1

Chapter 9-South America

Geography Matters...

South America is a land of beautiful natural wonders, including the vast Amazon rain forest. However, not all of South America is a lush jungle paradise. The region also includes snow-covered mountains and boasts the world’s driest place—the Atacama Desert.

South America is diverse in culture as well as in landscape. The people of this subregion reflect a unique blend of indigenous and colonial heritage, the result of centuries of migration, trade, and conquest.

LESSON 1-Physical Geography of South AmericaESSENTIAL QUESTION • How do physical systems and human systems shape a place? The diverse landscapes of South America are very different from what we know in the United States. They have led to the people in South America developing very different lifestyles that are adapted to their physical environment.  

Landforms  

How has South America’s rugged landscape both attracted and isolated people? 

The Isthmus of Panama connects North America to South America. The subregion of South America spans 4,700 miles (7,564 km) from north to south, passing through the Equator near its widest point of 3,300 miles (5,311 km). Like Central America and Mexico, the most characteristic of South America’s many landforms are its mountains. The Andes are the world’s longest mountain chain. Some peaks in the Andes rise more than 20,000 feet (6,096 m) above sea level. The Andes consist of cordilleras, groups of several mountain ranges that run parallel to one another. Although known by different names, they are an extension of the Rocky Mountains that run from Canada south through the western United States and into Mexico and Central America. Because the cordilleras have established natural barriers between surrounding areas, many indigenous communities developed as isolated groups. As a result, some mountain villages exhibit centuries-old social customs.The Andes encircle the altiplano, which means “high plain.” The altiplano is an area that includes southeastern Peru and western Bolivia. It is the second-largest mountain plateau in the world.

In southern Argentina, hills and flatlands form the plateau of Patagonia. The presence of the Andes to the west produces a rain shadow that causes Patagonia to be dry, barren, and windy. The Patagonian region also extends across the Andes to southern Chile. Patagonia boasts dramatic valleys, glaciers, and fjords. The rugged Andes and Patagonia’s landscape are a result of its location along the Ring of Fire.

Heavy tectonic activity in the subregion changes and reshapes the landscape. But despite the threats of natural disasters, people have chosen to settle in the Andean highlands for thousands of years. The climates are cooler, the volcanic soil is good for agriculture, and natural resources are concentrated here.

In contrast to the high peaks of the western Andes, eastern South America is defined by broad

2

plateaus and valleys. The Amazon Basin, located along the eastern base of the Andes, is the lowlands area drained by the Amazon River. Just south is the Mato Grosso Plateau, a sparsely populated plateau of forests and grasslands extending across Brazil, Bolivia, and Peru. Farther east are the Brazilian Highlands, a vast area spanning several climate and vegetation zones. Warm climates and open spaces make the Brazilian Highlands good for raising livestock. The Eastern Highlands plunge to the Atlantic Ocean, forming a steep slope called an escarpment. This escarpment presents obstacles for inland development. As a result, most of Brazil’s population lives along the coast.Narrow coastal lowlands hem the Atlantic and Pacific coasts of South America. South America’s inland grasslands—the llanos  (LAH•nohs) of Colombia and Venezuela and the pampas of Argentina and Uruguay—provide grazing for cattle. Ranchers on large estates employ cowhands, called llaneros or gauchos, to drive herds across the rolling plains. Known for its fertile soil, the pampas are one of the world’s breadbaskets, producing wheat and corn.Explaining What features of South America’s landscape have hindered or encouraged development?Water Systems 

How are South America’s rivers important for economic development? 

Waterways are important for the subregion’s economic development because they provide ways to transport goods and people within and between the countries of South America. As the Western Hemisphere’s longest river and the world’s second longest, the Amazon River flows about 4,000 miles (6,400 km) through the heart of South America. It begins in the headwaters of the Peruvian Andes, flows across the lowlands of the Amazon Basin in the interior of Brazil, and drains into the Atlantic Ocean. Hundreds of smaller rivers join the Amazon as it flows from the Andes to the Atlantic Ocean. Together these rivers form the Amazon Basin. The basin drains an area of more than 2 million square miles (5.2 million sq. km).

