In the End

• If people keep on eating and multiplying and farmers keep on tilling and harvesting as today, the imperative of food will take another tenth of the land, much from Nature. So farmers work at the hub of sparing land for Nature.
• Calories and protein from present cropland would give a vegetarian diet  to ten billion. A diet requiring food and feed totaling 10,000 calories for ten billion, however, obviously would exceed the capability of present agriculture on present cropland.
• The global totals of sun   on land,  in the air,  fertilizer,   and even water   could produce far more food than ten billion need.
• By eating different species of crop and more or less vegetarian diets people can change the number who can be fed from a plot. And large numbers of people do change diets.
• Encouraged by incentives, farmers use new technologies to raise more crop per plot and more meat and milk per crop, keeping food prices down despite rising population. Differences in yields among nations and between average and master farmers continue showing that yields can be raised more.
• Foreseeing the future demands seeing through fluctuations   in crop production.
• For each ton of production, growing more food per plot lessens the fallout,    for instance, of silt and pesticides, into the surroundings. If several limiting factors are improved together, even adding water and fertilizer can diminish fallout.
• Although the uneven distribution of water among regions and its capricious variation among seasons plague farming, opportunities to raise more crop with the same volume of water kindle hope.
• In Europe   and the United States, rising income, improving technology,   and leveling populations--which all nations aspire to--elicit forecasts of shrinking cropland.
• So by harvesting more per plot, farmers can help ten billion spare some land that unchanging yields would require to feed them. Glimmers can be seen even of changing diets,   never-ending research, encouraging incentives,   and smart farmers feeding ten billion at affordable prices while sparing some of today's cropland for Nature.