Political ecology — a resilience approach

than design. Similarly, the behavior of biota emerges from the successes of past evolutionary experimentation. This fundamental difference be- tween human and ecological behavior means that understanding the role of people in ecological systems requires not only understanding how peo- ple have acted in the past, but also what they think about the future. Economists generally expect that people’s ‘ra- tional expectations’ will stabilize the behavior of economic systems. The theory of rational expecta- tions proposes that people plan for the future based upon what they think will change in the world and how other people will respond to those changes. If a person’s behavior is based upon his or her expectation of what will happen, and this expectation is based upon a person’s prediction of the behaviors of other people, then when the world is well understood, these expectations will cause individual behaviors to rapidly converge. However, when the world is poorly understood many possible behaviors become equally likely, which makes it difficult to predict people’s behav- iors. Consequently, when the world is unknown and difficult to understand people’s ability to form ‘rational expectations’ will actually destabi- lize system dynamics, making it extremely difficult to predict how a human-ecological system will change in the future Brock and Hommes, 1997. Ecological economics has focussed on integrat- ing ecology and economics. However, the inability of economic theory to predict human behavior in novel, poorly understood situations suggests that it has severe shortcomings in explaining human behavior in many human – ecological interactions. Other social sciences that focus on power, the capacity of an actor to purposefully effect the behavior of another actor, appear to have much to offer the field of ecological economics Gale, 1998.

3. Political ecology — a resilience approach

I define political ecology as combining the con- cerns of ecology and political economy that to- gether represent an ever-changing dynamic tension between ecological and human change, and between diverse groups within society at scales from the local individual to the Earth as a whole. This approach to political ecology derives from my participation in two research collabora- tions: the Resilience Network and the Resilience Alliance http:www.resalliance.org. The Re- silience Network focuses upon the role of diver- sity, conflict, and cross-scale interactions in the structure and dynamics of coupled social-ecologi- cal systems Berkes and Folke, 1998; Gunderson et al., 1995a; Holling and Sanderson, 1996; Gun- derson et al., in preparation1996. These efforts have produced a set of case studies and integrated models of human-nature systems, which include rich empirical descriptions and analyses of re- source management by local people Berkes and Folke, 1998; Colding and Folke, 1997, and the dynamics of regional ecosystems Gunderson et al., 1995a; Pastor et al., 1998. In addition, a number of conceptual models have been used to explore system behavior Ludwig et al., 1997; Peterson et al., 1998. Researchers have used com- plex adaptive systems approaches Hartvigsen et al., 1998; Levin et al., 1998 to develop an inte- grated set of socio-economic ecological models Carpenter et al., 1999a,b; Janssen and Carpenter, 1999. The Resilience Alliance uses the concepts of resilience, the adaptive cycle, scale, and cross- scale dynamics to describe systems dynamics. Be- low, I introduce these concepts and then apply them to analyze the political ecology of salmon in the Columbia River Basin. 3 . 1 . Resilience Ecological resilience is the amount of change or disruption that will cause an ecosystem to switch from being maintained by one set of mutually reinforcing processes and structures to an alterna- tive set of processes and structures Holling, 1973. For example, what fire regime will convert a tropical forest to a grassland? Ecologists also use an alternate definition of resilience Pimm, 1984. Differences between these definitions of resilience are discussed elsewhere Holling, 1996; Peterson et al., 1998. Ecological resilience can be represented using a model of a ball on a surface. The ball represents the state of the system and the surface represents the forces acting to change that state. Pits in this surface represent stable states — states in which the system is organized into a set of mutually reinforcing structures and processes. The slope of the landscape represents the strength of the forces moving the system in a direction. Disturbances, which reorganize a system, move a ball across the landscape’s surface. Ecological resilience of a state corresponds to the width of a stability pit. This width represents the amount of change that a system would have to experience before it moves from one set of mutually reinforcing processes, a pit, to another Fig. 1. Ecological resilience al- lows ecologists and managers to focus upon the likelihood of transitions among different sets of organizing processes and structures, rather than the internal dynamics of specific ecological organizations. Fig. 2. The dynamics of a system as it is dominated by each of the four ecological processes: rapid growth r, conservation K, release V, and reorganization a. The arrows indicate the speed of the cycle. The short, closely spaced arrows indicate a slow and predictable change, while the long arrows indicate rapid and less predictable change. The cycle reflects systemic change in the amount of accumulated capital nutri- ents, resources stored by the dominant structuring process in each phase, and the degree of connectedness within the system. The exit from the cycle at the left of the figure indicates the time at which a systemic reorganization into a less or more productive and organized system