Unit Pages

Wednesday, September 30, 2015

2.3.4 - The Lithosphere (KQ3): Slope Management Policies

Slope Management Policies

OK...so we have these mass movement issues...how should we best manage them?  There are 4 main techniques that you will discover here:  slope angle reduction, afforestation, drainage, and surface protection. 

Slope Angle Reduction

If it is determined that an area is going to be prone to landslides due to a steep slope, soil can be moved in to reduce the grade (angle) to try and prevent the likelihood of mass movements along them.  If an area has been cut away, bringing in land to fill the void may also take much of the risk of mass movement away.

Afforestation

Afforestation is planting trees and vegetation in areas where currently none grows.  For the purposes of mass movements, this is done to stabilize the land by providing leaf litter and root structure.  Reforestation is the process of reclaiming a land to it original state, one it is found that be deforesting, it is susceptible to mass movements.  Replanting trees can increase drainage into the ground and prevent water from eroding the soil away.  Also, trees provide transpiration, which is how they soak up the water and evaporate it back in the air.

Drainage

Areas in which it is determined landslides may occur may set up drainage systems to divert water away from slopes and into established waterways.  This can be done by making troughs in the land that diver the water away or with pipes that bring the water around the areas in danger.

Surface Protection

Areas may be covered with vegetation or other natural material (like mulch) in order to protect it from flowing water or air.  This may be the easiest measure to protect against mass movement, but bring with it the obvious hurdle that it must be replenished at certain intervals if the material is just sitting on the ground, rather than planted in it.


Just a thought...Ask yourselves, without human interference, would all of these policies be necessary?  Or are we just cleaning up our own mess?

3 comments:

  1. This was so helpful! especially beofre my exams,i didnt know where to check,cuz in AICE we dont have a textbook for EVM...but the methods were explained pretty well,and tbh this fetched me 6 marks in the tests...so thanks alot!

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  2. thank you this is really helpful in guiding my students for the AS Level EM

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    1. No worries! I just worry about the change in syllabus next year and having to do it all over again. I really hope they put out a textbook.

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