Hi, my name is Timmy. I live in the Pacific Ocean. This is one of the four large parts of the Global Ocean!

And I'm Melvin!

Our earth has two aquatic life zones. These are places in water where different animals live. The water can be freshwater or saltwater.

Me and my family live in a saltwater zone. The whole ocean is saltwater! The ocean has huge aquatic biodiversity.

Hi Timmy! What is aquatic biodiversity?

Hi Melvin, what a good question! Aquatic biodiversity is the variety of life and communities of lving things in freshwater and saltwater areas.

Areas with more organisms can cause greater biodiversity.

But Timmy, why do some areas of the ocean contain more organisms than other areas?

Thanks for asking Melvin! Temperature, dissolved oxygen content, food availability, and availability for photosynthesis all affect how many organisms are in an area.

Shallow or deep water can cause the temperature to change. Global warming also can cause the surface water temperature to rise.

Plants that release oxygen in the ocean as well as oxygen that gets absorbed from the atmosphere affect the dissolved oxygen content.

In aquatic zones, photosynthesis mainly happens in the shallow parts of the water where sunlight can penetrate. 

This is called the Euphotic zone. Depending on the turbidity (cloudiness of water), this zones depth can change. If the water is really cloudy due to excess nutrients, the sun cannot go through the water as deep.

Turbidity decreases aquatic biodiversity because it makes it harder for plants to obtain light and for fish to get food. This causes a lot of organisms to die.

The coastal zone is shallow, warm water that has a lot of nutrients and has a ton of marine species.