Why can desert regions be reforested?
Deserts are naturally occurring biomes, they may look lifeless but there are plenty of plants and animals that make a living in desert regions. There’s no reason for people to try to change that. At any rate I’d doubt that humans could make a self sustaining forest in the desert, there’s just not enough rainfall to support the needs of large trees. Over (geologic) time as the global climate changes and land masses shift a desert may become a forest and a forest may become a desert (I think there’s evidence that the Sahara was once forested).
