Direct observation of permafrost degradation and rapid soil carbon loss in tundra


Evidence suggests that 5–15% of the vast pool of soil carbon stored in northern permafrost ecosystems could be emitted as greenhouse gases by 2100 under the current path of global warming. However, direct measurements of changes in soil carbon remain scarce, largely because ground subsidence that occurs as the permafrost soils begin to thaw confounds the traditional quantification of carbon pools based on fixed depths or soil horizons. This issue is overcome when carbon is quantified in relation to a fixed ash content, which uses the relatively stable mineral component of soil as a metric for pool comparisons through time. We applied this approach to directly measure soil carbon pool changes over five years in experimentally warmed and ambient tundra ecosystems at a site in Alaska where permafrost is degrading due to climate change. We show a loss of soil carbon of 5.4% per year (95% confidence interval: 1.0, 9.5) across the site. Our results point to lateral hydrological export as a potential pathway for these surprisingly large losses. This research highlights the potential to make repeat soil carbon pool measurements at sentinel sites across the permafrost region, as this feedback to climate change may be occurring faster than previously thought.

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Fig. 1: Annual maximum thaw depth (active layer) of permafrost soils in response to ambient (control) and experimental warming.
Fig. 2: Pools of ambient (control) and warmed permafrost soils.
Fig. 3: Changes in 13C NMR spectra of ambient (control (left)) and experimentally warmed (right) permafrost soils after five years of treatment.

Data availability

All the data and metadata associated with this manuscript are deposited in the Long Term Ecological Research (LTER) Network Information System Data Portal at (, and


  1. 1.

    Schuur, E. A. G. et al. Climate change and the permafrost carbon feedback. Nature 520, 171–179 (2015).

    Article  Google Scholar 

  2. 2.

    Hugelius, G. et al. Estimated stocks of circumpolar permafrost carbon with quantified uncertainty ranges and identified data gaps. Biogeosciences 11, 6573–6593 (2014).

    Article  Google Scholar 

  3. 3.

    Ping, C. L., Jastrow, J. D., Jorgenson, M. T., Michaelson, G. J. & Shur, Y. L. Permafrost soils and carbon cycling. Soil 1, 147–171 (2015).

    Article  Google Scholar 

  4. 4.

    Schaefer, K., Lantuit, H., Romanovsky, V. E., Schuur, E. A. G. & Witt, R. The impact of the permafrost carbon feedback on global climate. Environ. Res. Lett. 9, 085003 (2014).

    Article  Google Scholar 

  5. 5.

    Elberling, B. et al. Long-term CO2 production following permafrost thaw. Nat. Clim. Change 3, 890–894 (2013).

    Article  Google Scholar 

  6. 6.

    Sistla, S. A. et al. Long-term warming restructures Arctic tundra without changing net soil carbon storage. Nature 497, 615–618 (2013).

    Article  Google Scholar 

  7. 7.

    Mack, M. C., Schuur, E. A. G., Bret-Harte, M. S., Shaver, G. R. & Chapin, F. S. III Ecosystem carbon storage in Arctic tundra reduced by long-term nutrient fertilization. Nature 431, 440–443 (2003).

    Article  Google Scholar 

  8. 8.

    Strauss, J. et al. The deep permafrost carbon pool of the Yedoma region in Siberia and Alaska. Geophys. Res. Lett. 40, 6165–6170 (2013).

    Article  Google Scholar 

  9. 9.

    Jorgenson, M. T. & Osterkamp, T. E. Response of boreal ecosystems to varying modes of permafrost degradation. Can. J. For. Res. 35, 2100–2111 (2005).

    Article  Google Scholar 

  10. 10.

    Grønlund, A., Hauge, A., Hovde, A. & Rasse, D. P. Carbon loss estimates from cultivated peat soils in Norway: a comparison of three methods. Nutr. Cycl. Agroecosys. 81, 157–167 (2008).

    Article  Google Scholar 

  11. 11.

    Rogiers, N., Conen, F., Furger, M., Stöckli, R. & Eugster, W. Impact of past and present land-management on the C-balance of a grassland in the Swiss Alps. Glob. Change Biol. 14, 2613–2625 (2008).

    Google Scholar 

  12. 12.

    Natali, S. M., Schuur, E. A. G., Webb, E. E., Hicks Pries, C. E. & Crummer, K. G. Permafrost degradation stimulates carbon loss from experimentally warmed tundra. Ecology 95, 602–608 (2014).

    Article  Google Scholar 

  13. 13.

    Schuur, E. A. G. et al. The effect of permafrost thaw on old carbon release and net carbon exchange from tundra. Nature 459, 556–559 (2009).

    Article  Google Scholar 

  14. 14.

    Romanovsky, W. E. et al. Permafrost. Arctic Report Card (2012).

  15. 15.

