Weber State University
Department of Botany
Antelope Island Field Trip
Wetlands, as the term might suggest, are areas where water covers the soil, or is present either at or near the surface all year or at least for substantial parts of the year, especially during the growing season. Some of our most valuable and productive wetlands are only seasonally wet. Wetlands are an important link between the land and water and are as productive as are rain forests and coral reef ecosystems. Water saturation (hydrology) largely determines how the soil develops and the types of plant and animal communities living in and on the soil. Wetlands may support both aquatic and terrestrial species. Generally, the prolonged presence of water creates conditions favoring specially adapted plants (hydrophytes). Wetlands vary widely because of regional and local difference in soils, topography, climate, hydrology, water chemistry, existing vegetation, and other factors, especially human disturbance.
In general we talk of two broad categories of wetlands: (a) Coastal Wetlands and (b) Inland Wetlands.
Coastal Wetlands are found along the oceans and closely linked to estuaries where seawater and freshwater mix. Grasses, sedges, and rushes that are salt tolerant take advantage of nutrients flowing into their environment once or twice daily (tides) resulting in tidal salt marshes that are exceptionally high in total production of organic matter.
Inland Wetlands are found on floodplains along rivers & streams (riparian wetlands), in depressions surrounded by dry land, for example potholes, basins, and playas, along margins of lakes and ponds, and any other low-lying area where groundwater intercepts the soil surface. Inland wetlands include marshes and wet meadows dominated by herbaceous plants and swamps dominated by shrubs and trees. Near the Great Salt Lake we find inland saline and alkaline marshes.
It is estimated that Utah has lost approximately 30% of its original wetlands. Less than 1% of Utah’s total land area meets the criteria set for wetlands. Of all of Utah’s wetlands, seventy-five percent (about 400,000 acres) are part of the "Greater Salt Lake Ecosystem". This ecosystem includes the Great Salt Lake itself, the wetlands that lie adjacent to the lake, and the three rivers that drain into the lake....the Bear, Weber, and Jordan Rivers, their associated tributaries and the wetlands contained in their floodplains.
Immediately adjacent to and/or part of the eastern edge of the Great Salt Lake lies a saline marsh community. Elevations range from 4200 to 4300 feet. The ground is essentially flat and covered throughout much of the year with shallow, brackish water.
Cattails and tules are the dominant emergent vegetation, while pond weeds and smart weeds are to be found floating in most areas of standing, open water. Open flat lands are often covered with goosefoot.
Important plants are: Scirpus acutus, Scirpus maritimus, Typha domingensis, Typha latifolia, Salicornia rubra, Eleocharis palustris, Carex nebraskensis, Carex aquatilis, Polygonum amphibium, Polygonum convolvulus, Polygonum persicaria, Polygonum punctatum, Potamogeton pectinatus, Conium maculatum, Distichlis spicata, Solanum dulcamara, Polypogon monspielensis.
For more details on GSL vegetation, including the Riparian communities near the GSL, consult the Vegetation portion of Dr. Clark’s topics on this web site.
Value of Wetlands:
Considerable attention has recently been paid to wetlands values both in this country and elsewhere. Once regarded as useless, disease-ridden environments, wetlands in fact provide values that no other ecosystem can provide, including: natural and waste-water quality improvement, flood protection, shoreline erosion control, opportunities for recreation and aesthetic appreciation, and natural products for our use at little or no cost. Wetlands provide one or more of these values and are worth protecting, even at considerable economic cost.
Water Quality, Hydrology, and Flood Control:
As surface runoff water passes through a healthy natural wetland, the wetland plants and animals act as a filter retaining excess nutrients and breaking down some pollutants before this surface flow reaches open water, thereby maintaining high surface water quality. Sediments are also trapped which protects fish and amphibian egg development in lakes and streams. In performing this natural filtration function, wetlands save us a great deal of money.
Artificially constructed wetlands are also currently being employed to treat waste-water so that high open water quality is maintained. Constructed wetlands have become routine in waste-water engineering schemes bringing the disciplines of engineering and biology closer together.
In addition to improving water quality through filtration, most wetlands act as a sponge and absorb water when it is available in excess and release it into the groundwater supply slowly. This positive impact on the hydrology ensures that we have adequate stream-flow throughout the year. Permanent streams become temporary or seasonal if wetland integrity is not maintained. In riparian systems, this sponge action of wetland plants prevents floods. Preserving and restoring damaged wetlands can lead to flood control which otherwise would require very expensive dredging operations and levee construction.
Wetlands at the margins of lakes, rivers, bays and the ocean protect shorelines and stream banks against erosion. Erosion control is so important today that many states spend considerable resources to protect sensitive areas along rivers and coasts.
Coastal areas are subjected to tremendous erosion when exposed to storm surges. The greater the wetlands are negatively impacted by "development" the greater is the erosion. Wetlands hold soil in place with their roots, absorb the energy of waves, and break up the flow of stream or river currents.
Fish and Wildlife Habitat:
More than one-third of the United States’ threatened and endangered species live ONLY in wetlands and nearly half use wetlands at some point in their lives. Estuarine and marine fish and shellfish, various coastal birds, and certain mammals must have coastal wetlands to survive. Most commercial and game fish use coastal wetlands as nurseries for food, shelter, and protection of their young.
Our wetlands are vital to breeding and migratory bird populations as has been discussed in the previous section on "Life in the Great Salt Lake". International agreements to protect wetlands of international importance have been entered into because some species of migratory birds are completely dependent on certain wetlands and would become extinct if those wetlands were destroyed.
Recreation and Aesthetics:
Wetlands have recreational, historical, scientific, and cultural values. More than half of the U.S. Adult population (99 million) hunt, fish, birdwatch, or photograph wildlife in wetlands. School field trips often involve the study of wetlands. Painters and writers often find inspiration to create their art in wetlands. A total of nearly $60 billion is spent annually on the above activities.
Natural Products for Our Economy:
Many of our nation’s fishing and shellfishing industries harvest wetland-dependent species; the catch is valued at $15 billion a year. In the Southeast, for example, nearly all the commercial harvest are fish and shellfish that depend on the estuary-coastal wetland system.
Several plants are very valuable from our wetlands. Think of the value of blueberries, cranberries, timber and wild rice to our economy. Many wetland plants and soils provide medicines today and promise to do so in the future.
Despite all the above benefits provided by wetlands, the U.S. loses about 60,000 acres of wetlands per year. Additionally, non-native (alien) species of plants and animals as well as global warming & climate change contribute to wetlands loss and degradation. What is being done to protect these valuable ecosystems? Several federal and state agencies devote considerable resources to wetlands protection. The EPA has principal responsibility here. They have a number of programs for wetland conservation, restoration, and monitoring. EPA, along with the U.S. Army Corps of Engineers (Corps) establishes environmental standards for reviewing permits for discharges that affect wetlands, such as residential development, roads (e.g. Legacy Highway), and levees. Under Section 404 of the Clean Water Act, the Corps issues permits that meet environmental standards, after allowing the public to comment. The federal government as well as the states, tribes, local governments, and private organizations work together to solve complex environmental problems involving wetlands protection. What are you prepared to do? There are a number of things you can do to help. Consult the internet and your instructor for help.
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