How can erosions be prevented?

Answer 1

Erosion is the process where material is moved from one location on the surface of the earth to another. There are a number of techniques used to try and control this process.

The introduction of plants is used quite often for bringing soil erosion under control. The roots that they form in the soil act to bind or hold the soil together preventing it from being washed or blown away. Also vegetation cover acts to decrease the rate which rainfall reaches the ground surface helping to reduce run off and in turn reduce the rate of soil erosion by this moving water.

Another method to prevent soil erosion is the use of geosynthetic mats. These are man made sheets or mats composed of various materials that are pegged into place on the surface in localised areas that are prone to erosion (for example footpaths in national parks that receive significant numbers of hikers).

The lateral movement of sand along a beach (and ultimately along an entire coast line) due to prevailing currents / wind directions can cause significant losses of material. This process is natural and is known as longshore drift. In some areas, to prevent or reduce the impact of longshore drift, groynes (vertical walls of rock fill or even timber) are constructed perpendicular to the long axis of the beach which help prevent longshore drift from removing the sand.

Another coastal protection measure that helps to reduce eriosion and weathering is the use of rock fill (large boulder sized pieces of rock greater than 25.6 cm in diameter) that are placed at the base of cliffs composed of soft materials. These act as breakwaters and dissipate wave energy before it reaches the cliff so preventing or significantly reducing the potential for weathering and erosion.

The above is a summary of a small number of examples of how erosion may be reduced or eliminated. There are probably a significant number of other methods!

For more information on mass movements / landslides which are also a form of erosion and how then can be stopped, please see the related question.

Answer 2

One way to limit the erosion of sediment from beaches is through structure called groins.Groins trap sediment that might be moved along the coast by longshore transport.