What Impacts Water Quality? Learning Set Three. Teacher Guide

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1 What Impacts Water Quality? Learning Set Three Teacher Guide

2 Content Learning Set Three What Impacts Water Quality? Overview Science Understanding For Teachers Lesson 1/Variables Affecting Water Quality Student Reader/Testing Your Water Lesson 2/Concluding the ph and Fertilizer Investigation Lesson 3/Expanding the Computer Model Lesson 4/Water Testing Student Worksheet/Water Testing Lesson 5/Analyzing Test Results/Making Conclusions Lesson 6/New Relationships With Computer Models Lesson 7/Bioindicators Student Worksheet/Macroinvertebrate Sorting and Identification Lesson 8/What Do the Organisms Tell Us? Teacher Reflection TG 180 Teacher Guide/Learning Set Three

3 Overview Purpose Students will explore the various variables that affect water quality. Students will relate sources of the different chemical and physical factors to the local watershed, land use, and cover. Overview Students engage in a series of benchmark lessons that explore the physical and chemical variables that impact and indicate water quality and conduct tests of their local river to determine water quality. Below are the main instructional events for this Learning Set. During this Learning Set students... - develop conclusions to their ph and fertilizer experiments - evaluate water quality based upon observation of color, turbidity and smell - evaluate water quality based upon biodiversity of macro-invertebrates Major products for teachers to assess: - conclusion of ph and fertilizer experiments - response to driving question based upon physical properties (color and turbidity) - response to driving question based upon bio-diversity Materials Student Reader/Testing Your Water Student Worksheet/Water Testing Student Worksheet/Macroinvertebrate Sorting and Identification Time This Learning Set takes a total of ten days. Review your school calendar and map out a rough schedule. Note school holidays and special occasions that my disrupt the flow of the project. Instructional Events Physical and Chemical Test Benchmark Lessons: Students engage in a series of benchmark lessons about the eight different chemical and physical variables that affect water quality. During each lesson, students learn about what the variable is, its source and how it affects plants, animals, and humans. Computer Based Water Quality Models Using Model-It, students collaborate in the planning, building and testing of their water quality models. Students refine and rework their model built during Learning Set Two which focused on watersheds. Students will build on their models using their understanding of the physical and chemical variables that impact water quality, their sources and their effects on plants, animals, and humans. Teacher Guide/Learning Set Three TG 181

4 Calendar Learning Set Three What Impacts Water Quality 2 class periods Lesson 1/Variables Affecting Water Quality 1 class period Lesson 2/Concluding the ph and Fertilizer Investigation 1 class period Lesson 3/Expanding the Computer Model 2 class periods Lesson 4/Water Testing 1 class period Lesson 5/Analyzing Test Results/Making Conclusions 1 class period Lesson 6/New Relationship with Computer Models 2 class periods Lesson 7/Bioindicators 1 class period Lesson 8/What Do the Organisms Tell Us? TG 182 Teacher Guide/Learning Set Three

5 Science Understanding for Teachers Purpose In this learning set, students investigate specific water quality variables. They measure temperature, dissolved oxygen (DO), biological oxygen demand (BOD), fecal coliform, ph, turbidity, phosphates and nitrates. The combined effects of these variables determine overall water quality. Using test results for each variable, students create an overall, weighted Water Quality Index (WQI). This numerical value can be translated into a qualitative statement about water quality in their river. Next, students investigate overall habitat quality through the biodiversity in their river. Using bioindicator organisms and tolerance values, students determine the overall Pollution Tolerance Index (PTI) of their river. Students learn that the presence or absence of various indicator organisms can be an indication of habitat quality, including water quality through biological response. Students are looking for agreement between what the PTI and WQI methods indicate about the health of the river. Dissolved Oxygen Dissolved oxygen (DO) refers to the concentration of molecular oxygen (O 2 ) dissolved in river water. Aquatic animals need oxygen to breathe and live, but they cannot use the oxygen in a water molecule (H 2 O). It is bonded too strongly to the hydrogen atoms (2H). Aquatic animals can only use oxygen in its elemental form (O 2 ). Most of the oxygen incorporated into the water originates from the atmosphere. However, plant production of oxygen through photosynthesis also provides a substantial fraction of total dissolved oxygen. The amount of oxygen (O 2 ) that can dissolve into water is largely dependent on the temperature and the physical churning or turbulence of the water. Cool waters can dissolve more oxygen than warm waters. Likewise, quickly flowing, turbulent areas (i.e. cascades and riffles) have higher concentrations of dissolved oxygen than slowly moving or still water (i.e. pools and glides). Dissolved oxygen (DO) is essential for the survival of aquatic animals. Organisms such as fish and some macroinvertebrates use their gills to extract dissolved oxygen from the water to breathe and live. As a result, the concentration of oxygen strongly influences which organisms are able to survive in the river. The general trend is for a greater diversity of animals to live in well oxygenated water than in poorly oxygenated water. Rivers should be saturated with dissolved oxygen by the very nature of their movement. Rivers that fall below 90% saturation are considered to be under serious environmental strain. Teacher Guide/Learning Set Three TG 183

6 (Modified from the MDNR, 1989) Biological Oxygen Demand The Biological Oxygen Demand (BOD) of a river is the amount of oxygen used by microorganisms while decomposing organic matter. Microorganisms break down organic matter and combine it with oxygen (oxidation). As organic material and decomposition increase, biological oxygen demand increases and dissolved oxygen decreases. BOD measurements are used to assess the level of organic pollution in aquatic ecosystems. High BOD values most often point to considerable sewage contamination. However, it can also be an indication of increased organic material and decomposition, from excess nutrients (e.g. fertilizer runoff) in the river. Reservoirs or lakes created by damming a river can also have a high BOD. Rivers that are forced to be still are robbed of their natural potential to oxygenate the water through movement. Remember that moving water incorporates more dissolved oxygen than still water. High levels of organic waste and BOD deprive other animals of the dissolved oxygen they require for survival. Some animals are more tolerant of low oxygen levels, such as carp, catfish, sewage worms and midge larvae. Other animals, such as trout, caddisflies and stoneflies, require much more oxygen to survive. Pictures courtesy of Duane Raver, U.S. Fish and Wildlife Service, TG 184 Teacher Guide/Learning Set Three

7 Fecal Coliform Fecal coliform (FC) is a type of bacteria found in the digestive system and feces of humans and other animals. These bacteria can enter the river through sewage overflow, direct human and animal deposit and agricultural runoff containing animal wastes. Fecal coliform bacteria do not cause illness. However, they are easy to measure and are often found in conjunction with pathogens that can make people sick. Therefore, in the interest of practical monitoring, fecal coliform bacteria are measured as an indication of the severity of harmful pathogens. A high concentration of fecal coliform indicates that a high concentration of pathogenic organisms may be present. National Coliform Standards in colonies/100 ml Drinking water 1 TC* Total body contact (swimming) 200 TC Partial body contact (boating) 1000 TC Treated sewage discharge 200 TC *Total Coliform (TC) includes bacteria from coldblooded animals and various organisms. According to some research, total coliform counts are normally about 10 times higher than fecal coliform (FC) counts. *= Return The Michigan standard for fecal coliform in industrial output is 200 FC/100 ml of water. This standard is seasonally applicable (i.e. when beaches are open) and can be suspended November 1 st through April 30 th. The standard can also be exceeded if due to uncontrollable non-point sources, flooding, accident, or emergencies that affect a sewer or wastewater treatment system, according to the Environmental Protection Agency (EPA). With such loose regulation, Michigan fecal coliform standards are ineffective and associated pathogens are often spewed into Michigan waterbodies. ph The ph test measures how acidic or basic a sample is. The ph scale ranges from 0 (very acidic) to 14 (very basic). Neutral samples have a ph of 7. The ph test measures the concentration and ratio of free hydrogen ions (H + ) to free hydroxide ions (OH - ). Neutral samples have a ph of 7 with equal and low concentrations of H + and OH - ions. If a sample has more OH - than H + ions, it is considered basic and has a ph greater than 7. If a sample has more H + than OH - ions, it is considered acidic and has a ph less than 7. It is important to remember that the ph scale The ph scale ranges from 0 (very acidic) to 14 (very basic). Rainwater naturally has a ph around 5.5, slightly acidic (Stapp and Mitchell, 1995). is log scale. For every unit of change on the ph scale, there is a ten-fold change in acidity. For example, a sample with a ph of 6 is 10 times more acidic than a sample with a ph of 7 and 100 times more acidic than a sample with a ph of 8. Changes in acidity can be particularly devastating to aquatic plants and animals. Most living things have adapted to a specific range of ph values. Although the range may be fairly large, deviation from this range can have immediate and dire consequences for stream organisms. Teacher Guide/Learning Set Three TG 185

8 materials, and are further impacted in locations with non-porous bedrock. In places like the Adirondack Mountains, water accumulates on the rocky surface of the area, collecting dry deposition from the atmosphere and acid rain. As a result, one of the most acidic lakes reported by the US EPA can be found in the Adirondack mountains. That is Little Echo Lake with an average ph value of 4.2. ph ranges that support aquatic life (Stapp and Mitchell, 1995). Spring snowmelts can create very acidic conditions in the river. As the snow melts, it releases the acidic water it contained originally, plus all the dry deposition that settled out of the air and into the snow during the winter. As a result, spring snowmelts can create immediate flashes of very acidic water. Rivers can handle gradually melting snow packs more effectively than sudden, large pulses of acidic inputs. Michigan is fortunate to have soils with a natural buffering capacity to counter acidic inputs. During the last glaciation, basic soil and rock (i.e. calcium carbonate) were carved from the Canadian shield and transported to Michigan in the moving ice. As the ice retreated, it left this basic material and the ability to moderate acidic inputs. As a result, our soils and streams are naturally, slightly basic and able to handle minimal acidic inputs. Other areas are not as fortunate. Areas such as the Adirondack and Catskill Mountains in New York, the mid-appalachian highlands, and the mountainous areas of the Western United States are suffering from acid rain inputs into their lakes and streams. They did not receive the benefits of processed basic The natural buffering capacity of the stream can be exhausted. If we continue to add acidic pollutants to our rivers, we will eventually exceed the soil s ability to mitigate our inputs. Therefore, it is important to plan for the future. Legislation that limits pollutants causing acid rain (e.g. nitrogen and sulfur oxides from automobiles and coal-burning power plants), preserves stream and air quality. The discussion of stream ph is an excellent opportunity to connect this learning set to the What is the Air like in Our Community? curriculum if you have already done it. Air pollution and acid rain are the primary sources of acidity in our lakes and rivers. Phosphates and Nitrates Phosphates and nitrates are negatively charged, nutrient ions necessary for the growth of plants and animals. Phosphate (PO 4 - ) is composed of one phosphorous atom and four oxygen atoms. Nitrate (NO 3 - ) is composed of one nitrogen atom and three oxygen atoms. Phosphates are essential in the metabolic reactions and growth of plants and animals. The concentration of phosphate is normally the growth-limiting variable in fluvial ecosystems because it is naturally scarce. Phosphates are attracted to soil particles and organic material. Therefore, soil is the largest natural sink and input (through erosion) of phosphates in rivers. Plants quickly use up the small amounts of phosphates that are released. TG 186 Teacher Guide/Learning Set Three

