Chapter 10 Freshwater Resources and Water Pollution

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Chapter 10 Freshwater Resources and Water
Pollution
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The Importance of Water

• All living things need water
• You are about 70 water by weight
• What do we use water for?

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Water on Earth

• About 97 Earths water is salty
• Fresh water is distributed unevenly
• 2025 1/3 human population will live in areas
  lacking fresh water
• What can be done about this?
• Water is continuously cycling through the
  environment

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Hydrologic Cycle

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Groundwater

• Supply of fresh water found under Earths surface
• Stored in underground aquifers
• Discharged into rivers,
  springs, etc
• Usually considered nonrenewableWhy?

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Water Resource Problems

• Too much water
• Too little water
• Poor-quality water

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Flooding

• Rivers discharge cant be contained
• Floods more disastrous today why?
• What can be done?

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Too Little Water

• Arid semiarid lands
• Irrigation
• Needed to produce food
• Greatest use of water
  (71)

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Overdrawing Surface Waters

• Damaging to ecosystems
• Wetlands dry up
• Estuaries become too salty
• Why are we removing so much water?
• Where is this
  happening?

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Water Conservation Municipal
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Water Pollution

• Physical or chemical change in water that
  adversely affects the health of humans or other
  organisms
• Global problem
• Eight different
  types

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Types of Water Pollution
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Effect of Sewage on BOD
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Municipal Sewage Treatment

• Arcata, California
• Wetlands aid in treatment
• Marshes absorb contaminants
• Provides wildlife habitat

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Preventing Water Pollution At Home
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Water Pollution In Developing Countries

• 1.4 billion people lack safe drinking water
• 2.9 billion people lack adequate sanitation
• Water for drinking
  polluted by human
  wastes, chemicals,
  human remains

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Case Study The Great Lakes

• Provide drinking water for 38 million people
• Were highly polluted
• Toxic chemicals
• Eutrophication
• Fish kills common

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Case Study The Great Lakes

• Canada U.S. cooperate today
• 20 billion spent on cleanup since 1972
• Many improvements
• DDT in breast milk declined
• PCBs in trout declined
• Some animal species rebounding

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Case Study The Great Lakes

• Todays problems
• Many invasive species
• Too much shoreline development
• Some persistent toxins remain
• Fish may contain high levels of toxins

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Chapter 11 The Ocean and Fisheries
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Major Ocean Life Zones

• Intertidal zone
• Benthic environment
• Pelagic environment
• Ocean water
• Neritic province
• Oceanic province

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Fishing Facts

• 80 U.S. fish stocks in trouble
• 30 fish species overfished worldwide
• Why do we take so many fish?

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Modern Fishing Methods
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Ocean diseases

• Read the Harvell et al. paper The rising tide of
  ocean diseases
• Choose one marine disease discussed and use
  information from the appear, library resources,
  the internet, and textbooks to briefly explain
  the following
• A. symptoms of the disease
• B. pathogens causing the illness, including how
  they are transmitted
• C. anthropogenic factors influencing the disease
• D. known or potential treatments
• E. three ways this marine disease is similar to
  human disease casued by a similar pathogen
• Turn in Thursday at beginning of class. Keep a
  copy for class discussion.