Download Ch 18 Introduction to Ecology

Name
Date
Period
Ecology Unit
ANCHORS
 Describe ecological levels of organization in the biosphere
o Describe the levels of ecological organization (i.e., organism, population,
community, ecosystem, biome, and biosphere)
o Describe characteristic biotic and abiotic components of aquatic and
terrestrial ecosystems
 Describe interactions and relationships in an ecosystem
o Describe how energy flows through an ecosystem (e.g., food chains, food
webs, energy pyramids)
o Describe biotic interactions in an ecosystem (e.g., competition, predation,
symbiosis)
o Describe how matter recycles through an ecosystem (i.e., water cycle,
carbon cycle, oxygen cycle, and nitrogen cycle)
o Describe how ecosystems change in response to natural and human
disturbances (e.g. climate changes, introduction of nonnative species,
pollution, fires)
o Describe the effects of limiting factors on population dynamics and potential
species extinction
VOCABULARY
Abiotic
A term that describes a nonliving factor in an ecosystem.
Agriculture
The artificial cultivation of food, fiber, and other goods by the
systematic growing and harvesting of various organisms.
Aquatic
A term that describes an organism associated with a water
environment.
Biochemical
Conversion
The changing of organic matter into other chemical forms such as fuels.
Biogeochemical The movement of abiotic factors between the living and nonliving
Cycles
components within ecosystems; also known as nutrient cycles (i.e.,
water cycle, carbon cycle, oxygen cycle, and nitrogen cycle).
Biome
A large area or geographical region with distinct plant and animal
groups adapted to that environment.
Biosphere
The zone of life on Earth; sum total of all ecosystems on Earth.
A term that describes a living or once‐ living organism in an ecosystem.
Biotic
Community
(Ecological)
Different populations of organisms interacting in a shared environment.
Competition
When individuals or groups of organisms compete for similar resources
such as territory, mates, water, and food in the same environment.
Consumer
(Ecological)
An organism that obtains energy by feeding on other organisms or their
remains.
Decomposer
An organism that obtains nutrients by consuming dead and decaying
organic matter which allows nutrients to be accessible to other
organisms.
Ecology
The study of the relationships between organisms and their interactions
with the environment.
Ecosystem
A system composed of organisms and nonliving components of an
environment.
Endemic Species A species that is found in its originating location and is generally
restricted to that geographic area.
Endosymbiosis
A theorized process in which early eukaryotic cells were formed from
simpler prokaryotes.
Energy Pyramid
A model that illustrates the biomass productivity at multiple trophic
levels in a given ecosystem.
Energy
Transformation
A process in which energy changes from one form to another form
while some of the energy is lost to the environment.
Environment
The total surroundings of an organism or a group of organisms.
Food Chain
A simplified path illustrating the passing of potential chemical energy
(food) from one organism to another organism.
Food Web
A complex arrangement of interrelated food chains illustrating the flow
of energy between interdependent organisms.
Habitat
An area that provides an organism with its basic needs for survival.
Isolating
Mechanisms
Features of behaviors, morphology, or genetics which serve to prevent
mating or breeding between two different species (e.g., temporal
isolation, in which individuals are active at different times of the day,
seasons, or mating periods; ecological isolation, in which individuals
only mate in their specific habitat; behavioral isolation, when there are
no sexual cues between representatives of the species; mechanical
isolation, when there is no sperm transfer during an attempted mating;
and gametic incompatibility, when there is sperm transfer without
fertilization occurring). If mating can take place, there are four factors
that prevent hybrid viability: zygotic mortality (fertilization but no
zygote),hybrid non-viability (embryo is not viable), hybrid sterility
(resulting adult is sterile), and hybrid breakdown (first generation is
viable but future generations are not).
Limiting Factor
Chemical or physical factor that limits the existence, growth,
abundance, or distribution of an individual organism or a population.
Nonnative
Species
A species normally living outside a distribution range that has been
introduced through either deliberate or accidental human activity; also
can be known as introduced, invasive, alien, non-indigenous, or exotic.
Population
A group of individuals of the same species living in a specific
geographical area and reproducing.
18 – 1 Introduction to Ecology
Pages 359-362
 Ecology – study of interactions between organisms and the living and non-living
components of their environment
All species in a given area are interdependent, meaning that any change in the
surrounding of that area can spread through a network of interactions and affect
organisms that appear far removed from the change

