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[科学美国人60秒] 【整理】SSS 2008-02-11

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For years, advocates have touted that biofuel is such a clean burning alternative to gasolines. Now a pair of study published in Feb eight issue of Science conclude that the biofuel may do more harm to enviroment than good. The researcher caculated that the indirect costs growing the crops that turn into the biofuels. To plant the crops corn and sugarcane and soybeans from which bio-diesel and bio-ethanol are made,farmers would firstly clean the forests and grasslands. That process turns out would generate more carbon dioxide that we save by swearing off our fossil fuel. We take centuries to pay off that carbon debt. For example, the scientists fingure out that we take 319 years of using the ethanol from the soybeens to make up for the extra carbon released by chopping down the forests needed to grow the crops. Of course, more co2 in antermospher means more glabol warming. So biofuel may acutually exaggrate problem than man can solve. Something to think about is we move on forward on producing legal friendly fossfuel. As one of scientists puts it: we should make sure our cure is worth than the disease

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