|
Ecotone
An ecotone is a transitional area between two plant communities, where these meet and integrate. Examples include areas between grassland and forest, estuaries and lagoon, freshwater and sea water etc. An ecotone may be narrow or wide, and it may be local (the zone between a field and forest) or regional (the transition between forest and grassland ecosystems). An ecotone may appear on the ground as a gradual blending of the two communities across a broad area, or it may manifest itself as a sharp boundary line. Etymology The word ''ecotone'' was coined (and its etymology given) in 1904 in "The Development and Structure of Vegetation" (Lincoln, Nebraska: Botanical Seminar) by Frederic E. Clements. It is formed as a combination of ''ecology'' plus ''-tone'', from the Greek ''tonos'' or tension – in other words, a place where ecologies are in tension. Features There are several distinguishing features of an ecotone. First, an ecotone can have a sharp vegetation transition, wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Edge Effect
In ecology, edge effects are changes in population or community structures that occur at the boundary of two or more habitats. Areas with small habitat fragments exhibit especially pronounced edge effects that may extend throughout the range. As the edge effects increase, the boundary habitat allows for greater biodiversity. Urbanization is causing humans to continuously fragment landscapes and thus increase the edge effect. This change in landscape ecology is proving to have consequences. Generalist species, especially invasive ones, have been seen to benefit from this landscape change whilst specialist species are suffering. For example, the alpha diversity of edge-intolerant birds in Lacandona rainforest, Mexico, is decreasing as edge effects increase. Types * Inherent – Natural features stabilize the border location. * Induced – Transient natural disturbances (e.g., fire or flood) or human related activities, subject borders to successional changes over ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Land Clearing In Australia
Land clearing in Australia describes the removal of native vegetation and deforestation in Australia. Land clearing involves the removal of native vegetation and habitats, including the bulldozing of native bushlands, forests, savannah, woodlands and native grasslands and the draining of natural wetlands for replacement with Agriculture in Australia, agriculture, urban and other land uses. Much of today's clearing occurs in northern Australia. , of the vegetation which existed in Australia at the time of European settlement, approximately 87% remains. One estimate places the rate of rainforest of all types has been reduced by three quarters since the time of European settlement from eight million hectares to two million. Land clearing threatens native species including ground orchids and eucalyptus. Extensive unlawful deforestation continues across the country. Land clearing is an important Environmental issues in Australia, environmental issue in Australia. Bans on land cle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wetland
A wetland is a distinct semi-aquatic ecosystem whose groundcovers are flooded or saturated in water, either permanently, for years or decades, or only seasonally. Flooding results in oxygen-poor ( anoxic) processes taking place, especially in the soils. Wetlands form a transitional zone between waterbodies and dry lands, and are different from other terrestrial or aquatic ecosystems due to their vegetation's roots having adapted to oxygen-poor waterlogged soils. They are considered among the most biologically diverse of all ecosystems, serving as habitats to a wide range of aquatic and semi-aquatic plants and animals, with often improved water quality due to plant removal of excess nutrients such as nitrates and phosphorus. Wetlands exist on every continent, except Antarctica. The water in wetlands is either freshwater, brackish or saltwater. The main types of wetland are defined based on the dominant plants and the source of the water. For example, ''marshes'' ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mont Ventoux
Mont Ventoux (; ) is a mountain in the Provence region of southern France, located some northeast of Carpentras, Vaucluse. On the north side, the mountain borders the department of Drôme. At , it is the highest mountain in the region and has been nicknamed the "Beast of Provence", the "Giant of Provence", or "The Bald Mountain". It has gained fame through its inclusion in the Tour de France cycling race; in 2009 it was the scene of the first penultimate-day mountain top finish in the Tour de France, with Alberto Contador sealing his yellow jersey. As the name suggests (''venteux'' means windy in French), it can get windy at the summit, especially with the '' mistral''; wind speeds as high as have been recorded. The wind blows at over for 240 days a year. The road over the mountain is often closed due to high winds, especially the ''col des tempêtes'' ("storm pass") just before the summit, which is known for its strong winds. In the 10th century, the names ''Mons Vento ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blick Vom Löns Turm HemmelsdorferSee Ausfluss Aalbek
''Blick'' (View) is a Swiss German-language daily newspaper and online news website covering current affairs, entertainment, sports and lifestyle. Based in Zurich, it is the largest newspaper in Switzerland with a print circulation of around 285,000. The newspaper has been printed continuously since its inception in 1959. History and profile ''Blick'' was established in 1959. The newspaper was the first Swiss tabloid publication. The format of ''Blick'' was broadsheet until 2005 when it was switched to tabloid. The new format induced controversies: protests began and many boycotted the scandalous newspaper. It was nevertheless a huge financial success. However, in 2009 the daily changed its format to broadsheet. Its sister paper was from 2008–2018 '' Blick am Abend'', an evening free daily. Both papers are owned by Ringier and are based in Zürich. Ladina Heimgartner was appointed as CEO in October 2020. In August 2023, Christian Dorer stepped down as Editor-in-Chief after ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fauna
