CI's work focuses on science, policy and partnership with businesses, governments and communities. The organization employs nearly 1,000 people and works with more than 2,000 partners in 29 countries. CI has helped support 1,200 protected areas and interventions across 77 countries, protecting more than 6 million square kilometers (2.3 million square miles) of land and sea. (Full article...)
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Bernhard Eduard Fernow (/ˈfɜːrnaʊ/FUR-now; January 7, 1851 – February 6, 1923) was the third chief of the USDA'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...)
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In the 17th century, the buccaneer Alexandre Exquemelin recorded the use of mahogany or Caoba (Cedrela being the Spanish name) on Hispaniola for making canoes: "The Indians make these canoes without the use of any iron instruments, by only burning the trees at the bottom near the root, and afterwards governing the fire with such industry that nothing is burnt more than what they would have..."
The wood first came to the notice of Europeans with the beginning of Spanish colonisation in the Americas. A cross in the Cathedral at Santo Domingo, bearing the date 1514, is said to be mahogany, and Philip II of Spain apparently used the wood for the interior joinery of the palace El Escorial, begun in 1584. However, caoba, as the Taino Natives called the wood, was principally reserved for shipbuilding, and it was declared a royal monopoly at Havana in 1622. Hence very little of the mahogany growing in Spanish controlled territory found its way to Europe.
After the French established a colony in Saint Domingue (now Haiti), some mahogany from that island probably found its way to France, where joiners in the port cities of Saint-Malo, Nantes, La Rochelle and Bordeaux used the wood to a limited extent from about 1700. On the English-controlled islands, especially Jamaica and the Bahamas, mahogany was abundant but not exported in any quantity before 1700. (Full article...)
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Rubber, also called India rubber, latex, Amazonian rubber, caucho, or caoutchouc, as initially produced, consists of polymers of the organic compound isoprene, with minor impurities of other organic compounds. Thailand, Malaysia, Indonesia, and Cambodia are four of the leading rubber producers.
Currently, rubber is harvested mainly in the form of the latex from the Pará rubber tree (Hevea brasiliensis) or others. The latex is a sticky, milky and white colloid drawn off by making incisions in the bark and collecting the fluid in vessels in a process called "tapping". The latex then is refined into the rubber that is ready for commercial processing. In major areas, latex is allowed to coagulate in the collection cup. The coagulated lumps are collected and processed into dry forms for sale.
Natural rubber is used extensively in many applications and products, either alone or in combination with other materials. In most of its useful forms, it has a large stretch ratio and high resilience and also is buoyant and water-proof.
Industrial demand for rubber-like materials began to outstrip natural rubber supplies by the end of the 19th century, leading to the synthesis of synthetic rubber in 1909 by chemical means. [citation needed] (Full article...)
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Sustainability is a social goal for people to co-exist on Earth over a long time. Definitions of this term are disputed and have varied with literature, context, and time. Sustainability usually has three dimensions (or pillars): environmental, economic, and social. Many definitions emphasize the environmental dimension. This can include addressing key environmental problems, including climate change and biodiversity loss. The idea of sustainability can guide decisions at the global, national, and individual levels. A related concept is that of sustainable development, and the terms are often used to mean the same thing. UNESCO distinguishes the two like this: "Sustainability is often thought of as a long-term goal (i.e. a more sustainable world), while sustainable development refers to the many processes and pathways to achieve it."
Details around the economic dimension of sustainability are controversial. Scholars have discussed this under the concept of weak and strong sustainability. For example, there will always be tension between the ideas of "welfare and prosperity for all" and environmental conservation, so trade-offs are necessary. It would be desirable to find ways that separate economic growth from harming the environment. This means using fewer resources per unit of output even while growing the economy. This reduces the environmental impact of economic growth, such as pollution. Doing this is difficult. Some experts say there is no evidence that it is happening at the required scale.
It is necessary to address many barriers to sustainability to achieve a sustainability transition. Some barriers arise from nature and its complexity. Other barriers are extrinsic to the concept of sustainability. For example they can result from the dominant institutional frameworks in countries.
Global issues of sustainability are difficult to tackle as they need global solutions. Existing global organizations such as the UN and WTO are inefficient in enforcing current global regulations. One reason for this is the lack of suitable sanctioning mechanisms. Governments are not the only sources of action for sustainability. For example, business groups have tried to integrate ecological concerns with economic activity. Religious leaders have stressed the need for caring for nature and environmental stability. Individuals can also live in a more sustainable way.
People have criticized the idea of sustainability. One point of criticism is that the concept is vague and only a buzzword. Another is that sustainability might be an impossible goal. Some experts have pointed out that "no country is delivering what its citizens need without transgressing the biophysical planetary boundaries". (Full article...)
The RSPO was established following concerns raised by non-governmental organizations about environmental impacts resulting from palm oil production.
51,999,404 metric tonnes of palm oil produced in 2016 was RSPO certified. Products containing Certified Sustainable Palm Oil (CSPO) can carry the RSPO trademark. Members of the RSPO include palm oil producers, environmental groups, and manufacturers who use palm oil in their products. In 2014, Indonesia accounted for 40% of global palm oil production and 44% of the total RSPO-certified areas.
After the meeting in 2009, a number of environmental organisations were critical of the scope of the agreements reached. Palm oil growers who produce CSPO have been critical of the organization because, though they have met RSPO standards and assumed the costs associated with certification, the market demand for certified palm oil remains low. Even though deforestation has decreased in RSPO-certified oil palm plantations, peatlands continue to be drained and burned for the creation of new RSPO-certified palm plantations. (Full article...)
Natural resource management deals with managing the way in which people and natural landscapes interact. It brings together natural heritage management, land use planning, water management, bio-diversity conservation, and the future sustainability of industries like agriculture, mining, tourism, fisheries and forestry. It recognizes that people and their livelihoods rely on the health and productivity of our landscapes, and their actions as stewards of the land play a critical role in maintaining this health and productivity.
Natural resource management specifically focuses on a scientific and technical understanding of resources and ecology and the Life-supporting capacity of those resources. Environmental management is similar to natural resource management. In academic contexts, the sociology of natural resources is closely related to, but distinct from, natural resource management.
History The emphasis on a sustainability can be traced back to early attempts to understand the ecological nature of North Americanrangelands in the late 19th century, and the resource conservation movement of the same time. This type of analysis coalesced in the 20th century with recognition that preservationist conservation strategies had not been effective in halting the decline of natural resources. A more integrated approach was implemented recognising the intertwined social, cultural, economic and political aspects of resource management. A more holistic, national and even global form evolved, from the Brundtland Commission and the advocacy of sustainable development.
In 2005 the government of New South Wales, Australia established a Standard for Quality Natural Resource Management, to improve the consistency of practice, based on an adaptive management approach.
Avoided Deforestation Partners, or AD Partners, is a non-profit organization under the auspices of the Center for International Policy in Washington, D.C. AD Partners is involved in the global effort to solve climate change by working to end deforestation in tropical rainforest countries. By avoiding the practice of deforestation, i.e., clearing forests to provide inexpensive farmland (also known as “slash and burn agriculture”), the world gains the significant climate benefits of not releasing carbon into the atmosphere. In addition, avoiding deforestation also allows forests to sequester carbon and scrub the air of pollutants. Beyond protecting the Earth's air quality, tropical forests facilitate conditions for rain, replenish water sources, provide habitats for myriad plant and animal species, and sustain the livelihoods of 1.6 billion people globally. Leading scientists and economists say that ending deforestation is the most cost effective and scalable method of reducing greenhouse gases. In fact, they believe that ending deforestation will cut the timeframe for solving the climate crisis in half.
AD Partners’ focus has been and continues to be on advocating for U.S. and international forest protection policies. A large part of their efforts go towards convening global leaders from government, civil society and the business world at the international United National Climate summits, also known as the UNFCCC COP meetings.
Most recently, AD Partners has joined television and movie climate change projects to help raise awareness about the critical link between climate change and the massive deforestation that continues to occur in rainforest countries such as Brazil and Indonesia. For most of the world, the concept that ending deforestation has a direct and profound link to solving the climate crisis is still very much unknown. (Full article...)
An angle gauge is a tool used by foresters to determine which trees to measure when using a variable radius plot design in forest inventory. Using this tool a forester can quickly measure the trees that are in or out of the plot. An angle gauge is similar to a wedge prism though it must be held a fixed distance from the eye to work properly. Unlike the wedge prism, which is held over the plot center, the surveyor's eye is kept over plot-center when using an angle gauge. (Full article...)
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The Global Forest Information Service (GFIS) was an initiative of the Collaborative Partnership on Forests (CPF) and was a collaborative effort of 14 major forest-related international organizations, institutions and convention secretariat, aiming to maximize the value of all forest information resources and providers worldwide through the sharing of forest-related information through a single gateway. The effort was discontinued in 2021. (Full article...)
The practice entails the targeted removal of diseased, damaged, dead, non-productive, structurally unsound, or otherwise unwanted plant material from crop and landscape plants. Some try to remember the categories as "the 4 D's": the last general category being "deranged". In general, the smaller the branch that is cut, the easier it is for a woody plant to compartmentalize the wound and thus limit the potential for pathogen intrusion and decay. It is therefore preferable to make any necessary formative structural pruning cuts to young plants, rather than removing large, poorly placed branches from mature plants.
Specialized pruning practices may be applied to certain plants, such as roses, fruit trees, and grapevines. It is important when pruning that the tree's limbs are kept intact, as this is what helps the tree stay upright. Different pruning techniques may be deployed on herbaceous plants than those used on perennial woody plants. Hedges, by design, are usually (but not exclusively) maintained by hedge trimming, rather than by pruning.
Reasons to prune plants include deadwood removal, shaping (by controlling or redirecting growth), improving or sustaining health, reducing risk from falling branches, preparing nursery specimens for transplanting, and both harvesting and increasing the yield or quality of flowers and fruits. (Full article...)
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The Society of American Foresters was founded on November 30, 1900 by Gifford Pinchot and seven colleagues in the U.S. Department of Agriculture's Division of Forestry. (Full article...)
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Site index is a term used in forestry to describe the potential for foresttrees to grow at a particular location or "site". Site is defined as "The average age of dominate and/or codominate trees of an even-aged, undisturbed site of intolerant trees at a base age"; furthermore, the word site is used in forestry to refer to a distinct area where trees are found. Site index is used to measure the productivity of the site and the management options for that site and reports the height of dominant and co-dominant trees in a stand at a base age such as 25, 50 and 100 years. For example, a red oak with an age of 50 years and a height of 70 feet (21 m) will have a site index of 70. Site index is species specific. Common methods used to determine site index are based on tree height, plant composition and the use of soil maps. (Full article...)
Carbon sequestration is the process of storing carbon in a carbon pool. It plays a crucial role in limiting climate change by reducing the amount of carbon dioxide in the atmosphere. There are two main types of carbon sequestration: biologic (also called biosequestration) and geologic. 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 technologies have been proposed: seaweed farming, 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. (Full article...)
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Forestry is one of the main economic sectors of Chile, representing 14% of the value of the country's total exports. This places the forestry sector in Chile as the second largest export sector behind copper mining. From 1970 to 2005 planted forest surface in Chile grew from 300,000 ha to more than 2.07 million ha. In 2019 Chile had slightly more than 2,3 million ha of forest plantations of which 1,3 million ha were Pinus radiata and 0,9 million ha were of Eucalyptus globulus and Eucalyptus nitens. In 2006 70% of Chile's forestry production went to export, and the industry employed more than 150,000 workers. By 2020 people employed in the sector were down to 112,200.
The wave of forest plantations that begun in the 1970s was initially a response to severe soil erosion that affected much of the country. There was a broad support for plantations when these were first implemented but by the 1980s a conservationist critique had grown exposing the adverse effects of plantations on certain plant and animal species, on biodiversity and on water resources. In many cases the establishment of plantations meant not reforestation but the replacement of existing forests with plantations.
The growth of the forestry sector since the 1980s is the consequence of growth of the export-oriented economy in Chile. Critics argue it has created an enclave economy. In the area of Cañete and Tirúa forestry companies have been accused of contributing to the displacement of indigenous Mapuche communities. In the last decades the communities of Temucuicui have had a conflict, at times physically violent, with the forestry company Forestal Mininco, leading to the detention and imprisonment of community members in the prisons of Angol and Cañete. (Full article...)
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A cant hook or pike or a hooked pike is a traditional logging tool consisting of a wooden lever handle with a movable metal hook called a dog at one end, used for handling and turning logs and cants, especially in sawmills. A cant dog has a blunt end, or possibly small teeth for friction.
A peavey or peavey hook is similar but has a spike in the working end of the handle. Many lumberjacks use the terms interchangeably. A peavey is generally from 30 to 50 inches (0.76 to 1.27 metres) long. The spike is rammed into a log, then a hook (at the end of an arm attached to a pivot a short distance up the handle) grabs the log at a second place. Once engaged, the handle gives the operator leverage to roll or slide or float the log to a new place. The peavey was named for blacksmith Joseph Peavey of Maine who invented the tool as a refinement to the cant hook in the late 1850s. The Peavey Manufacturing Co. is still located in Eddington, Maine, and manufactures several variations. From early times to about 1910, the peavey was written about with various spellings such as "pevy" and "pivie". (Full article...)
