Transcript Presentation

MILLER/SPOOLMAN
LIVING IN THE ENVIRONMENT
17TH
CHAPTER 1
Environmental Problems,
Their Causes, and
Sustainability
Environmental Science Is a Study of
Connections in Nature
• Environment: Everything around us
• Sustainability: the capacity of the earth’s natural
systems and human cultural systems to survive,
flourish, and adapt into the very long-term future
• Environmental science: interdisciplinary science
connecting information and ideas from
• Natural sciences: ecology, biology, geology,
chemistry…
• Social sciences: geography, politics, economics
• Humanities: ethics, philosophy
Nature’s Survival Strategies Follow
Three Principles of Sustainability
1. Reliance on solar energy
•
The sun provides warmth and fuels photosynthesis
2. Biodiversity
•
Astounding variety and adaptability of natural
systems and species
3. Chemical cycling
•
•
Circulation of chemicals from the environment to
organisms and then back to the environment
Also called nutrient cycling
Solar
energy
Natural Capital
Natural Capital = Natural Resources + Natural Services
Air
Renewable
energy (sun,
wind, water
flows)
Air purification
Climate control
UV protection
(ozone layer)
Life
(biodiversity)
Population
control
Water
Water purification
Pest
control
Waste treatment
Soil
Nonrenewable
minerals
(iron, sand)
Soil renewal
Land
Food production
Nutrient
recycling
Nonrenewable
energy
(fossil fuels)
Natural resources
Natural services
Fig. 1-4, p. 9
We Are Living Unsustainably
• Environmental degradation: wasting, depleting, and
degrading the earth’s natural capital
• Happening at an accelerating rate
• Also called natural capital degradation
Natural Capital Degradation
Degradation of Normally Renewable Natural Resources
Climate
change
Shrinking
forests
Decreased
wildlife
habitats
Air pollution
Soil erosion
Species
extinction
Water
pollution
Aquifer
depletion
Declining
ocean fisheries
Fig. 1-9, p. 13
Some Sources Are Renewable and
Some Are Not
• Resource
• Anything we obtain from the environment to meet
our needs
• Renewable resource
• Several days to several hundred years to renew
• E.g., forests, grasslands, fresh air, fertile soil
• Nonrenewable resources
• does not renew itself at a sufficient rate for
sustainable economic extraction
• Energy resources
• Metallic and nonmetallic mineral resources
Some Sources Are Renewable and
Some Are Not
• Sustainable yield
• Highest rate at which we can use a renewable
resource without reducing available supply
• Perpetual resource
• Solar energy
• Reuse and Recycle
• Possible 80-90% of currently used resources
Countries Differ in Levels of
Unsustainability
• Economic growth: increase in output of a nation’s
goods and services
• Gross domestic product (GDP): annual market value
of all goods and services produced by all businesses,
foreign and domestic, operating within a country
• Per capita GDP: one measure of economic
development
Pollution Comes from a Number of
Sources
• Sources of pollution
• Point sources
• E.g., smokestack
• Nonpoint sources
• E.g., pesticides blown into the air
• Main type of pollutants
• Biodegradable - a pollutant which can be detoxified in some
manner in the environment
• Nondegradable – not subject to or capable of degradation.
Ecological Footprints: A Model of
Unsustainable Use of Resources
• As our ecological footprints grow, we are depleting
and degrading more of the earth’s natural capital.
• In 2003, the US per capita ecological footprint
was about 4.5 times the average global footprint
per person and 6 times larger than China’s per
capita footprint
• In 2008, the global ecological footprint was at
least 30% higher than the earth’s biological
capacity and is projected to be twice the planet’s
biological capacity by around 2035.
Cultural Changes Have Increased Our
Ecological Footprints
• If per capita usage of renewable resources continues
at the current rate, we will need 2 planet Earth’s
• If per capita usage equals that of the US, we will
need 5 planet Earth’s.
• Three major cultural events
• Agricultural revolution
• Industrial-medical revolution
• Information-globalization revolution
• Current need for a sustainability revolution
Major Causes of Environmental Problems
Fig. 1-17, p. 20
Harmful Effects of Poverty
Fig. 1-20, p. 22
MILLER/SPOOLMAN
LIVING IN THE ENVIRONMENT
17TH
CHAPTER 2
Science, Matter, Energy,
and Systems
Core Case Study: A Story About a
Forest
• 1963 river valley experiment in New Hampshire
• Compared the loss of water and nutrients from an uncut
forest (control site) with one that had been stripped
(experimental site)
• 3 years of collecting data showed the stripped site had:
• 30-40% more runoff
• More dissolved nutrients being carried away with the runoff
• More soil erosion
The Effects of Deforestation on the Loss
of Water and Soil Nutrients
Fig. 2-1, p. 31
Science Is a Search for Order
in Nature
• Scientific Method – a series of steps to learn how the
physical world works.
• Scientific Theory – a widely accepted hypothesis
supported by observations and measurements.
• Scientific Law – a tested and accepted description of
what happens repeatedly in nature.
