Lesson 5a: EXAMINING THE RIVER DATA

Overview:

Students visited various sites on the river. They gathered data about the river’s temperature, pH, oxygen levels, current, and transparency. They also collected plant and water samples and photos of living organisms. They conducted stream walks at the various sites. Now they need to study their data to see what they can learn from them. What conclusions can they make about the river’s health? Is it a good place for plants and animals to live?

Focus:  

What can we learn from the field trip data?

Learning Objectives:

Students will be able to:

•     share data and record it on a chart
•     compare the data and use them to draw conclusions about the river’s health
•     discuss what might be done to improve the river’s health.

Materials:

•     river data
•     river notebooks
•     clipboards
•     pencils
•     copies of the data recording sheet for each team or student
•     the recording sheet drawn on a poster or copied onto a transparency or displayed on a screen

Procedure:

1. Have students join you at the board, screen, or other meeting place. Team members should sit together with clipboards, pencils, and copies of the data they gathered at the river.

2. Pass out copies of the Lamprey River Data Recording Sheet to each team or student.

3. Display the same recording sheet on the screen, overhead, whiteboard, or poster.

4. Ask students to help you fill in the data for air and water temperatures for both Fahrenheit and Celsius readings on the large chart. Different groups might have different readings. Gather all results and record them on the screen, transparency, or poster. Have students decide which reading should be used for each site. (The one that occurs most often or the one in the middle.) You want only one reading for each site, so circle the one you’re using or cross out the other ones. Students should record the selected readings on their data sheets.

Discussion (Air and Water Temperatures):

a. What do you notice about the air temperatures for each site? Why might they be the same or different? (They stay the same because it’s a cloudy day or they increase because the sun heats the ground which heats the air as the day goes on, or they got cooler because the sun wasn’t shining in the afternoon, etc.)

b. Why did some groups have different readings? (Thermometer or reading wasn’t accurate.)  

c. What do you notice about the water temperatures at each site? (The temperature is about the same at each site or sites with shallow water might be slightly warmer.) Why? (Water temperature doesn’t change quickly. Many days of warm or cold temperatures are needed for water temperature to change. If the water is shallow, the temperature might change more quickly because there is less water to heat or cool. A large body of water might be colder or warmer because there is more water to heat or cool, so the temperature changes slowly.)

d. Would animals like these water temperatures? (Compare the recorded temperatures to what the second column says animals need.)

e. What can be done to make the water temperatures cooler? (Create more shade by allowing bushes and trees to grow along the river, let the water flow freely, prevent storm water from a hot parking lot from flowing into the river.)

d. Compare the air and water temperatures. What do you notice? (It depends on the weather and the season.)

5. Ask students to help you fill in the data for oxygen levels at each site on the large chart. Different groups might have different readings. Gather all results and record them on the screen, transparency or poster. Have your students decide which reading should be used for each site. (The one that occurs most often or the one in the middle.) You want only one reading for each site, so circle the one you’re using or cross out the other ones. Students should record the selected readings on their data sheets in the correct box.

Discussion (Dissolved Oxygen Levels):

a. What do these data tell about the river? Is there enough oxygen in the river for animals? (The second column tells them what animals need.)

b. Why is there more oxygen at Mary Blair Park? (The water here is turbulent due to rocks and the increased current and this results in more oxygen in the water.)

c. Why is there less oxygen at Northwood? (The site has no current, slope, or rocks to cause turbulence.)

d. How does oxygen gas get into the water? (Water plants give off oxygen, oxygen is dissolved into the water at the surface, turbulence stirs oxygen into the water.)

e. What can be done to increase the dissolved oxygen levels in the river? (Allow the river to flow freely. Keep the river shaded by trees and shrubs so that the water cannot absorb so much heat from the sun. Make sure plants can grow there.)

f. Has our community done anything to keep dissolved oxygen levels high?

6. Ask students to help you fill in the data for pH readings on the large chart. Different groups might have different readings. Gather all results and record them on the screen, transparency, or poster. Have students decide which reading should be used for each site. (The one that occurs most often or the one in the middle.) You want only one reading for each site, so circle the one you’re using or cross out the other ones. Students should record the selected readings on their data sheets.

Discussion (pH levels):

a. What do you notice about the pH levels?

b. Can animals survive with these pH levels?

c. What can be done to reduce the acidity of the water? (Reduce air pollution, filter the water that runs into the river, reduce water pollution, encourage landowners to allow plants to grow on the banks of the river, stop developing the land along the river.)

d. Has our community done anything to reduce the acidity (raise the pH) of the water?

7. Ask students to help you fill in the data for current/speed readings on the large chart. Different groups might have different readings. Gather all results and record them on the screen, transparency, or poster. Have students decide which reading should be used for each site. (The one that occurs most often or the one in the middle.) You want only one reading for each site, so circle the one you’re using or cross out the other ones. Students should record the selected readings on their data sheets.

8. Multiply the 20 meter time for each site by 5. Record the 100 meter time for each site. Have students record the results on their charts.

9. Divide 100 meters by the 100 meter time to figure out the current speed at each site. (Example: 2 meters per minute or 10 meters per minute)

Discussion (Current or Speed):

a. What do you notice about the current or speed for each site? (There’s no current at Northwood. Why?  It’s a pond that doesn’t have a current. The current is faster at Mary Blair Park. Why? The river moves from a higher elevation to a lower elevation and makes the current increase. Gravity pulls the water down over the rocks. The current was heading upriver at Heron Point, so the current was slow there. Why? It was high tide and the tide was pushing the water upriver. Or, there was some current at Heron Point, because the tide was going out.)

b. Would plants and animals like the different current speeds? (Yes, some plants and animals like water with no current and some plants and animals can survive a strong current. Some even need a strong current.)

c. Is the Lamprey River a good place for plants and animals? Why? (Yes, because it has a variety of currents.)

10. Ask students to help you fill in the data for water transparency readings on the large chart. Different groups might have different readings. Gather all results and record them on the screen, transparency, or poster. Have students decide which reading should be used for each site. (The one that occurs most often or the one in the middle.) You want only one reading for each site, so circle the one you’re using or cross out the other ones. Students should record the selected readings on their data sheets.

Discussion (transparency):

a. What do you notice about the transparency at the different sites? (It was less transparent at Heron Point. The tide stirs the water and mixes mud into the water making it less transparent. You could see the bottom at Mary Blair Park, because the water is moving fast and staying clearer. Or, you couldn’t see the bottom, because rain washed lots of debris into the water.)

b. Is the Lamprey River transparent enough for plants and animals? (Yes, because the sunlight is able to reach down into the water. No, the river wasn’t very transparent. We can’t tell because it just rained so much. We’d need to take more readings at other times.)

Data Recording Sheet                                date _________________

 

 

test group names	what animals need	Northwood State Park	Mary Blair Park	Heron Point
temperature     Fahrenheit	water <  75*F  (best < 55*F)	water air
temperature      Celsius	water < 24* C (best < 13*C)	water air
dissolved oxygen	at least 4 to 5 ppm
pH	5.5 to 7.5
current speed time for the apple to travel 10 meters	xxxxxxxxx
current speed time for the apple to travel 100 meters	xxxxxxxxxx
current speed = distance divided by time	a variety of current speeds
transparency    bottom *	the deeper the transparency the better