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Interception refers to precipitation that does not reach the soil, but is instead intercepted by the leaves, branches of plants and the forest floor. It occurs in the canopy (i.e. canopy interception), and in the forest floor or litter layer (i.e. forest floor interception ). Because of evaporation, interception of liquid water generally leads to loss of that precipitation for the drainage basin, except for cases such as fog interception, but increase flood protection dramatically, Alila et al., (2009). Intercepted snowfall does not result in any notable amount of evaporation, and most of the snow falls off the tree by wind or melts. However, intercepted snow can more easily drift with the wind, out of the watershed. Conifers have a greater interception capacity than hardwoods. Their needles gives them more surface area for droplets to adhere to, and they have foliage in spring and fall, therefore interception also depends on the type of vegetation in a wooded area.
Mitscherlich in 1971 calculated the water storage potential as interception values for different species and stand densities. A storm event might produce 50 – 100 mm of rainfall and 4 mm might be the maximum intercepted in this way. Grah and Wilson in 1944 did sprinkling experiments where they watered plants to see how much of the intercepted is kept after watering stops.
Trees like Norway maple and a small-leaved lime have an interception of approximately 38% of the gross precipitation in temperate climate.
The interception depends on the leaf area index and what kind of leaves they are.
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...)
Sometimes terms which refer to branches of soil science, such as pedology (formation, chemistry, morphology, and classification of soil) and edaphology (how soils interact with living things, especially plants), are used as if synonymous with soil science. The diversity of names associated with this discipline is related to the various associations concerned. Indeed, engineers, agronomists, chemists, geologists, physical geographers, ecologists, biologists, microbiologists, silviculturists, sanitarians, archaeologists, and specialists in regional planning, all contribute to further knowledge of soils and the advancement of the soil sciences.
Paper is a thin sheet material produced by mechanically or chemically processing cellulosefibres derived from wood, rags, grasses, or other vegetable sources in water, draining the water through a fine mesh leaving the fibre evenly distributed on the surface, followed by pressing and drying. Although paper was originally made in single sheets by hand, almost all is now made on large machines—some making reels 10 metres wide, running at 2,000 metres per minute and up to 600,000 tonnes a year. It is a versatile material with many uses, including printing, painting, graphics, signage, design, packaging, decorating, writing, and cleaning. It may also be used as filter paper, wallpaper, book endpaper, conservation paper, laminated worktops, toilet tissue, currency, and security paper, or in a number of industrial and construction processes.
The papermaking process developed in east Asia, probably China, at least as early as 105 CE, by the Han court eunuchCai Lun, although the earliest archaeological fragments of paper derive from the 2nd century BCE in China. The modern pulp and paper industry is global, with China leading its production and the United States following. (Full article...)
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A bucksaw is a hand-poweredframe saw similar to bow saw and generally used with a sawbuck to cut logs or firewood to length (bucking). Modern bucksaws usually have a metal frame ("H" or C-shaped) and a removable blade with coarse teeth held in tension by the frame. Lightweight portable or foldable models used for camping or back-packing are also available. It is often referred to as a bow saw in the North American hardware market, but that term traditionally refers to a different type of saw with a wooden frame. (Full article...)
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Urban forestry is the care and management of single trees and tree populations in urban settings for the purpose of improving the urban environment. Urban forestry involves both planning and management, including the programming of care and maintenance operations of the urban forest. Urban forestry advocates the role of trees as a critical part of the urban infrastructure. Urban foresters plant and maintain trees, support appropriate tree and forest preservation, conduct research and promote the many benefits trees provide. Urban forestry is practiced by municipal and commercial arborists, municipal and utility foresters, environmental policymakers, city planners, consultants, educators, researchers and community activists. (Full article...)
The primary strategy of the Coalition is to bring about the reform of international frameworks, both legal and economic, to correct market failures that result in unsustainable outcomes, and to create economic incentives for the preservation of areas of high biodiversity and endemism worldwide. The Coalition supports the Forests Now Declaration calling for changes in the Kyoto Protocol and other international carbon markets to include land use and forestry.
The Coalition has been instrumental in the establishment of the World Bank's Forest Carbon Partnership Facility and the United Nations' UN-REDD program. Further, based upon these efforts by the Coalition, various industrialized countries (including Norway, the UK, Germany, France, Japan, Australia, Finland, and others) have currently pledged around US$3.0 billion for capacity building and incentives to reduce rates of deforestation in participating developing countries. (Full article...)
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Drywall (also called plasterboard, dry lining, wallboard, sheet rock, gib board, gypsum board, buster board, turtles board, slap board, custard board, and gypsum panel) is a panel made of calcium sulfatedihydrate (gypsum), with or without additives, typically extruded between thick sheets of facer and backer paper, used in the construction of interior walls and ceilings. The plaster is mixed with fiber (typically paper, glass wool, or a combination of these materials); plasticizer, foaming agent; and additives that can reduce mildew, flammability, and water absorption.
In the mid-20th century, drywall construction became prevalent in North America as a time- and labor-saving alternative to lath and plaster. (Full article...)
It is sometimes used as a synonym for particle board, but particle board usually refers to low-density fiberboard. Plywood is not a type of fiberboard, as it is made of thin sheets of wood, not wood fibers or particles. Fiberboard, particularly medium-density fiberboard, is heavily used in the furniture industry. For pieces that will be visible, a veneer of wood is often glued onto fiberboard to give it the appearance of conventional wood.
John EvelynFRS (31 October 1620 – 27 February 1706) was an English writer, landowner, gardener, courtier and minor government official, who is now best known as a diarist. He was a founding Fellow of the Royal Society.
John Evelyn's diary, or memoir, spanned the period of his adult life from 1640, when he was a student, to 1706, the year he died. He did not write daily at all times. The many volumes provide insight into life and events at a time before regular magazines or newspapers were published, making diaries of greater interest to modern historians than such works might have been at later periods. Evelyn's work covers art, culture and politics, including the execution of Charles I, Oliver Cromwell's rise and eventual natural death, the last Great Plague of London, and the Great Fire of London in 1666.
John Evelyn's Diary was first published posthumously in 1818, but over the years was overshadowed by that of Samuel Pepys. Pepys wrote a different kind of diary, in the same era but covering a much shorter period, 1660–1669, and in much greater depth.
Among the many subjects Evelyn wrote about, gardening was an increasing obsession, and he left a huge manuscript on the subject that was not printed until 2001. He published several translations of French gardening books, and his Sylva, or A Discourse of Forest-Trees (1664) was highly influential in its plea to landowners to plant trees, of which he believed the country to be dangerously short. Sections from his main manuscript were added to editions of this, and also published separately. (Full article...)
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Cut-to-length logging (CTL) is a mechanized harvesting system in which trees are delimbed and cut to length directly at the stump. CTL is typically a two-man, two-machine operation with a harvester felling, delimbing, and bucking trees and a forwarder transporting the logs from the felling to a landing area close to a road accessible by trucks. The capital costs for a typical CTL operation, with one harvester and one forwarder, are quite high. The price of a pair of machines alone are approx. US$1,000,000.
Dendrology (Ancient Greek: δένδρον, dendron, "tree"; and Ancient Greek: -λογία, -logia, science of or study of) or xylology (Ancient Greek: ξύλον, ksulon, "wood") is the science and study of woody plants (trees, shrubs, and lianas), specifically, their taxonomic classifications. There is no sharp boundary between plant taxonomy and dendrology; woody plants not only belong to many different plant families, but these families may be made up of both woody and non-woody members. Some families include only a few woody species. Dendrology, as a discipline of industrial forestry, tends to focus on identification of economically useful woody plants and their taxonomic interrelationships. As an academic course of study, dendrology will include all woody plants, native and non-native, that occur in a region. A related discipline is the study of sylvics, which focuses on the autecology of genera and species.
In the past, dendrology included the study of the natural history of woody species in specific regions, but this aspect is now considered part of ecology. The field also plays a role in conserving rare or endangered 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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Robert Marshall (January 2, 1901 – November 11, 1939) was an American forester, writer and wilderness activist who is best remembered as the person who spearheaded the 1935 founding of the Wilderness Society in the United States. Marshall developed a love for the outdoors as a young child. He was an avid hiker and climber who visited the Adirondack Mountains frequently during his youth, ultimately becoming one of the first Adirondack Forty-Sixers. He also traveled to the Brooks Range of the far northern Alaskan wilderness. He wrote numerous articles and books about his travels, including the bestselling 1933 book Arctic Village.
A scientist with a PhD in plant physiology, Marshall became independently wealthy after the death of his father in 1929. He had started his outdoor career in 1925 as forester with the U.S. Forest Service. He used his financial independence for expeditions to Alaska and other wilderness areas. Later he held two significant public appointed posts: chief of forestry in the Bureau of Indian Affairs, from 1933 to 1937, and head of recreation management in the Forest Service, from 1937 to 1939, both during the administration of President Franklin D. Roosevelt. During this period, he directed the promulgation of regulations to preserve large areas of roadless land that were under federal management. Many years after his death, some of those areas were permanently protected from development, exploitation, and mechanization with the passage of the Wilderness Act of 1964.
Defining wilderness as a social as well as an environmental ideal, Marshall promoted organization of a national group dedicated to the preservation of primeval land. In 1935, he was one of the principal founders of The Wilderness Society and personally provided most of the Society's funding in its first years. He also supported socialism and civil liberties throughout his life.
Marshall died of heart failure at the age of 38 in 1939. Twenty-five years later, partly as a result of his efforts, The Wilderness Society helped gain passage of the Wilderness Act. The Act was passed by Congress in 1964 and legally defined wilderness areas of the United States and protected some nine million acres (36,000 km2) of federal land from development, road building and motorized transportation. Today, Marshall is considered largely responsible for the wilderness preservation movement. Several areas and landmarks, including The Bob Marshall Wilderness in Montana and Mount Marshall in the Adirondacks, have been named in his honor. (Full article...)
Rural sociology is a field of sociology traditionally associated with the study of social structure and conflict in rural areas. It is an active academic field in much of the world, originating in the United States in the 1910s with close ties to the national Department of Agriculture and land-grant university colleges of agriculture.
The preindustrial age has been dubbed by Werner Sombart and others as the 'wooden age', as timber and firewood were the basic resources for energy, construction and housing. The development of modern forestry is closely connected with the rise of capitalism, the economy as a science and varying notions of land use and property. Roman Latifundiae, large agricultural estates, were quite successful in maintaining the large supply of wood that was necessary for the Roman Empire. Large deforestations came with the decline of the Romans. However already in the 5th century, monks in the then Byzantine Romagna on the Adriatic coast, were able to establish stone pine plantations to provide fuelwood and food. This was the beginning of the massive forest mentioned by Dante Alighieri in his 1308 poem Divine Comedy.
Similar sustainable formal forestry practices were developed by the Visigoths in the 7th century when, faced with the ever-increasing shortage of wood, they instituted a code concerned with the preservation of oak and pine forests. The use and management of many forest resources has a long history in China as well, dating back to the Han dynasty and taking place under the landowning gentry. A similar approach was used in Japan. It was also later written about by the Ming dynasty Chinese scholar Xu Guangqi (1562–1633).
In Europe, land usage rights in medieval and early modern times allowed different users to access forests and pastures. Plant litter and resin extraction were important, as pitch (resin) was essential for the caulking of ships, falking and hunting rights, firewood and building, timber gathering in wood pastures, and grazing animals in forests. The notion of "commons" (German "Allmende") refers to the underlying traditional legal term of common land. The idea of enclosed private property came about during modern times. However, most hunting rights were retained by members of the nobility which preserved the right of the nobility to access and use common land for recreation, like fox hunting. (Full article...)
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Pacing is a reasonably easy and quick method of measuring distance in the field. It is used to measure a distance and is often used with a sighting or a hand compass. Most commonly, pacing is split up into segments, such as chains, which are set measures of distance. By determining one's own pace, distance can easily be estimated. (Full article...)
Ecological restoration, or ecosystem restoration, is the process of assisting the recovery of an ecosystem that has been degraded, damaged, or destroyed. It is distinct from conservation in that it attempts to retroactively repair already damaged ecosystems rather than take preventative measures. Ecological restoration can reverse biodiversity loss, combat climate change, and support local economies. Habitat restoration involves the deliberate rehabilitation of a specific area to reestablish a functional ecosystem. To achieve successful habitat restoration, it's essential to understand the life cycles and interactions of species, as well as the essential elements such as food, water, nutrients, space, and shelter needed to support species populations. When it's not feasible to restore habitats to their original size or state, designated areas known as wildlife corridors can be established. These corridors connect different habitats and open spaces, facilitating the survival of species within human-dominated landscapes. For instance, marshes serve as critical stopover sites for migratory birds, wildlife overpasses enable animals to safely cross over highways, and protected riparian zones within urban settings provide necessary refuges for flora and fauna. The United Nations named 2021-2030 the Decade on Ecosystem Restoration.
Scientists estimate that the current species extinction rate, or the rate of the Holocene extinction, is 1,000 to 10,000 times higher than the normal, background rate. Habitat loss is a leading cause of species extinctions and ecosystem service decline.
