New soil carbon sequestration with nitrogen enrichment: a meta-analysis

Xiaomin Huang, César Terrer, Feike A. Dijkstra, Bruce A. Hungate, Weijian Zhang, Kees Jan van Groenigen

Research output: Contribution to journalArticle

Abstract

Background and aims: Through agriculture and industry, humans are increasing the deposition and availability of nitrogen (N) in ecosystems worldwide. Carbon (C) isotope tracers provide useful insights into soil C dynamics, as they allow to study soil C pools of different ages. We evaluated to what extent N enrichment affects soil C dynamics in experiments that applied C isotope tracers. Methods: Using meta-analysis, we synthesized data from 35 published papers. We made a distinction between “new C” and “old C” stocks, i.e., soil C derived from plant C input since the start of the isotopic enrichment, or unlabeled, pre-existing soil C. Results: Averaged across studies, N addition increased new soil C stocks (+30.3%), total soil C stocks (+6.1%) and soil C input proxies (+30.7%). Although N addition had no overall, average, effect on old soil C stocks and old soil C respiration, old soil C stocks increased with the amount of N added and respiration of old soil C declined. Nitrogen-induced effects on new soil C and soil C input both decreased with the amount of extraneous N added in control treatments. Conclusion: Although our findings require additional confirmation from long-term field experiments, our analysis provides isotopic evidence that N addition stimulates soil C storage both by increasing soil C input and (at high N rates) by decreasing decomposition of old soil C. Furthermore, we demonstrate that the widely reported saturating response of plant growth to N enrichment also applies to new soil C storage.

Original languageEnglish (US)
JournalPlant and Soil
DOIs
StateAccepted/In press - 2020

Keywords

  • Isotopes
  • Nitrogen addition
  • Nitrogen saturation
  • Soil carbon dynamics
  • Soil carbon input

ASJC Scopus subject areas

  • Soil Science
  • Plant Science

Fingerprint Dive into the research topics of 'New soil carbon sequestration with nitrogen enrichment: a meta-analysis'. Together they form a unique fingerprint.

  • Cite this

    Huang, X., Terrer, C., Dijkstra, F. A., Hungate, B. A., Zhang, W., & van Groenigen, K. J. (Accepted/In press). New soil carbon sequestration with nitrogen enrichment: a meta-analysis. Plant and Soil. https://doi.org/10.1007/s11104-020-04617-x