Transcript here

Environmental
problems, their
causes, and
sustainability
 Chapter 1
Objectives
 Recognize/explain that common resources need
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to be shared by all and resources need to be
conserved.
Examine population and growth patterns.
Identify the key environmental problems and
their causes.
Identify the difference between renewable,
nonrenewable and perpetual resources and
explain implications for continued use of each.
Explain the difference between point and
nonpoint pollution and provide examples of
each.
Living More
Sustainably
Living More Sustainably
 Keeping Terminology Straight
 Know the difference between:
 Environment – everything that affects a living organism
 Ecology – studies relationships between living organisms
and their environment
 Environmental science – collaboration of physical and
social sciences to learn how the earth works, how we
interact with the earth, & how to deal with
environmental problems
 Environmentalism – collaborative social movement
dedicated to protecting the earth’s life support systems
for us & other species
What keeps us alive?
 Our lifestyle and economies depend on
sun
(solar capital) & earth (natural capital)
 Capital – wealth used to sustain a business and
generate more wealth
 Example:
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You invest $100,000 of your money (capital).
You will receive a 10% return on that capital.
This equals $10,000
You now have a total of $110,000
You used your own money to generate more
money
What keeps us alive?
 We use solar capital to keep us alive
 Solar capital – energy from the sun that
we use to generate other types of
energy
 Two types:
 Direct sunlight
 Indirect sunlight
 Wind power
 Hydropower (energy from flowing water)
 Biomass (solar energy converted to chemical
energy that is stored; Example: wood)
What keeps us alive?
 We also use natural capital to keep us alive
 Natural capital – goods and services from the
natural environment which help sustain life
 Consists of:
 Natural resources
 Examples: Air, water, soil, wildlife, forest, fishery,
minerals
 Ecological Services
 Examples: Population control, nutrient recycling,
pollution control
 Biological income – Renewable supplies that can
renew & sustain people as long as we don’t
deplete them
 Examples: Wood, grassland, underground water
What is an environmentally
sustainable society?
 Preserves natural capital and lives off its
income
 In other words, it will meet basic resource needs of
its people indefinitely
 Does not deplete or degrade natural capital
 Does not compromise future generations
 Example: If you win $1 million in the lottery. If you choose to
spend the money, it will be gone in a matter of years. If you
choose to invest the money, you can live off the interest
WITHOUT touching the $1 million.
 **Protect the capital and live off the income it provides.**
(to ensure a sustainable environment)
Population growth,
economic growth,
economic
development and
globalization
Population growth
 The world’s population growth rate has slowed a
bit, but is still increasing pretty rapidly
 Exponentially at 1.25 % per year
 Example: In the year 2004…
 World’s population was 6.4 billion
 Increase of 80 million people
 219,000 people per day
 9,100 people per hour!
