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56-896: Mandora Marsh , also known as Mandora Salt Marsh , is a complex and diverse wetland system in Western Australia close to Eighty Mile Beach , and included in the Eighty Mile Beach Ramsar Site. It lies at the western edge of the Great Sandy Desert bioregion and within the Mandora Station pastoral lease . The marsh is part of the 3337 km Mandora Marsh and Anna Plains Important Bird Area , identified as such by BirdLife International because of its importance for supporting large numbers of waders and waterbirds . Mandora Marsh has formed over thousands of years on what used to be

112-463: A mangrove -lined watercourse about 5 km long and 20 m wide. It holds permanent water and appears to be fed by a series of soaks . Despite its alternative name, as well as its saline wetlands Mandora Marsh includes a number of permanent or almost permanent freshwater swamps supplied by springs along the southern side of the two main lakes. The springs are usually formed of a central, raised mound, 2–3 m high, of saturated peat , supporting

168-711: A sink or a source of carbon, depending on the specific wetland. If they function as a carbon sink, they can help with climate change mitigation . However, wetlands can also be a significant source of methane emissions due to anaerobic decomposition of soaked detritus , and some are also emitters of nitrous oxide . Humans are disturbing and damaging wetlands in many ways, including oil and gas extraction , building infrastructure, overgrazing of livestock , overfishing , alteration of wetlands including dredging and draining, nutrient pollution , and water pollution . Wetlands are more threatened by environmental degradation than any other ecosystem on Earth, according to

224-479: A 27-year hiatus there were two instances of successful breeding in Southern England in 2014. 13 young were fledged in southern England in 2017. Four chicks were successfully fledged in northern England in 2022; this is believed to be the most northerly breeding success for the black-winged stilt. These birds pick up their food from sand or water. They eat mainly insects and crustaceans. The nest site

280-402: A frequency and duration to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions. Wetlands generally included swamps, marshes, bogs, and similar areas.' For each of these definitions and others, regardless of the purpose, hydrology is emphasized (shallow waters, water-logged soils). The soil characteristics and

336-409: A mixture of Melaleuca and Sesbania trees, with mangroves appearing at the saline and brackish springs. The springs vary in size from 0.1 to several hectares; each spring's mound is generally surrounded by a moat, varying from a maximum depth of 50 cm to isolated shallow pools or just wet soil. Many springs also support small stands of cumbungi with the understories of some dominated by

392-1259: A polar climate, wetland temperatures can be as low as −50 °C (−58 °F). Peatlands in arctic and subarctic regions insulate the permafrost , thus delaying or preventing its thawing during summer, as well as inducing its formation. The amount of precipitation a wetland receives varies widely according to its area. Wetlands in Wales , Scotland , and western Ireland typically receive about 1,500 mm (59 in) per year. In some places in Southeast Asia , where heavy rains occur, they can receive up to 10,000 mm (390 in). In some drier regions, wetlands exist where as little as 180 mm (7.1 in) precipitation occurs each year. Temporal variation: Surface flow may occur in some segments, with subsurface flow in other segments. Wetlands vary widely due to local and regional differences in topography , hydrology , vegetation , and other factors, including human involvement. Other important factors include fertility, natural disturbance, competition, herbivory , burial and salinity. When peat accumulates, bogs and fens arise. The most important factor producing wetlands

448-540: A portion of the overall water cycle, which also includes atmospheric water (precipitation) and groundwater . Many wetlands are directly linked to groundwater and they can be a crucial regulator of both the quantity and quality of water found below the ground. Wetlands that have permeable substrates like limestone or occur in areas with highly variable and fluctuating water tables have especially important roles in groundwater replenishment or water recharge. Substrates that are porous allow water to filter down through

504-425: A protective barrier to coastal shoreline. Mangroves stabilize the coastal zone from the interior and will migrate with the shoreline to remain adjacent to the boundary of the water. The main conservation benefit these systems have against storms and storm surges is the ability to reduce the speed and height of waves and floodwaters. Black-winged stilt The black-winged stilt ( Himantopus himantopus )

560-422: A strong influence on wetland water chemistry, particularly in coastal wetlands and in arid and semiarid regions with large precipitation deficits. Natural salinity is regulated by interactions between ground and surface water, which may be influenced by human activity. Carbon is the major nutrient cycled within wetlands. Most nutrients, such as sulfur , phosphorus , carbon , and nitrogen are found within

