Divide and conquer
"The basic point of ecosystem classification is to divide the landscape up into units that have meaning to people," says Val Loewen, a habitat biologist with Environment Yukon. "Usually we use factors like climate, terrain, soils and vegetation to define the units."
"There are many different ways to do this. There's a national framework in place -- the National Ecological Framework -- that uses a division approach, in which the landscape is chunked up into smaller bits based on these ideas."
At its broadest level, the national framework sets out ecozones, of which there are five in the Yukon. At the next level down, the Yukon is divided into 23 ecoregions. These subsets are an example of ecological classification.
These regions can be subdivided into ecodistricts and then further into ecosections, but as Loewen explains, it begins to be less useful because each unit because each unit becomes a standalone with its own name and characteristics, so it's hard to make comparisons among them.
"At some point you want to take a classification approach, not a division approach," says Loewen. "Division results in groups with unique characteristics. On the other hand, a classification approach groups things together based on common traits."
Landscape characteristics you might want to identify would be zones such as alpine, subalpine and boreal. An ecoregion map showing these zones would have just three colours and you could learn a lot about where all mountains are in the Yukon by looking at such a map. But until now, in the Yukon there has been no standardized framework for mapping these kinds of differences among ecosystems.
Currently, a working group consisting of representatives from agencies and the private sector are working together to come up with a standard framework for the territory. Loewen explains that they've decided to use the national framework to the ecodistrict level, and are working collaboratively to develop a classification approach beyond that.
"There's a lot of questions about how to do this," says Loewen.
Part of the challenge lies in the fact that different agencies, researchers and institutions find value in different data, and apply their data in unique ways. What they are setting out to do is like creating a common 'language' with respect to ecosystem classification, so that the knowledge can be developed and built on collectively.
Until now, it's largely been done in an ad hoc way. Loewen explains that with minimal additional effort, people who are collecting ecosystem data can help create information that is of significant value to other resource managers.
"Forestry people might be most interested in trees -- their density, height or species -- and many of us are also quite interested in this," says Loewen. "But we might also want to know where the forest type occurs -- or we might want to know if the forest type has a lot of shrubs or just moss on the grounds."
A standardized framework won't create a lot more work for people, says Loewen. Instead, it creates efficiencies and presents possibilities of recording important information that may be quite valuable to others.
"It's so important to integrate information," she says. A framework will help make this happen.
Loewen lists off a number of ways that the framework will be applied. "There's already a lot of national reporting at an ecoregion level, such as the State of the Environment report, and this will continue."
"In environmental assessment, when you're looking at environmental impacts it's important to know the context, such as how much of a particular type of ecosystem is in an area," she explains. "It is easier to assess the significance of an impact if you know how much of a particular type of ecosystem is being affected by a project."
Ecosystem classification will also be a very useful tool for Yukon's land use planning processes. As Loewen points out, it becomes very difficult to plan for the future of different parts of the landscape if you don't know what's there.
Loewen and her colleagues hope to have the framework completed by March.
- For more information, contact Val Loewen at (867) 667-5281.
