COURSE: Earth/Environmental Science
I.
Grade Level/Unit Number:
II:
Unit Title: HYDROLOGY
III.
Unit Length: 15 – 18 days (on a 90 min per day block schedule)
IV.
Major Learning Outcomes:
The student will gain an understanding of:
 The role of the hydrosphere in shaping Earth’s surface
 The mechanisms that generate ocean currents
 The various processes and features of active shorelines the features
that form there
 Water resources and issues affecting water quality
 The role of an increasing population on water demands
V.
Content Objectives Included (with RBT Tags):
Objective
Number
1.01
1.02
1.03
1.04
2.01
9 - 12
Unit 5
Objective
Identify questions and problems in the earth and environmental
sciences that can be answered through scientific investigations
Design and conduct scientific investigations to answer questions
related to earth and environmental science:
 Create testable hypotheses,
 Identify variables,
 Use a control or comparison group when appropriate, Select
and use appropriate measurement tools,
 Collect and record data,
 Organize data into charts and graphs,
 Analyze and interpret data,
 Communicate findings.
Evaluate the use of satellite images and imaging techniques in
Earth/Environmental Sciences
Apply safety procedures in the laboratory and in field studies:

Recognize and avoid potential hazards.

Safely manipulate materials and equipment needed for
scientific investigations.
Analyze the dependence of the physical properties of minerals on the
arrangement and bonding of their atoms.
Earth/Environmental Science- Unit 5 DRAFT
RBT
Tag
B1
B6
A4, B4
C3
B4
1
2.03
Investigate and analyze the processes responsible for the rock cycle:
 Analyze the origin, texture and mineral composition of rocks.

Trace the path of elements through the rock cycle.

Relate rock formation to plate tectonics.

Identify forms of energy that drive the rock cycle.

