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Kwaaihoek is a coastal region found along the east coast of South Africa near East London - NSC Marine Sciences - Question 5 - 2024 - Paper 1
Question 5
Kwaaihoek is a coastal region found along the east coast of South Africa near East London. This 8 km long stretch of largely unspoiled dunes consists of three headla... show full transcript
Worked Solution & Example Answer:Kwaaihoek is a coastal region found along the east coast of South Africa near East London - NSC Marine Sciences - Question 5 - 2024 - Paper 1
Step 1
Explain how dunes are formed.
Answer
Dunes are formed as a result of sediment being transported to the coast from inland rivers. This sediment is carried by longshore drift, which moves it along the coastline. Onshore winds also play a vital role in forming dunes by moving the sediment inland.
Aeolian movement occurs where wind erodes the sediment, causing it to be deposited in a series of ridges, forming the dune structure. Over time, as sediment accumulates, the dunes can develop into larger structures, supporting various vegetation types which help stabilize the sand, forming a mature dune ecosystem.
Step 2
Discuss the role vegetation plays in the formation of a stable dune ecosystem.
Answer
Vegetation plays a critical role in stabilizing dunes through its root systems, which bind the sand together, preventing erosion and loss of sediment. Specifically, pioneer plants establish themselves first on bare sand, contributing organic matter that enhances soil fertility over time. As these plants die and decay, they create a more nutrient-rich environment that supports other plant species.
Over the long term, a diverse set of plant life forms a robust ecosystem that can trap sand, reducing the movement of sediment and enhancing the overall stability of the dunes.
Step 3
Describe the TWO different engineering approaches that can be used AND compare their effectiveness for this site.
Answer
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Hard Engineering: This approach includes structures such as sea walls, groynes, and breakwaters. These structures can effectively reduce the impact of wave action and prevent coastal erosion. However, they often come with high costs and may lead to increased erosion in adjacent areas, detrimental to the ecosystem.
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Soft Engineering: This method focuses on using natural processes to mitigate erosion, such as planting vegetation or using biodegradable materials. It tends to be more environmentally friendly and maintains the natural aesthetics of the area while also being less costly and easier to maintain. However, soft engineering solutions can be less immediate in their effectiveness compared to hard engineering methods, which provide a quicker fix but may have negative long-term consequences.
Step 4
Motivate whether it is important to conduct an environmental impact assessment (EIA) before deciding on the type of engineering approach to use.
Answer
Conducting an Environmental Impact Assessment (EIA) is essential as it allows specialists to gauge how the proposed engineering structures will affect the dune ecosystem. This assessment helps identify potential adverse effects such as habitat destruction, changes in sediment transport, and impacts on the local biodiversity. By thoroughly evaluating these factors, the municipality can make informed choices that ensure the sustainability of both the tourism industry and the natural environment. Furthermore, it can help mitigate risks like decreased tourism revenue, ensuring the area's economic viability.
Step 5
Justify whether constructing an engineering structure would benefit the local municipality.
Answer
Constructing an engineering structure can provide immediate benefits by ensuring accessibility to popular tourist locations, which is vital for the local economy. However, it can also introduce long-term challenges like potential environmental degradation. Hence, while the short-term solution may attract more tourists, it is crucial to weigh this against sustainable practices that align with the community's values and environmental goals. The chosen approach should not only enhance access but also preserve the integrity of the coastal ecosystem.