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A drought-induced pervasive increase in tree mortality across Canada's boreal forests

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Abstract

Drought-induced tree mortality is expected to increase worldwide under projected future climate changes1,2,3,4. The Canadian boreal forests, which occupy about 30% of the boreal forests worldwide and 77% of Canada's total forested land, play a critical role in the albedo of Earth’s surface5 and in its global carbon budget6. Many of the previously reported regional-scale impacts of drought on tree mortality have affected low- and middle-latitude tropical regions2 and the temperate forests of the western United States3, but no study has examined high-latitude boreal regions with multiple species at a regional scale using long-term forest permanent sampling plots7,8,9. Here, we estimated tree mortality in natural stands throughout Canada's boreal forests using data from the permanent sampling plots and statistical models. We found that tree mortality rates increased by an overall average of 4.7% yr−1 from 1963 to 2008, with higher mortality rate increases in western regions than in eastern regions (about 4.9 and 1.9% yr−1, respectively). The water stress created by regional drought may be the dominant contributor to these widespread increases in tree mortality rates across tree species, sizes, elevations, longitudes and latitudes. Western Canada seems to have been more sensitive to drought than eastern Canada.

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Figure 1: Locations of the 96 forest PSPs in Canada's boreal forests.
Figure 2: Simulated tree mortality dynamics in Canada's boreal forests.

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References

  1. Allen, C. D. et al. A global overview of drought and heat-induced tree mortality reveals emerging climate change risks for forests. Forest Ecol. Manage. 259, 660–684 (2010).

    Article  Google Scholar 

  2. Phillips, O. L. et al. A. Drought sensitivity of the Amazon rainforest. Science 323, 1344–1347 (2009).

    Article  CAS  Google Scholar 

  3. Van Mantgem, P. et al. Widespread increase of tree mortality rates in the western United States. Science 323, 521–524 (2009).

    Article  CAS  Google Scholar 

  4. Carnicer, J. et al. Widespread crown condition decline, food web disruption, and amplified tree mortality with increased climate change-type drought. Proc. Natl Acad. Sci. USA 108, 1474–1478 (2011).

    Article  CAS  Google Scholar 

  5. Bonan, G. B. Forests and climate change: Forcings, feedbacks, and the climate benefits of forests. Science 320, 1444–1449 (2008).

    Article  CAS  Google Scholar 

  6. Kurz, W. A. et al. Risk of natural disturbances makes future contribution of Canada's forests to the global carbon cycle highly uncertain. Proc. Natl Acad. Sci. USA 105, 1551–1555 (2008).

    Article  CAS  Google Scholar 

  7. Piao, S. et al. Net carbon dioxide losses of northern ecosystems in response to autumn warming. Nature 451, 49–53 (2008).

    Article  CAS  Google Scholar 

  8. Hogg, E. H., Brandt, J. P. & Michaelian, M. Impacts of a regional drought on the productivity, dieback, and biomass of western Canadian aspen forests. Can. J. Forest Res. 38, 1373–1384 (2008).

    Article  Google Scholar 

  9. Michaelian, M., Hogg, E. H., Hall, R. J. & Arsenault, E. Massive mortality of aspen following severe drought along the southern edge of the Canadian boreal forest. Glob. Change Biol. 17, 2087–2094 (2011).

    Article  Google Scholar 

  10. Ciais, P. et al. Europe-wide reduction in primary productivity caused by the heat and drought in 2003. Nature 437, 529–533 (2005).

    Article  CAS  Google Scholar 

  11. Zhao, M. & Running, S. W. Drought-induced reduction in global terrestrial net primary production from 2000 through 2009. Science 329, 940–943 (2010).

    Article  CAS  Google Scholar 

  12. Barber, V. A., Juday, G. P. & Finney, B. P. Reduced growth of Alaskan white spruce in the twentieth century from temperature-induced drought stress. Nature 405, 668–673 (2000).

    Article  CAS  Google Scholar 

  13. Arnone, J. A. III et al. Prolonged suppression of ecosystem carbon dioxide uptake after an anomalously warm year. Nature 455, 383–386 (2008).

    Article  CAS  Google Scholar 

  14. Cleland, E. E., Chuine, I., Menzel, A., Mooney, H. A. & Schwartz, M. D. Shifting plant phenology in response to global change. Trends Ecol. Evol. 22, 357–365 (2007).

    Article  Google Scholar 

  15. Parmesan, C. et al. Poleward shifts in geographical ranges of butterfly species associated with regional warming. Nature 399, 579–583 (1999).