Analyze the relationship between the rock cycle and
processes in the atmosphere and hydrosphere.
B4
2.05
Create and interpret topographic, soil, and geologic maps using scales
and legends (flooding, deposition in delta, wetland buffers, primary
and secondary streams, etc)
B6
4.01
Evaluate erosion and depositional processes: formation of stream
channels, nature and characteristic of sediments, effects on water
quality, and effects of human choices on the rate of erosion.
A4
B4
4.02
Analyze mechanisms for generating ocean currents and upwelling:
Temperature, Coriolis Effect, Climatic influences.
B4
4.03
Analyze the mechanisms that produce the various types of shorelines
and their resultant landforms: Nature of underlying geology, Long and
short term sea-level history, Formation and breaking of waves on
adjacent topography, Human impact.
B4
4.04
Evaluate water resources: storage and movement of groundwater,
ecological services provided by the ocean and fresh water bodies,
impacts of growing human population, natural and manmade
contamination.
A4
B4
4.05
Investigate and analyze environmental issues and solutions for North
Carolina's river basins, wetlands, and tidal environments: Water
quality, Shoreline changes, Habitat preservation.
B4
B6
VI.
English Language Development Objectives (ELD) Included:
NC English Language Proficiency (ELP) Standard 4 (2008) for Limited
English Proficiency Students (LEP)- English Language learners communicate
information, ideas, and concepts necessary for academic success in the content
area of science.
Suggestions for modified instruction and scaffolding for LEP students and/or
students who need additional support are embedded in the unit plan and/or are
Earth/Environmental Science- Unit 5 DRAFT
2
added at the end of the corresponding section of the lessons. The amount of
scaffolding needed will depend on the level of English proficiency of each LEP
student. Therefore, novice level students will need more support with the
language needed to understand and demonstrate the acquisition of concepts
than intermediate or advanced students.
LEP Accommodation Considerations
The following are general suggestions for accommodating English second
language:
1. Assess the prior knowledge of your LEP student and make sure that he or she
has adequate background information in order to execute this activity.
2. Provide graphic organizers or roadmaps illustrating the specific procedures
and expectations of each activity.
3. Provide highlighted text which target key vocabulary and concepts. Review
this text prior to activity.
4. Elicit verbal response of understanding from student. For, example, “Explain to
(or show me) me what you need to do next.”
5. Include marginal notes in activity outline to re-emphasize terms and concepts.
6. Provide visual demonstration in conjunction with verbal instructions
7. Provide immediate feedback and or assessment in order to reinforce
objectives.
8. Provide for alternate forms of assessment such as concept maps, graphic
organizers, verbal explanations, written explanations, or actual performance
rather than strictly pen and paper tests.
9. Provide LEP students the opportunity to peer tutor, pairing those who are on
different proficiency levels.
10. Provide opportunities to demonstrate effective test- taking strategies, regularly
exposing students to sample questions.
Earth/Environmental Science- Unit 5 DRAFT
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VII.
Materials/Equipment Needed:
Activity
What is the role of water in the
images
Water Cycle
Water Budget with SASinSchool
Virtual River
Stream Ecology
Project Wet: Get the
Groundwater Picture
How many people can an
aquifer support?
Watersheds: connecting
weather to the environment
Water Quality For Freshwater
Organisms
Materials
PowerPoint
projector
computer
Drawing supplies such as: small poster paper,
Colored pencils,
Markers
Sample of water cycle on slide or transparency
Access information for SASinschool
Computers with Internet access
One handout:
Balancing the (Water) Budget Handout
Spreadsheet program, such as Excel 2003, or graph
paper
Calculator
Colored pencils
Access information for SASinschool
Computers with Internet access
Virtual River student pages
Access information for SASinschool
Computers with Internet access
Student worksheets
Computers with Internet access
Student worksheets
Computers with Internet access
Student worksheet
Computers with Internet access
Student worksheets
Cold, aerated pond water
800 ml beaker
minnow
hot plate
Celsius thermometer
ring stand
cork
stirring rod
Hach Dissolved Oxygen test kit
data table
graph paper
Earth/Environmental Science- Unit 5 DRAFT
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VIII.
Detailed Content Description:
Please see the detailed content description for each objective in the
Earth/Environmental Science support document. The link to this downloadable
document is in the Earth/Environmental Science Standard Course of Study at:
http://www.ncpublicschools.org/curriculum/science/scos/2004/25earth
IX.
Unit Notes
Overview Of Unit Five
This unit is focused on the use of energy from the sun as it fuels the Water Cycle to
replenish the Earth’s hydrology system. The Water Budget is an essential concept
since we observe and record many human impacts in this category. While nature has a
way of keeping things in check, human beings are known for having negative impacts
on the natural cycling of water in Earth Systems. While learning about the water budget
students will begin to see water as a resource worthy of protection. All living things
depend on clean water and our climates are dependent on the availability of water in the
atmosphere. Fresh Water is delivered to Earth’s surface via a variety of precipitation
types. The intensity, frequency, and duration of water delivery impacts Earth’s surface
through a number of stream and river systems, and erosion and deposition patterns.
The interaction between the atmosphere and Earth’s surface is perhaps one of the most
intriguing areas of study. It is in this area that humans have had a tremendous impact.
Earth’s Oceans, The sun, wind, and Coriolis Effect provide the variables necessary for
heat energy to be distributed around the globe. Water and air are the only “types of
matter” that move from one place to another transporting characteristics of their areas of
origin to new destinations.
Specifically, students will gain an understanding of:
 basic movement of water in the atmosphere, on the surface, and in the
