Another article to go with this:

http://inhabitat.com/shanghai-is-planning-a-massive-100-hectare-vertical-farm-to-feed-24-million-people/

As Shanghai continues to expand outward, replacing agriculture with urbanization, a US-based design firm is looking to reimagine the way that Shanghai grows food to feed its 24 million people.

The Sasaki planning and urban design firm is turning heads with its masterplan for a 250-acre urban agricultural district in Pudong called Sunqiao, which will include, most spectacularly, towering vertical farms that grow lots of leafy vegetables.