A log boom (sometimes called a log fence or log bag) is a barrier placed in a river, designed to collect and or contain floating logs timbered from nearby forests. The term is also used as a place where logs were collected into booms, as at the mouth of a river. With several firms driving on the same stream, it was necessary to direct the logs to their owner's respective booms, with each log identified by its own patented timber mark. One of the most well known logbooms was in Williamsport, Pennsylvania, along the Susquehanna River. The development and completion of that specific log boom in 1851 made Williamsport the "Lumber Capital of the World".
As the logs proceeded downstream, they encountered these booms in a manner that allowed log drivers to control their progress, eventually guiding them to the river mouth or sawmills. Most importantly, the booms could be towed across lakes, like rafts, or anchored while individual logs awaited their turn to go through the mill. Booms prevented the escape into open waters of these valuable assets.
Log boom foundations were commonly constructed of piles or large stones placed into cribs in a river to form small islands. The booms were themselves large floating logs linked together end to end, like a large floating chain connecting the foundations while strategically guiding the transported logs along their path.
Large blocks of ice commonly threaten booms, pushing free-flowing logs over the structures. Significantly large chunks of ice can even gain enough power so as to break through the boom altogether, freeing the logs and endangering unsuspecting people and wildlife located downstream. Moreover, flooding and the changing of the seasons fluctuate water levels, occasionally causing jams that can extend for miles on end.
Log booms were used in the United States and British North America throughout the 19th and early 20th centuries. During the largely bloodless Aroostook War that centred on the disputed border between Maine and New Brunswick, hastily built booms proved pricy for local governments. The 1,300-foot-long Aroostook Boom, made of confiscated timber and containing seven piers, cost the state of Maine more than $15,000 to construct. Licensed loggers commonly sent their wood in easily manageable raft units, but illegal lumbermen cunningly sent loose timber, complicating the sorting process and angering officials. Booms often caused friction between the disputing governments; when political tensions intensified, loggers and soldiers targeted enemy booms with arms and explosives. (Full article...)
Ecoforestry has been defined as selection forestry or restoration forestry. The main idea of ecoforestry is to maintain or restore the forest to standards where the forest may still be harvested for products on a sustainable basis. Ecoforestry is forestry that emphasizes holistic practices which strive to protect and restore ecosystems rather than maximize economic productivity. Sustainability of the forest also comes with uncertainties. There are other factors that may affect the forest furthermore than that of the harvesting. There are internal conditions such as effects of soil compaction, tree damage, disease, fire, and blow down that also directly affect the ecosystem. These factors have to be taken into account when determining the sustainability of a forest. If these factors are added to the harvesting and production that comes out of the forest, then the forest will become less likely to survive, and will then become less sustainable.
Since the forest is considered an ecosystem, it is dependent on all of the living and non-living factors within itself. This is a major part of why the forest needs to be sustainable before it is harvested. For example, a tree, by way of photosynthesis, converts sunlight to sugars for respiration to keep the tree alive. The remains of the converted sugars is left in roots for consumption by the organisms surrounding the tree in the habitat. This shows the productivity of an ecosystem with its inhabitants. Productivity within the ecosystem cannot come to fruition unless the forest is sustainable enough to be harvested. If most individual organisms of the ecosystem vanish, the ecosystem itself is at risk. Once that happens, there is no longer any forest to harvest from. The overall productivity of a system can be found in an equation where the Net Primary Production, or NPP, is equal to the Gross Primary Production, or GPP, minus the Respiration, or R. The formula is the NPP = GPP - R. The NPP is the overall efficiency of the plants in the ecosystem. Through having a constant efficiency in NPP, the ecosystem is then more sustainable. The GPP refers to the rate of energy stored by photosynthesis in plants. The R refers to the maintenance and reproduction of plants from the energy expended.
Ecoforestry has many principles within the existence of itself. It covers sustainable development and the fair harvesting of the organisms living within the forest ecosystem. There have been many proposals of principles outlined for ecoforestry. They are covered over books, articles, and environmental agencies. All of the principles relate to the idea that in ecoforestry, less should be harvested, and diversity must be managed. Through harvesting less, there is enough biomass left in the forest, so that the forest may stay healthy and still stay maintained. It will grow at a sustainable level annually, and thus it will be able to still be harvested the following year. Through management of the diversity, species may cohabitate in an ecosystem where the forest may feed off of other species in its growth and production. The Principles of Ecoforestry may be found below. (Full article...)
A timber slide is a device for moving timber past rapids and waterfalls. Their use in Canada was widespread in the 18th and 19th century timber trade. At this time, cut timber would be floated down rivers in large timber rafts from logging camps to ports such as Montreal and Saint John, New Brunswick. Rapids and waterfalls would, however, damage the wood and could potentially cause log jams. Thus at these locations timber slides were constructed. These were thin water filled chutes that would run parallel to the river. They would usually only be wide enough for a single log and one at a time the logs would be directed down it. The idea is attributed to Ruggles Wright who introduced the first one in 1829 not far from what is today down-town Hull, Quebec, Canada. Later, the slides could often be up to a kilometre in length. They were most commonly found on the Ottawa River system. The Bonnechere River in Eastern Ontario had five chutes along the waterway before emptying into the Ottawa River.
In some areas the timber slide became a tourist attraction, the most notable being the 1.2 km chute bypassing the Chaudière Falls on the Ottawa River in Ottawa. Its most notable visitors are the Duke of York, who later became King George V, and his wife, the Duchess of YorkMary of Teck.
Timber slides disappeared after the construction of canal networks and the decline of the timber trade. They were almost all out of service by the First World War. (Full article...)
Environmental history first emerged in the United States out of the environmental movement of the 1960s and 1970s, and much of its impetus still stems from present-day global environmental concerns. The field was founded on conservation issues but has broadened in scope to include more general social and scientific history and may deal with cities, population or sustainable development. As all history occurs in the natural world, environmental history tends to focus on particular time-scales, geographic regions, or key themes. It is also a strongly multidisciplinary subject that draws widely on both the humanities and natural science.
The subject matter of environmental history can be divided into three main components. The first, nature itself and its change over time, includes the physical impact of humans on the Earth's land, water, atmosphere and biosphere. The second category, how humans use nature, includes the environmental consequences of increasing population, more effective technology and changing patterns of production and consumption. Other key themes are the transition from nomadic hunter-gatherer communities to settled agriculture in the Neolithic Revolution, the effects of colonial expansion and settlements, and the environmental and human consequences of the Industrial and technological revolutions. Finally, environmental historians study how people think about nature – the way attitudes, beliefs and values influence interaction with nature, especially in the form of myths, religion and science. (Full article...)
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The International Analog Forestry Network (IAFN) is a non-governmental organization (NGO) that seeks to conserve and restore biodiversity worldwide through the application of analog forestry. The IAFN links a variety of community, governmental, and private organizations (29 as of November, 2012), as well as a number of individuals, who apply the practices and principles of analog forestry in their work.
The IAFN was established in 1995 to facilitate the exchange of knowledge and experience among analog forestry practitioners and to further promote the system. The IAFN supports its partners through the development of technical manuals and promotional materials, training, research, and creating improved marketing opportunities. The IAFN established and currently monitors the Forest Garden Product standard, a certification standard for goods produced within forest gardens, which encompasses the requirements of most organic certification but with additional restrictions to further the protection of biodiversity. FGP standards are being adapted to certify minerals that have been "responsibly mined," as well as ecosystem services and products, such as carbon credits.
The Scheduled Tribes and Other Traditional Forest Dwellers (Recognition of Forest Rights) Act, 2006, is a key piece of forest legislation passed in India on 18 December 2006. It has also been called the Forest Rights Act, the Tribal Rights Act, the Tribal Bill, and the Tribal Land Act. The law concerns the rights of forest-dwelling communities to land and other resources, denied to them over decades as a result of the continuance of colonial forest laws in India.
Supporters of the Act claim that it will redress the "historical injustice" committed against forest dwellers, while including provisions for making conservation more effective and more transparent. The demand for the law has seen massive national demonstrations involving hundreds of thousands of people.
However, the law has also been the subject of considerable controversy in India. Opponents of the law claim it will lead to massive forest destruction and should be repealed.
A little over one year after it was passed, the Act was notified into force on 31 December 2007. On 1 January 2008, this was followed by the notification of the Rules framed by the Ministry of Tribal Affairs to supplement the procedural aspects of the Act. (Full article...)
Biologic carbon sequestration is a naturally occurring process as part of the carbon cycle. Humans can enhance it through deliberate actions and use of technology. Carbon dioxide (CO 2) is naturally captured from the atmosphere through biological, chemical, and physical processes. These processes can be accelerated for example through changes in land use and agricultural practices, called carbon farming. Artificial processes have also been devised to produce similar effects. This approach is called carbon capture and storage. It involves using technology to capture and sequester (store) CO 2 that is produced from human activities underground or under the sea bed.
Plants, such as forests and kelp beds, absorb carbon dioxide from the air as they grow, and bind it into biomass. However, these biological stores may be temporary carbon sinks, as long-term sequestration cannot be guaranteed. Wildfires, disease, economic pressures, and changing political priorities may release the sequestered carbon back into the atmosphere.
Carbon dioxide that has been removed from the atmosphere can also be stored in the Earth's crust by injecting it underground, or in the form of insolublecarbonate salts. The latter process is called mineral sequestration. These methods are considered non-volatile because they not only remove carbon dioxide from the atmosphere but also sequester it indefinitely. This means the carbon is "locked away" for thousands to millions of years.
To enhance carbon sequestration processes in oceans the following chemical or physical technologies have been proposed: ocean fertilization, artificial upwelling, basalt storage, mineralization and deep-sea sediments, and adding bases to neutralize acids. However, none have achieved large scale application so far. Large-scale seaweed farming on the other hand is a biological process and could sequester significant amounts of carbon. The potential growth of seaweed for carbon farming would see the harvested seaweed transported to the deep ocean for long-term burial. The IPCC Special Report on the Ocean and Cryosphere in a Changing Climate recommends "further research attention" on seaweed farming as a mitigation tactic. (Full article...)
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A tree plantation, forest plantation, plantation forest, timber plantation or tree farm is a forest planted for high volume production of wood, usually by planting one type of tree as a monoculture forest. The term tree farm also is used to refer to tree nurseries and Christmas tree farms. Plantation forestry can produce a high volume of wood in a short period of time. Plantations are grown by state forestry authorities (for example, the Forestry Commission in Britain) and/or the paper and wood industries and other private landowners (such as Weyerhaeuser, Rayonier and Sierra Pacific Industries in the United States or Asia Pulp & Paper in Indonesia). Christmas trees are often grown on plantations, and in southern and southeastern Asia, teak plantations have recently replaced the natural forest.Industrial plantations are actively managed for the commercial production of forest products. Industrial plantations are usually large-scale. Individual blocks are usually even-aged and often consist of just one or two species. These species can be exotic or indigenous. The plants used for the plantation are often genetically altered for desired traits such as growth and resistance to pests and diseases in general and specific traits, for example in the case of timber species, volumic wood production and stem straightness. Forest genetic resources are the basis for genetic alteration. Selected individuals grown in seed orchards are a good source for seeds to develop adequate planting material.
Wood production on a tree plantation is generally higher than that of natural forests. While forests managed for wood production commonly yield between 1 and 3 cubic meters per hectare per year, plantations of fast-growing species commonly yield between 20 and 30 cubic meters or more per hectare annually; a Grand Fir plantation in Scotland has a growth rate of 34 cubic meters per hectare per year, and Monterey Pine plantations in southern Australia can yield up to 40 cubic meters per hectare per year. In 2000, while plantations accounted for 5% of global forest, it is estimated that they supplied about 35% of the world's roundwood.
The highest share of plantation forest is in South America, where this forest type represents 99 percent of the total planted-forest area and 2 percent of the total forest area. The lowest share of plantation forest is in Europe, where it represents 6 percent of the planted forest estate and 0.4 percent of the total forest area. Globally, 44 percent of plantation forests are composed mainly of introduced species. There are large differences between regions: for example, plantation forests in North and Central America mostly comprise native species and those in South America consist almost entirely of introduced species. (Full article...)
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The Scheduled Tribes and Other Traditional Forest Dwellers (Recognition of Forest Rights) Act, 2006, is a key piece of forest legislation passed in India on 18 December 2006. It has also been called the Forest Rights Act, the Tribal Rights Act, the Tribal Bill, and the Tribal Land Act. The law concerns the rights of forest-dwelling communities to land and other resources, denied to them over decades as a result of the continuance of colonial forest laws in India.
Supporters of the Act claim that it will redress the "historical injustice" committed against forest dwellers, while including provisions for making conservation more effective and more transparent. The demand for the law has seen massive national demonstrations involving hundreds of thousands of people.
However, the law has also been the subject of considerable controversy in India. Opponents of the law claim it will lead to massive forest destruction and should be repealed.
A little over one year after it was passed, the Act was notified into force on 31 December 2007. On 1 January 2008, this was followed by the notification of the Rules framed by the Ministry of Tribal Affairs to supplement the procedural aspects of the Act. (Full article...)
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Ecoforestry has been defined as selection forestry or restoration forestry. The main idea of ecoforestry is to maintain or restore the forest to standards where the forest may still be harvested for products on a sustainable basis. Ecoforestry is forestry that emphasizes holistic practices which strive to protect and restore ecosystems rather than maximize economic productivity. Sustainability of the forest also comes with uncertainties. There are other factors that may affect the forest furthermore than that of the harvesting. There are internal conditions such as effects of soil compaction, tree damage, disease, fire, and blow down that also directly affect the ecosystem. These factors have to be taken into account when determining the sustainability of a forest. If these factors are added to the harvesting and production that comes out of the forest, then the forest will become less likely to survive, and will then become less sustainable.
Since the forest is considered an ecosystem, it is dependent on all of the living and non-living factors within itself. This is a major part of why the forest needs to be sustainable before it is harvested. For example, a tree, by way of photosynthesis, converts sunlight to sugars for respiration to keep the tree alive. The remains of the converted sugars is left in roots for consumption by the organisms surrounding the tree in the habitat. This shows the productivity of an ecosystem with its inhabitants. Productivity within the ecosystem cannot come to fruition unless the forest is sustainable enough to be harvested. If most individual organisms of the ecosystem vanish, the ecosystem itself is at risk. Once that happens, there is no longer any forest to harvest from. The overall productivity of a system can be found in an equation where the Net Primary Production, or NPP, is equal to the Gross Primary Production, or GPP, minus the Respiration, or R. The formula is the NPP = GPP - R. The NPP is the overall efficiency of the plants in the ecosystem. Through having a constant efficiency in NPP, the ecosystem is then more sustainable. The GPP refers to the rate of energy stored by photosynthesis in plants. The R refers to the maintenance and reproduction of plants from the energy expended.
Ecoforestry has many principles within the existence of itself. It covers sustainable development and the fair harvesting of the organisms living within the forest ecosystem. There have been many proposals of principles outlined for ecoforestry. They are covered over books, articles, and environmental agencies. All of the principles relate to the idea that in ecoforestry, less should be harvested, and diversity must be managed. Through harvesting less, there is enough biomass left in the forest, so that the forest may stay healthy and still stay maintained. It will grow at a sustainable level annually, and thus it will be able to still be harvested the following year. Through management of the diversity, species may cohabitate in an ecosystem where the forest may feed off of other species in its growth and production. The Principles of Ecoforestry may be found below. (Full article...)
Heli-logging, or helicopter logging, is a method of logging that uses helicopters to remove cut trees from forests by lifting them on cables attached to a helicopter. Helicopter logging is often used in inaccessible areas of forests. Because the use of helicopters reduces the level of infrastructure required to log in a specific location, the method also helps to reduce the environmental impact of logging. It also can increase the productivity in these remote areas. (Full article...)
Many tools like remote sensing, GIS and photogrammetry modelling have been developed to improve forest inventory and management planning. Scientific research plays a crucial role in helping forest management. For example, climate modeling, biodiversity research, carbon sequestration research, GIS applications, and long-term monitoring help assess and improve forest management, ensuring its effectiveness and success. (Full article...)
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Turpentine (which is also called spirit of turpentine, oil of turpentine, terebenthine, terebenthene, terebinthine and, colloquially, turps) is a fluid obtained by the distillation of resin harvested from living trees, mainly pines. Principally used as a specialized solvent, it is also a source of material for organic syntheses.
Pinus ponderosa, commonly known as the ponderosa pine, bull pine, blackjack pine, western yellow-pine, or filipinus pine, is a very large pine tree species of variable habitat native to mountainous regions of western North America. It is the most widely distributed pine species in North America.
Pinus ponderosa grows in various erect forms from British Columbia southward and eastward through 16 western U.S. states and has been introduced in temperate regions of Europe and in New Zealand. It was first documented in modern science in 1826 in eastern Washington near present-day Spokane (of which it is the official city tree). On that occasion, David Douglas misidentified it as Pinus resinosa (red pine). In 1829, Douglas concluded that he had a new pine among his specimens and coined the name Pinus ponderosa for its heavy wood. In 1836, it was formally named and described by Charles Lawson, a Scottish nurseryman. It was adopted as the official state tree of Montana in 1949. (Full article...)
Mycoforestry is an ecological forest management system implemented to enhance forest ecosystems and plant communities, by introducing the mycorrhizal and saprotrophicfungi. Mycoforestry is considered a type of permaculture and can be implemented as a beneficial component of an agroforestry system. It can enhance the yields of tree crops and produce edible mushrooms, an economically valuable product. By integrating plant-fungal associations into a forestry management system, native forests can be preserved, wood waste can be recycled back into the ecosystem, carbon sequestration can be increased, planted restoration sites are enhanced, and the sustainability of forest ecosystems are improved. Mycoforestry is an alternative to the practice of clearcutting, which removes dead wood from forests, thereby diminishing nutrient availability and reducing soil depth. (Full article...)
