"of complete drainage systems. Closed water flow areas often lead to the concentration of salts and other minerals in the basin. Minerals leached from the surrounding rocks are deposited in the basin, and left behind when the water evaporates. Thus endorheic basins often contain extensive salt pans (also called salt flats, salt lakes, alkali flats, dry lake beds or playas). These areas tend to be large, flat hardened surfaces and are sometimes used for aviation runways or land speed record attempts, because of their extensive areas of perfectly level terrain. Both permanent and seasonal endorheic lakes can form in endorheic"
"Open and closed lakes Open and closed lakes refer to the major subdivisions of lakes - bodies of water surrounded by land. Exorheic, or open lakes drain into a river, or other body of water that ultimately drains into the ocean. Endorheic basins fall into the category of endorheic or closed lakes, wherein waters do not drain into the ocean, but are reduced by evaporation, and/or drain into the ground. An open lake is a lake where water constantly flows out under almost all climatic circumstances. Because water does not remain in an open lake for any length of time,"
"leave the lake. The drainage from an open lake, like that from ordinary rivers, is referred to as exorheic (from the Greek ""exos"", outside and ""rhein"", to flow). In a closed lake (see endorheic drainage), no water flows out, and water which is not evaporated will remain in a closed lake indefinitely. This means that closed lakes are usually saline, though this salinity varies greatly from around three parts per thousand for most of the Caspian Sea to as much as 400 parts per thousand for the Dead Sea. Only the less salty closed lakes are able to sustain life,"
"lake. Open and closed lakes Open and closed lakes refer to the major subdivisions of lakes - bodies of water surrounded by land. Exorheic, or open lakes drain into a river, or other body of water that ultimately drains into the ocean. Endorheic basins fall into the category of endorheic or closed lakes, wherein waters do not drain into the ocean, but are reduced by evaporation, and/or drain into the ground. An open lake is a lake where water constantly flows out under almost all climatic circumstances. Because water does not remain in an open lake for any length of"
"Endorheic basin An endorheic basin (also endoreic basin or endorreic basin) (from the , ""éndon"", ""within"" and , ""rheîn"", ""to flow"") is a limited drainage basin that normally retains water and allows no outflow to other external bodies of water, such as rivers or oceans, but converges instead into lakes or swamps, permanent or seasonal, that equilibrate through evaporation. Such a basin may also be referred to as a closed or terminal basin or as an internal drainage system or interior drainage basin. Endorheic regions, in contrast to exorheic regions which flow to the ocean in geologically defined patterns, are"
"an outflow channel to the Malheur River that is normally dry, but flows in years of peak precipitation. Examples of relatively humid regions in endorheic basins often exist at high elevation. These regions tend to be marshy and are subject to substantial flooding in wet years. The area containing Mexico City is one such case, with annual precipitation of 850 mm and characterized by waterlogged soils that require draining. Endorheic regions tend to be far inland with their boundaries defined by mountains or other geological features that block their access to oceans. Since the inflowing water can evacuate only through"
"readily explained by the concentration of salts and other evaporite minerals by the evaporation of water from stream-fed lakes lacking external outlets, called ""endorheic lakes"", in arid climates. The composition of the salts and other evaporate minerals found in these lakes is consistent with their precipitation from dissolved material continually carried into the lakes by rivers and streams and subsequent concentration by evaporation instead of evaporation of sea water. Whether a lake becomes salty or not simply depends on whether the lake lacks an outlet and the relative balance between water flowing into the lake and leaving the lake via"
"closed hydrologic systems. Their surface waters drain to inland terminal locations where the water evaporates or seeps into the ground, having no access to discharge into the sea. Endorheic water bodies include some of the largest lakes in the world, such as the Caspian Sea, the world's largest saline inland sea. Endorheic basins constitute local base levels, defining a limit of erosion and deposition processes of nearby areas. Endorheic lakes are bodies of water that do not flow into the sea. Most of the water falling on Earth finds its way to the oceans through a network of rivers, lakes"
