LANDLANDEnvironmental Environmental Science Ch. 14Science Ch. 14

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ObjectivesObjectives

• Distinguish between urban and rural land.

• Describe three major ways in which humans use land.

• Explain the concept of ecosystem services.

I. How We Use LandI. How We Use Land

• A. Land Use and Land Cover• We us land for many purposes

including farming, mining, recreation, and building cities and highways

• Land cover is what you find on a patch of land – it depends on how the land is used -forest, field of grain, parking lot

2 Types of Land2 Types of Land UrbanUrban land land – land that is covered mainly – land that is covered mainly

with buildings and roadswith buildings and roads

--contains 2,500 or more people and usually contains 2,500 or more people and usually has a government body like a city councilhas a government body like a city council

Any area not classified as urban is ruralAny area not classified as urban is rural Rural Rural landland – land that contains relatively – land that contains relatively

few people and large areas of open spacefew people and large areas of open space Most land provides one or more resources Most land provides one or more resources

that humans consume – table 1that humans consume – table 1

B. Where We LiveB. Where We Live Until 1850 most people lived in rural Until 1850 most people lived in rural

areas -many were farmers who grew areas -many were farmers who grew crops and raised livestock for food, crops and raised livestock for food, clothing, and manufacturingclothing, and manufacturing

others managed forests, worked in others managed forests, worked in local mines or mills, or local mines or mills, or manufactured necessities of life for a manufactured necessities of life for a towntown

The Industrial Revolution The Industrial Revolution changed this patternchanged this pattern

-machinery was built that made it possible for -machinery was built that made it possible for fewer people to operate a farm or grain millfewer people to operate a farm or grain mill

-better transportation allowed manufacturers -better transportation allowed manufacturers to be located far from their customers to be located far from their customers

-thousands of jobs in rural areas were -thousands of jobs in rural areas were eliminated so people moved to cities to find eliminated so people moved to cities to find jobsjobs

Urban areas grew rapidly in the 20th century Urban areas grew rapidly in the 20th century and spread over more landand spread over more land

-today most people in the world live in -today most people in the world live in urbanurban areasareas

-happened rapidly in developed countries -happened rapidly in developed countries between 1880 and 1950between 1880 and 1950

-now happening rapidly in developing -now happening rapidly in developing countries countries

Where We LiveWhere We Live

C. The Urban-Rural C. The Urban-Rural ConnectionConnection

Whether people live in the cities or Whether people live in the cities or countryside, they are dependent on countryside, they are dependent on the resources produced in rural the resources produced in rural areasareas

-these resources include clean -these resources include clean drinking water, fertile soil and land drinking water, fertile soil and land for crops, trees for wood and paper for crops, trees for wood and paper and much of the oxygen we breathe and much of the oxygen we breathe

Ecosystem servicesEcosystem services Ecosystem servicesEcosystem services – the resources – the resources

that are produced by natural and that are produced by natural and artificial ecosystemsartificial ecosystems -examples are listed in table 2-examples are listed in table 2

Supporting Urban areasSupporting Urban areas -area of rural land is needed to support -area of rural land is needed to support

one person depends on many factorsone person depends on many factors -the climate, standard of living, how -the climate, standard of living, how

efficiently resources are usedefficiently resources are used -each person in a developed country uses -each person in a developed country uses

the ecosystem services proved by about 8 the ecosystem services proved by about 8 hectares of land and waterhectares of land and water

Answer on Your Dry erase Answer on Your Dry erase Card for ECCard for EC

How we compareHow we compare

-in the US each person uses the -in the US each person uses the ecosystem services from more than ecosystem services from more than 12 hectares whereas each person in 12 hectares whereas each person in Germany uses about 6 hectares worthGermany uses about 6 hectares worth

-individuals in developing countries -individuals in developing countries do not have access to all the do not have access to all the resources for a healthy life – they resources for a healthy life – they may use ecosystem services from may use ecosystem services from less than a hectare of landless than a hectare of land

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ObjectivesObjectives DescribeDescribe the urban crisis, and explain the urban crisis, and explain

what people are doing to deal with it.what people are doing to deal with it. Explain Explain how urban sprawl affects the how urban sprawl affects the

environment.environment. QuestionQuestion how open spaces provide how open spaces provide

urban areas with environmental benefits.urban areas with environmental benefits. Formulate Formulate how the heat-island effect how the heat-island effect

occurs.occurs. Predict Predict how people can use the how people can use the

geographic information system as a tool geographic information system as a tool for land-use planning.for land-use planning.

