Learning to adapt to an uncertain future: linking genes, trees, people and processes for more resilient treescapes (newLEAF)

Treescapes - our woodlands, our forests, our urban trees - are critical to our environment, our health and well-being and our ability to transition to a zero carbon economy via plans to substantially increase tree numbers in the landscape. However, climate change and increasing risks from pests and disease threaten the UK treescape like never before. This future is uncertain but we do know that our treescapes must change to survive and thrive. Although we may see treescapes as permanent or fixed, in truth they have an amazing capacity to be dynamic and shift on timescales that are relevant to human lifespans. Indeed, it is often only human interventions that have prevented populations from changing and adapting. For example, where uncontrolled grazing is allowed, little or no regeneration occurs and there is no opportunity for new genetic diversity to enter the population and for the population to adapt. For treescapes to be resilient, change is essential, but this can take many forms - from low intervention, allowing regeneration but taking little other action, to highly managed situations like production forestry, where deliberate choices can be taken to deploy particular genotypes to track environmental shifts. To understand, live with and shape change within treescapes, we must first learn from how treescapes have changed in the past, then quantify how much potential they have to change in the future, and finally develop ways of building change into our treescapes and the ways we interact with them.
This proposal outlines newLEAF, a project to evaluate options for using the extensive natural genetic variation within tree species to keep pace with expected changes in climate and the biotic (pest & disease) environment. Firstly, we will learn from the past 100 years of treescape management in the UK, bringing together historical information on policy and practice with data on changing tree populations on the ground to understand the link between choices made at a policy level and the outcomes for treescape resilience. Then we will quantify the rate of adaptation that can be achieved by both natural and human selection in key tree species for the UK, focusing on traits linked to fitness in forecasted environments and susceptibility to pests and pathogens. We will compare the impacts that natural regeneration versus planting has on the development of biotic communities associated with trees, particularly fungi and insect vectors with the potential to mediate risk.
Drawing directly from the experimental work, we will design models incorporating data on trait variability and will evaluate how internal adaptability within tree species can be used, in varying compositions, configurations and under different management regimes, to generate diverse and dynamic treescapes with an in-built capability to track environmental changes, even when that change is uncertain. We will test tools and strategies to minimise risk from pests and pathogens, especially those associated with planned increases in tree numbers in the landscape, learning from the interactions between our set of focal species and their associated communities. Working with stakeholders, we will explore the social and economic drivers that can be deployed to effect change in the landscape, learning from historical environmental policies and their outcomes in the UK and from key case studies in similar systems across Europe. A particular focus will be on people engaging with the concepts of uncertainty, dynamism and change, studying new ways to integrate science and the arts and creating new works framed around these ideas. Bringing together this diverse and multidisciplinary team, we will produce new research, guidance, policy recommendations, art and science-based tools that will advance the cause of resilience in the UK's future treescape.