SECTION 3 Land Management and Conservation · Describe two ways that rangeland can be managed sustainably. Describe the environmental effects of deforestation. Explain the function

Section 3 Land Management and Conservation 363

As the human population grows, the resources of more rural landare needed to support the population. The main categories ofrural land are farmland, rangeland, forest land, national and stateparks, and wilderness. Throughout our history, we have some-times managed these lands sustainably so that they will provideresources indefinitely. We have also sometimes reduced their pro-ductivity by overusing or polluting them. The condition of ruralland is important because of the ecological services that it pro-vides. These services are especially important for the urban areasthat rely on the productivity of rural land.

FarmlandsFarmland, such as that shown in Figure 12, is land that is used togrow crops and fruit. The United States contains more than 100million hectares of prime farmland. However, in some places,urban development threatens some of the most productive farm-land. Examples of places where farmland is threatened are partsof North Carolina’s Piedmont region and the Twin Cities area ofMinnesota. In 1996, the U.S. government established a nationalFarmland Protection Program to help state, county, and localgovernments protect farmland in danger of being paved over orotherwise developed.

Objectives� Explain the benefits of preserving

farmland.� Describe two ways that rangeland

can be managed sustainably.� Describe the environmental effects

of deforestation.� Explain the function of parks and

of wilderness areas.

Key Termsovergrazingdeforestationreforestationwilderness

S E C T I O N 3

Land Management and Conservation

EcofactHedgerows Farmland forms animportant habitat for wildlife inGreat Britain, which has relativelyfew remaining natural areas. Fieldsare separated by rows of bushescalled hedgerows, which provideshelter for a variety of birds, mam-mals, reptiles, and insects.

Figure 12 � This farmland next tothe suburbs of Mililani, Hawaii, isused to grow a variety of crops.

Copyright© by Holt, Rinehart and Winston. All rights reserved.

RangelandsLand that supports different vegetation types like grasslands,shrublands, and deserts and that is not used for farming or tim-ber production is called rangeland. Rangelands can be arid, likerangelands in the desert Southwest, or relatively wet, like therangelands of Florida. The most common human use of range-land is for the grazing of livestock, as shown in Figure 13. Themost common livestock are cattle, sheep, and goats, which arevalued for their meat, milk, wool, and hides. Native wildlifespecies also graze these lands. Like farmland, rangeland is essen-tial for maintaining the world’s food supply. World populationgrowth may require a 40 percent increase in the food productionof rangeland from 1977 to 2030.

Problems on the Range Some rangelands in the United Stateshave become degraded by poor land management strategies.Most damage to rangeland comes from or allowingmore animals to graze in an area than the range can support.When animals overgraze, too many of the plants are eaten, andthe land can become degraded. Overgrazing often results inchanges in the plant community. Less desirable plant species mayinvade the area and replace more-desirable plant species. In casesof severe overgrazing, all the vegetation that covers the land iseaten. Once the plants are gone, there is nothing to keep the soilfrom eroding.

Maintaining the Range Much of the rangeland in the UnitedStates is public land managed by the federal government, whichleases the rangeland to ranchers. Much of the rangeland in theUnited States is degraded. The Public Rangelands ImprovementAct of 1978 was enacted to reverse this trend and improve landmanagement practices.

Sustaining the productivity of rangeland generally meansreducing overgrazing by limiting herds to sizes that do not

degrade the land. Rangeland isalso left unused for periods oftime so that the vegetation canrecover. Improving rangelandthat has been degraded by over-grazing often includes methodssuch as killing invasive plants,planting native vegetation, andfencing areas to let themrecover to the state they were inbefore they were overgrazed.Ranchers also control grazingby digging enough small waterholes that livestock do not over-graze the vegetation around asingle water hole.

overgrazing,

364 Chapter 14 Land

www.scilinks.orgTopic: RangeManagementSciLinks code: HE4091

Figure 13 � The photo below showsproductive rangeland in the westernUnited States.


Forest LandsTrees are harvested to provide products we use everyday, such aspaper, furniture, and lumber and plywood for our homes. Inaddition to wood and paper, we also value forest products suchas maple syrup and turpentine. There are many ecosystem serv-ices provided by forests; however, one of the most important isthe removal of CO2 from the air.

