|
Goby Lake
Goby Lake is a marine lake located on Koror island in Palau. There are about 70 other marine lakes located throughout the Rock Islands and Koror. Goby Lake is notable for endemic subspecies of golden jellyfish and is one of five marine lakes in Palau used for several scientific researches in evolutionary biology the other lakes being Jellyfish Lake, Clear Lake (Palau), Uet era Ngermeuangel, Uet era Ongael. Golden jellyfish Clear Lake is connected to the ocean through fissures and tunnels in the limestone of ancient Miocene reef. However the lake is sufficiently isolated and the conditions are different enough that the diversity of species in the lake is greatly reduced from the nearby lagoon. The golden jellyfish ''Mastigias'' cf. ''papua nakamurai'' and possibly other species in the lake have evolved to be substantially different from their close relatives living in the nearby lagoons. The lake is rich with several species of fish, including goby, giving to lake its name. Lak ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Koror
Koror is the state comprising the main commercial centre of the Republic of Palau. It consists of several islands, the most prominent being Koror Island (also ''Oreor Island''). It is Palau’s most populous state. History In the oral tradition of Palau, Koror is one of the children of Milad, and thus occupies an important position in traditional belief. In addition, Koror is the home of the clan of the Ibedul, the high chief of Palau. Several traditional villages in Koror span the volcanic and rock island portions. Many of the stone platforms , odesongel, serve as clan cemeteries, and other stone features serve as shrines. The lagoon is an important resource area, and was probably intensively exploited prehistorically. The first sighting of Koror, Babeldaob, and Peleliu recorded by Westerners was by the Spanish expedition of Ruy López de Villalobos at the end of January, 1543. They were then charted as ''Los Arrecifes'' (The Reefs in Spanish). In November and December 1710 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miocene
The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recent" because it has 18% fewer modern marine invertebrates than the Pliocene has. The Miocene is preceded by the Oligocene and is followed by the Pliocene. As Earth went from the Oligocene through the Miocene and into the Pliocene, the climate slowly cooled towards a series of ice ages. The Miocene boundaries are not marked by a single distinct global event but consist rather of regionally defined boundaries between the warmer Oligocene and the cooler Pliocene Epoch. During the Early Miocene, the Arabian Peninsula collided with Eurasia, severing the connection between the Mediterranean and Indian Ocean, and allowing a faunal interchange to occur between Eurasia and Africa, including the dispersal of proboscideans into Eurasia. During the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lakes Of Palau
A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much larger oceans, they do form part of the Earth's water cycle. Lakes are distinct from lagoons, which are generally coastal parts of the ocean. Lakes are typically larger and deeper than ponds, which also lie on land, though there are no official or scientific definitions. Lakes can be contrasted with rivers or streams, which usually flow in a channel on land. Most lakes are fed and drained by rivers and streams. Natural lakes are generally found in mountainous areas, rift zones, and areas with ongoing glaciation. Other lakes are found in endorheic basins or along the courses of mature rivers, where a river channel has widened into a basin. Some parts of the world have many lakes formed by the chaotic drainage patterns left over from the last ice ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meromictic
A meromictic lake is a lake which has layers of water that do not intermix. In ordinary, holomictic lakes, at least once each year, there is a physical mixing of the surface and the deep waters. The term ''meromictic'' was coined by the Austrian Ingo Findenegg in 1935, apparently based on the older word ''holomictic''. The concepts and terminology used in describing meromictic lakes were essentially complete following some additions by G. Evelyn Hutchinson in 1937. Characteristics Most lakes are ''holomictic''; that is, at least once per year, physical mixing occurs between the surface and the deep waters. In so-called monomictic lakes, the mixing occurs once per year; in dimictic lakes, the mixing occurs twice a year (typically spring and autumn), and in polymictic lakes, the mixing occurs several times a year. In meromictic lakes, however, the layers of the lake water can remain unmixed for years, decades, or centuries. Meromictic lakes can usually be divided into th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemocline
A chemocline is a type of cline, a layer of fluid with different properties, characterized by a strong, vertical chemistry gradient within a body of water. In bodies of water where chemoclines occur, the cline separates the upper and lower layers, resulting in different properties for those layers. The lower layer shows a change in the concentration of dissolved gases and solids compared to the upper layer. Chemoclines most commonly occur where local conditions favor the formation of anoxic bottom water — deep water deficient in oxygen, where only anaerobic forms of life can exist. Common anaerobic organisms that live in these conditions include phototrophic purple sulfur bacteria and green sulfur bacteria. The Black Sea is an example of a body of water with a prominent chemocline, though similar bodies (classified as meromictic lakes) exist across the globe. Meromictic lakes are the result of meromixis, which is a circumstance where a body of water does not fully mix and cir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypoxia (environmental)
Hypoxia refers to low oxygen conditions. Normally, 20.9% of the gas in the atmosphere is oxygen. The partial pressure of oxygen in the atmosphere is 20.9% of the total barometric pressure. In water, oxygen levels are much lower, approximately 7 ppm or 0.0007% in good quality water, and fluctuate locally depending on the presence of photosynthetic organisms and relative distance to the surface (if there is more oxygen in the air, it will diffuse across the partial pressure gradient). Atmospheric hypoxia Atmospheric hypoxia occurs naturally at high altitudes. Total atmospheric pressure decreases as altitude increases, causing a lower partial pressure of oxygen, which is defined as hypobaric hypoxia. Oxygen remains at 20.9% of the total gas mixture, differing from hypoxic hypoxia, where the percentage of oxygen in the air (or blood) is decreased. This is common in the sealed burrows of some subterranean animals, such as blesmols. Atmospheric hypoxia is also the basis of altitude tra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water Oxygenation
