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Saturday, March 19, 2005

Population and Sustainable Development (1 of 2)

by Herman E Daly

from his Beyond Growth (Beacon Press, 1996)


The eventual necessity of a steady-state population has been evident to many for a long time. What holds for the population of human bodies must also hold for the populations of cars, buildings, livestock, and each and every form of physical wealth that humans accumulate. In an empty world the population of people is complementary with the various populations of wealth. But in a full world they tend to become substitutes because they compete for the same space and maintenance throughput of low-entropy resources. It is the total resource flow (the product of population times per capita resource use) that is limited. In a world operating at full resource capacity, more of one factor (human population) means less of the other (artifacts).

Even before this point is reached, more people means more consumption, less investment, and slower growth, thus making it more difficult for poor countries to increase per capita wealth. Also, what most attracted my attention while living in Northeast Brazil in the late 1960s was the effect of class differentials in fertility upon the distribution of income. Fertility in the lower class was over twice that of the upper class - a condition that still obtains in many parts of the world today. The possibility of wages ever rising in the face of a virtually unlimited and rapidly growing supply of labor was nil. The rich got richer while the poor got children. An effective upper-class monopoly on the means of limiting reproduction was added to the traditional monopoly on ownership of the means of production to give an additional dimension of class dominance. It seemed to me that the social factors generating poverty were two: nonownership of the means of production (Marx); and nonownership of the means of limiting reproduction (Malthus). Although Marxists and Malthusians are traditional enemies, it seems to me that their respective understandings of the causes of poverty are logically consistent, however psychologically and ideologically at odds they may be. I wrote two papers on this theme. <1> Chapter 9, below, is a sequel. Chapter 8, on carrying capacity, grew out of my work at the World Bank, in response to intensely practical but scrupulously avoided policy questions in Paraguay and Ecuador. These two chapters are in the nature of case studies, and therefore they are a bit more empirical than the rest of this book.

It is frankly discouraging to see how little the population discussion has advanced during the last thirty years. The Chinese have finally gotten serious about population, at least for a while, but only after having grown well beyond a billion people. Instead of receiving applause and understanding from other countries for facing up to the problem, they mainly get unmeasured criticism for a few reported human rights violations related to population control. Certainly they should be criticized for any violations of human rights (most of which are unrelated to reproduction), but too often the issue of human rights is used to avoid the necessity of population control itself. There is apparently no human right to be born into a country that is not already overpopulated. Were such a right to be recognized, it would imply a correlative responsibility not to overpopulate the country. Heightened sensitivity to reproductive rights seems to have dulled our sensitivity to reproductive responsibilities.

National populations grow by immigration as well as by births. Some Chinese are now claiming refugee immigrant status in the United States on the grounds that a basic human right, reproduction freedom, has been denied them in China. They now want to practice reproductive freedom here. And many US libertarians, as well as authoritarians of both the Catholic and the Protestant right wings, are quite eager for them to do so!

At the same time, both setting immigration policy and enforcement of existing laws to stop illegal immigration are becoming hot political issues, especially in California and Florida. Recent welfare cutbacks have made poor citizens of this country increasingly unwilling to share these benefits with illegal aliens, the very same people who are competing for their jobs and thus lowering their wages. This has created both an understandable resentment toward lack of government enforcement of our immigration laws and an unfortunate hostility toward some immigrants.

Failure of the US federal government to adequately enforce its own immigration laws is increasingly, and correctly, seen as an implicit cheap-labor policy - a way to undercut union power and to increase global competitiveness by lowering domestic wages. It is politically difficult to openly defend a low-wage policy. It is much easier to attain the same result indirectly, by turning a blind eye toward illegal immigration (or, in the case of Brazil, toward the rapid natural increase of the laboring class). In addition to lower wages, other sacrifices made on the altar of global competitiveness include social insurance, workplace safety standards, and environmental protection standards. The problem of a global standards-lowering competition is discussed in Part 5, but for now the causative role of both differential fertility and net immigration in supporting an implicit cheap-labor strategy needs to be noted.

