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Scientific Echosounder
A scientific echosounder is a device which uses sonar technology for the measurement of underwater physical and biological components—this device is also known as ''scientific sonar''. Applications include bathymetry, seabed, substrate classification, studies of Alga, aquatic vegetation, fish, and plankton, and differentation of water masses. Technology Scientific echosounder equipment is built to exacting standards and tested to be stable and reliable in the transmission and receiving of sound energy under the water. Recent advances have led to the development of the digital scientific echosounder, further enhancing the reliability and precision with which these systems operate. Modern scientific echosounders are reliable, portable, and relatively easy to use. Collected acoustic data is "stamped" with geographic information for precise positional information (coordinates and time). This enables analysis and incorporation of the results into a Geographic Information Syste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sonar
Sonar (sound navigation and ranging or sonic navigation and ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigation, navigate, measure distances (ranging), communicate with or detect objects on or under the surface of the water, such as other vessels. "Sonar" can refer to one of two types of technology: ''passive'' sonar means listening for the sound made by vessels; ''active'' sonar means emitting pulses of sounds and listening for echoes. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water. Acoustic location in air was used before the introduction of radar. Sonar may also be used for robot navigation, and SODAR (an upward-looking in-air sonar) is used for atmospheric investigations. The term ''sonar'' is also used for the equipment used to generate and receive the sound. The acoustic frequencies used in sonar systems vary from very low (infrasonic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transducer
A transducer is a device that converts energy from one form to another. Usually a transducer converts a signal in one form of energy to a signal in another. Transducers are often employed at the boundaries of automation, measurement, and control systems, where electrical signals are converted to and from other physical quantities (energy, force, torque, light, motion, position, etc.). The process of converting one form of energy to another is known as transduction. Types * Mechanical transducers, so-called as they convert physical quantities into mechanical outputs or vice versa; * Electrical transducers however convert physical quantities into electrical outputs or signals. Examples of these are: ** a thermocouple that changes temperature differences into a small voltage; ** a linear variable differential transformer (LVDT), used to measure displacement (position) changes by means of electrical signals. Sensors, actuators and transceivers Transducers can be categorized by wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Council For The Exploration Of The Sea
The International Council for the Exploration of the Sea (ICES; french: Conseil International de l'Exploration de la Mer, ''CIEM'') is a regional fishery advisory body and the world's oldest intergovernmental science organization. ICES is headquartered in Copenhagen, Denmark, where its multinational secretariat staff of 51 provide scientific, administrative and secretarial support to the ICES community. It was established on July 22, 1902, in Copenhagen. Functions ICES is a leading multidisciplinary scientific forum for the exchange of information and ideas on all aspects of marine sciences pertaining to the North Atlantic, including the adjacent Baltic Sea and North Sea, and for the promotion and coordination of marine research by scientists within its member nations. Its principal functions, both when it was established and continuing to the present time, are to: (i) promote, encourage, develop, and coordinate marine research; (ii) publish and otherwise disseminate results of r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fisheries Management
The goal of fisheries management is to produce sustainable biological, environmental and socioeconomic benefits from renewable aquatic resources. Wild fisheries are classified as renewable when the organisms of interest (e.g., fish, shellfish, amphibians, reptiles and marine mammals) produce an annual biological surplus that with judicious management can be harvested without reducing future productivity. Fishery management employs activities that protect fishery resources so sustainable exploitation is possible, drawing on fisheries science and possibly including the precautionary principle. Modern fisheries management is often referred to as a governmental system of appropriate environmental management rules based on defined objectives and a mix of management means to implement the rules, which are put in place by a system of monitoring control and surveillance. A popular approach is the ecosystem approach to fisheries management. According to the Food and Agriculture Organi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Submersed Aquatic Vegetation
Aquatic plants are plants that have adapted to living in aquatic environments (saltwater or freshwater). They are also referred to as hydrophytes or macrophytes to distinguish them from algae and other microphytes. A macrophyte is a plant that grows in or near water and is either emergent, submergent, or floating. In lakes and rivers macrophytes provide cover for fish, substrate for aquatic invertebrates, produce oxygen, and act as food for some fish and wildlife. Macrophytes are primary producers and are the basis of the food web for many organisms. They have a significant effect on soil chemistry and light levels as they slow down the flow of water and capture pollutants and trap sediments. Excess sediment will settle into the benthos aided by the reduction of flow rates caused by the presence of plant stems, leaves and roots. Some plants have the capability of absorbing pollutants into their tissue. Seaweeds are multicellular marine algae and, although their ecological i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biomass
