What is weathering?
What is erosion?
What is deposition?
Write the answers on
the back of the notes
page
What is groundwater?
– Water that is found underground in the cracks
and spaces in soil and rock.
– Water that is stored underground and is used
for human use is called an Aquifer.
Why is groundwater important?
• IT IS THE MAJOR SOURCE FOR
WATER!
– One third of the earth’s freshwater is located
in the form of ice.
– Rivers and lake water is easily
contaminated, as well as being over used.
– Nationally, half of the population of the USA
drinks groundwater. Most crops are irrigated
with ground water.
Evaporation and transpiration
Evaporation
Stream
Infiltration
Water table Infiltration
Unconfined aquifer
Confined aquifer
Lake
Well requiring a pump
Flowing
artesian well
Runoff
Precipitation
Confined
Recharge Area
Aquifer
Less permeable material
such as clay Confirming permeable rock layer
Ground Water
Fig. 15-3 p. 308
What is a watershed? A watershed is an area of land from which
all runoff drains, or 'sheds' to the same
river, lake, or other body of water.
Everyone lives in a watershed
Your own backyard is
part of a watershed.
You’re already in one! You don’t need to visit the Grand Canyon to see a watershed.
A Nested System Watersheds are also like Russian Matryoshka or nesting dolls. Larger watersheds contain smaller watersheds, which contain even smaller ones.
Weather & Watersheds: Rain
How do we pollute/contaminate
our watersheds?
1.Garbage/waste/dumping
2.Surface water run off
Texas Groundwater and Aquifers
• Human effects on groundwater!
– Pollutants on the land surface
– Buried items such as gasoline tanks, septic
systems (toilet, bath and sink water) and
landfills.
Supply of Water Resources
Fig. 15-2 p. 307
Freshwater Readily accessible freshwater
Biota
0.0001%
Rivers
0.0001%
Atmospheric
water vapor
0.0001%
Lakes
0.0007%
Soil
moisture
0.0005%
Groundwater
0.592%
Ice caps
and glaciers
0.592%
0.014%
Human water needs
• A person needs about 1/2 gallon water/day for hydration
• In the US each person uses about 188 gallons/day
• An additional 657 gallons/person/day are used for irrigation, industrial use.
• If the world’s water supply were 100 liters, the usable supply would be about 0.5 tsp
• US has highest per capita water withdrawal, followed by Canada, Australia, Russia, Japan
How water is used
• In the western US, irrigation makes up
85% of all water use
--50% to grow food for livestock
-- 35% to grow crops
Not sustainable…cost of water is heavily
subsidized by the federal government
Effects of Pollution on the
Environment?
• Short Term • Contaminated water
• Kills plants and animals
• Destroys the natural
beauty of a habitat
• Long Term • Health problems
• Loss of drinking and
irrigation water
• Birth defects
• Loss of different species
(plant or animal)
Sources of Pollution Precipitation runoff from farms, lawns, and paved surfaces is
the leading source of water pollution in America today.
NONPOINT SOURCES
Urban streets
Suburban development
Wastewater treatment plant
Rural homes
Cropland
Factory
Animal feedlot
POINT SOURCES
Fig. 22-4 p. 494
Aquifers
• An aquifer is a body of highly permeable
rock that can store water and yield
sufficient quantities to supply wells.
• Bodies of gravel and sand generally are
good aquifers, because they tend to be
highly permeable and often have large
dimensions.