Levels of organization:
1. Species – a group of organisms that
can breed and produce fertile
offspring
2. Population – groups of individuals
that are the same species and living in
the same area
3. Community – all of the living
populations in an area
4. Ecosystem - all the populations living
together with the nonliving
environment (living + nonliving
components)
5. Biomes – groups of similar
ecosystems that have similar climates
and similar communities
6. Biosphere - combines all the parts of
the earth in which life exists
18-2 Ecology of Organisms
Pages 363-365
A. Ecosystem Components
1. Abiotic – the nonliving components of an ecosystem

Sunlight (affects photosynthesis), temperature (affects metabolism),
water supply, oxygen supply, minerals, soil/rocks, pH
2. Biotic – the living components of an ecosystem

Ex: Plants, Animals, Protists, Fungi, Bacteria
B. The Niche
1. Habitat - the physical area in which an organism lives (includes climate,
topography, soil and water chemistry, plant and animal life, etc.)
2. Niche – the way of life of a species (includes its habitat, feeding habits,
reproductive behavior, etc.)
18-3 Energy Transfer
Pages 366-369
A. Producers (Autotrophs): organisms that can capture energy and use it to make
organic molecules (ex. glucose, food, etc.)
 Can capture energy from the sun (solar energy) or from chemosynthesis and
store it in the bonds of sugars, making it available to the rest of the community.
 Examples – plants, algae (protists), some bacteria
B. Consumers (Heterotrophs): Rely on other organisms for energy and nutrients by using
oxygen to break bonds in sugar and release its energy through cellular respiration
 Types of Consumers:
1. Herbivores: plant -eaters
2. Carnivores: meat-eaters
3. Omnivores: combination-eaters
4. Detritivores and decomposers: recycle nutrients within the ecosystem by
breaking down nonliving organic matter
C. Energy Flow
 When one organisms eats another, molecules are metabolized and energy is
transferred
 Trophic level: indicates the organism’s position in a sequence of energy transfers
 Producers always occupy the 1st trophic level of any community.
Food Chain
Food Web
linear series of feeding relationships
Sets of interrelated food chains
 In general, only about 10% of the energy available at any trophic level is passed to
the next; most of the rest is LOST to the environment as heat.
 List two food chains from the food web on the previous page:
1)
2)
 What would happen if all of the plants were removed?
 What would happen if all of the hawks were removed?
18-4 Ecosystem Recycling
Pages 371-374
As energy and matter flow through an ecosystem, matter must be recycled and reused.
These substances pass between the living and non-living worlds though biogeochemical
cycles.
A. Water Cycle:

Ground water - water found in soil or in
underground formations of porous rock

Transpiration - process by which water
evaporates from leaves of plants in
terrestrial ecosystems

Evaporation - adds water to the
atmosphere (liquid to gas)

Precipitation - the process by which
water leaves the atmosphere
B. Carbon Cycle:

Carbon is the building block of all living
things

Fossil fuels - Carbon-rich fuel from
ancient animals and plants

Photosynthesis - Energy (sun)+ Water +
Carbon dioxide Glucose + Oxygen

Cellular Respiration - Glucose+
Oxygen carbon dioxide + water +
Energy (ATP)

Decomposition - Breakdown of matter
by bacteria and fungi
C. Nitrogen Cycle:

Organisms need nitrogen to make
proteins and nucleic acids

Most plants can only use nitrogen in
the form of nitrate

Nitrogen fixation - process of
converting nitrogen gas into nitrate;
done by bacteria/lightning

