Historically, the conceptual framework used to study ecosystems relies on how ecosystem dynamics are unidirectionally affected by human activities on one side, and biogeophysical drivers on the other. This allegedly outdated approach ignores more complex interplays and feedbacks, and has been gradually replaced by a more inclusive framework that explicitly includes human decisions, cultural institutions, and economic systems (social drivers) (McGinnis and Ostrom, 2014).
The extended framework (integrated ecology) reflects the resilient and sustained regular interactions between social and biophysical factors, within several spatial, temporal and organisational scales (possibly hierarchically linked). System functioning depends on critical natural, socioeconomic, and cultural resources, that flow, are shared, recycled, and consumed, under the influences of the social and biogeophysical drivers and systems. According to Redman et al. (2004) this perpetually dynamic, complex system with continuous adaptation, is a Social-Ecological System (SES)
SESs are a major focus of contemporary approaches to environmental management (Lade et al., 2013) and paradigm shifts have become commonplace (Gonzalez et al., 2008). An emerging property of SESs is their stability, whose dynamics depend on three complementary attributes: i) resilience, ii) adaptability, and iii) transformability (Walker et al., 2004).
Conceptual representation of the three attributes affecting the stability dynamics of a social-ecological system (SES). SES is represented by a two-faced Janus marble, in reference to the role of its social- and biogeophysical- drivers. SES stability depends on the complementary states of resilience, adaptability, and transformability.
Resilience (this document’s focus) lacks an official/universally accepted definition, as multiple changes/adaptations have been proposed (Gunderson et al., 2002, Walker et al., 2006, Walker et al., 2004) since Holling’s 1973 paper (Holling, 1973). Importantly, however, all these definitions revolve around a perturbation event, and the system ability to absorb and recover from this disturbance. Reynolds (2006) summarises this elasticity as the situation where environmental forcing causes a deviation in structure, but the systems reverts to its original condition, and points out how resilience leads to constancy over a long time (rev. in (Reynolds, 2006)).
Conceptual representation of lake stability and turbidity as a function of nutrients (Scheffer et al., 1993).
Many ecosystems are highly dynamic, and spatial and temporal changes are the norm. This dynamicity is often due to large-scale disturbance factors (Elmqvist et al., 2004) and the system intrinsic resilience. As external disturbance is often unavoidable resilience has become the focus of much attention, as a driver of change that has obvious important effects on monitoring- and recovery- strategies (Folke, 2006). The idea of a stable and resilient SES, easily recoverable by environmental managers and eternally able to revert to a pre-disturbance state, upon removal of anthropogenic stressors is outdated. Under a newer and allegedly more promising resilience-perspective, policies are shifted towards managing the capacity of SESs to deal with unavoidable and unpredictable changes (Folke, 2006). Resilience quantification is challenging and an active research area (Quinlan et al., 2016), but its relationship with SES stability has critical implications for contemporary environmental management approaches.