Harvesting Trees People use enormous amounts of wood. Theworldwide average is 1,800 cm3 of wood used per person eachday. However, on average, each person in the United States usesabout 3.5 times this amount. This is the equivalent of each per-son in the United States cutting down a tree that is 30 m tallevery year. About 1.5 billion people in developing countriesdepend on firewood as their main source of fuel.

The timber industry classifies forest lands into threecategories—virgin forest, which is forest that has never been cut;native forest, which is forest that is planted and managed; andtree farms, which are areas where trees are planted in rows andharvested like other crops. The two most widely used methods ofharvesting trees are clear-cutting and selective cutting. Thesemethods are shown in Figure 14. Clear-cutting is the process ofremoving all of the trees from an area of land. Clear-cutting largeareas destroys wildlife habitat and causes soil erosion. The mainalternative is selective cutting, which is usually practiced onsmaller areas owned by individuals. Selective cutting is theprocess of cutting and removing only middle-aged or maturetrees. Selective cutting is more expensive than clear-cutting, butselective cutting is usually much less destructive.


QuickLABMeasuring Soil Depth and CompactionProcedure1. Find a plot of undisturbed soil

in a forest, meadow, park, orother undisturbed area nearyour school.

2. Press a meterstick down intothe undisturbed soil as far as itwill go. Record how deep themeterstick went into the soil.Record how soft the soil wasand how easy it was to pressthe meterstick into the soil.Repeat this five times in thesame plot of undisturbed soil.

3. Pour 1 L of water onto theundisturbed soil. Use a stop-watch to record how long ittakes for the soil to fully absorbthe water.

4. Repeat this procedure at a plotof disturbed soil in a bike path,dirt road, or other area wherethe soil is bare and vegetationhas been cleared or trampled.

Analysis1. How did the soil depth and

hardness in the plot of undis-turbed soil differ from that inthe plot of disturbed soil?

2. Which plot absorbed waterfaster?

3. How might grazing cattle affectthe depth and compaction ofan undisturbed plot of land?

4. How might clear-cutting affectan undisturbed plot of land?

Figure 14 � Methods for harvestingtrees include clear-cutting (top) andselective cutting (bottom).


Deforestation The clearing of trees from an area without replac-ing them is called Most countries become severelydeforested as populations expand and the demand for forestproducts increases. Forests are cleared to convert the land intofarmland. People also clear forests to make space for roads,homes, factories, and office buildings.

Deforestation reduces wildlife habitat, but it has otherimpacts, too. For example, when forests are cleared from hill-sides, soil erosion usually results if the area is not quickly plantedwith a cover crop. Without tree roots to hold the soil in place,soil is easily washed or blown into the valley below. In NewYork, forests on hillsides were cleared for farmland during the19th century. Plowing also increased the rate of erosion, and asmuch as 90 percent of the soil eroded. Then, during the GreatDepression, which was in the 1930s, hundreds of farmers in thisarea went bankrupt. The state bought many of these abandonedfarms, and let the forests regenerate. Today, many of these hill-tops are covered with state forest, which is used for recreation.

The rate of deforestation is especially high in tropical rainforests, where the soil is relatively thin. Farmers who clear forestsin these areas must always move from one plot of land to anotherand clear more forest each time they move. Whether forests arecleared for farming or wood, if trees are not replanted, naturalresources are steadily depleted.

deforestation.

366 Chapter 14 Land

California’s Wilderness Corridors

California has an extraordinary rangeof habitats, from coastal islands,where elephant seals breed, tomountains where salmon, cougars,bobcats, and badgers are found.Many of these animals live onwildlife preserves and other publiclands or on private land.

Animals do not know that theyare safest if they stay on preserves.Many animals naturally migrate atdifferent times of the year. Younganimals are often evicted from theirterritories by their parents and mustsearch for territories of their own tosurvive. Many animals also leave theirterritories in search of mates fromother populations. This process is

important because if animals repro-duce only with members of thespecies that live nearby, the popula-tion becomes inbred and geneticdefects become more common.

