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Location: Central South America, southwest of Brazil
Geographic coordinates: 17 00 S, 65 00 W
Map references: South America
Area:
total: 1,098,580 sq km
land: 1,084,390 sq km
water: 14,190 sq km
Area - comparative: slightly less than three times the size
of Montana
Land boundaries:
total: 6,743 km
border countries: Argentina 832 km, Brazil 3,400 km, Chile
861 km, Paraguay 750 km, Peru 900 km
Coastline: 0 km (landlocked)
Maritime claims: none (landlocked)
Climate: varies with altitude; humid and tropical to cold
and semiarid
Terrain: rugged Andes Mountains with a highland plateau
(Altiplano), hills, lowland plains of the Amazon Basin
Elevation extremes:
lowest point: Rio Paraguay 90 m
highest point: Nevado Sajama 6,542 m
Natural resources: tin, natural gas, petroleum, zinc, tungsten,
antimony, silver, iron, lead, gold, timber, hydropower
Land use:
arable land: 2%
permanent crops: 0%
permanent pastures: 24%
forests and woodland: 53%
other: 21% (1993 est.)
Irrigated land: 1,750 sq km (1993 est.)
Natural hazards: cold, thin air of high plateau is obstacle
to efficient fuel combustion, as well as to physical activity by
those unaccustomed to it from birth; flooding in the northeast (March-April)
Environment - current issues: the clearing of land for agricultural
purposes and the international demand for tropical timber are contributing
to deforestation; soil erosion from overgrazing and poor cultivation
methods (including slash-and-burn agriculture); desertification;
loss of biodiversity; industrial pollution of water supplies used
for drinking and irrigation
Environment - international agreements:
party to: Biodiversity, Climate Change, Climate Change-Kyoto
Protocol, Desertification, Endangered Species, Hazardous Wastes,
Law of the Sea, Marine Dumping, Nuclear Test Ban, Ship Pollution,
Tropical Timber 83, Tropical Timber 94, Wetlands
signed, but not ratified: Environmental Modification, Marine
Dumping, Marine Life Conservation, Ozone Layer Protection
Geography - note: landlocked; shares control of Lago Titicaca,
world's highest navigable lake (elevation 3,805 m), with Peru
Background: Bolivia, named after independence fighter Simon
BOLIVAR, broke away from Spanish rule in 1825; much of its subsequent
history has consisted of a series of nearly 200 coups and counter-coups.
Comparatively democratic civilian rule was established in the 1980s,
but leaders have faced difficult problems of deep-seated poverty,
social unrest, and drug production.
Current goals include attracting foreign investment, strengthening
the educational system, continuing the privatization program, and
waging an anti-corruption campaign.
Bolivia
GEOGRAPHY
Size: 1,098,581 square kilometers.
Topography: Landlocked. Land is 20 percent arid
or desert, 40 percent rain forest, 25 percent pasture and meadow,
2 percent arable, 2 percent inland water, and 11 percent other,
including negligible percentage irrigated. Divided by two parallel
Andean ranges or cordilleras, on roughly north-south axis, into
three distinct ecozones: vast arid Altiplano plateau between western
range (Cordillera Occidental) and eastern range (Cordillera Occidental),
with Lake Titicaca on northern end; semitropical Yungas and temperate
valleys of Cordillera Oriental; and eastern lowlands (Oriente),
including semiarid Chaco region.
Climate: Tropical with heavy rainfall in northern
lowlands to temperate in highland valleys and harsh, chilly conditions
on windswept Altiplano, where daily temperatures fluctuate sharply.
Uninhabited areas over 5,500 meters high have arctic climate.
Data as of December 1989
Bolivia
GEOGRAPHY
Landlocked Bolivia sits astride the Andes in the west-central part
of the South American continent. With an area of 1,098,581 square
kilometers, the country is about the size of Texas and California
combined, or twice the size of Spain. Bolivia has 6,083 kilometers
of land boundaries, which adjoin five countries. The country is
bounded by Brazil to the north and east, Paraguay to the southeast,
Argentina to the south, Chile to the southwest, and Peru to the
northwest (see fig. 1).
Data as of December 1989
Bolivia
Natural Regions
Stretching in a broad arc across western Bolivia, the Andes define
the country's three geographic zones: the mountains and Altiplano
in the west, the semitropical Yungas and temperate valleys of the
eastern mountain slopes, and the tropical lowlands or plains (llanos)
of the eastern lowlands, or Oriente. The Andes run in two great
parallel ranges or cordilleras. The western range (Cordillera Occidental)
runs along the Peruvian and Chilean borders. The eastern range (Cordillera
Oriental) is a broad and towering system of mountains stretching
from Peru to Argentina. Between the two ranges lies the Altiplano,
a lofty plateau 805 kilometers long and 129 kilometers wide .
