The UKs evolving landscape- River and flooding

• What are the three sections of a river?

  Upper course, middle course, and lower course
• How does the shape of the river change in different sections?


  The river starts as narrow and v-shaped tributaries in the upper course, becomes rounder and deeper in the middle course, and is wide and deep in the lower course.
• What is the characteristic shape of tributaries in the upper course?


  Narrow and v-shaped
• What happens to the tributaries as they flow downstream?


  They combine to fill up the river channel further down.
• What is the gradient like on the sides of the tributaries in the upper course?


  The sides tend to be steep with a large gradient.
• How does the channel shape change in the middle course of the river?


  The channel becomes rounder and deeper to accommodate more water.
• What effect does increased water volume have on the energy of the water in the middle course?


  More water increases the energy of the water, leading to more erosion.
• What is the flat and low-lying area around the river channel called?

  Floodplain
• What characterizes the lower course of the river?


  The river carries the largest volume of water in a very wide and deep channel.
• What are the ridges on either side of the river banks called in the lower course?

  Levees
• How does the speed of water travel vary between the upper and lower courses?


  Water travels faster in the lower course due to less friction from the riverbed.
• What causes friction in a river?


  Friction occurs between the water and the riverbed, slowing the water down.
• How does the channel size affect the velocity of water flow?


  As the river channel gets bigger, less water is in contact with the riverbed, increasing the velocity of the water.
• What type of erosion occurs predominantly in the upper and middle courses of a river?


  Erosion
• What are the two types of erosion that can occur along a river?

  Vertical erosion and lateral erosion
• What is abrasion in the context of river erosion?


  Abrasion is when rocks carried by the water scrape against the sides of the river, wearing away the channel.
• How does attrition affect the size and shape of river load?


  Attrition reduces the size and shape of rocks and pebbles as they hit against each other.
• What is hydraulic action in river erosion?


  Hydraulic action is when water under high pressure forces cracks in rocks to widen and eventually collapse.
• What is corrosion (solution) in the context of river processes?


  Corrosion is the gradual dissolution of chemical compounds in rocks by river water.
• What is the term for the material transported by rivers?

  Load
• What are the four types of transportation processes in rivers?

  Solution, suspension, saltation, and traction

  
• How does solution transport material in a river?


  Solution involves chemicals being dissolved in the river water.
• What is suspension in river transportation?

  Suspension occurs when particles and small rocks are light enough to float within the water.
• How does saltation transport material in a river?

  Saltation involves pebbles and small rocks bouncing along the river channel.
• What is traction in river transportation?


  Traction is when large rocks are rolled along the riverbed.
• Why is it important to know the definitions of erosional and transportational processes in rivers?


  Knowing the definitions helps in answering exam questions accurately and gaining easy marks.
• What is deposition in the context of river processes?


  Deposition is the dropping of the river's load when the water decreases in speed.
• Where does the heaviest material get deposited in a river?


  Heaviest materials are deposited first in the upper course.
• What is the most deposition that occurs in a river?


  The most deposition occurs in the lower course of the river.
• What are the typical landforms found in the upper course of a river?


  Waterfalls, interlocking spurs, and V-shaped valleys
• What characterizes the middle course of a river?


  The middle course has a mixture of erosional and depositional landforms.
• What are the typical landforms found in the lower course of a river?


  Floodplains, ox-bow lakes, and river estuaries
• What is the predominant river process in the upper course?


  Erosion is the predominant river process in the upper course.
• How do interlocking spurs form in the upper course of a river?


  Interlocking spurs form where the river curls around resistant rocks due to low energy.
• What is a waterfall and how does it occur?


  A waterfall occurs when a river flows over rocks with different resistances to erosion.
• How do gorges form from waterfalls?


  Gorges form as waterfalls retreat upstream, leaving behind a steep valley carved into the rock.
• What happens to the soft rock when a river flows over hard and soft rock?


  The soft rock erodes more quickly, creating a step and undercutting the hard rock.
• What is the role of gravity in the formation of waterfalls?


  Gravity causes the unsupported overhang of hard rock to collapse, deepening the plunge pool.
• How do meanders form in a river?


  Meanders form as water travels faster on the outside of a bend, causing lateral erosion and sediment deposition on the inside.
• What happens to the river's energy on the outer edge of a bend?


  The water travels faster, leading to lateral erosion and the formation of a river cliff.