    Article  CAS  Google Scholar 

  16. IPCC Climate Change 2007: The Physical Science Basis (eds Solomon, S. et al.) (Cambridge Univ. Press, 2007).

  17. Phillips, O. L. et al. Drought–mortality relationships for tropical forests. New Phytol. 187, 631–646 (2010).

    Article  Google Scholar 

  18. Williams, A. P. et al. Forest responses to increasing aridity and warmth in the southwestern United States. Proc. Natl Acad. Sci. USA 107, 21289–21294 (2010).

    Article  CAS  Google Scholar 

  19. Lenton, T. M. et al. Tipping elements in the Earth’s climate system. Proc. Natl Acad. Sci. USA 105, 1786–1793 (2008).

    Article  CAS  Google Scholar 

  20. Bonsal, B. R. & Wheaton, E. E. Atmospheric circulation comparisons between the 2001 and 2002 and the 1961 and 1988 Canadian prairie droughts. Atmos. Ocean 43, 163–172 (2005).

    Article  Google Scholar 

  21. Girardin, M. P. et al. Trends and periodicities in the Canadian Drought Code and their relationships with atmospheric circulation for the southern Canadian boreal forest. Can. J. Forest Res. 34, 103–119 (2004).

    Article  Google Scholar 

  22. Liu, J., Stewart, R. E. & Szeto, K. K. Moisture transport and other hydrometeorological features associated with the severe 2000/01 drought over the Western and Central Canadian Prairies. J. Clim. 17, 305–319 (2004).

    Article  Google Scholar 

  23. Shabbar, A. & Skinner, W. Summer drought patterns in Canada and the relationship to global sea surface temperatures. J. Clim. 17, 2866–2880 (2004).

    Article  Google Scholar 

  24. Cutforth, H. W. & Judiesch, D. Long-term changes to incoming solar energy on the Canadian Prairie. Agr. Forest Meteorol. 145, 167–175 (2007).

    Article  Google Scholar 

  25. McDowell, N. et al. The interdependence of mechanisms underlying climate-driven vegetation mortality. Trends Ecol. Evol. 26, 523–532 (2011).

    Article  Google Scholar 

  26. Raffa, K. F. et al. Cross-scale drivers of natural disturbances prone to anthropogenic amplification: The dynamics of bark beetle eruptions. Bioscience 58, 501–517 (2008).

    Article  Google Scholar 

  27. Arnone, J. A. III et al. Prolonged suppression of ecosystem carbon dioxide uptake after an anomalously warm year. Nature 455, 383–386 (2008).

    Article  CAS  Google Scholar 

  28. Easterling, D. R., Meehl, G. A., Parmesan, C., Changnon, S. A., Karl, T. R. & Mearns, L. O. Climate extremes: Observations, modeling, and impacts. Science 289, 2068–2074 (2000).

    Article  CAS  Google Scholar 

  29. Kurz, W. A. et al. Mountain pine beetle and forest carbon feedback to climate change. Nature 452, 987–990 (2008).

    Article  CAS  Google Scholar 

  30. Bond-Lamberty, B. et al. Fire as the dominant driver of central Canadian boreal forest carbon balance. Nature 450, 89–92 (2007).

    Article  CAS  Google Scholar 

  31. Stinson, G. et al. An inventory-based analysis of Canada's managed forest carbon dynamics, 1990 to 2008. Glob. Change Biol. 17, 2227–2244 (2011).

    Article  Google Scholar 

Download references

Acknowledgements

Funding for this study was provided by the Natural Sciences and Engineering Research Council of Canada (NSERC) Strategic Network (ForValuenet), an NSERC discovery grant and the China QianRen programme. We thank the Forest Management Branch of Alberta Ministry of Sustainable Resource Development, Saskatchewan Renewable Resources Forestry Branch, the Forestry Branch of Manitoba, Ontario Terrestrial Assessment Program and Ministère des Ressources Naturelles et de la Faune du Québec, and our colleagues (P. Comeau, J. Liu, V. LeMay, S. Huang, J. Parton and K. Zhou) for providing detailed data. C.P. acknowledges the support he received during his sabbatical leave at Northwest A&F University, China. We also thank T. Hogg for his help with our calculations of CMI, P. J. van Mantgem for his assistance with our statistical models, W.Z. for her technical assistance and G. Hart for editorial help, as well as T. Moore, J. Guiot and P. J. van Mantgem for their comments and discussions on the earlier draft of the paper.

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C.P. contributed to the study design, data collection, method development, result analysis and writing of the manuscript. Z.M. and X.L. conducted the data analysis and developed the statistical models. All authors contributed to the data analysis, result discussion and manuscript preparation.

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Correspondence to Changhui Peng.

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The authors declare no competing financial interests.

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Peng, C., Ma, Z., Lei, X. et al. A drought-induced pervasive increase in tree mortality across Canada's boreal forests. Nature Clim Change 1, 467–471 (2011). https://doi.org/10.1038/nclimate1293

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