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北美托福机经英文版原文(5)

2011-11-09来源:和谐英语
  1. 讲生物的2个阶段,怎么改善土地之流
  第1段:任何ecosystem都有生物组成的轮换 (turn) 每种组成都有不同stage 然后都在它们最后一个stage达到climax (有题)。
  第2段:第一个阶段从一片荒芜之中(severe=extreme condition有题) [高或低温,土地不存储水,大风?] 勇敢生长出来的是pioneer plants,此物可抵抗一切不良条件。之后他们用他们的根改善土壤条件,然后死了之后又成为有机养料(organic material)。有了这些植物之后会有昆虫、小动物来吃他们。鸟会来吃虫子。于是最后达到climax。
  第3段:此时,捡便宜的subsequent植物出现鸟,他们往往是高大的植物(比如某berry),通过来觅食的鸟的粪便中留下种子。他们生长起来之后,通过叶子产生大量shadow,然后让楼下的暗无天日,于是长江后浪推前浪,先锋植物死光光。之后楼下就会生成一堆无阳光也能活的小植物出来。到达stage 2的climax了。
  第4段:以沙丘(sand dune)来举例,沙丘不仅是不毛之地(旱 温差大),还经常打滚,一打滚就把东西全埋进去了。(这里还提到它们离海往往还很近,忘了是要说啥,然后还有题,问为啥要提离水近) 突然有种无比牛x的草,被埋进去也死不掉,根还特别长,于是就把沙丘固定住了。后面就像上面所说各种后续植物生出来。
  Ecological Succession 生态演替。
  主要讲植物对环境的改善,将不毛之地变成动物天堂,有很多stages。首先讲了第一个阶段,在不毛之地,气候和环境都很恶劣,只有适应性很强的植物可以苟且生存。(考点,同义句)这些低等植物抵御干旱和强烈光照等恶劣环境,慢慢改善着脚下的土地,死后就变成腐殖质,给土地营养。它们还吸引来了哺乳动物和鸟类。(考点,它们是怎么吸引的)然后环境进一步改善。进入了第二阶段,大型的植物来了,它们靠自己的叶子给土地提供庇护,湿度和温度得到保证(考点,大型植物的作用),动物数量和种类也多了起来。最后达到了一个climax(考点,关于climax状态的阐释)。
  关于生物分布,pioneer植物的概念。通常都在严峻的环境下,比如相对比较极端的温度,干旱缺水等等。然后讲了PIONEER植物来了之后如何(有辞汇题,*考的那个词*接decay什么什么。。。我貌似选了=later)。后来pioneer植物慢慢把这种极端环境改造成了较为适宜的环境,慢慢动物植物也都来了。举例一个沙漠里的pioneer植物的过程。总体来说我觉得就是一些天不怕地不怕比较小强型的植物先遣部队,在没有花香没有树高的荒芜地带认识世界改造世界造福后来动植物兄弟的血泪史。
  托福阅读真题题源:Ecological succession 生态演替
  Ecological succession
  The structure of communities is constantly changing. All communities are subject to periodic disturbances, ranging from events that have only localized effects, such as the loss of a tree that creates a gap in the canopy of a forest, to those that have catastrophic consequences, which include wildfires that sweep across vast landscapes or storms that pound immense stretches of shoreline. Each new disturbance within a landscape creates an opportunity for a new species to colonize that region. New species also alter the character of the community, creating an environment that is suitable to even newer species. By this process, known as ecological succession, the structure of the community evolves over time.
  Types of succession
  Two different types of succession, primary and secondary, have been distinguished. Primary succession occurs in essentially lifeless areas—regions in which the soil is incapable of sustaining life as a result of such factors as lava flows, newly formed sand dunes, or rocks left from a retreating glacier. Secondary succession occurs in areas where a community that previously existed has been removed; it is typified by smaller-scale disturbances that do not eliminate all life and nutrients from the environment. Events such as a fire that sweeps across a grassland or a storm that uproots trees within a forest create patches of habitat that are colonized by early successional species. Depending on the extent of the disturbance, some species may survive, other species may be recolonized from nearby habitats, and others may actually be released from a dormant condition by the disturbance. For example, many plant species in fire-prone environments have seeds that remain dormant within the soil until the heat of a fire stimulates them to germinate.
  The process of succession
  Primary and secondary succession both create a continually changing mix of species within communities as disturbances of different intensities, sizes, and frequencies alter the landscape. The sequential progression of species during succession, however, is not random. At every stage certain species have evolved life histories to exploit the particular conditions of the community. This situation imposes a partially predictable sequence of change in the species composition of communities during succession. Initially only a small number of species from surrounding habitats are capable of thriving in a disturbed habitat. As new plant species take hold, they modify the habitat by altering such things as the amount of shade on the ground or the mineral composition of the soil. These changes allow other species that are better suited to this modified habitat to succeed the old species. These newer species are superseded, in turn, by still newer species. A similar succession of animal species occurs, and interactions between plants, animals, and environment influence the pattern and rate of successional change.
