7 Ask your partner to look at their list of five things they would like to buy and ask the following questions: Can you do without it?
How many do you have already?
How much will you use it?
How long will it last?
Could you borrow it from a friend or family member?
Are you able to clean and/or maintain it yourself?
Do you still want to buy it?
Ex. 13. Pre-Reading Questions Think about the following questions. How are rainforests different from other kinds of forests?
Why are large areas of rainforests typically cut down?
What percent of the world's rainforests have already been
cut down?
Match each word or phrase with its correct definition. canopy a. a covering hanging above
constitute b. what is possible to continue or maintain
deplete c. all of the plants in one area
devastating d. best
foliage e. to cut violently
lie fallow f. to leave land unused after harvesting
optimum g. leaves on trees and plants
slash h. to make up
sustainable i. overwhelming because it is tragic or shocking
vegetation j. to make smaller in amount or number
Deforestation It would be difficult to imagine life without the beauty and richness of forests. If humankind does not act quickly, however, planet Earth and all living creatures are in danger of losing forests forever. Deforestation has already resulted in the loss of over 80% of the natural forests of the world. Currently, the disappearance of forests worldwide constitutes a global 10 problem affecting the temperate forests of the Pacific Northwest area of the US and British Columbia, and more urgently, the tropical forests of Central and South America, Africa, Southeast Asia, and Australia.
Deforestation occurs for many reasons. In the temperate forests of the US and Canada, wood is harvested mainly for construction and paper products. In tropical rainforests, one of the most common reasons for deforestation is agriculture. Because the soil in many tropical regions is often nutrient-poor, and since 90% of nutrients in tropical forests are found in the vegetation (and not the soil), many farmers practice an agricultural method known 20 as "slash and burn." This consists of cutting down an area of trees in the rainforest and burning them to release their rich nutrients into the soil. This method is sustainable only if the population density does not exceed four people per square kilometer of land. When this is the case, each farm has enough land to let sections of it lie fallow for ten years or more, which is enough time for the land to renew itself. In recent years, however, the population density has often reached three times the optimum load. This results in land being used more intensively with no chance to recover. Under these conditions, slash and burn farming becomes only a temporary solution. Within two or three years, the soil becomes depleted, and the farmer must repeat the slash and burn process elsewhere, leaving the used land severely depleted.
Deforestation causes changes in the Earth's atmosphere. For example, deforestation in tropical areas disrupts the cycle of rain and evaporation by removing the moist canopy of foliage that trees provide. Undisturbed, this canopy helps create about one half of the rainfall in a tropical forest. When this water evaporates, it causes clouds to form and promotes future precipitation. When trees are cleared away, the canopy is lost and the cycle is disturbed. With less evaporation, the Earth's surface receives more energy from the sun. This can lead to the creation of deserts, ultimately causing atmospheric temperatures to rise. Moreover, when an area has been stripped of trees, rainfall and sunlight damage the topsoil, making it difficult for the forest to grow back.
Deforestation is also partially responsible for rising atmospheric levels of carbon dioxide. Forests release large amounts of carbon dioxide into the atmosphere when trees are cut, and especially when they are burned. The current yearly rate of carbon dioxide that enters the atmosphere from deforestation is about 1.6 billion metric tons. When we consider that the burning of fossil fuels releases approximately 6 billion metric tons of carbon dioxide per year, it is clear the burning of trees and vegetation contributes significantly to carbon dioxide levels in the atmosphere. These rising levels are a cause for concern because they will be responsible for 15% of the increase in global temperatures between 1990 and 2025.
In addition, deforestation causes the extinction of thousands of species of 55 wildlife annually. It is estimated that worldwide, 5 to 80 million kinds of animals and plants make up the biodiversity of the Earth, but only about 1.5 million have been studied and named by scientists. Tropical rainforests, which cover about 7% of the Earth's land, are home to over half of these plant and animal species. If the rainforests disappear, many of these species will become extinct. This means many species will vanish before we ever discover them. Some environmentalists estimate that rainforest species are disappearing at the rate of 137 species per day. This statistic accompanies another that is equally disturbing: an area of tropical forest equivalent to the size of Austria is cleared away each year.
Is it possible to reverse the devastating effects of deforestation? Many experts think so, but it will require international laws to protect the remaining forests. It will also require a campaign to increase awareness of the problem, and a willingness to practice “green” consumerism.