lithosphere
 the limited resource of water on the Earth
 how humans interact with and impact the water budget
 the purpose for conservation of water resources here in North Carolina
 the force of currents which shape shorelines
 the causes of heat energy distribution around the globe
Vocabulary
Abyssal Plain
Alluvial Fan
Aquifer
Barrier Island
Beach
Benthic
Cone of
Depression
Continental
Margin
Continental
Shelf
Coriolis Effect
Deep Ocean
Basin
Deep Ocean
Current
Earth/Environmental Science- Unit 5 DRAFT
Delta
Desalination
Discharge
Fetch
Flood plain
Gradient
Groundwater
Headwaters
Hydrosphere
5
Impermeable
Levee
Longshore
current
Meander
Neap Tide
Oxbow lake
Pelagic
Permeability
Plankton
Porosity
Reef
Refraction
Rip Current
River system
Salinity
Sea level
change
Sediment load
Shoreline
Spring Tide
Stream load
Surface
Currents
Thermocline
Tide
Trench
Turbidity
Current
Undertow
Upwelling
Water Budget
Water cycle
Watershed
Wave
characteristics
In each unit, Goal 1 objectives which relate to the process of scientific investigation are
included. In each of the units, students will be practicing the processes of science:
observing, hypothesizing, collecting data, analyzing, and concluding.
The unit guide gives an overview of the activities that are suggested to meet the
Standard Course of Study Goals for Unit Five. The guide includes activities, teacher
notes on how to weave the activities into the content, and supplementary notes related
to other issues such as preparation time and time to complete the activity. If a teacher
follows this unit (s)he will have addressed the goals and objectives of the SCOS.
However, teachers may want to substitute other activities that teach the same concept.
Teachers should also refer to the support document for Earth/Environmental Science at
http://www.ncpublicschools.org/curriculum/science/scos/2004/25earth for the detailed
content description for each objective to be sure they are emphasizing the specified
concepts for each objective.
Essential Questions for Unit Five:
Following are the essential questions for this unit. Essential questions are those
questions that lead to enduring understanding. These are the questions that students
should be able to answer at some level years after the course. These questions are
designed to incorporate multiple concepts. Students will work on answering these
questions throughout the unit. Teachers are advised to put these questions up in a
prominent place in the classroom and refer to them during the teaching of the unit.
1) Where is water located on Earth? How does it move?
2) What is the role of water in shaping Earth’s surface?
3) How do the variables in a given area influence the balancing of the water
budget?
4) How will water use in our river basin change over time?
5) How might population growth impact water use in my river basin?
Modified Activities for LEP Students:
Earth/Environmental Science- Unit 5 DRAFT
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Those activities marked with a  have a modified version or notes designed to assist
teachers in supporting students who are English language learners. Teachers should
also consult the Department of Public Instruction website for English as a Second
Language at: http://www.ncpublicschools.org/curriculum/esl/ to find additional
resources.
Computer Based Activities
Several of the recommended activities are computer based and require students to visit
various internet sites and view animations of various processes. These animations
require various players and plug-ins which may or may not already be installed on your
computers. Additionally some districts have firewalls that block downloading these
types of files. Before assigning these activities to students it is essential for the teacher
to try them on the computers that the students will use and to consult with the
technology or media specialist if there are issues. Some of these animations also have
sound. Teachers may wish to provide headphones if possible.
X.
Global Content: Aligned with 21st Century Skills
One of the goals of the unit plans is to provide strategies that will enable educators to
develop the 21st Century skills for their students. As much as students need to master
the NCSOS goals and objectives, they need to master the skills that develop problem
solving strategies, as well as the creativity and innovative thinking skills that have
become critical in today’s increasingly interconnected workforce and society. The
Partnership for 21st Century Skills website is provided below for more information about
the skills and resources related to the 21st Century classroom.
http://www.21stcenturyskills.org/index.php?option=com_content&task=view&id=27&Ite
mid=120
NC SCS Biology
1.01, 1.02, 2.01,
2.02, 2.04
21st Century Skills
Activity
Communication Skills
Conveying thought or opinions
effectively
When presenting information,
distinguishing between relevant
and irrelevant information
Explaining a concept to others
Interviewing others or being
interviewed
Computer Knowledge
Using word-processing and
database programs
Developing visual aides for
Earth/Environmental Science- Unit 5 DRAFT
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4.01, 4.05, 4.06
4.04, 4.05
4.01, 4.05
presentations
Using a computer for
communication
Learning new software programs
Employability Skills
Assuming responsibility for own
learning
Persisting until job is completed
Working independently
Developing career interest/goals
Responding to criticism or
questions
Information-retrieval Skills
Searching for information via the
computer
Searching for print information
Searching for information using
community members
Language Skills - Reading
Following written directions
Identifying cause and effect
relationships
Summarizing main points after
reading
Locating and choosing
appropriate reference materials
Reading for personal learning
Language Skill - Writing
Using language accurately
Organizing and relating ideas
when writing
Proofing and Editing
Synthesizing information from
several sources
Documenting sources
Earth/Environmental Science- Unit 5 DRAFT


Water Budget
Stream Ecology
All activities
All activities

Water Budget
Most of the activities can be
presented as opportunities for
students to follow written
directions. The teacher will
have to work with most students
to develop this skill over time.
The following activities are well
suited to developing skills in
following directions:

