The soils in large areas of the Southern Hemisphere, including major portions of Australia, Africa and South America, have been drying up in the past decade.

The soils in large areas of the Southern Hemisphere, including major portions of Australia, Africa and South America, have been drying up in the past decade.
More than 400 dams produce power and control floods in the nation’s fourth largest river basin. The U.S./Canada treaty that established responsibilities for water flow and power sharing is due for renewal.