http://www.fao.org/fsnforum/cfs-hlpe/water-food-security-scope follow this link and good concepts are explained in relation to the subject matter.

Published February 14, 2015 03:00 by MURALI KOCHUKRISHNAN, IL&FS ENVIRONMENT - SR.MANAGER-PROJECTS (GEOLOGY&HYDROGEOLOGY)

http://www.fao.org/fsnforum/cfs-hlpe/water-food-security-scope follow this link and good concepts are explained in relation to the subject matter.