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83-574: The Murray–Darling Basin is a large geographical area in the interior of southeastern Australia, encompassing the drainage basin of the tributaries of the Murray River , Australia's longest river , and the Darling River , a right tributary of the Murray and Australia's third-longest river. The Basin, which includes six of Australia's seven longest rivers and covers around one-seventh of

166-428: A "Eurasian" carp. Carp have long been an important food fish to humans. Several species such as the various goldfish ( Carassius auratus ) breeds and the domesticated common carp variety known as koi ( Cyprinus rubrofuscus var. "koi" ) have been popular ornamental fishes. As a result, carp have been introduced to various locations, though with mixed results. Several species of carp are considered invasive species in

249-646: A domesticated varieties of common carp and Amur carp ( Cyprinus rubrofuscus ) that have been selectively bred for color. The common carp was introduced from China to Japan, where selective breeding in the 1820s in the Niigata region resulted in koi. In Japanese culture, koi are treated with affection, and seen as good luck. They are popular in other parts of the world as outdoor pond fish. A long tradition of common carp exists in Chinese culture and literature. A popular lyric circulating as early as 2,000 years ago in

332-454: A drainage basin, and there are different ways to interpret that data. In the unlikely event that the gauges are many and evenly distributed over an area of uniform precipitation, using the arithmetic mean method will give good results. In the Thiessen polygon method, the drainage basin is divided into polygons with the rain gauge in the middle of each polygon assumed to be representative for

415-540: A drainage boundary is referred to as watershed delineation . Finding the area and extent of a drainage basin is an important step in many areas of science and engineering. Most of the water that discharges from the basin outlet originated as precipitation falling on the basin. A portion of the water that enters the groundwater system beneath the drainage basin may flow towards the outlet of another drainage basin because groundwater flow directions do not always match those of their overlying drainage network. Measurement of

498-450: A fairly confident estimate has been made of these animals and the current status of their population. The study found that there were: Historical records show that the previous abundances of fish provided a reliable food source. The bountiful fish became concentrated when the early stages of a flood left shallow water across the floodplain. Today, roughly 24 native freshwater fish and another 15-25 marine and estuarine species are existent in

581-523: A high feed conversion rate . Over 50% of the total aquaculture production of carp in China has now converted to Jian carp. Carp, along with many of their cyprinid relatives, are popular ornamental aquarium and pond fish. Ornamental goldfish were originally domesticated from their wild form, a dark greyish-brown carp native to Asia, but may have been influenced by Carassius carassius and Carassius gibelio . They were first bred for color in China over

664-528: A high degree of eloquence to the Japanese people, thus creating a level of respect and appreciation for the Koi. With Koi fish being at the forefront of a lot of Japanese art, it is common to find modern depictions of Koi in paintings, home art, murals, and even tattoos. To many people, Koi fish strongly represent Samurai warriors, as they are able to be seen swimming upwards against a rivers current, symbolizing

747-426: A point where surface water is lost underground . Drainage basins are similar but not identical to hydrologic units , which are drainage areas delineated so as to nest into a multi-level hierarchical drainage system . Hydrologic units are defined to allow multiple inlets, outlets, or sinks. In a strict sense, all drainage basins are hydrologic units but not all hydrologic units are drainage basins. About 48.71% of

830-516: A problem because they feed by sucking gravel from the riverbed and taking all the edible material off it, before returning the rest to the water. This stirs up all the sediment, reducing the quality of the water. A project for developing daughterless carp shows promise for eliminating carp from the river system. Cane toads have entered the upper reaches of the Darling Basin and there are several reports of individuals being found further down

913-479: A quarter of the Basin lays in the state, the commission was an advisory body with no authority for enforcement of provisions. For a long time the commission was only concerned with water quantity until salinity became a problem. This led to minor reforms in 1982 in which water quality became part of the commission's responsibilities. However, it was soon recognised that a new organisational structure which considered