Two methods have been identified to slow the rate of species extinction and ecosystem service decline: conservation of quality habitat and restoration of degraded habitat. The number and size of ecological restoration projects have increased exponentially in recent years.
Restoration goals reflect political choices, and restoration goals differ by place and culture. (Full article...)
In this veneering process, large sheets of veneer are produced on a machine similar to a lathe. These are dyed, spread with suitable adhesives, and then compressed and bonded into thick (typically 70 cm) logs, which are then sliced to create the end product. If the sheets are compressed between platens with an undulating surface, the slice will cross several layers to produce a patterned effect. Many different designs can be obtained by varying the platens, the dyes and the stacking order.
Although the product may be considered sustainable, multilaminar veneer does have a relatively high carbon footprint due to the numerous dyeing, laminating, pressing, and slicing operations. (Full article...)
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A yarder is piece of logging equipment that uses a system of cables to pull or fly logs from the stump to a collection point. It generally consists of an engine, drums, and spar, but has a range of configurations and variations, such as the swing yarder. (Full article...)
Its 48 endorsed national forest certification systems represent more than 280 million hectares (690×10^6 acres) of certified forests. This makes it the largest forest certification system in the world, covering about two-thirds of the globally certified forest area. It is based in Geneva, Switzerland. (Full article...)
It was re-established in 2018 after previously existing from 1919 to 1987. (Full article...)
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Selective logging or partial forest removal is the practice of cutting down a few species of trees while leaving the rest intact and unharmed. Selective logging is often considered a better alternative to clear cutting. Selective logging in the Brazilian Amazon Rainforest was recently shown in analyses of Landsat Enhanced Thematic Mapper Plus data at high spatial resolution to be occurring at rates of about 12,000–20,000 km2 per year, thus indicating the central role of selective logging in tropical forest disturbance. Although selective logging has far less impact on forest processes than deforestation, selectively logged sites have higher rates of forest fires, tree fall, changes in microclimate, soil compaction and erosion, among other ecological impacts on biodiversity and ecosystem functioning.
Selective logging is a dominant form of land use in the Brazilian Amazon. Canopy gap fractions patterns are found to result from selective logging caused tree falls, roads, skid trails, and log decks, which are areas where logs are staged for transport. These gaps can vary between logging operations. Logging activities has now increased from initially low volume harvests of floodplains to much higher rates that remove around 25 million cubic metres (880×10^6 cu ft) of wood from the forest each year. The ecological, social, and economic impacts drive a better understanding of efficient forest management techniques and deforestation. (Full article...)
Scyliorhinus meadi, the blotched catshark, is a little-known species of catshark, and part of the family Scyliorhinidae, found in the western central Atlantic Ocean. It inhabits banks of deep-sea coral at depths of 329–548 m (1,079–1,798 ft), feeding on cephalopods, shrimp, and bony fishes. This species can be identified by its wide body and head, and the dark saddle-like markings on its back. It also has small spots that fluoresce yellow under a blue light. Adult blotched catsharks have not been observed; the largest immature specimen is 49 cm (19 in) long. Like other catsharks, it is believed to be oviparous. This species is not dangerous to humans and has no commercial significance. (Full article...)
The blacktip reef shark (Carcharhinus melanopterus) is a species of requiem shark, in the family Carcharhinidae, which can be easily identified by the prominent black tips on its fins (especially on the first dorsal fin and its caudal fin). Among the most abundant sharks inhabiting the tropicalcoral reefs of the Indian and Pacific Oceans, this species prefers shallow, inshore waters. Its exposed first dorsal fin is a common sight in the region. The blacktip reef shark is usually found over reef ledges and sandy flats, though it has also been known to enter brackish and freshwater environments. It typically attains a length of 1.6 m (5.2 ft). Like other sharks, the females are larger than the males.
The blacktip reef shark has extremely small home ranges and exhibits strong site fidelity, remaining within the same local area for up to several years at a time. It is an active predator of small bony fish, cephalopods, and crustaceans, and has also been known to feed on sea snakes and seabirds. Accounts of the blacktip reef shark's life history have been variable and sometimes contradictory, in part reflecting geographical differences within the species. Like other members of its family, this shark is viviparous, with females giving birth to two to five young on a biennial, annual, or possibly biannual cycle. Reports of the gestation period range from 7–9, through 10–11, to possibly 16 months. Mating is preceded by the male following closely behind the female, likely attracted by her chemical signals. Newborn sharks are found further inshore and in shallower water than adults, frequently roaming in large groups over areas flooded by high tide.
Timid and skittish, the blacktip reef shark is difficult to approach and seldom poses a danger to humans unless roused by food. However, people wading through shallow water are at risk of having their legs mistakenly bitten. This shark is used for its meat, fins, and liver oil, but is not considered to be a commercially significant species. The International Union for Conservation of Nature has assessed the blacktip reef shark as Vulnerable. Although the species as a whole remains widespread and relatively common, overfishing of this slow-reproducing shark has led to its decline at a number of locales. (Full article...)
Squalus crassispinus is a rare, small and slender dogfish with a broad head and short snout. There is a broad, small medial barbel on the anterior nasal flaps. The pectoral fin has a shallowly concave posterior margin. The first dorsal fin is moderately high, and both dorsal fin spines are very stout.
Coloration is light grey above, paler below, with no white spots. The pale dorsal fins have dusky tips.
The speartooth shark (Glyphis glyphis) is a rare species of river shark, belonging to the familyCarcharhinidae. It inhabits coastal marine waters and tidal reaches of large tropical rivers in northern Australia and New Guinea. Despite being a member of the river shark genus, it is also found in near-shore marine waters, favoring highly turbid environments over a wide range of salinities. This robustly built, gray-colored shark is characterized by a short and broad snout, tiny eyes, a relatively large second dorsal fin, and a black blotch beneath each pectoral fin near the tip. Another identifying trait is its teeth, which are large, triangular, and serrated in the upper jaw and narrow, spear-like, and serrated only near the tips in the lower jaw. Adults grow to about 2.6 m (8.5 ft) long.
The daggernose shark (Isogomphodon oxyrhynchus) is a little-known species of requiem shark, in the familyCarcharhinidae, and the only extant member of its genus. It inhabits shallow tropical waters off northeastern South America, from Trinidad to northern Brazil, favoring muddy habitats such as mangroves, estuaries, and river mouths, though it is intolerant of fresh water. A relatively small shark typically reaching 1.5 m (4.9 ft) in length, the daggernose shark is unmistakable for its elongated, flattened, and pointed snout, tiny eyes, and large paddle-shaped pectoral fins.
Daggernose sharks are predators of small schooling fishes. Its reproduction is viviparous, with females give birth to 2–8 pups every other year during the rainy season; this species is capable of shifting the timing of its reproductive cycle by several months in response to the environment. Harmless to humans, the daggernose shark is caught for food and as bycatch in artisanal and commercial fisheries. Limited in range and slow-reproducing, it has been assessed as Critically Endangered by International Union for Conservation of Nature in light of a steep population decline in recent years. The current population is believed to be extremely low, with no more than 250 individuals believed to be in existence as of 2023. Indeed, it may even be in reproductive collapse, in which case it will likely become extinct in the near future. (Full article...)
This family of sharks is named in honour of Kakichi Mitsukuri who brought the holotype of the only species in this family to David Starr Jordan to be scientifically described.
The most distinctive characteristic of the goblin sharks is the long, trowel-shaped, beak-like snout, much longer than those of other sharks. Its long snout is covered with ampullae of Lorenzini that enable it to sense minute electric fields produced by nearby prey, which it can snatch up by rapidly extending its jaws. They also possess long, protrusible jaws. When the jaws are retracted, the shark resembles a sand tiger shark, Carcharias taurus, with an unusually long nose. Its nose resembles the nose of a goblin, which is how it received its name. These sharks have only been seen about 50 times since their discovery in 1897. (Full article...)
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The silvertip shark (Carcharhinus albimarginatus) is a large species of requiem shark, in the familyCarcharhinidae, with a fragmented distribution throughout the tropicalIndian and Pacific Oceans. It is often encountered around offshore islands and coral reefs, and has been known to dive to a depth of 800 m (2,600 ft). The silvertip shark resembles a larger and bulkier grey reef shark (C. amblyrhynchos), but can be easily identified by the prominent white margins on its fins. It attains a maximum length of 3 m (10 ft).
An aggressive, powerful apex predator, the silvertip shark feeds on a wide variety of bony fishes, as well as eagle rays, smaller sharks, and cephalopods. This species dominates other requiem sharks of equal size when competing for food, and larger individuals are often heavily scarred from conflicts with others of its species. As with other members of its family, the silvertip shark is viviparous, with females giving birth to one to 11 pups in the summer. Silvertip sharks are regarded as potentially dangerous to humans, as they often approach divers quite closely. This slow-reproducing species is taken by commercial fisheries for its meat, fins, skin, cartilage, and jaws and teeth, which has apparently led to local population declines or extirpations. (Full article...)
The northern spiny dogfish (Squalus griffini), also known as the brown dogfish, grey spiny dogfish or Griffin's dogfish, is a marine species of the familySqualidae, found off New Zealand's North Island. The length of the longest specimen measured is 89.9 cm (35.4 in).
The Burmese bamboo shark, Chiloscyllium burmensis, is an extremely rare bamboo shark in the familyHemiscylliidae. The first specimen was caught in 1963 off the coast from Rangoon in Myanmar (known as Burma at the time) in a depth of 29 – 33 m. This holotype is an adult male, 57 cm long and kept in the National Museum of Natural History, Smithsonian Institution, Washington DC. Later, three more specimens, two males and one female, were recorded in 2018 from the Bangladesh Fisheries Development Corporation Fish Landing Center of Cox’s Bazar. (Full article...)
The frilled shark (Chlamydoselachus anguineus), also known as the lizard shark, is one of the two extant species of shark in the familyChlamydoselachidae (the other is the southern African frilled shark (Chlamydoselachus africana)). The frilled shark is considered a living fossil, because of its primitive, anguilliform (eel-like) physical traits, such as a dark-brown color, amphistyly (the articulation of the jaws to the cranium), and a 2.0 m (6.6 ft)–long body, which has dorsal, pelvic, and anal fins located towards the tail. The common name, frilled shark, derives from the fringed appearance of the six pairs of gill slits at the shark's throat.
The two species of frilled shark are distributed throughout regions of the Atlantic and the Pacific oceans, usually in the waters of the outer continental shelf and of the upper continental slope, where the sharks usually live near the ocean floor, near biologically productive areas of the ecosystem. To live on a diet of cephalopods, smaller sharks, and bony fish, the frilled shark practices diel vertical migration to feed at night at the surface of the ocean. When hunting food, the frilled shark curls its tail against a rock and moves like an eel, bending and lunging to capture and swallow whole prey with its long and flexible jaws, which are equipped with 300 recurved, needle-like teeth.
Reproductively, the two species of frilled shark, C. anguineus and C. africana, are aplacental viviparous animals, born of an egg, without a placenta to the mother shark. Contained within egg capsules, the shark embryos develop in the body of the mother shark; at birth, the infant sharks emerge from their egg capsules in the uterus, where they feed on yolk. Although it has no distinct breeding season, the gestation period of the frilled shark can be up to 3.5 years long, to produce a litter of 2–15 shark pups. Usually caught as bycatch in commercial fishing, the frilled shark has some economic value as a meat and as fishmeal; and has been caught from depths of 1,570 m (5,150 ft), although its occurrence is uncommon below 1,200 m (3,900 ft); whereas in Suruga Bay, Japan, the frilled shark commonly occurs at depths of 50–200 m (160–660 ft). (Full article...)
Orectolobus reticulatus, the network wobbegong, is a recently described species of carpet shark found in relatively shallow waters off Kimberley and Darwin in north-western Australia. With a known maximum length of only 52.3 centimetres (20.6 in), it may be the smallest species of wobbegong. Until its description in 2008, it had been confused with the northern wobbegong. The network wobbegong has a short snout, broad head, elongated body, and two dorsal fins, with the first being slightly larger than the second. Its body is grayish brown with darker brown markings and a pale yellow underbelly. The network wobbegong lives in shallow waters along reefy bottoms.
The reproductive strategies of this species are not known, but other Orectolobus species are oviparous and have slow reproductive cycles. Its dentition indicates that the diet of the network wobbegong consists predominantly of small fishes, as well as some cephalopods and crustaceans, such as lobsters and crabs. (Full article...)
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The hardnose shark (Carcharhinus macloti) is a species of requiem shark, in the family Carcharhinidae, so named because of the heavily calcifiedcartilages in its snout. A small bronze-coloured shark reaching a length of 1.1 m (3.6 ft), it has a slender body and a long, pointed snout. Its two modestly sized dorsal fins have distinctively elongated rear tips. The hardnose shark is widely distributed in the western Indo-Pacific, from Kenya to southern China and northern Australia. It inhabits warm, shallow waters close to shore.
The lizard catshark (Schroederichthys saurisqualus) is a small shark species of the catsharkfamily, Scyliorhinidae, found off the coast of southern Brazil on the upper continental shelf at depths of between 250 and 500 metres (820 and 1,640 ft). (Full article...)
The families in the order Carcharhiniformes are expected to be revised; recent DNA studies show that some of the conventional groups are not monophyletic.
