How Strong Sustainability Became Safety.

The core commitment of strong sustainability, SS, is that nature really is different: there are strict limits to the substitutability of natural and other kinds of capital. Initially, the threat to sustainability was perceived as human greed and impatience, and the goal of SS to address resource scarcity was to sustain resource stocks, the flow of environmental services, and/or the harvest for human benefit. For landscapes and ecosystems, the SS goal was preservation, often in a gestalt framing: preserved or not. Two developments beginning around the mid-20th century—increasing awareness of the variability of natural systems, and the revolutionary changes in thinking motivated by the study of complex dynamic systems, CDS—re-oriented SS toward Safety, i.e., minimizing exposure to risk defined as threat of harm. Around 2010, the sustainability agenda for CDS shifted from identifying early warning indicators enabling timely interventions to forestall adverse regime change to promoting resilience by expanding scale and encouraging patchwork patterns of systems in various stages of their adaptive cycles. Nevertheless, the need for natural resources to substitute for depleted exhaustibles suggests a continuing role for commercial agriculture, plantation forestry, and managed fisheries. I conclude with a paradox still to be resolved: the need for continued and increased production from renewable resources to replace depleted exhaustibles suggests SS-motivated management practices that seem obsolete from a CDS perspective. [ABSTRACT FROM AUTHOR]