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Why Are Wetlands Important?. By: Erin Janes & Danna Svejkosky MARS 689: Wetland Ecology Dr. Tom Linton Fall 2003. The Value of Wetlands. Functions and Values. Air Quality. Stability of global levels of: 1 Available nitrogen Atmospheric sulfur Carbon dioxide Methane.
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Why Are Wetlands Important? By: Erin Janes & Danna Svejkosky MARS 689: Wetland Ecology Dr. Tom Linton Fall 2003
The Value of Wetlands Functions and Values
Air Quality Stability of global levels of:1 • Available nitrogen • Atmospheric sulfur • Carbon dioxide • Methane Photo by: Mike P. Murphree
Water QualityChemical and Physical Properties Hydrologic conditions can be modified by: • Nutrient availability • Degree of substrate anoxia • Soil salinity • Sediment properties • pH
Water QualityBiotic Properties Vegetation can control water conditions through: • Peat building • Sediment trapping • Nutrient retention • Water shading • Transpiration
Storm Abatement • Wetlands act as buffer of storm surge and wave energy • Sustain minimal damage • Shelter inland property “Regional wetlands are integral parts of larger landscapes—drainage basins, estuaries.”1
Erosion Control Shoreline stabilization • Aerial parts of marsh plants dissipate wave energy • Both offshore and longshore transport of sediment are reduced • Dense stands can create a depositional environment • Plants form dense root-rhizome mats, adding stability to the shore sediment • Particularly important during winter storms when aerial stems provide only limited resistance to the impact of waves
Erosion Control Planting marsh grass is a better alternative than: • Bulkheads • Seawalls • Rip rap Gulf Intercoastal Waterway Photo Courtesy of USACE, Galveston District
Shoreline Erosion Problems?Think Green… From the Virginia Institute of Marine Science (VIMS)
Flood Protection • Intercept storm runoff and store storm waters1 • Reduces flood damage caused by peak flows • Seasonal variations Case Study USACE study led to Corp’s decision to purchase 3,400 hectares of wetlands in the Charles River Basin (Massachusetts) to effectively prevent flood damage, rather than build expensive flood-control structures to protect the city of Boston at the savings of $17 million per year.1
Fish Habitat • Ecosystem Diversity and Stability • Spawning Habitat • Nursery Habitat • Food Production
Fish Habitat- Ecosystem Diversity and Stability Wetlands play a significant role in maintaining a high level of biological diversity. Wetlands provide a variety of habitats which increases: • species diversity • species richness • species numbers
Fish Habitat- Spawning and Nursery Habitat Fish need specific environmental conditions for adequate spawning areas and juvenile habitat. Spawning fish need: • Good water quality • Protection from predators • An adequate place to deposit eggs Juvenile fish need: • Food • Good water quality • Protection from predators
Fish Habitat- Food Production Nutrients, shallow water, and plants provide the necessary elements for the production of algae, zooplankton, and invertebrates, which are utilized by other fish.
For the Birds Birds use wetlands for: • Breeding • Nesting • Rearing young • A source of drinking water • Feeding • Resting • Shelter • Social interactions
Fish and Wildlife Habitat The U.S. Fish and Wildlife Service estimate that 43% of all threatened and endangered species rely directly or indirectly on wetlands for their survival.
Recreation and Economy Hunting, fishing, hiking, boating, photography, and bird watching opportunities are abundant in our wetlands. ~98 million U.S. adults spend a total of $59.5 billion annually on recreational activities within wetlands.
Commercial Fisheries and Economy Coastal wetlands support 60% - 90% of the commercial fisheries in the United States. • Big Business In Texas:2 • Provides jobs for 30,000 residents • $400 million annually • Shrimp • Oysters • Blue Crab • Black Drum • Southern Flounder
Other Values • Historical • Archeological finds suggesting the use of wetlands for a variety of subsistence and commercial uses • Scientific/Educational • Scientific research to further our understanding of the ecology, geology, chemistry, etc. of the Earth • Source of community education • Cultural • Representation of a community heritage
Other Values, cont. • Aesthetics • High quality of life enjoyed by the general public and property owners