Cesium-137 inventories in Alaskan Tundra, lake and marine sediments: An indicator of recent organic material transport?

• Main Authors: Grebmeier, J.M., Cooper, L.W. |, Larsen, I.L., Solis, C., Olsen, C.R.
• Language: unknown
• Published: 2008
• Subjects: 54 ENVIRONMENTAL SCIENCES; CESIUM 137; RADIOECOLOGICAL CONCENTRATION; ALASKA; TUNDRA; SEDIMENTS; DEPOSITION; ORGANIC MATTER; CARBON CYCLE; SAMPLING; ENVIRONMENTAL TRANSPORT; WATERSHEDS; Arctic; Lake Inlet; Prudhoe Bay; Tundra; Alaska
• Online Access: http://www.osti.gov/servlets/purl/10170969; https://www.osti.gov/biblio/10170969

Tundra sampling was accomplished in 1989--1990 at Imnavait Creek, Alaska (68{degree}37` N, 149{degree}17` W). Inventories of {sup 137}Cs (102--162 mBq/cm{sup 2}) are close to expectations, based upon measured atmospheric deposition for this latitude. Accumulated inventories of {sup 137}Cs in tundra decrease by up to 50% along a transect to Prudhoe Bay (70{degree}13` N, 148{degree}30` W). Atmospheric deposition of {sup 137}Cs decreased with latitude in the Arctic, but declines in deposition would have been relatively small over this distance (200 km). This suggests a recent loss of {sup 137}Cs and possibly associated organic matter from tundra over the northern portions of the transect between Imnavait Creek and Prudhoe Bay. Sediments from Toolik Lake (68{degree}38` N, 149{degree}38` W) showed widely varying {sup 137}Cs inventories, from a low of 22 mBq/cm{sup 2} away from the lake inlet, to a high between 140 to >200 mBq/cm{sup 2} near the main stream inflow. This was indicative of recent accumulation of cesium and possibly organic material associated with it in arctic lakes, although additional sampling is needed.