As California becomes moreurbanized, however, migrationroutes between one population ofanimals and another population areincreasingly blocked by highwaysand housing developments.

A possible solution is theacquisition of conservation corri-dors—thin strips of protected landthat connect one preserve withanother preserve. Conservationbiologists have argued for yearsover whether such corridors are

� This diagram shows suspectedwildlife corridors around LosAngeles, California.

EcofactBurning Trees and CO2 Whentrees are cut and burned, theyrelease carbon dioxide. From 1850to 1990, deforestation releasedmore than 100 billion metric tonsof carbon dioxide into the atmos-phere worldwide. Some scientiststhink this additional CO2 is con-tributing to an increase in globaltemperatures.


Reforestation Clear-cut forest can be replanted or allowed toregrow naturally, without human intervention. isthe process by which trees are planted to re-establish trees thathave been cut down in a forest land. In some places, reforesta-tion is happening faster than trees are being cut down. NewEngland, for example, now contains more forest than it did acentury ago. Much of the original forest had been cleared forfarming, but the land was unable to sustain productive cropsover a long period. As farming in this area became less eco-nomical, farms were abandoned and the forest regenerated. Thesame process has happened in places where steep hillsides weredeforested for farming or development. The cost of deforesta-tion, which caused soil erosion, landslides, and flooding, wastoo high. So forest has now been allowed to regenerate or hasbeen replanted.

Some governments require reforestation after timber has beenharvested from public land. A reforestation project is shown inFigure 15. Worldwide, more than 90 percent of all timber comesfrom forests that are not managed by an agency that monitors thehealth of forest ecosystems. Many governments are currentlyworking to improve reforestation efforts and to promote lessdestructive logging methods. Private organizations have alsoestablished tree-planting programs on roadsides and in cities.

Reforestation


effective in linking habitats andprotecting animals.

One such corridor in Californiais the Tenaja corridor, which con-nects the Santa Rosa PlateauEcological Preserve and the largerCleveland National Forest in theSanta Ana Mountains southeast of

Now there is public pressure topreserve 232 of the corridors thatlink critical habitats. Voters haveapproved bond measures that willsupply the money to buy some ofthe land, and the Nature Conser-vancy is also contributing land. Thequestion of whether wildlife corri-dors preserve species may finally beanswered by California’s initiative.

Los Angeles. Biologist Paul Beir stud-ied the movements of a populationof cougars in the Santa AnaMountains by putting radio collarson more than 30 animals to tracktheir movements. He found that theanimals used the Tenaja corridorand avoided urban areas.

� Cougars may need wildlife corridors in order to survive in parts of California.

Figure 15 � Tree seedlings havebeen planted to reforest this hillsideas part of a reforestation project inthe Fiji Islands.

CRITICAL THINKING

1. Applying Ideas California’sstate emblem is a grizzly bear,which is a species no longer foundin the state. Why do you think thebears disappeared?

2. Expressing ViewpointsShould California spend statemoney to preserve habitats? Explainyour answer.


Parks and PreservesIn the 1870s, a group of explorers approached Congress withnews of a magnificent expanse of land in Wyoming andMontana. These explorers expressed their concern that this landwould be damaged by the development that had changed thenortheastern United States. Congress agreed to protect this landby setting it aside for the public to use and enjoy, and the firstnational park—Yellowstone—was created. Today, the UnitedStates has about 50 national parks, as shown in Figure 16. If youare a U.S. citizen, you share ownership of these lands.

Public lands in the United States have many purposes. Mostpublic lands are not as protected as the national parks are. Somepublic lands are leased to private companies for logging, mining,and ranching. Other public lands are maintained for hunting andfishing, as wildlife refuges, or to protect endangered species.

International efforts include the United Nations’s Man and theBiosphere Program. This program has set up several hundred pre-serves throughout the world since 1976. These preserves are calledbiosphere reserves and are unusual in that they include people inthe management plan of the reserves, as shown in Figure 17.

