Landscape genomics of Douglas-fir: understanding its adaptive potential for future climatic conditions

Climate change is currently one of the major concerns within the realms of forest ecology, forest conservation and forest management. The increased frequency, intensity and length of harsher conditions jeopardizes historically well-adapted local populations of long-lived trees by increasing mortality and/or reducing growth, and consequently causing significant losses in ecosystem services. Considering that local populations of conifers might not be able to adapt or migrate at the same pace as climate changes, adaptational lags are expected. Assisted gene flow (AGF) strategies have the potential to mitigate the effects of these adaptational lags by moving adaptive alleles across populations and subsequently, on a broader scale, reducing the negative impact of climate change on species natural ranges.

The reduction of uncertainties associated with the responses of conifers to climate change and the use of AGF are imperative for ensuring healthy forests in the future. We are striving to achieve better: predictions of natural range shifts, understanding of the evolutionary potential of local populations to adapt to future conditions, identification of maladaptation of local populations before and after the introduction of external putatively adaptive alleles, and identification of the major climatic drivers.

Douglas-fir is an ecologically and economically important conifer in its natural range in western North America, and also in other parts of the world where it was introduced for wood supply. Based on projected climatic changes and species climatic niche models, Douglas-fir may have its habitat expanded in some regions while drastically contracted in others. It is unknown which populations may persist or expand under new conditions in the near future, especially if novel climates and other climatic and adaptive genetic uncertainties are taken into account.

Given the incomplete understanding of the adaptation of Douglas-fir to future climates, the general goal is to investigate the evolutionary potential of this species to adapt to extreme cold and drought conditions, and additionally, describe the distribution of phenotypes and genotypes underlying these adaptations throughout the species’ natural range. I will integrate a) phenotypic data from three controlled common garden experiments (87 different seed sources); b) climatic data from each of the seed sources; and c) genomic data from targeted sequence capture (DNA) sequences. This work is part of the CoAdapTree project.

Funding: Genome Canada and Genome BC through the CoAdapTree project

Principal participants: [ Candido Ribeiro | Aitken ]