Transcript Biodiversity Review 2

BIODIVERSITY
the variety of life on Earth!
http://www.millan.net
Benefits of Biodiversity
• Clean air
• Food to eat
• Clean water
• Medicines
• Raw materials
• Recreational purposes
THREATS TO BIODIVERSITY
H -Habitat loss
I -Introduced species
P –Pollution
P –Population Growth
O –Over-consumption
BIODIVERSITY THREAT
Development of natural areas for cities or
habitat destruction
agriculture results in ____________________
http://www.simtropolis.com/idealbb/files/SG_ShoppingCenter.JPG
BIODIVERSITY THREAT
http://www.lubee.org/images/about-threats-1.jpg
Tropical rainforests are disappearing
at a rate of about 80 acres per minute.
http://www.abc.net.au/news/newsitems/200506/s1384632.htm
BIODIVERSITY THREAT
Changes in Brazilian rainforest over 30 years
The tropical rainforests once covered more
than 14% of the earth's total land surface,
but now cover less than 6%.
BIODIVERSITY THREAT
http://www.wri.org/biodiv/pubs_maps_description.cfm?ImageID=1553
Nearly half of the world's species of plants, animals
and microorganisms will be destroyed or severely
threatened over the next quarter century due to
rainforest deforestation.
____________________________
BIODIVERSITY THREAT
Splitting a habitat into smaller disconnected
pieces = _____________________
Habitat fragmentation
It results in small “islands”
of natural area isolated
from each other by crop
land, pasture, pavement,
or even barren land.
http://en.wikipedia.org/wiki/Habitat_fragmentation
BIODIVERSITY THREAT
One of most important threats to
biodiversity come from apparently
harmless plants or animals that
humans transport into new habitats =
_____________________
INVASIVE SPECIES
PREDATORS
New habitats don’t have ____________
and parasites that control the population
in their native habitats, so invasive species
INCREASE rapidly.
populations _____________
EXAMPLES OF INVASIVE SPECIES
http://psephos.adam-carr.net/countries/a/australia/images/australiamap.gif
24 rabbits turned loose for
hunting in 1859 in Australia,
reproduced at such a rapid
rate they have taken over
the continent.
Within 10 years they had
multiplied so rapidly, 2 million
rabbits a year could be shot or
trapped without any noticeable
effect on population.
http://en.wikipedia.org/wiki/Image:Wild_rabbit.jpg
EXAMPLES OF INVASIVE SPECIES
http://en.wikipedia.org/wiki/Image:Rabbit-erosion.jpg
They are believed to be
responsible for the
_______________
of 1/8 of
extinction
the mammal species,
unknown numbers of plant
species, as well as serious
________________
soil erosion. problems.
It is still a major problem and rabbit diseases have
been purposely introduced to try to control the
population.
http://www.csiro.au/communication/rabbits/qa1.htm
BIODIVERSITY THREAT
pollutants
The addition of ________________
= harmful materials that can enter the
biosphere through land, water or air
can also threaten biodiversity.
http://www.kidcrosswords.com/kidoutdoors/the%20environment/pollution_smokestacks.jpg
http://www.iol.ie/~carigeen/pollution.jpg
Example:
_____
DDT was first modern insecticide
It was cheap, stayed active for long
time, and kills many different insects
Used to control agriculture pests
and disease carrying
MOSQUITOES
_______________
http://www.michigan.gov/images/mosquito_65147_7.jpg
When DDT was sprayed, it
drained into rivers and
streams at LOW
concentrations.
http://www.ci.cypress.ca.us/public_works/stormwater_images/kids_watershed.jpg
DDT in the environment gets into
food chain is
organisms through the ___________,
stored in __________,
and
tissues
______________________.
doesn’t degrade
http://www.geocities.com/~greyhawk_1/sh_eagle-9.jpg
BIOLOGICAL MAGNIFICATION
______________________________
= the concentration
____________ of a harmful substance
increases
____________as
it passes to organisms at
higher trophic
_______________levels
in food chain or web.
Plants pick up
DDT from water
& store it
→
Herbivores eat
plants and store
some DDT
→
Carnivores eat
herbivores and
store more DDT
The wide spread use of DDT threatened
many species… especially fish eating
birds like osprey, brown pelican, and
bald eagles.
http://image10.webshots.com/11/3/94/67/2146394670011493049pwlCDV_ph.jpg
DDT causes birds to lay
fragile
eggs with ___________
shells so eggs would
break when sat on.
American Bald Eagle was declared
endangered in 1967. It has since been
“threatened”
reclassified as _____________________
http://www.kimball.k12.sd.us/Heroes%20Web%20Page/Pictures/Rachel%20Carson.jpg
In 1962, American biologist
Rachel Carson published the
_______________
book,_____________
Silent Spring which
told of DDT’s harmful effects.
The book led to a large public outcry and
banned
eventually resulted in DDT being _________
in the United States in the 1970’s
The book was one of the important events in
environmental movement
the birth of the _________________________.
WHAT DOES IT MEAN?
REMEMBER!
Everything is connected.
BIODIVERSITY is a measure
of the health of an ecosystem.
Image from: Pearson Education Inc, publishing as Pearson Prentice Hall ©2006
CONSERVING BIODIVERSITY
Wise management of natural resources =
__________________
conservation
Protecting endangered species requires
detailed information about
ecological relationships
__________________________
We can’t protect a species without
interacts
understanding how it ____________
with
the _________________.
ecosystem
CONSERVING BIODIVERSITY
Examples of efforts to keep a species from
becoming extinct:
Captive breeding
___________________
(raised and protected in zoos until
population is stable, then returned to wild
http://www.blackfootedferret.org/
CONSERVING BIODIVERSITY
Today
conservation
efforts focus on
protecting entire
ecosystems not
just individual
species
HOT
SPOTS =
______________
are places that are
MOST endangered
Image from: Pearson Education Inc publishing as Pearson Prentice Hall© 2006
WHAT CAN BE DONE?
• Set aside land for parks/preserves
• Research to understand
species/ecosystem
interactions
• Concentration of $
on HOT SPOTS to
maximize results for
$ spent
http://www.anselm.edu/homepage/jpitocch/genbios/piplosign6403.jpg