The cables can be rigged in several configurations.
There are two classes;
High lead logging, in which a simple loop of cable runs from the yarder out through pulley blocks anchored to stumps at the far end of the cut.
Skyline, in which a carriage, pulled by hauling cables, runs along a skyline cable, providing vertical lift to the logs.
There are other varieties of loading systems as well.
While skyline logging requires additional setup, the vertical lift of the skyline allows faster yarding, which can outweigh the additional labor costs, especially on larger harvest units.
Since the 1980s grapple yarders have become popular.
Skyline and grapple yarding, however, require more complex, and expensive equipment. A traditional high lead or gravity system will function with just two cables, a skidding line. As the names imply the skidding line is used to drag the logs in, and the haulback line is used to drag the skidding line back out for the next turn (or group of logs).
A skyline system will add a third line---the skyline whose function is to hold the skidding line and the haulback line off the ground or 'in the sky'.
The yarder itself is located on a landing, a flat area on top of the ridge that is being logged. After the trees are retrieved by the yarder, the limbs are bucked (removed) and the logs are then placed in piles awaiting transport. (Full article...)
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Ecoforestry has been defined as selection forestry or restoration forestry. The main idea of ecoforestry is to maintain or restore the forest to standards where the forest may still be harvested for products on a sustainable basis. Ecoforestry is forestry that emphasizes holistic practices which strive to protect and restore ecosystems rather than maximize economic productivity. Sustainability of the forest also comes with uncertainties. There are other factors that may affect the forest furthermore than that of the harvesting. There are internal conditions such as effects of soil compaction, tree damage, disease, fire, and blow down that also directly affect the ecosystem. These factors have to be taken into account when determining the sustainability of a forest. If these factors are added to the harvesting and production that comes out of the forest, then the forest will become less likely to survive, and will then become less sustainable.
Since the forest is considered an ecosystem, it is dependent on all of the living and non-living factors within itself. This is a major part of why the forest needs to be sustainable before it is harvested. For example, a tree, by way of photosynthesis, converts sunlight to sugars for respiration to keep the tree alive. The remains of the converted sugars is left in roots for consumption by the organisms surrounding the tree in the habitat. This shows the productivity of an ecosystem with its inhabitants. Productivity within the ecosystem cannot come to fruition unless the forest is sustainable enough to be harvested. If most individual organisms of the ecosystem vanish, the ecosystem itself is at risk. Once that happens, there is no longer any forest to harvest from. The overall productivity of a system can be found in an equation where the Net Primary Production, or NPP, is equal to the Gross Primary Production, or GPP, minus the Respiration, or R. The formula is the NPP = GPP - R. The NPP is the overall efficiency of the plants in the ecosystem. Through having a constant efficiency in NPP, the ecosystem is then more sustainable. The GPP refers to the rate of energy stored by photosynthesis in plants. The R refers to the maintenance and reproduction of plants from the energy expended.
Ecoforestry has many principles within the existence of itself. It covers sustainable development and the fair harvesting of the organisms living within the forest ecosystem. There have been many proposals of principles outlined for ecoforestry. They are covered over books, articles, and environmental agencies. All of the principles relate to the idea that in ecoforestry, less should be harvested, and diversity must be managed. Through harvesting less, there is enough biomass left in the forest, so that the forest may stay healthy and still stay maintained. It will grow at a sustainable level annually, and thus it will be able to still be harvested the following year. Through management of the diversity, species may cohabitate in an ecosystem where the forest may feed off of other species in its growth and production. The Principles of Ecoforestry may be found below. (Full article...)
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Bernhard Eduard Fernow (/ˈfɜːrnaʊ/FUR-now; January 7, 1851 – February 6, 1923) was the third chief of the U.S. Department of Agriculture's Division of Forestry of the United States from 1886 to 1898, preceding Gifford Pinchot in that position, and laying much of the groundwork for the establishment of the United States Forest Service in 1905. Fernow's philosophy toward forest management may be traced to Heinrich Cotta's preface to Anweisung zum Waldbau (Instruction in Silviculture) or Linnaeus' ideas on the "economy of nature." Fernow has been called the "father of professional forestry in the United States." (Full article...)
While a biome can cover small areas, a microbiome is a mix of organisms that coexist in a defined space on a much smaller scale. For example, the human microbiome is the collection of bacteria, viruses, and other microorganisms that are present on or in a human body.
A biota is the total collection of organisms of a geographic region or a time period, from local geographic scales and instantaneous temporal scales all the way up to whole-planet and whole-timescale spatiotemporal scales. The biotas of the Earth make up the biosphere. (Full article...)
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The Canadian Forest Service (CFS; French: Service canadien des forêts) is a sector of the Canadian government department of Natural Resources Canada. Part of the federal government since 1899, the CFS is a science-based policy organization responsible for promoting the sustainable development of Canada's forests and competitiveness of the forest sector to benefit present and future Canadians. Some of the research areas that the CFS is involved in include; forest fire, climate change, silviculture, soils, insects and disease, remote sensing and forest management. Since 1991 the sector has produced an annual report, The State of the Forest in Canada[1], which describes the status of the nation's forests and the forest industry. (Full article...)
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Taiga Rescue Network (TRN) was an international network of more than 200 non-governmental organizations, indigenous peoples and individuals working to defend the world's boreal forests, also known as Taiga. TRN was established in 1992 to give a voice to support, link and publicize local struggles fighting for the boreal forests and its peoples. TRN no longer exists. In 2010, TRN held its last conference in Sweden. The website remained online until April 2013. (Full article...)
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REDD+ (or REDD-plus) is a framework to encourage developing countries to reduce emissions and enhance removals of greenhouse gases through a variety of forest management options, and to provide technical and financial support for these efforts. The acronym refers to "reducing emissions from deforestation and forest degradation in developing countries, and the role of conservation, sustainable management of forests, and enhancement of forest carbon stocks in developing countries". REDD+ is a voluntary climate change mitigation framework developed by the United Nations Framework Convention on Climate Change (UNFCCC). REDD originally referred to "reducing emissions from deforestation in developing countries", which was the title of the original document on REDD. It was superseded by REDD+ in the Warsaw Framework on REDD-plus negotiations.Since 2000, various studies estimate that land use change, including deforestation and forest degradation, accounts for 12–29% of global greenhouse gas emissions. For this reason the inclusion of reducing emissions from land use change is considered essential to achieve the objectives of the UNFCCC. (Full article...)
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A log flume or lumber flume is a watertight flume constructed to transport lumber and logs down mountainous terrain using flowing water. Flumes replaced horse- or oxen-drawn carriages on dangerous mountain trails in the late 19th century. Logging operations preferred flumes whenever a reliable source of water was available. Flumes were cheaper to build and operate than logging railroads. They could span long distances across chasms with more lightweight trestles.
The relascope, invented by Walter Bitterlich, is a multi-use instrument for forest inventory. It is primarily used to find the height of a tree, the basal area of a tree, and the diameter of a tree anywhere along the bole. This instrument is used mostly for applications involving variable radius sample plots in a forest survey. (Full article...)
The board foot or board-foot is a unit of measurement for the volume of lumber in the United States and Canada. It equals the volume of a board that is one foot (30.5 cm) in length, one foot (30.5 cm) in width, and one inch (2.54 cm) in thickness, or exactly 2.359737216liters. Board foot can be abbreviated as FBM (for "foot, board measure"), BDFT, or BF. A thousand board feet can be abbreviated as MFBM, MBFT, or MBF. Similarly, a million board feet can be abbreviated as MMFBM, MMBFT, or MMBF.
Until the 1970s, in Australia and New Zealand, the terms super foot and superficial foot were used with the same meaning. (Full article...)
A cord is the amount of wood that, when "racked and well stowed" (arranged so pieces are aligned, parallel, touching, and compact), occupies a volume of 128 cubic feet (3.62 m3). This corresponds to a well-stacked woodpile 4 feet (122 cm) high, 8 feet (244 cm) wide, and 4 feet (122 cm) deep; or any other arrangement of linear measurements that yields the same volume.
The name cord probably comes from the use of a cord or string to measure it.
The face cord is a unit of volume for stacked firewood, 8 feet long, 4 feet wide, and 16 inches high—equal to 1/3 of a cord. The symbol for the unit is fc - cd. (Full article...)
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Ecoforestry has been defined as selection forestry or restoration forestry. The main idea of ecoforestry is to maintain or restore the forest to standards where the forest may still be harvested for products on a sustainable basis. Ecoforestry is forestry that emphasizes holistic practices which strive to protect and restore ecosystems rather than maximize economic productivity. Sustainability of the forest also comes with uncertainties. There are other factors that may affect the forest furthermore than that of the harvesting. There are internal conditions such as effects of soil compaction, tree damage, disease, fire, and blow down that also directly affect the ecosystem. These factors have to be taken into account when determining the sustainability of a forest. If these factors are added to the harvesting and production that comes out of the forest, then the forest will become less likely to survive, and will then become less sustainable.
Since the forest is considered an ecosystem, it is dependent on all of the living and non-living factors within itself. This is a major part of why the forest needs to be sustainable before it is harvested. For example, a tree, by way of photosynthesis, converts sunlight to sugars for respiration to keep the tree alive. The remains of the converted sugars is left in roots for consumption by the organisms surrounding the tree in the habitat. This shows the productivity of an ecosystem with its inhabitants. Productivity within the ecosystem cannot come to fruition unless the forest is sustainable enough to be harvested. If most individual organisms of the ecosystem vanish, the ecosystem itself is at risk. Once that happens, there is no longer any forest to harvest from. The overall productivity of a system can be found in an equation where the Net Primary Production, or NPP, is equal to the Gross Primary Production, or GPP, minus the Respiration, or R. The formula is the NPP = GPP - R. The NPP is the overall efficiency of the plants in the ecosystem. Through having a constant efficiency in NPP, the ecosystem is then more sustainable. The GPP refers to the rate of energy stored by photosynthesis in plants. The R refers to the maintenance and reproduction of plants from the energy expended.
Ecoforestry has many principles within the existence of itself. It covers sustainable development and the fair harvesting of the organisms living within the forest ecosystem. There have been many proposals of principles outlined for ecoforestry. They are covered over books, articles, and environmental agencies. All of the principles relate to the idea that in ecoforestry, less should be harvested, and diversity must be managed. Through harvesting less, there is enough biomass left in the forest, so that the forest may stay healthy and still stay maintained. It will grow at a sustainable level annually, and thus it will be able to still be harvested the following year. Through management of the diversity, species may cohabitate in an ecosystem where the forest may feed off of other species in its growth and production. The Principles of Ecoforestry may be found below. (Full article...)
Sparsely populated and landlocked, the Central African Republic is overwhelmingly agrarian. The vast bulk of the population engages in subsistence farming and 55% of the country's GDP derives from agriculture. Subsistence agriculture, together with forestry, remains the backbone of the economy of the Central African Republic (CAR), with more than 70% of the population living in outlying areas.
Aerial seeding is considered a broadcast method of seeding. It is often used to spread different grasses and legumes to large areas of land that are in need of vegetative cover after fires. Large wildfires can destroy large areas of plant life resulting in erosion hazards. Aerial seeding may quickly and effectively reduce erosion hazards and suppress growth of invasive plant species. Aerial seeding is an alternative to other seeding methods where terrain is extremely rocky or at high elevations or otherwise inaccessible. Problems with direct broadcast include germination, pests and seed predation by rodents or other wild animals. Transplanting seedlings from a plant nursery to the field is a more effective sowing technique. Aerial seeding has a low yield and require 25% to 50% more seeds than drilled seeding to achieve the same results.
Aerial seeding is also often used to plant cover crops. Some plants often seeded by this method are perennial rye (Timothy, Red Fescue, Red Top, Bluegrass), Sudan grass, soy beans, buckwheat, hairy vetch, corn, cereal rye, winter wheat, oats, mammoth or medium red clover, sweet clover, berseem clover and crimson clover (Timothy). (Full article...)
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The climate and ecology of different locations on the globe naturally separate into life zones, depending on elevation, location, and latitude. The generally strong dependency on elevation is known as altitudinal zonation: the average temperature of a location decreases as the elevation increases.
The general effect of elevation depends on atmospheric physics. However, the specific climate and ecology of any particular location depends on specific features of that location. This article provides a list of life zones by region, in order to illustrate the features of life zones for regions around the globe. (Full article...)
The southern African frilled shark (Chlamydoselachus africana) is a species of shark in the familyChlamydoselachidae, described in 2009. It is found in the deep waters off southern Angola to southern Namibia. This species is difficult to distinguish from the better-known frilled shark (C. anguineus), but is smaller at maturity and differs in several proportional measurements including head length and mouth width. It seems to be a specialized predator of smaller sharks, using its flexible jaws and numerous needle-like, recurved teeth to capture and swallow them whole. Reproduction is presumably aplacental viviparous, as with the other member of its family. (Full article...)
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Parmaturus is a genus of deepwater catsharks in the familyPentanchidae. Four species were described in 2007 and another in 2019 with more species likely to be described in the near future. (Full article...)
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The pale spotted catshark (Asymbolus pallidus) is a species of shark belonging to the familyPentanchidae, the deepwater catsharks. this shark is found only off Queensland, at depths of between 225 and 400 m (738 and 1,312 ft). Its length is up to 44 cm (17 in). (Full article...)
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The quagga catshark (Halaelurus quagga) is a species of shark belonging to the familyPentanchidae, the deepwater catsharks. A small, slim-bodied shark reaching 37 cm (15 in) in length, it has a distinctive color pattern of narrow, dark brown vertical bars, which resemble those of the quagga. Its head is short and flattened, with a pointed snout tip that is not upturned.
Little is known of the quagga catshark's natural history, as it is known only from nine specimens caught off southwestern India and eastern Somalia. Inhabiting the offshore waters of continental shelf at depths of 59–220 m (194–722 ft) or more, it is a bottom-dwellingpredator of shrimps. It exhibits an oviparous mode of reproduction, with a record of a female containing eight eggs that were enclosed in brown capsules bearing long tendrils at the corners. The International Union for Conservation of Nature (IUCN) presently lacks sufficient data to assess the conservation status of this species. It is not economically valued but is taken as bycatch. (Full article...)
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The necklace carpetshark (Parascyllium variolatum), also known as the varied carpetshark, is a carpetshark of the familyParascylliidaeendemic to the waters off Australia's southern coast between latitudes37°S and 41°S. It is found near the ocean floor over sand, rock, coral reefs, and kelp and seagrass beds at depths down to 180 m (590 ft). It is almost exclusively seen at night and spends the day hidden in caves or camouflaged on the ocean floor.
With a slender, elongated body and a maximum length of only 91.0 cm TL, it is harmless to humans. The tail is long, but difficult to tell apart from the rest of the shark. Its body is grey to brown in color with a broad black collar, from which it gets its name, and white spots along its body. It has small spiracles and nostrils with short barbels, likely used for sensory purposes. It is often mistaken for a species of catshark, despite being more closely related to wobbegongs and nurse sharks.
It is a nocturnalpredator and feeds mostly on shellfish. Reproduction is oviparous with females laying eggs with curled tendrils that anchor them to the ocean floor. The embryos feed on yolk. (Full article...)
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The dark shyshark or pretty happy (Haploblepharus pictus) is a species of shark belonging to the familyPentanchidae, the deepwater catsharks. This species is endemic to the temperate waters off southern Namibia and western South Africa. It is benthic in nature and inhabits shallow, inshore waters and favors rocky reefs and kelp forests. Growing to 60 cm (24 in) long, this small, stocky shark has a wide, flattened head with a rounded snout and a large flap of skin extending from before the nostrils to the mouth. Its dorsal coloration is extremely variable and may feature black-edged orange to blackish saddles and/or white spots on a light brown to nearly black background.
The cobbler wobbegong (Sutorectus tentaculatus) is a carpet shark in the familyOrectolobidae, the only member of the genusSutorectus. It is found in the subtropical eastern Indian Ocean around Western Australia between latitudes 26° S and 35° S. It is frequently found in rocky and coral reef areas. Cobbler wobbegongs reach a length of 92 cm. It has unbranched dermal lobes on the head, rows of warty tubercles along the back and black spots on the body and fins. (Full article...)
Paragaleus tengi is distinctive for its color and size. Specifically, its solid grey dorsal (upper) color, short snout, and 2-3 rows of lower teeth are a few of the characteristic traits that aid in distinguishing between this species of shark and others, like the Paragaleus pectoralis (White & Harris, 2013).
The tiger shark (Galeocerdo cuvier) is a species of ground shark, and the only extant member of the genus Galeocerdo and family Galeocerdonidae. It is a large macropredator, with females capable of attaining a length of over 5 m (16 ft 5 in). Populations are found in many tropical and temperate waters, especially around central Pacific islands. Its name derives from the dark stripes down its body, which resemble a tiger's pattern, but fade as the shark matures.
The tiger shark is a solitary, mostly nocturnal hunter. It is notable for having the widest food spectrum of all sharks, with a range of prey that includes crustaceans, fish, seals, birds, squid, turtles, sea snakes, dolphins, and others, even smaller sharks. It also has a reputation as a "garbage eater", consuming a variety of inedible, man-made objects that linger in its stomach. Tiger sharks have only one recorded natural predator, the orca. It is considered a near threatened species because of finning and fishing by humans.
