Water Pollution

　　Water Pollution 　　Water pollution is caused by waste from factories and cities. Oceans are able to clean themselves, but certain seas, once they become dirty, are not able to do so. One example is the Mediterranean which lies between Europe and Africa. It has onlyeone narrow entrance to the ocean in the west. On quarter of the shores of the Mediterranean are polluted and are no longer safe for swimming, as a lot of diseases are present in the water. In most places it is not safe to eat the fish. 　　Lakes also have the same problems. Lake Baikal in Asia was once the cleanest in the world, with over 700 different kinds of plant and animal life. Now, however, the waters of this great lake, which is also the worlds deepest , have been dirtied by waste from a chemical factory. 　　In 1989 an oil tanker hit a rock off the northwest coast of Alaska. 35,000 tons of oil poured into the sea. The accident was one of the worst in history. More than 34,000 birds and 10,000 animals were killed. 4,800 square kilometres of ocean were polluted. 　　水污染发生在江海湖泊。作者举例说明一些海域及湖泊的污染原因及状况。读者可用此题目从不同的角度加以描述或议论。 　　水污染 　　水的污染是由于工厂和城市的废物引起的。大洋能够自身清除污染，但是某些海域一旦被污染，却没有自身清污的能力。位于欧洲和非洲之间的地中海就是一个例子。它只在西部有一个狭窄的通往大洋的入口。四分之一的地中海海岸被污染了，而且由于水中带有大量病菌，所以在水中游泳就不再安全了。大多数地方，吃鱼也不保险。 　　湖泊也遇到了同样的问题。亚洲的贝加尔湖曾经是世界上最清洁的湖，湖里有700多种不同的植物和动物。而如今这个大湖也是世界上最深的湖湖水已经被一家化工厂的废物污染了。 　　1989年，一艘油轮在坷拉斯加西北海岸的海面上触礁，35 000吨汕倾入大海。这是历史上最严重的事故之一。34 000多只鸟和10 000多头动物死亡，4 800平方公里的海洋受到污染。