 Stream Ecology
8
Developing an outline
Writing to persuade or justify a
position
Creating memos, letters, other
forms of correspondence
Teamwork
Taking initiative
Working on a team
4.01, 4.04
4.01, 4.04
4.01, 4.05
Thinking/Problem-Solving
Skills
Identifying key problems or
questions
Evaluating results
Developing strategies to address
problems
Developing an action plan or
timeline
Most of the activities are
designed to be done and
discussed in teams. The
following activities are well
suited to developing team
interdependence skills:

Virtual River

Virtual River

Stream Ecology
Unit Guide: HYDROSPHERE
Total: 15 - 90 min days
ENGAGE: What is the role of water in the images? Show the PowerPoint with the
images and ask the students to decide whether or not the feature is from fresh water
processes or ocean water processes. The answers are found on the last 2 slides of the
power point.
Time: 15 min
Earth/Environmental Science- Unit 5 DRAFT
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Slide 1
What is the role of water
in the following images?
Look at the pictures and then decide whether the
feature is a product of fresh water processes or
ocean processes.
Slide 2
F igure 1
Slide 3
F igure 2
Earth/Environmental Science- Unit 5 DRAFT
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Slide 4
F igure 3
Slide 5
F igure 4
Slide 6
F igure 5
Earth/Environmental Science- Unit 5 DRAFT
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Slide 7
F igures 6-9
Slide 8
F igures 10-11
Slide 9
Fig 1: Wavecut platform in South Wales. Erosion caused by wave action on the cliffs.
http://commons.wikimedia.org/wiki/Image:Wavecut_platform_southerndown_pano.jpg
Fig 2 Wave Rock
Originally Posted by Wave Rock Tourist Website
Wave Rock, a granite cliff, is 15 metres high and 110 metres long. Its rounded shape has been caused by
weathering and water erosion which has undercut the base and left a rounded overhang. This happened
about 60,000,000 years ago when it was exposed. Water from the springs running down the rock during
the wetter months dissolve minerals adding to the colour of the wave. In 1960, some crystals from Hyden
Rock were dated as being 2,700 million years old, amongst the oldest in Australia.
http://www.waverock.com.au/
Figure 3 http://geobloggingwithmark.blogspot.com/2008/01/houston-no-problem.html
Oxbow lakes deposition on the inside of the meander and erosion on the outside, causing the meanders
to become more sinuous over time until one day the river takes a short cut leaving the old meander to silt
up and separate from the river's course forming an ox-bow lake.
Figure 4 http://www.agric.wa.gov.au/ikmp/images/3888024.jpg
All soil contains some salt. Normally it is stored safely and doesn't harm plants. But if high water-using
native plants are removed, extra water will flow through the soil to the ground water, which will bring salt
to the surface as it rises. The salt can be so concentrated that it will kill plants, make our water too salty
to use, and even damage roads and buildings.
Figure 5 http://www.aegweb.org/i4a/pages/index.cfm?pageID=4083
T he G rand C anyon is an impres s ive example of s tream eros ion through rock. F or additional information
on its formation vis it E ros ion E xamples . Image courtes y of E ncyclopedia B ritannica.
Earth/Environmental Science- Unit 5 DRAFT
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Slide 10
F ig ures 6-9: http://lpmpjog ja.diknas .g o.id/kc /b/barrier/barrier-is land.htm
Hurric ane F ran damag ed T ops ail Is land in 1996 (left imag es : befo re, rig ht
imag es of c orres ponding areas : after). Note how the overwas h dam ag ed the
road and even broke throug h the is land in plac es .
F ig ures 10-11 http://c oas tal.er.us g s .g ov/hurric anes /katrina/photo c omparis ons /c handeleur.html
T he firs t image, taken in J uly 2001, s hows narrow s andy beaches and adjacent
overwas h s andflats , low vegetated dunes , and backbarrier mars hes broken by
ponds and channels . T he s econd image s hows the s ame location on Augus t 31,
2005, two days after Hurricane K atrina made landfall on the L ouis iana and
Mis s is s ippi coas tline. S torm s urge and large waves from Hurricane K atrina
s ubmerged the is lands , s tripped s and from the beaches , and erode d large
s ections of the mars h. T oday, few recognizable landforms are left on the
C handeleur Is land chain.
Alternative: Activate prior knowledge by opening up a short discussion on water
movement (cycle). Have students brainstorm all the words they can think of that are
part of the cycle with a short description of where and how it moves in and around the
planet. Students should include the following vocabulary: evaporation, condensation,
water vapor, precipitation, (hail, sleet, snow, rain, fog) run-off, infiltration, transpiration,
etc. You could then collect all the words by writing them on the board for all the groups
to use and group. Depending on the timeframe you have, the students could then draw
a graphic organizer to show how each of these words are related.
Time: 15 min
Alternative: Activate prior knowledge:
Have students make a quick sketch of the water cycle. This is information that is taught
in the 7th and 8th grade. Review terms such as precipitation, evaporation, transpiration,
runoff, surface water, and groundwater. http://ga.water.usgs.gov/edu/watercyclehi.html
Time: 15 min
==================================================================
EXPLORE: Water Budget Balancing the Water Budget SAS in School, a free online
resource for students and teachers that provides standards-based content lessons in all
the core disciplines.
http://www.sasinschool.com/ProductEntrance/Launch/launch.jsp?unit=473
Focus Objectives: 1.01, 1.05, 1.06, 4.04, 4.05
Activity Time: 90 min
Preparation Time: minimal depending on your familiarity with SAS
Safety: n/a
Earth/Environmental Science- Unit 5 DRAFT
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Guiding Question: How do the variables in a given area influence the balancing of
the water budget?
Before the activity: Be sure to get the username and password to access the website
from your media personnel or IT person. Preview the website activity and secure
computers for each student or they may work in pairs to complete the activity. Copy the
worksheet for them to work on. The worksheet has excellent questions and guides
them through the website. You can modify it any way according to your personal
preference.
After the activity: Students should have an understanding that water is not an infinite
resource and that it is constantly in motion and not necessarily in a circle.
==================================================================
EXPLAIN: Virtual River
Focus Objective 4.01, 4.04
Alternate activity: River Mind Map – Illustrations and explanations of stream and river
features – Find examples of river and stream features in selected topographic maps
samples - http://www.coolschool.ca/lor/GEO12/unit6/U06L02.htm
Activity Time: 45 min
Preparation Time: 15 min
Note: This virtual lab will assume that students are familiar with basic computer skills.
The students will have several interactive segments and questions to answer before
moving from one concept to the next. Copy the student pages.
Guiding Question: How does a river work and where/how do they get their water?
Before the activity: You will need to secure computers for the class; students may
work individually or with partners. It is important that you are familiar with the website
beforehand so that you can guide students through the process. Students will need to
be successful in answering questions or the program will not allow them to move
forward to the next concept.
VIRTUAL RIVER
Overview: In this virtual river experience, students learn about stream/river discharge
and flooding.
Purpose: The goal of this exercise is to introduce you to some basic concepts about how rivers
