Ecosystems

, Volume 10, Issue 2, pp 280–292 | Cite as

Plant Species Composition and Productivity following Permafrost Thaw and Thermokarst in Alaskan Tundra

  • Edward A. G. Schuur
  • Kathryn G. Crummer
  • Jason G. Vogel
  • Michelle C. Mack
Article

Abstract

Climate warming is expected to have a large impact on plant species composition and productivity in northern latitude ecosystems. Warming can affect vegetation communities directly through temperature effects on plant growth and indirectly through alteration of soil nutrient availability. In addition, warming can cause permafrost to thaw and thermokarst (ground subsidence) to develop, which can alter the structure of the ecosystem by altering hydrological patterns within a site. These multiple direct and indirect effects of permafrost thawing are difficult to simulate in experimental approaches that often manipulate only one or two factors. Here, we used a natural gradient approach with three sites to represent stages in the process of permafrost thawing and thermokarst. We found that vascular plant biomass shifted from graminoid-dominated tundra in the least disturbed site to shrub-dominated tundra at the oldest, most subsided site, whereas the intermediate site was co-dominated by both plant functional groups. Vascular plant productivity patterns followed the changes in biomass, whereas nonvascular moss productivity was especially important in the oldest, most subsided site. The coefficient of variation for soil moisture was higher in the oldest, most subsided site suggesting that in addition to more wet microsites, there were other microsites that were drier. Across all sites, graminoids preferred the cold, dry microsites whereas the moss and shrubs were associated with the warm, moist microsites. Total nitrogen contained in green plant biomass differed across sites, suggesting that there were increases in soil nitrogen availability where permafrost had thawed.

Key words

tundra vegetation biomass net primary productivity permafrost Alaska thermokarst climate change nitrogen soil moisture 

