Managing for the unexpected: Building resilient forest landscapes to cope with global change

• Published in: Global change biology 2022-07, Vol.28 (14), p.4323-4341
• Main Authors: Mina, Marco, Messier, Christian, Duveneck, Matthew J., Fortin, Marie‐Josée, Aquilué, Núria
• Format: Article
• Language: English
• Subjects: Animals; Carbon; Carbon capture and storage; Carbon sequestration; carbon stock; Climate Change; Disturbances; Drought; Ecological adaptation; Ecological effects; ecological resilience; Ecosystem; Ecosystem disturbance; Ecosystem services; Ecosystems; Environmental impact; forest ecosystem management; Forest ecosystems; forest landscape modeling; Forest management; Forest productivity; Forests; functional diversity; Global warming; Hardwoods; Herbivores; insect outbreaks; Insecta; Insects; LANDIS‐II; Landscape; Natural disturbance; Network analysis; Outbreaks; Pest outbreaks; Pests; Resilience; Structure-function relationships; Terrestrial ecosystems; Trees
• ISSN: 1354-1013; 1365-2486; 1365-2486
• DOI: 10.1111/gcb.16197

Natural disturbances exacerbated by novel climate regimes are increasing worldwide, threatening the ability of forest ecosystems to mitigate global warming through carbon sequestration and to provide other key ecosystem services. One way to cope with unknown disturbance events is to promote the ecological resilience of the forest by increasing both functional trait and structural diversity and by fostering functional connectivity of the landscape to ensure a rapid and efficient self‐reorganization of the system. We investigated how expected and unexpected variations in climate and biotic disturbances affect ecological resilience and carbon storage in a forested region in southeastern Canada. Using a process‐based forest landscape model (LANDIS‐II), we simulated ecosystem responses to climate change and insect outbreaks under different forest policy scenarios—including a novel approach based on functional diversification and network analysis—and tested how the potentially most damaging insect pests interact with changes in forest composition and structure due to changing climate and management. We found that climate warming, lengthening the vegetation season, will increase forest productivity and carbon storage, but unexpected impacts of drought and insect outbreaks will drastically reduce such variables. Generalist, non‐native insects feeding on hardwood are the most damaging biotic agents for our region, and their monitoring and early detection should be a priority for forest authorities. Higher forest diversity driven by climate‐smart management and fostered by climate change that promotes warm‐adapted species, might increase disturbance severity. However, alternative forest policy scenarios led to a higher functional and structural diversity as well as functional connectivity—and thus to higher ecological resilience—than conventional management. Our results demonstrate that adopting a landscape‐scale perspective by planning interventions strategically in space and adopting a functional trait approach to diversify forests is promising for enhancing ecological resilience under unexpected global change stressors. How expected and unexpected changes in climate and biotic disturbances affect ecological forest resilience? Forest landscape simulations in Southern Canada show that climate change will increase forest productivity and carbon stocks, but unexpected impacts of drought and insect outbreaks will drastically affect the forest. Alternative forest manag