The oldest members of the order appeared during the Middle-Late Jurassic, which have teeth and body forms that are morphologically similar to living catsharks. Carchariniformes first underwent major diversification during the Late Cretaceous, initially as mostly small-sized forms, before radiating into medium and large body sizes during the Cenozoic. (Full article...)
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The blacktip shark (Carcharhinus limbatus) is a species of requiem shark, and part of the family Carcharhinidae. It is common to coastal tropical and subtropical waters around the world, including brackish habitats. Genetic analyses have revealed substantial variation within this species, with populations from the western Atlantic Ocean isolated and distinct from those in the rest of its range. The blacktip shark has a stout, fusiform body with a pointed snout, long gill slits, and no ridge between the dorsal fins. Most individuals have black tips or edges on the pectoral, dorsal, pelvic, and caudal fins. It usually attains a length of 1.5 m (4.9 ft).
Swift, energetic piscivores, blacktip sharks are known to make spinning leaps out of the water while attacking schools of small fish. Their demeanor has been described as "timid" compared to other large requiem sharks. Both juveniles and adults form groups of varying size. Like other members of its family, the blacktip shark is viviparous; females bear one to 10 pups every other year. Young blacktip sharks spend the first months of their lives in shallow nurseries, and grown females return to the nurseries where they were born to give birth themselves. In the absence of males, females are also capable of asexual reproduction.
Normally wary of humans, blacktip sharks can become aggressive in the presence of food and have been responsible for a number of attacks on people. This species is of importance to both commercial and recreational fisheries across many parts of its range, with its meat, skin, fins, and liver oil used. It has been assessed as Vulnerable by the IUCN, on the basis of its low reproductive rate and high value to fishers. (Full article...)
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The silky shark (Carcharhinus falciformis), also known by numerous names such as blackspot shark, gray whaler shark, olive shark, ridgeback shark, sickle shark, sickle-shaped shark and sickle silk shark, is a species of requiem shark, in the familyCarcharhinidae, named for the smooth texture of its skin. It is one of the most abundant sharks in the pelagic zone, and can be found around the world in tropical waters. Highly mobile and migratory, this shark is most often found over the edge of the continental shelf down to 50 m (164 ft). The silky shark has a slender, streamlined body and typically grows to a length of 2.5 m (8 ft 2 in). It can be distinguished from other large requiem sharks by its relatively small first dorsal fin with a curving rear margin, its tiny second dorsal fin with a long free rear tip, and its long, sickle-shaped pectoral fins. It is a deep, metallic bronze-gray above and white below.
With prey often scarce in its oceanic environment, the silky shark is a swift, inquisitive, and persistent hunter. It feeds mainly on bony fishes and cephalopods, and has been known to drive them into compacted schools before launching open-mouthed, slashing attacks. This species often trails schools of tuna, a favored prey. Its sense of hearing is extremely acute, allowing it to localize the low-frequency noises generated by other feeding animals, and, by extension, sources of food. The silky shark is viviparous, meaning that the developing embryos are sustained by a placental connection to their mother. Significant geographical variation is seen in its life history details. Reproduction occurs year-round except in the Gulf of Mexico, where it follows a seasonal cycle. Females give birth to litters of up to 16 pups annually or biennially. The newborn sharks spend their first months in relatively sheltered reef nurseries on the outer continental shelf, growing substantially before moving into the open ocean.
The large size and cutting teeth of the silky shark make it potentially dangerous, and it has behaved aggressively towards divers. However, attacks are rare, as few humans enter its oceanic habitat. Silky sharks are valued for their fins, and to a lesser extent their meat, hide, liver oil, and jaws. Because of their abundance, they form a major component of commercial and artisanal shark fisheries in many countries. Furthermore, their association with tuna results in many sharks being taken as bycatch in tuna fisheries. Although slow-reproducing like most other sharks, the wide distribution and large population size of the silky shark was once thought to buffer the species against these fishing pressures. However, data now suggest that silky shark numbers are declining around the world, which prompted the IUCN to reassess its conservation status to Vulnerable in 2017. (Full article...)
The brown lanternshark or bristled lanternshark (Etmopterus unicolor) is a little-known species of deep-sea dogfish shark in the family Etmopteridae. It is found off Japan and New Zealand, and possibly also South Africa and Australia, typically deeper than 300 m (980 ft). This species can be distinguished from other lanternsharks by its coloration, which is a uniform dark gray or brown without the ventral surface being much darker and clearly delineated from the rest of the body. The brown lanternshark feeds on small bony fishes, cephalopods, and crustaceans. Reproduction is ovoviviparous, with females giving birth to 9–18 young. An unusually high proportion of individuals in Suruga Bay are hermaphrodites, with both male and female characteristics. (Full article...)
The rough longnose shark (Deania hystricosa) is a little-known deepwater dogfish. This species was described by Samuel Garman in 1906 and originally named Acanthidium hystricosa.
The rough longnose dogfish has an extremely long snout, no anal fin, small grooved dorsal spines, and rough, pitchfork-shaped dermal denticles. The first dorsal fin is long and narrow.
Maximum length is 109 cm. Found in the Eastern Atlantic around Madeira and in the western Pacific around southern Japan, this shark is rarely seen, but lives between 600 and 1,000 m. It is ovoviviparous with probably around 12 pups per litter.
The Atlantic sawtail catshark (Galeus atlanticus) is a little-known species of catshark, part of the familyScyliorhinidae, found in a small area of the northeastern Atlantic Ocean, centered on the Strait of Gibraltar and the Alborán Sea. It is found on or close to the bottom over the continental slope, mostly at depths of 400–600 m (1,300–2,000 ft). This shark closely resembles, and was once thought to be the same species as, the blackmouth catshark (G. melastomus); both are slender with a series of dark saddles and blotches along the back and tail, and a prominent crest of enlarged dermal denticles along the dorsal edge of the caudal fin. It differs subtly from G. melastomus in characters including snout length, caudal peduncle depth, and the color of the furrows at the corner of its mouth.
The filetail catshark (Parmaturus xaniurus) is an Eastern Pacific endemic deepwater catshark ranging from Oregon to the Gulf of California. Adults are epibenthic and found near areas of rocky vertical relief over soft mud bottoms on the outer continental shelf and upper slope at depths of 91 to 1,251 m, juveniles are mesopelagic, found around 500 m off the bottom in waters over 1,000 m deep. They have been seen at the Lasuen Knoll during ROV expeditions at roughly 300 m deep. Reaches a maximum size of 60 cm TL. An oviparous species, females deposit eggcases throughout the year with concentrated reproductive output July through September. There is no information available on the age and growth, longevity, fecundity, abundance or mortality of this species. It is not targeted by commercial fisheries or utilized for human consumption, but is known to be incidental catch in longline and bottom trawl fisheries, although no specific data is available. (Full article...)
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The redspotted catshark (Schroederichthys chilensis), also known as the Chilean catshark, is a species of catshark commonly found in the coastal waters of the southeastern Pacific, from central Peru to southern Chile. They are typically found in the rocky sublittoral areas at the edge of the continental shelf, in waters down to 100 m in depth. They spend the spring, summer, and fall in rocky subtidal areas, but winter in deeper offshore waters due to the strong currents at that time of year. (Full article...)
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The pocket shark (Mollisquama parini) is a species of kitefin shark in the familyDalatiidae. The species is found in deep water off Chile in the southeastern Pacific Ocean. It was the only member of the genusMollisquama, until another species, M. mississippiensis, was discovered in the Gulf of Mexico. Both species are distinguished from other sharks by two pockets next to the front fins. The pockets are large, measuring about 4% of the shark's body length. Some researchers hypothesize that the pockets may excrete some kind of glowing fluid or pheromones. (Full article...)
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The rasptooth dogfish (Etmopterus sheikoi) is a dogfish, found on the Kyushu–Palau Ridge in the northwest Pacific Ocean at depths of 360 m. Its maximum length is unknown. This species was originally described as Centroscyllium sheikoi, and subsequently allocated to the newly named genus Miroscyllium based on anatomical features not shared with other Centroscyllium. More recent molecular data suggest this species belongs to the genus Etmopterus, but as of June 2014 Miroscyllium sheikoi remains the valid name recognized by FishBase, the Catalog of FishesWorld Register of Marine Species, and the IUCN
;Extinct Miroscyllium The genus name Miroscyllium was proposed in 1990 to encompass a single living species (now E. sheikoi) and in 2006 was expanded to include fossil teeth of an extinct species (originally described as "?Centroscyllium sp." in 1972) recovered from the Miocene (23.03–5.332 Ma) strata in Vaucluse, southwestern France. The teeth of Miroscyllium (sensu lato) are similar to those of Etmopterus, but differ in having multiple cusps on the tooth crowns ("multicuspidate crowns"). (Full article...)
The white ghost catshark (Apristurus aphyodes) is a shark of the catshark familyScyliorhinidae found in deep water in the northeast Atlantic between latitudes57°N and 58°N. A deep-water catshark known from the eastern North Atlantic from depths of 1,014 to 1,800 m, it is known from only a limited number of specimens. It reaches a maximum of 54 cm or 1.7 ft total length which is a medium size for the Apristurus genus. (Full article...)
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The grey reef shark or gray reef shark (Carcharhinus amblyrhynchos, sometimes misspelled amblyrhynchus or amblyrhinchos) is a species of requiem shark, in the familyCarcharhinidae. One of the most common reef sharks in the Indo-Pacific, it is found as far east as Easter Island and as far west as South Africa. This species is most often seen in shallow water near the drop-offs of coral reefs. It has the typical "reef shark" shape, with a broad, round snout and large eyes. It can be distinguished from similar species by the plain or white-tipped first dorsal fin, the dark tips on the other fins, the broad, black rear margin on the tail fin, and the lack of a ridge between the dorsal fins. Most individuals are less than 1.88 m (6.2 ft) long.
The grey reef shark is a fast-swimming, agile predator that feeds primarily on free-swimming bony fishes and cephalopods. Its aggressive demeanor enables it to dominate many other shark species on the reef, despite its moderate size. Many grey reef sharks have a home range on a specific area of the reef, to which they continually return. However, they are social rather than territorial. During the day, these sharks often form groups of five to 20 individuals near coral reef drop-offs, splitting up in the evening as the sharks begin to hunt. Adult females also form groups in very shallow water, where the higher water temperature may accelerate their growth or that of their unborn young. Like other members of its family, the grey reef shark is viviparous, meaning the mother nourishes her embryos through a placental connection. Litters of one to six pups are born every other year.
The grey reef shark was the first shark species known to perform a threat display, a stereotypical behavior warning that it is prepared to attack. The display involves a "hunched" posture with characteristically dropped pectoral fins, and an exaggerated, side-to-side swimming motion. Grey reef sharks often do so if they are followed or cornered by divers to indicate they perceive a threat. This species has been responsible for a number of attacks on humans, and should be treated with caution, especially if it begins to display. It has been caught in many fisheries and is susceptible to local population depletion due to its low reproduction rate and limited dispersal. As a result, the International Union for Conservation of Nature has assessed this species as endangered. (Full article...)
The creek whaler (Carcharhinus fitzroyensis) is a common species of requiem shark, and part of the family Carcharhinidae, endemic to northern Australia. It frequents shallow waters close to shore, including estuaries. This small, stocky shark usually grows to 1.0–1.3 m (3.3–4.3 ft) long and is brownish in color without conspicuous fin markings. It can be identified by its long snout, large, triangular pectoral fins, and large, anteriorly positioned first dorsal fin.
The diet of the creek whaler consists mainly of small teleost fishes and crustaceans. It is viviparous, with the unborn young being sustained through a placental connection. The defined mating season lasts from May to July. Females give birth to one to seven pups annually, following a gestation period of seven to 9 months. A small number of creek whalers are caught incidentally in inshoregillnets and used for food, but the effect of fishing on its population seems to be inconsequential. As a result, the IUCN has listed this species under Least Concern. (Full article...)
The bluegrey carpetshark (Brachaelurus colcloughi) or Colclough's shark, is an uncommon species of carpet sharkendemic to shallow inshore waters off northeastern Australia. It is one of the two extant members of the familyBrachaeluridae. The bluegrey carpetshark has a stocky body with a wide, slightly flattened head, dorsally placed eyes, and a pair of long barbels with posterior skin flaps. It has large pectoral fins, two dorsal fins of unequal size placed far back on the body, and a sizeable space between the anal fin and the base of the caudal fin. Growing to 76 cm (30 in) long, this species has a black-and-white colour pattern as a juvenile, which largely fades with age such as that adults are brownish.
The black roughscale catshark (Apristurus melanoasper) is a catshark of the family Scyliorhinidae. It is recorded from the north Atlantic, eastern South Atlantic, in the Indian Ocean and around Australia and New Zealand. The species can be found on continental shelf at depths between 510 and 1,520 m. It can grow up to 90 cm (35 in). (Full article...)
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The gulf catshark (Asymbolus vincenti) is a species of catshark, found only off the shores of southern Australia at depths between 27 and 650 metres (89 and 2,133 ft). This species can reach a length of 61 centimetres (24 in) TL. (Full article...)