Biomass is plant-based material used as a fuel for heat or electricity production. It can be in the form of wood, wood residues, energy crops, agricultural residues, and waste from industry, farms, and households. Some people use the terms biomass and biofuel interchangeably, while others consider biofuel to be a ''liquid'' or ''gaseous'' fuel used for transportation, as defined by government authorities in the US and EU. The European Union's Joint Research Centre defines solid biofuel as raw or processed organic matter of biological origin used for energy, such as firewood, wood chips, and wood pellets. In 2019, biomass was used to produce 57 EJ (exajoules) of energy, compared to 190 EJ from crude oil, 168 EJ from coal, 144 EJ from natural gas, 30 EJ from nuclear, 15 EJ from hydro and 13 EJ from wind, solar and geothermal combined. Approximately 86% of modern bioenergy is used for heating applications, with 9% used for transport and 5% for electricity. Most of the global b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sediment
Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand and silt can be carried in suspension in river water and on reaching the sea bed deposited by sedimentation; if buried, they may eventually become sandstone and siltstone (sedimentary rocks) through lithification. Sediments are most often transported by water (fluvial processes), but also wind (aeolian processes) and glaciers. Beach sands and river channel deposits are examples of fluvial transport and deposition, though sediment also often settles out of slow-moving or standing water in lakes and oceans. Desert sand dunes and loess are examples of aeolian transport and deposition. Glacial moraine deposits and till are ice-transported sediments. Classification Sediment can be classified based on its grain size, grain shape, and c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seabed
The seabed (also known as the seafloor, sea floor, ocean floor, and ocean bottom) is the bottom of the ocean. All floors of the ocean are known as 'seabeds'. The structure of the seabed of the global ocean is governed by plate tectonics. Most of the ocean is very deep, where the seabed is known as the abyssal plain. Seafloor spreading creates mid-ocean ridges along the center line of major ocean basins, where the seabed is slightly shallower than the surrounding abyssal plain. From the abyssal plain, the seabed slopes upward toward the continents and becomes, in order from deep to shallow, the continental rise, slope, and shelf. The depth within the seabed itself, such as the depth down through a sediment core, is known as the “depth below seafloor.” The ecological environment of the seabed and the deepest waters are collectively known, as a habitat for creatures, as the “benthos.” Most of the seabed throughout the world's oceans is covered in layers of marine sediments. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bathymetry
Bathymetry (; ) is the study of underwater depth of ocean floors (''seabed topography''), lake floors, or river floors. In other words, bathymetry is the underwater equivalent to hypsometry or topography. The first recorded evidence of water depth measurements are from Ancient Egypt over 3000 years ago. Bathymetric (or hydrographic) charts are typically produced to support safety of surface or sub-surface navigation, and usually show seafloor relief or terrain as contour lines (called depth contours or isobaths) and selected depths ('' soundings''), and typically also provide surface navigational information. Bathymetric maps (a more general term where navigational safety is not a concern) may also use a Digital Terrain Model and artificial illumination techniques to illustrate the depths being portrayed. The global bathymetry is sometimes combined with topography data to yield a global relief model. Paleobathymetry is the study of past underwater depths. Seabed topography ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bathymetry
Bathymetry (; ) is the study of underwater depth of ocean floors (''seabed topography''), lake floors, or river floors. In other words, bathymetry is the underwater equivalent to hypsometry or topography. The first recorded evidence of water depth measurements are from Ancient Egypt over 3000 years ago. Bathymetric (or hydrographic) charts are typically produced to support safety of surface or sub-surface navigation, and usually show seafloor relief or terrain as contour lines (called depth contours or isobaths) and selected depths ('' soundings''), and typically also provide surface navigational information. Bathymetric maps (a more general term where navigational safety is not a concern) may also use a Digital Terrain Model and artificial illumination techniques to illustrate the depths being portrayed. The global bathymetry is sometimes combined with topography data to yield a global relief model. Paleobathymetry is the study of past underwater depths. Seabed topography ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geographic Information System
A geographic information system (GIS) is a type of database containing Geographic data and information, geographic data (that is, descriptions of phenomena for which location is relevant), combined with Geographic information system software, software tools for managing, Spatial analysis, analyzing, and Cartographic design, visualizing those data. In a broader sense, one may consider such a system to also include human users and support staff, procedures and workflows, body of knowledge of relevant concepts and methods, and institutional organizations. The uncounted plural, ''geographic information systems'', also abbreviated GIS, is the most common term for the industry and profession concerned with these systems. It is roughly synonymous with geoinformatics and part of the broader geospatial field, which also includes GPS, remote sensing, etc. Geographic information science, the academic discipline that studies these systems and their underlying geographic principles, may also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Scientific Echosounder
A scientific echosounder is a device which uses sonar technology for the measurement of underwater physical and biological components—this device is also known as ''scientific sonar''. Applications include bathymetry, substrate classification, studies of aquatic vegetation, fish, and plankton, and differentation of water masses. Technology Scientific echosounder equipment is built to exacting standards and tested to be stable and reliable in the transmission and receiving of sound energy under the water. Recent advances have led to the development of the digital scientific echosounder, further enhancing the reliability and precision with which these systems operate. Modern scientific echosounders are reliable, portable, and relatively easy to use. Collected acoustic data is "stamped" with geographic information for precise positional information (coordinates and time). This enables analysis and incorporation of the results into a Geographic Information System (GIS) for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
