Overview
Lesson 1: Introduction to Relationships between Humans and the Environment
Lesson 2: Berries in the Ecosystem
Lesson 3: Traditional Ecological Knowledge
Lesson 4: Historic versus Contemporary Landscapes
Lesson 5: Responsibility of Society
Lesson 2, Day 1
Standards
LIFE SCIENCE
- SC.CM.LS.03.03—Explain how the balance of resources will change with the introduction or loss of a new species within an ecosystem.
CD Segments to Play
Background
Suggested Strategies
Activities
1. Discuss
The basic components of an ecosystem include nutrients (found within in the earth), water, oxygen and the biological components. Energy (from the sun) is the vital component that fuels the ecosystem. A very basic and easy to understand model of an ecosystem can be illustrated with a simple potted plant. Have the students think about the five components (nutrients, water, oxygen, living organisms, energy) and how they relate to the potted plant. Make 5 columns on the chalkboard labeled with the five components; have the students write the same table, labeled Ecosystem Energy Flow.
Ask the students how each of the other components relate to the potted plant.
Help the students to make the connections as illustrated in the following table.
| Nutrients | Water | Oxygen | Living Organisms | Energy |
| X | X | X | Leaf | X |
| X | X | Roots | X | |
| X | Decomposers (fungi and bacteria) | X | ||
| X | X | Chlorophyll (pigment in leaves) | X |
Explain to the class that plants are autotrophs, meaning they produce their own food. The plant leaf uses the nutrients, water and carbon dioxide to make carbohydrates (a carbohydrate is stored chemical energy), while it is the chlorophyll that traps the energy for photosynthesis to occur. Photosynthesis is what converts the oxygen to carbon dioxide. The plant uses the nutrients to convert some of the carbohydrates into other necessary nutrients such as fats and proteins. Plants are the only autotrophs that exist and therefore the plants are a vital component of any ecosystem since this is the only way that energy enters into the ecosystem.
Ask the students what would happen if there were only autotrophs in a given ecosystem?
By removing the decomposers from this simple model, autotrophs would eventually use all available nutrients and the plant kingdom would end. The decomposers break down the dead leaves and other plant materials and in doing so, return nutrients to the soil.
Ask the students where the decomposers get their energy?
“Breaking down” the dead leaves essentially means eating the material (extracting necessary energy from plant material) and excreting the waste product (nutrients back into soil).
Ask the students how berries fit into this model?
Energy is the key to all ecosystems. Ultimately the sun is where all energy derives from. As living organisms eat food (just like the decomposer ate the dead leaves and other plant material) they gain the energy necessary to live. A calorie is simply a measurement of energy. The energy flow in an ecosystem is the flow of energy from one organism to the next. The Law of Conservation of Energy is the first law of thermodynamics and states that energy can neither be created nor destroyed; it can only be transformed from one form to another. The second law of thermodynamics states that when energy is transformed, some energy is lost. All organisms in an ecosystem are connected in a food chain or food web. There are several trophic levels; a trophic level describes how far an organism is from the initial energy source which is the plants who are considered primary producers (of energy). The second trophic level is the primary consumers or the herbivores. Tertiary consumers are the omnivores who eat plants and animals. The fourth level are the consumers who are carnivores eating smaller carnivores, etc. The fifth level is the top carnivores (no natural predator).
2. Research
Have the students break into their research groups; have each student create a food web using huckleberries; and then have each research group combine their food webs with each other. Remind the students of the various components of a huckleberry shrub and how many different kinds of wildlife (and humans) may depend upon it. Encourage the students to consider not only the edible factor of the berries, but to look at the whole picture including seed dispersal, and the attraction of a given animal to the berries, providing a food source for its prey. Have this food web added to the Berry Portfolio.
Lesson 2, Day 2
Standards
ENGLISH LANGUAGE ARTS
- EL.CM.SL.05—Analyze the occasion and the interests of the audience, and choose effective verbal techniques and language.
