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APES REVIEW
Chapter 23
1. Definitions
Old Growth Forests- uncut forests or regenerated forests that have not been seriously
disturbed by human activities or natural disasters for at least several hundred years
Second Growth Forests- stands of trees resulting from secondary ecological succession
after the trees in tan area have been removed by human activities such as clear cutting for
timber or conversion to cropland or natural forces such as fire, hurricanes, or volcanic
eruption
Tree Plantations/ Tree Farms- managed tracts with uniformly aged trees of one species
that are harvested by clear cutting as soon as they become commercially valuable
Even Aged Management- involves maintaining trees in a given stand at about the same
age and size
Uneven-aged Management- involves maintaining a variety of tree species in a stand at
many ages and sizes to foster natural regeneration
Selective cutting- intermediate ages or mature trees in an uneven aged forest are cut
singly or in small groups
Shelterwood Cutting- which removes all mature trees in two or three cuttings over a
period of about 10 years
Seed Tree Cutting- harvests nearly all a stand’s trees in one cutting, leaving a few
uniformly distributed seed producing trees to regenerate the stand
Clear Cutting- removes all of the trees from an area in a single cutting
Strip Cutting- clear cutting variation that can allow a sustainable timber yield without
widespread destruction
3. Major Uses of Land
World: Forest, Rangeland and Pasture, Desert, Cropland, Tundra and Wetlands, Urban
United States: Forest, Rangeland and Pasture, Croplands, Desert and Tundra and
Wetlands, Parks and Wildlife Refuge and Wilderness, Urban
4. Federal Lands in United States
35% of United States land is managed by the Federal Government.
The five major types of public lands that the US controls are:
 Oil Reserves
 Coal reserves
 Natural gas reserves
 Commercial forests
 Hard rock minerals
Four Principles that govern use of public land:
- Protecting biodiversity, wildlife habitats and ecological functioning of
ecosystems
-No one should receive subsidies of tax breaks for using or extracting
resources on public land
-The American people deserve fair compensation for the use of their
property
-All users or extractors of resources on public lands should be fully
responsible for any environmental damage they cause.
8. Old Growth v. Second Growth v. Tree Plantations
Old Growth Forests- uncut forests or regenerated forests that have not been seriously
disturbed by human activities or natural disasters for at least several hundred years
Second Growth Forests- stands of trees resulting from secondary ecological succession
after the trees in tan area have been removed by human activities such as clear cutting for
timber or conversion to cropland or natural forces such as fire, hurricanes, or volcanic
eruption
Tree Plantations/ Tree Farms- managed tracts with uniformly aged trees of one species
that are harvested by clear cutting as soon as they become commercially valuable
10. Harvesting Trees
Selective cutting- intermediate ages or mature trees in an uneven aged forest are
cut singly or in small groups
Shelterwood Cutting- which removes all mature trees in two or three cuttings
over a period of about 10 years
Seed Tree Cutting- harvests nearly all a stand’s trees in one cutting, leaving a
few uniformly distributed seed producing trees to regenerate the stand
Clear Cutting- removes all of the trees from an area in a single cutting
Strip Cutting- clear cutting variation that can allow a sustainable timber yield
without widespread destruction
Advantages of Selective Cutting Reduces crowding
 Encourages growth of younger trees
 Maintains an uneven aged stand of trees of different species
 Allows natural regeneration from the surrounding trees
 Can help protect site from soil erosion and wind damage
 Can be used to remove diseased trees
 Allows a forest to be used for multiple purposes
Disadvantages of Selective Cutting High Grading- cutting and removing only the largest and best specimens of
the most desirable species
o Reduction of forest canopy
Advantages of Clear Cutting Increases timber yield per hectare
 Permits reforesting trees with genetically improved stocks of fast growing
trees
 Shortens the time needed to establish a new stand of trees
 Takes less skill and planning than other harvesting methods
 Usually provides the maximum economic return in the shortest time
 Often is the best way to harvest tree plantations and stands of some tree
species that need full or moderate sunlight for growth
Disadvantages of Clear Cutting Leaves moderate to large forest openings
 Eliminates most recreation value for several decades
 Reduces biodiversity, disrupts ecosystem processes and destroys and
fragments some wildlife habitats
 Makes nearby trees more vulnerable to being blown down by windstorms
 Leads to severe soil erosion, sediment water pollution and flooding when done
on steep slopes
14. Forest Fires
Surface Fires- burn only undergrowth and leaf litter on the forest floor
Crown Fires- may start on the ground but eventually burn whole trees and leap
from treetop to tree top.
Ground Fires- surface fires that go underground and burn partially decayed leaves
or peat.
