Saturday 10 May 2008

What natural processes shape and put the coastal environment at risk.


Probably the fore most factors when looking into the coastal environment, is erosion. This can consist of visible erosion, which is cliff erosion from the top down, crumbling rock and land slides are common, visible erosion is usually due to underlying erosion that we can not see, the best explanation of this can be found at the BBB bitesize web site linked below. There are four main types o erosion;
Hydraulic action – where the motion of a body of water wears away the river bank from underneath
Attrition - rocks being carried by the tide, currents or other oceanic movements, smashing together and breaking into smaller particles
Abrasion - rocks carried along by the body of water wearing down over time against the sea bed, banks, cliffs and other rocks.
Solution - smaller particles are dissolved into the water, by a movement of friction.
Erosion can be caused by a number of things, of which; wave action, movement of rocks and sand, weathering and of cause sea level rise (SLR).
There have been many negative affects and as the public and conservation trusts are accepting that, although in some areas it is required that the nation’s best efforts are used to project an area, it is some times required that a controlled retreat is required. For a comprehensive action plan for the future concerning sea level rise the nation trust link listed below is by far the best I have com across.
The idea behind coastal defence is to reduce the risks of people and the environment from flooding and coastal erosion by encouraging the provision of technology, producing economical and sustainable defensive measures. The issue s of coastal defence are controlled and the responsibility of DEFRA (the Department for Environment, Food and Rural Affairs) – their website also listed below can provide an in-depth review and conclusion into Coastal defence.
Within the topic of Coastal defence fall’s Coastal protection. Coastal protection authorities (CPA’s), can carry out, if they chose to do so and if it is within national interest, work to protect and preserve the coastline from erosion. This work can include anything from, construction, alteration, improvement, and repair to demolition and removal. Private owners also my chose to protect the coastline purely to protect their assets, this could be anything from landowners to network rail.

The main legislation coastal defence and protection are as flows
Coastal protection; Coastal protection Act 1949
Flood Defences; Water Resources act 1991
Land Drainage Act 1991
Water Act 2003
Environment agency duties; Environment 1995

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