Forests of the Living Dead

Lesson Content

• Lesson Plan Template:

  General Lesson Plan

• Learning Objectives: What should students know and be able to do as a result of this lesson?

  
  
  • Discuss the importance of decomposition in a forest ecosystem.
  • Describe how the study described in the text is being used to support conservation efforts in forest ecosystems.
  • Cite specific and relevant textual evidence to support analysis of the text.
  • Determine the meaning of selected academic and domain-specific words in the text.
  • Determine the central ideas of the text.
  • Construct a written response that clearly establishes a main point(s), contains relevant textual evidence to support the main point, utilizes transitions to maintain flow, effectively uses domain-specific vocabulary, and provides an appropriate conclusion.

   

• Prior Knowledge: What prior knowledge should students have for this lesson?

  
  

  For science:

  • Students should have an understanding of the flow of energy in an ecosystem and the placement of decomposers in the food web. This site titled "Food Chain," by National Geographic, explains this information.
  • Students should be familiar with forest ecosystems in terms of the abiotic (nonliving) and biotic (living) factors found there. The different forest biomes and ecosystems can be reviewed using this Blue Planet website.
  • Students should have knowledge of bacteria and fungi and how they breakdown and recycle the nutrients in an ecosystem. This website provides a very thorough discussion of the process of decomposition and the organisms involved as well as specific information on decomposition in forest ecosystems.
  • Students should be familiar with the carbon cycle. This is one of the most well known biogeochemical cycles and students should have a working knowledge of its components. A review of this diagram should be sufficient.

  For literacy:

  • Students should have prior experience utilizing various vocabulary strategies to determine the meaning of unknown words in a text. For this lesson, prior experience in using context clues to determine the meaning of words in a text would be beneficial, as would use of word parts and dictionary skills.
  • Students should understand the term "central idea" and be able to distinguish central ideas from key details.
  • Students should be aware of text features that can help them locate and learn information when reading a text. The text features in this National Science Foundation article include: title, subtitle, headings, and one photograph with a caption.
  • Based on the rubric provided with this lesson, students should be able to respond to a writing prompt in a clear, organized manner that includes use of an introduction to establish the main point(s), a body paragraph(s) that support the main point(s) and includes relevant and specific textual evidence, and a conclusion or concluding statement that supports the main point(s).
  • Students should have some awareness that use of transition words or phrases can help a piece of writing flow smoothly from one point or idea to the next. This site provides transitions teachers might provide.

   

• Guiding Questions: What are the guiding questions for this lesson?

  
  
  1. What role do decomposers play in an ecosystem?
     • "Decomposers" such as fungi and bacteria play a vital role in the normal functioning of an ecosystem. As organisms die, it is the job of decomposers to break down the organic matter and recycle those nutrients back into the soil.
  2. How has the data from this study changed views of the importance of the decomposition process in ecosystems?
     • The research has shown that dead wood in a forest provides a wide range of ecological functions for the ecosystem. The dead and rotting wood provides a habitat for many species from insects to birds, can act as seedbed for other plants, and can be involved in stream habitat restoration projects. As a result, the practice of removing dead wood from a forest is changing. Loggers are now leaving downed trees in the forest, and entire management plans discuss the harm that can result when dead or rotting wood is removed.

   

• Teaching Phase: How will the teacher present the concept or skill to students?

  
  
  1. Begin the lesson by showing this brief video of fruits and vegetables decomposing, titled "Fruit and Vegetable Decomposition, Time-Lapse" (1:36, uploaded by YouTube userwebiocosm). Ask the students to get into groups and brainstorm how and what is happening.
     • Expected responses: the fruits and vegetables are breaking down, they are rotting, they are decomposing
  2. Ask students what causes the food to "rot" or decompose.
     • Expected responses: damage to the fruit, bacteria, other microorganisms such as fungi
  3. Ask students why the decomposition process and the decomposers involved are important in an ecosystem.
     • Expected responses: when organisms die they need to be broken down, the process is a component of food webs, decomposition allows nutrients to be recycled
  4. Show the students this food web. Ask:
     • What does a food web show? (Transfer of energy in an ecosystem)
     • What are the producers in this food web? (Oak trees, pine trees)
     • What organisms act as consumers? (Any animal that is feeding)
  5. Ask students: what do all of these organisms have in common?
     • Expected response: all living organisms in an ecosystem are eventually broken down and recycled by decomposers
  6. Show this video by the Harvard Museum of Natural History titled "Decomposing Fungi" (1:48).
  7. Tell students they will be reading an article from the National Science Foundation that describes a study conducted by scientists studying the decomposition process in forests. The lead scientist, Mark Harmon, is known as "Dr. Death" because of his research in forest mortality. His findings have changed the way management plans are being implemented for forest ecosystems.