The Scientific Process
Fig. 2-2, p. 33
Matter Consists of Elements and
Compounds
• Matter
• Has mass and takes up space
• Elements
• Unique properties
• Cannot be broken down chemically into other substances
• Compounds
• Two or more different elements bonded together in fixed
proportions
• Molecule
• Two or more atoms of the same or different elements held
together by chemical bonds
Atoms, Ions, and Molecules Are the
Building Blocks of Matter (1)
• Atomic theory
• All elements are made of atoms
• Subatomic particles
• Protons with positive charge and neutrons with no charge in
nucleus
• Negatively charged electrons orbit the nucleus
• Atomic number
• Number of protons in nucleus
• Mass number
• Number of protons plus neutrons in nucleus
Organic Compounds Are the
Chemicals of Life
• Organic compounds
• Contain at least 2 carbon atoms combined with atoms of one or
more other elements
• Simple carbohydrates (sugars)
• Macromolecules: complex organic molecules
•
•
•
•
Complex carbohydrates
Proteins
Nucleic acids
Lipids
• Inorganic compounds
• All other compounds (with the exception of Methane CH₄)
Matter Comes to Life through Genes,
Chromosomes, and Cells
• Cells: fundamental units of life; all organisms are
composed of one or more cells
• High-quality matter
• Highly concentrated
• Near earth’s surface
• High potential as a resource
• Low-quality matter
• Not highly concentrated
• Deep underground or widely dispersed
• Low potential as a resource
Matter Undergoes Physical and
Chemical
• Physical change
• No change in chemical composition
• Chemical change, chemical reaction
• Change in chemical composition
• Reactants and products
• Law of conservation of matter
• Whenever matter undergoes a physical or chemical
change, no atoms are created or destroyed
Energy Comes in Many Forms (1)
• Kinetic energy
• Flowing water
• Wind
• Heat
• Transferred by radiation, conduction, or convection
• Potential energy
• Stored energy
• Can be changed into kinetic energy
• Sun provides 99% of earth’s energy
• Warms earth to comfortable temperature
• Plant photosynthesis
• Winds
Energy Changes Are Governed by Two
Scientific Laws
• First Law of Thermodynamics
• Law of conservation of energy
• Energy is neither created nor destroyed in physical
and chemical changes
• Second Law of Thermodynamics
• Energy always goes from a more useful to a less useful
form when it changes from one form to another
Time Delays Can Allow a System to
Reach a Tipping Point
• Time delays vary
• Between the input of a feedback stimulus and the
response to it
• Tipping point, threshold level
• Causes a shift in the behavior of a system
• Melting of polar ice
• Population growth
MILLER/SPOOLMAN
LIVING IN THE ENVIRONMENT
17TH
CHAPTER 3
Ecosystems: What Are They
and How Do They Work?
Core Case Study: Tropical Rain Forests
Are Disappearing
• Cover about 2% of the earth’s land surface
• Contain about 50% of the world’s known plant and
animal species
• Disruption will have three major harmful effects
• Reduce biodiversity
• Accelerate global warming
• Change regional weather patterns
The Earth’s Life-Support System Has
Four Major Components
• Atmosphere
• Troposphere: where weather happens
• Stratosphere: contains ozone layer which filters 95%
of UV radiation
• Hydrosphere
• Contains all water on and near Earth
• Biosphere
• Where all life is found
Ecologists Study Interactions in Nature
• Ecology: how organisms interact with each other and
their nonliving environment
• Organisms: different species interacting with one
another
• Biotic – living like plants, animals, microbes; Abiotic –
nonliving like water, air , rocks
• Populations: Groups of the same species living in a
particular place
• Communities: Populations living in a particular place,
potentially interacting with one another
Producers and Consumers Are the Living
Components of Ecosystems (1)
• Producers, autotrophs – self-feeders
• Photosynthesis:
• CO2 + H2O + sunlight → glucose + oxygen
• Consumers, heterotrophs
• Primary consumers = herbivores
• Secondary consumers = carnivores that eat
herbivores
• Tertiary consumers = carnivores that eat carnivores
• Omnivores = eat plants and animals
Producers and Consumers Are the Living
Components of Ecosystems (2)
• Decomposers
• Consumers that release nutrients
• Bacteria
• Fungi
• Detritivores
• Feed on waste and dead bodies of other organisms
• Earthworms
• Vultures
Producers and Consumers Are the Living
Components of Ecosystems (3)
• Aerobic respiration
• Using oxygen to turn glucose back to carbon dioxide
and water
• Anaerobic respiration = fermentation
• End products are carbon compounds such as methane
or acetic acid
Science Focus: Many of the World’s Most
Important Species Are Invisible to Us
Microorganisms
• Bacteria – helps purify water
• Protozoa – helps provide planet’s oxygen
• Fungi – decomposer
Energy Flows Through Ecosystems in
Food Chains and Food Webs
