From the beginning of time, the same amount of water has been splashing around our planet in an everlasting merry-go-round we call the hydrologic cycle. It works like this: when water becomes warm, it changes to vapour-like steam from a bath. This is known as evaporation. Plants and trees that drink moisture from the soil also give it off as vapour through their leaves. This is called transpiration. When vapour cools down, it sticks to tiny dust particles as condensation, then falls to earth as rain, snow, or sleet.
So, through the hydrologic cycle, our water is always moving, except when it is very cold and turns to ice.
There are three different forms of water on our planet. The one we know best is the liquid pouring out of taps or sparkling in lakes, oceans, and puddles. Then, in wintertime (or all year round in some parts of Canada) we can have fun on solid water—ice and snow. Water's third form is as a gas, in steam, clouds, air, fog, and mist.
Water... Or Liquid Gold?
Think of rivers and lakes as the blood-vessels of body earth. They carry nutrients from one part of the planet to another, washing out poisons and recycling and returning life-giving oxygen to the system. But just as your bloodstream can be poisoned, so can water.
Now we realize that our waters are in trouble. For years we have spoiled our rivers and streams with chemicals, covered over marshes and swamps with subdivisions, and wasted water as though there were an endless, free supply.
There are about 100,000 chemicals being used around the world today. About 1,000 new chemicals come on to the market each year. Many of those chemicals, one way or another, find their way into the earth's water supply.
Sewage you flush down the toilet is dumped into rivers; barnyard manure and lawn fertilizers trickle into streams; and tonnes of chemicals from industries gush into lakes. Dishwasher and laundry detergents cause algae blooms that deplete oxygen in our waters. Acid rain, oil spills, salt on our icy roads—all these substances and many more end up in our unsuspecting water systems.
What we do to our water affects us as well as wildlife. Mercury is dumped in a lake, where it is absorbed by tiny organisms and insects. A small fish eats several thousand of the contaminated organisms and, in turn, is eaten by a larger fish. Humans eat the fish and may become seriously ill with mercury poisoning.
It's time we stopped taking water for granted and treated it instead like liquid gold. We simply can't afford to waste, lose, or pollute our wonderful water any longer.
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