Disaster Management - Landslides

Landslides :

The movement of earthy materials like coherent rock, mud, soil, and debris from higher region to lower region due to gravitational pull is called landslides.

Causes Of landslides :

1. Down hill movement of earth is mainly caused by rain, forces, either increasing the top material weight, lubricating the various layers, or making the slope too steep.

2. Movement of heavy vehicles on the unstable sloppy regions create landslides.

3. Earthquake, shocks, vibrations and cyclone create landslides.

4. Erosion in the hilly tract due to run-off water during rainy period also leads to land slides.

5. Underground caves and underground mining activities may also lead to subsidence.

6. Unconsolidated sediments exposed due to logging, road or house building also cause landslides.

Effects of Landslides :

1. Landslides block the roads and diverts the passage.

2. Erosion of soil increases.

3. Sudden landslides damage the houses, crop yield, live stock etc.,

Landslides Management :

It is very difficult to control landslides. How ever, these can be minimized by

1. Unloading the upper parts of the slope.

2. Improving the cultivation in the sloppy region, the roots of which provide cohesion and retards the flow of water and its erosion capacity.

3. Steepness of the slope can be reduced by developing benches.

4. Concrete support can be made at the base of the slope.

5. Draining the surface and sub surface water from the weak sloppy regions.

6. Soil stabilization using some chemical (quick lime) is also effective in weak areas.

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