Transcript What causes the loss of biodiversity?

Biodiversity
Biodiversity
 The variety of life in an ecosystem.
Biodiversity increases as
you near the equator
3 most diverse biomes:
 Coral Reef
 Tropical Rainforest
 Wetlands Marsh
Why is Biodiversity
important?
 Beautiful and scenic
 Good for our health and an ecosystem’s
health
 (diet, medicines, and disease prevention)
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Loss of biodiversity
Extinct species
 A species once present on Earth but has
died out
Endangered species
 A species in danger of becoming extinct.
http://webecoist.com/2008/11/03/strange-rare-bizarre-endangered-flowers-plants-and-trees/
Threatened species
 A species likely to become endangered in
the near future.
What causes the loss of
biodiversity?
“HIPPO”
 Habitat Loss
 Invasive Species
 Poaching
 Pollution
 Over population
by humans
1. Habitat Loss
 Deforestation
 Slash and burn
Makes soil
temporarily more
fertile for farming
But rain forests
have nutrient poor
soil.
Negative Effects of
Deforestation
 Loss of habitat – crowds out species
 Increases levels of CO2 –
contributing to global warming
Encroachment
 Slowly moving into a species’ habitat
 Examples
 Road building & farming and housing
http://www.youtu
development
be.com/watch?v=
hllU9NEcJyg
2. Invasive Species
 Species that are
introduced into an
environment they are not
originally from
 Synonyms for exotic: alien,
feral, invasive, introduced
http://abcnews.go.com/US
/3000-invasive-goldfishthreatening-colorado-lakeecosystem/story?id=3013
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Cane Toads
 Released on purpose to kill
cane beetles
 Skin contains deadly toxins
 Practically no predators
 101 have turned into 200
million over 70 years
http://en.wikipedia.org/wiki/Bart_vs._Australia
Fire Ants
 Stowed away on ship to
Alabama
 Sting feels like burn
 Kills native insects
Killer Bees
 More aggressive honey bees
 Escaped from lab in Brazil
 Kills native bee species
Non-harmful invasive
species
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Wheat
Rice
Dogs
Cats
Horses
Pigs
Cows
Goats
How do they arrive?
Invasive species in FL
A Burmese
python
attempted
to eat an
alligator
http://www.biosecurity.govt.nz/enter
What’s the problem?
 Crowd out native
species
 No predators
 Decreases
biodiversity
3. Poaching
 Illegal hunting (killing)
OR
 Illegally removing a species from its
habitat
Poached Species
 Big Cats – Fur
 Elephants – Ivory
 Rhinoceros – Horns
 Orangutans – Pets
 Macaws – Pets
“In 2005 there were nearly 88,000
mammals, 1.3 million reptiles and 203
million fish imported illegally into the
United States.” -Reuters
Poaching
http://abcnews.go.com/Technology/wireStory?id=7513626
4. Pollution
 Water Pollution
 Air Pollution
 Ground Pollution
Water Pollution
 Pesticides
 Fertilizers
 Mercury
Pesticide Use
 Pesticide= chemicals
used to kill a pest
(rodent, insect,
fungus, etc.)
 Runoff with rainwater
puts it into local water
systems.
 Disrupts aquatic food
chains
DDT
 Pesticide used to kill mosquitoes
 Blamed for decline in bird of prey
populations
 Fish in polluted water eaten by birds
 Travels up the food chain
 Top predators (eagles, peregrine falcons)
affected most
 These birds lay eggs with thin shells
 U.S. banned DDT in 1972
 DDT still used in tropical locations to fight
malaria
 Some oppose ban due to DDT’s ability to
fight malaria
Fertilizer Use
 Runoff into
lakes
 Causes rapid
algae growth
(algae bloom)
 Algae blocks sunlight and….
 Plants die (less oxygen)
 Decomposers break down dead
plants (& use up oxygen)
 No oxygen available to other
animals and they “suffocate”
Phytoplankton Bloom
Mercury
 Mercury released into the air when burned,
and mixes with rainfall to get into the water.
 Found in high quantities in fish
 Can damage nervous and reproductive
systems (Pregnant women and young kids
at highest risk)
Hatters used mercury to
shape felt hats and often
were poisoned. “Mad as a
Hatter” references this.
Mercury
can
accumulate
in the food
chain.
 Mercury is
often
combined
with other
metals for
fillings
(ADA says
this is safe)
Air Pollution
 Pollutants released into air usually from
burning fossil fuels
Air Pollution causes…
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Global warming
Ozone depletion
Acid Rain
Carbon Monoxide
poisoning
Ground Pollution
 Soil becomes
polluted when air
pollutants drift to the
ground or when water
leaves pollutants
behind as it flows
through the soil.
5. Over Population of
Humans
Population numbers
http://www.ted.com/talks/hans_rosling_on_global_population_growth
Overpopulation
 As more humans are added to our
planet, the demand for natural resources
(for energy, food and shelter) increases
and more land is cleared for
development.
http://www.chrisjordan.com/current_set2.php?id=11
Review
1. What is biodiversity?
2. Why is biodiversity important in an
ecosystem?
3. What five actions cause a loss of
biodiversity? (HIPPO- spell them out)
4. Think about it- What could humans do to
reduce the loss of biodiversity? Describe
at least two ways humans could help
protect biodiversity.