Applying the concept of niche breadth to understand urban tree mortality in the UK

Kim, Eun Hye; Hitchmough, James D.; Cameron, Ross W.; Schrodt, Franziska; Martin, Kevin W.E.; Cubey, Rob

Abstract

Accelerated climate change has raised concerns about heightened vulnerability of urban trees, spurring the need to reevaluate their suitability. The urgency has also driven the widespread application of climatic niche-based models. In particular, the concept of niche breadth (NB), the range of environmental conditions that species can tolerate, is commonly estimated based on species occurrence data over the selected geographic range to predict species response to changing conditions. However, in urban environments where many species are cultivated out of the NB of their natural distributions, additional empirical evidence beyond presence and absence is needed not only to test the true tolerance limits but also to evaluate species' adaptive capacity to future climate. In this research, mortality trends of Acer and Quercus species spanning a 21-year period (2000-2021) from tree inventories of three major UK botanic gardens - Royal Botanic Gardens, Kew (KEW), Westonbirt, the National Arboretum (WESB), and Royal Botanic Garden Edinburgh (RBGE) - were analyzed in relation to their NB under long-term drought stress. As a result, Acer species were more responsive to drought and heat stress. For Acer, positioning below the lower limits of the precipitation of warmest quarter led to an increase in the probability of annual mortality by 1.2 and 1.3 % at KEW and RBGE respectively. In addition, the mean cumulative mortality rate increased corresponding to an increase in the number of bioclimatic niche variables positioned below the lower limits. On the other hand, Quercus species in general exhibited comparable resilience regardless of their niche positions. Moreover, Mediterranean oaks were most tolerant, with cumulative mortality rates that were lower than those of native oaks in the UK. These findings further highlight the importance of incorporating ecological performance and recognizing species-specific adaptive strategies in climatic niche modeling.

Citation

Kim, E. H., Hitchmough, J. D., Cameron, R. W., Schrodt, F., Martin, K. W., & Cubey, R. (2023). Applying the concept of niche breadth to understand urban tree mortality in the UK. Science of the Total Environment, 902, Article 166304. https://doi.org/10.1016/j.scitotenv.2023.166304

• Journal Article Type: Article
• Acceptance Date: Aug 12, 2023
• Online Publication Date: Aug 22, 2023
• Publication Date: Dec 1, 2023
• Deposit Date: Oct 17, 2023
• Publicly Available Date: Oct 17, 2023
• Journal: Science of the Total Environment
• Print ISSN: 0048-9697
• Electronic ISSN: 1879-1026
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 902
• Article Number: 166304
• DOI: https://doi.org/10.1016/j.scitotenv.2023.166304
• Keywords: Niche position, Urban botanic gardens, Drought stress, Urban tree assessment, Heatwaves, Tree inventory data
• Public URL: https://nottingham-repository.worktribe.com/output/25344588
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S004896972304929X?via%3Dihub