摘要

Sustainability of ecosystem services to humanity will depend on knowledge of how ecosystems work in their natural states, which can then be carried over to managed states. The objective of this paper is to describe four properties of ecosystems taken as natural conditions to be maintained under exploitation. Three of these are design properties: near-steady-state or extremal dynamics, dominance of indirect effects, and positive utility in network organization. One is a regulatory property: distributed multivariable control. The methodology of the paper is mathematical modeling. The design properties are drawn from the inherent formalism in models. The control property is demonstrated by manipulating model parameters to achieve a management goal. The results show that: (1) natural ecosystems operate near, but not at, steady states or extrema, and ecosystems exploited for human purposes should be similarly maintained (near-steady-state imperative); (2) indirect effects are dominant in natural ecosystem networks, and should be taken into account in managing ecosystems for human benefits (nonlocal imperative); (3) natural ecosystems enhance positive relationships among their constituents, and ecosystems maintained for human services should be managed to maximize their expression of mutualistic and synergistic network properties (nonzero imperative); and (4) natural ecosystems are regulated by checks and balances distributed across many control variables in interactive networks, so that obtaining human services from ecosystems should similarly be through coordinated use of many, not few, control variables (multifactorial control imperative). The conclusion from these results is that ecosystems under natural conditions evidence organizational properties evolved over evolutionary time, and management for sustainable extraction of ecosystem services should seek to preserve and emulate these properties in the new exploited states.

  • 出版日期2010-9