Environmental Science and Sustainability
What is Environmental Science?
• Environmental Science is the study of
the air, water, and land surrounding an
organism or a community, which ranges
from a small area to Earth’s entire
biosphere.
• It includes the study of the impact of
humans on the environment.
The Earth
• Life has existed on earth for 3.8 billion
years
• Earth is well suited for life
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Water covers over 71% of the planet
Habitable temperatures
Moderate sunlight
Atmosphere provides oxygen and carbon
dioxide
– Soil provides essential minerals for plants
• However, each day humans are altering
the planet.
Human Impact through History
• Hunter-gathers- caused some animals to become
extinct, including:
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giant sloths
giant bison
mastodons
cave bears
saber-toothed cats
• Agricultural revolution-caused human population to
grow and destroyed land.
• Industrial revolution- shift to fossil fuels. Improved
quality of life for people but allowed for urban areas
to flourish.
Industrial Revolution
• The Industrial Revolution introduced many
positive changes. However, it also introduced
many new environmental problems, such as
pollution and habitat loss.
• In the 1900s, modern societies began to use
artificial substances in place of raw animal
and plant products.
• As a result, we know have materials such as
plastics, artificial pesticides, and fertilizers.
Earth As a System
• System
– A set of components that interact and
function as a whole
• Global Earth Systems
– Climate, atmosphere, land, coastal zones,
ocean
• Ecosystem
– A natural system consisting of a community
of organisms and its physical environment
• System approach to environmental science
– Helps us understand how human activities
effect global environmental parameters
The Earth -Closed System
• We produce wastes (pollution) that we
can not get rid of.
• We have local and global environmental
issues.
• Limited resources
• Population increase causes a strain on
resources
Population Growth
• In the past 50 years, nations have used
vast amounts of resources to meet the
worlds need for food.
• Producing enough food for large
populations has environmental
consequences such as habitat
destruction and pesticide pollution.
Carrying Capacity
• Carrying capacity is the largest population
that can be maintained for an indefinite
period by a particular environment that is not
undergoing change
Human Population Growth
The world population reached 7 billion in 2012
– Growing exponentially
Population
• Globally, 1 in 4
people lives in
extreme poverty
– Without basic food,
clothing, and shelter
• Difficult to meet
population needs
without utilizing
earth’s resources
Gap Between Rich and Poor
• In highly developed countries (U.S., Canada,
France, Germany, Japan…):
– Low birth rate, low infant mortality, low fertility
rate, long life expectancies, and goods and services
a citizen can buy
• In developing countries
– High birth rate, high infant mortality, high
fertility rate, short life expectancies, and low
goods and services a citizen can buy
Overpopulation
• People overpopulation
– Too many people in a given geographic area
– Problem in many developing nations
• Consumption overpopulation
– Each individual in a population consumes too
large a share of the resources
– Problem in many highly developed nations
What are our main
Environmental Problems?
1. Resource depletion- Using our resources up
faster that they can be replaced.
a. Renewable resource- resources that can be
replaced relatively quickly
ex. Trees, water, soil, air and crops
b. Nonrenewable resource- can not be replaced
quickly
Ex. Fossil fuels, minerals, and metals
»Easter Island
Tragedy of the
Commons
• Garrett Hardin (1915-2003)
• Solving Environmental Problems is result
of struggle between:
– Short term welfare
– Long term environmental stability and
societal welfare
• Garrett used Common Pastureland in
medieval Europe to illustrate the
struggle
Tragedy of the Commons
Tragedy of the Commons
• The commons were eventually replaced by
closed fields owned by individuals.
• Owners were now careful not to but too many
animals on their land, because overgrazing
wouldn’t allow them to raise as many animals
next year.
• Hardin’s point being that someone or some
group must take responsibility for maintaining
a resource or it will become depleted.
What’s your Ecological Footprint?
Ecological Footprint
The average amount of land, water and ocean
required to provide that person with all the
resources they consume
What are our main
Environmental Problems?
2.Pollution- undesired change in air, water or
soil that has adverse affects.
a. biodegradable pollutants- can be broken
down by natural processes.
ex. Human sewage and paper
b. nonbiodegradable pollutants- can not be
broken down by nature.
ex. Mercury, lead, and some types of
plastic
E-Waste
What are our main
Environmental Problems?
3. Loss of biodiversityrefers to the number
and variety of species
that live in an area.
Endangered species-A
species that is in danger
of becoming extinct
Threatened species-a
species that numbers
are falling rapidly
Environmental Sustainability
• The ability to meet current human need
for natural resources without
compromising the needs of future
generations
• Requires understanding:
– The effects of our actions on the earth
– That earth’s resources are not infinite