Tipping points in systematic conservation planning: conservation of ecosystem services may be accompanied by a collapse in regional capacity for biodiversity conservation
The Australian Museum, Australia
The Strategic Plan of the Convention on Biological Diversity (CBD) encourages economic valuation of ecosystem services. Such economic values for intact lands often may exceed the economic benefits of conversion to non-conservation uses, thus overcoming the opportunity costs of conservation. Many see this as an attractive pathway for biodiversity conservation. The few studies integrating ecosystem services into systematic conservation planning (SCP) suggest that conservation of ecosystem services localities promotes regional biodiversity outcomes.
Here, I calculated SCP efficiency-frontier curves and regional biodiversity conservation outcomes, for varying magnitude of ecosystem services values, in the South Coast Region of New South Wales, Australia. The region has information on regional biodiversity, opportunity costs (forestry production values) and recognized ecosystem services including water, recreation, and wilderness values. I examined scenarios in which ecosystem services values exceeded low forestry production values for some localities. Such localities then provided conservation of both services and local biodiversity. Increasing the magnitude of estimated ecosystem services values shifted the efficiency-frontier curve for regional biodiversity conservation versus forestry production away from high net benefits. Initially, as the magnitude of estimated ecosystem services values increased, the new SCP solutions (for a given cost) nevertheless showed only small reduction in biodiversity conservation level. But then a continued increase in magnitude of ecosystem services values moved the SCP solutions towards a tipping point in which the regional biodiversity conservation achievement level fell precipitously.
SCP also can help avoid such tipping points: a small adjustment in total area conserved, or in ecosystem services valuation, may enable much better biodiversity outcomes. Countries have the flexibility to modify the new CBD goals, providing an opportunity to focus less on individual goals, and more on trade-offs among them, using SCP. Without such efforts, emerging ecosystem services valuations could be accompanied by unnecessarily steep reductions in regional biodiversity conservation.