Exploration - The Catch of the Chesapeake Bay (Creating a Model)

This part of the lesson consists of a brief introduction about what students are supposed to do with the hands-on materials provided to them, and  the overall goal which is a reiteration of the main goals of this lesson (see lesson summary)

Objectives
  1. Allow students to relate to their natural environment in order to understand the concept of “ecosystems”. - Most science textbooks use the African continent ecosystem (desert, interaction of wild animals in Africa) to introduce the concept. I do not think that is wrong, but I want to enable to students to relate it more to things the readily know and are familiar about. This will also enable them to care about their own natural resources. Since I am teaching in Maryland, I hope that illustrating what ecosystems are using the Chesapeake Bay will hopefully   maybe even encourage students to learn more about science and work scientist around this area.
  2. Let students understand what components make up an ecosystem. – Here I want students to understand that an ecosystem is not animals, not just plants, but also include the inanimate (abiotic) components such as the wind, temperature, salinity, the sand, soil and water that ecosystem. I find in my teaching that when I ask students to make a list of things they will find in an ecosystem, they readily make mention of all the living things and disregard the non-living things. The beauty of the Chesapeake bay ecosystem , is that here the non-living component can be even become a new food web (based on the detritus feeding food chain).
  3. Use the components of the Chesapeake Bay Ecosystem EwE model to illustrate the trophic interactions and the energy balance and energy flow in this ecosystem. – Here students should be able to understand that even in aquatic organisms the producers are still plants, although they may not exactly look like the green plants in the terrestrial environment. Allow them to understand that many producers in the aquatic ecosystem are even microscopic, but they have one thing in common with terrestrial producers – their dependency on the energy of the sun.
Materials

Materials Needed: (6 sets are needed for   regular class size of 25-30)

 

  1. Presentation Board – laminated
  2. The " Chesapeake Bay Ecosystem" (Microsoft Publisher).
  3. Basket – containing pictures of various biotic and abiotic (sources for websites where you can get images are linked) component in the Chesapeake bay ecosystem. (all pictures are laminated individually to avoid damage)
  4. White board markers or water soluble markers to write down the trophic levels and various food chain and food web based on the feeding relationship of the various biotic components in their basket in their presentation board.
  5. Masking Tape – to tape to their board the various materials from their basket. (A light tape will be advisable so that they can easily move or change the positions of their ecosystem model.)
  6. Dictionary (does not need to be a set of six)
Procedure

The lesson is about the special ecosystem that is a very valuable resource of the United States. In this lesson, students will create an ecosystem model containing the following:

 

  1. Students will take out the contents from the harvest of the Chesapeake Basket. They will identify what the pictures are and arrange them in their presentation board in the order of their trophic position. You will not tell them or answer their question, instead they will read the publication (The Chesapeake Bay Ecosystem) to look up  the materials they have. In case they have difficulty understanding the vocabulary, they will be asked to use the dictionary to find the meaning of the word. This is to develop their research skill.
  2. Students will draw lines with the marker provided to show how each part of the ecosystem are related by drawing the lines to show their feeding order (food chain).
  3. They should also realize that in an ecosystem, an organism does not only rely on one kind of food, thus there may be one or more consumer using the same food, resulting to a food web and a trophic position of not 2, 3 or 4 but somewhere in between.
  4. Students will discuss their group’s model within their group.
References
1. The Chesapeake Bay ecosystem publication - produced by me during my six weeks work at NOAA
State Standards
3.1.3- The student will be able to compare the transfer and use of matter and energy in photosynthetic and non-photosynthetic organisms.
3.5.1- The student will analyze the relationships between biotic diversity and abiotic factors in environments and the resulting influence on ecosystems.
3.5.2- The student will analyze the interrelationships and interdependencies among different organisms and explain how these relationships contribute to the stabilty of the ecosystem.
3.5.4- The student will illustrate how all organisms are part of and depend on two major global food webs that are positively or negatively influenced by human activity and technology.
Lesson Resources