Abstract
Abstract. To study sinking particle sources and dynamics, sediment traps were deployed at three sites in the Amundsen Sea for 1 year from February–March 2012 and at one site from February 2016 to February 2018. Unexpectedly, large benthic invertebrates were found in three sediment traps deployed 130–567 m above the sea floor. The organisms included long and slender worms, a sea urchin, and juvenile scallops of varying sizes. This is the first reported collection of these benthic invertebrates in sediment traps. The collection of these organisms, predominantly during the austral winter, and their intact bodies suggests they were trapped in anchor ice, incorporated into the overlying sea ice, and subsequently transported by ice rafting. The observations imply that anchor ice forms episodically in the Amundsen Sea and has biological impacts on benthic ecosystems. An alternative hypothesis that these organisms spend their juvenile period underneath the sea ice and subsequently sink to the seafloor is also suggested.
Highlights
The majority of the Amundsen Shelf in the Antarctic is perennially covered with sea ice, except for the two seasonal polynyas
Intensive flux of particulate organic carbon to the seafloor occurs in the austral summer, while the sea interior is in starvation in the other seasons (Ducklow et al, 2015; Kim et al, 2015, 2019)
Station K4 is located within the seasonal Amundsen Sea Polynya, and the sea ice concentration there decreases to zero in summer (Fig. 2)
Summary
The majority of the Amundsen Shelf in the Antarctic is perennially covered with sea ice, except for the two seasonal polynyas. Sediment traps were deployed in the Amundsen Sea to study sinking material flux and composition. Sampling occurred from February and March 2012 for 1 year at three locations along the paleoglacier-carved Dotson Trough and from February 2016 to February 2018 in a trap deployed in front of the eastern Getz Ice Shelf, near Duncan Peninsula. At three locations macrobenthic organisms were found in the sampling cups, including long and slender worms, a sea urchin, and juvenile scallops of varying sizes. This is the first reported collection of these benthic invertebrates in sediment traps
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
