2008 Joint Annual Meeting (5-9 Oct. 2008): Carbon Flux and Transformation Across the Arctic Coastline of Alaska.

699-25 Carbon Flux and Transformation Across the Arctic Coastline of Alaska.



Wednesday, 8 October 2008
George R. Brown Convention Center, Exhibit Hall E
Chien-Lu Ping1, Gary Michaelson1, Lorene Lynn1, Torre Jorgenson2 and Fugen Dou3, (1)Agriculture and Forestry Experiment Station, University of Alaska Fairbanks, 533 E. Fireweed Ave., Palmer, AK 99645
(2)ABR. Inc., Fairbanks, AK 99708
(3)Soils, Water and Atmosphereic Sciences, Universiti of California-Davis, 500 Orchard Pkwy Circle #5315, Davis, CA 95616
Over the past decades the accelerated erosion of the Arctic coastline has been the focus of scientists, land managers, policy makers and the natives communities settled along the Arctic coast.  The objectives of this project are to monitor the erosion rate, to estimate the amount and fate of the organic carbon in the tundra soils and underlying permafrost eroded into the Arctic Ocean. Soil and permafrost along the coastal bluffs were described and sampled in 50 study sites along the 3060 km coastline from Pt Barrow to the Alaska-Canadian boundary. The estimated average erosion rate is 2 meters per year which transforms to about 600 hectares of land lost to the Arctic Ocean per year. The average organic carbon content of the soils and the underlying permafrost is 70 kg per square meter. Based on an average bulk density of 1.4 g cm-3, there is estimated 420,000 tons of carbon entering into the Arctic Ocean. The thawing permafrost releases 550,000 kg of CO2 and 6500 kg of methane directly into the atmosphere. The fate of the eroded carbon is being studied.