Freshwater

1
Freshwater
2
Water Resources

• List of supplies for today
• Vocabulary from last night
• Notes pages for all group members
• 3-4 markers
• Big sheet of paper

3

Unconfined Aquifer Recharge Area
Evaporation and transpiration
Evaporation
Precipitation
Confined Recharge Area
Runoff
Flowing artesian well
Recharge Unconfined Aquifer
Stream Well requiring a pump
Water table
Infiltration
Lake
Infiltration
Unconfined aquifer
Less permeable material such as clay
Confined aquifer
Confining impermeable rock layer
Fig. 14-3, p. 308
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On your big paper

• Collaborate together and put your words into 4-5
  different categories according to their likes and
  differences. (NO my vocab, bobs vocab etc.)

5

• Put stars by surface water sources
• Square your ground water sources
• Circle uses of water
• Underline ways we control water

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Surface water

• Flood plains
• Riparian zone
• Lakes (oligotrophic, Mesotrophic, Eutrophic)
• Rivers
• Ponds
• Wetlands

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Ground water

• Aquifers (Confined and Unconfined)
• Water table
• Springs
• Artesian Wells

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Uses

• Furrow irrigation
• Flood irrigation
• Spray irrigation
• Drip Irrigation

9
Controlling water

• Levees
• Dikes
• Dams

10
Sustainability (if you have them)

• Fish Ladders
• Desalinization
• Hydroponic agriculture

11
On your notes

• List and define the works for ground water and
  surface water in your spiral.
• Try to see if you can label the diagram

12
You should be able to do (s 1,4,5,6,7,)

• 1. Aquifer
• 2.confining zone
• 3. Unsaturated zone
• 4. water table
• 5. confined aquifer
• 6. unconfined aquifer
• 7. artesian wells
• 8. water table well
• 9. flowing artesian well

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A. Types of Water

• Surface water

• Ground Water

• Lakes, streams, rivers

• Absorbed in to the ground after a rain.
• More than 50 percent of the people in the United
  States.
• The largest use of ground water is to irrigate
  crops.
• We get ground water out of the ground by wells

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C. Surface FRESHWATER LIFE ZONES

1. Standing (lentic) water such as lakes, ponds, and
   inland wetlands.
2. Flowing (lotic) systems such as streams and
   rivers.

Figure 6-14
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B. Ground Water

• Ground water is the water that fills the empty
  spaces and cracks.
• The top of the water in the soil, sand, or rocks
  is called the water table
• Water seeping down from the land surface adds to
  the ground water and is called recharge water.
• Aquifer is the name given to underground soil or
  rock through which ground water can easily move
• Some wells, called artesian wells, do not need a
  pump.
• These wells are drilled into an artesian aquifer,
  which is sandwiched between two impermeable
  layers.

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C. Surface FRESHWATER LIFE ZONES

1. Standing (lentic) water such as lakes, ponds, and
   inland wetlands. ?
2. Flowing (lotic) systems such as streams and
   rivers. ()

Figure 6-14
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D. Flowing Water Ecosystems

• Because of different environmental conditions in
  each zone, a river is a system of different
  ecosystems.

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Natural Capital
1. Ecological Services of Rivers

1. Deliver nutrients to sea to help sustain coastal
   fisheries
2. Deposit silt that maintains deltas
3. Purify water
4. Renew and renourish wetlands
5. Provide habitats for wildlife

Fig. 12-11, p. 267
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Freshwater Streams and RiversFrom the Mountains
to the Oceans

• Water flowing from mountains to the sea creates
  different aquatic conditions and habitats.

Figure 6-17
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1. Headwater Stream Characteristics

• A narrow zone of cold, clear water that rushes
  over waterfalls and rapids. Large amounts of
  oxygen are present. Fish are also present. Ex.
  trout.

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2. Downstream Characteristics

• Slower-moving water, less oxygen, warmer
  temperatures, and lots of algae and
  cyanobacteria.

22
Standing Water Ecosystems

• Lakes, ponds, etc.

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Life in Layers

• Life in most aquatic systems is found in surface,
  middle, and bottom layers.
• 1. Temperature, access to sunlight for
  photosynthesis, dissolved oxygen content,
  nutrient availability changes with depth.
• 2. Euphotic zone (upper layer in deep water
  habitats) sunlight can penetrate.

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Lakes Water-Filled Depressions

• Lakes are large natural bodies of standing
  freshwater formed from precipitation, runoff, and
  groundwater seepage consisting of
• 3. 4 zones
• Littoral zone (near shore, shallow, with rooted
  plants).
• Limnetic zone (open, offshore area, sunlit).
• Profundal zone (deep, open water, too dark for
  photosynthesis).
• Benthic zone (bottom of lake, nourished by dead
  matter).

