Download Chapter 5

Conserving Biodiversity (5.3)
State Standard
SB4D. Assess and explain human activities that
influence and modify the environment such as
global warming, population growth, pesticide
use, and water and power consumption.
What trend
about
resource use
does the
graph reveal?
Chapter 5
Biodiversity and Conservation
Natural Resources
 In today’s world there
is a high demand for
natural resources
 The consumption
rate of natural
resources is not
evenly distributed
 Natural Resources are categorized as either
renewable or nonrenewable.
Chapter 5
Biodiversity and Conservation
Natural Resources
 Nonrenewable resources are found on Earth
in limited amounts or those that are replaced
by natural processes over extremely long
periods.
Examples:
• Tin, silver, gold uranium, copper (limited amounts)
• Phosphorous (recycled slowly)
• Topsoil (forms slowly)
• Fossil fuels (form slowly)
Chapter 5
Biodiversity and Conservation
Renewable Resources
 Renewable resources are replaced by
natural processes faster than they are
consumed.
Examples:
• Plants
• Crops
• Animals
• Water
• Various types of energy
--wind
--water
--hydroelectric dams
Chapter 5
Biodiversity and Conservation
Water & Power Consumption
 Human population growth &
economic development are driving a
steadily increasing demand for water
& power supplies.
 While there is no shortage of water
globally, much of it is inaccessible
for human use and unevenly
distributed.
 More power is required to access
water and treat it so that it can be
used.
Chapter 5
Biodiversity and Conservation
Water & Power Consumption
 The negative
environmental effects
of burning fossil fuels
calls for development
of & use of
environmentally
friendly sustainable
energy sources.
Chapter 5
Biodiversity and Conservation
Natural Resources
 Sustainable use means using resources at a
rate in which they can be replaced or
recycled while preserving the long-term
environmental health of the biosphere.
Chapter 5
Biodiversity and Conservation
Threats to Biodiversity
Pollution
 Pollution and atmospheric
changes threaten biodiversity
and global stability.
 Pollution is the
contamination of soil, water,
or air as a result of human
activity.
 Pollution has increased as
countries have become more
industrialized.
Chapter 5
Biodiversity and Conservation
Threats to Biodiversity
Air Pollution & Global Warming
 The measured
increase of CO2 in the
atmosphere is largely
due to burning of
fossil fuels.
 As CO2 levels have
increased, the
average global
temperature has
increased
Chapter 5
Biodiversity and Conservation
Threats to Biodiversity
Air Pollution – CO2 & Ozone
 Excess CO2 can contribute to the Greenhouse
Effect (where gases in the atmosphere trap
radiant energy from the sun, causing the earth to
stay warm)
 Release of CFCs from making coolants &
Styrofoam has thinned the Ozone layer, which
protects the earth from ultraviolet radiation
overdose
Chapter 5
Biodiversity and Conservation
Threats to Biodiversity
Air Pollution
 Also includes dust, smoke, ash, carbon
monoxide, sulfur oxides.
 Contains gases & particulates (harmful solids)
 Smoke, gas, & fog combine to form smog.
Chapter 5
Biodiversity and Conservation
Threats to Biodiversity
Air Pollution - Acid Precipitation
 Smog containing Sulfur and nitrogen
compounds react with water and other
substances in the air to form sulfuric acid and
nitric acid.
 Acid precipitation removes calcium, potassium,
and other nutrients from the soil, depriving
plants of these nutrients.
 Also damages crops, aquatic ecosystems, and
weathers buildings.
Chapter 5
Biodiversity and Conservation
Threats to Biodiversity
Pollution & Pesticides
 Biological magnification is
the increasing concentration
of toxic substances in
organisms as trophic levels
increase in a food chain or
food web. Ex: DDT
 Overuse of pesticides has
also caused a rise in
pesticide-resistant insect
populations (natural selection)
Chapter 5
Biodiversity and Conservation
Threats to Biodiversity
Water Pollution
• Caused by contaminants from sewers, industries,
farms, & homes, which enter water sources such
as lakes, rivers, groundwater, & oceans
Chapter 5
Biodiversity and Conservation
Threats to Biodiversity
Water Pollution - Eutrophication
 Eutrophication occurs when substances rich
in nitrogen and phosphorus (fertilizers) flow
into waterways, causing extensive algae
growth.
 The algae use up the oxygen supply during
their rapid growth and after their deaths
during the decaying process.
 Other organisms in the water suffocate.
Chapter 5
Biodiversity and Conservation
Threats to Biodiversity
EXTINCTION
 The gradual process of species becoming
extinct is known as background extinction.
 Mass extinction is an event in which a large
percentage of all living species become
extinct in a relatively short period of time.
Chapter 5
Biodiversity and Conservation
Threats to Biodiversity
EXTINCTION FACTORS
 The current high rate of extinction is due to the
activities of a single species—Homo sapiens.
 Humans are changing conditions on Earth
faster than new traits can evolve to cope with
the new conditions.
Chapter 5
Biodiversity and Conservation
Threats to Biodiversity
EXTINCTION FACTORS
 Overexploitation, or excessive use, of species
that have economic value is a factor increasing the
current rate of extinction.
 Bison
 Passenger pigeons
 Ocelot
 Rhinoceros
Rhinoceros
Ocelot
Chapter 5
Biodiversity and Conservation
Threats to Biodiversity
EXTINCTION FACTORS
- Habitat Loss
 If a habitat is destroyed or disrupted, the native
species might have to relocate or they will die.
 The destruction of habitat, such as the clearing
of tropical rain forests (deforestation), has a
direct impact on global biodiversity.
Chapter 5
Biodiversity and Conservation
Threats to Biodiversity
EXTINCTION FACTORS
- Habitat Loss
 The declining
population of
one species
can affect an
entire
ecosystem.
Chapter 5
Biodiversity and Conservation
Threats to Biodiversity
FRAGMENTATION OF HABITAT
 The separation of an ecosystem into small pieces
of land is called habitat fragmentation.
 The smaller the parcel of land, the fewer species it
can support.
 Fragmentation reduces the opportunities for
individuals in one area to reproduce with individuals
from another area.
 Carving the large ecosystem into small parcels
increases the number of edges—creating edge
effects.
Chapter 5
Biodiversity and Conservation
Threats to Biodiversity
INTRODUCED SPECIES
 Nonnative species that are either intentionally or
unintentionally
transported to a
new habitat are
known as
introduced
species.
 Introduced species often reproduce in large numbers
because of a lack of predators, and become
invasive species in their new habitat.
Chapter 5
Biodiversity and Conservation
Conserving Biodiversity
Biodiversity Hot Spots
 Currently, about seven percent of the world’s
land is set aside as some type of reserve –
especially where there are endemic species
and a large portion of the habitat has been
lost.
Chapter 5
Biodiversity and Conservation
Conserving Biodiversity
Corridors Between
Habitat Fragments
 Improve the survival of biodiversity by providing
corridors, or passageways, between habitat
fragments
 Creates a larger piece of land that can sustain
a wider variety of species and a wider variety of
genetic variation
Chapter 5
Biodiversity and Conservation
Conserving Biodiversity
Bioremediation
 bioremediation
 The use of living
organisms, such as
prokaryotes, fungi,
orplants, to detoxify a
polluted area is called
 EX:
. Bacteria cleaning up oil spills
Chapter 5
Biodiversity and Conservation
Conserving Biodiversity
Biological Augmentation
 Adding natural predators to a degraded
ecosystem is called biological augmentation.
Ladybugs help control aphid populations.
Photo courtesy of Nature’s Control