Crop breeding could 'slash CO2 levels'

August 3, 2011, University of Manchester

Writing in the journal Annals of Botany, Professor Douglas Kell argues that developing crops that produce roots more deeply in the ground could harvest more carbon from the air, and make crops more drought resistant, while dramatically reducing carbon levels.

In principle, any could be treated in this way, giving more productive yields while also being better for the environment.

Although the amount of carbon presently sequestered in the soil in the natural environment and using existing crops and grasses has been known for some time, Professor Kell's new analysis is the first to reveal the benefits to the environment that might come from breeding novel crops with root traits designed to enhance carbon sequestration.

Professor Kell, Professor of Bioanalytical Science at the University as well as Chief Executive of the and Biological Sciences Research Council (BBSRC), has also devised a carbon calculator that can show the potential benefits of crops that burrow more deeply in the ground.

With this, he has calculated that – depending on the time it takes them to break down –breeding crops that could cover present cropland areas but that had roots a metre deeper in the soil could double the amount of carbon captured from the environment. This could be a significant weapon in the fight against climate change.

The soil represents a reservoir that contains at least twice as much carbon as does the atmosphere, yet mainly just the above-ground plant biomass is harvested in agriculture, and plant photosynthesis represents the effective origin of the overwhelming bulk of soil carbon.

Breeding crop plants with deeper and bushy root ecosystems could simultaneously improve both the soil structure and its steady-state carbon, water and nutrient retention, as well as sustainable plant yields.

Professor Kell argues that widespread changes in agricultural practice are needed, in an environment in which edible crop yields also need to increase substantially and sustainably, and where transport fuels and organic chemicals will need to come from modern (rather than fossil) photosynthesis.

It is known that massive CO2 reductions in the atmosphere over geological time have happened because of the rise of deep-rooted trees and flowering plants.

Most cultivated agricultural crops have root depths that do not extend much beyond one metre. Doubling this, Professor Kell argues, would dramatically reduce CO2 levels.

Existing studies, which have doubted the benefits of deep roots in carbon sequestration, do not make measurements much below a metre, and the kinds of root depths proposed by Professor Kell would more than double that.

He said: "This doubling of root biomass from a nominal 1m to a nominal 2m is really the key issue, together with the longevity of the roots and they secrete and sequester below-ground.

"What matters is not so much what is happening now as what might be achieved with suitable breeding of plants with deep and reasonably long-lived roots. Many such plants exist, but have not been bred for agriculture.

"In addition to the simple that this breeding could imply – possibly double that of common annual grain crops – such plants seem to mobilise and retain nutrients and water very effectively over extended periods, thus providing resistance to drought, flooding and other challenges we shall face from climate change.

"While there is a way to go before such crops might have, for example, the grain yields of present day cereals, their breeding and deployment seems a very promising avenue for sustainable agriculture."

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2.6 / 5 (5) Aug 03, 2011
How many times do I have to say it, AGW is not about warming, carbon, or finding solutions. It's about politics, money, and ideology. No environmentalist organization worth its salt is going to advocate any sort of technological quick fix. Nothing short of public transportation, veganism, and de-industrialization will satisfy. Forget the nuclear power, solar power, wind power. Forget carbon sequestration, particulate boosting, chemical mitigation, whatever. It's all about changing the way we think about living. Baaaaahhh. Now you are a sheep drinking the green koolaid. Koombayah, lets hold hands and focus our positive energy on peace. Worked fine for Tibet. did it?
1 / 5 (1) Aug 03, 2011
Plants might well be able to grow deeper root systems with only minor biological changes but do not since they have been selected not to by the competition to develop quicker than their rivals. For crops such competition does not apply.
4 / 5 (1) Aug 03, 2011
When I brought plant breeding up to the Presidential Council on Climate Change, I got the response "We'll look into that".

Climate change is real. So is our ability to adapt.

The truth of the matter is, we are starving most of our worlds plants of precious C02, with current averages being under 100ppm for most of the world. During Pangean times, levels topped 2100ppm, and the Earth had 3-4 times more species of life.

5 / 5 (1) Aug 04, 2011
When I brought plant breeding up to the Presidential Council on Climate Change, I got the response "We'll look into that".

God forbid someone finds a solution. What would we do without a climate crisis?
1 / 5 (1) Aug 04, 2011
Article: "This could be a significant weapon in the fight against climate change." What is really required is a weapon against the politics, money and ideology promoting the climate change hoax!
The correlation of temperature changes to solar intensity from 1895 to 2007 is 0.85; to ocean oscillations from 1895 to 2007, 0.57; to CO2 from 1897 to 2007, 0.43, but to CO2 from 1987 to 2007, only 0.02. Since peaking in 1998, temperatures have declined while CO2 has increased, conflicting with all climate models.

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