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Life in the Saharaand the Sahel: Adaptingto a Desert Region

20.1 Introduction

The Saharan region is filled with the unexpected. Just ask someone who has

survived the Dakar Rally, a competition in which cars, trucks, and motorcycles

race not only against each other but also against the wind, sand, and heat ofthis desert. With few roads, the drivers speed over shifting dimes, rockyplains, and dry grasslands. They cross parched riverbeds that havetiot seen

water in years, and they struggle through sandstorms and scorching heat. Ifdriving across the Sahara is this difficult, think how much harder it must beto live there.

The Sahara is one of the harshest environments on Earth. Through the

years, however, people have adapted to living in this hot, arid region. Most

people live near a desert oasis, which is an isolated location where water isfound in a desert.

The Sahel is a semiarid grassland that is located along the Sahara'ssouthern edge. Although its environment is not quite as harsh as the Sahara,

the Sahel often suffers from drought, or long periods with very little or no

rain. This decrease in rainfall has made life in the Sahel even more challenging.

In this chapter, you will read about the physical features of the Sahara

and the Sahel. You will find out how the environments of these two regionshave been shaped by changes in climate. You will also learn how people

have adapted —and still are adapting —to the environments of these arid lands.

20

Essential Question

How do people adapt toliving in a desert region?

This map shows the vast

Saharan region, which includesthe Sahara and the Sahel.The

Sahara is the world's largest

desert.The Sahel is a wide belt

of semiarid lands to the south of

the desert. Over many centuries,

people have found ways to

survive in both of these dry

landscapes. Keep this map inmind as you try to answer

the Essential Question.

Graphic Organizer

The Sahara and'ttie Sahel,)/1 V&¥~v~ ,----;^"-"y -' ^('•••*jw. s-

,' " '' -- - .,' ,'. ' -', •:*

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A camel caravan carries trade goods across the Sahara.299

Shrinking Lake Chad

Lake Chad is a large, shallow lake inthe Sahel. The lake shrinks or growsdepending on the amount of rainfall.But its overall size is slowly shrinking

20.2The Geographic Setting

The Sahara stretches across most of North Africa, covering approxi-mately 3.5 million square miles, an area roughly equal to that of theUnited States. This huge desert region is bordered on the east by theRed Sea and on the west hy the Atlantic Ocean. To the north, the Saharahegins at the Atlas Mountains. From those mountains, the desert sweepssouth lor more than 1,0(10 miles, eventually merging with the semiaridSahel. Together, the Sahara and Sahel regions include all or parts of

15 African countries.

The World's Largest Desert The Sahara is the largest desert in theworld. Its name is derived from the Arabic word sahra, which means"desert." The region's climate is very hot and very dry. In fact, theworld's highest known daytime temperature, I36°F, was recorded in theSahara in 1922. Average rainfall is less than five inches a year.

The Sahara has not always been so dry. Many thousands of yearsago, the region had a much wetter climate. Rivers and lakes were filledwith fish, and elephants and other animals roamed through grasslandsand forests. People settled throughout the region and survived by hunting

and fishing.About 6,(KX) years ago, the climate of North Africa began to change,

as year by year less rain fell. Eventually the Saharan region began itstransformation into a desert. Ever since then, the desert has gradually

been expanding.Trade winds blowing across North Africa help to keep the region

dry. These winds begin in northern latitudes and blow south toward theequator. As trade winds pass over the Sahara, they pick up any moisturefrom the ground below, leaving so little moisture that few clouds formover the Sahara. With no clouds to provide shade, the sun beats down on

the land, making it even drier.Parts of the Sahara are so arid that nothing lives there, but in other

areas an oasis makes life possible. Most of the plants and animals thai

live in the Sahara are found near its oases.

The Sahel: On the Sahara's Edge The Sahel lies on the southernborder of the Sahara. Its name comes from the Arabic word sahel. whichmeans "border" or "shore." This region receives more precipitation thanthe Sahara, but it often suffers from long periods of drought.

