Marsh

A marsh is "a type of wetland, an area of land where water covers ground for long periods of time." Differing from swamps, marshes are mainly dominated by grass and herbaceous plants. Herbaceous plants "have no woody stem above ground, and they grow and die back on a regular cycle." The soil in and around marshes are deposited by the river and are very rich, and this great soil allows for the grass and other plants to continue to spread and sustain [1].

Marshes are divided into three categories, two of which are tidal saltwater marshes and tidal freshwater marshes. Tidal marshes "serve many important functions: they buffer stormy seas, slow shoreline erosion, offer shelter and nesting sites for migratory water birds, and absorb excess nutrients that would lower oxygen levels in the sea and harm wildlife" [1]. Tidal saltwater marshes "occur throughout the Southeast Region’s shorelines at the mouths of rivers [and] support species adapted for life in salty conditions and are always affected by tidal fluctuations" [2]. Ocean tides fill these marshes with saltwater, causing the marsh to become deeper and shallower twice a day, following the oceans high tides and low tides. These marshes support a wide variety of birds, fish, and crustaceans. These different species are able to find shelter and food sources around fjords, allowing for a healthy ecosystem.

Tidal freshwater marshes "are also affected by tidal fluctuations, but are located farther inland, are more influenced by freshwater than saltwater, and are the most prevalent marshes in North America" [2]. Since these marshes are more inland than salt marshes, they are rather indirectly influenced by ocean tides. Instead of the ocean immediately depositing saltwater into these marshes, freshwater marshes "are fed by freshwater streams and do not have a large salt content. They are common boundaries between forests and rivers" [1]. These freshwater marshes support many different species of birds such as ducks, herons, wrens, and blackbirds, that thrive in this environment because of the vast insect population that are vastly common around freshwater marshes.

Inland marshes differ from both of its counterparts, and these "are not tidally influenced and are primarily freshwater," but similar to "to both tidal marshes, grasses typically dominate the understory vegetation with water-loving tree-species (such as cypress, tupelo, maple, and ash) dominating canopies" [2]. Inland marshes can either be aquatic dominated or have much more shallow levels of water. This type of marsh supports a variety of "frogs, snakes, and even apex predators such as bears" [1]. The largest inland freshwater marsh in the United States is the Everglades located in Florida. The everglades are constantly covered by a shallow level of water year-round and are a "home to animals such as ducks, geese, raccoons, turtles, and frogs. Predators such as alligators and panther" [1].

References

[1] National Geographic Society. (2012, October 9). Marsh. Retrieved (2021, July 20), from https://www.nationalgeographic.org/encyclopedia/marsh/

[2] NOAA Fisheries. (2018, June 21). Habitat Matters: Marshes. Retrieved (2021, July 20), from www.fisheries.noaa.gov/feature-story/habitat-matters-marshes