Expired · 6th June 2009
(Part 1) Dr. Buzz Holling, an expert on applied systems analysis, needed a word for the way complex natural systems such as forests adapt to internal and external forces by moving through predictable stages of regeneration, increasing interdependence, growing rigidity and crisis followed by collapse and regeneration again. So he coined the term "panarchy" by combining the ancient Greek name for the god of nature, "Pan", and for leader, "archos".
Holling's insight about such natural cycles came from 50 years of meticulous study. His powerful mathematical models, internationally recognized for their sophistication and accuracy, are now used to describe and predict the course of any natural system as it moves through recurring rhythms of change.
Human civilizations, as Holling learned, also follow the same course as other natural systems, an awareness that has solidified his global reputation as a theorist and helped to coalesce his ideas into an multinational scientific community of thinkers called the Resilience Alliance. This makes panarchy theory particularly relevant and timely because it joins a growing body of thought from climatologists, ecologists, anthropologists, philosophers and others who are examining our modern civilization from the broad perspective of history and are recognizing the same worrisome trends that have occurred in collapsed civilizations of the past. To understand more clearly this basis for worry, we must understand panarchy theory and Holling's insights about the natural cycles of forests.
New forests begin with a growth phase that is characterized by vigorous activity as individual plants and animals jockey for viable positions in this time of incredible opportunity. The number of species "quickly increases as organisms arrive to exploit all available ecological niches" (WorldWatch, Mar./Apr. 09). As the species proliferate and the trees grow larger, biomass accumulates and the "flows of energy, materials and genetic information between the forest's organisms become steadily more numerous and complex" (Ibid.). All this activity, Holling notes, creates "potential" for innovation and invention that may be realized in the forest's biological future.
As the forest ecosystem evolves and matures, its "connectedness" also increases – the degree to which species become more and more linked and interdependent. In this late part of the growth phase, "the mechanisms of self regulation become highly diverse and finely tuned. Species and organisms are progressively more specialized and efficient in using the energy and nutrients available in their niche" (Ibid.). According to panarchy theory, the forest ecosystem begins to rigidify and may even lose diversity as each component becomes locked into its particular role in the functioning forest.
The result is a reduction in the forest's capacity to respond to the impact of a shock. And the forest's high interconnectedness "helps any shock travel faster across the ecosystem" (Ibid.). In Holling's words, as the forest loses its resilience, it becomes "an accident waiting to happen" (Ibid.). Thus a drought, a small change in climate or an unusual insect or pathogen is capable of sending the whole forest ecology into a crisis and collapse before the regeneration phase of the cycle begins again.
This simple and elegant explanation of panarchy theory is complicated by the fact that all natural systems are composed of many adaptive cycles all occurring at the same time – Holling calls them "nested cycles". In a forest, at the smallest and fastest level, microbes in the soil are moving quickly through their own cycles in minutes or hours. At the largest and slowest level, "biogeochemical" changes on the planet are moving imperceptibly through their cycles in centuries or millennia. Meanwhile, specific parts of a forest such as hillsides or valleys or streams may be undergoing their own cycles of adaptive change. The interplay of all these cycles – Holling and his colleagues call this a panarchy – "span a scale in space from soil bacteria to the entire planet and a scale in time from seconds to geologic epochs" (Ibid.).
As Thomas Homer-Dixon explains panarchy theory in his book, The Upside of Down: Catastrophe, Creativity, and the Renewal of Civilization, "The higher and slower-moving cycles provide stability and resources that buffer the forest from shocks and help it recover from collapse.... Meanwhile, the lower and faster-moving cycles are a source of novelty, experimentation and information. Together, the higher and lower cycles help keep the forest's collapse, when it occurs, from being truly catastrophic."
As long as the phases of all these adaptive cycles are occurring at different times, the forest maintains its usual rhythm of cycles. Even when a system collapse does occur, the stabilizing effect of climate will allow regeneration so the forest recovers by beginning its normal cycle again. The "truly catastrophic" occurs when many or all these cycles happen to synchronize at the end of their growth phases. If the build-up of debris in a forest reaches its peak at the same time that a major drought and fire occur, then the heat may be too intense for seeds to survive, the soil burns and the forest may never recover. If an insect infestation occurs – note BC's mountain pine beetle – at the same time as climate warming, then the forest may revert to grassland.
As valuable as panarchy theory is in helping us understand forests, it is much more valuable in helping us identify the worrisome trends occurring in our modern civilization. This, too, is a natural system that has been moving through a growth phase for the last several centuries and may now be approaching crisis.
Next week, more insights about our civilization from panarchy theory.