Economic growth vs. development
 Economic growth- An increase in the capacity of
a country to provide people with goods and
services
 Requires population growth
 Requires more production and/or consumption per person
 Measured by the % change in GDP
 Gross Domestic Product (GDP) - Annual market value
of all goods & services produced by all firms &
organizations, foreign & domestic, operating within a
country
 Changes in a country’s standard of living is called per
capita GDP
 Per capita GDP = GDP/total population at midyear
Economic growth vs. development
 Economic development – improvement of
living standards by economic growth
 Countries are classified by the United Nations
as being either:
 Developed country
 Developing country
Economic growth vs. development
Developed vs. Developing Countries
Developed Country
Developing Country
Examples
U.S., Canada, Japan,
Australia, New Zealand,
countries of Europe
Asia, Africa, South
America
Degree of
industrialization
High
Low
Per Capita GDP
High
Low
Contributing to world’s
population
1.2 billion
5.2 billion
Population growth
Slower
Faster
Economic development
Pros & Cons to Economic Development
Pros
Cons
Life expectancy doubled since 1950
Life expectancy 11 yrs less in developing
countries (when compared to
developed countries)
Infant mortality cut in half since 1955
Infant mortality rate in developing
countries 8+ times higher (when
compared to developed countries)
Food production ahead of population
growth since 1978
Harmful environmental effects of
agriculture may limit future food
production
Air and water pollution down in most
developed countries since 1970
Air & water pollution levels in most
developing countries too high
Number of people living in poverty has
dropped 6% since 1990
Half of the world’s people are trying to
live on less than $3 / day
Globalization
 Globalization - the process of social, economic, and
environmental global changes that lead to an
increasingly interconnected world
 Everyone is becoming interconnected through
exchanges of:
 People
 Products
 Services
 Capital
 Ideas
 Rate of globalization is influenced by:
 International trade / investments
 Human mobility
 Information / communication technologies
Resources
Resources
 Resource – anything obtained from the
environment to meet our needs and wants
 Examples: food, water, shelter, manufactured news,
transportation, communication, and recreation
 Resources are either:
 Direct resources - resources immediately ready for use
 Ex: water, air, solar energy
 Indirect resources– resources not directly available
 Ex: Petroleum; need to extract / refine petroleum to make
gasoline, heating oil, etc.
Resources
 Types of resources:
 1) Perpetual – renewed constantly
 Ex: solar energy
 Expected to last at least 6 billion yrs
 2) Renewable – can be replenished fairly rapidly (from
hours to decades) through natural processes
 Only works IF resources is not used up faster than its replaced
 Ex: forests, grasslands, fertile soil
 3) Nonrenewable – exist in a fixed quantity in the
earth’s crust
 Can be renewed but it takes a LONG time (millions to billions
of yrs)
 Are depleted faster than they are formed
 Include:
 Energy resources (Ex. Coal, oil, natural gas)
 Metallic mineral resources (Ex. Iron, copper, aluminum)
 Nonmetallic resources (Ex. Salt, clay, sand, phosphates)
Resources
 What do we do?
 1) Try to find more resources
 2) Recycle / reuse existing supplies
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(Except for nonrenewable energy—cannot be recycle)
 3) Waste less
 4) Use less
 5) Try to develop a substitute (for the resources)
 6) Wait millions of years for more to be produced
 Recycling – collecting waste materials, processing
them into new materials, and selling them
 Reuse – using resources again & again in the same
form (Ex. Glass bottles)
Resources
 Sustainable yield – the highest rate at which we can use
a resources indefinitely without reducing its available
supply
 Environmental degradation – exceeding a renewable
resource’s natural replacement rate
 Available supply begins to shrink
 Ex: urbanization of productive land, excessive topsoil erosion,
pollution, overgrazing, reduction of biodiversity
 Caused by common-property or free-access resources
 Nobody owns these resources
 Available to users at little / no charge
 Ex: air, open ocean & fish, wildlife, publicly owned land
(national parks)
Resources
 Tragedy of the Commons –
Garrett Hardin (1968)
 Overuse of common-property or free
access resources
 “If I do not use this resource, someone
else will. The little bit I use or pollute is
not enough to matter, and such
resources are renewable.”
 Works IF there are only a few users
 When many people use the resources,
they will exhaust or ruin it
 No one benefits = TRAGEDY
Resources
 Solutions:
 1) Use the free-access resources at or below their
sustainable yield
 Regulate access to it
 Reduce the population
 BOTH
 2) Convert free-access resources into private
ownership
 Not practical for global common resources
 Ex: Atmosphere, open ocean, most wildlife species
Ecological footprint (ECF)
 Measures how much of the earth’s natural capital &
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biological income each person uses
Our ECF exceeds the earth’s biological capacity to
replenish resources & absorb waste by 15%
USA – ECF is double what the country’s resources can
handle
Per person, ECF exceeds what the earth can replenish
naturally (by 15%)
If the ECF continues to increase, earth will NOT be able
to sustain life indefinitely