work.
Earth/Environmental Science- Unit 5 DRAFT
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Objective: 4.04
Materials: computers with Internet access, student worksheet
Activity: In the following virtual lab, you will learn about river discharge and flooding.
After logging into the Virtual River simulation, answer the questions below. Record all
of answers to any questions within the simulation on this paper. Should you get “kicked”
out or lose connectivity, you can quickly return to your work space. The program doesn’t
remember your work automatically.
Student worksheet:
Virtual River
http://nemo.sciencecourseware.org/VirtualRiver/Files/page01a.html
Name: __________________
Date: ___________________
Period: _________________
Part 1
River Discharge
1. Define “river”:
2. How do streams get much of their water? Rivers?
What is the relationship between the two terms?
3. Define “discharge”. Be sure to include how discharge is measured. Explain the
measurement of volume. Why is it a cubic measure?
4. How do you estimate the stream’s discharge? Write the equation and give an
example.
5. Answer the questions at the bottom of page 3. Record your answers here.
1.
2.
6. When referring to stream banks, the left and right banks are labeled based on what
criterion?
Earth/Environmental Science- Unit 5 DRAFT
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Answer the question within the text and move to page 5.
7. What variables are measured in stream discharge? What instruments are used?
8. What part of the stream is flowing fastest? Make an educated guess as to why you
believe your answer to be true. Record your answer here.
9. On page 8, read to find out the answer. Were you right? How is average velocity
measured?
10. On pages 9 and 10 copy the data charts and record your answers. Explain how
average velocity is determined.
11. After completing the graph on page 12, make a sketch of the curve –remember to
label your graph properly.
12. Complete the calculations on pages 13-17. Record all of your answers below.
a) Page 13: Determining average velocity
b) Page 14: 6/10’s rule
c) Page 15: Practice calculations of 6/10’s rule
d) Page 16:
e) Page 17:
13. What is the Six tenths rule”? How is it used? Why is it a good estimation of stream
velocity relative to depth?
Earth/Environmental Science- Unit 5 DRAFT
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14. After completing page 18, define meander:
How are meanders produced in a stream system?
15. After reading about stream/river features list and define the features found in a
stream/river:
a)
b)
c)
d)
e)
Record your answers to questions 1-7.
15. How are verticals used to calculate basic information about streams?
Pages 19-21
16. Complete your conversions and print your certificate!
17. After completing River discharge, list what you’ve learned about the following:
a). What variables impact the velocity of a river?
b) What is the relationship between velocity and river depth?
Earth/Environmental Science- Unit 5 DRAFT
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c) What factors might contribute to an increase in a river’s discharge? A
decrease in a river’s discharge?
Part 2 Virtual Flooding
Page 2
1. Floods occur when:
a)
b) Define “Watershed”
c) Define “floodplain”
d) Define “Terrace”
Record the answers to questions 1 and 2.
Page 3
2. Record your answers for questions 1-10 below.
Remember-you will need these if you must carry out this investigation over multiple
computer sessions.
Page 4
3. Record your answers to questions 1 and 2.
Page 5
4. Record your answers for questions 1-5. You will need to use the interactive map to
find some these answers.
Page 6
5. How perennial streams different from ephemeral streams?
Earth/Environmental Science- Unit 5 DRAFT
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6. Recall what you learned in Part 1 River Discharge. Record your answers to questions
1 and 2.
Page 7
7. Copy the data chart and complete using the interactive controls.
Page 8.
8. Follow the instructions on the page and then make a sketch of your final graph.
How might hydrologists use such a rating curve?
Page 9
River stages
9. How are flood stages measured?
10. What does the information communicate?
11. What is a “semilog’ measure? What do the points above or below the line of best fit
tell us?
12. Answer questions 1 and 2.
Page 10
13. Complete the data chart.
Page 11
14. Complete the graph by placing the data points on the graph. Answer the questions.
15. What is a hydrograph and how are they used?
Earth/Environmental Science- Unit 5 DRAFT
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Page 12
16. What accounts for the lag time between rainfall events and river rise?
17. Answer questions 1-3.
Page 13
18. Complete the data chart on this page by reading the hydrographs for each river.
Page 14
19. How do hydrologists and town/urban planners/potential property buyers use
recurrence interval charts?
20. Record the data chart and answers below.
Page 15
21. Complete the rank order and recurrence interval data for the chart. Record your
answers in the space below or copy the table and fill it in.
Page 16
22. Complete the graph and place the curve. Answer the questions at the bottom of the
page. Record your answers in the space below.
Page 17
23. Continue to use the interactive graph to answer questions 1-4 at the bottom of the
page. Record your answers.
Page 18
Probability
24. After reading the information, answer questions 1-5. Record your answers below.
Page 19
Earth/Environmental Science- Unit 5 DRAFT
20
25. Copy the data chart and fill in the missing answers.
Page 20
Wrapping it up
26. Read the information at the top of the page. After interpreting the graphs, answer
the questions at the bottom of the page. Be sure to record your answers below.
Page 21
Conclusions
Page 22
Certificate
27. Print and turn in your certificates (River Discharge and River Flooding) along with
this paper for credit.
On the personal side:
28. After learning about rivers and flooding, how might you use this information in the
future?
29. In your area are there areas prone to flooding? Do a research project on the
probability of flooding in your area. Present your findings to the class. Topics such as
this are excellent for Graduation project material.
30. What is the connection between climate and the life cycle of a river? Give evidence
for your ideas.
After the activity: Students should turn in their worksheets and be able to answer
basic questions concerning how a stream is formed, erosion forces and their locations
based on the direction of the river. Students should understand watersheds and that
water is in constant flux.
Earth/Environmental Science- Unit 5 DRAFT
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==================================================================
EXPLAIN: Stream Ecology
Focus Objective: 4.01. 4.04
Activity Time:
45 min
Preparation Time: 15 min
Notes: In this virtual lab, students manipulate variables that have specific effects on the
living organisms in the stream environment. SAS is a free resource for all NC teachers.
Guiding Question: What are the effects of pollution on a stream and its inhabitants?
Before the activity: You will need to become familiar with the SASinschool website so
that you are able to instruct students on navigating correctly. The instructions are
available along with lab manuals, worksheets and possible assessments. All you need
to do is download and print the ones you want or modify them to fit your needs.
STREAM ECOLOGY
Overview: In this virtual lab, students manipulate variables that have specific effects on
the living organisms in the stream environment. SAS is a free resource for all NC
teachers. http://www.sasinschool.com/ProductEntrance/Launch/launch.jsp?unit=870
Purpose
This InterActivity, designed for use in a 45-50 minute class period, addresses the
following goals:

