Performance Benchmark E.12.C.4
Students know processes of obtaining, using, and recycling of renewable and non-renewable
resources. E/S
By one definition, natural resources are “a material source of wealth, such as timber, fresh water,
or a mineral deposit, that occurs in a natural state and has economic value.” However this
definition has a distinctly “human” spin to it. Some natural resources may not have an
immediate economic value to humans, but may be of great value to other organisms that are
dependant upon them for their survival. All too often when the concept of natural resources is
presented to students, too much emphasis is placed on the immediate economic value to humans
and any material that lacks that value is not presented as a “natural resource”. Examples of this
can be seen throughout human history as technologies and societies have changed, materials that
have had little or no economic value suddenly become of great importance, and the importance
of other resources drops off. For example, wood was the main energy source prior to the
industrial revolution. With the advent of the steam engine and more efficient methods of
extracting coal from the ground, wood became a less important energy source in the “developed”
nations that had access to coal. With this said, wood is still the main source of biomass fuel and
energy used in third world and developing nations.
For more information about natural resources, go to http://www.nrcs.usda.gov
Figure 1. Energy Consumption by Source
(from http://www.eia.doe.gov/kids/energyfacts/science/formsofenergy.html)
As technological changes occur, so do the energy demands associated with those changes. These
changing demands frequently prompt the exploration and exploitation of “new” and more
efficient energy resources. Energy sources are often the major focus in the discussion of natural
resources just for that reason.
Looking back at the definition above, it is not difficult to expand the definition to such things as
commercially harvested fish, agricultural products, soils necessary to grow crops, clean “air” and
clean fresh water, and to entire ecosystems that may not have resources extracted from them but
rather are used as tourist destinations, or nesting and nursery ground for innumerable species.
By extending the definition just slightly, the myopic view presented above, it becomes a very all
encompassing view of the world as a whole. At some time or other a resource, any resource, can
be considered a natural resource and one with some degree of value. There may not be a direct
economic value but there is a value that should be considered prior to that resource being used,
or possibly destroyed, specifically when it comes to such things as habitat, soils, and scenic
beauty.
To get the latest status of natural resources in Nevada, go to http://dcnr.nv.gov/nrp01/content.htm
As a general rule natural resources can be broken down into two main categories, renewable and
non-renewable.
Renewable Resources
By definition, a renewable natural resource is a resource that is replaced by natural processes in
a reasonable amount of time. The exact definition of reasonable can be debated, but in general, it
tends to imply that the resource is being replaced at a rate equal to or greater than the rate of
consumption. A properly managed forest that is selectively cut and/or replanted and properly
managed can be considered a renewable resource even though it may take 40 years for the
replanted trees to grow to the proper size to be harvested. Water impounded behind Hoover
Dam is generally considered a renewable resource; however, as is currently the case, the water is
not being replaced in Lake Mead at the same rate it is being withdrawn due to the extended
drought conditions.
The term renewable resource can be somewhat misleading as the water level in Lake Mead can
attest to. The water in the Colorado River is naturally occurring and based on the snow fall on
the western side of the Rocky Mountains. However the amount of rain and snow the western
slopes receive is highly variable so the lake level fluctuates accordingly. In the case of Lake
Mead it has been steadily dropping over the past 7 years. Water is continually moving through
the water cycle, it simply is not pausing in any great abundance on the western slopes of the
Rocky Mountain as of late.
An excellent visualization of the lower water levels in Lake Mead is found at;
http://earthobservatory.nasa.gov/Study/LakeMead/
The variability of a resource to renew itself must be taken into consideration when managing the
resource. Resource management should be a fluid process, one that constantly incorporates new
data into the management plan. Improper management of a renewable natural resource can lead
to its destruction or collapse resulting in that resource, and possibly others, becoming scare, or
non-existent. For example, forests that are clear cut and not replanted can quickly lead to soil
degradation which left unchecked can lead to the soil no longer being able to support the plants
that normally grew there. Another example is over fishing and the building of dams of the
Columbia River; which has lead to a drastic decrease in the supply of salmon available to
commercial fisheries. The reduction in supply has lead to total or severe restrictions being placed
on the fishing seasons and total tonnage of fish that may be harvested each year.