Denitrification - bacteria break down
decaying organisms and release the
nitrogen they contain back into the
atmosphere
D. Phosphorous Cycle:

Phosphorous is a component of
DNA, RNA, and molecules that
store energy (ATP)

Phosphorous cycle is the
movement of phosphorous from
the environment to organisms, and
then back to the environment

Phosphorus is mainly found in
water, soil, rocks, and sediments
(no gas state)
Name
X BIO ECOLOGY STUDY GUIDE – CHAPTER 18
Date
Period
CHAPTER 18 – INTRODUCTION TO ECOLOGY
ecology
interdependence
biosphere
ecosystem
community
population
biotic factor
abiotic factor
1. You go on a field trip to a farm, using the terms from the word bank above, identify the
various units below:
a. The herd of cattle that live on the farm (2 answers): population/biotic
b. The amount of rainfall that the farm receives:
abiotic
c. The entire farm, including livestock and the soil, sunlight, etc.: ecosystem
d. The chickens, ducks, horses, cows, etc. (2 answers):
community/biotic
2. Distinguish between a habitat and a niche.
Habitat: physical area in which an organism lives
Niche: way of life of a species, includes its habitat, feeding habits, reproduction habits
3. According to the graph on pg. 367, which ecosystem has the greatest net primary
productivity?
Tropical rain forest
The least?
Open ocean & desert
4. How does a food chain differ from a food web?
Food chain: specific sequence in which organisms obtain energy
Food web: all of the interrelated food chains in an ecosystem
5. What would happen to the other organisms in the food web below if you removed the grass
(producer)?
They would not survive because there is no primary food source
6. What percentage of the total energy consumed in one trophic level is available to the
next? 10%
Why is this so low? because some avoid getting eaten, some molecules can’t be used, E used
by prey can’t be used by predators, no transformation is 100% efficient.
7. What five substances pass through biogeochemical cycles?
Water, carbon, oxygen, nitrogen, phosphorus
8. Label the diagram below with the following terms: evaporation(2X), transpiration,
precipitation (2x), runoff, movement of H2O vapor by wind:
Movement of H2O by wind
What is being cycled in the diagram?
Water
Preci
p
Evap
Transpiration
Precipitation
Evaporation
9. What are the two main processes of the carbon cycle?
Photosynthesis and respiration
How are these related? (remember way back to chapters 6 & 7)
products of one are the reactants of the other
10. What contributes to the increase in atmospheric carbon?
burning fossil fuels and other organic matter
11. How does atmospheric nitrogen get converted into a useable form?
Nitrogen Fixation
What organisms do this?
Nitrogen - Fixing bacteria and lightning
12. Why is phosphorus an important material to animals?
it is essential to animals so they can form bones, teeth, and molecules (DNA, RNA)
13. Where is phosphorus mainly found? in rocks
19-1 Understanding Populations
Pages 381-384
A. Population ecology: studies changes in population size and the factors that regulate
populations over time
B. Populations are affected by three things: size, density, and dispersion
1. Population size: number of individuals
2. Population density: the number of individuals of a species per unit area or
volume (Ex: number of earthworms per cubic meter of soil)
3. Population dispersion: how the population is spread out in a given area (Ex.
Clumps, uniform, or random)
19.2 Measuring Populations
Pages 385-389
A. Population Growth Rate

Determined by the following equation:
Growth rate = rate of individuals gained – rate of individuals lost
or
(birth rate + immigration rate) – (death rate + emigration rate)

Growing populations have a positive growth rate; shrinking populations have a
negative growth rate.
B. Exponential growth model: the rate of population
growth under ideal conditions

As the population size grows, more individuals
are added during each interval

Graphing this data gives a J-shape curve

Exponential growth can NOT continue
indefinitely

Eventually, one or more environmental
factors will limit growth

Ex: space and food supply
C. Logistic growth model: idealized population growth that is slowed by limiting factors
as the population size increases

