Population Trends and the World's Resources

Abstract

MY intention this afternoon is to present a broad picture of the relation ship of man's numbers and needs with the availability of biological resources, in the form of food and industrial raw materials, both now and in the near future. I have no new facts to present, but hope that an arrangement of known facts alongside one another will be helpful in providing an appreciation of how we stand. I refer especially to the British Empire and Commonwealth because it contains such diverse lands, peoples, and conditions, and because its welfare is our special concern. Needs, determined by population, are met over a wide field by biological resources. The supply of these biological resources is dependent upon a whole host of factors, some of them favourable, some of them unfavourable. Some of these factors are constant, some of them dynamic in their incidence; some are under our control and some are not. Frequently factors on the bio? logical plane are both accelerative in action and accumulative in result. Many of the factors concerned lie in the zone of overlap between geography and biology. This afternoon I shall deliberately leave aside the problems set by our economic system, in which individual and national need and purchasing power so often seem almost to be in inverse ratio. Biological resources derive from the present growth and reproduction of living organisms, both vegetable and animal. It is axiomatic that for all supplies derived from living organisms there is a particular annual cropping rate which will give the maximum harvest on a sustained yield basis. This is the rational rate of cropping, and departure from it in either direction results, over a period of years, in reduced yields. This principle is of primary import? ance whether we are considering fishing, grazing, lumbering, or the fertility of the soil itself. Area is the most important single factor in production, and the total area available obviously has an upper limit. The biological resources with which we are concerned supply the whole of our food (with such minor exceptions as salt and saccharine) and a large part of our industrial raw materials. Usually food and industrial crops are in com? petition for the same areas of land. For the most part this competition will continue to be inevitable. Sometimes the calls of food and industry compete for the same commodity; for example, fats and vegetable oils. I shall not deliberately lay more stress on either of these two categories, the dietary and the industrial. But in the first part of my argument I shall deal chiefly with the dietary aspect of supply. This is because there is now a moderately wellagreed level of nutrition which is deemed necessary for the individual. There is no similarly agreed level of supply of rubber, timber, fibres, paper, soap, and so on.