35
30
Chinook
Coho
Chum
Sockeye
Steelhead
25
20
15
10
5
0
18
70
-7
18 9
80
-8
18 9
90
-9
19 9
00
-0
19 9
10
-1
19 9
20
-2
19 9
30
-3
19 9
40
-4
19 9
50
-5
19 9
60
-6
19 9
70
-7
19 9
80
-8
19 9
90
-9
9
Millions of Pounds Caught
Historic Salmon Harvest on the Columbia River Basin
Years
Figure 2. Salmon Harvest over time, data from Project Wild Activity, “Where have all the Salmon Gone!”
(http://myfwc.com/educator/PDF/SalmonGone.pdf)
Wind, solar, hydroelectric, and biomass are frequently referred to as renewable energy sources.
Renewable energy sources should not be confused or equated to “good” or problem free energy
sources. With every natural resource there are costs and benefits to their use.
When discussing the use of renewable and non-renewable resources things are never black and
white. Not only are the students done a disservice if taught that resource use is black and white,
but in some districts it is a direct violation of their rules and regulations, which state that
controversial issues MUST be presented in an unbiased way; thus, allowing the students to form
their own opinions and make up their own minds, based on accurate scientific information.
For more information on the pros and cons of mega-dams, go to
http://ijolite.geology.uiuc.edu/05SprgClass/geo497/class%2013%20/Big%20Dams.htm
In the case of hydroelectric energy, and specifically Hoover Dam, its placement on the Colorado
River forever changed that ecosystem. Not only at the time did it create the world’s largest manmade lake, but it altered the flow of water down the river. Water that once use to flow warm and
slow in the summer and fast and cold in the spring, now flows at a nearly constant rate and a
nearly constant temperature of 57°C. This homogenous cold flow of water and the dam itself has
altered the environment to the point that several native species of fish that were once found on
that section of the Colorado River are now extinct or near extinction.
The trade for this controlled flow is a stead source of water for agriculture, the lack of seasonal
flooding, power generation, and a premier recreational lake at the expense of the river ecosystem
and its indigenous species. Is the state of the river better pre-damming or post damming? This is
not a question that can be simply answered. For the fish, pre-damming is obviously better, for the
millions of people that live in Southern California, Arizona and the Las Vegas region, post
damming has some very obvious benefits.
Several renewable energy sources are often addressed in current science text books. These
renewable sources include, biomass (the burning of plant matter), solar (both Photovoltaic [PV]
and thermal), wind, wave/tidal, and hydroelectric. As addressed earlier with Hoover Dam
(hydroelectric), there are costs and benefits associated with the use of these resources. For
example; biomass requires large tracks of land to grow the plant matter that will be processed
into fuel, or burned. Air pollution and greenhouse gases can be released with its use. Biomass is
renewable as the land can be used over and over to plant new crops, which in turn, can be turned
into the needed fuel. Solar requires substantial amounts of land needed to place the solar panels
or mirrors necessary to generate the desired electricity. Although PV does not generate waste
while they are in use, the manufacturing process does, and some of that waste is toxic. Wind
turbines do not generate waste either, but their operation has been known to kill birds and bats as
well as being a visual detraction from the scenic beauty where they are built. Wave/tidal
facilities can be an eye sore, as well as disrupt the movement of marine fish and mammals. One
distinct advantage common to all these renewable energy sources is that they are practically undepletable. The sun will shine every day, the rain will fall, and the wind will blow; however
there is a great deal of variability from day to day, and season to season. So despite the fact that
the resources can not be depleted, they may not always be available in quantities desired or
locations needed.
U.S. Electricity Net Generation Using Renewable Resources, 1990 and 2010 (Billion Kilowatt-hours)
1990
Conventional Hydroelectric
Reference Case
Annual Percentage Rate of
Growth
2010
1990-2010a
288
306
0.3
Geothermal
15
62
7.2
Municipal Solid Waste
10
54
8.5
Biomass
31
59
3.2
Solarb
1
4
9.2
Wind
2
16
10.4
348
501
1.8
2,098
2,975
1.8
577
636
0.5
3023
4,112
1.5
Total, Renewable Resources
Fossil/Storage/Other
Nuclear.