Results in formation of an S-shape curve

Carrying capacity (K) - maximum
population size that a particular
environment can sustain

K varies depending on the species and
the resources available

Limiting Factors to growth = predators,
parasites, food sources, water & space

Emphasizes that resources are finite

At low populations, resources are
abundant and the population is able to
grow nearly exponentially

Population stabilizes at the carrying capacity when the birth rate equals the
death rate
Name
X BIO ECOLOGY STUDY GUIDE – CHAPTER 19
Date
Period
CHAPTER 19 – POPULATIONS
1.
According to the graph on the right, during which time
period (1, 2, 3, or 4) does:
a) the population show negative growth? ___4____
b) the population show positive growth? 1 (little) & 2 (most)
c) the population show no growth? __3__
2.
How is population growth rate determined?
By subtracting death rate from birth rate GR = BR - DR
3.
What four processes determines a population’s growth rate? Identify which two add
individuals and which two subtract individuals from the population.
Births (+) Deaths (-) Immigration (+) Emigration (-)
4.
Which of the following is true in the exponential model of population growth?
A) Population growth continues indefinitely.
B) Population growth stops at the carrying capacity.
C) Population growth increases and then decreases.
D) The immigration rate falls with increasing population size.
5.
On the diagram below, label the following: # of individuals, time, carrying capacity,
exponential growth, logistic growth.
# of individuals
A Exponential
Carrying capacity
Which line is more typical of
a population in nature? B
B Logistic
Why? Because it depicts the carrying capacity of the
ecosystem
Why is growth initially so slow?
Because the population is so
small and only a few females are
producing young
Time
20-1 Species Interactions
Pages 399-404
A. Communities contain interacting populations of many species
B. 3 major types – predation, competition, and symbiosis
1.
Predation - predator eats all or part of an
individual  the prey
Adaptations of predators: venom, flesh-

cutting teeth, sticky webs, speed
Adaptations of prey: camouflage, chemical

defenses (plants & animals), mimicry (resembles another species) ,
thorns, spines
2.
Competition - Limited resources force competition among living things in same
niche

All competition almost always produces a
winner and a loser (dies out)

Ex: two species of paramecium kept in
same culture…one species out competed
the other.
3.
Symbiosis = “together living”

Any relationship where 2 species live in close association with each other

3 main types of symbiotic relationships: mutualism, parasitism,
commensalism

Mutualism (“win-win”): both benefit

ex: sea anemone and clown fish. Clown
fish gets a protected home and the
anemone gets a defender when
attacked

Parasitism (“win-lose”): one benefits at the harm of the other (host)

ex: Tapeworm inside a human. Tapeworm absorbs digested
food of host, the host’s cells starved for nutrition.

Commensalism (“win-no harm/help”): one benefits while the other is
neither harmed nor helped

