Last updated almost 5 years ago
By definition, wetlands are land that is covered by water or is muddy at least seven to 30 consecutive days and their soils saturated within six to eighteen inches of the surface during the growing season. Wetlands may be wet throughout the year or dry until flooded. Flooding, though, may be seasonal, frequent, or rare. The best wetland identification tool is the presence of water. Marshes and swamps bordering ponds, lakes, bays, and waterways are easy to identify. In some locations, however, the water source may be seasonal rain or runoff and may not be immediately evident. Fortunately, floods leave clues. When the wetland appears dry, look for water-stained leaves, shrubs, and tree trunks; spongy, muddy, or mushy soil; and dry, crack-riddled mud. Wetlands occur in every climate and on every continent except Antarctica, in a surprising variety of locations. Wetlands may occur on coastlines, at inland locations, as low spots in fields, in drainage ditches, or adjacent to bodies of water and waterways. Wetlands range in size from the low spot in the middle of the school yard to swamps and marshes covering hundreds of square miles. Their water may be fresh, salt, or a brackish mix as in estuaries. Sources of water vary from ground water and surface water to tidal inflow or a combination of sources. Wetlands provide invaluable physical, biological, and chemical functions for related ecosystems and their residents. For example, wetland plants improve water quality by trapping toxins and sediments, as well as processing excess nutrients. In some areas, wetlands alter the water supply by discharging or storing, absorbing, and recharging ground water. Wetland plants provide erosion control by stabilizing sediments and creating a buffer against storm-produced waves, tides, and floods. Sadly, more than 50 percent of United States wetlands have been lost since the seventeenth century. Before humans interfered, wetlands were controlled by sea level rise, weather events, erosion, and biological processes. Unfortunately, wetlands have been drained, filled, and dredged for farms, development, and waterways. “Drylands” result when wetlands are filled or their water sources are dammed or diverted. Less than eight million acres of Texas wetlands remain today and coastal wetlands have decreased 35 percent in the last 40 years! We depend on wetlands for fishing and hunting. More than 95 percent of recreational and commercial fishes and shellfish found in the Gulf of Mexico utilize coastal wetlands as nursery grounds. They also provide habitat for 75 percent of North America’s bird species. Wetlands serve as breeding, nesting, and feeding grounds for at least a third of all endangered animal species and many endangered plants. Rice and cranberries are two examples of wetland crops, and wetlands are also utilized by forestry, energy, recreation, and tourism industries. Through education, wetlands will remain healthy and functional.