The transitional zone between land and water is referred to as a wetland, and marshes make up one third of Florida’s wetlands. "Marshes are wetlands dominated by herbaceous plants rooted in and generally emergent from shallow water that stands at or above the ground surface for much of the year" (Myers & Ewel, 1990). There are nine types of Florida marshes, and the wet prairie is the most common type of marsh found on Florida Gulf Coast University’s campus.
A wet prairie ecosystem can be identified by its lack of trees, sparse to dense ground cover of grasses and herbs, and flat terrain. The timing and length of the dry season, relative to the seed types available in the substrate, determine which flora germinate and flourish. Some examples of plant species found in marshes are maidencane (Panicum hemitomon), cordgrass (Spartina bakeri), beakrush (Rhynchospora spp.), and muhly (Muhlenbergia fillipes). Subtropical locations, fluctuating water levels, recurring fires, and hard water also shape marshes.
Wet prairies are shallow basins that have good tolerance to both flooding and drying out. Wet prairies have short hydroperiods, having less than six months of inundation (standing water) resulting in the most species-rich of all Florida marshes. The soil is sandy with some organic content. Organic matter accumulation is low, only a few centimeters at most, as opposed to cypress swamps that accumulate ten times that amount, and more. Wet prairies also have high fire frequency, ranging from once every two to four years to once per decade. This limits woody vegetation invasion, which retards or sometimes reverses peat accumulation. Compared to other types of Florida marsh ecosystems, wet prairies have a shorter hydroperiod (amount of time when the land is inundated), more frequent fires, and lower accumulation of organic matter.
Although wet prairies support a greater number of amphibian and reptile species, like the green tree frog (Hyla cinerea), mud turtle (Kinosternon bauri), pygmy rattlesnake (Sistrurus miliarius), and american alligator (Alligator mississippiensis), marshes in general have a wide species variety. Dragonflies, mayflies, mosquitoes, and horseflies are all found in marshes, in addition to some large mammals like the white-tailed deer (Odocoileus virginianus) and Florida panther (Felis concolor coryi). Birds such as the green-backed heron and white ibis frequent marsh habitats. Threatened and endangered species such as snail kites (Rostrahamus sociabilis) and wood storks (Mycteria Americana) forage in marshes and nest in swamp forest vegetation. The wood storks rely on this system for their food supply, and their numbers are still decreasing partly because of wetland drainage that reduces food availability for growth and reproduction.
Wet prairie systems are often associated with hydric (wet) or mesic (wet part of the year, dry part of the year) flatwoods, dry prairie, and hammocks. Animal species from these neighboring ecosystems often make use of the wet prairies as well. When fire occurs less frequently, wax myrtle may begin to dominate the system. Wet prairies in South Florida are also prone to invasion by melaleuca. Recovery from disturbances to the system is often slow, and introduction of other species may result in permanent changes to the ecosystem.
Marshes provide numerous environmental services such as recreation, flood control, fish and wildlife production, and water storage and supply. Although valuing wetlands in general is difficult, marsh services can and have been valued. The fisheries value is $1,333 per acre per year, and the water-treatment value is $1,112 per acre per year (University of South Florida). These figures alone provide reason enough to preserve marshes, but marshes play an even greater integrated role. Not only do they filter excess pollutants from residential and agricultural runoff, but they also foster evapotranspiration. This release of water vapor that condenses into rainfall is comparable to the amount that condenses from open bodies of water. Active management needs to occur to stop the lowering of groundwater levels: 46% of Florida’s 20 million wetland acres have been destroyed, and an additional 26,000 acres per year are still being destroyed (University of South Florida).