Wilderness The U.S. Wilderness Act, which was passed in 1964,designated certain lands as wilderness areas. is an areain which the land and the ecosystems it supports are protectedfrom all exploitation. Wilderness areas are found within several ofthe nation’s public land systems. So far, 474 regions coveringalmost 13 million hectares (32 million acres) have been designatedas wilderness in the United States. Figure 18 shows an example ofa wilderness area. These areas are open to hiking, fishing, boating(without motors), and camping. Building roads or structures andusing motorized equipment is not allowed in wilderness areas.

Wilderness

368 Chapter 14 Land

Corearea

River

Buffer zone 1

Buffer zone 2

Human settlement

Tourism and education center

Research station

Figure 17 � Biosphere reserves areplaces where human populations andwildlife live side by side.

Figure 16 � National parks in theUnited States are concentrated inthe West.


Benefits of Protected Areas Withoutnational and private parks and preservesaround the world, many more species wouldnow be extinct. In a crowded world, theseprotected areas often provide the only placewhere unspoiled forests, deserts, or prairiesremain. Without these areas, the plants andanimals that can survive only in these ecosys-tems would disappear. These protected areasalso provide recreation for people. People cancamp, hike, fish, and watch birds and otherwildlife in these areas. Wilderness areas alsoserve as outdoor classrooms and research laboratories where people can learn moreabout the natural world.

Threats to Protected Areas There is a con-stant battle in our world between our conser-vation efforts and the growing andincreasingly mobile population. Around theworld, more people visit national parks andwilderness areas each year and leave theirmark on the land. Litter and traffic jams thathave plagued our cities now plague many ofour national parks. Rangelands, mining andlogging sites, oil and gas drilling operations,factories, power plants, and urban areas areoften close enough to the parks to affect theparks. In addition, preserved areas are affectedby climate change and by air and water pollu-tion, as are most other parts of the world.

In attempts to protect wilderness fromdamage, limits have been set in some areas on the number of peo-ple permitted in the area at any given time. Some areas are com-pletely closed to visitors to allow wild animals to breed. Inaddition, volunteer programs are now active in many wildernessareas. Volunteers help pick up trash, build trails, control invadingor exotic species, and help educate the visiting public.


1. Explain what reforestation is and why it is important.

2. List and explain two methods of managing range-lands sustainably.

3. Describe the function of parks and of wilderness.

4. Describe the environmental effects of deforestation.

CRITICAL THINKING5. Recognizing Relationships Read the first para-

graph under the head “Threats to Protected Areas.”Why do you suppose that some of our nation’snational parks and wilderness areas are degraded?

6. Recognizing Relationships What are the benefitsof preserving farmland?

READING SKILLS

S E C T I O N 3 Review

Figure 18 � In the United States,wilderness areas, such as the HighUintas Wilderness area shown here,are supposed to be preserveduntouched for our own and futuregenerations.


HighlightsC H A P T E R 14

1 How We Use Land

2 Urban Land Use

3 Land Managementand Conservation

370 Chapter 14 Highlights

Key Termsurban, 355rural, 355ecosystem services,

357

Main Ideas� Land is covered with forest, farm fields andpastures, roads, and towns.

� Urban areas are mostly covered withhouses, roads, businesses, and industrial andmunicipal structures. Rural areas have lessdense human populations and include forestland, cropland, rangeland, and other landcover types.

� Urban areas need very large areas of ruralecosystems to supply them with water, food,wood, and other ecosystem services.

urbanization, 358infrastructure, 359urban sprawl, 359heat island, 360land-use planning,

361geographic informa-

tion system (GIS),361

� Urbanization is the migration of people fromrural to urban areas.

� When cities grow more rapidly than infra-structure can be built, they tend to sufferfrom substandard housing and traffic problems.

� Unplanned growth of a city results in urbansprawl, as low-density development spreadsinto the surrounding countryside.

� Land-use planning is essential if urban areasare to be pleasant places to live.

overgrazing, 364deforestation, 366reforestation, 367wilderness, 368

� Farmland is used to raise crops and livestock.

� Rangeland is land used primarily for graz-ing livestock. Rangeland is easily degraded byovergrazing.

� Trees are harvested for many purposes.Deforestation can cause soil erosion and maythreaten forest plants and animals withextinction.