Most of the Sahel is marginal land, land that is not well suited forfarming. People who farm marginal land may harvest barely enough food

for their families to survive.For thousands of years, pastoral nomads have adapted to lile on

the Sahel's marginal lands. Pastoral nomads are herders who wander end-lessly in search of water and grazing land for their animals. Once theirherds have grazed an area, the nomads move on. This gives marginal

grazing land a chance to recover.In more recent years, the Sahel region has been undergoing deserti-

fication, a process in which an area becomes increasingly dry. In thischapter, you will discover why parts of the Sahel are being transformedinto desert and what this desertification means for the people who live in

the region.

^ Geoterms

desertification the process by which land becomes more andrnore dry until it turns into desert. This may be caused byclimate change, human activities, or both.

drought an unusually long period in which little or no rain falls

marginal land land that is not well suited for growing crops

pastoral nomads groups of herders who move with theiranimals from place to place in search of pasture and water

North Africa

«o N ATLANTIC//OCEAN

A Vast Desert Region

The Sahara and Sahel stretch across most of North Africa. You can see howlarge this region is by looking at the inset map, which compares it to the size oftfie United States, fhe mountainous parts of this region receive the most rain-fall, fhe water seeps into underground streams that flow down to the desertbelow. In low areas, it may bubble up to the surface and create an oasis.

Life in the Sahara and the Sahel: Adapting to a Desert Region 301

The Sahara's Sea of Sand

Ergs, or vast expanses of sand, coverabout 13 percent of the Sahara's landarea. Sand dunes move like slow-breaking waves through these "seasof sand." Little grows on the dunes,and in some places the sand is sosoft that camels sink halfway to theirknees in it.

20.3 The Desert Environment

A line of 500 camels stretches for a mile across the desert. This camelcaravan is (raveling to retrieve blocks of sail from a distant mine, endur-ing a difficult 400-mile round trip that will take 30 days. Along the way,the caravan will pass camel hones and abandoned trucks, grim evidence(hat travel is not easy in the Sahara.

The Desert Landscape: More Than Just Sand Many people picturethe Sahara as a sea of burning sand, but its landscape is actually farmore diverse. In just a single afternoon, a traveler in the Sahara saw''pink and yellow dunes, blue craggy cliffs, black volcanic rubble... aneroded gulch, two dry rivers, a cone, a canyon, [and| many badlands[barren hills)."

The Sahara lias three principal types of landlui MIS: ergs, regs, andhammadas. Ergs are great seas of sand with tall sand dunes that canreach heights of over 400 feel. Most dunes are slowly blown across thedesert by the wind. Regs are gravel-covered plains. Hammadas arc high,rock-covered fiatlands, some of which arc so tall that maps indicate, theirlocations as mountains.

Only two rivers flow through the Sahara: the Nile and the Niger,with the wafer in both rivers coming from mountains beyond the desert.There are also dry riverbeds called wadis that can turn into raging riversafter a rain and then quickly dry up again.

The Harsh Desert Climate Temperatures can vary greatly in the desert,often soaring above IOO°F during the day and sometimes dropping belowfreezing at night. According to an old saying, "Nighttime is the winter ofthe desert."

Sandstorms can begin when strong winds stir up enormous dark cloudsof dust and sand from the desert floor. A severe desert sandstorm can reducevisibility to practically nothing while also getting sand into everything.

Rain is extremely unpredictable throughout.the desert. During adesert rainstorm, it may rain three inches in one spot, while nearby norain falls. When rain does come to a parched area, the water may quicklyfill the wadis, resulting in Hash Hoods that can carry away rocks, people,and even trucks.

Plants are able to adapt to these changing conditions in several ways.Some plants sprout rapidly after a rain and then set seed and die. Theseeds then lie in wait, sometimes for years, until the next rain. Otherplants send roots deep into the ground to find water. Deep roots anchorthese plants in place during sandstorms and flash floods. Most deserttrees and shrubs have small, waxy leaves that lose little moisture. Duringlong periods of drought, they may shed their leaves, further reducingwater loss.