The tiger shark is second only to the great white in recorded fatal attacks on humans, but these events are still exceedingly rare. (Full article...)
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The sand devil or Atlantic angel shark (Squatina dumeril) is a species of angelshark, family Squatinidae, native to the northwestern Atlantic Ocean. It occurs off the eastern United States, in the northern Gulf of Mexico, and possibly in parts of the Caribbean Sea. This bottom-dwelling shark is found in shallow inshore waters in summer and fall, and deep offshore waters in winter and spring. The sand devil's flattened body and enlarged pectoral and pelvic fins give it a ray-like appearance. There is a band of enlarged thorns running along the middle of its back. It is gray or brown in color, with scattered small dark spots. This species reaches 1.2–1.5 m (3.9–4.9 ft) in length.
The diet of the sand devil consists mainly of small teleost fishes and squid, which are captured via ambush attack. This species is viviparous, with the unborn young nourished by their yolk sacs. Females have a multi-year reproductive cycle and give birth to 4–25 pups in spring or early summer, following a 12-month gestation period. The sand devil is not aggressive, but may attempt to bite if harassed or captured. Though not valued economically, it is caught incidentally by commercialbottom trawlfisheries. (Full article...)
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The Australian blackspot shark or Coates's shark (Carcharhinus coatesi) is a species of requiem shark found off northern Australia (from Shark Bay in Western Australia to Fraser Island in Queensland) and possibly also off the coast of New Guinea. It belongs to a species complex of Blackspot sharks in the familyCarcharhinidae. These sharks are not widely studied due to their cryptic nature, but there was a recent reclassification distinguishing it from the Whitecheek shark (Carcharhinus dussumieri) and the Blackspot Shark (Carcharhinus sealei) in 2012. Much of the existing literature predates this reclassification and groups the Australian blackspot shark with the aforementioned closely related species. (Full article...)
Fedorov's catshark (Apristurus fedorovi) is a shark of the familyPentanchidae, the deepwater catsharks. This shark has oviparousreproduction. This is a very poorly known species, with less than 30 specimens reported in the scientific literature. Almost nothing is known of its biology. This species may be endemic to northern Japanese waters, where it is taken in water around 1,200 m (3937 ft) deep. However, accurate identification of Apristurus species is particularly difficult, and further research is required to determine its geographical and bathymetrical distribution. (Full article...)
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Squalus clarkae, also known as Genie's dogfish, is a species of shark from the Gulf of Mexico and western Atlantic. It was described in 2018 and named in honor of ichthyologistEugenie Clark. It was previously believed to be a part of Squalus mitsukurii, but genetic analysis revealed it to be a distinct species. Individuals are usually between 50 centimetres (20 in) and 70 centimetres (28 in) long. This species is known to be longer in length in comparison to the Squalus Mitsukurii. Their first dorsal fin is also structured differently than the other species in the genus Squalus. (Full article...)
The gulper shark (Centrophorus granulosus) is a long and slender dogfish usually about three feet in length generally found in deep, murky waters all around the world. It is a light grayish brown, palerventrally, with a long snout and large greenish eyes. This deep water shark has two dorsal fins with long, grooved spines and the second dorsal fin smaller than the first. Its upper teeth are blade-like and lower have finely serrated edges. This tertiary consumer feeds on mainly fish such as bony fish, but also cephalopods such as squid and other invertebrates like crustaceans. The gulper shark is currently an endangered species mainly because of exploitation by humans and their abnormally long gestation period and low fecundity, preventing their population from recovering. Because of the depth of their habitat, they are considered little to no threat to humans. (Full article...)
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The broadmouth catshark (Apristurus macrostomus) is a rare species of shark of the familyPentanchidae, the deepwater catsharks. The holotype and only specimen of which was taken from off Zhujiang in the South China Sea, at a depth of 913 m. Its length is around 38 cm. The broadmouth catshark's reproduction is oviparous. Considering the species is not well known, the threats are not known either but may be deepwater fisheries. (Full article...)
The Taiwan spurdog (Squalus formosus) is a species of shark in the genus Squalus. It was accidentally found in Taiwan's Tashi fish market by William Toby White and a colleague of the CSIRO in Hobart, Australia. They named it S. formosus ("Formosa" being a former name for Taiwan). It has also been recorded from the coast of Japan, near Kyushu and Shikoku.
Sharks now identified as Squalus formosus had earlier been classified as Squalus blainville, a species that is no longer considered to occur in Taiwan. Squalus formosus can be morphologically separated from the other three Squalus species found in Taiwanese waters (which are S. brevirostris, S. japonicus and S. mitsukurii); it is morphologically more similar to Squalus albifrons from eastern Australia than the other Taiwanese species. Similarly, genetic methods identify S. albifrons as the closest relative of S. formosus.
It is a medium-sized species of Squalus that can reach at least 81 cm (32 in) TL. (Full article...)
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The brown smooth-hound (Mustelus henlei) is a houndshark of the familyTriakidae. The reproduction of this shark is viviparous. The brown smooth-hound reaches a maximum reported size of 95.0 cm and a minimum of 27.6cm amongst males while females can range from 25.7 cm to 100 cm although males reach their asymptotic length sooner than females. The average size of this species is between 50 and 70 cm and is between 19 and 21 cm at birth. Females at maternity are around 67.6 cm long whereas the average length at maturity is 63.6 cm for males and 65.6 cm for females. This species is a ground shark and has a heterocercal caudal fin bearing an elongate upper lobe, triangular and broad dorsal fins, broad pectoral fins, an inferior mouth, and large eyes, and displays a reddish or bronze coloration from above and a silverish coloration on the underside. The shark is additionally slender, long-snouted, and sharp-toothed. The teeth of the brown smooth-hound often bear a narrow primary cusp and one or two accessory cusplets. (Full article...)
The broadmouth catshark (Apristurus macrostomus) is a rare species of shark of the familyPentanchidae, the deepwater catsharks. The holotype and only specimen of which was taken from off Zhujiang in the South China Sea, at a depth of 913 m. Its length is around 38 cm. The broadmouth catshark's reproduction is oviparous. Considering the species is not well known, the threats are not known either but may be deepwater fisheries. (Full article...)
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The pale spotted catshark (Asymbolus pallidus) is a species of shark belonging to the familyPentanchidae, the deepwater catsharks. this shark is found only off Queensland, at depths of between 225 and 400 m (738 and 1,312 ft). Its length is up to 44 cm (17 in). (Full article...)
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Ginglymostoma unami, also known as the Pacific nurse shark is a nurse shark of the family Ginglymostomatidae. It is found in southeastern coast of Baja California, Mexico to Costa Rica including Gulf of California. It is 2.8 meters long. This species differs from Ginglymostoma cirratum between posterior end of the second dorsal fin and the beginning of the caudal lobe, both being shorter; the new species also differs by the position of the insertion of the first dorsal fin with regard to the pelvic fins and in the form and number of keels on the dermal denticles and teethmorphology. The Ginglymostoma unami was previously recognized as G.cirratum exhibiting a divided distribution of a species in the northern half of the Atlantic Ocean. However, that species is now considered to be restricted to just the Atlantic Ocean. (Full article...)
The bigeye sand tiger (Odontaspis noronhai) is an extremely rare species of mackerel shark in the familyOdontaspididae, with a possible worldwide distribution. A large, bulky species reaching at least 3.6 m (12 ft) in length, the bigeye sand tiger has a long bulbous snout, large orange eyes without nictitating membranes, and a capacious mouth with the narrow teeth prominently exposed. It can be distinguished from the similar smalltooth sand tiger (O. ferox) by its teeth, which have only one lateral cusplet on each side, and by its uniformly dark brown color.
One of the smaller hammerheads, the scoophead measures 150 cm long; adult males measure 90 cm long and adult females 100–133 cm. It is distinguished by its moderately broad, mallet-shaped head (22–33% as wide as the body is long). The forward margin of the head is arched, with weak medial and lateral indentations and no prenarial grooves, traits that this species shares with the scalloped bonnethead (Sphyrna corona). It is distinguished from the scalloped bonnethead by its shorter snout, broadly arched mouth, and deeply concave anal fin. The first dorsal fin is moderately falchate, and the second dorsal fin is as tall as the anal fin. The pelvic fins are not falchate, with a straight to moderately concave rear margin. Its coloration is grey-brown above, light below, with no fin markings.
Off the coast of Trinidad, the scoophead coexists with two other small hammerheads, the bonnethead (Sphyrna tiburo) and the golden hammerhead (S. tudes). These species avoid competition by diet and habitat differences; the scoophead feeds on small elasmobranchs, octopus, squid, and flounders. Like other hammerheads, the scoophead is viviparous, with the pups measuring 34 cm or less at birth. It is taken with bottom longlines, gillnets, and hook and line throughout its range. It is caught commercially and sold as fresh fish or turned into fishmeal. The scoophead is also a common bycatch of the gillnet mackerelfishery off Trinidad. (Full article...)
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The Saldanha catshark (Apristurus saldanha) is a species of shark belonging to the familyPentanchidae, the deepwater catsharks. This catshark is found from Cape Columbine to south of False Bay in South Africa, between 31 and 40°S. Its length is up to 88 cm (35 in). It is a plain, dark grey-brown, stout catshark, with moderately large eyes, a broad snout, and large pectoral fins. (Full article...)
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The fringefin lanternshark (Etmopterus schultzi) is a shark of the familyEtmopteridae found in the western central Atlantic from Texas to Florida, northern Gulf of Mexico, and Mexico. It is endemic to this area. It is a deep water shark and is found about 220 to 915 meters below the surface, on the upper continental slopes of the Gulf. E. schultzi is a small shark, about 27–30 cm long and feeds on squid. It is also bioluminescent, which counter-illuminates it and helps with intraspecific interaction. Due to its limited range and the difficulty of collecting deep water species, it has not been evaluated by the IUCN Red List, but due to recent oil spills in the Gulf of Mexico, it is likely that fringefin lanternsharks have decreased in population. (Full article...)
The blackspot shark (Carcharhinus sealei) is a small species of requiem shark in the family Carcharhinidae found in the tropical Indo-West Pacific Ocean between latitudes 24°N and 30°S, from the surface to a depth around 40 m (130 ft). Its length is a little under one meter (yard) and it is not considered to be dangerous to humans. It feeds mainly on fish, crustaceans, and squid. This shark is also caught in small-scale fisheries for human consumption. (Full article...)
The Arabian catshark (Bythaelurus alcockii) is a species of shark belonging to the familyPentanchidae, the deepwater catsharks. It can grow up to 30 centimetres (12 in) long, and lives in open seas. It is only known from a single specimen, now lost, which was found on the continental slope of the Arabian Sea. (Full article...)
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The zebra shark (Stegostoma tigrinum) is a species of carpet shark and the sole member of the family Stegostomatidae. It is found throughout the tropical Indo-Pacific, frequenting coral reefs and sandy flats to a depth of 62 m (203 ft). Adult zebra sharks are distinctive in appearance, with five longitudinal ridges on a cylindrical body, a low caudal fin comprising nearly half the total length, and usually a pattern of dark spots on a pale background. Young zebra sharks under 50–90 cm (20–35 in) long have a completely different pattern, consisting of light vertical stripes on a brown background, and lack the ridges. This species attains a length of 2.5 m (8.2 ft).
Zebra sharks are nocturnal and spend most of the day resting motionless on the sea floor. At night, they actively hunt for molluscs, crustaceans, small bony fishes, and possibly sea snakes inside holes and crevices in the reef. Though solitary for most of the year, they form large seasonal aggregations. The zebra shark is oviparous: females produce several dozen large egg capsules, which they anchor to underwater structures via adhesive tendrils. Innocuous to humans and hardy in captivity, zebra sharks are popular subjects of ecotourism dives and public aquaria. The World Conservation Union has assessed this species as Endangered worldwide, as it is taken by commercial fisheries across most of its range (except off Australia) for meat, fins, and liver oil. There is evidence that its numbers are dwindling. (Full article...)
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The false catshark or sofa shark (Pseudotriakis microdon) is a species of ground shark in the familyPseudotriakidae, and the sole member of its genus. It has a worldwide distribution, and has most commonly been recorded close to the bottom over continental and insular slopes, at depths of 500–1,400 m (1,600–4,600 ft). Reaching 3.0 m (9.8 ft) in length, this heavy-bodied shark can be readily identified by its elongated, keel-like first dorsal fin. It has long, narrow eyes and a large mouth filled with numerous tiny teeth. It is usually dark brown in color, though a few are light gray.
With flabby muscles and a large oilyliver, the false catshark is a slow-moving predator and scavenger of a variety of fishes and invertebrates. It has a viviparous mode of reproduction, featuring an unusual form of oophagy in which the developing embryos consume ova or egg fragments released by the mother and use the yolk material to replenish their external yolk sacs for later use. This species typically gives birth to two pups at a time. The International Union for Conservation of Nature (IUCN) has assessed the conservation status of the false catshark as Least-concern. While neither targeted by fisheries nor commercially valuable, it is caught incidentally by longlines and bottom trawls, and its low reproductive rate may render it susceptible to population depletion. (Full article...)
The Port Jackson shark (Heterodontus portusjacksoni) is a nocturnal, oviparous (egg laying) type of bullhead shark of the familyHeterodontidae, found in the coastal region of southern Australia, including the waters off Port Jackson. It has a large, blunt head with prominent forehead ridges and dark brown harness-like markings on a lighter grey-brown body, and can grow up to 1.65 metres (5.5 ft) long. They are the largest in the genus Heterodontus.
The Port Jackson shark is a migratory species, traveling south in the summer and returning north to breed in the winter. It feeds on hard-shelled mollusks, crustaceans, sea urchins, and fish. Identification of this species is very easy due to the pattern of harness-like markings that cross the eyes, run along the back to the first dorsal fin, then cross the side of the body, in addition to the spine in front of both dorsal fins. (Full article...)
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The dwarf catshark (Asymbolus parvus) is a species of shark belonging to the familyPentanchidae, the deepwater catsharks. This shark is found only off the coast of Western Australia, at depths between 200 and 400 m (660 and 1,310 ft). Its length is up to 44 cm (17 in). (Full article...)
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Brachaelurus (blind sharks) is the sole genus of sharks in the familyBrachaeluridae in the order Orectolobiformes. Only two extant species of blind sharks occur, both of which are native to shallow coastal waters up to 110 m (360 ft) deep, off the eastern coast of Australia.
They are distinguished by the presence of long barbels, large spiracles, and a groove around the nostrils. They have two dorsal fins, placed close together on the back, and a relatively short tail. Blind sharks have fully functioning eyes, but their name was given to them because when caught by anglers these eyes are closed (probably to protect them).
The green lanternshark (Etmopterus virens) is a species of dogfish shark in the familyEtmopteridae, found in the western central Atlantic Ocean. This species usually occurs on the upper continental slope below a depth of 350 m (1,150 ft). Reaching 26 cm (10 in) in length, the green lanternshark has a slender body with a long, thin tail and low, conical dermal denticles on its flanks. It is dark brown or gray with ventral black coloration, which contain light-emitting photophores that may serve a cryptic and/or social function. Green lanternsharks are thought to be gregarious and may attack their prey, squid and octopus often larger than themselves, in packs. Reproduction is aplacental viviparous, with females giving birth to litters of one to three young. This relatively common shark is an occasional, valueless bycatch of commercial fisheries; currently it does not appear to be significantly threatened by human activities. (Full article...)
The whitetip reef shark (Triaenodon obesus) is a species of requiem shark, in the family Carcharhinidae, and the only member of its genus. A small shark that does not usually exceed 1.6 m (5.2 ft) in length, this species is easily recognizable by its slender body and short but broad head, as well as tubular skin flaps beside the nostrils, oval eyes with vertical pupils, and white-tipped dorsal and caudal fins. One of the most common sharks found on Indo-Pacificcoral reefs, the whitetip reef shark occurs as far west as South Africa and as far east as Central America. It is typically found on or near the bottom in clear water, at a depth of 8–40 m (26–131 ft).
During the day, whitetip reef sharks spend much of their time resting inside caves. Unlike other requiem sharks, which rely on ram ventilation and must constantly swim to breathe, this shark can pump water over its gills and lie still on the bottom. At night, whitetip reef sharks emerge to hunt bony fishes, crustaceans, and octopus in groups, their elongate bodies allowing them to force their way into crevices and holes to extract hidden prey. Individuals may stay within a particular area of the reef for months or years, frequently returning to the same shelter. This species is viviparous, in which the developing embryos are sustained by a placental connection to their mother.
Whitetip reef sharks are rarely aggressive towards humans, though they may investigate swimmers closely. However, spear fishers are at risk of being bitten by one attempting to steal their catch. This species is caught for food, though ciguatera poisoning resulting from its consumption has been reported. The IUCN has assessed the whitetip reef shark as Vulnerable, noting its numbers are dwindling due to increasing levels of unregulated fishing activity across its range. The slow reproductive rate and limited habitat preferences of this species renders its populations vulnerable to overfishing. (Full article...)
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The Pacific angelshark (Squatina californica) is a species of angelshark, family Squatinidae, found in the eastern Pacific Ocean from Alaska to the Gulf of California, and from Ecuador to Chile, although those in the Gulf of California and southeastern Pacific may in fact be separate species. The Pacific angelshark inhabits shallow, coastal waters on sandy flats, usually near rocky reefs, kelp forests, or other underwater features. This species resembles other angel sharks in appearance, with a flattened body and greatly enlarged pectoral and pelvic fins. Characteristic features of this shark include a pair of cone-shaped barbels on its snout, angular pectoral fins, and a brown or gray dorsal coloration with many small dark markings. It attains a maximum length of 1.5 m (4.9 ft).
