Human Impacts on Coastal Processes

2 types of human impact

• Land-based impacts

• Sea-based impacts

Land-based impacts include….

• Dredging of estuaries.• Clearance of Mangroves• Construction of port or commercial facilities.• Canal Estates.• Beachfront property development.• Marinas.• Sand mining and extraction.• Construction of coastal defences.

Sea-based impacts include….

• Waste disposal.• Recreational fishing.• Water sports.• Oil and gas production.• Commercial shipping.• Oil spills.

The effects of these activities include…..

• Change to the physical character of the coast.

• Change to our natural heritage.

• Change in the use of our coastal areas.

Change to the Physical Character

• Loss or decline of landscape value.• Loss of amenities i.e. beaches and dunes.• Disruption of sediment movement.• Impact on the character and nature of

coastal towns.

Changes to the Natural Heritage

• Loss or decline of habitat.• Disruption to coastal ecosystems.• Loss of biodiversity.• Decline in fish and shellfish resources.• Loss of natural landscapes.

Change in coastal use

• Conflict over the use of coastal zones.• Incompatible land uses, should be located

elsewhere.• Pressure for services to meet the demands

of coastal developments.• Demand for residential land.• Impact on existing business and

employment.

The Sediment Budget

• This is a balance between.• The sediment being added to the coastal

zone.• The sediment being lost from the coastal

zone.• Compartments• Budget = inputs – outputs.

How humans interfere with the sediment budget

• Remove sediment.

• Block the flow of sediment.

• Damage coastal sediment landforms.

Coastal Defences

• Put in place to either build up beaches or to stop wave encroachment.

• 2 types of defence management options.

Hard Management Options

• Groynes.• Breakwaters.• Sea Walls.• Rip Rap.

Soft Management Options

• Beach Nourishment.• Buy-Back Schemes.• Protection & revegetation of Sand Dunes.