9 Nitrates also act like a plant and animal nutrient. All plants and animals require nitrogen to produce proteins essential for growth. However, nitrates are naturally very abundant and do not normally limit the growth of stream plants and animals. Therefore, stream organisms are not as sensitive to increases in nitrates. Phosphate increases are the biggest nutrient increase problem, because growth inhibition is lost and more of each nutrient can be used. When this happens, plant populations explode. In fact, phosphate increases are notorious for causing algal blooms, which color the water green. The increased plant growth leads to a higher biological oxygen demand (BOD) as the plants begin to decompose, which in turn leads to oxygen depletion in the river. Human activities can increase phosphate and nitrate concentrations in fluvial ecosystems. These nutrients are quite often found together. Agricultural sources include fertilizer, animal waste and increased erosion by influencing the transport of phosphorous. Major nutrient sources in urban areas include treated and untreated sewage, laundry detergents, and fertilizer runoff. Dissolved solids include inorganic and organic substances. Dissolved inorganic materials are found in ionic form. Many of which are necessary for the maintenance of aquatic life including nitrates, phosphates, iron, sulfur and many other ions found in a water body. Dissolved organic material originates as biological products of soil, plants, and animal material. Dissolved organic material is roughly 50% carbon and can be used as a food source for aquatic microorganisms. High concentrations of suspended solids can cause serious water quality problems. Suspended solids include soil particles from erosion, organic material, industrial waste, sewage and plankton. High concentrations of suspended solids decrease water clarity, blocking the transmission of light through the water, hindering photosynthesis, and absorbing the sun s energy as heat. At the same time, suspended solids can bind to toxic substances and heavy metals. Also, by increasing water temperature, suspended solids indirectly decrease dissolved oxygen. Total Solids Total solids is a measure of suspended and dissolved solids in the water. Dissolved solids are those that cannot be filtered from a sample of water. Suspended solids are those that can be filtered out and removed. Total solids can be measured by evaporating off the water, leaving behind the dissolved and suspended solids. Turbid water contains high concentrations of suspended solids, making the water appear murky or turbid. Turbidity Turbidity is a measure of water clarity. The greater the turbidity, the more murky or cloudy the water. Measuring turbidity is an indication of the abundance of total solids in the water. Turbid water can hinder photosynthesis lowering dissolved oxygen. As a result, turbid water is often(but not always) poor quality water. Teacher Guide/Learning Set Three TG 187

10 Temperature Temperature measures how hot or cold something is and can be defined operationally as what a thermometer measures. Temperature changes can have direct and indirect impacts on aquatic organisms and water quality. Many rivers are groundwater fed and therefore cold. As a result, many stream organisms are adapted to consistently cold temperatures. As we continue to decrease the influence of groundwater and add thermal pollution, we are increasing water temperatures, while decreasing the survival chances of many aquatic organisms. Thermal Pollution Water has a very high heat capacity, making it resistant to temperature changes. Compared to other substances, it takes more energy to raise the temperature of one gram of water by 1 C. This physical property of water moderates daily and seasonal climactic changes in temperature. Large waterbodies also have considerable thermal inertia, a combination between the heat capacity and the size of the waterbody. As the size of the waterbody increases, it is more difficult to change the overall water temperature. Therefore, thermal interia is influential in sizable rivers and lakes. As a result of thermal inertia, large waterbodies are naturally warmer than the air in the winter and cooler in the summer. This property of water has made it an attractive heat sink for industrial processes that require cooling. Industrial activities, such as power plants, can use river water to cool machinery. Afterwards, the water is put back into the river. The water that is released is often much warmer than it was prior to extraction. Industrial cooling is a major source of thermal pollution. Measuring water temperatures above and below a suspected source of thermal pollution can indicate the source and magnitude of thermal pollution. Urbanization alters the water cycle and increases water temperatures. Urbanization often removes streamside vegetation. This eliminates a source of shade that would normally cool the river. Urban pressures also increase erosion by increasing surface runoff and removing vegetation. This results in high concentrations of suspended solids (i.e. turbidity), which also increases water temperatures. Urban pressures also result in greater temperature variation by increasing surface runoff. Urban runoff can be colder than groundwater in the winter, or much warmer in the summer as it moves over heated impervious surfaces, such as roads and parking lots. The net result of increasing urban pressures is warmer average temperatures with greater variation. Direct Impacts Water temperature is one factor that determines which organisms are present in the river. Aquatic animals can be very sensitive to temperature changes. A week or two of high temperatures each year may make a stream unsuitable for the existence of sensitive organisms, even though temperatures are within an acceptable range throughout the rest of the year. Different species have different temperature requirements, but all species can tolerate slow, seasonal changes better than rapid changes. Thermal stress and shock can occur when temperatures change more than 1 to 2 C in 24 hours. High water temperatures increase the sensitivity of aquatic animals to toxic waste, disease and parasites. This can be a result of increased parasite populations, or increased susceptibility during thermal stress or shock. 188 Teacher Guide/Learning Set Three

11 Water Quality Index (WQI) Students will determine the overall Water Quality Index (WQI) for their river. This index is determined by the weighted influence of 8 water quality variables. These variables include temperature, dissolved oxygen (DO), biological oxygen demand (BOD), fecal coliform, ph, turbidity, phosphates and nitrates. Temperature tolerance levels for selected organisms (Stapp and Mitchell 1995). Optimum water temperatures may change for each stage of life. For instance, fish eggs and larvae usually have narrower temperature requirements than adult fish. Temperature changes can alter animal behavior. Temperature cues biological functions in many aquatic animals, such as hibernation and emergence, feeding, reproduction and metabolism. Changing water temperature can entice animals to behave in ways that are not optimal for their survival, such as migrating when they should be hibernating. Some organisms do not perform vital functions at all (e.g. reproduction) until temperature cues are just right. As a result, altering temperature can change animal behavior and ultimately jeopardizes their longterm survival. Indirect Impacts Elevated water temperatures directly and indirectly decrease dissolved oxygen in the stream. Warmer temperatures decrease dissolved oxygen by increasing plant production, decomposition and the BOD of the river. Likewise, increasing water temperatures increase animal metabolism and respiration. This also leads to the depletion of dissolved oxygen in the river. In order to create an overall WQI, raw water quality measurements are translated into comparable numerals. Each test result is translated into a ranking through the tables provided for each variable. This results in 8 ranks, one for each variable. Each variable is also weighted. Weighting each variable depicts the fact that each variable influences water quality to a different degree. Each rank is multiplied by the respective weight for each variable. The sum of the products is the WQI value. This value can be translated into a qualitative statement about water quality (i.e. excellent, good, fair and poor). Biodiversity and Bioindicators Biodiversity refers to the variety of living things in a given area. Biodiversity and individual populations are maximized when habitat conditions are optimal. As a result, biodiversity is often used as an indication of habitat quality, including water quality. When habitat conditions change, plant and animal communities are impacted according to their pollution tolerance. While very tolerant species can withstand large changes in their environment, intolerant species may be eliminated from the changing habitat. As a result, the presence or absence of certain plant and animal species can be an indication of overall habitat quality. Species that react in predictable ways to changes in their environment are known as bioindicators. Teacher Guide/Learning Set Three TG 189

12 Water Quality Index This exercise allows you to determine the overall water quality of your river from your individual test results. First, write the individual test results in the appropriate column in the middle table. Then, using the table at the top of this page, find the ranking that matches your test result. For instance, a BOD reading of 4 ppm is given a ranking of 3. You should write the correct ranking for each test result in the Rank (A) column. Next, multiply the value in the column Rank (A) by the Weight (B) column for each test. Put the answers in the Overall Rank (A X B) column. Add up these numbers to get the Water Quality Index. Once you know the Water Quality index, look at the table below to discover the overall Water Quality of your river. What is the water quality in your river? TG 190 Teacher Guide/Learning Set Three

13 Pictures courtesy of Via- Norton et al, Creatures that are very sensitive to changes or variation in water quality may be exterminated from the river. These species will be replaced by organisms that are more tolerant of changing conditions. Unfortunately, once exiled from the river, it is unlikely that the sensitive species will ever be able to return. As a result, changing river conditions can result in extinction from that site and possibly all other sites as well. The net result can be an immediate loss of biodiversity, and an eventual loss of life entirely. Benthic Organisms as Bioindicators Benthic macroinvertebrates are bottom dwelling, aquatic invertebrates (organisms without a backbone) that can be seen with the unaided eye. These organisms are very important in the stream food web and can be very sensitive to water quality changes. In many cases, benthics are the most important organisms connecting the flow of energy between primary producers (plants) and larger organisms. Many macroinvertebrates found in rivers are larval stages of terrestrial insects such as the dragonfly and black fly. Other common benthic organisms include snails, worms, leeches and crustaceans. Benthic macroinvertebrates are easy to collect and are often used to determine site-specific, long-term water quality. Unlike, chemical and physical tests that determine present concentrations of various pollutants, macroinvertebrate presence and absence provides information about present water quality and past water quality through biological response. The use of macroinvertebrates as bioindicators assumes that polluted sites have fewer organisms than clean sites and that the presence or absence of a certain organism is a direct result of habitat quality. Also, the information provided by macroinvertebrate collections can be considered relatively sitespecific because many macroinvertebrates migrate only short distances. Macroinvertebrates can be subdivided according to feeding guilds, groupings according to feeding habits. The functional feeding groups are: shredders who eat and/or live in dead plant and animal material, collectors who eat smaller pieces of dead organic material, filterers who filter out even smaller particles out of the water, grazers and scrapers who eat only live algae, and predators who eat other benthics (live prey). Macroinvertebrates are often categorized by functional groups, because it is difficult to identify them to family, genus or species. At times it is more important to know the role that each individual plays in the stream ecosystem than its specific name. Teacher Guide/Learning Set Three TG 191

14 difficult to sample the majority of the organisms that are present and nearly impossible to collect them all. Interpret the results of your collection as a whole. If you do not find a particular organism, it does not mean that it is definitely not in the river. It simply means that you did not find one. If the majority of the insects that you collect indicate that the water quality is fair, for instance, stick with it. Do not change your evaluation simply because a few of the other organisms that indicate fair water quality were not found. The flow of energy by feeding guilds in a fluvial ecosystem (modified from R.W. Merritt after J.D. Allan, 1995). Sampling Benthic Organisms Benthic organisms can be located and collected where they feed or rest. Many benthic organisms can be found hiding and feeding in stream vegetation. Organisms that require high levels of dissolved oxygen can be found in riffles where water is flowing over rocks. Benthic organisms that eat dead plant material are often found under leaves near the stream bank. Macroinvertebrate populations vary by season. Keep this in mind. For instance, organisms that feed on fall leaf litter are very abundant in the fall of the year. This does not mean that collection is impossible at other times of the year. Populations may be maximized at certain times of the year, but they are still present throughout the rest of the year. The real trouble may be finding them in a life stage that you recognize. Do not get discouraged if you are having trouble collecting benthic organisms. It can be TG 192 Pollution Tolerance Index Students will be using a Pollution Tolerance Index (PTI) to do a qualitative study of benthic biodiversity in their river. A PTI is useful for detecting moderate to severe pollution. It is based on the presence of indicator organisms (i.e. bioindicators) and tolerance levels. Indicator organisms are those that react in predictable ways to habitat changes. This method assumes that the presence or absence of a certain organism is a direct result of habitat quality, including water quality. In order to create a PTI value, each organism is assigned a value relative to its sensitivity to water quality changes. In this PTI, individual tolerance values/groupings range from 1 to 4. Low values are assigned to tolerant organisms that can withstand severe water quality changes or degradation. High values signify that the organism is very sensitive to changes in water quality and can be easily eliminated from the site. As a result, the presence of organisms with high indicator values (e.g. caddisfly larvae) implies that the river is healthy. The absence of many of these organisms indicates poor stream health. Students determine the PTI for their stream using the illustrated key and worksheet provided. First, students identify each organism Teacher Guide/Learning Set Three

