How physical and human processes interact in coastal and river landscapes; the costs and benefits of hard and soft engineering to manage coastal erosion and river flooding; and the conflicts between stakeholders over land use and protection.

What this dot point is asking

This is OCR GCSE Geography B (J384) Component 1, Our Natural World, the management strand of Distinctive Landscapes: "How do people use and manage distinctive landscapes?" OCR expects you to explain how physical and human processes interact in coastal and river landscapes, evaluate the costs and benefits of hard and soft engineering for managing coastal erosion and river flooding, and discuss the conflicts between stakeholders over how land should be used and protected.

How people and physical processes interact

Coasts and river valleys are attractive places: they offer flat land, water, fertile soils, trade and ports, fishing and recreation, so people settle, farm and build there. But this puts homes, farmland and infrastructure in the path of natural processes: coastal erosion wears the land away, and river flooding spreads across the floodplain. Human action can make this worse: building on a floodplain reduces the land that can soak up water, and removing coastal vegetation speeds erosion. Management is the attempt to protect people and property while working with, or against, these processes.

Coastal management

The choice is between hard engineering, soft engineering and managed retreat.

• Hard engineering: sea walls (reflect wave energy, very effective but expensive at thousands of pounds per metre), groynes (trap sediment to build a wider beach, but starve down-drift coasts), rock armour (rip-rap) and gabions (absorb wave energy). Effective but costly and can shift erosion along the coast.
• Soft engineering: beach nourishment (adding sand to widen the beach) and dune regeneration work with natural processes, are cheaper and more natural, but need regular, repeated maintenance.
• Managed retreat (managed realignment): deliberately allowing low-value land to flood, creating salt marshes that absorb wave energy and provide habitat. Cheap and sustainable, but means losing farmland and sometimes homes.

River (flood) management

The same hard-soft split applies to rivers.

Conflicts over land use

Different stakeholders want different outcomes, and this creates conflict.

• Residents and businesses in a threatened town want strong, immediate protection (sea walls, flood defences).
• Farmers on low-value coastal land may lose out if managed retreat is chosen, but the wider scheme may save money.
• Councils must weigh the cost of defences against the value of what is protected (a cost-benefit analysis), so they cannot defend everywhere.
• Conservationists favour soft and natural approaches that protect habitats.

Management therefore involves difficult choices about who is protected, who is not, and at what cost, which is exactly what OCR's evaluation questions test.

Try this

Q1. Explain one benefit and one cost of using soft engineering on a coast. [4 marks]

• Cue. Benefit: beach nourishment works naturally and looks attractive. Cost: it needs repeated, expensive maintenance.

Q2. Suggest why a council might choose managed retreat for a stretch of farmland. [4 marks]

• Cue. Defending low-value farmland is not cost-effective; allowing it to flood creates salt marsh that absorbs wave energy and protects land behind it cheaply.