Chapter 8

Carrying Capacity as a Tool of Development Policy:
The Ecuadoran Amazon and the Paraguayan Chaco

The remaining sparsely inhabited portions of the world (polar regions, deserts, tropical rain forests) have been "saved for last" for good reason. They are difficult to inhabit and have low average carrying capacity for human activities. Sparse populations are all that have ever been sustainably supported by the ecosystems of such areas. The concept of carrying capacity is an indispensable tool for planning the rational use of these areas, as has been demonstrated by Phillip M Fearnside in his Human Carrying Capacity and the Brazilian Rainforest ( 1986) and earlier by G Ledec, R Goodland, J Kirchner, and J Drake, in their paper "Carrying Capacity, Population Growth, and Sustainable Development" (1985). Here I will supplement these two works by showing how in two specific cases even very simple and crude estimates of carrying capacity can have significant policy implications.

For humans the calculation of carrying capacity is far more complex than for other species. Other species have "standards of living" that are constant over time (animals and plants do not experience economic growth, although consumption may vary over the life cycle). Also they have relatively uniform "standards of living" (that is, per capita resource consumption levels) throughout their populations at a given point in time (no class inequality, with a few exceptions such as social insects whose class structure is genetic rather than social). And the technologies of other species are also relatively constant - genetically given endosomatic technologies that have coevolved with the environment and are consequently well adapted to it. Furthermore, the level of "international" or inter-ecosystem "trade" among animals is relatively constant and limited. For humans these four constants become variables. The calculation of human carrying capacity requires, therefore, some assumptions about (1) living standards, (2) degree of equality of distribution, (3) technology, and (4) extent of trade. As these four variables change, carrying capacity will change. But the concept remains useful because these four variables do not change discontinuously, unpredictably, or beyond all limits. There is inertia and there are ultimate limits.

One need not and should not try to prove that the Ecuadoran Amazon or the Paraguayan Chaco will never support more than x number of people. Never is a long time. It is sufficient for policy purposes to argue that it is very unlikely that within the next generation (twenty-five years) Amazonia could support more than x people living at the average Ecuadoran standard, using known technologies available to Ecuador, assuming Ecuadoran patterns of wealth distribution, and paying for all imports to the region with current exports from the region. A similar statement holds for the Paraguayan Chaco.

Is it possible to make a back-of-the-envelope, order-of-magnitude calculation of x as specified in the preceding paragraph? It is argued below that this is indeed possible, and that for the two regions under consideration very important conclusions for development policy follow from a simple comparison of carrying capacity with population projected over a generational time frame. Ecuador will be considered first, then Paraguay.

The Ecuadoran Amazon

A simple approximation to an extreme upper bound of carrying capacity for the Amazonian region can be gotten by assuming that all of Amazonia could have the same population density as Ecuador as a whole. Amazonia has about 132,000 square kilometers and Ecuador as a whole has a population density of thirty persons per square kilometer. This gives 3,960,000, or roughly four million, people as an estimate (overestimate) of x in the preceding paragraph.

How many people might the Amazon be required to support in the next generation? At the current 2.8% growth rate, the population of Ecuador will double from ten million to twenty million in twenty-five years (one generation). The rural areas of the sierra and the costa are already experiencing net emigration due to demographic pressure, ecological deterioration, and droughts. Aside from the cities this leaves only the Amazon as the area of net immigration. Five provinces in the sierra and costa (Bolivar, Chimborazo, Loja, Manabi, and Carchi) have actually experienced population decline (net emigration greater than natural increase) between 1972 and 1982 (Landazuri and Jijon 1988). Just the additional ten million natural increase represents 2.5 times the extreme upper limit of Amazonian carrying capacity! Even if one were to count nonrenewable petroleum reserves as a part of Amazonian carrying capacity, it would make no difference in the fundamental dilemma since these reserves will be thoroughly depleted over the next twenty-five years. Proven reserves will be depleted in less than ten years, and proven plus probable reserves in less than twenty years, assuming 1988 annual extraction rates (World Bank 1988).

In the face of such a population increase any policy of protecting the Amazon by limiting colonization is doomed to failure. How can any government tell millions of poor people that their survival is less important than the survival of trees and birds and undiscovered species? Even if one believes that ethically it is better to save carrying capacity than individual lives, it would still be politically impossible to resist such colonization pressures. And the poor might well reason that if conservation is worth more than their lives then it is also worth more than the wealth of the rich. Demands for redistribution would increase. The rich, knowing their own interests, will also urge opening of the Amazon to temporarily postpone the pressure for redistribution. With ten million extra people in the next twenty-five years there is no hope for saving the Ecuadorian Amazon from destruction, or of avoiding a great deal of misery.