15 by matching the organisms to the pictures. As they identify each organism, they mark a one on the worksheet by its name. Each type of organism only gets one number. Therefore, this method only provides information about biodiversity and does not reflect the concept of abundance. Next, all the ones are summed up for each group and multiplied by the group number (i.e. tolerance value). The sum of these values is the overall PTI, which translates into a qualitative estimation of stream quality (i.e. excellent, good, fair and poor). Students are looking for agreement between the overall Water Quality Index and the Pollution Tolerance Index. Hopefully, the two tests will result in the same qualitative statement about the health of the river. Keep in mind that the PTI relayed information about the entire health of the stream ecosystem. The WQI only assessed 8 water quality variables. The PTI actually tells you much more about stream health, while the WQI gives a good indication of water quality specifically. If the WQI and PTI do not agree, the difference can be an indication of the physical condition of the stream habitat, which can be difficult to measure or quantify. Summary In this learning set, students investigate the habitat quality of their river, including water quality. Through benthic organism collections and water quality tests, students make the connection between water quality, habitat quality and biodiversity. At the termination of this learning set, students should have a good understanding of several water quality issues and the impact that they have on aquatic organisms and human users. Pollution Tolerance Index School Testing Location (River, Main, Cross Streets and/or Bridge Date: Time Air Temperature Latitude Longitude Weather Condition Branch of the Rouge River (Circle One) Main Branch Upper Branch Middle Branch Lower Branch Main Stem For each type of organism that you find in your river sample, place a one in the column next to its name. when you are finished identifying all the organisms, add up all the ones for each group and write the total where it says Total (Sum)= for each group. Next multiply the total value with the group number and write the new value where it says Total X# for each group. Add all these new values together to get the Pollution Tolerance Index Value for your river. GROUP 4 Caddisfly Larvae Dobsonfly Larvae Gilled Snail Mayfly Numph Riffle Beetle Adult Stonefly Nymph Water Penny Total (sum)= TOTAL X 4 GROUP 3 Clams Cranefly Damselfly/Dragonfly Nymph Scud Sowbug Total (sum)= TOTAL X 3 GROUP 2 Flatworm Midge Blackfly Larvae Water Mite Total (sum)= TOTAL X 2 GROUP 1 Blood Midge Larvae Leeches Maggot Pouch Snails Tubifext Total (sum)= TOTAL X 1 Pollution Tolerance Index - GROUP 4 + GROUP 3 + GROUP 2 + GROUP 1 = Pollution Tolerance Index Value Habitat Quality 23 and above = Excellent = Good 11-6 = Fair 10 or less = Poor What is the habitat quality in your river? Teacher Guide/Learning Set Three TG 193

16 Science Understanding Resources Field Manual for Water Quality Monitoring from GREEN Chapter 3: Nine Water Quality Tests. This chapter discusses physical and chemical factors, their sources and their effects and methods of testing them. Chapter6: Benthic Macroinvertebrates. This chapter discusses multiple methods for benthic macroinvertebrate collection and several specific organisms that students may find. Nine Water Quality Tests Compiled by Karen Amati Provides background for students about each of the nine physical and chemical factors that impact water quality in terms of what they are, their sources and their affects. The reading also describes how to perform each test in terms of how students will perform the tests during the project. Water Studies for Younger Folks: A Water Activities Manual for 5 th -8 th Grades The entire book gives you and your students background information on the factors, how to test the factors, their sources, and their effects. TG 194 Teacher Guide/Learning Set Three

17 Teacher Terms to Know Acidic- having a greater concentration free hydrogen ions (H + ) than hydroxide (OH - ) ions. [H + ]>[OH - ] Algal bloom- rapid growth of algae stimulated by excess nutrients. Basic- having a greater concentration of free hydroxide ions (OH - ) than hydrogen ions (H + ) ions. [H + ]<[OH - ]; same as alkaline Benthic- (adj.) bottom-dwelling; (n.) bottomdwelling organism Biodiversity- biological diversity in an environment as indicated by the number of different plant and animal species Bioindicator- a living organism that reacts in a predictable way to changing habitat conditions Biological Oxygen Demand (BOD)- the amount of oxygen required by microorganisms for the decomposition of organic material; same as biochemical oxygen demand Buffering Capacity- ability to neutralize both acids and bases and thereby maintaining the original acidity or basicity of the solution Cascade- an area of a stream or river where the flows are very turbulent usually when moving over large boulders and considerably changing elevation Collector- organisms that eat small pieces of dead organic material (O 2 ) dissolved in river water Fecal Coliform- bacteria found in the colon and feces of humans and animals Filterers- organisms that eat by straining small food particles out of the water Glide- a area of a the stream having laminar flows, very smooth and continuous; where the surface of the moving water appears very calm and flat Grazers- organisms that consume live algae and diatoms Heat Capacity- the amount of energy it takes to warm one gram of a liquid 1 degree Celsius. Herbivore- eats plant material Macroinvertebrate- invertebrates (organisms without a backbone) that can be seen with the unaided eye Metabolic reaction- the chemical changes in living cells by which energy is provided for vital processes and activities and new material is assimilated Nitrate- negatively charged, nutrient ion composed of one nitrogen atom and three oxygen atoms (NO 3 - ). ph- an expression of both acidity and alkalinity on a scale of 1 to 14, with 7 representing neutrality. Numbers greater than 7 indicate alkalinity. Numbers less than 7 indicated acidity. Dissolved Oxygen (DO)- molecular oxygen Teacher Guide/Learning Set Three TG 195

18 Phosphate- negatively charged, nutrient ion composed of one phosphorous atom and four oxygen atoms (PO 4 - ). Pollution Tolerance Index (PTI)- an estimation of habitat quality based on the presence and absence of bioindicator organisms and tolerance values Pool- (1) a small and rather deep body of usually fresh water (2) a quiet place in a stream Predators- Animals that consume other living organisms Primary Producers- living organisms that produce their own energy from sunlight by photosynthesis (e.g. plants) Protein- naturally occurring substances that consist of amino-acid residues joined by peptide bonds and contain the elements carbon, hydrogen, nitrogen, oxygen, and occasionally other elements. Riffle- portions of the stream where the flow is slightly turbulent, usually when moving over rocks, where the surface of the water appears to be rippling Scrappers- Organisms with specially designed mouth parts adept to eating algae and other organic materials pressed against other surfaces Shredders- organisms that chew and mine into dead organic material Temperature- degree of hotness or coldness measured on a definite scale (i.e. thermometer) Thermal Inertia- the resistance to temperature change, increasing as the heat capacity and size of a waterbody increases Thermal pollution- significantly heated or cooled water in a natural waterbody at a temperature harmful to the environment; temperate extremes Thermal stress- when an organism goes into a state of shock due to rapidly changing or extreme temperatures, increasing the organism s risk of further illness Total Solids- In hydrology, dissolved and suspended materials in water Turbidity- a measurement of the clarity of water. It is used as an indication of total suspended solids. Turbulence- the physical churning or movement of water; departure from a smooth flow Water Quality Index (WQI)- an estimation of water quality based on the weighted influence of measured water quality variables TG 196 Teacher Guide/Learning Set Three

19 Lesson 1 Variables Affecting Water Quality OVERVIEW AND OBJECTIVES Learning Objectives Using ideas generated in class and manipulatory oxygen probes, students explain how new variables affect water quality. Assessment Criteria The variables affecting water quality will include, total solids, turbidity, fecal coliform and dissolved oxygen. Student explanations will include how each variable affects both plant and animal life. Purpose Students learn about and test for the various chemical and physical variables that affect water quality. PREPARATION Set-up Teacher should review experiments, create notes of their interpretation and experiment with computer probes Materials Water Quality Jars Flashlight Four Water samples of various temperatures Dissolved oxygen probes Student Reader/Testing Your Water Time Two fifty-minute periods. Variables introduced in this session include: Total Solids Turbidity Fecal coliform Dissolved Oxygen Biological Oxygen Demand Set aside 5-10 minutes each day for students to continue making observations of their experiments. This can either be done at the beginning or end of the class period. Teacher Guide/Learning Set Three TG 197

20 INSTRUCTIONAL SEQUENCE INTRODUCING THE LESSON What are some investigations that we have recently conducted hat might effect water quality? - Fertilizer (containing Nitrates and Phosphates) - Acids (ph) - Soils (erosion and deposition) Don t forget to provide students time to make their experimental obser- Discuss with the class some substances that might be found in our river, for example, if you used a strainer in our river what might you find? or if we took a bucket of water from our river what would we find in the bucket other than just clear water? How might substances get into the water? - Reflect back to the stream table activity - Focus the students on the concepts of: Run-off, which can create non-point source pollution Combined sewer overflows, a point source pollution Erosion Deposition Affects of land cover and use Based upon our experiments, models, walks, and videos, what are some possible effects of these substances being in the water? - Fertilizer increase in plant (algae) growth - ph - decrease in plant growth (less food and habitat) - ph - decrease in biodiversity (some organisms can only live in neutral water) - Soil- murkyness, plants decrease, block up some organism s gills - Sewage- increase algae and bacteria and poison organisms Have students (either as whole groups or one per group) select one of the terms below and read the appropriate sections in the reader and answer the questions at the end of their section to present to the class. - Total Solids -Turbidity - Fecal Coliform Establishing links to the Driving Question Facilitate connection to the driving question. This may be accomplished by: - revisiting past activities (river tank, water jars, virtual tour/video or walk) and asking probing questions such as: TG 198 Teacher Guide/Learning Set Three

21 - What is the turbidity of the water? - Was the river murky? -Was there a lot of "stuff" suspended floating in the water? - Do you think that the river absorbs a lot of light? - Do you think that there is a high or low amount of total solids in the river? Why? CONDUCTING THE LESSON Retrieve the water quality sample jars used at the beginning of the project. These jars can be used as examples of turbidity and total solids. Turn off lights and shine the light through the turbit, and clear jars. If time permits create a jar with solids in it, use sand or twigs. - Ask students how plants would grow in each? - How would the solids in the water affect plants and organisms? - What might cause the material to get into the water? - Have you ever seen a river that looks like the murky jar? Ask the students how might we prevent water from having high turbidity, high total solids or high levels of fecal coliform? (Optional- in groups, have students come up with measures or ways humans can prevent rivers from having unnaturally high levels of the variables listed above. Discuss what local communities and students can do to prevent pollution in water ways.) CONCLUDING THE LESSON Using new concepts have students answer either as an exit question or in their journals: - How do total solids and turbidity affect how much light penetrates the water? -How do total solids and turbidity affect the temperature of the water? - How does Fecal Coliform get into the water? - What are some measures we can take to prevent high turbity, total solids and fecal coliform from getting in the water? - How do you think total solids and turbidity impact the quality of the water? Jig Saw Strategy One strategy to utilize for this lesson is to have different groups each focus on one topic (you will have to use the topics twice). These expert groups then share their findings with the rest of the class. This sharing can be linked to the past activities and experiences. The expert groups explain to the class how their variable helps determine water quality. Newspapers Encourage students to bring in water quality articles to add to the driving question board to facilitate ownership. HOMEWORK Assign the Student Reader/Testing Your Water. Teacher Guide/Learning Set Three TG 199

