Advertisement

Climatic Change

, Volume 44, Issue 1–2, pp 139–150 | Cite as

Annual CO2 Flux in Dry and Moist Arctic Tundra: Field Responses to Increases in Summer Temperatures and Winter Snow Depth

  • J. M. Welker
  • J. T. Fahnestock
  • M. H. Jones
Article

Abstract

We examined the annual exchange of CO2 between the atmosphere and moist tussock and dry heath tundra ecosystems (which together account for over one-third of the low arctic land area) under ambient field conditions and under increased winter snow deposition, increased summer temperatures, or both. Our results indicate that these two arctic tundra ecosystems were net annual sources of CO2 to the atmosphere from September 1994 to September 1996 under ambient weather conditions and under our three climate change scenarios. Carbon was lost from these ecosystems in both winter and summer, although the majority of CO2 evolution took place during the short summer. Our results indicate that (1) warmer summer temperatures will increase annual CO2 efflux from both moist and dry tundra ecosystems by 45–55% compared to current ambient temperatures; (2) deeper winter snow cover will increase winter CO2 efflux in both moist and dry tundra ecosystems, but will decrease net summer CO2 efflux; and (3) deeper winter snow cover coupled with warmer summer temperatures will nearly double the annual amount of CO2 emitted from moist tundra and will result in a 24% increase in the annual CO2 efflux of dry tundra. If, as predicted, climate change alters both winter snow deposition and summer temperatures, then shifts in CO2 exchange between the biosphere and atmosphere will likely not be uniform across the Arctic tundra landscape. Increased snow deposition in dry tundra is likely to have a larger effect on annual CO2 flux than warmer summer temperatures alone or warmer temperatures coupled with increased winter snow depth. The combined effects of increased summer temperatures and winter snow deposition on annual CO2 flux in moist tundra will be much larger than the effects of either climate change scenario alone.