ex: Barnacles on a whale. Barnacles
benefit by motion of whale and the
movement of food particles over them. No benefit or harm
comes to the whale.
Directions: Complete the following graphic organizer.
Community Interactions
Interactions among organisms
that help to shape the
ecosystem in which they live
More than one
organism tries to
use a resource at
the same time, in
the same place
Predation
_______________
_______________
_______________
_______________
_________
One species
benefits, the
other is
harmed
Relationship in
which two
species live
close together
One species
benefits, the
other is
unaffected
Both species
benefit
Directions: Identify the interaction being described.
_______________________1. Today I am in the central part of Africa. I spent the day observing the warthog
and the oxpecker (a species of bird). The oxpecker was observed on the backs
of the warthogs, where it appears to be feeding on something. On closer
observation of the skin of a tranquilized warthog and later the stomach contents
of an oxpecker, it appears that the oxpecker is eating ticks from the skin of the
warthog.
_______________________2. Today I am in Tanzania, located in East Africa. I spent most of today observing
grazing cape buffalo. I noticed that cattle egrets (a species of bird) were
concentrated in those areas where cape buffalo were grazing. Upon closer
observation, it was seen that the cattle egrets were feeding on insects that were
flushed from the vegetation by the grazing cape buffalo.
_______________________3. Today I am in South America. I have been observing tomato hornworm
caterpillars for a few days now. A braconid wasp was observed paralyzing the
caterpillar. The wasp then deposited its eggs on the caterpillar.
_______________________4. Today I am in Yellowstone National Park to estimate the size of the gray wolf
population in the park. I saw four wolves successfully kill a deer. They swiftly
separated her from the small heard and attacked her from two different
directions. The rest of the deer herd ran away to safety. The wolves immediately
began eating the deer.
_______________________5. Today I am in Costa Rica. I spent the day observing a tree called the bull’s horn
acacia. A certain species of stinging ant appears to live in the hollow thorns of
these trees. The ants are observed feeding on sugar produced by nectarines on
the tree and also on the protein-rich swellings called Beltian bodies that grow at
the tips of leaflets. The ants are observed attacking anything that touches the
tree.
_______________________6. Today I am located off the coast of Southern Florida, where I have been scuba
diving for a few days in order to observe sharks. Remoras (a species of fish) are
observed travelling attached to a shark. They appear to feed on scraps of food
dropped by the shark as it eats. The shark does not seem to notice the presence
of the remoras.
_______________________7. Today I am scuba diving in the coastal area of Kenai Fjords National Park in
Alaska. I observed sea otters eating sea urchins. It was amazing to see the sea
otter pick up the spiny sea urchins in their paws and crush the shells with their
blunt teeth. The soft body was eaten and the spiny shell was quickly discarded.
_______________________8. Today I am located at my lab in upstate New York. I have been observing a fir
tree found in the forest behind my lab for a few weeks. The tree seems to be
dying and a species of mistletoe appears to be growing on the fir tree.
20-2 Patterns in Communities (Succession)
Pages 407-410
A. Succession: a
•
In 1833, volcanic island of Krakatau completely destroyed by an
eruption – left completely barren
•
2 years later, grasses are present
•
14 years later, 49 plant species and lizards, birds, insects, and bats
•
By 1929, a forest with 300 plant species were present
•
Today the island is a mature rainforest
•
HOW?
progressive, predictable ecological change in a community
over time
A. Primary Succession: Begins with no remnants of the previous community

Pioneer species are first to colonize barren land
–
Ex: lichen (fungus and algae) turn rock into soil, turn N2 gas into useful
nitrogen forms, and add organic material to the soil
B. Secondary Succession: occurs after a major event disturbs a community (fire, flood,
earthquake, hurricane, human activity like forest clearing or farming)

SOIL survives the disturbance, plants re-colonize the area faster than in primary
succession, herbivores can move in and make use of the food supply. Then,
carnivores can move in

