"Northern boreal forests are a crucial part of the global climate puzzle, comprising nearly 30 percent of Earth's forested area and storing at least 20 percent of its carbon",,,,,,,"The Keystone tree in the Boreal is the black spruce, a major source of the world's paper; home to caribou, snowshoe hare, lynx,wolves,sable and the nesting site for dozens of migratory bird species".........."North of the 49th latitude, climate change in the Boreal is causing snow to melt earlier and subsequently lengthening the growing season--:ironically(and in a dark and twisted way), potentially good news for Black Spruce annual tree growth".............."June and July is when most of the growth occurs in this forest and it is projected that by 2050, the growing season north of the "49th" will have expanded by 3 weeks, likely aiding the perpetuation of Black Spruce(abeit, in a smaller range than historically)" ............ "To the south of the 49th parallel, warming temperatures and the corressponding lengthened growing season are more likely to cause drought stress that could overwhelm black spruce"............So Harvard Forest's Neil Pederson is cautiously suggesting that climate change might have some sort of silver lining, predicting that the Upper Boreal might become a "sanctuary for the unique array of life that currently calls the entire Boreal home".............Still sucks as far as I'm concerned,,,,,,,,,,,,,Ever shrinking biodiversity,,,,ever shrinking habitat as we grew up knowing it------ all caused by our heavy handed footprint on the planet since the advent of agriculture 5000 years ago and the Industrial Revolution of the past 200 years

http://feedproxy.google.com/~r/sciencedaily/plants_animals/~3/39-rPRLSJ0U/160616150749.htm?utm_source=feedburner&utm_medium=email

Boreal forest.

Credit: Loïc D'Orangeville

Canadian forests a refuge as warming creeps north

Study says higher rainfall will help some trees survive

In the Canadian province of Quebec, a study of more than 26,000 trees across an area the size of Spain forecasts potential winners and losers in a changing climate.

The study, published today in the journal Science, shows that boreal forests in far-northern latitudes may one day act as a climate refuge for black spruce, the foundational tree for the northwoods ecosystem -- a major source of the world's paper; home to caribou, snowshoe hare, lynx, and sable; and nesting site for dozens of migratory bird species.

"During this century, the northwoods will experience some of Earth's largest increases in temperature," says Loïc D'Orangeville, postdoctoral researcher at Université du Québec à Montréal and Indiana University, who led the collaboration of scientists from six institutions in the U.S. and Canada.

Northern boreal forests are a crucial part of the global climate puzzle, comprising nearly 30 percent of Earth's forested area and storing at least 20 percent of its carbon. The study's tree ring analysis revealed these forests' sensitivity to changes in temperature and precipitation.

"A warming climate increases the amount of water boreal forests need to survive," explains D'Orangeville. "It's possible that only a relatively small part of North America's boreal forest will have enough water to compensate for the increased demand."

North of a certain latitude (broadly 49 degrees North), the study showed, warming melts snow earlier and lengthens the growing season: good news for tree growth. "Right now -- June and July -- is when most of the annual tree growth takes place in the boreal forest," says D'Orangeville. Climate models predict that by 2050, the growing season in the study area will have expanded by 3 weeks.

South of the 49th parallel, however, warming and the lengthened growing season are more likely to cause drought stress that could overwhelm black spruce. The researchers say this may explain increased tree mortality already being observed in the region.

"But as you move northwards, temperatures cool, and evaporation diminishes," says D'Orangeville. As climate warms through 2070, more than two-thirds of the forested territory just above the 49th parallel should still be showing a positive response.

"This part of the forest could adapt to climate change in our lifetime, if future warming stays below the temperature threshold," says Neil Pederson, co-author of the study and a senior ecologist at Harvard Forest. "But the future cannot be perfectly predicted." And, he cautions, unpredictable factors, such as the recent mega-fires in boreal regions of western Canada and Alaska, could disrupt this dynamic.

Still, the study offers a note of hope. "In a world where many ecological forecasts appear dire for plants, animals, and people," says Pederson, "identifying areas that could serve as potential havens for biodiversity during potentially tumultuous times is good news."

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Story Source:

The above post is reprinted from materials provided by Harvard University.Note: Materials may be edited for content and length.

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Journal Reference:

1. L. D’Orangeville et al. Northeastern North America as a potential refugium for boreal forests in a warming climate. Science, June 2016 DOI: 10.1126/science.aaf4951