    Osterkamp, T. E. Characteristics of the recent warming of permafrost in Alaska. J. Geophys. Res. 112, F02S02 (2007).

    Article  Google Scholar 

  16. 16.

    Jones, M. C. et al. Rapid carbon loss and slow recovery following permafrost thaw in boreal peatlands. Glob. Change Biol. 23, 1109–1127 (2017).

    Article  Google Scholar 

  17. 17.

    Shaver, G. R. et al. Global warming and terrestrial ecosystems: a conceptual framework for analysis. Bioscience 50, 871–882 (2000).

    Article  Google Scholar 

  18. 18.

    Salmon, V. G. et al. Nitrogen availability increases in a tundra ecosystem during five years of experimental permafrost thaw. Glob. Change Biol. 22, 1927–1941 (2016).

    Article  Google Scholar 

  19. 19.

    Schmidt, M. W. I. et al. Persistence of soil organic matter as an ecosystem property. Nature 478, 49–56 (2011).

    Article  Google Scholar 

  20. 20.

    Lehmann, J. & Kleber, M. The contentious nature of soil organic matter. Nature 528, 60–68 (2015).

    Article  Google Scholar 

  21. 21.

    Baldock, J. A. & Skjemstad, J. O. Role of the soil matrix and minerals in protecting natural organic materials against biological attack. Org. Geochem. 31, 697–710 (2000).

    Article  Google Scholar 

  22. 22.

    Davidson, E. A. & Janssens, I. A. Temperature sensitivity of soil carbon decomposition and feedbacks to climate change. Nature 440, 165–173 (2006).

    Article  Google Scholar 

  23. 23.

    Webb, E. E. et al. Increased wintertime CO2 loss as a result of sustained tundra warming. J. Geophys. Res. Biogeosci. 121, 249–265 (2016).

    Article  Google Scholar 

  24. 24.

    Schädel, C. et al. Potential carbon emissions dominated by carbon dioxide from thawed permafrost soils. Nat. Clim. Change 6, 950–953 (2016).

    Article  Google Scholar 

  25. 25.

    Olefeldt, D., Turetsky, M. R., Crill, P. M. & McGuire, A. D. Environmental and physical controls on northern terrestrial methane emissions across permafrost zones. Glob. Change Biol. 19, 589–603 (2013).

    Article  Google Scholar 

  26. 26.

    Vonk, J. E. & Gustafsson, O. Permafrost–carbon complexities. Nat. Geosci. 2, 598–600 (2013).

    Google Scholar 

  27. 27.

    Zhu, Z. & McGuire, A. D. Baseline and Projected Future Carbon Storage and Greenhouse-Gas Fluxes in Ecosystems of Alaska Professional Paper 1826 (USGS, 2016).

  28. 28.

    Abbott, B. W. & Jones, J. B. Permafrost collapse alters soil carbon stocks, respiration, CH4, and N2O in upland tundra. Glob. Change Biol. 21, 4570–4587 (2015).

    Article  Google Scholar 

  29. 29.

    Zhang, X. et al. Importance of lateral flux and its percolation depth on organic carbon export in Arctic tundra soil: implications from a soil leaching experiment. J. Geophys. Res. 122, 796–810 (2017).

    Article  Google Scholar 

  30. 30.

    Tarnocai, C. et al. Soil organic carbon pools in the northern circumpolar permafrost region. Glob. Biogeochem. Cycl. 23, GB2023 (2009).

    Article  Google Scholar 

  31. 31.

    McGuire, A. D. et al. An assessment of the carbon balance of Arctic tundra: comparisons among observations, process models, and atmospheric inversions. Biogeosciences 9, 3185–3204 (2012).

    Article  Google Scholar 

  32. 32.

    Soil Survey Staff Keys to Soil Taxonomy (USDA–NRCS, 2014).

  33. 33.

    Natali, S. et al. Effects of experimental warming of air, soil and permafrost on carbon balance in Alaskan tundra. Glob. Change Biol. 17, 1394–1407 (2011).

    Article  Google Scholar 

  34. 34.

    Natali, S., Schuur, E. & Rubin, R. Increased plant productivity in Alaskan tundra as a result of experimental warming of soil and permafrost. J. Ecol. 100, 488–498 (2012).

    Article  Google Scholar 

  35. 35.

    Mauritz, M. et al. Nonlinear CO2 flux response to 7 years of experimentally induced permafrost thaw. Glob. Change Biol. 23, 3646–3666 (2017).

    Article  Google Scholar 

  36. 36.

    Crowther, T. W. et al. Quantifying global soil carbon losses in response to warming. Nature 540, 104–108 (2016).

    Article  Google Scholar 

  37. 37.

    Hicks Pries, C. E., Schuur, E. A. G. & Crummer, K. G. Holocene carbon stocks and carbon accumulation rates altered in soils undergoing permafrost thaw. Ecosystems 15, 162–173 (2012).

