The big picture of Carbon in a forest community By Dale Moore, Engadine Consolidated Schools

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1 The big picture of Carbon in a forest community By Dale Moore, Engadine Consolidated Schools Target Grade: 11 th grade Environmental Science Class Subject: Forestry Unit Overview: The carbon cycle is a key concept in understanding forest ecology. As forests are now being considered as a biofuel source then the students need to understand how carbon and carbon products move through an ecosystem. Biodiversity, carbon cycle, photosynthesis, cellular respiration, and carbon amount are topics that need to be connected in a real world sense. The students have been exposed to photosynthesis, cellular respiration, and the carbon cycle in Biology, and Physical Science. Now in the Environmental Science class students will have the opportunities to connect the topics as they take measurements in the school's forest. This unit would follow topics like geology, weather, soil, and biogeochemical cycles. The Forestry unit is where this lesson would be included. The goals of the lesson would be that students would be able to compare various forest types in terms of what trees are present, how the carbon cycles between trees and animals, how a greater biodiversity equals a more healthy forest, and how much carbon is stored in the trees. Sources Consulted: Jaeger,J.: GIS, Geographic Information System. Future Fuels from Forests Teacher Institute Michigan Tech University. The making of the tree I.D. card is a modification of the "vocab card" taught in the GIS lecture by J. Jaeger. Janowiak, M.: "Biofuels and Carbon Sequestration" power point lecture. Future Fuels from Forests Teacher Institute Michigan Tech University, Houghton. The power point will be used as a means to direct the students to think about the various options in biofuels. Some of the questions used prior to the power point will be answered in a more visual media, therefore, helping to clarify the concepts. Janowiak, M.: "The Carbon in Trees" activity from Future Fuels from Forests Teacher Institute Michigan Tech University. This activity is used as the measuring tool for determining the biomass and carbon mass for the trees on the school forest. Shonnard, D.: "Technology for Processing Woody Biomass to Biofuels" powerpoint: Future Fuels from Forests Teacher Institute Michigan Tech University. Dr. Shonnard's power point will be used to introduce the process being developed for the turning of woody biomass into cellulosic ethanol. The final slide will be helpful in teaching the students without them getting bogged down in the chemistry. Ter-Mikaelian, M., Korzukhin, M.: "Biomass equations for sixty-five North American tree species": Forest Ecology and Management 97 (1997). There are equations for trees in this source that were not included in "The Carbon in Trees" activity by Janowiak. By including the equations, the students will get a more accurate calculation of the biomass and carbon amount for the trees at the school forest. Learning Objectives A. The student will be able to compare various forest types in terms of what trees are present and evaluate how a greater biodiversity equals a more healthy forest,. This will be accomplished by the making of tree identification cards, a tree identification test and comparing the number of tree species from different locations. The skills needed will be the ability to differentiate between tree types based on characteristics of the tree. The recognition of tree types will help students evaluate the biodiversity (Michigan HSSCE B3.4B). 1

2 B. The student will recognize the equations for photosynthesis and respiration including the products and reactants of each. Students will demonstrate this knowledge in the form of written equations. Their knowledge of the carbon cycling between trees and animals will be shown by the production of a poster that shows how carbon and biomass are cycled between plants and animals. The students will use labeled drawings to depict the organisms and arrows to show the path the carbon and biomass are moving (Michigan HSSCE B3.1C, B3.1D, B3.3b). C. The student will describe renewable and nonrenewable sources of energy and compare the effects on the environment (costs and benefits) by reviewing power point shows on carbon sequestering and ethanol production. Students will answer questions and describing renewable, nonrenewable, carbon sequestration and ethanol production (Michigan HSSCE E2.4A). D. The student will determine how much carbon and biomass is stored in the trees. The student will need to measure tree diameters using a diameter tape and measure the area of the forest studied using a tape measure. Students will develop data collection charts (Michigan HSSCE B1.1C). Michigan High School Science Content Expectation (HSSCE) Biology B1.1C Conduct scientific investigations using appropriate tools and techniques (e.g., selecting an instrument that measures the desired quantity-length, volume, weight, time interval, temperature-with the appropriate level of precision). B3.1C Recognize the equations for photosynthesis and respiration and identify the reactants and products for both. B3.1D Explain how living organisms gain and use mass through the processes of photosynthesis and respiration. B3.3b Describe environmental processes (e.g., the carbon and nitrogen cycles) and their role in processing matter crucial for sustaining life. B3.4B Recognize and describe that a great diversity of species increases the chance that at least some living organisms will survive in the face of cataclysmic changes in the environment. Earth Science E2.4A Describe renewable and nonrenewable sources of energy for human consumption (electricity, fuels), compare their effects on the environment, and include overall costs and benefits. 2

