Canada and Russia have lost an alarming number of trees in recent years, compromising the ecologically rich and carbon-sequestering boreal forests that are native to the regions, according to a new report.
The report, published Thursday by the World Resources Institute (WRI), found that the world’s boreal region has shown the steepest decline in forest cover between 2011 and 2013, with Russia — the country home to the world’s largest area of tree cover — losing an average of 16,600 square miles of tree cover every year. That’s an area, the report points out, that’s larger than Switzerland.
Boreal forests serve as major carbon sinks, so losing the forests is bad news for climate change — though, as the report notes, the light-reflecting land that’s left after forests are removed complicates the climate impact a bit.
Most of the tree loss in Canada and Russia can be attributed to forest fires, which the report notes are expected to occur more frequently and become more intense as the climate warms. Nigel Sizer, global director of WRI’s Forests Program, told ThinkProgress that the report didn’t analyze what percentage of the fires that caused the deforestation could be linked to human activity and what percentage couldn’t, but he did say that an increase in fires, including in the northern latitudes, was in line with climate modelling.
He also said that hotter, more intense fires could have an impact on the forests ecologically. Though forests are adapted to deal with — and even thrive after — occasional wildfires, hotter fires could affect the regeneration of trees and could lead to changes in species abundance.
“Much hotter fire is going to kill a lot more of the trees and is going to kill more of the seed stock in the soil as well,” Sizer said. “If you shift the intensity, you end up with different type of forest eventually.”
Some wildfires can be attributed to natural resource development in both Canada and Russia; Because there’s an increased human presence in these areas, Sizer said, the risk of fire also increases. The report also cited logging and insect pests as drivers of the loss of forest cover.
What the report didn’t analyze, however, was the impact of Canadian tar sands development on the region’s forests. But Global Forest Watch data from last year show that more than 20 percent of Canada’s boreal forest region is “now covered by industrial concessions for timber operations, hydrocarbon development, hydroelectric power reservoirs, and mineral extraction.” Vast swaths of Canada’s boreal forests have been cut down for tar sands mining operations, and according to the Sierra Club, none of this land has been “certified as reclaimed” by Alberta, Canada’s government.
The report, which used satellite maps from Google and the University of Maryland, found that globally, the earth’s tree cover loss was slightly lower in 2013 than it was in 2012, but was still 5.2 percent higher than the 2000–2012 average. In total, the earth lost 69,500 square miles of forests in 2013, a chunk about twice the size of Portugal.
But while global forest cover is decreasing, the report found that things might be looking up for forests in Indonesia, a country that’s historically had high rates of deforestation. Those rates have been so high that 85 percent its emissions come from forest degradation and destruction.
According to the report, in 2013, Indonesia’s yearly loss of tree cover fell to its lowest point in nearly 10 years, and its loss of primary forests — a term that applies to forests that haven’t been cleared in at least 30 years — also slowed. It notes, however, that one year isn’t enough to make a trend, and that a separate 2014 report found that Indonesia’s loss of primary forests increased from 2001–2012.
Still, Sizer called the data on Indonesia “encouraging” and said that, once WRI has figures for 2014 deforestation loss, its researchers will be able to determine whether Indonesia has begun a trend of slowing deforestation.
The WRI report comes on the heels of a study published Monday in Nature Climate Change, which found that despite worldwide deforestation, the globe’s total vegetation has increased since 2003. That’s thanks largely to efforts to plant more trees in China and former Soviet states, and increased plant life in the savanna due to higher levels of rainfall. Sizer said that this study makes sense, even in the context of WRI’s newest report.
“What we’re particularly concerned about is forest loss, so as forests are degraded and cleared, we’re losing biodiversity, losing water services, greenhouse gases are being emitted … and so on,” he said. “This analysis is saying that while were losing forests, at the same time there’s an overall net re-greening taking place … those two things can perfectly well happen at the same time.”
The challenge for scientists, Sizer said, is to determine what a world that’s both greening and losing forest means for climate change.