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996-402: A thousand years ago. Due to selective breeding, goldfish have been developed into many distinct breeds, and are found in various colors, color patterns, forms and sizes far different from those of the original carp. Goldfish were kept as ornamental fish in China for thousands of years before being introduced to Japan in 1603, and to Europe in 1611. Nishikigoi , better known simply as koi, are

1079-514: Is 3,375 kilometres (2,097 mi) in length, with the Murray River being 2,508 km (1,558 mi) long. Most of the 1,061,469 km (409,835 sq mi) basin is flat, low-lying and far inland, and receives little direct rainfall. The many rivers it contains tend to be long and slow-flowing, and carry a volume of water that is large only by Australian standards. The Snowy Mountains Scheme provides some security of water flows to

1162-482: Is a waterfall called the Dragon Gate . It is said that if certain carp called yulong can climb the cataract, they will transform into dragons. Every year in the third month of spring, they swim up from the sea and gather in vast numbers in the pool at the foot of the falls. It used to be said that only 71 could make the climb in any year. When the first succeeded, then the rains would begin to fall. This Dragon Gate

1245-528: Is one of the physiographic provinces of the larger East Australian Basins division, and encompasses the smaller Naracoorte Platform and Encounter Shelf physiographic sections. Total water flow in the Murray–Darling Basin 1885 to the present has averaged around 24,000 gigalitres (24,000  hm ; 19,000,000  acre⋅ft ) per year. This is the lowest rate of the world's major river systems. About 6.0 percent of Australia's total rainwater falls into

1328-487: Is referred to as " watershed management ". In Brazil , the National Policy of Water Resources, regulated by Act n° 9.433 of 1997, establishes the drainage basin as the territorial division of Brazilian water management. When a river basin crosses at least one political border, either a border within a nation or an international boundary, it is identified as a transboundary river . Management of such basins becomes

1411-691: Is said about them. Other famous Dragon Gates are on the Wei River where it passes through the Lung Sheu Mountains and at Tsin in Shanxi Province. The fish's jumping feature is set in such a proverbial idiom as " Liyu (Carp) jumps over the Dragon Gate ( Chinese : 鲤跃龙门 )," an idiom that conveys a vivid image symbolizing a sudden uplifting in one's social status, as when one ascends into the upper society or has found favor with

1494-601: Is still a major form of aquaculture in Central and Eastern Europe , including the Russian Federation , where most of the production comes from low or intermediate-intensity ponds. In Asia , the farming of carp continues to surpass the total amount of farmed fish volume of intensively sea-farmed species, such as salmon and tuna . Selective breeding programs for the common carp include improvement in growth, shape, and resistance to disease. Experiments carried out in

1577-614: Is the Dead Sea . Drainage basins have been historically important for determining territorial boundaries, particularly in regions where trade by water has been important. For example, the English crown gave the Hudson's Bay Company a monopoly on the fur trade in the entire Hudson Bay basin, an area called Rupert's Land . Bioregional political organization today includes agreements of states (e.g., international treaties and, within

1660-454: Is the queen of rivers; a stately, a good, and a very subtle fish; that was not at first bred, nor hath been long in England , but is now naturalised." Carp are variable in terms of angling value. Various species of carp have been domesticated and reared as food fish across Europe and Asia for thousands of years. These various species appear to have been domesticated independently, as

1743-404: Is used only in its original sense, that of the drainage divide line. A drainage basin's boundaries are determined by watershed delineation , a common task in environmental engineering and science. In a closed drainage basin, or endorheic basin , rather than flowing to the ocean, water converges toward the interior of the basin, known as a sink , which may be a permanent lake, a dry lake , or

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1826-642: Is usually colored in gold or pink, shimmering with an unmistakably auspicious tone. The modern Japanese Koi fish are a brightly colored species of the Amur carp that have been bred by rice farmers in Japan since the early 19th century. This subspecies of carp plays a significant role in Japanese art, often being depicted as symbols of luck, strength, and tenacity. For this reason, Koi fish are also presented as gifts in Japanese culture as symbols of love, gratitude, and peace. Their bright colors and unique patterns present

