24th Congress for Conservation Biology, Canada 2010
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Impacts of climate change on plant phenology in temperate and boreal forests of North America
![Figure 1: Long-term trend (1901–1997) in first-flowering dates of Aspen in Alberta (adapted from Beaubien and Freeland (2000). Divergence of Community Bloom Patterns In a controlled warming experiment, Sherry et al. (2007) report that early-flowering grass and herb species flowered earlier, while late-summer flowering species flowered later than in the control (Figure 2). Simulated warming therefore significantly affected the temporal overlap of reproductive stages between successively blooming species. Figure 1: Divergence in flowering date of 12 herbaceous and graminoid species (Sherry et al, 2007). ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],Factors Influencing Plant Phenology The timing of phenophases is thought to be under strong genetic control, leading to regionally adapted ecotypes that are influenced by: Temperature: Leaf unfolding and budburst respond strongly to temperature. Frost : If late season frosts occur after budburst or flowering, reproductive failure and reduced growth of the tree in that season can occur (ref). Chilling: Full winter dormancy may require periods of chilling that includes super-cooling and dessication of cell protoplasm. Photoperiod: Photoperiod initiates dormancy adaptation in latitudinally adapted tree ecotypes. Evapotranspiration: increased surface temperature and likely reduced summer precipitation Drought: Seasonal drought during the growing season which lead to reduce the growth of the tree. ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],Selected References Abu-Asab, M., Peterson, S., Stanwyn, P.M., Shelter, G. and Sylvia, S., (2001) Earlier plant flowering in spring as a response to global warming in the Washington, DC, area Biodiversity Conservation, 10, 597–612. Beaubien EG, Freeland HJ (2000) Spring phenology trends in Alberta, Canada: links to ocean temperature. International Journal of Biometeorology, 44, 53–59. Chuine I, Beaubien E (2001) Phenology is a major determinant of temperate tree range. Ecology Letters, 4, 500–510. Cleland E.E., Chuine I. et al. (2007). Shifting plant phenology in response to global change, TRENDS in Ecology and Evolution, 22 (7) 357-365 IPCC (2007) Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, UK and New York, NY, USA. Lieth, H. (1974) Purposes of a Phenology Book. In: Lieth, H. (ed) Phenology and Seasonality Modeling, Ecological Studies 8. Springer, New York, 444 pp. Morin X., Lechowicz M.J., Augspurger C., O’Keefe J. Viner D., Chuine I. (2009). Leaf phenology in 22 North America tree species during the 21st century. Global Change Biology, 15 961-975. Sherry, B.A. Zhou, H., et al. (2007). Divergence of reproductive phenology under climate warming. PNAS January 2, 2007 vol. 104 no. 1, 198–202 Impacts of climate change on plant phenology in temperate and boreal forests of N. America Amalesh Dhar* 1 , Andrew Park 2 ,Susanne Kames 2 1 Mixedwood Ecology and Management Program, University of Northern British Columbia, 3333 University Way, Prince George, BC, Canada V2N 4Z9 2 Center for Forest Interdisciplinary Research, Department of Biology, University of Winnipeg, 515 Portage Ave. Winnipeg, MB, R3B 2E9 (* Corresponding author : dhar@unbc.ca ) ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],Phenophases and Climate Change. Many of the effects of a warmer climate are likely to be felt primarily through altered timing of phenology or a mismatch between climatic signals and phenology, which could result in failure to complete a given phenophase. Temperature sensitivity of budburst and flowering has resulted in these phenological events being among the first documented fingerprints of climate change (Menzel et al., 2006). Improved phenological predictions are needed to better estimates of future ecosystem productivity, project changes in dominance in multi-species forest stands, and to provide foresters with criteria that can be used to select tree provenances with the best chances of adapting to the future climate. Location Species Time period Change in first flowering Reference North America American elm 1956-1997 ~ - 8 days Chuine et al. (2000) Canada Aspen 1901–1997 - 26 days Beaubien & Freeland (2000) Canada Trembling aspen, chokecherry, serviceberry 1936–2000 - 8 days Beaubien & Freeland (2000) United States 89 Species 1970-1999 - 4.5 days Abu-asab et al.(2001) US northeast American beech, sugar maple, yellow birch 1957–2004 -5 to10 days Richardson et al (2006) United States 11 Species 1970-1999 +3 to 10 days Abu-asab et al.(2001)](https://image.slidesharecdn.com/p2-90dharparketal-100714002656-phpapp02/85/24th-Congress-for-Conservation-Biology-Canada-2010-1-320.jpg)
Impacts of climate change on plant phenology in temperate and boreal forests of North America
