Biomagnification. Biodiversity The total sum of species in an area This is a natural resource and...

Post on 01-Apr-2015

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Biomagnification

Biodiversity

The total sum of species in an area

This is a natural resource and needs protection

Why ?

We get medicines, food and Diversity

Threats to biodiversity...

Human activity alters habitats

Extinction, endangered species

Invasive Species: new species that are introduced to an area that reproduces rapidly causing ecological change.

Biomagnification

Organisms at the top of the food chain have a higher degree of harmful substances then the organisms at the lower levels.

How does this occur?Farmers use a pesticide on crops

It does not biodegrade, so it washes into the streams

Algae absorbs it; small fish eat the algae

The bigger fish eat lots of small fish (therefore lots of pesticide)

Large birds eat the fish

The highest concentration of pesticides are found at this level.

Example: Bald eagles and their eggs

Rachel Carson discovered this

Must know figure 6-16 in book