1909-713: The African Great Lakes , the interiors of Australia and the Arabian Peninsula , and parts in Mexico and the Andes . Some of these, such as the Great Basin, are not single drainage basins but collections of separate, adjacent closed basins. In endorheic bodies of water where evaporation is the primary means of water loss, the water is typically more saline than the oceans. An extreme example of this

1992-828: The Continental Divide , northern Alaska and parts of North Dakota , South Dakota , Minnesota , and Montana in the United States, the north shore of the Scandinavian peninsula in Europe, central and northern Russia, and parts of Kazakhstan and Mongolia in Asia , which totals to about 17% of the world's land. Just over 13% of the land in the world drains to the Pacific Ocean . Its basin includes much of China, eastern and southeastern Russia, Japan,

2075-662: The Guide to the Proposed Murray–Darling Basin Plan , was released in October 2010 as the first part of a three-stage process to address the problems of the Murray–Darling Basin. The Plan was in response to the 2000s Australian drought , and designed to secure the long-term ecological health of the Murray–Darling Basin. This entailed cutting existing water allocations and tree growth environmental flows . The Basin Plan

2158-714: The Korean Peninsula , most of Indochina, Indonesia and Malaysia, the Philippines, all of the Pacific Islands , the northeast coast of Australia , and Canada and the United States west of the Continental Divide (including most of Alaska), as well as western Central America and South America west of the Andes. The Indian Ocean 's drainage basin also comprises about 13% of Earth's land. It drains

2241-680: The Old World , they are considered trash fish and invasive pests in many parts of Africa , Australia and most of the United States . The cypriniformes (family Cyprinidae) are traditionally grouped with the Characiformes , Siluriformes , and Gymnotiformes to create the superorder Ostariophysi , since these groups share some common features. These features include being found predominantly in fresh water and possessing Weberian ossicles , an anatomical structure derived from

2324-609: The Ramsar Convention of Wetlands of International Importance. The rivers listed below comprise the Murray–Darling Basin and its direct significant tributaries, with elevations of their confluence with the downstream river. The tributary with the highest elevation is Swampy Plain River that rises in the Snowy Mountains, below Mount Kosciuszko at an elevation of 2,120 metres (6,960 ft), and ends merging with

2407-562: The USSR used crossings of broodstocks to increase genetic diversity, and then selected the species for traits such as growth rate, exterior traits and viability, and/or adaptation to environmental conditions such as variations in temperature. Selected carp for fast growth and tolerance to cold, the Ropsha carp. The results showed a 30 to 77.4% improvement of cold tolerance, but did not provide any data for growth rate. An increase in growth rate

2490-686: The black , grass , silver and bighead carp . In the 1950s, the Pearl River Fishery Research Institute in China made a technological breakthrough in the induced breeding of these carps, which has resulted in a rapid expansion of freshwater aquaculture in China. In the late 1990s, scientists at the Chinese Academy of Fishery Sciences developed a new variant of the common carp called the Jian carp ( Cyprinus carpio var. Jian ). This fish grows rapidly and has

2573-554: The groundwater . A drainage basin is an area of land where all flowing surface water converges to a single point, such as a river mouth, or flows into another body of water, such as a lake or ocean. Carp The term carp ( pl. : carp) is a generic common name for numerous species of freshwater fish from the family Cyprinidae , a very large clade of ray-finned fish mostly native to Eurasia . While carp are prized quarries and are valued (even commercially cultivated ) as both food and ornamental fish in many parts of

