ranching, building of dams and highways, and mining.
The tropical rain forest is natural recycle, provider and protector for our planet; it supports the ecosystem in the world.
Deforestation is endangering this ecosystem, and could cause at least one-fourth of all species on Earth to vanish in the next 25 years. Burning these forests releases carbon and decreases oxygen in the atmosphere, causing the global warming.
Protecting all forests is the key to our survival on this planet.
B - Air pollution is the result of mans use of chemicals, and is a common hazard in both industrial and developing countries. One form of air pollution is acid rains.
Acid rain results from the release into the atmosphere of sulfur oxide and nitrogen oxide. Electrical plants, industrial boilers and automobiles are among chief sources of these emissions. The gases react with water droplets, forming a mixture of sulfuric acid and nitric acid, this mixture returns to earth in the form of acid rain, mist or snow.
Acid rain is killing vast stretches of forests in Canada, the United States, and central and northern Europe. Acid rain has acidified lakes and streams making them unable to support fish, wildlife, plants or insects.
С - Oceans cover more than 70 of the Earths surface. Despite the vastness of this area, we know little about it. Life began in the ocean more than 3. 5 billion years ago. Today the ocean supports a wealth of simple and complex sea life from phytoplankton to marine mammals. But human beings ignore and misunderstand the importance of oceans. There is widespread pollution and disruption of our coastal waters, whales and dolphins are hunted to near extinction, and many fishing areas are being depleted.
The oceans do not belong to a single
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