Variable light illuminates the distribution of picophytoplankton

Dec 19, 2007

Tiny photosynthetic plankton less than a millionth of a millimeter in diameter numerically dominate marine phytoplankton. Their photosynthesis uses light to drive carbon dioxide uptake, fueling the marine food web over vast areas of the oceans. A new study published in this week’s PLoS ONE by post-doctoral researcher Dr Christophe Six and a team of scientists from MountAllison University, Sackville, New Brunswick, Canada, illuminates how the environment regulates the distributions of these ecologically important species.

Dr Doug Campbell, Canadian Research Chair in Environmental Processes and co-author explains, "Phytoplankton are entrained in the water column and are thus subject to rapid changes in light as they mix through the upper layer of the ocean."

Dr Christophe Six adds, “Phytoplankton need light for photosynthesis and survival, but surprisingly this light also inactivates a key component of the photosynthetic apparatus, photosystem II. This Photoinactivation of photosystem II decreases photosynthesis and can even kill cells, unless they can counteract the damage through repair, which requires nutrients.”

“We found the picophytoplankton species isolated from different regions of the ocean have different abilities for this repair, and therefore have different abilities to tolerate increases in light. Their repair capacities are consistent with the different light and nutrient regimes in their local environments; species from deep ocean regions with stable light and low nutrients have very limited repair capacity, but species from coastal regions with more variable light and higher nutrients are more able to cope with variable light through rapid repair.”

This result indicates that picophytoplankton species’ tolerance of exposures to high light can help to explain how these organisms are distributed throughout the ocean. The group measures the rates of photoinactivation and the rates of the counteracting repair in a wide variety of phytoplankton species, and next plans to contribute to ocean models to predict phytoplankton carbon cycling in response to future climate change.

Source: Public Library of Science

Explore further: Diabetes drug found in freshwater is a potential cause of intersex fish

Related Stories

Space Station sensor to capture 'striking' lightning data

Mar 04, 2014

Keeping a spare on hand simply makes sense. Just as drivers keep spare tires on hand to replace a flat or blowout, NASA routinely maintains "spares," too. These flight hardware backups allow NASA to seamlessly ...

Recommended for you

Single cells seen in unprecedented detail

49 minutes ago

Researchers have developed a large-scale sequencing technique called Genome and Transcriptome Sequencing (G&T-seq) that reveals, simultaneously, the unique genome sequence of a single cell and the activity ...

Conifer study illustrates twists of evolution

56 minutes ago

A new study offers not only a sweeping analysis of how pollination has evolved among conifers but also an illustration of how evolution—far from being a straight-ahead march of progress—sometimes allows ...

Bumblebees use nicotine to fight off parasites

1 hour ago

Researchers from Queen Mary University of London (QMUL) and Royal Holloway, University of London (RHUL), gave bumblebees the option to choose between a sugar solution with nicotine in it and one without. ...

New 3-D method improves the study of proteins

2 hours ago

Researchers have developed a new computational method called AGGRESCAN3D which will allow studying the 3D structure of folded globular proteins and substantially improve the prediction of any propensity for ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

out7x
1 / 5 (1) Dec 20, 2007
This must be the smallest living cell. Pico sized must be smaller than the "martian microbes" in ALH84001.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.