- EL.CM.SL.10—Formulate judgments about ideas under discussion, and support those judgments with convincing evidence.
CD Segments to Play
Background
As was discussed in the Wisdom of the Elders segment, Mount Hood is a favored berry picking spot and forest lands are abundant berry sites for the Confederated Tribes of Warm Springs. Prior to the European arrival, berries were a significant food source and controlled burns were a common land management tool.
In the late 1800s burning was outlawed by the newly formed Oregon government. Controlled burns were a way to keep a forested area from reaching its final climax vegetative state.
There are several stages of development in the plant world; this is called succession. Primary succession is the beginnings of plant life. Beginning with the simplest plant life which grows on rocks, volcano overflow (hardened lava) plant development occurs. The first kinds of plants are lichens which through their waste products (acid) begins breaking down the rock which allows mosses to come in. Over time, the lichens and mosses contribute acids and organic materials to allow ferns and some seed plants to form (the seeds often find their way into cracks in rocks (from weathering processes and the decaying organic materials and acids). Soils begin forming and soon other plants begin coming in (depending upon the type ecosystem, forestland, prairies, tropical regions, etc.). Different forms of plant life appear based upon the given ecosystem which is based upon climate, geography, elevation, etc. One type of plant dominates a given area. In a forested area such as is found in the Pacific Northwest, coniferous trees (such as Douglas fir, cedar, and pine trees) dominate.
In a forested area, commonly the overstory is dominated by the larger trees. The understory are composed of shade tolerant trees and shrubs such as rhododendrons, on the edges (the area between the shaded and non-shaded areas) many shrubs are found including berries, Oregon grape and many other types of shrubs. Deciduous trees like maple, hazel, dogwood, alder, cascara, etc. can be found both in the understory, the edges and sometimes in meadows depending upon their shade tolerance. In the open meadows are wild flowers, wild strawberries, and many different native grasses, A forested area that completes its cycle of growth will end up being dominated by the larger trees which provide too much shade for many plant species. An area that reaches its final state is said to have reached climax (this takes many hundreds of years of no disturbance). Nature, however causes events such as lighting strikes causing fires, wind events knocking over trees and allowing shade into the area, heavy rains cause landslides, erosion, etc. Additionally insect infestations cause widespread devastation to the dominant trees, and volcano eruptions can entirely wipe out an area. A lava flow would take an area back to primary succession where the lichens must first begin breaking down the hardened lava into areas where the other plants can come in. Other less devastating events will take a forested area back to secondary succession.
Secondary succession refers to the vegetation that first emerges with soil present, similar to the plants that are found within the edges (the area between the overstory and the meadows.) Along with the shrubs (berries are good examples) seeds are dispersed by maple, hazel, dogwood, etc. The plants, shrubs, trees, etc. are always competing for light, water and nutrients. As secondary succession progresses, the deciduous trees (trees that lose their leaves in the fall) begin growing and cause shade to stunt the growth of the types of shrubs normally found only on the edges. As succession continues, the coniferous trees outgrow and outshade the deciduous trees resulting in a climax vegetative state again. One final factor to consider in forest succession is the introduction of non-native plants to an area. Native plants progress through succession in a cyclical manner; as events unfold, plants respond to the environment. When non-native plants such as scotch broom, evergreen and Himalaya blackberries are introduced to an area, these plants disrupt the natural successional pattern and overtake an area.
Native blackberries are very rare to find because the more aggressive and larger Himalaya and evergreens overtake their natural environment, plus these non-native species (also called exotic species) are able to overtake the area because they have no natural predators (wildlife dependent upon them as a food source) and anytime there are no natural predators, the species rather it be plant or animal overpopulates and disrupts the natural processes.
Suggested Strategies
Activities
1. Discuss
Ask the students if anyone knows why controlled burns were so important?
Ask: Have you ever walked in a forested area? What kinds of things did you notice?