"and wetlands. However, there is a class of water bodies that are located in closed or endorheic watersheds where the topography prevents their drainage to the oceans. These endorheic watersheds (containing water in rivers or lakes that form a balance of surface inflows, evaporation and seepage) are often called terminal lakes or sink lakes. Endorheic lakes are usually in the interior of a landmass, far from an ocean in areas of relatively low rainfall. Their watersheds are often confined by natural geologic land formations such as a mountain range, cutting off water egress to the ocean. The inland water flows"
"stream, which maintain a lake's average level by allowing the drainage of excess water. Some lakes do not have a natural outflow and lose water solely by evaporation or underground seepage or both. They are termed endorheic lakes. Many lakes are artificial and are constructed for hydro-electric power generation, aesthetic purposes, recreational purposes, industrial use, agricultural use or domestic water supply. Evidence of extraterrestrial lakes exists; ""definitive evidence of lakes filled with methane"" was announced by NASA as returned by the Cassini Probe observing the moon Titan, which orbited the planet Saturn. Globally, lakes are greatly outnumbered by ponds: of"
"are: Large endorheic regions in Africa are located in the Sahara Desert, the Kalahari Desert, and the East African Rift: Many small lakes and ponds in North Dakota and the Northern Great Plains are endorheic; some of them have salt encrustations along their shores. Though a large portion of Europe drains to the endorheic Caspian Sea, Europe's wet climate means it contains relatively few terminal lakes itself: any such basin is likely to continue to fill until it reaches an overflow level connecting it with an outlet or erodes the barrier blocking its exit. Exceptions include: All these lakes are"
"basins. Some endorheic basins are essentially stable, climate change having reduced precipitation to the degree that a lake no longer forms. Even most permanent endorheic lakes change size and shape dramatically over time, often becoming much smaller or breaking into several smaller parts during the dry season. As humans have expanded into previously uninhabitable desert areas, the river systems that feed many endorheic lakes have been altered by the construction of dams and aqueducts. As a result, many endorheic lakes in developed or developing countries have contracted dramatically, resulting in increased salinity, higher concentrations of pollutants, and the disruption of"
"land drains to endorheic lakes or seas or sinks. The largest of these consists of much of the interior of Asia, which drains into 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 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."
"ecosystems. Even within exorheic basins, there can be ""non-contributing"", low-lying areas that trap runoff and prevent it from contributing to flows downstream during years of average or below-average runoff. In flat river basins, non-contributing areas can be a large fraction of the river basin, e.g. Lake Winnipeg's basin. A lake may be endorheic during dry years and can overflow its basin during wet years, e.g., the former Tulare Lake. Because the Earth's climate has recently been through a warming and drying phase with the end of the Ice Ages, many endorheic areas such as Death Valley that are now dry"
"sea level. A peninsula projecting from the south shore and an island off the north shore divide the lake into two basins: a smaller, relatively shallow eastern one, between deep, and a larger western one, deep. It is endorheic (lacking a drainage outlet) and the water is brackish. There is a small village with the same name on the eastern shore of the lake. Although the lake lies within a national park, much of the surroundings are used as pasture. The lake, with its islands, marshes, wet meadows, peat bogs, and pebbly and sandy plains, has been identified by BirdLife"
"higher, riparian erosion will generally carve drainage channels (particularly in times of flood), or cause the water level in the terminal lake to rise until it finds an outlet, breaking the enclosed endorheic hydrological system's geographical barrier and opening it to the surrounding terrain. The Black Sea was likely such a lake, having once been an independent hydrological system before the Mediterranean Sea broke through the terrain separating the two. Lake Bonneville was another such lake, overflowing its basin in the Bonneville flood. The Malheur/Harney lake system in Oregon is normally cut off from drainage to the ocean, but has"
