In many ways our boreal forests are the lungs of the planet. The Pine Beetle is a very severe problem...
"Canada’s boreal forests continue to provide services in the face of climate change. They scrub toxins from the water and air, and they help maintain river and lake ecosystems. They also store
much of the world’s terrestrial carbon, making boreal regions the second lung of the world"
manitobawildlands.org
And from NG
"If the tropical forests, which contain half the planet's woodlands, are one lung of the Earth, then the boreal forests are the other. Both play a vital role in regulating climate as they—along with the ocean, Earth's largest carbon repository—filter out billions of tons of carbon dioxide and other greenhouse gases during photosynthesis, storing the carbon in trees, roots, and soils. But in many ways the boreal forest is the forest the world forgot. Over the past two decades, as the public focused on the destruction of the tropical forests, few looked north to woodlands nearly as vast. That's because tropical forests have been under a full-scale assault—an area twice the size of Florida is lost every year to farming or other activities—while the boreal forests are still relatively intact. Remote and sparsely inhabited, more than half the boreal in Russia and Canada remains essentially untouched.
Still, as my travels in these countries showed, logging, oil and gas drilling, and flooding from hydropower dams are gnawing away at the boreal. Such development is eradicating older forests, harming birds and wildlife, and eroding the traditional subsistence way of life of people like the Khanty. A damaged and diminished forest is also much less able to withstand the changes brought on by global warming. A related increase in fires could also throw an immense, climate-stabilizing system out of whack, causing the boreal forest to produce more greenhouse gases than it absorbs, which, in turn, would likely accelerate global warming.
The intensifying exploitation of the boreal forest, coupled with fears about the effects of global warming, has rallied conservationists, who are campaigning to set aside extensive wild tracts of the north woods. "In terms of maintaining a vast, healthy forest ecosystem, the boreal offers us our last big chance to do it right," said Stewart Elgie, executive director of the Canadian Boreal Trust, a nonprofit conservation organization.
I came to know the world's largest boreal forest through years of work in Russia, journeying from the taiga's heavily logged southern fringe on the Chinese border to beyond the Arctic Circle. There, following aboriginal reindeer herders, I traveled through the zone where the forest fades away, with gnarled larch trees pushing the limits of existence. Though only 20 to 30 feet (six to nine meters) tall, some are more than 500 years old.
I had also been to the tropical forests of South America, where there is more of everything—more trees, more animals, more insects, more tumult. But I prefer the understated charms of the boreal, with its limitless expanse of lakes and ponds and its gentle gradations of green: the pale hues of the reindeer lichen, the black-green of the spruce, the lighter, almost chartreuse tints of aspen and birch. More than anything, perhaps, I am partial to the light of the north woods—slanting rays that in the warmer months cast long evening shadows and suffuse the landscape with a crystalline glow.
On just such an evening in early June I found myself in Alberta's boreal forest with Richard Thomas, a bird expert and author of a government report on the fragmentation of the province's north woods. We were in Sir Winston Churchill Provincial Park, easing our way down a path in a dusky grove of birch, balsam fir, and white spruce, several nearly three feet (one meter) in diameter and towering 90 feet (27 meters) overhead. In places the forest floor was an orderly tableau of ferns, moss, and piles of shredded pinecones left by squirrels. In other places it was an impassable tangle of blown-down trees, their collapse clearing a hole in the canopy, allowing light to nourish new growth. On a rotting "nurse log," saplings had begun to grow. The air was perfumed with the scent of balsam fir.
"Can you hear that slurry sound, that liquid call note?" asked Thomas, 50, whose brown hair fell to his collar. "That's a Swainson's thrush. They're a bird that likes the gloomy habitat of the forest interior."
Thomas and I walked slowly, the Welsh-born scientist noting the dead, gray trunks pocked by pileated woodpeckers, the sound of beetle larvae chewing on the inside of a tree, and the calls of white-throated sparrows, yellow-rumped warblers, and red-breasted nuthatches. Many of the species we heard, and less often spotted, are the migrants that winter in Central and South America and return to Canada's boreal forest to breed.
"With all these old trees and snags, there's a lot of structure and diversity here," said Thomas. "There are many niches for birds and animals." Although he is a boreal aficionado, Thomas acknowledged that the forest is underappreciated. "With the Rockies you get fantastic scenery, and on the Pacific coast you get spectacular forests. But the boreal forest is more subtle. It takes more effort to appreciate. With the boreal you have to be patient. And because it's subtle, the boreal forest doesn't get the respect it deserves."
That rarefied beauty was on display two days later when we visited a fen where nine varieties of orchids were growing. Leaving a gravel road, we hiked down into a forested wetland where clusters of light gray lichens clung to the dead branches of black spruce. Cold, dark water filtered through the fen, underlain by permafrost—a fact that became evident when I took a walking stick and, plunging it through the moss, hit a frozen layer with a thunk. Scattered throughout the fen were delicate, quarter-size white and yellow orchids supported by waxy green leaves.
"The key to the boreal forest is the interconnections between the forested area and the wetlands," Thomas said. "It's a mosaic."
Water and fire have shaped the north woods. The boreal forest has the largest area of wetlands in the world, with Russia and Canada each containing an estimated one to two million lakes and ponds. Yet an ecosystem with so much moisture is, oddly enough, highly susceptible to fire, for compared with tropical forests the boreal zone receives only moderate amounts of rainfall. Fire, set by lightning or man, is the main regenerator of the forest, and in Canada and Russia today immense blazes often destroy as many trees annually as logging. After the fires comes rebirth—the larch and aspen popping up first, often followed by pine, spruce, and fir.
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