2. 职称英语
  3. In 1798 the political economist Malthus predicted that in time mankind would

In 1798 the political economist Malthus predicted that in time mankind would

游客2025-03-24  6
问题     In 1798 the political economist Malthus predicted that in time mankind would face starvation, having outgrown the available food supplies. Today, a century and a half later, there are still experts who forecast the same global disaster—unless urgent measures are taken to prevent it.
    By the end of the present century there may well be over five thousand million people living on this globe, an increase of over fifty percent on today’s figure. In order to keep pace with this increase in mankind the farmers of the world will have to step up their production of food by at least two percent every year. Such a rate of increase has never been maintained in any country by conventional methods of agriculture, despite modern mechanization and the widespread use of fertilizers. There are no large worthwhile reserves of potential farmland remaining, and good fertile land is continually being changed into industrial use. Moreover, erosion of the soil takes a constant toll (损失).
    Intensive research, carried out over many years in all manners of climate conditions, has produced a revolutionary method of growing crops without using any soil at all. Hydroponics (水栽 法), as this technique is called, may well be the answer to all our food worries; already it has accomplished wonders in producing huge crops. Hydroponics was once a complicated and expensive business, now it is well out of the experimental stage. Labor costs are far lower than when normal methods of agriculture are employed. In fact, it is a completely automatic system. There is no hard manual work, no digging or ploughing, and no weeding to speak of. Yields can be far higher than they are in soil. [br] Which of the following statements is NOT true of hydroponics?
选项 A、Hydroponics is still too complicated and expensive for practical use.
B、Hydroponics is considered a revolutionary method of agriculture.
C、Hydroponics has created wonders in agriculture.
D、Hydroponics has already been employed in food production.
答案 A
解析 本题是一道判断是非题。问关于水栽法，下面哪个选项是不正确的。根据文章第三段第三句至段末，水栽法曾经很复杂而且成本很高，但现在这种方法已不再处于试验阶段了。利用这种栽培方法，劳动力的成本远远低于一般农业栽培法的成本。事实上，水栽法是一种完全自动的体系。无需艰苦的手工劳动，无需耕地、犁地，更不需要除草。而产量却能比土栽法高出许多。因此，本题的正确答案应是A“水栽法仍然太复杂昂贵，不实用”。
转载请注明原文地址:https://tihaiku.com/zcyy/4011003.html
相关试题推荐
随机试题
最新回复(0)