Sunday, May 8, 2011

The Paradox of Wilderness Intervention

Let's face it, wilderness managers are damned if they do, damned if they don't. When it comes to designated wilderness areas like state parks, active intervention (fire suppression, invasive species control, etc.) means injecting artificiality into systems where artificiality is anathema. On the flip side, however, lack of intervention means important values like native biodiversity, ecosystem function, and ecosystem services, could be lost forever. In Beyond Naturalness: Rethinking Park Wilderness Stewardship in an Era of Rapid Change, editors David Cole and Laurie Yung look at this problem through the lens of several competing wilderness management approaches.

Historically, early approaches to management focused around the notion of "naturalness," but this concept proved to be too vague. Early laws enshrined the language of "naturalness" and caused havoc: its many definitions meant implementation was often arbitrary and ill-coordinated. Additionally, new anthropological research into the impact of early human cultures demolished the idea of a historic "primitive state." Modern ecology, with the adoption of dynamic equilibrium models, destroyed the notion that nature exists in a "natural" equilibrium or climax state. Add to this the global reach of human impact and it's very unclear what our specific management goals are regarding wilderness areas.

Four "post-naturalness" approaches attempt to categorize the different facets of "naturalness":

1. Hands-Off Approach: This is just what it sounds like: not taking any conscious action that manipulates, controls, or hinders the conditions (e.g. habitat), components (e.g. species), or processes (e.g. fire) of an ecological system. Let nature roll the dice. This approach is an alternative to being locked into managing a rapidly-changing system not fully understood. It encourages scientific humility, eliminates the risk of unintended adverse consequences (of intervention), and provides unmanipulated control data. However, this approach may increase the risk to specific elements of biodiversity, and result in the loss of cultural resources (archeological sites, etc.) and property.

2. Ecological Integrity Approach: In this approach, managed intervention is justified in order to maintain ecosystem health, biodiversity, sustainability, etc. Managers must set up specific goals such as: retaining a large population of native species, selecting and monitoring viable indicator species, mixing disturbance regimes (fire, herbivory) over time and area, and ensuring productivity and decomposition operate within limits for system persistence (not too much entropy, example: clear-cutting, bark beetles). This approach is very dependent on the effective operationalization of goals (measuring the right things).

3. Historical Fidelity Approach: Maintain a connection to the past; pass legacy of natural and cultural heritage. Restore past conditions wherever possible. In this approach, species that were historically the most abundant, iconic, or charismatic are the species most critical to ecosystem function (as opposed to keystone species or species that are least redundant). In addition to cultural and philosophical justifications, animals have evolved to fit niches and thus their survival potential is reduced if future environmental conditions deviate too much from the past. A challenge to this approach concerns the inherent dynamism of ecosystems.

4. Resilience Approach: This approach targets an ecosystem's ability to adapt to change, specifically "the capacity of a system to tolerate disturbance without collapsing into a qualitatively different state that is controlled by a different set of processes." Instead of pursuing specific landscape or ecological objectives, managers should focus on the core goal of sustaining functional, adaptable systems. Ecosystem qualities that typically enhance resilience are diversity and modularity (ecosystem sub-systems are coherent and loosely-connected so that if one fails, others can persist and rebuild).

Each approach has a certain naivete, yet also an understandable appeal. By being so narrow in scope, the trade-offs between approaches are revealed, making comparisons much easier. Clearly some mixture of all four approaches is currently being implemented, by design or by default, which is warranted. However I do believe the resilience framework shows the most promise considering the level of global ecological decline.

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