"depth"", a measure of transparency. The Secchi disk is commonly used to test for eutrophication. For a detailed look at these processes, see lentic ecosystems. A lake moderates the surrounding region's temperature and climate because water has a very high specific heat capacity (4,186 J·kg·K). In the daytime a lake can cool the land beside it with local winds, resulting in a sea breeze; in the night it can warm it with a land breeze. The lake may be infilled with deposited sediment and gradually become a wetland such as a swamp or marsh. Large water plants, typically reeds, accelerate"
"with ongoing glaciation. Other lakes are found in endorheic basins or along the courses of mature rivers. In some parts of the world there are many lakes because of chaotic drainage patterns left over from the last Ice Age. All lakes are temporary over geologic time scales, as they will slowly fill in with sediments or spill out of the basin containing them. Many lakes are artificial and are constructed for industrial or agricultural use, for hydro-electric power generation or domestic water supply, or for aesthetic or recreational purposes or even for other activities. The word ""lake"" comes from Middle"
"Lake capture In geology, lake capture is the process of capture (see Stream capture) of the waters collected in a lake by a neighbor river basin. The occurrence of a lake capture is mainly controlled by the water balance at the lake's basin and the changes in topography due to erosion, sedimentation, and tectonism. If evaporation at the surface of a lake, plus the water losses through underground infiltration and plant evapotranspiration are high enough to account for all precipitation water collected by the lake, then the lake becomes endorheic, closed, or internally drained. This situation prevails until the water"
"seepage or evaporation, dried minerals or other products collect in the basin, eventually making the water saline and also making the basin vulnerable to pollution. Continents vary in their concentration of endorheic regions due to conditions of geography and climate. Australia has the highest percentage of endorheic regions at 21 percent while North America has the least at 5 percent. Approximately 18 percent of the earth's land drains to endorheic lakes or seas, the largest of these land areas being the interior of Asia. In deserts, water inflow is low and loss to solar evaporation high, drastically reducing the formation"
"deserts were large lakes relatively recently. During the last ice age, the Sahara may have contained lakes larger than any now existing. Endorheic lakes in Antarctica are located in the McMurdo Dry Valleys, Victoria Land, the largest ice-free area in Antarctica. Much of western and Central Asia is a giant endorheic region made up of a number of contiguous closed basins. The region contains several basins and terminal lakes, including: Other endorheic lakes and basins in Asia include: Australia, being very dry and having exceedingly low runoff ratios due to its ancient soils, has many endorheic drainages. The most important"
"particular concern is the potential eutrophication of currently oligotrophic Lake Ohrid from increased pollution. Indeed, sediment cores show a ~3.5 fold increase in phosphorus concentration over the past century. On the one hand, shifts from endemic to common European species, which are better adapted to higher nutrient conditions, have already been observed close to polluted inflows. On the other hand, higher nutrient levels have reduced the water transparency, as well as the oxygen availability in the deep water and at the lake bottom, two properties which are requisite for the endemic flora and fauna. Still, the lake is in a"
"water, which in turn can be used to derive the biomass. This relationship is expressed in the following equation: A lake is usually classified as being in one of three possible classes: ""oligotrophic"", ""mesotrophic"" or ""eutrophic"". Lakes with extreme trophic indices may also be considered ""hyperoligotrophic"" or ""hypereutrophic"". The table below demonstrates how the index values translate into trophic classes. Oligotrophic lakes generally host very little or no aquatic vegetation and are relatively clear, while eutrophic lakes tend to host large quantities of organisms, including algal blooms. Each trophic class supports different types of fish and other organisms, as well."