� National lands are used for many purposes,including lumber, mining, and recreation.Wilderness is national land that is protectedfrom all exploitation for the benefit of futuregenerations.


Review

Chapter 14 Review 371

Using Key TermsUse each of the following terms in a separatesentence.

1. rangeland2. infrastructure3. urbanization4. ecosystem services5. geographic information system

For each pair of terms, explain how the meaningsof the terms differ.

6. heat island and urban sprawl7. overgrazing and deforestation8. urban and rural9. selective cutting and clear-cutting

Understanding Key Ideas10. Building a mass transit system is likely to

have which of the following effects?a. increasing air pollutionb. traffic congestionc. increasing the temperature of the urban

heat islandd. none of the above

11. National parks and wilderness areas aredesigned to do which of the following?a. provide recreationb. protect wildlifec. preserve natural areasd. all of the above

12. Which of the following is not an example ofurbanization?a. Immigrants settle in New York City.b. A farmer who can no longer afford to lease

farmland moves to a city.c. A drop in timber prices in Oregon causes a

lumberjack to lose his job and he moves toPortland.

d. An Indian family moves to the city ofCalcutta after a landslide destroys theirvillage.

13. Which of the following is not an example ofinfrastructure?a. a railroadb. a schoolc. a telephone lined. a dairy farm

14. Which of the following is a likely result ofdeforestation?a. The amount of carbon dioxide removed

from the atmosphere is reduced.b. Wind blows soil away because its plant

cover has been removed.c. Water runs off the land more rapidly and

causes floods.d. all of the above

15. Which of the following is not likely to causethe degradation of rangeland?a. adding more animals to a herd grazing on

rangelandb. a drought in which rainfall is lower than

usual for three yearsc. planting grass seed on the landd. driving a vehicle off-road

16. Which of the following is an example ofreforestation?a. replanting forest land that has been

clear-cutb. planting a cherry tree in your backyardc. planting oak trees in a cityd. all of the above

17. Which of the following is not an ecosystemservice provided by rural lands?a. oxygen in the airb. foodc. aesthetic beautyd. wood for making paper

C H A P T E R 14

Flash Cards With a partner, make flash cards forthe key words and most important ideas in thechapter. Take turns quizzing each other about thecontent of the course. Do another round, and thistime the person being asked questions should try touse each key word and idea in a complete sentence.

STUDY TIP


ReviewShort Answer18. Explain one way rangeland can be degraded.19. Do national parks and forests in the United

States protect ecosystems from human activi-ties? Explain your answer.

20. What is the difference between a U.S.wilderness area and a national park?

21. Are national parks located only in theUnited States?

22. How can building a mass transit systemimprove living standards in an urban area?

Interpreting GraphicsThe map below shows a typical UN BiosphereReserve. Use the map to answer questions 23–25.23. Where is the reserve’s research station

located, and why has it been placed thererather than anywhere else in the reserve?

24. What indicators can you see that this reservemight be an ecotourism destination?

25. What does the map tell you about the func-tion of buffer zone 2?

Concept Mapping26. Use the following terms to create a concept

map: geographic information system, land-use planning, infrastructure, population, andurban area.

Critical Thinking27. Recognizing Relationships Read about

clear-cutting under the head “HarvestingTrees.” What effects does clear-cutting a hill-side have on the environment?

28. Drawing Inferences If we see many invasiveplant species and large areas of bare soil onrangeland, what conclusions can we drawabout the land management practices on thisrangeland? Explain your answer.

29. Evaluating Assumptions We tend to thinkthat the main use of livestock is for meat.However, the Masai herders of Africa do notslaughter their cattle. They use the milk. Theyalso bleed the cattle and use to the blood tomake a protein-rich sausage. What other usesfor livestock can you think of that do notinvolve killing the animals?

Cross-Disciplinary Connection30. History Find out how deforestation has

affected a community. If you live in a forestbiome, you can document the effects of defor-estation on local rivers and farmland. If not,you will probably have to find an example onthe Internet or in a magazine. Write a para-graph for your answer, using at least threekey terms from this chapter.