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2656-533: The 1890s. Currently, 4 major reservoirs, 14 lock and weir structures, and five coastal barrages interject the water flowing down the Murray–Darling. Of the approximately 13,000 gigalitres (13,000 hm; 10,500,000 acre⋅ft) of flow in the Basin, which studies have shown to be divertible, 11,500 gigalitres (11,500 hm; 9,320,000 acre⋅ft) are removed for irrigation, industrial use, and domestic supply. Agricultural irrigation accounts for about 95 percent of

2739-739: The Australian landmass, is one of the country's most significant agricultural areas providing one-third of Australia's food supply. Located west of the Great Dividing Range , it drains southwest into the Great Australian Bight and spans most of the states of New South Wales and Victoria , the Australian Capital Territory , and parts of the states of Queensland (the lower third) and South Australia (the southeastern corner). The Basin

2822-476: The Basin, a very low biodiversity. Over Christmas 2018 and January 2019 there were two mass deaths of fish in the waters of the Basin, the first numbering 10,000, the second in the hundreds of thousands. Species affected were Murray cod , golden perch , silver perch and bony herring. Some blamed the draining of water from the Menindee Lakes by WaterNSW , with only 2.5% of the original water volume in

2905-473: The Basin, the Murray and Darling, bring water from the high ranges of the east and carry it west then south through long flat and dry inland areas, often resulting in alluvial channel wetlands, such as The (Great) Cumbung Swamp , at the terminus of the Lachlan and Murrumbidgee Rivers. Nevertheless, these waters are subject to major diversions for municipal drinking supplies and irrigated agriculture that began in

2988-458: The Basin. In most years only half of this quantity reaches the sea and in dry years much less. Estimated total annual flows for the Basin have ranged from 5,000 gigalitres (5,000 hm; 4,100,000 acre⋅ft) in 1902 to 57,000 gigalitres (57,000 hm; 46,000,000 acre⋅ft) in 1956. Despite the magnitude of the Basin, the hydrology of the streams within it is quite varied. These waters are divided into four types: The two principal rivers of

3071-689: The Commonwealth and State governments and numerous submissions from interested stakeholders and the community, the Basin Plan became law in November 2012 and can now be implemented. Drainage basin Other terms for a drainage basin are catchment area , catchment basin , drainage area , river basin , water basin , and impluvium . In North America, they are commonly called a watershed , though in other English-speaking places, "watershed"

3154-582: The Gillard Government and following a period of sustained criticism of the Authority and the implementation of the proposed draft Basin plan. He was replaced by former New South Wales Planning Minister, Craig Knowles . In late May 2012, the revised plan was forwarded to state water ministers. It did not alter the recommendation to cut 2,750 gigalitres (2.75 km; 2,230,000 acre⋅ft) of water entitlements. Following much negotiation between

3237-551: The Murray River, descending 1,860 metres (6,100 ft). The ordering of the Basin, from downstream to upstream, is: The Basin affects five states and territory governments, which according to the Constitution , are responsible for managing water resources. The River Murray Commission was established in 1917. Under the River Murray Waters Agreement , which did not include Queensland though about

3320-487: The Murray–Darling Basin, providing approximately 2,100 gigalitres (7.4×10 cu ft) of water a year to the Basin for use in Australia's irrigated agriculture industry, which is worth about A$ 3 billion per annum, representing more than 40% of the gross value of the nation's agricultural production. The Basin was once home to a large number of Aboriginal people whose traditional lifestyle and cultures were gradually altered by

3403-494: The Murray–Darling. These structures and irrigation implements were ideal when there was a steady flow of water. However, during "the Big Dry", as the early 2000s drought came to be known, Australian farmers experienced a scarcity unlike ever before. The drought was so severe that numerous rivers and streams such as the Murray–Darling stopped flowing. The Basin contains more than 30,000 wetlands . Eleven of these are protected under

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3486-528: The Ostariophysi have such a great capacity for hearing. Most cypriniformes have scales and teeth on the inferior pharyngeal bones which may be modified in relation to the diet. Tribolodon is the only cyprinid genus which tolerates salt water. Several species move into brackish water but return to fresh water to spawn. All of the other cypriniformes live in continental waters and have a wide geographical range. Some consider all cyprinid fishes carp , and

