These equatorial swamps usually experience year-round heat and humidity. Tall evergreen trees dominate the swamp forests. Many species of these trees, such as bubinga and ovangkol, are harvested for timber. Bubinga and ovangkol are expensive, luxury woods used to make musical instruments such as violins, as well as furniture.
The thick canopy of trees means Congolian swamp forests are more shaded and humid than other wetlands. The muddy floor of these swamps is home to hundreds of insects, reptiles, and amphibians, including dozens of species of frogs. Congolian swamp forests are also home to a wide variety of large mammals.
Most of these mammals are herbivore s. Colobus and mangabey monkeys eat mostly tropical fruit. Other mammals, such as forest buffalo, forest elephants, and lowland gorillas, feed on the abundant vegetation of the wetland.
In fact, an adult male gorilla can eat up to 32 kilograms 45 pounds of leaves, fruit, and bark every day. In more temperate climates, cypress trees often grow out of the still waters of freshwater swamps. Spanish moss may hang from tree branches.
Willows and other shrubs may grow beneath the trees. Angular knobs called cypress knee s sometimes poke as much as 4 meters 13 feet above the water. Scientists are not sure what purpose knees serve. They may simply provide support, or they may transport oxygen to the roots. Tiny water plants called duckweed often form a green cover on the surface of the water. Alligators, frogs, and snakes called water moccasins may swim among the plants. Reptiles and amphibians thrive in freshwater swamps because they are adapted to the fluctuating water levels.
Cypress swamps are common throughout the U. The bayou s of the state of Louisiana, near slow-moving parts of the Mississippi River, are probably the most famous American swamplands. Shrimp, crawfish, wading birds, and fish such as catfish are native to bayous. Distinct cultures have also developed near bayous and other freshwater swamps. In Louisiana, the food and music of Cajun culture is closely associated with bayou wildlife and imagery. Saltwater Swamps Saltwater swamps are usually found along tropical coastlines.
Formation of these swamps begins with bare flats of mud or sand that are thinly covered by seawater during high tides. The brackish water of saltwater swamps is not entirely seawater, but not entirely freshwater, either. Some hydrophytes, such as mangrove trees, can tolerate brackish water. Mangroves are easy to recognize because of their tall, stilt-like roots, which hold the small trunks and branches of the trees above water.
Mangrove roots anchor sediment and help soil accumulate around them. They also help build sediment through their growth and decay. Many organisms live among mangrove roots. The root system provides shelter and a place to feed on fallen leaves and other material. Crabs, conchs, and other shellfish are abundant in mangrove swamps. Saltwater swamps are also home to a huge variety of birds. Mangrove roots and branches provide excellent nesting site s.
Saltwater swamps are home to seabirds, such as gulls, as well as freshwater birds, such as herons. The abundance of plants, insects, and small animals provides food for these birds, whose droppings help fertilize the swamp. The Sundarbans, a saltwater swamp in India and Bangladesh, has the largest mangrove forest in the world. Located on mud flat s near the delta of the Ganges River, the area is saturated in freshwater.
The Sundarbans also experience strong tides from the Indian Ocean. The biodiversity of the Sundarbans stretches from tiny algae and moss to Bengal tigers. Dozens, perhaps hundreds, of different species of mangrove trees thrive in the Sundarbans. In drier areas of the swamp, palms and grasses grow. Insects such as bees build hives in the trees.
In fact, harvesting honey has been a major economic activity in the Sundarbans for centuries. Bees and other insects are one of the main food sources for tropical birds in the area. Storks, ibises, and herons nest in the high branches of mangrove and palm trees.
Smaller birds such as kingfishers and pigeons roost in shrubs. Many reptiles and amphibians live in and around the swamp, including frogs, toads, turtles, and snakes. Some of the snakes of the Sundarbans, such as the Indian python, regularly grow up to 3 meters 10 feet long.
Monitor lizards and crocodiles, also native to the Sundarbans, are even larger. The large reptiles of the Sundarbans regularly prey on mammals such as deer, boar, mongooses, and monkeys. However, the most famous predator of the Sundarbans is the Bengal tiger, an endangered species. Bengal tigers are apex predator s—human beings are their only natural predator.
In the Sundarbans, Bengal tigers swim in the swampy water and climb trees. The cats, which can grow to kilograms pounds , have been known to attack people in the swamp. Scientists and honey collectors are especially at risk. Marshes North and south of the tropics, swamps give way to marshes. These wetlands form a flat, grassy fringe near river mouths, in bays, and along coastlines. Many are alternately flooded and exposed by the movement of tides.
Like swamps, marshes are often divided into freshwater and saltwater categories. Freshwater Marshes Freshwater marshes, often found hundreds of kilometers from the coast, are dominated by grasses and aquatic plants.
These marshes often develop around lakes and streams. Many freshwater marshes lie in the prairie pothole region of North America, the heart of which extends from central Canada through the northern Midwest of the United States. Prairie potholes are bowl-shaped depressions left by chunks of glacial ice buried in the soil during the most recent ice age. When the ice melted, muddy water filled the potholes.
Fertile soil and a temperate climate make these marshes some of the richest in the world. For this reason, many prairie potholes have been drained and the land used for agriculture. Thousands of migratory birds depend on the remaining prairie potholes as they travel from the Arctic to more temperate climates every year.
Farther south, freshwater marshes form much of the Everglades, a huge wetland region in southern Florida. Water from Lake Okeechobee flows slowly through the Everglades on its way to the ocean. Sawgrass, cypress, and mangroves grow along its path. The muddy, slow-moving water is also home to rare types of orchid. The Everglades are known for their diversity of wildlife.
