Abstract: Disjunction market surpluses of food and worldwide nutritional shortfalls appears to be symptomatic of underlying vulnerabilities, raising questions about the sustainability of agricultural production.
When is "surplus" less than plenty? How is it true that, "Due to advances in agriculture of many countries, there is now a substantial world surplus of food" (Abelson, 1987) while at the same time more people than ever before are undernourished or malnourished (Chandler, 1985; Wortman, 1980)?
"Surplus" in the sense that buyers do not exhaust supply at any price acceptable to sellers is standard usage in economics. With food, the term denotes that a few countries have become net exporters of certain food-stuffs around which there is intense sales competition on the world market. While this is an important consideration for American agriculture, which produces many of those foodstuffs and competes on the world market, it says nothing about whether the world's growing human population can be adequately fed by any likely increases in food production. Used in connection with world population, world carrying capacity, or sustainable production, "food surplus" is misleading or worse. Unfortunately, the erroneous connection is widely made (see Abelson, 1987).
Only from the producers' point of view is there surplus. From many potential consumers' standpoint there is shortage. Some go hungry even in countries that are net exporters of food (Poleman, 1975). There is surplus largely because millions of malnourished persons do not have the financial wherewithal to create an economic demand sufficient to acquire a nutritionally adequate share (Street et al., 1980; Wortman, 1980). For example in India, a Green Revolution "success" story, the National Institute of Nutrition estimated that as many as 50% of rural households and 55% of urban slum households do not have enough food to meet daily energy requirements (India's Farmers, 1988).
The real costs associated with producing the market surplus suggest that far more than a distributional problem is involved. "New and better crop varieties" are cited as the most important factor in the increase in world food supplies (Abelson, 1987). Yet these new strains require expensive and nonrenewable resource impute. Besides being expensive to produce, the new varieties have themselves contributed to poverty and malnutrition in third world populations through changing labor and landholding patterns. Finally, yields may not be sustainable, and the crop monoculture associated with new varieties is not without risk.
The introduced crops and accompanying technology may destabilize countries because they are most successfully adopted by wealthier landholders and tend to widen the gap between rich and poor agriculturalists. Large aggregations of land are required for efficient mechanization, and the new grain varieties depend upon expensive petroleum-based inputs that only wealthier farmers can afford. The cost of fertilizer, pest control agents, and fuel for irrigation systems and other farm machinery ultimately depend on world oil prices (Wade, 1973; 1974b). (Coal is not foreseeably substitutable for most agricultural uses of oil, so significantly higher prices will reflect the shrinkage of oil reserves that will almost certainly become apparent within the next decade (Gever et al., 1986).)
The initially greater return from the new crop varieties tends to drive small producers of vegetables and other traditional foodstuffs off the land. Peasants, become landless, no longer can practice subsistence agriculture, and their cash earnings as agricultural labor barely support a family in good times; in years of natural calamity, such as drought, jobs vanish and food prices rise beyond reach of this sector of the populace (Poleman, 1975; Street et al., 1980; Wade, 1973; 1974b).
Once large agricultural units are established, it is usually more profitable to concentrate on a few crops that lend themselves to export. Especially when these are produced close to markets, which is to say, close to more urbanized areas, export crops are highly visible and contribute to the misconception that there is abundance in the hinterland.
The fact of such exports does not signify that there is surplus food from a nutritional perspective Evade, 1974b). Indeed, the reverse may well be true; foodstuffs for local consumption may not at all be adequate for the population involved. The production of traditional food that formerly was sold locally is often reduced or disappears as foreign exchange-earning crops replace subsistence agriculture (Curtin, 1985). Moreover, and even if the local populace could afford to buy it, the export crop is probably less nutritous as a single, dietary staple than the mix grown on the traditional subsistence farm Wade, 1974c). Thus, it is somewhat misleading to imply that new strains have raised world farm productivity in general, or that the surplus is available to or constitutes adequate nutrition for the local population of the producing country.
