ES 6.4 LESSON Freshwater Ecosystems

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Environmental Science, 1e
SUSTAINING YOUR WORLD
G. TYLER MILLER | SCOTT E. SPOOLMAN

6

Ecosystems and Climate

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• Surface water: fresh water that flows or is stored in bodies

of water on Earth’s surface

• Freshwater life zones include standing water (lakes, ponds,

inland wetlands) and flowing water (streams, rivers).

– Runoff: surface water that flows into lakes, ponds, wetlands

– Watershed: land area that delivers runoff, sediments, and

dissolved substances to freshwater systems

6.4 What Are the Major Types of Freshwater
Ecosystems?

Categorize

Options (5)

lakes

ponds

wetlands (inland)

streams

rivers

Organize these options into the right categories

Standing Water

Flowing Water

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Freshwater Systems Provide Ecosystem Services

• Ecosystem Services

– Climate moderation

– Nutrient cycling

– Waste treatment

– Flood control

– Groundwater recharge

– Habitat

– Genetic resources and biodiversity

– Scientific information

Multiple Select

Which of these are ecosystem services provided by freshwater systems?

• Climate moderation

• Nutrient Cycling

• Waste treatment

• Flood Control

• Hydroelectricity

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• Economic Services

– Food

– Drinking water

– Irrigation water

– Hydroelectricity

– Transportation corridors

– Recreation

Freshwater Systems Provide Economic Services

Multiple Select

Which of these are ECONOMIC services provided by freshwater systems?

• Drinking Water

• Transportation Corridors

• Recreation

• Nutrient Cycling

• Hydroelectricity

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• Lakes

– Natural depressions that contain standing water; fed by

precipitation, runoff, streams, rivers, groundwater seepage

• Deep lakes normally consist of life zones defined by depth and distance

from shore

• Oligotrophic lakes: typically deep and steep sided with a small nutrient

supply

• Eutrophic lakes: typically shallow and murky with a large supply of
nutrients

Lake Systems

Match

Match the following

• life zones defined by depth and distance from shore

• Deep/Steep

  low nutrient supply

• Shallow/Murky

  large supply of nutrients

Deep Lakes

Oligotrophic Lakes

Eutrophic Lakes

• Deep Lakes

• Oligotrophic Lakes

• Eutrophic Lakes

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Lake Zones

Match

Match the following

• shallow water near the shore

  (area between dry land and open water)

• open water

  too deep for plants to root

  light penetrates top layers, but doesn't go all the way to the bottom

• Deep water with little to no light.

  Decomposition DOES NOT occur here

• lowest level of a body of water

  sediment and decomposition are here

Littoral Zone

Limnetic Zone

Profundal Zone

Benthic Zone

• Littoral Zone

• Limnetic Zone

• Profundal Zone

• Benthic Zone

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• Streams join to form rivers, which carry large volumes of

water.

• Rivers flow through source, transition, and floodplain zones.
• Streams that flow downhill shape the land.

– Cutting valleys, creating sand, gravel, and soil

– Delta forms at the mouth of a river, where sediment from

upstream is deposited

• Often contain estuaries and wetlands

Streams and Rivers

Match

Match the following

• join to form rivers

• deposits of sediment at the mouth of a river

• large volumes of flowing water

• shape the land

  create sand, gravel and soil

streams

delta

rivers

downhill streams

• streams

• delta

• rivers

• downhill streams

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Flow of Rivers

Reorder

Reorder the following zones.

• Source Zone

• Transition Zone

• Floodplain Zone

1

2

3

• 1
• 2
• 3

Reorder

Reorder the following, starting with the source of a river.

• Rain

• Waterfall

• Floodplain

• Delta

• Ocean

1

2

3

4

5

• 1
• 2
• 3
• 4
• 5

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• Covered with fresh water all or part of time

– Floodplains, swamps, small ponds, prairie potholes

• Provide ecosystem and economic services

– Filter/degrade waste and pollution

– Limit flooding and erosion

– Sustain stream flow during droughts

– Help to recharge ground water aquifers

– Maintain biodiversity

– Provide food and recreation for humans

Freshwater Inland Wetlands

Multiple Select

Select the examples of Freshwater Inland Wetlands

• floodplains

• swamps

• estuaries

• small ponds

• prairie potholes

Multiple Select

Select the examples of services provided by Freshwater Inland Wetlands

• filter waste

• recharge groundwater

• stabilize water salinity

• food

• recreation

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• Water flow is restricted by dams and canals.
• Water flow is disrupted by flood control levees and dikes.
• Agricultural and urban pollutants are added to
freshwater systems

• Wetlands have been drained or filled in to grow crops or

for construction of buildings.

Human Impacts on Freshwater Systems

Multiple Select

What are some human impacts on freshwater systems?

• restricting water flow with dams

• disrupting water flow with flood control measures

• pollution from agriculture

• clearing wetlands for crops or construction

• overfishing of oceans