PredictPredict

There are two types of land represented There are two types of land represented here, Open and Urban. One is covered here, Open and Urban. One is covered with soil and vegetation, the other is with soil and vegetation, the other is covered with impermeable material.covered with impermeable material.

Predict which will be warmer at the end of Predict which will be warmer at the end of class and record that in the margin of your class and record that in the margin of your notes.notes.

What is this phenomenon called?What is this phenomenon called?

II. Urban Land UseII. Urban Land Use A. UrbanizationA. Urbanization UrbanizationUrbanization – the movement of people – the movement of people

from rural areas to citiesfrom rural areas to cities -people leave rural areas for more plentiful -people leave rural areas for more plentiful

and better paying jobs in towns and citiesand better paying jobs in towns and cities -as urban populations have grown many -as urban populations have grown many

small towns have grown together and small towns have grown together and formed larger urban areas -called formed larger urban areas -called metropolitan areasmetropolitan areas

-Urban areas that have grown slowly are -Urban areas that have grown slowly are often relatively pleasant places to live – often relatively pleasant places to live – roads and public roads and public

transportation have been built to handle the transportation have been built to handle the growth so that traffic flows freely growth so that traffic flows freely

UrbanizationUrbanization -buildings, roads, and parking lots are mixed -buildings, roads, and parking lots are mixed

in with green spaces and recreational areasin with green spaces and recreational areas -green spaces may provide these urban areas -green spaces may provide these urban areas

with much needed ecosystem services such with much needed ecosystem services such as moderation of temperature, infiltration of as moderation of temperature, infiltration of rainwater runoff, and aesthetic valuerainwater runoff, and aesthetic value

The Urban CrisisThe Urban Crisis -when urban areas grow rapidly, they often -when urban areas grow rapidly, they often

run into troublerun into trouble -can overwhelm the infrastructure and lead -can overwhelm the infrastructure and lead

to traffic jams, substandard housing, and to traffic jams, substandard housing, and polluted air and waterpolluted air and water

GIS Views Of Seattle, WAGIS Views Of Seattle, WA

Urban NeedsUrban Needs infrastructureinfrastructure – all the things that – all the things that

a society builds for public usea society builds for public use

-roads, sewers, railroads, bridges, -roads, sewers, railroads, bridges, canals, fire and police stations, canals, fire and police stations, schools, libraries, hospitals, etc.schools, libraries, hospitals, etc.

-when more people live in a city than -when more people live in a city than its infrastructure can support the its infrastructure can support the living conditions deteriorate causing living conditions deteriorate causing an an urban crisisurban crisis

Urban sprawlUrban sprawl – the rapid expansion of a – the rapid expansion of a city into the countryside around the citycity into the countryside around the city

-building suburbs or housing and -building suburbs or housing and associated commercial buildings on the associated commercial buildings on the boundary of a larger townboundary of a larger town

-people living in the suburbs commute to -people living in the suburbs commute to work in the city by carwork in the city by car

-suburbs build on land previously used for -suburbs build on land previously used for food productionfood production

-each year in the US suburbs spread over -each year in the US suburbs spread over another 1 million hectares of landanother 1 million hectares of land

Development on Marginal Development on Marginal landslands

-many cities were first built where there -many cities were first built where there was little room for expansionwas little room for expansion

-as cities grew the suburbs were often built -as cities grew the suburbs were often built on on marginal landmarginal land –land that is poorly –land that is poorly suited for buildingsuited for building

Other Impacts of UrbanizationOther Impacts of Urbanization -cities generate and trap more heat – roads -cities generate and trap more heat – roads

and buildings trap more heat than and buildings trap more heat than vegetation does and retains heat longervegetation does and retains heat longer

-increased temperature in a city is called a -increased temperature in a city is called a heat islandheat island

-heat islands can affect local weather -heat islands can affect local weather patternspatterns

What Is an Urban Heat What Is an Urban Heat Island?Island?

As urban areas develop, changes As urban areas develop, changes occur in their landscape. Buildings, occur in their landscape. Buildings, roads, and other infrastructure roads, and other infrastructure replace open land and vegetation. replace open land and vegetation. Surfaces that were once permeable Surfaces that were once permeable and moist become impermeable and and moist become impermeable and dry. These changes cause urban dry. These changes cause urban regions to become warmer than their regions to become warmer than their rural surroundings, forming an rural surroundings, forming an "island" of higher temperatures in the "island" of higher temperatures in the landscapelandscape

Why Do We Care About Why Do We Care About Heat Islands?Heat Islands?