616-410: A unique kind of wetland where lush plant growth and slow decay of dead plants (under anoxic conditions) results in organic peat accumulating; bogs, fens, and mires are different names for peatlands. Variations of names for wetland systems: Some wetlands have localized names unique to a region such as the prairie potholes of North America's northern plain, pocosins , Carolina bays and baygalls of

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672-515: A wetland is "an ecosystem that arises when inundation by water produces soils dominated by anaerobic and aerobic processes, which, in turn, forces the biota, particularly rooted plants, to adapt to flooding". Sometimes a precise legal definition of a wetland is required. The definition used for regulation by the United States government is: 'The term "wetlands" means those areas that are inundated or saturated by surface or ground water at

728-422: A wetland system includes its plants ( flora ) and animals ( fauna ) and microbes (bacteria, fungi). The most important factor is the wetland's duration of flooding. Other important factors include fertility and salinity of the water or soils. The chemistry of water flowing into wetlands depends on the source of water, the geological material that it flows through and the nutrients discharged from organic matter in

784-403: A wetland) affects hydro-periods (temporal fluctuations in water levels) by controlling the water balance and water storage within a wetland. Landscape characteristics control wetland hydrology and water chemistry. The O 2 and CO 2 concentrations of water depend upon temperature , atmospheric pressure and mixing with the air (from winds or water flows). Water chemistry within wetlands

840-535: A whitish line in flight. The breeding habitat of all these stilts is marshes , shallow lakes and ponds . Some populations are migratory and move to the ocean coasts in winter; those in warmer regions are generally resident or short-range vagrants . In Europe , the black-winged stilt is a regular spring overshoot vagrant north of its normal range, occasionally remaining to breed in northern European countries. Pairs successfully bred in Britain in 1987, and after

896-558: A whole. To replace these wetland ecosystem services , enormous amounts of money would need to be spent on water purification plants, dams, levees, and other hard infrastructure, and many of the services are impossible to replace. Floodplains and closed-depression wetlands can provide the functions of storage reservoirs and flood protection. The wetland system of floodplains is formed from major rivers downstream from their headwaters . "The floodplains of major rivers act as natural storage reservoirs, enabling excess water to spread out over

952-594: A wide area, which reduces its depth and speed. Wetlands close to the headwaters of streams and rivers can slow down rainwater runoff and spring snowmelt so that it does not run straight off the land into water courses. This can help prevent sudden, damaging floods downstream." Notable river systems that produce wide floodplains include the Nile River , the Niger river inland delta, the Zambezi River flood plain,

1008-543: Is a widely distributed, very long-legged wader in the avocet and stilt family Recurvirostridae . Its scientific name , Himantopus himantopus , is sometimes used to generalize a single, almost cosmopolitan species . Alternatively, it is restricted to the form that is widespread in Europe, Asia and Africa, which equals the nominate group of H. himantopus sensu lato . Meanwhile, the black-necked ( H. mexicanus ) and white-backed stilts ( H. melanurus ) both inhabit

1064-440: Is determined by the pH , salinity , nutrients, conductivity , soil composition, hardness , and the sources of water. Water chemistry varies across landscapes and climatic regions. Wetlands are generally minerotrophic (waters contain dissolved materials from soils) with the exception of ombrotrophic bogs that are fed only by water from precipitation. Because bogs receive most of their water from precipitation and humidity from

1120-412: Is hydrology, or flooding . The duration of flooding or prolonged soil saturation by groundwater determines whether the resulting wetland has aquatic, marsh or swamp vegetation . Other important factors include soil fertility, natural disturbance, competition, herbivory , burial, and salinity. When peat from dead plants accumulates, bogs and fens develop. Wetland hydrology is associated with

1176-471: Is one of four distinct species, which sometimes are considered subspecies of H. himantopus . H. himantopus sensu lato is made up of a single species, with 5–7 subspecies, and is sometimes referred to as the common stilt . The name "black-winged stilt" refers to H. himantopus sensu stricto , with two subspecies ( H.h. himantopus from the Palearctic to South Asia , and H.h. meridionalis from

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1232-451: Is the only place in the world where both crocodiles and alligators coexist. The saltwater crocodile inhabits estuaries and mangroves. Snapping turtles also inhabit wetlands. Birds , particularly waterfowl and waders use wetlands extensively. Mammals of wetlands include numerous small and medium-sized species such as voles , bats , muskrats and platypus in addition to large herbivorous and apex predator species such as

