Resilience is the capacity of a social-ecological system to absorb or withstand perturbations and other stressors such that the system remains within the same regime, essentially maintaining its structure and functions. It describes the degree to which the system is capable of self-organization, learning and adaptation (Holling 1973, Gunderson & Holling 2002, Walker et al. 2004).
People are part of the natural world. We depend on ecosystems for our survival and we continuously impact the ecosystems in which we live from the local to global scale. Resilience is a property of these linked social-ecological systems (SES). When resilience is enhanced, a system is more likely to tolerate disturbance events without collapsing into a qualitatively different state that is controlled by a different set of processes. Furthermore, resilience in social-ecological systems has the added capacity of humans to anticipate change and influence future pathways.
Reduced resilience increases the vulnerability of a system to smaller disturbances that it could previously cope with. Even in the absence of disturbance, gradually changing conditions, e.g., nutrient loading, climate, habitat fragmentation, etc., can surpass threshold levels, triggering an abrupt system response. The new state of the system may be less desirable if ecosystem services that benefit humans are diminished, as in the case of productive freshwater lakes that become eutrophic and depleted of their biodiversity. Restoring a system to it's previous state can be complex, expensive, and sometimes impossible. Research suggests that to restore some systems to their previous state requires a return to conditions that existed well before the point of collapse (Scheffer et al. 2001).
Theoretical advances in recent years include a set of seven principles that have been identified for building resilience and sustaining ecosystem services in social-ecological systems. The principles include: maintaining diversity and redundancy, managing connectivity, managing slow variables and feedbacks, fostering complex adaptive systems thinking, encouraging learning, broadening participation, and promoting polycentric governance systems (Biggs et al. 2012).
Gunderson, L. H. and C. S. Holling, eds. 2002. Panarchy: Understanding Transformations in Systems of Humans and Nature. Island Press, Washington DC.
Holling, C. S. 1973. Resilience and stability of ecological systems. Annu Rev Ecol Syst 4:1-23.
Scheffer, M., S. Carpenter, J. A. Foley, C. Folke, and B. Walker. 2001. Catastrophic shifts in ecosystems. Nature 413:591-596.
Walker, B., C. S. Holling, S. R. Carpenter, and A. Kinzig. 2004. Adaptability and Transformability in Social-Ecological Systems. Ecology and Society 9:5.
Keywords: resilience, theory, principles, diversity, slow variables, feedbacks, complex systems, systems thinking