Major fine-scale spatial heterogeneity in accumulation of gelatinous carbon fluxes on the deep seabed

作者：Henk‐Jan Hoving, Antje Boëtius, Katherine Dunlop, Jens Greinert, Matthias Haeckel, Daniel O. B. Jones, Erik Simon‐Lledó, Yann Marcon, Tanja Stratmann, Inken Suck, Andrew K. Sweetman, Autun Purser · 发表于：Frontiers in Marine Science · 年份：2023 · DOI：10.3389/fmars.2023.1192242 · 被引用次数：15 · 研究领域：Marine Biology and Ecology Research、Marine and coastal ecosystems、Isotope Analysis in Ecology

Abyssal plain communities rely on the overlying water column for a settling flux of organic matter. The origin and rate of this flux as well as the controls on its fine-scale spatial distribution following seafloor settlement are largely unquantified. This is particularly true across regions where anthropogenically-induced seafloor disturbance has occurred. Here, we observed, quantified and mapped a mass deposition event of gelatinous zooplankton carcasses (pyrosomes) in July-September 2015 across one such physically disturbed region in the Peru Basin polymetallic nodule province (4150 m). Seafloor in this area was disturbed with a plough harrow in 1989 (as part of the DISCOL experiment) causing troughs in the sediment. Other parts were disturbed with an epibenthic sled (EBS) during a cruise in 2015 resulting in steep-walled, U-shaped troughs. We investigated two hypotheses: a) gelatinous food falls contribute significantly to the abyssal plain carbon pump and b) physical seafloor disturbance influences abyssal distribution of organic matter. We combined optical and bathymetric seafloor observations, to analyze pyrosome distribution on seabeds with different levels of disturbance. 2954 pyrosome colonies and associated taxa were detected in > 14,000 seafloor images. The mean regional carbon (C) deposition associated with pyrosome carcasses was significant compared to the flux of particulate organic C (182 to 1543%), and the total respired benthic C flux in the DISCOL Ex...