4-4 Aquatic Ecosystems

Benthos

Organisms that live attached to or near the bottom of the ocean

kelp forest

A huge forest of giant brown algae in the coastal ocean

Three main types of freshwater wetlands?

Bogs Marshes Swamps

Aquatic ecosystems are primarily determined by what characteristics of the overlying water?

Dept Flow Temerature Chemistry

The two main types of freshwater ecosystems

Flowing-water ecosystems Standing-water ecosystems

What are the three main vertical divisions of the ocean based on the depth and distance from the shore?

Intertidal zone Coastal ocean Open ocean

What are the boundaries of the open ocean?

It begins at the edge of the continental shelf and extends outward.

What does the depth of the water determine?

It determines the amount of light that organisms can receive.

What are the boundaries of the benthic zone?

It extends along the ocean floor from the coastal ocean through the open ocean.

What are the boundaries of the coastal ocean?

It extends from the low-tide mark to the outer edge of the continental shelf.

Brackish water

It is a mixture of fresh and salt water.

Wetland

It is an ecosystem in which water either covers the soil or is present at or near the surface of the soil, at least part of the year.

Zonation

It is the prominent horizontal banding of organisms that live in a particular habitat.

The photic zone of the ocean

It is the well-lit upper layer

What does water chemistry primarily refer to?

It refers to the amount of dissolved chemicals—especially salts, nutrients, and oxygen—on which life is dependent.

Plankton

Plankton is a general term for the tiny, free-floating, weakly swimming organisms that occur in both fresh water and salt water.

Zooplankton

Planktonic animals Feed on phytoplankton

Phytoplankton

Single-celled algae Supported by nutrients in the water

Salt marshes

Temperate-zone estuaries dominated by salt-tolerant grasses above the low-tide line and by seagrasses under water.

How does the circulating water in a standing-water ecosystem affect the ecosystem?

The circulating water distributes heat, oxygen, and nutrients throughout the system.

Why is the coastal ocean often rich in plankton and many other organisms?

The continental shelf is often shallow enough to fall mostly or entirely within the photic zone, where photosynthesis can occur.

aphotic zone

The permanently dark zone below the photic zone is called the

What distinguishes a marsh from a swamp?

The presence of trees and shrubs in swamps is what distinguishes swamps from marshes.

What are mangrove swamps, and where are they found?

They are coastal wetlands that are widespread across tropical regions, including southern Florida and Hawaii.

Estuaries

They are wetlands formed where rivers meet the sea.

Where do flowing-water ecosystems originate?

They originate in mountains or hills, often springing from an underground water source.

Detritus

Tiny pieces of decaying plants and animals make up the that provides food for organisms at the base of an estuary's food web.

The benthic zone covers the ocean

floor