Environmental Systems- The Water We Use

desalination

the process of removing salt from water

groundwater overdraft

the removal of groundwater exceeds the rate at which it is replenished

water intoxication

an imbalance in electrolyte levels caused by consuming too much water

potable water

water that is drinkable without risk of immediate or long term harm

Which of the following is true about Earth’s supplies of freshwater?
a.
Most liquid freshwater is stored in rivers and lakes.
b.
Groundwater is a significant reservoir of liquid freshwater.
c.
Liquid freshwater is about half of all the water on Earth.
d.
None of the above.

b. Groundwater is a significant reservoir of liquid freshwater.

The most common source of water contamination is _______.
a.
sewage
b.
pesticides
c.
fertilizers
d.
none of the above

a. sewage

Which of the following activities depend upon the availability of supplies of freshwater?
a.
agriculture
b.
bathing
c.
drinking
d.
all of the above

d. all of the above

Identify what constitutes the defining characteristic of potable water.

The defining characteristic of potable water is that it can be consumed without risk of harm. Potable water is of a sufficiently high quality and purity that it lacks pathogens or contaminants that might otherwise pose a hazard to humans.

Which of the following would be expected to have plentiful access to potable water?
a.
Africa
b.
China
c.
Europe
d.
South America

c. Europe

Describe the most significant restriction on access to potable water around the world.

Around the world the most significant restriction on access to potable water is money. While access to raw water sources, clean or otherwise, is important, the purification process itself is expensive. Once water has been rendered potable, it is important that it be delivered without reintroducing contamination. The most convenient way to deliver potable water is through underground pipes, which requires expensive infrastructure.

Explain why water is critically important to most facets of human life.

Not only is water necessary for the physical survival of humans, but many, if not most, human activities also make use of it. Agriculture is critically dependent upon continual supplies of freshwater. Human households also use freshwater daily for cleaning and laundry as well as for transporting sewage to waste treatment plants.

Which of the following is not a risk factor for water intoxication?
a.
a low body mass
b.
heat stress
c.
resting
d.
overexertion

c. resting

Explain the relationship between overpopulation and diminishing water supplies.

As human populations grow they consume more water, not just by drinking, but through all of the other human activities that require freshwater such as agriculture, bathing, cleaning, etc. Overpopulation, therefore, can lead to overconsumption as populations use more water than an area can support and replenish sustainably.

Explain why the amount of water a person needs to survive can be highly variable.

The amount of water needed to sustain a person is highly variable because it depends upon not only the temperature and humidity of the environment where they live but the level of physical activity they engage in as well. People engaging in low levels of activity in cool temperate climates will need less water to survive than people engaged in highly strenuous activity in hot, dry climates.

Which of the following best describes the availability of freshwater on Earth?
a.
Less than 1% of Earth’s water is liquid freshwater.
b.
More than two thirds of Earth’s freshwater is stored in glaciers and icecaps.
c.
99% of liquid freshwater on Earth is stored as groundwater.
d.
All of the above

b. a tiny fraction of Earth’s freshwater

Lakes and rivers constitute _______.
a.
87% of freshwater
b.
a tiny fraction of Earth’s freshwater
c.
a majority of Earth’s freshwater
d.
a majority of water on earth

b. a tiny fraction of Earth’s freshwater

Which of the following best explains why humans need constant supplies of fresh water?
a.
Humans need a constant supply of water to provide them with essential vitamins.
b.
Humans need a constant supply of water to maintain proper hygiene.
c.
Constant supplies of freshwater are needed because body water is continually being lost.
d.
Constant supplies of freshwater are not actually necessary for survival.

c. Constant supplies of freshwater are needed because body water is continually being lost.

The defining characteristic of potable water is that it _______.
a.
is used as tap water
b.
can be used for washing and irrigation
c.
can be used and consumed without risk
d.
is delivered through pipes

c. can be used and consumed without risk

Which of the following is least likely to have difficulties with economic access to potable water?
a.
Zimbabwe
b.
Australia
c.
India
d.
None of the above

b. Australia

Which of the following is not an option for solving the world water crisis?
a.
desalination
b.
finding new sources of freshwater
c.
reducing overconsumption
d.
wastewater treatment plants

b. finding new sources of freshwater

Which of the following is a consequence of water polluted by human sewage?
a.
pathogens
b.
disease vectors
c.
high levels of contaminants
d.
all of the above

d. all of the above

Ocean water is sometimes referred to as saline water as it contains significant concentrations of dissolved salts

True

Which of the following most significantly determines a communities’ access to potable water?
a.
access to clean raw water sources
b.
the availability of money
c.
local drought conditions
d.
the level of industrial development

b. the availability of money

Which of the following human activities do not require water?
a.
agriculture
b.
household chores
c.
industry
d.
none of the above

d. none of the above

The human body does not constantly lose water through _______.
a.
respiration
b.
digestion
c.
perspiration
d.
urination

b. digestion

Access to potable water is most heavily limited by _______.
a.
money
b.
precipitation
c.
raw water supplies
d.
climate

a. money

Potable water delivery systems are characterized by _______.
a.
high infrastructure costs
b.
aqueducts
c.
glass bottles
d.
rivers

a. high infrastructure costs

Which of the following best explains the importance of water to humans?
a.
Water is essential for sustaining human life.
b.
Water is important for shipping and trade.
c.
Water is a valuable, profitable commodity.
d.
All of the above

d. All of the above

Which of the following best describes the availability of freshwater on Earth?
a.
Less than 1% of Earth’s water is liquid freshwater.
b.
More than two thirds of Earth’s freshwater is stored in glaciers and icecaps.
c.
99% of liquid freshwater on Earth is stored as groundwater.
d.
All of the above.

b. More than two thirds of Earth’s freshwater is stored in glaciers and icecaps

In developed nations, the water delivered to homes by pipe is generally potable.

True

The principle reason that most of North America and Europe do not have difficulties with access to potable water is their wealth.

True

The world’s supply of freshwater is increasing.

False

There are _______ mi3 of water stored in streams and rivers.
a.
2,000,000
b.
60,000
c.
300,000,000
d.
7,000,000

…

Water intoxication occurs when _______.
a.
the body’s electrolytes are out of balance
b.
a person has a high body mass
c.
in people engaged in low-impact activities
d.
all of the above

a. the body’s electrolytes are out of balance

Drinking non-potable water does not carry significant health risks.

False

Most people in cities get their water _______.
a.
by supplying it themselves
b.
by delivery through pipes
c.
through private suppliers
d.
all of the above

b. by delivery through pipes

The amount of water a body requires for survival is dependent upon the climate and the individual’s level of physical activity.

False