The uncomfortable bottom line of sustainability is the insight that the biosphere is limited. In its crude form, the idea of ‘limits to growth’ dominated 1970s environmentalism. Evidence of resource substitution (fibre optics for copper cables, light plastics for steel) and improved resource use technologies (e.g. improved technologies for the discovery and exploitation of oil reserves) have allowed this view to be pilloried as unrealistic ‘flat-earthism’. On the other hand, the spread of persistent organic pollutants, the ozone hole and the growing certainly of anthropogenic climate change caused by CO2 and other greenhouse gases demonstrate that the fundamental point is perfectly valid. The earth’s capacity to yield products for human consumption, to absorb or sequestrate human wastes (especially novel compounds), and to yield ecosystem services are all of them limited. The idea that that there is always somewhere to absorb externalities is flawed, and it is a myth of progress that living systems will always recover from human demands.
Moreover, as environmental capacity is reached, institutions for sharing the earth are placed under intolerable strain.
The science of resilience is central to an understanding of the planetary future, and the metaphor of resilience (and its limits) is valuable for its contribution to more general debate. For decades, message taken from the
science of ecology by society more generally was that ecosystems were homeostatic – that once a stress was removed, they would bounce back to their former state. This comforting metaphor implied that there was no reason to fear that human misuse of the global environment would lead to irretrievable breakdown. The bleak message of the Gaia hypothesis, that the biosphere could be understood as a self-regulating system, was reinterpreted with shocking anthropocentric complacency to imply that it would therefore always support human life. The earth may function to maintain life, but not necessarily life in the stunning biodiversity we know today, and certainly not human life.
Ecology has moved on. Non-linear dynamics are accepted as an inherent element in ecosystem function. Polluted lakes do not necessarily return to their former state when pollution stops; climate can not be expected to vary around some mean approximating to the conditions of the last 30 years; it is highly likely that extinction of certain species will change the amplitude and frequency of ecosystem change in ways that constrain human opportunities; novel compounds and broad-taxon genetic manipulation may well generate shifts in ecosystem form and function.
The biosphere is not infinite. As Edward Wilson observes, ‘the biosphere, all organisms combined, makes up only one part in ten billion of the earth's mass. It is sparsely distributed through a kilometre-thick layer of soil, water and air stretched over a half billion square kilometres of the surface'.
The capacity of nature to meet human needs depends on both its internal dynamics and its dynamic responses to human stresses. The resilience of the biosphere is critical to the sustainability of human enterprise on earth.
Moreover, as environmental capacity is reached, institutions for sharing the earth are placed under intolerable strain.
The science of resilience is central to an understanding of the planetary future, and the metaphor of resilience (and its limits) is valuable for its contribution to more general debate. For decades, message taken from the
science of ecology by society more generally was that ecosystems were homeostatic – that once a stress was removed, they would bounce back to their former state. This comforting metaphor implied that there was no reason to fear that human misuse of the global environment would lead to irretrievable breakdown. The bleak message of the Gaia hypothesis, that the biosphere could be understood as a self-regulating system, was reinterpreted with shocking anthropocentric complacency to imply that it would therefore always support human life. The earth may function to maintain life, but not necessarily life in the stunning biodiversity we know today, and certainly not human life.
Ecology has moved on. Non-linear dynamics are accepted as an inherent element in ecosystem function. Polluted lakes do not necessarily return to their former state when pollution stops; climate can not be expected to vary around some mean approximating to the conditions of the last 30 years; it is highly likely that extinction of certain species will change the amplitude and frequency of ecosystem change in ways that constrain human opportunities; novel compounds and broad-taxon genetic manipulation may well generate shifts in ecosystem form and function.
The biosphere is not infinite. As Edward Wilson observes, ‘the biosphere, all organisms combined, makes up only one part in ten billion of the earth's mass. It is sparsely distributed through a kilometre-thick layer of soil, water and air stretched over a half billion square kilometres of the surface'.
The capacity of nature to meet human needs depends on both its internal dynamics and its dynamic responses to human stresses. The resilience of the biosphere is critical to the sustainability of human enterprise on earth.
Source:
The Future of Sustainability Re-thinking Environment and Development in the Twenty-first Century
Report of the IUCN Renowned Thinkers Meeting, 29-31 January 2006
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