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Introduction
Without water our blue planet would shrivel up and die. Water
makes us unique among the nine planets circling the sun. Wars are
fought over water, its use and misuse, and foreign policies center
around the availability of water. To get students to understand
the importance of water and how easy it is to take it for granted is a
goal all teachers should have when teaching about water's quality.
Water makes up our
watersheds.
Generally, watersheds
are described as the land that water flows across or under on its way to
the lowest point - a stream, river, or lake. Watersheds can be large or
small, draining a single valley or the entire basin. On its way, water
travels over the surface and across farm fields, forest land, suburban
lawns and city streets, or it seeps into the soil and travels as ground
water. Everyone lives in a watershed and we all influence what happens
there by how we treat the natural resources - the soil, water, air,
plants, and animals. A healthy watershed not only stores but also filters
water for a river or stream.
Both pollutants and
nutrients found within a watershed will eventually make their way into the
streams and rivers of that watershed, and also become part of the water
cycle. The growth of human populations can result in the diversion
of the water as the need for water and hydroelectric power rises.
Fertilizers and pesticides are major sources of contamination of
watersheds. Most often it is the wildlife within a watershed that
suffers the most from water contamination, as slight changes in pH can
upset the natural balance of the water. Food chains can be altered
for many years to come and water supplies can be contaminated also. When water hits the earth and percolates
through the soil into the water table, soil, rocks, and sand filter out
many of the impurities carried by the water.
It is important when
teaching about watersheds to have students realize they live within
a watershed, and the way they live can affect the water they drink.
But they can do something about keeping it healthy!
The activities listed at
the left offer a variety of ways to teach students from elementary through
high school various aspects of water.
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