1.1.10 Impacts of human activity on coasts

Positive impacts of human activity:

• Adoption of sustainable management and conservation of coastal environments, using soft engineering techniques

• Increasing use of integrated shoreline management strategies, which consider all the conflicting needs and constraints along the coast rather than taking a piecemeal approach

• Conservation strategies

  • Range from total protection to strategies allowing human activity.

  • Vary in scale

  • Examples include

    • World heritage sites, such as Great Barrier Reef

    • National marine reserves (known as marine conservation zones in England and wales)

    • Sites of special scientific interest (SSSIs), for example Sefton coast, including the Ainsdale sand dunes national nature reserve in Merseyside

Negative impacts of human activity

• Offshore dredging

  • Dredging is the extraction of sand and gravel from the seabed for use in construction, especially of sea defences. It provides the material for beach nourishment schemes.

  • Negative effects include:

    • Destruction of seabed habitats and the marine food web

    • Changes to wave types and sediment flows, resulting in changes in the beach profile, which can increase the rate of erosion of waves travel further up the beach

• Erosion of sand dunes

  • Sand dunes are fragile environments which are vulnerable to damage from human activity. There are 4 types of impact:

    Impact	Description
    Conversion	The dune area is used for urbanisation or activities such as golf courses. Natural vegetation is altered or removed, changing the dune environment
    Removal	Sand is removed for another use, such as industry, or to improve transport or access tot he beach. This allows further erosion but he wind
    Overuse	Dunes are used as an amenity for recreation activities, tourism or as military training areas. Overuse results in vegetation removal, increasing the rate of wind erosion
    External factors	Human activity in another part of the coast affects the dune system. For example, the building of sea defences reduces sediment input to the dunes

• Impacts can be reduced by management:

  • Complete reconstruction in heavily damaged areas

  • Restoration by revegetation and fencing to limit access

  • Removal of external factors

Managing the impacts of human activity on coastal processes and landforms

• Most countries now adopted an integrated coastal zone management strategy (ICZM)

  • ICZM is a form of sustainable management, which tries to balance environmental, social, cultural and recreational needs within the limits controlled by natural factors

  • It involves the participation of all stakeholders in the coastal zone, and aims to meet the needs of all involved

  • Where applicable, it uses defence mechanisms that enhance the environment

  • It aims to meet the needs of the present population while maintaining the potential of the area for future generations

  • Increasingly, the management has to work across boundaries

Case study- Ainsdale sand dunes, south Lancashire

• Cover 7km² of the Sefton coast sand dune system

• They are recognised as an area of special interest for wildlife

• Large numbers of visitors are attracted to the area- 5 million people live within an hours drive of the dunes

• People are attracted by the wide beaches, but also enjoy walking in the dunes and driving quad bikes and 4×4 vehicles

• Footpath erosion and other activities remove the vegetation, which can result in blow-outs and rapid erosion of the dunes by wind

• The Ainsdale sand dunes are a Natural Nature Reserve, managed by Natural England

• The management strategy includes the following:

  • A zoning system is used on the Sefton Coast as a whole, which recognises honeypot areas such as Ainsdale Beach.

  • In honeypot areas intensive management occurs, providing facilities for visitors, such as car parking.

  • Where visitors are allowed, footpaths are covered in boardwalks to prevent erosion.

  • Attempts have been made to prevent vehicles entering the dune system.

  • Access to the nature reserve itself is by permit only, limiting numbers and so protecting the wildlife habitat.

  • Wardens are employed to manage the area.

  • Restoration work, such as planting in damaged areas, is carried out.

• Since 2010 there has been a reduction in the amount of money spent on management. Fewer wardens are employed to patrol the area, and there are fewer repairs to fences and boardwalks. As a result, more vehicles are driving into the dunes, leading to more damage.