is most likely to occur. Adapted from Gunderson et al. 1995b. Fig. 1. The ecological resilience of a system can be illustrated by a ball on a surface. This surface represents the forces acting upon a system in any given state. Pits in this surface represent stable states — states in which the system is organized into a set of mutually reinforcing structures and processes. The slope of the landscape represents the strength of the forces moving the system in a direction. Disturbances reorganize the system moving the ball across the landscape’s surface. Ecological resilience is a measure of the disturbance required to shift a system from being organized around one set of mutually reinforcing structures and processes to another. On a surface, the ecological resilience of a state corresponds to the width of a stability pit. This represents the amount of change that a system would have to experience before the system’s state is moved from one set of mutually reinforcing processes to another. 3 . 2 . Adapti6e cycle Holling 1986 has presented a general model of systemic change that proposes that the internal dynamics of systems cycle through four phases: rapid growth, conservation, collapse, and re-orga- nization. The adaptive cycle is meant to be a tool for thought. It focuses attention upon processes of destruction and reorganization, which are often neglected in favor of growth and conservation. Including these processes provides a more com- plete view of system dynamics that links together system organization, resilience and dynamics. Holling first applied this model to ecological systems, and Gunderson et al. 1995a,b extended it to human-ecological systems, based upon the argument that the continual production of nov- elty by human – nature interactions destabilizes human forward looking behavior. The model pro- poses that as weakly connected processes interact, some processes reinforce one another, rapidly building structure, or organization. This organiza- tion channels and constrains interactions within the system. However, the system becomes depen- dent upon structure and constraint for its persis- tence, leaving it vulnerable to either internal fluctuations or external disruption. Eventually, the system collapses, allowing the remaining dis- organized structures and processes to reorganize Fig. 2. As the organization of a system changes over time its resilience expands and contracts Fig. 3. The exploitation or ‘r’ phase of the adaptive cycle describes a system that is engaged in a process of growth, resource accumulation and storage. The system’s components are weakly con- nected to one another, its internal state is weakly regulated, and the system is resilient. During this period actors can grow rapidly, as they utilize disorganized resources. The actors that thrive are those that develop interrelationships that reduce the impacts of external variation, and reinforce their own expansion. Examples of such processes are the vegetative control of microclimate in ecosystems, and bureaucratic rationalization in human organizations. These processes of organi- zation increase a system’s efficiency at the cost of its flexibility, decreasing its resilience. As a system becomes more organized, the com- petitive advantage shifts from actors that are able to grow rapidly despite environmental variation i.e. r-selected species in ecosystems to those that can effectively manage and benefit from intense competitive and facilitative interactions with other actors i.e. K-selected species. Actors whose per- sistence is not supported by the other actors are displaced from the system, reducing its diversity. Increased system connectivity and efficient re- source leaves few opportunities available for new actors to enter the system. In ecology, an example of such a system is an old-growth forest. A social example is a large corporation, such as Microsoft, that dominates its markets. The future dynamics of a system in this state appear to be gradual, constrained, and predictable, but a system’s in- Fig. 3. As a system progresses through the adaptive cycle its resilience expands and contracts as the system changes and reorganizes. Resilience shrinks as the cycle moves from r to K, where the system becomes more brittle. Until the system flips to a very resilient disturbance state, this state quickly changes the configuration of the system, abolishing constraining forces, leaving the system open to external influence V to a. During this phase the system has little resilience and can be easily reorganized by small inputs. However, as the system reorganizes systematic controls begin to reemerge, producing a resilient set of ecological organizations. creasing dependence upon the persistence of its existing structure leaves it increasingly vulnerable to any process or instability that releases its orga- nized capital. Such a system is increasingly stable, but over a decreasing range of conditions. This reduces the resilience of the system. A disturbance that exceeds a system’s resilience breaks apart the web of mutually reinforcing in- teractions that maintain the system. At this point the system flips abruptly into a transitory distur- bance state that rapidly disperses the system’s accumulated capital and connections until the dis- turbance has altered the system to such an extent that the disturbance exhausts itself. The disorgani- zation and release of accumulated resources is represented by V, or release, phase of the adaptive cycle. This phase is analogous to what Schum- peter 1964 termed creative destruction. Distur- bance processes such as fire, insect outbreaks, floods, ungulate grazing, and disease outbreaks disrupt ecosystems. Social disturbance processes may include financial panics Lewis, 1999, bank- ing crises Chandler, 1977, revolutions Gold- stone, 1991, or pollution events Erikson, 