In one of the largest forest conservation agreements ever negotiated, a logging moratorium was announced Tuesday that will suspend timber harvests on more than 111,000 square miles of Canadas northern forests.

The agreement covers nearly 278,000 square miles of woodlands stretching across the continent from northern British Columbia all the way east to Newfoundland. The pact largely ends the conservation wars over wildlife and climate change that have plagued the Canadian lumber industry. It guarantees survival ranges for threatened caribou and helps give struggling timber producers a leg up in a troubled market by providing a path to green certification for their wood products and a steady supply of timber to rural mills.

Much of the attention in the discussion of climate change in recent years has centered on the destruction of the Amazon rainforest. But the boreal forest — the coniferous forest between the treeless Arctic and the more southerly rainforests in the Northern Hemisphere — stores more than a fifth of the total carbon banked in the Earths land surface.

Logging releases stored carbon into the atmosphere, where it magnifies the greenhouse gas effect that most scientists believe is warming the planet.

Conservation groups have mounted increasingly successful do-not-buy campaigns against the logging industry in Canada, where a third of the boreal forest is located. The groups have also said that logging threatens the survival ranges of migrating species such as caribou and the habitat for grizzly bears and wolves and the breeding grounds of 450 species of birds.