Amazon Rain Forest
78
F oc u s O n : Amazon Ra in F or est
F o cus On: Amaz on Rai n F o rest The Continent:
SouTH AMERICA
TROPICAL RAIN FORESTS: FACTS & FIGURES ¢
ropical rain forests cover 6 percent T of Earth’s surface, but are home to half of Earth’s species.
¢
verage monthly temperature A is 68º to 82ºF (20º to 28ºC).
¢
Total annual rainfall averages 5 to 33 feet (1.5 to 10 m).
¢
rees in tropical rain forests T can grow up to 200 feet (60 m) in height.
¢
ost nutrients in tropical rain M forests are stored in the vegetation rather than in the soil, which is very poor.
¢
ome of Earth’s most valuable S woods, such as teak, mahogany, rosewood, and sandalwood, grow in tropical rain forests.
¢
p to 25 percent of all medicines U include products originating in tropical rain forests.
¢
ropical rain forests absorb carbon T dioxide and release oxygen.
¢
eforestation of tropical rain forests D contributes to climate change.
¢
lmost half of all forest loss in the period A 2000–2010 occurred in tropical forests.
¢
razil and Indonesia had the highest net B loss of forest in the 1990s but have significantly reduced their rates of loss.
79
The Continent:
SouTH AMERICA
Amazon Rain Forest
The Amazon rain forest, which covers approximately 2.7 million square miles (7 million sq km), is the world’s largest tropical forest. Located mainly in Brazil, the Amazon rain forest accounts for more than 20 percent of all the world’s tropical forests. Known in Brazil as the selva, the rain forest is a vast storehouse of biological diversity, filled with plants and animals both familiar and exotic. According to estimates, at least half of all terrestrial species are found in tropical forests, but many of these species have not yet been identified. Tropical forests contain many valuable resources, including cacao (chocolate), nuts, spices, rare hardwoods, and plant extracts used to make medicines. Some drugs used in treating cancer and heart disease come from plants found only in tropical forests. But human intervention—logging, mining, and clearing land for crops and grazing—has put tropical forests at Slow-moving, this three-toed sloth spends most of its life in great risk. In Brazil, roads cut into the rain forthe treetops. It is one of the many est have opened the way for settlers, who clear unusual species of animals that away the forest only to discover soil too poor in make their homes in the forests of the Amazon Basin. nutrients to sustain agriculture for more than a few years. Land usually is cleared by a method called slash-and-burn, which contributes to global warming by releasing great amounts of carbon dioxide into the atmosphere.
Dense canopy of the rain forest stands in sharp contrast to the silt-laden waters of one of the Amazon’s many tributaries. Although seemingly endless, the forest in Brazil is decreasing in size due to mining, farming, ranching, and logging.
Slash-and-burn is a method used in the tropics for clearing land for farms. But the soil is poor in nutrients, and good yields are short-lived.
Mining operations, such as this tin mine, remove forests to gain access to mineral deposits.
C a u ses o f D ef o restati o n i n the A ma z o n
Human activity, especially clearing forests to open up land for cattle ranches and subsistence farms, has resulted in serious loss of this valuable ecosystem.
Pgs 70-79 SWA_SA_REL.indd 78-79
3/26/14 2:09 PM
F oc u s O n : Amazon Ra in F or est
F o cus On: Amaz on Rai n F o rest The Continent:
SouTH AMERICA
TROPICAL RAIN FORESTS: FACTS & FIGURES ¢
ropical rain forests cover 6 percent T of Earth’s surface, but are home to half of Earth’s species.
¢
verage monthly temperature A is 68º to 82ºF (20º to 28ºC).
¢
Total annual rainfall averages 5 to 33 feet (1.5 to 10 m).
¢
rees in tropical rain forests T can grow up to 200 feet (60 m) in height.
¢
ost nutrients in tropical rain M forests are stored in the vegetation rather than in the soil, which is very poor.
¢
ome of Earth’s most valuable S woods, such as teak, mahogany, rosewood, and sandalwood, grow in tropical rain forests.
¢
p to 25 percent of all medicines U include products originating in tropical rain forests.
¢
ropical rain forests absorb carbon T dioxide and release oxygen.
¢
eforestation of tropical rain forests D contributes to climate change.
¢
lmost half of all forest loss in the period A 2000–2010 occurred in tropical forests.
¢
razil and Indonesia had the highest net B loss of forest in the 1990s but have significantly reduced their rates of loss.
79
The Continent:
SouTH AMERICA
Amazon Rain Forest
The Amazon rain forest, which covers approximately 2.7 million square miles (7 million sq km), is the world’s largest tropical forest. Located mainly in Brazil, the Amazon rain forest accounts for more than 20 percent of all the world’s tropical forests. Known in Brazil as the selva, the rain forest is a vast storehouse of biological diversity, filled with plants and animals both familiar and exotic. According to estimates, at least half of all terrestrial species are found in tropical forests, but many of these species have not yet been identified. Tropical forests contain many valuable resources, including cacao (chocolate), nuts, spices, rare hardwoods, and plant extracts used to make medicines. Some drugs used in treating cancer and heart disease come from plants found only in tropical forests. But human intervention—logging, mining, and clearing land for crops and grazing—has put tropical forests at Slow-moving, this three-toed sloth spends most of its life in great risk. In Brazil, roads cut into the rain forthe treetops. It is one of the many est have opened the way for settlers, who clear unusual species of animals that away the forest only to discover soil too poor in make their homes in the forests of the Amazon Basin. nutrients to sustain agriculture for more than a few years. Land usually is cleared by a method called slash-and-burn, which contributes to global warming by releasing great amounts of carbon dioxide into the atmosphere.
Dense canopy of the rain forest stands in sharp contrast to the silt-laden waters of one of the Amazon’s many tributaries. Although seemingly endless, the forest in Brazil is decreasing in size due to mining, farming, ranching, and logging.
Slash-and-burn is a method used in the tropics for clearing land for farms. But the soil is poor in nutrients, and good yields are short-lived.
Mining operations, such as this tin mine, remove forests to gain access to mineral deposits.
C a u ses o f D ef o restati o n i n the A ma z o n
Human activity, especially clearing forests to open up land for cattle ranches and subsistence farms, has resulted in serious loss of this valuable ecosystem.
Pgs 70-79 SWA_SA_REL.indd 78-79
3/26/14 2:09 PM
