South America, the fourth-largest continent, extends from the Gulf of Darién in the northwest to the Tierra del Fuego archipelago in the south.
South America’s physical geography, environment and resources, and human geography can be considered separately.
South America has diverse agricultural products, vast mineral wealth, and plentiful freshwater. It also has rich fisheries and ports on three bodies of water: the Caribbean Sea, Atlantic Ocean, and Pacific Ocean. The
continent
’s economy is centered on the export of natural resources.
Climate and Agriculture
South America extends from a broad equatorial zone in the north to a narrow sub-Arctic zone in the south. It can be divided into four climatic regions: tropical, temperate, arid, and cold.
Tropical
climates
—which include both
tropical
rainy and tropical wet and dry climates—cover more than half of the
continent
.
Tropical
rainy conditions occur in the Amazon River basin, the northeastern coast, and the Pacific
coast
of Colombia. The regions’ average daily temperature is 30 degrees Celsius (86 degrees Fahrenheit) with very little temperature variation throughout the year. While average annual rainfall is 262 centimeters (103 inches), some areas receive an extreme amount of precipitation; the Chocó region of Colombia, for example, receives m
ore
than 800 centimeters (315 inches) of rain every year.
Tropical
wet and dry conditions occur in the Orinoco River basin, the Brazilian Highlands, and in a western section of Ecuador. Temperatures are similar to
tropical
rainy, but have a greater daily range. There is also less
precipitation
and a prolonged dry season.
Many crops thrive in the
tropical
climates
of South America. Cashews and Brazil nuts are cultivated. Fruits such as avocado, pineapple, papaya, and guava are also native to
tropical
South America.
Two very im
portant
cash
crops
are coffee and cacao, which is the source of cocoa, the base ingredient in chocolate. Brazil is the world’s largest
ex
porter
of coffee, and it used to be one of the largest
ex
porters
of cacao. In 2000, a fungus spread throughout many of South America’s cacao plantations, devastating the economies of the region and driving up the price of chocolate. The chocolate industries of Brazil, Venezuela, and Ecuador are slowly recovering, but most of the world’s cacao now comes from countries in
tropical
Africa.
The
continent
’s
temperate
climates
are located south of the Tropic of Capricorn and in the mid-level elevations of the Andes mountains.
Temperate
climates
have a greater temperature range and lower winter temperatures than
tropical
climates
.
South America’s
temperate
climates
are home to a number of industrial
crops
and livestock. Corn is produced throughout the
temperate
climates
, and soybeans have become an increasingly lucrative
crop
in the Pampas.
The
Pampas
’ vast, high-quality pastures are also the center of South America’s huge ranching industry. Brazil is the world’s third-largest beef
ex
porter
(behind only Australia and the United States). Argentina is also an im
portant
beef
ex
porter
.
Arid
climates
are found in deserts,
coastal
areas, and interior regions throughout South America. Some of these
climates
are extremely cold, while others are extremely hot—but they all receive very little
precipitation
. This makes agricultural production difficult. However, heavily irrigated
crops
, such as rice and cotton, are grown in
desert
oases.
Cold
climates
occur in the southern ends of Argentina and Chile and the highest elevations of the Andes. Cold
climates
have an average annual temperature of below 10 degrees Celsius (50 degrees Fahrenheit). These
climates
are characterized by long
dry seasons
and high winds.
While these cold
climates
limit
crop
production, they are also home to thousands of native potato species and the native quinoa plant—a grain-like
crop
grown for its edible seeds. Potatoes and
quinoa
are starchy food staples of the Andean diet. Potatoes are now one of the biggest
crops
in the world. Ninety-nine percent of the potatoes grown throughout the world can be traced to a single species that was originally
cultivated
in the Chiloé Archipelago m
ore
than 10,000 years ago.
In addition to potatoes and
quinoa
, grazing animals such as sheep, llamas, alpacas, and vicuñas also thrive in cold
climates
. These animals are bred for their meat and wool, which is used in high-quality textiles
ex
ported
throughout the world.
Forestry and Fishing
F
orestry
is the management of trees and other vegetation in f
orests
. It is a major economic activity for
tropical
South America, especially the Amazon River basin. Many high-value tree species, such as mahogany and rosewood, are native to the rain f
orest
. Lumber from these trees is
ex
ported
to f
oreign
markets for use in cabinets and floors. Some countries have tree plantations. Chile, for example, is an im
portant
ex
porter
of wood chips, plywood, and paper pulp.
Lower-grade woods are im
portant
to the construction market in South America. The most familiar of these less-expensive woods is eucalyptus. Eucalyptus is not native to South America, but it grows at an incredibly quick rate. Eucalyptus is used as both a building material and as fuel in low-income communities throughout South America.
Marine fisheries are the most im
portant
economic activity along South America’s Pacific
coast
, although overfishing has depleted many fish populations. The cold Peru Current brings nutrient-rich waters to the
coast
, creating a fishery with everything from whales to shrimp. Peru and Chile’s abundant anchovy catches are processed into fishmeal, an ingredient used in animal feed and fertilizer. Chile is a global leader in farm-raised salmon and trout, while Ecuador is an im
portant
shrimp
ex
porter
.
