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The recently-withdrawn chemical had been spread on many New Zealand paddocks to block high rates of microbial nitrification thus reducing greenhouse gas emissions and nitrate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

 

Nurofen Promotion: Reckitt Benckiser To Plead Guilty To Misleading Ads

Reckitt Benckiser (New Zealand) intends to plead guilty to charges of misleading consumers over the way it promoted a range of Nurofen products, the Commerce Commission says. More>>

ALSO:

Half A Billion Accounts: Yahoo Confirms Huge Data Breach

The account information may have included names, email addresses, telephone numbers, dates of birth, hashed passwords (the vast majority with bcrypt) and, in some cases, encrypted or unencrypted security questions and answers. More>>

Rural Branches: Westpac To Close 19 Branches, ANZ Looks At 7

Westpac confirms it will close nineteen branches across the country; ANZ closes its Ngaruawahia branch and is consulting on plans to close six more branches; The bank workers union says many of its members are nervous about their futures and asking ... More>>

Interest Rates: RBNZ's Wheeler Keeps OCR At 2%

Reserve Bank governor Graeme Wheeler kept the official cash rate at 2 percent and said more easing will be needed to get inflation back within the target band. More>>

ALSO:

Half Full: Fonterra Raises Forecast Payout As Global Supply Shrinks

Fonterra Cooperative Group, the dairy processor which will announce annual earnings tomorrow, hiked its forecast payout to farmers by 50 cents per kilogram of milk solids as global supply continues to decline, helping prop up dairy prices. More>>

ALSO:

Results:

Meat Trade: Silver Fern Farms Gets Green Light For Shanghai Maling Deal

The government has given the green light for China's Shanghai Maling Aquarius to acquire half of Silver Fern Farms, New Zealand's biggest meat company, with ministers satisfied it will deliver "substantial and identifiable benefit". More>>

ALSO:

Get More From Scoop

 
 
 
 
 
 
 
 
 
Sci-Tech
Search Scoop  
 
 
Powered by Vodafone
NZ independent news