Opening Assignment What does the term ecological footprint
mean? Today we will finish our Campaign for Change poster contest
and then start watching the documentary Human Footprinting by
National Geographic.
http://www.snagfilms.com/films/title/human_footprint Tomorrow you
will present your project and then we will finish the
documentary.
Slide 2
Opening Assignment Get your project ready to present.
Slide 3
Opening Assignment Opening Assignment How did watching the
documentary Human Footprinting change how you feel about the way
that you use resources?
Slide 4
Opening Assignment 1. Differentiate between a renewable and
nonrenewable or limited resource. 2. How much of the water on Earth
do you think is considered to be fresh water? 3. Of that percentage
of fresh water how much do you think is found in icebergs and
glaciers?
Slide 5
By Mrs. Shaw
Slide 6
Unit 3: Part 1 Water Resources Learning Goals for Part 1:
Students will be able to Differentiate between a renewable and
nonrenewable resource. Describe how fresh water is stored on Earth
Explain how humans impact the availability of fresh water. Design
and create a system to filter water.
Slide 7
What are natural resources? Natural resources are materials and
energy sources found in nature. Many of them are limited.
Slide 8
Renewable vs. Nonrenewable Renewable: a resource that is
replenished or renewed over short periods of time. Examples:
sunlight, wind energy, wave energy, geothermal energy,
Non-renewable: a resource that is formed much more slowly than it
is used. Examples: crude oil, natural gas, coal, copper, aluminum
and other metals.
Slide 9
Renewable resources at risk! Some renewable resources are at
risk of being depleted because our human population and resource
consumption over the past several hundred years has increased
dramatically. These resources that are at risk of being converted
to nonrenewable are fresh water, forest products, agricultural
products, and soil.
Slide 10
What is Sustainability? Sustainability is the process of using
these at risk resources at a rate that allows them time to renew.
Sustainability ensures that these resources will be available for
future generations.
https://www.youtube.com/watch?v=B5NiTN0chj0
Slide 11
How to increase our sustainability factor. Care instructions
for a sustainable planet 1. Reduce our dependence on fossil fuels
and heavy metals. 2. Reduce our dependence on synthetic chemicals.
3. Reduce our destruction of nature 4. Ensure we are not limiting
other people globally from meeting their needs.
Slide 12
The Water Resources of Earth Over 70% of our Earth's surface is
covered by water ( we should really call our planet "Ocean" instead
of "Earth"). Although water is seemingly abundant, the real issue
is the amount of fresh water available. 97.5% of all water on Earth
is salt water, leaving only 2.5% as fresh water Nearly 70% of that
fresh water is frozen in the icecaps of Antarctica and Greenland;
most of the remainder is present as soil moisture, or lies in deep
underground aquifers as groundwater not accessible to human use.
< 1% of the world's fresh water (~0.007% of all water on earth)
is accessible for direct human uses. This is the water found in
lakes, rivers, reservoirs and those underground sources that are
shallow enough to be tapped at an affordable cost. Only this amount
is regularly renewed by rain and snowfall, and is therefore
available on a sustainable basis.
Slide 13
Opening Assignment Look at the Water Stress map above. Infer
why you think these specific areas are stressed with water
resources (limited)
Slide 14
Water Availability and Stress Water is not evenly distributed
throughout various biomes. When people choose to live in locations
where water is limited or populations are high, it puts more of a
strain on our limited water resources.
Slide 15
Assignment Finish the Environmental Science Textbook questions
that you started yesterday. If you complete these, please turn them
in to be graded. These are due tomorrow.
Slide 16
Opening Assignment What are the two places that water is stored
on Earth? Explain how much of the water on Earth is available for
human consumption.
Slide 17
Chapter 20 Section 1 Review Uses for Water The average person
uses 300L of water daily. They use it primarily for personal
hygiene and home cleaning. Household activities that use the most
water are washing clothes, washing dishes, bathing, and
showering.
Slide 18
Residential and Industrial Water Use Residentially, people use
the most water gardening, landscaping, washing vehicles, and
filling up pools. Most of our fresh water available is used for
agriculture. (47%). In industry, water is used to transport and
dispose of wastes, as a power source (hydropower), and as a
coolant.