To develop an understanding of ecological relationships

To assess the impact of various pollutants on a stream and its inhabitants

To interpret data in order to determine how variables interact under real-life
conditions
Prerequisites
Before you use the lesson, be sure to become familiar with the program so you can
instruct students correctly.
To get the most from this InterActivity, the student should be familiar with

Pollution and pollutants
Earth/Environmental Science- Unit 5 DRAFT
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
The concepts of velocity and concentration

Aquatic ecosystems

The use and manipulation of fractions, decimals, and ratios

Drawing and interpreting line graphs
Objectives
The student will

Determine the impact of one or more pollutants on dissolved O 2, temperature,
and species composition

Evaluate and rank different pollutants in terms of the severity of their impacts on
a stream ecosystem

Apply this knowledge to address a fictitious, but realistic, problem
Student Directions:
1. Go to: http://www.sasinschool.com/login
2. Enter the user name: cedarridge
3. In the Quick Launch box, enter: 870
All the following are made available on the website:
Assessment
Lab Manual Answers can be used to evaluate student responses. In addition, the teacher may
request that students prepare a lab report or write-up for this InterActivity. Further use of the
BioScope and/or traditional wet-lab experiences provides additional opportunities for students to
demonstrate mastery.
Printable Materials
Students need individual copies of the Data Sheet to complete the tables, graphs, and/or
diagrams. Since students record all other answers on their own paper, the teacher may wish to
distribute a class set of Lab Manuals to reduce the number of needed copies. Note: if students are
to complete the Analysis & Conclusions section as an out-of-class assignment, they will need
individual copies of that portion of the Lab Manual.
Data Sheet (PDF)*
Data & Observations*
Analysis & Conclusions*
Lab Manual Answers
* Also available within the InterActivity
Earth/Environmental Science- Unit 5 DRAFT
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After the activity: Collect the lab worksheets and the data sheets, observations and
analysis for grading. A short class discussion on what was observed and conclusions
that students have drawn from this experience can take place depending on your time
schedule. It is important to wrap up student thinking to be sure that they learned the
objective.
==================================================================
ELABORATE: Watersheds: connecting weather to the environment
Focus Objective: 4.01. 4.04
Activity Time:
Preparation Time:
Safety:
Notes:
Guiding Question:
Before the activity:
After the activity:
==================================================================
EVALUATE: How many people can an aquifer support?
Activity Time: 30 min
Preparation Time: 10 min
Guiding Question: How does human population effect groundwater reserves?
Before activity: Secure computers for the class. Review the website and copy the
worksheet. Decide if the students will work independently or with partners or if you will
walk through the activity as a whole group. Students should have an understanding of
what an aquifer is and how groundwater moves through the lithosphere.
After activity: You can extend this activity by with an assignment for students to
research the aquifer in their area. At the end of this lesson are websites that can be
used for this purpose.
==================================================================
EXPLAIN: Get the Groundwater Picture – Project Wet
Focus Objective: 4.04
Earth/Environmental Science- Unit 5 DRAFT
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Activity Time:
45 min
Preparation Time: 15 min
Notes: To do this activity you will need computers with Internet access to Classzone:
ES1401 How does Water move through the ground? You will need to decide ahead of
time how to set up the class.
Guiding Question: What characteristics of a rock layer allow it to hold water?
Before the activity: Check out the website to be sure your computers have the proper
plug-ins to play the short animations. Students can work individually or with a partner to
answer questions depending on the number of computers and the space available to
you. Students will need to be familiar with creating and analyzing graphs.
After the activity: Discuss the suitability of sandstone, limestone, and shale as
aquifers for supplying human water needs.
==================================================================
EXPLAIN: How Temperature and Salinity Affect the Density of Water
Focus Objective: 4.02, 4.03
Activity Time: 90 min
Preparation Time: 30 min
Safety: glass breakage, goggles, heat, gloves
Notes: Some supplies can be supplemented with everyday items in the kitchen counter
if lab glassware is not available. Be sure to practice the experiment before the students
so that you can ward off any inaccurate procedures.
Guiding Question: How does salinity in water change water density?
Before the activity: Students should know how to create a chart and then construct a
graph from the data. You will need to gather all the supplies and set up students into
groups for the activity.
How Temperature and Salinity Affect the Density of Water
Materials:
Computer with Internet access
Earth/Environmental Science- Unit 5 DRAFT
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electronic scale
stirring rods
graduated cylinders
5 - 100 ml beakers
food coloring
table salt
5 gallon subdivided glass tank
hot plates
ice
1000 ml beaker for ice bath
access to tap water
thermometer.
Assignment / Instructions:
Subdivide students into 5 groups.
Each group will be assigned a specific amount of salt, a color, and specific a
temperature of water for mixing in the 100 ml beakers. (Note: The water temperature
should be approx. 50 degrees in the half filled fish tank.)
Group #1 – 5 grams of salt, no food coloring, water temperature = 90 degrees
Fahrenheit
Group #2 – 40 grams of salt, red food coloring, water temperature = 50 degrees
Fahrenheit
Group #3 – 80 grams of salt, yellow food coloring, water temperature = 70 degrees
Fahrenheit
Group #4 – 140 grams of salt, green food coloring, water temperature = 45 degrees
Fahrenheit
Group #5 – 220 grams of salt, blue food coloring, water temperature = 35 degrees
Fahrenheit
Each group creates a table to record the following data:
- Weight of the beaker.
- Weight of the beaker and water at the assigned temperature in degrees Fahrenheit
before adding the salt.
- Weight of the beaker and water weight at assigned temperature in degrees Fahrenheit
after adding the salt.
Each group will mix the prepared solution with their assigned ingredients.
Once the each solution is prepared and the mass recordings are made and entered, the
instructor will add each group's solution into the tank while the student observe.
The students should observe the separation of layers by color. This separation will
simulate how ocean currents behave due to the density variations resulting from
temperature & salt concentration in water. This separation will simulate how ocean
currents behave due to the density variations resulting from temperature & salt
concentration in water.
Earth/Environmental Science- Unit 5 DRAFT
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GRAPHING
Have each students create three graphs using the recorded data. The students will use
the computer to graphically illustrate the relationship of water density per salt
concentration, the second graph illustrating water density per change in temperature,
and the third graph should show the relationship of water density per mixture of salt
concentration & water temperature.
QUESTIONS
1) How does salinity in water change water density? How does this experiment support
your conclusion?
2) Which has a greater effect on water density temperature or salinity? How does this
experiment support your conclusion?
3) Based on the observations, where would you suspect the ocean water to have higher
concentrations of salinity?
4) In those regions of the ocean that you would suspect higher concentrations of
salinity, how will water temperature change the ocean currents... will there be an
upwelling or downward flow pattern?
FOLLOW-UP
Have each student search the topic "ocean currents" to find examples of what they
observed in the classroom. For the conclusions, have the student write a one page
summary incorporating the information they found on the web to provide examples
these ocean currents found in different parts of the world and explain why these current
may or may not be beneficial to people who live in these areas of the world.
After the activity: Students should be aware of how to schedule their time to complete
the lab including the clean up after a lab. Be sure to discuss their findings before they
leave.
==================================================================
EVALUATE: ocean 4.02, 4.03
Activity Time:
Preparation Time:
Guiding Question:
Before activity:
After activity:
Earth/Environmental Science- Unit 5 DRAFT
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==================================================================
ADDITIONAL WEB RESOURCES
The Water Cycle. This website provides background information for the teacher on the
water cycle and includes statistics for water distribution along with nice graphics that
can be used for instruction. The USGS water cycle page is available in multiple
languages. This is a great review for students.
http://ga.water.usgs.gov/edu/watercyclehi.html
Watersheds: Connecting Weather to the Environment This website is an excellent
resource to use as a vocal tutorial with simple graphics for your students to help with
clarification, review, or initial understanding. The COMET® Program supports,
enhances, and stimulates learning about atmospheric and related sciences. You would
need to register but there is no fee.
http://www.meted.ucar.edu/broadcastmet/watershed/
Educational Resources for Students and Youth This Web page provides links and
information about environmental educational materials for students and teachers related
to watersheds and water quality protection. The site includes the following four
categories:

