假设将水稻田里的杂划全部清除掉，稻田生态系统中

【名词&注释】

物种多样性(species diversity)、太阳能(solar energy)

[单选题]假设将水稻田里的杂划全部清除掉，稻田生态系统中

A. 水稻害虫密度将下降 能量流动的营养级数减少 水稻固定的太阳能增加 物种多样性上升

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[单选题]CSports can help you keep fit and get in touch with nature. However, whether you are on the mountains, in the waves, or on the grassland, you should be aware that your sport of choice might have great influence on the environment.

A. Some sports are resource-hungry. Golf, as you may know, eats up not only large areas of countryside, but also tons of water. Besides, all sorts of chemicals and huge amounts of energy are used to keep its courses (球场) in good condition. This causes major environmental effects. For example, in the dry regions of Portugal and Spain, golf is often held responsible for serious water shortage in some local areas.
B. There are many environment-friendly sports. Power walking is one of them that you could take up today. You don’t need any special equipment except a good pair of shoes; and you don’t have to worry about resources and your purse. Simple and free, power walking can also keep you fit. If you walk regularly, it will be good for your heart and bones. Experts say that 20 minutes of power walking daily can make you feel less anxious, sleep well and have better weight control.
C. Whatever sport you take up, you can make it greener by using environment-friendly equipment and buying products made from recycled materials. But the final goal should be “green gyms”. They are better replacements for traditional health clubs and modern sports centers. Members of green gyms play sports outdoors, in the countryside or other open spaces. There is no special requirement for you to start your membership. And best of all, it’s free.
D. 64. Which of the following is the author most probably in favor of?
E. Cycling around a lake.
F. Motor racing in the desert.
G. Playing basketball in a gym.
H. Swimming in a sports center.

[单选题]筛管分子间有穿孔相通，其中有联络索通过。( )

A. 正确
B. 错误

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