Freshwater Studies:

Water Quality & Living Organisms

 

M.B. Elder, Educator, Mathematics & Science Center

 

Developed with funding from the Mathematics & Science Center

 

Major

Understanding

“Limnology” n : the scientific study of bodies of fresh water for their biological and physical and geological properties (ref. Princeton University)

 

Freshwater scientists, called limnologists, study fresh water environments to learn more about the present quality of the water and to study trends in natural succession or human influences on that environment. The quality of the water impacts which and how many organisms can live there. Each type of living organism has a “preference” or “limits” of water quality. Water quality is measured by analyzing the non-living, or abiotic factors. Some of these factors are pH, temperature, dissolved oxygen, total dissolved solids, turbidity, and stream flow. Various equipment can be used to make these measurements, ranging from simple wet chemistry tests to probeware. The biotic environment is analyzed using a macroinvertebrate assessment, or a bioassessment.

 

In this lesson, students will study the abiotic and biotic factors impacting a freshwater environment. They will take and interpret scientific measurements using probeware or alternate tests. They will determine the limitations of freshwater organisms given the abiotic factors of the freshwater environment. They will learn how to predict the quality of a water environment knowing either the water quality or the living organisms.

 

Objectives

Identify key abiotic (non-living) factors that affect water quality, such as, pH, dissolved oxygen, total dissolved solids and turbidity.

 

 

For typical Chesapeake Bay watershed environments in the Greater Richmond area, contrast organisms found when water quality is good (optimum conditions) and when water quality is poor.

 

Use data on abiotic factors to predict the type of organisms that can live in that environment. Conversely, use organisms found to predict the abiotic factors.

 

 

Use water test kits in measuring various abiotic factors and record water quality for each factor.

 

 

Collect living organisms, classify, and use data to make inferences about water quality.

 

Time

Anticipatory Set: Class Survey of Desirable Habitats

5-10 min

 

 

Power Point Presentation, Part 1

15 min

 

 

Simulation 1: Analyzing Abiotic Factors: Data from Two Days at Three Lakes Park

30 min

 

 

Power Point Presentation, Part 2

15 min

 

 

Simulation 2: Bioindicators and Water Quality in the Chesapeake Bay Watershed

30 min

 

 

Paper-Pencil Test: Freshwater Studies

15 min

 

 

Field Study: Bioassessment at a Water Site

90 min

 

 

 

NOTE: If it is not possible to conduct an actual field study, activities in the “Extension” section can be substituted.

 

Materials

Simulation 1: Analyzing Abiotic Data from Two Day at Three Lakes Park

Graphs for Data from Two Days at Three Lakes Park

Simulation 2: Bioindicators and Water Quality in the Chesapeake Bay Watershed

Water Quality Cards

Field Study: Bioassessment at a Water Site

Field Study: Bioassessment at a Water Site - Data Analysis

 

 

State and National

Correlations

Virginia Standards of Learning: Life Science (LS.1, LS.4, LS.7, LS.11, LS.12, LS.14); Biology (BIO.1, BIO.8, BIO.9)

 

National Science Education Standards: Science as Inquiry, 5-8: Populations and ecosystems, Diversity and adaptations of organisms, 9-12: Interdependence of organisms, Environmental quality

 

Instructional

Strategies

Background: This lesson introduces the connection between abiotic (nonliving), biotic (living) factors and water quality. All living organisms depend on abiotic factors to provide the environment they need to survive and grow. Students should be familiar with how limiting factors affect the types of organisms that are found in microenvironments and macroenvironments. See Pushing the Limits: Extremophiles.

 

Power Point presentation: Part I: Abiotic Factors

·        Anticipatory Set: On the board write Temperature—cold (32-50ºF) medium (50-80ºF), warm (>80ºF); Environment—Urban, Suburban, Rural; Motility—SUV, motorcycle, bicycle; Oxygen & Pressure—sea level (Tidewater), Piedmont (Richmond area), mountains. Take preferences for each set of conditions in the class. Tally results for each parameter and draw conclusions for “ideal” student environment.

