British scientists to invent Carbon-removing soil
According to a press release from the British Embassy in Beijing, aresearch team from Newcastle University in the UK is trying todesign soils that can remove carbon from the atmosphere in a costeffective way - permanently.
"Scientists have known about the possibility of using soil asacarbon 'sink' for some time," said Professor Manning ofsoilscience at the University, who is leading the research. "Butno-oneelse has tried to design soils expressly for the purposeofremoving and permanently locking up carbon."
Plants, crops and trees naturally absorb atmospheric carbondioxide(CO2) during photosynthesis and then pump surplus carbonthroughtheir roots into the earth around them. With most soils,much ofthis carbon escapes to the atmosphere or entersgroundwater.
But the team believes that in soils containingcalcium-bearingsilicates (natural or man-made) the carbon thatoozes out of aplant's roots may react with the calcium to form theharmlessmineral, calcium carbonate. The most common natural formsofcalcium carbonate are chalk, limestone and marble.
The carbon then stays securely locked in the calcium carbonatethatremains in the soil, close to the plant's roots, in the formof acoating on pebbles or as grains.
The scientists are investigating whether this process occurs. Ifitdoes, then it would encourage the growth of more plants, cropsandthe like in places where calcium-rich soils already exist.
It would also open prospects for tailor-made soils (withaddedcalcium silicates or specific plants) that optimizecarbon-capture.Such soils could play a valuable role in carbonabatement all overthe globe.
The team members will first try to detect calcium carbonateinnatural soils that have developed on top of calcium-rich rocksorbeen exposed to concrete dust (that contains man-madecalciumsilicates).
They will then study artificial soils made at the university fromamixture of compost and calcium-rich rock. Finally, they willgrowplants in soils made to contain a high level of calciumsilicatesand then monitor the accumulation of calcium carbonatethere.
"Once we have confirmed the feasibility of this carbonsequestrationmethod, we can develop a computer model that predictshow muchcalcium carbonate will form in specific types of soil, andhowquickly.
"That will help us to engineer soils with optimum qualities fromacarbon abatement perspective. A key benefit is thatcombatingclimate change in this way promises to be cheap comparedwith otherprocesses," he added.
A significant scope could exist to incorporatecalcium-rich,carbon-locking soils in land restoration, landremediation andother development projects. Growing bio-energy cropson these soilscould be one attractive option.
"The process we are exploring might be able to contributearound5-10 percent of the UK's carbon reduction targets in thefuture,"said Professor Manning. "We could potentially seeapplications in2-3 years, including a number of 'quick wins' in thelandrestoration sector."
By People's Daily Online