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Principles for a Sustainable Society

Kien Lai | AG 101 | 6/04/03 | California State Polytechnic University, Pomona

What is a Sustainable Society - Are We One?

A sustainable human society is a concept that is not hard to articulate in an abstract way. It is a society that interacts with its environment in ways that leave the environment free to be used again and again in ways that maintain the integrity and interactions of the biosphere, with little other than short-term change. A sustainable society draws on the resilience of the earth's biological and chemical systems, allowing only those alterations of the environment from which relatively rapid recovery is possible. By relatively rapid recovery we do not mean recovery over geologic time but over human time.

How do present human societies measure up against this definition of sustainability? In the developed areas of the world, where labor, resources, technology, and trade have led to material wealth for many, people are seeking to perpetuate and expand that abundance; they purchase new cars and new homes. The homes spread into the farming regions that once supplied the cities' food. The spread also into the forests and deserts surrounding the cities. The suburbs expand; wilderness becomes asphalt; the trip to work lengthens and more gasoline is consumed. Power plants are built to supply the increasing demand for electricity. Dams are thrown across rivers to store more water to sprinkle on more lawns and to irrigate crops grown in arid regions. Forests are cut to supply lumber for the homes.

And in the developing countries of the world, and in parts of the developed world as well, poorer men and women are seeking material security. They are seeking lives in which food and shelter are more certain and in which their children can survive. They often migrate to the cities, looking for this better life. They may leave farming regions whose land is concentrated in the hands of the wealthy or where their land has played out. They leave when mechanization decreased the number of rural jobs or when the city offers better-paying jobs even when jobs in rural areas are still available. The migrants may settle on the fringes of the nearest cities, in shanty towns in Africa, in Asia, and in South America. With luck their squatter settlements are gradually transformed from tar-paper shacks without water and electricity to more secure dwellings. Drinking water may come first at public standpipes, then at taps in the home; electricity at the house may follow; finally, sewers may be built to carry off wastes.

Around the world, cities are growing rapidly. Twenty-two cities of more than 10 million people are predicted by the year 2000, 18 of them in developing nations. The growth of these cities has profound effects on the environment. Canals divert water from distant rivers to the growing cities. Hydropower dams are built to supply the cities with electricity, and land is drowned, sometimes displacing primitive people from ancestral lands. In other cases the dams rob lowlands of their yearly deposits of rich silt, now trapped within the reservoirs. Autos and trucks pollute the air with their exhausts. Rivers become polluted with human wastes. Migrants who do not head for cities take off into the wilderness to carve out a new life on new soil--as the American pioneers once did.

Growth and development are facts of life in the developing and developed world. And growth and development have serious consequences for the environment, both locally and globally. Are we a sustainable society? Clearly we are not. Thoughtful people have observed the effects of the growth and development of human societies and have sought to alter the cascade of environmentally harmful activities with varying degrees of success. The history with which this book opened, of actions taken to protect the environment in the United States and worldwide, describes the stimulus to action and the results achieved by attacking each problem as it came along.

Now in the 1990s a new idea is being born--in the United States and across the globe. It is only being born, but hope attends the birthing process. The idea is expressed in several ways--as sustainability, as a sustainable society, and as sustainable development. The words have subtle differences. Sustainability is a concept; it is the quality of being capable of continuation, virtually forever. The second term, a sustainable society, is a goal for today's civilization. Native Americans had achieved a measure of sustainability with their pre-Columbian agriculture and hunting societies. Their numbers and practices were such that the ecosystems and resources on which they depended were in no danger of running out. The essays in this book by environmental states people from around the world all deal with ways to achieve a sustainable society in the modern context, using available and soon-to-be available technology, using well-known practices and emerging ideas.

The last term, sustainable development, is a term coming into wide use in the United Nations Development Program and The World Bank to describe the aspirations of these organizations for the development process. The development process refers to such activities as the building of roads and dwellings, the irrigation and farming of formerly wild lands, the provision of safe drinking water, the collection and treatment of wastewater, the removal of solid wastes, and the provision of electricity and fuels. The term sustainable development is both hopeful and misleading, hopeful because it suggests that development often falls so very wide of the mark. This is because there are two forces driving development. One is the need to improve the lives and health of people all around the globe, and the other is population growth.