If ecosystem is healthy, it
may be restored to its
natural state prior to
disturbance (the “climax”
community) BUT sometimes the impact is so traumatic, a full recovery through
succession is not possible
Name
X BIO ECOLOGY STUDY GUIDE – CHAPTER 19
Date
Period
CHAPTER 20 – COMMUNITY ECOLOGY
1. What is predation?
When individual of one species (predator) eats all or part of an individual of another (prey)
2. List four examples of adaptations that predators have evolved.
Acute sense of smell, venom, heat sensitive pits, sticky webs of spiders, teeth that cut flesh.
3. List four examples of adaptations that prey have evolved to avoid predators.
Deceptive markings, fleeing, hiding or resembling other objects, chemical defenses
4. What is a symbiosis?
Relationship in which 2 dissimilar organisms live together in a close association
5. List and explain the three types of symbiotic relationships.
a) Parasitism: 1 organism (the parasite) benefits (obtains nutrients) from the host (who is harmed)
b) Commensalism: one benefits, the other neither benefits nor is harmed
c) Mutualism: both benefit from living together
6. What is ecological succession?
The gradual, sequential replacement of populations in an area
7. Distinguish between primary and secondary succession.
Primary: the sequential replacement of populations in an area that has not previously
supported life (i.e. bare rocks, sand dunes)
Secondary: the sequential replacement of populations in disrupted habitats that have not
been totally stripped of soil and vegetation (i.e. and area that was flooded, destroyed by
fire, etc.)
8. Distinguish between pioneer species, seral community, and climax communities.
Pioneer species: the first species to colonize a new habitat
Seral community: the intermediate communities that arise
Climax community: final community, a community that will remain stable as long as the
area is undisturbed
21-1 Terrestrial Biomes
Pages 417-422
B. Biomes: large climatic regions that contain a number of smaller but related
ecosystems within them
– Characterized by similar plant and animal species
Biome
Temperature/Rainfall
Tropical Forest
25°C-27°C
200-400cm
Temperate Forest
6°C-28°C
75-125cm
Taiga
-10°C-14°C
35-75cm
Desert
24°C-34°C
<25cm
Temperate
Grassland
0°C-25°C
25-75cm
Savanna
16°C-34°C
75-150cm
Tundra
-26°C-4°C
<25cm
Predominant Plant
Species
Broadleaf evergreen
trees and shrubs
Broadleaf deciduous
trees and shrubs
Needle-leafed
evergreen trees
Succulent plants;
scattered grasses and
sagebrush
Dense tall grasses in
moist areas; short
clumped grasses in drier
areas
Predominant Animal
Species
Insects, colorful birds,
apes, monkeys,
predatory cats
White-tailed deer, foxes,
raccoons, squirrels,
black bears, birds (blue
jays, cardinals)
Moose, bears, lynx
Camel, ground squirrel,
jack rabbit
Bison, antelope,
elephants, giraffes,
kangaroos
Tall grasses and
scattered trees
Zebras, wildebeests,
giraffes, gazelles, lions,
leopards, cheetahs
Mosses, lichens, dwarf
woody plants
Duck, geese, predatory
birds, caribou
intertidal
neritic
(eu)photic zone - Where light
reaches so photosynthesis can
occur
aphotic zone – No light reaches
oceanic
photic
pelagic
aphotic
Name
X BIO ECOLOGY STUDY GUIDE – CHAPTER 21
Date
Period
CHAPTER 21 - ECOSYSTEMS
1.
What is a biome?
A large area identified by the presence of characteristic plants and animals
2.
Using the map on page 417, in which biome would each of the following places be?
3.
a) Central Australia:
Desert
b) Miami, Florida:
Temperate forest
c) Central America:
Tropical rain forest
d) Spain:
Grassland (Chaparral)
Using the terms in section 21-2 (start p. 423), match the correct zone for the following phrases:
a) Organisms have adapted to periodic exposure to air: intertidal zone
b) Where photosynthesis occurs: photic zone
c) Supports the greatest amount of marine life: neritic zone
d) Deep water of the open sea: pelagic zone
30. Using the same terms as above, label the diagram below:
intertidal
neritic
0m
200m
photic
pelagic
Continental Shelf
aphotic
2,500-6,000m
Humans rely on Earth’s life-support systems
BUT…
We affect our environment when we:
Obtain food
Eliminate waste products
Build places to live
22.1 Biodiversity
Pages 438-439
A. Biodiversity: total of all the genetically-based variation in all organisms in the
biosphere
•
1.8 million species already identified AND 30 million more estimated
yet to be discovered!!
Benefits of Biodiversity



Sources of medicines
Genetic diversity used to
increase pest resistance
Keystone species (if
removed) can change
entire ecosystem
Threats to Biodiversity





Altering habitats
Hunting
Introducing invasive
species
Releasing pollution
Contributing to climate
change
Conserving Biodiversity



