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Floodplains
A floodplain or flood plain or bottomlands is an area of land adjacent to a river which stretches from the banks of its channel to the base of the enclosing valley walls, and which experiences flooding during periods of high 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 the regular flooding of floodplains can deposit nutrients and water, floodplains frequently have high soil fertility; some important agricultural regions, such as the Mississippi river basin and the Nile, rely heavily on the flood plains. Agricultural regions as well as urban areas have developed near or on floodplains to take advantage of the rich soil and fresh water. However, the risk of flooding has led to increasing efforts to control flooding. Formation Most floodplains are formed by deposition on the inside of river meanders and by overbank flow. Wherever ... [...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 an area of study of the discipline hydrology and are of significant concern in agriculture, civil engineering and public health. Human changes to the environment often increase the intensity and frequency of flooding, for example land use changes such as deforestation and removal of wetlands, changes in waterway course or flood controls such as with levees, and larger environmental issues such as climate change and sea level rise. In particular climate change's increased rainfall and extreme weather events increases the severity of other causes for flooding, resulting in more intense floods and increased flood risk. Flooding may occur as an overflow of water from water bodies, such as a river, lake, or ocean, in which the water overtops or breaks levees, resulting in some of ... [...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 an area of study of the discipline hydrology and are of significant concern in agriculture, civil engineering and public health. Human changes to the environment often increase the intensity and frequency of flooding, for example land use changes such as deforestation and removal of wetlands, changes in waterway course or flood controls such as with levees, and larger environmental issues such as climate change and sea level rise. In particular climate change's increased rainfall and extreme weather events increases the severity of other causes for flooding, resulting in more intense floods and increased flood risk. Flooding may occur as an overflow of water from water bodies, such as a river, lake, or ocean, in which the water overtops or breaks levees, resulting in some of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
River
A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of water. Small rivers can be referred to using names such as creek, brook, rivulet, and rill. There are no official definitions for the generic term river as applied to geographic features, although in some countries or communities a stream is defined by its size. Many names for small rivers are specific to geographic location; examples are "run" in some parts of the United States, "burn" in Scotland and northeast England, and "beck" in northern England. Sometimes a river is defined as being larger than a creek, but not always: the language is vague. Rivers are part of the water cycle. Water generally collects in a river from precipitation through a drainage basin from surface runoff and other sources such as groundwater recharge, spr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flood
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 an area of study of the discipline hydrology and are of significant concern in agriculture, civil engineering and public health. Human changes to the environment often increase the intensity and frequency of flooding, for example land use changes such as deforestation and removal of wetlands, changes in waterway course or flood controls such as with levees, and larger environmental issues such as climate change and sea level rise. In particular climate change's increased rainfall and extreme weather events increases the severity of other causes for flooding, resulting in more intense floods and increased flood risk. Flooding may occur as an overflow of water from water bodies, such as a river, lake, or ocean, in which the water overtops or breaks levees, resulting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluvial Terrace
Fluvial terraces are elongated 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.Fairbridge, R. W., 1968, ''Encyclopedia of Geomorphology.'' Reinhold Book Company, New York.Blum, M., and T.E. Tonqvist, 2000, ''Fluvial responses to climate and sea-level change, a review and look forward.'' Sedimentology. v. 47 suppl. 1, pp. 2-48. 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. Chang ... [...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) 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., 2007. ''Fundamentals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flood Control
Flood control methods are used to reduce or prevent the detrimental effects of flood waters."Flood Control", MSN Encarta, 2008 (see below: Further reading). Flood relief methods are used to reduce the effects of flood waters or high water levels. Flooding can be caused by a mix of both natural processes, such as extreme weather upstream, and human changes to waterbodies and runoff. Though building hard infrastructure to prevent flooding, such as flood walls, can be effective at managing flooding, increased best practice within landscape engineering is to rely more on soft infrastructure and natural systems, such as marshes and flood plains, for handling the increase in water. For flooding on coasts, coastal management practices have to not only handle changes water flow, but also natural processes like tides. Flood control and relief is a particularly important part of climate change adaptation and climate resilience, both sea level rise and changes in the weather (climat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1851–1855 Yellow River Floods
The 1851-1855 Yellow River floods resulted in a change of the Yellow River's course, thereafter emptying into the Bohai Sea rather than into the Yellow Sea.Fei, J., Lai, ZP., He, HM. et al. Limnology (2012) 13: 117. https://doi.org/10.1007/s10201-011-0361-5 This natural disaster is thought to have been a major cause of the Taiping Rebellion The Taiping Rebellion, also known as the Taiping Civil War or the Taiping Revolution, was a massive rebellion and civil war that was waged in China between the Manchu-led Qing dynasty and the Han, Hakka-led Taiping Heavenly Kingdom. It last ... and Nian Rebellion. References 1851 in China Yellow River Floods in China {{China-history-stub Yellow River floods ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2008 Bihar Flood
The 2008 Bihar flood was one of the most disastrous floods in the history of Bihar, an impoverished and densely populated state in India. The Koshi embankment near the Indo-Nepal border (at Kusaha VDC, Sunsari district, Nepal) broke on 18 August 2008. The river changed course and flooded areas which had not been flooded in many decades. The flood affected over 2.3 million people in the northern part of Bihar. Incident On 18 August 2008, heavy monsoon rains and poor maintenance caused a breach in the Kosi embankment. Water passed through the breach at an estimated 3675 cubic meters per second (129,800 cusecs), flooding many villages in Nepal and hundreds of villages in northern Bihar. The flood submerged most of the Kosi alluvial fan area, which is very fertile, with a dense agrarian population. Background The Kosi River's upper basin in southern Tibet and eastern Nepal drains some 60,000 km2 of mountainous terrain, a region that tectonic forces are elevating by abo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Braid Bar
Braid bars, or mid-channel bars, are river landforms typically present in braided river channels. These formations have many names, including medial, longitudinal, crescentic, and transverse bars, as well as the more colloquial sandflat. Braid bars are distinguished from point bars due to their presence in the middle of a flow channel, rather than along a bank of the river channel. Formation Braid bars often originate from remnants of point bars or the growth of mid-channel unit bars in braided rivers. These features typically form in rivers with a high sediment load, within channels characterized by a large bed load and easily- eroded bank material. There are several mechanisms of formation. One explanation is that flow in the river may be redirected over a point bar, wherein the bar may be separated from the bank and thus become isolated within the channel. This forms a small ‘island’ of sediment, which can evolve into a braid bar. Alternatively, an obstacle s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paraná River Floodplain
Paraná, Paranã or Parana may refer to: Geology * Paraná Basin, a sedimentary basin in South America Places In Argentina *Paraná, Entre Ríos, a city * Paraná Department, a part of Entre Ríos Province * Paraná, Buenos Aires, a settlement in Escobar Partido, Buenos Aires In Brazil *Paraná (state) * Paraná, Rio Grande do Norte, a town * Paraná Province, one of the provinces of the Empire of Brazil * Paranã, a city in the state of Tocantins * Ji-Paraná, a city in the state of Rondônia * Ji-Paraná, a football team from Ji-Paraná, Rondônia state In India * Parana, Agra, a village in Uttar Pradesh, India Rivers *Paraná River, a river that flows through Brazil, Paraguay, and Argentina ** Paraná Delta, at the mouth of Paraná River *Paranã River, a river in the state of Goiás, Brazil *Paraná Urariá, a river in the state of Amazonas, Brazil Other * ARA ''Paraná'', several ships of the Argentine Navy *Paraná Clube, a football team in the Vila Capanema dist ... [...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. 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 the basal shear stress commonly used in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