Catsharks of this genus have a slim body and variegated colour pattern, narrow snout, long labial furrows, equal-size dorsal fins, and small anal fin (smaller than the dorsal fins). (Full article...)
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The pelagic thresher (Alopias pelagicus) is a species of thresher shark, family Alopiidae; this group of sharks is characterized by the greatly elongated upper lobes of their caudal fins. The pelagic thresher occurs in the tropical and subtropical waters of the Indian and Pacific Oceans, usually far from shore, but occasionally entering coastal habitats. It is often confused with the common thresher (A. vulpinus), even in professional publications, but can be distinguished by the dark, rather than white, color over the bases of its pectoral fins. The smallest of the three thresher species, the pelagic thresher typically measures 3 m (10 ft) long.
The diet of the pelagic thresher consists mainly of small midwater fishes, which are stunned with whip-like strikes of its tail. Along with all other mackerel sharks, the pelagic thresher exhibits ovoviviparity and usually gives birth to litters of two. The developing embryos are oophagous, feeding on unfertilized eggs produced by the mother. The young are born unusually large, up to 43% the length of the mother. Pelagic threshers are valued by commercial fisheries for their meat, skin, liver oil, and fins, and are also pursued by sport fishers. The International Union for Conservation of Nature assessed this species as endangered in 2019. (Full article...)
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Chaenogaleus is a genus of shark containing two species. Only one is extant.
Its construction, at the cost of 140 million US dollars, was financed by several backers.
The dam has a crest length of 2,600 metres (8,500 ft) and a height of 23 metres (75 ft). With a power output of 44 MW, the dam has an energy output of 200 million kilowatt-hours per year. The dam provides Bamako, Kati, Koulikoro, Ségou, Fana, Dioïla, Yanfolila and Kalana with electricity. It was brought into service in 1982, and renovated between 1996 and 2001.
The retaining basin of the dam forms the artificialLake Sélingué. The water level has a maximum height of 349 metres (1,145 ft) but varies throughout the year. When full the lake stores 2.2 cubic kilometres (0.53 cu mi) of water and has an area of 409 square kilometres (158 sq mi). It allows agriculture on the irrigated perimeters, managed by the Office of Rural Development of Sélingué, as well as fishing. (Full article...)
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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...)
Dam was designed by Hydroproject, a Russian hydrotechnical design firm, in collaboration with the Vietnamese company Power Construction No.1 JSC. The ground clearance works and relocation of people was completed by September 2010. Construction started on 5 January 2011; it was expected to be operational by 2017 with the first turbine put into operation in 2016, but the plant was inaugurated on 20 December 2016, one year ahead of the schedule, in a ceremony attended by the Deputy Prime Minister Trịnh Đình Dũng and other important personalities.
The power station has three Francis turbines with a capacity of 400 MW each. Turbines have been manufactured at the Alstom's plant in Tianjin, China. The total capacity of the station is 1,200 MW. It is the third largest hydroelectric power station in Vietnam and the third on the Da river. It is connected with the Hòa Bình Dam completed in 1994, and the Sơn La Dam, inaugurated in 2012. The Lai Châu hydropower projects cost VND 35,700 billion. (Full article...)
The Dubăsari Dam creates the Dubăsari reservoir (Romanian: Rezervuarul Dubăsari). The reservoir is 128 kilometres (80 mi) long and has an average width of 528 metres (1,732 ft). Water surface area is equal to 67.5 square kilometres (26.1 sq mi). (Full article...)
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The Tsiazompaniry Dam is a buttress dam on the Varahina-South River, a tributary of the Ikopa River, near Tsiazompaniry in the Analamanga Region of Madagascar. The dam was constructed by a French firm in 1956. It creates Lake Tsiazompaniry, the largest reservoir in the country, which has a surface area of 31 km2 (12 sq mi) and a storage volume of 260,000,000 m3 (210,000 acre⋅ft). A second buttress dam, 1 km (0.62 mi) northwest of the main dam helps withhold the reservoir. Water released from the dam supplies a regulated flow to hydroelectric power station at the Antelomita Dam downstream. Efforts to install a 5.25 MW power station at the base of the dam began in 2011. (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 Agusan Hydroelectric Plant, the downstream facility of two proposed plants, was constructed in Damilag, Manolo Fortich, Bukidnon to serve the immediate domestic and industrial requirements of the area. The watershed is small, and covers an area of around 25 km2 at the diversion dam. The run-of-river plant consists of two 800-kW turbine generators that use water from the Agusan River to generate electricity. It is connected to the local distribution grid Cepalco through the Transco distribution line. (Full article...)
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...)
Lake Caliraya was later connected with another man-made lake, Lumot Lake, to provide more water through a 2.3 km (1.4 mi) underground penstock. Later still the dam and lake were used as the upper reservoir for the Kalayaan Pumped-Storage Hydroelectric plant located west of Lake Caliraya, with Laguna de Bay as the lower reservoir. (Full article...)
Beris Dam (Malay: Empangan Beris) is a water supply dam located in Sik District, Kedah, Malaysia. The dam is a concrete-faced rockfill dam located in a narrow valley along Beris River, 1.6 km upstream from the river's confluence with Muda River.
The dam was completed in 2004 at a cost of RM360 million and is used for regulating the flow of water along the Muda River basin to augment water provision for irrigation of paddy or upland crops, for domestic and industrial water supply and other uses. The reservoir at its normal pool level covers an area of 13.7 km square whilst at maximum pool level inundates an area of 16.1 km square. It has a gross storage capacity of 122.4 million cubic metres with an effective storage of 144 million cubic metres. (Full article...)
The Baipaza Dam (Russian: Байпазинская ГЭС; Tajik: Нерӯгоҳи барқи обии Бойғозӣ) is a concrete face rock-fill dam on the Vakhsh River about 9 km (5.6 mi) southeast of Yovon in Khatlon Province, Tajikistan. A purpose of the dam is hydroelectric power generation and it supports a 600 MW power station. The first three 150 MW Francis turbine-generators were commissioned in 1985, the fourth in 1986. Its reservoir also holds water for the irrigation of some 40,000 ha (99,000 acres) in the Yovon and Obikiik Valleys to the west. This is accomplished by a 7.3-kilometre-long (4.5 mi) tunnel which runs from the right back of the reservoir and through a mountain to the valley. (Full article...)
The Tangevaerket Dam is an earth-fill embankment dam on the Gudenå River just east of the town of Tange in Viborg Municipality, Denmark. The primary purpose of the dam is hydroelectric power production and it supports a 3.3 MW power station which is the largest in the nation. The dam and power station were designed by Kristian Thomsen and S. A. Angelo in 1909. Construction did not begin until an agreement was reached with the Gudenå Commission. To build the dam, 500 men moved, by hand, about 300,000 m3 (390,000 cu yd) of earth. The power station was commissioned on 20 December 1920 and the reservoir flooded five homes and 22 farms. Its inauguration occurred on 8 January 1921. To produce power, water from the reservoir moves down a 500 m (1,600 ft) long and 6 m (20 ft) deep channel to the power station which houses three 1.1 MW Francis turbine-generators. The dam is also equipped with a fish ladder.
The power station's original concession for power production was set for 80 years. The concession has since been prolonged several times. Last in 2015 where it was prolonged by another 30 years. (Full article...)
The Afsluitdijk (Dutch:[ˈɑfslœydɛik]ⓘ; West Frisian: Ofslútdyk; Dutch Low Saxon: Ofsluutdiek; English: "Closure Dyke") is a major dam and causeway in the Netherlands. It was constructed between 1927 and 1932 and runs from Den Oever in North Holland province to the village of Zurich in Friesland province, over a length of 32 kilometres (20 mi) and a width of 90 metres (300 ft), at an initial height above Amsterdam Ordnance Datum of between 6.7 metres (22 ft) along the section at Friesland, and 7.4 metres (24 ft) where it crosses the deep channel of the Vlieter. The height at the greater sea depths west of Friesland was required to be a minimum of 7 metres everywhere when originally constructed.
Increases to the height of the Afsluitdijk have been made several times since 1958, when height increases were undertaken during regular maintenance periods as a result of the North Sea Flood of 1953, with the section between the Stevinsluizen and Lorentzsluizensluice complexes seeing the crest level raised to 7.8 metres. Major upgrade works commenced in 2019, with one of the design conditions being that only limited wave overtopping during the design storm condition be permitted. The design proposed by the successful contractor to meet this criterion will see a further increase in the height of the dam, by approximately 2 metres.
The Afsluitdijk is a fundamental part of the larger Zuiderzee Works, damming off the Zuiderzee, a salt water inlet of the North Sea, and turning it into the fresh water lake of the IJsselmeer. It is a major landwinning project and a quicker road-connection between the North and West of the Netherlands.
The highway on the Afsluitdijk was the initial demonstration site for a 130 km/h (81 mph) speed limit in the Netherlands. (Full article...)
The Miguel Alemán Dam is on the Tonto River in the Papaloapan Region of Oaxaca state in southern Mexico, just upstream from the town of Temascal or Nuevo Soyaltepec, forming the Miguel Alemán Lake with an area of 47,800 hectares. The dam operates in conjunction with the Cerro de Oro Dam, located on the Santo Domingo River to control floods in the Papaloapan basin in Veracruz state. Together with the 22,000 hectare reservoir of the Cerro de Oro, which is joined by a channel to the Miguel Alemán Lake, the combined capacity is 13,380 million cubic metres. The lake formed by the dam is scenic, providing income from fishing and tourism. The northwestern shore and islands have been declared a nature reserve. The dam includes the Temascal hydroelectric plant. (Full article...)
Sangtuda 1 Hydroelectric Power Plant (Russian: Сангтудинская ГЭС-1; Tajik: Нерӯгоҳи барқи обии Сангтӯда-1) is a hydroelectricpower plant, located on the Vakhsh River in Tajikistan. Construction commenced during the Soviet period in the 1980s, but halted in the beginning of the 1990s due to lack of financing when the station was about 20% complete. An agreement with Russia allowed to restart the construction, with four units entering service in 2008–2009. The plant was officially commissioned on 31 July 2009. Once working at full capacity, the plant will provide around 12% of Tajikistan's electricity output. (Full article...)
Sempor Dam (Indonesian: Waduk Sempor, Javanese: ꦮꦝꦸꦏ꧀ꦱꦺꦩ꧀ꦥꦺꦴꦂ, romanized: Wadhuk Sémpor) is an embankment dam on the Sempor River in District Gombong, Kebumen, Central Java Province, Republic of Indonesia. In addition to being a tourist attraction Sempor Dam is a source of irrigation water for farmers. It helps irrigate thousands of paddy fields in the delta. It also provides for flood control and has a 1 MW hydroelectric power station at its base. Construction on the dam started in 1967 but in the same year water from flash floods over-topped it, causing the dam to fail on 29 November 1967. The wave of water killed 160 people in three towns, including Magelang. and delivered widespread damage to the area. Construction later restarted on the dam and it was completed in 1978. Its power station was later commissioned in 1980. (Full article...)
The Meghri hydroelectric project (also known as the Meghri Dam or Aras Watershed Dam) is a hydroelectric project planned on the Aras River near Armenia's southern town of Meghri on the Armenia–Iran border.
The joint Iranian–Armenia project was proposed in the 1990s and was discussed between Iranian and Armenian authorities. Intergovernmental agreements between Armenia and Iran were signed in 2007 and 2008. On 14 April 2009, energy ministries of Armenia and Iran signed a memorandum on financing construction of the Meghri power station of Armenian side. The dam and power stations construction contract was signed on 16 October 2010 with Farab Sepasad Company. A ceremony on 17 November 2012, attended by Iran's Minister of Energy and the Armenian President, officially began construction.
The basic studies were carried out by Arm-Hydroenergo-Project Company and Mahab-E-Qods Consulting Engineers Company in 1999. The Meghri station was to be operated by Iran for 15 years after which it will be returned to Armenia free of charge. However, construction has been delayed. As of 2017, the Armenian government’s Deputy Minister of Energy Infrastructures and Natural Resources Hayk Harutyunyanays said "Although the agreement has long been in force, the Iranian company has not made any investments to this day, so the governments of Armenia and Iran have to look for another investor." The project is expected to cost US$400 million. (Full article...)
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Ulla-Førre is a hydropower complex in Southern Norway. It is situated along the borders of the municipalities of Suldal and Hjelmeland (in Rogaland county) and Bykle (in Agder county), Norway. It has an installed capacity of approximately 2,100 megawatts (2,800,000 hp), and the annual average production is 4.45 TWh (16.0 PJ) (1987–2006), while its reservoir capacity is about 7.8 TWh (28 PJ); at full production, it can last seven to eight months. The complex includes the artificial lake Blåsjø, which is made by dams around 1,000 metres (3,300 ft) above the sea level. The hydroelectric power stations in the complex are Saurdal, Kvilldal, Hylen and Stølsdal, operated by Statkraft. (Full article...)
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Toker Dam is the fourth largest dam in Eritrea. Construction was begun in 1997 and completed in 2001, despite having to be halted for a few months in 1998 when Ethiopia and Eritrea were at war. Its primary designer was Natural Resources Consulting Engineers from Colorado, USA. Furthermore, NRCE Inc., was the primary consultant on the project. The construction contractor was Keagnam of South Korea.
