By 2050, the world will host nine billion people—and that’s if population growth slows in much of the developing world. Today, at least one billion people are chronically malnourished or starving. Simply to maintain that sad state of affairs would require the clearing (read: deforestation) of 900 million additional hectares of land, according to Pedro Sanchez, director of the Tropical Agriculture and Rural Environment Program at The Earth Institute at Columbia University.
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