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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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RE: Subsidies distort the market
By Entropy42 on 12/8/2008 10:44:29 AM , Rating: 2
There must be some sort of credit for just growing the corn, without even harvesting and selling it. There is a cornfield near me (MI) that is just sitting there, still unharvested. And they obviously don't plan to, since its already snowing here.

RE: Subsidies distort the market
By JonnyDough on 12/8/2008 4:33:30 PM , Rating: 2
No offense, but you people are idiots. Corn can stand freely in a field after a snowfall for three reasons. One is silage. The other is rot. Sometimes a farmer leaves corn so he has a fence line or tree line to hunt deer off of (illegal in many states, unless he has a special permit designed to help farmers minimize crop damage).

For the post before yours:

Daylight savings does not decrease the day. The amount of daylight in a day, however does decrease after the summer solstice. I'm sure farmers are aware of both of these things. I highly doubt farmers are idiots like you might assume. They are good at what they do, many of them excel at being veterinarians, carpenters, mechanics, merchants, and market researchers ALL AT THE SAME TIME. Don't anyone ever dare to call a modern farmer stupid (partly because anyone willing to get into a pen with a bull and stick medicine up it's ass has more balls than most people I know. Hands of leather are enough of a warning not to pick a fight.

Speaking of which, don't ever pick a fight with an Amish kid, no matter how thin he looks. I've been around a few, and I can tell you that when you're raised with a strict disciplinarian father and 7 brothers, and work is pretty much life - you're likely to be pretty tough.

Farmers practically invented the calendar, they know exactly what the weather is doing 99% of the time. They wake up at 4am to milk cows and brave the weather to pull crops in, or to mend a fence and catch their cattle in the middle of a storm. Weather and seasonal change affects them much more than it affects most people.

And for the post before that one:

Farmers also will plant what stands to get the biggest gain at the lowest risk. They often weigh their odds. Crops that are likely to do well in almost any weather reap little money because a monkey could grow them. Crops that bring in more but only grow well if there's a lot of rain or not too much wind or an early frost or something, are riskier. The seed costs more and the entire field can fail. Not only do they have to watch the weather, but they have to keep an eye on market prices for crops, and reports about what farmers around the U.S. and the world are planting - as they have an effect on sale timing. You sit on seed corn too long, it rots and you can't sell it. You sell it at the wrong time and you get less for it. Farmers are gamblers. They are also investment and savings bankers. They have to know how to save and invest to be able to get through a bad year following a good one.

RE: Subsidies distort the market
By Reclaimer77 on 12/8/08, Rating: 0
RE: Subsidies distort the market
By Myg on 12/8/2008 7:26:16 PM , Rating: 2
He wouldnt be wrong to support such an idea; they would understand the meaning of hard work and the value of real labour...

It doesnt mean we should all live that way of life; it just means we should learn the lessons offered, which I am sure they would be more then glad to share.

RE: Subsidies distort the market
By JonnyDough on 12/9/2008 5:16:10 PM , Rating: 2
This coming from a guy who kisses Mashers backside every chance he can.

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