The Paraná, Paraguay, and Uruguay Rivers form the second-largest river system in Latin America, draining the rainy eastern half of South America. These rivers flow through the Pantanal, one of the world’s largest tropical wetlands. After coursing through inland areas, the rivers flow into a broad estuary where the ocean tide meets a river current. This estuary, the Río de la Plata, or “River of Silver,” flows into the Atlantic Ocean.

Though Latin America has few large lakes, some of its largest lakes are located in South America. Lake Maracaibo (mah•rah•KY•boh) in Venezuela and Lake Titicaca (tee•tee•KAH•kah), which run through Bolivia and Peru, are South America’s largest lakes. Lake Titicaca is also the world’s highest large lake.

Identifying Which rivers drain the eastern part of South America?Climate, Biomes, and Resources 

How does climate affect human activities in South America? 

Diverse climates make South America a region of astonishing contrasts. Steamy rain forests, arid deserts, grassy plains, and sandy beaches can all be found in the subregion. The dense, nearly impenetrable vegetation of South America’s tropical rain forests represents a tremendous resource and supports many communities.

3

Climate Regions and Biomes 

The vertical climate zones found in the highland areas of Central America and Mexico also exist in the highlands of South America. The Andes are distinct not only because of their dramatic height, but also because they have such cold climates despite their proximity to the otherwise tropical equatorial zone. The range in elevation has produced a wide variety of climate and ecological zones.

The temperate climate of the tierra templada is found in areas of Peru, Brazil, and Colombia. Many Andean communities are located in the tierra fría. People in the highlands subsist on potato, barley, and quinoa crops that grow well in this colder climate. South America’s colonial cities in Peru, Bolivia, and Colombia were developed over historical indigenous cities at high altitudes to extract valuable mineral resources found in the Andes. Consequently, several South American capitals are located in the tierra fría zone. The tierra helada and the puna, the highest vertical climate zones located above the tree line, are zones of permanent snow and ice on the peaks of the Andes.

The El Niño phenomenon also affects climate in South America. El Niño creates unusually warm ocean conditions on the west coast that extend as far north as Ecuador and as far south as Chile. As in Central America and the Caribbean, El Niño can have negative effects on coastal weather, fishing, and agriculture.

Tropical wet (rain forest) and tropical wet/dry (savanna) are the predominant climates of eastern South America, which is home to the Amazon rain forest, the world’s largest rain forest. It is located primarily in Brazil but also extends into Peru, Colombia, Venezuela, Ecuador, Bolivia, Guyana, Suriname, and French Guiana. The Amazon shelters more species of plants and animals per square mile than anywhere else on Earth. It covers one-third of South America and is the world’s wettest tropical plain. Heavy rains drench the densely forested lowlands.

A tropical wet/dry climate is typical of north-central South America. These areas have high temperatures and abundant rainfall, but also experience an extended dry season. In many tropical wet/dry areas, grasslands flourish. Some of these grasslands, such as the llanos of Colombia and Venezuela, are covered with scattered trees and are considered transition zones between grasslands and forests. A humid subtropical climate exists in much of southeastern South America. Winters here are short with cool to mild temperatures. Summers are long, hot, and humid. Rainfall is generally uniform throughout the year, but it can be heavier during the summer.

Much of the inland parts of Peru, Bolivia, and Chile experience an arid climate. In these areas, cold air and high elevations result in very little precipitation. Shifting winds and the rain shadow effect of the Andes produce aridity in the southeastern part of Argentina. The low vegetation here is adapted to the low moisture conditions. The cold, oceanic Peru Current creates dry coastal deserts along the Pacific coast of Chile and Peru. These desert areas are called the Atacama. It is so arid that in some places no rainfall has ever been recorded. A dense fog known as camanchaca is the only appreciable source of precipitation.