Protect individual species
Preserve habitats and
ecosystems
Consider local interests
B. Invasive Species: species that are not found naturally in an area and have been
brought to the area by artificial means
C. Extinct Species: species that no longer have any living members left
a. Caused by disruption of ecosystems (ex. Habitat destruction by humans)
D. Endangered Species: species that are in danger of extinction
E. Keystone species: a change in one species can have drastic effects on many other
species in the community
KELP




SEA URCHINS
SEA OTTERS
Otters are a keystone species - they keep the sea urchin
population in check
Over hunting of the otters allowed urchin population to
explode, giant kelp forests destroyed by urchin activity
With no kelp, many animals were without a habitat
Otters are now protected species, urchin population is under
control and kelp forests have rebounded
22-2 Environmental Issues
Pages 440-444
A. The Effect of Human Activity
Activity
Definition
Positives
Negatives
Agriculture
Supplies a
Enabled human settlements
dependable that ultimately led to
food source modern civilization
that can be
stored for
later use
Impacts natural resources
as >7 billion people!!! need
(ex. Food, fresh water, fertile
soil, fossil fuels)
Development
Trend to
move to
suburbs &
cities
High standard of living
Produce lots of waste that
affect air, water, & soil
resources
Uses up farmland
Divides natural habitats into
fragments
Industrial
Industry &
scientific
know-how
Modern conveniences of life
such as comfortable homes,
clothes, electronic devices
Require energy and
consume power
Need to burn fossil fuels
(coal, oil, & natural gas)
Wastes discarded into air,
water, & soil
Growth
B. Sustainable Development
•
Renewable vs. Nonrenewable Resources
–
Renewable – can be renewed or replaced by a healthy ecosystem
•
–
Ex. a single southern white pine
Nonrenewable – natural processes cannot replenish them in a reasonable
amount of time
•
Ex. Fossil fuels (formed from buried organic material over millions of
years), a whole forest of white pines
•
•
Sustainable Resource Use
•
Provides for human needs & wants AND
•
Preserves the ecosystems that produce natural resources
Ecological Footprint – total area of functioning land and water ecosystems needed
both to provide the resources an individual or population uses and to make
harmless the wastes that an individual or population generates
•
•
•
•
•
•
•
The average American has an ecological footprint that is:
–
4x larger than global average
–
2x that of England
–
6x that of China
C. Using Resources Wisely: Soil
•
•
Why is it needed?
–
When healthy, supports agriculture and forestry
–
Topsoil – absorbs/retains moisture but allows water to drain
What are we doing to destroy it?
–
Allowing soil erosion – nutrients are washed away with rain
•
Desertification – over-plowing, overgrazing, allowing land to be barren
between plantings
•
Deforestation – loss of forests
–
•
Forests help to hold soil in place, absorb CO2, absorb freshwater
How can we protect it?
•
Leaving stems and roots in place between plantings
•
Crop-rotation
•
Contour Plowing and Terracing –
creating steps to prevent water
and soil from flowing downward
•
Creating tree farms (makes trees
a renewable resource)
D. Using Resources Wisely: Freshwater
•
Why is it needed?
–
Drinking water, industry, transportation, energy,
waste disposal
•
What are we doing to destroy it?
–
Overuse (Ogallala aquifer – took 1 million years
to collect)
–
Pollution
•
Factories, oil spills, industrial/agricultural
chemicals
–
Biomagnification – pollutants (like
DDT, PCBs, heavy metals) magnify as they move through the
food chain from primary producers to primary consumers, etc.
•
•
Residential Sewage
How can we protect it?
–
Protection of natural resources
involved in water cycle (ex. Plants can
filter out pollutants)
–
Watershed conservation – protecting
all inter-connected bodies of water
•
Watershed – an area of land
that drains to a common location
–
Pollution control
•
Sewage treatment, decrease pesticide use (use biological controls
instead of poisonous sprays)