Total Generation
aAnnual
percentage rates of growth are calculated using unrounded values.
solar thermal and less than 0.02 billion kilowatt-hours grid-connected photovoltaic generation.
Notes: Totals may not equal sum of components due to independent rounding. Electric utility
generation data exclude internal generating station use (net); nonutility data include internal use (gross).
Sources: Energy Information Administration. 1990 data: For utilities, EIA-861, "Annual Electric Utility
Report" for nonutilities, EIA-867, "Annual Nonutility Power Producer Report." 2010 projections: Annual
Energy Outlook 1993, DOE/EIA-0383(93), AEO 1993 Forecasting System run AEO93B.D0918921
(Washington, DC, January 1993).
bIncludes
Figure 3. Energy Generation
(from http://www.eia.doe.gov/cneaf/electricity/pub_summaries/renew_es.html)
Non-renewable Resources
A non-renewable resource is said to be one that can not be replaced by natural means at a rate
equal to or greater than its consumption or it is so poorly managed that it disappears entirely.
Traditional examples of non-renewable resources include, petroleum, coal, and natural gas,
which are commonly called fossil fuels. Additionally, minerals such as uranium, bauxite
(aluminum ore), and iron ore are sometimes included in the list. However, the non-renewable
resource lists could and should include such items, as arable soils (for additional information on
soils see E12C5), potable ground water, habitable land, old growth forest, and species on the
endangered and threatened species list.
Figure 4. Strip coal mine. (from http://www.wy.blm.gov/minerals/coal/)
Renewable resources that are consumed at a rate faster then they can regenerate can lead to their
depletion. Bison use to number in the tens of millions and roam over much of the Great Plains;
however with the introduction of the railroad and the desire to control the Plains Indians, the
Bison were slaughtered to the point that there were less than 1,000 animals left. Over time their
numbers have rebounded to over 350,000 animals. Tropical rain forest land is being cut and
burned to make way for people and for agricultural use. Tropical forest has a regeneration rate
of about 500 years for it to return to its original state. This assumes that the soil has not been
totally destroyed and that plant succession can still take place. (see benchmark L.12.C.2 for
detail on succession)
More details about tropical deforestation can be found at;
http://eospso.gsfc.nasa.gov/ftp_docs/Deforestation.pdf
As stated, there are two main reasons why a resource could be classified as non-renewable: (1)
rate of regeneration and (2) rate of consumption. Many resources cannot be renewed because
conditions are no longer ideal for their formation. Petroleum formation is dependent on large
shallow inland seas. Coal formation depends on large swamps that experience vigorous growth
and rapid deposition of plant matter that does not decay quickly. These conditions are currently
not common on Earth.
To learn more about how fossil fuels were formed, go to
http://www.energyquest.ca.gov/story/chapter08.html
Fossil fuels are the main source of energy for the industrialized world. Coal, petroleum and
natural gas make up 85% of all energy used. These sources are all non-renewable, and at their
current rate of use, non-sustainable. The use of these energy sources has many costs and benefits
associated with them. All are very efficient forms of energy, compared to such things as the
burning of wood. High efficiency means less is needed to produce the same desired effect,
usually the heating of water to make steam which is used to generate electricity. However, with
the use of any and all resources there are costs and benefits. These costs are often enumerated in
current text books and include such things as air, ground and water pollution, greenhouse gas
emission (See E.12.A.2 Atmospheric Composition and E.12.A.3 Greenhouse effect for more
information on this subject.) and habitat destruction associated with their harvesting. Beyond
their efficiency, some of their benefits may include, relative abundance, ease or efficiency of
harvesting, the wide variety of uses for the resource, and the cost/profit associated with the
harvesting, processing and use of the resource.
For more information on renewable resources in the U.S. Electricity Supply see,
http://www.eia.doe.gov/cneaf/electricity/pub_summaries/renew_es.html
For general information on renewable and non-renewable energy, go to
http://www.eia.doe.gov/kids/energyfacts/sources/whatsenergy.html
Sustainability
A key concept associated with the use of both renewable and non-renewable resources is
sustainability. Can the resource be used at a rate that will allow for its continued use for years or
even generations to come? If the answer is no, then the resource is not being used in a
sustainable way.