The project was designed to provide modern and effective service to the City of Asmara and neighboring villages. It further provides safe drinking water for the local population. The dam is a roller compacted concrete dam, and was one of the highest in sub-Saharan Africa at the time it was built. (Full article...)
The Imha Dam is an embankment dam on the Banbyeoncheon River, a tributary of the Nakdong River, 14 km (9 mi) east of Andong in Gyeongsangbuk-do province, South Korea. The purpose of the dam is flood control, water supply and hydroelectric power generation. Construction on the dam began in 1987 and it was complete in 1991. The 73 m (240 ft) tall rock-fill, central earth-core dam creates a reservoir with a capacity of 595,000,000 m3 (482,374 acre⋅ft) and supplies a 50 MW power station with water. It supplies water for both municipal and industrial uses to Gumi, Dagu, Masan, Changwon, Jinhae, Ulsan, and Busan. (Full article...)
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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.
Lake Chivero is a reservoir on the Manyame River in Zimbabwe. It was formerly called Lake McIlwaine in memory of Sir Robert McIlwaine, a former judge of the High Court and founder of Southern Rhodesia's (later Rhodesia's, now Zimbabwe's) soil and water conservation movement.
Located southwest of Harare, it provides the main water supply for the city. The lake was constructed over two-and-a-half years and opened to the public in 1952. The dam wall is 400 metres long.
The water is also used for irrigation purposes and commercial fishing. Some of the fishes that are found in the lake include common grass carp, tigerfish, black bream, Clarias gariepinus, yellowfish, and green-headed bream.
The lake and hinterland are protected as part of Lake Chivero Recreational Park. The lake was designated a Ramsar wetland of international importance on 3 January 2013.
Remembrance Island is a small island in the reservoir. (Full article...)
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The Punchiná Dam is an embankment dam on the Guatapé River 17 kilometres (11 mi) east of San Carlos in Antioquia Department, Colombia. The dam creates Punchiná Reservoir which is part of the 1,240 megawatts (1,660,000 hp) San Carlos Hydroelectric Power Plant. The power plant was completed in two 620 megawatts (830,000 hp) stages, the first was completed in 1984 and the second in 1987. It is the largest power station in Colombia. (Full article...)
It is a reservoir with a surface area of about 88 km2 (34 sq mi) and is fed by the river Þjórsá, which comes down from the glacierHofsjökull. On its southern end, Þórisvatn is used to generate electricity at a power station. It is like other Icelandic lakes, which are mostly glacial lakes or volcanic lakes.
The lake grew from about 70 km2 to 86 km2[contradictory] with the construction of the power station and was previously only the second largest lake in the country. (Full article...)
The first European hydroelectric power plant was built in Croatia (many people worked together to make this possible). According to Nikola Tesla's patents, it was operational two days after Niagara Falls' installation of the first hydroelectric power plant in the world. A turbine, two generators (42 Hz, 550 kW) and a transformer made by the Hungarian company Ganz were built under the Skradinski Buk waterfall. The Jaruga is one of the oldest power-generating facilities in the world. Its present location dates back to 1903, when it was moved from the nearby original Jaruga power station built in 1895. (Full article...)
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The Lower Se San/Sre Pok 2 scheme is a proposed hydroelectric dam to be located in Stung Treng Province, Cambodia on the Tonle Sre Pok some 2 kilometres (1.2 mi) upstream of its confluence with the Se San, and about 37 kilometres (23 mi) upstream of the confluence of the combined Sre Pok, Se San and Se Kong rivers with the Mekong mainstream.
Prefeasibility Study, the project aims to construct and operate an installed capacity 222 megawatts (298,000 hp) low head hydroelectric generating facility on the Sre Pok River, generating annually 1,060 GWh (3,800 TJ), run-of-river dam, reservoir 120 square kilometres (46 sq mi) Main components include construction of a concrete gravity dam, the powerhouse and generating equipment, environmental and social mitigation measures, and the 220-kV transmission line to Stung Treng and onwards to the Vietnamese border to interconnect with the Vietnamese grid backbone.
The scheme has a much smaller reservoir area (120 square kilometres (46 sq mi)) than the Lower Se San 2 site (355 square kilometres (137 sq mi)) and consequently a lesser environmental impact. The number of inhabitants in the reservoir area for resettlement is also significantly less. The dam is low in height, but could still have a significant impact on navigation and fish migration, which is a particular concern at all sites in this area. Allowances have been made in the scheme design and cost estimate for mitigation of these impacts, so far as is possible.
Per MIME report to RPTCC-4 meeting (Yangon, Sept. 2005), commissioning of 222 MW Lower Sre Pok HPP will be in 2017.
Impact: Up to 1000 people may rewire resettlement. (Full article...)
{{ Transclude list item excerpts as random slideshow | List of mountain ranges | section=Mountain ranges on Earth }} Select from Earth section, avoiding Moon
The highest peaks in the range are its fourteeners, Castle Peak (14,265 ft), Maroon Peak (14,156 ft), Capitol Peak (14,130 ft), Snowmass Mountain (14,092 ft), Pyramid Peak (14,018 ft), and North Maroon Peak (14,014 ft). Maroon Peak and North Maroon Peak are collectively known as the Maroon Bells, a popular destination for recreation alpinism. Mount Sopris (12,953 ft) sits at the northwest end of the range and dominates the skyline of the lower Roaring Fork Valley and the town of Carbondale, Colorado, serving as an unofficial symbol of the area. Additional notable peaks in the range include:
Whitehouse Mountain, 11,975 ft (3,650 m), northwest of Treasure Mountain
The range provides a formidable barrier to travel and is traversed only by backroad passes and trails, including Schofield Pass, Pearl Pass, and Taylor Pass. State Highway 133 traverses McClure Pass, at the western end of the range. The range has been the site of mining activity since the days of the Colorado Silver Boom, which saw the founding of mining towns such as Aspen and Ashcroft. In the late 19th century, the western and southern flank of the range became the site of intense coal mining activity which continues to the present day. Treasure Mountain, overlooking the town of Marble, is home to the famous Yule Marble Quarry. Quarried marble was used to create The Tomb of the Unknowns, the Lincoln Memorial, Denver Post Office and other buildings. The range receives a great deal of snowfall due to its position to the west of the continental divide and the westerly origin of many winter storms. This is exploited by the ski areas in the vicinity of Aspen, which are located on the flanks of smaller mountains alongside the Roaring Fork Valley. (Full article...)
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The Sierra de Chinajá is a low karsticmountain range in Guatemala. It is situated in the north of the department of Alta Verapaz and covers an area of approximately 135 km2 (52 sq mi).<-- 2023-02-27: Google search of the title did not provide any hits of the PDF --> Its highest peak has an altitude of 838 m (2,749 ft).
The mountain range is isolated from other ranges and forms the last major topographic landform between the highlands of the Sierra de Chamá and the lowland plains of Petén. (Full article...)
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The Columbia Mountains are a group of mountain ranges along the Upper Columbia River in British Columbia, Montana, Idaho and Washington. The mountain range covers 135,952 km² (52,491 sq mi). The range is bounded by the Rocky Mountain Trench on the east, and the Kootenai River on the south; their western boundary is the edge of the Interior Plateau. Seventy-five percent of the range is located in Canada and the remaining twenty-five percent in the United States; American geographic classifications place the Columbia Mountains as part of the Rocky Mountains complex, but this designation does not apply in Canada (despite a British Columbia government tourism campaign to rebrand their southern portion as the "Kootenay Rockies"). Mount Sir Sandford is the highest mountain in the range, reaching 3,519 metres (11,545 ft). (Full article...)
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The Sierra de los Cuchumatanes is the highest non-volcanic mountain range in Central America. Its elevations range from 500 m (1,600 ft) to over 3,800 m (12,500 ft), and it covers a total area of c. 16,350 km2 (6,310 sq mi). With an area of 1,500 km2 (580 sq mi) situated above 3,000 m (9,800 ft), it is also the most extensive highland region in Central America. The Sierra de los Cuchumatanes is located in western Guatemala in the departments of Huehuetenango and El Quiché. Its western and south-western borders are marked by the Seleguá River, which separates it from the Sierra Madre volcanic chain. Its southern border is defined by the Río Negro, which flows into the Chixoy River, which turns northwards and separates the Cuchumatanes from the mountains in the Alta Verapaz region. The highest peaks, which reach up to 3,837 m (12,589 ft), are located in the department of Huehuetenango. (Full article...)
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The Dieng Volcanic Complex (Javanese: ꦢꦶꦲꦾꦁ, romanized: Dihyang) is a volcanic complex located on the Dieng Plateau in Central Java, Indonesia, a complex of volcanoes. The volcanic complex consists of two or more stratovolcanoes, more than 20 small craters, and Pleistocene to Holocene-age volcanic cones. It covers a 6 by 14 kilometres (3.7 by 8.7 mi) area. The Prahu stratovolcano was truncated by a large Pleistocene caldera and then filled by parasitic cones, lava domes, and craters which is 120 °C (248 °F). Some of them are turned into lakes. Toxic volcanic gas has caused fatalities and is a hazard at several craters. On 20 February 1979, 149 people died of gas poisoning in Pekisaran village on the plateau near the Sinila crater. The area is also home to a major geothermal project. (Full article...)
The Svecofennian orogeny is a series of related orogenies that resulted in the formation of much of the continental crust in what is today Sweden and Finland plus some minor parts of Russia. The orogenies lasted from about 2000 to 1800 million years ago during the Paleoproterozoic Era. The resulting orogen is known as the Svecofennian orogen or Svecofennides. To the west and southwest the Svecofennian orogen limits with the generally younger Transscandinavian Igneous Belt. It is assumed that the westernmost fringes of the Svecofennian orogen have been reworked by the Sveconorwegian orogeny just as the western parts of the Transscandinavian Igneous Belt has. The Svecofennian orogeny involved the accretion of numerous island arcs in such manner that the pre-existing craton grew with this new material from what is today northeast to the southwest. The accretion of the island arcs was also related to two other processes that occurred in the same period; the formation of magma that then cooled to form igneous rocks and the metamorphism of rocks. (Full article...)
The massif has a length of 25 kilometres (16 mi) from the northwest to the southeast and a width of 14 kilometres (8.7 mi). It is located east of the town Ștei, Bihor County and north of the town of Brad, Hunedoara County.
The highest peak is Cucurbăta Mare, with an elevation of 1,849 metres (6,066 ft); this also the highest peak of the Apuseni Mountains. Other high peaks are Buteasa (1,790 m), Cârligatele (1,694 m), Piatra Grăitoare (1,658 m), and Bohodei (1,654 m).
The Vlădeasa Massif [ro] is a volcanic range extension of the Bihor Mountains to the north, reaching a maximum height of 1,836 metres (6,024 ft). (Full article...)
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The Black Mountains (Welsh: Y Mynydd Du or sometimes Y Mynyddoedd Duon) are a group of hills spread across parts of Powys and Monmouthshire in southeast Wales, and extending across the England–Wales border into Herefordshire. They are the easternmost of the four ranges of hills that comprise the Brecon Beacons (or Bannau Brycheiniog) National Park, and are frequently confused with the westernmost, which is known as the Black Mountain. The Black Mountains may be roughly defined as those hills contained within a triangle defined by the towns of Abergavenny in the southeast, Hay-on-Wye in the north and the village of Llangors in the west. Other gateway towns to the Black Mountains include Talgarth and Crickhowell. The range of hills is well known to walkers and ramblers for the ease of access and views from the many ridge trails, such as that on the Black Hill in Herefordshire, at the eastern edge of the massif. The range includes the highest public road in Wales at Gospel Pass, and the highest point in southern England at Black Mountain. (Full article...)
The range extends for approximately 8 miles (13 km) in an arc that begins at New Hampshire Route 11A in Gilford and runs south, then curves east through the northern end of Gilmanton, before ending in the town of Alton, where it overlooks Alton Bay of Lake Winnipesaukee.
The named summits in the range, from northwest to southeast, are Mount Rowe (1,690 ft or 520 m), Gunstock Mountain (2,240 ft or 680 m), Belknap Mountain, Straightback Mountain (1,890 ft or 580 m), and Mount Major (1,786 ft or 544 m). A cluster of several unofficially named summits with elevations ranging from 1,806 to 2,001 feet (550 to 610 m) are on the main crest of the range between Belknap Mountain and Straightback Mountain, surrounding Round Pond, itself located near the crest of the range at 1,652 feet (504 m) above sea level. A secondary ridge extends southwest from Belknap Mountain to the Gilford/Gilmanton line, containing, from north to south, the summits of Piper Mountain (2,044 ft or 623 m) and Whiteface Mountain (1,670 ft or 510 m).
The range is entirely in the Merrimack River watershed. The northeast side of the range drains via several small brooks to Lake Winnipesaukee, the outlet of which is the Winnipesaukee River, which drains westward to form the Merrimack. The west side of the range drains via the Gunstock River into Lake Winnipesaukee, and the extreme southwest end of the range, near Whiteface Mountain, drains west via the Tioga River to the Winnipesaukee River. The south side of the range, including Round Pond, drains south via the Suncook River to the Merrimack.
