Human influences on landscape systems and the management of landscape risk; hard and soft engineering and managed realignment; conflicts between players; and the sustainability of management in a changing climate.

What this dot point is asking

OCR wants you to explain how human activity modifies landscape systems and how the risks (here, mainly coastal recession and flooding) can be managed; to compare hard engineering, soft engineering and managed realignment; to explain the conflicts between the players involved; and to evaluate how sustainable that management is as climate change raises the risk.

The answer

Human influence on landscape systems

Even before defences are built, human activity reshapes landscape systems. Dredging for navigation and aggregates removes sediment; dams trap river sediment that would otherwise feed the coast; land-use change alters runoff and slope stability; and the building of property at the coast raises the value at risk and so the pressure to defend. In glaciated and dryland systems the parallels hold: tourism infrastructure and resource extraction in cold environments, and overgrazing and irrigation in drylands, all alter the sediment and water budgets. Recognising management as an intervention in a system, rather than a list of structures, is what lifts an answer to the higher Levels.

Hard engineering, soft engineering and managed realignment

Hard engineering uses built structures to resist the sea. Sea walls reflect wave energy (but cause scour and are expensive), groynes trap longshore drift to widen beaches (but starve downdrift coasts), and rip-rap and gabions absorb energy. Soft engineering works with natural processes: beach nourishment adds sediment to widen beaches, and dune regeneration and marsh creation rebuild natural buffers. Managed realignment (retreat) deliberately moves the line of defence landward, surrendering low-value land to let the sea create salt marsh that itself absorbs wave energy. The four Shoreline Management Plan policies summarise the choices: hold the line, advance the line, managed realignment and no active intervention.

Players, conflict and decision-making

Management decisions involve many players with conflicting attitudes: residents and businesses usually want their property held; local councils weigh local economies and political pressure; the Environment Agency applies national cost-benefit rules at the cell scale; conservation groups may favour realignment to create habitat; and insurers influence what is viable. Because defending one place can harm another within the same sediment cell, and because public money is finite, decisions are inherently contested. A strong answer treats the chosen "future" for a stretch of coast as a negotiated, political outcome, not a purely technical one, a clear synoptic link to the place and governance topics in Component 2.

Sustainability in a changing climate

Sustainability asks whether management can be maintained without unacceptable economic, social or environmental cost, now and for future generations. Climate change sharpens the question: sea-level rise and stronger storms raise the future cost and failure risk of hard defences, while shrinking the period over which they remain cost-effective. This tilts the long-run balance towards managed realignment and soft engineering, which adapt with the system, though they require honest engagement with the communities who bear the social cost. The most sustainable strategy is increasingly seen as integrated, cell-scale planning that combines selective defence of high-value assets with realignment elsewhere.

Examples in context

Example 1. Medmerry managed realignment, West Sussex (2013). The Environment Agency deliberately breached an old, expensive shingle bank and let the sea flood low-lying farmland, creating around $300$ ha of new intertidal salt marsh. The scheme cost roughly £28 million but protects Selsey and nearby caravan parks better than the failing defence did, while creating wave-absorbing habitat. Medmerry is the standard example of soft engineering / retreat the line delivering both flood protection and environmental gain, and of how a whole-cell, sustainability-led approach can beat holding a hard line everywhere.

Example 2. The Holderness Shoreline Management Plan, East Yorkshire. Most of the rapidly eroding Holderness coast is designated no active intervention, reflecting the high cost of holding the line against the low value of farmland, while settlements such as Hornsea and Withernsea are defended (hold the line). The defences at Mappleton trap longshore drift and starve the cliffs immediately south, illustrating how a hold-the-line decision in one place imposes costs downdrift. The plan pits residents who lose homes against an Environment Agency applying cell-scale cost-benefit rules, showing the conflict and contested decision-making at the heart of the topic.

Try this

Q1. State one advantage and one disadvantage of beach nourishment. [2 marks]

• Cue. Advantage: works with natural processes and looks natural, widening the protective beach; disadvantage: it must be repeated regularly and so has an ongoing cost.

Q2. Explain why climate change strengthens the case for managed realignment. [4 marks]

• Cue. Sea-level rise and stronger storms raise the future cost and failure risk of hard defences and shorten their cost-effective life, while realignment creates natural buffers that adapt with the rising sea.