Data as of December 1989
Bolivia
Mountains and Altiplano
The Cordillera Occidental is a chain of dormant volcanoes and solfataras,
volcanic vents emitting sulfurous gases. Bolivia's highest peak,
the snowcapped Sajama (6,542 meters), is located here. The entire
cordillera is of volcanic origin and an extension of the volcanic
region found in southern Peru. Most of the northern part of this
range has an elevation of about 4,000 meters; the southern part
is somewhat lower. Rainfall, although scanty everywhere, is greater
in the northern half, where the land is covered with scrub vegetation.
The southern area receives almost no precipitation, and the landscape
consists mostly of barren rocks. All of the Cordillera Occidental
region is sparsely populated, and the south is virtually uninhabited.
The Altiplano, the high plateau between the two cordilleras, comprises
four major basins formed by mountainous spurs that jut eastward
from the Cordillera Occidental about halfway to the Cordillera Oriental.
Along the Altiplano's eastern side is a continuous flat area, which
has served as Bolivia's principal north-south transportation corridor
since colonial times. The entire Altiplano was originally a deep
rift between the cordilleras that gradually filled with highly porous
sedimentary debris washed down from the peaks. This sedimentary
origin explains its gradual slope from north to south; greater rainfall
in the north has washed a larger quantity of debris onto the platform
floor.
The most prominent feature of the Altiplano is the large lake at
its northern end, Lake Titicaca. At 3,810 meters above sea level,
it is the highest navigable body of water in the world. With a surface
area of 9,064 square kilometers, it is larger than Puerto Rico and
is South America's largest lake. Lake Titicaca is also deep, about
370 meters at its maximum, but with an average depth of 215 meters;
its volume of water is large enough to maintain a constant temperature
of 10° C. The lake actually moderates the climate for a considerable
distance around it, making crops of corn and wheat possible in sheltered
areas.
Lake Titicaca drains southward through the slow-moving, reedfilled
Desaguadero River to Lake Poopó. In contrast to the freshwater Lake
Titicaca, Lake Poopó is salty and shallow, with depths seldom more
than four meters. Because it is totally dependent on seasonal rainfall
and the overflow from Lake Titicaca, Lake Poopó's size varies considerably.
Several times in the twentieth century, it nearly dried up when
rainfall was low or the Desaguadero River silted. In years of heavy
rainfall, however, Lake Poopó has overflowed to the west, filling
the Coipasa Saltpan with shallow water.
Rainfall in the Altiplano decreases toward the south, and the scrub
vegetation grows more sparse, eventually giving way to barren rocks
and dry red clay. The land contains several salt flats, the dried
remnants of ancient lakes. The largest of these is the Uyuni Saltpan,
which covers over 9,000 square kilometers. The salt is more than
five meters deep in the center of this flat. In the dry season,
the lake bed can be traversed by heavy trucks. Near the Argentine
border, the floor of the Altiplano rises again, creating hills and
volcanoes that span the gap between the eastern and western cordilleras
of the Andes.
The much older Cordillera Oriental enters Bolivia on the north
side of Lake Titicaca, extends southeastward to approximately 17
south latitude, then broadens and stretches south to the Argentine
border. The northernmost part of the Cordillera Oriental, the Cordillera
Real, is an impressive snow-capped series of granite mountains.
Many of these peaks exceed 6,000 meters, and two--Illimani (6,322
meters), which overlooks the city of La Paz, and Illampu (6,424
meters)--have large glaciers on their upper slopes. South of 17
south latitude, the range changes character. Called the Cordillera
Central here, the land is actually a large block of the earth's
crust that has been lifted and tilted eastward. The western edge
of this block rises in a series of steep cliffs from the Altiplano.
The backbone of the cordillera is a high, rolling plain, with elevations
from 4,200 to 4,400 meters, interspersed with irregularly spaced
high peaks. Too high to be exploited for large-scale commercial
grazing, this area takes its name from the predominant vegetation
type, the puna.
Data as of December 1989
Bolivia
Yungas and Other Valleys
The northeastern flank of the Cordillera Real is known as the Yungas,
from the Aymara word meaning "warm valleys." The steep, almost inaccessible
slopes and peaks of this mainly semitropical valley area northeast
of La Paz offer some of the most spectacular scenery in Bolivia.
Rainfall is heavy, and lush vegetation clings to the sides of narrow
river valleys. The land is among the most fertile in Bolivia, but
poor transportation has hindered its agricultural development. The
government attempted to build a railroad through the Yungas in 1917
to connect La Paz with the eastern lowlands. The railroad was abandoned,
however, after completion of only 150 kilometers.
The eastern slopes of the Cordillera Central descend gradually
in a series of complex north-south ranges and hills. Rivers, draining
to the east, have cut long narrow valleys; these valleys and the
basins between the ranges are favorable areas for crops and settlement.
