ganic farming will become not only the healthiest but also the cheapest means of producing food.
Eco-taxes are now under serious discussion in several European countries and are likely to be introduced in all countries sooner or later. To remain competitive under such a new system, managers and entrepreneurs will need to become ecologically literate. In particular, detailed knowledge of the flow of energy and matter through a company will be essential, and this is why the newly developed practice of eco-auditing” will be of paramount importance . 6 An eco-audit is concerned with the environmental consequences of the flows of material, energy, and people through a company and therefore with the true costs of production.
Partnership is an essential characteristic of sustainable communities. The cyclical exchanges of energy and resources in an ecosystem are sustained by pervasive cooperation. Indeed, we have seen that since the creation of the first nucleated cells over two billion years ago, life on Earth has proceeded through ever more intricate arrangements of cooperation and coevolution. Partnership—the tendency to associate, establish links, live inside one another, and cooperate—is one of the hallmarks of life.
In human communities partnership means democracy and personal empowerment, because each member of the community plays an important role. Combining the principle of partnership with the dynamic of change and development, we may also use the term coevolution” metaphorically in human communities. As a partnership proceeds, each partner better understands the needs of the other. In a true, committed partnership both partners learn and change—they coevolve. Here again we notice the basic tension between the challenge of ecological sustainability and the way in which our present societies are structured, between economics and ecology. Economics emphasizes competition, expansion, and domination; ecology emphasizes cooperation, conservation, and partnership.
The principles of ecology mentioned so far—interdependence, the cyclical flow of resources, cooperation, and partnership—are all different aspects of the same pattern of organization. This is how ecosystems organize themselves to maximize sustainability.
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Once we have understood this pattern, we can ask more detailed questions. For example, what is the resilience of these ecological communities? How do they react to outside disturbances? These questions lead us to two further principles of ecology—flexibility and diversity—that enable ecosystems to survive disturbances and adapt to changing conditions.
The flexibility of an ecosystem is a consequence of its multiple feedback loops, which tend to bring the system back into balance whenever there is a deviation from the norm, due to changing environmental conditions. For example, if an unusually warm summer results in increased growth of algae in a lake, some species of fish feeding on these algae may flourish and breed more, so that their numbers increase and they begin to deplete the algae. Once their major source of food is reduced, the fish will begin to die out. As the fish population drops, the algae will recover and expand again. In this way the original disturbance generates a fluctuation around a feedback loop, which eventually brings the fish/algae system back into balance.
Disturbances of that kind happen all the time, because things in the environment change all the time, and thus the net effect is continual fluctuation. All the variables we can observe in an ecosystem—population densities, availability of nutrients, weather patterns, and so forth—always fluctuate. This is how ecosystems maintain themselves in a flexible state, ready to adapt to changing conditions. The web of life is a flexible, ever-fluctuating network. The more variables are kept fluctuating, the more dynamic is the system; the greater is its flexibility; and the greater is its ability to adapt to changing conditions.
All ecological fluctuations take place between tolerance limits. There is always the danger that the whole system will collapse when a fluctuation goes beyond those limits and the system can no longer compensate for it. The same is true of human communities. Lack of flexibility manifests itself as stress. In particular, stress will occur when one or more variables of the system are pushed to their extreme values, which induces increased rigidity throughout the system. Temporary stress is an essential aspect of life, but prolonged stress is harmful and destructive to the system. These
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considerations lead to the important realization that managing a social system—a company, a city, or an economy—means finding the optimal values for the system’s variables. If one tries to maximize any single variable instead of optimizing it, this will invariably lead to the destruction of the system as a whole.
The principle of flexibility also suggests a corresponding strat- egy of conflict resolution. In every community there will invariably be contradictions and conflicts, which cannot be resolved in favor of one or the other side. For example, the community will need stability and change, order and freedom, tradition and innovation. Rather than by rigid decisions, these unavoidable conflicts are much better resolved by establishing a dynamic balance. Ecological literacy includes the knowledge that both sides of a conflict can be important, depending on the context, and that the contradictions within a community are signs of its diversity and vitality and thus contribute to the system’s viability.
In ecosystems the role of diversity is closely connected with the system’s network structure. A diverse ecosystem will also be resilient, because it contains many species with overlapping ecological functions that can partially replace one another. When a particular species is destroyed by a severe disturbance so that a link in the network is broken, a diverse community will be able to survive and reorganize itself, because other links in the network can at least partially fulfill the function of the destroyed species. In other words, the more complex the network is, the more complex its pattern of interconnections, the more resilient it will be.
In ecosystems the complexity of the network is a consequence of its biodiversity, and thus a diverse ecological community is a resilient community. In human communities ethnic and cultural diversity may play the same role. Diversity means many different relationships, many different approaches to the same problem. A diverse community is a resilient community, capable of adapting to changing situations.
However, diversity is a strategic advantage only if there is a truly vibrant community, sustained by a web of relationships. If the community is fragmented into isolated groups and individuals, diversity can easily become a source of prejudice and friction. But
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if the community is aware of the interdependence of all its members, diversity will enrich all the relationships and thus enrich the community as a whole, as well as each individual member. In such a community information and ideas flow freely through the entire network, and the diversity of interpretations and learning styles— even the diversity of mistakes—will enrich the entire community.
These, then, are some of the basic principles of ecology—interdependence, recycling, partnership, flexibility, diversity, and, as a consequence of all those, sustainability. As our century comes to a close and we go toward the beginning of a new millennium, the survival of humanity will depend on our ecological literacy, on our ability to understand these principles of ecology and live accord- ingly.