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20.4 Adaptations to LifeIn the Desert

About a thud of the people who live inthe desert arc pastoral nomads. Manydesert nomads belong to a group knownas the Tuareg. The Tuareg live in sixcountries in the southern Sahara andtheSahel.

The Wandering Tuareg The nomadicTuareg raise camels, goats, cattle, orsheep. When the pasture in one area hasbeen exhausted, or used up, the Tuaregmove their animals to a fresh grazing area.

The Tuareg are known as the "UlueMen of the Desert" because of their(lowing blue robes. Their long, looseclothing protects them from the scotching sun. Men also wear blue clothwrapped around their heads and across their faces. Some Tuareg mennever remove Ihis face cover, even in the presence of close family members.

Tuareg nomads live in family groups of fewer than UK) people.Always prepared to move, a Tuareg family needs only two hours to dis-assemble the tents that are their homes and pack up their belongings.All of a family's possessions will tit on one camel or two donkeys. Whenthe nomads reach an oasis, they trade meat, cheese, or milk for grain,vegetables, fruit, and water.

Tuareg traders lead camel caravans across the desert. Camels canwalk long distances over sandy ground with litlle food or water, makingthem well suited for desert travel, ft is easy for travelers to get lost in theSahara, but the Tuareg know the local landmarks. They also know howto use the stars to find their way, enabling them to travel at night whenthe air is cooler.

Technology Mokes Life Easier Modern technology has improved lifefor many desert dwellers. Pastoral nomadshave found many uses for lightweightplastic and metal containers. Meanwhile.some desert traders can afford satellitephones lo keep in touch wild theircustomers.

Technology has even created newoases. Drilling machines cut through rocklo locate underground water, and electricpumps then draw this water to the surface.

Trucks and planes have improveddesert transportation. Trucks are replacingcamels for hauling heavy loads, and smallplanes are used to fly people and goodsbetween oases.

Nomads Tend Their Herds

Tuareg nomads move their herds tofind water.or better pasture. TheTuareg depend upon their animals formilk. They trade milk, cheese, andsome meat for the goods they cannotmake or grow themselves.

Trucks Replace Camels

Trucks are gradually replacing camelsin the Sahara. There are not manyroads, though, so trucks are built todeal with the rough and sandy desert.The owner of this truck has to clearaway the sand that has piled up over-night before beginning the day's work.

Life in the Sahara and the Sahel: Adapting to a Desert Region 303

Desert Oases

An oasis is a place in the desert wherewater is found. Some oases are natural.Others have been created by people.However they came to be, all oases areprecious. They allow life to exist in oneof the world's harshest environments.

Rock layers

20.5The Oasis Environment

The Sahara region holds many surprises, including a variety of life. In ahidden canyon oasis, crocodiles feed on fish and on animals that come todr ink. At a larger oasis, thousands of date palms provide shade for otherf r u i t Irees, and wild gazelles graze nearby. In the arid Sahara, where thereis water there is life.

Islands of Water Surrounded by Desert For weary, thirsty travelerstrekking across the Sahara, no sight is more welcome than the appearanceof a distant palm tree, a sign that they are approaching an oasis. Eachoasis is an island til fresh water in a sea of"dry sand and rock.

Some oases are formed by natural processes. Many are created bysprings that bubble up to the surface from streams that flow beneath theground. Other oases appear in low spots, where the land dips down tomeet an underground stream.

Humans have also created some oases. In the past, people constructedoases by digging wells by hand. As you read earlier, dri l l ing machinesare now being used to dig deep into the ground to locate hidden water.

l a rye and Small Centers of Life The Sahara has approximately 90large oases. Each large oasis can supply enough water to support a villageand small farms. In addition, there are many small oases, with some sup-porting only one or two families.

