Page 404 - Laboratory Manual in Physical Geology

D. The Sand Hills region now receives an average of 580 mm (about 2 in.) of rain per year, and large active dunes tend to occur

in regions that receive less than 250 mm of rain per year (less than an inch). Winds capable of moving sand already occur in
this region, but the rainfall and moisture from evapotranspiration is presently enough to sustain grasses that hold the sand in
place in the dunes. If you were a rancher in the Sand Hills, what grazing practices would you follow to decrease the risk of
desertification there?

(Courtesy of Courtesy of U.S. Geological Survey)

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E. REFLECT & DISCUSS Many cities in central and eastern Nebraska rely on groundwater for consumption, industry,
and pleasure. As these cities continue to grow, and their use of groundwater increases, what effect might this have on the
environments and people of the Sand Hills?

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