3569-623: The US, interstate compacts ) or other political entities in a particular drainage basin to manage the body or bodies of water into which it drains. Examples of such interstate compacts are the Great Lakes Commission and the Tahoe Regional Planning Agency . In hydrology , the drainage basin is a logical unit of focus for studying the movement of water within the hydrological cycle . The process of finding

3652-548: The United States, and, worldwide, large sums of money are spent on carp control. At least some species of carp are able to survive for months with practically no oxygen (for example under ice or in stagnant, scummy water) by metabolizing glycogen to form lactic acid which is then converted into ethanol and carbon dioxide . The ethanol diffuses into the surrounding water through the gills . In 1653 Izaak Walton wrote in The Compleat Angler , "The Carp

3735-606: The Victorian Farmers Federation and Wine Group Growers' Australia. Conversely, support for the Murray–Darling Basin plan has been received by various groups, including Australian Conservation Foundation , and Environment Victoria . New legal advice from Commonwealth government lawyers is changing the plan. The Government's interpretation is that the plan must give equal weight to the environmental, social, and economic impacts of proposed cuts to irrigation. Environmentalists and South Australian irrigators, at

3818-590: The arrival of Europeans, while others were outright killed by the settlers. Although some tribes organised resistance, such as the Maraura , whose territory lay around the Rufus River above Renmark and the Tanganekald near The Coorong , they were eventually either killed, exiled, or succumbed to disease. The Murray–Darling Basin is home to many native animal species. The true numbers may not be known, but

3901-406: The basin, it can form tributaries that change the structure of the land. There are three different main types, which are affected by the rocks and ground underneath. Rock that is quick to erode forms dendritic patterns, and these are seen most often. The two other types of patterns that form are trellis patterns and rectangular patterns. Rain gauge data is used to measure total precipitation over

3984-626: The cause to (naturally occurring) hypoxic blackwater . Initial investigations by the New South Wales Environment Protection Authority (EPA) included single water samples at six sites and were criticised as inadequate. Subsequently it was announced that the New South Wales government will treat the deaths as a "pollution incident", thus giving the EPA greater investigative powers; earlier testing

4067-430: The discharge of water from a basin may be made by a stream gauge located at the basin's outlet. Depending on the conditions of the drainage basin, as rainfall occurs some of it seeps directly into the ground. This water will either remain underground, slowly making its way downhill and eventually reaching the basin, or it will permeate deeper into the soil and consolidate into groundwater aquifers. As water flows through

4150-441: The drainage area is dependent on the soil type. Certain soil types such as sandy soils are very free-draining, and rainfall on sandy soil is likely to be absorbed by the ground. However, soils containing clay can be almost impermeable and therefore rainfall on clay soils will run off and contribute to flood volumes. After prolonged rainfall even free-draining soils can become saturated , meaning that any further rainfall will reach

4233-697: The drainage basin to the mouth, and may accumulate there, disturbing the natural mineral balance. This can cause eutrophication where plant growth is accelerated by the additional material. Because drainage basins are coherent entities in a hydrological sense, it has become common to manage water resources on the basis of individual basins. In the U.S. state of Minnesota , governmental entities that perform this function are called " watershed districts ". In New Zealand, they are called catchment boards. Comparable community groups based in Ontario, Canada, are called conservation authorities . In North America, this function

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4316-857: The eastern coast of Africa, the coasts of the Red Sea and the Persian Gulf , the Indian subcontinent , Burma, and most parts of Australia . The five largest river basins (by area), from largest to smallest, are those of the Amazon (7 million km ), the Congo (4 million km ), the Nile (3.4 million km ), the Mississippi (3.22 million km ), and the Río de la Plata (3.17 million km ). The three rivers that drain