Many species of plants and animals can be found at a desert oasis.Acacia and baobab trees mix with smaller shrubs. Gazelles and otheranimals drink in the pools, while butterflies, crickets, and other insectsfl i t through oasis gardens.

Date palms are by far the most important and common oasis plant.Every part of the date palm is useful. Its frui t , the dale, is eaten fresh ordried. Its t runk and leaves are used as bui lding materials, and the fiberfrom its bark is twisted together to make rope. Date pits, or seeds, areburned as fuel or fed to animals. A visitor to the Sahara once wrote,

These magnificent palm groves are the blood and bone oj the desert;

life in the Sahara would be unthinkable without them.... The size ofan oasis is reckoned by the number of trees it contains, not by the

number oj'square miles if covers.

20.6 Adaptations to Lifein the Oases

Most oasis settlements are relat ively small,accommodating fewer than 2,000 people. Thelargest oases may support thousands of datepalms, but in an oasis that has little water, severalfamilies may have to share a single dale palm.

TheTraditional Ways of Oasis SettlersTrading and farming are the major economicactivities at an oasis. Most people arc subsistencefarmers, but others grow cash crops such asdates, wheat, barley, and vegetables. Farmersexchange their produce for goods brought in byciimel, t ruck, and plane, while visi t ing nomadstrade their meat, mi lk , and cheese for water andfood. Caravans and trucks stop to trade and to f i l ltheir containers with water.

Most homes wi th in an oasis town are con-structed from mud bricks; in order to keep outthe heal, the homes have few windows. Littlework is done dur ing the hottest part of the day.hi the cool of the evening, men gather to discussthe day's news.

An oasis farmer is always struggling againstIhe harsh desert environment. Blowing sand andcreeping dunes w i l l rapidly cover crops unless theplants are protected by wiudhraiks, which are walls or hedges that breakthe force of the wind. Windbreaks can also prevent sand from pi l ing upon farm fields.

Water Problems Limit the Growth of Oasis Towns Oasis settlementscome in a variety of sizes. Most arc small villages, but a few settlementsarc growing into towns anil cities. As an oasis settlement expands, itswater problems increase as well .

People move to an oasis for many reasons. Some may be looking forjobs on date farms or in dale-processing factories thai prepare dales forexport. Nomads sometimes settle at an oasis when they can no longerMud pasture for their animals . Refugees from drought or wars may moveto an oasis in search of water, food, and safely.

Growing oasis set t lements face two kinds of water problems. Thefirst challenge is how to transport water to people as the town expands.New housing areas ami camps that arc established to shelter refugeesoften lack wells or piped water. If the residents of these set t lementscannot walk to water sources, wnicr may have to he brought to themby truck.

Water shortages are the second problem facing oasis towiis. In someoases, palm groves have been expanded into the surrounding desert.The new palm trees are kept alive w i th water that is pumped out of Iheground. However, if too much water is pumped out, the undergroundstreams that create an oasis could run dry.

Palms Produce a Cash Crop

Date palms produce the desert's mostvaluable cash crop. Other fruit treesare often planted in the shade of datepalms.

Life in the Sahara and the Sahel: Adapting to a Desert Region 305

Cattle in the Sahel

Overgrazing by cattle is a major causeof desertification in the Sahel. Whentoo many cattle graze in an area, theydestroy its cover of plants. Withoutthis protective cover, the soil is erodedby wind or water.

20.7 The Sahel Environment

A television advertisement in southern Niger begins by panning slowlyacross a desert landscape. The next scene focuses on camels, donkeys,and trucks carrying firewood into towns. A quick cul shows a coal-miningoperation. The advertisement ends by showing a woman cooking withcoal in her smoke-tree kitchen. The purpose of the advertisement is topersuade people in Niger to switch from using wood to coal for cooking,in the process helping to preserve Niger's Irees and perhaps, in the longrun, to prevent desertification.

