题干

关于农田退耕还林后的变化,推测不合理的是(      )

A:退耕还林是群落的次生演替过程

B:群落的总能量增多,营养结构更复杂

C:抵抗力稳定性增强,恢复力稳定性降低

D:种群增长速率持续上升,种群密度增加

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答案(点此获取答案解析)

D

同类题3

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    Some of the world's most famous musicians recently gathered in Paris and New Orleans to celebrate the first annual International Jazz Day. UNESCO( United Nations Educational, Scientific and Cultural Organization) recently set April 30 as a day to raise awareness of jazz music, its significance, and its potential as a unifying(联合) voice across cultures.

    Despite the celebrations, though, in the U.S. the jazz audience continues to shrink and grow older, and the music has failed to connect with younger generations.

    It's Jason Moran's job to help change that. As the Kennedy Center's artistic adviser for jazz, Moran hopes to widen the audience for jazz, make the music more accessible, and preserve its history and culture.

    "Jazz seems like it's not really a part of the American appetite," Moran tells National Public Radio's reporter Neal Conan. "What I'm hoping to accomplish is that my generation and younger start to reconsider and understand that jazz is not black and write anymore. It's actually color, and it's actually digital."

    Moran says one of the problems with jazz today is that the entertainment aspect of the music has been lost. "The music can't be presented today the way it was in 1908 or 1958. It has to continue to move, because the way the world works is not the same," says Moran.

    Last year, Moran worked on a project that arranged Fats Waller's music for a dance party, "just to kind of put it back in the mind that Waller is dance music as much as it is concert music," says Moran. "For me, it's the recontextualization. In music, where does the emotion(情感) lie? Are we, as humans, gaining any insight(感悟) on how talk about ourselves and how something as abstract as a Charlie Parker record gets us into a dialogue about our emotions and our thoughts? Sometimes we lose sight that the music has a wider context," says Moran, "so I want to continue those dialogues. Those are the things I want to foster."

同类题5

根据短文内容,从A、B、C、D四个选项中选出一个能填入相应空格内的最佳答案。

    Tom worked hard in an office. But it seemed that there was little change in his life. He was unhappy and didn't want to improve himself any more. His father, Joe, knew this and decided to have a talk with 1 .

    One day, Tom and his father went for a walk after dinner. 2 they were walking along a river, Tom said, “Dad, you always tell me to learn something new. To be3, I don't want to make any change.”

    Joe looked in the river, saw a dead 4and pointed at it.

    “Tom, what is that over there?”

    “It's a dead fish.”

    “What's the fish doing?”

    “It's moving down with the running water.”

    “But the fish is dead. 5 can it be moving?” asked Joe.

    “It's moving as the river is moving.”

    Joe turned to his son and said, “Life is 6 the river. It's always moving and always changing. Some people don't want to change, but their life is always changing whether they like it or not. A dead fish only moves along the river, while a living fish can control its journey. What's your choice if you want to live a 7 life?”

    This made Tom 8 his aunt who had already stopped learning and developing. And she just stayed the way she used to be, living like a dead fish.

    Guided by his 9 , Tom understood what he said. He didn't want to become a person like his aunt. So he made up his mind to 10  learning and developing himself.