Bifurcation of the society into a more modernized economy centered around major cities and ports, and collapsing, backward rural areas is a further consequence of concentration on the export sector. The disparity in land values between urban periphery and hinterland is exaggerated by often-poor rural distributional systems. Differential access to health care, educational facilities, and jobs is compounded by high fertility and promotes rural to urban migration at rates higher than the economy can absorb. Once collected in politically-sensitive population centers, unemployment and poverty generate pressure to further increase production (Eckholm, 1975; Wade, 1974b).
Bringing more land into production is widely accepted as an appropriate and ostensibly costless response. However, the ramifications are in fact complex and often mean that not only that producers of less profitable foodstuffs have been displaced but also that land has been converted from a sustainable use to one that degrades the soil. Examples of overuse of unsuitable lands include cultivation of unterraced hillsides, reduction of fallow periods in rain forests, and intensive pasturage in dry, mountainous, or poor soils. Both semi-arid regions and tropical rain forests are ecologically delicate. and environmental degradation ultimately reduces carrying capacity for both flora and Jauna (including Homo sapiens) below the original sustainable level (Brown, 1975; 1984; Eckholm, 1975; Holdren et al., 1980; Walsh, 1988).
Such adverse ecological effects were realized in the 1930s dust bowl in the United States and are equally evident in the arid African Sahel and the tropical rain forests of South America and Asia. For example, the poor soil base in large parts of the Amazon and Orinoco drainages lends itself to intensive cultivation and extensive fertilization over the short term only. Within a few years of large-scale clearing, some soil types turn to hardpan, or laterite. Others are too poor to support intensive cultivation without intensive fertilization. Others become weed-choked but cannot be intensively cultivated because of cost or situation on hillsides subject to erosion. The net result of attempting to intensify agriculture in such regions is a greatly degraded resource available to the local population (Holdren et al., 1980) as well as a reduction in the amount of rain forest available to maintain the ecological balance of the world as a whole (Marland,1988; Lewin,1987).
Cultivation-fallow rotation (swidden gardening) appears to be the highest sustainable use of many tropical rain forests. With fertilizer and introduced vegetation for weed-control, the fallow period can be shortened but not eliminated (Sanchez and Benites, 1987). Swidden technology supports low density populations on marginal land; cleared for intensive cultivation or grazing, that land soon supports almost no one. (Brush, 1975; and see Russell, this issue).
Even in areas suited to intensive agriculture, certain characteristics of the new crop strains exact long-run costs. Row crop cultivation speeds top-soil loss, particularly in windy or hilly areas (Brown, 1984). The new strains often deplete the soil with extreme rapidity and so also require heavy application of chemical fertilizers based on nonrenewable resources such as petroleum (Revelle, 1980; Gever et al., 1987). Fertilizer-intensive cultivation itself removes humus which, if not replaced, turns the soil to sand. Irrigation further increases dependence on nonrenewable and usually imported energy inputs (Holdren et al., 1980). As supplies of nonrenewable resources decrease and are subject to competitive alternate uses (for example, the synthetic material, fuel, and heating oil uses of petroleum), a growing population faces scarcity of the energy and other inputs required to maintain the production of the new strains of food crops upon which it depends (Walsh, 1988; Wall, 1988; Hirst, 1974; Wade, 1974c; Chancellor & Goss, 1976; Gever et al., 1987).
Fertilization and irrigation create other problems, including salinization, watertable depletion, fertilizer run-offs, and environmental pollution such as that increasingly experienced in California's Central Valley. Increased use of pest control chemicals also is detrimental to wildlife and people living in agricultural areas (Holdren et al., 1980; AAAS Office of International Science, 1977).
The experience of famine areas highlights the fragility of the world's ecology. Relief through the importation of large quantities of "exportable food" from other areas of the world brings immediate reduction in hunger; but such aid does nothing to establish or revitalize existing local food production or ecosystems and may indeed further dislocate whole communities (Wade, 1974a). Not only does the stream of imported food-stuffs often disrupt what customary local production is available, creating long-term dependence; more dangerously, it may encourage a spurt in population growth in an area where carrying capacity cannot support it beyond even one generation.