Natural Resources  

South American countries are among the world’s leading producers of energy resources. Energy resources have supported major growth in economies such as that of Venezuela, which holds most of the subregion’s oil reserves. Because of South America’s substantial natural resources

4

and active tectonic plates that allow for oil extraction, countries continue to search for additional, yet untapped oil reserves.

South America also has an abundance of mineral resources. For example, the foothills along Venezuela’s Orinoco River contain large amounts of gold, and Peru is known for silver. Mines in Colombia have been producing the world’s finest emeralds for more than 1,000 years. South America’s non-precious minerals also have significant economic value. Chile is the world’s largest exporter of copper. Peru and Chile together hold almost one-fourth of the world’s known copper reserves.

Countries in South America do not have equal access to the continent’s natural resources. The size of Venezuela’s oil reserves in comparison to the rest of the subregion’s countries is a clear example of this unbalanced distribution of energy resources. The physical geography within and surrounding each country largely dictates its access to natural resources. Alongside political borders dictated by physical geography, distribution of natural resources within South America was a decisive factor in defining countries’ political borders. Extraction of resources also relates to a country’s infrastructure, level of economic development, and relationships between people and their government. Countries with low capital, social and political divisions, and lack of advanced technology for extracting resources have been at a disadvantage in comparison to countries that can cope with such factors.

Identifying Name three predominant climates in South America and describe their locations.

LESSON 2-Human Geography of South AmericaESSENTIAL QUESTION • How do physical systems and human systems shape a place? The society and governments of South America have been shaped by the subregion’s rich history of indigenous peoples and their interactions with Europeans, Africans, and Asians. The modern economic geography—based on agricultural practices, the continent’s natural resources, and industrial development—has resulted in an imbalance in overall wealth and development. 

History and Government 

How have indigenous peoples and Europeans contributed to the creation of modern governments in South America? 

South America’s diverse population is the result of centuries of blending among hundreds of indigenous groups, Europeans, Africans, and Asians. Some areas in South America are a microcosm of these diverse cultures. In other areas—many of them remote and isolated—indigenous peoples live much as their ancestors did hundreds of years ago, virtually untouched by the influence of other cultures or modern technology.

Early Cultures and European Conquest 

Before the Inca established their empire in the Andes, other early indigenous groups—such as the Moche, Mapuche, and Aymara—developed societies that were based primarily on agriculture. The Inca later established a highly developed civilization in the area. At its height, the Inca Empire stretched from present-day Ecuador to central Chile.

5

The Inca were skilled engineers. They built temples and fortresses and laid out a network of roads that crossed mountain passes and penetrated forests. Inca farmers cut terraces into the slopes of the Andes and built irrigation systems. Machu Picchu, Peru’s most well-known archaeological site, is a grand display of Inca engineering that is remarkably preserved. With no Inca written language, knowledge was passed on to each generation through storytelling. The Inca used quipus (KEE•poos) to account for financial and historical records.

Silver and gold were important resources in the Inca culture. The precious metals and the wealth of farmers of the Inca Empire attracted Spanish conquistadors to Peru. After defeating the Inca army and its rulers, they looted the empire’s capital and network of cities. The Inca connected their vast empire with a network of roads that extended throughout the empire. This allowed the Spanish conquerors to move quickly through the region. Spanish conquistadors expanded into Colombia, Argentina, and Chile. The Portuguese settled on the coast of Brazil, and the British, French, and Dutch later settled in parts of northern South America. The effects of epidemics caused by diseases introduced by the Europeans and the hardships of intensive labor on colonial plantations drastically reduced indigenous populations. To meet the resulting labor shortage, European colonists imported enslaved Africans.

Independence and Movements for Change 

In the 1800s, independence movements arose in South America. These were inspired by the French and American Revolutions, as well as by the struggles for independence in Mexico and the Caribbean. By the mid-1800s, led by revolutionaries such as Simón Bolívar of Venezuela and José de San Martín of Argentina, most South American countries had won independence.

