SSS 2008-07-30
时间：2018-12-24 作者：英语课 分类：Scientific American(七)月
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This is Scientific American's 60-Second Science, I‘m Karen Hopkin. This will just take a minute.
Biofuels sound like such a good idea. A clean-burning fuel that reduces our need for foreign oil. What’s not to like? Well, for one thing, turning corn into biodiesel could be taking food off hungry people’s plates. “Okay,” biofuel advocates say, “suppose we just use the stems and leaves that are left over after crops are harvested? That should solve the problem.” Well, maybe not entirely 1. Because removing that so-called crop residue 2 takes food away from soil microbes. They convert that material into the nutrients 3 that crops need. So says USDA scientist Ann Kennedy of Washington State University. Microbes break down crop residue to form organic matter—the stuff that gives soil its rich, dark color. Organic matter, in turn, provides nutrients, helps the soil retain water, and prevents erosion. So, if you harvest the crop residue to produce biofuels, you remove the materials that are fodder 4 for the bugs 5 that make organic matter. Soil quality would drop, and farmers would have to find some other way to fertilize 6 their fields. So biofuels are not a magic bullet. Maybe you should just eat the corn and ride your bike.
Thanks for the minute, for Scientific American s 60-Second Science, I m Karen Hopkin.
- The fire was entirely caused by their neglect of duty. 那场火灾完全是由于他们失职而引起的。
- His life was entirely given up to the educational work. 他的一生统统献给了教育工作。
- Mary scraped the residue of food from the plates before putting them under water.玛丽在把盘子放入水之前先刮去上面的食物残渣。
- Pesticide persistence beyond the critical period for control leads to residue problems.农药一旦超过控制的临界期，就会导致残留问题。
- a lack of essential nutrients 基本营养的缺乏
- Nutrients are absorbed into the bloodstream. 营养素被吸收进血液。 来自《简明英汉词典》
- Grass mowed and cured for use as fodder.割下来晒干用作饲料的草。
- Guaranteed salt intake, no matter which normal fodder.不管是那一种正常的草料，保证盐的摄取。