m74.    How is soil important in the environment?

Topsoil is eroding faster than it forms in about 1 of 3 cases.  The amount of land affected:

               a.  Nepal - 95%

               b.  Peru - 95%

               c.  Turkey - 95%

               d.  Lesotho - 88%

               e.  Madagascar - 71%

               f.  Ethiopia - 53%

               g.  US - 25%

Overgrazing accounts for 35% of the damage. Deforestation causes 30%. Unsustainable methods of farming cause 28%. Desertification occurs when arid or semi-arid land loses its potential for productivity. Moderate desertification is a 10-25% drop in productivity. Severe desertification is a 25-50% drop in productivity. Very Severe desertification is a drop of 50% or more. The indirect cost to the US by erosion is $2.9 million per hour.

e01.    What is biodiversity?

e04.    What sorts of resources do rangelands produce?

e06.    What is “wilderness” and how much do we have?

e09.    What is succession?

e10.    Why do organisms become extinct?

e12.    Where are tropical forests?

e14.    What are the basic components of life?

e15.    What was early life like?

e19.    What materials can cause water pollution?

e23.    How is soil important to plants?  

g08.    What are the spheres that make up the earth?

g09.    What is the interior of the earth like?

g10.   What are earthquakes?

g11.    What is volcanism?

g12.    How are mountains built?

g16.    What is matter?

g17.    Is some matter more useful than other matter?

g20.    What is the theory of plate tectonics?

g22.    What is soil? 

g23.    What are some characteristics of soil? 

g24.    How does soil move?