Really interesting piece, but the end falls short. I would have loved to see concrete solutions and possible implementations. It felt like the article was building up to that.
This 'Greening the Desert' projects shows a promising way forward using long term (5-8 years) permaculture techniques to render arid, salty and previously unproductive land into productive land able to capture and sustain the majority of the water it needs with minimal irrigation.
http://permaculture.org.au/2007/03/01/greening-the-desert-no...
I recommend watching the videos, truly inspiring stuff. The original greening the desert project transformed an arid, salt ridden area in Jordan into a fruit producing farm within a few years. The locals laughed initially at their efforts but then started queuing up to learn how it was done.
The other thing we need to do (in the West) is appreciate the value and privilege of eating meat and stop expecting to base a large part of our diets on it. A given amount of land can feed 7x the number of people when used to grow plant crops eaten directly as opposed to feeding it to livestock.