New population requires new space, new water supplies, new energy sources. New populations must take some toll of the environment. At the same time, that toll can be reduced. Perhaps a better term for what people are calling sustainable development is reduced impact development. This is within the realm of possibility. It can be accomplished by setting aside sufficient land area to preserve ecosystems and by using farming practices that do not lead to rapid soil erosion, irrigation that does not lace the soil with salts, and wind power as opposed to the use of electricity from a coal-fired power plant, and by other means. But the impact of development cannot be reduced to zero.

Components of a Sustainable Society

The important term, the term on which we will focus is sustainable society. We focus on this term because it is clear that it is a goal to be achieved. A sustainable society is a goal for both the developing and the developed world.

A sustainable society has a number of readily identifiable components.

Each is achieved differently, but there are strong connections, as will be seen.

Sustainable Energy Use

A sustainable society uses renewable energy resources. Sustainable use of energy resources cannot be achieved with the fossil-origin fuels (coal, oil and natural gas) because the resources of these fuels are finite. In addition, all these fuels pollute the atmosphere both with short-and long-term pollutants. The short-term air pollutants that injure human health are sulfur oxides, nitrogen oxides, particulate matter, carbon monoxide, and photochemical air pollutants. The same pollutants affect animals as well as vegetation from forest trees to food crops. In this sense the fossil fuels also impact ecosystem stability of both plants and animals. The best we can hope to do, if fossil fuels are used, is to prevent some of these emissions by modifying combustion processes or by practicing end-of-pipe removal by such devices as the catalytic converter on automobiles and scrubbers on power plants.

The long-term air pollutants from the fossil fuels are acid rain and carbon dioxide. Acid rain acidifies both lakes and soils, damaging especially the land and water communities of mountain ecosystems. Carbon dioxide in modest amounts is no problem at all, but in the massive amounts currently being emitted it overwhelms the natural carbon dioxide cycle and accumulates in the atmosphere. many scientists expect this accumulation to lead to a warming of the globe because of carbon dioxide's capacity to trap long-wave radiation that would have escaped from the earth. The consequences of that warming--in all its dimensions, including changes in rainfall as well as temperature--could include effects on food supplies, water supplies, soil and the survival of plant and animal species. In short virtually all of the components of sustainability could be affected. Clearly the fossil fuels, when used in the quantities demanded by a society of 5 to 10 billion people, cannot be the fuels that power a sustainable society.

We must ask then, since the fossil fuels are obviously finite and in other ways inappropriate, why haven't we changed the fuels we choose to use? First, a shift in fuels is a slow process. New technology needs to become generally available, and people to service that new technology are needed. Second, the prices of the finite resources are still so low that people are not choosing to use the renewable and low environmental impact energy sources. The cartel that controls much of the world's oil supply is purposely keeping the price of oil low by high levels of production so that the industrialized countries will not have a sufficient incentive to shift to renewable and other energy sources or to conserve energy in a serious way.

How can society cause a shift to renewables if it does not take immediate economic sense to do so even if it makes long-run environmental and long-run economic sense? How can further effects be made a part of today's decisions? It takes courage to place taxes on the fossil fuels, but if done properly we can induce the shift and not hurt any segment of society. Gasoline taxes can be increased to the levels in Europe, and though this may seem painful, income taxes could be cut so that consumers have as much untaxed income as before. Only their decisions about how to spend that untaxed income would be changed.

Is nuclear energy sustainable in the long run? Resources of the fissionable form of uranium, namely uranium-235, are finite, so light water reactors are not a sustainable energy source. Resources of nonfissionable uranium-238 from which the fissionable plutonium-29 can be bred are much larger. As a power source the breeder reactor, which uses plutonium-239, could last centuries. Nonetheless, the safety issues, the issues of waste disposal and of the spread of nuclear weapons, are all so serious that nuclear energy might make sense only as a temporary solution to the problem of fossil energy consumption. In the long run, only renewable energy resources--wind, solar, and possibly geothermal--are sustainable without serious environmental impact.

