Featured Research

from universities, journals, and other organizations

Bioluminescence reveals deep-water motion in the Mediterranean

Date:
July 11, 2013
Source:
Centre national de la recherche scientifique (CNRS)
Summary:
In 2009 and 2010, the underwater neutrino telescope ANTARES detected an unusual phenomenon: the bioluminescence of deep-sea organisms suddenly increased, revealing an unexpected connection between biological activity -- bioluminescence -- and the motion of water masses in the deep ocean. Convective motion in the Gulf of Lion provides deep waters with oxygen and nutrients that boost biological activity.

The North-West Mediterranean Sea is the best region to study dense water formation.
Credit: Image courtesy of Universidad de Barcelona

In 2009 and 2010, the underwater neutrino telescope ANTARES detected an unusual phenomenon: the bioluminescence of deep-sea organisms suddenly increased, revealing an unexpected connection between biological activity -- bioluminescence -- and the motion of water masses in the deep ocean. Convective motion in the Gulf of Lion provides deep waters with oxygen and nutrients that boost biological activity.

Published July 10 in PLoS ONE, the work was carried out by a team coordinated by CNRS researchers from the Institut Méditerranéen d'Océanographie (CNRS / IRD / Aix-Marseille Université / Université du Sud Toulon-Var) and the Centre de Physique des Particules de Marseille (CNRS / Aix-Marseille Université).

Located off the coast of Toulon, the purpose of the ANTARES telescope is to detect very high energy cosmic neutrinos (1). These particles rarely interact with matter. However, when one of them strikes a water molecule, it can produce a charged particle called a muon, which emits photons as it moves. This is the radiation that is detected by the 900 ANTARES photomultipliers at a depth of 2,400 meters.

The deep sea is not as dark as might be supposed: 90% of deep-sea organisms are able to emit light, which plays a role in many ecological interactions such as prey attraction or reproduction-related behavior. Deep-sea bacteria, whether free, in symbiosis with animals or attached to suspended particles, are able to emit light continuously and are adapted to their environment, as shown by Christian Tamburini and colleagues in another article published last June (2).

Such bioluminescence did not adversely affect the ANTARES mission. However, two episodes between March and July in 2009 and 2010 literally dazzled the telescope. The background light intensity measured by the detector, which is usually in the range 40 to 100 kHz, suddenly soared to 9 000 kHz. This peak in bioluminescence coincided with an increase in water temperature and salinity. This enabled the researchers to establish a link between bioluminescence and convective motion in the Gulf of Lion.

During especially cold, dry winters, the temperature of surface waters in the Gulf of Lion falls, while their salinity increases due to evaporation. As a result, these water masses become denser than those underlying them, and they sink. This motion, known as convection, is a well-known phenomenon. These surface waters are rich in oxygen and nutrients. When they sink, they provide deep waters with resources that boost biological activity. It is this bloom of biological activity that ANTARES unexpectedly detected.

The researchers believe that measuring bioluminescence could become the best way of continuously monitoring biological activity in the deep sea. It would shed light on the impact of the motion of water masses and ocean circulation on living organisms. This is all the more important as phenomena such as deep water convection are likely to decline significantly over the coming century due to global warming. This decline will have a major impact on deep-sea ecosystems, which will be deprived of this input of nutrients and oxygen. The researchers now intend to determine the as-yet-unidentified light-emitting organisms detected by ANTARES, and develop instrumentation to measure bioluminescence both continuously and autonomously.


Story Source:

The above story is based on materials provided by Centre national de la recherche scientifique (CNRS). Note: Materials may be edited for content and length.


Journal Reference:

  1. Christian Tamburini et al. Deep-Sea Bioluminescence Blooms after Dense Water Formation at the Ocean Surface. PLoS ONE, 2013; 8 (7): e67523 DOI: 10.1371/journal.pone.0067523

Cite This Page:

Centre national de la recherche scientifique (CNRS). "Bioluminescence reveals deep-water motion in the Mediterranean." ScienceDaily. ScienceDaily, 11 July 2013. <www.sciencedaily.com/releases/2013/07/130711084514.htm>.
Centre national de la recherche scientifique (CNRS). (2013, July 11). Bioluminescence reveals deep-water motion in the Mediterranean. ScienceDaily. Retrieved October 21, 2014 from www.sciencedaily.com/releases/2013/07/130711084514.htm
Centre national de la recherche scientifique (CNRS). "Bioluminescence reveals deep-water motion in the Mediterranean." ScienceDaily. www.sciencedaily.com/releases/2013/07/130711084514.htm (accessed October 21, 2014).

Share This



More Plants & Animals News

Tuesday, October 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

'Cadaver Dog' Sniffs out Human Remains

'Cadaver Dog' Sniffs out Human Remains

AP (Oct. 21, 2014) — Where's a body buried? Buster's nose can often tell you. He's a cadaver dog, specially trained to find human remains and increasingly being used by law enforcement and accepted in courts. These dogs are helping solve even decades-old mysteries. (Oct. 21) Video provided by AP
Powered by NewsLook.com
White Lion Cubs Born in Belgrade Zoo

White Lion Cubs Born in Belgrade Zoo

AFP (Oct. 20, 2014) — Two white lion cubs, an extremely rare subspecies of the African lion, were recently born at Belgrade Zoo. They are being bottle fed by zoo keepers after they were rejected by their mother after birth. Duration: 00:42 Video provided by AFP
Powered by NewsLook.com
Traditional Farming Methods Gaining Ground in Mali

Traditional Farming Methods Gaining Ground in Mali

AFP (Oct. 20, 2014) — He is leading a one man agricultural revolution in Mali - Oumar Diatabe uses traditional farming methods to get the most out of his land and is teaching others across the country how to do the same. Duration: 01:44 Video provided by AFP
Powered by NewsLook.com
Goliath Spider Will Give You Nightmares

Goliath Spider Will Give You Nightmares

Buzz60 (Oct. 20, 2014) — An entomologist stumbled upon a South American Goliath Birdeater. With a name like that, you know it's a terrifying creepy crawler. Sean Dowling (@SeanDowlingTV) has the details. Video provided by Buzz60
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins