Haptophytes in polar waters
Abstract Haptophytes are abundant and important constituents of the plankton of polar waters. The colonial stage of Phaeocystis commonly dominates the phytoplankton of the marginal ice zone where it is a major source of particulate and dissolved organic carbon. The extent to which this species contr...
| Main Authors: | , |
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| Format: | Book Part |
| Language: | unknown |
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Oxford University PressOxford
1994
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| Online Access: | http://dx.doi.org/10.1093/oso/9780198577720.003.0011 https://academic.oup.com/book/chapter-pdf/52372794/isbn-9780198577720-book-part-11.pdf |
| Summary: | Abstract Haptophytes are abundant and important constituents of the plankton of polar waters. The colonial stage of Phaeocystis commonly dominates the phytoplankton of the marginal ice zone where it is a major source of particulate and dissolved organic carbon. The extent to which this species contributes to carbon flux to the deep sea is equivocal, but recent evidence indicates that, despite heavy sedimentation, much is utilized by microbial activity and grazing in the upper aphotic zone. Phaeocystis is also a major source of the precursor of dimethyl sulfide, which in air is rapidly oxidized to a number of products including sulfate. It has been proposed that sulfate particles act as cloud condensation nuclei thereby influencing global albedo and therefore climate. Lightly calcified coccolithophorids are a characteristic, but not endemic, element of polar nanoplankton. Originally considered to be autotrophic, it has recently been found that they are heterotrophic. The mixotrophic genus Chrysochromulina occurs associated with the sea ice and in the water column. Finding scales of these organisms in gut contents of Antarctic krill, Euphausia superba, collected from under the ice during winter, has prompted speculation on the importance of mixotrophy in light limited polar waters. |
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