"East African Rift Valley. The pH of most freshwater lakes is on the alkaline side of neutrality and many exhibit similar water chemistries to soda lakes, only less extreme. In order for a lake to become alkalic, a special combination of geographic, geological and climatic conditions are required. First of all, a suitable topography is needed, that limits the outflow of water from the lake. When the outflow is completely prevented, this is called an endorheic basin. Craters or depressions formed by tectonic rifting often provide such topological depressions. The high alkalinity and salinity arise through evaporation of the lake"
"lake. During interglacial periods, the climate becomes arid once more and causes the lakes to evaporate and dry up. Pluvial lake A pluvial lake is a body of water that accumulated in a basin because of a greater moisture availability resulting from changes in temperature and/or precipitation. These intervals of greater moisture availability are not always contemporaneous with glacial periods. Pluvial lakes are typically closed lakes that occupied endorheic basins. Pluvial lakes that have since evaporated and dried out may also be referred to as ""paleolakes"". The word comes from the Latin ""pluvia"", which means ""rain"". Pluvial lakes represent changes"
"balance changes again and the lake overburdens the limits of its basin or until the lake capture occurs. Opening the drainage of an endorheic lacustrine basin by fluvial erosion generally implies a lake capture. Lake captures are therefore very sensitive to the preexisting topography as well as to climatic and lithological factors. A climatic change towards more humid conditions can result in a higher water level in the internally drained basin, eventually causing overflow, this . In a longer time-scale, sediment colmatation of the lacustrine basin can also lead to overflow. Both can hinder the relative importance of the capture"
"processed by bacteria, which have a symbiotic relationship with seep mussels living at the edge of the pool. This ecosystem is dependent on chemical energy, and relative to almost all other life on Earth, has little dependence on energy from the Sun. Inland endorheic basins are drainage basins without an outlet to the sea. Often, they have salt lakes or salt seas, which can evaporate. This can lead to problems with dust, which can be toxic as salt seas often absorb heavy metals and minerals including selenium, which can be poisonous if allowed to accumulate. Environmental change over time can"
"Lake Tanganyika. The Malagarasi is older than Lake Tanganyika and, before the lake was formed, directly drained into the Congo River. The lake has a complex history of changing flow patterns, due to its high altitude, great depth, slow rate of refill and mountainous location in a turbulently volcanic area that has undergone climate changes. Apparently it has rarely in the past had an outflow to the sea. It has been described as 'practically endorheic' for this reason. The lake's connection to the sea is dependent on a high water level allowing water to overflow out of the lake through"
"no outlet at present and the water is brackish though not very perceptible to taste. The lake is fed by springs and snow-melt from the adjacent mountains. Most water enters the lake in two major stream systems, one entering the lake from the north, the other from the southwest. Both stream systems include extensive marshes where they enter the lake. It formerly had an outlet to the south, but this has become blocked and the lake has become a endorheic lake. The lake is oligotrophic in nature, and its waters are alkaline. Accessibility to the lake is largely limited to"
"some debate over the definition of the trophic status of Lake Ellesmere / Te Waihora. Although the lake has high nutrient and phytoplankton values that place it in the category of hypertrophic (extremely enriched) the lake does not exhibit many of the characteristics of such a classification. For example, it does not regularly undergo severe oxygen depletion, nor does it produce unsightly toxic algal blooms or fish kills, unlike other lakes in the area with the same trophic status. Furthermore, it supports abundant fish and bird communities. Recently it has been recognised that the combination of abstraction and climate was"
"implying that the apparent early developmental processes in lakes were dominated by colonization effects, and lags due to the limited reproductive potential of the colonising organisms. In a classic paper, Raymond Lindeman outlined a hypothetical developmental sequence, with lakes progressively developing through oligotrophic, mesotrophic, and eutrophic stages, before senescing to a dystrophic stage and filling completely with sediment. A climax forest community would eventually be established on the peaty fill of the former lake basin. These ideas were further elaborated by Ed Deevey, who suggested that lake development was dominated by a process of morphometric eutrophication. As the hypolimnion of"
"climate conditions and human water requirements vary, these will create fluctuations in the lake level. Lakes can be also categorized on the basis of their richness in nutrients, which typically affect plant growth. Nutrient-poor lakes are said to be ""oligotrophic"" and are generally clear, having a low concentration of plant life. ""Mesotrophic lakes"" have good clarity and an average level of nutrients. ""Eutrophic"" lakes are enriched with nutrients, resulting in good plant growth and possible algal blooms. ""Hypertrophic"" lakes are bodies of water that have been excessively enriched with nutrients. These lakes typically have poor clarity and are subject to"
"of eutrophication can occur naturally and by human impact on the environment. Eutrophic comes from the Greek ""eutrophos"" meaning ""well-nourished"", from ""eu"" meaning good and ""trephein"" meaning ""to nourish"" Hypereutrophic lakes are very nutrient-rich lakes characterized by frequent and severe nuisance algal blooms and low transparency. Hypereutrophic lakes have a visibility depth of less than 3 feet, they have greater than 40 micrograms/litre total chlorophyll and greater than 100 micrograms/litre phosphorus. The excessive algal blooms can also significantly reduce oxygen levels and prevent life from functioning at lower depths creating dead zones beneath the surface. Likewise, large algal blooms can"