Is All This Burning Necessary? (Part 1/4)
Lesson 1 of 4
Objective: Students will conduct a two week study to determine fires role in maintaining a healthy prairie.
In today's lesson, students start a short term field study in which they determine the rate of green-up in a tract of native prairie adjoining our school campus. Ecology is best learned by doing. Therefore, I try to get my students outside in the field as much as possible so they can observe firsthand the interactions of abiotic and biotic factors in an ecosystem. Here is an overview of what students will learn today. This is day one of a multiple day lesson. The other lessons can be found at these links (Part 2, Part 3, and Part 4).
Take students to the site for the field study and ask them to sit quietly for six minutes. During the first minute, students should listen quietly and take notes about the types of sounds they hear. Students should record their findings in their lab notebook. For the next two minutes, students should describe what they see at the site. They should record their descriptions in their lab notebook. Students should record the types of vegetation and animals they see. Finally, in the final three minutes, students should make a sketch of the site and label that sketch with the date and any particular features of the site that stand out.
Setting Up the Field Study
For this portion of the lesson, each student group will need the following equipment:
- 1m^2 quadrat
- tent stakes
- metal weighing trays
- metric ruler
- handheld computer
- 2 temperature probes
- CO2 probe
- O2 probe
- soil moisture probe
- digital camera
- GPS probe
- white index card
Assign study areas randomly throughout the field site. (Note: I make sure that study areas are close enough that I can observe all students, but far enough apart that we are able to sample the entire watershed.) Students should first place their quadrat in their study area and secure it to the ground with tent stakes. Use metal weighing trays to mark the corners of the quadrat so that it will be more easily found on subsequent days.
Students should take their initial measurements using the sensors. All data should be taken within their quadrat. In addition to the sensor data, students should take a picture of the site and sky overhead using a digital camera. (Note: We use our cell phones in the split screen mode so that the images will be tied together.) Use these field study protocols with students to explain how data should be collected.
As a class, take a picture of the entire study site from two angles for later comparison at the end of the study.
Before class begins, create a Google Drive spreadsheet. Share the spreadsheet, with each of the student groups so that they will be able to input data. (Note: I have students create a gmail address at the beginning of the year so that we can share data through class spreadsheet. If school policy does not allow for this strategy, use this spreadsheet.)
Have the class return to the classroom. Student groups should input their data into the class spreadsheet.
Using this powerpoint, explain to the student how researchers conduct Long Term Ecological Research (LTER) through field studies. This will help student gain a better understanding of the methods that ecologists use to better understand the interactions between the biotic and abiotic factors within an ecosystem. It will also serve an introduction to what students will see on their field trip to the site.
Give students small copies of the graphs (Precipitation, Temperature, Fire interval study, Big Bluestem Study, and Water quality research) from each study to include in their lab notebook. While explaining the types of studies conducted at the LTER site, ask students the following questions:
- What was studied?
- What were the primary findings from the study?
- How long was the study conducted?
- What other questions might be asked due to the study's findings?
Have students write a trend for each of the graphs and make a list of additional questions that might be asked due to these study's findings. (Note: I have my students take these questions with them when we visit the LTER site as they will have to question some of the researchers.)
(Note: At the end of the two-week field study, we visit a local LTER site so students can compare the results of their short term research with professionals. We do this as part of a Schoolyard Science Program.)
Hand out field work rubric to students. Explain to students that they will be graded on several tasks. Summarize to students the expectations that scientists would have of their field technicians. Students should take careful accurate data. They should make sure that all of their images are in focus and have a proper scale in them. They should record detailed observations of the weather. Students should add all data to the shared class data sheet. Students should also describe the amount of plant growth within the quadrat. Ask them to complete a self-evaluation of their work today.