Elevated temperature from urban heat Elevated temperature from urban heat islands, particularly during the summer, islands, particularly during the summer, can affect a community's environment can affect a community's environment and quality of life. While some heat and quality of life. While some heat island impacts seem positive, such as island impacts seem positive, such as lengthening the plant-growing season, lengthening the plant-growing season, most impacts are negative and include:most impacts are negative and include: More energy used for coolingMore energy used for cooling Promotes ground level ozonePromotes ground level ozone Thermal water pollutionThermal water pollution

How do we prevent the How do we prevent the Urban Heat Island Urban Heat Island

increasing increasing tree and vegetative cover creating creating green roofs (also called (also called

"rooftop gardens" or "eco-roofs") "rooftop gardens" or "eco-roofs") installing installing

cool—mainly reflective—roofs using using cool pavements..

B. Urban PlanningB. Urban Planning Land-use planningLand-use planning – determining – determining

in advance how land will be usedin advance how land will be used -where houses, businesses, and -where houses, businesses, and

factories will be built, where land factories will be built, where land will be protected for recreation, etc.will be protected for recreation, etc.

-land use planners determine the -land use planners determine the best locations for shopping malls, best locations for shopping malls, sewers, electrical lines, and other sewers, electrical lines, and other infrastructureinfrastructure

-making land-use plans is a -making land-use plans is a complex and controversial complex and controversial processprocess

-federal, state, and local -federal, state, and local developers prepare detailed developers prepare detailed reports assessing the reports assessing the environmental impact of any environmental impact of any projectsprojects

-developers, city governments, -developers, city governments, local businesses, and citizens local businesses, and citizens often disagree about land-use often disagree about land-use plansplans

Technological ToolsTechnological Tools -land use planners have -land use planners have

sophisticated methods and sophisticated methods and tools available for them tools available for them

(GIS)(GIS) Geographic information system (GIS)Geographic information system (GIS) – a – a

computerized system for storing, manipulating, computerized system for storing, manipulating, and viewing geographic dataand viewing geographic data

-GIS software allows a user to enter different -GIS software allows a user to enter different types of data about an area and create maps – types of data about an area and create maps – uses GPSuses GPS

TransportationTransportation -most cities in the US are difficult to travel in -most cities in the US are difficult to travel in

without a carwithout a car -many cities have a -many cities have a mass transit systemmass transit system – have – have

been constructed to get people where they want been constructed to get people where they want to goto go

-Mass transit is a planning solution that saves -Mass transit is a planning solution that saves energy, reduces highway congestion, reduces air energy, reduces highway congestion, reduces air pollution, and limits the loss of land to roadways pollution, and limits the loss of land to roadways and parking lotsand parking lots

Wide Open SpacesWide Open Spaces Open spaceOpen space – land within an urban area set – land within an urban area set

aside for scenic and recreational enjoymentaside for scenic and recreational enjoyment -parks, public gardens, bicycle and hiking -parks, public gardens, bicycle and hiking

trailstrails GreenbeltsGreenbelts – open spaces left in their natural – open spaces left in their natural

condition condition

-provide important ecological services-provide important ecological services Have plants that absorb carbon dioxide, Have plants that absorb carbon dioxide,

produce oxygen, and filter out pollutants from produce oxygen, and filter out pollutants from air and water, keep the city cooler, reduce air and water, keep the city cooler, reduce drainage problems by absorbing more drainage problems by absorbing more rainwater runoff resulting in less floodingrainwater runoff resulting in less flooding

provide places for exercise and relaxationprovide places for exercise and relaxation

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ObjectivesObjectives

ExplainExplain the benefits of preserving the benefits of preserving farmland.farmland.

DescribeDescribe two ways that rangeland two ways that rangeland can be managed sustainably.can be managed sustainably.

DescribeDescribe the environmental effects the environmental effects of deforestation.of deforestation.

ExplainExplain the function of parks and of the function of parks and of wilderness areas.wilderness areas.

III. Land Management and III. Land Management and ConservationConservation

As human populations grow, the resources As human populations grow, the resources of more rural land are needed to support of more rural land are needed to support the populationthe population

The main categories of rural land are The main categories of rural land are farmland, rangeland, forest land, national farmland, rangeland, forest land, national and state parks, and wildernessand state parks, and wilderness

-we have reduced their productivity by -we have reduced their productivity by overusing or polluting themoverusing or polluting them

-condition of rural land is important -condition of rural land is important because of the ecological services that it because of the ecological services that it providesprovides

A. FarmlandsA. Farmlands Farmland is land that is used to grow Farmland is land that is used to grow

crops and fruitcrops and fruit -urban development in some places -urban development in some places

threatens some of the most productive threatens some of the most productive farmlandfarmland

