Smoke from fire BNZ LTER

Smoke from a forest fire in an Alaskan boreal forest near Bonanza Creek LTER

browsing by vertebrate herbivores

Browsing by snowshoe hares and moose have dramatic top-down influences on vegetation composition, successional dynamics, and ecosystem function throughout interior Alaska.

longer snow free season

Recent models indicate that lengthening of the snow-free season and associated declines in surface albedo constitutes the largest positive feedback to climate warming in the boreal forest.

thawing permafrost

Increases in air temperatures and depth of insulating snow cover during winter are accelerating the rate of permafrost thaw. In areas of ice-rich permafrost, widespread thermokarst is having significant consequences for biogeochemical cycling and surface hydrology.

severe fires shifts

A recent shift in the Alaska fire regime has increased the frequency and size of high-severity fires that combust deep organic layers, exposing mineral soil and favoring the invasion of hardwoods. Within the BNZ LTER Regional Site Network, many sites that were dominated by black spruce prior to burning in 2004 have now converted to dense birch stands with very different vegetation and ecosystem characteristics (BD1 site).