Carbon export and transfer to depth across the Southern Ocean Great Calcite Belt
Sequestration of carbon by the marine biological pump depends on the processes that alter, remineralize, and preserve particulate organic carbon (POC) during transit to the deep ocean. Here, we present data collected from the Great Calcite Belt, a calcite-rich band across the Southern Ocean surface,...
| Main Authors: | , , , , , , |
|---|---|
| Other Authors: | |
| Format: | Article |
| Language: | en_US |
| Published: |
Copernicus GmbH
2015
|
| Online Access: | http://hdl.handle.net/1721.1/98111 https://orcid.org/0000-0001-9127-9884 |
| _version_ | 1811093081336840192 |
|---|---|
| author | Lam, P. J. Balch, W. M. Auro, M. E. Pike, S. Drapeau, D. Bowler, B. Rosengard, Sarah Zhou |
| author2 | Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences |
| author_facet | Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Lam, P. J. Balch, W. M. Auro, M. E. Pike, S. Drapeau, D. Bowler, B. Rosengard, Sarah Zhou |
| author_sort | Lam, P. J. |
| collection | MIT |
| description | Sequestration of carbon by the marine biological pump depends on the processes that alter, remineralize, and preserve particulate organic carbon (POC) during transit to the deep ocean. Here, we present data collected from the Great Calcite Belt, a calcite-rich band across the Southern Ocean surface, to compare the transformation of POC in the euphotic and mesopelagic zones of the water column. The [superscript 234]Th-derived export fluxes and size-fractionated concentrations of POC, particulate inorganic carbon (PIC), and biogenic silica (BSi) were measured from the upper 1000 m of 27 stations across the Atlantic and Indian sectors of the Great Calcite Belt. POC export out of the euphotic zone was correlated with BSi export. PIC export was not, but did correlate positively with POC flux transfer efficiency. Moreover, regions of high BSi concentrations, which corresponded to regions with proportionally larger particles, exhibited higher attenuation of > 51 μm POC concentrations in the mesopelagic zone. The interplay among POC size partitioning, mineral composition, and POC attenuation suggests a more fundamental driver of POC transfer through both depth regimes in the Great Calcite Belt. In particular, we argue that diatom-rich communities produce large and labile POC aggregates, which not only generate high export fluxes but also drive more remineralization in the mesopelagic zone. We observe the opposite in communities with smaller calcifying phytoplankton, such as coccolithophores. We hypothesize that these differences are influenced by inherent differences in the lability of POC exported by different phytoplankton communities. |
| first_indexed | 2024-09-23T15:39:23Z |
| format | Article |
| id | mit-1721.1/98111 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T15:39:23Z |
| publishDate | 2015 |
| publisher | Copernicus GmbH |
| record_format | dspace |
| spelling | mit-1721.1/981112022-10-02T03:09:53Z Carbon export and transfer to depth across the Southern Ocean Great Calcite Belt Lam, P. J. Balch, W. M. Auro, M. E. Pike, S. Drapeau, D. Bowler, B. Rosengard, Sarah Zhou Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Woods Hole Oceanographic Institution Rosengard, Sarah Zhou Sequestration of carbon by the marine biological pump depends on the processes that alter, remineralize, and preserve particulate organic carbon (POC) during transit to the deep ocean. Here, we present data collected from the Great Calcite Belt, a calcite-rich band across the Southern Ocean surface, to compare the transformation of POC in the euphotic and mesopelagic zones of the water column. The [superscript 234]Th-derived export fluxes and size-fractionated concentrations of POC, particulate inorganic carbon (PIC), and biogenic silica (BSi) were measured from the upper 1000 m of 27 stations across the Atlantic and Indian sectors of the Great Calcite Belt. POC export out of the euphotic zone was correlated with BSi export. PIC export was not, but did correlate positively with POC flux transfer efficiency. Moreover, regions of high BSi concentrations, which corresponded to regions with proportionally larger particles, exhibited higher attenuation of > 51 μm POC concentrations in the mesopelagic zone. The interplay among POC size partitioning, mineral composition, and POC attenuation suggests a more fundamental driver of POC transfer through both depth regimes in the Great Calcite Belt. In particular, we argue that diatom-rich communities produce large and labile POC aggregates, which not only generate high export fluxes but also drive more remineralization in the mesopelagic zone. We observe the opposite in communities with smaller calcifying phytoplankton, such as coccolithophores. We hypothesize that these differences are influenced by inherent differences in the lability of POC exported by different phytoplankton communities. 2015-08-19T18:28:33Z 2015-08-19T18:28:33Z 2015-07 2015-05 Article http://purl.org/eprint/type/JournalArticle 1726-4189 http://hdl.handle.net/1721.1/98111 Rosengard, S. Z., P. J. Lam, W. M. Balch, M. E. Auro, S. Pike, D. Drapeau, and B. Bowler. “Carbon Export and Transfer to Depth Across the Southern Ocean Great Calcite Belt.” Biogeosciences 12, no. 13 (2015): 3953–3971. https://orcid.org/0000-0001-9127-9884 en_US http://dx.doi.org/10.5194/bg-12-3953-2015 Biogeosciences Creative Commons Attribution http://creativecommons.org/licenses/by/3.0/ application/pdf Copernicus GmbH Copernicus Publications |
| spellingShingle | Lam, P. J. Balch, W. M. Auro, M. E. Pike, S. Drapeau, D. Bowler, B. Rosengard, Sarah Zhou Carbon export and transfer to depth across the Southern Ocean Great Calcite Belt |
| title | Carbon export and transfer to depth across the Southern Ocean Great Calcite Belt |
| title_full | Carbon export and transfer to depth across the Southern Ocean Great Calcite Belt |
| title_fullStr | Carbon export and transfer to depth across the Southern Ocean Great Calcite Belt |
| title_full_unstemmed | Carbon export and transfer to depth across the Southern Ocean Great Calcite Belt |
| title_short | Carbon export and transfer to depth across the Southern Ocean Great Calcite Belt |
| title_sort | carbon export and transfer to depth across the southern ocean great calcite belt |
| url | http://hdl.handle.net/1721.1/98111 https://orcid.org/0000-0001-9127-9884 |
| work_keys_str_mv | AT lampj carbonexportandtransfertodepthacrossthesouthernoceangreatcalcitebelt AT balchwm carbonexportandtransfertodepthacrossthesouthernoceangreatcalcitebelt AT aurome carbonexportandtransfertodepthacrossthesouthernoceangreatcalcitebelt AT pikes carbonexportandtransfertodepthacrossthesouthernoceangreatcalcitebelt AT drapeaud carbonexportandtransfertodepthacrossthesouthernoceangreatcalcitebelt AT bowlerb carbonexportandtransfertodepthacrossthesouthernoceangreatcalcitebelt AT rosengardsarahzhou carbonexportandtransfertodepthacrossthesouthernoceangreatcalcitebelt |