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英语煎蛋小学堂视频百科117:为什么贫瘠的地方生物多样性更丰富(MP3+中英双语)

cocotang 于2015-08-05发布 l 已有人浏览
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英语视频:煎蛋小学堂117:为什么贫瘠的地方生物多样性更丰富,以幽默诙谐的方式为你解答那些那些你意想不到的科学小知识,含有中英双语字幕视频,mp3下载。
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A soccer-field sized patch of forest in frigid Alaska has about 40 different species of plants,compared with about 70 in temperate England and 300 in the Amazonian rain forest.These biodiversity differences hold true for entire countries,too:England has 1500 plant species,while tropical Guyana,9000.

在极其寒冷的阿拉斯加 一块足球场大小的森林大约含有40种物种,与之相比 较温和的英国约有70种 亚马逊雨林则有300种。这种生物多样性差异对国家同样适用;英国有1500种植物,而热带圭亚有9000种.

The super diversity of tropical rainforests is only equalled in one other type of ecosystem on Earth:scrubby fire-prone shrublands that grow in western Australia and southern Africa.These shrublands may not look as majestic as tropical rainforests,but in a given area,they're home to similarly stupendous numbers of species.

热带雨林的生物多样性 仅相当于地球上另一个生态系统 澳大利亚西部和非洲南部 易发火灾的低矮灌木地 这些灌丛或许看起来没有热带雨林那么壮观,但在相同面积下 它们所包含的物种数是一样的。

Which doesn't necessarily mean that the rainforests and shrublands are easy places for plants to live.In fact,both ecosystems owe their enormous diversity,in part.to the fact that their soils have critically low supplies of nitrogen and especially phosphorus,nutrients plants need in order to grow.

这并不意味着热带雨林和灌丛是适宜植物生长的地方。事实上 这两个系统都不该拥有这么多物种,它们的土壤中极度缺氮和缺磷,这是植物生长所需的营养盐。

The plant world's leading biodiversity hotspots are,quite literally,dirt poor.Logically,it seems like richer soils should support more species.But in nature,as in human society,plenty of resources doesn't necessarily translate into "everyone gets plenty."In meadows,forests,and wetlands around the world,we consistently find more or bigger plants but fewer species where soil nutrients are highest.

也就是说 植物界生物多样性富饶区,其实非常贫瘠。按说 土地富饶的地方生物多样性应该更丰富。但是在自然界里 同人类社会一样,“资源丰富”并不意味着“人人富裕”。在全球的草甸,森林和湿地,我们发现均发现更多,或更大的植物 但是土壤肥沃的地方物种多样性更低。

The fastest spreading species soak up most of the extra nutrients,which lets them keep growing super fast,which lets their roots suck up so much water,and their leaves snatch up so much sunlight,that other,slower species actually get LESS of those resources than otherwise.So in rich soils,slower species die out while the fast-growers win big.

传播迅速的物种吸收了大部分的富余养分,这令它们持续疯长,令它们的根部吸收了巨多水,它们夺取了过多的阳光 以至于其他,其他生长缓慢的物种得到的资源变得极少。因此在土壤肥沃的地方,长得快的物种令生长缓慢的物种灭绝。

On the other hand,poor soils don't provide enough nutrient capital for fast growing plants to build their massive infrastructures and take all the resources.So poor soils inhibit the greedy and allow everyone else to scrabble by.We see this pattern in human society also there's a far greater number of businesses-mostly small-in poor countries,while fewer bigger companies dominate in rich countries.

另一方面,贫瘠的土壤无法为快速生长的植物提供足够的营养盐 因为它们无法建立巨大的地下根系夺取资源。因此贫瘠的土地扼杀了贪婪 令大家都能挣扎成活。我们在人类社会中也能看到这种现象 贫穷的国家 拥有更多的小企业,而富裕的国家受少数大企业控制。

But crummy soil isn't the only thing that helps super high diversity blossom:for example,beaches,mountaintops,and other places frequently ravaged by harsh weather or catastrophic events have poor soils and few plant species.

但是 贫瘠的土壤并不是催生丰富多样性的唯一因素,例如海洋,山顶和其他那些 频繁被污水或灾变事件破坏的地方 土地贫瘠 物种也很少。

The other major prerequisite for hyper diversity is time.On most of the planet,glaciers regularly bulldoze away ecosystems and grind up mineral-rich rock,creating new soil perfect for growth but not diversity.However,our high-diversity rainforests and shrublands have spent millions of years beyond the reach of the ice sheets,leaving their residents plenty of undisturbed time to evolve a wide variety of ingenious strategies for surviving nutrient poverty strategies that have allowed for the development of tall,diverse,rainforests in wet poor soils and scrubby,diverse,shrublands in dry poor soils.

另一个丰富物种多样性的条件是时间。地球上大多数地方,冰川会定期清理生态系统并且磨碎含矿物的岩石,形成新的适宜生长的土壤 但对多样性无益。然而 我们多样性丰富的热带雨林和灌木地 在冰川触及不到的地方花了数百万年,为它们的居民提供了漫长的安逸时间 让它们进化出了各种在贫瘠土地上生存的巧妙策略 这些策略令 潮湿贫瘠的雨林里长出各种各样高大的树木 干燥贫瘠的灌木地长出各种各样矮小的树丛。

The human landscape also seems to follow a similar pattern,with the highest cultural and linguistic diversity as well as the greatest number of businesses in climatically stable places.where humans have been the longest and where economic resources are scarce.

人类社会似乎也有着相似的模式,在气候稳定的地方 文化深厚,语言多样化 同时商业种类也很繁多 这些地方人类居住史很漫长并且经济资源匮乏。

So in some ways,the poorest places on earth are actually (also)the richest.

因此从某种意义来说,世界上最贫穷的地方实际上也是最富裕的地方。

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