22 INSTRUCTIONAL SEQUENCE Lesson 1 (Cont.) INTRODUCING THE LESSON Ask class to describe water quality variables identified yesterday. - What are these variables? (Turbidity, total solids, fecal coliform) - How do they get in to the water? - What are some of their effects? Go over questions from Student Reader/Testing Your Water. CONDUCTING THE LESSON Transition the class by explaining that today we will continue our talk about substances in the water that affect water quality. Ask the class what do fish and humans have in common? (They both breath air.) How do fish breath under water, where do they get oxygen? Introduce the following terms by either writing them on the board or at student tables. - Dissolved oxygen - Biological oxygen demand Explain why DO is necessary for aquatic life. Guide the class through the difference between dissolved oxygen and the oxygen atom found in the water molecule. - Can someone describe the chemical formula for water? -If we could use a really powerful microscope to see molecules, what would oxygen dissolved in water look like? - Emphasize that the oxygen molecule is a different and separate than the compound water. (Optional Activity) Using ball and stick models or gumdrop models to illustrate the mixture of water and oxygen will reinforce the difference between dissolved oxygen and the oxygen atom in the water molecule. Using these models, place ten to twelve water molecules and 3 or 4 oxygen molecules in a container to represent the dissolved oxygen mixture. TG 200 Teacher Guide/Learning Set Three

23 Relationship Between Temperature and DO In front of the room, set up four different glasses of water of differing temperatures (ie: from very cold, cold, room temperature, and hot.) Set up the dissolved oxygen and temperature probes on a computer along with a method for displaying. Review with your students molecular motion and change in energy levels with change in state of matter (solid:molecules barely move and are close together, liquids: some movement and molecules are farther apart, gas: molecules move fast and are as far apart) - when heat is added molecules move faster and farther apart - when heat is taken away, or made cooler, molecules slow down and come closer together - when water is cold, oxygen slows down and can be closer together, where as when it heats up oxygen will move faster and want to be farther apart. Cold water can then hold more dissolved oxygen than warm water. Have the class make a hypothesis on which water jar will have the highest dissolved oxygen. Use the probes to measure dissolved oxygen and temperature. Start with the coldest jar and move to the hottest jar. Prompt the students to note the results on the computer screen. Hold a brief class discussion on the results and have students record in their notebook. Relationship Between Amount of Stirring and DO. Maintain set-up and select the jar at room temperature. Record the DO to start which will serve as the baseline. As you are waiting have the students set up their graphs in their journal to record the various levels of DO Vigorously stir water and then record DO. DO might be difficult for students to comprehend especially the relationship between temperature and levels of DO. Share with students examples they might be familiar to help students make this concept relevant. For example, the most abundant fish populations come from the depths of the cold Atlantic and PAcific oceans. Many organisms can t live where companies dump warm waste water back into rivers. Blue ribbon trout streams are usually very cold and have abundant amounts of oxygen. Ask students when would a river be stirred up like the water in the jar? Prompt students to suggest rapid streams, after a storm, streams with many rocks and boulders and mountain streams. Teacher Guide/Learning Set Three TG 201

24 Discuss with students whether stirring or water being tumbled around is good for organisms. See side bar, for example you can mention many good fishing streams have much mixing of the water, or why storms are important to lakes, so that the water can be mixed and oxygen added. Hold a brief class discussion on the results and have students record the data in their journal or in a graph. CONCLUDING THE LESSON How do these demonstrations relate to an actual river and to our river? What affects the amount of dissolved oxygen? Is water with low amounts of oxygen good quality water? How is dissolved oxygen used? Where does the oxygen come from? TG 202 Teacher Guide/Learning Set Three

25 Learning Set Three Student Reader Teacher Version TESTING YOUR WATER Testing procedures are found at the end of this reader. In class, you have been investigating the question, "What is the water like in our river?" You have learned about your watershed and about how erosion and deposition can alter the shape of a river. But how will you know if the water is safe for swimming? Or, drinking? By performing water quality tests you can tell if water is safe to touch or to drink. These tests will also determine if the water is acceptable for living organisms such as fish, plants and other small creatures. These organisms are an important part of the food chain; they help us decide whether the river or lake is healthy or if it needs help. When humans add pollutants to the river, they can change the health of the river. There are two main sources of pollution. Point source pollution enters the water from a specific place. They include paper and pulp mills, meatpacking plants, food processing industries, and wastewater treatment plants. We can test water coming out of a pipe and see if it contains harmful material. Nonpoint sources of pollution come from large areas of land and do not have a direct identifiable source. They include urban runoff, pet wastes, lawn fertilizers, leaves, and agricultural runoff. When scientists test the water quality, they measure specific properties of the water. For example, they may take the temperature of the water and use that as an indicator of how healthy the water is. You will test your particular section of the Grand River watershed (or whichever river you are investigation). The results of these tests and your knowledge of watersheds will be used to determine the overall water quality of a particular section of the river. The following pages will give you information about 8 of the water quality tests. They are: dissolved oxygen total phosphate biochemical oxygen demand nitrates fecal coliform turbidity ph temperature 1. What is "water quality"? Teacher Guide/Learning Set Three TG 203

26 2. In the following list, which are point-source pollutants and which are non-point source pollutants. Explain your reasoning. Golf course Barrel of gasoline Lawn fertilizer Outlet pipe Acid rain Factory Dissolved Oxygen Dissolved Oxygen (DO) is important for healthy rivers. All aquatic animals need oxygen to survive. Testing for DO can help us determine the health of a body of water. Although an oxygen atom is present in every water molecule (the O in H2O), animals cannot use this oxygen because it is strongly bonded to the hydrogen atoms. Aquatic organisms must have a continuous supply of oxygen gas (O2) dissolved in the water. Dissolved oxygen is an oxygen molecule (2 oxygen atoms bonded together, O2) surrounded by many water molecules. In the diagram below, how many dissolved oxygen molecules (O2) are in the water sample? H 2 0 H 2 0 H 2 0 H 2 0 H 2 0 H 2 0 H2 0 H 2 0 H H 2 0 H 2 0 H 2 0 H H 2 0 H 2 0 H 2 0 H 2 0 H H 2 0 H 2 0 H 2 0 Figure 1. This illustration demonstrates how oxygen molecules can be dissolved in water. You should have found 3 dissolved oxygen molecules in the diagram. It is similar to dissolving sugar in water. Solid sugar particles can dissolve. When dissolved, the sugar spreads throughout the water. Similarly, gaseous oxygen molecules dissolve and are spread throughout the water. Most of the dissolved oxygen in water comes from the atmosphere. Waves and tumbling waters mix atmospheric oxygen into water. Through photosynthesis, algae and rooted aquatic plants are also a source of dissolved oxygen. Waters with consistently high dissolved oxygen levels are most likely healthy and stable environments. Natural and human changes to the aquatic environment can affect the amount of dissolved oxygen available to the organisms. TG 204 Teacher Guide/Learning Set Three

27 Dissolved oxygen is measured in units called parts per million, or ppm. For example, if you took a water sample that had a DO content of 8 ppm, it would mean that for every 1 million molecules, there would be 999,992 molecules of water, and 8 molecules of oxygen. The amount of dissolved oxygen needed to support aquatic life depends on the type of animal being considered. Fish cannot live in water with dissolved oxygen content that is less than 4 parts per million (see Figure 2). That can be difficult to visualize, so let's assume that a sample of water is represented by a million pennies stacked one on top of another. The stack would rise 1 mile high! Just 4 pennies of this stack would represent the minimum level of dissolved oxygen needed to survive. It is very small, but an essential quantity. Figure 2. Fish depicted with dissolved oxygen. Out of 1 million parts of water, this fish only needs 4 parts to be dissolved oxygen. Cold water can hold more dissolved oxygen than warm water. Water at 28oC can hold up to 8ppm dissolved oxygen. Water with a temperature of 8oC can hold up to 12 ppm of dissolved oxygen. Dissolved oxygen is measured in a unit called percent saturation. This is how full the water is with dissolved oxygen. For example, if water at 28oC has 8ppm of dissolved oxygen, we say it is 100% saturated. That is as much dissolved oxygen water at that temperature can hold. If that same sample of water had 4ppm of dissolved oxygen, it would be 50% saturated. High levels of bacteria from sewage pollution or large amounts of rotting plants can cause the percent saturation to decrease. This can cause large changes in the dissolved oxygen levels throughout the day. It will affect the ability of plants and animals to live. 3. What is dissolved oxygen? Draw a picture to represent your explanation. Teacher Guide/Learning Set Three TG 205

28 4. Why is dissolved oxygen beneficial for organisms that live in the river? Biochemical Oxygen Demand Living organisms need oxygen to survive. Biochemical Oxygen Demand (BOD) is a measure of the dissolved oxygen used by bacteria as they breakdown waste. In slow moving and polluted rivers, bacteria use much of the dissolved oxygen. This prevents other organisms from using the dissolved oxygen. Organic materials are things that are or once were alive. This includes leaves, fish, birds, plants, algae, and humans. These living organisms eventually die and begin to decay. The bacteria that breakdown these materials use up the dissolved oxygen in the water. Fertilizers contain nitrates and phosphates that help plants grow. This is both good and bad for water quality. It is good because as river plants grow, they photosynthesize and produce oxygen. It is bad for water quality because when the plants die, bacteria break them down and use up the dissolved oxygen in the water. L Figure 3. Decomposing Leaf litter Figure 3. Decomposing leaf litter. Leaves and other organic debris fall to the bottom of the river and are decomposed by bacteria. The bacteria use dissolved oxygen in the water. In rivers where bacteria use a lot of the dissolved oxygen, organisms that are more tolerant of lower dissolved oxygen levels may increase. Organisms that are intolerant of low oxygen levels will either leave or die. 5. What is biological oxygen demand? 6.What would make the biological oxygen demand increase? TG 206 Teacher Guide/Learning Set Three

29 Temperature Temperature is very important to water quality. Temperature affects the amount of dissolved oxygen in the water, the rate of photosynthesis by aquatic plants, and the sensitivity of organisms to toxic wastes, parasites, and disease. As the temperature increases, the amount of plant growth increases. This is good because it adds dissolved oxygen to the water, but plant growth can increase too much. The plants will eventually die and decomposing bacteria will use up the dissolved oxygen. Heated water from industrial operations is often added to rivers. This is known as thermal pollution. It can cause temperature changes that threaten the balance of the river s ecosystem. For example, if the water gets too hot, certain organisms that live in the water may die. If aquatic animals are stressed by large temperature changes they are more likely to become prone to diseases and die. Most aquatic organisms can live within a certain range of water temperatures. Some organisms prefer cooler water, such as trout, while others need warmer conditions, such as carp. As the temperature of a river or lake increases, cool water animals will leave (or die) and warm water animals will replace them. Most organisms cannot survive in temperatures of extreme heat or cold. 7. What is thermal pollution? 8. Why is it unhealthy for a river system? Total Phosphate Just like dissolved oxygen, other dissolved substances can be found in water. One substance is phosphate. A small concentration of phosphates is beneficial for the health of a river. Phosphate is needed for plant and animal growth. However, high levels of phosphates in the river can lead to overgrowth of plants, increased bacterial activity, and decreased dissolved oxygen levels. Excess phosphate is found in living plants and animals, their wastes, and their remains. Algae and other aquatic plants easily take up phosphates. Algae need only a small amount of phosphate to grow. This means that excess phosphate can cause large amounts of algae to grow, called "algal blooms". Soil erosion contributes to the formation of algal blooms by bringing phosphates (in the form of fertilizers and detergents) to the water. 9. Why is too much phosphate unhealthy for the river? Teacher Guide/Learning Set Three TG 207

