Biodiversity Notes
Short for Biological Diversity
What does this mean?
Biological = Living organisms (plants and animals)
Diversity = variety
Species diversity
• number of species in a given
area.
– An island with 2 bird species and 1 lizard
species is more diverse than an island with
3 bird species.
– It’s numbers of species as well as
categories of organisms.
Lower Species Diversity
http://www.al.nrcs.usda.gov/technical/photo/for/mng
t/pine_plantation2.jpg
http://www.ipgri.cgiar.org/themes/human/images/Vegetation_Cuba.jpg
Higher Species Diversity
http://www.sagarprabhu.com/gif/rice5.gif
Genetic diversity
• Variations of genes
within a species.
– Lots of distinct populations
within a species (lots of
varieties of rice in India--all
from same species)
– Genetic Variation within the
population as a whole
(high in Indian rhinos, low
in cheetahs)
A few of the
hundreds of
rice varieties
found in
India.
Some genetic diversity
in potatoes …
http://www.potatoperspective.org/about_files/DSCN7746.jpg
• Variety of ecosystems
within an area.
Coniferous Forest
meeting a meadow
http://www.naturalhomemagazine.com/ba
ckissues/02-01/living_color/beach.jpg
http://cropandsoil.oregonstate.edu/HJA_mo/images/
Lookout_meadow_vs_forest.jpg
Ecosystem diversity
Ocean meeting
a beach
– Wisconsin has about 9
different ecosystems,
other states only have
about 3, some >14, etc.
– Very hard to measure due
to overlapping boundary
areas also called
ecotones.
bacteria, algae, fungi, mites,
millipedes and worms help cycle
nutrients
• Maintains air quality: plants
purify the air and filter harmful
particles out of the air
• Maintains water quality:
variety of vegetation reduces erosion
and purifies water by removing (using
or absorbing) nutrients and pollution
http://www.tropicalisland.de/KCH%20Sarawak
%20-%20Bako%20National%20Park%20%20Tropical%20rainforest2%201_b.jpg
http://www.srl.caltech.edu/personnel/krubal/rainforest/Edit560s6/
www/images/plants/fngcone1.jpg
• Maintains soil quality: healthy
http://www.pondsaway.com/images/wetlands1.jpg
Importance of Biodiversity:
Importance Continued …
• Pest control: most crop pests
Intercropping
cocoa plants
with coconut
trees.
become resistant to synthetic
pesticides
• Pollination and crop
production: More than 1/3 of
world’s crops rely on healthy
pollinators
• (Potential) Medicines: many
current and possible future
medications found in areas with
high biodiversity
http://images.jupiterimages.com/commo
n/detail/75/81/22568175.jpg
http://www.bugwise.net.au/images/25
0/pollination_002.jpg
can be controlled by other
organisms for a longer period of
time – helpful because many pests
5 Threats of Biodiversity
• Habitat
destruction/fragmentation
• Invasive species
• Population growth
• Pollution
• Overconsumption
Habitat Destruction
•Changing a habitat to suit human needs…for
housing, farming, etc.
•This displaces
animals/plants.
As the human
population
grows, so does
habitat
destruction!
Fragmentation
• Breaking up large
habitats into smaller
habitats.
• Creates an “edge” habitat
where “inner” habitat
used to be. Some plants
and animals cannot
adapt to these changes.
http://www.nature.org/wherewework/northamerica/states/illinois/i
mages/ozark_frag.jpg
Invasive Species
Any organism that
has been relocated
somewhere other
than its original
habitat.
Oftentimes,include:
invasive species
Synonyms
out-compete native species
resulting inspecies,
disruption
of the
Introduced
nonecosystem
andexotic
food chain.
native
species,
Many native organisms are
species
and
alien species…
becoming
endangered
by this!
Zebra Mussel
Asian Beetle
Population growth of Humans
 Increasing population
means greater demand for
food, shelter, fuel and
water.
 This often leads to habitat
loss, pollution, resource
scarcity and
overconsumption (in areas
with enough money)
 Humans are coming into
greater (more frequent)
contact with previously wild
areas with high biodiversity
http://www1.istockphoto.com/file_thumbview_approve/
2222903/2/istockphoto_2222903_crowded_city.jpg
http://www.chbr.noaa.gov/categories/stressors/image
s/pollution_sm.jpg
Population expected to reach
8 billion by 2020
Pollution
o Pollution can alter the habitat to the point where
some plants and animals will not be able to
adapt.
o Global Climate Change--many species are
intolerant to changes in temperature--affects
feeding relationships and breeding patterns.
o Acid rain/Air pollution-these types of issues
do not respect borders. US acid rain fell in
Canada destroying sugar maple forests which
upset the amount/quality of maple syrup
produced.
Overconsumption
 Individuals consuming way more
resources than needed to survive –
sometimes more than is needed for a
high standard of life
 Industrialized nations make up 25%
of the world’s population, but use
75% of its resources.
 US makes up only 5% of world’s pop-causes 33% of world’s pollution!