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Underwater Logging
Underwater logging is the process of logging trees from underwater forests. When artificial reservoirs and dams are built, large areas of forest are often inundated; although the trees die, the wood is often preserved. The trees can then be felled using special underwater machinery and floated up to the surface. One such machine is the sawfish harvester. There is an ongoing debate to determine whether or not underwater logging is a sustainable practice and if it is more environmentally sustainable than traditional logging. Underwater logging has been introduced in select locations around the world, including Ghana's Lake Volta, the largest reservoir by surface area in the world. A related form of logging consists of salvaging logs which loggers have abandoned after they became waterlogged and sank. This activity can be quite profitable, since the prime "targets" are decades-old trees of a size and species difficult or impossible to find in their natural habitat. History In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Logging
Logging is the process of cutting, processing, and moving trees to a location for transport. It may include skidding, on-site processing, and loading of trees or logs onto trucks or skeleton cars. Logging is the beginning of a supply chain that provides raw material for many products societies worldwide use for housing, construction, energy, and consumer paper products. Logging systems are also used to manage forests, reduce the risk of wildfires, and restore ecosystem functions, though their efficiency for these purposes has been challenged. In forestry, the term logging is sometimes used narrowly to describe the logistics of moving wood from the stump to somewhere outside the forest, usually a sawmill or a lumber yard. In common usage, however, the term may cover a range of forestry or silviculture activities. Illegal logging refers to the harvesting, transportation, purchase, or sale of timber in violation of laws. The harvesting procedure itself may be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reservoir
A reservoir (; from French ''réservoir'' ) is an enlarged lake behind a dam. Such a dam may be either artificial, built to store fresh water or it may be a natural formation. Reservoirs can be created in a number of ways, including controlling a watercourse that drains an existing body of water, interrupting a watercourse to form an embayment within it, through excavation, or building any number of retaining walls or levees. In other contexts, "reservoirs" may refer to storage spaces for various fluids; they may hold liquids or gasses, including hydrocarbons. ''Tank reservoirs'' store these in ground-level, elevated, or buried tanks. Tank reservoirs for water are also called cisterns. Most underground reservoirs are used to store liquids, principally either water or petroleum. Types Dammed valleys Dammed reservoirs are artificial lakes created and controlled by a dam constructed across a valley, and rely on the natural topography to provide most of the basin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Felling
Felling is the process of cutting down trees,"Feller" def. 2. and "Felling", def. 1. ''Oxford English Dictionary'' Second Edition on CD-ROM (v. 4.0) © Oxford University Press 2009 an element of the task of logging Logging is the process of cutting, processing, and moving trees to a location for transport. It may include skidding, on-site processing, and loading of trees or logs onto trucks or skeleton cars. Logging is the beginning of a supply chain .... The person cutting the trees is a ''feller''. A feller buncher is a machine capable of felling a single large tree or grouping and felling several small ones simultaneously. Methods Hand felling In hand felling, an axe, saw, or chainsaw is used to fell a tree, followed up by limbing and bucking in traditional applications. In the modern commercial logging industry, felling is typically followed by limbing and skidding. Feller buncher A feller-buncher is a motorized vehicle with an attachment which rapidly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sawfish Harvester
The Sawfish harvester is a submersible robot produced by the Triton Logging Inc. It is designed for cutting down submerged trees and popping them to the surface, with large pincers and a chainsaw A chainsaw (or chain saw) is a portable gasoline-, electric-, or battery-powered saw that cuts with a set of teeth attached to a rotating chain driven along a guide bar. It is used in activities such as tree felling, limbing, Log bucking, bucki .... Such trees are generally submerged when dams are built near existing forests, and their wood remains good while underwater for long periods. External links News reporton the Sawfish Triton Engineering page: details on the Sawfish Underwater robots 2000s robots Robots of Canada {{product-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake Volta
Lake Volta, the largest artificial reservoir in the world based on surface area, is contained behind the Akosombo Dam which generates a substantial amount of Ghana's electricity. It is completely within the country of Ghana and has a surface area of . It extends from Akosombo in the south to the northern part of the country. Geography Lake Volta lies along the Prime meridian, and just six degrees of latitude north of the Equator. The lake's northernmost point is close to the town of Yapei, and its southernmost extreme is at the Akosombo Dam, downstream from Yapei. Akosombo Dam holds back both the White Volta River and the Black Volta River, which formerly converged where the middle of the reservoir now lies, to form the single Volta River. The present Volta River flows from the outlets of the dam's powerhouse and spillways to the Atlantic Ocean in southern Ghana. The main islands within the lake are Dodi, Dwarf, and Kporve. Digya National Park lies on part of the lake's weste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Great Lakes
The Great Lakes, also called the Great Lakes of North America, are a series of large interconnected freshwater lakes in the mid-east region of North America that connect to the Atlantic Ocean via the Saint Lawrence River. There are five lakes, which are Superior, Michigan, Huron, Erie, and Ontario and are in general on or near the Canada–United States border. Hydrologically, lakes Michigan and Huron are a single body joined at the Straits of Mackinac. The Great Lakes Waterway enables modern travel and shipping by water among the lakes. The Great Lakes are the largest group of freshwater lakes on Earth by total area and are second-largest by total volume, containing 21% of the world's surface fresh water by volume. The total surface is , and the total volume (measured at the low water datum) is , slightly less than the volume of Lake Baikal (, 22–23% of the world's surface fresh water). Because of their sea-like characteristics, such as rolling waves, sustained w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maine