Benefits- some fires burn away flammable ground material and help prevent more
destructive fires, release vulnerable mineral nutrients tied up in slowly
decomposing litter and undergrowth, increase the activity of underground
nitrogen fixing bacteria, stimulate germination of certain tree seeds, and help
control pathogens and insects
Pros of Prescribed Fires:
 Keep down flammable ground litter in fire adapted forests as part of the
natural ecological cycle of succession and regeneration
Cons of Prescribed Fires:
 Require careful planning and monitoring to keep them from getting out of
control
Pros/Cons of Allowing Natural Fires to Burn:
 They have been allowed as long as they do not threaten human lives, park or
forest service facilities, private property, or endangered wildlife.
Pros/Cons of Cutting Trees to Thin Forests:
 Promoted by Logging Companies
 Increase chances of severe fires:
o Most dangerous fuel is unwanted waste material or slash left behind
after a forest is cut.
o Will not reduce the fire hazard because larger are difficult to ignite.
Shrubs and small trees fuel most fires.
28. Fuelwood Crisis
Fuelwood Crisis- crisis because a lot of people in developing countries are not
getting enough fuelwood to meet basic needs
Developing Countries can reduce the severity of fuelwood crisis by:
Planting more growing fuelwood trees or shrubs
Burning wood more efficiently
Switching to other fuels
33. Nature Reserve System
-It should contain a mixture of large and small reserves because it can protect a
variety of species and communities against a number of different threats.
-The best shape for a nature reserve us a circular reserve because the circular
shape allows better protection of the interior area that is further away from the
edges of the reserve.
-Pros and cons of establishing large reserves or several small reserves:
Large Reserves:
-Only way to maintain viable populations of large, wide ranging
populations such as panthers, elephants and grizzly bears
-Sustain more species base on the species area curve
-Minimize the area of outside edges exposed to natural disturbances,
invading species, and human disturbances from nearby developed areas
-Provide greater habitat diversity than small reserves
Several well placed medium sized:
-Variety of habitats and thus preserve more biodiversity than a single large
reserve of the same area
-May better protect more populations of endemic species with small
ranges than a single large reserve
-Are less likely to be simultaneously devastated, by a single even such as a
flood, fire, disease, or invasion by a nonnative species than a singe large
reserve.
-It is better to have a heterogeneous reserve with a variety of habitats than a
homogenous reserve because nature is rarely at equilibrium state and undergoes
continuous change. A heterogeneous reserve provides a variety of habitat patches
(patch dynamics) of different sizes, shapes, and successional stages and can allow
species in disturbed patches to move to undisturbed patches.
-Pros and Cons of establishing corridors between nature reserves:
+Help support more species
+Allow migration of vertebrates that need large ranges
+Permit migration of individuals and populations when environmental
conditions in a reserve deteriorate
+Help preserve animals that must make seasonal migrations to obtain food
+Enable some species to shift their ranges if global warming makes their
current ranges uninhabitable
-Threaten once isolated populations by allowing the movement of pest
species, disease, fire and exotic species between reserves
-Increase exposure of migrating species to natural predators, human
hunters and pollution
-Costly to acquire, protect, and manage
37. Wilderness
Wilderness: Areas of undeveloped land affect primarily by the forces of nature
when man is a visitor who does not remain.
Importance: We need wild places where people can experience the beauty
of nature and observe natural biological diversity, and enhance their
mental and physical health by getting away from noise, stress,
development, and large numbers of people.
Pros and Cons of protecting more wilderness:
+Provide mostly undisturbed habitats for wild plants and animals,
especially those that need a large range
+Help protect diverse biomes from damage
+Provide a natural laboratory in which we can discover more about how
nature works in the few remaining areas not seriously disturbed by human
activities.
Three Ways to manage wilderness:
1) Easily accessible, popular areas that have trails, bridges, hikers’ huts,
outhouse, assigned campsites, and extensive ranger patrols
2) Large, remote wilderness areas used only by people who get a permit
by demonstrating their wilderness skills
3) Undisturbed biologically unique areas with no human entry allowed
38. Ecological Restoration
Restoration: involves trying to return a particular degraded habitat or ecosystem
to a condition as similar as possible to its pre-degraded state.
Rehabilitation: involves any attempt to restore at least some of a degraded
system’s natural species and ecosystem functions
Replacement: involves replacing a degraded ecosystem with another type of
ecosystem.
