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 pollutiontakes 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.

Bald EagleCase Study in Harmful Bioaccumulation:

The use of the pesticide DDT was one cause in thedecline 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 RainforestsTropical 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 widerthan 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.