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Not so green: corn ethanol reduces the soil carbon, increasing emissions and possibly contributing to warming. This effect is worsened if the leaves are removed for biofuel production, as some have suggested.  (Source: Don Hamerman)

Professor DeLucia of the University of Illinois and his colleagues have completed a massive new study, showing just how bad for the environment corn, and especially sugarcane, ethanol may be. It also shows grass ethanol can be very beneficial to cutting carbon, on the other hand.  (Source: Don Hamerman)

Replanting corn and sugarcane land with biofuel grass can help undo the damage done by these crops, the study suggests.  (Source: Don Hamerman)
A new study shows that switching from corn ethanol to grass may have great benefits

The ethanol business is a booming market, buoyed by several years of high gas prices.  While hampered somewhat by falling petrol costs, the market is seeing support from big investors like GM and is producing millions of gallons fuel yearly, with pumps expanding across the country.

However, while most agree that moving away from reliance on insecure, depletable oil is a good thing, there are also significant downsides to corn ethanol production, the current primary form of ethanol produced.  As discussed previously at DailyTech, corn ethanol is cited for higher food costs.  Additionally, it may not be as green from a carbon perspective as people think.

Companies like Coskata are looking to use alternatives such as quick growing grasses or wood waste to fuel their ethanol production.  Now a new study shows that not only does such production help to normalize food prices, it also helps cut down on excess atmospheric carbon.

A study from the University of Illinois confirms that some sources of biofuels can actually increase emissions of carbon dioxide, while others can decrease them.  The key is what you grow and where you grow it. 

The study compiled soil carbon information from dozens of other studies in order to get the big picture.  What it observes is that the amount of carbon that exists in the soil is increased by letting decomposing plant matter sit and eventually be absorbed into the earth, while tilling and plowing decreases the carbon in the soil, releasing it into the atmosphere.

Explains Evan DeLucia, a professor of plant biology at Illinois, "From the time that John Deere invented the steel plow, which made it possible to break the prairie sod and begin farming this part of the world, the application of row crop agriculture to the Midwest has caused a reduction of soil carbon of about 50 percent  The biggest terrestrial pool of carbon is in the soil. The top meter of soil holds more than three times the amount of carbon stored in either vegetation or the atmosphere, so if you do little things to change the amount of carbon in the soil it has a huge impact on the atmosphere and thus global warming."

Corn ethanol increases emissions, according to the study, because corn must be constantly replanted, and replanting requires tilling the fields.  Switchgrass, Miscanthus, and other fast-growing grasses, however, require no tilling and can grow wild, greatly increasing the soil's carbon and decreasing emissions.

Furthermore, these sources have more carbon density than corn, so once cost-efficient ways are created to process them, cellulosic ethanol should require much less land to produce than corn ethanol.

The study is significant, says Professor DeLucia as currently 20 percent of the U.S.'s corn crop goes to ethanol.  He describes "so we began with the hypothesis that it might be good for soil carbon to put a perennial biofuel crop on the landscape instead of corn."

From there they delved into massive amounts of information on soil carbon levels on land growing corn, sugar cane, Miscanthus, switchgrass and native prairie grasses, taking into consideration many factors.

They found that sugarcane, used greatly by Brazil's ethanol industry, is the worst offender when it comes to biofuels.  Sugarcane planted on native land slashes the carbon content, releasing vast amounts of carbon into the air.  Whereas perennial grasses add to soil carbon's base level each year, sugarcane land would require a century just to recover to the base level.

Corn showed similar, but lesser problems.  These problems could be alleviated somewhat by leaving more of the corn stover (plant waste) on the field, but the carbon was still cut significantly.

Losses from the initial planting of Miscanthus, switchgrass or native perennial grasses by on converted corn or sugarcane land took very little time to be neutralized thanks to great yearly gains in soil carbon.  Professor DeLucia states, "Consistent with our hypothesis, the perennial feedstocks like Miscanthus and switchgrass start building soil carbon very, very early on.  From a purely carbon perspective, our research indicates that putting perennial biofuel crops on landscapes that are dominated by annual row crops will have a positive effect on soil carbon."

These conclusions, he says, walk the study unintentionally "seems to walk you right into the food for fuel debate".  But he says that it just makes sense to plant grasses as biofuel feedstocks, even from a purely carbon-conscious perspective.

The research will be featured in the journal Global Change Biology Bioenergy next month.



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sky rocketing corn prices
By Dreifort on 12/8/2008 12:00:56 PM , Rating: 3
Ok, first there was the big boom in the corn/biofuel market. So naturally, speculators drove the price of corn through the roof (just as they did with oil). Hedge investors said - corn is the next hot item, so the price jumped up. These same guys will now see corn like they saw oil (over the summer) - a rare commodity as production was low and gloom & doom oil-won't-be-around-forever-talk.

So first, investors drove the price of corn up because of demand and few resources committed to developing corn ethanol. Supply & demand. Now with news that corn is "bad for the environment".... these same investors will see the gloom & doom with corn and see the corn-is-bad-for-the-earth-talk. This means less corn (due to over regulation and worries of a corn killed earth). So now corn prices will soar -- again.

Damn can of corn use to be $0.29...then jumped to $1.99...what's next $10 for a can of corn?

What happened to normal inflation of an annual average rate of 4% over the previous 20 years? hmmmm...

The problem is the media got more involved. Now it's "Corn! Bad for you, bad for your kids...and bad for the earth! News at 11."

The media has played a huge part in driving prices up and down and overplaying environmental issues. Guess that's what happened when Ted Turner initiated the 24/7 cable news coverage. ***-hole. News channels have too much time on their hands and overkill every story.

There are real issues with carbon deposits and hurricanes shutting down oil refineries for... 4 days (OMG! the horror!). But we consumers pay the price in the end when the media influences the markets which in turn influence the prices we pay at the pump or grocery or anywhere.

I blame Ted Turner for all this.




RE: sky rocketing corn prices
By FITCamaro on 12/8/2008 12:11:34 PM , Rating: 1
Agreed. The media is largely responsible for wild price swings we've seen in the past several years. I wish they'd just shut the f*ck up and let people formulate an opinion on their own. Part of why I never watch the news anymore.


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