In order to maintain the supply of a non-renewable resource for generations to come, how that
resource is harvested, used and recycled must be considered.
Gold and silver in Nevada use to be harvested from hard rock mines, where the miners would
drill and blast their way down the ore vein until the gold was no longer visible. The resources
were soon depleted and the miners moved on. This approach to mining is not sustainable.
Today, most of the gold is harvested from deposits that show little or no visible gold. In fact, old
tailings piles left over from played out mines are often reprocessed to remove the “invisible”
gold that was left behind by miners of old. This “new” found gold is available due to the changes
in the methods of mining, brought about in great part to the increased value of gold.
Gold mining in Nevada is a good example of a non-renewable resource that is harvested in such
a way that it is still available. As gold becomes scare and the prices increase, incentive is placed
on finding new methods to extract ever decreasing quantities of gold from ore, and on new
methods to locate entirely new ore bodies.
For information on Gold production in Nevada visit
http://www.patriotgoldcorp.com/page.php?id=2
For more general information on mineral resources, see the following:
Mineral Information Institute has excellent one page resources and lesson plans that can be used
to convey the importance of minerals in our daily lives.
http://www.mii.org/
USGS Mineral Resource Program has information on mineral production in all 50 states by
region.
http://minerals.usgs.gov/about/index.html
Video on Gold this video highlights gold mining in Nevada.
http://www.nevadamining.org/nv_gold/
Colorado Division of Reclamation Mining and Safety this site has additional information
concerning minerals, mining and mine safety.
http://mining.state.co.us/
After harvesting, the way a resource is used is extremely important to consider. Iron is a resource
that was used in great quantities for packaging (cans), automobiles, and buildings. As its price
increased and new materials were discovered or the harvesting methods for those resources
improved, iron was replaced in many of those objects. Drink containers are now made from
aluminum, plastic, and waxed paper. Automobiles have less and less steel (an iron alloy) in
them, due in part from the cost to the materials, but also to cut down on the vehicles mass. The
less mass the vehicle has the less fuel it needs to move it around. So by reducing the amount of
one resource, we can see that relative availability of another resource can be extended.
For information on the composition of an automobile (a quick view of the resources that go into
the making of a car) go to,
http://minerals.state.nv.us/forms/educ/ComposOfAuto.pdf
What happens to a resource after its intended purpose is done, is equally or even more important
than its harvesting. For example, glass bottles are a good way to safely store and to display food
and beverages. But once the bottle is empty, what happens to it? All too often it is thrown away.
This forces a new bottle to be made in order to replace the “lost” one. In order to make the new
bottle, more resources must be harvested. However, the glass, like aluminum and steel/iron, is
100% recyclable. This means, that at the very least, the glass could be reprocessed to form a
“new” glass item, eliminating the need to harvest new raw materials. For every ton of glass
manufactured, close to 400 pounds of waste products are produced. In glass recycling, by
substituting just half of the raw materials with recycled glass, for every ton made, reduces the
amount of waste by over 80%. Of course in many cases, a glass bottle can be cleaned, sterilized
and refilled, being reused for its original purpose, saving even the energy and resources needed
to reprocess the glass.
Aluminum is fairly heavily recycled due to its monetary value; however, it still makes up
approximately 1% of the municipal waste stream. Enough aluminum is thrown away each year
in the United States to build 31,000 commercial airliners. All of that aluminum was recyclable.
For additional factoids on recycling, go to
http://members.aol.com/ramola15/funfacts.html
Performance Benchmark E.12.C.4
Students know processes of obtaining, using, and recycling of renewable and non-renewable
resources. E/S
Common misconceptions associate with this benchmark
1. Students mistakenly believe that ground water is a renewable resource.
Ground water is water trapped in underground aquifers. The water found there could have
been there for thousand if not millions of years. The rate of groundwater recharge is
dependant mainly on two factors. First is the precipitation amount at the zone of re-charge.