Water aeration is the process of increasing or maintaining the oxygen saturation of water in both natural and artificial environments. Aeration techniques are commonly used in pond, lake, and reservoir management to address low oxygen levels or algal blooms. Water quality Water aeration is often required in water bodies that suffer from hypoxic or anoxic conditions, often caused by upstream human activities such as sewage discharges, agricultural run-off, or over-baiting a fishing lake. Aeration can be achieved through the infusion of air into the bottom of the lake, lagoon or pond or by surface agitation from a fountain or spray-like device to allow for oxygen exchange at the surface and the release of gasses such as carbon dioxide, methane or hydrogen sulfide. Decreased levels of dissolved oxygen (DO) is a major contributor to poor water quality. Not only do fish and most other aquatic animals need oxygen, aerobic bacteria help decompose organic matter. When oxygen concentrati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake Stratification
Lake stratification is the tendency of lakes to form separate and distinct thermal layers during warm weather. Typically stratified lakes show three distinct layers, the Epilimnion comprising the top warm layer, the thermocline (or Metalimnion): the middle layer, which may change depth throughout the day, and the colder Hypolimnion extending to the floor of the lake. Definition The thermal stratification of lakes refers to a change in the temperature at different depths in the lake, and is due to the density of water varying with temperature. Cold water is denser than warm water and the epilimnion generally consists of water that is not as dense as the water in the hypolimnion. However, the temperature of maximum density for freshwater is 4 °C. In Temperate climate, temperate regions where lake water warms up and cools through the seasons, a cyclical pattern of overturn occurs that is repeated from year to year as the cold dense water at the top of the lake sinks (see stab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uet Era Ongael
Uet era Ongael (Ongael Lake) is a marine lake located on Ongael Island, Koror, in Palau. There are about 70 other marine lakes located throughout the Rock Islands and Koror. Uet era Ongael is notable for endemic subspecies of golden jellyfish and is one of five marine lakes in Palau used for several scientific researches in evolutionary biology, the other lakes being Jellyfish Lake, Clear Lake, Uet era Ngermeuangel and Goby Lake. Golden jellyfish Uet era Ongael is connected to the ocean through fissures and tunnels in the limestone of ancient Miocene reefs. However the lake is sufficiently isolated and the conditions are different enough that the diversity of species in the lake is greatly reduced from the nearby lagoon. The golden jellyfish ''Mastigias'' cf. '' papua remengesaui'' is substantially different from their close relatives living in the nearby lagoons. This is the most ornate of Palau lake jellyfishes, with solid white spots; younger jellyfish have a pale blue c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palau
Palau,, officially the Republic of Palau and historically ''Belau'', ''Palaos'' or ''Pelew'', is an island country and microstate in the western Pacific. The nation has approximately 340 islands and connects the western chain of the Caroline Islands with parts of the Federated States of Micronesia. It has a total area of . The most populous island is Koror, home to the country's most populous city of the same name. The capital Ngerulmud is located on the nearby island of Babeldaob, in Melekeok State. Palau shares maritime boundaries with international waters to the north, the Federated States of Micronesia to the east, Indonesia to the south, and the Philippines to the northwest. The country was originally settled approximately 3,000 years ago by migrants from Maritime Southeast Asia. Palau was first drawn on a European map by the Czech missionary Paul Klein based on a description given by a group of Palauans shipwrecked on the Philippine coast on Samar. Palau islands ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uet Era Ngermeuangel
Uet era Ngermeuangel (Ngermeuangel Lake, Big Jellyfish Lake) is a marine lake located on Koror island in Palau. There are about 70 other marine lakes located throughout the Rock Islands and Koror. Uet era Ngermeuangel is notable for endemic subspecies of golden jellyfish and is one of five marine lakes in Palau used for several scientific researches in evolutionary biology the other lakes being Jellyfish Lake, Clear Lake (Palau), Goby Lake, Uet era Ongael. Golden jellyfish Uet era Ngermeuangel is connected to the ocean through fissures and tunnels in the limestone of ancient Miocene reef. However the lake is sufficiently isolated and the conditions are different enough that the diversity of species in the lake is greatly reduced from the nearby lagoon. The golden jellyfish ''Mastigias'' cf. ''papua remeliiki'' and possibly other species in the lake have evolved to be substantially different from their close relatives living in the nearby lagoons. In the lake there is living als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clear Lake (Palau)
Clear Lake (also Clearwater Lake) is a marine lake located on Eil Malk island in Palau. Eil Malk (also Mecherchar) is part of the Rock Islands, a group of small, rocky, mostly uninhabited islands in Palau's Southern Lagoon, between Koror and Peleliu. There are about 70 other marine lakes located throughout the Rock Islands. Clear Lake is notable for endemic subspecies of golden jellyfish and is one of five marine lakes in Palau used for several scientific researches in evolutionary biology, the other lakes being Jellyfish Lake, Goby Lake, Uet era Ngermeuangel, Uet era Ongael. Golden jellyfish Clear Lake is one of the oldest of Meromictic_lake, meromictic marine lakes in Palau and is circa 15,000 - 12,000 years old. It is connected to the ocean through fissures and tunnels in the limestone of ancient Miocene reef. However the lake is sufficiently isolated and the conditions are different enough that the diversity of species in the lake is greatly reduced from the nearby lagoon. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.svg "Click for more on -> Lake Stratification")