30 10. What are the sources of phosphate? Nitrate Nitrate is a nutrient needed by all aquatic plants and animals to survive. Some nitrate is good. Excess nutrients such as fertilizer run-off into the river. This causes many plants to grow and eventually die. When they die, bacteria decompose the materials. Because the bacteria use oxygen from the water, the amount of dissolved oxygen available in the water decreases. The decomposition of dead plants and animals and the excretions of living animals release more nitrate into the water system. Sewage is the main source of excess nitrate added to natural waters. Sewage can enter the river through sewage outlet pipes. These outlet pipes are opened during heavy rains to prevent flooding of wastewater treatment plants. Fertilizer and agricultural runoff also contribute to high levels of nitrate. 11.Why is too much nitrates unhealthy for the river? 12.What are the sources of excess nitrates? ph Another factor that influences the health of the river is ph. ph is a measurement of the acidity of water. Liquid substances can be measured and given a value on a scale from A value of 0 is very acidic and 14 is very basic. The ph of neutral water is around 7.0. Industrial waste, agricultural runoff, or drainage from improperly run mining operations can affect ph. Additionally, nitrogen oxides and sulfur dioxide from cars and coal power plants are emitted into the atmosphere to form nitric acid and sulfuric acid. These acids combine with moisture and fall as acid rain. Some aquatic organisms are adapted to a specific ph level (see Figure 10). They may die if the ph of the water changes even slightly. Other aquatic organisms have a wider range and can tolerate a wide range of ph levels. TG 208 Teacher Guide/Learning Set Three

31 Organism 0pH 2pH 4pH 6pH 8pH 10pH 12pH 14pH Bacteria can live from Plants/algae Catfish, carp & some insects Bass and bluegill Snails and clams Many fish and insects Figure 4. ph scale and the tolerance of various aquatic animals to ph levels. 13. Why do we want to know the ph of the water? 14. Use figure 10 to determine the ph range for bacteria, bass and bluegill, and snails and clams. Turbidity How clear the water looks can also help you determine the quality of the water. Turbidity is the measure of the relative clarity of water. Suspended materials such as clay, silt, organic and inorganic matter, and microscopic organisms cause turbid water. The murkier the water, the greater the turbidity. Turbid water decreases the number of organisms that can live in the water. This is because there is less sunlight that can penetrate the water. Also, water temperature increases because suspended particles absorb sunlight, causing oxygen levels to fall (remember, warm water holds less oxygen than colder water). Turbid water may be the result of soil erosion, urban runoff, and bottom sediment disturbances. Bottom sediment disturbances can be caused by boat traffic and abundant bottom feeders (organisms that stay near the bottom of the water when feeding). 16. Why is it important to measure the turbidity of the water? 17. What causes turbid water? Teacher Guide/Learning Set Three TG 209

32 Fecal Coliform Fecal coliform is a bacteria that naturally occurs in the human digestive tract and aids in the digestion of food. Fecal coliform bacteria are found in the feces of humans, other warm-blooded animals such as cattle, and birds. However, where there is too much of this type of bacteria present, there is the potential that harmful pathogens can also be present. Pathogens are small organisms or viruses that cause disease. We measure the amount of fecal coliform bacteria found in rivers because the pathogens are scarce and it would take too long to try and find them. Even though they are scarce, it only takes a small amount to make a person sick. In water, if fecal coliform counts are high, there is a greater chance of pathogens being present. Swimming in waters that have high fecal coliform counts can increase a person's risk of getting sick because pathogens enter the body through the skin, cuts, nose, ears, or mouth. Fecal coliform bacteria can enter a river through run-off or sewage discharge. Some cities have a separate sewer system for sewage and run-off, but other cities have a combined sewer system. In a separate sewer system, sewage from toilets, washers, and sinks flow through a sewer and go to the wastewater treatment plant. Rain and snowmelt from streets flows through a separate sewer and discharges directly into a river without any treatment. In a combined sewer system, sewage and storm runoff both go to a wastewater treatment plant. However, during a heavy rain, storm water may be diverted to a combined sewer overflow system (CSO). If this happens, it may go directly into a river, untreated. To prevent this, some cities build retention basins that hold storm water until the treatment plant can handle it. Without a retention basin, heavy rains can result in high fecal coliform counts downstream from sewage discharge. 18. Why do we measure fecal coliform bacteria to determine the health of a river? 19. What is a combined sewer overflow system? Why are they important? TG 210 Teacher Guide/Learning Set Three

33 Overall Water Quality Ranking Fill in the chart below according to the test results of your group. The "Weight" column tells you how important that test is in determining the quality of the water. To get the overall ranking, multiply the Rank column by the Weight column. Record the result in the Overall Ranking column. For example, if your turbidity test result were 65 JTU, then it would have a rank of 2 (fair). You would then multiply 2 x 0.10 and get an overall rank of The overall Water Quality Index is the sum of the Overall Rank column. Test Test results Rank (A) DO % saturation 0.17 BOD 0.16 Temperature 0.11 Phosphate.011 Nitrate.011 ph 0.10 Turbidity 0.10 Fecal coliform 0.08 Weight (B) Overall rank (A x B) Overall Water Quality Index Overall Water Quality Index Total Water Quality 4.00 Excellent Good Fair Poor 0.99 or less Very poor 20. Write a paragraph describing the overall water quality of the sample that you tested. Teacher Guide/Learning Set Three TG 211

34 TESTING PROCEDURES (Cut, separate or laminate as needed.) Testing for DO Dissolved oxygen needs to be tested at the river to get an accurate reading. The amount of dissolved oxygen in your river will determine what organisms can live there. It will also help you determine the quality of the water in your river. Your teacher will provide the equipment necessary to perform the water quality tests. Materials Test tube 2 dissolved oxygen TesTabs DO color chart 1. Take the temperature of the water sample. 2. Submerge the small tube into the water sample. Carefully remove the bottle from the water sample, keeping the tube full to the top. 3. Drop two Dissolved Oxygen TesTabs into the bottle. Water will overflow when tablets are added. 4. Screw the cap on the tube. More water will overflow as the cap tightens. Make sure no air bubbles are present in the sample. 5. Mix by turning the tube over and over until the tablets have dissolved. This will take about 4 minutes. 6. Wait 5 more minutes for the color to develop. 7. Use the DO color chart to compare the color to the sample. Record the result as ppm Dissolved Oxygen. 8. Locate the temperature of the water sample on the percent saturation chart (fig.3). 9. Locate the dissolved oxygen result of the water sample at the top of the chart. 10. The percent saturation of the water sample is where the temperature row and the dissolved oxygen column intersect. For example, if the temperature of the water is 18 C and the DO content is 4ppm, then the percent saturation is 42%. Record this number in the "Test Results" column in the table on the next page. 11. Use Figure 4 to determine the rank for dissolved oxygen percent saturation. Record this number in column A. In the example above, 42% saturation is fair, and gets a ranking of 2. TG 212 Teacher Guide/Learning Set Three

35 Figure 1: Dissolved Oxygen % Saturation Chart *Calculations based on solubility of oxygen in water at sea level, from Standard Methods for the Examination of Water & Wastewater, 18th edition. Dissolved Oxygen (ppm) Figure 2: Result %Sat %Sat %Sat <50 %Sat Rank 4 (excellent) 3 (good) 2 (fair) 1 (poor) Teacher Guide/Learning Set Three TG 213

36 Testing for BOD Testing for BOD will help you determine the quality of water in the river. This test takes 5 days to perform, so plan ahead. When you take your sample for BOD, remember that the water near the river bottom is where most of the oxygen-demanding organisms are found. So, the best sample is one that is between the surface and the bottom. When you test for BOD, you are trying to determine how much dissolved oxygen in the water sample is used by bacteria. Once you have your sample, you will cover it with aluminum foil and put it in a dark place. This is because you do not want any algae in the water to photosynthesize and produce more oxygen. Putting the sample in a dark place will prevent photosynthesis. In order to complete the BOD test, you will compare the results of this test to the DO test in the previous section. To test for BOD, you will need: 2 Sampling tubes Aluminum foil 4 DO TesTabs DO color chart 1. Submerge the small tube into the water sample. Carefully remove the tube, keeping it full to the top. Cap the tube. 2. Wrap the tube with aluminum foil and store it in a dark place at room temperature for 5 days. 3. Unwrap the tube. Add two Dissolved Oxygen TesTabs to the test tube. 4. Cap the tube. Make sure there are no air bubbles. Invert until tablets have dissolved. Wait 5minutes. 5. Compare the color of the sample to the dissolved oxygen color chart. The difference in the DO level between the uncovered tube (see previous section) and the tube with aluminum foil is the BOD of the water sample. Record the result in the column A. Dissolved Oxygen (with foil) Dissolved Oxygen (uncovered) 6. Look at figure 3 to determine the rank and record it in the "Ranking" column below Result Rank 0 ppm 4 ppm 8 ppm 4 (excellent) 3 (good) 2 (fair) Figure 3: Result 0 ppm 4 ppm 8 ppm Rank 4 (excellent) 3 (good) 2 (fair) TG 214 Teacher Guide/Learning Set Three

37 Testing for Temperature The temperature test measures the change in water temperature at two points. By finding temperature changes along the river, we can determine sources and effects of thermal pollution. Because this test compares the difference between two sites, it is important to match the physical characteristics of the sites (i.e. current stream, depth of the river, etc.) Materials Low range and high range thermometers Low Cost monitoring kit container 1. The two thermometers have an adhesive back. Adhere them to the kit container, 4 inches from the top. The temperature is indicated by a liquid crystal number on the Low Range thermometer and a green display on the High Range thermometer. Low Range C High Range C blue GREEN tan/red 2. Wear protective gloves. At each site, fill the cup to the top. 3. Wait one minute and then read the temperature. Record the temperature as degrees Celsius. 4. Repeat the test approximately 1 km away as soon as possible and record your results. 5. The difference between the temperature at the two sites is the change in temperature. Record this in column A on page Use Figure 4 below to determine the rank and record it in column B. Figure 4: Temperature Change 0-2 C 3-5 C 6-10 C >10 C Rank 4 (excellent) 3 (good) 2 (fair) 1 (poor) Teacher Guide/Learning Set Three TG 215

38 Testing for Phosphate Materials Sampling tube 2 phosphorous (PHOS) TesTabs phosphate color chart 1. Fill the sampling tube to the 20 ml line with the water sample.. 2. Add two Phosphorus (PHOS) TesTabs to the sample. 3. Cap the bottle and mix by inverting until the tablet has dissolved. Bits of material may remain in the sample. 20 ml 4. Wait 5 minutes for the blue color to develop. 5. Compare the color of the sample to the Phosphate color chart. 6. Record the result in the "Reading" column. 7. Look at figure 5 below to determine a rank. Enter this number in column A. Figure 5: Result 1 ppm 2 ppm 4 ppm Figure 8. Rank 4 (excellent) 3 (good) 2 (fair) TG 216 Teacher Guide/Learning Set Three

39 Testing for Nitrate Before you test your water sample, be sure you clean your sampling tube with non-mineral water. Distilled water contains ammonia (NH3) ions that will change the test results. Materials Sampling tube 2 wide range CTA testabs nitrate color chart 1. Fill the cylinder bottle to the 10 ml line with the water sample. 10 ml 2. Add two Nitrate Wide Range CTA TesTabs to the sample. 3. Cap the bottle and mix by inverting until the tablet has dissolved. Bits of material may remain in the sample. 4. Wait 5 minutes for the red color to develop. 5. Compare the color of the sample to the Nitrate color chart. 6. Record the result as ppm Nitrate in the Reading Column 7. Use Figure 6 to determine the rank and record it in column A. Figure 6: Result 5 ppm 20 ppm 40 ppm Rank 2 (fair) 2 (fair) 1 (poor) Teacher Guide/Learning Set Three TG 217

40 Testing for ph Materials Sampling tube Two ph TesTabs ph color sample chart 1. Fill the cylinder bottle to the 20 ml line with the water sample. 20 ml 2. Add two ph TesTabs to the sample. 3. Cap the bottle and mix by inverting until the tablet has dissolved. Bits of material may remain in the sample. 4. Compare the color of the sample to the ph color chart. 5. Record the result in the Reading column. Use Figure 7 to determine the rank. Record the result in column A. Figure 7: Result Rank 1 (poor) 1 (poor) 3 (good) 4 (excellent) 3 (good) 1 (poor) 1 (poor) TG 218 Teacher Guide/Learning Set Three