Slide 19
Effects of water on Ecosystems Human needs for water alter or
destroy the habitats of other living things. The building of dams,
draining of swamps, changing of stream courses, or removal of water
from natural sources can all adversely affect wildlife.
Slide 20
On Earth, water is classified and stored in two areas, surface
water and groundwater. Surface water is water that is stored above
grounds in lakes, rivers, streams, and ponds. Sources of surface
water are rainfall and the water from melting snow, glaciers, and
ice sheets. When this water travels down a slope of land it is
called runoff. Chapter 20 Section 2 Review Water Resources
Slide 21
Surface Water from the ground Surface water can also come from
underground aquifers. If a stream channel intersects the aquifer,
the water in the aquifer can flow into the stream channel. Water in
aquifers can also cross geological faults and flow to the surface
as springs. Water in the Colorado River comes from the melting of
ice on the Rocky Mountains. It also supplies water to the Rio
Grande which brings water to Texas and Mexico.
Slide 22
Groundwater The water that does not flow as runoff seeps into
the spaces between soil particles and into the porous layer of
bedrock below. This water is called groundwater. Over long periods
of time this groundwater saturates the bedrock. The top layer of
saturated rocks is called the water table.
Slide 23
The zone of aeration is where water enters an aquifer. The zone
of saturation is the area of saturated rocks below the water table.
The zone of discharge is where water from an aquifer leaves and
becomes part of the surface water in a stream, or pond.
Slide 24
Water Resource Problems When a body of water is drained faster
than it is filled, the effect is called overdraft. If overdraft
occurs, salt water can intrude into the freshwater aquifer, making
the water unpotable.
Slide 25
Countries or continents with unsafe water include South
America, Mexico, China, and parts of Africa Chapter 20 Section 3
Review Water Treatment Percentage of population with access to safe
water by country
Slide 26
Removing Salts Some organisms have adaptations that allow them
to survive in a high salinity environment like ocean water.
Penguins are one of these organisms. Penguins have special glands
that remove salts from their bloodstream. The supraorbital gland is
a type of lateral nasal gland found in some species of marine
birds, particularly penguins, which removes sodium chloride from
the bloodstream. The gland's function is similar to that of the
kidneys, though it is much more efficient at removing salt,
allowing Penguins to survive without access to fresh water.
Contrary to popular belief, the gland does not directly convert
saltwater to freshwater
Slide 27
Desalination The process by which salts are removed from water
is called desalination. The three most common methods of
desalination are Distillation Reverse osmosis Freezing
Slide 28
Distillation In distillation, salt water is heated to boiling.
Water is evaporated but the salt remains. The water vapor is cooled
and liquid fresh water is collected.
Slide 29
Reverse Osmosis In reverse osmosis, salt water is forced
through a strainer that traps the salt and lets the fresh water
pass. The strainer is made of tiny pores that are large enough for
water to pass but too small for salt.
Slide 30
Freezing In the freezing method, salt water is frozen. As it
freezes it separates, forming ice and a brine slush. The ice is
free of almost all salts and can be melted to obtain fresh
water.
Slide 31
Water Purification The goal of water purification is to remove
harmful chemicals and microorganisms that make water undrinkable.
Water purification involves several processes; sedimentation,
filtration, aeration, and sterilization.
Slide 32
Sedimentation and Filtration The first part of water
purification uses screens to remove the large items in the water.
The water is then placed in a settling tank where the particles in
the water are given time and allowed to settle at the bottom. Water
drained from the sedimentation tank is then sent through 1 meter of
fine sand to filter out many of the particles that were not removed
through sedimentation.
Slide 33
Aeration and Sterilization After the filtration it is time to
treat the water for taste, odor, and bacteria using aeration and
sterilization. Aeration involves spraying water into the air which
allows bacteria that help purify it to enter along with oxygen
which is a powerful purifying agent. Sterilization includes using
heat or chemicals to kill any remaining bacteria or
microorganisms.
Slide 34
Chemicals for Sterilization The two most common chemical used
for sterilization include chlorine and ozone. Ozone is a better
purifying agent but it is more expensive and difficult to use so
chlorine is used more commonly.
Slide 35
Videos Water Purification Process
https://www.youtube.com/watch?v=tuYB8nMFxQA Desalination
https://www.youtube.com/watch?v=2XMRlFMJB-g
