The world is on course to produce
more wheat this year than ever before. Yet as supply rises to
meet demand, so do the carbon emissions from growing and harvesting
Now a 25-year long field experiment in Canada
shows that growing wheat can actually take up more carbon than it
releases. Meeting demand for food doesn't have to mean more carbon
emissions, the study's lead scientist tells us.
Wheat is in demand
Wheat is the third most-grown cereal crop in the
world, after maize and rice. Demand
for major cereal crops such as wheat is expected to increase
by 70 percent by 2050.
In the UK, around two million hectares of land
are used to grow wheat, with the harvested crop worth around
billion. But wheat accounts for 30 per cent of
emissions from growing the crops we eat,
Fuel burned in tractors used to farm land
releases carbon dioxide, as does producing and using fertilisers.
These emissions typically outweigh the amount of carbon dioxide the
crops absorb as they grow.
Now a new study by Canadian researchers,
published in Nature
Communications, finds that with some changes to
farming practices, growing wheat can actually remove more carbon
dioxide from the atmosphere than it produces.
Little field on a prairie
The US and Canada are the third and fifth
largest producers of wheat in the world. Between them they
harvested around 90 million tons of wheat last year. Most of this
is grown in the 'wheat belt', a vast area of the North American
prairies that stretches across much of central US and Canada.