The postcolonial period was politically and economically unstable for most of the newly independent countries. They lacked a tradition of self-government. Power remained in the hands of the wealthy and elite classes of residents, despite written constitutions. With military backing, caudillos, or dictators, throughout South America seized power in the nineteenth century. Caudillos often gained power illegally and with much bloodshed among civilians.

Dictatorships have given way to democratically elected governments across South America. Today, however, these countries are struggling with many issues. These include political corruption and violence, wide gaps between the rich and poor, unemployment, and protecting the rights of indigenous groups.

Identifying What early indigenous civilization dominated much of western South America?Population Patterns 

How has South America’s physical geography influenced its population patterns? 

South America is the world’s fourth-largest continent. The continent’s 12 countries are home to nearly 400 million people. Like much of the rest of the developing world, population growth is steady, and so is the migration of people into large, urban areas.

South America’s once high rate of population growth is beginning to slow. Urban populations now include fewer children as well as women and men with increased levels of education. Most people live on or near the coasts and along major rivers of the continent. These coastal regions offer favorable climates, fertile land, and access to transportation. The rain forests, deserts, and mountainous areas of South America's interior have discouraged human settlement.

6

South American countries tend to have low population densities. Ecuador, the most densely populated country in South America, has an average of 132 people per square mile (51 people per sq. km). Brazil has a population of nearly 200 million. However, because Brazil has about 3.2 million square miles (8.4 million sq. km), its average population density is about 60 people per square mile (23 people per sq. km). Despite population densities that are lower overall than other world regions, much of the economic and structural development is concentrated in major cities. Today about 80 percent of the subregion’s population lives in urban areas.

In highly populated urban areas such as São Paulo, Buenos Aires, and Bogotá, finding employment and suitable living conditions is difficult for migrants arriving in the city. Rural-to-urban migrants seek higher wages, better living conditions, and sometimes an escape from the violence of drug cartels or criminal groups. Countries across the region are experiencing brain drain to North America and Europe as people search for a better life.

Explaining Why do most South Americans live along the continent’s coasts?Society and Culture Today 

Why is South America one of the world’s most culturally diverse areas? 

South America is home to an ethnically diverse population. Today many indigenous cultural groups inhabit the subregion, especially in rural or less populated areas. Most indigenous groups—of which there are more than 350—live in the Andes region of Ecuador, Peru, and Bolivia.

The Spanish and Portuguese were the first Europeans in South America. Enslaved Africans were later brought as laborers. After South American countries gained their independence, other European groups—French, Dutch, Italians, and Germans—moved to South America. In fact, Argentina’s population is 97 percent European, as the majority of Argentines are descendants of Spanish and Italian immigrants. Towns in the lakes region of southern Chile exhibit architecture, cuisine, and traditions influenced by its German population.

Immigrants from Asia also arrived in South America. In Guyana, almost half of the population is of South Asian descent. People of Chinese descent have immigrated to Peru. Many people of Japanese descent live in Brazil, Argentina, and Peru. Spanish, Portuguese, Dutch, French, and English are each spoken in different parts of South America. In countries with South Asian populations, such as in Guyana and Suriname, people also speak Urdu, Javanese, and Caribbean Hindustani, a dialect of Hindi. As a result, people in South America are often bilingual. During the colonial period, some European languages blended with indigenous languages to form completely new languages.

The majority of South Americans are Roman Catholic. Carnival is celebrated in the week before the Roman Catholic observance of Lent, a 40-day period of fasting and prayer before Easter. People from around the world come to Rio de Janeiro to participate in Carnival celebrations. In addition, tens of millions of people practice syncretism, a combination of mixed religions, such as Macumba and Candomblé, which combine West African religions with Roman Catholicism. Other minority religions include Protestant Christianity, Hinduism, Buddhism, Shinto, Islam, Judaism, and Eastern Orthodox Christianity.

