Page 261 - Environment: The Science Behind the Stories

1. Improved soil conservation measures reduced erosion in 2. Calculate the amount of topsoil hypothetically saved by
the United States by 35% from 1982 to 2003. If additional the additional conservation measures in Question 1, and
measures were again able to reduce the current rate of record your answers in the fourth column of the table.
soil loss by this percentage, the ratio of soil lost to grain 3. Define a “sustainable” rate of soil loss. Describe how you
harvested would fall from 5:1 to 3.25:1. Calculate the soil might determine whether a given farm was practicing
losses associated with food production at a 3.25:1 ratio, sustainable use of soil.
and record your answers in the third column of the table.

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