  In ecology, the final stage of biotic succession attainable by a plant community in an area under the environmental conditions present at a particular time. For example, cleared forests in the eastern United States progress from fields, to old fields (with colonizing trees and shrubs), to forests of these early colonists, and finally to climax communities of longer-lived tree species. The species composition of the climax community remains the same because all the species present successfully reproduce themselves and invading species fail to gain a foothold. Because climatic changes, ecological processes, and evolutionary processes cause changes in the environment over very long periods of time, the climax stage is not completely permanent.  
  2. Art Reformation and Influence
  主要讲了19世纪的艺术**,艺术家们要求艺术重返自然和本体。他们在绘画,建筑等各个方面充分反映着自己的艺术诉求。他们鄙视现代报纸和广告,认为他们不是艺术(考点,艺术家不干什么)。一个加拿大女人从小受到艺术教育,主要是waving,在艺术**的浪潮中受到薰陶。看过一次艺术展览后,受到启发,(插入题,this event nostalgia ……)她决定办艺术工厂,雇佣中产阶级在家赋闲妇女,解决她们的经济困难。(考点,她办工厂的原因)后来她发现其实很多有钱人不在乎慈善,他们买艺术品只是为了显摆品味,于是她开了Women Exchange,这样里面的女工可以生产各种各样的艺术品,不只是纺织品。(考点,她开的两种工厂有什么不同)之后的世界大战和1920大萧条造成了更多赋闲妇女,于是她开了更多工厂,遍布全国。(考点,为什么提大战和萧条)她把各地的产品集中船运到纽约的店铺来卖。(考点,我们可以从她的其他工厂的运行方式中推测出……)
  辞汇题 conceived = imagined;echoed — imitated
  美国近代中产阶级女性的手工手艺发展(大概)。刚开始讲美国近代art受到雅典和哪边的室内设计的影响,提到无机建筑和有机建筑的对比。然后讲有个叫wheels的女人,因为看到很多中产阶级女性放不下身段去做下等人的活儿,但因为civil war或者其他战争,变成寡妇或者blabla,遇到了经济困难,需要养活自己。于是wheels同学就创办了一个招收受过教育的中产阶级女人做类似女红一类的活儿和一些art的东西的学校叫SDA(缩写,全称忘记了),东西运往NY销得不错(有题问imply了什么,我选了这种art在当地没有受到支持)。接着她发现SDA有些局限,少了一些对其他art的关注,于是她貌似又在某地开了个另外的学校作坊,专注于……。
  讲艺术的,具体是说工业时代,人们用手工艺术来对抗工业艺术品,问了对抗形式特点是个except题,选项有什么通过广告方式,还有个通过手工制品来对抗,还有个什么的,第三个选项是说加入了模仿历史和生物的形式,我选了这个,然后说了个大娘叫华什么的,华大娘一生为艺术献身,小时候在一个学校学一种text艺术(是一个题干),大娘一生为公益事业而奋斗,给妇女穷人创造了机会(有题,问大娘开工厂的是什么,应该是为穷人经济困难的人帮助),然后在芝加哥参加了一个什么艺术展示(有题),东西运往NY销得不错,有题目问imply什么,我选的是东西主要在纽约销售,然后大娘加入了2个组织,有题目考2个的差别在哪,似乎是一个为穷人提供帮助,另一个由上层贵族参加名字叫SED。。。
  3. Amphibian Decline
  科学家发现最近很多两栖动物数量急剧减少,他们归咎于环境污染,全球暖化,大气层破坏等一系列问题。特别是酸雨和光辐射对两栖动物影响很大。于是单拿青蛙来研究。酸雨增加水的酸性,直接**蛙卵,破坏蛙的sperm(考点,酸雨如何影响青蛙)。光辐射带来疾病别且它和酸发生化学反应**青蛙(考点,光辐射如何影响青蛙)。青蛙由于皮肤薄且为它们的呼吸器官,于是它们更容易受到环境污染的影响。再则,青蛙有一种不良习惯,从被孵出来开始,它们就要找暖的地方或者直接晒太阳,于是它们更容易受到光辐射侵害(考点,青蛙为什么容易受到伤害)。最后,一些科学家认为这种数量减少不过是正常的fluctuation,不足为怪。但是,很多科学家说搜集证据要很多时间,等十多二十年后科学论证出来了才来保护两栖动物就太晚了(考点,反对正常波动理论的科学家态度)。
  辞汇题 separate — break up;seek — look for