• Food chain
• Movement of energy and nutrients from one trophic
level to the next
• Food web
• Network of interconnected food chains
Usable Energy Decreases with Each
Link in a Food Chain or Web
• Biomass
• Organic matter in a food chain or food web
• Decreases at each higher trophic level due to heat loss
• Pyramid of energy flow
• 90% of energy lost with each transfer
• Less chemical energy for higher trophic levels
Some Ecosystems Produce Plant
Matter Faster Than Others Do
• Gross primary productivity (GPP)
• Rate at which an ecosystem’s producers convert solar
energy to chemical energy and biomass
• Kcal/m2/year
• Net primary productivity (NPP)
• Rate at which an ecosystem’s producers convert solar
energy to chemical energy, minus the rate at which
producers use energy for aerobic respiration
• Ecosystems and life zones differ in their NPP
Estimated Annual Average NPP in Major Life Zones
and Ecosystems
Fig. 3-15, p. 66
Nutrients Cycle in the Biosphere
• Biogeochemical cycles, nutrient cycles
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•
•
•
•
Hydrologic
Carbon
Nitrogen
Phosphorus
Sulfur
• Nutrients may remain in a reservoir for a period of
time
Water Cycles through the Biosphere
• Natural renewal of water quality: major processes
•
•
•
•
Evaporation
Precipitation
Transpiration
Condensation
• Alteration of the hydrologic cycle by humans
• Withdrawal of large amounts of freshwater at rates faster than
nature can replace it
• Clearing vegetation causing increased runoff
• Increased flooding when wetlands are drained
• Special properties of water
• Solvent, stays liquid, filters UV rays, expands as it freezes, holds
lots of heat
Carbon Cycle Depends on
Photosynthesis and Respiration
• Link between photosynthesis in producers and
respiration in producers, consumers, and
decomposers
• Additional CO2 added to the atmosphere
• Tree clearing
• Burning of fossil fuels
• Warms the atmosphere
Carbon dioxide
in atmosphere
Respiration
Photosynthesis
Animals
(consumers)
Diffusion
Burning
fossil
fuels
Forest fires
Plants
(producers)
Deforestation
Transportation
Respiration
Carbon in
plants
(producers)
Carbon dioxide
dissolved in ocean
Carbon in
animals
(consumers)
Decomposition
Marine food webs
Producers, consumers,
decomposers
Carbon in
limestone or
dolomite
sediments
Carbon in
fossil fuels
Compaction
Process
Reservoir
Pathway affected by humans
Natural pathway
Fig. 3-19, p. 70
Nitrogen Cycles through the
Biosphere: Bacteria in Action (1)
• Nitrogen fixed by lightning
• Nitrogen fixed by bacteria and cyanobacteria
• Combine gaseous nitrogen with hydrogen to make
ammonia (NH3) and ammonium ions (NH4+)
• Nitrification
• Soil bacteria change ammonia and ammonium ions to
nitrate ions (NO3-)
• Denitrification
• Nitrate ions back to nitrogen gas
Nitrogen Cycles through the
Biosphere: Bacteria in Action (2)
• Human intervention in the nitrogen cycle
1. Additional NO and N2O in atmosphere from burning
fossil fuels; also causes acid rain
2. N2O to atmosphere from bacteria acting on
fertilizers and manure
3. Destruction of forest, grasslands, and wetlands
4. Add excess nitrates to bodies of water
5. Remove nitrogen from topsoil
Nitrogen Cycle in a Terrestrial Ecosystem with Major
Harmful Human Impacts
Fig. 3-20, p. 71
Phosphorus Cycles through the
Biosphere
• Cycles through water, the earth’s crust, and living
organisms
• Limiting factor for plant growth
• Impact of human activities
1. Clearing forests
2. Removing large amounts of phosphate from the
earth to make fertilizers
3. Erosion leaches phosphates into streams
Impacts
Fig. 3-21, p. 73
Sulfur Cycles through the Biosphere
• Sulfur found in organisms, ocean sediments, soil, rocks, and
fossil fuels
• SO2 in the atmosphere
• H2SO4 and SO4• Human activities affect the sulfur cycle
• Burn sulfur-containing coal and oil
• Refine sulfur-containing petroleum
• Convert sulfur-containing metallic mineral ores
Natural Capital: Sulfur Cycle with Major Harmful
Impacts of Human Activities
Fig. 3-22, p. 74
Unit 1 Test Review
• Terms: Natural capital (examples), renewable and
nonrenewable resources (examples), GDP,
sustainable yield, ecological footprint, matter,
element, energy types, first law of thermodynamics
• Scientists estimate we can recycle and reuse what %
of resources we use now?
• More-developed countries have what% of the
population and use what% of all resources?
• Human activities have degraded what% of natural
resources?
• How many earth’s would we need if everyone in the
world consumed like the US?
Unit 1 test review
• Ecological footprint of a US citizen vs. China.
• 3 major cultural revolutions.
• Examples of pollution and effects. Point vs. nonpoint
pollution.
• % needed to bring about social change.
• Scientific method and steps. Law vs. theory.
• Policy life 4 stages, environmental lawsuits, SLAPP
• Public lands in the US
• Diane Wilson story
• Sustainibility and lobbyists (essays)