Bad agriculture or animal overgrazing destroy the ecosystem and land, there is no winner in the end. Destroy your environment, you are on a self destructive slipping slope. Why did we do it? Because we were ignorant, we didn’t know, we didn’t make the connection. Science is totally relevant here, no that is an understatement, pivotal it is. This man, one man on a mission, has made so much impact, changed so many places to the better. It touches me deeply and amazes me. Check out the documentary. http://www.youtube.com/watch?v=YBLZmwlPa8A and here is the website http://www.whatifwechange.org/magazine/
We have an example right at home here at Ontario in a much smaller scale – top soil erosion via bad agriculture practice. Cheltenham Badlands https://plus.google.com/105442778529509223049/about?gl=ca&hl=en. I was there out of frivolous curiosity two years ago.