Keywords

Arctic Tundra Winter Snow Tundra Ecosystem Heath Tundra Increase Summer Temperature 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Billings, W. D., Luken, J. O., Mortensen, D. A., and Peterson, K. M.: 1982, 'Arctic Tundra: A Source or Sink for Atmospheric Carbon Dioxide in a Changing Environment', Oecologia 53, 7–11.Google Scholar
  2. Brooks, P. D., Williams, M. W., and Schmidt, S. K.: 1996, 'Microbial Activity under Alpine Snowpacks, Niwot Ridge, Colorado', Biogeochemistry 32, 93–113.Google Scholar
  3. Brooks, P. D., Schmidt, S. K., and Williams, M. W.: 1997, 'Winter Production of CO2 and N2O from Alpine Tundra: Environmental Controls and Relationship to Inter-System C and N Fluxes', Oecologia 110, 403–413.Google Scholar
  4. Chapin, F. S. and Shaver, G. R.: 1985, 'Individualistic Growth Responses of Tundra Species to Environmental Manipulations in the Field', Ecology 66, 564–576.Google Scholar
  5. Chapin, F. S., Shaver, G. R., Giblin, A. E., Nadelhoffer, K. J., and Laundre, J. A.: 1995, 'Responses of Arctic Tundra to Experimental and Observed Changes in Climate', Ecology 76, 694–711.Google Scholar
  6. Christensen, T. R., Michelsen, A., Jonasson, S., and Schmidt, I. K.: 1997, 'Carbon Dioxide and Methane Exchange of a Subarctic Heath in Response to Climate Change Related to Environmental Manipulations', Oikos 79, 34–44.Google Scholar
  7. Cline, J. S. and Schimel, J. P.: 1995, 'Microbial Activity of Tundra and Taiga Soils at Sub-Zero Temperatures', Soil Biol. Biochem. 27, 1231–1234.Google Scholar
  8. Cropper W. P., Ewel, K. C., and Raich, J. W.: 1985, 'The Measurement of Soil CO2 Evolution in situ', Pedobiologia, 28, 35–40.Google Scholar
  9. du Plessis, J. P. and Masliyah, J. H.: 1991, 'Flow through Isotropic Granular Porous Media', Transp. Porous Media, 6, 207–221.Google Scholar
  10. Fahnestock, J. T., Jones, M. H., Brooks, P. D., Walker, D. A., and Welker, J. M.: 1998, 'Winter and spring CO2 Efflux from Tundra Communities of Northern Alaska', J. Geophys. Res. 103 (D22), 29023–29027.Google Scholar
  11. Fahnestock, J. T., Jones, M. H., and Welker, J. M.: 1999, 'Wintertime CO2 Efflux from Arctic Soils: Implications for Annual Carbon Budgets', Global Biogeochem. Cycles, in press.Google Scholar
  12. Giblin, A. E., Nadelhoffer, K. J., Shaver, G. R., Laundre, J. A., and McKerrow, A. J.: 1991, 'Biogeochemical Diversity along a Riverside Toposequence in Arctic Alaska', Ecol. Monogr. 61, 415–435.Google Scholar
  13. Grogan, P. and Chapin, F. S. III: 1997, 'Belowground CO2 Flux in Alaska Tundra: Effects of Climate and Vegetation-Type with Regional Extrapolation', Bull. Ecol. Soc. Amer.. 78, 99.Google Scholar
  14. Henry, G. H. R. and Molau, U.: 1997, 'Tundra Plants and Climate Change: The International Tundra Experiment', Global Change Biol. 3, 1–9.Google Scholar
  15. Johnson, L. C., Shaver, G. R., Giblin, A. E., Nadelhoffer, K. J., Rastetter, E. R., Laundre, J. A., and Murray, G. L.: 1996, 'Effects of Drainage and Temperature on Carbon Balance of Tussock Tundra Microcosms', Oecologia 108, 737–748.Google Scholar
  16. Jones, M. H., Fahnestock, J. T., Walker, D. A., Walker, M. D., and Welker, J. M.: 1998, 'Carbondioxide Fluxes in Moist and Dry Arctic Tundra during the Snow Free Season: Responses to Increases in Summer Temperature and Winter Snow Accumulation', Arct. Alp. Res. 30, 373–380.Google Scholar
  17. Jones, M. H., Fahnestock, J. T., and Welker, J. M.: 1999, 'Early and Late Winter CO2 Efflux from Arctic Tundra in the Kuparuk River Watershed, Alaska, U.S.A.', Arct. Alp. Res. 31, 187–190.Google Scholar
  18. Marion, G. M., Henry, G. H. R., Freckman, D., Johnstone, J., Jones, G., Jones, M. H., Levesque, E., Molau, U., Molgaard, P., Parsons, A. N., Svoboda, J., and Virginia, R. A.: 1997a, 'Open-Top Designs forManipulating Field Temperature in High-Latitude Ecosystems', Global Change Biol. 3, 20–32.Google Scholar
  19. Marion, G. M., Bockheim, J. G., and Brown, J.: 1997b, 'Arctic Soils and the ITEX Experiment', Global Change Biol. 3, 33–43.Google Scholar
  20. Maxwell, B.: 1992, 'Arctic Climate: Potential for Change under Global Warming', in: Chapin, F. S., Jeffries, R. L., Reynolds, J. F., Shaver, G. R., and Svoboda, J. (eds), Arctic Ecosystems in a Changing Climate: An Ecophysiological Perspective, Academic Press, San Diego, CA, pp. 11–34.Google Scholar