This marsh contains hundreds of species of wading birds, each of which is adapted to feed on insects, fish, clams, shrimp, or even rodents such as mice. Alligators make their nests in the dense sawgrass, and swim in the murky water. Dominated by grasses, they provide food and shelter for algae, fungi, shellfish, fish, amphibians, and reptiles. Wading birds and other animals feed on the vegetation and abundant insects.
The warm saltwater marshes of northern Australia are influenced by the tides of the Indian and Pacific oceans. They often overlap with the freshwater marshes of rivers, such as the Jardine. A few mangrove trees may dot saltwater marshes, but they are dominated by grasses and a layer of algae called an algal mat.
This algal mat is home to many insects and amphibians. Some of these birds nest in the shrubs and prey on insects and fish in the area. Others are migratory, only visiting the marsh when their home ranges become too cold or dry to support life. These enormous reptiles often spend the wet season in freshwater swamps and rivers, and migrate to saltwater marshes in the dry season. Many Australian beaches have strict warnings to swimmers during certain seasons, because saltwater crocodiles are a threat to people as well.
Bogs Swamps and marshes are generally found in warm climates. Most of the Everglades have been reclaimed as agricultural land, mostly sugar plantations. Federal and state authorities drained much of the wetlands at the delta of the Mississippi River in Louisiana as part of a massive system of river management. When Hurricane Katrina blew in from the Gulf of Mexico in , the spongy swamp that traditionally protected the city of New Orleans from destructive weather patterns was diminished.
The city was hit full force with a Category 3 hurricane. Eradicating swampland also threatens economic activity. Two-thirds of the fish and shellfish that are commercially harvested worldwide are linked with wetlands.
From Brazils varzeas, or freshwater swamps surrounding the Amazon River, to saltwater swamps near the Florida Keys, commercially valuable fish species that depend on wetlands are threatened with extinction. In the early s, governments began enacting laws recognizing the enormous value of swamps and other wetlands.
In some parts of the United States, it is now against the law to alter or destroy swamps. Through management plans and stricter laws, people are trying to protect remaining swamps and to re-create them in areas where they have been destroyed.
Photograph by Joseph Guillory , My Shot. Pogo One of the most important American satires of the 20th century took place in the Georgia section of the Okefenokee Swamp. Pogo , created by writer and artist Walt Kelly, was a comic strip that ran from During that time, the comic satirized American politicians like Sen.
Joseph McCarthy as a character called "Simple J. Pogo 's characters were animals native to the Okefenokee Swamp: alligators, owls, skunks, and the title character, Pogo, an opossum. During the first Earth Day, in , Pogo looked out on his garbage-infested swamp home and sighed, "We have met the enemy, and he is us. Okefenokee Swamp Okefenokee is a Native American word that means "trembling earth. Coal From Swamps Ancient swamps are a source of the fossil fuel coal.
Coal is formed from plants that died millions of years ago. The plant matter settled in layers at the bottom of swamps, where lack of oxygen kept it from decaying completely. Over time, pressure from accumulating layers caused the vegetation to harden, or fossilize, into coal.
For centuries, coal has been burned and used as fuel. Deposits of this fossil fuel can be found on every continent. Everglades, a vast swampy region flowing south of Lake Okeechobee in the U.
Spanish moss is not a moss. Also called a storm tide. The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. The Rights Holder for media is the person or group credited. Caryl-Sue, National Geographic Society. Dunn, Margery G. For information on user permissions, please read our Terms of Service.
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Climate describes the average weather conditions of a particular place over a 30 year period. All places on earth have their own climates. Different from weather events, which are short-term and temporary phenomenon, climates are usually steady and predictable, and shape how organisms and human civilizations evolve and adapt in any given region.
However, climates are not always permanent, and can change drastically due to human activity. Explore the world's climates and how they affect local regions and the planet with this curated collection of resources.
A biome is an area classified according to the species that live in that location. Abiotic factors in wetlands are nonliving factors affecting wetlands ecosystems.
Wetlands abiotic factors include water itself and its varying sources, physiochemistry such as water and soil chemistry, hydrology or the affect of flooding and available oxygen. Weather is the abiotic factor that most prominently affects wetlands.
In addition to precipitation, weather affects wetlands via storm winds and the currents made by them in larger bodies of water adjacent to wetlands. The affect of tides is another abiotic factor of wetlands. Topography and water level affects wetlands as well. Other abiotic factors of wetlands include sedimentation, erosion, turbidity water clarity , nutrients, alkalinity, temperature and physical dynamics such as ice scouring in colder climates.
Climate itself hugely impacts wetlands. Another major abiotic factor is human intrusion via land use, agriculture, shipping and urban development. Wetlands provide extraordinary wildlife diversity. The dominant wetlands wildlife includes fishes and crustaceans, migrating birds and waterfowl, and some mammal species such as:.
Wetlands serve as spawning and nursery grounds for many fish. Turtles, frogs, snakes, and other reptiles and amphibians call wetlands home. Many of these animals provide food for other animals and for people. A number of endangered and threatened wildlife species reside in wetlands.
Dominant wildlife in wetlands, whether they are birds, mammals, fish or invertebrates, rely upon the primary producers like aquatic vegetation to survive. The dominant wetlands wildlife species ensure food webs remain intact both near and far from wetlands. Wetland ecology represents a balance between the species that live in wetlands and the environment around them. Hydrology affects every aspect of wetland ecology. Flooding shapes the chemical and physical characteristics of wetlands and how much oxygen exists in them.
When this delicate balance unravels, wetlands and their denizens suffer. Pollution disrupts the chemical balance of wetlands that plants and animals depend upon to survive. Wetlands provide flood control, storm barriers, clean water and aquifer restoration.
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