Featured Research

from universities, journals, and other organizations

Southern Ocean sampling reveals travels of marine microbes

Date:
September 18, 2013
Source:
University of New South Wales
Summary:
By collecting water samples up to six kilometers below the surface of the Southern Ocean, researchers have shown for the first time the impact of ocean currents on the distribution and abundance of marine micro-organisms. Twenty-five samples were collected across a 3,000 kilometer stretch of ocean and genetic sequencing of the microbial DNA in each sample was carried out. The research shows that microbial communities that are connected by ocean currents are more similar to each other.

This image shows the Australia icebreaker, RSV Aurora Australis, from which samples of water in the Southern Ocean were taken at depths of up to 6 kilometers to study the marine microbes living there.
Credit: UNSW

By collecting water samples up to six kilometres below the surface of the Southern Ocean, UNSW researchers have shown for the first time the impact of ocean currents on the distribution and abundance of marine micro-organisms.

The sampling was the deepest ever undertaken from the Australian icebreaker, RSV Aurora Australis.

Microbes are so tiny they are invisible to the naked eye, but they are vital to sustaining life on earth, producing most of the oxygen we breathe, soaking up carbon dioxide from the atmosphere and recycling nutrients.

"Microbes form the bulk of the biomass in oceans. All the fish, dolphins, whales, sponges and other creatures account for less than 5 per cent of the biomass," says Professor Rick Cavicchioli, of the UNSW School of Biotechnology and Biomolecular Sciences, and leader of the team.

"Microbes perform roles that nothing else can carry out. And if one critical group of microbes was destroyed, life on the planet would cease to exist."

The influence of environmental conditions on the make-up of microbial communities in different regions of the ocean has been studied, as has the role of physical barriers in preventing their dispersal.

"Collecting samples in the Southern Ocean was an enormous challenge. But it has meant we were able to carry out the first study showing how physical transport in the ocean on currents can also shape microbial communities," says Professor Cavicchioli.

The results are published in the journal Nature Communications.

Twenty five samples were collected across a 3000 kilometre stretch of ocean between Antarctica and the southern tip of Western Australia. Sampling depths were determined by temperature, salinity and dissolved oxygen measurements, to ensure microbes were collected from all the distinct water masses of the Southern Ocean.

These water masses include the circumpolar deep water, which flows toward the south pole from the Indian, Pacific Ocean and Atlantic oceans; the surface water near the Antarctic coastline; and the cold, dense Antarctic bottom water, which flows north, away from the pole, at more than 4 kilometres depth.

Genetic sequencing of the microbial DNA in each sample was carried out to characterise the microbial communities in different water-masses. The research shows that communities that are connected by ocean currents are more similar to each other.

"So a microbial community could be very different to one only a few hundred metres away, but closely related to one that is thousands of kilometres away because they are connected by a current," says Professor Cavicchioli.

"Researchers need to take this into account when they are studying these important micro-organisms."

The results were tested by Dr Erik Van Sebille, of the UNSW Climate Change Research Centre, who used a computer model of the Southern Ocean to carry out a 100-year long simulation of how particles would move as a result of ocean circulation.

Dr David Wilkins, who carried out the research for his PhD under Professor Cavicchioli's supervision, is first author on the paper. The team also included UNSW's Dr Federico Lauro and Dr Stephen Rintoul, of CSIRO.


Story Source:

The above story is based on materials provided by University of New South Wales. Note: Materials may be edited for content and length.


Journal Reference:

  1. David Wilkins, Erik van Sebille, Stephen R. Rintoul, Federico M. Lauro, Ricardo Cavicchioli. Advection shapes Southern Ocean microbial assemblages independent of distance and environment effects. Nature Communications, 2013; 4 DOI: 10.1038/ncomms3457

Cite This Page:

University of New South Wales. "Southern Ocean sampling reveals travels of marine microbes." ScienceDaily. ScienceDaily, 18 September 2013. <www.sciencedaily.com/releases/2013/09/130918101856.htm>.
University of New South Wales. (2013, September 18). Southern Ocean sampling reveals travels of marine microbes. ScienceDaily. Retrieved September 1, 2014 from www.sciencedaily.com/releases/2013/09/130918101856.htm
University of New South Wales. "Southern Ocean sampling reveals travels of marine microbes." ScienceDaily. www.sciencedaily.com/releases/2013/09/130918101856.htm (accessed September 1, 2014).

Share This




More Earth & Climate News

Monday, September 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Iceland Lowers Aviation Alert on Volcano

Iceland Lowers Aviation Alert on Volcano

AFP (Sep. 1, 2014) — Iceland has lowered its aviation alert on its largest volcano after a fresh eruption on a nearby lava field prompted authorities to enforce a flight ban for several hours. Duration: 01:07 Video provided by AFP
Powered by NewsLook.com
Lightning Hurts 3 on NYC Beach

Lightning Hurts 3 on NYC Beach

AP (Sep. 1, 2014) — A lightning strike injured three people on a New York City beach on Sunday. The storms also delayed flights and interrupted play at the US Open tennis tournament. (Sept. 1) Video provided by AP
Powered by NewsLook.com
Thailand Totters Towards Waste Crisis

Thailand Totters Towards Waste Crisis

AFP (Sep. 1, 2014) — Fears are mounting in Bangkok that poor planning and lax law enforcement are tipping Thailand towards a waste crisis. Duration: 01:21 Video provided by AFP
Powered by NewsLook.com
Melting Ice Shelves Drive Rapid Antarctic Sea Level Rise

Melting Ice Shelves Drive Rapid Antarctic Sea Level Rise

Newsy (Sep. 1, 2014) — A study of almost 20 years' worth of satellite images shows Antarctic sea levels are on the rise as ice shelves continue to melt. Video provided by Newsy
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:
from the past week

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