Emission of CO2, CH4 and N2O from lakeshore soils in an Antarctic dry valley

E. G. Gregorich*, D. W. Hopkins, B. Elberling, A. D. Sparrow, P. Novis, L. G. Greenfield, P. Rochette

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

72 Citations (Scopus)

Abstract

We measured soil profile concentrations and emission of CO2, CH4 and N2O from soils along a lakeshore in Garwood Valley, Antarctica, to assess the extent and biogeochemical significance of biogenic gas emission to C and N cycling processes. Simultaneous emission of all three gases from the same site indicated that aerobic and anaerobic processes occurred in different layers or different parts of each soil profile. The day and location of high gas concentrations in the soil profile corresponded to those having high gas emission, but the pattern of concentration with depth in the soil profile was not consistent across sites. That the highest gas concentrations were not always in the deepest soil layer suggests either limited production or gas diffusion in the deeper layers. Emission of CO2 was as high as 47 μmol m-2 min-1 and was strongly related to soil temperature. Soil respiration differed significantly according to location on the lakeshore, suggesting that factors other than environmental variables, such as the amount and availability of O2 and nutrients, play an important role in C mineralization processes in these soils. High surface emission (maximum: 15 μmol m-2 min-1) and profile gas concentration (maximum: 5780 μL L-1) of CH4 were at levels comparable to those in resource-rich temperate ecosystems, indicating an active indigenous population of methanogenic organisms. Emission of N2O was low and highly variable, but the presence of this gas and NO3 in some of the soils suggest that denitrification and nitrification occur there. No significant relationships between N2O emission and environmental variables were found. It appears that considerable C and N turnover occurs in the lakeshore soils, and accurate accounting will require measurements of aerobic and anaerobic mineralization. The production and emission of biogenic gases confirm the importance of these soils as hotspots of biological activity in the dry valleys and probable reservoirs of biological diversity. Crown

Original languageEnglish
Pages (from-to)3120-3129
Number of pages10
JournalSoil Biology and Biochemistry
Volume38
Issue number10
DOIs
Publication statusPrint publication - Oct 2006
Externally publishedYes

Keywords

  • Antarctic dry valleys
  • Biogenic gases
  • Carbon dioxide
  • Gas emission
  • Methane
  • Microbial mat
  • Mineralization
  • Nitrous oxide
  • Polar desert

Fingerprint

Dive into the research topics of 'Emission of CO<sub>2</sub>, CH<sub>4</sub> and N<sub>2</sub>O from lakeshore soils in an Antarctic dry valley'. Together they form a unique fingerprint.

Cite this