Tag Archives: Phytoplankton

Phytoplankton waiting game perhaps key to their success in ocean deserts

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File:Survival Technique.JPGIn survival situations people often talk about the rule of three. It is said that humans can only survive for 3 minutes without air, 3 hours without heat, 3 days without water and 3 weeks without food. Not wanting to be left out, it seems that some phytoplankton also obey a rule of 3 according to a new study: they can survive for 3 weeks without key nutrients such as nitrogen and phosphorus.

Continue reading Phytoplankton waiting game perhaps key to their success in ocean deserts

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Ocean Deserts: it’s a hard life in the tropics, but not if you’re small

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Subtropical gyres are an extreme environment that covers approximately 30 % of the planet’s surface

Think of an extreme environment where life survives in the ocean. What springs to mind? The mind boggling pressures and eerie quiet of the deep-sea perhaps? Maybe the icy environments at the poles? Possibly even an estuary, where organisms are flung from one salinity extreme to the other on a daily basis. There is another extreme environment though, one which few of you probably even considered, one that covers about 30% of the planet and is currently expanding under the influence of climate change: large swirling systems of rotating currents that occur in the centre of oceans known as subtropical gyres.  Continue reading Ocean Deserts: it’s a hard life in the tropics, but not if you’re small

Chalk talk: Coccolithophores

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If you read my previous post on the interesting article about coccolithophore species-specific growth responses to environmental change, you may have been left wanting to know more about coccolithophores in general.  I don’t blame you.  Coccolithophores are pretty awesome. Continue reading Chalk talk: Coccolithophores

Using the past to predict the future of coccolithophores

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Some of the most progressive and interesting science happens when experts from different fields come together to tackle the same problem. Recently a group of plankton ecologists teamed up with some palaeontologists to assess how climate change impacts the growth of specific species of coccolithophores, both in modern times and during  a period of warming 56 million years ago. They showed that two species of coccolithophore responded very differently to this event. Continue reading Using the past to predict the future of coccolithophores

5 reasons why dinoflagellates are friggin’ awesome:

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Dinoflagellates are large single-celled motile phytoplankton that are extremely widespread and abundant in the ocean. They are astonishing little creatures that – depending on the species – can produce potent neurotoxins, feast on organisms many times larger than themselves (whilst also photosynthesising), travel large distances in search of nutrients, hibernate for up to 100 years, and glow with terrific blue-coloured bioluminesence. So, without further ado, here are five reasons why dinoflagellates are friggin’ awesome: Continue reading 5 reasons why dinoflagellates are friggin’ awesome:

‘Twas the night before Christmas (phytoplankton edition)

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A reworked (some would  say ‘improved’) version of  Clement Clarke Moore’s classic Christmas poem:

christmas plankton‘Twas the night before Christmas, and all through the ‘photic zone,
Few creatures were stirring, most plankton were all alone;
The water was mixed, with nutrients galore,
Critters hoping come spring, temperatures would soar. Continue reading ‘Twas the night before Christmas (phytoplankton edition)

Calcifying plankton and climate change

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Most of you reading this will be very familiar with the story of how ocean acidification is likely to impact marine calcifying organisms: increased carbon dioxide in the atmosphere is decreasing the pH of the oceans and is proposed to eventually lead to the dissolution of the shells of organisms made from calcium carbonate. It is difficult to work out in the lab, however, exactly what the impact of ocean acidification will be on marine calcifiers, as time pressures favour experiments that only assess short-term acclimation responses of organisms to ocean acidification (rather than long-term potential adaptations). Even when long term experiments have been carried out, they have only looked at the impact of pH change alone (see here), ignoring other relevent variables such as temperature. Continue reading Calcifying plankton and climate change

A guide to iron fertilisation of the ocean

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Image 1: A satellite image of the supposed iron-induced phytoplankton bloom. It seems to attribute all elevated chlorophyll concentrations in the region to the experiment. Chlorophyll is naturally patchy in its distribution, so this image is less than useless (especially as they didn’t even provide satellite images from before the dump!).

It was revealed this week that Russ George, a controversial American Businessman (Deep-Sea News ran a good piece this week covering his chequered history), dumped around 100 tonnes of “iron-rich dirt-like material” off the west coast of Canada in July in order to “gather data targeting all the possible fears that have been raised” about ocean fertilization – an act that is in violation of two international moratoria designed to prevent material from being dumped in the ocean. Judging from the poor quality of news coverage on the issue, which tended to include the deceptive image shown above (Image 1), there are a lot of misconceptions about iron fertilisation of the ocean. Here is the official Words in mOcean idiot’s guide to make you instantly more knowledgeable on this subject. Continue reading A guide to iron fertilisation of the ocean

Phytoplankton to the rescue: the promise offered by algal biofuels

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President Obama’s administration announced recently that as much as $14 million would be set aside to support the development of biofuels from algae. He was promptly mocked by some sections of the the US media and many of the Republican candidates. Serial ditcher of terminally ill wives, Newt Gingrich, proposed making T-shirts with the slogans, “You have Newt: Drill here, Drill Now, Pay Less. You have Obama: Have Algae, Pay More, Be Weird.” Continue reading Phytoplankton to the rescue: the promise offered by algal biofuels

Marine nitrogen fixation: the players

This is the second of two articles written by Elizabeth Sargent on the marine nitrogen cycle; the first article covered some of the basics and can be found here

A trichodesmium 'puff'. Oh, and watch out for this image in the April version of Scientific American

There are three main groups of nitrogen fixing organisms in the ocean: filamentous, heterocystous, and unicellular diazotrophs. The unicells are relatively new to the research scene (discovered in 1998), and are difficult to image due to their size, distribution, and our lack of knowledge about their lifestyle. I have some epifluorescent microscope images of unicellular diazotrophs, but you can get a good idea of what that looks like by picturing the night sky; it’s a whole lot of darkness and some tiny yellow dots. Continue reading Marine nitrogen fixation: the players