An ambush predator, the Pacific angelshark conceals itself on the sea floor and waits for approaching prey, primarily bony fishes and squid. Prey are targeted visually and, with a quick upward thrust of the head, snatched in protrusible jaws. Individual sharks actively choose ideal ambush sites, where they stay for several days before moving on to a new one. This species is more active at night than during the day, when it stays buried in sediment and seldom moves. Reproduction is ovoviviparous, with the embryos hatching inside the mother's uterus and being sustained by a yolk sac until birth. Females give birth to an average of six young every spring.
Pacific angelsharks are not dangerous to humans unless provoked, in which case their bite can cause a painful injury. They are valued for their meat and are captured by commercial and recreational fishers across their range. A targeted gillnet fishery for this species began off Santa Barbara, California in 1976 and ended in 1994, after overfishing and new regulations led to its near-collapse. This species is now mainly fished in Mexican waters. The International Union for Conservation of Nature (IUCN) has assessed this species as Near Threatened, as the Californian population is largely protected and recovering, while the impact of Mexican fisheries is unknown. (Full article...)
The Marib Dam (Arabic: سَدّ مَأْرِبSadd Ma'rib, or سُدّ مَأْرِبSudd Ma'rib) is a modern dam blocking the wadi or valley of Adhanah (أَذَنَة, also Dhanahذَنَة) in the Balaq Hills, located in the Ma'rib Governorate in Yemen. The current dam was built in the 1980s and is close to the ruins of the ancient dam, first built in the 8th century BC. It was one of the engineering wonders of the ancient world and a central part of the Sabaean and Himyarite kingdoms around Ma'rib.
Other important ancient dams in Yemen include the Dam of Jufaynah, the Dam of Khārid, the Dam of Aḑraʾah, the Dam of Miqrān and the Dam of Yathʾān. Historically, Yemen has been recognized for the magnificence of its ancient water engineering. From the Red Sea coast to the limits of the Empty Quarter Desert are numerous ruins of small and large dams made of earth and stone.
The Achelous (Greek: Αχελώος, Ancient Greek: ἈχελῷοςAkhelôios), also Acheloos, is a river in Epirus, western Greece. It is 220 km (137 mi) long. It formed the boundary between Acarnania and Aetolia of antiquity. It empties into the Ionian Sea. In ancient times its spirit was venerated as the river god Achelous.
Herodotus, taking notice of the shoreline-transforming power of the Acheloos River, even compared it to the Nile in this respect: :'There are other rivers as well which, though not as large as the Nile, have had substantial results. In particular (although I could name others), there is the Achelous, which flows through Acarnania into the sea and has already turned half the Echinades islands into mainland.' (2.10, trans. Waterfield)
It is said to have been called more anciently Thoas, Axenus and Thestius. (Full article...)
Ayer Itam Dam is a dam in George Town within the Malaysian state of Penang. Located 7.6 km (4.7 mi) southwest of the city centre, the dam impounds the Ayer Itam River to the west of Ayer Itam. At the time of its opening in 1962, it was the largest dam in Malaya, with a capacity of 2.16 billion litres (480,000,000 imp gal; 570,000,000 US gal). (Full article...)
The dam's reservoir has a total capacity of 300,000 m3. The water is transported to the powerhouse through a 12.04 km long tunnel and a 3.65 km long pressure tube. The plant has 3 × 30 MWPelton turbines, with a total installed capacity of 90 MW. The plant has a net level declination of 490.6 m, and a designed flow of 7.33 m3/s per unit.
The plant's total output between 1981 and 2006 was 6600.96 GWh, which amounts to an average annual electricity generation of 264 GWh. (Full article...)
Both the lake and the nearby power station (Sigölduvirkjun[ˈsɪːɣˌœltʏˌvɪr̥cʏn]) take their names from a tuff ridge at about 600 m above sea level where the river Tungnaá once passed through a canyon. Its waters now flow in tubes into the power station, constructed between 1973 and 1977. (Full article...)
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The Golovnaya Dam is an earth-fill embankment dam on the Vakhsh River just east of Sarband in Khatlon Province, Tajikistan. It serves to provide water to a system of irrigation canals and generate hydroelectric power. The first generator was commissioned in 1962 and the last in 1963. Between 1984 and 1989 three of the Kaplan turbines were upgraded from 35 MW to 45 MW. Two of the turbines in the 240 MW power station discharge water into a canal on the left bank of the river. Water from this canal serves to irrigate but also supplies the 29.9 MW Perepadnaya and 15.1 MW Centralnaya Hydroelectric Power Plants located further down. The reservoir has a design storage volume of 96,000,000 m3 (78,000 acre⋅ft) by an estimated 80 percent of this is now silt. (Full article...)
The Al-Wehda Dam (سد الوحدة, Sadd Al-Weḥda, Unity Dam), formerly known as Maqarin Dam, is a 110 m (360 ft) roller-compacted concretegravity dam on the Yarmouk River on the border between Syria and Jordan. It can hold up to 115,000,000 m3 (93,000 acre⋅ft) water and is designed to provide Jordan with water for both human consumption and agriculture. Water from the reservoir is diverted through a diversion weir at Addassiyah downstream of the Al-Wehda dam to the King Abdullah Canal where it is mixed with other freshwater sources. Some of the water from the canal is then pumped to Amman to be used as drinking water, after being treated in the Zai water treatment plant. The discharge of effluents from adjacent agricultural lands has caused algae growth and eutrophication especially in spring. Construction was funded by the Arab Fund for Economic and Social Development (80%), the Abu Dhabi Development Fund (10%) and the Government of Jordan (10%). In February 2004 King Abdullah II of Jordan and Syrian President Bashar al-Assad launched the construction of the dam. Turkey's Ozaltin Company constructed 60 per cent of the dam, while the remaining 40 per cent were carried out by Marwan Alkurdi Company and the National Company for Roads and Bridges.
The sharing of the waters of the Yarmouk River between the two countries is governed by a 1987 treaty that set up a Jordanian-Syrian Yarmouk River Basin Higher Committee. The agreement was renewed in 2001 when the design of the dam was modified, reducing the storage capacity from 480 to 115 million cubic meters, and removing a hydropower plant that had initially been foreseen from the plans. According to a statement made by the Jordanian Minister of Water and Irrigation, Mousa Jamani, in April 2012 Syria violates the water sharing agreement, because Syrian farmers downstream of the dam use more than the 6 million cubic meters per year that they are entitled to for irrigation along the riverbank. The Minister also said that "since the agreement was signed, the number of Syrian dams increased from 26 to 48, while around 3,500 wells were drilled to pump water from the river basin", thus decreasing the amount of water flowing into the dam's reservoir. Until the 1960s, the Yarmouk River’s flow used to reach 16 cubic meters per second, but has since dropped to only one cubic meter per second. (Full article...)
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The Sykia Dam is a mostly constructed but unused earth-filled embankment dam on the Acheloos River along the border of Karditsa and Arta, Greece. The 170 m (560 ft) tall dam is part of the Acheloos River Diversion which is intended to divert a portion of the Acheloos west to irrigate 240,000–380,000 ha (590,000–940,000 acres) in the Thessaly plains. The project includes the Sykia, Messochora, Mouzaki and Pyli Dams along with a 17.4 km (10.8 mi) long channel.
The idea for the Sykia Dam and overall diversion project was first envisioned in the 1930s but a lack of funding precluded construction. Interest in the project was revived in 1984 and construction on the dam began in 1996. Over the next several years there was a series of legal battles that led to final construction stalling, most recently in 2005. Opponents of the scheme cite significant changes to the environment, flooding of villages and that the scheme will divert 600,000,000 m3 (490,000 acre⋅ft) of water annually from the Acheloss. Supporters call on the benefit to the lucrative cotton crops it will help irrigate and the dam's planned 120 MW hydroelectric power plant. (Full article...)
The power station located at the base of the dam will house three 84.33 MWKaplan turbine-generators for an installed capacity of 253 MW. The dam will create a reservoir covering 40 square kilometers.
The project is being developed by Centrales Hidroelectricas de Nicaragua (CHN). Brazil's Eletrobras was to fund the US$1.1 billion under a 20 to 30 year build–operate–transfer (BOT) agreement. First announced in March 2010, preliminary construction (roads, bridges and foundation) was to begin in 2011, and operations on the plant were projected to start by February 2015, after a 4-year-long construction. However, there have been many delays. In 2016, the dam project was indefinitely suspended due to Eletrobras' economic and legal troubles, in connection with the Brazilian economic crisis. The project is still stalled as of January 2020. (Full article...)
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Mai Nefhi (Tigrigna for "Water-Distend?") is both a location near Asmara, Eritrea and the dam after which it was named. The Mai Nefhi dam was completed in 1970, during the reign of Haile Selassie, and remains the main water source for Asmara.
Abardae a town with a population of 3000 residents is located nearby. Eritrea Institute of Technology, the only technical college in the country is located 500m away from Abardae-Mai Nefhi. (Full article...)
The proposed dam became the rallying point for protest in 1986–87 by hundreds of thousands of Latvians resulting with the cancellation of the project, in spite of the vast expenditures already poured into the project. The protest was a precursor of the Latvian Third Awakening. (Full article...)
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Zakučac Hydroelectric Power Plant is a large power plant in Croatia that has four turbines with a nominal capacity of 122 megawatts (164,000 hp) each having a total capacity of 488 megawatts (654,000 hp).
It is a high-pressure diversion plant located at the Cetina River mouth into the sea, near the city of Omiš.
The Gatun Dam is an earthen dam across the Chagres River in Panama, near the town of Gatun. The dam, constructed between 1907 and 1913, is a crucial element of the Panama Canal; it impounds the artificial Gatun Lake, which carries ships 33 kilometres (21 mi) of their transit across the Isthmus of Panama. In addition, a hydro-electric generating station at the dam generates electricity which is used to operate the locks and other equipment in the canal.
Construction of the dam was a great engineering achievement, eclipsed only by the parallel excavation of the Culebra Cut; at the time of completion, the dam was the largest earth dam in the world, and Gatun Lake was the largest artificial lake in the world. (Full article...)
If built, the 57 m high concrete gravity dam will be one of the largest hydropower plants in the country, with an installed electric capacity of 93 MW and an expected annual generation of 322 GWh. (Full article...)
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The Manuel Piar Hydroelectric Power Plant (Tocoma Dam) is a stalled hydroelectric development project in the Lower Caroní River Basin of Venezuela. The project, started in 2006, includes the installation of 2,320 megawatts (3,110,000 hp) MW to generate annual average energy of 12,100 gigawatt-hours (44,000 TJ). As of 2019, the project is unfinished.
The project was awarded to OIV consortium, consisting of Odebrecht (50%), Salini Impregilo (40%) and Vinccler (10%), with an initial budget US$3,061 mil. Ten Kaplan generator units, of 230 megawatts (310,000 hp), manufactured by an Argentinian company IMPSA [es], were predicted to begin operations between 2012 and 2014. These units had the world record as of 2012 in power generation at nominal head for Kaplan turbines. The diameter of the runner is 8.6 metres (28 ft) and nominal head is 34.65 metres (113.7 ft) with claimed output up to 232 megawatts (311,000 hp).
The first generator was installed but not yet commissioned in April 2012. Behind schedule, the dam began to impound its reservoir on 16 November 2015. The budget tripled to $9,4 billion in 2017, as of 2019 the project is still unfinished. Odebrecht spent between 2007 and 2015 at least $118 million on bribes related to the project. (Full article...)
The dam was constructed in August 1956 and opened in May 1960 under the government-owned National Power Corporation (NAPOCOR), three years after its sister facility, the Ambuklao Dam. It is located 31 kilometres (19 mi) southeast of Baguio and 19 kilometres (12 mi) downstream of Ambuklao Dam within the Upper Agno River Basin Resource Reserve. Improvement of the dam is ongoing, after it received heavy damage during the 1990 Luzon earthquake, and its installed capacity of 100 MW is being upgraded to 140MW.
The Nadarivatu Dam, also known as the Korolevu Dam, is a concrete gravity dam on the upper reaches of the Sigatoka River in Nadarivatu District of Nadroga-Navosa Province, Fiji. The primary purpose of the dam is to generate hydroelectric power in a 41.7 megawatts (55,900 hp) run-of-the-river scheme. The Nadarivatu Hydropower Scheme was first identified in 1977 during a hydropower study. Detailed plans for the project were developed in 2002 and major construction began in 2009. The power station was commissioned on 7 September 2012 but an inauguration ceremony led by Prime Minister Frank Bainimarama was held a week later on 14 September. Funding and loans for the project was provided by several organizations to include the China Development Bank (US$70 Million), Fiji Electricity Authority bonds (US$50 million), ADZ Bank (US$30 million). The 40 m (130 ft) tall dam diverts water from the Sigatoka River through a 3,225 metres (10,581 ft) long headrace/penstock tunnel to a power station along the Ba River to the southwest. The power station contains two 20.85 megawatts (27,960 hp) Pelton turbine-generators. The drop in elevation between the reservoir and the power station affords a gross hydraulic head (water drop) of 335.7 metres (1,101 ft). (Full article...)
The Wadi Wishka Dam is a concrete-face rock-fill embankment dam located on Wadi Wishka, 29 km (18 mi) southwest of Sokna in the Fezzan region of Libya. The primary purpose of the dam is flood control and water. Construction on the dam began in 2004 and it was completed in 2006 at a cost of US$5 million. (Full article...)
Bratsberg Power Station (Bratsberg kraftverk) is a hydroelectricpower station located in Trondheim in Sør-Trøndelag County, Norway, owned by Statkraft. It operates at an installed capacity of 124 MW, with an average annual production of 650 GWh. The power plant is fed from the Selbusjøen reservoir, connected with a 12 km long tunnel, offering a gross head of 147 m. The power plant has two Francis turbines. (Full article...)
Weija Dam is a dam on the Densu River which supports the main water treatment plant for Accra in the Greater Accra Region of Ghana. It is operated by the Ghana Water Company.This supplies about 80 percent of the potable water for the entire city of Accra and its surrounding environs. Its construction began in 1974 and was completed in 1978 by Messrs Tahi, an Italian Company. (Full article...)
The dam would be 103 metres (338 ft) high and flood approximately 97 square kilometres (24,000 acres) of the Zambezi valley. The estimated cost of the project is US$4.2 billion. Once the dam is completed, it is expected that most of the generated power will be sold to South Africa, because of the lack of transmission infrastructure in Mozambique.
The proposed dam is highly controversial because it would force the relocation of 1,400 families, and affect the livelihoods of a further 200,000 people downriver. Because the dam would be operated on a peaking basis, large daily fluctuations in river flow would ruin existing irrigation systems and affect aquaculture in the river's extensive delta. The United Nations has described in 1984 the Cahora Bassa existing dam as the "least environmentally acceptable major dam project in Africa."
In 2015, the Mozambique government announced it would start construction of the dam. The construction was contracted to Camargo Corrêa of Brazil, Insitec of Mozambique, and Electricidade de Moçambique. In 2020, Mozambique President Filipe Nyusi wished construction of the dam started before 2024.
The concrete gravity dam has a height of 90 m (300 ft) and a length of 800 m (2,600 ft). The dam's reservoir has a surface area of 135 km2 (52 sq mi) and a capacity of 2,180,000 cubic metres (77,000,000 cu ft).
The hydroelectric power plant was fitted with 2 x 67.5 MWeFrancis turbines with a total capacity of 135 Mwe. Major maintenance work carried out between 2003 and 2007 included replacing the turbines with 2 x 85 MWe units with a total capacity of 170 MWe, which generate 488 GWh per year. (Full article...)
It uses water provided by three reservoirs high up in the Faatautia Valley, above the commune. Each reservoir is created by an embankment dam. Hitia'a 2 Dam at , which lies at an elevation of 637 m (2,090 ft) above sea level, is 19 m (62 ft) tall. It withholds a reservoir of 110,000 m3 (89 acre⋅ft). Next, at an elevation of 530 m (1,740 ft), Hitia'a 3 Dam at is also 19 m (62 ft) high but withholds a larger reservoir of 600,000 m3 (490 acre⋅ft). Finally, Hitia'a 1 Dam at lies at 511 m (1,677 ft) above sea level, is 10 m (33 ft) tall, and withholds a reservoir of 11,000 m3 (8.9 acre⋅ft). Water from the reservoirs is sent to the power station via a 11.5 km (7.1 mi) long penstock. The power station contains an array of six Pelton turbine-generators which include a 300 kW, 140 kW, 100 kW, 1 MW and two 3 MW units. (Full article...)
It uses water provided by five reservoirs high up in the Papenoo Valley, above the commune. Each reservoir is created on the Papenoo River or a tributary by an embankment dam. From highest in elevation to lowest; Vaitapaa Dam at , which lies at an elevation of 411 m (1,348 ft) above sea level, is 15 m (49 ft) tall. It withholds a reservoir of 8,000 m3 (6.5 acre⋅ft). Next, at an elevation of 400 m (1,300 ft), Tahinu Dam, at is 33 m (108 ft) high and withholds a larger reservoir of 1,500,000 m3 (1,200 acre⋅ft). It is the tallest dam in Tahiti. Moving down is Vainavenave Dam at which lies at 399 m (1,309 ft) above sea level, is 29 m (95 ft) tall, and withholds a reservoir of 150,000 m3 (120 acre⋅ft). Fourth down the valley is the Vaituoru Dam at an elevation of 200 m (660 ft) with a reservoir capacity of 100,000 m3 (81 acre⋅ft). It is located at . Finally is the Tevaiohiro Dam at 85 m (279 ft) above sea level with a reservoir volume of 150,000 m3 (120 acre⋅ft). It is located at .
