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

 


DCD may have unintended effects on aquatic environment


DCD may have unintended effects on aquatic environment: Otago research

University of Otago researchers have discovered that run-off of the agrichemical DCD may adversely affect some aquatic eco-systems by disrupting natural processes.

The recently-withdrawn chemical had been spread on many New Zealand paddocks to block high rates of microbial nitrification thus reducing greenhouse gas emissions and nitrate leaching into waters.

Findings from the Otago study, which is the first to investigate ecological impacts of DCD residues in aquatic eco-systems, are published this month in the international Journal of Agriculture, Ecosystems and Environment.

The study, led by Department of Zoology researcher Dr Marc Schallenberg, detected DCD residues in streams in Otago’s lower Taieri Plain in concentrations that cause natural nitrogen transformation processes to be disrupted in aquatic ecosystems.

Dr Schallenberg conducted laboratory experiments showing that in a wetland system, the presence of DCD inhibits the processes of nitrification and denitrification, two natural processes that help to purify and detoxify waters of ammonium by converting it to nitrate and inert nitrogen gas, respectively.

“While DCD’s inhibition of nitrification on land is desirable as it reduces the amount of nitrate entering streams, its similar inhibitory effects within aquatic environments is undesirable, as this could lead to ammonia toxicity in fish and other species, or increased incidences of algal blooms.”

Dr Schallenberg says research on downstream impacts of DCD should contribute to a more complete cost-benefit analysis of DCD use, should the DCD withdrawal by Fonterra be reversed in the future.

© Scoop Media

 
 
 
 
 
Business Headlines | Sci-Tech Headlines

 

Balance Of Trade: NZ Posts Trade Deficit In October On Falling Dairy Exports

New Zealand’s posted its largest monthly trade deficit for October in six years, while narrowing the shortfall from September, led by a fall in dairy exports to China while all main imports into the country rose. More>>

ALSO:

Gigatown Winner: Plenty Of Positives For Dunedin

Although the city has taken the Gigatown title, along with new ultrafast 1Gbps broadband and funding for $700,000 worth of UFB-related initiatives across the community, Mr Cull says Dunedin has gained so much more through its involvement. More>>

ALSO:

R18: The Warehouse Group Praised For Removing Games

The decision by New Zealand’s largest retailer The Warehouse Group (TW Group), to withdraw stocks of the latest version of Grand Theft Auto V (GTA V) and other R18 games, has been praised by advocacy group Stop Demand Foundation. More>>

ALSO:

Air NZ Wine Awards: Victory For Villa Maria As Pinot Noir Thrills

It was a night to remember as Villa Maria Estate picked up one of the highest accolades of the evening, the O-I New Zealand Reserve Wine of the Show Trophy, at the 28th Air New Zealand Wine Awards. The Villa Maria Single Vineyard Southern Clays Marlborough ... More>>

ALSO:

Future Brighter Money: RBNZ Releases New Bank Note Designs

New Zealand’s banknotes are getting brighter and better, with the Reserve Bank today unveiling more vibrant and secure banknote designs which will progressively enter circulation later next year. More>>

ALSO:

Get More From Scoop

 
 
Standards New Zealand

Standards New Zealand
 
 
 
 
 
 
 
 
Sci-Tech
Search Scoop  
 
 
Powered by Vodafone
NZ independent news