3 Environmental Science Day 1 class starter Topic: Forestry Name Date Assignment: Create a poster that shows how carbon and biomass are cycled between plants and animals. Use labeled drawings to depict the organisms and arrows to show the path the carbon and biomass are moving. Activity: 1. Answer the following questions: a. What does mean? b. What does diversity mean? c. Put the two definitions together and create a definition for biodiversity. 2. Class discussion: type of plant cultures a. Mono means one type of plant. b. Poly means several types of plants. c. Natural means plant types that have grown with minimal human influence. d. Consider the following plant communities and label each as either mono, poly or natural. 1. Red pine plantation 2. Front section of school forest 3. The marsh at the corner of U.S. 2 and M Vegetable garden 5. The lawn around a house e. Many of these areas you have been around. Think about the varieties of plants in each area and make a guess as to variety of non-plant organisms in that area. Do this by making a list of organisms you would expect to find in each. 1. Red pine plantation 2. Front section of school forest 3. The marsh at the corner of U.S. 2 and M Vegetable garden 5. The lawn around a house f. What connection do you see between the number of plant varieties compared to variety of other organisms (biodiversity)? 3. Carbon cycle and biomass as fuel a. In the area below write in word, chemical formula or picture form what a tree needs to live and what it gives off as waste (photosynthesis). 3

4 b. In the area below write in word, chemical formula or picture form what an animal needs to live and what it gives off as waste (cellular respiration). c. What does the tree make with the carbon dioxide that is not a waste product? d. Animals need what is made in "question c." What do they need it for? e. Identify the reactants and products for each of the processes above. Reactants Products Photosynthesis Cellular respiration f. Biomass is the mass of living or once living organisms. Much of the mass is in the carbon atom. Living or once living organisms are made of many carbon atoms attached together to make long chains of carbon, hydrogen, and oxygen. The molecules are called organic molecules and they contain a lot of useable energy. g. What product of the cellular respiration does a tree get its mass from? h. We will light a wooden match as an example of a tree burning (very similar to cellular respiration). What is released into the air? i. How would you explain the use of a tree for fuel as renewable fuel? j. Some view biomass as a potential fuel with a closed carbon cycle? What do you think this means? (You may need to review "e") k. Why would burning fossil fuels like gasoline not be considered a closed carbon cycle? 4

5 Environmental Science Name Day 2 Date Class starter Topic: Forestry Assignment: Turn in today's class starter at the end of the hour. Turn in your flow chart on cellulosic ethanol tomorrow. Activity: 1. Answer the following questions: a. List one plant community that would represent a monoculture. b. List one plant community that would represent a natural system. c. Choose the one from above with the greatest plant biodiversity and explain why that translates into a greater animal biodiversity. 2. To use or not to use woody biomass as fuel. a. First choose which of the following will take more human input, fertilizer and fuel to grow, a 40 acre field of corn or a 40 acre woods of aspen trees. b. What type of equipment is needed to harvest corn? c. What type of equipment is needed to harvest aspen? d. What type of fuel is made with corn? What type of fuel is made with woody biomass? 3. View "Biofuels and Carbon Sequestration" power point by Maria Janowiak. a. After watching the power point answer this question: What determines whether one type of biofuel is better at capturing (sequestering) carbon dioxide? 4. View "Technology for Processing Woody Biomass to Biofuels" power point by David Shonnard. a. After watching the power point create a flow chart of how cellulosic ethanol is processed. b. As needed we will review the power point. 5