Paraguay (/ˈpærəɡwaɪ/; Spanish pronunciation:[paɾaˈɣwaj]ⓘ), officially the Republic of Paraguay (Spanish: República del Paraguay; Guarani: Paraguái Tavakuairetã), is a landlocked country in South America. It is bordered by Argentina to the south and southwest, Brazil to the east and northeast, and Bolivia to the northwest. It has a population of around 6.1 million, nearly 2.3 million of whom live in the capital and largest city of Asunción, and its surrounding metro area.
Spanish conquistadores arrived in 1524, and in 1537 established the city of Asunción, the first capital of the Governorate of the Río de la Plata. During the 17th century, Paraguay was the center of Jesuit missions, where the native Guaraní people were converted to Christianity and introduced to European culture. After the expulsion of the Jesuits from Spanish territories in 1767, Paraguay increasingly became a peripheral colony. Following independence from Spain in the early 19th century, Paraguay was ruled by a series of authoritarian governments. This period ended with the disastrous Paraguayan War (1864–1870), during which the country lost half its prewar population and around 25–33% of its territory. In the 20th century, Paraguay faced another major international conflict—the Chaco War (1932–1935) against Bolivia—in which Paraguay prevailed. The country came under a succession of military dictators, culminating in the 35 year regime of Alfredo Stroessner, which lasted until his overthrow in 1989 by an internal military coup. This marked the beginning of Paraguay's current democratic era.
Although one of only two landlocked countries in South America (Bolivia is the other), Paraguay has ports on the Paraguay and Paraná rivers that give exit to the Atlantic Ocean, through the Paraná-Paraguay Waterway. The majority of Paraguay's 6 million people are mestizo, and Guarani culture remains widely influential; more than 90% of the population speak various dialects of the Guarani language alongside Spanish. Paraguay's GDP per capita PPP is the seventh in South America. In a 2017 Positive Experience Index based on global polling data, Paraguay ranked as the "world's happiest place". (Full article...)
The Serra de Tramuntana (Catalan pronunciation:[ˈsɛrəðətɾəmunˈtanə], Spanish: Sierra de Tramontana) is a mountain range running southwest–northeast which forms the northern backbone of the Spanish island of Mallorca. It is also the name given to the comarca of the same area. On 27 June 2011, the Tramuntana Range was awarded World Heritage Status by UNESCO as an area of great physical and cultural significance. (Full article...)
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The Star Range is an 8-mile (12 km) long, small mountain range located in central Beaver County, Utah. The range is "star"-shaped as small ridges end at peaks, like fingers of a hand. Another adjacent range sequence southwest, the Shauntie Hills has other fingers of the star-shape.
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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Precordillera is a Spanish geographical term for hills and mountains lying before a greater range, similar to foothills. The term is derived from cordillera (mountain range)—literally "pre-mountain range"—and applied usually to the Andes.
Some places usually called precordillera are:
Andean mountains east of the main ranges of Andes in Argentina. It is separated from the much higher Frontal Cordillera to the west by Uspallata Valley in Argentina. Precordillera mountains reach around 3,000 m a.s.l. in Sierras de Villavicencio.
Used all over Chile from north to south as a morphological unit lying just between the Andes and the Intermediate Depression.
More than one hundred million years ago during the Nevadan orogeny, granite formed deep underground. The range started to uplift less than five million years ago, and erosion by glaciers exposed the granite and formed the light-colored mountains and cliffs that make up the range. The uplift caused a wide range of elevations and climates in the Sierra Nevada, which are reflected by the presence of five life zones (areas with similar plant and animal communities). Uplift continues due to faulting caused by tectonic forces, creating spectacular fault blockescarpments along the eastern edge of the southern Sierra.
The Sierra Nevada has played an important role in the history of California and the United States. The California Gold Rush occurred in the western foothills from 1848 through 1855. Due to its inaccessibility, the range was not fully explored until 1912. (Full article...)
The term "arfak" came from arfk the language of the coastal Biak people, meaning "people who sleep over fire", to refer to how the Arfak warm their houses by putting hot ember below their Rumah Kaki Seribu. Locally the mountain is called "Gunung Indon" or "Indonga" meaning "big mountain" in Hatam language. Located in the east and central regions of the Bird's Head Peninsula, these mountains rise steeply from the sea, with little or no coastal plain surrounding them. Mount Arfak, at 2,955 m (9,695 ft), can be viewed from the provincial capital, Manokwari, and is the highest point in West Papua and the Bird's Head Peninsula.
Since Dutch colonial times the range has been one of the most frequently explored and best known regions of West Papua for bird watching. Along with the Tamrau Mountains in the north, the two ranges have been divided by the grassy Kebar Valley, which is the heartland of many indigenous people, with a variety of backgrounds. Found near the town of Manokwari, the mountains are an important and threatened site of biodiversity, part of the Vogelkop montane rain forestsecoregion. Multiple tribes of indigenous peoples, many who speak mutually unintelligible languages such as Hatam, Meyah and Sougb all call the Arfak Mountains their home. They ultimately are the guardians of the future of the exquisite, yet increasingly threatened bird species found throughout this rugged region. (Full article...)
After the invasion of the Waikato, parts of the Hakarimatas were confiscated in 1864. 1,850 hectares (4,600 acres) of native forest on the range are protected as a scenic reserve. A council supported community group, the Hakarimata Restoration Trust, created in 2001, is helping care for the range. (Full article...)
In the northern subalpine regions, the various ranges are easily identifiable by geographical separations, such as the Voreppe Gorge between Vercors and Chartreuse, or Chambéry, which sits in a valley between the Bauges and Chartreuse ranges. In the southern subalpine regions, the ranges are generally disorganized and lack the wide, deep valleys that divide them in the north.
There are several small plains between the range and the Atlantic Ocean coastline. Rivers have short courses in the range, and most of them flow to the north into the Atlantic. (Full article...)
This mountain range is situated between the municipalities of Lauro Müller and Bom Jardim da Serra, and its highest point is situated at 1,460 metres (4,790 feet) above sea level. In the highest areas of this place, the Atlantic Ocean, located about 100 km (62 mi) away, can be spotted on clear days. Frosts are common and snowfalls can occur in the highest areas. (Full article...)
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The Grampian Mountains (Scottish Gaelic: Am Monadh) is one of the three major mountain ranges in Scotland, that together occupy about half of Scotland. The other two ranges are the Northwest Highlands and the Southern Uplands. The Grampian range extends southwest to northeast between the Highland Boundary Fault and the Great Glen. The range includes many of the highest mountains in the British Isles, including Ben Nevis (whose peak contains the highest point in the British Isles at 1,345 m or 4,413 ft above sea level) and Ben Macdui (whose peak contains second-highest at 1,309 m or 4,295 ft).
There is some ambiguity about the extent of the range, and until the nineteenth century, they were generally considered to be more than one range, which all formed part of the wider Scottish Highlands. This view is still held by many today, and they have no single name in the Scottish Gaelic language or the Doric dialect of Lowland Scots. In both languages, a number of names are used. The name "Grampian" has been used in the titles of organisations covering parts of Scotland north of the Central Belt, including the former local government area of Grampian Region (translated into Scots Gaelic as Roinn a' Mhonaidh), NHS Grampian, and Grampian Television. (Full article...)
The Swartberg mountains (black mountain in Afrikaans) are a mountain range in the Western Cape province of South Africa. It is composed of two main mountain chains running roughly east–west along the northern edge of the semi-arid Little Karoo. To the north of the range lies the other large semi-arid area in South Africa, the Great Karoo. Most of the Swartberg Mountains are above 2000 m high, making them the tallest mountains in the Western Cape. It is also one of the longest, spanning some 230 km from south of Laingsburg in the west to between Willowmore and Uniondale in the east. Geologically, these mountains are part of the Cape Fold Belt.
Following the death of President Juan Perón in 1974, his widow and vice president, Isabel Perón, ascended to the presidency, before being overthrown in 1976. The following military junta, which was supported by the United States, persecuted and murdered thousands of political critics, activists, and leftists in the Dirty War, a period of state terrorism and civil unrest that lasted until the election of Raúl Alfonsín as president in 1983.
The range is a large fault block of Cenozoic age created by the movements of the Santa Ynez Fault. A very narrow range, the Santa Ynez Mountains rise quickly on its north side and drops off equally dramatically along the range's south face along the Gaviota Coast. The Santa Ynez Mountains begin as a series of volcanic hills near Point Arguello, and gradually transitions eastward into a single, well-defined ridge extending from Gaviota Peak to Matilija Creek. The range is approximately contiguous with the Topatopa Mountains beyond to the east, which terminates abruptly at Sespe Creek.
The climate of the range is Mediterranean with most of the precipitation falling between November and March. Most of the range lies in the California chaparral and woodlands ecoregion. At the crest and on the north slope, the rainier regions support extensive oak woodlands, mixed with other broadleafed species such as madrone, sycamore and bay laurel, along with some conifers, primarily Coulter pines. (Full article...)
Notable peaks in this mountain range include Mount Delo (3600 metres) and Mount Tabala (1650 metres). Tabala is known for its hot springs. Vittorio Bottego reached the top of the Amaro mountains on 23 March 1896, then visited Prince Eugene Ruspoli's grave before travelling on to Lake Abaya, which they named after Queen Margherita. The name "Amara" was used by Arthur Donaldson Smith when he wrote about his explorations in 1897, and Vannutelli (travelled here in 1899) called them the "Amarr". Early travelers who visited the range describe the higher summits as bare open downs, easy of access, with bamboo forests below. There is little mountaineering interest. (Full article...)
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The Accursed Mountains (Albanian: Bjeshkët e Nëmuna; Serbo-Croatian: Проклетије, Prokletije, pronounced[prɔklɛ̌tijɛ]; both translated as "Cursed Mountains"), also known as the Albanian Alps (Albanian: Alpet Shqiptare), is a mountain range in coastal Southeast Europe adjacent to the Adriatic Sea. It is the southernmost subrange of the 1,000-kilometre-long (621 mi) Dinaric Alps range (Dinarides), extending from northern Albania to southern Kosovo and northeastern Montenegro. Maja Jezercë, standing at 2,694 m (8,839 ft), is the highest point of the Accursed Mountains and of all Dinaric Alps, and the fifth highest peak in Albania. The range includes the mountain Zla Kolata, which, at 2,534 m (8,314 ft), is the tallest mountain in Montenegro. The range also includes the mountain Gjeravica, which, at 2,656 m (8,714 ft), is the second tallest mountain in Kosovo. One of the southernmost glacial masses in Europe was discovered in the Albanian part of the range in 2009. (Full article...)
The park was enlarged in 2003, and now covers an area of 963 km2 (372 sq mi). Rondane lies just to the east of the Gudbrandsdalen valley and two other mountain areas, Dovre and Jotunheimen are nearby. Dovre National Park lies a very short distance to the north of this park. (Full article...)
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The Itcha Range, also known as the Itchas, is a small isolated mountain range in the West-Central Interior of British Columbia, Canada. It is located 40 km (25 mi) northeast of the community of Anahim Lake. With a maximum elevation of 2,375 m (7,792 ft), it is the lowest of three mountain ranges on the Chilcotin Plateau extending east from the Coast Mountains. Two mountains are named in the Itcha Range; Mount Downton and Itcha Mountain. A large provincial park surrounds the Itcha Range and other features in its vicinity. More than 15 animal species are known to exist in the Itcha Range area, as well as a grassland community that is limited only to this location of British Columbia. The Itcha Range is within territory which has been occupied by aboriginal peoples for millennia. This area has a relatively dry environment compared to the Coast Mountains in the west.
In contrast to most mountain ranges in British Columbia, the Itcha Range represents an inactive shield volcano. This highly dissected volcanic edifice consists of a variety of rock types, including basanite, hawaiite, trachyte, rhyolite, phonolite and alkali olivine basalt. They were deposited by different types of volcanic eruptions characterized by passive lava flows and explosivity. Two stages of eruptive activity have been identified at the volcano along with three sub-phases that are limited only to the first stage of development. The main body of the Itcha Range is between 3.8 and 3.0 million years old and thus over two million years ago it passed the most active shield stage of life. A period of dormancy lasting for almost a million years followed, which was interrupted by the post-shield stage of volcanism 2.2 to 0.8 million years ago. More recent volcanic activity in and around the Itcha Range might have occurred in the last 340,000 years to produce cinder cones.
The Itcha Range is part of an east–west trending volcanic zone called the Anahim Volcanic Belt. This consists of large shield volcanoes, small cinder cones, lava domes and lava flows that become progressively younger from west to east. Several explanations have been made regarding the creation of this feature, each citing a different geologic process. If volcanic activity were to resume at the Itcha Range, Canada's Interagency Volcanic Event Notification Plan (IVENP) is prepared to notify people threatened by eruptions. (Full article...)
The Purcells are shown on some United States maps as the Percell Mountains, where their southern limit protrudes into the states of Idaho and Montana, abutting Lake Koocanusa, a reservoir on the Kootenai River. American geographic classifications consider the Percells to be part of the Rocky Mountains but in Canada that terminology is reserved for ranges on the east side of the Rocky Mountain Trench. In the Purcell Mountains, most of the peaks are near or above 10,000 feet in elevation.
