Managing Uncertainty Important In Ecological Balance

It depends on whom you ask, says Ann Kinzig, an Arizona State University associate professor in the School of Life Sciences specializing in biology and society. According to her research, ideas about nature's balance diverge across lines of culture, livelihood and political ideology.

"Some view nature as fragile, easily upset by human activity and in need of protection," Kinzig says. "Others view nature as extremely robust and nearly endless in its capacity to continue to supply needed resources in the face of heavy human exploitation. Still others have more nuanced viewpoints or inconsistent perceptions."

The condition of the natural world is not an either-or proposition -- the biosphere is never perfectly balanced or wholly poised on the brink of a precipitous crash, Kinzig says. It can be at once robust and fragile, stable and unstable. Moreover, instability in one part of the ecological system may be required to maintain stability in another, as when variations in the populations of individual plant species act to stabilize the overall biomass of an ecosystem. One's interpretation is greatly dependent upon which features are examined and at what scale.

Similarly, humans can have a beneficial or a detrimental effect on resilience, or both. According to Kinzig, there is no theoretical reason to conclude that ecological systems would grow more resilient in absence of human influences.

"Human interaction could, in theory, serve to either increase or decrease resilience," she says. "In practice, it does both, though the examples of human interaction degrading resilience are more numerous."

If uncertainty can never fully be eliminated from our understanding of nature, then scientists, decision makers and the public must consider it in their deliberations -- and ask what risks they are willing to take in managing the world's ecological systems.

"Uncertainty can and should influence management decisions," Kinzig says. "Our perceptions about the robustness or vulnerability of nature may be wrong. If we have as our model that nature is fragile, and it isn't, what opportunities do we miss? If we perceive it to be robust, and it isn't, what consequences do we suffer?"

Kinzig will present her observations on Feb. 17 at the American Association for the Advancement of Science annual meeting.