ECOSYSTEM MANAGEMENT AND RANGE OF NATURAL VARIABILITY

Definitions of “ecosystem management”:

1. “... it is management that acknowledges the importance of human needs while at the same time confronting the reality that the capacity of our world to meet those needs in perpetuity has limits and depends on the functioning of ecosystems.” — Christensen et al. 1996 (Ecological Society of America).

2. “...a strategy or plan to manage ecosystems for all associated organisms, as opposed to a strategy or plan for managing individual organisms.” --- Forest Ecosystem Management Team 1993. (U.S. Inter-Agency Team).

3. “...a resource management system designed to maintain or enhance ecosystem health and productivity while producing essential commodities and other values to meet human needs and desires within the limits of socially, biologically and economically acceptable risk.”--- American Forest and Paper Association 1993.

4. “...the use of an ecological approach that blends social, physical, economic, and biological needs and values to assure productive, healthy ecosystems.”--- Kaufmann et al. 1994 (Forest Service).

Guiding Principles of Ecosystem Management (Christensen et al. 1996)

1. Intergenerational sustainability

2. Explicit goals

3. Sound ecological models and understanding

4. Ecosystem complexity and connectedness

*5. Recognition of the dynamic character of ecosystems

6. Context and scale

7. Humans as ecosystem components

8. Adaptability and accountability

Some key issues related to the use of the dynamic character of ecosystems as a guiding principle in ecosystem management

1. Equilibrium versus non-equilibrium views of ecosystems

2. Forest health— natural processes versus anthropogenic influences?

3. How do management practices (e.g. logging) mimic natural disturbances (e.g. fire).

4. What is the “Range of Natural Variability” of forest conditions and disturbances?

5. Definition of “reference conditions” at the time of Euro-American settlement.

6. How significant was the impact of Native Americans on forest ecosystems?

__________________________________________________

Approaches and Tools for Defining Range of Natural Variability (from Kaufmann et al. 1994)

1. Historical records

2. Tree rings

3. Palynology and other fossils

4. Preservation of Research Natural Areas

5. Historical photos

6. “Potential” and existing natural vegetation

7. Predictive modeling