题干

某生物兴趣小组对校园中四种不同植被类型的土壤中小动物类群的丰富度进行研究.

(1)进行土壤中小动物类群的丰富度调查常采用____ 法.

(2)土壤动物具有趋暗、趋湿、避高温的习性,为了探究土壤小动物类群丰富度,兴趣小组设计了如图所示装置,从选取的样土中收集小动物,他们这一装置不够完善,请你帮助该小组的同学们完善该装置:____ ,收集瓶中加入70%的酒精的用途是____ 

(3)校园中四种不同植被类型的土壤中小动物数量如图:

土壤动物群落数量出现明显的季节变化,单位面积土壤动物总数量在7月左右出现高峰期的原因可能是____ 

(4)土壤动物在生态系统中的成分一般是____ .其群落结构和数量与土壤中有机物的含量关系十分密切.分析上图可推测,四种植被类型中土壤中有机物含量最低的是____ .

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    I was sure that I was to be killed. I became terribly nervous. I searched in my pockets to see if there were any cigarettes, which had escaped their search. I found one and because of my shaking hands, I could barely get it to my lips. But I had no matches, they had taken those. I looked through the bars at my jailer. He did not make eye contact with me. I called out to him “Have you got a light?” He looked at me, shrugged and came over to light my cigarette. As he came close and lit the match, his eyes inadvertently(不经意地)locked with mine. At that moment, I smiled. I don't know why I did that. Perhaps it was nervousness, perhaps it was because, when you get very close, one to another, it is very hard not to smile. In any case, I smiled. In that instant, it was as though a spark jumped across the gap between our two hearts, our two human souls. I know he didn't want to, but my smile leaped through the bars and generated a smile on his lips, too. He lit my cigarette but stayed near, looking at me directly in the eyes and continuing to smile.

    "I kept smiling at him, now aware of him as a person and not just a jailer. And his looking at me seemed to have a new dimension too. “Do you have kids?” he asked. “Yes, here, here.” I took out my wallet and nervously fumbled for the pictures of my family. He, too, took out the pictures of his family and began to talk about his plans and hopes for them. My eyes filled with tears. I said that I feared that I'd never see my family again, never have the chance to see them grow up. Tears came to his eyes, too. "Suddenly, without another word, he unlocked my cell and silently led me out. Out of the jail, quietly and by back routes, out of the town. There, at the edge of town, he released me. And without another word, he turned back toward the town.

    “My life was saved by a smile.” Yes, the smile― the unaffected, unplanned, natural connection between people. I really believe that if that part of you and that part of me could recognize each other, we wouldn't be enemies. We couldn't have hate or envy or fear!