1288-545: Is usually saturated with water". More precisely, wetlands are areas where "water covers the soil , or is present either at or near the surface of the soil all year or for varying periods of time during the year, including during the growing season". A patch of land that develops pools of water after a rain storm would not necessarily be considered a "wetland", even though the land is wet. Wetlands have unique characteristics: they are generally distinguished from other water bodies or landforms based on their water level and on

1344-486: The Afrotropical region). Adults are 33–36 cm (13–14 in) long, with long, pink legs, and a long, rather thin black bill. The birds are generally black above and white below, with a white head and neck (with a varying amount of black, species-dependent). Males have a black back, often with a greenish gloss or sheen. Females' backs have a brownish hue, contrasting with the black remiges . In populations where

1400-505: The Millennium Ecosystem Assessment from 2005. Methods exist for assessing wetland ecological health . These methods have contributed to wetland conservation by raising public awareness of the functions that wetlands can provide. Since 1971, work under an international treaty seeks to identify and protect " wetlands of international importance ." A simplified definition of wetland is "an area of land that

1456-688: The Pantanal in South America, and the Sundarbans in the Ganges - Brahmaputra delta. Wetlands contribute many ecosystem services that benefit people. These include for example water purification , stabilization of shorelines, storm protection and flood control . In addition, wetlands also process and condense carbon (in processes called carbon fixation and sequestration ), and other nutrients and water pollutants . Wetlands can act as

1512-592: The Poaceae , or true grass family, and nine introduced weeds. The most inland occurrence of mangroves in Australia is an isolated stand of grey mangroves in the eastern lake of the marsh, 60 km inland from Eighty-mile Beach. A new species of bush tomato , Solanum oligandrum , known only from the Mandora Marsh area, was first described in 2001. A total of 55 species of waterbirds have been seen at

1568-444: The atmosphere , their water usually has low mineral ionic composition. In contrast, wetlands fed by groundwater or tides have a higher concentration of dissolved nutrients and minerals. Fen peatlands receive water both from precipitation and ground water in varying amounts so their water chemistry ranges from acidic with low levels of dissolved minerals to alkaline with high accumulation of calcium and magnesium . Salinity has

1624-576: The beavers , coypu , swamp rabbit , Florida panther , jaguar , and moose . Wetlands attract many mammals due to abundant seeds, berries, and other vegetation as food for herbivores, as well as abundant populations of invertebrates, small reptiles and amphibians as prey for predators. Invertebrates of wetlands include aquatic insects such as dragonflies , aquatic bugs and beetles , midges, mosquitos , crustaceans such as crabs, crayfish, shrimps, microcrustaceans, mollusks like clams, mussels, snails and worms. Invertebrates comprise more than half of

1680-494: The fern Achrostichum speciosum . Thickets of saltwater paperbark are found where flood waters remain longest; stock watering bores have been established in these thickets and the watering troughs are used by waterbirds throughout the year. The most spectacular of the springs is Mandora Soak, a raised peat bog estimated to be 7000 years old. Some 269 species of vascular plants , from 55 families , have been collected from Mandora Salt Marsh. This includes 37 species from

1736-539: The type locality as southern Europe. The taxonomic name Himantopus comes from Greek , meaning "strap-foot" or "thong-foot". The black-winged stilt is now one of five species placed in the genus Himantopus that was introduced by the French naturalist Mathurin Jacques Brisson in 1760. The species is monotypic : no subspecies are recognised. The taxonomy of this bird is still somewhat contentious; it

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1792-557: The Americas; the pied stilt ( H. leucocephalus ) ranges from Australasia and New Zealand . Today, most sources accept between one and four actual species . The black-winged stilt was formally described in 1758 by the Swedish naturalist Carl Linnaeus in the tenth edition of his Systema Naturae . He placed it with the plovers in the genus Charadrius and coined the binomial name Charadrius himantopus . He specified

1848-639: The Okavango River inland delta, the Kafue River flood plain, the Lake Bangweulu flood plain (Africa), Mississippi River (US), Amazon River (South America), Yangtze River (China), Danube River (Central Europe) and Murray-Darling River (Australia). Groundwater replenishment can be achieved for example by marsh , swamp , and subterranean karst and cave hydrological systems. The surface water visibly seen in wetlands only represents

1904-522: The Southeastern US, mallines of Argentina, Mediterranean seasonal ponds of Europe and California, turloughs of Ireland, billabongs of Australia, among many others. Wetlands are found throughout the world in different climates. Temperatures vary greatly depending on the location of the wetland. Many of the world's wetlands are in the temperate zones , midway between the North or South Poles and

