OregonNews Menu

UO researchers improve maps of forests in Alaska and British Columbia

UO researchers improve maps of forests in Alaska and British Columbia

Their new maps, covering hard-to-map areas, suggest the forests store more carbon than thought

Challenges like climate change, conservation planning and natural resource management often extend beyond geographic and political borders, which means it’s vital that analysts and decision-makers can access environmental maps that do the same.

When University of Oregon researchers recognized inconsistencies and deficiencies in the maps of forest ecosystems across coastal Alaska and British Columbia, they created a new series of maps that offer a more complete and comprehensive picture of the region — and one that is more consistent with how the Western United States has been mapped.

The new maps are an essential resource for managing forests, projecting the impacts of climate change and planning conservation initiatives. 

“These forests are incredibly important for their role in storing and cycling carbon, providing ecosystem services, and supporting biodiversity,” said James Lamping, a postdoctoral fellow in the UO’s geography department. “But despite their global and regional significance, there was a distinct shortage of consistent, cross-boundary mapping that could inform critical monitoring efforts and management decisions.”

Different kinds of trees growing in different habitats

A wetland bog, called a muskeg, just south of Juneau. Trees here are less productive, mostly consisting of lodgepole pine. In the background, on the well-drained slopes of the mountains, more productive and dense forests are seen.

A wetland bog, called a muskeg, just south of Juneau. Trees here are less productive, mostly consisting of lodgepole pine. In the background, on the well-drained slopes of the mountains, more productive and dense forests are seen.

Through their mapping, the researchers also found that the coastal forests of Alaska and British Columbia offer greater carbon storage than previous estimates. This was especially true in Southeast Alaska, where their predictions were 30 to 53 percent higher than other studies.

“Our estimates of carbon storage were higher than previous estimates in part because we created detailed maps of areas that were not supported by strong forest inventory data, like hard-to-access terrain, national parks and wilderness areas,” said Lamping, who did the research as a graduate student in the lab of UO research assistant professor Melissa Lucash. “Because these areas tend to harbor old, unmanaged forests that are rich in biomass, our estimates revealed increased amounts of aboveground biomass stored in the trees throughout the region.”

Lucash, Lamping and their colleagues published their work in Forest Ecology and Management this March.

The researchers noted significant inconsistencies between how forests were being mapped across geographic borders and political boundaries. Jurisdictions were getting data from different sources and weren’t using the same methodologies to plot the data.

“The approaches were different enough that you couldn’t just stitch them together and get a continuous, accurate estimation of the landscape,” Lamping said. “Our goal was to improve the estimates for both regions and also create more compatible maps that could be used with similar maps of the Lower 48.”

Melissa Lucash and James Lamping hiking near a glacier

Melissa Lucash and James Lamping hiking near a glacier.

Melissa Lucash and James Lamping hiking near a glacier.

To improve and enhance the maps for the region, the researchers obtained thousands of data points from federal agencies through official agreements. Then they integrated extensive cross-border forest inventory data into their modeling system.

They also synchronized mapping techniques between the United States and Canada to reconcile differences in methodologies. And then they matched their work to the rest of the Western United States, so there’s a consistent map of forests from Southern California to Kodiak Island in Alaska, a distance of almost 4,000 miles.  

They used an innovative strategy for creating estimates of forest structure where strong data wasn’t available, particularly wilderness areas, parks and other inaccessible terrain where it’s more challenging to conduct field surveys. To do that, they compared forest inventory data with satellite images and environmental information so they could formulate estimates for landscape composition.

They assessed different environmental factors, like moisture and heat, alongside vegetation data from neighboring plots and satellite images of the landscape so they could piece together clues about the forest conditions across the entire region being mapped. They also graded the certainty of each estimate so it was clear where more data would be helpful.

One of the greatest challenges of mapping those estimates was working through the many layers involved, Lamping said, especially creating continuous satellite imagery without cloud cover and snow. That might be an easier task in a sunny, desert landscape, but it proved to be quite difficult when mapping rainforests across Alaska and British Columbia.

Three satellite maps showing terrain, forest structure and tree species

The researchers combined many kinds of information to create their new maps, including satellite imagery (left) and data on forest structure (center) and species composition. (right) 

The researchers combined many kinds of information to create their new maps, including satellite imagery (left) and data on forest structure (center) and species composition. (right) 

One of the reasons the researchers felt it was so important to do the work is because reliable baseline data wasn’t available for planning conservation projects or modeling different outlooks for the future, especially for climate change.

“You can’t make solid plans for the future if you don’t have a good understanding of the current conditions,” Lamping said. 

“Alaska especially is incredibly understudied, and there just aren’t as many maps of Alaska as there are for other areas,” Lucash added. “But given how much old growth exists in Alaska and how much carbon is stored in that system, we really wanted to learn more about that landscape so we can highlight what’s happening there and make more informed assessments about its future.”

The researchers were primarily focused on mapping temperate rainforests in North America, which are known for being productive areas that contain a high volume of aboveground biomass. As indicated by their name, they’re also very wet environments with lush ecosystems and large, old-growth conifers.

The maps highlight the distribution of tree species, biomass and forest age across the region so researchers can get a comprehensive snapshot of the makeup of each landscape.

“Mapping the species is really critical, especially at more northerly latitudes, where temperatures are warming at a really fast rate,” Lucash said. “Having this information mapped out will be incredibly helpful as tree ranges shift northward with increasing temperatures.”

The team’s next project will build on this work, with a focus on mapping old growth and mature forests throughout the region and outlining how vulnerable they will be to climate change. They also plan to use the maps as starting conditions for modeling what the forests may look like in the future.