41 Testing for Turbidity Turbidity can be tested using a simple device called a Secchi disk. A Secchi disk is a black and white disk that is usually lowered into the water to see how far it goes down before it disappears. However, since you are mostly testing shallow rivers, you will collect a water sample using the kit container. Materials Water monitoring kit container Secchi disk icon sticker Turbidity chart 1. Remove the backing from the secchi disk icon sticker. 2. Adhere sticker on the inside bottom of the kit container. Position the sticker slightly off center. 3. Hold the Turbidity Chart on the top edge of the jar. Looking down into the jar, compare the appearance of the secchi disk icon on the bottom of the kit to the chart. Record the result as Turbidity in JTU with your other recorded data. fill ph coliform turbidity Color chart 4. Use figure 8 to determine the rank for the result. Record this in the column A. Test kit Figure 8: Result 0 >0-40 > >100 Rank 4 (excellent) 3 (good) 2 (fair) 1 (poor) Teacher Guide/Learning Set Three TG 219

42 Testing for Fecal Coliform Pathogens are scarce in water, making them difficult to find. So, we measure fecal coliform because there is a strong link between fecal coliform counts and the probability of getting sick from the water. It is important to know the weather conditions on the days prior to taking a fecal coliform measurement. If there was a heavy rainfall, then there may have been excess sewage released into the water and your test results will be high. Materials Sampling tube with tablet 1. Pour the water sample into the large test tube that already contains a tablet until it is filled to the 10ml line. 2. Replace the cap on the test tube. 3. Stand the tube upright, with the tablet flat on the bottom of the tube. 4. Incubate by storing the tube upright, at room temperature, out of direct sunlight, for hours. Store the tubes where the temperature will be constant between 70 to 80 F. Do not disturb, handle, or shake tubes during this period. 5. Compare the appearance of the tube to the picture on the Coliform color chart. Record the result as positive or negative. 6. Use figure 9 to get a rank and record it. Figure 9: Result Negative Positive Rank 3 (good) 1 (poor) Negative Liquid above gel is clear. Gel remains at bottom of tube. Indicator remains red or turns yellow with no gas bubbles. Indicates less than 200 total coliform colonies per 100 ml of water. Positive Many gas bubbles present. Gel rises to surface. Liquid below gel is cloudy. Indicator turns yellow. Indicates more than 200 total coliform colonies per 100 ml of water. TG 220 Teacher Guide/Learning Set Three

43 Lesson 2 Concluding the ph and Fertilizer Investigations OVERVIEW AND OBJECTIVES Learning Objectives Using data from their investigation students will formulate a conclusions to their experiments. Assessment Criteria Conclusions will be based on and supported by data and meet the guidelines for a good conclusion (see below). Purpose Students analyze their data and construct conclusions for the Fertilizer and ph investigations. Class discussions facilitate student reflection concerning the various project activities and how they connect to the driving question. These guided discussions introduce students to the other variables that affect water quality, how these substances might get into the river and their possible environmental effects. PREPARATION Special Considerations If experiments have not shown significant change, add to the computer model first, then re-evaluate experiments. Materials Retrieve experiment - test tube or jars Optional graphing paper Time One fifty-minute period. Teacher Guide/Learning Set Three TG 221

44 INSTRUCTIONAL SEQUENCE INTRODUCING THE LESSON Review with the class the key aspects of the investigation - Purpose -Hypothesis -Procedure Have students retrieve experiment (test tubes or jars). What to expect: Fertilizer The jar with the most fertilizer should show the most growth. This may be measured by increase in the color density, (ie: may be more green) or by the length of the plant. ph As acidity increases (ph decreases from 7-1), the more harmful the effect on plant growth. At ph 6, plants should appear normal (green) ph 4, plant should appear yellowish. ph 2, plant should look very limp and yellow. If this does not happen, stress the importance of multiple testing. CONDUCTING THE LESSON Analyzing Data As a class have students take a look at their data noticing any patterns or trends they can find in their observations. (Optional-Hand out graphing paper) Have students work in groups to graph their data and answer the following questions: - How does the amount of fertilizer (causal, independent variable) affect the growth of the duckweed (dependent variable)? - What evidence in your observations support your statement? -Was your hypothesis supported or not supported? Have students discuss the group questions: -Ask for individual groups to share their interpretation of the data. As a class, discuss findings. - Have groups call on each other to compare results. Conclusion (Suggested Rubric Guidelines) Support the class in composing a proper conclusion. A good conclusion has: (either write on the board or hand out rubric) - A description of the purpose of the investigation. -A statement of your hypothesis. -A statement describing if your hypothesis was supported or not supported by your data. -Evidence (observations and data) which links to either support or disprove your hypothesis. -A statement of how the investigation relates to the driving question. - What you would do to improve the investigation, or what other questions has this investigation caused you to think about? TG 222 Teacher Guide/Learning Set Three

45 Work with the students through the above process to build their conclusion. - Use student observations and probing questions to facilitate the conclusion building process. -If students are having difficulties, post 2 different conclusions: one excellent and one sub par to demonstrate a good conclusion and a not so good conclusion, and have students identify the correct and incorrect aspects in each. CONCLUDING THE LESSON Review with the class the key features of a conclusion. Student volunteers share conclusions. Wait Time Student responses to questions are facilitated by using wait time. After asking a question, wait at least a few seconds before allowing a student to respond, then wait another a few seconds before responding to the student. Class assesses conclusions using conclusion rubrics. Provide student opportunity to revise. HOMEWORK Students work on their ph conclusion for home session. Class offers feedback the next day so students can revise their conclusions. Learning from Assessment Assessment provides students with an opportunity to learn. Display on the classroom wall, as well as provide students with a copy of evaluation criteria (rubric) for completing a conclusion. Students may also be facilitated in developing conclusions by conducting peer assessments and by having opportunity to make alterations, however it is a good idea to first model this concept for students. Teacher Guide/Learning Set Three TG 223

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47 Lesson 3 Expanding the Computer Model OVERVIEW AND OBJECTIVES Learning Objectives Using new concepts generated from experiments and class discussion students will explain the relationships between the new objects and variables. Assessment Criteria New models will include plants as an object. Variables should reflect concepts discussed in class, they may include: nitrates, phosphates, fecal coliform, turbidity and/or dissolved oxygen. PREPARATION Set-up If needed make a reservation for the computer lab. Time One fifty-minute period. Purpose Students use new concepts learned in building relationships with computer models. Teacher Guide/Learning Set Three TG 225

48 INSTRUCTIONAL SEQUENCE INTRODUCING THE LESSON Student volunteers share conclusions from the previous day Class assesses using conclusion rubrics Assign a date for students to complete a final version of their conclusions. Tell the class that we are going to add new objects and variables, such as the concepts we have just discussed in our conclusions, to the computer models. (Review difference between objects and variables, also that an object can have more than one variable.) If groups are struggling in identifying variables try using the classroom driving question board and notecards. One could also use the What happens when it rains? worksheet. If greater support is needed, have groups share a variable or relationship to the class. Strategy might include: students call on a peer to offer a critique of the variable/relationship. CONDUCTING THE LESSON Planning New Variables and Relationships In small groups have students describe some of the objects and variables associated with recent investigations and classroom demonstrations. Monitor student progress. Potential prompts for providing assistance include: - What variables were associated with the ph and fertilizer experiments? - What did these variables affect and how might they get into the river? - What are some new concepts we learned in the past couple of days related to water quality? - What variables could we identify from the dissolved oxygen demonstration? Prompt students to identify the new object that they will be using : plants TG 226 Teacher Guide/Learning Set Three

49 POSSIBLE VARIABLES Object River Plants Variable Dissolved Oxygen Turbidity Total Solids ph Amount of Nitrates Amount of Phosphates Amount of Fecal Coliform Temperature Growth Health Expanding the computer model Once students have planned 3-5 new variables and relationships, allow students an opportunity to build and test these new relationships. Teacher Guide/Learning Set Three TG 227

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51 Lesson 4 Water Testing OVERVIEW AND OBJECTIVES Learning Objectives Using the water quality test kits and equipment, students will become adept at measuring water quality variables. (lab skills). Assessment Criteria Students will be proficient using water quality tests and equipment. Purpose During this lesson, students test the variables they have been studying on river water samples. There are two options for testing river water: 1. Take a trip to your river and conduct water tests the field. 2. Teacher obtains local water samples and students complete water tests in class. (Create a teacher video if feasible.) PREPARATION Special Considerations Read through preparation in the Appendix and familiarize yourself with each test. Make sure you are comfortable with how each test works in order to answer student questions on procedures. Materials 1-5 gallon bucket of river water. (Optional)Video of water sampling. 10 Low Cost Water Quality Monitoring Kits Student Worksheet/Water Testing Time Two fifty minute periods. Working in groups, students perform five water quality tests on water samples from their river. Students perform the tests for nitrates, phosphates, fecal coliform, turbidity, and ph while the teacher performs DO, BOD, and temperature tests at the time of the water sampling fro the river. The water quality of their local river, based on each individual test, is ranked on a scale of excellent to poor (4-1). Teacher Guide/Learning Set Three TG 229

52 INSTRUCTIONAL SEQUENCE Potential supports for making predictions include: Describe and provide students with a rubric for a quality prediction and rationale. Prompt groups to provide reasons for their predictions. Have a few students share predictions and rationale with the class Have students share predictions and rationale with their group members. Based upon this collaboration each group constructs one prediction. Allow groups to revise predictions and rationale based upon class sharing. INTRODUCING THE LESSON Review and discuss with students the variables they have been investigating that affect water quality, prompt them to reflect on their computer models (ie. dissolved oxygen, fecal coliform, nitrates, phosphates, etc.) Inform the students that now that they are familiar with what affects water quality it is time to test their river s water quality. Briefly introduce the final water quality testing methods, which will depend on which water quality test kit you obtain. CONDUCTING THE LESSON Construct a prediction Individually have students review their conclusions from previous direct water quality measuring activities (e.g. River Walk, Is it Drinkable?) Based upon their conclusions from these activities have the students construct a prediction for water quality of the river based upon the chemical tests that they will complete. Setting Up the Task At this point if you are going to the river you ll want to give your students more specific directions as to who will be responsible for what materials, observations, data recording, etc.. Either way, be sure to demonstrate and have students practice the water testing techniques before you go to the river. After the students have completed their predictions, demonstrate in greater detail the testing kit materials and the general procedure to the testing series: nitrates, phosphates, ph, fecal coliform, temperature, dissolved oxygen, BOD, turbidity, and total solids. TG 230 Teacher Guide/Learning Set Three

53 Hand out Student Worksheet/Water Testing Within groups students decide who will perform each test - The name of the person performing the test is placed next to the name of the test on the River Testing packet. - Everyone should have an opportunity to perform at least one test Teacher checks to see if groups have distributed testing roles.(be sure you have enough directions to distribute, make extras if needed) Student testers review their specific test procedure(s). Final Testing The final water quality testing may be substituted by the Rouge River Monitoring Project. See Rouge River Website Teacher determines if groups are ready to test water. Testing the River Water Note: See Teacher Resources section of this guide for special precautions if going to a river site. Working in groups, students perform the series of water quality tests. Teacher walks around room monitoring student activity. Students record data in their investigation packets, journals or on worksheet sheets. CONCLUDING THE LESSON When groups have completed testing, have them clean up. Support students in sharing data. This may be facilitated by using a classroom chart. An example chart may include: - rows for each water quality test - columns for each group to place the results - allow one column for class average Teacher Guide/Learning Set Three TG 231

