ABSTRACT
The need for a measurable and clear definition of ecosystem level properties has become a central issue in evaluating healthy ecosystems (Costanza 1992; Mageau et al. 1995), to provide insights into system dynamics at multiple scales (Zaccarelli, Petrosillo, and Zurlini 2008), and to possibly foresee systems’ responses to future shocks or changes in disturbance regimes. 126 Ecosystem health is defined as the condition of normality in the linked processes and functions that constitute ecosystems (Rapport 1995), and is defined in terms of vigor, resilience, and organization (Mageau et al. 1995). Ecosystem integrity refers to “the unimpaired condition in which ecosystems show little or no impact from human actions” (Angermeier and Karr 1994). The notions of ecosystem health and integrity represent different but related intellectual constructs (Karr and Chu 1999), so that an intact ecosystem is also healthy, but a healthy ecosystem may not necessarily be characterized by integrity. Such concepts are considered both a matter of social values and requirements for persistence or resilience of ecosystems to supply man with valuable services (Rapport 1995). However, they are mainly focused on the ecological state of ecosystems, which includes humans only in terms of the possible impacts they may have, and do not consider human perception or human role in supporting such properties.
