The bed and banks can be eroded making it wider, deeper and longer. River processes erosion removes material from a river bed making it deeperwider these pebbles, sand, silt, etc. It is the main method of both vertical and horizontal erosion. Be able to give reasons why and where in a rivers course deposition takes place. Their work was on factors affecting development like you in y10, but you get the idea.
Diagrams and definitions of the key processes of erosion. The start of a river is called the source and the end is called the mouth. Learn river processes with free interactive flashcards. River processes gcserevision, geography, riverlandscapes. Choose from 500 different sets of river processes flashcards on quizlet. Channels in alluvial plains glossary bibliography biographical sketch to cite this chapter summary channel. River processes a resource identifying the different river processes of erosion, transportation and deposition. It emphasises water flows basic principles and characterisation, fluvial sediment, processes of erosion and sediment transport, bedforms that result from flowbed sediment interactions in sand and gravel, flow and sedimentary processes in curved, braided and. River based flooding is among one of the most frequent and widespread natural hazards. Book chapter rivers are dynamic systems and they have shaped the uk in many ways over thousands of years. Firstly, the movement of water across the stream bed exerts a shear stress directly onto the bed. Linkages between flow regime, biota, and ecosystem processes. Using the ocr b textbook, page 8, complete the table below. This happens in the middle and lower stages of a river.
How do physical processes and relief change the shape and functioning of the river garonne as it travels from source to mouth. At first the basic elements of river hydrology like the catchment and all the components of the mass balance equation are described. River processes erosion, transportation and deposition. Erosion predominates in the upper reach area of a drainage basin, and valleys composed of channels and slopes are formed. As a river flows along its course it undertakes 3 main processes which together help to shape the river channel and the surrounding valley. Rivers begin in upland areas and flow downhill towards the sea. Fluvial processes and landforms fluid agents running water is one of the four fluid agents that carry out denudation the others are glacial ice, waves and currents, and wind running water fluvial action is by far the dominant agent shaping the land surface some basic concepts before we go on to fluvial processes and. They carve channels, form valleys,transport and deposit regolith over great distances and other material to form other types of landforms. Solutionchemical action by water, dissolves minerals. Fluvial processes include the motion of sediment and erosion or deposition on the river bed. River processes shape the land in different ways as the river moves from its source to its mouth. Hydraulic action would only be effective with a lot of force in the river from a flood. The catchment receives water from precipitation and loses some water in the process of evapotranspiration and the.
Once these sediments are separated from the rocks, erosion is the process that moves the sediments away from its original position. With weathering, rock is disintegrated into smaller pieces. These elements are controlled by factors operating at different spatial and time scales, within and outside of the basin. Corrasion when a river picks up material and then rubs it against its bed and banks. Igcse geography river processes task the four types of erosion. The processes of river erosion page 19 of bp gives a good account of river erosional processes, read that and then read the text below to reinforce your understanding or confuse you.
Channel processes, river morphology, drainage basin, river system, stream order, hortons laws, alluvial plain, channel pattern, sediment load, rejuvenation. Abrasionthe rivers bedload scrapes the banks and bed of the river. The water can erode the river s channel and the river s load. Pdf this assignment was presented by the author as a routine work of the course curriculum. These processes are erosion, transport and deposition. There are many processes operating in different parts of rivers. Attrition boulders collide with one another as they move down the river, and can break into smaller pieces. Understand that the effectiveness of the river processes will vary according to the volume and. A valid estimate can be made only if the volume of sediment derived by erosive processes can be accurately determined, the boundaries of the source area are definable, and. River processes page 67 erosion can affect the length, depth and width of a river vertical erosion deepens river channels. Along the main river, there are many other smaller rivers which join it called tributaries. A river is a body of water flowing along a natural channel. Get the lesson worksheet get the lesson powerpoint.
River processes introduction there are 3 major river processes happening which shape the land surrounding the river as it makes its way from the source to the mouth. River energy may be used to erode the bed and banks, and transport eroded material. River load in upper course load is dumped in summer due to the low discharge unable to carry the capacity and competence of load at higher flow levels 18. Weathering is the process that changes solid rock into sediments. Tes global ltd is registered in england company no 02017289 with its registered office at 26 red lion square london wc1r 4hq. It emphasises water flows basic principles and characterisation, fluvial sediment, processes of erosion and sediment transport, bedforms that result from flowbed sediment interactions in sand and gravel, flow and sedimentary processes in curved, braided and confluent channels, as well as. A river s load is bits of eroded material, generally rocks, that the river transports until it deposits its load. A thorough insight into erosional and transport processes and river landforms including. A synthesis of approaches, criteria of use and sensitivity to environmental stressors article pdf available in science of. Erosion also breaks up the rocks that are carried by the river.