Sustainable Use of the Atmosphere

A sustainable society emits to the atmosphere only those substances that will be diluted and consumed in natural bio geochemical cycles without alteration of other chemical constituents, such as ozone. It is well known that the atmosphere of the earth evolved over billions of years from an early oxygen-poor condition to its current oxygen-rich condition. This evolution has been a co-evolution of both the atmosphere and the pant and animal life on earth. The processes that brought about the evolution are still in place, so we can expect that the changes in the composition of the atmosphere that we are causing will be corrected. Unfortunately, the time scale of the evolutionary processes is enormous relative to human life. As a consequence, though righting mechanisms exist, they cannot be expected to respond quickly enough to the insults we are offering to the atmosphere.

The primary changes we are presently causing in the atmosphere are the introduction of trace gases and carbon dioxide--at rates far faster than natural processes can remove them. The trace gases are the chlorine-containing gases (methlychloroform, carbon tetrachloride, chloroflourocarbons, and methane. All these gases trap heat that would otherwise be radiated away from the earth. Thus, all are expected to contribute to the potential for global warming. The CFCs have an additional effect; they deplete ozone from the stratosphere, thereby allowing more ultraviolet (UV) radiation to penetrate to the earth. The UV radiation is implicated in human skin cancers and cataracts.

Carbon dioxide emitted in overwhelming quantities mainly from combustion processes and from forest destruction, is also a heat-trapping gas. Because of its awesome rate of emission, carbon dioxide accounts for over 50% of the potential warming predicted in a number of scientific calculations by the middle of the twenty-first century.

Atmosphere and climate sustainability appears unlikely with the present set of fuels, the fossil fuels, and the present state of use of chlorine-containing gases. Fortunately, the currently used CFCs are being phased out of production by the year 2000 and will be replaced by more ozone-friendly and greenhouse-friendly materials, but our use of fossil fuels only grows with time. Replacing such fuels by renewables and the replacement of use by energy conservation are the approaches needed to achieve atmospheric and climatic stability.

Maintenance of Soil Fertility and Food Supplies

A sustainable society builds rather than depletes its soil base so that adequate food supplies can be ensured. These critical components, food and soil, of a sustainable society are inextricably linked, for failure of the soil due to erosion or contamination or loss of soil nutrients leads to a loss of food-production capacity. At the same time, food supply is tightly linked to climatic stability because a loss of rainfall due to climate change or a shift in temperature regions of the earth may cause areas of the globe once hospitable to certain food crops to become harsh environments for those crops. Hence, the components of a sustainable supply of food, though tied closely to maintenance of soil fertility, have other dimensions as well.

What factors threaten soil? Soils that are forced to growth only a single crop may be robbed of their nutrients by that crop, eventually ailing to support that food plant. That is why farmers are urged to rotate corps and to plant legumes periodically to restore nitrogen to the soil. Water erosion of soils left unprotected by shelter belts or by terracing or y contour plowing can remove massive amounts of top soil. Not only is fertility lost when the organic layer f the soil is washed away, but the fragile mineral soil exposed is subject to further erosion by wind. The wind erosion of the Dust Bowl era is a vivid reminder is how delicate the balance of soil and water is.

Erosion is not the only factor that threatens soil. Irrigation of the soil with salt-laden water can load the soil with damaging minerals. The Fertile Crescent, the region surrounding the Tigris and Euphrates River in Syria and Iraq, was once the breadbasket of the Middle Eastern world (circa 2300 BC). Irrigation with the waters of these rivers left the soil so saline that this portion of the world is now a net importer of grains. The same phenomenon of salt accumulation is at work today in the Ganges basin of the Punjab in India and in the basin of the Indus River in Pakistan. And early evidence suggests the same process may be at work in the heavily irrigated soils of California. Techniques to flood the soil with excess water to dissolve the accumulated salts can prevent the buildup, but irrigators must know how to arrange adequate drainage of this water from the soil.

Soils are also in danger in the regions of the great tropical forests where cutting exposes a nutrient-poor soil that can be used for food crops for a few years or to graze cattle for a few years before the nutrients are used up. Then the soil is left barren, supporting only scrub growth. Recovery of such soil may take centuries. Soils need not support food crops to be valuable. Soils that support trees for timber are also valuable to humankind and to ecosystems as a whole. Mountain range soils, already low in the organic content that resists acidity, are susceptible to mineral leaching by acid rain. Much soils are threatened in eastern North America and in much of Europe by the acid rain that stems from sulfur and nitrogen oxide emissions from fossil fuels combustion. The timber productivity of soils in these regions has already been damaged. The recovery of these soils and their forests, even in the presence of diminished acid rain, is likely to be agonizingly slow.