The above is the foreseeable outcome of present trends projected one generation. This outcome is well within the expected lifetime of the average Ecuadoran now living. What policies might avoid such an impasse?

Consider the following outline of an alternative scenario.

1. Serious and radical birth control policy, beginning with family planning incentives, but eventually moving to real population control. Perhaps it would be possible to cut the increase from ten to five million in the next twenty-five years, and then down to zero growth in the following generation. Even with strong efforts this will take time.

2. To buy time to bring about population control, and to absorb the unavoidable increment of at least five million, strive to increase carrying capacity by the following means.

a. Land reform. Use best agricultural land for food crops rather than cattle. Human carrying capacity can be increased by eating lower on the food chain, and by using the best valley land for agriculture and the hillsides for grazing - the opposite of the present pattern. Intensification of agriculture (irrigation) may offer some scope for raising carrying capacity as well.

b. Redistribution. Redirect resources to vital consumption and away from luxury. High sumptuary taxes with revenues invested in production of basic goods would be one way of doing this.

c. Reinvest petroleum rents and other nonrenewable surpluses in renewable resource development: reforestation, land reclamation, fisheries, et cetera. In general seek to balance the rate of depletion of nonrenewables with the rate of creation of renewable substitutes.

d. Exploit that part of Amazonia that is suited for sustainable agriculture, and keep the rest in its natural state, allowing only sustainable hunting, fishing, gathering, ecotourism, and scientific research.

Such a radical program could only be carried out by a nation that clearly perceived its alternatives as national survival versus national liquidation. That is clearly not the perception of the government of Ecuador, or of the majority of its citizens. Even the leading environmental organizations in Ecuador, dedicated to preserving biodiversity in the Amazon, have evaded taking any serious stand on the population issue. Yet in twenty-five years Ecuador will be another Haiti if present trends are allowed to continue. Not only does the Ecuadoran government not realize this, neither do the multilateral development banks. A nation in the process of environmental liquidation will not be able to pay back loans at interest - it is simply not creditworthy. Ecuador needs some writing down of past debt, not new debt, unless the new debt is invested much more sustainably and productively than hitherto. But reduction of past debt cannot be expected as long as any part of petroleum rents are used for consumption rather than investment in renewable alternatives. Unless Ecuador sees its situation as drastic and takes radical action on its own it cannot expect radical action by others in its behalf, no matter how much the facts may justify the need to write down its international debt. Those same dire facts also justify drastic actions by Ecuador to assure its own survival. Unless economic development and finance agencies inject urgency and more vision than at present, then Ecuador is unlikely to take serious action.

Perhaps one reason Ecuador does not perceive its situation as drastic is that the development banks are eager to lend it more money. The obvious conclusion for Ecuador to draw is that since it is creditworthy in the eyes of the development banks, things could not really be so bad. The development banks think things must not be so bad because Ecuador is willing to borrow at interest and obviously considers itself creditworthy without drastic policies. Each party takes comfort from the other's optimism. Neither party has yet faced the facts.

In order to avoid facing the facts a number of thought-stopping myths and slogans are sometimes invoked. One is that the Amazon is a vast inexhaustible source of wealth and fertility - a latter-day version of El Dorado. This is simply wrong. Another is that technology will save the day. But what specific technologies (in the next twenty-five years) are envisioned? Nuclear power and the "green revolution" have proved disappointing. Biotechnology and nontraditional export bonanzas are the currently advocated technical fixes. But specifically what kinds of biotechnology could contribute specifically what kinds of products in the next twenty-five years? And what nontraditional exports, other than cocaine, could make a difference over this time period? Cut flowers and kiwi fruits flown to the US market will not even make a dent in the problem.

A policy of birth control is often dismissed on the grounds that Ecuador is a Catholic country. But so is Italy, and it has a low birthrate. The Catholic church, although clearly an obstacle, nevertheless urges responsible parenthood, and does not deny arithmetic. Some demographic transition enthusiasts believe that birthrates fall only after industrialization has occurred. But this is contradicted by the demographic history of France and other countries. Certain economists (Julian Simon) even believe that demographic pressure is a positive force in development and therefore that population growth should be encouraged. Such myths find a ready market among policy makers unwilling to deal with the twin taboos of population control and income redistribution. But if Ecuador does not dispell these taboos it will not be a viable country, it will not be creditworthy, and loans from the development banks will not be repayable. Even the transfer represented by unpaid loans will likely do more harm than good by extending the illusion a bit longer.

