Forest adaptation

Managing forests sustainably during a general trend toward warmer conditions creates new variables, opportunities and risks. In theory, increasing levels of carbon dioxide should increase forest growth and expand forest distribution northward, and this is true of BC and the rest of Canada. However, other variables-such as drought-may limit these effects and some forests may in the near term be more vulnerable to fire, insects and diseases. The rate of change, as well as the number and severity of extreme events, will affect both the magnitude of impacts and our ability to respond successfully.

Actively managing our forests can reduce the impact of forest fires, a significant contributor of greenhouse gases. Depending on the rate of climate change and temperature increase, longer-lived plants such as trees may be less able to survive in their environment. Trees usually adapt to changing climatic pressures through natural selection or gradual movement of seeds to more hospitable regions. However, researchers at the Centre for Forest Conservation Genetics and the BC Forest Service are concerned that the rate of climate change anticipated in the next century may exceed the adaptive capacity of our tree species, and both the government and industry are working to determine how forest management practices should change as a result.

Long-term forest planning that considers climate change can minimize potential mismatches between species and future climatic and disturbance regimes. A strong case can be made for planned adaptation, in which future changes are anticipated and forestry practices (e.g., silviculture, harvesting) are adjusted accordingly.

Although many of the impacts of climate change are decades away, Canada's resource managers are using computer models to explore possible adaptation strategies to reduce the vulnerability of forests. By combining this predictive power with applied knowledge of local geography, tree physiology and forest genetics, foresters will be better equipped to make long-term decisions about how to ensure healthy forests in a changing climate.