Sustainable Use of Water

A sustainable society collects and teats its wastewater and treats it drinking water, pricing the water at the cost of obtaining new supplies. It also considers the environmental costs of obtaining new supplies. Water is as important to civilization as blood is to the human body. Without water of adequate quality and quantity, civilization can be brought low. With adequate water, civilizations Four-H. Water makes possible not only adequate food supplies, but it is also a necessity for drinking, washing, and in most places for human waste disposal. Sustainable use of water is linked to climate stability. The global circulation models used to predict the impact of the greenhouse gases on climate generally indicate a warming and drying of the interior land masses of the continents. If the predicted lack of rainfall does not occur, today's' areas of agricultural productivity may be lost; new areas would then be required to sustain an adequate food supply. Again, this change follows from the burning of the finite fossil fuels and the production of carbon dioxide. Thus, sustainable use of water may be thwarted is climate stability is damaged.

A sustainable society might get by with water polluted by human fecal bacteria and protozoans but it would not be a healthy society. It would be racked by cholera, typhoid, and other lesser diarrheal diseases. Drinking water of adequate quality requires not only water treatment processes like sand filtration and chlorination, but relatively clean water to begin with. it is difficult, expensive, and chancy to attempt to "polish" a city's sewage back to drinking water quality. Wastewater (sewage) can be partially cleaned to a condition where it can be used for crop irrigation, golf course and land watering and toilet flushing, but uses beyond these are not recommended.

Drinking water for a city requires a large, relatively unpolluted water source--a river or a lake. Drinking water for rural areas is often drawn from wells, and, in this case, it is essential that ground water remains unpolluted. Water carriage of wastes is a practice that has evolved over the last several centuries. It is not a foolproof method of human waste disposal because receiving bodies of water may become polluted by disease-causing microorganisms, but it is better than human wastes in the street, a condition of nineteenth-century Europe. Water carriage of wastes demands wastewater treatment (swage treatment) at the end of the pipe prior to disposal to the receiving body. If sanitary sewers carry off the wastes from a city and no operating treatment plant is at the end of the pipe, the stage is set for the spread of water-born diseases.

Regions of many nations seem to need more water than is available nearby. Los Angeles imports water from the Colorado and from its distant Northern California rivers. Beijing, China, is considering importation of water from the distant Yellow River. Such needs stem from population and agricultural growth that does not recognize the regional water resource base and hence prices water too cheaply. Importing water from water-rich regions to high water demand regions is a short-term solution unless new water prices reflect the cost of transportation. Additionally, river flow regimes and river ecology are altered when a new river is exploited for a water supply. If water is priced properly, an appropriate conservation occurs and uneconomic uses are diminished.

Sustainable Use of Non fuel Mineral Resources

A sustainable society recycles scarce mineral resources for reuse. The earth's supply of a number of mineral resources appears to be finite. If developing countries were to use minerals such as copper and nickel at the rates currently used by developed countries, serious shortages of these minerals would occur. Although classic economic theory tells us that when resources become scarce, higher prices force a shift to new resources or new technologies, it is not at all certain that the huge future demands projected for many minerals could be satisfied by other resources or by other technologies.

Those minerals whose quantities are not limited at current levels of use are often maldistributed relative to the location of current needs. Furthermore, even where such mineral resources are no maldistributed, the extraction/purification processes are often so energy-intensive or so damaging to the environment as to demand recycle and reuse.

Indeed, a number of mineral production processes are energy-intensive, especially aluminum and steel making. When the energy is drawn from the combustion of fossil fuels resources, which themselves are limited, the atmosphere is affected the emission of nitrogen oxides and sulfur oxides (contributors to acid rain) and carbon dioxide (the prime contributor to greenhouse warming). Nitrogen oxides and sulfur oxides can impact soils. Greenhouse warming implies climate change.

Recycling thus fulfills two goals of sustainable societies: conservation of scarce mineral resources and wise energy use. In addition, of course, recycling reduces the amount of solid or hazardous waste needing disposal.

