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45-476: It covers a total area of about 50,000 km (19,000 sq mi). The characteristic landscape is composed of treeless plains, saline steppes and salt lakes , and includes scattered sand dunes, low, wet forests and freshwater marshes along the floodplains of the ancient rivers. It is strongly associated with traditional Hungarian breeds of domestic animal including the Hungarian Grey breed of cattle,

90-412: A chorion coating which has a brown colour. These eggs, also known as cysts, are metabolically inactive and can remain in total stasis for two years while in dry oxygen-free conditions, even at temperatures below freezing. This characteristic is called cryptobiosis , meaning "hidden life". While in cryptobiosis, brine shrimp eggs can survive temperatures of liquid air (−190 °C or −310 °F) and

135-455: A model organism for use in toxicological assays, despite the recognition that it is too robust an organism to be a sensitive indicator species . In pollution research Artemia , the brine shrimp, has had extensive use as a test organism and in some circumstances is an acceptable alternative to the toxicity testing of mammals in the laboratory. The fact that millions of brine shrimp are so easily reared has been an important help in assessing

180-571: A crucial role as a keystone species by regulating phytoplankton and bacterioplankton levels. The Artemia species also serves as an intermediate host for helminth parasites that affect migratory water birds like flamingos, grebes, gulls, shorebirds, and ducks. Vertebrates in saline lakes include certain fish and bird species, though they are sensitive to fluctuations in salinity. Many saline lakes are also alkaline, which imposes physiological challenges for fish, especially in managing nitrogenous waste excretion. Fish species vary by lake; for instance,

225-580: A higher concentration of salt than sea water ; such lakes can also be termed hypersaline lake , and may also be pink lakes on account of their color. An alkalic salt lake that has a high content of carbonate is sometimes termed a soda lake . Salt lakes are classified according to salinity levels. The formation of these lakes is influenced by processes such as evaporation and deposition. Salt lakes face serious conservation challenges due to climate change, pollution and water diversion. The primary method of classification for salt lakes involves assessing

270-405: A segmented body to which is attached broad leaf-like appendages . The body usually consists of 19 segments, the first 11 of which have pairs of appendages, the next two which are often fused together carry the reproductive organs, and the last segments lead to the tail. The total length is usually about 8–10 millimetres (0.31–0.39 in) for the adult male and 10–12 mm (0.39–0.47 in) for

315-400: A small percentage can survive above boiling temperature (105 °C or 221 °F) for up to two hours. Once placed in briny (salt) water, the eggs hatch within a few hours. The nauplius larvae are less than 0.4 mm in length when they first hatch. Parthenogenesis is a natural form of reproduction in which growth and development of embryos occur without fertilisation . Thelytoky

360-710: Is a hyposaline lake. Mesosaline lakes have a salinity level ranging from 3 to 35 g/L. An example of a mesosaline lake is Redberry Lake in Saskatchewan, Canada . Hypersaline lakes possess salinities greater than 35 g/L, often reaching levels that can exceed 200 g/L. The extreme salinity levels create harsh conditions that limit the diversity of life, primarily supporting specialized organisms such as halophilic bacteria and certain species of brine shrimp . These lakes can have high concentrations of sodium salts and minerals, such as lithium, making such lakes vulnerable to mining interests. Hypersaline lakes can be found in

405-505: Is a particular form of parthenogenesis in which the development of a female individual occurs from an unfertilised egg. Automixis is a form of thelytoky, but there are different kinds of automixis. The kind of automixis relevant here is one in which two haploid products from the same meiosis combine to form a diploid zygote . Diploid Artemia parthenogenetica reproduce by automictic parthenogenesis with central fusion (see diagram) and low but nonzero recombination. Central fusion of two of

450-587: Is achieved by the rhythmic beating of the appendages acting in pairs. Respiration occurs on the surface of the legs through fibrous, feather-like plates (lamellar epipodites). Males differ from females by having the second antennae markedly enlarged, and modified into clasping organs used in mating. Adult female brine shrimp ovulate approximately every 140 hours. In favourable conditions, the female brine shrimp can produce eggs that almost immediately hatch. While in extreme conditions, such as low oxygen level or salinity above 150‰, female brine shrimp produce eggs with

495-501: Is not limited to the Aral Sea; salt lakes around the world are shrinking due to excessive water diversion, dam construction, pollution, urbanization, and rising temperatures associated with climate change. The resulting declines cause severe disruptions to local ecosystems and biodiversity, degrades the environment, threatens economic stability, and displaces communities dependent on these lakes for resources and livelihood. In Utah, if