54 Groups share data and record it on the classroom chart. Have students give a summary of the variable they were testing. Have students copy classroom chart. TEST Group Group Group Class Average DO Fecal Coliform ph BOD Temperature Phosphates Nitrates Turbidity TG 232 Teacher Guide/Learning Set Three

55 Name Home Room Date Learning Set Three Student Worksheet Teacher Version WATER TESTING Hypothesis Reason For Hypothesis Materials A. water sampling jar B. river water sample C.four square edged tube D.two small vials E. four large vials with fecal coliform tablet F. Nitrate tablets G. Phosphates tablets H. DO tablets I. ph Tablets J. small secchi disk K. color comparison card L. procedure pamphlet M. bucket PROCEDURE Read the procedure carefully. If you have any questions about the procedure refer to the procedure pamphlet in the kit. Decide who will perform each test. Place the name of the person performing the test next to the test name. Teacher Guide/Learning Set Three TG 233

56 Collecting your sample 1. Collect the water sample with the water sampling jar. 2. Remove the cap of the sampling jar. 3. Rinse the jar 2-3 times with river water. 4. Hold the container near the bottom and plunge it (opening downward) below the water surface). 5. Turn the submerged container into the current and away from you. 6. Allow the water to flow into the container for 30 seconds. 7. Cap the full container while it is still submerged. Remove it from the river tank immediately. 8. Go back to your seats. Turbidity - Name 1. Fill the jar to the turbidity fill line located on the outside kit label. 2. Hold the Turbidity Chart on the top edge of the jar. Looking down into the jar, compare the appearance of the secchi disk icon in the jar to the chart. 3. Record the result in the data chart (units are JTU) Fecal Coliform - Name 1. Pour the water sample into the large test tube containing a tablet until it is filled to the 10ml line. Don t worry if you overfill or underfill a little. 2. Replace the cap on the test tube. 3. Stand the tube upright, with the tablet flat on the bottom of the tube. 4. Incubate by storing the tube upright, at room temperature, out of direct sunlight for hours. Do not shake disturb or handle the tube during the incubation time. 5. Compare the appearance of the to the picture on the Coliform color chart. Hold the test tube up against the card in the open white space next to the color chart for the test. 6. Record the result as negative or positive in the data chart. Negative Liquid above gel is clear. Gel remains at bottom of tube. Indicator remains red or turns yellow with no gas bubbles. Indicates less than 200 total coliform colonies per 100 ml of water. Positive Many gas bubbles present. Gel rises to surface. Indicator turns yellow. Indicates more than 200 total coliform colonies per 100 ml of water. Right after test, give your vial to your teacher for special disposal. TG 234 Teacher Guide/Learning Set Three

57 Nitrates - Name 1. Fill the square edged test vial to the 5 ml line with the water sample. 2. Add one Nitrate Wide Range TestTab to the vial. 3. Cap and mix by inverting until the tablet has dissolved. Bits of material may remain in the sample. 4. Wait 5 minutes for the red color to develop. 5. Compare the color of the sample to the Nitrate color chart. Hold the test-tube up against the card in the open white space next to the color chart for the test. Phosphates - Name 1. Fill the square edged test vial to the 10 ml line with the water sample. 2. Add one Phosphate Wide Range TestTab to the vial. 3. Cap and mix by inverting until the tablet has dissolved. Bits of material may remain in the sample. 4. Wait 5 minutes for the blue color to develop. 5. Compare the color of the sample to the Nitrate color chart. Hold the test-tube up against the card in the open white space next to the color chart for the test. 6. Record the result in the data chart. ph - Name 1. Fill the square edged test vial to the 10 ml line with the water sample. 2. Add one Phosphate Wide Range TestTab to the vial. 3. Cap and mix by inverting until the tablet has dissolved. Bits of material may remain in the sample. 4. Compare the color of the sample to the Nitrate color chart. Hold the test-tube up against the card in the open white space next to the color chart for the test. 5. Record the result in the data chart. Teacher Guide/Learning Set Three TG 235

58 FINDINGS Data Chart for Group Record your test results in this chart. Use the Ranking Your Results worksheet at the end of this packet to determine the Quality and Ranking. TEST READING QUALITY RANKING DO Fecal Coliform ph BOD Temperature Phosphates Nitrates Turbidity TEST READING (Class Average) RANKING (Class Consensus) DO Fecal Coliform ph BOD Temperature Phosphates Nitrates Turbidity TG 236 Teacher Guide/Learning Set Three

59 DATA ANALYSIS (USE DATA FROM CLASS CONSENSUS) Copy class average Rankings into the chart. Multiply each Ranking by the weighting. Add all the Over-all Ranks to calculate Total. TEST RANKING WEIGHTING OVER-ALL RANK (Rank X Weight) DO Fecal Coliform ph BOD Temperature Phosphates Nitrates Turbidity Over all Water Quality Index Total= OVERALL WATER QUALITY WATER QUALITY Index Total 4.00 Excellent Good Fair Poor 0.99 or less Very Poor Teacher Guide/Learning Set Three TG 237

60 CONCLUSIONS What have you learned? Does your data support your hypothesis? Your conclusion should be at least 2 paragraphs and include: A. A description of the purpose of the investigation. B. A description of the questions you were trying to answer. C. Make a claim that you either support or reject your hypothesis. D. Provide evidence to support your claim: use data that you have interpreted in the experiment. E. Include limitations and or a statement of errors that might have occurred. F. Write your claim clearly: it needs to be a complete thought, and written in precise scientific language. Anyone who picks this up should be able to understand what you did and what you write. G. If any pollution was detected review what you learned about pollution sources from earlier projects activities (nine water quality factors, Stream Table activity, or river walk) and report where the pollution may have come from. TG 238 Teacher Guide/Learning Set Three

61 How can your conclusion be connected to the driving question, what is the water like in our river? Teacher Guide/Learning Set Three TG 239

62 RANKING YOUR RESULTS Look on this chart to convert your results to a water quality rank. Be sure to copy the results onto your data table! FACTOR RESULTS QUALITY RANK Dissolved Oxygen (DO) % Excellent % Good % Fair 2 <50% Poor 1 Biological Oxygen Demand BOD 0 ppm Excellent 4 4 ppm Good 3 8 ppm Fair 2 Coliform Bacteria Negative Good 3 Positive Poor 1 ph 4-5 Poor 1 6 Good 3 7 Excellent 4 8 Good Poor 1 Temperature Change 0-2 degrees Excellent degrees Good degrees Fair 2 >10 degrees Poor 1 Nitrates 5 ppm Fair ppm Poor 1 Phosphates 1 ppm Excellent 4 2 ppm Good 3 3 ppm Fair 2 Turbidity 0 Excellent 4 >0 - <40 Good 3 >40 - <100 Fair 2 TG 240 Teacher Guide/Learning Set Three

63 Lesson 5 Analyzing Test Results and Making Conclusions OVERVIEW AND OBJECTIVES Learning Objectives Using data collected from the water quality tests, students will analyze the classes results and draw conclusions. Assessment Criteria Student s analysis will be based on the class average and will include accurate ranking of each test on a scale of being excellent, 1 being poor. Purpose Student will analyze, interpret and draw conclusion from their data as to the quality of water in their local river. PREPARATION Special Considerations Read through preparation in the Appendix and familiarize yourself with each test. Make sure you are comfortable with how each test works in order to answer student questions on procedures. Materials Student notes, worksheets or observations from water testing. Time One fifty minute period. Teacher Guide/Learning Set Three TG 241

64 INSTRUCTIONAL SEQUENCE INTRODUCING THE LESSON Review the collected data. - Place classroom chart on overhead - Review with students the various tests they conducted - Ask students why they think we have a class average column on the chart. Explain that this helps us to be more scientific ally accurate. For example, you can ask the students if the teacher only picked one student s grades to represent that of the who class, would that be very accurate of all students grades? No, you would take the average of the class. This is why we take an average of the water tests, one group might have not done the procedure correctly or misread the instrument. CONDUCTING THE LESSON Making Meaning of the data collected Place an overhead of the Physical and Chemical Test Ranking Chart up in front of the class (if one is not included make one from the information in your water testing kit). In most kits, these can be found at the end of the booklet describing the procedures for water testing. Student results from yesterdays test are ranked on a quantitative scale of being poor, 4 being excellent. - Model how the students will use their readings to determine the proper ranking number, 1-4. Then have the students work in their groups to rank each test on the scale of 1-4. Teacher checks for student understanding. - Groups share rankings for each test - Peers discuss and class consensus is reached Calculating Overall Water Quality Ranking Explain to the class that each variable we tested affects water quality differently. Some variables are more important or have a larger impact than other variables. Each test has a weighing variable which indicates how important the factor is in determining the overall water quality. For example, some organisms can are better adapted to handle total solids in the water (weighted.08) or levels of nitrates (weighted.10) but can not withstand much drop in dissolved oxygen (weighted.17). Different organisms adapt in different ways to handle various water quality variables. TG 242 Teacher Guide/Learning Set Three

65 We will learn about such organisms in the next session. Teacher places a copy of the weighted water quality chart in front of the class. Class discusses the meaning of the weights. - Look at the weighting variable. - Are they all the same? - Are they different? - How are they different? Test Reading Ranking Weighting Overall Ranking DO 0.17 Fecal Coliform 0.16 ph 0.11 B.O.D 0.11 Temperature 0.11 Phosphates 0.10 Nitrates 0.10 Turbidity If the weighting variable for DO is.17 and the weighting variable for total solids is.07. What does this tell you about how important each variable is in determining water quality? Calculating the overall water quality ranking: (calculators are helpful but not necessary) - Model how each ranking is weighted for example, BOD and temperature. (This can be very confusing for student ) Multiply the ranking value for DO by its weighting variable and record the product. - Have each group do the remaining weighting of each variable. Students should record their results on their sheets. - Have the groups calculate the overall water quality ranking by adding the weighted rankings and recording the result on their data sheets. - Have the students compare the overall water quality ranking to the following scale and record their result. Teacher Guide/Learning Set Three TG 243

66 WATERQUALITY INDEX WATER QUALITY 4.00 Excellent Good Fair Poor 0.99 or less Very Poor Make sure the students wrote down their totals. Explain that what they did is very similar to what scientist do when monitoring the quality or various streams and river. Preparing to Write the Conclusion Review with the students what should be in their conclusion. Key ideas may include: - Review criteria for a quality conclusion - Focus student attention upon the previously posted conclusion rubric - Add one additional criteria to the conclusion: How does our results from this series of water quality tests compare with the results from our previous tests? (River Walk Observation, Is it Drinkable Observation) Conclusion criteria: - Make a claim related to your hypothesis - Provide evidence to support your claim: use data you have collected - Write your claim clearly. It needs to be a complete thought, and written in precise scientific language. Anyone who picks this up should be able to understand what you write. - Students write a statement of error or limitations for their experiment. CONCLUDING THE LESSON Writing Conclusion Have individual students write a conclusion. Have students share conclusions with two to three peers. Peers offers feedback based upon the rubric. Students revise conclusions. HOMEWORK If students have access to computers have them do a web search for stream monitoring sites and have the students compare what they did and their procedures with what they found on various websites. TG 244 Teacher Guide/Learning Set Three

67 Lesson 6 New Relationships With Computer Models OVERVIEW AND OBJECTIVES Learning Objectives Students will identify relationships that include the new concepts related to water quality. PREPARATION Time One fifty-minute period. Assessment Criteria Model s relationships will include objects and variables associated with water testing and classroom investigations and will demonstrate correct relationships. Purpose Students will design new relationships with their computer models utilizing the new objects and variables identified in recent experiments. Teacher Guide/Learning Set Three TG 245