  21. McKane, R. B., Rastetter, E. B., Shaver, G. R., Nadelhoffer, K. J., Giblin, A. E., Laundre, J. A., and Chapin, F. S. III.: 1997, 'Climatic Effects on Tundra Carbon Storage Inferred from Experimental Data and a Model', Ecology 78, 1188–1198.Google Scholar
  22. Nadelhoffer, K. J., Giblin, A. E., Shaver, G. R., and Laundre, J. A.: 1991, 'Effects of Temperature and Substrate Quality on Element Mineralization in Six Arctic Soils', Ecology 72: 242–253.Google Scholar
  23. Oechel, W. C. and Billings, W. D.: 1992, 'Effects of Global Change on the Carbon Balance of Arctic Plants and Ecosystems', in: Chapin, F. S., Jeffries, R. L., Reynolds, J. F., Shaver, G. R., and Svoboda, J. (eds), Arctic Ecosystems in a Changing Climate: An Ecophysiological Perspective, Academic Press, San Diego, CA, pp. 139–168.Google Scholar
  24. Oechel, W. C. and Vourlitis, G. L.: 1994, 'The Effects of Climate Change on Land-Atmosphere Feedbacks in Arctic Tundra Regions', Trends Ecol. Evol. 9, 324–329.Google Scholar
  25. Oechel, W. C., Hastings, S. J., Vourlitis, G. L., Jenkins, M. A., Riechers, G., and Grulke, N.: 1993, 'Recent Changes of Arctic Tundra Ecosystems from a Carbon Sink to a Source', Nature 361, 520–523.CrossRefGoogle Scholar
  26. Oechel, W. C., Vourlitis, G. L., Hastings, S. J., and Bochkarev, S. A.: 1995, 'Change in Arctic CO2 Flux over Two Decades: Effects of Climate Change at Barrow, Alaska', Ecol. Appl. 5, 846–855.Google Scholar
  27. Oechel, W. C., Vourlitis, G. L., and Hastings, S.: 1997, 'Cold Season CO2 Emission from Arctic Soils', Global Biogeochem. Cycles 11, 163–172.Google Scholar
  28. Osterkamp, T. E. and Romanovsky, V. E.: 1997, 'Freezing of the Active Layer on the Coastal Plain of the Alaskan Arctic', Permafrost Periglacial Processes 8, 23–44.Google Scholar
  29. SAS Institute: 1989, SAS/STAT User's Guide, Version 6, 4th edn., SAS Institute Inc., Cary, NC, p. 943.Google Scholar
  30. Sommerfeld, R. A., Mosier, A. R., and Musselman, R. C.: 1993, 'CO2, CH4 and N2O Flux through a Wyoming Snowpack and Implications for Global Budgets', Nature 361, 140–142.CrossRefGoogle Scholar
  31. Vourlitis, G. L., Oechel, W. C., Hastings, S. J., and Jenkins, M. A.: 1993, 'A System for Measuring in situ CO2 and CH4 Flux in Unmanaged Ecosystems: An Arctic Example', Func. Ecol. 7, 369–379.Google Scholar
  32. Walker, M. D., Walker, D. A., Arft, A. M., Bardsley, T., Brooks, P. D., Fahnestock, J. T., Jones, M. H., Losleben, M., Parsons, A. N., Seastedt, T. R., Turner, P. L., and Welker, J. M.: 1999, 'Long-Term Experimental Manipulation of Winter Snow Regime and Summer Temperature in Arctic and Alpine Tundra: An Integrated Ecosystem Approach', Hydrol. Processes, in press.Google Scholar
  33. Watson, R. T., Ziinyowera, M. C., Moss, R. H., and Dokken, D. J.: 1996, 'Climate Change 1996: Impacts, Adaptations and Mitigation of Climate Change: Scientific-Technical Analyses', Cambridge University Press, p. 878.Google Scholar
  34. Welker, J. M., Molau, U., Parson, A. N., Robinson, C., and Wookey, P. A.: 1997a, 'Responses of Dryas octopetala to ITEX Environmental Manipulations: A Synthesis with Circumpolar Comparisons', Global Change Biol. 3, 61–73.Google Scholar
  35. Welker, J. M., Jones, M. H., Walker, M. D., Walker, D. A., and Fahnestock, J. T.: 1997b, 'Response of Moist and Dry Tundra to Increases in Snow Depth and Warmer Summer Temperatures', Ecol. Soc. Amer. Bull. 78, 329.Google Scholar
  36. Zimov, S. A., Davidov, S. P., Voropaev, Y. V., Prosiannikov, S. F., Semiletov, I. P., Chapin, M. C., and Chapin, F. S.: 1996, 'Siberian CO2 Efflux in Winter as a CO2 Source and Cause of Seasonality in Atmospheric CO2', Clim. Change 33, 111–120.Google Scholar

Copyright information

© Kluwer Academic Publishers 2000

Authors and Affiliations

  • J. M. Welker
    • 1
  • J. T. Fahnestock
    • 1
  • M. H. Jones
    • 2
  1. 1.Department of Renewable ResourcesUniversity of WyomingLaramieU.S.A.
  2. 2.Department of Evolution, Ecology, and Organismal BiologyThe Ohio State UniversityColumbusU.S.A.

Personalised recommendations