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540-547: The Artemia genome was assembled and annotated , revealing a genome containing an unequaled 58% of repeats , genes with unusually long introns and adaptations unique to the extremophilic nature of Artemia in high salt and low oxygen environments. These adaptations include a unique energy-intensive endocytosis -based salt excretion strategy resembling salt excretion strategies of plants, as well as several survival strategies for extreme environments it has in common with

585-446: The Artemia to produce dormant eggs, known as cysts , has led to extensive use of Artemia in aquaculture . The cysts may be stored indefinitely and hatched on demand to provide a convenient form of live feed for larval fish and crustaceans . Nauplii of the brine shrimp Artemia constitute the most widely used food item, and over 2,000 metric tons (2,200 short tons) of dry Artemia cysts are marketed worldwide annually with most of

630-606: The Mangalitsa breed of woolly pig, the Nonius breed of horse and the Racka breed of horned sheep, and also with the traditions of the csikós mounted herdsmen. The adjective puszta has meanings including 'abandoned', 'bare', 'bleak', 'deserted' and 'uninhabited'. A large, mostly treeless, grassy plain which can only be used for grazing livestock, as the poor quality of the soil makes it unsuitable for crop production. From

675-720: The McMurdo Dry Valleys in Antarctica, where salinity can reach ≈440‰. Salt lakes form through complex chemical, geological, and biological processes, influenced by environmental conditions like high evaporation rates and restricted water outflow. As water carrying dissolved minerals ( sodium , potassium , and magnesium ) enters these basins, it gradually evaporates, concentrating these minerals until they precipitate as salt deposits. Then, specific ions interact under controlled temperatures, which leads to solid-solution formation and salt crystal deposition within

720-540: The Mediterranean area about 5.5  million years ago , around the time of the Messinian salinity crisis . The Laboratory of Aquaculture & Artemia Reference Center at Ghent University possesses the largest known Artemia cyst collection, a cyst bank containing over 1,700 Artemia population samples collected from different locations around the world. Artemia is a typical primitive arthropod with

765-716: The United States Fish and Wildlife Service to add A. monica to the endangered species list under the Endangered Species Act (1973). The diversion of water by the Los Angeles Department of Water and Power resulted in rising salinity and concentration of sodium hydroxide in Mono Lake. Despite the presence of trillions of brine shrimp in the lake, the petition contended that the increase in pH would endanger them. The threat to

810-573: The naupliar eye , is situated anteriorly in the centre of the head and is the only functional optical sense organ in the nauplii, which is functional until the adult stage. Brine shrimp can tolerate any levels of salinity from 25 ‰ to 250‰ (25–250 g/L), with an optimal range of 60‰–100‰, and occupy the ecological niche that can protect them from predators. Physiologically, optimal levels of salinity are about 30–35‰, but due to predators at these salt levels, brine shrimp seldom occur in natural habitats at salinities of less than 60–80‰. Locomotion

855-524: The 10th century AD from Lake Urmia , Iran , with an example called by an Iranian geographer an "aquatic dog", although the first unambiguous record is the report and drawings made by Schlösser in 1757 of animals from Lymington , England . Artemia populations are found worldwide, typically in inland saltwater lakes, but occasionally in oceans. Artemia are able to avoid cohabiting with most types of predators, such as fish, by their ability to live in waters of very high salinity (up to 25%). The ability of

900-474: The Great Salt Lake is not conserved, the state could face potential economic and public health crises, with consequences for air quality, local agriculture, and wildlife. According to “Utah’s Great Salt Lake Strike Team”, in order increase the lake's level within the next 30 years, see average inflows must increase by 472,00 acre-feet per year, which is about a 33% increase in the amount that has reached

945-775: The Mediterranean region. Among the highly localized species are A. urmiana from Lake Urmia in Iran. Once abundant, the species has drastically declined due to drought, leading to fears that it was almost extinct. However, a second population of this species has recently been discovered in the Koyashskoye Salt Lake , Ukraine . A. monica , the species commonly known as Mono Lake brine shrimp, can be found in Mono Lake , Mono County, California . In 1987, Dennis D. Murphy from Stanford University petitioned

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990-580: The Russian Bion-3 ( Cosmos 782 ), Bion-5 ( Cosmos 1129 ), Foton 10, and Foton 11 flights. Some of the Russian flights carried European Space Agency experiments. On Apollo 16 and Apollo 17, the cysts traveled to the Moon and back. Cosmic rays that passed through an egg would be detected on the photographic film in its container. Some eggs were kept on Earth as experimental controls as part of

