ABSTRACT
In the past, economic growth has been achieved at the expense of natural resource depletion, without stocks being allowed to regenerate. Ecosystems have been widely degraded and biodiversity has been lost at an unprecedented pace (Millennium Ecosystem Assessment, 2005). If current resource-intensity continues, environmental tipping points may create ecosystem disequilibria that will threaten human livelihoods.1 While climate change is the most pressing challenge, many other environmental imbalances are expected to become unsustainable in the near future. A group of Resilience Alliance researchers has identified nine ‘planetary boundaries’ that must not be crossed if major risks to humanity are to be avoided. They include limits to freshwater use, ocean acidification, loss of biodiversity and chemical pollution (Rockstro¨m et al., 2009).
