Sinkers or floaters? Contribution from salp pellets to the export flux during a large bloom event in the Southern Ocean

Iversen, Morten Hvitfeldt; Pakhomov, Evgeny A.; Hunt, Brian P. V.; Jagt, Helga van der; Wolf‐Gladrow, Dieter; Klaas, Christine

doi:10.1016/j.dsr2.2016.12.004

Cited by 72 publications

(70 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Compared to previous studies (Pakhomov et al, 2006;Phillips et al, 2009), low to medium abundances of salp were observed in the upper 250 m of the water column (19.8 to 54.4 ind m −2 ; Iversen et al, 2016). Particulate organic carbon per day produced as salp FPs was 3.3 mg C.m −2 , this is equivalent to salp ingesting and releasing daily only ≈ 0.2% of the net primary production (NPP) estimated in the study area (1751 mg C m −2 , Hoppe et al, 2015).…”

Section: Discussionmentioning

confidence: 61%

“…Salp FP fluxes were collected with free-drifting sediment traps at 100 and 300 m and a detailed description is provided by Iversen et al (2016). Salp FPs are very large and fairly easy to identify.…”

Section: Salp Fp Fluxesmentioning

confidence: 99%

“…FP dFe_PROD were calculated using the Fe:C ratio of 225 µmol Fe mol −1 C −1 . Total POC fluxes and C fluxes generated by salp FPs were reported from Roca Martí et al (2016) and Iversen et al (2016), respectively. order of magnitude below the standing stock, suggesting that the release observed of dSi(OH) 4 (corresponding to our three physico-chemical experimental treatments: "freezer, " "dark, " and "VIS") would not have substantially contribute to the maintenance of the observed diatom bloom.…”

Section: Impact Of Salp Fps On Macronutrient Concentrationsmentioning

confidence: 99%

“…The FPs were either placed in a 100 mL trace metal clean low density polyethylene (LDPE) bottle filled with FSW for the on-board experiments or stored at −80 • C for laboratory experiments. The salp FPs were compact looking pellets packed with particles (described as "type 1" in Iversen et al, 2016).…”

Section: Sample Collectionmentioning

confidence: 99%

See 3 more Smart Citations

First Evaluation of the Role of Salp Fecal Pellets on Iron Biogeochemistry

et al. 2017

Self Cite

View full text Add to dashboard Cite

Planktonic grazers such as salps may have a dominant role in iron (Fe) cycling in surface waters of the Southern Ocean (SO). Salps have high ingestion rates and egest large, fast sinking fecal pellets (FPs) that potentially contribute to the vertical flux of carbon. In this study, we determined the impact of FPs from Salpa thompsoni, the most abundant salp in the SO, on Fe biogeochemistry. During the Polarstern expedition ANT-XXVII/3, salps were sampled from a large diatom bloom area in the Atlantic sector of the SO. Extensive work on carbon export and salp FPs export at the sampling location had shown that salps were a minor component of zooplankton and were responsible for only a 0.2% consumption of the daily primary production. Furthermore, at 100 m, export efficiency of salp FPs was ∼2-3 fold higher than that of the bulk of sinking particulate organic carbon (POC). After collection, salps were maintained in 200 µm screened seawater and their FPs were collected for further experiments. To investigate whether the FPs release Fe and/or Fe-binding ligands into the filtered seawater (FSW) under different experimental conditions, they were either incubated in the dark or under full sunlight at in situ temperatures for 24 h, or placed into the dark after a freeze/thaw treatment. We observed that none of the treatments caused release of dissolved Fe (dFe) or strong Fe ligands from the salp FPs. However, humic-substance like (HS-like) compounds, weak Fe ligands, were released at a rate of 8.2 ± 4.7 µg HS-like FP −1 d −1 . Although the Fe content per salp FP was high at 0.33 −1 ± 0.02 nmol dFe FP , the small contribution of salps to the zooplankton pool resulted in an estimated dFe export flux of 11.3 nmol Fe m −2 d −1 at 300 m. Since salp FPs showed an export efficiency at 100 m well above that shown by the bulk of sinking POC, our results suggest that in those areas of the SO where salps play a major role in the grazing of primary production, they could be actively contributing to the depletion of the dFe pool in surface water.

show abstract

Section: Discussionmentioning

confidence: 61%

Section: Salp Fp Fluxesmentioning

confidence: 99%

Section: Impact Of Salp Fps On Macronutrient Concentrationsmentioning

confidence: 99%

Section: Sample Collectionmentioning

confidence: 99%

See 2 more Smart Citations

First Evaluation of the Role of Salp Fecal Pellets on Iron Biogeochemistry

et al. 2017

Self Cite

View full text Add to dashboard Cite

show abstract

“…However, recent studies are challenging the role of macrozooplankton feces to efficiently transfer carbon to the deep sea in the WG. Iversen et al () showed that while 30% of the salp fecal pellets were collected by sediment traps at 100 m, only 13% of the pellets were caught at 300 m. The authors suggested retention of the carbon in the upper layers of the ocean, due to pellet break up, presumably by zooplankton grazing. Hence, salp fecal pellets could also have a role in recycling organic matter in the upper mesopelagic waters, a process not very well understood (Iversen et al, ).…”

Section: Biology Ii: Food Web Of the Wgmentioning

confidence: 99%

The Weddell Gyre, Southern Ocean: Present Knowledge and Future Challenges

Vernet

Geibert

Hoppema

et al. 2019

Reviews of Geophysics

148

147

View full text Add to dashboard Cite

The Weddell Gyre (WG) is one of the main oceanographic features of the Southern Ocean south of the Antarctic Circumpolar Current which plays an influential role in global ocean circulation as well as gas exchange with the atmosphere. We review the state‐of‐the art knowledge concerning the WG from an interdisciplinary perspective, uncovering critical aspects needed to understand this system's role in shaping the future evolution of oceanic heat and carbon uptake over the next decades. The main limitations in our knowledge are related to the conditions in this extreme and remote environment, where the polar night, very low air temperatures, and presence of sea ice year‐round hamper field and remotely sensed measurements. We highlight the importance of winter and under‐ice conditions in the southern WG, the role that new technology will play to overcome present‐day sampling limitations, the importance of the WG connectivity to the low‐latitude oceans and atmosphere, and the expected intensification of the WG circulation as the westerly winds intensify. Greater international cooperation is needed to define key sampling locations that can be visited by any research vessel in the region. Existing transects sampled since the 1980s along the Prime Meridian and along an East‐West section at ~62°S should be maintained with regularity to provide answers to the relevant questions. This approach will provide long‐term data to determine trends and will improve representation of processes for regional, Antarctic‐wide, and global modeling efforts—thereby enhancing predictions of the WG in global ocean circulation and climate.

show abstract

In situ Particle Measurements Deemphasize the Role of Size in Governing Particle Sinking Velocity

Williams

Giering

2022

Preprint

View full text Add to dashboard Cite

Sinkers or floaters? Contribution from salp pellets to the export flux during a large bloom event in the Southern Ocean

Cited by 72 publications

References 50 publications

First Evaluation of the Role of Salp Fecal Pellets on Iron Biogeochemistry

First Evaluation of the Role of Salp Fecal Pellets on Iron Biogeochemistry

The Weddell Gyre, Southern Ocean: Present Knowledge and Future Challenges

In situ Particle Measurements Deemphasize the Role of Size in Governing Particle Sinking Velocity

Contact Info

Product

Resources

About