River processes and pressures forest gate community. A rivers gradient slope is steepest near the headwaters and gentlest near the mouth. This website and its content is subject to our terms and conditions. As rivers flow from their headwaters to their base level they carve valleys. A resource identifying the different river processes of erosion, transportation and deposition. How river erosion and transportation processes work, from. Fluvial transportation is the m ovement of earth s material enacted by the running water.
There are three main types of processes that occur in a river. Erosion, deposition and materials rivers carry all contribute to how rivers shape surrounding land. However, humans are increasingly degrading fluvial ecosystems by altering their streamflows. There are many natural and dynamic processes happening along a river. It emphasises water flows basic principles and characterisation, fluvial sediment, processes of erosion and sediment transport, bedforms that result from flowbed sediment interactions in sand and gravel, flow and sedimentary processes in curved, braided and confluent channels, as well. Igcse geography river processes and landforms introduction this essay is about how river processes shape landforms at different stages as the river moves from its source to its mouth. Fresh surface water river morphology and channel processes iware matsuda. Erosion occurs by the process of abrasion, and is most effective during times of flood. A river transports, erodes, or deposits sediment load.
The drop gets steeper as the river erodes the soft rock beneath by processes such as abrasion and hydraulic action. Understand and explain river transport processes including traction, saltation, suspension and solution. A river can be divided into the upper, middle and lower course. Students complete a range of activities to help them understand how these processes work along a rivers course. Major concepts linking the structure and functioning of river ecosystem with fluvial processes are presented, followed by a discussion of the impacts of geomorphic. Rivers are perhaps the most important denudation agent. The four forces of erosion are water, wind, glaciers, and gravity. These join with the main river at a point called the confluence. Near the source the river will erode more laterally sideways or vertically downwards 2. Use these case studies, along with the detailed graphics provided, to explain the fluvial processes of erosion, transportation and deposition and explore how they change throughout a rivers course. This occurs mostly in the middle and lower stages of a river.
If the cohesive strength of the substrate is lower than the shear exerted, or the bed is composed of loose. The processes are happening constantly, cutting, shaping and smoothing the land. River processes deals primarily with flow and sediment dynamics in alluvial channels. Diagrams and definitions of the key processes of transportation. What type of erosion becomes more important as the river moves towards the mouth. These processes are known as fluvial processes which relate to erosion, transport and deposition by a river.
Will the river always erode the river bed at the same rate, or could certain weather events change this 3. River capture this is a process where one river captures the headwaters on a nearby stream. Types of erosion river processes aqa gcse geography. Watch these great rsa videos produced by y10 students at the priory school in portsmouth this week. There are four main processes of erosion that occur in rivers. Surface water erodes through river and stream processes. Tectonic earth movements, where the slope of the land changes, and the stream is tipped out of its former course. Jan 21, 20 use these case studies, along with the detailed graphics provided, to explain the fluvial processes of erosion, transportation and deposition and explore how they change throughout a river s course. Teacher powerpoint with diagrams and answer key provided directly onto the slides or in notes section of each slide. The hjulstrom curve a hjulstrom curve is a special type of graph that shows how a rivers velocity affects it competence and its ability to erode particles of different sizes. There are many natural and dynamic processes happening along a.
River erosion river erosion is the wearing away of the land as the water flows past the bed and banks. Erosion is the process that wears away the river bed and banks. Key features and processes of a river basin for revision. All three depend on the amount of energy there is in a river. Jun 18, 2018 diagrams and definitions of the key processes of erosion. Implications for river restoration margaret palmer1 and albert ruhi2 river ecosystems are highly biodiverse, influence global biogeochemical cycles, and provide valued services. As the river passes over the hard rock, the soft rock below is eroded more quickly than the hard rock leaving the hard rock overhanging. A river s channel is eroded laterally and vertically making the channel wider and deeper. Fluvial is a term used in geography and earth science to refer to the processes associated with rivers and streams and the. Erosion involves the transport of rock and soil material subsequent to and during weathering processes. River based flooding is among one of the most frequent and. Includes the four processes of erosion and transportation and deposition. River basin processes free download as powerpoint presentation. Linkages between flow regime, biota, and ecosystem.
A short overview of some problems related to the transport processes in river systems is presented. Sediment in channels researchers have proposed that entrainment and transportation of bedload may be analyzed in terms of stream power. Near their source, rivers are small and do not have a lot of power. The main channel processes or fluvial processes are erosion, transportation and sedimentation. River basin processes drainage basin river free 30day. A synthesis of approaches, criteria of use and sensitivity to environmental stressors article pdf available in science of the total environment 596597. Aug 02, 2014 when a river meets the sea a river will deposit its load because the gradient is generally reduced at sea level and the sea will absorb a lot of energy. Influence of catchment processes on fluvial morphology and. Log in or sign up to manage your videos and for new video alerts log in sign up. River processes drainage basin evolution denudation rates of denudation difficult to do, because quantifying human impact is vague.
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