Question 1: Describe the process of river erosion and explain two different types of erosion that occur in a river.

Answer: River erosion involves the wearing away of the river bed and banks due to the movement of water. Two types of erosion are hydraulic action, where the force of water dislodges particles from the bed and banks, and abrasion, where sediment and rocks carried by the river scrape and grind against the riverbed and banks.

Question 2: Explain how a river's valley is typically shaped during the upper course of a river’s journey.

Answer: In the upper course, the river erodes vertically, creating a steep-sided valley with a narrow, V-shaped cross-section. The process of vertical erosion deepens the valley and forms features like waterfalls and rapids.

Question 3: Identify and describe three features commonly found in the middle course of a river.

Answer: Features in the middle course include: 1) Meanders, which are winding bends in the river caused by erosion and deposition; 2) Slip-off slopes or point bars, formed by deposition on the inside of meander bends; 3) Floodplains, which are flat areas alongside the river that flood during high flow periods and are formed by repeated deposition of sediment.

Question 4: Draw a simple cross-section of a river showing the riverbank, riverbed, and the flow of water during a flood event.

Answer: A correct sketch would show a cross-section with the river flowing in the middle, high water levels on both sides during a flood, the riverbank sloping outward, and the flow of water moving over the banks. The diagram should include labels: riverbed, banks, floodwaters.

Question 5: Explain the process of deposition in rivers and identify two landforms that can be created by deposition.

Answer: Deposition occurs when a river loses energy and drops the sediment it was carrying. Two landforms created by deposition are deltas, where the river meets a standing body of water and deposits sediment, and alluvial fans, which are cone-shaped deposits that form when a river flows from a steep area to a flatter plain.

Question 6: Describe how the velocity of a river changes from its upper course to its lower course and explain the effect on erosion and deposition.

Answer: In the upper course, the river has high velocity due to steep gradient, leading to more vertical erosion. As the river moves downstream into the lower course, the gradient flattens, reducing velocity, which causes more deposition and the formation of features like floodplains and levees.

Question 7: Identify and explain two human activities that can impact a river’s natural processes.

Answer: Building dams can control flow but also cause sediment buildup upstream and reduce downstream erosion. Urban development increases surface runoff, leading to higher flood risks and increased pollution in the river.

Question 8: Sketch a diagram showing a river’s source, its mouth, and the general flow direction. Label these parts clearly.

Answer: A correct sketch would depict a river starting at a highland or mountain (source), flowing downstream across the landscape, and ending in an estuary or sea (mouth). The flow direction should be indicated with an arrow, and labels should identify the source, course, and mouth.

Question 9: Discuss the importance of rivers to human settlements and economies.

Answer: Rivers provide water for drinking, agriculture, and industry, support transportation and trade, and offer recreational opportunities. They also help generate hydroelectric power and are vital for supporting local economies and ecosystems.

Question 10: Explain how a floodplain is formed and why it is important for river management.

Answer: A floodplain is formed over time by the deposition of sediment during frequent floods when the river overflows its banks. It is important for flood management because it acts as a natural buffer zone that absorbs excess water, reducing the risk of flooding in urban areas.