1035-489: The Salton Sea is home to species such as carp, striped mullet, humpback sucker, and rainbow trout. Stratification in salt lakes occurs as a result of the unique chemical and environmental processes that cause water to separate into layers based on density . In these lakes, high rates of evaporation often concentrate salts, leading to denser, saltier water sinking to the lake's bottom, while fresher water remains nearer

1080-456: The brain; instead, local nervous system ganglia may control some regulation or synchronisation of these functions. Autotomy, the voluntary shedding or dropping of parts of the body for defence, is also controlled locally along the nervous system. Artemia have two types of eyes. They have two widely separated compound eyes mounted on flexible stalks. These compound eyes are the main optical sense organ in adult brine shrimps. The median eye, or

1125-510: The chemical composition of the water within the lakes, specifically its salinity, pH , and the dominant ions present. Subsaline lakes have a salinity lower than that of seawater but higher than freshwater , typically ranging from 0.5 to 3 grams per liter (g/L). Hyposaline lakes exhibit salinities from 0.5 to 3 g/L, which allows for the presence of freshwater species along with some salt-tolerant aquatic organisms. Lake Alchichica in Mexico

1170-734: The cyst. Wild brine shrimp eat microscopic planktonic algae . Cultured brine shrimp can also be fed particulate foods including yeast , wheat flour , soybean powder or egg yolk . Artemia comprises sexually reproducing, diploid species and several obligate parthenogenetic Artemia populations consisting of different clones and ploidies (2n->5n). Several genetic maps have been published for Artemia . The past years, different transcriptomic studies have been performed to elucidate biological responses in Artemia , such as its response to salt stress, toxins, infection and diapause termination. These studies also led to various fully assembled Artemia transcriptomes . Recently,

1215-583: The cysts being harvested from the Great Salt Lake in Utah. In addition, the resilience of Artemia makes them ideal animals for running biological toxicity assays and it has become a model organism used to test the toxicity of chemicals. Breeds of Artemia are sold as novelty gifts under the marketing name Sea-Monkeys . The brine shrimp Artemia comprises a group of seven to nine species very likely to have diverged from an ancestral form living in

1260-511: The effects of a large number of environmental pollutants on the shrimps under well controlled experimental conditions. Overall, brine shrimp are abundant, but some populations and localized species do face threats, especially from habitat loss to introduced species . For example, A. franciscana of the Americas has been widely introduced to places outside its native range and is often able to outcompete local species, such as A. salina in

1305-663: The extremophilic tardigrade . Fish farm owners search for a cost-effective, easy to use, and available food that is preferred by the fish. From cysts, brine shrimp nauplii can readily be used to feed fish and crustacean larvae just after a one-day incubation . Instar I (the nauplii that just hatched and with large yolk reserves in their body) and instar II nauplii (the nauplii after first moult and with functional digestive tracts) are more widely used in aquaculture, because they are easy for operation, rich in nutrients, and small, which makes them suitable for feeding fish and crustacean larvae live or after drying. Artemia found favor as

1350-480: The female, but the width of both sexes, including the legs, is about 4 mm (0.16 in). The body of Artemia is divided into head, thorax , and abdomen. The entire body is covered with a thin, flexible exoskeleton of chitin to which muscles are attached internally and which is shed periodically. In female Artemia, a moult precedes every ovulation . For brine shrimp, many functions, including swimming, digestion and reproduction are not controlled through

1395-426: The haploid products of meiosis (see diagram) tends to maintain heterozygosity in transmission of the genome from mother to offspring, and to minimise inbreeding depression . Low crossover recombination during meiosis likely restrains the transition from heterozygosity to homozygosity over successive generations. In their first stage of development, Artemia do not feed but consume their own energy reserves stored in

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1440-479: The lack of vertical mixing. Extremophiles , including specific bacteria and archaea , inhabit the hypersaline and oxygen-deficient zones at lower depths. Bacteria and archaea, for example, rely on alternative metabolic processes that do not depend on oxygen. These microorganisms play a critical role in nutrient cycling within salt lakes, as they break down organic material and release by-products that support other microbial communities. Due to limited biodiversity,

1485-400: The lake bed. This cycle of evaporation and deposition is the main process to the unique saline environment that characterizes a salt lake. Environmental factors further shape the composition and formation of salt lakes. Seasonal variations in temperature and evaporation drive mineral saturation and promote salt crystallization . In dry regions, water loss during warmer seasons concentrates

