Part
1: Contamination of the Wetlands
Objectives
After participating in the program Materials
and the Environment, Part 1, students will be able to:
| ·
locate various features of California's San Joaquin Valley |
| ·
describe how wetlands can be contaminated by irrigation practices |
| ·
list some trace elements found in sea water and their location
on the periodic table |
| ·
restate that selenium (Se) is a necessary nutrient |
| ·
recognize that too much selenium (Se) is toxic |
| ·
describe how salts, minerals, and trace elements can be flushed
out of the soil by water |
| ·
explain that salts, minerals, and trace elements can be left behind
and concentrated when water is evaporated |
Vocabulary
*trace elements |
any
element present in minute quantities in an organism, food, soil, water,
etc. |
| *sediment
|
matter
that settles to the bottom of a liquid and/or matter that is deposited
by water or wind |
| *irrigation |
the
water supplied to land and/or crops by means of artificial ditches
or channels or sprinklers |
| *wetlands |
swamps
or marshes |
| *selenium |
Se,
a gray, nonmetallic element of the sulfur group |
| *Periodic
Table |
an
arrangement of the chemical elements according to their atomic numbers |
Materials
(For each group)
· scale (for
weighing out 1 g)
· weighing
papers
· salt
· plastic
container
· coffee filter
· rubber band
· set of measuring
cups and spoons
· potting
soil
·water
· vitamin
bottle (with some amount of Se listed)
(For each student)
· worksheet
· Periodic
Table
(For the teacher)
· small bottle
or vial with 1 mg salt
· Pyrex container
· rubber band
· coffee filter
· salt
·potting soil
· water
· Bunsen burner
or hot plate |
 |
Total
Activity Time: 1 Hour 30 Minutes
~~
Disclaimer:
These activities were adapted from the website: http://www.lbl.gov/MicroWorlds/Wetlands.
This
work was supported by the Center on Polymer Interfaces and Macromolecular
Assemblies (CPIMA)
as part of the NSF Materials Science and Engineering Center program under
Grant DMR 9808677
Copyright
1996 - 2003, Leland Stanford Junior University. All rights reserved.
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