Portfolio Project31. Research Diagram the growth of your com-

munity over the last 100 years. Express thisas a graph that shows the growth of the population and a map that shows the area ofground the community covers. There arevarious possible sources for the data you willneed. If there is a local historical society, thisis probably the best source. Otherwise, cityhall or the local newspaper will probablyhave the information.

WRITING SKILLS

READING SKILLS

C H A P T E R 14

372 Chapter 14 Review

Corearea

River

Buffer zone 1

Buffer zone 2

Human settlement

Tourism and education center

Research station

?

? ?


Chapter 14 Review 373

Read the passage below, and then answerthe questions that follow.

When more people live in a city than its infra-structure can support, living conditions deteri-orate. For example, many people do not haveaccess to clean water for drinking and wash-ing. In addition, overcrowding causes theprices of existing houses and apartments to riseabove the reach of many workers. Increasingnumbers of people become homeless. Theseproblems have become so widespread through-out the developed and developing world, that the term urban crisis was coined todescribe the problem. According to the UnitedNations, the crisis is so bad that almost one-fourth of the world’s city dwellers could behomeless by the year 2020.

1. According to the passage, which of thefollowing statements is true?a. Cities have grown so rapidly that the

rural areas that supply the cities withfood and fuel cannot do so fastenough.

b. Overcrowded cities lead to unafford-able housing and homelessness.

c. The urban crisis does not usuallyinvolve water pollution.

d. Living conditions usually improvewhen the population of a city increases.

2. Which of the following is an example ofthe urban crisis, according to the passage?a. To make space for more cars, roads

into and through a city are widened.b. Deforestation in the countryside sur-

rounding a city causes the water levelin a river that flows through the city toincrease when it rains.

c. Homelessness is increasing rapidly incities in both developed and developingcountries.

d. Inadequate planning for a growingnumber of commuters results in trafficjams on roads leading into the city inrush hour.

MATH SKILLS

The graph below shows land cover in the UnitedStates in 1997. Use the graph below to answerquestions 32–33.

32. Analyzing Data If the percentage of crop-land increased to 25 percent, and all otherland cover categories except for rangelandand pasture remained the same, what per-centage would rangeland and pasture be?

33. Making Calculations What percentage of the United States is planted in crops if 11percent of cropland is idle (unplanted) at anyone time?

WRITING SKILLS

34. Communicating Main Ideas In what waysdoes urban sprawl reduce the quality of lifefor people in the suburbs as well as in thetown or city?

Now that you have read the chapter, take amoment to review your answers to the ReadingWarm-Up questions in your EcoLog. If necessary,revise your answers.

READING FOLLOW-UP

Rangelandand pasture

26%

Cropland20%

Urbanland6% Other

7%

Parks andpreserves

13%

Forest land28%


374 Chapter 14 Inquiry Lab

Creating a Land-Use Model Land-use plans are drawn up by planners, but they are createdwith the combined input of various members of a community.Along with three other people, you are meeting to plan the devel-opment of 400 acres of land for your growing city. Your team iscomposed of the following four members:

Procedure1. Have each team member select one of the four jobs above. 2. Use all or part of a large piece of graph paper as your map.

Mark off an area that will represent 400 square acres.Determine the approximate scale, and label the sides of yourarea accordingly.

3. The planner will color in the map as follows:a. 40 acres will be fresh water (rivers and/or lakes) and is

colored light blue.b. 80 acres will be wetlands that are right next to some of the

fresh water and are colored light purple or lavender.c. 40 acres will be land that is too sloped for building and

will be colored tan.d. 240 acres is land that is good for development and will be

colored light green.4. Once the land is colored in, it cannot be altered. That will be

the land you work with.5. After the area is colored in, the group must discuss how and

where to put the following items:a. 40 acres for a landfillb. 20 acres for utilities such as power plants, water treatment

facilities, etc.c. 40 acres for parks and wildlifed. 20 acres for housing. Try to put the houses near a

beautiful area.

Objectives� Create a simulated land-use

model.� Recognize conflicts of interest

that arise during a negotiation.� Analyze

and draw conclusions about theeffect of compromise on thedesired outcome for each inter-ested party in a land-use plan.