1530-428: The lake in recent years. Water conservation is viewed as being the most cost-effective and practical strategy to save salt lakes like the Great Salt Lake. Implementing strong water management policies, improving community awareness, and ensuring the return of water flow to these lakes are additional ways that may restore ecological balance. Other proposed methods of maintaining lake levels include cloud seeding and

1575-475: The lake's chemistry, supporting only specialized microbial life adapted to extreme environments with high salinity and low oxygen levels. The restricted vertical mixing limits nutrient cycling , creating a favorable ecosystem for halophiles (salt-loving organisms) that rely on these saline conditions for stability and balance. The extreme conditions within stratified salt lakes have a profound effect on aquatic life , as oxygen levels are severely limited due to

1620-548: The lake's salts. This creates a dynamic environment where seasonal shifts affect the salt lake's mineral layers, contributing to its evolving structure and composition. Groundwater rich in dissolved ions often serve as primary mineral sources that, combined with processes like evaporation and deposition, contribute to salt lake development. Salt lakes host a diverse range of animals, despite high levels of salinity acting as significant environmental constraints. Increased salinity worsens oxygen levels and thermal conditions, raising

1665-504: The lake's water levels was addressed by a revision to California State Water Resources Control Board 's policy, and the US Fish and Wildlife Service found on 7 September 1995 that the Mono Lake brine shrimp did not warrant listing. Scientists have taken the eggs of brine shrimp to outer space to test the impact of radiation on life. Brine shrimp cysts were flown on the U.S. Biosatellite 2 , Apollo 16 , and Apollo 17 missions, and on

1710-622: The late Pleistocene era the landscape of the Alföld or Great Hungarian Plain consisted in large part of arid alkaline grasslands devoid of trees – the puszta. The extent of the puszta over much of the Alföld was drastically reduced by the extensive drainage and irrigation works carried out during the nineteenth century, and it survives principally in the Hortobágy National Park , established in 1972 in eastern Hungary and centred on

1755-400: The mitigation of dust transmission hotspots. Note: Some of the following are also partly fresh and/or brackish water. Brine shrimp Artemia is a genus of aquatic crustaceans also known as brine shrimp , Aqua Dragons or sea monkeys . It is the only genus in the family Artemiidae . The first historical record of the existence of Artemia dates back to the first half of

1800-412: The region also produces poultry and foie gras . Three hundred species of birds are found here. Salt lake A salt lake or saline lake is a landlocked body of water that has a concentration of salts (typically sodium chloride ) and other dissolved minerals significantly higher than most lakes (often defined as at least three grams of salt per liter). In some cases, salt lakes have

1845-417: The restrictive environment limits biodiversity , allowing only specially adapted life forms to survive, which creates unique, highly specialized ecosystems that are distinct from freshwater or less saline habitats. Salt lakes declined worldwide in recent years. The Aral Sea , once of the largest saline lakes with a surface area of 67,499 km in 1960, diminished to approximately 6,990 km in 2016. This trend

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1890-462: The surface. These seasonal changes influence the lake's structure, making stratification more pronounced during warmer months due to increasing evaporation, which drives separation between saline and fresher layers in the lake, leading a phenomenon known as meromixis (meromictic state), primarily prevents oxygen from penetrating the deeper layers and create the hypoxic (low oxygen) or anoxic (no oxygen) zones. This separation eventually influenced

1935-553: The tests. Also, as the take-off in a spacecraft involves a lot of shaking and acceleration , one control group of egg cysts was accelerated to seven times the force of gravity and vibrated mechanically from side to side for several minutes so that they could experience the same violence of a rocket take-off. About 400 eggs were in each experimental group. All the egg cysts from the experiment were then placed in salt water to hatch under optimum conditions. The results showed A. salina eggs are highly sensitive to cosmic radiation; 90% of

1980-588: The village of Hortobágy in Hajdú-Bihar County . The climate is continental. Landscape is widely cultivated, the original Puszta landscape now being found only in a few places, for example in Hortobágy National Park . Most of Hungary's vegetable and grain crops are grown on the Great Plain. The region has a sandy soil and is sunny; the city of Szeged is often called City of Sunshine ( Napfény városa ). In addition to cattle, sheep, and pigs,

2025-433: The water's density and viscosity , which demands greater energy for animal movement. Despite these challenges, salt lakes support biota adapted to such conditions with specialized physiological and biochemical mechanisms. Common salt lake invertebrates include various parasites, with around 85 parasite species found in saline waters, including crustaceans and monogeneans . Among them, the filter-feeding brine shrimp plays

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