Fighting for a forgotten forest
The plight of the tropical forests may be more familiar, but the American public has a much more direct stake in how the forests of the north are managed. The United States consumes 80 percent of Canada's forest products, including pulp, paper, particleboard, and lumber. The boreal zone provides much of the wood, the vast majority of it harvested by clear-cutting, in which loggers mow down every tree in the parcel of forest they're harvesting. U.S. consumers also suck up 60 percent of the oil and gas extracted from northern forests.
Bird-watchers and hunters owe a different debt to the boreal forest. Almost one third of all land birds in the United States and Canada--more than 3 billion birds--head to the region each summer to nest and fledge their young, according to the Boreal Songbird Initiative, a conservation organization. The woods teem with vireos, chickadees, sparrows, shrikes, and flycatchers, drawn by the profusion of insects and the expanses of unbroken forest. Millions of ducks and geese also see this chilly, watery landscape as a little piece of nesting heaven. In fact, 40 percent of North American water birds nest in the boreal forest.
But as the pace of logging and oil and gas drilling has accelerated in some regions, bird populations have declined. In Alberta, only 10 percent of the forest exists in untouched tracts larger than a few square miles, down from about 95 percent in 1960. The rest is shot through with pipelines, roads, and narrow, logged corridors cut by oil and gas companies for seismic testing. Over the past decade, bird populations in many parts of the province have plummeted by 20 to 50 percent, researchers at the University of Alberta say, and habitat fragmentation is probably the major cause.
Going to the mat. The boreal forest's greatest gift, however, may be climatic. When plants photosynthesize, they take in carbon dioxide, the same gas implicated in global warming, and release oxygen. Some of the carbon is sequestered in their limbs, leaves, and roots. Typically, lush landscapes hold the most carbon. But surprisingly, the spare woodland of the far north stores more carbon than any other land ecosystem, and not just because the forests still cover a lot of territory. The secret is the soil, which is made up of a mineral layer, covered by a blanket of partially decomposed plant matter, and topped by masses of living moss and lichen. In northern forests this carbon-rich, layered mat can get several feet thick because cold, wet conditions hamper the growth of microbes that would break down the plant matter. The mat locks up far more carbon than the scrubby trees--up to 90 percent of the forest's total, says University of Maryland fire ecologist Eric Kasischke.
What's the harm, then, in logging, which at first glance would seem to liberate only a fraction of the carbon? Scientists are concerned because after an area is cut and shade-giving trees removed, the ground typically warms up. Warmer conditions foster microbial activity, which could release a flood of carbon dioxide into the atmosphere.
advertisement
