The Maowusu Desert was created in the last century due to desertification, mostly began to erode in large amount from 1950s-1980s due to heavy industrialization, so if anything this is like a green reconquest, now birds and other seasonal animals are coming back.
Great idea too, wiping out deserts will help stop the spread of desertification from climate change. I remember reading about how China has some of the most desertifiiable land out there and making new forests at strategic locations will help tons.