology δ15Dendroecology Tree rings Nitrogen deposition 

Notes

Acknowledgments

This work was funded in part by the National Science Foundation under grant NSF-DEB 1145815 to K.M. We thank members of the Novus Network for helpful discussions, and Joe Craine and Julie Commerford for technical assistance.

Supplementary material

10533_2014_9988_MOESM1_ESM.pdf (103 kb)
Supplementary material 1 (PDF 102 kb)

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© Springer International Publishing Switzerland 2014

Authors and Affiliations

  1. 1.Department of GeographyKansas State UniversityManhattanUSA

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