Vertical farmingSkyscrapers in cities for hyper-intensive farming.
Crops grow are expected to be bio-altered/created.
Sounds great...parks are out skyscraper farms in with visitors strolling round them.
see wiki
http://en.wikipedia.org/wiki/Vertical_farming
I expect these will be obsolete pretty soon after rep rap nano machines that can manufacture stuff to order by downloading programs from the WorldWideWeb, and assembling from atom up using stripped down household waste.