Habitat Fragmentation

1
Habitat Fragmentation

• Separation of wilderness areas from other
  wilderness areas
• Fragmented areas are like islands the smaller
  the fragment, the less biodiversity it will
  support

2
Figure 55.5 Fragmentation of a forest ecosystem
3
Figure 55.6 The history of habitat reduction and
fragmentation in a Wisconsin forest
4
Biotic and Abiotic Issues of Fragmentation

• Biotic
• -some organisms need large areas to gather food
• Ex. Lions
• Ex. Zebra
• -no migratory routes to re-establish populations
  lost due to natural disasters

• Abiotic
• -climate can change
• -can cause EDGE EFFECT
• (different conditions along the boundaries of an
  ecosystem)

5
Habitat Degradation

• Damage to habitat by pollution
• Three types of pollution air, water, land

6
Air pollution

• breathing problems
• irritation of membranes
• Burning of fossil fuels is biggest source
• Ozone layer is being broken down by CFCs
  (carbofluorocarbons) found in refrigerators and
  air conditioners as coolants this allows
  radiation to reach earth, causing genetic defects
  and cancer

7
Figure 54.27a Erosion of Earths ozone shield
The ozone hole over the Antarctic
8
Water Pollution

• Degrades aquatic habitats in streams, lakes, and
  oceans
• Excess fertilizers and animal waste get into
  streams and cause algal blooms
• Coral reefs are destroyed when silt covers the
  living coral and they cant photosynthesize or
  get to food
• Detergents, heavy metals, and industrial
  chemicals in runoff cause sickness and death in
  aquatic orgs
• Abandoned drift nets trap dolphins, whales, fish,
  sea turtles
• Acid precipitation is responsible for
  deterioration of forests and lakes, also damages
  plant tissues and interferes with plant growth.
• (sulfur dioxide from coal-burning factories and
  nitrogen oxides from exhausts combine with water
  vapor to form acid droplets of water vapor)
• Use of pesticides such as DDT gets into water

9
Figure 54.25 Biological magnification of DDT in
a food chain
10
Figure 50.3 Rachel Carson
Biologist, Writer, Ecologist
Silent Spring
11
Land Pollution

• Trash solid waste
• Made up of cans, bottles, paper, plastic, metals,
  dirt, spoiled food, etc.
• Average American produces 1.8 kg of waste daily
• Landfills take up space

12
Introduction of Exotic Species

• New orgs introduced into an ecosystem do not
  have any natural predators and is little
  competition with other orgs, so native species
  are at risk
• Exotics may take over niches of native species
  and eventually replace the native species
  completely

13
Greenhouse Effect and Global Warming

• In 1996, the United States was responsible for
  23 of the worlds carbon dioxide emissions --
  more than any other country.
• Carbon dioxide is the primary greenhouse gas,
  responsible for 60 of global warming
• http//www.epa.gov/globalwarming/kids/greenhouse.h
  tml

14
Conservation efforts

• Conservation Biology studies methods and
  implements plans to protect biodiversity
• legal protection of species
• habitat preservation
• (sustainable use,
• habitat corridors)
• reintroduction programs

15
What can you do?

• Be aware
• Reuse and recycle
• Turn off water and lights
• Carpool