Summary
Wetland functions will be selected for incorporation in the planned wetland design. Goals for the wetland project will be established.

Materials

Making Connections
Not all wetland functions are compatible, nor are all goals financially attainable. As with most decisions in our lives, it comes down to making choices. Students have an opportunity to promote their personal interests in the planned wetland as group goals are set for the wetland design.

Background
A wetland function is a task performed by a wetland regardless of how human society values that task. The structure of a wetland determines which functions it can perform. If the wetland is to function as fish habitat, then it must be deep enough for the survival of the desired fish species. If the wetland is to function as frog habitat, it needs gently sloping sides so young frogs can climb out.

A wetland's value is subjective; it is defined as the worth society places the wetland's attributes, and this value may change over time. For instance, one wetland function is to provide a nursery for many creatures. Society sees this as valuable if the creatures are fish, frogs, and birds, and considers it not valuable if biting insects such as mosquitoes breed there.

One choice you have to make is whether you will create the planned wetland from a non-wetland area, enhance an existing wetland, or restore an area that was previously a wetland.

Created wetlands result from modification of a site where wetlands do not currently exist and where wetlands did not previously exist. Beavers create wetlands by flooding areas that were previously dry. At schoolyard sites, you can create conditions for a wetland to exist. This generally means providing water to a planned wetland site and ensuring that sufficient water will remain at the site to sustain it, as well as any other conditions needed to support the wetland community. This can be accomplished through several means, but generally includes excavation to lower the ground elevation and construction of an earthen dike or berm to impound water. Sometimes a liner of plastic or clay is needed. It is important to understand that just digging a hole does not create a wetland.

Wetland restoration means returning an altered wetland (e.g., one that was filled in) back to a functioning wetland. Restoration projects can be classified as hydrologic or biological. Hydrologic restoration usually involves removing barriers that block water flow to a site (as in some tidal wetland areas), or plugging tile drains or drainage ditches to restore preexisting water sources (as in the Prairie Pothole Region of the Midwest and the swamp areas of the Eastern Coastal Plain). Although biological restoration generally means reestablishing wetland plant species along with hydrologic restoration, in some cases restoring the biological portion of a system may be all that is needed. In the southern United States, some marginal agricultural lands, which were at one time wetlands, have been successfully replanted with wetland tree saplings in an effort to increase the acreage of bottomland hardwood forests.

Wetland enhancement generally is the process by which some wetland functions are improved as part of an overall management plan. As a result, other wetland functions may be minimized. This may take the form of creating habitat for rare or endangered species through construction, placement, and maintenance of nesting structures. This may, however, cause a decline in other wetland species through predation or competition. A site dominated by invasive or alien plant species, such as purple loosetrife, might be replanted with a variety of more desirable native species that support native wildlife. Often, wetland managers vary water levels (some seasons high, some seasons low) to support a variety of waterfowl in wildlife management areas.

After choosing the type of planned wetland and identifying a potential wetland site, it's time to set specific, appropriate goals for the project. For example, if your chosen site is low in the topography with predominantly silt/clay soil and water present only during the spring, then a goal of providing habitat for frogs, turtles, butterflies, and birds would be appropriate, but fish habitat is not possible.

Procedure
Warm Up - A function is a job that is performed or a role that is filled. A value is the degree of importance (either positive or negative) that is associated with a function. Discuss the difference between a function and a value. Provide an example (such as the function and value of butterflies or cows), then have students suggest some wetland functions. As students offer suggestions, list them on the board.

Activity
Grades K-4
Using an overhead projector, complete the Grades 5-12 activity as a class. As an alternative, have students in higher grades interview younger students about what they want the wetland to accomplish.

Grades 5-12
1. Each student should consider the list provided on the "Choices" Student Page, placing a check under "My Choice" for eight wetland functions that they would like the planned wetland to perform. Add any that do not appear on the list. Do not limit possibilities even if some seem contradictory; you can sort this out later.

2. Consult other teachers and other students, the administration, those in charge of maintenance, the parent-teacher organization, local garden clubs — anyone who has a stake in the project. Listen to concerns as well as desires. If the school administration says “no open water,” make sure that appears on the list even if it is a negative characteristic.

3. Within small groups, discuss the appropriateness of each function, its importance, and its compatibility with other functions. Within each group, select up to eight functions desired for the planned wetland. Mark these choices on the "Choices" Student Page under "Group Choice."

4. Each group reports its goals to the class. Compare lists by writing them on the board, on an overhead transparency of "Group Choices," or on large (poster-size) sheets of paper that you can post temporarily along a wall. Which goals are on most lists? Which are on only one? Why? Which items are too expensive? (Consider postponing expensive ones until more funds are available.) Which items are inconsistent with the amount of water and and timing of water availability within the planned wetland? These must be eliminated unless an additional supply of water is available.

5. As a class, select a final list of wetland functions that are consistent with the water supply, administrative parameters, and available funds. Mark these in the column "Class Choice" on the "Choices" Student Page.

Wrap Up and Action

Assessment
Did each student participate in the decision-making process? Are the wetland goals compatible? Is the wetland project reasonable in view of the muscle power and financial resources available?

Extensions
Visit a nearby planned wetland, such as a stormwater runoff pond, and identify the functions of that wetland. This can also be accomplished with pictures or videos of wetlands.

Resources
Mitsch, W.J. and J.G. Gosselink. 1986. Wetlands. Van Nostrand Reinhold Co., New York, NY.

Salvesen, David. 1990. Wetlands; Mitigating and Regulating Development Impacts. ULI–the Urban Land Institute, Washington, DC.

Sather, J.H. and R.D. Smith. 1984. An Overview of Major Wetland Functions and Values. U.S. Fish and Wildlife Service, Washington, DC.

Smith, R.D., A. Ammann, C. Bartoldus, and M.M. Brinson. 1995. An Approach for Assessing Wetland Functions Using Hydrogeomorphic Classification, Reference Wetlands, and Functional Indices. Technical Report WRP-DE-9. U.S. Army Corps of Engineers, Vicksburg, MS.

Tiner, R.W., Jr. 1984. Wetlands of the United States: Current Status and Recent Trends. U.S. Fish and Wildlife Service, National Wetlands Inventory, Springfield, VA (#PB90-198201).