Four basic steps in carrying out ecological restoration or rehabilitation:
-Mimic nature and natural processes and let nature do most of the work,
wherever possible
-Recreate important ecological niches that have been lost
-Rely on pioneer species and natural ecological succession to facilitate the
restoration process
-Control or remove harmful species
Five techniques for implementing these steps:
-Identify what caused the degradation
-Eliminate or sharply reduce these factors (reduce toxic soil pollutants,
adding nutrients to deplete soil, adding new topsoil and eliminating
disruptive nonnative species)
-Reintroduce species to restore natural ecological processes, if necessary
-Protect the area from further degradation and from the disruptive effects
of fires
-Monitor restoration efforts, assess success, and use adaptive ecosystem
management to modify strategies as needed.
APES chapter 24
6. Commercial Fishing
Commercial marine fishing can be viewed as a tragedy of the commons because
the fish will become over-fished and then there will be no source of food for that
specific community, and will also decrease fish production as a whole. We have
to make sure that we make fishing a sustainable job.
7. Threat to wetlands
Purple Loosestrife is considered a threat if it invades the wetlands because
It has no natural enemies in the United States and has now spread to 35 states in
the US and reduces wetland biodiversity by displacing native vegetation.
19. Ways to prevent over fishing and protect marine biodiversity:
Enacting fishery regulations: set, monitor, and enforce fishery catch limits well
below their estimated maximum sustained yields. Divide up fishing quotas based
on fairness and inputs for local communities and fishers. Require selective gear
that avoids catching unwanted undersized fish.
Economic Approaches: Sharply reduce of eliminate fishing subsidies; impose fees
for harvesting fish and shellfish from publicly owned and managed offshore
waters and use the money for government fishery management; certify sustainable
fisheries
Bycatch: Reduce bycatch levels by using wider mesh nets to allow smaller species
and smaller individuals of that targeted species to escape, outfitting trawling nets
with devices to exclude seabirds and sea turtles, having observers on fishing
vessels, licensing boats to catch several species instead of only one target species,
and enacting laws that prohibit throwing edible and marketable fish back into sea.
Protected Areas: Establish no fishing marine areas, seasonal fisher closures and
marine protected areas to allow depleted fish species to recover; start by
protecting marine habitats that are in food condition or those most likely to
benefit form protection instead of using limited funds to protect potentially
hopeless cases; strengthen commitment to marine biodiversity protection and
integrated coastal management programs that promote both sustainable fishing
and the ecological health of marine ecosystems.
Nonnative Invasions: Reduce invasions by nonnative species by using heat,
disinfectants or pumping nitrogen gas to kill organisms in ship ballast water,
developing filters to trap the organisms when ballast water is take into or
discharged from a ship, and requiring ships to dump their ballast water at least
200 miles from shore and replace it with deep sea water.
Consumer Information: Use labels that allow consumers to identify fish that have
been harvested sustainability
Aquaculture: Restrict location of fish farms to reduce loss of mangrove forests
and other threatened coastal environments; enact and enforce stricter pollution
regulations for aquaculture operations; increase production of herbivorous
aquaculture fish species that need little or no grain or fish meal in diets.
20. Wetland Policy in US
Pros:
 Federal permit is required to fill or to deposit dredged or fill material into
wetlands occupying more than 3 acres
 This law as helped cut the average annual wetland loss by 80%
Cons:
 Attempts to weaken it by using unscientific criteria to classify areas as
wetlands
 8% of remaining inland wetlands are under federal protection
 Protection is weak
21. Sustaining and Restoring Wetlands
 Enacting and Enforcing laws to protect existing wetlands from destruction
and degradation
 Using comprehensive land use planning to steer developers, farmers and
resource extractors away from existing wetlands
 Using mitigation banking only as a last resort
 Requiring creation and evaluation of a new wetland before destroying an
existing one
 Restoring degraded wetlands
 Trying to prevent and control invasions by nonnative species
23. Florida’s Everglades
Problems:
 Natural flow of everglades have been disrupted and diverted with canals,
levees and spillways
 Has 56 endangered or threatened species
 Runoff from farms has stimulated growth of cattails that have taken over
Efforts to deal with problem:
 Everglade National Park
 Worlds largest ecological restoration project- carried out between
2000- 2038
o Restore curving flow of river
o Remove 250 miles of canals and levees
o Allow 240 acres of farmland to flood
o Add land to park
o Create artificial marshes
o Create 18 reservoirs
APES chapter 25
1. Definitions
Urban or Metropolitan Area- town or city plus its adjacent suburban fringe
Rural Area- area with population less than 2,500
Degree of Urbanization- percentage of its population living in an urban area
Urban growth- rate of increase of urban populations
Village- consists of a group of rural households linked together by custom,
culture and family ties
City- a much larger group of people with a variety of specialized occupations
who depend on a flow of resources from other areas to meet most of their needs
and wants
Urban Heat Island- the enormous amounts of heat generated by cars, factories
furnaces, lights, air conditioners, and heat absorbing dark roofs and roads in cities
Ecological Land Use Planning- anticipating a regions present and future needs
and problems
Zoning- various parcels of land are designated for certain uses
3.
