Download Chapter 49: People and the Biosphere

Chapter 49: People and the Biosphere
Section 2: Pollution
Pollution

Materials released into the environment fall into two categories:
_________________________ and ________________________________

Materials that can be degraded, or broken down, by microorganisms into the
essential nutrients from which they were made are _______________________
o ________________________________

__________________________________ materials cannot be broken down by
natural processes or are broken down only very slowly
o ____________________________________________________________
o Once these materials are released into the environment, they remain
there for a long time – __________________________________
Biological Magnification

Sometimes pollutants affect the biosphere in ways no one expects

Many ______________________________________ pick up nonbiodegradable
pollutants from the ________________

They concentrate them and store them in their ____________________

When _____________________________________________, they too
concentrate and store these nonbiodegradable compounds in their tissues

When __________________________________________, the compounds are
further concentrated

At each step in a food chain, the compounds are concentrated more and more

In other words, the amount of the compounds in each organism in a food chain
________________________

This phenomenon is known as ________________________________________

Biological magnification occurs with many __________________________ and
___________________________________________
Air Pollution

The air supplies the _____________________ our cells need to metabolize food
and receives the waste products we give off as a result of our life processes

But the air also contains many other chemicals—chemicals that are not part of
the natural composition of the atmosphere
Smog

If you live in a city, you may be familiar with the dirty-brown haze called
_______________

Smog = _______________________________

Contains different pollutants in different places

The causes of smog also differ from one location to another

Weather conditions called ____________________________________________
can make smog a serious health hazard

Normally, cooler air is at higher altitudes than warmer air

The warmer air closer to the Earth’s surface contains ______________________

But because it is warm, it is _________________________ than cool air and
_______________

As it rises, it slowly _______________, and the pollutants it contains are carried
away by _________________

During an inversion, a layer of _____________________________________ is
trapped beneath a ____________________________________

Because the cool air is denser than the warm air above it, __________________
________________

As a result, the _________________________ are kept ____________________
_____________________

Temperature inversions can last for ______________, ____________, and even
__________________
Acid Rain

Certain pollutants in the air combine with ____________________________ to
form droplets of _______________

When these droplets fall to the Earth in rain, the rain is called ______________
______________

In many areas, the ___________________________ burned in factories and
power plants to generate energy contain large amounts of __________________

When sulfur is burned, it forms ________________________________

Sulfur dioxide dissolves in water to form a strong acid: ____________________
_________________

Sulfur dioxide is often carried on prevailing winds far from where it is produced

The effects of acid rain on the environment are numerous and serious to life

Acid rain damages ______________________________________________
The Greenhouse Effect

The amount of _________________________________ in the atmosphere is
________________________ as a result of human activity in the biosphere

Carbon dioxide is produced when carbon-containing fuels are burned

Carbon-containing fuels include _____________ and ____________________
as well as _____________________________ such as ____________, ________,
and _____________________________

Over the years, the burning of trees and fossil fuels for energy has released vast
quantities of carbon dioxide into the atmosphere

Energy from the _____________ is absorbed by the _______________ and
changed into ______________

Later, this energy is radiated back from the Earth to the ____________________

Carbon dioxide and other gases in the atmosphere absorb this heat energy
o ______________________________________

As levels of carbon dioxide in the air increase, more heat is absorbed and the
______________________________________________________

The effects of this global warming are unclear
o ______________________________________________________
o ______________________________________________________
Holes in the Ozone Layer

A layer of ___________________ exists far above the Earth in a part of the
atmosphere called the ____________________________ (10 – 30 miles above
the Earth’s surface)

Protects the Earth from harmful _______________________________________
from the sun

Without the protection of this layer, few living things could survive

Scientists have recently discovered that the ozone layer is becoming
_____________________ in certain places around the _________________
o _______________________________________________

The major cause of ozone depletion is a form of chemical air pollution that
results from the addition of ____________________________________ to the
air

Scientists predict that if the amount of UV radiation that reaches the Earth
increases, the frequency of certain diseases—such as certain forms of
__________________________—will also increase
Water Pollution

In the United States, billions of liters of fresh water are used daily
o ________________________________________________________

Although water is a renewable resource, there is a limited amount of fresh water

____________ of Earth is water

Only ___________ is fresh water
o Only a small portion is available for living things
o The greater portion is locked up in __________, mainly in polar ice caps
and glaciers

The most common sources of water pollution are ________________________,
____________________________, and _________________________________
Chemical Contamination

_____________________________________ can pollute water in two ways
o The chemicals can enter into ___________________________________
o Chemical wastes discarded on land can ___________________________
____________________________ and enter the ground water supply
Sewage Contamination

_____________________ consists of large quantities of wastes that contain
nitrogen compounds

These compounds are used by ____________________ in a process that
requires oxygen

If untreated sewage is added to rivers and streams, the number of bacteria
_____________________________________

These bacteria use up most of the available oxygen as they break down the
nitrogen compounds

Other organisms that live in the water may __________________________
because their supply of oxygen is depleted

In rural areas, where homes are far apart, sewage is usually treated in
________________________________

In a septic system, bacteria work on the sewage, reducing it to water that is
___________________________

This water seeps out of the septic system and into the __________________

In cities, sewage must be treated in ____________________________________

In special _________________, this sewage is broken down by bacteria

Once the bacteria have decomposed the organic matter, ___________________
that kill harmful microorganisms are added to the sewage and the treated water
is ______________________

Human sewage also contains many potentially harmful microorganisms:
_________________________________________________

Filter-feeding organisms, such as _______________ and __________________,
ingest the microorganisms and concentrate them in their tissues

When these shellfish are eaten, diseases such as ___________________,
____________________, and certain forms of __________________ can spread
Thermal Pollution

Many factories and power plants produce ______________ as a waste product

In the past, water from nearby rivers, lakes, or the ocean was used to
______________ such plants

The water was pumped through pipes in the cooling system, where it absorbed
heat

The heated water was then pumped back into the environment

In some cases, heated water has no harmful effects on the ecosystem

But often, heated water ______________________________________________

This kind of water pollution is called ___________________________________
Ocean Pollution

For centuries people have _________________________________________
into the oceans

Too many people produce too much waste, a great deal of which is
__________________________________

Plastics and other wastes dumped into the oceans may float around for months
or even years

Large cities continue to dump so much sewage into the oceans that it cannot be
degraded quickly enough

Often, some of this sewage ___________________________________________

Pollution __________________________________ is a serious matter

Some wastes dumped into the oceans—such as containers of disposable medical
items—wash back onto shore, threatening the health of beach-goers

Other wastes remain at sea, posing a hazard to ocean life
Oil Spills

Regardless of the cause, once oil is spilled, it is ___________________________
____________________

Oil slicks are deadly to marine animals that swallow the toxic oil or become
coated with it

Toxic chemicals in oil often __________________________ in those animals
that are not killed immediately

In most cases, these chemicals make the animal ___________________

Some of the chemicals that accumulate in animal tissue are potent
_____________________________ that may cause ___________________ in
the people who eat them