John Bradley ST.CLAIR, Glenn Thomas HOWE

Strategies for conserving forest genetic resources in the face of climate change

Conservation of genetic diversity is important for continued evolution of populations to new environments, as well as continued availability of traits of interest in genetic improvement programs. Rapidly changing climates present new threats to the conservation of forest genetic resources. We can no longer assume that in situ reserves will continue to preserve existing genetic diversity. Management of reserves should become more active. In some reserves, existing genetic diversity should be preserved by creating stands that are more resistant to threats using silvicultural treatments such as thinning and prescribed burning. In other reserves, natural selection and adaptation to changed environments should be promoted by increasing within population genetic diversity and promoting gene flow. This may be done by locating reserves in areas of high environmental heterogeneity, minimizing fragmentation, and using assisted colonization to increase genetic diversity by establishing populations adapted to future climates within or adjacent to reserves. Threats to native stands from climate change and other interacting threats should bring a renewed importance to ex situ collections, particularly for rare and disjunct populations and those at the warmer and drier edges of a species range. Assisted colonization to move threatened populations to new environments must be considered as an additional conservation measure.

Anahtar Kelimeler:

Key words: Climate change, genetic conservation, adaptation

Strategies for conserving forest genetic resources in the face of climate change

Keywords:

Key words: Climate change, genetic conservation, adaptation,

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Aitken SN, Yeaman S, Holliday JA, Wang T & Curtis-McLane S (2008). Adaptation, migration or extirpation: climate change outcomes for tree populations. Evol Appl 1: 95-111.
Campbell RK (1979). Genecology of Douglas-fi r in a watershed in the Oregon Cascades. Ecology 60: 1036-1050.
Carroll AL, Regneire J, Logan JA, Taylor SW, Bentz B & Powell JA (2006). Impacts of climate change on range expansion by the mountain pine beetle. Mountain Pine Beetle Initiative Working Paper 2006-14. Ontario, Canada: Canadian Forest Service.
Case TJ & Taper ML (2000). Interspecifi c competition, environmental gradients, gene fl ow, and the coevolution of species’ borders. Am Nat 155: 583-605.
Davis MB & Shaw RG (2001). Range shift s and adaptive responses to Quaternary climate change. Science 292: 673-679.
Davis MB, Shaw RG & Etterson JR (2005). Evolutionary responses to changing climate. Ecology 86: 1704-1714.
FAO (2006). Global Forest Resources Assessment 2005: Progress towards sustainable management. FAO Forestry Paper 1147. Rome, Italy: Food and Agriculture Organization of the United Nations.
Garcia-Ramos G & Kirkpatrick K (1997). Genetic models of adaptation and gene fl ow in peripheral populations. Evolution 51: 21-28.
Hampe A & Petit RJ (2005). Conserving biodiversity under climate change: the rear edge matters. Ecol Lett 8: 461-467.
Heywood VH (2008). Challenges of in situ conservation of crop wild relatives. Turk J Bot 32: 421-432.
Intergovernmental Panel on Climate Change (2007). Climate change 2007: the physical basis. Summary for Policymakers. Contribution of Working Group 1 to the Fourth Assessment Report on the Intergovernmental Panel on Climate Change. Geneva, Switzerland: IPCC Secretariat, World Meteorological Organization.
Ledig FT (1988). Th e conservation of diversity in forest trees: why and how should genes be conserved? Bioscience 38: 471-479.
Ledig FT, Vargas-Hernández JJ & Johnsen KH (1998). Th e conservation of forest genetic resources: case histories from Canada, Mexico, and the United States. J Forest 96: 32-41.
Ledig FT, Mápula-Larreta M, Bermejo-Velázquez B, Reyes-Hernández V, Florez-López C & Capó-Arteaga MA (2000). Locations of endangered spruce populations in México and the demography of Picea chihuahuana. Madroño 47: 71-88.
Lenoir J, Gégout JC, Marquet PA, de Ruff ray P & Brisse H (2008). A signifi cant upward shift in plant species optimum elevation during the 20th century. Science 320: 1768-1771.
Lipow SR, St.Clair JB & Johnson GR (2002). Ex situ gene conservation for conifers in the Pacifi c Northwest. General Technical Report PNW-GTR-528. Portland, Oregon: US Dept of Agriculture, Pacifi c Northwest Research Station.
Lipow SR, Johnson GR, St.Clair JB & Jayawickrama KJ (2003). Th e role of tree improvement programs for ex situ gene conservation of coastal Douglas-fi r in the Pacifi c Northwest. Forest Genetics 10: 111-120.
McLachlan JS, Hellmann JJ & Schwartz MW (2007). A framework for debate of assisted migration in an era of climate change. Conserv Biol 21: 297-302.
Millar CI & Libby WJ (1991). Strategies for conserving clinal, ecotypic and disjunct population diversity in widespread species. In: Falk DA & Holsinger KE (eds.) Genetics and Conservation of Rare Plants, New York: Oxford University Press, pp. 149-170.
Rehfeldt GE, Ying CC & Wykoff WR (2001). Physiologic plasticity, evolution, and impacts of a changing climate on Pinus contorta. Climatic Change 50: 355-376.
Rehfeldt GE, Tchebakova NM, Parfenova YI, Wykoff WR, Kuzmina NA & Milyutin LI (2002). Intraspecifi c responses to climate in Pinus sylvestris. Global Change Biol 8: 912-929.
Savolainen O, Bokma F, Garcia-Gil R, Komulainen P & Repo T (2004). Genetic variation in cessation of growth and frost hardiness and consequences for adaptation of Pinus sylvestris to climatic changes. Forest Ecol Manag 197: 79-89.
Savolainen O, Pyhäjärvi T & Knürr T (2007). Gene fl ow and local adaptation in trees. Annu Rev Ecol Syst 38: 595-619.
St.Clair JB, Mandel NL & Vance-Borland KW (2005). Genecology of Douglas-fi r in western Oregon and Washington. Ann Bot- London 96: 1199-1214.
St.Clair JB & Howe GT (2007). Genetic maladaptation of coastal Douglas-fi r seedlings to future climates. Global Change Biol 13: 1441-1454.
Wang T, Hamann A, Yanchuk A, O’Neill GA & Aitken SN (2006). Use of response functions in selecting lodgepole pine populations for future climates. Global Change Biol 12: 2404-2416.
Westerling AL, Hidalgo HG, Cayan DR & Swetnam TW (2006). Warming and earlier spring increase western U.S. forest wildfi re activity. Science 313: 940-943.
Woods A, Coates KD, & Hamann A (2005). Is an unprecedented Dothistroma needle blight epidemic related to climate change? BioScience 55: 761-769.