题干

成都郊区某乡镇过去以种植业为主,仅养殖少量家畜家禽,大量农作物秸秆除部分用作燃料外,大部分被丢弃.为了有效利用农作物秸秆,该乡镇去年开始发展生态农业,新建立了许多家畜家禽养殖场,建成了食用菌种植基地,还新建了几个大型沼气池,虽然农作物种植种类和面积没变,但经济效益大幅提高.请回答:

(1)太阳能输人生态系统的第一营养级后,是以____ 能的形式在生物群落中流动的,能量流动的渠道是____ .能量在相邻两营养级间的传递效率大约是____ .

(2)该乡镇发展生态农业时,主要增加了生态系统成分中____ 的种类和数量.调整结构后的生态系统,能够使能量更有效地被人们利用,原因是____ 

(3)部分家禽养殖户在增加营养的基础上延长光照时间,提高了家禽的产蛋率,该过程中光刺激传递的信息属于____ 信息.生态系统中,各种各样的信息在生物的____ 等方面起着重要作用.

(4)与森林生态系统相比较,农业生态系统的抵抗力稳定性更低,主要原因是____ .

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短文概写

    Why do people like what they like? Scientists have taken on the task of solving this mystery(奥秘)for ages. In the 1960s, psychologist Robert Zajonc conducted a series of experiments where he showed people nonsense words and random shapes. Afterward he asked his subjects which they preferred out of ever thing they had been shown. In study after study, people always chose the words and shapes they had seen the most. Their preference was for familiarity.

    This discovery was one of the most important findings in modern psychology. But the preference for familiarity has clear limits. People get tired of even their favorite songs and movies. On one hand, humans seek familiarity, because it makes them feel safe. On the other hand, people love the thrill of something new. This change between familiarity and discovery affects ns all the time- not just our preferences for pictures and songs, but also our preferences for ideas and even people.

    For that reason, the power of familiarity seems to be strongest when a person isn't expecting it. The opposite is also true: A surprise seems to work best when it contains some familiarity. Nobody knows this better than Raymond Loews, who is considered to be the "father of industrial design. He had a theory that he said could help artists sell anything to anyone. He called it MAYA --"Most Advanced Yet Acceptable""To sell something surprising, make it familiar; and to sell something familiar, make it surprising," he said.

    One of Loewy's final tasks was too add an element(要素)of familiarity to a truly new invention: NASA's first space station. Loewy's biggest contribution to the space station was that he insisted NASA install a window with a view of Earth. Today, tens of millions of people have seen this small detail in films about astronauts. It is hard to imagine a more perfect example of MAYA: a window to a new world can also show you home.