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Lowland Football League Managers
Upland and lowland are conditional descriptions of a plain based on elevation above sea level. In studies of the ecology of freshwater rivers, habitats are classified as upland or lowland. Definitions Upland and lowland are portions of a plain that are conditionally categorized by their elevation above the sea level. Lowlands are usually no higher than , while uplands are somewhere around to . On unusual occasions, certain lowlands such as the Caspian Depression lie below sea level. Uplands areas tend to spike into valleys and mountains, forming mountain ranges while lowland areas tend to be uniformly flat, although both can vary such as the Mongolian Plateau. Upland habitats are cold, clear and rocky whose rivers are fast-flowing in mountainous areas; lowland habitats are warm with slow-flowing rivers found in relatively flat lowland areas, with water that is frequently colored by sediment and organic matter. These classifications overlap with the geological definitions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cascadilla Creek
Cascadilla Creek is a river located in Tompkins County, New York. It flows into Cayuga Inlet by Ithaca, New York. Gallery File:CascadillaCreekSign.jpg File:CascadillaGlenTrail.jpg File:CascadillaCreekFalls1.jpg File:CascadillaCreekFalls2.jpg File:CascadillaCreekFalls3.jpg File:CascadillaCreekFalls5.jpg File:CascadillaCreekFalls4.jpg File:CascadillaCreek5.jpg File:CascadillaCreek6.jpg File:CascadillaCreek7.jpg References {{authority control Rivers of Tompkins County, New York Rivers of New York (state) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alluvial Plain
An alluvial plain is a plain (an essentially flat landform) created by the deposition of sediment over a long period by one or more rivers coming from highland regions, from which alluvial soil forms. A ''floodplain'' is part of the process, being the smaller area over which the rivers flood at a particular time. In contrast, the alluvial plain is the larger area representing the region over which the floodplains have shifted over geological time. As the highlands erode due to weathering and water flow, the sediment from the hills is transported to the lower plain. Various creeks will carry the water further to a river, lake, bay, or ocean. As the sediments are deposited during flood conditions in the floodplain of a creek, the elevation of the floodplain will be raised. As this reduces the channel floodwater capacity, the creek will, over time, seek new, lower paths, forming a meander (a curved path). The leftover higher locations, typically natural levees at the margins of ... [...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] |
Water Clarity
Water clarity is a descriptive term for how deeply visible light penetrates through water. In addition to light penetration, the term water clarity is also often used to describe underwater visibility. Water clarity is one way that humans measure water quality, along with oxygen concentration and the presence or absence of pollutants and algal blooms. Water clarity governs the health of underwater ecosystems because it impacts the amount of light reaching the plants and animals living underwater. For plants, light is needed for photosynthesis. The clarity of the underwater environment determines the depth ranges where aquatic plants can live. Water clarity also impacts how well visual animals like fish can see their prey. Clarity affects the aquatic plants and animals living in all kinds of water bodies, including rivers, ponds, lakes, reservoirs, estuaries, coastal lagoons, and the open ocean. Water clarity also affects how humans interact with water, from recreation and propert ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rapids
Rapids are sections of a river where the river bed has a relatively steep stream gradient, gradient, causing an increase in water velocity and turbulence. Flow, gradient, constriction, and obstacles are four factors that are needed for a rapid to be created. Physical factors Rapids are hydrology, hydrological features between a ''run'' (a smoothly flowing part of a stream) and a ''waterfall#Types, cascade''. Rapids are characterized by the river becoming shallower with some Rock (geology), rocks exposed above the flow surface. As flowing water splashes over and around the rocks, air bubbles become mixed in with it and portions of the surface acquire a white color, forming what is called "whitewater". Rapids occur where the stream bed, bed material is highly resistant to the erosive power of the stream in comparison with the bed downstream of the rapids. Very young streams flowing across solid rock may be rapids for much of their length. Rapids cause water aeration of the stream ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Riffle
A riffle is a shallow landform in a flowing channel. Colloquially, it is a shallow place in a river where water flows quickly past rocks. However, in geology a riffle has specific characteristics. Topographic, sedimentary and hydraulic indicators Riffles are almost always found to have a very low discharge compared to the flow that fills the channel (approximately 10–20%), and as a result the water moving over a riffle appears shallow and fast, with a wavy, disturbed water surface. The water's surface over a riffle at low flow also has a much steeper slope than that over other in-channel landforms. Channel sections with a mean water surface slope of roughly 0.1 to 0.5% exhibit riffles, though they can occur in steeper or gentler sloping channels with coarser or finer bed materials, respectively. Except in the period after a flood (when fresh material is deposited on a riffle), the sediment on the riverbed in a riffle is usually much coarser than on that in any other in-chan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bedrock
