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Floodplain
A floodplain or flood plain or bottomlands is an area of land adjacent to a river. Floodplains stretch from the banks of a river channel to the base of the enclosing valley, and experience flooding during periods of high Discharge (hydrology), discharge.Goudie, A. S., 2004, ''Encyclopedia of Geomorphology'', vol. 1. Routledge, New York. The soils usually consist of clays, silts, sands, and gravels deposited during floods. Because of regular flooding, floodplains frequently have high soil fertility since nutrients are deposited with the flood waters. This can encourage farming; some important agricultural regions, such as the Nile and Mississippi Basin, Mississippi Drainage basin, river basins, heavily exploit floodplains. Agricultural and urban regions have developed near or on floodplains to take advantage of the rich soil and freshwater. However, the Flood risk, risk of inundation has led to increasing efforts to Flood control, control flooding. Formation Most floodplai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flood Plain 7991
A flood is an overflow of water ( or rarely other fluids) that submerges land that is usually dry. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Floods are of significant concern in agriculture, civil engineering and public health. Human changes to the environment often increase the intensity and frequency of flooding. Examples for human changes are land use changes such as deforestation and removal of wetlands, changes in waterway course or flood controls such as with levees. Global environmental issues also influence causes of floods, namely climate change which causes an intensification of the water cycle and sea level rise. For example, climate change makes extreme weather events more frequent and stronger. This leads to more intense floods and increased flood risk. Natural types of floods include river flooding, groundwater flooding coastal flooding and urban flooding sometimes known as flash flooding. Tidal flooding may incl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flood
A flood is an overflow of water (list of non-water floods, or rarely other fluids) that submerges land that is usually dry. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Floods are of significant concern in agriculture, civil engineering and public health. Environmental issues, Human changes to the environment often increase the intensity and frequency of flooding. Examples for human changes are land use changes such as deforestation and Wetland conservation, removal of wetlands, changes in waterway course or flood controls such as with levees. Global environmental issues also influence causes of floods, namely climate change which causes an Effects of climate change on the water cycle, intensification of the water cycle and sea level rise. For example, climate change makes Extreme weather, extreme weather events more frequent and stronger. This leads to more intense floods and increased flood risk. Natural types of floods include riv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flood Risk
A flood is an overflow of water ( or rarely other fluids) that submerges land that is usually dry. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Floods are of significant concern in agriculture, civil engineering and public health. Human changes to the environment often increase the intensity and frequency of flooding. Examples for human changes are land use changes such as deforestation and removal of wetlands, changes in waterway course or flood controls such as with levees. Global environmental issues also influence causes of floods, namely climate change which causes an intensification of the water cycle and sea level rise. For example, climate change makes extreme weather events more frequent and stronger. This leads to more intense floods and increased flood risk. Natural types of floods include river flooding, groundwater flooding coastal flooding and urban flooding sometimes known as flash flooding. Tidal flooding may incl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluvial Terrace
Fluvial terraces are elongated Terrace (geology), terraces that flank the sides of floodplains and fluvial valleys all over the world. They consist of a relatively level strip of land, called a "tread", separated from either an adjacent floodplain, other fluvial terraces, or uplands by distinctly steeper strips of land called "risers". These terraces lie parallel to and above the river channel and its floodplain. Because of the manner in which they form, fluvial terraces are underlain by fluvial sediments of highly variable thickness. River terraces are the remnants of earlier floodplains that existed at a time when either a stream or river was flowing at a higher elevation before its channel downcut to create a new floodplain at a lower elevation. Changes in elevation can be due to changes in the base level (elevation of the lowest point in the fluvial system, usually the drainage basin) of the fluvial system, which leads to headward erosion along the length of either a stream or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
River
A river is a natural stream of fresh water that flows on land or inside Subterranean river, caves towards another body of water at a lower elevation, such as an ocean, lake, or another river. A river may run dry before reaching the end of its course if it runs out of water, or only flow during certain seasons. Rivers are regulated by the water cycle, the processes by which water moves around the Earth. Water first enters rivers through precipitation, whether from rainfall, the Runoff (hydrology), runoff of water down a slope, the melting of glaciers or snow, or seepage from aquifers beneath the surface of the Earth. Rivers flow in channeled watercourses and merge in confluences to form drainage basins, or catchments, areas where surface water eventually flows to a common outlet. Rivers have a great effect on the landscape around them. They may regularly overflow their Bank (geography), banks and flood the surrounding area, spreading nutrients to the surrounding area. Sedime ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meanders
A meander is one of a series of regular sinuous curves in the channel of a river or other watercourse. It is produced as a watercourse erodes the sediments of an outer, concave bank ( cut bank or river cliff) and deposits sediments on an inner, convex bank which is typically a point bar. The result of this coupled erosion and sedimentation is the formation of a sinuous course as the channel migrates back and forth across the axis of a floodplain. The zone within which a meandering stream periodically shifts its channel is known as a meander belt. It typically ranges from 15 to 18 times the width of the channel. Over time, meanders migrate downstream, sometimes in such a short time as to create civil engineering challenges for local municipalities attempting to maintain stable roads and bridges.Neuendorf, K.K.E., J.P. Mehl Jr., and J.A. Jackson, J.A., eds. (2005) ''Glossary of Geology'' (5th ed.). Alexandria, Virginia, American Geological Institute. 779 pp. Charlton, R., 200 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flood Control
