SMILE Lesson Plan Deyan Crow, Hayley Clark, and Sean Kelley Title: Diggin’ for Data! Connection to Theme: Students will have the opportunity to investigate soil and the macroinvertebrates inhabiting it in two different habitats, a meadow and a forest. This will give students the opportunity to explore how these biotic (macroinvertebrates) and abiotic (soil) factors interact as well as compare how they differ between habitats. Key Points/Objectives: 1. Students will be able to differentiate between major taxa of macroinvertebrates commonly found in soil (annelids plus four clades of arthropods: insects, arachnids, myriapods, and crustaceans) 2. Students will know how to safely and accurately use science equipment to measure abiotic factors (light intensity and soil moisture, temperature, and pH) 3. Students will be able to record and make connections between quantitative data about species diversity and soil quality 4. Students will be capable of explaining the differences of abiotic and biotic factors in an ecosystem and how they affect each other Site: Meadow and forest downhill of meadow Science Tests: • Invertebrate identification by taxa (with opportunities for students to delve into genus/species identification for “bonus points” if they are interested) • Population survey of different macroinvertebrate taxa (sorted into Annelids and Arthropods: Insects, Arachnids, Myriapods, and Crustaceans) • Soil Moisture • Soil Temperature • Light intensity • Soil pH Background: Soil and Abiotic Features In Rhode Island soils have a naturally low pH between 5-6, but pH can vary in different soils from being basic or acidic. So, because the pH can vary so should the biota that live in that soil!
Volumetric Water Content (VMC) is the amount of water that is present in the soil. This is important because biota like plants need there to be enough water in the soil to absorb the water and nutrients that are in the water. Having a low VMC could mean a habitat unsuitable for plant or insect life. Soil temperature is another important abiotic factor to test for insects, like humans are sensitive to temperature. So, if the soil temperature is too hot or too cold it could affect the insects living there. These are all tests of some abiotic features in soil that could directly influence what biotic organisms live in that soil or could potentially live in that soil. Invertebrate Taxonomy and Identification Annelids are a phylum of invertebrates also known as segmented worms. They have soft, segmented bodies and no legs. Earthworms are an example of an annelid commonly found in the soil. Read more about annelids: http://www.eplantscience.com/index/general_zoology/segmented_worms.php Arthropods are a phylum of invertebrates with an exoskeleton and jointed legs. We will be learning about four different types of arthropods: hexapods, arachnids, myriapods, and crustaceans. All hexapods have six legs. In fact, the word hexapod even means “six feet”! Most hexapods are insects, such as beetles and ants, but there are a few non-insect hexapods, such as springtails. Arachnids, such as spiders, harvestmen, mites and ticks, have eight legs. Myriapods, which include centipedes and millipedes, have lots of legs and very long, segmented bodies! Most crustaceans, such as crabs and shrimp, live in the water, but some isopods (a type of crustacean with 14 legs) live in the soil, instead. We call these terrestrial (land-dwelling) isopods pill bugs or rollie pollies. Read more about arthropod taxonomy: http://eol.org/pages/164/overview https://www.dlia.org/basic-arthropod-taxonomy Materials: • Variety of Invertebrate Field Guides and Info Sheets (at least 12) • Shovels (2) • Quadrats (2) • Clear plastic tubs—big enough for 1 shovel full of soil (6) • Bug jars/boxes (at least 12) • Magnifying glasses (6) • Spoons (12) • Rulers (6) • pH strips (6) • DI water (6) • Water content probe (6)
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Soil thermometer (6) Densiometer (6) 100-200 mL beaker (2) Stirring rods—to stir and DI water (2)
Lesson Cycle Hook (5 min): 1. Students will play On the Bus, Off the Bus to review the concept of biotic and abiotic factors and generate curiosity about forest and meadow habitats. They will be presented with a series of factors they might find in forest or meadow ecosystems and step forward (on the bus) if they think those are biotic and backwards (off the bus) if they think they are abiotic. Intro to New Material (15 min): 1. Introduce different invertebrate taxa and what soil conditions they live in by looking at an illustrated handout together. 2. Introduce the basics of soil quality and why they are important. Ask students to make a few predictions about what animals would live in certain soil conditions. 3. We will practice these by playing “Categories” on the walk to the field site. (Instructor will name a category and students will name animals that fit that category. The last student to successfully name an animal in the category given wins that round. Category examples could include: Arthropods, Insects, Invertebrates that like moist soil, Invertebrates that like low pH, etc.) Guided and Independent Practice (40 min): Abiotic Factors (20 min): 1. Upon arriving at the site, students will split into two large groups: The Wiggly Worms and the Rollie Pollie Pillbugs. The Wiggly Worms will meet in the meadow and the Rollie Pollie Pillbugs will meet downhill in the nearby forest. 2. At each site, a student volunteer will measure light intensity with guidance from an instructor. (Students will record this in their data books.) 3. The instructor will lay down a quadrat, shovel out a sample of the earth in that spot into a tub, and demonstrate each of the three soil quality tests (temperature, pH, and moisture). 4. Students at each site will split into three groups, each containing roughly 4 students: Purple Team, Blue Team, and Green Team. In each group, one student will shovel soil into their tub and the remaining three will each do one soil test. (Students will record their group’s results in their data books.) 5. After measuring abiotic factors, each group will spend the next few minutes observing and taking notes about the surrounding plants and habitat. In their data books, they will have the opportunity to sketch the habitat they are in and answer questions such as "How big are the plants you see? How long do you think they live? How fast do you think they grow? What type of animals do you think might live in a habitat with plants like these?"
Biotic Factors (20 min): 1. Instructors at each site will introduce the population survey and scavenger hunt and walk students through the start of the population survey by having each group identify the first invertebrate in their bucket and record it with a tally mark in the table in their data books. (Students can choose to either release the animal at the site where they dug it up or keep it in a bug box for further investigation, but remind them not to put it back in their main tub to avoid double-counting.) 2. Students will then complete the rest of their population surveys (and the scavenger hunt, which will prompt students to continue thinking about plants and other habitat features) independently, though instructors will be available to answer questions and help with reading field guides as needed. Closing (20 min): Small Group Debrief (10 min): 1. The meadow team and forest team will reconvene and present their findings (and anything interesting they found during the scavenger hunt). First, each group of 4 will be matched with a group from the other site (i.e. Purple Wiggly Worms meet with Purple Rollie Pollie Pillbugs to form a group of 8 students) and an adult facilitator to discuss their findings and fill in discussion questions in their data books. Whole Group Debrief (10 min): 2. At the end, the three discussion groups will get together and share their findings. Assessment: Students will demonstrate their ability to measure abiotic factors by recording their light intensity and soil quality measurements in their data books. They will then demonstrate their ability to differentiate between invertebrate taxa and record quantitative data by keeping tally in their data books of the invertebrates they find. Finally, they will answer open-ended questions in their data books to demonstrate their ability to interpret the data they collected regarding biotic and abiotic ecological factors.