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

 


Stubble Burning In Canterbury Damages The Soil

Stubble Burning In Canterbury Damages The Soil

March 11, 2014

An international soil scientist is critical of the practice of burning residue which often occurs on farms after harvest.

Dr John Baker visited Mid Canterbury recently and witnessed a large scale burn off near Chertsey polluting the atmosphere. While it may not have harmed the soil at the time, it certainly will destroy much of the opportunity to improve the soil health in the future he says.

He says burning residues simply removes most of the carbon present in the residues of the previous crop by converting it to CO2 by combustion.

“The main way to maximise arable soil quality and health is to increase its carbon content, not burn it off. Increasing carbon and soil microbial activity in turn builds soil structure and is one of the strongest indicators of soil health or quality,” Dr Baker says.

Dr Baker, who has a MAgrSc in soil science and Ph.D in agricultural engineering from Massey University, has reacted with caution to a recent Foundation for Arable Research (FAR) report that “stubble burning is valued by some farmers as a rapid, economic and relatively benign way of dealing with crop residue.”

“Burning is bad for the soil as it destroys all the available new organic matter which is used to build humus. Residue feeds worms and builds soil organic matter,” he comments.

Dr Baker concedes that occasional burning can help with weed and pest control but is critical that FAR sees burning as creating a basis for a more productive and profitable farming system. Most of the evidence is to the contrary he points out.

“Retaining residue and seeding through it with low-disturbance no-tillage is a far superior method than intensive tillage (ploughing) with or without burning. Any form of tillage is also detrimental to soil quality,” he says.

Dr Baker, who was a finalist for the World Food Prize in 2013, cannot over-emphasise the importance of good quality soil. He says the single greatest challenge facing the world today is feeding the extra 50 percent population by the year 2050.

“Only four percent of the world’s surface has arable soil and that’s not likely to increase so we have to farm it more sustainably which we simply haven’t been doing,” he says.

“To farm it sustainably and increase crop yields requires preserving and maintaining soil quality and organic matter. I don’t see that happening on properties where stubble burning is a regular occurrence.”

Dr Baker has been researching no-tillage for 40 years and invented and manufactured a low-disturbance no-tillage drill that penetrates through crop residue on top of the ground and sows seeds and fertiliser directly into unploughed ground.

“No-tillage is the equivalent of keyhole surgery as opposed to ploughing which is invasive surgery,” he says.

“Good no-tillage causes minimal disturbance to the soil, traps the humidity, preserves micro-organisms and soil life, largely prevents carbon from escaping into the atmosphere and significantly improves crop yields. One kilogram of humus in the soil holds as much water as nine kilograms of clay. So it’s a no-brainer really.”

“It will simply become the key to feeding our world in the years to come.”

Ends

© Scoop Media

 
 
 
 
 
Business Headlines | Sci-Tech Headlines

 

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:

Commerce: Supermarket Inquiry Finds No Breaches By Countdown

The Commerce Commission inquiry into anti-competitive behaviour by Countdown supermarkets, alleged by former Labour Party MP Shane Jones, has found nothing to warrant prosecution, although it warns supermarkets to take care in the way they communicate... More>>

ALSO:

Crown Accounts: English Flags ‘Challenge’ To Budget Surplus

Finance Minister Bill English is warning next month’s half yearly fiscal and economic update from the Treasury may not forecast a budget surplus, saying that returning the government’s accounts to surplus in 2015 will be “a challenge”, given the decline in commodity prices and weak global inflation. More>>

ALSO:

March 2015: Netflix To Launch In Australia And New Zealand

World’s Leading Internet Television Network to Offer Original Series, Movies, Documentaries, Stand-Up Comedy Specials and TV Shows for Low Monthly Price More>>

ALSO:

Price Of Cheese (Is Up): Dairy Product Prices Fall To Five-Year Low

Dairy product prices fell in the latest GlobalDairyTrade auction to the lowest level in more than five years, led by declines in rennet casein and skim milk powder. More>>

ALSO:

Gordon Campbell: On The Australians Scoring Trade Points Against Us With The Chinese

It hasn’t been a great year for Trade Minister Tim Groser... To top it off, Australia has just signed a FTA with China that has far better provisions on dairy exports than what New Zealand currently enjoys in our own FTA with China. More>>

ALSO:

Iwi & Local Consultation: Oil And Gas Block Offer 2015 Begins

Energy and Resources Minister Simon Bridges today announced the start of the Block Offer 2015 process for awarding oil and gas exploration permits. More>>

Industrial Action: Stats NZ Throwing Public Money Away Duplicating Data

The Public Service Association (PSA) says Statistics NZ are throwing money away by collecting the same data twice for official statistics such as the Consumer Price Index... As part of the ongoing industrial action, field interviewers who are PSA members are continuing to collect data, but are not sending it through to Statistics NZ. More>>

ALSO:

Other Stats:

Space: Rosetta's 'Philae' Makes Historic First Landing On A Comet

After more than a decade traveling through space, a robotic lander built by the European Space Agency has made the first-ever soft landing of a spacecraft on a comet. More>>

ALSO:

Get More From Scoop

 
 
Standards New Zealand

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