The zone of re-charge is the actual location where the water infiltrates the ground. In the
case of the Las Vegas Valley, that would be the Spring Mountains. The second factor is the
permeability of the rock/strata that the water is migrating through on its journey to the
aquifer. Up until the early 1970’s Las Vegas was totally dependant on ground water for its
potable water supply. In the 70 plus years of ground water use, the water table throughout
most of the valley dropped substantially, resulting in ground subsidence and aquifer collapse.
The Las Vegas Springs Preserve is an excellent place to visit to see first hand the effects of
ground subsidence.
To see the historic groundwater recharge rate for the Yucca Mt. area, go to
http://gsa.confex.com/gsa/2001AM/finalprogram/abstract_28588.htm
A map of annual precipitation in Nevada is found at
http://www.ocs.orst.edu/pub/maps/Precipitation/Total/States/NV/nv.gif
2. Students incorrectly believe that using renewable resources is “good” and using nonrenewable resources is “bad”.
Resource use is neither inherently “good” nor “bad.” Rather, it is the method and rate the
resource is harvested, used, and ultimately disposed of that must be considered in the costs
verses benefits analysis of a particular resource. A cost-benefits analysis may yield different
results based on the individual or groups conducting the analysis; however, a comprehensive
analysis will help the students form their own opinion as to whether the costs outweigh the
benefits or visa versa.
Information about the costs and benefits of increasing the use of renewable resources can be
found at, http://www.ucsusa.org/clean_energy/renewable_energy_basics/increasingrenewables-costs-and-benefits.html
An interesting article about the costs and benefits of greening America’s schools can be
found at,
http://www.cap-e.com/ewebeditpro/items/O59F9819.pdf
3. Students mistakenly believe that renewable resources are inexhaustible.
Renewable resources can be exhausted if improperly managed. Fisheries, forests, and fresh
water are examples of renewable natural resources that are management sensitive. If handled
properly, these resources are renewable. However, they are easily over-exploited and can
face total collapse if proper management techniques are not followed. As with all resources,
it is not just the total amount of the resource available that is important, it is how it is
harvested, used, and finally disposed of that will greatly effect it availability. The old slogan,
“Reduce, Reuse, Recycle” comes into play with all resource management.
An interesting article about managing renewable resources is found at
http://aem.cornell.edu/faculty_content/conradRenewable.pdf.
4. Students mistakenly believe that shifting from fossil fuels to renewable resources will
decrease the standard of living.
Standard of living is based on much more than the energy source that is used. When
considering the effect, an energy source will have numerous factors to be considered; many
directly affect standard of living. One of the most obvious factors to consider is the cost of
the end product, whether this it the price of a gallon of gasoline, the cost of electricity per
kilowatt/hour, or drinking water from your tap, the price will largely determine who can buy
it, and who cannot. However, beyond the monetary cost, there other factors that can affect
the standard of living. Using coal to fire a power plant will produce electricity that is very
inexpensive, but will produce by-products such as smoke, air, and water pollution that can
dramatically impact the environment. Cleaning up the environment from coal combustion
adds considerably to the overall cost. On the other hand, using a renewable energy source,
such as wind, will not produce the pollution just mentioned, but can be a visual eye sore, and
the cost per kilowatt-hour of the electricity will be about 3 times more expensive. Which of
these resources has a greater impact on the standard of living? Since standard of living is
based on more than just amount of money a person has, the question becomes very complex.
There is a distinct link between standard of living and quality of life, both of which need to
be considered in making the decisions about what resources to use and how they are used.
More about the combined effort of renewable energy and rate of consumption necessary to
maintain standard of living can be found at
http://www.news.cornell.edu/Chronicle/03/1.16.03/Pimentel-energy.html and
http://dieoff.org/page84.htm
More about renewable energy systems and standard of living can be found at
http://www.news.cornell.edu/releases/Dec02/Alt-energy.hrs.html
For activities from National Geographic on obtaining resources, see
http://www.nationalgeographic.com/xpeditions/lessons/16/g912/web.html
Performance Benchmark E.12.C.4
Students know processes of obtaining, using, and recycling of renewable and non-renewable
resources. E/S
Intervention Strategies and Resources
The following is a list of intervention strategies and resources that will facilitate student
understanding of this benchmark.