Water from the reservoirs is sent to three separate power stations via 25.5 km (15.8 mi) of penstock. The power station highest in elevation, Papenoo 1 contains four 4 MW Pelton-turbine-generators and is located at . Next downstream is Papenoo 2 at which contains one 4 MW Pelton turbine-generators. Lastly, Papenoo 3 contains two 4 MW Pelton turbine-generators and is located at . (Full article...)
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The Achelous (Greek: Αχελώος, Ancient Greek: ἈχελῷοςAkhelôios), also Acheloos, is a river in Epirus, western Greece. It is 220 km (137 mi) long. It formed the boundary between Acarnania and Aetolia of antiquity. It empties into the Ionian Sea. In ancient times its spirit was venerated as the river god Achelous.
Herodotus, taking notice of the shoreline-transforming power of the Acheloos River, even compared it to the Nile in this respect: :'There are other rivers as well which, though not as large as the Nile, have had substantial results. In particular (although I could name others), there is the Achelous, which flows through Acarnania into the sea and has already turned half the Echinades islands into mainland.' (2.10, trans. Waterfield)
It is said to have been called more anciently Thoas, Axenus and Thestius. (Full article...)
The Néstor Kirchner Dam, formerly known as Condor Cliff Dam, is a concrete-face rock-fill dam being built on the Santa Cruz River about 180 km (110 mi) west of Puerto Santa Cruz in Santa Cruz Province, Argentina. It was renamed after the former president Néstor Kirchner, born in Santa Cruz. A consortium led by China's Gezhouba Group was awarded the contract to build the Néstor Kirchner Dam and Jorge Cepernic Dam downstream in August 2013. The consortium will also fund the construction. Both dams are expected to cost nearly US$4.8 billion. The dam is being built by Eling Ingeniería, the successor of Electroingeniería of Osvaldo Acosta and Gerardo Ferreyra. The primary purpose of the dam is hydroelectric power generation and its power station will have an installed capacity of 1,140 megawatts (1,530,000 hp).
In July 2015 machines arrived in Santa Cruz for the construction of the dams.
In December 2016 Supreme Court of Argentina decided to suspend work on the dam.
In December 2023 construction was stopped awaiting funding from China. (Full article...)
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Buhisan Dam is a dam located in Buhisan, Cebu City, Philippines. It is one of the main source of water for Cebu City and Metro Cebu. Part of Central Cebu Protected Landscape, Buhisan Dam is situated in the mountains of Barangay Buhisan behind Labangon, Cebu. Built in 1911-1912 and maintained by the Metro Cebu Water District, it is being developed into an eco-tourism location. It supplies five percent of Metropolitan Cebu Water District's (MCWD) current water capacity. (Full article...)
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The Lost Caracoles Dam, or Caracoles Dam is a concrete-face rock-fill dam on the San Juan River about 44 kilometres (27 mi) west of San Juan in San Juan Province, Argentina. The purpose of the dam is to provide water for irrigation and the generation of hydroelectric power. The 136-metre (446 ft) tall dam supports a 126 megawatts (169,000 hp) power station and together with the Punta Negra Dam downstream, it provides for the irrigation of 15,000 hectares (37,000 acres). Construction began in 2004 and the dam and power station were completed in 2009. (Full article...)
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Gajah Mungkur Reservoir (Dam) (Indonesian: Waduk Gajah Mungkur) is a water reservoir located at Pokohkidul in the Wonogiri Regency, Central Java, of Indonesia. It was constructed by redirecting the Bengawan Solo River, the longest in the Java Islands, which originates from The Gajah Mungkur Mountain. The maximum inundation area of Gajah Mungkur Reservoir is 8,800 hectares and covers the seven subdistricts of Wonogiri, Ngadirojo, Nguntoronadi, Baturetno, Giriwoyo, Eromoko, and Wuryantoro.
The reservoir is used for irrigation, hydroelectric power, source of drinking water, tourism, aquaculture, and fisheries. Various fish may be found in the water, including parrotfish, wader pari, tawes, and patin jambal. (Full article...)
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The Chapada do Araripe, also known as the Serra do Araripe, is a chapada (plateau) in northeastern Brazil. The chapada forms the boundary of Ceará and Pernambuco states, and forms the watershed between the Jaguaribe River of Ceará, which flows northward into the Atlantic, and the much larger basin of the São Francisco River of Pernambuco and neighboring states, which drains eastward into the Atlantic. The Santana Formation, which is rich with fossils from the early Cretaceous, lies at the base of the chapada. The Araripe manakin (Antilophia bokermanni), a bird only described in 1998, is endemic to Chapada do Araripe. (Full article...)
The mountain runs from northeast to southwest, extending from the Juniata River at Millerstown in the north to the end of Cove Mountain at Cowans Gap in the south. Part of it forms the border between Fulton and Franklin counties.
The Balkan mountain range is located in the eastern part of the Balkans in Southeastern Europe. The range is conventionally taken to begin at the peak of Vrashka Chuka on the border between Bulgaria and Serbia. It then runs for about 560 kilometres (350 mi), first in a south-easterly direction along the border, then eastward across Bulgaria, forming a natural barrier between the northern and southern halves of the country, before finally reaching the Black Sea at Cape Emine. The mountains reach their highest point with Botev Peak at 2,376 metres (7,795 ft).
In much of the central and eastern sections, the summit forms the watershed between the drainage basins of the Black Sea and the Aegean. A prominent gap in the mountains is formed by the predominantly narrow Iskar Gorge, a few miles north of the Bulgarian capital, Sofia. The karst relief determines the large number of caves, including Magura, featuring the most important and extended European post-Palaeolithic cave painting, Ledenika, Saeva dupka, Bacho Kiro, etc. The most notable rock formation are the Belogradchik Rocks in the west.
There are several important protected areas: Central Balkan National Park, Vrachanski Balkan, Bulgarka and Sinite Kamani, as well as a number of nature reserves. The Balkan Mountains are remarkable for their flora and fauna. Edelweiss grows there in the region of Kozyata stena. Some of the most striking landscapes are included in the Central Balkan National Park with steep cliffs, the highest waterfalls in the Balkans and lush vegetation. There are a number of important nature reserves such as Chuprene, Kozyata stena and others. Most of Europe's large mammals inhabit the area including the brown bear, wolf, boar, chamois and deer.
The mountains are the source of the name of the Balkans (sometimes considered as a distinct peninsula or region). In Bulgarian and Serbian the mountains are also known as Стара планинаStara planina (pronounced in Bulgarian as [ˈstarɐpɫɐniˈna] and in Serbian as [stâːraːplanǐna]), a term whose literal meaning is 'old mountain'. (Full article...)
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Fansipan (Vietnamese: Phan Xi Păng, listen) is a mountain in Vietnam. Its height was 3,143 metres (10,312 ft) in 1909, and it presently stands at 3,147.3 metres (10,326 ft). It is the highest mountain on the Indochinese peninsula (comprising Vietnam, Laos, and Cambodia), hence its nickname, "the Roof of Indochina". It is located in the Lào Cai province of the Northwest region of Vietnam, nine kilometres (5+1⁄2 miles) southwest of Sa Pa, in the Hoang Lien Son mountain range. Administratively, it is shared between Tam Đường District, Lai Châu and Sa Pa town. (Full article...)
The Lechtal Alps (German: Lechtaler Alpen) are a mountain-range in western Austria, and part of the greater Northern Limestone Alps range. Named for the river Lech which drains them north-ward into Germany, the Lechtal Alps occupy the Austrian states of Tyrol and Vorarlberg and are known for their diverse rock structure.
The Sweet Grass Hills (Blackfoot: kátoyissiksi, Cheyenne: vé'ho'ôhtsévóse, Kalispel-Pend d'Oreille: ččaɫalqn, "three peaks") are a small group of low mountains rising more than 3,000 feet (910 m) above the surrounding plains southwest of Whitlash, Montana, in Liberty and Toole County, Montana. The tallest point in the hills is West Butte at 6,983 feet (2,128 m). Quite prominent in the local area, they are clearly visible from US Highway 2 to the south, I-15, and can sometimes be seen as far North as the Crowsnest Highway (Highway 3) near Medicine Hat in Alberta as well as from the West, near Glacier National Park and Browning, Montana. Visibility may vary depending on local air temperatures or heat domes that may increase or decrease the apparent height of the features. Other named peaks in the small group are Gold Butte (6,512 ft [1,985 m]), East Butte (with two peaks, the taller of which is Mount Brown at 6,958 ft [2,121 m]), and Mount Lebanon (5,807 ft [1,770 m]). The Sweet Grass Hills are an example of the island ranges that dot the central third portion of the state of Montana. These island ranges, completely surrounded by the 'sea' of plains and not geographically (or often geologically) part of the Rocky Mountains to the west, are "biological hotspots", containing more species than the prairie below. (Full article...)
The name for the mountain ranger was first proposed by then University of Wisconsin geologist, Eliot Blackwelder. It is named after A. J. Brabazon, who created the first topographic map of the ranger in 1895. (Full article...)
The Andes are the highest mountain range which is outside of Asia. The range's highest peak, Argentina's Aconcagua, rises to an elevation of about 6,961 m (22,838 ft) above sea level. The peak of Chimborazo in the Ecuadorian Andes is farther from the Earth's center than any other location on the Earth's surface, due to the equatorial bulge resulting from the Earth's rotation. The world's highest volcanoes are in the Andes, including Ojos del Salado on the Chile-Argentina border, which rises to 6,893 m (22,615 ft).
The range is older than the other major mountain range in North America, the Rocky Mountains of the west. Some of the outcrops in the Appalachians contain rocks formed during the Precambrian era. The geologic processes that led to the formation of the Appalachian Mountains started 1.1 billion years ago. The first mountain range in the region was created when the continents of Laurentia and Amazonia collided, creating a supercontinent called Rodinia. The collision of these continents caused the rocks to be folded and faulted, creating the first mountains in the region. Many of the rocks and minerals that were formed during that event can currently be seen at the surface of the present Appalachian range. Around 480 million years ago, geologic processes began that led to three distinct orogenic eras that created much of the surface structure seen in today's Appalachians. During this period, mountains once reached elevations similar to those of the Alps and the Rockies before natural erosion occurred over the last 240 million years leading to what is present today.
The Appalachian Mountains are a barrier to east–west travel, as they form a series of alternating ridgelines and valleys oriented in opposition to most highways and railroads running east–west. This barrier was extremely important in shaping the expansion of the United States in the colonial era.
The Chapada das Mangabeiras is a mountain range in central Brazil. The range runs northwest–southeast, and separates the basin of the Tocantins River to the southwest from the upper basin of the Parnaiba River to the northeast. The range also forms the boundary between Tocantins state and the states of Maranhão and Piauí. The highest points of both states are located there. The points are unnamed locations, one measuring 804 meters (Maranhão), and the other, 860 meters (Piauí). (Full article...)
The SEIR is the spreading centre closest to the Kerguelen and Amsterdam–Saint-Paulhotspots. The SEIR has an intermediate full spreading rate of 65 mm/a (2.6 in/year), and, because Antarctica is virtually stationary, this results in a northward ridge migration of half that rate. Spreading rates along the SEIR varies from 69 mm/a (2.7 in/year) near 88°E to 75 mm/a (3.0 in/year) near 120°E. (Full article...)
Other mountain groups of similar geological structure are spread along the River Piave to the east—Dolomiti d'Oltrepiave; and far away over the Adige River to the west—Dolomiti di Brenta (Western Dolomites). A smaller group is called Piccole Dolomiti (Little Dolomites), between the provinces of Trentino, Verona and Vicenza.
The Livingston Range is a mountain range located primarily in Glacier National Park in the U.S. state of Montana, and in the extreme southeastern section of the Canadian province of British Columbia. The range is 36 miles (58 km) long and 28 miles (45 km) wide. Over 15 summits exceed 9,000 ft (2,700 m) above sea level, and the highest point is Kintla Peak at 10,101 feet (3,079 m). (While these elevations are not particularly high for North American mountains, they are high compared to the roughly 4,000 foot (1,200 m) elevation of the nearby valleys, making for particularly dramatic peaks.)
The Livingston Range was uplifted beginning 170 million years ago when the Lewis Overthrust fault pushed an enormous slab of precambrian rocks 3 mi (4.8 km) thick, 50 miles (80 km) wide and 160 miles (260 km) long over newer rocks of the cretaceous period. (Full article...)
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Snowdonia, or Eryri (pronounced[ɛrəri]ⓘ), is a mountainous region and national park in North Wales. It contains all 15 mountains in Wales over 3000 feet high, including the country's highest, Snowdon (Yr Wyddfa), which is 1,085 metres (3,560 ft) tall. These peaks are all part of the Snowdon, Glyderau, and Carneddau ranges in the north of the region. The shorter Moelwynion and Moel Hebog ranges lie immediately to the south.
The national park has an area of 823 square miles (2,130 km2) (the fourth-largest in the UK), and covers most of central and southern Gwynedd and the western part of Conwy County Borough. This is much larger than the area traditionally considered Snowdonia, and in addition to the five ranges above includes the Rhinogydd, Cadair Idris, and Aran ranges and the Dyfi Hills. It also includes most of the coast between Porthmadog and Aberdyfi. The park was the first of the three national parks of Wales to be designated, in October 1951, and the third in the UK after the Peak District and Lake District, which were established in April and May 1951 respectively. The park received 3.89 million visitors in 2015. (Full article...)
The mountain range is the home of the Virginia Outdoors Foundation's Preserve at Bull Run Mountains, which is a state-designated Natural Area Preserve dedicated to the scientific and educational potential of the region. The Preserve at Bull Run Mountains has over seven miles of trails that are open to the public on Fridays, Saturdays, and Sundays - year round.
The mountain range also holds several communities of residents, which includes the Bull Run Mountain Estates.
The Blue Mountains are the longest mountain range in Jamaica. They include the island's highest point, Blue Mountain Peak, at 2256 m (7402 ft). From the summit, accessible via a walking track, both the north and south coasts of the island can be seen. On a clear day, the outline of the island of Cuba, 210 km (130 mi) away, can also be seen. The mountain range spans four parishes: Portland, St Thomas, St Mary and St Andrew. (Full article...)
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The Müller Mountains (Indonesian: Pegunungan Muller) are a mountain range in Central Borneo. The mountains extend along the northern border of Kalimantan, the Indonesia-administered parts of Borneo. The mountains are the source of the Kapuas River. The range is named after Georg Müller, a German engineer who traversed the mountains in the 1820s. (Full article...)
The Kakanui Range (or Kakanui Mountains) is a range of high hills located inland from Oamaru in the South Island of New Zealand. The range forms a boundary between the valley of the Waitaki River to the north and the high plateau known as the Maniototo and the upper watershed of the Taieri River to the southwest.
The western Kakanui Range is crossed by road at Danseys Pass, which has a saddle at 935 m (3,068 ft). The eastern portions start to the north east of The Pigroot and Pigroot Hill to the east of the road is a foothill of the range. (Full article...)
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The Cordillera Occidental (English: Western Ranges) is the lowest in elevation of the three branches of the Colombian Andes. The average altitude is 2,000 m (6,600 ft) and the highest peak is Cerro Tatamá at 4,100 m (13,500 ft). The range extends from south to north dividing from the Colombian Massif in Nariño Department, passes north through Cauca, Valle del Cauca, Risaralda, Chocó, and Caldas Departments to the Paramillo Massif in Antioquia and Córdoba Departments. The cordillera is paralleled on the east by the Cauca river. From this massif the range divides further to form the Serranías de Ayapel, San Jerónimo and Abibe. Only to recede into the Caribbean plain and the Sinú River valley.
It is a direct continuation of Cordillera Occidental of Ecuador. (Full article...)
The Selenite Range is a mountain range in western Pershing County, Nevada. The range is a north–south trending feature approximately 27 miles (43 km) long and 4 miles (6.4 km) wide.
The Fox Range lies to the west across the San Emidio Desert valley and the south end of the Black Rock Desert playa. Gerlach and Empire are two communities on the foothills and just to the northwest of the range. These communities supported the gypsum mines in the range during their active period. The large Empire gypsum quarry lies just west of Luxor Peak at 40° 30' N; 119° 18' W just 1.2 mi (1.9 km) northwest of Kumiva Peak. The range was named for deposits of selenite, a variety of gypsum.
The Samnaun Alps are separated from the Sesvenna Alps in the south by the Engadine Valley; from the Silvretta Alps in the west by the Fimber Pass; from the Verwall Alps and the Lechtal Alps in the north by the Paznauntal; from the Ötztal Alps in the east by the Inn valley. All the range is drained by the river Inn, through the Trisanna, Schergenbach, Brancla and Fimbabach. (Full article...)
The H. H. Benedict range is part of the northernmost mountain system in the world. The area where its ridges rise is barren and uninhabited. (Full article...)
It consists of a larger ridge of Bukowica with summits as Skibce (776 m. above the sea level ) in the north-west and Tokarnia (777 m. above the sea level ) in the south-east and the smaller range of Kamien Peak (718 m. above the sea level ). Bukowica is rather a monotonous mountainous bank and is heavily except Tokarnia covered with forest it has a panoramic view in all directions. The southern part is a steep rocky wall, while the other side consist of less steep rocky fields.
