Water: Educator Resources
What are Wetlands?
Wetlands are a very important part of the environment. They help slow down and clean up polluted runoff from the land and provide habitat for animals. You will find wetlands in areas where water covers the soil or is present at or near the ground surface for part or all of the year. Sometimes a wetland will actually appear dry at certain times of the year! You can often tell if something is a wetland by the types of plants that are growing in it. Most of these plants, like cattails and swamp roses, are adapted to living in the water and can't live in dry soil for very long.
Why are Wetlands Important for Our Environment?
Wetlands as sponges
Have you ever poured water onto a damp sponge? The sponge will hold a lot of water before it slowly starts to leak. The same happens in a wetland. A wetland will trap runoff water that flows into it during a rainstorm and will slowly release the water later. This helps to prevent flooding.
Wetlands as filters
After being trapped by the wetland sponge, polluted runoff water moves slowly through a wetland, finding its way around plants and through small spaces in the soil. While it moves, the nutrients are absorbed by the plant roots that poke through the soil spaces. Some spaces are very small and pollutants get trapped. Sometimes the pollutants just stick to the soil. By the time the water leaves the wetland it is much cleaner than it was when it entered. This is why many people think of wetlands as nature's filter system.
Wetlands as habitat
Wetlands are home to many types of macroinvertebrates, fish, amphibians, birds, mammals, and reptiles. These animals rely on the plentiful food, water, and shelter that the wetland offers. While some animals spend their whole lives in a wetland, many use it only for a particular time in their lives, such as for hatching eggs and raising young.
Back in the early 1970s the United States was losing over 450,000 acres every year to development. Since then we've tried harder to protect wetland areas. But, today we are still losing over 58,000 acres of wetlands EVERY YEAR. That is an area equal to almost 44,000 football fields! Wetlands are being destroyed to make way for farmland, highways, houses, and development of commercial sites like malls. We need to try harder to control changes in our watersheds so we can stop losing wetlands.