Ecosystem Interactions

Esturay Ecosystem

Photo by CBF Member Steve Aprile,

Estuary – Where land and fresh water meet the sea

Estuary

Ocean

Nutrients wash into the

streams when it rains

Then flow into the estuary

Ocean water mixes in with

the freshwater

What is needed for a healthy ecosystem?• Producers need –

• Consumers need – Energy (sun), water, gasses (O2 and CO2), space, mineralsEnergy (food), water, gasses (O2), space, shelter

Why do animals need O2?Cellular Respiration

How do underwater animals (like fish) get O2?

Wave action, photosynthetic plankton, underwater

plants

Now begins the Notes at the bottom of page 10

Fertilizers – nitrates and phosphates

Rain washes fertilizers to the bay

Lots of fertilizer (nitrates) causesAlgal blooms

(another Algal bloom)

Algal blooms block the sun – Plants die. Algae also dies once the nutrients are used up.

Then, decomposers use up the O2

dissolved in the water

After all this algae dies, the decomposers will have lots and lots of food!

The increase in decomposers will use up all the oxygen, causing fish, crabs, oysters, and

other animals to die off.

Lack of Oxygen

DEAD ZONE&

Eventually, ecosystem

collapse!

CAUSE EFFECT Moderate amount of nitrates

Help the plants and algae grow

Too much nitrates Algae grows and reproduces out of control (Algal Bloom)

Too much algae in the water Block the sunlight – plants die

Too much dead plants and algae

Decomposers (bacteria) grow out of control

Too many decomposers (bacteria)

Use up all of the Oxygen

Not enough Oxygen in the water

Animals can’t survive

Too many dead plants and animals

Dead Zone – ECOSYSTEM COLLAPSE!

Videohttp://cbf.org/page.aspx?pid=433