Urban or Metropolitan Area- town or city plus its adjacent suburban fringe
Rural Area- area with population less than 2,500
Degree of Urbanization- percentage of its population living in an urban area
Urban growth- rate of increase of urban populations
Village- consists of a group of rural households linked together by custom,
culture and family ties
City- a much larger group of people with a variety of specialized occupations
who depend on a flow of resources from other areas to meet most of their needs
and wants
4. Factors that Push/pull people to urban places:
Push:
 Poverty
 Lack of land
 Declining agricultural jobs because of the increase of machines
 Famine
 War
Pull:
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




Jobs
Food
Housing
Better life
Entertainment
Freedom
7. Major problems of urban poor:
 Lacking clean water supplies, sewers, electricity and roads
 Land is not suitable for human habitation
 They do not have drinking water, sanitation facility, housing, food, health care,
schools or jobs
 Rampant disease
 Cities bulldoze slums to build up
9. Good News:
 Since 1920, many of the worst economic problems have been reduced
 Most people have better working and housing conditions; air and water quality
have been improved
 Better sanitation, water supplies and medical care have reduced death rates and
sickness
 Concentrating people in urban areas have protected countries biodiversity
Bad News:
 Number of cities in Us have deteriorating services, aging infrastructures, budget
crunches and rising poverty
 Urban sprawl is encouraging dependence on cars
10. Urban Sprawl
Definition: growth of low density development on the edges of cities and towns that
encourages dependence on cars
Factors promoting it:
 Ample land for expansion
 Federal government loans guarantees for new single family homes for
WWII veterans
 Federal and state government funding of highways that encourage
development of the once inaccessible outlying tracts of land
 Low cost of gas
 Greater availability of mortgages
 State and local zoning laws that require large residential lots
Harmful Effects:
 Increased water runoff
 Contaminated air and water
 Higher taxes
 Increased energy use
12. Seven Benefits of Urbanization
 Lower infant mortality rates
 Better access to medical care, family planning, education
 Reducing fertility and slowing population growth
 Recycling more feasible
 Per capita expenditures on environmental protection are higher
 47% of urban people occupy 2% of land

Preserve biodiversity
Harmful Effects
 Not self sustaining
 Consumer 75% of earths resources
 Fertile soil and wildlife lost as cities expand
 Lack of trees
 Produce little of their own food
 Water resource problems
 Pollution
 Noise pollution
 Microclimate- urban heat island
15. Four ways cities can grow more food
 Planting community gardens
 Using window boxes and balcony planters
 Creating gardens and greenhouses on roofs
 Raising fish in aquaculture
Urban Heat Island- the enormous amounts of heat generated by cars, factories furnaces,
lights, air conditioners, and heat absorbing dark roofs and roads in cities
Four ways to counteract heat island:
 Planting trees
 Using lighter colored paving and building surfaces
 Reducing imputes of waste heat into atmosphere
 Establishing gardens on roofs or large buildings
Five ways to reduce noise pollution
 Modifying noisy activities and devices to produce less noise
 Shielding noisy devices
 Moving noisy operations
 Using anti noise- cancels noise out with another noise
 Shielding workers from noise
19. Critical, Brazil- model of environmentally sustainable and livable city
Sustainable because:
 Lots of trees- cant cut without a permit
 City is not build around cars
o Transportation planning
 Buses, bike paths
 High rise buildings must have shops in lower 2 floors to reduce peoples
need to travel
 Recycling
 Existing buildings are reused
 Stiff air and water pollution laws
 Old buses- traveling technical schools for poor
 School children have to study ecology
 Signs along road to present environmental ideas

Each poor family is given a plot of land
25. Ways to preserve open space:
 Small or medium size parks when cities expand
 Buy land for use as parks
 Purchase development rights- prohibit certain types of development on
environmentally sensitive land
 Surround city with green belt- an open area used for recreation, sustainable
forestry or other nondestructive uses
 urban growth boundary- line surrounding city beyond which development is not
allowed
 cluster development- high density housing units are concentrated on one portion
of a parcel, rest of land is for community shared space
 greenways- biking, hiking and jogging paths
26. New cities and towns can take the pressure off of overpopulated cities and allow
development of more environmentally sustainable cities.
Tapiola, Finland: ecological design, beauty and high quality of life
Built in 7 sections
 villages separated by greenbelts
o several neighborhoods clustered around shopping and
cultural centers
o walkways
o factories located away from villages