Education varies greatly throughout South America. Many countries support public education through high school, and literacy rates have risen steadily. Public universities provide higher education at little or no cost to students in many countries. Many children leave school before

7

completion, however, to help support the family by selling goods in markets or engaging in household or farming duties.

In countries with stable economies and high standards of living, people have access to better health care and live longer, healthier lives. This results in a situation of uneven development among countries. The health of a country’s people is linked to poverty, lack of sanitation, infectious diseases, and malnutrition. These conditions persist in rural areas and especially in the slums on the outskirts of cities where millions of people live in overcrowded conditions.

Family and the Status of Women 

In urban upper and middle classes, the family unit is likely to consist of a nuclear household—father, mother, and dependent children—rather than an extended family. Loyalty and responsibility toward the extended family, however, remain very strong. The compadre relationship, in which parents and godparents share in the upbringing of a child, is valued in parts of Latin America. However, changes brought about by urban society have diminished its overall importance.

The elevation of women’s rights has grown as countries have established more stable governments and economies in the past few decades. The result is an increasing proportion of women entering the workforce. Work codes in Chile and Colombia provide benefits for pregnant employees, and women’s earnings are increasing in comparison to men’s wages. Although women can still face discrimination and mistreatment, there are signs of change. Some countries now provide shelters for abused women and enforce stricter penalties for offenders.

The Arts 

Indigenous arts survive in many different forms. The massive buildings of the ancient Inca at Cuzco and Machu Picchu reveal a mastery of stone and engineering that are still studied today for their ingenuity. Traditional arts and crafts dating from before the arrival of the Europeans—such as weaving, ceramics, and metal working—have been passed from generation to generation.

Music also has ancient ties. Panpipes are one of the most common pre-Columbian musical instruments from the Andean region. Musical traditions later mixed Native American, African, and European influences to create unique styles. The Brazilian samba, Chilean cumbia, and the Argentine tango complement the Cuban salsa and Dominican merengue to exemplify the diversity of music developed from a mixture of cultural and geographical roots.

Specifying How has South America’s role as a cultural melting pot contributed to its unique cultural elements?Economic Activities 

How have South America’s abundant natural resources contributed to its economic development? 

Several countries in the region have combined their abundance of natural resources with current changes in government and improved economic conditions. Argentina is not only rich in natural resources, but also has a highly literate population and a diversified economic base that have helped to fuel a strong expansion in its economy. Brazil, the largest country in South America,

8

has been undergoing continuous growth and development since 1970. Taking advantage of its natural resources, Brazil has become a powerful country in economic terms. Chile has established free-trade agreements with the United States, Turkey, Australia, and other countries to enhance its economic activities.

Resources and Industry 

Land and water use in South America closely follow physical geography. Forestry prevails in the Amazon Basin. Ranching is widespread in the grasslands of the south. Herding llamas and alpacas occurs in the high Andean regions. Fishing occurs in major lakes, rivers, and along coastlines. Agriculture remains highly important in South America. More than 20 percent of the subregion’s workforce is employed in the primary sector that includes farming, ranching, and fishing. As in other subregions of Latin America (Mexico and Central America and the Caribbean), the legacy of the hacienda system still exists in South America. Larger commercial and smaller subsistence agriculture exist side by side.

Agriculture dominates much of east-central Brazil and the nearby areas of Paraguay, Uruguay, and Argentina. South America’s contribution to agricultural global trade includes grains, soybeans, coffee, cocoa, citrus, cattle, sugarcane, tobacco, and cotton. In fact, Brazil is the world’s largest exporter of coffee. Brazil and Paraguay also cultivate today’s fastest-growing crop in the global economy: soybeans. Paraguay is the sixth-largest producer of soybeans in the world.

Additionally, the coca plant thrives in the northwestern parts of South America. Coca use is popular among Bolivia and Peru’s working class for its effects as a legal stimulant and appetite suppressant. Yet coca’s derivative can also be used to make the illegal drug cocaine. Peru, Bolivia, and Colombia have nonetheless legalized coca farming. They did so because, sold in its legal form, it is a large source of profit for these countries.

