Additions and deletions of forest area
Why is this indicator important?
Knowing how and why forest areas change over time is important for managing forests sustainably because such changes may result in long-term deletions (e.g., deforestation) from Canada’s forest land base or additions (e.g., afforestation).
- Deforestation means the long-term conversion of forest to other land uses. In Canada, deforestation is mainly the result of forest land being converted to use for agriculture, industrial development, resource extraction and urban expansion. Harvesting, when followed by regeneration, is not deforestation.
- Afforestation means the establishment of new forests on previously unforested land.
Because forests provide a number of ecological services, such as water purification and erosion control, additions and deletions of forest area affect soil and water conservation as well as the overall capacity of forests to recover from natural and human disturbances. Forests also act as sinks and sources of carbon, so monitoring forest additions and deletions help scientists gauge Canada’s ability to meet its climate change related commitments.
What has changed?
Over the last two decades in Canada, the annual rate of deforestation has declined, dropping from just over 64 000 hectares in 1990 to about 45 000 hectares in 2010. Spikes in this downward trend have occurred for short periods, however, when forested areas have been submerged by water reservoirs associated with large hydroelectric projects. For example, 35 000 hectares of forest area were lost in the mid-1990s and another 28 000 hectares were lost in the mid-2000s because of the development of reservoirs.
In 2010, deforestation resulted in net emissions of 15.7 million tonnes of carbon dioxide equivalent, down from 27.5 million tonnes in 1990. (These numbers account for lateral transfers of carbon from the forest ecosystem to the forest product sector, in the form of  greenhouse gas emissions to the atmosphere and  residual emissions from deforestation in previous years.)
Limited afforestation has been carried out in Canada since 1990 relative to the total area of forested land. Although millions of trees are planted each year to supplement natural regeneration, these efforts are occurring primarily as part of sustainable forest management in areas that were already forested. Urban and rural planting initiatives are underway in many regions, including Quebec, Ontario and the Prairie provinces.
aResulting from the creation of permanent forest access roads.
cIncludes mines, gravel pits, oil and gas projects and highway construction.
dIncludes urban development.
eIncludes ski hills and golf courses.
fNumbers may not equal total due to rounding.
Source: Environment Canada 2012