Page 31 - Science Course 3 (Book 1)

Mo1-L3b: What are the Types of Aquatic Ecosystems?

Let’s Begin Key Concept

What are the Types of Aquatic Ecosystems?

Wetlands How do humans impact wetlands?
Wetlands are aquatic ecosystems that have a thin
layer of water covering soil that is wet most of the
time.

Wetlands contain freshwater, salt water, or both, and
are among Earth’s most fertile ecosystems.

Freshwater wetlands form at the edges of lakes and
ponds and in low areas on land.

Saltwater wetlands form along ocean coasts. Estuaries

More than one-third of North American bird species Estuaries are regions along coastlines where
use wetlands for nesting and feeding. streams or rivers flow into a body of salt water.

Most estuaries form along coastlines, where
freshwater in rivers meets salt water in oceans.

Salinity depends on rainfall, the amount of
freshwater flowing from land, and the amount
of salt water pushed in by tides.

In the past, water was
drained away from
wetlands to build homes
and raise crops, but today
many wetlands are being restored and preserved.

ESTUARY

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