by Brian Walker and David Salt

reviewed by Larry Caswell

There exists an important reality that is often ignored during discussions concerning our human economies. This reality involves the fact that all human economies are directly dependent on and in turn exert an influence upon earth’s living systems. Too often when considering the costs and benefits of enterprises which meet human needs we ignore or downplay the costs to the natural systems which support our economies. Examples around the world of this omission abound in crises of air pollution, water shortages, erosion, desertification, deforestation, extinctions, severe weather events, and changing climate.

Brian Walker and David Salt have written a book which provides a powerful method for analyzing and understanding our economies and earth’s natural systems with which our economies are interconnected. The authors begin with the premise that rather than looking at ecological systems and human systems separately, we must consider these systems together—something they term a “social-ecological system”. These systems are complex and adaptive. They have a certain built in resilience which allows them to respond to a degree of shock or change and continue to meet human needs. It is in fact the resilience of these systems which is the key to their sustainability. I’ll mention two examples of social-ecological systems in Colorado: One would be dry land agriculture in eastern Colorado including the farmers and communities that rely on the short grass prairie ecosystem and the prairie ecosystem itself. Another example could be Rocky Mountain National Park, the surrounding Forest Service lands, and the communities which adjoin the park and depend upon it economically.

Our usual method of organizing these systems has been the idea of optimization. We choose a few goods or services from a complex system and attempt to optimize their output. Examples from the above mentioned systems could include grain or beef output and the generation of tourist and development income respectively. Walker and Salt contend that this approach assumes incremental system growth and change, downplays the complexity of these systems, ignores the possibility of major disturbances, and reduces system resilience to these disturbances, which might eventually lead to permanent changes to the very nature of these systems.

Resilience thinking postulates that social-ecological systems can exist in more than one kind of stable state. Resilience of a system means that it can accept and recover from a shock or disturbance and still remain in its existing stable state. “Stable state” in the sense used here does not mean lack of change within a system, but rather that the system as a whole retains the same general attributes and interrelationships. This system will tend to a general equilibrium. This equilibrium might change over time without the nature of the system changing. The greater the resilience, the greater the shock the system can absorb without rearranging into an entirely different system. All systems have a “threshold” beyond which the system can be pushed into a new stable state with new and differing characteristics and feedbacks. Often the new state is less desirable to our human economies, and it can be very difficult, if not impossible, to return the system to its former state. Consider the “dust bowl” of the early twentieth century and its effect on the entire agricultural economy of the Great Plains. Another example would be the coral reefs of the Caribbean which have been drastically reduced and may never return to their former state.

Walker and Salt contend that we must optimize the resilience of the social-ecological system rather than maximize the output of a particular mix of goods and services. In order to do this we must pay attention to the “slow” variables which are operating within the system. Considering the dry-land farming example we would be concerned with the long term losses in top soil and ground cover. Due to soil erosion coming from farming methods which removed the native protective grasses, the system lost its resilience to respond to a shock: the prolonged drought. History records the change of the entire system into a new state and how this affected the human components of the system.

Another key concept in this book is the idea of “adaptive cycles”. All social-ecological systems change over time, and the system dynamics often follow a predictable pattern. A system goes through four stages: 1. rapid growth, 2. conservation, 3. release, and 4. reorganization. Human policy can intervene to affect these stages, but we must first understand the characteristics of each stage and which stage the system is in at a given point in time. An example of the rapid growth phase for human economies would be businesses taking advantage of new product opportunities. In an ecological community this phase would involve the pioneer plants and successional stages that follow after fires or other disturbances.

The conservation phase could be the climax forest in nature. In an economic system we would see the consolidation of earlier gains in the economy by increasing efficiency, size, and capital accumulation. This phase sees the continuing accumulation of resources in forms that no longer encourage real innovation or major change. Over time the system becomes more efficient in output, resistant to innovations, and less resilient to disturbance.

The release phase can occur in a very short period of time when a disturbance that overcomes the system’s resilience causes the breakdown of interconnections and the system to come apart. The forest experiences a fire or disease outbreak. An industry sees demand for its products evaporate or energy costs escalate. A farm economy experiences an extended drought or loss of product demand. The positive part of this phase is that resources in the form of nutrients in the case of the forest and social and economic capital in the business instancse become available for investment into a reorganized system.

The reorganization phase is chaotic and creative, involving invention, experimentation, and reassortment. This phase can result in a similar cycle to the previous or something entirely novel. A new climax forest may eventually arise, or the system might change to one of grasslands or desert. A corporation might modify or make its product more “green”, or legislation might change the framework of corporations and international trade.

The policy implications for adaptive cycles are that we can influence the length of particular phases, short cut phases, or change the pathways between phases. For example we can allow small patches of a forest to experience fire, and therefore prolong the climax stage of the larger forest while at the same time increasing renewal and biodiversity in scattered patches. A business can invest a significant portion of its resources in new product development or production innovations. An agricultural community might choose to change its farming methods, encourage more biological diversity, and add a recreational component to their operations.

I believe that an enormously important policy implication of the resilience approach is that it can replace deadlocks and confrontation with problem solving efforts by all effected interest groups in resource policy. Once it is recognized that the environment and the economy are part of the same social-ecological system and each depends upon the other to remain in a stable state, then the reason for gridlock evaporates. One of the most interesting aspects of this book is that the authors include five case studies of systems in different parts of the world—their problems with lost resilience and resulting changes to human intervention in these systems arising from cooperation from many stakeholders.

Finally, Resilience Thinking looks to the future and discusses characteristics of the resilient world we must develop. Briefly, some of the prescriptions include the need to encourage diversity in all forms; recognize ecological variability; pay attention to “slow” variables that move us toward thresholds; encourage feedbacks that inform us of the effects of our activities on the systems we depend upon; promote social capital in the form of leadership, trust, and cooperation; encourage innovation and openness to change; diversify the institutions, private and public, available to respond to a changing world; and take into account all ecosystem services (also called natural capital) when making economic decisions. For further information about the resilience concept, beyond reading the book, I direct the reader to the Resilience Alliance website: http://resalliance.org. One great feature of this site is the availability of workbooks for organizations and scientists which can be downloaded for free.