Coastal Processes and Landforms » Human Impact on Coasts

Introduction to Human Impact on Coasts

Coastal areas are some of the most populated places on Earth, with over 60% of the world's population living within 100km of the coast. This creates enormous pressure on these fragile environments. Human activities can dramatically change coastal processes, sometimes helping to protect the coast but often causing serious damage to natural systems.

Key Definitions:

• Coastal Management: Human strategies to protect coastlines from erosion and flooding.
• Hard Engineering: Artificial structures built to defend against coastal processes.
• Soft Engineering: Working with natural processes to manage coastal areas.
• Sustainable Development: Meeting current needs without harming future generations.

Coastal Management Strategies

Governments and local authorities use various methods to protect coastlines from erosion and flooding. These strategies can be divided into hard and soft engineering approaches, each with different impacts on natural coastal processes.

Hard Engineering Defences

These are artificial structures built to resist the power of waves and prevent erosion. Whilst they can be effective in the short term, they often cause problems elsewhere along the coast.

🏪 Sea Walls

Concrete barriers that reflect wave energy back to sea. They're expensive to build and maintain and can cause increased erosion at their base through wave reflection.

🪨 Groynes

Wooden or stone barriers built perpendicular to the beach. They trap sediment on one side but starve beaches further along the coast of sand and pebbles.

🌋 Rock Armour

Large boulders placed at the base of cliffs to absorb wave energy. They're cheaper than sea walls but can look unsightly and may shift during storms.

Soft Engineering Approaches

These methods work with natural processes rather than against them. They're often more sustainable and environmentally friendly, though they may require more land and ongoing management.

🌴 Beach Nourishment

Adding sand or pebbles to beaches to build them up. This provides natural protection but needs regular topping up as waves naturally move the sediment.

🌿 Dune Regeneration

Planting vegetation to stabilise sand dunes. Marram grass is commonly used as its roots bind sand together and it can survive salty conditions.

🌲 Managed Retreat

Allowing the sea to flood low-lying areas naturally. This creates salt marshes that absorb wave energy but requires relocating people and activities.

Economic Activities and Coastal Impact

Various economic activities along coasts create significant environmental impacts. Understanding these helps us make better decisions about coastal development and management.

Tourism and Recreation

Coastal tourism brings economic benefits but can severely damage fragile environments. Popular beaches face erosion from trampling, whilst development for tourists often destroys natural habitats.

🏖 Positive Impacts

Tourism provides jobs and income for coastal communities. It can fund conservation projects and raise awareness about marine environments. Well-managed tourism can support sustainable development.

⚠ Negative Impacts

Overcrowding damages beaches and dunes. Hotels and restaurants create waste and sewage problems. Water sports can disturb marine life and damage coral reefs.

Fishing and Aquaculture

Commercial fishing and fish farming significantly impact coastal environments. Overfishing depletes fish stocks, whilst fish farms can pollute coastal waters and spread diseases to wild populations.

Climate Change and Sea Level Rise

Human activities are causing global climate change, which particularly affects coastal areas through rising sea levels, changing storm patterns and ocean acidification.

Rising Sea Levels

Global sea levels are rising due to thermal expansion of seawater and melting ice caps. This threatens low-lying coastal areas with increased flooding and erosion. Small island nations face complete submersion within decades.

🌊 Immediate Effects

Increased coastal flooding during storms, saltwater intrusion into freshwater supplies and loss of coastal habitats like salt marshes and mangroves.

🚀 Long-term Consequences

Permanent loss of coastal land, forced migration of coastal populations and collapse of coastal ecosystems. Some Pacific islands may become uninhabitable.

Ocean Acidification

Increased carbon dioxide in the atmosphere is making oceans more acidic. This affects marine life, particularly shellfish and coral reefs, which struggle to build their calcium carbonate structures in acidic conditions.

Sustainable Coastal Management

Effective coastal management requires balancing human needs with environmental protection. This involves integrated approaches that consider all stakeholders and long-term sustainability.

Integrated Coastal Zone Management

This approach considers the entire coastal system rather than managing individual problems in isolation. It involves cooperation between different organisations and considers economic, social and environmental factors together.

🌐 Environmental

Protecting habitats, maintaining biodiversity and preserving natural coastal processes for future generations.

👥 Social

Ensuring coastal communities can continue living and working whilst adapting to environmental changes.

💰 Economic

Maintaining economic activities like tourism and fishing whilst ensuring they don't damage the environment they depend on.

Community Involvement

Successful coastal management requires local community support and involvement. People who live and work in coastal areas often have valuable knowledge about local conditions and are more likely to support management strategies they've helped develop.

Future Challenges and Solutions

As coastal populations continue to grow and climate change accelerates, new approaches to coastal management are needed. These must be flexible, sustainable and able to adapt to changing conditions.

Innovative Technologies

New technologies offer promising solutions for coastal protection. These include floating barriers, artificial reefs and early warning systems for coastal flooding. However, they must be tested carefully to ensure they don't create new environmental problems.

Nature-Based Solutions

Working with natural processes often provides more sustainable protection than hard engineering. Restoring mangroves, coral reefs and salt marshes can provide effective coastal defence whilst supporting biodiversity and local livelihoods.