2. Let’s first look at what makes a resource
renewable or nonrenewable.
Renewable resources are those that can
be replaced in a short amount of time.
Nonrenewable resources are those that
cannot be replaced in a short amount of
time.
3. Let’s consider these natural resources:
Rocks, animals, plants, soil, clean water,
crude oil, coal, natural gas, oxygen in
the air?
Which of these natural resources can be
replaced in a short amount of time and
which cannot?
4. What about plants? They undergo a life
cycle. Most produce seeds and are replaced
every year. They can be replaced in short
amount of time.
Animals also reproduce through a life cycle.
Some animals such as mice take a few weeks
to form before being born. Others like
elephants develop within their mothers for
two years before they are born. A few
weeks to two years is also a pretty short
amount of time.
5. Water can never be made again but it can be
“replaced” (cleaned) by nature. The main
way nature cleans dirty water in through the
water cycle.
When water evaporates, it leaves all the
“dirty” stuff that was dissolved in it behind.
As a result, the water that falls as rain, snow
or sleet is pure clean water.
The water that evaporates from the oceans
and lakes generally returns to the land as
precipitation within a few weeks—really a
short amount of time.
6. Now what about the oxygen in the air that
we need to survive?
Plants take in carbon dioxide and replace it
with oxygen in a very short period of time,
probably seconds.
7. So far we established that animals, plants,
oxygen and water can be replaced in a
short amount of time.
Therefore, we can say that animals, plants,
oxygen and water are all
a. nonrenewable resources
b. renewable resources
8. What about soil?
Remember soil is formed through the
weathering and erosion of rocks.
The United States Department of Agriculture
says that it takes about 1,000 years to make
an inch of soil.
One thousand years seems like a long
time.
9. Before we decide whether soil is a renewable
or nonrenewable resource let us look at how
long it takes for fossil fuels and the minerals in
rocks to form.
The three fossil
fuels--crude oil, coal
and natural gas--
take millions of
years to form from
the remains of
plants and animals.
10. It appears that Earth was created from minerals
that may have been formed billions of years ago
when a “dying” star exploded. From these minerals
we get many useful things like metals and sheet
rock.
11. So although one thousand years seems like
a long time, compared to millions and
billions of years, it is a relatively short
period of time.
As a result, soil is considered a renewable
resource—one that is replaced in a short
period of time.
On the other hand, minerals in rocks and
fossil fuels would be considered
a. renewable resources
b. nonrenewable resources
13. So what are the
natural resources
About 1,000 years to
that can be
make one inch replaced in a
relatively short
amount of time ?
And what are the ones that cannot be replaced
in a relatively short amount of time or at all?
14. Notice that the renewable resources are all
renewed through a cycle:
•plant life cycle
•animal life cycle
•water cycle
•carbon-dioxide oxygen cycle
•rock to soil back to rock cycle
16. Carbon dioxide and oxygen are part of the
carbon cycle in which
• plants take in carbon dioxide and
give off oxygen and
• animals take in oxygen and give off
carbon dioxide
Carbon dioxide
to oxygen back
to carbon
dioxide
17. Rock can be weathered and changed to soil.
Sometimes soil that is deposited in water can
be changed into sedimentary rock.
Rock to soil
Soil to rock
18. Water in the oceans and lakes evaporates,
condenses as clouds and falls back to Earth
as rain, snow or sleet.
Water
cycle
This is one
way nature
cleans our
water.
library.thinkquest.org
19. So all of the renewable resources occur
in cycles that allow them to be
renewed in a relatively short amount
of time—plants, animals, oxygen in the
air, water and soil.
20. Place the resources in the correct category:
coal, beans, copper, gold, cattle, natural
gas, soil, water, crude oil, oxygen.
Renewable Resources Nonrenewable Resources
beans coal
cattle copper
soil gold
water natural gas
oxygen crude oil
21. In conclusion, which of these is a true
statement:
a. Everything we use comes from natural
resources.
b. A few things we use come from natural
resources.
c. Many things we use come from natural
resources.
d. None of the things we use comes from
natural resources.