The increasing frequency, intensity, and uncertainty of high-impact disturbance events due to global change are negatively impacting our ability to predict and manage forest growth and dynamics, therefore challenging the capacity to maintain ecological resilience and ecosystem services from forests worldwide. While forest ecosystems are complex adaptive systems, a multi-scale perspective and regional landscape management planning can improve our ability to manage forests under increasing socio-ecological changes and uncertainties. Although several methodological challenges persist, indices of functional diversity and indicators derived with the network theory calculated at both stand and landscape levels have been increasingly proposed as proxy for quantifying forest resilience under relatively unknown future conditions. In this study we aimed at coupling spatially explicit tree-community and landscape models with functional diversity theory using network theory and to determine optimal forest management strategies to maximize ecological resilience to global change factors. We developed a new meta-model coupling stand and landscape scale forest dynamics with functional diversity theory. In addition to evaluate landscape-scale indicators such as connectivity, redundancy, centrality and modularity between forest patches, this tool allows the simulation of different levels of management intensities and the impact of natural disturbance events. We used the Centre-du-Quebec landscape as case study area to simulate and assess several plausible levels of management intensity under various single and combined known press and known and unknown pulse disturbances of various intensities over a 100 years period.
Results/Conclusions
Our simulations done at both the stand and landscape scales show that managing forested landscapes using network theory can allow managers to develop efficient forest management practices to maximize the overall landscape resilience to broad-scale disturbances. We also show that increasing both forest structural and compositional diversity affects positively many resilience indicators at the landscape-level. To increase forest resilience, we recommend a mixture of even and uneven-aged silvicultural interventions that maximizes forest patches’ functional diversity and redundancy executed within and across patches. We also show that the planting of native and non-native tree species that increase both functional diversity and redundancy of key traits of dominant species are necessary to maintain the overall forest resilience under the most extreme combinations of disturbance events (e.g., extreme drought events, pest and pathogens outbreaks, windthrow). Overall, our study demonstrates the usefulness of a novel and innovative way to evaluate and increase resilience-based forest management for large fragmented forest landscapes.