The sou them' area of Niger is part of the Sahel. Other areas of theSahel include Gambia and parts of Senegal, Mauritania, Mali, BurkinaFaso. Nigeria. Chad, and Sudan. In good years, just enough rain falls inthe Sahel to grow crops. During years of drought, life in the Sahel regionbecomes very difficult.

A Landscape Threatened by Drought and Desertification TheSahel region begins at the Sahara's edge. The land here is marginal forfanning because the soil is not fertile atid water is scarce most of theyear. The natural vegetation of the Salicl is a mixture of grasslands,acacia trees, baobab trees, and small bushes. Farther south, where rainis more plentiful, there is a greater variety of vegetation.

Drought is a fact of life throughout the Sahel. One severe droughtbegan in 1968, and very little rain fell during the next six years. Sincethen, there has been some rain, but not enough for the land to recovercompletely.

As the drought continued, desertification began, In areas with littlerain, few plants grew. Without vegetation to anchor the dry soil in place,desert winds picked up the soil and carried it away. When this happened,marginal lands were transformed into desert. Experts aren't sure whetherdesertification in the Sahel is a short-term problem or whether these mar-ginal lands will be lost forever to an expanding Sahara.

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20.8 Adaptations to Life in the Sahel

Most people in the Sahel arc farmers or herders. In the past, these peoplehave adapted to the challenge of fanning and herding on marginal land inmany ways.

One adaptation was to plant crops such as millet and sorghum,which are grains that will flourish in dry places. Another adaptation wasto use a farming system known as shifting agriculture. In this method,a farmer first cleared a field and planted it with crops for a year or two.Then the farmer moved on to a new field. Herders used a similar systemto feed their animals, moving their herds from one grazing area to anotherthroughout the year. Both of these systems provided worn-out fields withart opportunity to rest.

Human Causes of Desertification The changing ways of life in theSahel may be contributing to desertification. Some farmers, for example,have begun to raise cash crops, like peanuts, which often wear out thesoil faster than traditional crops. After the soil has been depleted, or wornout, it may blow away before it can recover its fertility.

Similarly, some nomads have increased the size of their herds so that(hey have surplus animals to sell for cash. The result is too many animalson limited grazing land. Loss of vegetation from overgrazing may alsocontribute to desertification.

Yet another problem is deforestation. Most people in the Sahel relyon wood as their fuel for cooking. In their search for firewood, the peoplecut down trees. When the trees are gone, soil erosion increases, which iswhy the government of Niger has been promoting coal as a cooking fuel."1 think that with coal, our sparse forests could be saved," says a forestryexpert in Niger.

Cooking with coal is only one of the changes that people are makingto counteract desertification. In addition, farmers are testing new agri-cultural methods that can conserve water and reduce soil erosion. Manyfarmers are working to keep desert sand from burying their fields bybuilding windbreaks of trees and brush.

No one can say how successful this war against the desert will be.However, for the people of the Sahel. this struggle against desertificationis a fight they cannot afford to lose.

20.9 Beginning to Think Globally

In this chapter, you learned how people have adapted to living in theSahara and the Sahel. Pastoral nomads survive by staying on the move.Fanners adapt by settling around oases that serve as fanning and tradingcenters in this arid land. You found out how people have learned to raisecrops and animals on the marginal lands of the Sahel. In addition, youexplored the effects of drought and desertification on the Sahel region.

The Sahel is not the only area in the world that continues to beIhreatened by desertification. About one third of Earth's land is arid orsemiarid, and some of these desert regions are expanding. In China, forexample, the capital city of Beijing is sometimes blasted by sandstorms.This blowing sand comes from parts of China that are undergoing deser-tification. Think about the causes of desertification as you examine theworld map of arid regions in the next section.

Sahel Sandstorm

Sandstorms like this one in Mali aremade worse by desertification. Windspick up loose soil from worn-out landand blow it away. Dust from the Sahelis sometimes carried across theAtlantic Ocean. When this dust reachesFlorida, it creates reddish sunsets.

Life in the Sahara and the Sahel: Adapting to a Desert Region 307