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Littoral Zone

• A shallow area near the shore, to the depth at
  which rooted plants stop growing. Ex. frogs,
  snails, insects, fish, cattails, and water lilies.

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Limnetic Zone

• Open, sunlit water that extends to the depth
  penetrated by sunlight.

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Profundal Zone

• Deep, open water where it is too dark for
  photosynthesis.

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5. Thermal Stratification
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Lakes Water-Filled Depressions
Figure 6-15
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Definition

• The temperature difference in deep lakes where
  there are warm summers and cold winters.

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Lakes Water-Filled Depressions

• During summer and winter in deep temperate zone
  lakes the become stratified into temperature
  layers and will overturn.
• This equalizes the temperature at all depths.
• Oxygen is brought from the surface to the lake
  bottom and nutrients from the bottom are brought
  to the top.

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Causes

• During the summer, lakes become stratified into
  different temperature layers that resist mixing
  because summer sunlight warms surface waters,
  making them less dense.

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Thermocline

• The middle layer that acts as a barrier to the
  transfer of nutrients and dissolved oxygen.

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Fall Turnover

• As the temperatures begin to drop, the surface
  layer becomes more dense, and it sinks to the
  bottom. This mixing brings nutrients from the
  bottom up to the surface and sends oxygen to the
  bottom.

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Spring Turnover

• As top water warms and ice melts, it sinks
  through and below the cooler, less dense water,
  sending oxygen down and nutrients up.

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Types of Lakes

• Plant nutrients from a lakes environment affect
  the types and numbers of organisms it can
  support.
• Oligotrophic (poorly nourished) lake Usually
  newly formed lake with small supply of plant
  nutrient input.
• Eutrophic (well nourished) lake Over time,
  sediment, organic material, and inorganic
  nutrients wash into lakes causing excessive plant
  growth.

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Types of Lakes Oligotrophic
Sunlight
Narrow littoral zone
Little shore vegetation
Low concentration of nutrients and plankton
Sparse fish population
Limnetic zone
Sleepily sloping shorelines
Profundal zone
Sand, gravel, rock bottom
Oligotrophic lake
Fig. 7-17a, p. 139
38
Types of Lakes Eutrophic
Sunlight
Wide littoral zone
Much shore vegetation
High concentration of nutrients and plankton
Dense fish population
Limnetic zone
Gently sloping shorelines
Profundal zone
Silt, sand, clay bottom
Fig. 7-17b, p. 139
Eutrophic lake
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How we use our water and the problems we create?
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Problems
41
Too Much Water

• Problems include flooding, pollution of water
  supply, and sewage seeping into the ground.

42
TOO MUCH WATER

• Heavy rainfall, rapid snowmelt, removal of
  vegetation, and destruction of wetlands cause
  flooding.
• Floodplains, which usually include highly
  productive wetlands, help provide natural flood
  and erosion control, maintain high water quality,
  and recharge groundwater.
• To minimize floods, rivers have been narrowed
  with levees and walls, and dammed to store water.

43
TOO MUCH WATER

• Comparison of St. Louis, Missouri under normal
  conditions (1988) and after severe flooding
  (1993).

Figure 14-22
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TOO MUCH WATER

• Human activities have contributed to flood deaths
  and damages.

Figure 14-23
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Forested Hillside
Oxygen released by vegetation
Diverse ecological habitat
Evapotranspiration
Trees reduce soil erosion from heavy rain and wind
Agricultural land
Steady river flow
Leaf litter improves soil fertility
Tree roots stabilize soil and aid water flow
Vegetation releases water slowly and reduces
flooding
Fig. 14-23a, p. 330
46

After Deforestation
Tree plantation
Evapotranspiration decreases
Roads destabilize hillsides
Ranching accelerates soil erosion by water and
wind
Winds remove fragile topsoil
Gullies and landslides
Agricultural land is flooded and silted up
Heavy rain leaches nutrients from soil and erodes
topsoil
Rapid runoff causes flooding
Silt from erosion blocks rivers and reservoirs
and causes flooding downstream
Fig. 14-23b, p. 330
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Too Little Water
48
Examples

• Examples include drought and expanding deserts.

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Overdrawing Surface Water

• Lake levels drop, recreation use drops, fisheries
  drop, and salinization occurs. Ex. Soviet Union
  (Aral Sea) the inland sea drained the river that
  fed into it. Now its a huge disaster (read pg.
  322 in text).

1997
1964
50
Case Study The Aral Sea Disaster

• Diverting water from the Aral Sea and its two
  feeder rivers mostly for irrigation has created a
  major ecological, economic, and health disaster.
• About 85 of the wetlands have been eliminated
  and roughly 50 of the local bird and mammal
  species have disappeared.
• Since 1961, the seas salinity has tripled and
  the water has dropped by 22 meters most likely
  causing 20 of the 24 native fish species to go
  extinct.

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Aquifer Depletion

• This harms endangered species, and salt water can
  seep in.

