高中英语人教版高二下课文03

[03:47.76]海洋生物利用水密度。
[03:51.03]With the right kind of body,it is possible to float around in the ocean
[03:54.31]有合适的体形，在海洋中就能四处漂浮，
[03:57.58]and let the water do the work.
[03:59.62]让海水发挥作用。
[04:01.66]When water freezes,its density decreases.
[04:04.30]当水结冰时，它密度会减少。
[04:06.94]If it did not,the oceans would be frozen solid.
[04:09.76]若不是这样，整个海洋就会冻结成固体。
[04:12.58]HEAT CAPACITY
[04:14.05]热容
[04:15.53]Heat capacity is the amount of energy it takes to raise the temperature of a substance
[04:19.25]热容指的是一种物质的温度升高一摄氏度所需要的能量。
[04:22.97]by one degree centigrade.
[04:26.81]The heat capacity of water is relatively high.
[04:29.44]水的热容相对很高。
[04:32.07]Water can absorb and give off a lot of heat without big changes in temperature,
[04:35.89]温度改变不大，
[04:39.72]thus creating a stable environment.
[04:41.94]这样形成了稳定的环境。
[04:44.16]Most animals and plants are sensitive to large or sudden changes in temperature,
[04:47.70]大多数动物和植物对于巨大的或突然的温度变化很敏感，
[04:51.24]so the ocean is a safe and comfortable habitat.
[04:53.72]因而海洋是一既安全又舒适的栖息地。
[04:56.20]The water in the oceans also keeps the temperature of the earth steady
[04:59.32]海洋中的水也通过吸收或释放热量使地球的温度保持稳定。
[05:02.45]by absorbing and giving off heat.
[05:06.89]OCEAN MOTION
[05:08.41]海洋运动
[05:09.94]Since changes in slainity and temperature affect water's density,
[05:13.42]由于盐度和气温变化影响水的密度，
[05:16.89]the water in the ocean is always moving.
[05:19.37]海洋中的水一直在运动。
[05:21.85]Dense water sinks and less dense water is pushed to the surface.
[05:25.28]密度大的水下沉，密度较小的水被推到海面。
[05:28.70]This circulation adds energy to the marine ecosystems and moves nutrients around.
[05:32.93]这种循环为海洋生态系统增加了能量并使营养成分四处游动。
[05:37.16]Isn't it amazing that a single substance can be so important to our planet
[05:44.53]and even the whole universe?
[05:48.00]Water,which seems so simple and common,is what makes life possible.
[05:55.37]Of all the resources on earth-oil,gas,gold and so on
[06:04.12]-nothing is as precious as a drop of rain.
[06:09.08]Learning about the properties of water helps us understand life on our planet.
[06:16.45]The most important thing we can learn about water,however,
[06:21.91]is that we must protect it and use it wisely.
[06:27.06]Our future depends on it.
[06:30.92]INTEGRATING SKILLS
[06:34.15]综合技巧
[06:37.37]Reading  NATURE'S NURSERY:ESTUARIES
[06:40.05]阅读    自然的保育院：入海口
[06:42.73]As the oceans are the source of life ib earth,
[06:47.30]the estuaries are our planet's nurseries.
[06:52.06]An estuary is the body of water where a river meets the ocean.
[06:54.88]入海口就是一条河与海洋交汇的有很多水的地方。
[06:57.70]Salt water from the ocean and fresh water from the river
[07:00.43]从海中来的盐水和河流中来的淡水在入海口混合在一起。
[07:03.16]mix together in an estuary.
[07:07.23]This mixing of fresh and salt water
[07:09.41]这种盐水和淡水的混合
[07:11.60]creates a unique environment filled with life of all kinds-
[07:14.38]形成了一具独一无二的、充满各种生物的环境-
[07:17.16]a zone between the land and the sea.
[07:19.38]位于陆地与海洋之间的一个过渡的区域。
[07:21.60]Estuaries are the homes of thousands of animals and plants.
[07:24.40]入海口是成千上万种动植物的栖息地。
[07:27.19]Many cities and towns are built near estuaries,
[07:29.62]很多城市和城镇入海口建起，
[07:32.05]and a lot of fish is caught in estuaries.
[07:34.37]大量的鱼在入海口被捕捞。
[07:36.70]Estuaries are great places for nature's young ones.
[07:39.34]入海口对于自然中的细小生命来说是非常重要的地方。
[07:41.98]Here,animals can enjoy all the many of the benefits of teh oceans
[07:44.91]在这里，动物可以避开很多危险
[07:47.85]without having to fact many of the dangers.
[07:50.03]从而尽情享受海洋给其带来的益处。
[07:52.22]Tides provide energy for the ecosystems,
[07:54.54]潮汐为生态系统提供了能量，
[07:56.87]but estuaries are protected from waves and storms by islands,mud or sand.