A further element of risk is that, although new crop varieties have indeed increased productivity per acre, they are also introducing a degree of genetic uniformity in any given crop category that can be extremely dangerous in the long run. Crops that formerly varied from relatively small area to relatively small area now have become genetically uniform over very large areas, even worldwide (Wilkes, 1972). Food supply thus becomes extraordinarly vulnerable to climate change, insect or other infestations, or plant diseases; catastrophe associated with a particular genetic strain becomes a matter of worldwide as opposed to local significance (Wall, 1988; Wade, 1972; 1973; Miller, 1973).
Thus, any supposed surplus of food prevailing overall in the world or, more likely, in the export sector, seems barely relevant to the needs of an expanding world population. Fundamental questions must be answered by those who deduce world carrying capacity from market surpluses. For example, how is even the present level of food production to be sustained, given side-effects including degradation of soils, increasing pollution, and dependence on nonrenewable inputs? And, is juxtaposition of surplus and famine, far from being an artificial dysfunction in the distributional system, not a reflection of rising production costs associated with trying to increase and even sustain yields as well as of social structural developments that can be traced to the new technologies?
Population growth threatens to render modern methods inadequate and unsustainable (Ehrlich, 1988). Even in areas such as Indonesia that have adequate petroleum stocks and are heavily committed to modern technologies, production is now lagging population growth. The marginal return from pesticide and fertilizer has decreased. Weekly community-wide rat hunts to reduce rodent populations suggest the urgency of protecting existing food. It appears that the present deterioration of food supplies relative to human numbers may not be reversible. Even delay of a catastrophic collapse is moving beyond reach because funds to support innovation are scarce; laboratories stand empty and field stations have deteriorated (Wall, 1988).
From this perspective, the increasing rate of production of some crops is notable mainly because it is a response to a population phenomenon, viz. that population increase has outstripped traditional methods of producing food. The new strains were developed precisely because of the needs of growing populations. But the availability of such food crops is only marginally beneficial to hungry people, even in nations where that food is produced. The achievement of an ostensible food surplus is illusory and essentially meaningless in terms of world hunger (Brown, 1984).
Thus, the danger is that this illusory surplus will be yet another factor contributing to the pressure that make efforts at meaningful control of population growth extraordinarily difficult, if not impossible. The concept of a world food surplus is extremely mischievous when separated from its intended context: the required economic return to large scale agricultural producers, and the effort of the American producers to be competitive in the export sector of the world food market. Facile references to food surplus most unfortunately divert attention from the fundamental world problem—which is of staggering proportions—that given rates of natural increase from the mid-1980s, the world population doubling time appears to be 40 years (Population Reference Bureau 1985; 1986; 1987).
Food surplus says next to nothing about population carrying capacity or the realities of actual food distribution. Food surplus is a market term; it is meaningful only as a description of supply in "supply and demand" equations. Demand is "effective" only when joined with buying power. The increasing numbers of hungry people of the world remain hungry, despite any economic surplus.
It is not apparent how food production will keep pace with unbridled population growth. Current technologies cannot indefinitely sustain intensification of agriculture. Requirements for increasing energy inputs to maintain any given level of production, depletion of resources, pollution, the exhaustion of fertile land, risks associated with monoculture, and other side effects destructive of the carrying capacity are limiting factors. Reference to a marketplace surplus masks this dilemma.
Sustainable production depends on maintaining the carrying capacity which is a prerequisite to that production. Yet maintenance of agricultural, and indeed, the whole earth's ecological, carrying capacity depends on limiting the human population growth which increasingly impairs it.
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Appeared in Population and Environment, Volume 10, Number 2, Winter 1988. Reprinted by permission of the publisher and the authors.