Aquatic Ecosystems

1
Aquatic Ecosystems

• Chapter 19
• Lesson 3

2
Types of Ecosystems

• Water takes up more than 70 of the Earths
  surface. That means that if you divided the Earth
  into ten equal parts, seven of those equal parts
  would be made of water.
• The water on earth is categorized into two
  groups freshwater ecosystems and saltwater
  ecosystems.
• Saltwater is water that has a lot of salt in it.
• Salinity is the amount of salt dissolved in
  water.
• Freshwater is water that contains very little
  salt.

3
Freshwater Ecosystems

• rivers streams,
• Rivers and streams have moving water. The water
  may be moving fast or slow.
• Streams are often clear and form underground.
• Rivers form when streams run together.

Biodiversity -Water-loving plants -Species adapt
to fast/slow moving water
Human Impact -People take out the
water -Hydroelectric dams stop water -Runoff a
source of pollution
4
Freshwater Ecosystem

• Ponds Lakes
• Ponds are shallow and warm and sunlight can
  usually reach the bottom
• Lakes are larger and colder where sunlight barely
  reaches the bottom

Human Impact -Humans fill-in ponds/lakes -Run-off
washes pollutants into water
Biodiversity -Plants surrounds ponds/lakes -Fewer
organisms live in deeper, colder water of lakes
5
Wetlands

• Aquatic ecosystems that have a thin layer of
  water covering soil that is wet most of the time.
• Contain freshwater, saltwater, or both
• Wetland trap sediments and purify water.

Biodiversity -Few trees live in saltwater
wetlands -Insects are abundant -More than 1/3 of
NAm birds species use wetlands -alligators,
turtles, frogs, snakes
Human Impact -Once drain off and built on -Now,
major preservation and focus on restoring wetlands
6
Estuaries

• Regions along coastlines where streams or rivers
  flow into a body of saltwater.
• Salinity depends on rainfall, freshwater flowing
  from land and tides.
• Protect coastal land
• Filter out pollution

Biodiversity -Many ocean animals lay their eggs
in estuaries -Many species of birds depend on
estuaries for breeding, nesting, and feeding
Human Impact -Filled in for land and destroys
natural habitats. -Exposed coastlines are prone
to coastal flooding and storm damage
7
Ocean Zones

• Oceans are the worlds largest ecosystem.
• Water is deeper is some places than in others and
  the water temperature also changes.
• The ocean is divided into three zones.
• Sunlight Zone
• Twilight Zone
• Dark Zone
• The deeper the water, the colder and darker it
  becomes.
• Most plants and animals can be found in the areas
  closer to the surface.

8
Saltwater Ecosystems

• Open Oceans from continental shelf to deep
  ocean.
• Photosynthesis can take place only where the
  sunshine reaches. Little in Twilight Zone and
  none in the Dark Zone/sea floor
• Decaying matter and nutrients float down

Biodiversity -Microscopic algae and other
producers are the base of most ocean food
chains. -Most animals live in light or twilight
zones -Dark zones have lava eruptions
Human Impact -Overfishing -Trash discarded on
cruise ships and from the land greatly impact
ocean life
9
Saltwater Ecosystems

• Ocean Coastal Oceans/Intertidal Zones is the
  ocean shore between the lowest low tide and the
  highest high tide.
• Sunlight reaches the bottom of shallow coastal
  ecosystems
• Nutrients washed in from rivers and streams
  contribute to high biodiversity.
• Intertidal species have adaptations for the
  extreme living conditions of low tide and heavy
  waves of high tide.
• Oil spills can destroy all living organisms.

10
Saltwater Ecosystems

• Coral Reef is an underwater structure made from
  outside skeletons of tiny, soft-bodied animals
  called coral.
• Most are in shallow tropical oceans
• They protect coastlines from storm damage
• Provide food and shelter for many animals
• Pollution, overfishing, and harvesting threaten
  coral reefs.

11
Animals Found in Saltwater Ecosystems
crustaceans
fish
sharks
sponges
penguins
whales
12
Animals Found in Freshwater Ecosystems
Grebe
Turtle
Trout
Puffer fish
Otter
Pelican
Bullfrog
13
The largest source of freshwater on earth is ice
sheets, glaciers, and icebergs. The Great Lakes
are the largest fresh water on the planet.