AbstractThaliacea (Tunicata) are fragile pelagic organisms, switching between sexual and asexual reproduction during their life cycle, occasionally occurring in massive blooms. During these blooms they graze large amounts of phytoplankton and microzooplankton, subsequently providing an enhanced carbon flux into deeper layers by sinking of faeces and dead and moribund animals. Seasonal variations and spatial distributions off the northern Namibian coast were analysed for December 2009, September 2010 and February 2011. Three Doliolida and four Salpida taxa were detected with a decreasing diversity towards the coast. Generally, Thaliacea preferred the upper 200 m of the water column but were also found in the mesopelagic zone. The abundances accounted for <1% of the mesozooplankton in most samples, but blooms with up to 63% were detected at some stations during moderate upwelling conditions. Intense upwelling seems to hamper the development of Thaliacea. During bloom periods, the relative abundance of asexually bred blasto- or gonozooids was highest. First estimates for a salp bloom off Walvis Bay (~11.000 ind. m−2, 0–200 m) revealed that 25–100% of the daily primary production was consumed during the bloom. Stable isotope analyses suggest a higher trophic level for Thaliacea than for herbivorous copepods.
Journal of Plankton Research – Oxford University Press
Published: Mar 1, 2017
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 12 million articles from more than
10,000 peer-reviewed journals.
All for just $49/month
Read as many articles as you need. Full articles with original layout, charts and figures. Read online, from anywhere.
Keep up with your field with Personalized Recommendations and Follow Journals to get automatic updates.
It’s easy to organize your research with our built-in tools.
Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera