INFOGRAPHIC

How the SPRUCE project is helping assess what the future holds for the world’s boreal forests

Simulating changing boreal forest climate conditions — in Minnesota

“There is simply nothing else like this in the world.”

Danielle Way, a plant biologist and associate professor at Western University in London, Ont., could be talking about the boreal forest — the Earth’s largest land biome, 75 per cent of Canada’s forest cover and the world’s biggest storehouse of carbon, the integrity and stability of which are crucial to the fight against climate change. But in fact, she’s describing the Spruce and Peatland Responses Under Changing Environments (SPRUCE) project, an 8.1-hectare whole-ecosystem boreal experiment initiated by Oak Ridge National Laboratory in 2014 in northern Minnesota’s Marcell Experimental Forest. There, in a set of acrylic enclosures built atop a black spruce and peat bog, more than 100 researchers — including Way and several other Canadians — are measuring how the trees, plants, soil, insects and micro-organisms respond to simulated climate conditions of tomorrow. The knowledge can help shape resource management planning and practices for forestry and recreation, as well as predict how climate change will affect biodiversity, conservation practices and the release of stored carbon in the boreal forest.

“By providing us with a picture of what our forests will look like in the next 80 years,” says Way, “SPRUCE can help us decide if that future is really where we want to go.” Here is a look inside one of the domes.

SPECIFIC PLOTS and sampling areas measure growth rates and other energy/production indicators for vegetation, soil, insects and micro-organisms. ALONG WITH HEATERS and the carbon dioxide supply, critical instruments inside a dome include sensors that measure light beyond the visible spectrum (to help gauge plant health); photosynthesis and respiration rates; CO2 and methane emissions and levels in the soil; below-ground temperatures and changes in moisture levels. VEGETATION IS THE SAME inside and out: three- to seven-metre-tall black spruce and larch trees; sphagnum and other mosses; and plants such as Labrador tea, bog rosemary, leatherleaf and cotton grass. TEN IDENTICAL acrylic-and-aluminum-frame opentopped enclosures are arranged among 17 plots on three short lanes connected by boardwalks. Each octagonal enclosure is eight metres high and 12 metres wide, and their open tops provide exposure to snow, rain and other environmental elements. IN FIVE ENCLOSURES, carbon dioxide levels match ambient levels; the other five are kept at 800 to 900 parts per million (roughly double present day). For both CO2 regimes, there are five soil and air temperature settings: ambient (outside), and increases of +2.25 C, +4.5 C, +6.75 C and +9 C.