Natural resources include timber, gold, silver, copper, iron ore, and tin. South America contains about one-fifth of the world’s iron ore, which is used for steel making and machine building. Many countries are heavily dependent on exporting their natural resources. Energy resources include petroleum and natural gas. Venezuela, Ecuador, and Argentina are leading exporters.

Manufacturing is growing rapidly, but the region's geography varies greatly. Most manufacturing is concentrated in urban areas, especially the primate cities. Because the largest cities lie mainly along the coasts where transportation is the best, the vast interior of South America has few manufacturing plants.

The major road systems in South America include the Pan-American Highway that stretches through Chile as it links many cities north to south, and the Trans-Andean Highway that links cities in Chile and Argentina east and west. The Trans-Amazonian Highway was built by Brazil to access the Amazon rain forest for developing timber and mineral resources. The Transoceanic Highway was designed to link the Amazon River ports with Peru’s ports on the Pacific to transport agricultural products to the global markets in Asia and Europe. Argentina and Brazil have well-developed rail systems, which are important modes of transportation along with the inland waterways. All South American capital cities and major cities have domestic and international airports.

Economic Integration 

9

The increased global demand for raw natural resources and manufacturing has had an impact on the overall economic growth in the region’s countries. The economic growth has affected Brazil, Chile, and Argentina more than other countries. Ecuador, Peru, Venezuela, and Bolivia have struggled to modernize their economies and improve standards of living. For example, Bolivia is one of South America’s most impoverished and least developed countries. Political reforms in the 1990s stimulated economic growth, but Bolivia continues to struggle to improve conditions for its people.

The separatism that characterized South American countries in the past is giving way to new trade partnerships and cooperation on infrastructure that are mutually beneficial. In South America’s current economy, investments flow more freely from one country to another. For example, Colombia has taken advantage of its more stable economy by promoting free-trade agreements with other countries. Colombia implemented the U.S.-Colombia Free Trade Agreement with the United States in 2012. Colombia is negotiating free-trade agreements with other Latin American countries, such as Chile and Mexico, as well as with countries outside South America. Additionally, Colombia has 59 bilateral or regional trade agreements—more than any other country.

Economic growth has been steady and strong across the region and has permitted countries to pay their foreign debt. If the economy does not grow, then the debt payments reduce the amount of money available to the government for essential services such as roads, water, flood control, and health care. Consistent, stable economic policies adopted by some South American countries in recent decades have contributed to steady economic growth and improved standards of living for people.

Inferring What is the benefit of cooperation between countries in South America?

LESSON 3People and Their Environment: South AmericaESSENTIAL QUESTION • How do physical systems and human systems shape a place? The use of natural resources for economic advancement has benefited the livelihood and stability of many South American countries. It has also caused damage to the continent’s natural environment and dramatic changes to its biodiversity.  

Managing Resources  

How has the management of forest and agricultural resources impacted the environment in South America? 

South America is home to some of the largest reserves of forest and agricultural resources in the world. Countries are taking advantage of such resources to improve their economies and overall wealth. Extensive exploitation of resources comes at a cost, however. Issues such as deforestation, soil erosion, desertification, and pollution have been significant problems for all countries in South America.

Like the rain forests of Costa Rica and Panama, the rain forests of South America are threatened by intensive human activity. Rain forests harbor at least half of all animal and plant species on Earth. Deforestation is occurring at a rapid rate in the Amazon rain forest. This has reduced the

10

diversity of plants and animals there. Brazil has the world’s largest remaining expanses of tropical rain forest, but almost 20 percent of the Amazon rain forest has already been destroyed. The loss of biodiversity is also occurring in Brazil’s lesser known Atlantic Forest, one of Earth’s richest and most threatened habitats. The Atlantic Forest now covers less than 10 percent of its original area.