52
Salinization of Irrigated Soil

• Water is poured onto soil and evaporates. Over
  time, as this is repeated, nothing will grow
  there anymore.

53
U.S. Water Problems
54
Surface Water Problems

• The polluted Mississippi River (non-source point
  pollution) has too much phosphorus.
• In the Eerie Canal, which connects the ocean to
  the Great Lakes, lampreys came in and depleted
  the fish. The zebra mollusk is also a problem in
  the Great Lakes.

55
Effects of Plant Nutrients on LakesToo Much of
a Good Thing

• Plant nutrients from a lakes environment affect
  the types and numbers of organisms it can support.

Figure 6-16
56
Effects of Plant Nutrients on LakesToo Much of
a Good Thing

• Cultural eutrophication
• Human inputs of nutrients from the atmosphere and
  urban and agricultural areas can accelerate the
  eutrophication process.

57
Mono Lake

• (like the Dead Sea) This has a huge salt
  concentration due to mans draining.

58
Colorado River Basin

• These are dams reservoirs that feed from the
  Colorado River all the way to San Diego, LA, Palm
  Springs, Phoenix Mexico. So far has worked
  because they havent withdrawn their full
  allocations. See pg306.

59
The Colorado River Basin

• The area drained by this basin is equal to more
  than one-twelfth of the land area of the lower 48
  states.

Figure 14-14
60

IDAHO
WYOMING
Dam
Aqueduct or canal
Salt Lake City
Upper Basin
Denver
Grand Junction
Lower Basin
UPPER BASIN
UTAH
Colorado River
NEVADA
Lake Powell
COLORADO
Grand Canyon
Glen Canyon Dam
Las Vegas
NEW MEXICO
Boulder City
CALIFORNIA
Los Angeles
ARIZONA
Albuquerque
LOWER BASIN
Palm Springs
0
100 mi.
Phoenix
San Diego
Yuma
0
150 km
Tucson
Mexicali
All-American Canal
MEXICO
Gulf of California
Fig. 14-14, p. 318
61
Case Study The Colorado Basin an Overtapped
Resource

• The Colorado River has so many dams and
  withdrawals that it often does not reach the
  ocean.
• 14 major dams and reservoirs, and canals.
• Water is mostly used in desert area of the U.S.
• Provides electricity from hydroelectric plants
  for 30 million people (1/10th of the U.S.
  population).

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Case Study The Colorado Basin an Overtapped
Resource

• Lake Powell, is the second largest reservoir in
  the U.S.
• It hosts one of the hydroelectric plants located
  on the Colorado River.

Figure 14-15
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Groundwater Problems

• These include pollution, salt, and draining too
  much.

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Other Effects of Groundwater Overpumping

• Sinkholes form when the roof of an underground
  cavern collapses after being drained of
  groundwater.

Figure 14-10
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Groundwater Depletion A Growing Problem

• Areas of greatest aquifer depletion from
  groundwater overdraft in the continental U.S.

• The Ogallala, the worlds largest aquifer, is
  most of the red area in the center (Midwest).

Figure 14-8
66
Ogallala Aquifer

• This is the worlds largest known aquifer, and
  fuels agricultural regions in the U.S. It
  extends from South Dakota to Texas. Its
  essentially a non-renewable aquifer from the last
  ice age with an extremely slow recharge rate. In
  some cases, water is pumped out 8 to 10 times
  faster than it is renewed. Northern states will
  still have ample supplies, but for the south its
  getting thinner. It is estimated that ¼ of the
  aquifer will be depleted by 2020.

67
Global Water Problems
68
Impacts of Human Activities on Freshwater Systems

• Dams, cities, farmlands, and filled-in wetlands
  alter and degrade freshwater habitats.
• Dams, diversions and canals have fragmented about
  40 of the worlds 237 large rivers.
• Flood control levees and dikes alter and destroy
  aquatic habitats.
• Cities and farmlands add pollutants and excess
  plant nutrients to streams and rivers.
• Many inland wetlands have been drained or filled
  for agriculture or (sub)urban development.

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Core Case Study A Biological Roller Coaster Ride
in Lake Victoria

• Lake Victoria has lost their endemic fish species
  to large introduced predatory fish.

Figure 12-1
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Core Case Study A Biological Roller Coaster Ride
in Lake Victoria

• Reasons for Lake Victorias loss of biodiversity
• Introduction of Nile perch.
• Lake experienced algal blooms from nutrient
  runoff.
• Invasion of water hyacinth has blocked sunlight
  and deprived oxygen.
• Nile perch is in decline because it has eaten its
  own food supply.

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Stable Runoff

• As water runs off from rain, its supposed to get
  into rivers, and finally off to the sea. But
  when we dam rivers, less goes to the ocean,
  meaning the brackish water (where the river hits
  the ocean) becomes more salty. This is the
  breeding ground for many fish and invertebrates.
  This harms the ecology of the area.