4399-737: The end of the river in South Australia, say that the authority should stick to its original figure. In October 2010, a parliamentary inquiry into the economic impacts of the plan was announced. In late October 2010 the Water Minister, Tony Burke, played down the prospect of a High Court challenge to the Murray–Darling Basin plan, as confusion continued over new legal advice released by the Government. In response to community concerns that MDBA had put environmental issues first over social and economic needs, Burke released new advice on

4482-465: The family Cyprinidae itself is often known as the carp family. In colloquial use, carp usually refers only to several larger cyprinid species such as Cyprinus carpio (common carp), Carassius carassius (crucian carp), Ctenopharyngodon idella (grass carp), Hypophthalmichthys molitrix (silver carp), and Hypophthalmichthys nobilis (bighead carp). Common carp are native to both Eastern Europe and Western Asia , so they are sometimes called

4565-429: The first five anterior-most vertebrae, and their corresponding ribs and neural crests. The third anterior-most pair of ribs is in contact with the extension of the labyrinth and the posterior with the swim bladder. The function is poorly understood, but this structure is presumed to take part in the transmission of vibrations from the swim bladder to the labyrinth and in the perception of sound, which would explain why

4648-583: The greatest portion of western Sub-Saharan Africa , as well as Western Sahara and part of Morocco . The two major mediterranean seas of the world also flow to the Atlantic. The Caribbean Sea and Gulf of Mexico basin includes most of the U.S. interior between the Appalachian and Rocky Mountains , a small part of the Canadian provinces of Alberta and Saskatchewan , eastern Central America ,

4731-435: The ground and along rivers it can pick up nutrients , sediment , and pollutants . With the water, they are transported towards the outlet of the basin, and can affect the ecological processes along the way as well as in the receiving water body . Modern use of artificial fertilizers , containing nitrogen (as nitrates ), phosphorus , and potassium , has affected the mouths of drainage basins. The minerals are carried by

4814-422: The ground at its terminus, the area can go by several names, such playa, salt flat, dry lake , or alkali sink . The largest endorheic basins are in Central Asia , including the Caspian Sea , the Aral Sea , and numerous smaller lakes. Other endorheic regions include the Great Basin in the United States, much of the Sahara Desert , the drainage basin of the Okavango River ( Kalahari Basin ), highlands near

4897-417: The islands of the Caribbean and the Gulf, and a small part of northern South America. The Mediterranean Sea basin, with the Black Sea , includes much of North Africa , east-central Africa (through the Nile River ), Southern , Central, and Eastern Europe , Turkey , and the coastal areas of Israel , Lebanon , and Syria . The Arctic Ocean drains most of Western Canada and Northern Canada east of

4980-424: The lakes being left; after the first fish kill, both the Department of Primary Industries (DPI) and WaterNSW blamed the ongoing drought affecting Australia, while the DPI blamed the second kill on a disruption of an algal bloom caused by a sudden fall in temperature. In March 2023, millions of fish were reported dead along the Darling River at Menindee, following a heatwave. As the cleanup began, police attributed

5063-452: The late Han period includes an anecdote which relates how a man far away from home sent back to his wife a pair of carp ( Chinese : 鲤鱼 ; pinyin : Liyu ), in which, when the wife opened the fish to cook, she found a silk strip that carried a love note of just two lines: "Eat well to keep fit, missing you and forget me not". At the Yellow River at Henan ( Chinese : 河南 ; pinyin : Hénán ; Wade–Giles : Ho-nan )

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5146-409: The most water, from most to least, are the Amazon, Ganges , and Congo rivers. Endorheic basin are inland basins that do not drain to an ocean. Endorheic basins cover around 18% of the Earth's land. Some endorheic basins drain to an Endorheic lake or Inland sea . Many of these lakes are ephemeral or vary dramatically in size depending on climate and inflow. If water evaporates or infiltrates into