Although the Coast Mountain Range is usually referred to as the westernmost range of the Pacific Cordillera (since it is the westernmost range on the main landmass at that point), the Insular Mountains are the true westernmost range. (Full article...)
One of the earliest historical references to these mountains may be related to the Xiongnu word Qilian (traditional Chinese: 祁連; simplified Chinese: 祁连; pinyin: Qílián), which, according to Tang commentator Yan Shigu, is the Xiongnu word for "sky" or "heaven". Sima Qian, in the Records of the Grand Historian, mentioned Qilian in relation to the homeland of the Yuezhi, and the term is believed to refer to the Tian Shan rather than the range 1,500 kilometres (930 mi) further east now known as the Qilian Mountains. The name of the Tannu-Ola mountains in Tuva has the same meaning. The Chinese name Tian Shan is most likely a direct translation of the traditional Kyrgyz name for the mountains, Teñir Too.
The Tian Shan is sacred in Tengrism. Its second-highest peak is known as Khan Tengri, which may be translated as "Lord of the Spirits". At the 2013 Conference on World Heritage, the eastern portion of Tian Shan in western China's Xinjiang Region was listed as a World Heritage Site. The western portion in Kazakhstan, Kyrgyzstan, and Uzbekistan was then listed in 2016. (Full article...)
The term Bernina Alps can also be used in an extended sense to include both the Bernina and Bregaglia ranges; this is the area coloured red on the map (right) and labelled 'Bernina Alpen'. (Full article...)
The Columbia Mountains are a group of mountain ranges along the Upper Columbia River in British Columbia, Montana, Idaho and Washington. The mountain range covers 135,952 km² (52,491 sq mi). The range is bounded by the Rocky Mountain Trench on the east, and the Kootenai River on the south; their western boundary is the edge of the Interior Plateau. Seventy-five percent of the range is located in Canada and the remaining twenty-five percent in the United States; American geographic classifications place the Columbia Mountains as part of the Rocky Mountains complex, but this designation does not apply in Canada (despite a British Columbia government tourism campaign to rebrand their southern portion as the "Kootenay Rockies"). Mount Sir Sandford is the highest mountain in the range, reaching 3,519 metres (11,545 ft). (Full article...)
Its highest peak, Black Rock (Albanian: Guri i Zi; Macedonian: Црн Камен), reaches a height of 2,257 m (7,405 ft), marking the delineation point for both countries. (Full article...)
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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.
{{ Transclude list item excerpts as random slideshow | List of dams and reservoirs | section=Africa | sectiononly=yes }} Should pick only the international dams
Djorf Torba Dam is a dam in Kenadsa District, Béchar Province, Algeria, crossing the Oued Guir about 50 kilometres (31 mi) west of the capital, Béchar. It is used for the purposes of irrigation and water supply. The area around the head of the dam features a number of notable ancient monuments. The dam has resulted in a significant reduction in the flow of Oued Guir and Oued Saoura in locations downstream of the dam. (Full article...)
The site for the dam at Bumbuna Falls was first identified in 1971, and construction was begun in 1975. Work was halted in May 1997, about 85% completed, due to the Sierra Leone Civil War, and did not restart until 2005. The project was completed and went online in 2009. Nearly a third of the dam's US$327 million cost ($103 million) was supplied by the African Development Bank. A 26 January 2005 report noted that 33 villages would be affected by the dam, although only one (of 16 households and 135 people) would require resettlement.
The dam has a maximum height of 87 metres (285 ft), a length of 400 metres (1,300 ft) at the crest and a volume of 2,500,000 cubic metres (88,000,000 cu ft). The volume of the reservoir created is 410,000,000 cubic metres (1.4×1010 cu ft), 428,000,000 cubic metres (1.51×1010 cu ft) or 480,000,000 cubic metres (1.7×1010 cu ft). There are two Francis turbines, each rated for 25 megawatts (34,000 hp).
After completion, the project has been plagued with problems, and barely produces 10 megawatts (13,000 hp) or 25 megawatts (34,000 hp) as of 2013.
A second phase is planned, for a 110-megawatt (150,000 hp) power station. In June 2011, the government announced it had awarded the $750 million Phase II project to Joule Africa, a UK-based company. This will entail a second dam and plant. Construction was set to begin in 2014 and continue on until at least 2017. (Full article...)
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 Capanda Dam is a hydroelectric dam on the Kwanza River in Malanje Province, Angola. Built in 1987–2007 by the Russian company Tekhnopromexport, general designer - the institute Hydroproject (Chief Engineer - Ph.D Fedosov V.E.) The facility generates power by utilizing four turbines and 130 megawatts (170,000 hp) each, totalling the installed capacity to 520 megawatts (700,000 hp) . Total cost of US$4 billion. An additional cost of more than US$400 million was spent in repairing the damage caused during UNITA's occupation of the area at the time of the Angolan Civil War in 1992 and 1999. (Full article...)
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Lake Chivero is a reservoir on the Manyame River in Zimbabwe. It was formerly called Lake McIlwaine in memory of Sir Robert McIlwaine, a former judge of the High Court and founder of Southern Rhodesia's (later Rhodesia's, now Zimbabwe's) soil and water conservation movement.
Located southwest of Harare, it provides the main water supply for the city. The lake was constructed over two-and-a-half years and opened to the public in 1952. The dam wall is 400 metres long.
The water is also used for irrigation purposes and commercial fishing. Some of the fishes that are found in the lake include common grass carp, tigerfish, black bream, Clarias gariepinus, yellowfish, and green-headed bream.
The lake and hinterland are protected as part of Lake Chivero Recreational Park. The lake was designated a Ramsar wetland of international importance on 3 January 2013.
Remembrance Island is a small island in the reservoir. (Full article...)
Kainji Dam is a dam across the Niger River in Niger State of Central Nigeria. Construction of the dam was carried out by Impregilo (a consortium of Italian Civil Engineering Contractors) to designs by Joint Consultants, Balfour Beatty and Nedeco, and began in 1964 to be completed in 1968. The total cost was estimated at US$209 million (equivalent to about US$1.5 billion in 2023 dollars), with one-quarter of this amount used to resettle people displaced by the construction of the dam and its reservoir, Kainji Lake. (Full article...)
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 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 many more. (Full article...)
Tendaho Dam is an earth-filled dam in the eastern Afar Region of Ethiopia. It is situated on the Awash River, and its reservoir also receives the output of the Mille River. The dam is a project of the Ethiopian Water Works Construction Enterprise (EWWCE). Project planning began in 2005, with construction occurring from 2010 to 2014. The dam is aimed at providing irrigation primarily for the Tendaho Sugar Factory sugar cane plantation., as well as drinking water for the region. Out of the 60,000 hectares of land planned to be irrigated, 10,000 would be allotted for social services and the community, and the remaining 50,000 hectares for cultivating sugar cane for the sugar factory.
The nearest towns are Logiya, situated just north of the dam, and Semera, which has an airstrip (Semera Airport) and a university. (Full article...)
The Félou Hydroelectric Plant (French: Centrale hydroélectrique de Félou) is a hydroelectric installation at the Félou Falls on the Sénégal River in Mali. It has three water turbines capable of generating 62.3 MW. The current power station replaced an older one built in the 1920s. Construction of the new power station began in October 2009 and was financed by the World Bank. It is the third Senegal River Basin Development Authority project on the river and was completed in 2014. The existing weir was refurbished with the previous 2 metres (6.6 ft) height maintained. In 1927, the previous hydroelectric power station was commissioned. It was refurbished in 1992 and had an installed capacity of 600 kW.
At maximum output the three 21 MW turbines pass a total of 500 cubic metres per second (18,000 cu ft/s) of water. Between August and November the water flowing in the river generally exceeds this value allowing the plant to operate at full capacity and the excess water to pass over the weir. During the dry season (December to July) the electricity generated is reduced to about a third of the maximum output as the flow of water is limited to the 150–200 cubic metres per second (5,300–7,100 cu ft/s) released from the Manantali Dam.
The total estimated cost is 241 million US dollars. The construction of the plant was completed in 2014. (Full article...)
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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...)
Completed in 1981, it was originally envisaged to become part of the Eastern National Water Carrier, a scheme to supply water to Namibia's capital Windhoek from the Okavango River, 1,000 kilometres (620 mi) to the north on the Angolan border. The scheme was never completed. Omatako Dam today only contains floods and supplies water to the Von Bach Dam. As such, it is one of three dams supplying the capital Windhoek with water. (Full article...)
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...)
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The Bin el Ouidane Dam is an arch dam located 28 kilometres (17 mi) south of Beni Mellal on the El-Abid River in Azilal Province, Morocco. Designed by Coyne et Bellier and constructed between 1949 and 1953, the purpose of the dam is hydroelectric power production and irrigation. Its 135 MW (181,000 hp) power station produces an average of 287 gigawatt-hours (1,030 TJ) annually and water from the reservoir helps irrigate 69,500 hectares (172,000 acres) in the Beni Moussa and Tadla plains. (Full article...)
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).
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...)
In April 2019, Cinemax renewed the series for a second season which premiered on October 2, 2020. It was Cinemax's final series before ceasing production of original programming. In April 2021, the series was renewed for a third season, along with the announcement that the series would move to HBO Max, later rebranded to Max. The third season premiered on Max on June 29, 2023. In December 2023, the series was canceled after three seasons. (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...)
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...)
Jeet Kune Do (Chinese: 截拳道; "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.
The core of Jeet Kune Do is the interception of the opponent, making corresponding responses or counterattacks that strike at incoming attacks. 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...)
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...)
The 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, directed, written, produced by and starring Bruce Lee. The project was paused to film and produce Enter the Dragon. For The Game of Death, over 120 minutes of footage was shot, which was later misplaced in the Golden Harvest archives. 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...)
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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...)
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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...)
Chinese Gung Fu: The Philosophical Art of Self-Defense was published in early 1963 by Bruce Lee with the help of friend and fellow martial artist James Yimm Lee of Oakland, California. James had previously published books on the martial arts such as Modern Gung Fu, Karate: Iron, Poison Hand Training and Karate Oriental Self-Defense in 1957. In the book Remembering the Master: Bruce Lee, James Yimm Lee and the Creation of Jeet Kune Do by Sid Campbell and Greglon Yimm Lee (James Lee's son) it is stated the initial run was 1,500 copies. The book was sold through James Lee's company Oriental Book Sales at a price of $5. In addition to the book, a companion Chinese Gung Fu instruction chart was available for $1.
Following Bruce Lee's death, his estate commissioned writer John Little to edit and publish some of Lee's writings. Little included the content of Chinese Gung Fu: The Philosophical Art of Self-Defense as well as additional 1964 writings by Bruce Lee in the book Bruce Lee, The Tao of Gung Fu: Commentaries on the Chinese Martial Arts. (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.
The version of the film that is commonly distributed in the West (USA) on public domain-type DVD and video labels runs 93 minutes in length. The British VHS-version released in 1979 runs 118 minutes. (Full article...)
Bruce Lee: A Dragon Story also known as The Bruce Lee Story, Super Dragon: The Bruce Lee Story and Bruce Lee Story: Super Dragon) is a 1974 Bruceploitation film starring Bruce Li. The film is a loose biopic about martial arts actor Bruce Lee and centers on his supposed affair with actress Betty Ting-Pei. The film is notable for being the first biopic of Bruce Lee (it was released the year following his death), the debut film of notorious Lee imitator Bruce Li, and the first film in the Bruceploitation genre. (Full article...)
The version of the film that is commonly distributed in the West (USA) on public domain-type DVD and video labels runs 93 minutes in length. The British VHS-version released in 1979 runs 118 minutes. (Full article...)
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...)
The 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, directed, written, produced by and starring Bruce Lee. The project was paused to film and produce Enter the Dragon. For The Game of Death, over 120 minutes of footage was shot, which was later misplaced in the Golden Harvest archives. 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...)
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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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).
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 Lee Cadwell, 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...)
Chinese Gung Fu: The Philosophical Art of Self-Defense was published in early 1963 by Bruce Lee with the help of friend and fellow martial artist James Yimm Lee of Oakland, California. James had previously published books on the martial arts such as Modern Gung Fu, Karate: Iron, Poison Hand Training and Karate Oriental Self-Defense in 1957. In the book Remembering the Master: Bruce Lee, James Yimm Lee and the Creation of Jeet Kune Do by Sid Campbell and Greglon Yimm Lee (James Lee's son) it is stated the initial run was 1,500 copies. The book was sold through James Lee's company Oriental Book Sales at a price of $5. In addition to the book, a companion Chinese Gung Fu instruction chart was available for $1.
Following Bruce Lee's death, his estate commissioned writer John Little to edit and publish some of Lee's writings. Little included the content of Chinese Gung Fu: The Philosophical Art of Self-Defense as well as additional 1964 writings by Bruce Lee in the book Bruce Lee, The Tao of Gung Fu: Commentaries on the Chinese Martial Arts. (Full article...)
Outline of underwater diving § Modes of underwater diving[edit]
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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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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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Atmospheric diving suit
An atmospheric diving suit (ADS) 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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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.
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 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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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 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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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 anacronym 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 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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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 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 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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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 anacronym 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 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.
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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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 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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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 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 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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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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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 anacronym 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.
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 anacronym 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 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) 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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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 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 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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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.