-in 1996, the US government established -in 1996, the US government established a national Farmland Protection Program a national Farmland Protection Program to help state, county, and to help state, county, and

local governments protect farmland in local governments protect farmland in danger of being developed danger of being developed

B. RangelandsB. Rangelands RangelandRangeland – land that supports – land that supports

different vegetation types like different vegetation types like grasslands, shrublands, and deserts grasslands, shrublands, and deserts that is not used for farming or timber that is not used for farming or timber productionproduction

-can be arid or wet-can be arid or wet -most common use of rangelands is for -most common use of rangelands is for

the grazing of livestock like cattle, the grazing of livestock like cattle, sheep, goats which are valued for their sheep, goats which are valued for their meat, milk, wool, and hidesmeat, milk, wool, and hides

-native wildlife species also graze this -native wildlife species also graze this landland

-necessary for maintaining the world’s -necessary for maintaining the world’s food supplyfood supply

Problems on the RangeProblems on the Range -rangelands in the US have become degraded -rangelands in the US have become degraded

by poor land management strategiesby poor land management strategies --overgrazingovergrazing – allowing more animals to – allowing more animals to

graze in an area than the range can support -graze in an area than the range can support -cause most damage to rangelandscause most damage to rangelands

-when animals overgraze, too many of the -when animals overgraze, too many of the plants are eaten and the land can become plants are eaten and the land can become degraded -less desirable plant species may degraded -less desirable plant species may invade the area and replace more desirable invade the area and replace more desirable plant species -in severe cases all vegetation is plant species -in severe cases all vegetation is eateneaten

-once the plants are gone there is nothing to -once the plants are gone there is nothing to keep the soil from eroding leading to keep the soil from eroding leading to DesertificationDesertification

Maintaining the RangeMaintaining the Range -much of the rangeland in the US is public land -much of the rangeland in the US is public land

managed by the federal government which leases managed by the federal government which leases the the

rangeland to ranchersrangeland to ranchers -much of it is degraded-much of it is degraded -1978 Public Rangelands Improvement Act – -1978 Public Rangelands Improvement Act –

enacted to reverse this trend and improve land enacted to reverse this trend and improve land management management

practicespractices -sustaining the productivity of the rangeland -sustaining the productivity of the rangeland

generally means reducing overgrazing by limiting generally means reducing overgrazing by limiting herds to sizes herds to sizes

that do not degrade the landthat do not degrade the land

Rotational GrazingRotational Grazingmay be left unused for periods of time so that may be left unused for periods of time so that

the vegetation can recoverthe vegetation can recover -improving rangeland that has been -improving rangeland that has been

damaged includesdamaged includes -killing invasive plants and planting native -killing invasive plants and planting native

vegetationvegetation -fencing areas to let them recover-fencing areas to let them recover -ranchers dig several small water holes so -ranchers dig several small water holes so

that livestock to not overgraze around a that livestock to not overgraze around a single water holesingle water hole

C. Forest LandsC. Forest Lands Trees are harvested to proved products we use Trees are harvested to proved products we use

every day, paper, furniture, lumber and plywood for every day, paper, furniture, lumber and plywood for homehome

-forest products such as maple syrup and turpentine-forest products such as maple syrup and turpentine -one of the most important services is the removal of -one of the most important services is the removal of

CO2 from the airCO2 from the air

Harvesting TreesHarvesting Trees -people use enormous amounts of wood-people use enormous amounts of wood -each person in the US uses 3.5 times the worldwide -each person in the US uses 3.5 times the worldwide

average of 1,800 cm3 per person each dayaverage of 1,800 cm3 per person each day -each person cutting down a tree 30m tall every year-each person cutting down a tree 30m tall every year

TreesTrees developing nation individuals depend on developing nation individuals depend on

firewood as their main source of fuelfirewood as their main source of fuel -timber industry classifies forest lands into -timber industry classifies forest lands into

three categoriesthree categories -virgin forest – a forest that has never -virgin forest – a forest that has never

been cutbeen cut -native forest – forest that is planted and -native forest – forest that is planted and

managedmanaged -tree farms – areas where trees are -tree farms – areas where trees are

planted in rows and harvested like other planted in rows and harvested like other cropscrops

two most widely-used two most widely-used methods of tree harvesting methods of tree harvesting

are are --clear cuttingclear cutting – process of removing all – process of removing all

the trees in an area of land -destroys the trees in an area of land -destroys established wildlife habitat and causes established wildlife habitat and causes soil erosionsoil erosion

--selective cuttingselective cutting – process of cutting – process of cutting and removing only middle-aged or mature and removing only middle-aged or mature treestrees