The Rio Grande de Loíza, which is one of the largest rivers in Puerto Rico, has its sources in this range within the municipality of San Lorenzo. The La Plata River flows through the Cayey Valley where the town of Cayey is located on the northern slope of the range. There are tobacco and coffee crops in the area. ('Full article...)
The mountains are named for SergeantNathaniel Hale Pryor, a member of the Lewis and Clark Expedition who vainly pursued horses stolen from the expedition in the area. The Crow Tribe, a Native American tribe which lived nearby, called the mountains Baahpuuo Isawaxaawuua ("Hitting Rock Mountains") because of the abundance of flint there (which was chipped into arrowheads).
According to Crow Tribe folklore, Little People (a race of 18 in [46 cm]-high dwarf-like people with spiritual powers) lived in these mountains. (Full article...)
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Alagalla (Sinhala: අලගල්ල, literal translation: Tuber rock) Mountain Range is situated at the boundaries of the Central and Sabaragamuwa Provinces in Sri Lanka. Along with the surrounding Bathalegala (බතලේගල) also known as Bible Rock, Uthuwankanda (උතුවන්කන්ද), Devanagala (දෙවනගල), Ambuluwawa (අම්බුළුවාව), Knuckles Mountain Range and Hanthana (හන්තාන) Mountain Range, Alagalla mountain has served as a natural defense location for nearly five centuries (1505–1948) against the Portuguese, Dutch and English invasions aimed at the Kandyan Kingdom. (Full article...)
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The Serra Geral (General Mountains) is a mountain range in southern Brazil, constituting the southern portion of the Serra do Mar system which runs along Brazil's southeastern coast. The Serra Geral runs parallel to the Atlantic coast in Santa Catarina and northern Rio Grande do Sul states, separating a narrow coastal plain from an interior plateau. The coastal plain is characterized by short rivers and frequent lagoons and bays, and lies within the humid tropical Serra do Mar coastal forestsecoregion.
The plateau to the west of the range is drained by tributaries of the Uruguay River, including the Pelotas and Canoas, and by the Jacuí River and its tributaries, which drains south into the Lagoa dos Patos of Rio Grande do Sul.
The Britannia Range is a small mountain range of the Coast Mountains that runs along the eastern shore of Howe Sound just north of Vancouver, British Columbia, Canada. It is a subrange of the Pacific Ranges and often considered part of the North Shore Mountains. The range is bounded by the Howe Sound to the west, the Stawamus River to the north, Loch Lomond on the upper Seymour River to the east, and Deeks Lake to the south. However, some official maps extend the range further south of these boundaries and many local sources such as hiking guidebooks will often include all of the peaks along the Howe Sound between Deeks Lake and Cypress Mountain as part of the range.
The geology of the Britannia Range is different to the surrounding highly granitic North Shore Mountains due to the high prevalence of volcanic rock (such as at Watts Point volcanic centre) and sedimentary rock like sandstone and shale.
The Cascade Range or Cascades is a major mountain range of western North America, extending from southern British Columbia through Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as many of those in the North Cascades, and the notable volcanoes known as the High Cascades. The small part of the range in British Columbia is referred to as the Canadian Cascades or, locally, as the Cascade Mountains. The highest peak in the range is Mount Rainier in Washington at 14,411 feet (4,392 m). The Cascades are part of the Pacific Ocean's Ring of Fire, the ring of volcanoes and associated mountains around the Pacific Ocean. All of the eruptions in the contiguous United States over the last 200 years have been from the Cascade Volcanoes. The two most recent were Lassen Peak from 1914 to 1921 and a major eruption of Mount St. Helens in 1980. Minor eruptions of Mount St. Helens have also occurred since, most recently from 2004 to 2008. The Cascade Range is a part of the American Cordillera, a nearly continuous chain of mountain ranges (cordillera) that form the western "backbone" of North, Central, and South America.
{{ Transclude list item excerpts as random slideshow | List of dams and reservoirs | section=Africa | sectiononly=yes }} Should pick only the international dams
The Osborne Dam site on the Odzi River, Zimbabwe, was identified in the 1950s by the planning engineers of the Ministry of Water. Cored drilling investigations on the two possible alignments were completed in the 1960s. After the completion of Mazvikadei dam [1985–'88] with Italian financial aid, further funding became available for the project and when the 10 000 hectares of potential irrigable land was identified downstream the project was approved in 1989 by the multi-ministry irrigation committee of the Zimbabwe Government. (Full article...)
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Mai Nefhi (Tigrigna for "Water-Distend?") is both a location near Asmara, Eritrea and the dam after which it was named. The Mai Nefhi dam was completed in 1970, during the reign of Haile Selassie, and remains the main water source for Asmara.
Abardae a town with a population of 3000 residents is located nearby. Eritrea Institute of Technology, the only technical college in the country is located 500m away from Abardae-Mai Nefhi. (Full article...)
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The Bui Dam is a 400-megawatt (540,000 hp) hydroelectric project in Ghana. It is built on the Black Voltariver at the Bui Gorge, at the southern end of Bui National Park. The project was a collaboration between the government of Ghana and Sino Hydro, a Chinese state-owned construction company. Construction on the main dam began in December 2009. Its first generator was commissioned on 3 May 2013, and the dam was inaugurated in December of the same year.
Bui is the second largest hydroelectric generating plant in the country after the Akosombo Dam. The reservoir flooded about 20% of the Bui National Park and impacted the habitats for the rare black hippopotamus as well as a large number of wildlife species. It required the resettlement of 1,216 people, and affected the lives and livelihoods of many more. (Full article...)
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The Von Bach Dam (originally the Sartorius von Bach Dam) is a rock-fill embankment dam on the Swakop River near Okahandja in the Otjozondjupa Region of Namibia. Built in 1968 and commissioned in 1970, the dam provides Namibia's capital of Windhoek with much of the city's water. It also supplies Okahandja. The dam has a capacity of 48.56 million cubic metres (63,510,000 cu yd). Water from the reservoir is sent directly to a water treatment plant downstream. The treatment plant was completed in 1971 and upgraded in 1997. (Full article...)
The Kariba Dam is a double curvature concrete arch dam in the Kariba Gorge of the Zambezi river basin between Zambia and Zimbabwe. The dam stands 128 metres (420 ft) tall and 579 metres (1,900 ft) long. The dam forms Lake Kariba, which extends for 280 kilometres (170 mi) and holds 185 cubic kilometres (150,000,000 acre⋅ft) of water. (Full article...)
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The Tokwe Mukosi Dam is a concrete-face rock-fill dam on the Tokwe River, just downstream of its confluence with the Mukosi River, about 72 kilometres (45 mi) south of Masvingo in Masvingo Province, Zimbabwe. It is 90.3 metres (296 ft) tall and creates a 1,750,000,000 m3 (1,420,000 acre⋅ft) reservoir, the largest inland dam in the country. The associated hydroelectric power station has a 12 megawatts (16,000 hp) installed capacity.
Construction on the dam began in June 1998 but stalled in 2008. Salini Impregilo began to finish the dam in 2011. Heavy flooding in February 2014 caused a partial failure on 4 February, on the downstream face of the dam. By late February the dam had not been fully breached but the unplanned rising reservoir behind the dam caused evacuations upstream. Both upstream and downstream, over 20,000 people were evacuated. Construction of the dam was suspended in June 2014 due to a lack of funding. In May 2016 the government released $35 million to Salini Impregilio to enable the Italian contractor resume construction work that stopped two years ago owing to payment problems. The Dam was eventually completed in December 2016 and commissioned in May 2017. (Full article...)
Lake Mutirikwi, originally known as Lake Kyle or Kyle Dam, lies in south eastern Zimbabwe, south east of Masvingo. It is thought to have been named after Kyle Farm which occupied most of the land required for the lake, which in turn was named after the Kyle district in Scotland from which the pioneer of the Lowveld, Tom Murray MacDougall came originally.
The lake covers about 90 km2 (35 sq mi) and was created in 1960 with the construction of the Kyle Dam on the Mutirikwi River. The dam was built by Concor to provide water to the farming estates on the lowveld to the southwest, around the town of Triangle, where the main crop has been sugar cane.
In the 1980s, drought drastically lowered the water level in the lake, but during the 1990s it recovered. The level fluctuates widely due to irrigation demands and the seasonal rainfall. (Full article...)
The Kandadji Dam, is a large multipurpose dam under construction on the Niger River. The site is situated near the small town of Kandadji, Tillabéri Department, Tillabéri Region, Niger, 180 km northwest of the capital Niamey. It is being built by the Haut Commissariat à l'Aménagement de la Vallée du Niger (High Commission for Niger Valley), a public body under the Primer Minister's Office.
The dam will generate hydropower and is control the flow of the Niger River, holding water during the dry season to maintain a minimum flow and making downstream irrigation possible. The project is formally named the Kandadji Programme for Ecosystem Regeneration and Niger River Development (Programme Kandadji de Régénération des Ecosystèmes et de Mise en Valeur du Fleuve Niger). (Full article...)
The Antelomita Hydroelectric Power Station is located in the rural commune Anjeva Gara of the Analamanga Region, Madagascar. The hydroelectric power station comprises two parts, Antelomita I and II. Both are adjacent to one another on separate water falls along the Ikopa River. Each water fall is dammed and water is diverted to the power station; each of which contains three 1.4 megawatts (1,900 hp) generators. The first two were commissioned in 1930, the second two in 1952 and the final two in 1953. Both stages have an installed capacity of 8.4 megawatts (11,300 hp). They were built by a French firm but are now owned and operated by Jirama. The Tsiazompaniry and Mantasoa Dams upstream regulate water to the power station.
The Von Bach Dam (originally the Sartorius von Bach Dam) is a rock-fill embankment dam on the Swakop River near Okahandja in the Otjozondjupa Region of Namibia. Built in 1968 and commissioned in 1970, the dam provides Namibia's capital of Windhoek with much of the city's water. It also supplies Okahandja. The dam has a capacity of 48.56 million cubic metres (63,510,000 cu yd). Water from the reservoir is sent directly to a water treatment plant downstream. The treatment plant was completed in 1971 and upgraded in 1997. (Full article...)
The Maguga Dam is a dam on the Komati River in Eswatini. It is 115 metres (377 ft) high and is located about 12 kilometres (7.5 mi) south of Piggs Peak. It was built as a joint project of the governments of South Africa and Eswatini. As of 2005, it was the largest public works project ever undertaken by Eswatini. The dam was completed in mid-2001. (Full article...)
The Aswan Low Dam or Old Aswan Dam is a gravity masonrybuttress dam on the Nile River in Aswan, Egypt. The dam was built by the British at the former first cataract of the Nile, and is located about 1000 km up-river and 690 km (direct distance) south-southeast of Cairo. When initially constructed between 1899 and 1902, nothing of its scale had ever been attempted; on completion, it was the largest masonry dam in the world. The dam was designed to provide storage of annual floodwater and augment dry season flows to support greater irrigation development and population growth in the lower Nile. The dam, originally limited in height by conservation concerns, worked as designed, but provided inadequate storage capacity for planned development and was raised twice: between 1907 and 1912 and again between 1929 and 1933. These heightenings still did not meet irrigation demands and in 1946 it was nearly over-topped in an effort to maximize pool elevation. This led to the investigation and construction of the Aswan High Dam 6 kilometres (3.7 mi) upstream. (Full article...)
The Wadi Qattara Dam, also referred to as Gattara or Al-Qattarah, is a clay-fill embankment dam located on Wadi Al-Qattara, 33 km (21 mi) east of Benghazi in Libya. Together with a secondary dam located 10 km (6 mi) downstream at and seven drop structures, the scheme was constructed after floods damaged the Benghazi area in 1938 and 1954. They were also constructed for irrigation water supply. Construction of the dams began in 1968 and was completed in 1971. However, a flood in 1979 severely damaged the main dam and destroyed the secondary dam downstream. The main dam was rehabilitated and the secondary dam was replaced with a rock-fill dam between 2000 and 2004 at a cost of US$30 million. The main dam was heightened 7 m (23 ft) and its total discharge capacity was increased to 240 m3/s (8,476 cu ft/s). Both dams were designed by Coyne et Bellier. (Full article...)
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The Diama Dam, sometimes referred to as the Maka–Diama Dam (French: Barrage de Maka-Diama) is a gravity dam on the Senegal River, spanning the border of Senegal and Mauritania. It is located next to the town of Diama, Senegal and about 22 km (14 mi) north of Saint-Louis, Senegal. The purpose of the dam is to prevent saltwater intrusion upstream, supply water for the irrigation of about 45,000 ha (110,000 acres) of crops and create a road crossing for the road between St. Louis and Nouakchott in Mauritania. Additionally, a ship lock built within the dam provides for navigation upstream. Plans for the dam were first drawn in 1970 when the riparian states within the Senegal River Basin Development Authority agreed to develop the Senegal River. The Diama Dam was to be constructed in conjunction with the Manantali Dam which was to be located further upstream in Mali. Construction on the Diama Dam began on 15 September 1981 and was completed on 12 August 1986. The Manantali Dam was completed in 1988. The Diama project was funded by a US$149.5 million loan from the African Development Bank. The main section of the dam with ship lock and spillway is 170 m (560 ft) long while a 440 m (1,440 ft) long embankment dam section extends north to the edge of the river. A dike further extends the dam to the north. The dam is 18 m (59 ft) tall and its spillway has a maximum discharge of 6,500 m3/s (230,000 cu ft/s).
The small town of Diama is known as a border crossing to and from Mauritania, as the dam is the only land bridge between the two countries. (Full article...)
Dragon: The Bruce Lee Story is a 1993 American biographicaldrama film directed by Rob Cohen. The film stars Jason Scott Lee, with a supporting cast including Lauren Holly, Nancy Kwan, and Robert Wagner. The film follows the life of actor and martial artist Bruce Lee (Jason) from his relocation to the United States from Hong Kong to his career as a martial arts teacher, and then as a television and film actor. It also focuses on the relationship between Bruce and his wife Linda, and the racism to which Bruce was subjected.
The primary source of the screenplay is Cadwell's 1975 biography Bruce Lee: The Man Only I Knew. Other sources include Robert Clouse's book Bruce Lee: The Biography and research by Cohen, including interviews with Cadwell and Bruce's son, Brandon Lee. Rather than a traditional biographical film, Cohen decided to include elements of mysticism and to dramatise fight scenes to give it the same tone as the films in which Bruce starred. Dragon was filmed primarily in Hong Kong, Los Angeles and San Francisco.
Dragon: The Bruce Lee Story received generally positive reviews, with critics typically finding it entertaining despite criticisms of its veneration of Bruce. Jason was widely praised for his performance. The film was a commercial success and its revenue exceeded box office averages for biographical films, which was attributed to its romantic themes and its appeal to people outside the traditional kung fu film audience. A video game adaptation of the same name was released the following year. Dragon is dedicated to Brandon, who died several weeks before its release. (Full article...)
Bruce Lee was a 1994 six-issue comic book miniseries published by Malibu Comics and written by Mike Baron and illustrated by Val Mayerik. It focused on a fictional Bruce Lee character striving his way through gangs and rival dojo owners, while building a movie career. Malibu included a Mortal Kombat short story in the first and fifth issues.
Writer Mike Baron had previously written three issues of the Green Hornet comic published by NOW Comics, about Lee's Kato in the 1966 TV show. Val Mayerik had previously illustrated the second Kato limited series (also published by NOW). Baron states inspiration for the comic came from the 1970s Marvel Comics series Shang-Chi: Master of Kung Fu.
Titan Books collected the miniseries into a trade paperback, simply titled Bruce Lee, in 1995. The publisher Edizioni Star Comics translated the series into Italian for its ongoing series Mortal Kombat & Bruce Lee, published in 1995–1996. (Full article...)
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Bruce Lai, real name Chang Il-do (1950-2014), was a Korean martial artist and actor active in Hong Kong who starred in many Godfrey Ho films.
Also known as Chang Yi-tao, he earned a ninth-degree black belt in tang soo do.
In 2016, Magnetic Press published four issues of Bruce Lee: The Dragon Rises, co-written by Lee's daughter Shannon Lee and Jeff Kline, and illustrated by Brandon McKinney. The fictional story takes places in 2012 with Bruce Lee escaping from a science lab.
In 2018, Magnetic Press/Darby Pop Publishing released the one-shot Bruce Lee: The Walk Of The Dragon, also written by Shannon Lee. (Full article...)
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Brandon Bruce Lee (February 1, 1965 – March 31, 1993) was an American actor. Establishing himself as a rising action star in the early 1990s, he landed what was to be his breakthrough role as Eric Draven in the supernatural superhero film The Crow (1994). However, Lee's career and life were cut short by his accidental death during the film's production.
Transitioning to Hollywood productions, Lee first starred in the Warner Brosbuddy cop film Showdown in Little Tokyo (1991), co-starring Dolph Lundgren. While it did not do well with audiences and critics upon its release, it later became a cult film. This was followed by a leading role in Rapid Fire (1992), produced by 20th Century Fox. Lee, alongside Jeff Imada, is also credited for the fight choreography, which contained elements of Jeet Kune Do. Though the film was not well-received, critics praised Lee's onscreen presence. (Full article...)
The Dragon Lives (Chinese: 詠春大兄; pinyin: Yǒng Chūn Dà Xiōng; Jyutping: wing6 cheun1 daai6 hing1), also known as He's a Legend, He's a Hero, is a 1976 Hong Kong martial arts film starring Bruce Li and directed by Wang Hsing-lei (credited as Singloy Wang). A fictional account of Bruce Lee's life, it is one of numerous films which exploited the popularity of Lee after his death, a practice called Bruceploitation. The film was released in the United States by Film Ventures International on 19 September 1978.