1994. Following a period of destruction, a system’s boundaries and internal connections are tenuous. This state is represented by a, or reorganization, phase in the adaptive cycle. Such a loosely defined system can easily lose or gain resources and ac- tors. During this period a system can easily be reorganized by small inputs. This is the time when exotic species of plants and animals can invade and dominate an ecosystem, or when a group of outsiders can take over an organization. It is the time when chance events can shape the future organization of the system. The new system that emerges from these interactions may replicate a previous system organization or it may be some- thing entirely new. The lack of systemic connec- tion and control makes it difficult to predict what type of organization will form. For example, con- sider the radically different structure of Eastern European countries following the collapse of the Soviet Union, or the succession movements that followed the resignation of Suharto in Indonesia. The adaptive cycle can temporarily break down due to either the loss of ecological capital or the creation of a very robust ecological organization. In the first case, the removal or destruction of ecological resources eliminates the possibility that an ecosystem will reorganize. This could occur when an event, such as an intense forest fire, destroys a site’s soil, removing the ecological sub- strate of the old ecosystem. While life still persists at such a site at the fine scale, local ecological dynamics have been derailed. In the second case, an ecosystem that manages to organize into a very robust ecological organization may be able to survive disturbance, environmental variation, and prevent species turnover. However, such a system is probably only possible in situations where it experiences a limited amount of environmental variation; it is isolated from species or other eco- logical impacts from neighboring ecosystems, and the interactions of its biotic and abiotic processes strongly reinforce each another. Because no ecosystem is completely isolated from other ecosystems, the ecosystems will eventually escape from these traps. Systems stuck in poverty will be enriched by the arrival of organisms or materials from surrounding systems, while stable systems will eventually be disrupted by changes at a larger scale that exceed their capacity to cope. The adaptive cycle shows two very different stages. One, from r to K, is the slow, incremental phase of growth and accumulation. This alterna- tion between accumulating organized resources and experimenting with alternate organizations generates novelty and tests diversity. This alterna- tion may result from a necessary tension between invention, novelty and change and efficiency, con- servation, and stability. It appears that neither of these processes is stable alone. Efficiency under- cuts its own ability to persist by reducing the ability of a system to respond to change, and successful innovations grow while unsuccessful in- novations vanish. 3 . 3 . Scale Ecological organization emerges from the inter- action of structures and processes operating at different scales. I define scale as the resolution and extent of the spatial and temporal frequencies of these structures and processes Peterson et al., 1998. A system exists within an environmental context and is composed of sub-systems. It inter- acts across scales with its environment and sub- systems, all of which can be described by the adaptive cycle. The sensitivity of a system to changes in its sub-systems or its environment depends upon its internal state. Similarly, the degree of impact that the transformation of a system has upon its environment or its sub-sys- tems depends upon the state of those systems. I propose that there are four ways that change propagates through dynamic hierarchies. First, change at a higher level alters a lower level due to the constraints that it places upon it. For exam- ple, offshore fishing for salmon reduces the num- ber of salmon returning to spawn in watersheds along a coast. Second, reorganization at a higher level can trigger reorganization at a lower level. The construction of Grand Coulee dam in the Columbia River illustrates this type of cross-scale change. The dam made it impossible for salmon to travel above or below the dam, extinguishing the migrating salmon populations upstream of the dam. Third, small-scale disturbance can trigger a larger scale collapse if the larger system is in a brittle stage in its adaptive cycle. The introduction of opossum shrimp Mysis relicta into lakes in the Columbia River Basin provides an example of a small event triggering large scale reorganization. The shrimp has caused the reorganization of the lake and surrounding ecosystems, as salmon pop- ulations and the species feeding upon them have declined and been replaced by bottom feeding fish Spencer et al., 1991. Fourth, following the col- lapse of a system, small-scale and surrounding large-scale systems provide the components and constraints out of which a system reorganizes. An example of this type of cross-scale change is pro- vided by the 1934 destruction of Sunbeam dam on the Salmon River. This dam had cut salmon off from their spawning beds, but following its re- moval salmon from neighboring watersheds recol- onized the restored river, establishing new populations Wilkinson, 1992. I have defined a political ecology that focuses upon the dynamic connections between human and natural processes across a range of scales, and I propose that a key aspect of this connection is how the resilience of different systems changes. Below, I illustrate the utility of these concepts by using them to analyze the the poltical ecology of salmon in the Columbia River Basin of western North America.

4. An example: salmon in the Columbia River basin