River Landscapes

?
View mindmap
  • River Landscapes
    • Changes in rivers and their valleys
      • Drainage basin - area of land drained by a river and small streams
        • Long profile- shows how the gradient of a river changes downstream
          • Cross profile- shape of a valley from one side across to the other
    • River Processes
      • River erosion and landforms
        • Deposition landforms
          • River landforms on River Tees
            • Factors increasing flood risk
              • Hard engineering- floods
                • Soft engineering- floods
                  • Managing floods at Branbury
                    • Branbury: 50km north of Oxford, population 45 thousand, most of the town is on a floodplain.
                      • The scheme was needed because Branbury has been flooded in 1996, causing 12.5 million in damages and 2007.
                        • Raised A361 stays open during floods, Quality of life changes like footpaths, less anxiety about flooding.
                          • Scheme costed 18.5 million pounds, paid partly by the environment agency
                            • 400 houses and 70 businesses has been protected
                              • Earth needed to build for embankment, creating a small resevoir in the process, new havitiat made.
                  • Afforestation- planting trees makes the water to get soaked up, slowing flooding down
                    • Wetlands- places allowed to flood, helps downstream
                      • Floodplain zoning- restricts land to use used on a floodplain, reduces losses.
                        • River restoration- restroing the river to its original course.
                • Dams and resevoirs-  Wildey used, multiple uses and effective but is expensive.
                  • Channel straightning- sometimes lined with concrete, cut through meanders, looks unsightly
                    • Embankment- raised bank, effective but may be expensive.
                      • Flood releif channels- used to bypass areas
              • River floods usually occur after long periods of rain, flash floods mean heavy rainstorms physical and human causes for floods
                • Precipitation- floods usually happen after long periods of rain
                  • Geology- Impermeable rocks make the water flow into the river
                    • Relief- Steep slopes means water flows quickly.
                      • Urbanisation- Tarmac roads
            • River Tees- North West England, flows into the north sea
              • High force, Rivers upper course, waterfall, drops 20m, have an undercut and a gorge
                • Lots of meanders and oxbow lakes.
          • Meanders- Bends in a river in lowland areas, constantly change shape and position
            • Ox bow lake, As meanders migrate across the valley they erode each other.
            • River erosion and landforms
              • Deposition landforms
                • River landforms on River Tees
                  • Factors increasing flood risk
                    • Hard engineering- floods
                      • Soft engineering- floods
                        • Managing floods at Branbury
                          • Branbury: 50km north of Oxford, population 45 thousand, most of the town is on a floodplain.
                            • The scheme was needed because Branbury has been flooded in 1996, causing 12.5 million in damages and 2007.
                              • Raised A361 stays open during floods, Quality of life changes like footpaths, less anxiety about flooding.
                                • Scheme costed 18.5 million pounds, paid partly by the environment agency
                                  • 400 houses and 70 businesses has been protected
                                    • Earth needed to build for embankment, creating a small resevoir in the process, new havitiat made.
                        • Afforestation- planting trees makes the water to get soaked up, slowing flooding down
                          • Wetlands- places allowed to flood, helps downstream
                            • Floodplain zoning- restricts land to use used on a floodplain, reduces losses.
                              • River restoration- restroing the river to its original course.
                      • Dams and resevoirs-  Wildey used, multiple uses and effective but is expensive.
                        • Channel straightning- sometimes lined with concrete, cut through meanders, looks unsightly
                          • Embankment- raised bank, effective but may be expensive.
                            • Flood releif channels- used to bypass areas
                    • River floods usually occur after long periods of rain, flash floods mean heavy rainstorms physical and human causes for floods
                      • Precipitation- floods usually happen after long periods of rain
                        • Geology- Impermeable rocks make the water flow into the river
                          • Relief- Steep slopes means water flows quickly.
                            • Urbanisation- Tarmac roads
                  • River Tees- North West England, flows into the north sea
                    • High force, Rivers upper course, waterfall, drops 20m, have an undercut and a gorge
                      • Lots of meanders and oxbow lakes.
                • Meanders- Bends in a river in lowland areas, constantly change shape and position
                  • Ox bow lake, As meanders migrate across the valley they erode each other.
                • Floodplains- wide flat areas in middle and lower, created by migrating meanders and floods
                  • Levees, low flow deposition raises the river bed, so it floods alot.
                    • Estuary- Where the river meets the sea. simple.
              • 3 landforms which are at upper middle and lower respectivly
                • Interlocking spurs- mountain stream erodes vertically to create a v shaped valley and winds around areas of resistant rock to cut trough the valley
                  • Waterfalls, as a river flows downstream it encounters different rock types, soft rock is easily eroded, causing steps to be made, but eventually retreats
                    • Gorges- narrow, steep sided valley found downstream of a retreating waterfall, but can form in other ways such as glacial hanging valleys
          • Floodplains- wide flat areas in middle and lower, created by migrating meanders and floods
            • Levees, low flow deposition raises the river bed, so it floods alot.
              • Estuary- Where the river meets the sea. simple.
        • 3 landforms which are at upper middle and lower respectivly
          • Interlocking spurs- mountain stream erodes vertically to create a v shaped valley and winds around areas of resistant rock to cut trough the valley
            • Waterfalls, as a river flows downstream it encounters different rock types, soft rock is easily eroded, causing steps to be made, but eventually retreats
              • Gorges- narrow, steep sided valley found downstream of a retreating waterfall, but can form in other ways such as glacial hanging valleys
      • Two types of erosion, vertical and lateral
        • Four processes of river erosion
          • Hydraulic action, Force of water hitting banks and bed
            • Abrasion, load carried by river hits banks, dislodging particles
              • Attrition, stones carried by river knocks into each other.
                • Solution, alkaline rocks are dissolved by slightly acidic water.
                  • Processes of transportation, Solution, suspension, traction, saltation, check back to Coast landscapes
                    • Size and amount of load carried depends on the rivers velocity
                      • When velocity decreases, and no longer has energy for carrying the sediment, it deposits it
                        • Lots of deposition at the mouth due to gentle gradient

Comments

No comments have yet been made

Similar Geography resources:

See all Geography resources »See all Coastal zones resources »