REFERENCES

  1. Arft AM, Walker MD, Gurevitch J, Alatalo JM, Bret-Harte MS, Dale M, Diemer M, Gugerli F, Henry GHR, Jones MH, Hollister RD, Jonsdottir IS, Laine K, Levesque E, Marion GM, Molau U, Molgaard P, Nordenhall U, Raszhivin V, Robinson CH, Starr G, Stenstrom A, Stenstrom M, Totland O, Turner PL, Walker LJ, Webber PJ, Welker JM, Wookey PA. 1999. Responses of tundra plants to experimental warming: meta-analysis of the international tundra experiment. Ecol Monogr 69:491–511Google Scholar
  2. Bartleman AP, Miyanishi K, Burn CR, Cote MM. 2001. Development of vegetation communities in a retrogressive thaw slump near Mayo, Yukon Territory: a 10-year assessment. Arctic 54:149–56Google Scholar
  3. Billings WD. 1987. Carbon balance of Alaskan tundra and taiga ecosystems: past, present, and future. Quat Sci Rev 6:165–77Google Scholar
  4. Bret-Harte MS, Shaver GR, Chapin FS. 2002. Primary and secondary stem growth in arctic shrubs: implications for community response to environmental change. J Ecol 90:251–67CrossRefGoogle Scholar
  5. Camill P. 1999. Peat accumulation and succession following permafrost thaw in the boreal peatlands of Manitoba, Canada. Ecoscience 6:592–602Google Scholar
  6. Camill P. 2000. How much do local factors matter for predicting transient ecosystem dynamics? Suggestions from permafrost formation in boreal peatlands. Global Change Biol 6:169–82CrossRefGoogle Scholar
  7. Camill P, Clark JS. 1998. Climate change disequilibrium of boreal permafrost peatlands caused by local processes. Am Nat 151:207–22CrossRefPubMedGoogle Scholar
  8. Camill P, Lynch JA, Clark JS, Adams JB, Jordan B. 2001. Changes in biomass, aboveground net primary production, and peat accumulation following permafrost thaw in the boreal peatlands of Manitoba, Canada. Ecosystems 4:461–78CrossRefGoogle Scholar
  9. Chapin FS III, Shaver GR. 1996. Physiological and growth responses of arctic plants to a field experiment simulating climatic change. Ecology 77:822–40CrossRefGoogle Scholar
  10. Chapin FS, Sturm M, Serreze MC, McFadden JP, Key JR, Lloyd AH, McGuire AD, Rupp TS, Lynch AH, Schimel JP, Beringer J, Chapman WL, Epstein HE, Euskirchen ES, Hinzman LD, Jia G, Ping CL, Tape KD, Thompson CDC, Walker DA, Welker JM. 2005. Role of land-surface changes in Arctic summer warming. Science 310:657–60PubMedCrossRefGoogle Scholar
  11. Circumpolar Artic Vegetation Map. 2003. Scale 1:7,500,000. Conservation of Artic Flora and Fauna (CAFF) map no 1. US fish and wildlife service, Anchorage, AlaskaGoogle Scholar
  12. Clymo RS. 1970. Growth of Sphagnum—methods of measurement. J Ecol 58:13CrossRefGoogle Scholar
  13. Davis N. 2000. Permafrost: a guide to frozen ground in transition. Fairbanks: University of Alaska PressGoogle Scholar
  14. Dormann CF, Woodin SJ. 2002. Climate change in the Arctic: using plant functional types in a meta-analysis of field experiments. Funct Ecol 16:4–17CrossRefGoogle Scholar
  15. Epstein HE, Beringer J, Gould WA, Lloyd AH, Thompson CD, Chapin FS, Michaelson GJ, Ping CL, Rupp TS, Walker DA. 2004. The nature of spatial transitions in the Arctic. J Biogeogr 31:1917–33CrossRefGoogle Scholar
  16. Hobbie SE, Chapin FS III. 1998. The response of tundra plant biomass, aboveground production, nitrogen, and CO2 flux to experimental warming. Ecology 79:1526–44Google Scholar
  17. Hollister RD, Webber PJ, Tweedie CE. 2005. The response of Alaskan arctic tundra to experimental warming: differences between short- and long-term responses. Global Change Biol 11:525–36CrossRefGoogle Scholar
  18. Houghton JT, Meira Filho LG, Callander BA, Harris N, Kattenberg A, Maskell K, Eds. 1996. Climate change 1995. The science of climate change. Cambridge: Cambridge University PressGoogle Scholar
  19. IPCC. 2001. Climate change 2001: the scientific basis. contributions of working Group I to the third assessment report of the intergovernmental panel on climate change. Cambridge: Cambridge University PressGoogle Scholar
  20. Jonasson S, Michelsen A, Schmidt IK, Nielsen EV. 1999. Responses in microbes and plants to changed temperature, nutrient, and light regimes in the arctic. Ecology 80:1828–43CrossRefGoogle Scholar
  21. Jonsdottir IS, Magnusson B, Gudmundsson J, Elmarsdottir A, Hjartarson H. 2005. Variable sensitivity of plant communities in Iceland to experimental warming. Global Change Biol 11:553–63CrossRefGoogle Scholar
  22. Jorgenson MT, Racine CH, Walters JC, Osterkamp TE. 2001. Permafrost degradation and ecological changes associated with a warming climate in central Alaska. Clim Change 48:551–79CrossRefGoogle Scholar
  23. Jorgenson MT, Shur YL, Pullman ER. 2006. Abrupt increase in permafrost degradation in Arctic Alaska. Geophys Res Lett 33Google Scholar
  24. Lachenbruch AH, Marshall BV. 1986. Climate change: geothermal evidence from permafrost in the Alaskan arctic. Science 34:689–96CrossRefGoogle Scholar