6 Environmental Science Name Day 3 Date Class starter Topic: Forestry Assignment: Tree identification (I.D.) cards due on the day of the test. Tree I.D. test on Monday. Field trip to the school forest Wednesday - Monday Activity: 1. Bring a notepad or clipboard, paper and a pencil. 2. Load bus. 3. Discussion topic while on the bus: why is it important to identify trees when there are no leaves? What can be used to identify a tree in the winter time? 4. While we walk the trails of the school forest, write down the name of each new tree encountered on your note pad. Be sure to include identifying characteristics of the tree. Tree types on the school forest: Jack pine, white birch, quaking aspen, big toothed aspen, white pine, ironwood, white ash, balsam fir, hard (sugar) maple, soft (red) maple, yellow birch, white spruce, Russian ( or Autumn) olive, American beech, basswood, pin cherry, beaked hazelnut and June berry 5. Return to the bus. On the trip back we will review your data and discuss the assignment. Assignment: Tree I.D. cards a. On one side of the card write the name of the tree. b. On the other side write the name of the tree in the upper right corner. Draw some identification characteristic in the middle of the card. Below and around the picture complete the description of the tree. c. Until Monday you may make additions and modifications to your cards. 6

7 Environmental Science Name Day 4 Date Class starter Topic: Forestry Assignment: Tree identification (I.D.) cards due on the day of the test. Tree I.D. test on Monday. Field trip to the school forest Thursday - Monday Activity: 1. Bring a notepad or clipboard, paper and a pencil and tree I.D. cards. The instructor will supply the diameter tapes, tape measure, calculators and the conversion factors needed to calculate the biomass and carbon content of the trees in the sample plots. 2. Load bus. 3. Discussion topic while on the bus: How to determining the biomass of trees and the amount of carbon in the trees for a sample plot. a. The class will conduct the measurements on a 1/10 of an acre plots. This will be measured using a circle with a radius of 37.2 feet. b. Measure only trees with a diameter of 12.7 cm (5 inches) or greater. c. We do not have the conversion factors for ironwood, Russian olive, beaked hazel nut, and June berry so do not measure those trees, but include them on the data chart as trees present but not measured. d. Read the instructions for the "The Carbon in Trees" activity. This instruction is for one tree. e. Your group will need to make a data chart that shows the tree type and diameter for each tree measured. Include trees present but not measure on the chart also (you only need to name these). f. When all of the trees are measured add up the total diameter for each species. g. Use the total diameter for each species to calculate the biomass and carbon per tree species as instructed on the "The Carbon in Trees" activity. h. Add all the biomass totals for each species to get the total biomass of the site. i. Add all the carbon mass totals for each species to get the total carbon mass of the site. j. There will be 4 groups assigned to different areas of the school forest. Each area will be different forest type. 4. Unload the bus and the instructor will demonstrate the measurements and calculation for one tree before the groups are sent off to their sample plots. 5. Groups measure their trees and return to the bus to complete calculations. 6. Return to school. 7

8 Environmental Science Name Day 5 Date Class starter Topic: Forestry Assignment: Tree identification (I.D.) cards due on the day of the test. Tree I.D. test on Monday. Biomass and carbon calculations and this class starter due on Monday. Field trip to the school forest Friday - Monday Activity: 1. Bring a notepad or clipboard, paper work from yesterday and today's class starter. The calculators will be provided. 2. Load bus. 3. Discussion topic while on the bus: a. Finish calculations for biomass and carbon content. 4. Unload the bus. 5. Discussion and review. Complete numbers 2-5 on your notepad a. The class will visit each of the 4 sites and complete the following: 1. Review tree types. 2. Discuss the biodiversity of the site in terms of plant species and animals present. At the last site evaluate which site would have the best biodiversity and why. 3. Create a carbon cycle diagram using trees and animals from each site. Label the diagram with the appropriate site location. 4. Discuss the results of the biomass and carbon calculations. Compare the results of each site by making a chart indicating the site, total biomass and total carbon mass. Compare this to the results of the biodiversity evaluation looking for a pattern in the data. 5. Explain which type of forest, based on the data collected and the class discussion, would produce the most biofuel. 8

