| Popis: |
Several assessments have been made which indicate that if adequate inputs are used, the extent of land resources is sufficient to support a world population in excess of 8 billion (Buringh and Van Heemst, 1977; Higgins ct al., 1982; de Vries et al., 1995; Dyson, 1996). There have also been many dire warnings that the methods that must be used to produce the necessary crops will lead to soil degradation and environmental pollution, as a result of which it will be impossible to sustain the present population, let alone a much greater one (Brown, 1988; Ehrlich and Ehrlich, 1990; Myers, 1991; Ehrlich et al., 1993; Brown and Kane, 1995). The most detailed of these various studies is that by FAO, “Potential Population Supporting Capacity of Lands in the Developing World” (Higgins et al., 1982). Although the authors reached the conclusion that the soils of the world were able to support a population in excess of 8 billion, it was also concluded that, in 1976, 19 countries were “at risk” because they will not be able to produce sufficient food for their population in the year 2000, even at “high levels” of inputs; 36 were at risk because they could not do so at intermediate levels; and no fewer than 65 could not do so at low levels, which is all that most of them could afford. The latest estimate of the number of countries at risk at low levels of input is 82. Thus, while the world may not be on the brink of the Malthusian precipice, there are several countries that are. Rwanda, which has the highest population density of any country in Africa, appears to have fallen over the brink. At low levels of inputs, and with population pressure driving fanners to exploit soils, soil degradation and a decline in productivity are inevitable. Thus, there are many who believe that whatever practicable methods are used, it will not be possible to produce the crops necessary to support the world population. Borgstrom (1969), for instance, stated that “the world . . . is on the verge of the biggest famine in history. . . . Such a famine will have massive proportions and affect hundreds of millions, perhaps billions. By 1984 it will dwarf and overshadow most of the issues and anxieties that now attract attention.” The fact that this did not happen, just as the prophets of doom from Malthus on have so far been proved wrong, has led many others to assume that there is unlikely to be a continuing problem of food production, although many continue to predict massive famines in the near future. |
