Spruce Tree Species Shifting West

Dan Bross, KUAC – Fairbanks

Results of tree survey show spruce species declining in the Interior, and increasing in
Western Alaska and other areas previously at the fringe off the conifer species range. The recently released study uses satellite images and tree ring analysis to look at black and white spruce, which make up 70 percent of boreal forest trees.  Co-author of an article on the study, University of Alaska Fairbanks Ecology Professor Glenn Juday says the shift in the boreal forest is being driven by climate change.

Juday says Interior summer temperatures have gone up an average of 2 degrees Celsius and are continuing to increase.  He says another 1 to 1 and a half degrees and the region will reach a point where spruce cannot survive in most areas.  While the average increase is significant, Juday says the real tree killer is acute hot dry spells.

Juday says Alaska is seeing one of the first well documented biome shifts.  An article on the study is published in the scientific journal Ecology letters.

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