5229-467: The national perspective was needed for effective management. The Murray–Darling Basin Agreement was first adopted in 1985 but it wasn't until 1993 that its full legal status was enacted. The Agreement led to the creation of a number of new organisations under what is known as the Murray–Darling Basin Initiative. These included the Murray–Darling Basin Ministerial Council and the Murray–Darling Basin Commission . The Murray–Darling Basin Authority (MDBA)

5312-473: The plan's environmental outcomes. With the release of the Guide to the Proposed Murray–Darling Basin Plan there have been a number of protests and voiced concerns about the plan in rural towns that the MDBA visited to present the plan to consultation meetings. More than 5,000 people attended a MDBA meeting in Griffith where Griffith Mayor, Mike Neville, said the plan would "obliterate" Murrumbidgee valley communities. Other groups also echo this feeling, such as

5395-404: The public meeting that more work is being done to look at how the proposed cuts would affect regional communities. He stated: "Importantly, we want to make sure the social and economic impacts—which under any sort of scenario is very significant—were fully teased out". Taylor resigned as he allegedly believed that the overriding principle should be the environmental outcome which was in conflict with

5478-418: The rainfall on the area of land included in its polygon. These polygons are made by drawing lines between gauges, then making perpendicular bisectors of those lines form the polygons. The isohyetal method involves contours of equal precipitation are drawn over the gauges on a map. Calculating the area between these curves and adding up the volume of water is time-consuming. Isochrone maps can be used to show

5561-477: The requirements of the Water Act . Burke stated that the Act does allow for the authority to "optimise" the needs of all three areas, but constitutional lawyer, George Williams, had cast doubts over the interpretation of the laws, stating it could be subject to a legal challenge. The MDBA announced in November 2010 that it might be forced to push back the release of its final plan for the river system until early 2012. The then MDBA chairman, Mike Taylor , reassured

5644-572: The responsibility of the countries sharing it. Nile Basin Initiative , OMVS for Senegal River , Mekong River Commission are a few examples of arrangements involving management of shared river basins. Management of shared drainage basins is also seen as a way to build lasting peaceful relationships among countries. The catchment is the most significant factor determining the amount or likelihood of flooding . Catchment factors are: topography , shape, size, soil type, and land use (paved or roofed areas). Catchment topography and shape determine

5727-461: The river rather than being absorbed by the ground. If the surface is impermeable the precipitation will create surface run-off which will lead to higher risk of flooding; if the ground is permeable, the precipitation will infiltrate the soil. Land use can contribute to the volume of water reaching the river, in a similar way to clay soils. For example, rainfall on roofs, pavements , and roads will be collected by rivers with almost no absorption into

5810-413: The royal or a noble family, perhaps through marriage, but in particular through success in the imperial examination . It is therefore an idiom often used to encourage students or children to achieve success through hard work and perseverance. This symbolic image, as well as the image of the carp itself, has been one of the most popular themes in Chinese paintings, especially those of popular styles. The fish

5893-418: The speed with which the runoff reaches a river. A long thin catchment will take longer to drain than a circular catchment. Size will help determine the amount of water reaching the river, as the larger the catchment the greater the potential for flooding. It is also determined on the basis of length and width of the drainage basin. Soil type will help determine how much water reaches the river. The runoff from

5976-452: The system. Cane toads compete with native amphibians and are toxic to native carnivores. Phyla canescens has invaded wetlands and floodplains with heavy clay soils in the Murray–Darling Basin, to the detriment of the native vegetation; the plant does best in habitats that are inundated occasionally, although it cannot compete with the grass Paspalum distichum and the sedge Eleocharis plana in more heavily inundated sites. This area

6059-415: The time taken for rain to reach the river, while catchment size, soil type, and development determine the amount of water to reach the river. Generally, topography plays a big part in how fast runoff will reach a river. Rain that falls in steep mountainous areas will reach the primary river in the drainage basin faster than flat or lightly sloping areas (e.g., > 1% gradient). Shape will contribute to

