The role of species composition in the emergence of alternate vegetation states in a temperate rainforest system

Fletcher, Michael-Shawn; Cadd, Haidee R; Mariani, Michela; Hall, Tegan L; Wood, Samuel W

Abstract

Context: Forest systems are dynamic and can alternate between alternative stable states in response to climate, disturbance and internal abiotic and biotic conditions. Switching between states depends on the crossing of critical thresholds and the establishment of feedbacks that drive (and maintain) changes in ecosystem functioning. The nature of these thresholds and the workings of these feedbacks have been well-researched, however, the factors that instigate movement toward and across a threshold remain poorly understood.
Objectives: In this paper, we explore the role of species composition in initiating ecosystem state change in a temperate landscape mosaic of fire-prone and fire-sensitive vegetation systems.
Methods: We construct two 12-kyr palaeocecological records from two proximal (230 m apart) sites in Tasmania, Australia, and apply the Alternative Stable States model as a framework to investigate ecosystem feedbacks and resilience threshold dynamics.
Results: Our results indicate that, in this system, invasion by pyrogenic Eucalyptus species is a key factor in breaking down negative (stabilising) feedbacks that maintain pyrophobic sub-alpine rainforest.
Conclusions: We conclude that the emergence of an alternative stable pyrogenic state in these relic rainforest systems depends on the extent of pyrophytic species within the system. These findings are critical for understanding resilience in forest ecosystems under future climate and land management changes and are relevant to fire-adapted cool-temperate ecosystems globally.

Citation

Fletcher, M., Cadd, H. R., Mariani, M., Hall, T. L., & Wood, S. W. (2020). The role of species composition in the emergence of alternate vegetation states in a temperate rainforest system. Landscape Ecology, 35(10), 2275–2285. https://doi.org/10.1007/s10980-020-01110-9

• Journal Article Type: Article
• Acceptance Date: Sep 3, 2020
• Online Publication Date: Sep 16, 2020
• Publication Date: 2020-10
• Deposit Date: Sep 16, 2020
• Publicly Available Date: Sep 17, 2021
• Journal: Landscape Ecology
• Print ISSN: 0921-2973
• Electronic ISSN: 1572-9761
• Peer Reviewed: Peer Reviewed
• Volume: 35
• Issue: 10
• Pages: 2275–2285
• DOI: https://doi.org/10.1007/s10980-020-01110-9
• Keywords: Alternative stable states; Critical transitions, Eucalyptus; Rainforest; Resilience; Tasmania
• Public URL: https://nottingham-repository.worktribe.com/output/4906208
• Publisher URL: https://link.springer.com/article/10.1007/s10980-020-01110-9
• Additional Information: Received: 19 March 2020; Accepted: 7 September 2020; First Online: 16 September 2020