In a recent column, we talked about the importance of drainage maintenance. This week we are going in the opposite direction to discuss the importance of wetlands.
I know it looks like I am crazy (my brother would certainly attest to that) but, in reality, all of the Earth’s water is interconnected. The water cycle includes condensation, precipitation, surface runoff, evaporation, transpiration, groundwater recharge and wetlands. Believe it or not, we have the same amount of water on Earth today as when the dinosaurs roamed.
Why are wetlands important? Wetlands are among the most productive ecosystems in the world, comparable to rain forests and coral reefs. There are many different kinds of wetlands but all are chock full of microbes, plants, insects, amphibians, reptiles, birds, fish and mammals.
To better illustrate this, I want you to imagine a mystery box with the following items inside: a small pillow, a sponge, a small doll crib, a bottle of antacid tablets, a box of cereal and a paper coffee filter. We are going to mentally remove one item at a time from the box and use it to explain why wetlands are so critical.
In your mind, pull the small pillow from the box. This signifies that a wetland is a resting place. Migratory birds depend on wetlands to survive their flights between their breeding grounds and their winter habitats. It is estimated that some 75 percent of all waterfowl breed exclusively in wetlands.
Next is the sponge. A wetland is a sponge, absorbing excess water caused by runoff. Some wetlands, particularly those on floodplains and in coastal areas, function as flood control by storing excess water during storm events. The loss of important wetlands along the Gulf coast contributed to the horrific devastation wrought by Hurricane Katrina in 2005.
The small doll crib explains that a wetland functions as a nursery, providing shelter, protection and food for young wildlife. Many species of fish that are important for commercial and personal use spend part, or all, of their life cycles in fertile wetlands adjacent to larger, more open bodies of water. This includes bass, salmon, walleye, perch and pickerel. Coastal wetlands are essential habitats for fish, shellfish, blue crabs and shrimp – some of my favorite foods! Frogs, toads, turtles, salamanders, snakes, dragonflies, water striders, clams and crayfish flourish in wetland habitats. Many mammals, such as deer, beaver, otter, black bear and others, depend on wetlands too.
The bottle of antacid tablets demonstrates that wetlands eliminate toxic substances by trapping and neutralizing pollutants. An example of this can be found in Ohio. A “treatment train” was constructed in 2013 to improve water quality in Grand Lake St. Marys. This process combines wetlands and water dosing to filter runoff from the watershed before it enters the lake. In this process, water is lifted from Prairie Creek, treated with alum, then released into former farmlands that have been repurposed as wetlands. The water settles in the wetland and is naturally filtered prior to entering the lake.
Next, please pull out the box of cereal from the mystery box. Wetlands provide food for wildlife and humans. We already mentioned fish but wetlands grow rice and cranberries. The list grows when we consider recreational hunting for ducks, deer and other wildlife that are harvested for the dinner table.
The last item is the coffee filter. Wetlands improve water quality by acting as sediment basins. Wetland vegetation is often dense, above and below ground. These plants slow down surface runoff and encourage sediment deposition so that clean water then flows into our rivers, streams, lakes and oceans.
These are just a few excellent examples of the importance of wetlands to water quality, locally and around the world. I could have filled up the mystery box with all kinds of props but my colleagues already accuse me of being too wordy!
Unfortunately, a huge percentage of our nation’s wetlands have been lost or degraded due to human impacts, such as drainage, dredging, deposition of fill material, diking, damming and mining. Wetlands are unique, diverse, productive and important to our quality of life and quality of water.
The curriculum guide Project Aquatic WILD provided much of the information for this article. The Delaware Soil and Water Conservation District hosts educator workshops throughout the year, including Project WILD. Please visit us at www.delawareswcd.org or www.facebook.com/DelawareSWCD to learn more.