ABSTRACT
Land, considered as planetary surface, is essential to the sustenance of life, for it is earth’s surface that receives the solar radiation that energizes photosynthesis, which in turn provides food for plants and animals, including human beings. Each individual person (along with individuals of other species) can survive only by having access directly or indirectly to the area of land surface required to produce enough photosynthetic product to nourish that individual, either immediately or by nourishing the plants or animals upon which it feeds. Because the planet’s surface is of a fixed size, the area available to feed each person is limited and, in effect, is becoming smaller and smaller as the human population continues to grow, as the productive capacity of land is degraded, and as land surface is diverted to uses other than pasture and food-crop agriculture-the methods whereby human beings now gain most of their sustenance.
