HR: 14:21h
AN: OS43B-03 INVITED     [Abstracts]
TI: Flux and Transformation of Soil Organic Carbon Across the Eroding Coastline of Northern Alaska, Preliminary Results
AU: * Jorgenson, T
EM: tjorgenson@abrinc.com
AF: ABR, Inc., PO Box 80410, Fairbanks, AK 99708 United States
AU: Ping, C
EM: pfclp@uaa.alaska.edu
AF: University of Alaska Fairbanks, PO Box 755900, Fairbanks, AK 99775
AU: Guo, L
EM: guol@iarc.uaf.edu
AF: University of Alaska Fairbanks, PO Box 755900, Fairbanks, AK 99775
AU: Shur, Y
EM: ffys@uaf.edu
AF: University of Alaska Fairbanks, PO Box 755900, Fairbanks, AK 99775
AU: Michaelson, G
EM: pngjm@uaa.alaska.edu
AF: University of Alaska Fairbanks, PO Box 755900, Fairbanks, AK 99775
AU: Dou, F
EM: fdou@iarc.uaf.edu
AF: University of Alaska Fairbanks, PO Box 755900, Fairbanks, AK 99775
AU: Tumskoy, V
EM: ffys@uaf.edu
AF: University of Alaska Fairbanks, PO Box 755900, Fairbanks, AK 99775
AU: Kanevsky, M
EM: ffys@uaf.edu
AF: University of Alaska Fairbanks, PO Box 755900, Fairbanks, AK 99775
AU: Brown, J
EM: jerrybrown@igc.org
AF: International Permafrost Association, PO Box 7, Woods Hole, MA 02543 United States
AU: Kodial, P
EM: ffys@uaf.edu
AF: University of Alaska Fairbanks, PO Box 755900, Fairbanks, AK 99775
AB: Large amounts of soil organic carbon (SOC) that have been long sequestered in Holocene deposits along the ~2000 km mainland coast of northern Alaska are being rapidly released by coastal erosion. This eroded SOC becomes available for biogeochemical cycling and makes a substantial, but poorly known, contribution to marine ecosystems and to CO2 and methane emissions to the atmosphere. The annual flux of SOC across the eroding coastline has been estimated to be 1.8x105 Mg-C/y, but initial estimates are imprecise due to the high variability of carbon stocks, erosion rates, and ground ice content. To provide more accurate estimates of SOC flux, we sampled 24 of 50 extensive sites and 6 of 9 intensive sites across the Alaska Beaufort Sea coast in 2005 to quantify the nature and abundance of SOC, sediment stratigraphy, ice content and bulk density, and erosion rates. The variability in carbon and permafrost characteristics was strongly related to depositional environments. To assess the transformation of SOC as it crosses the land/ocean interface, the partitioning of SOC between dissolved and particulate phases, and decomposition rates are being examined in the laboratory experiments. Finally, a network of village-based monitoring sites has been developed to monitor annual variability in coastal processes.
DE: 0428 Carbon cycling (4806)
DE: 0442 Estuarine and nearshore processes (4235)
DE: 0460 Marine systems (4800)
DE: 0486 Soils/pedology (1865)
DE: 0702 Permafrost (0475)
SC: Ocean Sciences [OS]
MN: Fall Meeting 2005