9 Environmental Science Name Day 6 Date Class starter Topic: Forestry Assignment: Tree identification (I.D.) cards due today. Tree I.D. test today. Biomass and carbon calculations, notepads and the class starters from Thursday and Friday are due today. Field trip to the school forest today. Activity: 1. Bring a notepad. 2. Load bus. 3. Tree I.D. test a. Write your name and date on the front page. b. On the second page write the numbers 1-18 vertically on the page. c. When the class is shown a tree write the name of the tree next to the corresponding number. d. To minimize cheating keep the top sheet over your answers. 4. As you load the bus hand your notepads to the instructor. 9

10 Unit Assessment: A. Each class starter contains questions and/or activities that the students are to complete. The class starters also contain the various assignments to be used as assessment tools. Day 1: Create a poster that shows how carbon and biomass is cycled between plants and animals. Use labeled drawings to depict the organisms and arrows to show the path the carbon and biomass are moving. Day 2: Turn in today's class starter at the end of the hour. Turn in your flow chart on cellulosic ethanol tomorrow. Day 3 and 4: Tree identification (I.D.) cards due on the day of the test. Tree I.D. test on Monday. Day 5: Tree identification (I.D.) cards due on the day of the test. Tree I.D. test on Monday. Biomass and carbon calculations and this class starter due on Monday. Day 6: Tree identification (I.D.) cards due today. Tree I.D. test today. Biomass and carbon calculations, notepads and the class starters from Thursday and Friday are due today. 10

11 Activity: The Carbon in Trees Description: Recent interest in the use of forests for carbon sequestration and bioenergy require knowledge about the amount of carbon stored in a tree or forest. For this activity, you will estimate the amount of carbon stored in a nearby or favorite tree. Objectives: Measure tree diameter; calculate biomass and carbon mass Materials Needed: Tree(s); Diameter tape and/or tape measure; Calculator and/or spreadsheet software; Pencil; Allometric equation for tree species Instructions: Step 1: Measure Diameter If using a tape measure, measure the circumference of the tree at breast height (4.5 feet off the ground; see figure). If necessary, convert this value to cm. Then, using the tree circumference, calculate the diameter. Circumference: cm Diameter: cm Wrap tape measure around tree 4.5 ft above the ground. On a leaning tree, make sure the tape is perpendicular to the trunk. OR: If using a diameter tape, the tree is measured the same way but it is not necessary to calculate diameter since the tape already does that for you. If necessary, convert this value to cm. Diameter: cm Step 2: Calculate biomass for whole tree. To calculate tree biomass, we use a standard allometric equation of the form M=aD b where M is aboveground tree biomass (dry weight; kg), D is the diameter at breast height (cm), and a and b are species specific coefficients. Locate the coefficients for the species of tree that you have in the table and calculate tree biomass (M). Tree Species: Biomass (M): kg Step 3: Determine carbon content Since carbon is the major building block for life, a tree contains large portion of carbon (about half of its biomass). To determine much carbon is in your tree: Multiply biomass (M) by for hardwood trees. Multiply biomass (M) by for softwood trees. Carbon content: kg C Multiply by 2.2 to convert to lbs. Carbon content: lb C Species a b Ash white Aspen quaking Aspen big tooth Balsam fir Basswood Beech Eastern hemlock Northern white cedar Red maple Red oak Red pine Sugar maple White birch White oak White pine Yellow birch Jack pine White spruce Pin cherry a how by Maria Janowiak, Northern Institute of Applied Science, Michigan Technological University 11

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