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Location: Northern Africa, bordering the Mediterranean Sea,
between Morocco and Tunisia
Geographic coordinates: 28 00 N, 3 00 E
Map references: Africa
Area:
total: 2,381,740 sq km
land: 2,381,740 sq km
water: 0 sq km
Area - comparative: slightly less than 3.5 times the size
of Texas
Land boundaries:
total: 6,343 km
border countries: Libya 982 km, Mali 1,376 km, Mauritania
463 km, Morocco 1,559 km, Niger 956 km, Tunisia 965 km, Western
Sahara 42 km
Coastline: 998 km
Maritime claims:
exclusive fishing zone: 32-52 nm
territorial sea: 12 nm
Climate: arid to semiarid; mild, wet winters with hot, dry
summers along coast; drier with cold winters and hot summers on
high plateau; sirocco is a hot, dust/sand-laden wind especially
common in summer
Terrain: mostly high plateau and desert; some mountains;
narrow, discontinuous coastal plain
Elevation extremes:
lowest point: Chott Melrhir -40 m
highest point: Tahat 3,003 m
Natural resources: petroleum, natural gas, iron ore, phosphates,
uranium, lead, zinc
Land use:
arable land: 3%
permanent crops: 0%
permanent pastures: 13%
forests and woodland: 2%
other: 82% (1993 est.)
Irrigated land: 5,550 sq km (1993 est.)
Natural hazards: mountainous areas subject to severe earthquakes;
mud slides
Environment - current issues: soil erosion from overgrazing
and other poor farming practices; desertification; dumping of raw
sewage, petroleum refining wastes, and other industrial effluents
is leading to the pollution of rivers and coastal waters; Mediterranean
Sea, in particular, becoming polluted from oil wastes, soil erosion,
and fertilizer runoff; inadequate supplies of potable water
Environment - international agreements:
party to: Biodiversity, Climate Change, Desertification,
Endangered Species, Environmental Modification, Hazardous Wastes,
Law of the Sea, Ozone Layer Protection, Ship Pollution, Wetlands
signed, but not ratified: Nuclear Test Ban
Geography - note: second-largest country in Africa (after
Sudan)
Algeria
GEOGRAPHY
Size: 2,381,741 square kilometers, more than fourfifths desert.
Topography: Sharp contrast between relatively fertile, mountainous,
topographically fragmented north and vast expanse of Sahara in south;
northern Algeria dominated by parallel ranges of Saharan Atlas mountain
system; no navigable rivers.
Climate: Mediterranean climate in coastal lowlands and mountain
valleys; mild winters and moderate rainfall. Average temperatures
and precipitation lower in intermountain Hauts Plateaux. Hot and
arid in desert; little seasonal change in most of country but considerable
diurnal variation in temperature.
Algeria
Geographic Regions
The Tell
The fertile Tell is the country's heartland, containing most of
its cities and population. Made up of hills and plains of the narrow
coastal region, the several Tell Atlas mountain ranges, and the
intermediate valleys and basins, the Tell extends eastward from
the Moroccan border to the mountains of the Grande Kabylie and the
Beja�a Plain on the east. Its eastern terminus is the Soummam River.
The best agricultural areas are the gentle hills extending 100
kilometers westward from Algiers; the Mitidja Plain, which was a
malarial swamp before being cleared by the French; and the Beja�a
Plain. The alluvial soils in these areas permitted the French to
establish magnificent vineyards and citrus groves. By contrast,
in the great valley of the Chelif River and other interior valleys
and basins, aridity and excessive summer heat have limited the development
of agriculture. The Grande Kabylie is a zone of impoverished small
farm villages tucked into convoluted mountains.
Data as of December 1993
Algeria
The High Plateaus and the Saharan Atlas
Stretching more than 600 kilometers eastward from the Moroccan
border, the High Plateaus (often referred to by their French name
Hauts Plateaux) consist of undulating, steppe-like plains lying
between the Tell and Saharan Atlas ranges. The plateaus average
between 1,100 and 1,300 meters in elevation in the west, dropping
to 400 meters in the east. So dry that they are sometimes thought
of as part of the Sahara, the plateaus are covered by alluvial debris
formed when the mountains eroded. An occasional ridge projects through
the alluvial cover to interrupt the monotony of the landscape.
Higher and more continuous than the Tell Atlas, the Sahara Atlas
range is formed of three massifs: the Ksour near the Moroccan border,
the Amour, and the Oulad Nail south of Algiers. The mountains, which
receive more rainfall than those of the High Plateaus, include some
good grazing land. Watercourses on the southern slopes of these
massifs disappear into the desert but supply the wells of numerous
oases along the northern edge of the desert, of which Biskra, Laghouat,
and B�char are the most prominent.
Data as of December 1993
Algeria
Northeastern Algeria
Eastern Algeria consists of a massif area extensively dissected
into mountains, plains, and basins. It differs from the western
portion of the country in that its prominent topographic features
do not parallel the coast. In its southern sector, the steep cliffs
and long ridges of the Aur�s Mountains create an almost impenetrable
refuge that has played an important part in the history of the Maghrib
since Roman times. Near the northern coast, the Petite Kabylie Mountains
are separated from the Grande Kabylie range at the eastward limits
of the Tell by the Soummam River. The coast is predominantly mountainous
in the far eastern part of the country, but limited plains provide
hinterlands for the port cities of Beja�a, Skikda, and Annaba. In
the interior of the region, extensive high plains mark the region
around S�tif and Constantine; these plains were developed during
the French colonial period as the principal centers of grain cultivation.
