US DOE launches SPRUCE to measure carbon sinks under climate change pressure
In Michigan, the SPRUCE (Spruce and Peatland Responses Under Climatic and Environmental Change) project launched today about 25 miles north of Grand Rapids. The site consists of about seven acres of raised bog in the peatlands of the Chippewa National Forest.
With the ability to control heating of the air and soil within the enclosures to a depth of two meters, scientists hope to gain an understanding of the possible effects of projected higher temperatures on vegetation and ecosystems.
Experimental work in the 8.1-ha S1 bog will be a climate change manipulation focusing on the combined responses to multiple levels of warming at ambient or elevated CO2 (eCO2) levels. The experiment provides a platform for testing mechanisms controlling the vulnerability of organisms, biogeochemical processes and ecosystems to climatic change (e.g., thresholds for organism decline or mortality, limitations to regeneration, biogeochemical limitations to productivity, the cycling and release of CO2 and CH4 to the atmosphere).
While peatlands cover about 3 percent of Earth’s land surface, they contain up to 33 percent of the global soil carbon pool. Although that carbon dioxide has been trapped in the cold oxygen-poor environment for thousands of years, warming conditions threaten to see peatlands release large amounts of carbon dioxide and methane. This occurs through a combination of enhanced decomposition and aeration of surface peats.
Ten open-topped transparent enclosures – 12 meters in diameter by 8 meters high — are the laboratories for the experiments to assess the ecological responses. The enclosures, superimposed on a belowground corral that isolates the peatland, will host measurements of microbial communities, moss populations, various higher plant types and some insect groups.
“SPRUCE is the first experiment to test the combination of warming and elevated carbon dioxide on carbon-rich peatland ecosystems,” said Randy Kolka, team leader and research soil scientist with the Forest Service, a partner in the project.
“Peatlands contain a disproportionate amount of carbon compared to other ecosystems, and understanding their sensitivity to climate change will be critical to predict what happens to the balance between carbon stored in peatlands and the amount of carbon dioxide and methane in the atmosphere.”
Category: Research
