Effectiveness of conservation interventions globally for degraded peatlands in cool-climate regions

Peatlands support unique biodiversity and provide essential ecosystem services, such as regulating climate and providing freshwater and food. However, land-use change, resource extraction and changing climates are threatening peatlands globally. Restoring degraded peatlands requires re-establishing the key features that drive these ecosystems – the hydrological conditions, chemical properties and characteristic biota. Using the best-available evidence to identify management interventions that will effectively abate threats and restore ecological processes can help facilitate successful conservation. ‘Rapid evidence reviews’ have emerged in healthcare as a method of delivering key research findings to policymakers and decision-makers in a timely manner. Here, we used a rapid review approach to identify, appraise and synthesise scientific evidence on the effectiveness of conservation interventions intended to restore the hydrological conditions, chemical properties and/or characteristic biota of degraded boreal, montane, alpine and temperate peatlands globally. We found that there is consistent evidence that rewetting, shading or mulching, reprofiling, mowing, controlling grazers and active revegetation can improve the condition of degraded peatlands. Taking a whole-system approach was reported as essential to successful conservation because the hydrological conditions, chemical properties and biota are intrinsically linked. There is consistent evidence that restoring peatlands can enhance the ecosystem service of carbon storage. We demonstrate that applying the rapid review approach to a conservation problem: 1) proved efficient for synthesising evidence from 453 individual studies collected through 23 reviews, and 2) yielded a valuable synthesis of the common interventions to support effective, evidence-based conservation and recovery of peatlands globally. This can enable policymakers and practitioners to apply the best-available research knowledge when addressing this important challenge.