Bruce Lee: The Lost Interview is the name given to the 9 December 1971 edition of The Pierre Berton Show, which featured martial artist/actor Bruce Lee in his only English speaking television interview. Its title is derived from its status; it was presumed lost for several years until its rediscovery and airing on 2 November 1994. Over the course of the interview, which was filmed in Hong Kong, Bruce Lee and Pierre Berton discuss Lee's career, various aspects of martial arts philosophy and the inherent problems faced by an Asian in pursuing stardom in Hollywood. A review of the interview by Bill Stockey said that Bruce Lee's "human side is exposed and he is portrayed as more approachable". (Full article...)
Bruce Le (simplified Chinese: 吕小龙; traditional Chinese: 呂小龍; pinyin: Lǚ Xiǎolóng; born June 5, 1950) is a martial artist and actor known for his martial arts film of the 1970s and 1980s. Most of these were inexpensively produced and were made to capitalise on the martial arts phenomenon started by Bruce Lee, whose death in 1973 left a large box office void (hence the name change to "Bruce Le").
The Legend of Bruce Lee (Chinese: 李小龍傳奇) is a 2008 Chinese biographical television series based on the life story of martial artist and actor Bruce Lee. The 50-episode series was produced and broadcast by CCTV and began airing on October 12, 2008. It was intended to promote Chinese culture alongside the 2008 Beijing Summer Olympics.
It stars Hong Kong actor Danny Chan as Bruce Lee and American actress Michelle Lang as Lee's wife, Linda Lee Cadwell. The production period spanned nine months, with filming taking place in China, Hong Kong, Macau, the United States, Italy, and Thailand, and with a budget of 50 million yuan (US$7.3 million).
Each issue had comics stories featuring these characters, both single-issue stories and multi-issue story arcs. Most issues also included a review of a recent martial arts film. Other issues had interviews with martial arts instructors, while others had interviews with movie or television celebrities related to martial arts.
Early issues had a martial arts instructional section which described some elementary fighting techniques. These were provided by comics illustrator/martial artist Frank McLaughlin. The magazine was in black-and-white except for the cover. The cost of the magazine was 75 cents for issues #1–14. Issue #15 was a Super Annual (all reprints) issue and cost $1.25. Issues #16–33 were $1.00, as well as the 1974 Kung Fu Special (summer 1974); cover-titled Special Album Edition: The Deadly Hands of Kung Fu. Issue #28 (Sept. 1976) was an all-Bruce Lee special, including a 35-page comic book format biography written by Martin Sands, and drawn by Joe Staton and Tony DeZuniga. (Full article...)
Bruce Lee's Fighting Method is a book of volumes covering Bruce Lee's martial arts abilities of the Jeet Kune Do movement. The book is available as a single hardcover volume or a series of four paperback volumes. The text describes Bruce Lee's Kung Fufighting techniques, philosophy and training methods. This book was originally written in 1966 by Bruce Lee. However, Lee decided not to publish this work as he feared that instructors would use the fighting knowledge in this text to promote themselves. In 1978, after Bruce Lee's death, his widow Linda Lee Cadwell decided to make available the information on her husband's work. Lee's death changed the perspective of releasing the information that Bruce Lee himself had vacillated about. The book was published with the help of Mitoshi Uyehara. Uyehara was the founder and owner of Black Belt Magazine. During the early years of the publication, Uyehara served as the publisher. Bruce Lee contributed many articles to the publication during the 1960s and a friendship ensued between the two men. Uyehara, a martial artist in his own right, was a key personage in arranging Lee's material for publication. (Full article...)
Kato is a fictional character from The Green Hornet franchise. This character has appeared with the Green Hornet in radio, film, television, book and comic book versions. Kato is the Green Hornet's crime-fighting sidekick, and Britt Reid's manservant in civilian life, and has been played by a number of actors. On radio, Kato was initially played by Raymond Hayashi, then Roland Parker who had the role for most of the run, and in the later years Mickey Tolan and Paul Carnegie. Keye Luke took the role in the movie serials, and in the television series, he was portrayed by Bruce Lee. Jay Chou played Kato in the 2011 Green Hornet film. (Full article...)
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Game of Death (Chinese: 死亡的遊戲) is an incomplete Hong Kong martial arts film, of which portions were filmed between September and October 1972, and was planned and scheduled to be released by 1973, directed, written, produced by and starring Bruce Lee. The project was paused to film and produce Enter the Dragon. For Game of Death, over 120 minutes of footage was shot. The remaining footage has since been released with Lee's original Cantonese and English dialogue, with John Little dubbing Lee's Hai Tien character as part of the documentary titled Bruce Lee: A Warrior's Journey. Much of the footage that was shot is from what was to be the climax of the film.
During filming, Lee received an offer to star in Enter the Dragon, the first kung fu film to be produced by a Hollywood studio (Warner Bros.), and with a budget unprecedented for the genre ($850,000). Lee died of cerebral edema before the film's release. At the time of his death, he had made plans to resume the filming of The Game of Death. After Lee's death, Enter the Dragon director Robert Clouse was enlisted to finish the film using two stand-ins; it was released in 1978 as Game of Death, five years after Lee's death, by Golden Harvest.
The story of Lee's original 1972 film involves Lee's character, in order to save his younger sister and brother, joining a group of martial artists who are hired to retrieve a stolen Chinese national treasure[need quotation to verify] from the top floor of a five-story pagoda in South Korea, with each floor guarded by martial artists who must be defeated while ascending the tower.[additional citation(s) needed] The 1978 film's plot was altered to a revenge story, where the mafia attempts to kill Lee's character, who fakes his death and seeks vengeance against those who tried to kill him. The final part of the film uses some of Lee's original film footage, but with the pagoda setting changed to a restaurant building, where he fights martial artists hired by the mafia in an attempt to rescue his fiancée Ann Morris (played by Colleen Camp). This revised version received a mixed critical reception but was commercially successful, grossing an estimated US$50,000,000 (equivalent to $230,000,000 in 2023) worldwide. (Full article...)
Jeet Kune Do (Chinese: 截拳道; lit. 'stop fist way or: way of the intercepting fist'; abbreviated JKD) is a hybrid martial art conceived and practiced by martial artist Bruce Lee. It was formed from Lee's experiences in unarmed fighting and self-defense—as well as eclectic, Zen Buddhist and Taoist philosophies—as a new school of martial arts thought.
At the heart of Jeet Kune Do lies the principle of intercepting the opponent's attacks, crafting responses or counterattacks that effectively target the adversary's offensive moves. JKD also incorporates a set of principles to help practitioners make instant decisions and improve the physical and mental self, being intended to have practical applications in life without the traditional routines and metaphysics of conventional martial arts. As an eclectic martial art, it relies on a fighting style heavily influenced by Wing Chun, Tai Chi, taekwondo, boxing, fencing and jujutsu.
Bruce Lee himself never formalized Jeet Kune Do before he died. This forced later JKD practitioners to rely upon their own interpretation of the philosophy created by Bruce Lee. (Full article...)
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Tao of Jeet Kune Do is a book expressing Bruce Lee's martial artsphilosophy and viewpoints, published posthumously (after Bruce Lee's death in 1973). The project for this book began in 1970 when Bruce Lee suffered a back injury during one of his practice sessions. During this time he could not train in martial arts. He was ordered by his doctors to wear a back brace for 6 months in order to recover from his injury. This was a very tiring and dispiriting time for Lee who was always very physically active.
It was during his convalescence that he decided to compile a treatise on the system or approach to martial arts that he was developing; he called it Jeet Kune Do. The bulk of these writings would become the "core set of writings". Many of these writings were done during a single session which provided natural continuity. Lee had also kept various notes throughout the development of his combat philosophy and these would become the disparate notes used in the book. Many of these notes were "sudden inspirations" which were incomplete and lacked any kind of a construct. The combination of the "core set of writings" and the "disparate notes" would be known as the text Tao of Jeet Kune Do.
In 1971, it was Lee's intent to finish the treatise that he started during his convalescence. However, his film career and work prevented him from doing so. He also vacillated about publishing his book as he felt that this work might be used for the wrong purposes. Lee's intent in writing the book was to record one man's way of thinking about the martial arts. It was to be a guidebook, not a set of instructions or "How to" manual to learn martial arts. (Full article...)
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Martial artist and actor Bruce Lee has been subject to extensive media coverage. (Full article...)
The player controls Thomas, a kung fu master, as he fights his way through the five levels of the Devil's Temple to rescue his girlfriend Sylvia from the crime boss Mr. X. As he ascends the tower, he has to fight many enemies along the way and five end-of-level boss battles, a concept inspired by Game of Death. Thomas and each boss have a health meter, and the game temporarily becomes a one-on-one fighting game during boss battles.
The game was a major commercial success, topping the Japanese arcade charts and becoming America's second highest-grossing arcade game of 1985, while receiving critical acclaim for its fast-paced, side-scrolling gameplay and detailed, colorful graphics. A port for the Nintendo Entertainment System (known as the Famicom in Japan) was developed by Nintendo under the direction of Shigeru Miyamoto, released as Spartan X in Japan and Kung Fu in the West, selling 3.5 million copies worldwide. It was also one of the top five best-selling Commodore 64 games of 1986. It spawned the sequel Spartan X 2 (1991) and the spiritual successors Trojan (1986) and Vigilante (1988). (Full article...)
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Wong Shun-leung (Chinese: 黃淳樑; pinyin: Huang Chunliáng; Jyutping: Wong4 Seon4-loeng4; 8 May 1935 – 28 January 1997)[a] was a Hong Kong martial artist who studied Wing Chunkung fu under Yip Man (葉問) and was credited with training Bruce Lee. In interviews, Wong claimed to have won at least 60, and perhaps over 100, street fights against martial artists of various styles, though these numbers cannot be independently confirmed. Due to his reputation, his students and admirers referred to him as 'Gong Sau Wong' (講手王 or 'King of Talking Hands'). Wong recorded one instructional film entitled Wing Chun: The science of in-fighting. (Full article...)
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Leung Siu-lung in 2007
Bruce Liang (28 April 1948) is a Hong Kong martial artist and actor who has appeared in many Hong Kong martial arts movies. He often appeared billed as "Bruce Leung", "Bruce Liang", "Bruce Leong", or "Bruce Leung Siu-lung", and is thus generally grouped among the Bruce Lee clones that sprang up after Lee's death in the subgenre known as Bruceploitation. (Full article...)
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Dragon: The Bruce Lee Story is a 1993 American biographicaldrama film directed by Rob Cohen. The film stars Jason Scott Lee, with a supporting cast including Lauren Holly, Nancy Kwan, and Robert Wagner. The film follows the life of actor and martial artist Bruce Lee (Jason) from his relocation to the United States from Hong Kong to his career as a martial arts teacher, and then as a television and film actor. It also focuses on the relationship between Bruce and his wife Linda, and the racism to which Bruce was subjected.
The primary source of the screenplay is Cadwell's 1975 biography Bruce Lee: The Man Only I Knew. Other sources include Robert Clouse's book Bruce Lee: The Biography and research by Cohen, including interviews with Cadwell and Bruce's son, Brandon Lee. Rather than a traditional biographical film, Cohen decided to include elements of mysticism and to dramatise fight scenes to give it the same tone as the films in which Bruce starred. Dragon was filmed primarily in Hong Kong, Los Angeles and San Francisco.
Dragon: The Bruce Lee Story received generally positive reviews, with critics typically finding it entertaining despite criticisms of its veneration of Bruce. Jason was widely praised for his performance. The film was a commercial success and its revenue exceeded box office averages for biographical films, which was attributed to its romantic themes and its appeal to people outside the traditional kung fu film audience. A video game adaptation of the same name was released the following year. Dragon is dedicated to Brandon, who died several weeks before its release. (Full article...)
Bruce Lee is a platform game written by Ron J. Fortier for Atari 8-bit computers and published in 1984 by Datasoft. The graphics are by Kelly Day and music by John A. Fitzpatrick. The player takes the role of Bruce Lee, while a second player controls either Yamo or alternates with player one for control of Bruce Lee.
Commodore 64 and Apple II versions were released the same year. The game was converted to the ZX Spectrum and Amstrad CPC and published by U.S. Gold. It was the first U.S. Gold release featuring a famous individual. An MSX version was published in 1985 by Comptiq. (Full article...)
The Way of the Dragon was released in Hong Kong on 30 December 1972, and in the United States in August 1974. The film went on to gross an estimated US$130 million worldwide (equivalent to over $700 million adjusted for inflation), against a tight budget of $130,000, earning a thousand times its budget. It was the highest-grossing Hong Kong film up until Lee's next film Enter the Dragon (1973).
The film is primarily set in a restaurant in Rome. The owners are being harassed by a local crime boss, and request help from a relative in Hong Kong. The help arrives in the form of a young martial artist. The conflict between the restaurant staff and the gangsters soon escalates. (Full article...)
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Chen Zhen (陳真; 陈真; Chén Zhēn; Can4 Zan1) is a fictional character created by Hong Kong writer Ni Kuang. First portrayed by Bruce Lee in the 1972 film Fist of Fury, the character has been the subject of numerous film and television series, including remakes and adaptations of Fist of Fury. Many notable actors, including Jet Li and Donnie Yen, have portrayed Chen Zhen on screen after Bruce Lee. Although Chen Zhen's story varies in the different remakes and adaptations, most have an ending similar to the original Fist of Fury. Chen Zhen is believed to be based on Liu Zhensheng (劉振聲), an apprentice of Huo Yuanjia, a martial artist who lived during the late Qing dynasty of China. (Full article...)
The Dragon Lives (Chinese: 詠春大兄; pinyin: Yǒng Chūn Dà Xiōng; Jyutping: wing6 cheun1 daai6 hing1), also known as He's a Legend, He's a Hero, is a 1976 Hong Kong martial arts film starring Bruce Li and directed by Wang Hsing-lei (credited as Singloy Wang). A fictional account of Bruce Lee's life, it is one of numerous films which exploited the popularity of Lee after his death, a practice called Bruceploitation. The film was released in the United States by Film Ventures International on 19 September 1978.
Bruce Lee's Fighting Method is a book of volumes covering Bruce Lee's martial arts abilities of the Jeet Kune Do movement. The book is available as a single hardcover volume or a series of four paperback volumes. The text describes Bruce Lee's Kung Fufighting techniques, philosophy and training methods. This book was originally written in 1966 by Bruce Lee. However, Lee decided not to publish this work as he feared that instructors would use the fighting knowledge in this text to promote themselves. In 1978, after Bruce Lee's death, his widow Linda Lee Cadwell decided to make available the information on her husband's work. Lee's death changed the perspective of releasing the information that Bruce Lee himself had vacillated about. The book was published with the help of Mitoshi Uyehara. Uyehara was the founder and owner of Black Belt Magazine. During the early years of the publication, Uyehara served as the publisher. Bruce Lee contributed many articles to the publication during the 1960s and a friendship ensued between the two men. Uyehara, a martial artist in his own right, was a key personage in arranging Lee's material for publication. (Full article...)
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The Legend of Bruce Lee (Chinese: 李小龍傳奇) is a 2008 Chinese biographical television series based on the life story of martial artist and actor Bruce Lee. The 50-episode series was produced and broadcast by CCTV and began airing on October 12, 2008. It was intended to promote Chinese culture alongside the 2008 Beijing Summer Olympics.
It stars Hong Kong actor Danny Chan as Bruce Lee and American actress Michelle Lang as Lee's wife, Linda Lee Cadwell. The production period spanned nine months, with filming taking place in China, Hong Kong, Macau, the United States, Italy, and Thailand, and with a budget of 50 million yuan (US$7.3 million).
Initially released for Sega platforms, Dragon: The Bruce Lee Story was later ported to the Atari Jaguar and Super Nintendo Entertainment System, each one featuring several changes and additions compared with the original version while both the Game Gear and Master System versions, which were also released in 1994, feature an entirely different gameplay format.
Since its release, Dragon: The Bruce Lee Story garnered mostly negative reviews, with criticism directed at the slow-paced and shallow gameplay. (Full article...)
Outline of underwater diving § Modes of underwater diving
Surface-supplied diver at the Monterey Bay Aquarium, Monterey, California Surface-supplied diving is a mode of underwater diving using equipment supplied with breathing gas through a diver's umbilical from the surface, either from the shore or from a diving support vessel, sometimes indirectly via a diving bell. This is different from scuba diving, where the diver's breathing equipment is completely self-contained and there is no essential link to the surface. The primary advantages of conventional surface supplied diving are lower risk of drowning and considerably larger breathing gas supply than scuba, allowing longer working periods and safer decompression. Disadvantages are the absolute limitation on diver mobility imposed by the length of the umbilical, encumbrance by the umbilical, and high logistical and equipment costs compared with scuba. The disadvantages restrict use of this mode of diving to applications where the diver operates within a small area, which is common in commercial diving work.
Airline, or hookah diving, and "compressor diving" are lower technology variants also using a breathing air supply from the surface. (Full article...)
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Recreational scuba diver Scuba diving is a mode of underwater diving whereby divers use breathing equipment that is completely independent of a surface breathing gas supply, and therefore has a limited but variable endurance. The name scuba is an acronym for "Self-Contained Underwater Breathing Apparatus" and was coined by Christian J. Lambertsen in a patent submitted in 1952. Scuba divers carry their own source of breathing gas, usually compressed air, affording them greater independence and movement than surface-supplied divers, and more time underwater than free divers. Although the use of compressed air is common, a gas blend with a higher oxygen content, known as enriched air or nitrox, has become popular due to the reduced nitrogen intake during long or repetitive dives. Also, breathing gas diluted with helium may be used to reduce the effects of nitrogen narcosis during deeper dives.