Materialscolored pencilsgraph paperpens

USING SCIENTIFIC METHODS

Inquiry Lab: DESIGN YOUR OWNC H A P T E R 14

Laws

• At least 10 percent of eachtype of habitat must bepreserved.

• Landfills must be at least twoacres away from all housing,wetlands and fresh water sites.

• Roads and bridges may crossrivers and wetlands but theymust go around large naturalareas.

• Roads must be connected to alldeveloped areas of the city.

• There must be no building overwetlands, slopes and freshwater. Only parks may partiallycover these habitats androads/bridges may cross them.

Team Members

• The Planner is concerned with creating a plan that encouragesthe sort of growth that will attract businesses and new citizens tothe area.

• The Developer bought the land from the city and is interested inthe right to build housing and a shopping center.

• The Conservationist is interested in preserving open space andnatural areas from further development.

• The Law Enforcer ensures that all of the laws and regulations aremet for any new development project.


Chapter 14 Inquiry Lab 375

e. 40 acres for shoppingf. 20 acres for anything that the group agrees to add. For

example, you could add a few acres for communitygardens or for sports and playing fields. The law enforcercannot suggest anything, but if the group can’t agree onwhat to add, the law enforcer may cast the deciding vote.

g. 40 acres of roads and bridges (you can divide an acre upso that you can build long, thin roads rather than createshort, fat roads that are an entire acre thick). Make sure atleast one road goes into and out of town.

6. The law enforcer should make sure that the plans abide bythe planning regulations by checking the map for violations.

7. Use the key under the map to mark which areas are which.For example, an R denotes a road or bridge. Use a pencil andwrite in the things softly at first in case changes are to bemade. You may need a second copy of the map in case youmake mistakes the first time.

Analysis 1. Describing Events Did everyone on your team agree on the

plan, or were there conflicts of interest? Explain.2. Describing Events Were you able to get everything your

team wanted into the plan or did it face any problems?Describe what happened.

3. Identifying Patterns How did the features of the land con-strain the plan that you made? Did you encounter anyproblems?

Conclusions4. Evaluating Results Does the plan your group created meet

the needs of all of the group members? Does it allow fordevelopment while preserving the environment?

5. Evaluating Models How do you think this land planning“simulation” compares to the real-life process of land-useplanning?

Sloped land Shopping area

Wetlands Housing

Fresh water

For development

Utilities

Road

� Example Map This is an exampleof what your land-use model mightlook like.

1. Research and Communications Look in the newspaper oron the Internet for a story about a land-use debate in yourarea. Identify the different members involved. Role-playwith your team to see what forces will bear on thiscontroversy.

Extension


376 Chapter 14 Making a Difference

RESTORING THE RANGEWhen Ohioan J. David Bambergerfirst moved to San Antonio, Texasas a vacuum cleaner sales represen-tative, he was charmed by the dry,grass-covered rangeland of theTexas Hill Country. But much ofthe land was degraded. It had beenovergrazed by cattle and was leftwith thin soil and dried up creeks.

Bamberger became intrigued bythe idea of restoring some of therange to its original beauty. Hewas inspired by a book his mother gave him called PleasantValley, by Louis Bromfield. Longbefore it was popular, Bromfieldhad theories about how degradedhabitats could be restored andhow they could then be managedin a sustainable manner. Bam-berger was intrigued by the idea of putting Bromfield’s theoriesinto action.

The Bamberger RanchIn 1959, David Bamberger boughthis first plot of land near JohnsonCity. Since then, David andMargaret Bamberger haveexpanded the ranch to nearly2,300 hectares (5,500 acres). It isone of the largest habitat restora-tion projects in Texas, and showsthe beauty of this area before itwas damaged by human activities.

In its natural state, the ranchshould have been grassland, withwoody shrubs only near creeks.Instead, it had become overgrownwith juniper shrubs and trees(often called cedar, Juniperusashei), which can grow in poorsoil and choke out other plants.

Bamberger read everything hecould find on the degradation andrestoration of rangeland. Hefound that two main thingsdestroy the range: overgrazing and the suppression of wildfires.

Overgrazing causes soil erosion.The lack of fires permits thegrowth of shrubs that shade outgrasses and wildflowers.