In geology, bedrock is solid rock that lies under loose material ( regolith) within the crust of Earth or another terrestrial planet. Definition Bedrock is the solid rock that underlies looser surface material. An exposed portion of bedrock is often called an outcrop. The various kinds of broken and weathered rock material, such as soil and subsoil, that may overlie the bedrock are known as regolith. Engineering geology The surface of the bedrock beneath the soil cover (regolith) is also known as ''rockhead'' in engineering geology, and its identification by digging, drilling or geophysical methods is an important task in most civil engineering projects. Superficial deposits can be very thick, such that the bedrock lies hundreds of meters below the surface. Weathering of bedrock Exposed bedrock experiences weathering, which may be physical or chemical, and which alters the structure of the rock to leave it susceptible to erosion. Bedrock may also experience subsur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
River Bed
A streambed or stream bed is the bottom of a stream or river and is confined within a channel or the banks of the waterway. Usually, the bed does not contain terrestrial (land) vegetation and instead supports different types of aquatic vegetation (aquatic plant), depending on the type of streambed material and water velocity. Streambeds are what would be left once a stream is no longer in existence. The beds are usually well preserved even if they get buried because the banks and canyons made by the stream are typically hard, although soft sand and debris often fill the bed. Dry, buried streambeds can actually be underground water pockets. During times of rain, sandy streambeds can soak up and retain water, even during dry seasons, keeping the water table close enough to the surface to be obtainable by local people. The nature of any streambed is always a function of the flow dynamics and the local geologic materials. The climate of an area will determine the amount of precip ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Incised Course
Incision may refer to: * Cutting Cutting is the separation or opening of a physical object, into two or more portions, through the application of an acutely directed force. Implements commonly used for wikt:cut, cutting are the knife and saw, or in medicine and science the sca ..., the separation of an object, into two or more portions, through the application of an acutely directed force * A type of open wound caused by a clean, sharp-edged object such as a knife, razor, or glass splinter * Surgical incision, a cut made through the skin and soft tissue to facilitate an operation or procedure * River incision, in geomorphology * ''Incisions'' (album), by American deathcore band Oceano * Incision (band), a Dutch hard rock band * Incision (G.I. Joe), a fictional character {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stream Gradient
Stream gradient (or stream slope) is the grade (or slope) of a stream. It is measured by the ratio of drop in elevation and horizontal distance. It is a dimensionless quantity, usually expressed in units of meters per kilometer (m/km) or feet per mile (ft/mi); it may also be expressed in percent (%). The world average river reach slope is 2.6 m/km or 0.26%; a slope smaller than 1% and greater than 4% is considered gentle and steep, respectively. Stream gradient may change along the stream course. An average gradient can be defined, known as the relief ratio, which gives the average drop in elevation per unit length of river. The calculation is the difference in elevation between the river's source and the river terminus (confluence or mouth) divided by the total length of the river or stream. Hydrology and geology A high gradient indicates a steep slope and rapid flow of water (i.e. more ability to erode); where as a low gradient indicates a more nearly level stream bed and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stream Power
Stream power, originally derived by Ralph Bagnold, R. A. Bagnold in the 1960s, is the amount of energy the water in a river or stream is exerting on the sides and bottom of the river. Stream power is the result of multiplying the density of the water, the acceleration of the water due to gravity, the volume of water flowing through the river, and the slope of that water. There are many forms of the stream power formula with varying utilities, such as comparing rivers of various widths or quantifying the energy required to move sediment of a certain size. Stream power is closely related to other criteria such as stream competency and shear stress. Stream power is a valuable measurement for Hydrology, hydrologists and Geomorphology, geomorphologists tackling sediment transport issues as well as for Civil engineering, civil engineers, who use it in the planning and construction of roads, bridges, dams, and culverts. History Although many authors had suggested the use of power formul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