Rich alluvial soils fill the low areas, but erosion has followed
the removal of vegetation in some places. The valley floors range
from 2,000 to 3,000 meters above sea level, and this lower elevation
means milder temperatures than those of the Altiplano. Two of Bolivia's
most important cities, Sucre and Cochabamba, are located in basins
in this region.
Data as of December 1989
Bolivia
Lowlands
The eastern lowlands include all of Bolivia north and east of the
Andes. Although comprising over two-thirds of the national territory,
the region is sparsely populated and, until recently, has played
a minor role in the economy.
Differences in topography and climate separate the lowlands into
three areas. The flat northern area, made up of Beni and Pando departments
and the northern part of Cochabamba Department, consists of tropical
rain forest. Because much of the topsoil is underlain by clay hardpan,
drainage is poor, and heavy rainfall periodically converts vast
parts of the region to swamp. The central area, comprising the northern
half of Santa Cruz Department, has gently rolling hills and a drier
climate than the north. Forests alternate with savanna, and much
of the land has been cleared for cultivation. Santa Cruz, the largest
city in the lowlands, is located here, as are most of Bolivia's
petroleum and natural gas reserves. The southeastern part of the
lowlands is a continuation of the Chaco of Paraguay. Virtually rainless
for nine months of the year, this area becomes a swamp for the three
months of heavy rains. The extreme variation in rainfall supports
only thorny scrub vegetation and cattle grazing, although recent
discoveries of natural gas and petroleum near the foothills of the
Andes have attracted some settlers to the region.
Most of Bolivia's important rivers are found in the water-rich
northern parts of the lowlands, particularly in the Alto Beni (Upper
Beni), where the land is suitable for crops such as coffee and cacao.
The northern lowlands are drained by wide, slow-moving rivers, the
three largest of which--the Mamoré, Beni, and Madre de Dios--all
flow northward into the Madeira River in Brazil and eventually into
the Amazon. Riverboats along the Beni and the Mamoré carry both
passenger and freight traffic; rapids on the Madeira prevent river
traffic farther into Brazil. Near the Paraguayan border, shallow
sandy streams carry the seasonal runoff into the Pilcomayo or Paraguay
rivers.
Data as of December 1989
Bolivia
Climate
Although Bolivia lies entirely within tropical latitudes, climatic
conditions vary widely from tropical in the lowlands to polar in
the highest parts of the Andes. Temperatures depend primarily on
elevation and show little seasonal variation. In most locations,
rainfall is heaviest during the Southern Hemisphere summer, and
yearly amounts tend to decrease from north to south.
Northern lowland areas have a tropical wet climate with yearround
high temperatures, high humidity, and heavy rainfall. Daytime highs
average more than 30° C all year in most locations. The rain-bearing
northeast trade winds, blowing across the Amazon Basin, bring significant
rainfall amounts. Rain often falls in brief thunderstorms, sometimes
accompanied by strong winds and hail.
Central lowland areas have a tropical wet and dry climate. From
October through April, northeast trade winds predominate, and the
weather is hot, humid, and rainy. From May through September, however,
dry southeast trade winds take control, and precipitation is minimal.
During this season, clear days and cloudless nights allow for higher
daily maximums and lower nightly minimums than occur during the
rainy season. Occasional incursions of strong winds from the south,
called surazos, can reach this region during winter and bring cool
temperatures for several days.
The Chaco has a semitropical, semiarid climate. The northeast trade
winds bring rain and hot humid conditions only from January through
March; the other months are dry with hot days and cool nights. Bolivia's
highest maximum temperature, 47° C, was recorded here. Surazos
also affect the Chaco; their approach is usually signaled by a squall
line.
Temperatures and rainfall amounts in mountain areas vary considerably.
The Yungas, where the moist northeast trade winds are pushed up
by the mountains, is the cloudiest, most humid, and rainiest area,
receiving up to 152 centimeters annually. Sheltered valleys and
basins throughout the Cordillera Oriental have mild temperatures
and moderate rainfall amounts, averaging from 64 to 76 centimeters
annually. Temperatures drop with increasing elevation, however.
Snowfall is possible at elevations above 2,000 meters, and the permanent
snow line is at 4,600 meters. Areas over 5,500 meters have a polar
climate, with glaciated zones. The Cordillera Occidental is a high
desert with cold, windswept peaks.
The Altiplano, which also is swept by strong, cold winds, has an
arid, chilly climate, with sharp differences in daily temperature
and decreasing amounts of rainfall from north to south. Average
highs during the day range from 15° C to 20° C, but in the
summer tropical sun, temperatures may exceed 27° C. After nightfall,
however, the thin air retains little heat, and temperatures rapidly
drop to just above freezing. Lake Titicaca exerts a moderating influence,
but even on its shores, frosts occur in almost every month, and
snow is not uncommon.
Data as of December 1989
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