Flood management or flood control are methods used to reduce or prevent the detrimental effects of flood waters. Flooding can be caused by a mix of both natural processes, such as extreme weather upstream, and human changes to waterbodies and runoff. Flood management methods can be either of the ''structural'' type (i.e. flood control) and of the ''non-structural'' type. Structural methods hold back floodwaters physically, while non-structural methods do not. Building hard infrastructure to prevent flooding, such as flood walls, is effective at managing flooding. However, it is best practice within landscape engineering to rely more on soft infrastructure and Nature-based solutions, natural systems, such as marshes and Floodplain, flood plains, for handling the increase in water. Flood management can include ''flood risk management,'' which focuses on measures to reduce risk, vulnerability and exposure to flood disasters and providing risk analysis through, for example, flood ris ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
River Incision
River incision is the narrow erosion caused by a river or stream that is far from its base level. River incision is common after tectonic uplift of the landscape. Incision by multiple rivers result in a dissected landscape, for example a dissected plateau. River incision is the natural process by which a river cuts downward into its bed, deepening the active channel. Though it is a natural process, it can be accelerated rapidly by human factors including land use changes such as timber harvest, mining, agriculture, and road and dam construction. The rate of incision is a function of basal shear-stress. Shear stress is increased by factors such as sediment in the water, which increase its density. Sediment transport#Depth-slope product, Shear stress t is proportional to water mass, gravity, and WSS: ::t = \rho gD\sin where t is shear stress (N/m2), ρ is density of flowing water, g is gravity on Earth, D is average water depth, and WSS is Water Surface Slope. This is analogous to t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crevasse Splay
A crevasse splay is a sedimentary fluvial deposit which forms when a stream breaks its natural or artificial levees and deposits sediment on a floodplain. A breach that forms a crevasse splay deposits sediments in similar pattern to an alluvial fan deposit. Once the levee has been breached the water flows out of its channel. As the water spreads onto the flood plain sediments will start to fall out of suspension as the water loses energy. The resulting deposition can create graded deposits similar to those found in Bouma sequences. In some cases crevasse splays can cause a river to abandon its old river channel, a process known as avulsion. Breaches that form a crevasse splay deposits occur most commonly on the outside banks of meander A meander is one of a series of regular sinuous curves in the Channel (geography), channel of a river or other watercourse. It is produced as a watercourse erosion, erodes the sediments of an outer, concave bank (cut bank, cut bank or river ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aggradation
Aggradation (or alluviation) is the term used in geology for the increase in land elevation, typically in a river system, due to the deposition of sediment. Aggradation occurs in areas in which the supply of sediment is greater than the amount of material that the system is able to transport. The mass balance between sediment being transported and sediment in the bed is described by the Exner equation. Typical aggradational environments include lowland alluvial rivers, river deltas, and alluvial fans. Aggradational environments are often undergoing slow subsidence which balances the increase in land surface elevation due to aggradation. After millions of years, an aggradational environment will become a sedimentary basin, which contains the deposited sediment, including paleochannels and ancient floodplains. Aggradation can be caused by changes in climate, land use, and geologic activity, such as volcanic eruption, earthquake An earthquakealso called a quake, tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhine River
The Rhine ( ) is one of the major rivers in Europe. The river begins in the Swiss canton of Graubünden in the southeastern Swiss Alps. It forms part of the Swiss-Liechtenstein border, then part of the Swiss-Austrian border. From Lake Constance downstream, it forms part of the Swiss-German border. After that the Rhine defines much of the Franco-German border. It then flows in a mostly northerly direction through the German Rhineland. Finally, the Rhine turns to flow predominantly west to enter the Netherlands, eventually emptying into the North Sea. It drains an area of 185,000 km2. Its name derives from the Gaulish ''Rēnos''. There are two German states named after the river, North Rhine-Westphalia and Rhineland-Palatinate, in addition to several districts (e.g. Rhein-Sieg). The departments of Bas-Rhin and Haut-Rhin in Alsace (France) are also named after the river. Some adjacent towns are named after it, such as Rheinau, Stein am Rhein, Rheineck, Rheinfelden ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mississippi Basin
The Mississippi River is the primary river of the largest drainage basin in the United States. It is the second-longest river in the United States, behind only the Missouri. From its traditional source of Lake Itasca in northern Minnesota, it flows generally south for to the Mississippi River Delta in the Gulf of Mexico. With its many tributaries, the Mississippi's watershed drains all or parts of 32 U.S. states and two Canadian provinces between the Rocky and Appalachian mountains. The river either borders or passes through the states of Minnesota, Wisconsin, Iowa, Illinois, Missouri, Kentucky, Tennessee, Arkansas, Mississippi, and Louisiana. The main stem is entirely within the United States; the total drainage basin is , of which only about one percent is in Canada. The Mississippi ranks as the world's tenth-largest river by discharge flow, and the largest in North America. Native Americans have lived along the Mississippi River and its tributaries for thous ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