–
Water conservation (ex. drip irrigation)
E. Using Resources Wisely: Atmospheric
•
Why is it needed?
–
•
Oxygen, absorption of UV radiation, regulation of global temperature
What are we doing to destroy it?
–
Pollution (Industry, Burning Fossil Fuels)
•
Smog - Ground Level Ozone
–
•
Acid Rain – nitrogen and sulfur oxides mixing with precipitation
–
•
Causes respiratory diseases
Damages plants, releases toxic elements from soil
Greenhouse Gases – burning of fossil fuels releases CO2, CH4 and H2O
–
Releases carbon dioxide into the air, contributes to global
warming and climate change
•
Particulates – microscopic particles of ash and dust released by
industry
–
•
Can be inhaled and cause respiratory problems
How can we protect it?
–
Emission standards
–
Clean-air regulations
–
Unleaded gasoline
F. Using Resources Wisely: Ozone
•
Why is it needed?
–
•
Layer
Ozone Layer – molecules of O3
What are we doing to destroy it?
–
Primary problem is CFCs (Chloroflurocarbons)
•
Found in refrigerants, aerosol cans and
plastic foams
•
How can we protect it?
–
CFCs banned in the late 80’s (Montreal Protocol),
however residual CFCs can remain in the
atmosphere for more than 30 years!!
G. Using Resources Wisely:
•
Fisheries
What is the problem?
–
Despite increased efforts and new
technology, seafood catch numbers
continue to decline
•
What are we doing to destroy it?
–
Overfishing: Death rates (commercial fishing) surpassed the birth rates of the
fish
•
How can we protect it?
–
Regulations put in place to limit fish catches
–
Certain areas closed to fishing until populations
recovered (Sustainable Fisheries Act)
–
Aquaculture – farming of aquatic animals
H. Using Resources Wisely:
•
Climate Change
What’s the Problem?
–
Global warming – increase in average
temperature of our planet (0.74ºC
between 1906 and 2005) with 11 of the 12
warmest years occurring between 19952006
•
–
Melting sea ice
–
Rising seal levels
What are we doing to destroy it?
–
Enhanced Greenhouse Effect not allowing
solar heat to move back into outer space
•
Burning fossil fuels, automobile
exhaust industrial pollution
•
How can we protect it?
–
Alternative energy sources (water, wind,
solar)
–
Decrease our ecological footprint
Name KEY
XBIO: Chapter 22 Study Guide
Date
Period
The Effect of Human Activity
1. What three human activities have transformed the biosphere?
agriculture, development, and industrial growth
Sustainable Development
2. Complete the Venn diagram to compare renewable and nonrenewable resources.
replaceable;
ex. fresh water,
clean air, wood, etc.
will be used up;
ex. fossil fuels,
minerals, etc.
Raw materials for
building,
manufacturing,
fuels, and food
Renewable Resources
Nonrenewable Resources
3. How can development be sustainable?
Development that is sustainable preserves ecosystems that provide renewable
resources, while it also provides for human needs.
4. The human population (currently around 7 billion) may reach 9 billion by 2100. Most of those people
will live in cities. Predict the impact of city growth on natural ecosystems and farmland. What will
happen if sustainable development is not achieved?
Increasing amounts of land will be needed to produce enough food. And increasing
amounts of resources will be needed to transport goods to cities. Without sustainable
development, air and water pollution will increase.
The Value of Biodiversity
5. What is biodiversity?
Total of all the genetically based variation in all organisms in the biosphere.
6. Why is biodiversity one of Earth’s greatest natural resources?
Species of many kinds provide us with foods, industrial products, and medicines.
Diverse species play vital roles in the delivery of ecological goods and services.
7. Explain why populations with the largest ecological footprints change the biosphere the most.
They use the most resources (land and water) to meet their needs and more resources
(land and water) are required to process their wastes. Land and freshwater resources
are easy to pollute but difficult to clean up. Other organisms also need these
resources, which broadens the effect on the biosphere.