Restoration of forest resilience: An achievable goal?

Although the concept of resilience is increasingly being incorporated into environmental policy and linked to ecological restoration goals, there is considerable uncertainty regarding how resilience should be defined and measured in practice. Here we briefly review some of the definitions of resilience that have been proposed, including those referred to as ecological and engineering resilience. We also examine evidence for the existence of multiple stable states in forest ecosystems, on which concepts of ecological resilience are based. As evidence for multiple stable states is limited, we suggest that ecological resilience may often have limited value as a goal for forest restoration. We illustrate how engineering resilience can potentially be measured by estimating the rate of forest recovery following disturbance, through analysis of recovery trajectories using meta-analysis and ecological modelling approaches. We also highlight the potential value of resistance as a restoration goal, which can similarly be estimated using such approaches. Based on application of these concepts, we suggest how guidance for restoration practitioners could potentially be developed, to support the practical achievement of both resilience and resistance during forest restoration.