The basis of resilience in forest tree species and its use in adaptive forest management in Britain

Forest ecosystems face a range of challenges in the coming decades, of which climate change, pests and diseases are the most serious. These challenges will be overlaid on a background of historically modified and fragmented forests managed in a wide range of ways for different objectives. As northern temperate forests are species-poor in a global context, their resilience to these challenges is fundamentally dependent on the resilience of individual species. However, dealing with each new threat as it arises is unlikely to be cost-effective and probably impractical. A better strategy for establishing long-term resilience would be to harness evolutionary processes, to maximize the capability of individual tree species to respond to new threats by the reorganization of populations via natural selection; in other words, to be resilient. Such processes depend on the internal variability of species, their mechanisms of dispersal and their ability to recruit new genotypes to a population. In this position paper, we review the theoretical concept of resilience, examine how it might be applied to tree populations and assess the state of knowledge of Britain's forests from this perspective.