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Chapter 11: Water
(Notes)
sec1: Water Resources
- humans can survive for more than a month without food, can live for few days without water
1. fresh water - water that people can drink)
2. salt water - water in oceans - most human use fresh water
- humans can survive for more than a month without food, can live for few days without water
1. fresh water - water that people can drink)
2. salt water - water in oceans - most human use fresh water
The Water Cycle
- water is renewable resource - circulated in water cycle
process:
- water molecules travel between Earth's surface & atmosphere
- water evaporates & leaves behind salts
- water vapor (gas) rises into the air
- gas cools & condenses into drops of liquid water - form clouds
- water is renewable resource - circulated in water cycle
process:
- water molecules travel between Earth's surface & atmosphere
- water evaporates & leaves behind salts
- water vapor (gas) rises into the air
- gas cools & condenses into drops of liquid water - form clouds
Global Water
Distribution
- 97% water is salt water in oceans
- fresh water comes from lakes and rivers & narrow zone beneath the Earth's surface
- 97% water is salt water in oceans
- fresh water comes from lakes and rivers & narrow zone beneath the Earth's surface
sec 2: Water Use and
management
- World Health Organization - more than 1 billion people lack access to clean fresh water
- World Health Organization - more than 1 billion people lack access to clean fresh water
Global Water Use
- fresh water used
worldwide is used to irrigate crops
- availability of fresh water, population sizes, and economic conditions affect how people use water
Residential Water Use
- remainder of the water used outside the home for activities
- availability of fresh water, population sizes, and economic conditions affect how people use water
Residential Water Use
- remainder of the water used outside the home for activities
– watering lawns and
washing
cars
(Water Treatment),
arsenic, lead, which are poisonous to humans even in low
concentrations
- also removes pathogen - organism that cause illness or disease
cars
(Water Treatment),
arsenic, lead, which are poisonous to humans even in low
concentrations
- also removes pathogen - organism that cause illness or disease
Industrial Water Use
- needed to manuufacture everyday items
- cool power plants
- needed to manuufacture everyday items
- cool power plants
Agricultural Water
Use
-agriculture evaporates and never reaches plant roots
(Irrigation)
- method of providing plants with water from sources
-agriculture evaporates and never reaches plant roots
(Irrigation)
- method of providing plants with water from sources
Water Management
Projects
- brought water from mountains to the dry areas
- complex
- designed to meet these needs
(Water Diversion Projects)
- Colorado River begins as a glacial stream & quickly grows larger
(Dams and Reservoirs)
- dam - structure built across a river to control river's flow
- reservoir - formed behind the dam
- dams are used to generate electrical energy
- hydroelectric dams use power of flowing water
- brought water from mountains to the dry areas
- complex
- designed to meet these needs
(Water Diversion Projects)
- Colorado River begins as a glacial stream & quickly grows larger
(Dams and Reservoirs)
- dam - structure built across a river to control river's flow
- reservoir - formed behind the dam
- dams are used to generate electrical energy
- hydroelectric dams use power of flowing water
Water Conservation
(Water Conservation in Agriculture)
- water loss comes from evaporation, seepage, runoff
-sometimes managed by computer programs that coordinate watering
- make more water available for agricultural and residential use
(Water Conservation at Home)
- water-saving technology help reduce household water use
- pay residents to install water-saving equipment
(Water Conservation in Agriculture)
- water loss comes from evaporation, seepage, runoff
-sometimes managed by computer programs that coordinate watering
- make more water available for agricultural and residential use
(Water Conservation at Home)
- water-saving technology help reduce household water use
- pay residents to install water-saving equipment
Solutions for the
Future
(Desalination)
- process of removing salt from salt water
(Transporting Water)
- ships travel regularly from mainland towing enormous plastic bags of fresh water
- explore possibility of filling huge bags with water
(Desalination)
- process of removing salt from salt water
(Transporting Water)
- ships travel regularly from mainland towing enormous plastic bags of fresh water
- explore possibility of filling huge bags with water
sec 3: Water
Pollution
- degrade water quality & adversely affect the organisms that depend on the water
- industrialization and rapid human population growth
- degrade water quality & adversely affect the organisms that depend on the water
- industrialization and rapid human population growth
Point-Source
Pollution
- factory, wastewater treatment plant, leaking oil tanker
- pollution discharged from a single source
- can be identified and traced to a source
Nonpoint-Sourc Pollution
- river can be polluted by runoff from any of the land
- 96% of polluted water in US were contaminated by nonpoint sources
- factory, wastewater treatment plant, leaking oil tanker
- pollution discharged from a single source
- can be identified and traced to a source
Nonpoint-Sourc Pollution
- river can be polluted by runoff from any of the land
- 96% of polluted water in US were contaminated by nonpoint sources
Wastewater
- wastewater contains biodegradable material can be broken down by living organisms
- wastewater treatment plants may not remove all the harmful substances in water
- storm-water runoff contains toxic substances
(Sewage sludge)
- When sludge contains
Artificial Eutrophication
- more plants grow, the shallow waters begin to fill in.
Eventually, the body of water becomes a swamp
- more plants grow, the shallow waters begin to fill in.
Eventually, the body of water becomes a swamp
Thermal Polllution
a few degrees, the amount of oxygen the water can hold decreases
significantly
(Groundwater Pollution)
- Pesticides,
herbicides, chemical fertilizers, and petroleum products are common
groundwater pollutants
- most of the
a few degrees, the amount of oxygen the water can hold decreases
significantly
(Groundwater Pollution)
- Pesticides,
herbicides, chemical fertilizers, and petroleum products are common
groundwater pollutants
- most of the
Ocean Pollution
- ships can legally dump
wastewater and garbage overboard in some parts of the ocean
- 85 percent of ocean pollution—including pollutants
such as oil, toxic wastes, and medical wastes - from land
- ships can legally dump
wastewater and garbage overboard in some parts of the ocean
- 85 percent of ocean pollution—including pollutants
such as oil, toxic wastes, and medical wastes - from land
Water Pollution and
Ecosystems
- toxic chemicals spilled directly into a river can kill nearly
all living things for miles downstream
- pollutants accumulate
in the environment because they do not
- toxic chemicals spilled directly into a river can kill nearly
all living things for miles downstream
- pollutants accumulate
in the environment because they do not
Cleaning Up Water
Pollution
- Clean Water Act of 1972 - stated purpose
of the act was to “restore and maintain the chemical, physical,
and biological integrity of the nation’s waters.”
- goal: make all surface water clean enough for fishing and swimming
- Clean Water Act of 1972 - stated purpose
of the act was to “restore and maintain the chemical, physical,
and biological integrity of the nation’s waters.”
- goal: make all surface water clean enough for fishing and swimming
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