Esteban Jobbagy, an agronomist at Argentina's University of San Luis kneels before a thin well that he dug with his colleagues. Jobbagy is investigating whether rapid development between the Andes and the Monte Desert, home to 2,000 indigenous Huarpes, is putting pressure on the desert's underground water supply.

The trees surrounding Jobbagy are Algarobbos, which provide a type of bean vital to the local diet.

Adapted to the scarcity of water, the trees roots extend as much as 32 feet (10 meters) below the desert floor.

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