The problem of stimulating recycling and reuse is an economic one. As an example, so long as the price of producing new aluminum is less than the price of collecting and recycling the metal from its current uses, recycling/reuse will not occur to a significant extent--unless some outside economic stimulus is applied to the system. Unless economic incentives are used to modify the system, vast quantities of energy will continue to be expended on production of materials from primary sources. And associated mining, health, and atmospheric impacts will continue due to the production and combustion of the fossil fuel. At the same time, landfill space will continue to be consumed by the discarded products containing these resources.

The economic incentives that encourage recycling can take many forms, but basically a forced up front injection of money into the system and a return for that money somewhere in the recycle system seems to have the right properties. The upfront deposit on a bottle or can reminds a consumer that there are resource replacement costs, energy costs, and disposal costs associated with the bottle or can. The return of the deposit upon return of the container provides incentives for recycling behaviors. A tax on nonrecycled paper or a tax break on recycled materials serves the same purpose in manufacturing.

It was only in the 1960s that America abandoned deposits on beverage bottles. Now the new England states, Oregon, and other states, to fight litter and reduce solid waste, have legislated deposits on bottles and cans. interestingly, the countries of Western Europe never went to throwaways and never ceased to operate their bottle and can deposit systems.

A similar deposit-return system has been proposed for automobiles, but never implemented. Instead, penalties in the form of fines for the abandonment of junk cars seems to have been utilized to prevent derelict cars from littering streets and fields. you would think that automobiles would be readily recyclable; so much steel should make the auto hulk valuable. Unfortunately, the design of the automobile makes the recycled product less valuable than it could be. So much copper wiring is intertwine into the auto that separation of the copper from the hulk is difficult; the iron product produced from an auto hulk is contaminated with copper and less useful than a cleaner product. Reinforcing bars in concrete construction is one of the limited uses of this contaminated product.

The example makes a point. Design for recyclability is crucial. Modular snap-out copper wiring in a car would improve its value for recycling. Other metal products, such as stoves and refrigerators, could benefit from designs that enhance the value of the product in the recycling process. Stimulating such design to take place is a challenge for sustainable societies.

Recycling of scarce mineral resources is only one facet of another goal for sustainable societies; closed-cycle industrial systems. Such systems would generate little or no waste or, alternatively, generate waste that is usable as raw material in other industrial processes Some pressure for waste reduction and recycling is already present in the form of high costs for scarce metals, end-of-pipe pollution control regulations, and high costs for disposal of wastes in landfills. Nonetheless, government intervention with incentives fore recycling and waste reduction could encourage more recycling and reuse. In addition, ways need to be found to incorporate the environmental costs of raw material into the costs of products.

Maintenance of Biodiversity

A sustainable society maintains the richness and diversity of species in its environment. The number and variety of species in an ecosystem are important components of the environment that supports a sustainable society.

Clearly, certain species are very important to any human society. We depend on particular species for food, for fuel, as sources of medicines or building materials. We depend on certain functioning ecosystems for "ecosystem services"; purification, or regeneration of water, soil, and air, flood control, and moderation of climate. A diversity of species, however, is important for other reasons as well. We value a diverse biota first of all because it represents future options. A variety of species ensures that we will have the materials we will require to meet future needs and to solve future problems. Secondly, we value species richness in and of itself. Bird watchers, visitors to parks, wildlife refuges, and zoos recognize such value instinctively. This is sometimes classed as an aesthetic appreciation of species, but such a designation may not recognize the full value of biological diversity. Humans, having evolved with a rich biota, may actually need this richness in order to function properly and find satisfaction in life.

Finally, we value a diverse biota as something we can pass on to our descendants. This inheritance value stems from the desire of many people to provide for their children at least as much material and spiritual sustenance as they themselves have had.

Maintenance of the resource of biodiversity differs in certain essential ways from the maintenance of nonbiological resources such as minerals. Each species represents a unique whole made up of a specific combination of traits. Loss of all the members of a species--extinction--means the loss of that unique whole. We have no way at present, or in the foreseeable future, to synthesize a species once gone.

