Cost-effective integrated conservation and restoration priorities by trading off multiple ecosystem services.

Conservation and restoration have long been regarded as two separate management avenues to maintain or enhance ecosystem functioning. Despite the commonalities in goals, restoration is generally considered a lower priority than conservation due to its generally greater cost, uncertainties in multiple trajectories and deals with already degraded habitats. However, when resources and opportunities for meeting conservation needs are limited, restoration could be an imperative avenue to provide additional benefits from conservation. The priority of conservation and restoration should be integrated based on an identical framework cost effectively to obtain the maximum ecological benefits with minimal costs. We propose a methodological framework to integrate conservation and restoration based on theories of Systematic Conservation Planning, which could identify best integrated conservation and restoration pattern in a cost-effective way on the basis of the provisions of multiple ecosystem services (i.e., carbon storage, water yield, soil retention and habitat quality). The trade-offs among four ecosystem services are assessed with an each of 10% increment in the target levels of ecosystem services. We demonstrated our approach at a regional scale, in the Dongting Lake Area, China. Our results showed that conservation is prioritized in a higher proportion of the study area when the targets are low. When the target level became higher, restoration gained more importance with growing area. This highlights that restoration pattern is indispensable when target setting become high and the integrated conservation and restoration planning is more cost efficient than that of conservation alone. Improving the carbon storage and soil retention would also contribute greatly to an increase in other ecosystems, but increasing the water yield and habitat quality would not guarantee an improvement for others. Integrated conservation and restoration planning will facilitate refine target achievement of conservation and restoration recommendations, by the trade-offs between conservation and restoration, and among different ecosystem services, our prioritization framework provides a useful insight in implementing the integrated planning, which can improve the efficiency in increasing ecosystem services compared to use either conservation or restoration ways.