2. 外语
  3. In my neighborhood in the early 1980s, we spent the summer playing kickball. Our front lawns were a constant. We took their soft

In my neighborhood in the early 1980s, we spent the summer playing kickball. Our front lawns were a constant. We took their soft

admin2012-08-05  52
问题     In my neighborhood in the early 1980s, we spent the summer playing kickball. Our front lawns were a constant. We took their soft, grassy goodness for granted, until the lawn service arrived. Now and then, a tanker truck pulled up, and two men in coveralls sprayed who knows what all over our grass. Before they left, they put up little flags reminding us to keep off the lawn for 24 hours. For emphasis—or the pre-literate—the signs featured a skull and crossbones. In part because of those tanker trucks, grass has taken a major public relations hit. Its constant need for fertilizer and herbicides is supposed to make it an environmental disaster.
    Grass is now the biggest crop in the Chesaeake Bay area, and will soon surpass all crops combined. Excess chemicals placed on lawns at the wrong time or carelessly scattered on impermeable surfaces can end up in the fragile bay. Excess fertilizer, to take just one example, contributes to eutrophication, which occurs when too many phosphates and nitrates build up in a body of water, feeding an explosion of algae. When the algae decompose in the bay, they use up much of the available oxygen, choking off crabs and other marine life.
    So is it possible to be environmentally sensitive and have a good lawn? Yes, according to Frank Rossi, an associate professor of horticulture at Cornell University. It’s simple, he says. Once your grass gets going, here comes the really hard part if you’re trying to maintain a healthy lawn without chemical intervention; Leave it alone.
    You read that right. According to Rossi, the biggest mistake people make is failing to control their impulse to intervene. They mow too short and too often. They water too much. They fertilize too frequently.
    And, when things go bad, they break out massive amounts of chemicals to try to control the advancing weeds.
    You should mow your grass to a height of three inches. And don’t mow it again for 10 days. Two weeks if you can stand it. As for fertilizer, do it twice a year, at most. But don’t even think about doing it in the early spring. As for watering, do it only once or twice a week. If mushrooms develop, you’re watering way too much—and wasting water. It’s better to give your lawn a good weekly soaking than to water a little every day.
    One last tip: You don’t need perfectly uniform grass all the time. " This is a lot easier if you don’t try to make your lawn look like the center field at Nationals Stadium," cautions Rossi. In other words, if you can roll a kickball on it, you can be content.
What is eutrophication?
选项 A、A process of destroying water ecosystem.
B、A result caused by algae decomposition.
C、A phenomenon occurred with fertilizer use.
D、A place full of chemicals and algae.
答案A
解析 细节题。根据关键词eutrophication定位至第二段第三句。根据关键词之后的解释说明，磷酸盐和硝酸盐过度激增时，就会引起藻类的大爆发，之后藻类的分解则会用尽水体中的氧气，导致水生生物窒息而死，因此这是一种破坏水体生态体系的过程，A为答案。
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