Soil erosion in South America has diminished the ability of soils to produce food and vegetation. Intensive farming, construction, logging, fires, and overgrazing all increase the rate of soil erosion. Certain soil types in South America—such as the volcanic soils and oxisols found in the humid tropical lowlands—are especially vulnerable to erosion. The oxisols, sometimes known as laterites, can degrade into a baked clay-like form when too much of the natural vegetation cover is removed. The removal of topsoil occurs as a result of intensive agriculture, especially on landscapes that have been cultivated for long periods of time.

Large-scale agriculture also worsens the progression of soil erosion. Monoculture, the growth of a single type of crop on agricultural or forested land, depletes the soil of its nutrients. It disrupts the natural cycle of growth and breakdown of plants, animals, and bacteria. Without these natural processes, soil cannot rebuild its nutrients. Vast monoculture soybean crops in Brazil, for example, are quickly depleting soil fertility.

The general process of soil erosion summarizes the progression and effects of desertification. Because ecosystems are dynamic and respond to changes in environmental conditions, processes such as soil erosion and desertification are drastically changing the landscapes and ecology of South America’s extensive croplands and grazing lands. The primary cause of desertification is not drought, but rather mismanagement of land by human activities such as overgrazing of livestock and deforestation. Rain-fed crops in drylands, such as wheat and corn, can lead to desertification. After wheat and corn are harvested, the lands left uncovered between planting seasons become vulnerable to erosion by climatic forces such as wind and rain. Wind can create heavy dust storms by sweeping up uncovered topsoil. This deprives extensive land areas of the nutrients from organic matter contained by topsoil. Though rainfall in drylands is uncommon, heavy downpours do occur. This results in otherwise fertile and nutrient-rich topsoil being washed away. For large-scale irrigation on drylands, salinization is also a significant issue. Once fields are irrigated, water dries quickly and leaves behind salt. These salts collect and reduce the ability of plant roots to absorb water and grow.

Desertification also occurs in rangelands, which support a large population of grazing animals such as cattle and sheep. Grazing livestock consume plants almost to ground level. This weakens plants’ ability to grow.

The movement of herds of livestock also destroys plant roots that bind the soil. When rain comes, water often washes away unprotected topsoil. This process of desertification in rangelands is a serious issue in places with a strong livestock industry: Argentina, Uruguay, Brazil, and Paraguay.

Summarizing How does overgrazing worsen processes of desertification?

11

Save

Human Impact 

Why does urban growth and industrialization create environmental problems in South America?

Large-scale economic production and urban growth have created multiple forms of environmental pollution. São Paulo, Brazil, is an example of the significant amount and effect of multiple sources of urban pollution. With a population of some 19 million, São Paulo is the largest city in the Southern Hemisphere. São Paulo has attracted millions of poor migrants. Many have settled in favelas, or slums on the outskirts of the city consisting of crudely built shacks. These favelas are disconnected from the services of the established city. They are thus particularly problematic as sources of sewage and unrestricted residential growth.

Rapid urban growth also requires cities to find methods for disposing of human waste and sewage. Many urban regions, particularly those in less developed countries, lack the funding and organization to build extensive networks of piped water, drains, and sewage treatment plants. One example is the Bolivian city of El Alto, which is located along the Pallina River that flows into Lake Titicaca. El Alto has seen rapid growth resulting in increased pollution from human waste and sewage. The polluted Pallina River had once been a source of clean water for the people who lived on its banks, but now the waters that flow into Lake Titicaca are contaminated.

Illegal mining has further damaged the natural land and water features of South America. Since 2007, the price of gold has doubled in value. For gold-producing countries such as Peru, the sixth-largest producer in the world, this has presented a potential for immense wealth and economic development. Yet the rise in the value of gold has also encouraged illegal mining activity, especially in countries with an impoverished majority population and ineffective regulatory procedures in government. In Peru, for example, tens of thousands of people have set up camp in the Amazon rain forest in search of vast gold reserves. Alongside individual prospecting, large-scale mining by use of bulldozers and barges has also increased. Rapid deforestation has resulted from rapid migration, makeshift housing, and industrial-scale mining operations. Also, because miners use mercury and other toxic compounds to separate gold from ore, high levels of mercury and cyanide pollution in rivers have been reported.

