TY - JOUR T1 - A decrease in discharge-normalized DOC export by the Yukon River during summer through autumn JF - Geophysical Research Letters Y1 - 2005 A1 - Striegl, R. G. A1 - Aiken, G. R. A1 - Dornblaser, M. M. A1 - Raymond, P. A. A1 - Wickland, K. P. KW - alaska KW - arctic-ocean KW - climate-change KW - CO2 KW - discontinuous permafrost KW - dissolved organic-carbon KW - flux KW - MATTER KW - tundra AB - Climate warming is having a dramatic effect on the vegetation distribution and carbon cycling of terrestrial subarctic and arctic ecosystems. Here, we present hydrologic evidence that warming is also affecting the export of dissolved organic carbon and bicarbonate (DOC and HCO3-) at the large basin scale. In the 831,400 km(2) Yukon River basin, water discharge (Q) corrected DOC export significantly decreased during the growing season from 1978 - 80 to 2001 - 03, indicating a major shift in terrestrial to aquatic C transfer. We conclude that decreased DOC export, relative to total summer through autumn Q, results from increased flow path, residence time, and microbial mineralization of DOC in the soil active layer and groundwater. Counter to current predictions, we argue that continued warming could result in decreased DOC export to the Bering Sea and Arctic Ocean by major subarctic and arctic rivers, due to increased respiration of organic C on land. VL - 32 SN - 0094-8276 UR - http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=Alerting&SrcApp=Alerting&DestApp=WOS&DestLinkType=FullRecord;UT=WOS:000233354500009 IS - 21 N1 - 985cuTimes Cited:163 Cited References Count:28 JO - Geophys Res Lett ER -