Near Constantine, salt marshes offer seasonal grazing grounds to
seminomadic sheep herders.
Data as of December 1993
Algeria
The Sahara
The Algerian portion of the Sahara extends south of the Saharan
Atlas for 1,500 kilometers to the Niger and Mali frontiers. The
desert is an otherworldly place, scarcely considered an integral
part of the country. Far from being covered wholly by sweeps of
sand, however, it is a region of great diversity. Immense areas
of sand dunes called areg (sing., erg) occupy
about one-quarter of the territory. The largest such region is the
Grand Erg Oriental (Great Eastern Erg), where enormous dunes two
to five meters high are spaced about forty meters apart. Much of
the remainder of the desert is covered by rocky platforms called
humud (sing., hamada), and almost the entire southeastern
quarter is taken up by the high, complex mass of the Ahaggar and
Tassili-n- Ajjer highlands, some parts of which reach more than
2,000 meters. Surrounding the Ahaggar are sandstone plateaus, cut
into deep gorges by ancient rivers, and to the west a desert of
pebbles stretches to the Mali frontier.
The desert consists of readily distinguishable northern and southern
sectors, the northern sector extending southward a little less than
half the distance to the Niger and Mali frontiers. The north, less
arid than the south, supports most of the few persons who live in
the region and contains most of the desert's oases. Sand dunes are
the most prominent features of this area's topography, but between
the desert areas of the Grand Erg Oriental and the Grand Erg Occidental
(Great Western Erg) and extending north to the Atlas Saharien are
plateaus, including a complex limestone structure called the Mzab
where the Mzabite Berbers have settled. The southern zone of the
Sahara is almost totally arid and is inhabited only by the Tuareg
nomads and, recently, by oil camp workers. Barren rock predominates,
but in some parts of Ahaggar and Tassili-n-Ajjer alluvial deposits
permit garden farming.
Data as of December 1993
Algeria
Climate and Hydrology
Northern Algeria is in the temperate zone and enjoys a mild, Mediterranean
climate. It lies within approximately the same latitudes as southern
California and has somewhat similar climatic conditions. Its broken
topography, however, provides sharp local contrasts in both prevailing
temperatures and incidence of rainfall. Year-to-year variations
in climatic conditions are also common.
In the Tell, temperatures in summer average between 21° C and
24° C and in winter drop to 10° C to 12° C. Winters
are not cold, but the humidity is high and houses are seldom adequately
heated. In eastern Algeria, the average temperatures are somewhat
lower, and on the steppes of the High Plateaus winter temperatures
hover only a few degrees above freezing. A prominent feature of
the climate in this region is the sirocco, a dusty, choking south
wind blowing off the desert, sometimes at gale force. This wind
also occasionally reaches into the coastal Tell.
In Algeria only a relatively small corner of the Sahara lies across
the Tropic of Cancer in the torrid zone, but even in winter, midday
desert temperatures can be very hot. After sunset, however, the
clear, dry air permits rapid loss of heat, and the nights are cool
to chilly. Enormous daily ranges in temperature are recorded.
Rainfall is fairly abundant along the coastal part of the Tell,
ranging from forty to sixty-seven centimeters annually, the amount
of precipitation increasing from west to east. Precipitation is
heaviest in the northern part of eastern Algeria, where it reaches
as much as 100 centimeters in some years. Farther inland the rainfall
is less plentiful. Prevailing winds that are easterly and northeasterly
in summer change to westerly and northerly in winter and carry with
them a general increase in precipitation from September to December,
a decrease in the late winter and spring months, and a near absence
of rainfall during the summer months.
Data as of December 1993
Algeria
Terrain
Clearing of land for agricultural use and cutting of timber over
the centuries have severely reduced the once bountiful forest wealth.
Forest fires have also taken their toll. In the higher and wetter
portions of the Tell Atlas, cork oak and Aleppo pine grow in thick
soils. At lower levels on thinner soils, drought-resistant shrubs
predominate. The grapevine is indigenous to the coastal lowlands,
and grasses and scrub cover the High Plateaus. On the Saharan Atlas,
little survives of the once extensive forests of Atlas cedar that
have been exploited for fuel and timber since antiquity.
The forest reserves in Algeria were severely reduced during the
colonial period. In 1967 it was calculated that the country's forested
area extended over no more than 2.4 million hectares of terrain,
of which 1.8 million hectares were overgrown with brushwood and
scrub. By contrast, woodlands in 1830 had covered 4 million hectares.
In the mid-1970s, however, the government embarked on a vast reforestation
program to help control erosion, which was estimated to affect 100,000
cubic meters of arable land annually. Among projects was one to
create a barrage vert (green barrier) more or less following
the ridge line of the Saharan Atlas and extending from Morocco to
the Tunisian frontier in a zone 1,500 kilometers long and up to
twenty kilometers wide.
The barrage vert consists principally of Aleppo pine,
a species that can thrive in areas of scanty rainfall. It is designed
to restore a damaged ecological balance and to halt the northern
encroachment of the Sahara. By the early 1980s, the desert had already
penetrated the hilly gap between the Saharan Atlas and the Aur�s
Mountains as far as the town of Bou Sa�da, a point well within the
High Plateaus region. The barrage vert project was ended
in the late 1980s because of lack of funds.
Data as of December 1993
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