Intense deposition and rapid processing of seafloor phytodetritus in a glaciomarine fjord, Andvord Bay (Antarctica)

Seasonal dispersal of fjord meltwaters as an important source of iron to coastal Antarctic phytoplankton

“…The microplankton class was sparingly present in the Fall, however, benthic cameras captured a large sedimentation event of marine aggregates indicative of a large diatom bloom in late-January. The export of biogenic particles from the surface also showed a distinct seasonality indicated by increased Chlorophyll-a pigment content in seafloor sediment cores (Ziegler et al, 2020), as well as higher respiration rates from chamber incubation experiments in the Fall compared to Spring (data not shown), although no indication of sulfate reduction was observed in sediment box and Kasten cores, suggesting that oxygen, nitrate, and metal oxides were sufficient to oxidize organic matter within the upper sediments (C. Smith pers. comm.…”

“…estimated spatially variable efflux spanning 0.028-8.2 µmol m -2 d -1 based on water column dFe profiles (Marsay et al, 2014). Abundant epibenthic fauna found within Andvord (Ziegler et al 2017(Ziegler et al , 2020 would introduce oxygen to the upper few centimeters of the sediments through bioturbation and reduce the efflux of reduced metals (Severmann et al, 2010). Taylor ).…”

“…We present trace metal results from two expeditions (December 2015 and April 2016) to Andvord Bay, a cold glacio-marine fjord located mid-latitude along the WAP. This study is part of the FjordEco project which assessed the ecosystem function and seasonality of Andvord Bay (Pan et al 2019;Pan et al 2020;Ziegler et al 2020;Eidam et al 2019;Lundesgaard et al 2020Lundesgaard et al , 2019Hahn-Woernle et al 2020). The WAP is host to the most extensive collection of glaciomarine fjords on the at -20°C until complete digestion by HNO3/HF mixture.…”

The Terebelliformia-Recent Developments and Future Directions

“…All the terebelliforms are selective surface deposit feeders [68] gathering food particles with the buccal tentacles, and then conveying these to the mouth, through the ciliated longitudinal tentacular groove. This trophic mode largely modifies marine benthic environments by reworking large amounts of sediments [69] and directly affects their physical and chemical properties [70,71]. Particularly, terebelliforms have a great impact on the amount of organic matter at the water-sediment interface, modifying local hydrodynamics and sediment cohesion [72].…”

Antarctic ecosystem responses following ice‐shelf collapse and iceberg calving: Science review and future research

“…A major challenge is to document ecosystem responses at all levels of biological organization (genome to pan‐Antarctic), and combine genomics/DNA approaches with multi‐taxon studies that integrate taxonomic, biogeochemical, genomic, and community data followed by matching biological data with fluxes/transports measured by physical oceanographers, geochemists, and geologists (e.g., Halanych & Mahon, 2018). We also need a better understanding of the mechanistic linkages between climate, sea ice and ice shelves, ice sheets and icebergs, biogeochemical processes, food webs and organism interactions, and population and community dynamics (e.g., Lundesgaard et al, 2020; Ziegler, Cape, et al, 2020; Ziegler, Hahn‐Woernle, et al, 2020). Linkages with glaciology, physical oceanography, biology, and ecological interactions are critical as both drivers and impacts of ice‐shelf loss (Ducklow, 2008; Ducklow et al, 2007; Massom & Stammerjohn, 2010).…”