Fauna (: faunae or faunas) is all of the animal life present in a particular region or time. The corresponding terms for plants and fungi are ''flora'' and '' funga'', respectively. Flora, fauna, funga and other forms of life are collectively referred to as '' biota''. Zoologists and paleontologists use ''fauna'' to refer to a typical collection of animals found in a specific time or place, e.g. the " Sonoran Desert fauna" or the " Burgess Shale fauna". Paleontologists sometimes refer to a sequence of faunal stages, which is a series of rocks all containing similar fossils. The study of animals of a particular region is called faunistics. Etymology ''Fauna'' comes from the name Fauna, a Roman goddess of earth and fertility, the Roman god Faunus, and the related forest spirits called Fauns. All three words are cognates of the name of the Greek god Pan, and ''panis'' is the Modern Greek equivalent of fauna (πανίς or rather πανίδα). ''Fauna'' is also the word fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemocline
A chemocline is a type of cline, a layer of fluid with different properties, characterized by a strong, vertical chemistry gradient within a body of water. In bodies of water where chemoclines occur, the cline separates the upper and lower layers, resulting in different properties for those layers. The lower layer shows a change in the concentration of dissolved gases and solids compared to the upper layer. Chemoclines most commonly occur where local conditions favor the formation of anoxic bottom water — deep water deficient in oxygen, where only anaerobic forms of life can exist. Common anaerobic organisms that live in these conditions include phototrophic purple sulfur bacteria and green sulfur bacteria. The Black Sea is an example of a body of water with a prominent chemocline, though similar bodies (classified as meromictic lakes) exist across the globe. Meromictic lakes are the result of meromixis, which is a circumstance where a body of water does not fully mix and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermocline
A thermocline (also known as the thermal layer or the metalimnion in lakes) is a distinct layer based on temperature within a large body of fluid (e.g. water, as in an ocean or lake; or air, e.g. an atmosphere) with a high gradient of distinct temperature differences associated with depth. In the ocean, the thermocline divides the upper mixed layer from the calm deep water below. Depending largely on season, latitude, and turbulent mixing by wind, thermoclines may be a semi-permanent feature of the body of water in which they occur, or they may form temporarily in response to phenomena such as the radiative heating/cooling of surface water during the day/night. Factors that affect the depth and thickness of a thermocline include seasonal weather variations, latitude, and local environmental conditions, such as tides and currents. Oceans Most of the heat energy of the sunlight that strikes the Earth is absorbed in the first few centimeters at the ocean's surface, which hea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physical Chemistry
Physical chemistry is the study of macroscopic and microscopic phenomena in chemical systems in terms of the principles, practices, and concepts of physics such as motion, energy, force, time, thermodynamics, quantum chemistry, statistical mechanics, analytical dynamics and chemical equilibria. Physical chemistry, in contrast to chemical physics, is predominantly (but not always) a supra-molecular science, as the majority of the principles on which it was founded relate to the bulk rather than the molecular or atomic structure alone (for example, chemical equilibrium and colloids). Some of the relationships that physical chemistry strives to understand include the effects of: # Intermolecular forces that act upon the physical properties of materials ( plasticity, tensile strength, surface tension in liquids). # Reaction kinetics on the rate of a reaction. # The identity of ions and the electrical conductivity of materials. # Surface science and electrochemistry of cell m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrothermal
Hydrothermal circulation in its most general sense is the circulation of hot water (Ancient Greek ὕδωρ, ''water'',Liddell, H.G. & Scott, R. (1940). ''A Greek-English Lexicon. revised and augmented throughout by Sir Henry Stuart Jones. with the assistance of. Roderick McKenzie.'' Oxford: Clarendon Press. and θέρμη, ''heat'' ). Hydrothermal circulation occurs most often in the vicinity of sources of heat within the Earth's crust. In general, this occurs near volcanic activity, but can occur in the shallow to mid crust along deeply penetrating fault irregularities or in the deep crust related to the intrusion of granite, or as the result of orogeny or metamorphism. Hydrothermal circulation often results in hydrothermal mineral deposits. Seafloor hydrothermal circulation Hydrothermal circulation in the oceans is the passage of the water through mid-oceanic ridge systems. The term includes both the circulation of the well-known, high-temperature vent waters near the ridge c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gradient
In vector calculus, the gradient of a scalar-valued differentiable function f of several variables is the vector field (or vector-valued function) \nabla f whose value at a point p gives the direction and the rate of fastest increase. The gradient transforms like a vector under change of basis of the space of variables of f. If the gradient of a function is non-zero at a point p, the direction of the gradient is the direction in which the function increases most quickly from p, and the magnitude of the gradient is the rate of increase in that direction, the greatest absolute directional derivative. Further, a point where the gradient is the zero vector is known as a stationary point. The gradient thus plays a fundamental role in optimization theory, where it is used to minimize a function by gradient descent. In coordinate-free terms, the gradient of a function f(\mathbf) may be defined by: df=\nabla f \cdot d\mathbf where df is the total infinitesimal change in f for a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salinity
Salinity () is the saltiness or amount of salt (chemistry), salt dissolved in a body of water, called saline water (see also soil salinity). It is usually measured in g/L or g/kg (grams of salt per liter/kilogram of water; the latter is dimensionless and equal to per mille, ‰). Salinity is an important factor in determining many aspects of the chemistry of natural waters and of biological processes within it, and is a state function, thermodynamic state variable that, along with temperature and pressure, governs physical characteristics like the density and heat capacity of the water. A contour line of constant salinity is called an ''isohaline'', or sometimes ''isohale''. Definitions Salinity in rivers, lakes, and the ocean is conceptually simple, but technically challenging to define and measure precisely. Conceptually the salinity is the quantity of dissolved salt content of the water. Salts are compounds like sodium chloride, magnesium sulfate, potassium nitrate, and sod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
