BE/CBC: Biocomplexity Associated with the Response of Tundra Carbon Balance to Warming and Drying Across Multiple Spatial and Temporal Scales

• Investigators: Walt Oechel, Craig E. Tweedie, John Kimball.
• Funding Agency: US National Science Foundation ASSP0421588
• Project Length: September 2004 – August 2008
• SEL Participants: Santonu Goswami, Edith Velasco, Sergio Vargas
• Web sites with more information on this project: www.baidims.org.

Summary:

Intellectual Merit: This proposal will examine how biological and physical processes interact to control carbon uptake, storage and release in Arctic tundra ecosystems and how the self-organizing nature of these interactions varies across multiple spatial and temporal scales. Approximately 25% of the world’s soil organic carbon reservoir is stored at high northern latitudes in permafrost and seasonally-thawed soils in the Arctic, a region that is currently undergoing unprecedented warming and drying, as well as dramatic changes in human land use. Understanding how changes in annual and inter-annual ecosystem productivity interact and potentially offset the balance and stability of the Arctic soil carbon reservoir is of utmost importance to global climate change science. If there is a net loss of soil carbon to the atmosphere in the form of greenhouse gases (namely CO2 and CH4), greenhouse warming could be enhanced. This non-linear, potentially positive feedback response could very quickly cause Arctic terrestrial ecosystems to function in a manner not known to us from the late Holocene and with globally significant implications.

The proposed activities benefit from a foundation and wealth of international and national carbon cycle research undertaken in northern Alaska and other Arctic regions over the past three decades. We will initiate a comprehensive study involving an integrated framework of multi-scale aircraft and satellite remote sensing, micrometeorological and CO2 and CH4 flux measurements and hydroecological process model simulations over a 350km North-South transect spanning the dominant Arctic topographic and land cover units of northern Alaska. The study region encompasses many long-term measurement sites that have been in place for 5 to 10 years. We will expand these observations to include an extensive soil moisture manipulation involving a 60 hectare tundra flooding/draining experiment near Barrow Alaska on the Arctic Coastal Plain. The objective of this study is to quantify linkages between soil moisture and carbon uptake, storage and release over multiple spatial (microbial to landscape) and temporal (minutes to decades) scales.Only by increasing the spatial extent of our experimental manipulations and the duration of our observational time series can we better understand and predict the effect of scale on the complex coupling within Arctic ecosystems; namely, how small scale processes participate as components of higher scale phenomenon and how higher scale phenomenon constrain the former lower scale processes. This knowledge will improve our understanding of the current behavior and potential response of arctic tundra to global change, resulting in better predictions of feedbacks to climate and the global carbon cycle.

Broader Impacts: National and international science will benefit substantially from this project, as will local residents, who are primarily Native Iñupiat Eskimo. The landscape manipulation site will be available to other interested scientists, providing a regional resource for multi- and interdisciplinary studies of Arctic change. The project will foster a new collaborative, multidisciplinary team of experts comprised of new and experienced arctic and non-arctic researchers, and students with direct links to NSF, DOE, and NASA projects including Ameriflux, SpecNet, ITEX, SEARCH, CEON and with additional planning, ORION. Northern Alaska residents will benefit from the symbiotic ties between community, local students, educators, and project investigators. The project’s formal and informal educational outreach will build on the already highly successful NSF-funded GK-12 PISCES educational activities at Barrow, Atqasuk and other rural villages, the Toolik Lake LTER Schoolyard project and NSF.s REU program. Building on past development, near real-time data from field instrumentation will be included in classroom and mobile displays at the Iñupiat Heritage Center and the Ukpeagvik Iñupiat Corporation Science Center.

Research findings also will be made available to policymakers and land managers to promote sustainable and minimal impact development in northern Alaska, where cumulative impacts threaten large areas of tundra. Through activities such as IPCC, ICIA and state and local briefings, the research described here will benefit from the BEO.s planned developments (new Global Change Facility, Education Center, wireless backbone, boardwalks, power, etc.) and will benefit the BEO by initiating the installation of many of these improvements. The baseline data from this project and the initiation of a long-term manipulation will benefit future research on the BEO and broader pan-Arctic region.