Mining and Drilling
The
mining
industry
is one of South America’s most im
portant
economic engines. The
continent
contains about one-fifth of the world’s iron
ore
reserves.
Iron
and steel (an
iron
product) are used in
construction
and machinery throughout the world.
M
ore
than one-quarter of the world’s known copper reserves are in South America, mostly in Peru and Chile. Valued at $26.9 billion in 2009,
copper
accounts for nearly one-third of the
ex
ports
of Chile, the world’s largest
copper
ex
porter
.
Copper
is used in electrical wiring and equipment because it is a good conductor of heat and is resistant to corrosion.
Other im
portant
metal deposits include tin, used to solder metallic surfaces; lead, used in
construction
, batteries, and bullets; and zinc, used as an anti-
corrosion
agent. Brazil, Peru, and Bolivia are major producers of tin. Lead and zinc deposits are found primarily in higher elevations of Peru, Bolivia, southern Brazil, and northern Argentina.
South America is home to some deposits of oil and natural gas, which are drilled for energy and
fuel
.
Oil
and gas extraction is the dominant
industry
of Venezuela, with major deposits found around Lake Maracaibo and the El Tigre region. The
oil
sector accounts for about one-third of Venezuela’s total gross domestic product (GDP).
The Built Environment
South America’s economic growth over the last half-century has prompted its cities to expand rapidly. These cities, however, often suffer from inefficient transportation and utility systems, pollution, and unregulated residential growth.
São Paulo, Brazil, is an industrial powerhouse and the largest city in the Southern Hemisphere, with a population of m
ore
than 11 million. The
city
lies at the center of the São Paulo metropolitan area (SPMA), which has an estimated 19,889,559 residents and covers m
ore
than 7,743 square kilometers (3,067 square miles). The SPMA is defined as a “megalopolis” because it covers a vast area and incorporates several distinct cities.
São Paulo’s growth mostly comes from the coffee boom that hit the
city
in the 1880s. Immigrants from Europe and Japan came to the
city
to work in the coffee trade. Today, São Paulo produces about half of Brazil’s industrial goods and is the center of South American manufacturing.
São Paulo’s economic op
portunities
have attracted many poor migrants. This flood of immigration has spurred the creation of massive shantytowns, called favelas. In São Paulo, there are m
ore
than 600
favelas
.
Favelas
are often removed from the
city
center and disconnected from basic
city
services, such as water, sewage, and electricity.
The drug trade, mostly cocaine, is also centered in
favelas
. Drug trafficking has become a major economic
industry
in South America, providing hundreds of millions of dollars to drug organizations, known as cartels. The farmers who produce raw materials for the drug trade rarely benefit as much as the
cartels
that deliver the drugs to an international market. Drug
cartels
have become a serious security threat to South American governments, especially in Colombia and Brazil.
Lima, Peru, is the second largest
desert
city
in the world, after Cairo, Egypt. The Lima metropolitan area has a population of almost 9 million people and accounts for about one-fourth of Peru’s total population. Lima is known as the Gastronomical Capital of the Americas for the number and diversity of local dishes. These dishes bring together the
city
’s roots as a Spanish colonial center and the influences of both international
immigrants
(African, Chinese, Japanese) and local migrants (Andean, Amazonian).
Lima has the largest
ex
port
industry
in South America. Lima and the nearby
port
city
of Callao are also among the most im
portant
fish trade centers in South America. Lima and Callao have regular, efficient maritime routes to
coastal
Asia.
Much like São Paulo, Lima’s large size causes certain infrastructure problems. Heavy traffic congestion is an effect of Lima’s indirect street and highway network, and unreliable public buses. These older buses are often much smaller and m
ore
polluting than new buses. In order to reduce traffic and
pollution
, Lima is in the process of constructing an above-ground subway-type system.
South America is home to a number of engineering marvels, most of which are connected to managing the
continent
’s
natural
resources
. The Itaipu Dam, completed in 1984, spans the Paraná River at the Brazil-Paraguay border. The
dam
generates m
ore
hydroelectric power than any other
dam
in the world. (China's Three Gorges
Dam
is capable of producing m
ore
, however.) In 2008, the
dam
generated 94.68 billion kilowatt-hours, which supplied 90 percent of Paraguay’s energy and 19 percent of Brazil’s. In 1994, the American Society of Civil Engineers elected the Itaipu
Dam
as one of the Seven Wonders of the Modern World.
South America has some of the largest
mining
operations in the world. The Chuquicamata mine in northern Chile is considered the world’s largest open-pit
copper
mine. It is 4.3 kilometers (2.7 miles) long, 3 kilometers (1.8 miles) wide and m
ore
than 847 meters (2,780 feet) deep. The mine produces m
ore
than one-fourth of Chile’s
copper
. Its smelter (which extracts the
copper
from rock
ore
) and refinery (which purifies the extracted
copper
) are also among the largest in the world.