The Importance of Wetlands

People used to think that wetlands were wasted land. Developers would drain them with ditches, fill them in with tons of soil, and build houses, schools, and parking areas on them. Then scientists began to realize the important role wetlands played in the environment.


Create a Flood

How do wetlands protect towns from flooding? To test this you will need 2 pie or cake pans, a ¼ cup measuring cup, a damp sponge, and some water.

  • Lay the two pans next to each other. Wring out the sponge so that it has no excess water. Then place it in the center of one of the pans.

  • Pour ¼ cup water into the empty pan. Notice how it covers the bottom of the pan. Now pour a ¼ cup water into the second pan right onto the sponge.

  • What is the difference in the water level of the pans? Imagine that these pans are each small valleys with tiny towns. The pan without the sponge would be underwater. How would the town with the sponge fare? Towns with wetlands are like the pan with the sponge. Wetlands take on and hold excess water in a storm and release it slowly without flooding.

Wetlands act like giant sponges during storms. They soak up extra storm water and afterward release it slowly back into the water cycle. This helps prevent flooding. Towns where people have drained wetlands have found that in a big storm, their streets and homes are often flooded because there are no wetlands to soak up the excess water.

Wetlands also act as giant filters where pollutants are absorbed and dissolved over time. Though wetlands can become polluted from dumping, wastewater, and fertilizer runoff from farm fields, they are able to process some pollutants over time because of all the microorganisms and plants living there.

Wetlands are especially important for providing homes and breeding grounds to millions of birds, fish, and amphibians worldwide. Many wetlands have become national wildlife refuges, where you can go to take pictures and look at birds and animals.

The Everglades

The Everglades are a huge wetland that once covered more than four million acres of southern Florida.

Sometimes called the “river of grass,” the Everglades are a shallow sheet of water that slowly flowed across a grassy plain. In the late 1800s people began draining parts of the Everglades for development. Roads were built and towns sprang up. The Everglades shrank to half its original size. Cities like Miami grew up where once there was a thriving wetland. Sewage and waste from the cities were pumped into the remaining wetlands. Over time scientists began to see the importance of the Everglades. Even with its smaller size, the Everglades filtered the pollutants coming from the cities, absorbing the worst of it like a sewage treatment plant. During storms the Everglades protected the cities from storm surge flooding. They also are just a great place to visit and see wildlife.

Did You Know?

Pollution and Breathing

People in areas of high air pollution can develop breathing problems, especially kids! The World Health Organization has estimated that more than four million people die each year from air pollution.

Much Too Much!

Use the decoder to figure out how one student took recycling a little too far!


Is That Building Melting?

Over decades acid rain can actually corrode buildings and statues. Try this experiment to see how this happens.

  • Fill one glass bowl with water.

  • Fill one glass bowl with vinegar.

  • Add a piece of chalk (the same size) to each bowl and leave them over night. Chalk is made from a similar mineral that some buildings are made of — limestone.

  • In the morning take out both chalk pieces. Are they still the same size?

  • Over a long period of time acid rain corrodes buildings the way the vinegar corroded the chalk.

Now there is a big effort to protect what is left of the Everglades. Thousands of acres of man-made treatment marshes have been planted between the cities and the Everglades. They use native plants to naturally clean harmful nutrients from water flowing into the Everglades. Farmers have had to change their use of pesticides and fertilizers to avoid it reaching the Everglades. Hopefully over time, the Everglades' many endangered animals will begin to thrive again and this unique and beneficial wetland can be preserved for all time.

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