Since population control is the sine qua non of sustainable development, for Ecuador it is important to look at current fertility patterns to get some idea of how much scope there is for fertility reduction by voluntary means. The most salient fact about this pattern is that for women with no education average completed fertility is 6.4 births, while for women with university education it is 2.3 births. In other words, the fertility of the lowest social class is almost triple that of the highest class (CEPAR 1988). This class difference is much greater than the rural-urban difference (4.1 births for urban women, 6.1 for rural), although the latter is also significant. The point of these comparisons is to show that birth control is already practiced by the upper and urban classes, and that what is lacking is a democratization of birth control - both attitudes and techniques. The democratization of attitudes will require a real democratization of opportunities as well - especially
education and job opportunities for women, as emphasized at the Cairo Population Conference.

The relatively high rate of reproduction of the lower class insures an "unlimited" supply of labor at low wages which promotes inequality in the distribution of income. Far from being a repressive policy, birth control serves to spread to the lower classes the attitudes and practices of the upper class. A lower birth rate tends to equalize the distribution of per capita income, in two ways; (1) it reduces the number of heads among which a wage must be shared in the short run, and (2) it permits the wage to rise by moving away from an unlimited supply of labor in the long run.

Of women having two children only 38% desired to have more; of women having three children only 20% desired to have more; and of women who have four children only 8.5% desired to have more. For all women on average the desired number of children is three (CEPAR 1988, pages 74, 89). Yet completed fertility for all women in Ecuador averages 4.3. Some 35% of all births in Ecuador in the last five years were either not wanted or not wanted at that time (ibid, page 89). Clearly the first step in population control is the voluntary elimination of unwanted fertility, which would have a significant demographic effect as well as providing a basic human right to the lower class - one that is already enjoyed by the upper class. Birth control is therefore not politically unrealistic, in spite of dogmatic opposition from both the Catholic right and the Marxist left.

The Paraguayan Chaco

Paraguay's greatest environmental advantage has been its small population (some three million in 1982, and close to four million today). At the current 2.5% annual rate of population growth (doubling time of twenty-eight years, or slightly more than one generation) this advantage is rapidly disappearing. Furthermore, this environmental advantage has historically been considered as an economic disadvantage. Demographic factors are exacerbated by the fact that all public lands available for colonization have been distributed. In the future land cannot be made available to some without taking it away from others. Also, the fractionating of landholdings into uneconomic minifundia is driven by population growth and the practice of equal inheritance.

There is very little concern about population growth. Traditionally the goal has been to increase the population by bringing in colonists to settle the land. After the disastrous War of the Triple Alliance, Paraguay was left, in 1875, with only about 220,000 people. It is therefore understandable that pro-natalist views should still be dominant. The question for the next generation, however, is, Where will the four million additional Paraguayans live and work? Since 98% of the population lives in the eastern half of the country, that leaves the western half(the Chaco) as the obvious place. As just mentioned, land is becoming scarce in the east, and land conflicts have already become violent. Furthermore, an FAO study concluded that "the agricultural frontier has already exceeded the limits of desirable development in most of the Eastern Region", and that continued expansion would be profoundly destructive of the ecosystem (PNUD 1979). In 1979, when this statement was written, Paraguay had about three million people, and now has close to four million, all but 2% of whom still live in the east.

There are no official estimates of human carrying capacity of the Chaco, or of the east either. Government officials speak of five million or twenty million people in the Chaco of the future, and at the same time state that the agricultural future of the country is in the Chaco. They have not thought in terms of carrying capacity over the next generation. What, then, is a reasonable estimate of carrying capacity for the next generation?

An upperbound estimate can be gotten, as in the case of Ecuador, by assuming the Chaco could be populated to the same density as the east. The population density of the east is 18.6 persons per square kilometer, and the area of the Chaco is 247,000 square kilometers, giving a product of4,594,000 people. Most people agree that this is an extreme overestimate for any foreseeable future. But it serves to rule out of court any talk of absorbing more than five million people in the Chaco, and that is an advance over the current level of discussion.