   

• Guided Practice: What activities or exercises will the students complete with teacher guidance?

  
  
  1. Pass out to each student a copy of the article titled "Morticulture: Forests of the Living Dead" or make it available to students electronically.
  2. For discussion purposes, the teacher may want to have students number each paragraph of the article. If using an electronic copy of the article, students can use a PDF mark-up tool (several tools are available as free downloads).
  3. Provide each student with a note-taking guide. Have students complete this guide during or after their first reading of the article. Make sure to provide print or online dictionaries for students to use for the vocabulary section. Students can work individually, in pairs, or in small groups.
     • Based on the needs and skills of the students, teachers can decrease the number of academic or domain-specific vocabulary students will define on the note-taking guide.
     • For academic vocabulary, students will likely be able to use a variety of vocabulary strategies to define the meaning of the words (e.g., context clues, word parts, dictionary skills). For domain-specific (in other words, subject-specific) vocabulary, students will typically need to draw on prior knowledge and use a dictionary to define the words
       • Verdant (Paragraph 1): Students may be familiar with the root word for verdant if they speak French or Spanish, as vert and verde mean green in these languages. They also may be able to use the context clue as it describes plants.
       • Mortality (Paragraph 2): Students should determine the meaning of the word based on the context clue of describing Dr. Harmon as "Dr. Death" and then describing his interest in forest mortality.
       • Terrestrial (Paragraph 13): Students should be able to determine the meaning of the word based on the context clues found within the sentence it is used. It is used as an adjective to describe different types of species and their habitat. The word aquatic is also used, so students might be able to determine they are discussing species found on and in land and water.
       • Channels (Paragraph 16): If students are not familiar with the term channel in reference to waterways, they should use a dictionary to determine the meaning of the word. They need to look at definitions that are for the noun usage. They should substitute definitions into the sentence and see which fits best. In the paragraph the terms stream and salmon are used, so this should help with context.

  How will you check for student understanding? (Formative Assessment):

  1. Teachers can check students' understanding by collecting students' completed note-taking guide, checking their work, providing written feedback, and possibly grading the assignment. Or, teachers can have students share their responses and the teacher can provide verbal corrective feedback, allowing students to make corrections to their work during the discussion.
  2. Teachers can use the sample answer key provided at the end of the note-taking guide to help them assess students' answers.
  3. For discussion of students' answers to the defined vocabulary words, teachers are encouraged to not only ask students to explain the meaning they determined for a word, but the strategy they used to arrive at that meaning. This will allow the teacher to give alternative suggestions as to how the student could have arrived at the correct meaning of the word.

  Common errors or misconceptions to anticipate and how to respond:

  • Make sure students understand the differences between detrivores and decomposers. This page from the Green Energy site does an excellent job explaining the difference. The teacher may choose to show the information on an overhead for the class to see.
  • Some students believe if a population in a food web is disturbed, there will be little or no effect on populations that are not within the linear sequence in the food web. Any component within a food web can have an effect of the stability of the ecosystem. Decomposers work at every level within a food web.

   

• Independent Practice: What activities or exercises will students complete to reinforce the concepts and skills developed in the lesson?

  
  

  Provide each student with a copy of the text-dependent questions to complete. Students should be reminded to continually refer back to the text and to use relevant and specific evidence from the text to support their answers.

  Formative assessment can come in the form of the following:

  • Teachers can check students' understanding by collecting students' answers to the text-dependent questions, checking their work, providing written feedback, and maybe grading the assignment. Or, teachers can have students share out their responses and the teacher can provide verbal corrective feedback, allowing students to make corrections to their work during the discussion.
  • Teachers can use the sample answer key provided at the end of the text-dependent questions to assess students' answers.

  Common errors/misconceptions to anticipate and how to respond: Please see the answer key for the text-dependent questions.

   

• Closure: How will the teacher assist students in organizing the knowledge gained in the lesson?