On the other hand, members of a species do reproduce. Thus, unlike mineral resources, which have finite limits, species can be cropped, and, under the right circumstances, the resource can renew itself. The first question that sustainable societies must answer is: How much of a given species or ecosystem can be harvested without damaging the ability of the species or ecosystem to renew itself?

Members of a particular species may be intentionally harvested for a variety of reasons--food, fuel, medical, or industrial use--but they are also most incidentally to other human activities. An example is the killing of porpoises in the nets used to catch tuna. Another example is the loss of both animal and plant species when tropical forests are cut down to provide pastures for cattle grazing or land for farming. A second question sustainable societies must answer is: what is the effect of a particular action on plants, animals, and ecosystems?

Unfortunately, we do not have enough information about how species interact within ecosystems to answer these questions with certainty for more than a few species. The information we do have has, by and large, been gained empirically--by seeing what does and does not work. Furthermore, in the process of gaining this information we have already lost or endangered a number of species through over harvesting, through a lack of understanding of the interrelationships among species, and by a failure to take into account the relationship between species richness and the size of a given piece of habitat.

We have endangered many species by not understanding the obligatory interrelationships among species. Fore example, a number of tropical tree species are endangered because their seeds are dispersed by animals or must even pass through the gut of certain birds before they will germinate. As the number of these animals decreases due to hunting and collecting, reproduction of the trees decreases or ends. In a similar way, spotted owls are endangered because they require the ancient trees found in old-growth forest for nesting and they require the species living in the old-growth forest for food. As more and more old-growth forest is logged, the survival of the owl becomes less likely.

As a further example, the Everglades Kite is endangered because it eats only apple snails. These snails are in short supply because their habitat is decreasing as water from sources supplying the Everglades is diverted for the purpose of crop irrigation. Even the apparent inability of certain populations of marine species to regenerate after intensive harvesting may be due to a poorly understood interaction of species. Certain species of whales have not increased in number after hunting of these species was banned. It is speculated that interactions among species have stabilized at new, lower states for these organisms.

The third reason why species are sometimes unexpectedly lost or endangered involves the fragmentation of habitats. Studies on islands have shown that an island twice as big as another does not have twice the number of species. Rather, an island 10 times as large is needed before twice as many species are found. There is evidence that this type of phenomenon also pertains to tropical forests. Thus, loss of 90% of forest habitat may result in a loss of half of the species found in the remaining 10% of the of the forest. In addition, if the patches of forest left are widely separated from each other, recolonization from one patch to another when species are lost becomes impossible.

A major task involved in developing sustainable societies thus involves learning more about both individual species and how species interact in ecosystems, so that wise decisions can be made about the use of biological resources and protection of biological diversity.

Sustainable Use of Biological Resources

A sustainable society protects biological resources of food and materials. In addition to the resource of biodiversity, there are a few natural biological resources that human societies depend upon so heavily they need to be discussed separately. Timber is one such resource; seafood is another. People have long recognized the importance of wild biological resources that are utilized for food and materials. The notion of sustained yield of timber comes out of nineteenth-century forest management in Germany. The ideas of fishery management have likewise been with us for many years. Yet, as knowledgeable as we appear to be in books, we have not yet achieved sustainability in managing our timber supplies or our fisheries.

National forests in the United States are supposed to be harvested on a sustained-yield basis, that is, with a cut no longer than anticipated growth. Yet the cut consistently exceeds new growth. In Canada, cutting of the forests proceeds rapidly. In South America and Southeast Asia the trees of the tropical forests are being lost at alarming rates--felled for timber and burned to clear land for farming or ranching.

In addition to destruction of the resource itself, which is the course not sustainable use, immense quantities of carbon that are tied up in the forests are released as carbon dioxide when the trees are burned, hastening the accumulation of carbon dioxide and increasing the threat of global warming.

Our success in managing ocean fisheries has been similarly dismal. Indiscriminate whaling has already decimated many species of whales. A number of fisheries have failed or appear to be failing due to over harvesting. Examples include the California sardine fishery, the North Sea herring industry, the West Africa / Namibia pilchard fishery, and the Chesapeake oyster industry.

A particular example of unsustainable mining of fishery resources is the use of drift nets by factory ships from Taiwan, Japan, and South Korea. These drift nets, which may extend up to 40 miles in length, literally rake the ocean, capturing and killing all fish indiscriminately. Drift net fishing for salmon in the Pacific has already led to a sharp decline in salmon returning to spawn in West Coast rivers The drift net ships have also been operating in the Atlantic.