Videos/Interactive Materials for Students

Resources by EPA and Other Federal Agencies

Top-Related Water Curricula by Others

Other Resources for Students and Teachers
http://www.epa.gov/adopt/resources/
Give Water A Hand: Leader Guidebook and Action Guide encourages students (9 to
14) to learn about their watershed and take action in their community. Phone: (608)
262-2031; 1-800-WATER20; email: erc@uwex.edu.
Project Globe: Global Learning and Observations to Benefit the Environment. (GLOBE)
is a worldwide network of students, teachers, and scientists working together to study
and understand the global environment. GLOBE students make environmental
observations at or near their schools and report their data through the Internet. The
specific site for background information for the teacher also has a learning activities
listing that offers lessons to be translated into other languages.
http://www.globe.gov/tctg/tgchapter.jsp?sectionId=143
Adopt-A-Watershed uses a local watershed as a living laboratory in which students
engage in hands-on activities, making science applicable and relevant to their lives. It
Earth/Environmental Science- Unit 5 DRAFT
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weaves education with the community developing collaborative partnerships and
reinforcing learning through community service.
Project WET (Water Education for Teachers) facilitates and promotes awareness,
appreciation, knowledge, and stewardship of water resources through the development
and dissemination of classroom-ready teaching aids and through the establishment of
state and internationally sponsored programs. Montana Water Resources Research
Institute (406) 994-5392.
Save Our Streams Tools including the Save Our Streams Watershed Stewardship
Action Kit. The kit covers watershed ecology, water quality problems, and actions
individuals and groups can take to conserve watersheds.
Earth Force/GREEN/ Earth Force is combining the best of the Global Rivers
Environmental Education Network (GREEN) award winning watershed program with its
youth action curriculum. Phone (703) 299-9400.
Groundwater Foundation´s Kids´ Corner has basic information about groundwater,
fun activities and information on how to attend or organize a groundwater festival.
Water Education Foundation has partnered with EPA to develop a number of
environmental educational programs, including Groundwater Education for Secondary
Students. Foundation programs are suitable for students in grades K-14. In addition, the
Foundation serves as the California coordinator for national Project WET (Water
Education for Teachers) K-12 program. All Foundation classroom materials are
consistent with the standards of the California State Frameworks for Science and
History/Social Sciences.
Project Wild & Wild Aquatic. One of the most widely used conservation and
environmental education programs among educators of students in kindergarten
through high school. Ideal for integration into the teaching of science, social studies,
language arts, math, art, physical education, health, music, and other curriculum areas.
Project Learning Tree (PLT) is an award-winning, interdisciplinary environmental
education program for educators working with students in Pre-K through grade12. PLT
helps students gain awareness and knowledge of the natural and built environment,
their place within it, as well as their responsibility for it.
WOW!: The Wonders Of Wetlands is an acclaimed, comprehensive, interdisciplinary
curriculum guide for educators of grade levels K-12. The latest edition, co-published in
1995 by Environmental Concern and The Watercourse (Bozeman, MT), includes more
than 50 fun and effective learning-activities for both indoor and outdoor use. These
activities focus on the three definitive wetland parameters: water, soil, and plants; there
are animal-oriented exercises as well.
The Water Sourcebook series is a popular set of hands-on water activities for all
elementary and secondary grades (K-2, 3-5, 6-8, and 9-12). Designed for use by
teachers, non-formal educators and water quality professionals, the activities teach
youth through experiential learning methods the importance of preserving and
Earth/Environmental Science- Unit 5 DRAFT
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enhancing water resources. The guide covers wastewater treatment, drinking water,
groundwater, surface water, and wetlands. The series was developed with funds from
Legacy, Inc. and EPA.
Chesapeake Bay Foundation Students Bay Saver´s Program Students and adults
alike can participate in a variety of efforts from growing submerged aquatic vegetation
(SAV) to getting involved in restoration efforts.
Home A Syst In every home--large or small, new or old, city or country--there are
potential risks to your family´s health and the environment. Home*A*Syst helps you
identify these risks and take action. Phone: (608)262.0024. Email:
homeasys@uwex.edu.
EarthWater Stencils provides guidance and resources on developing a storm drain
stenciling project and educating the community about storm drain pollution. Phone:
(360) 956-3774.
NATIONAL GEOGRAPHIC EXPEDITIONS
Aral Sea
http://www.nationalgeographic.com/xpeditions/activities/14/aral.html
A Source of Fresh Water: Wilderness Watersheds
(with focus on topographic maps)
http://carhart.wilderness.net/docs/curriculum/7-5.pdf
Watershed Island
St. John's River Watershed Management District (Florida)
Recommended for 6-8 grade
http://sjr.state.fl.us/education/lessonplans/watershedisland.html
Rivers Mind map
http://www.coolschool.ca/lor/GEO12/unit6/U06L02.htm
Mississippi River
http://www.42explore2.com/missriv.htm
USGS Water Science for Schools
http://ga.water.usgs.gov/edu/earthgwaquifer.html
USGS - Water Basics
http://ga.water.usgs.gov/edu/mwater.html
Glossary - Hydro terms
http://ga.water.usgs.gov/edu/dictionary.html
The GetWET (GroundWater Education and Teaching) Observatory at Colorado State
University (CSU) was designed to enhance undergraduate geology courses for majors
Earth/Environmental Science- Unit 5 DRAFT
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and non-majors by providing hands-on, field-based learning opportunities in surface and
groundwater processes. The Observatory is based on educational best practices that
promote experiential and inquiry-based learning in a way that emphasizes the relevance
of the learning activities for students.
http://www.csmate.colostate.edu/getwet/
EVALUATE:
XI.
Sample Assessment Questions
1. What is the source of power behind the hydrologic cycle?
a) Radioactive decay in the Earth’s interior
b) Energy from the Sun
c) The Earth’s magnetic field
d) Convection in the Earth’s mantle
ANSWER: D
RBT Tag: A1
SCOS: 4.04
2. Which of the following choices correctly shows the Earth’s fresh water reservoirs
from greatest to least in terms of volume of water?
a) Atmosphere, lakes and rivers, continental and alpine glaciers, groundwater,
b) Continental and alpine glaciers, groundwater, lakes and rivers, atmosphere
c) Oceans, Continental and alpine glaciers, lakes and rivers, groundwater
d) Atmosphere, continental and alpine glaciers, lakes and rivers, groundwater
ANSWER: B
RBT Tag: B1
SCOS: 4.04
3. The term describing underground layers of rock or sediment which transmit
groundwater is
a) Saturated zone
b) Influent streams
c) Aquicludes
d) Aquifers
ANSWER: D
RBT Tag: A1
SCOS: 4.04
4. What is the major difference between porosity and permeability?
Earth/Environmental Science- Unit 5 DRAFT
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a) Permeability describes the amount of water a rock or sediment layer can hold
and porosity is the ability of the rock or sediment layer to allow water to pass
through it.
b) Porosity describes the amount of water a rock or sediment layer can hold and
permeability is the ability of the rock or sediment layer to allow water to pass
through it.
c) Porosity describes the amount of water a rock or sediment layer can hold and
permeability is the ability of the rock or sediment layer to allow water to pass
through it.
d) Porosity describes groundwater and permeability describes underground oil and
natural gas.
ANSWER: B
RBT Tag: B4
SCOS: 4.04
5. In the saturated zone, pore spaces within rock or sediment can hold
a) Water
b) Air
c) Both air and water
d) Neither air nor water
ANSWER: B
RBT Tag: A2
SCOS: 4.04
6. What topographic feature can separate drainage basins?
a) Ridge
b) Lake
c) River
d) Valley
ANSWER: A
RBT Tag: A2
SCOS:
7. In what type of soil would infiltration occur the slowest?
a) fine sand
b) gravel
c) fine clay
d) silt
ANSWER: C
RBT Tag: A2
SCOS:
Earth/Environmental Science- Unit 5 DRAFT
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8. Flash flooding is a common occurrence in urbanized areas because:
a) more hard surfaces absorb more heat and thus increases the amount of
evapotranspiration
b) the subsurface is generally saturated
c) more hard surfaces decrease the area in which rain water can infiltrate
d) increase of greenhouse gases in urban areas increases the amount of
precipitation.
ANSWER: C
RBT Tag: A3
SCOS:
9. A soil sample that is considered porous:
a) has a high percentage of open space between grains of soil
b) has a wide range of grain sizes in the sample
c) does not allow water to infiltrate easily
d) has mostly large grain sizes in the sample
ANSWER: A
RBT Tag: A2
