Details

Autor(en) / Beteiligte

• Taylor, Richard S.
• DeMaster, David J.
• Burdige, David J.

Titel

Assessing the distribution of labile organic carbon from diverse depositional environments on the West Antarctic Peninsula shelf

Ist Teil von

• Deep-sea research. Part I, Oceanographic research papers, 2020-02, Vol.156, p.103166, Article 103166

Ort / Verlag

Elsevier Ltd

Erscheinungsjahr

2020

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The seabed distributions of labile organic carbon (LOC), i.e., recently produced organic matter from marine plankton, were studied in a variety of depositional environments on the West Antarctic Peninsula continental shelf using the naturally occurring radioisotopes, 14C, 210Pb and 234Th. The effects of bioturbation on the LOC pool were assessed on short-term (seasonal, using 234Thxs within the upper, 2–5 cm) and long-term (decadal, using 210Pbxs from 3-22 cm) timescales to generate LOC degradation coefficients (k) and mean residence times (MRT or τ-LOC) as a function of depth within the sediment column. Based on 234Th distributions, mixing coefficients (Db) ranged from 2 cm2/y to 36 cm2/y, which resulted in LOC MRT values that varied from 0.8y to 9.8y. Based on 210Pb distributions, Db values at depth ranged from 0.2 cm2/y to 1.8 cm2/y, resulting in MRT values that varied from 32y to 4900y. Along the West Antarctic Peninsula, seabed inventories of LOC varied between 17-70 mg/cm2. Bulk LOC becomes less reactive and ages with time during resuspension and transport across the shelf and as LOC is transported deeper within the sediment column by infaunal feeding activities. •Field verified labile organic carbon in sedimentary cores.•Antarctic Peninsula sediment carbon inventories evaluated.•Antarctic peninsula depositional environment sediment dynamics compared.