Notes: Human Impacts on the

Environment

What is biodiversity?

5.1 Biodiversity

Biodiversity is the variety of life in an area

determined by the number of different

species in that area.

Chapter 5 Biodiversity and Conservation

Biodiversity increases the stability of an

ecosystem and contributes to the health of

the biosphere.

Biodiversity A healthy biosphere provides

many services to humans and

other organisms that live on

Earth.

Green plants provide oxygen

to the atmosphere and

remove carbon dioxide.

Natural processes provide

drinking water that is safe for

human use.

Biodiversity and Conservation

Overexploitation

Bison

Ocelot

Rhinoceros

Rhinoceros

Cause: Overcollecting, overhunting, and

overfishing of native plants and animals

Effect: Increases extinction rates; 2nd greatest

THREAT to biodiversity

Ocelot

5.2 Threats to Biodiversity

Chapter 5

Biodiversity and Conservation

Habitat Destruction or Loss

Cause: Poisoning

lakes, destroying

forests for wood,

clearcutting land.

Effect: Threatens

native species and

upsets the balance of

nature; GREATEST

threat to

biodiversity

clearing of tropical rain forests

cutting forests for real estate

5.2 Threats to Biodiversity

Chapter 5

Biodiversity and Conservation

Pollution

Cause: Pollution, garbage,

and atmospheric changes

due to burning fossil fuels

Effect: Poor air quality; loss

of species due to water

contamination; less clean

drinking water

5.2 Threats to Biodiversity

Chapter 5

Garbage fields in ocean

Poor air quality

Soil pollution

Biodiversity and Conservation

Acid Rain

Coal-burning power plants

cause the pH in rain to be

more acidic

Poisons lakes; destroys

leaves and bark of trees;

changes soil pH; damages

buildings and cars

5.2 Threats to Biodiversity

Chapter 5

Kills forests in

eastern U.S.

Biodiversity and Conservation

Eutrophication

Cause: pollution flows into

waterways from soil runoff, causing

extensive algae growth.

Effect: The algae use up the

oxygen supply which kills fish and

other plants

Red Tide in Florida

Algae blooms in lakes

5.2 Threats to Biodiversity

Chapter 5

Biodiversity and Conservation

Introduced Species

Cause: Nonnative species that are either intentionally

or Unintentionally transported to a new habitat

Effect: Take over their new habitat killing other

animals or plants.

5.2 Threats to Biodiversity

Chapter 5

Fire Ants

Kudzu

Soil Erosion

Cause: over farming,

logging, construction,

5.2 Threats to Biodiversity

Effect: lowers soil fertility;

threatens agriculture and

homes

The Dust Bowl

Landslides

Cause: Burning fossil

fuels and killing forests

Effect: Global climate

change; melting of polar

ice caps; drought;

threatens plants and

animals

5.2 Threats to Biodiversity

Greenhouse Effect

2017: hottest year on record

Cause: Use of CFCs

destroys the ozone

layer which blocks UV

rays

Effect: higher incidence

of DNA mutation rates

in all species

5.2 Threats to Biodiversity

Ozone

Skin cancer rates increasing

Resources that are replaced by natural

processes faster than they are consumed

are called renewable resources.

Biodiversity and Conservation

Resources that are found on Earth in limited

amounts or those that are replaced by natural

processes over extremely long periods of time

are called nonrenewable resources.

5.3 Conserving Biodiversity

Chapter 5

Biodiversity and Conservation

Bioremediation

The use of living

organisms, such as

prokaryotes, fungi, or

plants, to detoxify a polluted area is called

bioremediation.

5.3 Conserving Biodiversity

Chapter 5