6142-477: The time taken for runoff water within a drainage basin to reach a lake, reservoir or outlet, assuming constant and uniform effective rainfall. Drainage basins are the principal hydrologic unit considered in fluvial geomorphology . A drainage basin is the source for water and sediment that moves from higher elevation through the river system to lower elevations as they reshape the channel forms. Drainage basins are important in ecology . As water flows over

6225-791: The various domesticated carp species are native to different parts of Eurasia . Aquaculture has been pursued in China for at least 2,400 years. A tract by Fan Li in the fifth century BC details many of the ways carp were raised in ponds . The common carp ( Cyprinus carpio ) is originally from Central Europe . Several carp species (collectively known as Asian carp ) were domesticated in East Asia . Carp that are originally from South Asia , for example catla ( Gibelion catla ), rohu ( Labeo rohita ) and mrigal ( Cirrhinus cirrhosus ), are known as Indian carp . Their hardiness and adaptability have allowed domesticated species to be propagated all around

6308-421: The water removed, including for the growing of rice and cotton . This extraction is highly controversial among scientists in Australia, regarding the agriculture industry's high water use in a region extremely short of water (as much due to exceptionally low run-off coefficients as to low rainfall). These extensive irrigation systems require a reliable supply of water, not the unpredictable flows that characterise

6391-673: The world's land drains to the Atlantic Ocean . In North America , surface water drains to the Atlantic via the Saint Lawrence River and Great Lakes basins, the Eastern Seaboard of the United States, the Canadian Maritimes , and most of Newfoundland and Labrador . Nearly all of South America east of the Andes also drains to the Atlantic, as does most of Western and Central Europe and

6474-464: The world. Although the carp was an important aquatic food item, as more fish species have become readily available for the table, the importance of carp culture in Western Europe has diminished. Demand has declined, partly due to the appearance of more desirable table fish such as trout and salmon through intensive farming , and environmental constraints. However, fish production in ponds

6557-493: Was described as being primarily intended to ensure public safety. Four varieties of carp were used to stock up fish dams. Since then they have made their way into the river systems, where they spread quite quickly. Human introduction, possibly by anglers using small carp illegally as live bait, has also increased their distribution. These fish are very mobile, breed rapidly and can survive in very shallow water and through long periods of very low dissolved oxygen content. Carp are

6640-443: Was designed to set environmentally sustainable limits on the quantities of water that may be taken from Basin water resources , to set Basin-wide environmental, water quality and salinity objectives, to develop efficient water trading regimes across the Basin, to set requirements for state water resource plans and to improve water security for all Basin users. It also intends to minimise social and economic impacts whilst achieving

6723-625: Was formed in 2008 to manage the Murray–Darling Basin in an integrated and sustainable manner. The MDBA is responsible for preparing and overseeing a legally-enforceable management plan. In October 2010, MDBA released a draft Murray–Darling Basin Plan (MDBP) for consultation. On 22nd November 2012, Tony Burke signed the Murray–Darling Basin Plan, which passed the Australian Parliament's disallowance period on 19 March 2013. The MDBA's draft Murray–Darling Basin Plan, titled

6806-469: Was observed in the second generation in Vietnam , Moav and Wohlfarth (1976) showed positive results when selecting for slower growth for three generations compared to selecting for faster growth. Schaperclaus (1962) showed resistance to the dropsy disease wherein selected lines suffered low mortality (11.5%) compared to unselected (57%). The major carp species used traditionally in Chinese aquaculture are

6889-466: Was said to have been created after the flood by the god-emperor Yu, who split a mountain blocking the path of the Yellow River. It was so famous that throughout China was a common saying, "a student facing his examinations is like a carp attempting to leap the Dragon Gate." Henan is not the only place where this happens. Many other waterfalls in China also have the name Dragon Gate and much the same

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