Though clashes between security forces and miners have created hostility and further chaos, countries affected by illegal mining have made efforts to regulate the vulnerable regions. Colombia is cracking down on illegal mining because anti-government guerrilla groups have been using profits from illegal mining to finance their efforts. Meanwhile, Brazil has employed 8,700 military personnel to fight illegal gold mining along its northern borders.

Specifying What are three sources of pollution in South America?Addressing the Issues 

How are people and governments addressing environmental issues in South America? 

Addressing issues related to human impact on the natural environment is important not only for

12

protecting regional biodiversity, but also for preserving the livelihood of human populations. Many South American countries, such as Uruguay, Paraguay, and Guyana, depend on crops and agriculture as their economic base. These countries are very vulnerable to changing weather patterns and infertile lands.

South American countries that recognize the impact of deforestation are passing laws to protect their lands. For example, in response to the high rate of deforestation in Paraguay, the country’s government passed the Zero Deforestation Law in 2004. This law prohibits forested areas from being converted to landscapes for other uses in the eastern region of Paraguay. The law’s enforcement has dramatically reduced Paraguay’s deforestation rate.

At a local level, farmers can implement management strategies to slow the process of soil erosion. Specifically, soil erosion due to the formation of oxisols can be prevented with careful application and management of lime and fertilizers. Cover crops, which are plants that cover topsoil after crops have been harvested, prevent potential soil erosion from wind and water. At large scales, plant cover can contribute to more regular rainfall patterns, reducing the occurrence of drought and further soil erosion.

Soil conservation efforts will slow land degradation, but restoring soil fertility is much more difficult. On average, a millimeter of soil is generated in about 100 years. Therefore, soil erosion is a more rapid process than soil generation. Once soil has begun to erode, the amount by which it can be restored to fertility depends on how much it has degraded. Lightly degraded soils can be improved by using farm practices. Severely eroded land is generally abandoned because required resources to restore the soil are often too costly. Furthermore, without coordinated prevention efforts among farmers and government, areas of infertile soil will continue to reduce the region’s biodiversity. Land available for food production will also be reduced.

Countries across South America are taking steps to reduce air pollution at the local level by establishing regulations. The results of the regulations can be seen in the reduction of greenhouse gas emissions in the continent’s largest cities. For example, although São Paulo is one of the world’s largest cities, it has much lower levels of carbon dioxide emissions than other large cities. Other large cities in South America also have lower greenhouse gas emissions than might be expected given their high populations.

In order to fix current problems and reduce future ones, South American countries must address the specific factors related to urbanization. The problems include urban sprawl, longer distances that residents travel within cities, increased use of cars, and inefficient public transport systems. Argentina is a global role model for setting voluntary greenhouse gas emissions targets. Furthermore, in 2010 Argentina and Uruguay formed a joint effort to monitor pollution along the Uruguay River, which defines the Argentina-Uruguay border.

Another issue for establishing effective policies is that regulations established by governments or international agreements could restrict countries’ access to natural resources for export production. South American countries that lack the money to invest in alternative export resources are reluctant to establish environmental restrictions. Therefore, to promote the growth of sustainable economies, more developed countries must work closely with less developed countries in South

13

America. Assistance in the area of enforcing and creating policies is of great importance.

Human modifications of the physical environment can have significant global impacts. Therefore, the international community is motivated to work together to find solutions to increasing environmental changes. Despite measures taken to produce effective policies, however, there is a weak foundation of air and water quality management among South American countries. Efforts are focused more on primary metropolitan areas rather than smaller urban regions, which are now among the urban areas of South America with the most rapid growth rates. Environmental awareness and policy making is relatively recent and therefore will require time, resources, and cooperation among the world’s institutions in order to ensure an improved quality of life for South Americans.

Drawing Conclusions Why is it important for countries to work together to create regulations for future environmental use?