  25. Liston GE, McFadden JP, Sturm M, Pielke RA. 2002. Modelled changes in arctic tundra snow, energy and moisture fluxes due to increased shrubs. Global Change Biol 8:17–32CrossRefGoogle Scholar
  26. Lloyd AH, Yoshikawa K, Fastie CL, Hinzman L, Fraver M. 2003. Effects of permafrost degradation on woody vegetation at arctic treeline on the Seward Peninsula, Alaska. Permafr Periglac Process 14:93–101CrossRefGoogle Scholar
  27. Mack MC, Schuur EAG, Bret-Harte MS, Shaver GR, Chapin FS. 2004. Ecosystem carbon storage in arctic tundra reduced by long-term nutrient fertilization. Nature 431:440–3PubMedCrossRefGoogle Scholar
  28. Marion GM, Henry GHR, Freckman DW, Johnstone J, Jones G, Jones MH, Levesque E, Molau U, Molgaard P, Parsons AN, Svoboda J, Virginia RA. 1997. Open-top designs for manipulating field temperature in high-latitude ecosystems. Global Change Biol 3:20–32CrossRefGoogle Scholar
  29. Oechel WC, Cowles S, Grulke N, Hastings SJ, Lawrence W, Prudhomme T, Riechers G, Strain B, Tissue D, Vourlitis G. 1994. Transient nature of CO2 fertilization in arctic tundra. Nature 371:500–03CrossRefGoogle Scholar
  30. Osterkamp TE, Romanovsky VE. 1999. Evidence for warming and thawing of discontinuous permafrost in Alaska. Permafr Periglac Process 10:17–37CrossRefGoogle Scholar
  31. Reich PB, Walters MB, Ellsworth DS. 1992. Leaf lifespan in relation to leaf, plant and stand characteristics among diverse ecosystems. Ecology 62:365–92Google Scholar
  32. Romanovsky VE, Osterkamp TE. 2000. Effecs of unfrozen water on heat and mass transport processes in the active layer and permafrost. Permafr Periglac Process 11:219–39CrossRefGoogle Scholar
  33. Serreze MC, Walsh JE, Chapin FS III, Osterkamp T, Dyurgerov M, Romanovsky V, Oechel WC, Morison J, Zhang T, Barry RG. 2000. Observational evidence of recent change in the northern high-latitude environment. Clim Change 46:159–207CrossRefGoogle Scholar
  34. Shaver GR, Laundre J. 1997. Exsertion, elongation, and senescence of leaves of Eriophorum vaginatum and Carex bigelowii in Northern Alaska. Global Change Biol 3:146–57CrossRefGoogle Scholar
  35. Shaver GR, Billings WD, Chapin FS III, Giblin AE, Nadelhoffer KJ, Oechel WC, Rastetter EB. 1992. Global change and the carbon balance of arctic ecosystems. BioScience 61:415–35Google Scholar
  36. Shaver GR, Canadell J, Chapin FS, Gurevitch J, Harte J, Henry G, Ineson P, Jonasson S, Melillo J, Pitelka L, Rustad L. 2000. Global warming and terrestrial ecosystems: a conceptual framework for analysis. Bioscience 50:871–82CrossRefGoogle Scholar
  37. Shaver GR, Bret-Harte SM, Jones MH, Johnstone J, Gough L, Laundre J, Chapin FS. 2001. Species composition interacts with fertilizer to control long-term change in tundra productivity. Ecology 82:3163–81Google Scholar
  38. Sturm M, Racine C, Tape K. 2001. Climate change—increasing shrub abundance in the Arctic. Nature 411:546–7PubMedCrossRefGoogle Scholar
  39. Tape K, Sturm M, Racine C. 2006. The evidence for shrub expansion in Northern Alaska and the Pan-Arctic. Global Change Biol 12:686–702CrossRefGoogle Scholar
  40. Turetsky MR, Wieder RK, Williams CJ, Vitt DH. 2000. Organic matter accumulation, peat chemistry, and permafrost melting in peatlands of boreal Alberta. Ecoscience 7:379–92Google Scholar
  41. van Wijk MT, Clemmensen KE, Shaver GR, Williams M, Callaghan TV, Chapin FS, Cornelissen JHC, Gough L, Hobbie SE, Jonasson S, Lee JA, Michelsen A, Press MC, Richardson SJ, Rueth H. 2003. Long-term ecosystem level experiments at Toolik Lake, Alaska, and at Abisko, Northern Sweden: generalizations and differences in ecosystem and plant type responses to global change. Global Change Biol 10:105–23CrossRefGoogle Scholar
  42. Vitt DH, Halsey LA, Zoltai SC. 2000. The changing landscape of Canada’s western boreal forest: the current dynamics of permafrost. Can J Forest Res Rev Can Rech Forest 30:283–7Google Scholar
  43. Walker D. 1996. Community baseline measurements for ITEX studies. In: Molau U, Mølgaard P, Eds. International tundra experiment (ITEX) manual. Copenhagen, Denmark: Danish Polar Center. pp 39–41Google Scholar
  44. Walker MD, Wahren CH, Hollister RD, Henry GHR, Ahlquist LE, Alatalo JM, Bret-Harte MS, Calef MP, Callaghan TV, Carroll AB, Epstein HE, Jonsdottir IS, Klein JA, Magnusson B, Molau U, Oberbauer SF, Rewa SP, Robinson CH, Shaver GR, Suding KN, Thompson CC, Tolvanen A, Totland O, Turner PL, Tweedie CE, Webber PJ, Wookey PA. 2006. Plant community responses to experimental warming across the tundra biome. Proc Natl Acad Sci USA 103:1342–6PubMedCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  • Edward A. G. Schuur
    • 1
  • Kathryn G. Crummer
    • 1
  • Jason G. Vogel
    • 1
  • Michelle C. Mack
    • 1
  1. 1.Department of Botany220 Bartram Hall, University of FloridaGainesvilleUSA

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