Water to drink,….
Farmland and water for crops,…
Roads to drive on…
And recreation.
And each of these things
impacts the plant, animal, and
insect species
of the Everglades, by reducing
available land and habitat, and
bringing other unintended
consequences.
Example: The largest threat to the West
Indian Manatee is boat propellers.
Threat Three: Pollution
• “Pollution” refers to any alteration of the
natural environment producing a condition
that is harmful to living organisms.
• Pollution may occur naturally (such as when
a volcano spews sulfur dioxide), but the
term usually refers to some of the effects of
human activities; such as automobile
exhaust emissions, oil spills, industrial
wastes entering the water supply, improper
disposal of solid wastes, and so on.
Oil Spill
Sometimes pollution
takes the form of an imbalance in the
levels of nutrients like nitrogen or
phosphorous. Excess nutrients may
enter water environments as runoff from
agricultural or other operations.
Sometimes a change in nutrient levels causes
algae to grow in number (straining the
resources of the water) or to become harmful to
animals and people.
Pfiesteria –Toxic Phase
Fish Killed By Pfiesteria
Sometimes pollution can
spread up a food chain and
bio-accumulate in the tissues
of species that are part of the
chain.
Bioaccumulation
• Refers to the process in which industrial
waste, toxic chemicals, and the like
gradually accumulate in living tissue.
Case Study in Harmful Bioaccumulation:
Bald Eagle
The use of the pesticide DDT was one cause in the
decline of North American Bald Eagle populations.
This frog’s deformation was probably caused by
pervasive pollution, to which amphibians are very
sensitive. Some think this type of deformation may
be linked to a hole in ozone layer.
We’ve seen how trade,
development, and pollution
affect individual species, but
what about “ecosystems”?
Ecosystem
A complex community of
organisms and its
environment functioning
as an ecological unit
An ecosystem has living….
….and non-living components.
Ecosystems exist in natural
balance among their
interdependent parts.
For example, the term “food chain” refers to
the relationship among different parts of an
ecosystem in which some derive food from
others.
There are many such relationships
within and among ecosystems. The
future of one species may be linked to
the future of all other species.
The whole world can be thought of
as one big ecosystem.
Ecosystem Case
Study:
Tropical Rainforests
Where are tropical rainforests
found?
The Amazon Rainforest
Ecosystem
The Amazon River and Rain Forest is in
South America
The Amazon River is very deep and wide—deeper and wider
than the Mississippi River that bisects our own continent.
The River is home to many
animal species
Piranha
Amazon River Dolphin
Tetra
Caiman
Matmata Turtle
The Amazon
Rainforest developed around
the Amazon River.