Maine () is a U.S. state, state in the New England and Northeastern United States, Northeastern regions of the United States. It borders New Hampshire to the west, the Gulf of Maine to the southeast, and the Provinces and territories of Canada, Canadian provinces of New Brunswick and Quebec to the northeast and northwest, respectively. The largest state by total area in New England, Maine is the List of U.S. states and territories by area, 12th-smallest by area, the List of U.S. states and territories by population, 9th-least populous, the List of U.S. states by population density, 13th-least densely populated, and the most rural of the List of states and territories of the United States, 50 U.S. states. It is also the northeastern United States, northeasternmost among the contiguous United States, the northernmost state east of the Great Lakes, the only state whose name consists of a single syllable, and the only state to border exactly one other U.S. state. Approximately half ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Penobscot River
The Penobscot River ( Abenaki: ''Pαnawάhpskewtəkʷ'') is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map, accessed June 22, 2011 river in the U.S. state of Maine. Including the river's West Branch and South Branch increases the Penobscot's length to , making it the second-longest river system in Maine and the longest entirely in the state. Its drainage basin contains . It arises from four branches in several lakes in north-central Maine, which flow generally east. After the uniting of the West Branch with the East Branch at Medway (), the Penobscot flows south, past the city of Bangor, where it becomes navigable. Also at Bangor is the tributary Kenduskeag Stream. It empties into the Atlantic Ocean in Penobscot Bay. It is home to the Penobscot people that live on Indian Island, and considered to be The People's lifeblood. History Norumbega Most historians have accepted the Penobscot region as Jean Allefonsce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Remotely Operated Underwater Vehicle
A remotely operated underwater vehicle (technically ROUV or just ROV) is a tethered underwater mobile device, commonly called ''underwater robot''. Definition This meaning is different from remote control vehicles operating on land or in the air. ROVs are unoccupied, usually highly maneuverable, and operated by a crew either aboard a vessel/floating platform or on proximate land. They are common in deepwater industries such as offshore hydrocarbon extraction. They are linked to a host ship by a neutrally buoyant tether or, often when working in rough conditions or in deeper water, a load-carrying umbilical cable is used along with a tether management system (TMS). The TMS is either a garage-like device which contains the ROV during lowering through the splash zone or, on larger work-class ROVs, a separate assembly which sits on top of the ROV. The purpose of the TMS is to lengthen and shorten the tether so the effect of cable drag where there are underwater currents is minim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Logging
Logging is the process of cutting, processing, and moving trees to a location for transport. It may include skidding, on-site processing, and loading of trees or logs onto trucks or skeleton cars. Logging is the beginning of a supply chain that provides raw material for many products societies worldwide use for housing, construction, energy, and consumer paper products. Logging systems are also used to manage forests, reduce the risk of wildfires, and restore ecosystem functions, though their efficiency for these purposes has been challenged. In forestry, the term logging is sometimes used narrowly to describe the logistics of moving wood from the stump to somewhere outside the forest, usually a sawmill or a lumber yard. In common usage, however, the term may cover a range of forestry or silviculture activities. Illegal logging refers to the harvesting, transportation, purchase, or sale of timber in violation of laws. The harvesting procedure itself may be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake Erie Erosion -- USGS
A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much larger oceans, they do form part of the Earth's water cycle. Lakes are distinct from lagoons, which are generally coastal parts of the ocean. Lakes are typically larger and deeper than ponds, which also lie on land, though there are no official or scientific definitions. Lakes can be contrasted with rivers or streams, which usually flow in a channel on land. Most lakes are fed and drained by rivers and streams. Natural lakes are generally found in mountainous areas, rift zones, and areas with ongoing glaciation. Other lakes are found in endorheic basins or along the courses of mature rivers, where a river channel has widened into a basin. Some parts of the world have many lakes formed by the chaotic drainage patterns left over from the last ice ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ecosystem
An ecosystem (or ecological system) consists of all the organisms and the physical environment with which they interact. These biotic and abiotic components are linked together through nutrient cycles and energy flows. Energy enters the system through photosynthesis and is incorporated into plant tissue. By feeding on plants and on one another, animals play an important role in the movement of matter and energy through the system. They also influence the quantity of plant and microbial biomass present. By breaking down dead organic matter, decomposers release carbon back to the atmosphere and facilitate nutrient cycling by converting nutrients stored in dead biomass back to a form that can be readily used by plants and microbes. Ecosystems are controlled by external and internal factors. External factors such as climate, parent material which forms the soil and topography, control the overall structure of an ecosystem but are not themselves influenced by the ecosyst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