  
  

  For literacy:

  1. Before students complete the writing assignment for the summative assessment, review the responses to the text-dependent questions completed earlier by the students. Make sure the misconceptions are corrected and the key points (as found in the sample answer key) are discussed.
  2. After students' written responses have been graded and returned with feedback, teachers might wish to use the sample response, provided at the end of the text-dependent questions, with the class. Students who are struggling writers can benefit greatly from seeing a well-organized, detailed written response. The teacher can show the sample response on an overhead or with anLCD projector and discuss some of the following:
     • How the topic is introduced in the opening sentences of the introductory paragraph; have students identify the main point of the piece. Brainstorm with students other ways the writer could have opened the piece.
     • Have students examine each of the body paragraphs and explain how each supports the main point of the piece.
     • Have students identify where the writer effectively uses textual evidence from the article for support of his or her points.
     • Have students identify the use of transition words or phrases that make the ideas flow.
     • Ask students to identify where domain-specific vocabulary is used accurately and effectively.
     • Have students read the final paragraph to see how the writer wrapped up the piece and connected back to the main point established in the introduction.

  For science:

  Have students read the following article from the Smithsonian: "Forests Around Chernobyl Aren't Decaying Properly."

  Using knowledge gained from the lesson and the information found in the Smithsonian article, have students respond to the following question: "What findings from this study have scientists concerned about the forest ecosystems of Chernobyl?"

  Sample answer: It has been over thirty years since the Chernobyl nuclear plant exploded, yet the impact on the environment is still being felt by the organisms living there. It comes as no surprise to scientists that plants and animals still have signs of radiation poisoning. Around the epicenter of the blast, birds have been discovered with smaller brains, there are fewer trees, and there are fewer insects than you would expect to see in a stable ecosystem. However, what has taken scientists by surprise is the effect the explosion has had on the decomposers in the area.

  An essential element in every ecosystem is the process of decomposition. Normally organisms such as bacteria, fungus, and insects are involved in the breaking down of decaying matter and returning the nutrients back to the soil. As scientists began observing the ecosystem within the blast area, they realized there was a lot of leaf litter and trees that had fallen, but had not begun the process of decay.

  To determine exactly what was occurring with the decomposition process, a team decided to run field tests to record the amount of time it took for leaves to decay. They stuffed over 600 mesh bags with either oak, maple, birch, or pine leaves, making sure there were no insects in the bags. They lined some of the bags with panty-hose as well to prevent insects from getting into the leaves over the course of the experiment. The scientists scattered the bags across various sites that had experienced different amounts of radiation. The bags were left out for approximately a year to study the process that normally should have occurred: the breakdown of the organic matter.

  The results showed that in areas where no radiation was present, most of the material had broken down. In areas where there was radiation, a majority of the organic material remained. Both insects and the bacteria and fungus played a large role in the decay process, but it was determined that fungi and bacteria were most important for breaking down the leaf litter on the top of the soil. The role of decay is an essential part of a stable ecosystem. As organisms die, the nutrients need to be returned to the soil for the plants in the area. If the plants are not receiving the nutrients they need, other components of the ecosystem will be affected also. As long as the decomposers are affected by the radiation, the areas surrounding Chernobyl will have a difficult recovery.

   

• Summative Assessment

  
  
  1. Students will individually respond to the writing prompt. If using the attached rubric to assess students' work, they should be directed to respond with a multi-paragraph response, with a clear introduction, body section, and conclusion. They can refer back to the text as they construct their response.
  2. Provide students with a copy of the rubric and go over it with them so they will know how their written responses will be assessed.
  3. Go over the writing prompt with students and make sure students understand what the prompt is asking them to address:
     • Using evidence from the text, discuss how the unique research conducted by Dr. Mark Harmon has changed environmental practices concerning dead wood in forests. How has his research benefited forest ecosystems?
  4. Teachers will use the rubric to assess students' written responses.

   

• Formative Assessment

  
  

  Specific suggestions for conducting Formative Assessment can be found in the Guided Practice and Independent Practice phases of the lesson where it says, "How will you check for student understanding?"

   

• Feedback to Students

  
  

  Specific suggestions for conducting Feedback to Students can be found in the Guided Practice and Independent Practice phases of the lesson where it says, "How will you check for student understanding?"