·        Place four identical clear containers, each with water from a different habitat on a demonstration table. Container 1—swamp water. Container 2—stream or river water. Container 3—aquarium water. Container 4—Tap water. Ask: Which one has the best water quality for the most life? Which one would you live in if you were a trout? A dragonfly? A spirogyra (algae)? A minnow? An E. coli? Does each of these organisms have the same preferences? Did all students have the same preferences?

·        Continue Power Point presentation. Abiotic Factors Influence Aquatic Life. Instructor script is written in notes on slides. Note: Only the major abiotic factors will be presented for discussion. Other abiotic factors--nitrates, phosphates, BOD, etc--should be explained for AP Environmental Curriculums.

 

Simulation 1: Analyzing Abiotic Factors. This may also be presented as a homework assignment.

 

Materials:

Data from Two Days at Three Lakes Park

Graphs for Data from Two Days at Three Lakes Park

 

Students will work with (graph) actual abiotic measurements taken from two different days at Three Lakes Park in Henrico County. The first day is a “typical” fall day. Students will look for trends with temperature and dissolved oxygen. Emphasize that other than a general increase in temperature when the sun is shining on the lake and the resulting general decrease in dissolved oxygen, the other abiotic factors generally stay the same with only slight variations. On Day 2 in the spring, the lake experienced a change in weather at noon. The graphs of the abiotic factors show peaks, dips, and sudden increases. Use inquiry to lead students to understanding why a sudden cloudburst or downpour would affect the abiotic factors. Discuss influences of rainwater runoff from different areas, such as residential, industrial, or construction areas. Also discuss the potential influence of feedlots, fertilizer plants, dog runs, and highly salted roads and parking lots on the freshwater environment.

 

Power Point Presentation, Part II: Biotic Indicators  

Abiotic factors indicate what organisms can live in the water environment. They are limiting factors of the environment. If the abiotic environment is known, the living organisms can be predicted and vice-versa.  When analyzing the health of a water environment, not all organisms in that environment can be tested; it would be too time-consuming and expensive. Macroinvertebrates have been chosen to indicate the health of the environment. Other bioindicators such as bacteria, algae or fish may also be used, but beginning field studies use macroinvertebrates.

 

Simulation 2: Bioindicators and Water Quality

This may also be presented as a homework assignment.

 

Materials:

Water Quality Cards

Bioindicators and Water Quality Data Sheet in the Chesapeake Bay Watershed

 

Students will use eight different sites in the Greater Richmond area. Some information (abiotic factors) is known about the water environment on that particular day. Students will then compare that water environment with the “Organism” cards. Limiting water quality (abiotic factors) requirements are written for each “Organism.”  The “Organisms” include macroinvertebrates, as well as some fish-vertebrates. Students will match the organism to the suitable environment.

 

Field Study: Bioassessment at a Water Site:

Before starting a field study, enlist the expertise of local natural resource personnel. See suggestions in the Teaching Tips section. They will help assess the area around the school grounds for a suitable site. Water studies can be conducted for almost any school--rural, urban, or suburban. Ideal sites would be a stream or river on or close to school property. Drainage ditches and holding ponds work well, too. If the site is off school property, seek permission from the owner. Map area and mark collection sites. Collection sites should be easily accessible. Avoid sites with steep, slippery banks if possible.

 

 If a water site is not available close or on school property, a classroom aquarium can be used. A freshwater aquarium can be stocked using organisms from area ponds, lakes, or rivers. Minimally, the aquarium will need an oxygen source (aerator), thermometer, and pH indicator.

 

Practice/Product

 

 

  • Department of Conservation and Recreation website about soil and water resources in Virginia. Includes information about watersheds and a water quiz.
    http://www.dcr.state.va.us/sw/

 

Closure

Review two different types of water quality indicators: abiotic (nonliving) factors and biotic indicators.

 

Remind students that:

·        Abiotic factors include pH, temperature, dissolved oxygen, turbidity, total dissolved solids, and in streams and rivers-flow.

·        Biotic indicators such as macroinvertebrates, are used for bioassessments.

