Biological Diversity and Conservation

Biological Diversity (Biodiversity)

Biodiversity refers to the variety of species in a specific area.

• Example: A rain forest has a greater amount of biodiversity than a cornfield would.
• Biodiversity increases as you move toward the equator. Why?

Importance of Biodiversity

Importance to nature:

• Populations are adapted to live with other populations in a community.
• Species depend on other species to survive.
• Example: flowers depend on bees and other insects to pollinate them.

Importance to people:

• Oxygen we breathe comes from plants.
• Food we eat comes from plants and animals.
• Some medicines come from living things.
• Clothing, wood, etc. all comes from living things.

Loss of Biodiversity can lead to...

Extinct species

• Occurs when the last organism of a species dies.

​

Woolly Mammoth

Dodo Bird

Saber tooth tiger

Endangered species

• Occurs when a species numbers become so low that extinction is possible.

Loss of Biodiversity can lead to...

Threatened species

• Occurs when a species numbers become so low that it is possible for them to become endangered.

Loss of Biodiversity can lead to...

Where are the Areas with large amounts of threatened species?

Why do you suppose this is?

North America, South America, India, and SE Asia

Large amounts of industrialization

Threats to Biodiversity

#1 reason for loss of biodiversity is HABITAT LOSS.

​

Areas of major loss include: Amazonian rain forest and coral reefs.

Habitat fragmentation is the separation of wilderness areas from other wilderness areas.

• Contributes to:
• Increased extinction of local species.
• Disruption of ecological processes.
• New opportunities for invasions by introduced or exotic species.
• Increased risk of fire.
• Changes in local climate.
• Can lead to geographic isolation (which can lead to genetic isolation...one species becomes two different species and can no longer interbreed).

Threats to Biodiversity

Edge of a habitat is where one habitat or ecosystem meets another.

• Examples: forest meets a field, water meets land, etc.

Edge effect is the different conditions that can be found along the boundaries of an ecosystem.

• Edges tend to have greater biodiversity because different habitats with different species are brought together.
• So when the edge is messed up...species are affected- they may move out or die out.

Threats to Biodiversity

Threats to Biodiversity

Habitat degradation is the damage to a habitat by pollution.

• Three types of pollution are:
• Air
• Land
• Water
• Acid precipitation (rain, sleet, snow, and fog with low (acidic) pH levels).
• Caused by sulfur dioxide from coal-burning factories and nitrogen oxides from automobile exhaust combining with water vapor in the air.

Increasing concentration of a harmful substance in organisms at higher trophic levels.

Biomagnification

Conservation biology is the study and implementation of methods to protect biodiversity.

• These methods include:
• Natural resource conservation
• Natural resources are those parts of the environment that are useful or necessary for living organisms.
• Species conservation
• Legal protection of species.
• 1973- U.S. Endangered Species Act
• Reintroduction and species preservation programs.
• Release organisms into an area where the species once lived.
• Captivity has saved several species from extinction.
• Example: Ginkgo tree

Conservation of Biodiversity

Habitat corridors are protected strips of land that allow the migration of organisms from one wilderness area to another.

Conservation of Biodiversity

• Plants or animals that have migrated to a place where they are not native.
• Reproduce rapidly
• New habitat lacks their natural predators.
• Example: cane toads

Invasive Species

Example in USA: Zebra Mussels

• Came on ships from Europe in 1980s.
• Spread through Great Lakes.
• Driving native species close to extinction.

​

​

Invasive Species

Example in USA: Kudzu

​

​