BACKGROUND:

An environment refers to the surroundings of an area.  Environments are different from place to place, and change with time.  Within environments you have different parameters that allow ecosystems to maintain themselves.  In order to restore or to make an environment friendly again to native species, environmentalists need to understand the entire ecosystem. 

Although the media talks about chemicals being harmful to our environment they fail to point out that chemicals make-up everything.  There are  good and bad chemicals depending on how specific organisms react to them.  What is good for one species, might be harmful to other species.  Chemicals can "control" an environment, and can also influence organisms that live in that specific environment.

Major land and aquatic ecosystems require the following components in order to be maintained.

1. Sunlight - the ultimate source of energy for primary producers, controls a photochemical process
2. Inorganic substances - carbon, nitrogen, oxygen, minerals, and water
3. Organic compounds - fats, proteins, carbohydrates
4. Climate or weather - wind, water currents, temperature, rain, snow, and humidity
5. Producers - autotrophic organisms for most part green plants, that capture sunlight, convert energy into organic nutrients, and release oxygen
6. Macroconsumers - heterotrophic organisms, animals for the most part that eat other organisms or organic matter
7. Microconsumers - decomposer organisms, largely bacteria and fungi that break down the  organic components of dead organisms

Notice that all the components are ultimately composed of chemicals.  However, there are inorganic components that are "given" or specific to an area.  The ecosystem has to build itself on soil (organic matter + rock).   Organic matter is carbon based, but rocks can be made of a variety of chemical compounds which add character to a particular soil. Remember, minerals make-up rocks, and minerals can be composed of elements or compounds. 

PROCEDURE:

1. Read Wetland in the City.  You may want to discuss some of the terms used in the story. Include:
       a.  Sag ponds are associated with faults and where water can flow upwards.
       b.  Tule Ponds at Tyson Lagoon is an urban flood control system.  More information on the components of its ecosystem can be found: http://msnucleus.org/watersheds/tule/tule.html
       c.  The characters represent real people involved with development of Tule Ponds at Tyson Lagoon.  Richard Wetzig, a retired ecological engineer designed Tule Ponds.  Donald La Belle is the director of Alameda County Public Works in California.
       d.  Tule Ponds may be older than 4000 years.  It has seen many changes from large extinct mammals, Ohlone Native Americans, Spaniards, and now the City of Fremont. 
       e.  Engineer Richard learns about the complexities of the interaction of biology with the physical state of the ponds.  He realizes that restoration takes a long time. 
     
2. Discuss all the information that Engineer Richard needs to find out to really understand how to restore an impacted area.  If you have a local area that is being restored or needs to be restored you might want to make a list of what needs to be considered for restoration.  It could be a local lake, stream, or wetland area.
     
3. The worksheet is designed for students to look at minerals.  The students should use a periodic table if they are not sure what the symbols stand for. ANSWERS: 
   1. Mg,Si,O,H; Cu; Ca,C,O;  
   2. Si,O; Pb, S; Ca, F; Al; Ca, K, Si, O;  
   3. Ba, S, O; Si, O; Ca, C, O; Hg, S.   
   4. The soil in #3 because mercury is toxic to many organisms, especially humans.