Asynchronous pulse responses of soil carbon and nitrogen mineralization to rewetting events at a short-term: Regulation by microbes

Sci Rep. 2017 Aug 8;7(1):7492. doi: 10.1038/s41598-017-07744-1.

Abstract

Rewetting after precipitation events plays an important role in regulating soil carbon (C) and nitrogen (N) turnover processes in arid and semiarid ecosystems. Here, we conducted a 48-h rewetting simulation experiment with measurements of soil C and N mineralization rates (R C and R N, respectively) and microbial biomass N (MBN) at high temporal resolution to explore the pulse responses of R C and R N. R C and R N responded strongly and rapidly to rewetting over the short term. The maximum R C value (because of pulse effects) ranged from 16.53 to 19.33 µg C gsoil-1 h-1, observed 10 min after rewetting. The maximum R N varied from 22.86 to 40.87 µg N gsoil-1 h-1, appearing 5-6 h after rewetting. The responses of soil microbial growth to rewetting were rapid, and the maximum MBN was observed 2-3 h after rewetting. Unexpectedly, there was no correlation between R C, R N, and MBN during the process of rewetting, and R C and R N were uncoupled. In sum, the pulse responses of R C, R N, and microbial growth to simulated rewetting were rapid, strong, and asynchronous, which offers insights into the different responses of microbes to rewetting and mechanisms behind microbes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biomass
  • Carbon / chemistry*
  • China
  • Desert Climate
  • Ecosystem
  • Microbial Consortia / physiology*
  • Models, Statistical
  • Nitrogen / chemistry*
  • Soil / chemistry*
  • Soil Microbiology*
  • Water / chemistry*

Substances

  • Soil
  • Water
  • Carbon
  • Nitrogen