-more expensive than clear cutting but -more expensive than clear cutting but much less destructivemuch less destructive

Harvesting TreesHarvesting Trees

DeforestationDeforestation DeforestationDeforestation – the clearing of trees – the clearing of trees

from an area without replacing themfrom an area without replacing them -countries become severely deforested -countries become severely deforested

as populations expand and the as populations expand and the demand for forest products increasesdemand for forest products increases

-forests are cleared to convert land -forests are cleared to convert land into farmland or to make space for into farmland or to make space for roads, homes, factories, and office roads, homes, factories, and office buildingsbuildings

-deforestation reduces wildlife habitat-deforestation reduces wildlife habitat

DeforestationDeforestation -causes soil erosion – there are not tree -causes soil erosion – there are not tree

roots to hold the soil in place and it is roots to hold the soil in place and it is easily washed or blown awayeasily washed or blown away

-rate of deforestation is high in tropical -rate of deforestation is high in tropical rain forests where the soil is relatively rain forests where the soil is relatively thinthin

-farmers who clear forests in these areas -farmers who clear forests in these areas must always move from one plot of land to must always move from one plot of land to another and clear more forest each time another and clear more forest each time they movethey move

-whether cleared for farming or wood, if -whether cleared for farming or wood, if trees are not replanted natural resources trees are not replanted natural resources are steadily depletedare steadily depleted

ReforestationReforestation ReforestationReforestation – the process by which – the process by which

trees are planted to re-establish trees that trees are planted to re-establish trees that have been cut down in forest landhave been cut down in forest land

-in some places reforestation is happening -in some places reforestation is happening faster than trees are being cut down – New faster than trees are being cut down – New EnglandEngland

-some governments require reforestation -some governments require reforestation after timber has been harvestedafter timber has been harvested

-private organizations have established -private organizations have established tree-planting programs on roadsides in tree-planting programs on roadsides in citiescities

ReforestationReforestation

D. Parks and PreservesD. Parks and Preserves In 1870, the first national park was In 1870, the first national park was

established – Yellowstone National Parkestablished – Yellowstone National Park -today, the US has about 50 national parks-today, the US has about 50 national parks

Public lands have many purposesPublic lands have many purposes -most are not protected as national parks-most are not protected as national parks -leased to private companies for logging, -leased to private companies for logging,

mining, and ranchingmining, and ranching -maintained for hunting and fishing or as -maintained for hunting and fishing or as

wildlife refuges or for protecting wildlife refuges or for protecting endangered speciesendangered species

International efforts have set up several International efforts have set up several hundred hundred biosphere reservesbiosphere reserves around the around the worldworld

– – include people in their management planinclude people in their management plan

WildernessWilderness Under the US Wilderness Act of 1964, Under the US Wilderness Act of 1964,

designated certain lands as wilderness designated certain lands as wilderness areasareas

WildernessWilderness – an area in which the land – an area in which the land and the ecosystems it supports are and the ecosystems it supports are protected from all exploitationprotected from all exploitation

-open to hiking, fishing, boating (without -open to hiking, fishing, boating (without motors), and campingmotors), and camping

-building roads or structures and using -building roads or structures and using motorized equipment are not allowedmotorized equipment are not allowed

Parks & PreservesParks & Preserves

Benefits of Protected AreasBenefits of Protected Areas -without national and private parks -without national and private parks

and preserves around the world, and preserves around the world, many more species would be extinctmany more species would be extinct

-provide recreation for people-provide recreation for people -only place where unspoiled forests, -only place where unspoiled forests,

deserts, or prairies remaindeserts, or prairies remain -serve as outdoor classrooms and -serve as outdoor classrooms and

research labs where people can research labs where people can learn more about the natural worldlearn more about the natural world

Threats to protected areasThreats to protected areas -constant battle between our -constant battle between our

conservation efforts and the conservation efforts and the growing populationgrowing population

-litter and traffic jams, rangelands, -litter and traffic jams, rangelands, mining, logging, oil and gas drilling mining, logging, oil and gas drilling operations, factories, power plants, operations, factories, power plants, and urban areas are often close and urban areas are often close enough to the park to affect themenough to the park to affect them

-preserved areas are affected by -preserved areas are affected by climate change and air and water climate change and air and water pollutionpollution

Threats to protected areasThreats to protected areas

-wilderness areas have limits to -wilderness areas have limits to the number of people permitted the number of people permitted in some areas if at allin some areas if at all

-volunteer programs to pick up -volunteer programs to pick up trash, build trails, control trash, build trails, control invading or exotic species, and invading or exotic species, and educate the visiting publiceducate the visiting public