Identifying management options for modified vegetation: application of the novel ecosystems framework to a case study in the Galapagos Islands.

摘要

In highly modified, or 'novel', ecosystems it is often difficult to decide where limited conservation funds should be spent to reach management goals. We tested a recently-developed decision framework for novel ecosystems to help identify management options for modified native vegetation in the humid highlands of the Galapagos Islands. First, we conducted a data-based ecosystem assessment that compared contemporary vegetation to historical vegetation. This assessment characterised the biotic novelty of contemporary vegetation and resulted in a map of novelty over the landscape. Second, we considered processes affecting ecosystem change and barriers preventing the return to historical vegetation using state-and-transition models that incorporated the spatial extent of the contemporary vegetation states. Finally, we discussed options informed by our results that would address the management goals for our case study. Some of these options involve trade-offs between the goals of conserving biodiversity and maintaining ecosystem services, while other options address both goals in a win-win scenario. The novel ecosystems decision framework was a useful tool for identifying management options because it framed results that enabled a quantitative comparison of the degree of novelty of ecosystems across the landscape and also defined barriers to restoration. Tools that accounted for the spatial extent of the novel ecosystems complemented the framework, particularly for application at a landscape scale. Our approach could be broadly applied to the assessment and management of modified ecosystems, especially where historical data are available to calculate measures of biotic novelty.