1960-502: The US, the best known classifications are the Cowardin classification system and the hydrogeomorphic (HGM) classification system. The Cowardin system includes five main types of wetlands: marine (ocean-associated), estuarine (mixed ocean- and river-associated), riverine (within river channels), lacustrine (lake-associated) and palustrine (inland nontidal habitats). Peatlands are

2016-610: The United States' commercial fish and shellfish stocks depend solely on estuaries to survive. Amphibians such as frogs and salamanders need both terrestrial and aquatic habitats in which to reproduce and feed. Because amphibians often inhabit depressional wetlands like prairie potholes and Carolina bays, the connectivity among these isolated wetlands is an important control of regional populations. While tadpoles feed on algae, adult frogs forage on insects. Frogs are sometimes used as an indicator of ecosystem health because their thin skin permits absorption of nutrients and toxins from

2072-407: The depth of water never exceeds 2 m. The eastern lake 19°47′S 121°35′E  /  19.783°S 121.583°E  / -19.783; 121.583 is separated from Walyarta by a calcrete ridge. It is a broad and braided drainage line containing islands of vegetation that floods extensively but soon dries out to a series of isolated salt and claypans. Connecting the lakes is Salt Creek,

2128-634: The equator. In these zones, summers are warm and winters are cold, but temperatures are not extreme. In subtropical zone wetlands, such as along the Gulf of Mexico , average temperatures might be 11 °C (52 °F). Wetlands in the tropics are subjected to much higher temperatures for a large portion of the year. Temperatures for wetlands on the Arabian Peninsula can exceed 50 °C (122 °F) and these habitats would therefore be subject to rapid evaporation. In northeastern Siberia , which has

2184-504: The following areas: According to the Ramsar Convention: The economic worth of the ecosystem services provided to society by intact, naturally functioning wetlands is frequently much greater than the perceived benefits of converting them to 'more valuable' intensive land use – particularly as the profits from unsustainable use often go to relatively few individuals or corporations, rather than being shared by society as

2240-468: The interface between truly terrestrial ecosystems and aquatic systems, making them inherently different from each other, yet highly dependent on both." In environmental decision-making, there are subsets of definitions that are agreed upon to make regulatory and policy decisions. Under the Ramsar international wetland conservation treaty , wetlands are defined as follows: An ecological definition of

2296-462: The known animal species in wetlands, and are considered the primary food web link between plants and higher animals (such as fish and birds). Depending on a wetland's geographic and topographic location, the functions it performs can support multiple ecosystem services , values, or benefits. United Nations Millennium Ecosystem Assessment and Ramsar Convention described wetlands as a whole to be of biosphere significance and societal importance in

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2352-497: The lower reaches and estuary of an ancient river. The main features are two large lakes which are flooded after heavy cyclonic rainfall. The westernmost Lake Walyarta 19°46′S 121°17′E  /  19.767°S 121.283°E  / -19.767; 121.283 is a claypan that extends eastwards about 30 km from the inland side of the Great Northern Highway . Although its width may reach 5 km,

2408-585: The marsh, of which at least 13 species have been recorded breeding there. Particularly common ones include black-winged stilt , whiskered tern , grey teal , white-necked heron , and great egret . Australian pelicans and black swans breed there in large numbers when floods make conditions suitable. The threatened bilby , which is specially protected by the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 , has been recorded in sandy sites within

2464-692: The marsh. Wetland Wetlands exist on every continent , except Antarctica . The water in wetlands is either freshwater , brackish or saltwater . The main types of wetland are defined based on the dominant plants and the source of the water. For example, marshes are wetlands dominated by emergent herbaceous vegetation such as reeds , cattails and sedges . Swamps are dominated by woody vegetation such as trees and shrubs (although reed swamps in Europe are dominated by reeds, not trees). Mangrove forest are wetlands with mangroves , halophytic woody plants that have evolved to tolerate salty water . Examples of wetlands classified by

2520-680: The marsh. Altogether, 22 species of mammal , 49 reptiles and six frogs have been recorded there, while a new goby species has been discovered in Salt Creek. The Mandora Marsh is of high cultural significance to the Nyangumarta people , who hold native title over the area. Cattle grazing has caused substantial deterioration in the vegetation and physical environment of the springs and Salt Creek; Saunders Spring in 1997, and Grants Spring in 2001, were fenced to limit further damage. High numbers of feral camels and cats are present in