68 INSTRUCTIONAL SEQUENCE INTRODUCING THE LESSON Review Conclusion Student volunteers share conclusions Class assesses using conclusion rubrics Assign a date for students to complete a final version of their conclusions. CONDUCTING THE LESSON Planning New Variables and Relationships Tell the class we are going to add new objects and variables to our computer models. In small groups have students describe some of the objects and variables and their relationships associated with water testing and classroom demonstrations. Monitor student progress. Possible monitoring strategies are: - After approximately 10 minutes have groups share a variable or relationship with the class. Students call on a peer to offer a critique of the variable/relationship. - Have students raise their hands after 2 or 3 variables/ relationships have been identified. Check variables and if they are OK allow students to proceed to the computers and build. Additional supports may include the following line of questioning - What variables were associated with water testing? - What did these variables affect and how might they get into he river? - What are some of the new ideas we learned recently? Tell the students that they might want to use a new object: people and/or animals Students test new relationships Have students test their relationships and be prepared to defend and support their models in a peer discussion. CONCLUDING THE LESSON Have students share their relationships and discuss the new elements they have added. Have peers critique each others new relationships. TG 246 Teacher Guide/Learning Set Three

69 Lesson 7 Bioindicators OVERVIEW AND OBJECTIVES Learning Objectives Using ideas generated in class and possible collecting of organisms, students will describe which macroinvertebrates are indicators of water quality. Assessment Criteria Student descriptions will include the ideas of pollution tolerance and sensitivity, habitat requirements and biodiversity. Purpose During this lesson, students use the biodiversity of aquatic organisms as an additional method to determine water quality in their local river. The collected organisms are identified and sorted by the students. The results are then analyzed and conclusions are made about water quality. Optional Have your class participate in the Science in the City Watershed Investigation and submit their macroinvertebrate information to the program. Information will be available to Science in the City educators this spring. PREPARATION Special Considerations Prepare an aerated water tank in the classroom for keeping live benthics a before collection organisms, make sure there are many hiding places in the tank, some organisms will prey on others. Student permission slips will be needed if going to the river. Teacher will have to decide between taking a sampling trip to the river with the class, or collecting the samples a head of time. Have materials prepared for the option you choose. Have the sorting kits already set up or together before the students get into groups. Read through Macroinvertebrate Identification and Sorting Guide Sheets to familiarize yourself with the process of sorting and ranking. Materials Aquarium tank for housing the collected organisms in the classroom D frame collecting nets, or other dip nets jars or containers to keep organisms in while traveling gloves and goggles waders (optional) Sorting kit, each containing the following: - ice cube trays or 14 petri dishes - spoons, forceps and turkey baster - magnifying glass - gloves and goggles - large shallow light colored pan Student Worksheet/Macroinvertebrate Identification and Sorting Time Two fifty minute periods. Teacher Guide/Learning Set Three TG 247

70 INSTRUCTIONAL SEQUENCE Anchoring Experience Examining the living organisms in their river connects students to the river in their community. Students should reflect back on the observations they made during the river walk, video, and/or virtual tour. Option ONE Taking the students on the sampling trip will bring the students closer to their river. Option TWO Although not as exciting as participating in the sampling, a video of the sampling will bring closer to their river and the activity. Expected student responses Students will most likely respond with answers such as fish and plants. Actually most students will be surprised by the diversity of organisms that live in water because they are not readily observable at a quick glance. The ideas that students will generate for what type of things do organisms need to survive may also be small and simple with answers such as light (for plants), food, places to live, and oxygen. Encourage them to be specific. INTRODUCING THE LESSON Review with the class the previously developed definitions for water quality and some of the water quality testing methods they discussed at the end of the previous session. Inform students that an additional method for testing water quality is doing an investigation using organisms that live in the river as indicators of water quality CONDUCTING THE LESSON Macroinvertebrates Prompt students to brainstorm responses to the following questions. - What types of organisms live in and around the water? - Why would these animals be important? - What do living things need to survive? Introduce the term Macroinvertebrate and explain that this group of bugs is an indicator of water quality. Explain that these bugs, macroinvertebrates play a key role in stream health and and as indicators of water quality because they differ in their ability to tolerate pollution. Some are tolerant of pollution and others are not. Further explain that many macroinvertebrates live along the sides and bottom of streams and rivers. Since each type has a different degree or tolerance for pollution, their presence or absence can be an indication of the quality or health of the river or stream. - Discuss the important role of macroinvertebrates at the base of the food chain for other organisms in the river ecosystems, and that they make up a good part of the biodiversity in rivers -Discuss with the class the concepts of "biodiversity" and why it is important for not only rivers but all natural areas to have bio diversity. Student Investigation Ask your students to think back to their river walk. - Did they see any signs of biodiversity? Ask for examples? - Could we tell by looking at the river if there were any macroinvertebrates? - How might we find out if there are any in our river? TG 248 Teacher Guide/Learning Set Three

71 Prompt the students to respond that they need to do an investigation. Inform the students that they will be conducting an investigation of the macroinvertebrates in their river. Have students make hypothesis and predictions regarding what biodiversity they think they will find. Preparing to Collect the Organisms Before the organisms are collected the teacher must decide how the collection is to be conducted. There are two options 1) the teacher does the collection or 2) the students do the collecting. Describe for the class the several different sampling locations (river bottom, bank, in vegetation, and under rocks). Ask students why several different locations are sampled (to obtain a larger and more diverse sample. If students are collecting the organisms then a description of the collecting procedures needs to be completed. Additionally, you will need to go over safety rules for conduct at the river. Review with the class the collection procedures, transportation and containers for the organisms. Assign roles and responsibility ties for the students while they are on their collection trip. Describe and/or demonstrate the collection equipment. The D-frame net is a simple way of collecting benthic macroinvertebrates. The D- frame net is design so that the flat area at the front of the net can be placed at the bottom of the river reducing the loss of organisms underneath the net. You can use this net to collect samples from the bottom of the river as well as along the banks of the river and in vegetation. WEARING GLOVES AT ALL TIMES Discuss the proper procedure for handling the macroinveterbrates from the net to the containers. Possible Alterations One possible extension to this activity is to have students compare the different sampling locations. - Have the students make predictions about the organisms from these different locations - Will they be similar or different? Why? - Will they have special adaptations? What kinds? - Have students record predictions and rationale. Biodiversity refers to the range of organisms present in a given location. When pollution changes environmental conditions, some organisms can not survive. A few organisms can tolerate a range of conditions. Therefore the more different types of organisms that are found, the less pollution there is. (Optional if students are not doing the collecting) Teacher Guide/Learning Set Three TG 249

72 Contextualization If organisms were collected by the teacher, show a video tape or other method to indicate where the organisms came from. Teachers Collecting the Macroinvertebrates Bottom of River If you have waders then this activity is best done in the water. If you do not have waders then you can still get some sampling done from the bank of the river. Either from within the river or from the bank, place the net at the downstream side of the sampling area with the opening facing upstream. Hold the net perpendicular to the flow and as close to the bottom of the river as possible depending on your position. Hold the net for a short period of time. After good flow has moved through the net. Take the net out and place what ever you collected in a large bucket with some water in it. Repeat the sampling until you have collected a large enough sample for your classes with which to work. Methods of Collecting There are multiple methods of collecting benthic macroinvertebrates. For other methods of collection, see the Field Manual for Water Quality Monitoring by GREEN. Gloves and Goggles If students will be participating on the collection of the organisms, students should wear gloves and goggles. If you are able to go into the river and have some assistance, sample again with the net. Hold the net close to the bottom of the river as you did before, but this time have your partner stand three feet in front of the net and twist their feet into the bottom of the river. This action will free sediment from the river bottom and dislodge more macro invertebrates. Bank of River Walk along the bank of the river. Choose an area along the bank and simply place the net along the side of the bank with the opening of the net facing upstream. Rub the net along the side of the bank disturbing any sediment. Hold the net for a short period of time. After good flow has moved through the net. Take the net out and place whatever you collected in a large bucket with some water in it. Repeat the sampling until you have collected a large enough sample for your classes with which to work.. In Vegetation Choose an area that has a large amount of vegetation. Place the net in the water by the vegetation so that the opening faces upstream. Firmly rub/brush the vegetation with the net, disturbing any organisms that may be hiding or attached to the vegetation. Move the net up and down and side to side. Hold the net for a short period of time. After good flow has moved through the net. Take the net out and place whatever you collected in a large bucket with some water in it. TG 250 Teacher Guide/Learning Set Three

73 Repeat the sampling until you have collected a large enough sample for your classes to work with. Under Rocks Wearing gloves, pick up any stones or rocks greater than 2" in diameter. Rub it to remove any organisms that may be present and place them in the collecting bucket. Upon Return Upon returning from the collection, place the organisms into a previously prepared river tank. Habitat Comparison Option: (Optional- Several tanks may be utilized if the teacher wishes to have separate tanks for different collection locations. This option allows for students to make comparisons between the organisms of different locations) Setting up the class Break students into groups. Provide each group with an Identification and Sorting guide and a sorting kit, and a large pan with Macroinvertebrates. Teacher models the process first, followed by the students. Using their identification and Sorting guides students count each different type of organism in each group (one, two, and three). Students place a check mark next to each type of macroinvertebrate found. Teacher monitors the progress of the groups. Checking Student Results and Sharing Data When most groups have completed the activity, the teacher leads the class in a brief sharing of their data. Teacher uses overhead or large chart and asks groups to identify one organism they found. Ask other groups if anyone else counted the organism. If agreement, mark on class chart. Repeat steps with the next group or organism. Teacher Guide/Learning Set Three TG 251

74 Sorting To facilitate the identification and sorting,you can use two methods: Write the name of each type of organism at the bottom of each compartment of the tray so as students sort they can also identify them one by one. CONCLUDING THE LESSON Ask students what are some of the limitations to this type of investigation method. - If the students struggle to come up with limitations use prompts such as: - Do you think the area where we collected samples is an accurate representation of the entire stream? -How was the weather in the last few days, could things be washed away? -What if we didn t sample a location that had suitable habitat? Have students clean up and return samples to their proper tanks. USE CAUTION Identification and Sorting Biting Organisms Caution students that some organisms may pinch or bite. They should be handled with spoons or tweezers. Biotic Index for Sample Is an index that indicates water quality based on the pollution tolerance of macroinvertebrates Wearing goggles will keep river water from being splashed into student s eyes. Wearing Gloves will protect students from any pathogens in the water. Students should wash their hands with a disinfectant soap after handling the Organisms. TG 252 Teacher Guide/Learning Set Three

75 Name Home Room Date Learning Set Three Student Worksheet Teacher Version MACROINVERTEBRATE SORTING AND IDENTIFICATION Teacher Guide/Learning Set Three TG 253

76 MACROINVERTEBRATE SORTING AND IDENTIFICATION TG 254 Teacher Guide/Learning Set Three

77 MACROINVERTEBRATE SORTING AND IDENTIFICATION Teacher Guide/Learning Set Three TG 255

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79 Lesson 8 What Do Organisms Tell Us? OVERVIEW AND OBJECTIVES Learning Objectives Using data from collecting macroinvertebrates or teacher given data, students will analyze and make a conclusion about the quality off water in their river. Assessment Criteria Conclusions will be based on the good conclusion rubric utilized throughout the unit, and will include the data from the macroinvertebrate collection. PREPARATION Set-up See EPA Website on Bioindicators Materials Refer to Lesson 7 for this Student Worksheet/Macroinvertebrate Sorting and Identification Time One fifty minute period. Purpose Students use the results from the collection of macro invertebrates or teacher data re analyzed an conclusions are made about water quality. Teacher Guide/Learning Set Three TG 257