Environmental Science
Name: ______________________________
Chapter 1: Science and the Environment
Goal: The student will distinguish between renewable and nonrenewable resources and then classify
environmental problems into three major categories.
Vocabulary:
1. Natural resource
2. Pollution
3. Biodiversity
Chapter 1.3: Understanding Our Environment
Spaceship Earth
Earth has been compared to a ship traveling through space that cannot dispose of waste or take on new supplies
as it travels. Earth is essentially a ‘closed system.’ The only thing entering is energy from the sun and the only
thing leaving is heat. There are problems associated with this system. Some resources are limited. As
populations increase, those resources will be used up. Waste is also produced more quickly than we can dispose
of it.
Environmental problems can exist on different levels: local (where to build a landfill or arguing about the
importance of a rare bird or insect), regional (drinking water that may be affected by a polluted river) or global
(ozone-depleting chemicals released in one part of the world will impact all people in the world).
Population Growth: A Local Pressure
Environmental problems have been associated with the agricultural revolution and the Industrial Revolution as a
result of the rapid growth of the human population. The development of modern medicine and sanitation also
helped the increase in the human population (quadrupled during the 20th century). Producing enough food for
such a large population has environmental consequences (habitat destruction, pesticide pollution). Scientists
predict that the human population will continue to increase, doubling in the 21st century, before it begins to
stabilize.
What are Our Main Environmental Problems
There are unlimited numbers of environmental problems facing us today; however, almost all environmental
problems fall into one of three categories: resource depletion, pollution and loss of biodiversity.
Resource Depletion
A resource is depleted when a large part of it has been used up.
Natural resource – any natural substance that living things use (sunlight, air, water, soil, minerals, plants,
animals, forests, fossil fuels)
Natural resources can be classified as renewable and nonrenewable.
Renewable resources are resources that are continually replaced (solar, trees, fish, wind, air, water, soil, crops);
but can be depleted if used up faster than it can be replaced, ex: trees. Nonrenewable resources are resources
that form at a much slower rate and cannot be replaced (fossil fuels like oil, natural gas); when they are used up,
they are gone.
Resources are said to be depleted when a large fraction of the resource has been used up (ex: trees that are
harvested faster than they can grow naturally in an area)
Pollution
The Industrial Revolution began producing wastes faster than the wastes could be disposed of. These wastes
accumulate in the environment and cause pollution. Pollution is an undesired change in air, water, or soil that
adversely affects the health, survival or activities of humans or other organisms. Most pollution is a result of
human activities.
Two main types of pollutants: biodegradable (can be broken down by natural processes) pollutants and nonbiodegradable (cannot be broken down by natural processes) pollutants.
Biodegradable pollutant examples would include human sewage or stacks of newspapers. These items present a
problem when they accumulate faster than they can be broken down. Non-biodegradable pollutant examples
would be mercury, lead and some plastics because they do not break down easily.
Loss of Biodiversity
Biodiversity refers to the number and variety of species that live in an area. Only a fraction of the hundreds of
millions of species are alive today. All the others are now extinct. Extinction is a natural process, but during
the course of history, Earth has experienced mass extinctions (250 million years ago, as much as 95% of all
species became extinct).
Why should we be concerned with extinction of species? We depend on other organisms for food, for the
oxygen we breathe and for many other things. When a species becomes extinct, it is gone forever. We have
limited information on the current rate of extinction among the species alive today in comparison to organisms
in our past. Scientists believe that all species have potential economic, ecological, scientific, aesthetic and
recreational value. So, they believe it is in our best interest to preserve all organisms.
Lesson Reflection:
Complete the handout on environmental problems. List some of the problems at each of the levels.
Then, use your notes to give details of each of the environmental problems.
Assessment:
1. How do scientists relate Earth to a spaceship? Explain.
2. The growth of the human population has been a result of the agricultural revolution and the Industrial
Revolution. How has this growth impacted the environment?
Lesson Extension (Technology/Application/Connection to Real World):
What is the connection between natural resources and your clothes, the contents of your backpack, or some of
the common objects you find in the classroom?
As a group, make a list of the things you found and then determine if they are renewable or nonrenewable?
Object
Renewable
Nonrenewable