2576-837: The plants and animals controlled by the wetland hydrology are often additional components of the definitions. Wetlands can be tidal (inundated by tides) or non-tidal. The water in wetlands is either freshwater , brackish , saline , or alkaline . There are four main kinds of wetlands – marsh , swamp , bog , and fen (bogs and fens being types of peatlands or mires ). Some experts also recognize wet meadows and aquatic ecosystems as additional wetland types. Sub-types include mangrove forests , carrs , pocosins , floodplains , peatlands, vernal pools , sinks , and many others. The following three groups are used within Australia to classify wetland by type: Marine and coastal zone wetlands, inland wetlands and human-made wetlands. In

2632-429: The soil and underlying rock into aquifers which are the source of much of the world's drinking water . Wetlands can also act as recharge areas when the surrounding water table is low and as a discharge zone when it is high. Mangroves , coral reefs , salt marsh can help with shoreline stabilization and storm protection. Tidal and inter-tidal wetland systems protect and stabilize coastal zones. Coral reefs provide

2688-537: The soil of wetlands. Anaerobic and aerobic respiration in the soil influences the nutrient cycling of carbon, hydrogen, oxygen, and nitrogen, and the solubility of phosphorus thus contributing to the chemical variations in its water. Wetlands with low pH and saline conductivity may reflect the presence of acid sulfates and wetlands with average salinity levels can be heavily influenced by calcium or magnesium. Biogeochemical processes in wetlands are determined by soils with low redox potential. The life forms of

2744-412: The soils and plants at higher elevations. Plants and animals may vary within a wetland seasonally or in response to flood regimes. There are four main groups of hydrophytes that are found in wetland systems throughout the world. Submerged wetland vegetation can grow in saline and fresh-water conditions. Some species have underwater flowers, while others have long stems to allow the flowers to reach

2800-530: The sources of water include tidal wetlands , where the water source is ocean tides ); estuaries , water source is mixed tidal and river waters; floodplains , water source is excess water from overflowed rivers or lakes; and bogs and vernal ponds , water source is rainfall or meltwater . The world's largest wetlands include the Amazon River basin , the West Siberian Plain ,

2856-406: The spatial and temporal dispersion, flow, and physio-chemical attributes of surface and ground waters. Sources of hydrological flows into wetlands are predominantly precipitation , surface water (saltwater or freshwater), and groundwater. Water flows out of wetlands by evapotranspiration , surface flows and tides , and subsurface water outflow. Hydrodynamics (the movement of water through and from

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2912-719: The surface of the water. When trees and shrubs comprise much of the plant cover in saturated soils, those areas in most cases are called swamps . The upland boundary of swamps is determined partly by water levels. This can be affected by dams Some swamps can be dominated by a single species, such as silver maple swamps around the Great Lakes . Others, like those of the Amazon basin , have large numbers of different tree species. Other examples include cypress ( Taxodium ) and mangrove swamps. Many species of fish are highly dependent on wetland ecosystems. Seventy-five percent of

2968-496: The surface. Submerged species provide a food source for native fauna, habitat for invertebrates, and also possess filtration capabilities. Examples include seagrasses and eelgrass . Floating water plants or floating vegetation are usually small, like those in the Lemnoideae subfamily (duckweeds). Emergent vegetation like the cattails ( Typha spp.), sedges ( Carex spp.) and arrow arum ( Peltandra virginica ) rise above

3024-464: The surrounding environment resulting in increased extinction rates in unfavorable and polluted environmental conditions. Reptiles such as snakes , lizards , turtles , alligators and crocodiles are common in wetlands of some regions. In freshwater wetlands of the Southeastern US, alligators are common and a freshwater species of crocodile occurs in South Florida. The Florida Everglades

3080-432: The top of the head is normally white (at least in winter), females tend to have less black on the head and neck the entire year-round, while males often have much more black, particularly in summer. This difference is not clear-cut, however, and males usually grow all-white head feathers in winter. Immature birds are grey, instead of black, and have a markedly sandy hue on their wings, with light feather fringes appearing as

3136-440: The types of plants that live within them. Specifically, wetlands are characterized as having a water table that stands at or near the land surface for a long enough period each year to support aquatic plants . A more concise definition is a community composed of hydric soil and hydrophytes . Wetlands have also been described as ecotones , providing a transition between dry land and water bodies. Wetlands exist "...at

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