More than 99% of the world’s food supply comes from the land, while less than 1% comes from : oceans and other aquatic habitats. The continued production of an adequate food supply is directly dependent on ample fertile land, fresh water, and energy.
As the human population grows, the requirement of these resources also increases. Even if these resources do not deplete, they will face a disastrous failure to meet : people's needs and can never be divided among the public equally. Fertile agricultural land is currently going through crises at a shocking rate. The shortage of productive fertile land, combined with decreasing land productivity, is the major cause of current food shortage.
Water is another critical item for all crops. Adequate amount of water is required for the growing session of cultivation. In fact, agricultural production consumes more freshwater than any other human activity. This is the reason why in many countries people are facing continuous shortage of fresh water. With the current world population, there is a high-paced competition among individuals, regions and even countries for grabbing water resources. Water resources, critical for irrigation, are under great stress as populous cities, states, and countries require and withdraw more water from rivers, oceans, and lakes and very little is left for general population.