2019 journal article
Assessing the distribution of labile organic carbon from diverse depositional environments on the West Antarctic Peninsula shelf
DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS, 156.
author keywords: West Antarctic Peninsula; Labile organic carbon; Radiocarbon; Bioturbation; Diagenesis; Marine sedimentary processes
UN Sustainable Development Goal Categories
14. Life Below Water
(Web of Science; OpenAlex)
Source: Web Of Science
Added: March 16, 2020
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.