The Bambergers set to work torestore the property. They clearedmost of the junipers, which leftmore water in the soil. Theyplanted native trees, wildflowers,and grasses, and they controlledthe grazing.

Grazing is necessary for healthygrassland. The American prairieswere home to huge herds of bison(buffalo), which cropped the grassand fertilized the soil with theirdroppings. The Bambergers com-bined the grazing they needed withthe preservation of an endangeredspecies. San Antonio Zoo asked theBambergers if they could help pre-serve the endangered scimitar-horned oryx, an antelope withthin, curved horns that is native toNorth Africa. Only a few smallherds of this species remained, andthe zoo feared that the oryx werebecoming inbred, with too littlegenetic diversity. The Bambergersagreed, and the ranch is now hometo a large herd of oryx.

The Effects of RestorationThe change in the ranch sinceBamberger first bought it is mostobvious at the fence line border-ing the ranch. Beyond the fencethere is a small forest of junipersand little other vegetation. OnBamberger’s side, the main plantsare grasses and wildflowers, withshrubs and trees in canyons andgullies beside the creeks. Whenthe Bambergers first arrived, theycounted only 48 species of birdson the ranch. Now, there aremore than 150 species becausethere are many more differentplants on the ranch. In the early

days, deer on the ranch weighedonly about 20 kg. Now theyweigh about 40 kg, thanks to theimproved grazing.

In addition to deer and oryx,cattle and goats live on the ranch.Some of these are used for experi-ments on the effects of domesticanimals on rangeland. Studentsand faculty from nearby universi-ties are studying this question byusing exclosures. These are fencesthat keep large animals out of anarea. The vegetation inside anexclosure is invariably taller thanthat outside because grazing ani-mals are excluded. But in addi-tion, the plant mix inside theexclosure is different from thatoutside. This is because grazingmammals eat only a few nutritiousspecies and leave the others.

� David Bamberger, founder of theBamberger Ranch Preserve.


Chapter 14 Making a Difference 377

What Do You Think?Habitat restoration shows uswhat the land was like beforethe settlers arrived. It alsoshows us how much the landhas changed under humanmanagement. Can you thinkof any habitat in your areathat could be restored? Howwould you go about trying to restore it? What do youthink it would look like afterrestoration?

The Distribution of WaterOne important change in theranch under the Bambergers’ man-agement has been the change inwater distribution. Water is veryimportant in rangeland, whichnaturally gets little rainfall. Manyof the creeks dry up between rainyperiods, but water remains in thesoil and underground. Grasseshave spreading root systems thatabsorb water from a wide area.Poor management changes thisbalance by allowing junipers totake over the land. A juniper cantake up 10 L of water a day fromthe soil, leaving too little fornearby grasses and wildflowers tosurvive. Then, when it rains heav-

ily, the junipers cannot absorb allthe water and it runs off the land.With no grass roots to hold thesoil in place, the soil erodes intothe creeks.

When the Bambergers arrived atthe ranch, it was degraded range-land. They drilled wells 150 mdeep (500 ft) and did not reach thewater table. Now, with the restora-tion of grassland, soil erosion hasbeen reduced and much morewater remains in the soil. Creeksand lakes contain water for mostof the year, and a dry spell is not a disaster. The water in the creeksand lakes is clear and full of fish,instead of muddy because it is fullof soil.

SustainabilityThe Bamberger Ranch is a work-ing ranch, raising and selling livestock, but it is also home todozens of other projects. Bam-berger consultants advise otherswho are interested in managingrangeland in a sustainable fash-ion. Volunteers help by buildingand repairing nature trails andperforming all kinds of mainte-nance work. The ranch hostsresearch on grasslands and rangemanagement, conferences on habitat restoration, educationalworkshops, as well as vacationsfor those interested in all aspectsof nature.

� At nearly 2,300 hectares, the Bamberger Ranch is one of thelargest habitat restoration projects in Texas. This is a photo of aportion of the Bamberger Ranch used for sustainable ranching.


Documents

SECTION 3 Land Management and Conservation · Describe two ways that rangeland can be managed sustainably. Describe the environmental effects of deforestation. Explain the function