Video | Business Headlines | Internet | Science | Scientific Ethics | Technology | Search

 


Freshwater flows affect polar oceanic microbes

NIWA Media Release Scientists discover freshwater flows affect polar oceanic microbes


An international team of scientists has been studying bacteria that live in Arctic and Antarctica waters.

NIWA’s Marine Microbiologist, Els Maas says, “The polar regions often are described as being mirror images of one another so we were expecting the bacteria populations to be comparable”.

However, genetic sequencing has shown that 75 per cent of the bacteria found in the surface coastal waters are unique to either the Arctic or Antarctica. The differences are not nearly so marked in deeper waters and the scientists believe that freshwater from glaciers and streams to the Arctic and Antarctica appears to be responsible for the difference.

One of the most notable differences in environmental conditions between the two polar oceans is freshwater input. In the Antarctica, glacial meltwater accounts for most of the freshwater that flows into the systems. In contrast, the Arctic ocean receives much more freshwater from several large rivers with huge continental drainage basins, in addition to glacial meltwater.

Dr Maas says, “It’s important to study bacteria because we don’t understand much about their diversity, especially how they contribute to the food web. Bacteria are important in recycling nutrients and making these available to larger plants and animals.”

The scientists compared samples from coastal and open oceans, between winter and summer (2000-2008), to test whether or how environmental conditions and dispersal patterns shape communities in the polar oceans. Samples were processed using a DNA sequencing technique called pyrosequencing, involving more than 800,000 sequences from the 92 samples.

The New Zealand samples were collected as part of the New Zealand Government-funded IPY-CAML (International Polar Year Census of Antarctic Marine Life) research trip to the Ross Sea in 2008 on board NIWA’s research vessel Tangaroa. The NIWA samples were the southern-most samples analysed.

The collaborative research was the result of an international effort coordinated by Dr Alison Murray, Desert Research Institute, USA. It involved national polar research programs from six countries -Canada, France, New Zealand, Spain, Sweden and the United States. Support for the work also came from the Sloan Foundation's Census of Marine Life program and the International Census of Marine Microbes, which developed the approach and conducted the sequencing effort.


ENDS

© Scoop Media

 
 
 
 
 
Business Headlines | Sci-Tech Headlines

 

Must Sell 20 Petrol Stations: Z Cleared To Buy Caltex Assets

Z Energy is allowed to buy the Caltex and Challenge! petrol station chains but must sell 19 of its retail sites and one truck-stop, the Commerce Commission has ruled in a split decision that acknowledges possible retail price coordination between fuel retailers occurs in some regions. More>>

ALSO:

Huntly: Genesis Extends Life Of Coal-Fuelled Power Station To 2022

Genesis Energy will keep its two coal and gas-fired units at Huntly Power Station operating until 2022, having previously said they'd be closed by 2018, after wringing a high price from other electricity generators who wanted to keep them as back-up. More>>

ALSO:

Dammed If You Do: Ruataniwha Irrigation Scheme Hits Farmer Uptake Targets

Enough Hawke's Bay farmers have signed up for water from the proposed Ruataniwha Water Storage Scheme for it to go ahead as long as a cornerstone institutional capital investor can be found to back it, its regional council promoter announced. More>>

ALSO:

Reserve Bank: OCR Stays At 2.25%

Reserve Bank governor Graeme Wheeler kept the official cash rate at 2.25 percent, in a decision traders had said could go either way, while predicting inflation will pick up as the slump in oil prices washes out of the data and capacity pressures start to build in the economy. More>>

ALSO:

Export Values Down: NZ Posts Biggest Annual Trade Deficit In 7 Years

New Zealand has recorded its biggest annual trade deficit since April 2009, reflecting weaker prices of agricultural commodities such as dairy products, beef and lamb, and increased imports of vehicles and machinery. More>>

ALSO:

Currency Events: NZ's New $5 Note Wins International Banknote Award

New Zealand’s new Brighter Money $5 note has been named Banknote of the Year in a prestigious international competition. The $5 note was awarded the IBNS Banknote of the Year title at the International Bank Note Society’s annual meeting. More>>

ALSO:

Get More From Scoop

 
 
 
 
 
 
 
 
 
Sci-Tech
Search Scoop  
 
 
Powered by Vodafone
NZ independent news