Ecosystem health demystified: an ecological concept determined by economic means

This paper addresses “ecosystem health”, a concept recently popularised as the way forward in evaluating nature. The concept is often defined in vague expressions and is being seen more as a broad societal aspiration rather than a specific performance measure of ecosystem management. As such, the paper aims to demystify ecosystem health, that is, to demarcate an accurate and feasible characterisation of the concept. To achieve this aim an examination of the various viewpoints of nature is undertaken. Models of ecosystem health, such as the notions of naturalness, genetic fitness, climax, diversity, stability and keystone species are each considered and subsequently deemed inappropriate, especially when viewing ecosystems as “complex self-organising systems”. Complex self-organising systems are non-linear dynamic systems that have multiple steady states and have emergent and chaotic properties. One model that captures this selforganisation process is Holling’s adaptive cycle. However, when investigating this model it was concluded that there is no means to determining which phase within a system state, or state within a system is ecologically “better”. Therefore, ecosystem health cannot be considered in a positive manner established by scientific objectivity. Rather, the concept must be determined in a normative fashion through it is suggested the elicitation of subjective societal values, so to define an optimal management strategy. But, implementing such a strategy is difficult because the changing nature and unpredictability of complex self-organising systems means we cannot focus on “locking-in” ecosystems (or preferences), instead it is argued we must forever adapt to changing ecological conditions