Open-circuit scuba systems discharge the breathing gas into the environment as it is exhaled, and consist of one or more diving cylinders containing breathing gas at high pressure which is supplied to the diver at ambient pressure through a diving regulator. They may include additional cylinders for range extension, decompression gas or emergency breathing gas. Closed-circuit or semi-closed circuit rebreather scuba systems allow recycling of exhaled gases. The volume of gas used is reduced compared to that of open-circuit, so a smaller cylinder or cylinders may be used for an equivalent dive duration. Rebreathers extend the time spent underwater compared to open-circuit for the same metabolic gas consumption; they produce fewer bubbles and less noise than open-circuit scuba, which makes them attractive to covert military divers to avoid detection, scientific divers to avoid disturbing marine animals, and media divers to avoid bubble interference.
Scuba diving may be done recreationally or professionally in a number of applications, including scientific, military and public safety roles, but most commercial diving uses surface-supplied diving equipment when this is practicable. Scuba divers engaged in armed forces covert operations may be referred to as frogmen, combat divers or attack swimmers.
Surface-supplied diver at the Monterey Bay Aquarium, Monterey, California Surface-supplied diving is a mode of underwater diving using equipment supplied with breathing gas through a diver's umbilical from the surface, either from the shore or from a diving support vessel, sometimes indirectly via a diving bell. This is different from scuba diving, where the diver's breathing equipment is completely self-contained and there is no essential link to the surface. The primary advantages of conventional surface supplied diving are lower risk of drowning and considerably larger breathing gas supply than scuba, allowing longer working periods and safer decompression. Disadvantages are the absolute limitation on diver mobility imposed by the length of the umbilical, encumbrance by the umbilical, and high logistical and equipment costs compared with scuba. The disadvantages restrict use of this mode of diving to applications where the diver operates within a small area, which is common in commercial diving work.
Airline, or hookah diving, and "compressor diving" are lower technology variants also using a breathing air supply from the surface. (Full article...)
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Surface-supplied diver at the Monterey Bay Aquarium, Monterey, California Surface-supplied diving is a mode of underwater diving using equipment supplied with breathing gas through a diver's umbilical from the surface, either from the shore or from a diving support vessel, sometimes indirectly via a diving bell. This is different from scuba diving, where the diver's breathing equipment is completely self-contained and there is no essential link to the surface. The primary advantages of conventional surface supplied diving are lower risk of drowning and considerably larger breathing gas supply than scuba, allowing longer working periods and safer decompression. Disadvantages are the absolute limitation on diver mobility imposed by the length of the umbilical, encumbrance by the umbilical, and high logistical and equipment costs compared with scuba. The disadvantages restrict use of this mode of diving to applications where the diver operates within a small area, which is common in commercial diving work.
Airline, or hookah diving, and "compressor diving" are lower technology variants also using a breathing air supply from the surface. (Full article...)
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Atmospheric diving suit
An atmospheric diving suit (ADS), or single atmosphere diving suit is a small one-person articulated submersible which resembles a suit of armour, with elaborate pressure joints to allow articulation while maintaining an internal pressure of one atmosphere. An ADS can enable diving at depths of up to 2,300 feet (700 m) for many hours by eliminating the majority of significant physiological dangers associated with deep diving. The occupant of an ADS does not need to decompress, and there is no need for special breathing gas mixtures, so there is little danger of decompression sickness or nitrogen narcosis when the ADS is functioning properly. An ADS can permit less skilled swimmers to complete deep dives, albeit at the expense of dexterity.
Atmospheric diving suits in current use include the Newtsuit, Exosuit, Hardsuit and the WASP, all of which are self-contained hard suits that incorporate propulsion units. The Hardsuit is constructed from cast aluminum (forged aluminum in a version constructed for the US Navy for submarine rescue); the upper hull is made from cast aluminum, while the bottom dome is machined aluminum. The WASP is of glass-reinforced plastic (GRP) body tube construction. (Full article...)
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Recreational scuba diver Scuba diving is a mode of underwater diving whereby divers use breathing equipment that is completely independent of a surface breathing gas supply, and therefore has a limited but variable endurance. The name scuba is an acronym for "Self-Contained Underwater Breathing Apparatus" and was coined by Christian J. Lambertsen in a patent submitted in 1952. Scuba divers carry their own source of breathing gas, usually compressed air, affording them greater independence and movement than surface-supplied divers, and more time underwater than free divers. Although the use of compressed air is common, a gas blend with a higher oxygen content, known as enriched air or nitrox, has become popular due to the reduced nitrogen intake during long or repetitive dives. Also, breathing gas diluted with helium may be used to reduce the effects of nitrogen narcosis during deeper dives.
Open-circuit scuba systems discharge the breathing gas into the environment as it is exhaled, and consist of one or more diving cylinders containing breathing gas at high pressure which is supplied to the diver at ambient pressure through a diving regulator. They may include additional cylinders for range extension, decompression gas or emergency breathing gas. Closed-circuit or semi-closed circuit rebreather scuba systems allow recycling of exhaled gases. The volume of gas used is reduced compared to that of open-circuit, so a smaller cylinder or cylinders may be used for an equivalent dive duration. Rebreathers extend the time spent underwater compared to open-circuit for the same metabolic gas consumption; they produce fewer bubbles and less noise than open-circuit scuba, which makes them attractive to covert military divers to avoid detection, scientific divers to avoid disturbing marine animals, and media divers to avoid bubble interference.
Scuba diving may be done recreationally or professionally in a number of applications, including scientific, military and public safety roles, but most commercial diving uses surface-supplied diving equipment when this is practicable. Scuba divers engaged in armed forces covert operations may be referred to as frogmen, combat divers or attack swimmers.
2nd Reconnaissance Battalion combat diver training with the Dräger LAR V rebreather
Rebreather diving is underwater diving using diving rebreathers, a class of underwater breathing apparatus which recirculate the breathing gas exhaled by the diver after replacing the oxygen used and removing the carbon dioxide metabolic product. Rebreather diving is practiced by recreational, military and scientific divers in applications where it has advantages over open circuit scuba, and surface supply of breathing gas is impracticable. The main advantages of rebreather diving are extended gas endurance, low noise levels, and lack of bubbles.
Rebreathers are generally used for scuba applications, but are also occasionally used for bailout systems for surface-supplied diving. Gas reclaim systems used for deep heliox diving use similar technology to rebreathers, as do saturation divinglife-support systems, but in these applications the gas recycling equipment is not carried by the diver. Atmospheric diving suits also carry rebreather technology to recycle breathing gas as part of the life-support system, but this article covers the procedures of ambient pressure diving using rebreathers carried by the diver.
Rebreathers are generally more complex to use than open circuit scuba, and have more potential points of failure, so acceptably safe use requires a greater level of skill, attention and situational awareness, which is usually derived from understanding the systems, diligent maintenance and overlearning the practical skills of operation and fault recovery. Fault tolerant design can make a rebreather less likely to fail in a way that immediately endangers the user, and reduces the task loading on the diver which in turn may lower the risk of operator error. (Full article...)
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Saturation diver working on the USS Monitor wreck at 70 m (230 ft) depth. Saturation diving is diving for periods long enough to bring all tissues into equilibrium with the partial pressures of the inert components of the breathing gas used. It is a diving mode that reduces the number of decompressions divers working at great depths must undergo by only decompressing divers once at the end of the diving operation, which may last days to weeks, having them remain under pressure for the whole period. A diver breathing pressurized gas accumulates dissolved inert gas used in the breathing mixture to dilute the oxygen to a non-toxic level in the tissues, which can cause potentially fatal decompression sickness ("the bends") if permitted to come out of solution within the body tissues; hence, returning to the surface safely requires lengthy decompression so that the inert gases can be eliminated via the lungs. Once the dissolved gases in a diver's tissues reach the saturation point, however, decompression time does not increase with further exposure, as no more inert gas is accumulated.
Saturation diving takes advantage of this by having divers remain in that saturated state. When not in the water, the divers live in a sealed environment which maintains their pressurised state; this can be an ambient pressure underwater habitat or a saturation system at the surface, with transfer to and from the pressurised living quarters to the equivalent depth underwater via a closed, pressurised diving bell. This may be maintained for up to several weeks, and divers are decompressed to surface pressure only once, at the end of their tour of duty. By limiting the number of decompressions in this way, and using a conservative decompression schedule the risk of decompression sickness is significantly reduced, and the total time spent decompressing is minimised. Saturation divers typically breathe a helium–oxygen mixture to prevent nitrogen narcosis, and limit work of breathing, but at shallow depths saturation diving has been done on nitrox mixtures.
Most of the physiological and medical aspects of diving to the same depths are much the same in saturation and bell-bounce ambient pressure diving, or are less of a problem, but there are medical and psychological effects of living under saturation for extended periods.
Saturation diving is a specialized form of diving; of the 3,300 commercial divers employed in the United States in 2015, 336 were saturation divers. Special training and certification is required, as the activity is inherently hazardous, and a set of standard operating procedures, emergency procedures, and a range of specialised equipment is used to control the risk, that require consistently correct performance by all the members of an extended diving team. The combination of relatively large skilled personnel requirements, complex engineering, and bulky, heavy equipment required to support a saturation diving project make it an expensive diving mode, but it allows direct human intervention at places that would not otherwise be practical, and where it is applied, it is generally more economically viable than other options, if such exist. (Full article...)
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Surface-supplied divers riding a stage to the underwater workplace
Underwater diving, as a human activity, is the practice of descending below the water's surface to interact with the environment. It is also often referred to as diving, an ambiguous term with several possible meanings, depending on context. Immersion in water and exposure to high ambient pressure have physiological effects that limit the depths and duration possible in ambient pressure diving. Humans are not physiologically and anatomically well-adapted to the environmental conditions of diving, and various equipment has been developed to extend the depth and duration of human dives, and allow different types of work to be done.
In ambient pressure diving, the diver is directly exposed to the pressure of the surrounding water. The ambient pressure diver may dive on breath-hold (freediving) or use breathing apparatus for scuba diving or surface-supplied diving, and the saturation diving technique reduces the risk of decompression sickness (DCS) after long-duration deep dives. Atmospheric diving suits (ADS) may be used to isolate the diver from high ambient pressure. Crewed submersibles can extend depth range to full ocean depth, and remotely controlled or robotic machines can reduce risk to humans.
The environment exposes the diver to a wide range of hazards, and though the risks are largely controlled by appropriate diving skills, training, types of equipment and breathing gases used depending on the mode, depth and purpose of diving, it remains a relatively dangerous activity. Professional diving is usually regulated by occupational health and safety legislation, while recreational diving may be entirely unregulated. Diving activities are restricted to maximum depths of about 40 metres (130 ft) for recreational scuba diving, 530 metres (1,740 ft) for commercial saturation diving, and 610 metres (2,000 ft) wearing atmospheric suits. Diving is also restricted to conditions which are not excessively hazardous, though the level of risk acceptable can vary, and fatal incidents may occur.
Recreational diving (sometimes called sport diving or subaquatics) is a popular leisure activity. Technical diving is a form of recreational diving under more challenging conditions. Professional diving (commercial diving, diving for research purposes, or for financial gain) involves working underwater. Public safety diving is the underwater work done by law enforcement, fire rescue, and underwater search and recovery dive teams. Military diving includes combat diving, clearance diving and ships husbandry. Deep sea diving is underwater diving, usually with surface-supplied equipment, and often refers to the use of standard diving dress with the traditional copper helmet. Hard hat diving is any form of diving with a helmet, including the standard copper helmet, and other forms of free-flow and lightweight demand helmets. The history of breath-hold diving goes back at least to classical times, and there is evidence of prehistoric hunting and gathering of seafoods that may have involved underwater swimming. Technical advances allowing the provision of breathing gas to a diver underwater at ambient pressure are recent, and self-contained breathing systems developed at an accelerated rate following the Second World War. (Full article...)
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Surface-supplied diver at the Monterey Bay Aquarium, Monterey, California Surface-supplied diving is a mode of underwater diving using equipment supplied with breathing gas through a diver's umbilical from the surface, either from the shore or from a diving support vessel, sometimes indirectly via a diving bell. This is different from scuba diving, where the diver's breathing equipment is completely self-contained and there is no essential link to the surface. The primary advantages of conventional surface supplied diving are lower risk of drowning and considerably larger breathing gas supply than scuba, allowing longer working periods and safer decompression. Disadvantages are the absolute limitation on diver mobility imposed by the length of the umbilical, encumbrance by the umbilical, and high logistical and equipment costs compared with scuba. The disadvantages restrict use of this mode of diving to applications where the diver operates within a small area, which is common in commercial diving work.
Airline, or hookah diving, and "compressor diving" are lower technology variants also using a breathing air supply from the surface. (Full article...)
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Surface-supplied diver at the Monterey Bay Aquarium, Monterey, California Surface-supplied diving is a mode of underwater diving using equipment supplied with breathing gas through a diver's umbilical from the surface, either from the shore or from a diving support vessel, sometimes indirectly via a diving bell. This is different from scuba diving, where the diver's breathing equipment is completely self-contained and there is no essential link to the surface. The primary advantages of conventional surface supplied diving are lower risk of drowning and considerably larger breathing gas supply than scuba, allowing longer working periods and safer decompression. Disadvantages are the absolute limitation on diver mobility imposed by the length of the umbilical, encumbrance by the umbilical, and high logistical and equipment costs compared with scuba. The disadvantages restrict use of this mode of diving to applications where the diver operates within a small area, which is common in commercial diving work.
Airline, or hookah diving, and "compressor diving" are lower technology variants also using a breathing air supply from the surface. (Full article...)
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Surface-supplied divers riding a stage to the underwater workplace
Underwater diving, as a human activity, is the practice of descending below the water's surface to interact with the environment. It is also often referred to as diving, an ambiguous term with several possible meanings, depending on context. Immersion in water and exposure to high ambient pressure have physiological effects that limit the depths and duration possible in ambient pressure diving. Humans are not physiologically and anatomically well-adapted to the environmental conditions of diving, and various equipment has been developed to extend the depth and duration of human dives, and allow different types of work to be done.
In ambient pressure diving, the diver is directly exposed to the pressure of the surrounding water. The ambient pressure diver may dive on breath-hold (freediving) or use breathing apparatus for scuba diving or surface-supplied diving, and the saturation diving technique reduces the risk of decompression sickness (DCS) after long-duration deep dives. Atmospheric diving suits (ADS) may be used to isolate the diver from high ambient pressure. Crewed submersibles can extend depth range to full ocean depth, and remotely controlled or robotic machines can reduce risk to humans.
The environment exposes the diver to a wide range of hazards, and though the risks are largely controlled by appropriate diving skills, training, types of equipment and breathing gases used depending on the mode, depth and purpose of diving, it remains a relatively dangerous activity. Professional diving is usually regulated by occupational health and safety legislation, while recreational diving may be entirely unregulated. Diving activities are restricted to maximum depths of about 40 metres (130 ft) for recreational scuba diving, 530 metres (1,740 ft) for commercial saturation diving, and 610 metres (2,000 ft) wearing atmospheric suits. Diving is also restricted to conditions which are not excessively hazardous, though the level of risk acceptable can vary, and fatal incidents may occur.
Recreational diving (sometimes called sport diving or subaquatics) is a popular leisure activity. Technical diving is a form of recreational diving under more challenging conditions. Professional diving (commercial diving, diving for research purposes, or for financial gain) involves working underwater. Public safety diving is the underwater work done by law enforcement, fire rescue, and underwater search and recovery dive teams. Military diving includes combat diving, clearance diving and ships husbandry. Deep sea diving is underwater diving, usually with surface-supplied equipment, and often refers to the use of standard diving dress with the traditional copper helmet. Hard hat diving is any form of diving with a helmet, including the standard copper helmet, and other forms of free-flow and lightweight demand helmets. The history of breath-hold diving goes back at least to classical times, and there is evidence of prehistoric hunting and gathering of seafoods that may have involved underwater swimming. Technical advances allowing the provision of breathing gas to a diver underwater at ambient pressure are recent, and self-contained breathing systems developed at an accelerated rate following the Second World War. (Full article...)
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Surface-supplied diver at the Monterey Bay Aquarium, Monterey, California Surface-supplied diving is a mode of underwater diving using equipment supplied with breathing gas through a diver's umbilical from the surface, either from the shore or from a diving support vessel, sometimes indirectly via a diving bell. This is different from scuba diving, where the diver's breathing equipment is completely self-contained and there is no essential link to the surface. The primary advantages of conventional surface supplied diving are lower risk of drowning and considerably larger breathing gas supply than scuba, allowing longer working periods and safer decompression. Disadvantages are the absolute limitation on diver mobility imposed by the length of the umbilical, encumbrance by the umbilical, and high logistical and equipment costs compared with scuba. The disadvantages restrict use of this mode of diving to applications where the diver operates within a small area, which is common in commercial diving work.
Airline, or hookah diving, and "compressor diving" are lower technology variants also using a breathing air supply from the surface. (Full article...)
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A freediver on the ocean floor Freediving, free-diving, free diving, breath-hold diving, or skin diving, is a mode of underwater diving that relies on breath-holding until resurfacing rather than the use of breathing apparatus such as scuba gear.
Besides the limits of breath-hold, immersion in water and exposure to high ambient pressure also have physiological effects that limit the depths and duration possible in freediving.
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