Lesson 4
Saving Resources
Chapter 6
Conserving Our Resources
Objectives
Describe practices used to conserve
Earth’s land, water, and air.
Discuss alternative energy sources and
methods of reducing pollution from fossil
fuels.
Main Idea
Conservation helps preserve Earth’s
resources and our environment.
How can we save
Earth's land, water, and air?
 People have researched and tested ways to
protect our precious resources such as land,
water, and air from waste and pollution.
 There are many ways to protect the soil.
 One way is to add humus to the soil after
harvesting crops or by adding manure to
fields to help plants grow.
 Farmers can rotate their crops so that the
same substances and nutrients aren't
removed from the soil year after year; other
crops can even add substances and nutrients
to the soil.
 Farmers trap runoff and prevent soil from
being washed or blown away by planting
trees across the top of a hill in rows, crops in
terraces, or grass between rows of crops.
Recycling
Recycling things such as paper,
glass, metals, and plastic can reduce
the amount of garbage in landfills.
Conserving Water
Water can be purified in water-treatment
or purification plants with chemicals,
filtration, and chlorine to kill bacteria.
Countries have passed laws to keep
wastes out of the oceans, limit catches of
fishing fleets, and/or set aside areas for
marine life.
Quick Check
Problem and Solution
What are some ways in which farmers
try to protect and conserve soil?
Farmers add fertilizers, rotate crops,
use terracing, and grow plants that
curb runoff between rows of crops.
Critical Thinking
How do wastes put into the oceans
affect people?
Fish that live in the ocean take in the
chemicals and wastes. The chemicals
and wastes can be passed along to
people who eat the fish.
How can we reduce the burning of
fossil fuels?
Supplies of fossil fuels
are limited because
they are nonrenewable.
People burn fossil fuels
to power their cars,
heat their homes, and
generate electricity.
Alternative Energy Sources
Scientists study alternative energy
sources which are ways that we can
create energy without using fossil fuels.
 Geothermal energy can be used to
heat homes and produce electricity.
 Wind, a major alternative energy
source, turn windmills (turbines) that
generate electricity.
The process of biomass conversion, where
biomass is taken to a biorefinery, produces
alcohol based fuels to generate electricity
and heat.
Examples are corn, grains, and sugarcane.
 Running water has always provided energy
in the United States through hydroelectric
plants at the bases of dams.
The Sun is the largest provider of energy;
it heats the atmosphere, causes wind to
blow, drives the water cycle, powers
plants' photosynthesis, and can be stored
in solar cells for later use.
Quick Check
Problem and Solution
How can people reduce their dependence
on fossil fuels?
Conserve energy and use more alternative
energy sources; buy energy efficient
machinery and appliances; lower
thermostats at night.
Critical Thinking
Which alternative energy source do you
think people would be most willing to use?
Explain the reason for your choice.
What are the 3 R’s?
 The 3 Rs are reduce, reuse, and recycle.
Reduce the amount of resources we use
by adjusting indoor temperatures;
reuse materials and products by not using
disposable items;
and recycle paper, plastic, metal, glass,
etc, which lessens the amount of garbage
and energy needed to produce new
products.
Millions of computers and electronics,
containing hazardous materials, are thrown
away, that should be reprocessed properly.
Quick Check
Problem and Solution
How does recycling help solve the problem
of pollution in the environment?
Recycling helps reduce the amount of new
materials that are made, reducing the
pollution that occurs during manufacturing.
It also reduces the pollution that results from
disposing of garbage, such as transporting
garbage and placing it in landfills.
Critical Thinking
How do you think solar cells might be
used to help air condition a home?
Some of the electricity might be used
directly during the day to run the air
conditioner, while some is stored in a
battery to use to run the air conditioner
at night.