·        The present condition and history of the freshwater environment can be determined if both abiotic factors and biotic indicators are known.

·        The condition of the freshwater in the local environment in the Chesapeake Bay eventually affects the condition of the Chesapeake Bay.

·        Various types of field equipment can be used to measure and graph water quality.

·        Optimal field studies are carried out over weeks, months, seasons, and years.

 

Extensions

1.     Measure biodiversity in a freshwater environment by creating biofilm communities.
www.mdsg.umd.edu/Education/biofilm/intro.htm

 

2.     Describe the effect of Hurricane Bonnie on dissolved oxygen in Cape Fear River in August/September of 1998.

http://wow.nrri.umn.edu/wow/data/java/rvr/index.html

 

 

Assessment

The following items are provided to assess students’ understanding of the concepts:

·       Paper-Pencil Test: Freshwater Studies

·       Student Project: Freshwater Studies

·       Rubric for Student Project: Freshwater Studies

 

Objective

Paper-Pencil

Test

Product/

Performance

Identify key abiotic (non-living) factors that affect water quality, such as, pH, dissolved oxygen, total dissolved solids, and temperature.

1,2,6

 

For typical Chesapeake Bay watershed environments, contrast organisms found when water quality is good (optimum conditions) and when water quality is poor.

4,5

 

Use data on abiotic factors to predict the type of life found in a pond. Conversely, use life found to predict the abiotic factors

3,7,10

 

Use water test kits in measuring various abiotic factors and note water quality for each factor.

8

 

Collect living organisms, classify, and use data to make inferences about water quality.

9

 

Major Understanding: In this lesson, students will study the abiotic and biotic factors impacting a freshwater environment. They will take and interpret scientific measurements using probeware or alternate tests. They will determine the limitations of freshwater organisms given the abiotic factors of the freshwater environment. They will learn how to predict the quality of a water environment knowing either the water quality or the living organisms.

 

Student Project and Rubric

 

Teaching Tips

Instructor Answer Keys

·        Paper-Pencil Test: Freshwater Studies

·        Simulation 1: Data for Two Days at Three Lake Park

·        Simulation 1: Graph for Data for Two Days at Three Lakes Park

·        Simulation 2: Bioindicators and Water Quality in the Chesapeake Bay Watershed

·        Frequently Asked Questions: Students

·        Frequently Asked Questions: Educators

 

References

Mitchell, Mark K. and Stapp, William B. Field Manual for Water Quality Monitoring, An Environmental Education Program for Schools, Kendall/Hunt Publishing Company, 1997.

Dodds, Walter K., Freshwater Ecology, Academic Press, 2002.

 

Official site of the Chesapeake Bay Foundation

http://www.cbf.org

 

“Meaningful Watershed Experience” definition.

http://www.vanaturally.com

 

Mathematics & Science Center
Information on educational programs available to students, teachers and school divisions and procedures for registering for programs.
http://mathsciencecenter.info

 

Mathematics & Science Center: On-Line Educational Programs
Learn through on-line virtual classrooms, web-based lessons and on-line courses. Access proven lesson plans and instructional modules.
http://MathInScience.info

 

Water Quality Analysis of Swift Creek Reservoir. Addison-Evans Water Production and Lab Facility.

http://www.co.chesterfield.va.us/CommunityDevelopment/Utilities/ReservoirData/

 

The Global Water Sampling Project

http://k12science.ati.stevens-tech.edu/curriculum/waterproj/macros.shtml

 

A field guide to macroinvertebrates.

http://www.fish.washington.edu/naturemapping/water/1fldmac.html

 

http://www.epa.gov/owow/monitoring/volunteer/stream/vms40.html

 

The U.S. Geological Survey's (USGS) Water Science for Schools web site! Information is included on many aspects of water, along with pictures, data, maps, and an interactive center for expressing opinions and testing water knowledge.

http://wwwga.usgs.gov/edu/

 

A good java application of how abiotic/biotic factors change through time.

http://wow.nrri.umn.edu/wow/data/java/rvr/index.html