1. The Energy Game: Finding Energy Resources
This activity involves students in learning about energy sources. It demonstrates that energy, the
environment and economics are closely tied. During the course of the game and in the discussion
afterwards, students will learn the concepts of scarcity, opportunity cost, net energy profit, law of
diminishing returns, and availability does not mean usefulness. In addition, students will
recognize that as time goes by, energy resources usually become harder to locate and recover,
the price of a particular resource directly relates to the incentive of companies to obtain it, the
obtaining of energy resources has adverse environmental consequences, that technological
breakthroughs commonly affect both the known energy reserves and the ability of society to use
them, and finally that the remaining reserves of fossil fuels are hard to predict and are not known
with absolute certainty.
To access this activity, go to
http://www.beloit.edu/~SEPM/Geology_and_the_enviro/Energy_game.html
2. Energy and the Environment
In this activity, students use scientific information to compare different ways of obtaining,
transforming, and distributing energy from various sources (e.g., fossil fuels, sun, water,
radioisotopes, and solar energy) and how these processes can impact an environment. There is a
teacher resources section with teacher tips and tools in addition to the activity.
This activity can be found at
http://www.bcpl.net/~sullivan/modules/energy8/index.html
3. Renewable Energy: Capstone
This is the culminating activity in the series of lessons on renewable energy. It serves to
reinforce the idea that renewable sources of energy are necessary for a sustainable future, and to
discuss some of the present impacts and potential drawbacks to renewable energy. In the activity,
students will use online resources to research their present energy consumption and investigate
whether it could economically be replaced by renewable sources.
This activity can be found at
http://esa21.kennesaw.edu/activities/renewablecapstone/renewablecapstone.pdf
4. Energy Efficiency and Renewable Energy (EERE)
This U.S. Department of Energy site provides access to more than 600 links and 80,000
documents about renewable energy and energy efficient technologies, including such topics as:
bio-energy, hydrogen, power from the oceans, wind, solar, geothermal, and hydro energy.
Specialized resources include a collection of links to educational and training resources on
energy, a weekly newsletter covering news and events, new sites on EERE, and energy facts and
tips. A consumer section offers advice on energy conservation and home weatherization.
This portal is located at
http://www.eere.energy.gov/index.html
Student activities related to energy efficiency can be found at:
http://www.ucsusa.org/assets/documents/clean_energy/Renewablesready_fullreport.pdf
5. Renewable Energy: Wind
This lesson introduces students to the uses of wind energy. Topics include a history of wind
usage (grinding grain, pumping water, transportation), including the development of wind power
in the United States and its more recent adaptations for producing electricity. There is also
discussion of the physics behind the operation of a windmill and what drives the wind patterns in
Earth's atmosphere. The lesson includes an activity in which students use online resources to
study the relationship between barometric pressure, wind speed and direction. They will collect
data on barometric pressure, wind speed, and wind direction for several days, map it, and look
for relationships between wind speed and direction and the isobaric lines on the map.
This lesson is located at,
http://esa21.kennesaw.edu/activities/wind/windactivity.pdf
6. Renewable Energy Sources Activity
Students will investigate a variety of renewable energy resources, as well as the benefits and
drawbacks of each can be found at
http://www.sciencenetlinks.com/lessons.cfm?BenchmarkID=8&DocID=26
7. Project Wild Aquatics Activity: Where have all the Salmon Gone?
This activity is an excellent way to have the students experience a simplified life cycle of the
Pacific salmon. During the analysis portion of the activity, students will graph the tonnage of
salmon caught over the past several decades. Based on the analysis of the graph, the students
will be able to make connections between natural resources and some of the costs and benefits
associated with their use.
This activity is located at,
http://myfwc.com/educator/PDF/SalmonGone.pdf
8. Nevada Division of Minerals Educational Materials
Extensive list of links and activities from the Nevada Division of Minerals on mineral use in our
daily lives can be found at
http://minerals.state.nv.us/forms/forms_educ.htm
9. Nevada Mining Association
The first link below has excellent information concerning mining in Nevada. The second link
takes you straight to the lesson plans and activities page.
http://www.nevadamining.org/education/mining_nevada/
http://www.nevadamining.org/education/workshops/activities/