This presentation has been going around the "Permaculture World" for the last month. It is amazing. This is a must watch video if you have any interest in repairing our broken ecosystems.
From the TED website:
“Desertification is a fancy word for land that is turning to desert,” begins Allan Savory in this quietly powerful talk. And it's happening to about two-thirds of the world’s grasslands, accelerating climate change and causing traditional grazing societies to descend into social chaos. Savory has devoted his life to stopping it. He now believes -- and his work so far shows -- that a surprising factor can protect grasslands and even reclaim degraded land that was once desert.