A U.N. resolution signed in early 1990 bans drift net fishing on the high seas after June 1992, but without enforcement the "pirate fleet" is likely to stay in business. The protection of the biological resources of timber and of ocean fish is an old concept, but the idea remains empty without the will to enforce appropriate levels of harvesting.

The United Nations Environment Programme, in a report published jointly with two conservation organizations, recommends an international watchdog organization to investigate abuses of the world's environment. If equipped with enforcement powers, such an organization could promote more sustainable uses of the earth's common biological resources.

Limitation of Population Size

A sustainable society aims to limit its population to a size that can be supported indefinitely by its environment. This final component of sustainable societies, the ability to limit their won populations, is probably the most difficult to secure. Population limitation runs directly counter to one of the major biological imperatives--reproduction. For humans, this basic biological imperative to reproduce is overlaid by a thicket of societal expectations, individual goals, and philosophical choices.

Under certain circumstances the net result of all these factors appears to be a stable population size. In the developed countries, personal choices exist about the type of work a person will do or how the income from that work will be spent. Limiting family size is a result of decisions taken by parents to secure economic well-being and personal satisfaction for themselves and for their children. Several countries are currently experiencing zero population growth (Denmark, West Germany), and many others are near that point.

In developing countries and for some people in developed countries, however, these choices may not exist. In such circumstances, children often represent a form of wealth, and the populations of such peoples are consequently growing rapidly. Even in countries where some choice about economic alternatives exists, societal expectations may favor large families or the use of birth control may be frowned upon thus favoring increased population sizes.

As we mentioned in the beginning of this chapter, development has two driving forces. One is the desire to improve living conditions for the size of the population that already exists. The other driving force is to provide water, food sanitation, energy, material wealth for the incremental numbers of people born each ear.

While it is easily understood that no environment could provide for an unlimited number of people indefinitely, humans are still unwilling to grapple with the notion that they live in a finite world, capable of supporting only a specific number of people We appear to be waiting and hoping for technological rescue that will provide us with food, water, energy, and living space until such a time as development reaches all countries and populations naturally stabilize at some sustainable level.

It is not clear, however, that such development can occur at present rates of population growth. It appears less and less likely that technological innovation will sustain us until populations stabilize. Indeed, we may already have surpassed the population size that is sustainable by this earth if all peoples achieve the American standard of living. We don't know if this is the case. We're not talking about it.

Discussions of population limitation inevitably brought up questions on how we could accomplish such limitation. Who will decide who has the ???en and who does not? These are not trivial questions. They have serious implications for freedom of individual choice, racial justice, and economic and social equity for all the nations of the world. But neither are they inherently unanswerable questions. The first step to answering them, however, must be an acceptance that there is a population problem that we should solve before natural processes such as disease, starvation, global warming, or the physical and societal effects of overcrowding solve it for us.

It is likely that there is a size range for the human population that can be sustained indefinitely by the earth's resources and ecosystems. Determining that size range would involve all of the factors we have past discussed; sustainable use of energy, sustainable use of mineral and biological resources, sustainable use of soil, water and air. Because many of these factors involve global resources and effects, no country can make a determination of its sustainable population size without taking into account the populations of other countries. If we would, all of us together, work to determine the appropriate size range for the human population, then we could, and would, begin to solve all of the other issues inherent in limiting human populations. until we make the effort to determine that size range, however, we will find it possible to drift along towards an era of almost certain catastrophes.

Social Characteristics of Sustainable Societies

The preceding discussion has focused mainly on the relationship between human societies and their environment. Truly sustainable societies, of course, also depend upon equitable relationships between people. Racial and economic justice, peace among nations--these are components of sustainable societies. Although these topics are somewhat beyond the scope of this book, neither can they be truly separated from the discussion of environmental issues. Some of our essay writers have touched upon these subjects, notably Richard Moore in his discussion of the unequal burden racial minorities bear and Prime Minister Brundtland in her call for economic justice. Finally, in the next chapter, Paul Raskin urges that the social justice and environmental movements work together for common goals.