Desert 'carbon Farming' To Curb CO2

Desert 'carbon farming' to curb CO2

1 August 2013

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By Matt McGrath

Environment reporter, BBC News

Scientists say that planting big numbers of jatropha trees in desert locations might be an effective way of suppressing emissions of CO2.

Dubbed "carbon farming", scientists say the concept is economically competitive with modern carbon capture and storage jobs.

But critics state the concept might be have unpredicted, unfavorable impacts including increasing food costs.

The research has been released, external in the journal Earth System Dynamics.

Seeds of modification

Jatropha curcas is a plant that came from Central America and is extremely well adapted to harsh conditions including very dry deserts.

It is currently grown as a biofuel, external in some parts of the world due to the fact that its seeds can produce oil.

In this study, German researchers revealed that one hectare of jatropha could capture approximately 25 tonnes of co2 from the atmosphere every year. The researchers based their price quotes on trees currently growing in trial plots in Egypt and in the Negev desert.

"The results are overwhelming," stated Prof Klaus Becker, from the University of Hohenheim in Stuttgart.

"There was excellent growth, a great response from these plants. I feel there will be no issue trying it on a much larger scale, for instance ten thousand hectares in the start," he stated.

According to the scientists a plantation that would cover three percent of the Arabian desert would absorb all the CO2 produced by automobiles and trucks in Germany over a 20 year duration.

The researchers state that a crucial element of the strategy would be the schedule of desalination centers. This means that initially, any plantations would be confined to seaside areas.

They are intending to develop larger trials in desert areas of Oman or Qatar. Prof Becker states that unlike other plans that just offset the carbon that people produce, the planting of jatropha could be an excellent, short-term option to climate modification.

"I believe it is a good idea since we are actually drawing out carbon dioxide from the environment - and it is completely various in between extracting and avoiding."

According to the scientist's calculations the costs of suppressing co2 by means of the planting of trees would be between 42 and 63 euros per tonne. This makes it competitive with other techniques, such as the more high tech carbon capture and storage, external (CCS).

A variety of countries are presently trialling this technology, external but it has yet to be released commercially.

Growing jatropha not only absorbs CO2 however has other advantages. The plants would assist to make desert locations more habitable, and the plant's seeds can be gathered for biofuel say the scientists, offering an economic return.

"Jatropha is perfect to be turned into biokerosene - it is even much better than biodiesel," stated Prof Becker.

But other specialists in this area are not encouraged. They point to the fact that in 2007 and 2008 great deals of jatropha trees were planted for biofuel, particularly in Africa. But much of these ventures ended in tears,, external as the plants were not extremely successful in managing dry conditions.

Lucy Hurn is the biofuels project manager for the charity, Actionaid. She states that while jatropha was when seen as the great, green hope the reality was really different.

"When jatropha was presented it was seen as a wonder crop, it would grow on scrubland or marginal land," she stated.

"But there are typically individuals who require minimal land to graze their animals, they are getting food from that area - we would not class the land as limited."

She pointed out that jatropha is highly harmful and can contaminate the land it is grown on, even in a desert. And she also had concerns about the fairness of the concept.

"It is still someone else's land. Why go in and grow these massive plantations to deal with an issue these individuals didn't in fact cause?"

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