It is possible, however, to get a much better estimate using the actual experience of colonists in the Chaco. This would have been desirable in the case of the Ecuadoran Amazon also, and would probably have led to a much lower estimate, but such information was not available. The Mennonites have the most successful colony in the Chaco. We can take the Mennonite population density and generalize that to the entire Chaco. In 1987 there were 6,650 Mennonites living on 420,000 hectares, giving a density of 0.0158 persons per hectare. Multiplying that by 100, the number of hectares in one square kilometer, gives 1.58 persons per square kilometer. That density times the total area of 247,000 square kilometers gives 390,260, or roughly 400,000 persons, not even half a million!

Although still crude, it is obvious that the second estimate is more realistic. But the Mennonites themselves have unused land and estimate that they could support twice their present numbers if they used all their land, which they will have to do in thirty-five years if they maintain their 2% growth rate. So perhaps our estimate should be 800,000. Also, the Mennonite standard of living, though hardly luxurious, is above the average for Paraguay, so a few more thousands could be supported by lowering per capita consumption levels to the national average, even though this goes against the basic notion of development.

On the other hand, our calculation implicitly assumed that the Mennonites have average Chaco land, when in fact it is better than average. The calculation also assumes that other settlers during the next generation could do as well as the Mennonites. This is doubtful for several reasons. First, the Mennonites brought with them the peasant traditions of Europe, which are absent among Paraguayan colonos. They also had a strong community of mutual aid and support, as well as outside help from European and American Mennonites. Furthermore, it took them over two generations (sixty years) of hard work and sacrifice to reach their present level. All things considered, even half a million may be an overestimate, especially if ranching rather than agriculture turns out to be the best use of most Chaco land, as seems likely.

Since water rather than soil quality seems to be the limitative factor, one naturally thinks of large irrigation projects as a way of increasing carrying capacity. However, the Mennonites are extremely skeptical of irrigation in the Chaco because they are convinced that it would lead to salinization of the soil (raising the level of existing salt closer to the surface and within reach of plant roots).

The low population density of the Chaco makes it the "obvious" place to put the four million new people. Putting them in the east would sharpen land conflicts and require redistribution. The stage is set for an expensive settlement program of the type witnessed in the Brazilian Amazon. The likelihood of failure due to ecological reasons is very high. Politically the colonization of the Chaco will probably be seen as the way to minimize already serious land conflicts in the east, postpone dealing with population control, and maintain temporarily the mirage of progress and optimism, as well as offer a great national project to galvanize public support. Against such political advantages the sobering calculation of carrying capacity may not be very persuasive. Elements of a realistic policy for Paraguay would not be very different form those listed for Ecuador.


In both cases, the simple estimate of carrying capacity has served to clarify the gravity of the situation. Although the calculations are simple and crude, the inferences made from them are quite robust because the conscious tendency was to err on the high side in estimating carrying capacity. For policy purposes refined econometric models would add little to what is already obvious. What is lacking is not more exact information, but the political will to respect the ecological reasons for the historically low population density, whether in the Ecuadoran Amazon or the Paraguayan Chaco, and to limit human populations accordingly. The fact that human carrying capacity is not constant in no way removes the serious rate and magnitude contradictions over the next generation in the two cases here considered. Nor does the "Hong Kong solution" of importing food for a dense population by exporting manufactured goods and financial services seem realistic for either the Ecuadoran Amazon or the Paraguayan Chaco. For one thing, the regions are remote. Also, the limited niche for food importers in the world economy is rapidly filling up.

Attempting the impossible will waste unlimited amounts of resources and cause much conflict. The first rule of development policy therefore should be, "Do not attempt the impossible". The first operational corollary of this rule is, "Respect carrying capacity".

None of this is meant to imply that carrying capacity is only relevant to developing countries. If the United States of America had worried about carrying capacity, it would not have become so dangerously dependent on depleting petroleum reserves belonging to other nations. If the United States cannot even pass a reasonable gasoline tax to discipline unsustainable consumption, is it realistic to expect Paraguay and Ecuador to control population? Both actions may appear politically unrealistic in the short run, but not taking such actions is biophysically unrealistic in the long run, even where "long run" means only twenty-five years.


1. Herman E Daly, "The Population Question in Northeast Brazil: Its Economic and Ideological Dimensions", Economic Development and Cultural Change (University of Chicago, July 1970); and "A Marxian-Malthusian View of Poverty and Development", Population Studies (London School of Economics, March 1971).

Bill Totten


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