While the main focus of my research interests is in the calcifying coccolithophores, the samples that we have obtained in the cold polar waters have been dominated by diatoms and dinoflagellates.
Phytoplankton @ Colin Brownlee
The picture shows a few examples of live diatoms and other phytoplankton in fresh samples from polar waters. A: A single cell of a chain-forming species of Chaetoceros; B: Left image shows a very large diatom( Rhizosolenia spp.) with a smaller unidentified diatom( top), and two dinoflagellates. The image of chlorophyll fluorescence shows that these cells are all photosynthetic, apart from the dinoflagellate at the bottom left which has no chlorophyll( heterotrophic). C: Another very large diatom( Coscinodiscus spp.) with a very small unidentified diatom( bottom right); D: A population of small diatoms. Interestingly, different sampling stations give different proportions of very large and very small diatoms; E: A silicoflagellate( Dichtyocha speculum). Middle picture: A minke whale. Note the pictures are not all at the same scale!
Taking pictures of phytoplankton while we are sampling gives a feeling of reassurance that there is actually something alive in this freezing cold water. Microscopy at sea, however does come with some problems. Firstly, a moving, vibrating ship is not an ideal platform for looking at creatures a few microns in size. However, modern fast, sensitive cameras have made this far less of a problem than it used to be. Secondly, staring down a microscope on a lurching rolling ship can seriously affect your digestion. Fortunately we all have our sea legs at this stage of the cruise. Thirdly, there is a real danger of becoming too immersed in
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