Using Figure 4 and your own knowledge, assess the relative importance of factors leading to the development of this landscape - AQA - A-Level Geography - Question 2 - 2021 - Paper 1

In assessing the relative importance of factors leading to the development of the landscape shown in Figure 4, it is essential to focus on several key elements:

1. Sediment Availability

The landscape's formation is significantly influenced by the availability of sediment, which is primarily sourced from the Orange River. This sediment supply is crucial for the development of features such as barchan dunes. Without a consistent and substantial supply of sediment, the dunes could not form or would not develop to their current size and complexity.

2. Wind Action

Wind is arguably the most significant agent in shaping the landscape. The prevailing wind direction plays a crucial role in the formation and movement of barchan dunes. The consistent winds from specific directions over time help in the erosion of the sediment and its accumulation in dune shapes. The role of wind includes:

• Deflation: Removing fine particles from the surface, aiding in the formation of low areas where dunes can accumulate.
• Transportation: Carrying sediments across distances, allowing for the redistribution necessary for dune formation.

3. Erosion and Weathering

These processes also contribute to the dynamics of the landscape. The harsh conditions in the Namib Desert, such as extreme temperatures and minimal moisture, facilitate both weathering and erosion. This leads to the reshaping of existing landforms and the maintenance of the sediment supply essential for the barchans.

Conclusion

While all factors are interconnected, wind action and the availability of sediment are paramount. Wind drives the barchan formation process, while sediment availability ensures that there is material for the dunes to form. Thus, it can be concluded that wind and sediment together create the distinctive landforms seen in this part of the Namib Desert.