Province: British Columbia

Learning Objectives

Students will:
-define the terms abiotic and biotic
-identify interactions between abiotic and biotic components in ecosystems
-relate climate and abiotic components of ecosystems
-understand impact of changing abiotic factors upon biotic components of ecosystems

Teaching Process

1. Define biotic and abiotic

-Divide the class into groups of approximately four students. Give each group a set of biotic/abiotic component cards. Make these by cutting the A/B Categories worksheet (list of abiotic and biotic components) into separate pieces, one item per “card”.
-Ask the students to categorize the items on the cards. Do not mention or introduce the terms “biotic” or “abiotic” at this time. Direct the students to sort the items into two groups; they can put aside any items that do not fit into their categories. You may wish to give the students a short time limit to ensure this process is fairly quick and lively while encouraging discussion.
-Alternatively, give the full worksheet to each group and ask them to sort by putting an “A” or “B” next to each item to represent the category they belong to.
-Ask the groups to name and define each of the two categories.
-Invite each group to share the names of the categories they created, making a list on the board.
-Debrief, guiding the discussion to focus on the identified categories of biotic/abiotic (i.e., living/non-living). Acknowledge the groups that came up with reasonable alternate categories. Provide formal definitions of biotic and abiotic (see above Introduction).

2. Challenge student understanding

-Ask the students, “What cards, if any were difficult to categorize?” Discuss why.
-Direct each group to find 3 examples in the classroom, school, and/or schoolyard that are difficult to categorize as biotic or abiotic.
-Have each group challenge another group to categorize their example. Discuss as a whole class, refining and clarifying the definitions.
-Alternatively, have ready an assortment of items for the groups to try to categorize. These can include:
-Items that were once living things or are comprised of organic matter, e.g., tree stump, blood, fossil, a fruit or vegetable, pickle
-Items that are a mix of abiotic and biotic components, e.g., soil sample, water from a puddle or tidepool, detritus, vegetable beginning to decompose due to bacteria and/or mould
-Organic or inorganic compounds, e.g., sugar (carbohydrate), salt (NaCl), metal object, diamond or graphite, glass.
-Review with whole class, discussing why each item is abiotic, biotic or mix of both.

3. Relate abiotic factors to climate

-Ask each group to list all the abiotic components they can that relate to climate. Review weather versus climate if necessary (see Resources).
-Have groups share their list with the whole class and create a master list on the chalkboard. Discuss why each abiotic component is included or not.
Master list should include: sunlight (specifically visible light from the sun), temperature, water (specifically humidity and precipitation), air pressure and wind.

4. Define ecosystem

-Provide a definition of ecosystem (e.g., the relationships and interactions amongst all the biotic and abiotic components of the environment).
-Ask the class: How do abiotic components affect biotic components within an ecosystem? Explore some possible connections with the students (e.g., limiting factors and population distribution and/or population size due to changing fecundity and mortality rates; changes in community composition over one abiotic component such as elevation or slope direction).
-How do biotic components influence abiotic components? Explore connections (e.g., utilize resources; trees affect humidity level and temperature under their canopy; organisms can trample, burrow into, cause erosion of substrate, etc.)
-Review biotic-biotic relationships (e.g., predator-prey relationships, symbiosis, etc.) and abiotic-abiotic interactions (e.g., weathering of rock due to wind, precipitation, water flow; reflection/absorption of sunlight by water in various phases, etc.)

5. Create an ecosystem relationship web

-In an open area, have students stand and form a circle. Give each student one of the cards from the A/B Categories worksheet.
-Start with a student holding one of the abiotic components (ideally sunlight). Ask the student to locate another component, either biotic or abiotic, that they know interacts with their own component. The student holds the end of the string while carefully passing or tossing the ball of string to the other student with the interacting component. The passing student states the interaction or relationship between the two components. The student with the ball of string now repeats the above steps.
-Continue identifying interactions while passing the ball of string until all students are connected in the string web. Assist students as necessary to find an interaction and/or elaborate on the provided response. Students can repeat interactions already identified or include a new biotic or abiotic component.
-Debrief the process. Ask the students “Is this activity representative of an ecosystem? How? Why not? (e.g., It is like an ecosystem in that there are many interactions between abiotic and biotic components; actual ecosystems have more components with more complex interactions).
-Identify the components in the ecosystem web that may limit the population size or distribution of species (i.e., what are the limiting factors). Though they are species specific, typical limiting factors include the availability of food, water, or shelter, predation and disease pressure.

6. Ecosystems and climate change

-To introduce the potential impact of climate change on ecosystems, ask one of the students with an abiotic component that is influenced by climate (e.g. part of the climate system) to pull on their string. What do people in the web notice? What might this represent? (e.g., a reasonable response could be “an increase in summer temperatures or precipitation rate due changes in the climate”). Add another abiotic factor pulling on the web.
-Now ask a biotic component to drop their string. What do people notice? Ask those that felt a difference in the tension of their string to also drop their string. What could this represent? (e.g., a possible answer could be “a loss of one population affecting the food web).
-Debrief by asking students to reflect on how a change in climate may affect various components in an ecosystem.
Tip: At the end of the activity, ask all the students to lay the string on the floor, then request one student to start winding up the string, starting with the end that was connected last into the web.

Teachers Notes

*Find "Concept Map Rubric" and "A/B Categories Worksheet" in the attached lesson plan link.

Assessment/Evaluation

1. Ask students to design an experiment to examine the affect of climate related abiotic factors on biotic factors (e.g., amount of water or sunlight available to growing plants). Have students conduct the experiment and provide a full lab report, including a discussion of the potential impact of climate change on ecosystems. Look for evidence that students understand the terms abiotic and biotic, and how some abiotic components are climate factors.

2. In groups, give students 20 minutes to quickly sketch an ecosystem of their choice that highlights 5 biotic and 5 abiotic components. Identify 3 possible interactions between abiotic and biotic components.

3. Ask students to create a concept map illustrating the connections between abiotic and biotic components in an ecosystem and a change in the climate. Use the Concept Map Rubric to assess student’s concept maps.