Coastal management
[2] With three-quarters of the world population expected to reside in the coastal zone by 2025, human activities originating from this small land area will impose heavy pressure on coasts.
[4] Other types of port structure such as rubble mounds and arched breakwaters built by means of timber floating caissons were used also.
The resultant use of artificial beaches and stabilized dunes as an engineering approach was economically viable and more environmentally friendly.
The Group proposed that the Council of Europe, cooperate with the Coastal & Marine Union (EUCC) and United Nations Environment Programme (UNEP).
Alternatively, integrated coastal zone management approaches may be used to prevent development in erosion- or flood-prone areas, reducing the need to address the changes.
Soft options such as beach nourishment protect coastlines and help to restore the natural dynamism, although they require repeated applications.
Examples from erosion include: Koge Bay (Dk), Western Scheldt estuary (Nl), Chatelaillon (Fr) and Ebro delta (Sp).
Coastal erosion is already widespread, and there are many coasts where exceptional high tides or storm surges result in encroachment on the shore, impinging on human activity.
They will experience a so-called "coastal squeeze" whereby ecological or geomorphological zones that would normally retreat landwards encounter solid structures and can migrate no further.
This normally results in protecting the land behind the halosere, as wave energy dissipates throughout the accumulated sediment and additional vegetation in the new habitat.
Groynes are ert or walls perpendicular to the coastline to trap the sedimentation of longshore drift to gradually create a beach and for it ongoing protection by eliminating coastal erosion, often made of greenharts, concrete, rock or wood.
Groynes do not protect the beach against storm-driven waves and if placed too close together create currents that carry material offshore.
Modern seawalls aim to re-direct most of the incident energy in the form of sloping revetments, resulting in low reflected waves and much reduced turbulence.
[citation needed] Revetments are slanted or upright blockades, built parallel to the coast, usually towards the back of the beach to protect the area beyond.
Since the wall absorbs energy instead of reflecting, the surf progressively erodes and destroys the revetment; therefore, maintenance is ongoing, as determined by the structural material and product quality.
Boulders and rocks are wired into mesh cages and placed in front of areas vulnerable to erosion: sometimes at cliffs edges or at right angles to the beach.
When the ocean lands on the gabion, the water drains through leaving sediment, while the structure absorbs a moderate amount of wave energy.
The imported sand should be of a similar quality to the existing beach material so it can meld with the natural local processes and without adverse effects.
Foredune flora are typically plants with a tolerance for salt spray, strong winds and are capable surviving being buried underneath blown sand.
When implementing the stabilization sand dunes on privately owned beaches with multiple owners, coming to a consensual agreement tends to be complicated.
Such water may be discharged or be used to oxygenate stagnant inland lagoons/marinas or used as feed for heat pumps, desalination plants, land-based aquaculture, aquariums or swimming pools.
Twenty four beach drainage systems have been installed since 1981 in Denmark, USA, UK, Japan, Spain, Sweden, France, Italy and Malaysia.
Coastal and estuarine ecosystems act as buffer zones against natural hazards and environmental disturbances, such as floods, cyclones, tidal surges and storms.
[24] The costs of installation and operation vary due to: Coastal managers must compensate for error and uncertainty in the information regarding the erosive processes.
The HWL (H in Figure 1) is the most commonly used shoreline indicator because it is visible in the field, and can be interpreted on both colour and grey scale aerial photographs.
Shoreline data derived from beach profiling is often spatially and temporally limited due to the high cost associated with that labour-intensive activity.
[38] A range of airborne, satellite and land based remote sensing techniques can provide additional, mappable data.
[40] The advancement of coastal video systems in the twenty-first century enabled the extraction of large amounts of geophysical data from images.
The main advantage of video analysis lies in the ability to reliably quantify these parameters with high resolution space and time coverage.
Another assessed the added value of high resolution video observations for short-term predictions of near shore hydrodynamic and morphological processes, at temporal scales of meters to kilometres and days to seasons.
