Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
4536718 | Deep Sea Research Part II: Topical Studies in Oceanography | 2012 | 9 Pages |
To evaluate the efficiency of biological pump and carbon sequestration content on Arctic shelf, estimations of POC export fluxes derived from 234Th/238U disequilibrium were made during the 3rd Chinese National Arctic Research Expedition (CHINARE-3) from July 12 to September 22, 2008. The 234Th analysis was based on small volume MnO2 co-precipitation and β-counting method. Great deficits of 234Th to 238U were observed widely over Chukchi shelf, with an average 234Th/238U activity ratio of 0.64±0.28, resulting from intense particle scavenging. The average POC export fluxes in the entire study area, shelf and slope area were 24.9±23.3, 29.5±23.0 and 2.1±0.5 mmol C m−2 d−1, respectively, resulting in that 21% of the primary production on average was exported to the benthos. Comparing with steady state model, non-steady-state model was recommended to derive a more accurate particulate 234Th export flux in a rapidly changing environment in the high latitude areas.