    Article  Google Scholar 

  38. 38.

    Schumacher, B. A. Methods for the Determination of Total Organic Carbon (TOC) in Soils and Sediments EPA/600/R-02/069 (US EPA, 2002).

  39. 39.

    Ellert, B. H., Janzen, H. H., VandenBygaart, A. G. & Bremer, E., in Soil Sampling and Methods of Analysis (eds Carter, M. R. & Gregorich, E. G.) 25–38 (CRC Press, 2007).

  40. 40.

    Lee, J., Hopmans, J. W., Rolston, D. E., Baer, S. G. & Six, J. Determining soil carbon stock changes: simple bulk density corrections fail. Agric. Ecosyst. Environ. 134, 251–256 (2009).

    Article  Google Scholar 

  41. 41.

    McBratney, A. B. & Minasny, B. Comment on “Determining soil carbon stock changes: simple bulk density corrections fail”. Agric. Ecosyst. Environ. 136, 185–186 (2010).

    Article  Google Scholar 

  42. 42.

    IUSS Working Group WRB World Reference Base for Soil Resources 2014 (FAO, 2014).

  43. 43.

    Kaiser, C. et al. Conservation of soil organic matter through cryoturbation in Arctic soils in Siberia. J. Geophys. Res. 112, G02017 (2007).

    Article  Google Scholar 

  44. 44.

    Baldock, J. A. & Smernik, R. J. Chemical composition and bioavailability of thermally altered Pinus resinosa (Red pine) wood. Org. Geochem. 33, 1093–1109 (2002).

    Article  Google Scholar 

  45. 45.

    Simpson, A. J. & Simpson, M. J. in Biophysico-Chemical Processes Involving Natural Nonliving Organic Matter in Environmental Systems (eds Senesi, N., Xing, B. & Huang, P. M.) 589–651 (John Wiley & Sons, 2009).

  46. 46.

    Zuur, A. F., Ieno, E. N., Walker, N. J., Saveliev, A. A. & Smith, G. M. Mixed Effects Models and Extensions in Ecology with R (Springer, 2009).

  47. 47.

    Burnham, K. P. & Anderson, D. R. Model Selection and Multimodel Inference: A Practical Information-Theoretic Approach (Springer, 2002).

  48. 48.

    Ku, H. H. Notes on the use of propagation of error formulas. J. Res. Natl Bur. Stand. C 70C, 263–273 (1966).

    Google Scholar 

  49. 49.

    R Core Team. R: A language and environment for statistical computing (2015).

  50. 50.

    Bates, D., Mächler, M., Bolker, B. & Walker, S. Fitting linear mixed-effects models using lme4. J. Stat. Softw. 67, 1–48 (2015).

    Article  Google Scholar 

  51. 51.

    Kuznetsova, A., Brockhoff, P. B. & Christensen, R. H. B. lmerTest: Tests in Linear Mixed Effects Models (2016).

  52. 52.

    Barton, K. MuMIn: Multi-Model inference (2016).

  53. 53.

    Wickham, H. ggplot2: Elegant Graphics for Data Analysis (Springer, 2009).

  54. 54.

    Wilke, C. O. cowplot: Streamlined Plot Theme and Plot Annotations for ‘ggplot2’ (2016).

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This work was based in part on support provided by the following programs: US Department of Energy, Office of Biological and Environmental Research, Terrestrial Ecosystem Science (TES) Program, Award nos DE-SC0006982 and DE-SC0014085; National Science Foundation CAREER program, Award no. 0747195; National Parks Inventory and Monitoring Program; National Science Foundation Bonanza Creek LTER program, Award no. 1026415 and National Science Foundation Office of Polar Programs, Award no. 1203777. In addition, this project received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska Curie grant agreement 654132. We thank L. Barrios (CSIC) and the NAU statistical consulting lab for assistance with the data analysis.

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E.A.G.S. conceived and designed the study. E.A.G.S. and S.M.N. implemented the field experiment. R.B., G.C., K.G.C., J.A.H., M.M., S.M.N., C.P., C.E.H.P., E.P., C.S., E.A.G.S., V.G.S. and E.E.W. performed the field research and/or data analysis. K.G.C., J.A.H., C.P., E.P., M.M., S.M.N. and V.G.S. conducted the laboratory research. C.P., G.C. and M.M. carried out data analyses. C.P., E.A.G.S. and E.P. wrote the article. All authors substantially discussed the results and contributed to editing the manuscript.

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Correspondence to Edward A. G. Schuur.

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Supplementary descriptions, Supplementary Figs. 1–9 and Supplementary Tables 1–5

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Plaza, C., Pegoraro, E., Bracho, R. et al. Direct observation of permafrost degradation and rapid soil carbon loss in tundra. Nat. Geosci. 12, 627–631 (2019).

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