Project Details
The Spruce and Peatland Responses Under Changing Environments (SPRUCE) experiment is the primary component of the DOE Terrestrial Ecosystem Science Scientific Focus Area led by ORNL, focused on terrestrial ecosystems and the mechanisms that underlie their responses to ecosystem change. The experimental work is conducted in a Picea mariana [black spruce] – Sphagnum spp. bog forest in northern Minnesota, 40 km north of Grand Rapids, in the USDA Forest Service Marcell Experimental Forest (MEF). The site is located at the southern margin of the boreal peatland forest. It is an ecosystem considered especially vulnerable to environmental change, that stores a large amount of carbon, and is anticipated to be near its tipping point.
Experimental work in the 8.1-ha S1 bog is focused 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 environmental 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).
The manipulation evaluates the response of the existing biological communities to a range of warming levels from ambient to +9°C, provided via large, modified open-top chambers. The ambient and +9°C warming treatments are also conducted at eCO2 (in the range of 800 to 900 ppm). Both direct and indirect effects of these experimental perturbations will be analyzed to develop and refine models needed for full Earth system analyses.
For more information on SPRUCE, please visit https://mnspruce.ornl.gov/project/overview.