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Population Growth

• Problems include over-drawing fresh water,
  pollution, and over-building so that water cant
  seep into the ground.

73
Sharing Water Resources

• There are water wars out west. California bought
  the water from the Colorado River, but Arizona
  wants it. Who owns it? The same thing is
  happening in Texas. More water rights are sold
  than the actual amount of water. How do you
  share water? This is a problem all over the
  world.

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Water Management
75
Dams and Reservoirs

• Description A dammed stream that can capture
  store water from rain melted snow.
• Benefits Hydroelectric power provides water
  to towns recreation controls floods downstream
• Problems Reduces downstream flow prevents
  water from reaching the sea (Colorado River)
  devastates fish life reduces biodiversity.

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USING DAMS AND RESERVOIRS TO SUPPLY MORE WATER

• Large dams and reservoirs can produce cheap
  electricity, reduce downstream flooding, and
  provide year-round water for irrigating cropland,
  but they also displace people and disrupt aquatic
  systems.

77

Provides water for year-round irrigation of
cropland
Flooded land destroys forests or cropland and
displaces people
Large losses of water through evaporation
Provides water for drinking
Downstream cropland and estuaries are deprived of
nutrient-rich silt
Reservoir is useful for recreation and fishing
Risk of failure and devastating downstream
flooding
Can produce cheap electricity (hydropower)
Downstream flooding is reduced
Migration and spawning of some fish are disrupted
Fig. 14-13a, p. 317
78

Powerlines
Reservoir
Dam
Powerhouse
Intake
Turbine
Fig. 14-13b, p. 317
79
Case Study Chinas Three Gorges Dam

• There is a debate over whether the advantages of
  the worlds largest dam and reservoir will
  outweigh its disadvantages.
• The dam will be 2 kilometers long.
• The electric output will be that of 18 large
  coal-burning or nuclear power plants.
• It will facilitate ship travel reducing
  transportation costs.
• Dam will displace 1.2 million people.
• Dam is built over seismatic fault and already has
  small cracks.

80
Dam Removal

• Some dams are being removed for ecological
  reasons and because they have outlived their
  usefulness.
• In 1998 the U.S. Army Corps of Engineers
  announced that it would no longer build large
  dams and diversion projects in the U.S.
• The Federal Energy Regulatory Commission has
  approved the removal of nearly 500 dams.
• Removing dams can reestablish ecosystems, but can
  also re-release toxicants into the environment.

81
Water Diversion

• Description Damming a river to control where
  the water flows
• Benefits Keeps water where we want it- cities!
• Problems Drains wetlands, destroys land

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Desalinization

• Description Removing salt from salt water
• Benefits Freshwater
• Problems Uses lots of energy costs 3-5Xs more
  money what do we do with the salt?

83
DESALTING SEAWATER, SEEDING CLOUDS, AND TOWING
ICEBERGS AND GIANT BAGGIES

• Removing salt from seawater by current methods is
  expensive and produces large amounts of salty
  wastewater that must be disposed of safely.
• Distillation heating saltwater until it
  evaporates, leaves behind water in solid form.
• Reverse osmosis uses high pressure to force
  saltwater through a membrane filter.

84
DESALTING SEAWATER, SEEDING CLOUDS, AND TOWING
ICEBERGS AND GIANT BAGGIES

• Seeding clouds with tiny particles of chemicals
  to increase rainfall towing icebergs or huge bags
  filled with freshwater to dry coastal areas have
  all been proposed but are unlikely to provide
  significant amounts of freshwater.

85
Harvesting Icebergs

• Description Towing massive icebergs to arid
  coastal areas (S. California Saudi Arabia)
• Benefits freshwater
• Problems Technology not available costs too
  high raise temperatures around the earth.

86
INCREASING WATER SUPPLIES BY WASTING LESS WATER

• Sixty percent of the worlds irrigation water is
  currently wasted, but improved irrigation
  techniques could cut this waste to 5-20.
• Center-pivot, low pressure sprinklers sprays
  water directly onto crop.
• It allows 80 of water to reach crop.
• Has reduced depletion of Ogallala aquifer in
  Texas High Plains by 30.

87

Drip irrigation
(efficiency 9095)
Gravity flow
(efficiency 60 and 80 with surge valves)
Center pivot
(efficiency 8095)
Water usually pumped from underground and sprayed
from mobile boom with sprinklers.
Above- or below-ground pipes or tubes deliver
water to individual plant roots.
Water usually comes from an aqueduct system or a
nearby river.
Fig. 14-18, p. 325
88
Conservation

• Description Saving the water we have
• Methods recycling conserving at home
  xeriscaping fix leaks
• Benefits Saves money Saves Wildlife
• Problems bothersome to people lack of caring
  laziness