SCOS:
10. The volume of water that can be stored in an aquifer is NOT dependent on
a) the type of rock
b) the age of the rock
c) the fracturing that has occurred in the rock
d) the rock’s porosity
ANSWER: A
RBT Tag: A4
SCOS:
============================================================================
TITLE - WATER CYCLE
Water Budget - Balancing the Water Budget is a SASinSchool, online resource for
students and teachers that provides standards-based content lessons in all the core
disciplines.
http://www.sasinschool.com/ProductEntrance/Launch/launch.jsp?unit=473
GOALS AND OBJECTIVES
4.01 Evaluate erosion and depositional processes:
Formation of stream channels with respect to the work being done by the stream
(i.e. down-cutting, lateral erosion, and transportation).
Nature and characteristics of sediments.
Earth/Environmental Science- Unit 5 DRAFT
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Effects on water quality
Effect of human choices on the rate of erosion.
4.04 Evaluate water resources:
Storage and movement of groundwater.
Ecological services provided by the ocean
Environmental impacts of a growing human population.
Causes of natural and manmade contamination.
4.05 Investigate and analyze environmental issues and solutions for North Carolina's
river basins, wetlands, and tidal environments:
Water quality.
Shoreline changes.
Habitat preservation.
VOCABULARY
precipitation
evaporation
evapotranspiration
transpiration
condensation
groundwater
recharge
runoff
River Basins and Water Use
Essential Question: How will water use in our river basin change over time?
Supporting Questions:
1. What is the current picture of water use in my river basin?
2. How do various counties within my river basin plan water use for the future?
3. How does the geology of my river basin impact the river’s course?
4. How could a change in precipitation impact the availability of water for use in
my river basin?
5. What industries are found along the primary river in my river basin?
6. How might industry impact water use?
7 How might population growth impact water use in my river basin?
Earth/Environmental Science- Unit 5 DRAFT
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Teacher’s Choice
Required
Activities/Competencies
1. What characteristics define a
river basin?
2. How many river basins are in
= st1 ns = "urn:schemasmicrosoft-com:office:smarttags"
/>= ST1 />= ST1 />North
Carolina?
3. Where do the basins of NC
empty out their contents?
4. How are ecosystems along
the rivers of my basin?
5. What are the climate
conditions within my river
basin?
Product/Performance
Required
1. Notes in notebook
2. Notes
3.Map with basin path
mapped
4. Summaries of
ecosystem,
microclimates, and
unique ecological
situations found in the
basin.
5. Summary chart
using climate data
Assessment –
Required Activities
1.quiz
2. quiz
3. completed WS
4. posters, ppts,
newspaper, etc
5. poster, ppts,
newspaper
Bodily/Kinesthetic
1. Make a board game that can be
played to learn at least 20 facts about
your river basin.
2. Make children’s book suitable for
grade 4 about the importance of the
geology of the river basin.
Verbal/Linguistic
6. Design a study guide for students to use
when studying the river basins of North
Carolina
Visual/Spatial
3. Make an illustrated timeline showing
the discovery dates and the scientist(s)
involved of at least 20 elements on the
periodic table. Include the gender,
nationality of scientist and an
interesting fact about the element.
Naturalist
8. Design a brochure that explains 15-20
facts about water quality in North Carolina.
Information should address the different
issues founding the mountains, piedmont
and coastal plains. Make sure you address
the importance of water both personally
and economically.
9. Create a collage that illustrates where 15
elements on the periodic table occur in
nature. Label each element and provide a
statement about role in nature and source.
Mathematical/Logical
10. Using Excel, generate a spreadsheet
that will help you make a series of graphs
to show the ratio or proportion of.
4. Create visual tool to help others
understand the importance of water in
our everyday lives.
Musical/Rhythmic
5. Select 5-10 important facts about
your river basin and write them into a
song or rap. Perform for the class.
7. Why is learning about river basins
important for North Carolinians? Write a
persuasive essay convincing our class to
see your way of thinking.
Earth/Environmental Science- Unit 5 DRAFT
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==================================================================
Water Quality For Freshwater Organisms
Author: Robert Brosa
OVERVIEW:
In modern day society, there are many types and sources of pollution which directly
affect the environment. One such type of pollution, which is becoming even more
predominate through the construction of nuclear power plants, is that of thermal
pollution. Power plants use vast amounts of water which are converted to steam by the
thermonuclear reaction. This steam is used to turn the blades of the turbines which
turns the generators producing the electricity. The hot water resulting from condensed
steam is partially cooled in specially designed towers before it is released again into the
environment by means of a reservoir or stream. The temperature of the return water is
great enough to raise the temperature of the body of water several degrees. Such
increases in temperature could greatly affect the organisms living in the water.
PURPOSE: The purpose of this activity is to demonstrate to students the effect
increased water temperature has on the amount of dissolved oxygen found in water and
in turn upon the gill beat rate of fish.
OBJECTIVES: Students will be able to:
1. Describe the proper procedure for observing and recording data.
2. Describe how to use the Winkler method for O2 determination in water.
3. Demonstrate how to graph and interpret data.
4. Discuss what effect increased temperature has on the amount of dissolved
oxygen in water and in turn upon the gill beat rate of fish.
ACTIVITIES:
Equipment needed (for each lab group): cold aerated pond water, 800 ml beaker,
minnow, hot plate, Celsius thermometer, ring stand, cork, stirring rod, Hach Dissolved
Oxygen test kit, data table, graph paper.
Day 1:
Step #1 - Place 600 ml. of cold (5 degrees Celsius), well aerated pond water into a 600
ml beaker.
Step #2 - Place minnow into beaker and set on hot plate.
Step #3 - Suspend Celsius thermometer by means of a ring stand and cork in center of
beaker.
Earth/Environmental Science- Unit 5 DRAFT
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Step #4 - Allow minnow to quiet down and take the gill beat rate by counting the
movement (beat) of the operculum which covers the gills. Take the count for 30 sec.
and multiply by 2 to obtain rate per minute and then record count in table of results on
work sheet. (By taking the average of 2 or 3 counts you may be more accurate.)
Step #5 - Turn on hot plate and heat water slowly while gently stirring. Take a count of
the next gill beat rate when the temperature is at 10 degrees Celsius and record data.
(You will need to stop the stirring when the beat rate is taken. A double beaker with
surrounding water may be used if water heats too quickly.)
Step #6 - Repeat steps 4 and 5 at 15, 20, 25, and 30 degrees Celsius, recording your
data each time. If the minnow begins to float at the surface or wildly thrash about
immediately return to cold water as we do not intend for it to die.
Step #7 - Take the recorded data and plot on graph: Gill Beat Rate vs. Water
Temperature.
Day 2:
Step #1 - Same as step #1 above.
Step #2 - Without placing minnow into beaker use the cold water sample and your Hach
water test kit to determine the amount of dissolved oxygen in parts per million (ppm).
Instructions are contained within each kit. All data will need to be recorded on your
worksheet.
Step #3 - Return the amount of water lost from testing to beaker. Place beaker on hot
plate, stir gently, and remove sample for testing when it reaches 10 degrees Celsius.
Step #4 - Repeat Step #3 and test the amount of dissolved oxygen at 15, 20, 25, and 30
degrees Celsius. (If test kits are in short supply or you do not have enough time to make
a test at each 5 degree interval, each lab group may be assigned only a few and the
data taken and averaged for the entire class.)
Step #5 - Make a graph of Dissolved Oxygen (ppm) vs. Water Temperature.
Step #6 - Study each of the graphs which you have made and from your analysis write
your conclusion.
RESOURCES/MATERIALS NEEDED: All explained above.
TYING IT ALL TOGETHER:
The balance of nature, as we often hear, is a very delicate one. Each organism has its
own specific tolerance levels to many different environmental and human imposed
factors. The oxygen level of water is but one of many factors that will determine what
species will be present of survive in a freshwater ecosystem. In today's society we need
to be more aware of how we effect that balance of nature and weigh carefully the results
of our actions and decisions.
Earth/Environmental Science- Unit 5 DRAFT
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==================================================================
Earth/Environmental Science- Unit 5 DRAFT
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