Rivers 0.0 / 5 ? GeographyWater and riversGCSEAQA Created by: Chloe-ManningCreated on: 03-05-16 19:37 Attrition Rocks fall into each other causing them to weaken and bits to break off. 1 of 27 Solution/Corrosion The river flows over soluble rocks. The rock dissolves in the river. 2 of 27 Abraision/Corassion The river load hits the bed and banks causing more matirial to break off. 3 of 27 Hydraulic Action The fore of the water hitting the bed and bank. More affective in deep, fast flowing water. 4 of 27 Traction Large rocks draged it along the bed. 5 of 27 Saltation Small stones moved by bouncing. 6 of 27 Suspension Carries very fine material in the water. 7 of 27 Solution Load dessolved in water 8 of 27 Vertical erosion 1st part of a valley. The river cuts down and deepens the valley. 9 of 27 V shape valley 2nd part of a valley. The river widens the valley as it deepens. 10 of 27 3rd part of a valley The river widens the calley more. A flat bottom is made by erosion and deposition of meanders. 11 of 27 Drainage Basin An area drained by the river 12 of 27 Tributary A stream or small river that flows into a bigger one. 13 of 27 Confluance Where a small river joins a large one. 14 of 27 Water shed The boundary between 2 river basins. The top of the valley. 15 of 27 Velocity - lowland river Fast flowing in center, no friction against rocks or wind 16 of 27 Velocity - upperland stream Slower flowing as more friction. White water is loss of energy 17 of 27 Upstream Narrow. Shallow. Slow. Small discharge. Small amount of load. Bigger rougher load. Rougher bed. Steeper 18 of 27 Downstream Deep. Wide. Fast. High discharge. Lots of load. Small smooth load. Smooth bed. Flat. 19 of 27 Wetted perimiter length of bed and both banks added together 20 of 27 Hydrolic radius cross section area / wetted perimeter 21 of 27 Levees Raised banks along lower corse of river. Natural or artificual. 22 of 27 Causes of flooding Snow melt. Deforestation. Construction. Sudden, vast amounts of precipitation. 23 of 27 Advantages of dams Reliable water source. Improves local econamy. Reduce impact of flooding. Hydro-electric power. 24 of 27 Disadvantage of Dams Unsightly. Expensive to build. destroys local wildlife. Some people have tol lose their homes 25 of 27 Hard engineering Man-made or modifying natural oneswoth technology. Dams, Levees, Deepening/widening channel, removing meanders. MEDC 26 of 27 Soft engineering Working with natural processes and avoiding flood plains. Flood plain zoning, text flood warning, only grazing in flood plains 27 of 27
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